| 1 | /* Target-struct-independent code to start (run) and stop an inferior |
| 2 | process. |
| 3 | |
| 4 | Copyright (C) 1986-2021 Free Software Foundation, Inc. |
| 5 | |
| 6 | This file is part of GDB. |
| 7 | |
| 8 | This program is free software; you can redistribute it and/or modify |
| 9 | it under the terms of the GNU General Public License as published by |
| 10 | the Free Software Foundation; either version 3 of the License, or |
| 11 | (at your option) any later version. |
| 12 | |
| 13 | This program is distributed in the hope that it will be useful, |
| 14 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | GNU General Public License for more details. |
| 17 | |
| 18 | You should have received a copy of the GNU General Public License |
| 19 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 20 | |
| 21 | #include "defs.h" |
| 22 | #include "displaced-stepping.h" |
| 23 | #include "infrun.h" |
| 24 | #include <ctype.h> |
| 25 | #include "symtab.h" |
| 26 | #include "frame.h" |
| 27 | #include "inferior.h" |
| 28 | #include "breakpoint.h" |
| 29 | #include "gdbcore.h" |
| 30 | #include "gdbcmd.h" |
| 31 | #include "target.h" |
| 32 | #include "target-connection.h" |
| 33 | #include "gdbthread.h" |
| 34 | #include "annotate.h" |
| 35 | #include "symfile.h" |
| 36 | #include "top.h" |
| 37 | #include "inf-loop.h" |
| 38 | #include "regcache.h" |
| 39 | #include "value.h" |
| 40 | #include "observable.h" |
| 41 | #include "language.h" |
| 42 | #include "solib.h" |
| 43 | #include "main.h" |
| 44 | #include "block.h" |
| 45 | #include "mi/mi-common.h" |
| 46 | #include "event-top.h" |
| 47 | #include "record.h" |
| 48 | #include "record-full.h" |
| 49 | #include "inline-frame.h" |
| 50 | #include "jit.h" |
| 51 | #include "tracepoint.h" |
| 52 | #include "skip.h" |
| 53 | #include "probe.h" |
| 54 | #include "objfiles.h" |
| 55 | #include "completer.h" |
| 56 | #include "target-descriptions.h" |
| 57 | #include "target-dcache.h" |
| 58 | #include "terminal.h" |
| 59 | #include "solist.h" |
| 60 | #include "gdbsupport/event-loop.h" |
| 61 | #include "thread-fsm.h" |
| 62 | #include "gdbsupport/enum-flags.h" |
| 63 | #include "progspace-and-thread.h" |
| 64 | #include "gdbsupport/gdb_optional.h" |
| 65 | #include "arch-utils.h" |
| 66 | #include "gdbsupport/scope-exit.h" |
| 67 | #include "gdbsupport/forward-scope-exit.h" |
| 68 | #include "gdbsupport/gdb_select.h" |
| 69 | #include <unordered_map> |
| 70 | #include "async-event.h" |
| 71 | #include "gdbsupport/selftest.h" |
| 72 | #include "scoped-mock-context.h" |
| 73 | #include "test-target.h" |
| 74 | #include "gdbsupport/common-debug.h" |
| 75 | |
| 76 | /* Prototypes for local functions */ |
| 77 | |
| 78 | static void sig_print_info (enum gdb_signal); |
| 79 | |
| 80 | static void sig_print_header (void); |
| 81 | |
| 82 | static void follow_inferior_reset_breakpoints (void); |
| 83 | |
| 84 | static bool currently_stepping (struct thread_info *tp); |
| 85 | |
| 86 | static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info *); |
| 87 | |
| 88 | static void insert_step_resume_breakpoint_at_caller (struct frame_info *); |
| 89 | |
| 90 | static void insert_longjmp_resume_breakpoint (struct gdbarch *, CORE_ADDR); |
| 91 | |
| 92 | static bool maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc); |
| 93 | |
| 94 | static void resume (gdb_signal sig); |
| 95 | |
| 96 | static void wait_for_inferior (inferior *inf); |
| 97 | |
| 98 | /* Asynchronous signal handler registered as event loop source for |
| 99 | when we have pending events ready to be passed to the core. */ |
| 100 | static struct async_event_handler *infrun_async_inferior_event_token; |
| 101 | |
| 102 | /* Stores whether infrun_async was previously enabled or disabled. |
| 103 | Starts off as -1, indicating "never enabled/disabled". */ |
| 104 | static int infrun_is_async = -1; |
| 105 | |
| 106 | /* See infrun.h. */ |
| 107 | |
| 108 | void |
| 109 | infrun_async (int enable) |
| 110 | { |
| 111 | if (infrun_is_async != enable) |
| 112 | { |
| 113 | infrun_is_async = enable; |
| 114 | |
| 115 | infrun_debug_printf ("enable=%d", enable); |
| 116 | |
| 117 | if (enable) |
| 118 | mark_async_event_handler (infrun_async_inferior_event_token); |
| 119 | else |
| 120 | clear_async_event_handler (infrun_async_inferior_event_token); |
| 121 | } |
| 122 | } |
| 123 | |
| 124 | /* See infrun.h. */ |
| 125 | |
| 126 | void |
| 127 | mark_infrun_async_event_handler (void) |
| 128 | { |
| 129 | mark_async_event_handler (infrun_async_inferior_event_token); |
| 130 | } |
| 131 | |
| 132 | /* When set, stop the 'step' command if we enter a function which has |
| 133 | no line number information. The normal behavior is that we step |
| 134 | over such function. */ |
| 135 | bool step_stop_if_no_debug = false; |
| 136 | static void |
| 137 | show_step_stop_if_no_debug (struct ui_file *file, int from_tty, |
| 138 | struct cmd_list_element *c, const char *value) |
| 139 | { |
| 140 | fprintf_filtered (file, _("Mode of the step operation is %s.\n"), value); |
| 141 | } |
| 142 | |
| 143 | /* proceed and normal_stop use this to notify the user when the |
| 144 | inferior stopped in a different thread than it had been running |
| 145 | in. */ |
| 146 | |
| 147 | static ptid_t previous_inferior_ptid; |
| 148 | |
| 149 | /* If set (default for legacy reasons), when following a fork, GDB |
| 150 | will detach from one of the fork branches, child or parent. |
| 151 | Exactly which branch is detached depends on 'set follow-fork-mode' |
| 152 | setting. */ |
| 153 | |
| 154 | static bool detach_fork = true; |
| 155 | |
| 156 | bool debug_infrun = false; |
| 157 | static void |
| 158 | show_debug_infrun (struct ui_file *file, int from_tty, |
| 159 | struct cmd_list_element *c, const char *value) |
| 160 | { |
| 161 | fprintf_filtered (file, _("Inferior debugging is %s.\n"), value); |
| 162 | } |
| 163 | |
| 164 | /* Support for disabling address space randomization. */ |
| 165 | |
| 166 | bool disable_randomization = true; |
| 167 | |
| 168 | static void |
| 169 | show_disable_randomization (struct ui_file *file, int from_tty, |
| 170 | struct cmd_list_element *c, const char *value) |
| 171 | { |
| 172 | if (target_supports_disable_randomization ()) |
| 173 | fprintf_filtered (file, |
| 174 | _("Disabling randomization of debuggee's " |
| 175 | "virtual address space is %s.\n"), |
| 176 | value); |
| 177 | else |
| 178 | fputs_filtered (_("Disabling randomization of debuggee's " |
| 179 | "virtual address space is unsupported on\n" |
| 180 | "this platform.\n"), file); |
| 181 | } |
| 182 | |
| 183 | static void |
| 184 | set_disable_randomization (const char *args, int from_tty, |
| 185 | struct cmd_list_element *c) |
| 186 | { |
| 187 | if (!target_supports_disable_randomization ()) |
| 188 | error (_("Disabling randomization of debuggee's " |
| 189 | "virtual address space is unsupported on\n" |
| 190 | "this platform.")); |
| 191 | } |
| 192 | |
| 193 | /* User interface for non-stop mode. */ |
| 194 | |
| 195 | bool non_stop = false; |
| 196 | static bool non_stop_1 = false; |
| 197 | |
| 198 | static void |
| 199 | set_non_stop (const char *args, int from_tty, |
| 200 | struct cmd_list_element *c) |
| 201 | { |
| 202 | if (target_has_execution ()) |
| 203 | { |
| 204 | non_stop_1 = non_stop; |
| 205 | error (_("Cannot change this setting while the inferior is running.")); |
| 206 | } |
| 207 | |
| 208 | non_stop = non_stop_1; |
| 209 | } |
| 210 | |
| 211 | static void |
| 212 | show_non_stop (struct ui_file *file, int from_tty, |
| 213 | struct cmd_list_element *c, const char *value) |
| 214 | { |
| 215 | fprintf_filtered (file, |
| 216 | _("Controlling the inferior in non-stop mode is %s.\n"), |
| 217 | value); |
| 218 | } |
| 219 | |
| 220 | /* "Observer mode" is somewhat like a more extreme version of |
| 221 | non-stop, in which all GDB operations that might affect the |
| 222 | target's execution have been disabled. */ |
| 223 | |
| 224 | static bool observer_mode = false; |
| 225 | static bool observer_mode_1 = false; |
| 226 | |
| 227 | static void |
| 228 | set_observer_mode (const char *args, int from_tty, |
| 229 | struct cmd_list_element *c) |
| 230 | { |
| 231 | if (target_has_execution ()) |
| 232 | { |
| 233 | observer_mode_1 = observer_mode; |
| 234 | error (_("Cannot change this setting while the inferior is running.")); |
| 235 | } |
| 236 | |
| 237 | observer_mode = observer_mode_1; |
| 238 | |
| 239 | may_write_registers = !observer_mode; |
| 240 | may_write_memory = !observer_mode; |
| 241 | may_insert_breakpoints = !observer_mode; |
| 242 | may_insert_tracepoints = !observer_mode; |
| 243 | /* We can insert fast tracepoints in or out of observer mode, |
| 244 | but enable them if we're going into this mode. */ |
| 245 | if (observer_mode) |
| 246 | may_insert_fast_tracepoints = true; |
| 247 | may_stop = !observer_mode; |
| 248 | update_target_permissions (); |
| 249 | |
| 250 | /* Going *into* observer mode we must force non-stop, then |
| 251 | going out we leave it that way. */ |
| 252 | if (observer_mode) |
| 253 | { |
| 254 | pagination_enabled = 0; |
| 255 | non_stop = non_stop_1 = true; |
| 256 | } |
| 257 | |
| 258 | if (from_tty) |
| 259 | printf_filtered (_("Observer mode is now %s.\n"), |
| 260 | (observer_mode ? "on" : "off")); |
| 261 | } |
| 262 | |
| 263 | static void |
| 264 | show_observer_mode (struct ui_file *file, int from_tty, |
| 265 | struct cmd_list_element *c, const char *value) |
| 266 | { |
| 267 | fprintf_filtered (file, _("Observer mode is %s.\n"), value); |
| 268 | } |
| 269 | |
| 270 | /* This updates the value of observer mode based on changes in |
| 271 | permissions. Note that we are deliberately ignoring the values of |
| 272 | may-write-registers and may-write-memory, since the user may have |
| 273 | reason to enable these during a session, for instance to turn on a |
| 274 | debugging-related global. */ |
| 275 | |
| 276 | void |
| 277 | update_observer_mode (void) |
| 278 | { |
| 279 | bool newval = (!may_insert_breakpoints |
| 280 | && !may_insert_tracepoints |
| 281 | && may_insert_fast_tracepoints |
| 282 | && !may_stop |
| 283 | && non_stop); |
| 284 | |
| 285 | /* Let the user know if things change. */ |
| 286 | if (newval != observer_mode) |
| 287 | printf_filtered (_("Observer mode is now %s.\n"), |
| 288 | (newval ? "on" : "off")); |
| 289 | |
| 290 | observer_mode = observer_mode_1 = newval; |
| 291 | } |
| 292 | |
| 293 | /* Tables of how to react to signals; the user sets them. */ |
| 294 | |
| 295 | static unsigned char signal_stop[GDB_SIGNAL_LAST]; |
| 296 | static unsigned char signal_print[GDB_SIGNAL_LAST]; |
| 297 | static unsigned char signal_program[GDB_SIGNAL_LAST]; |
| 298 | |
| 299 | /* Table of signals that are registered with "catch signal". A |
| 300 | non-zero entry indicates that the signal is caught by some "catch |
| 301 | signal" command. */ |
| 302 | static unsigned char signal_catch[GDB_SIGNAL_LAST]; |
| 303 | |
| 304 | /* Table of signals that the target may silently handle. |
| 305 | This is automatically determined from the flags above, |
| 306 | and simply cached here. */ |
| 307 | static unsigned char signal_pass[GDB_SIGNAL_LAST]; |
| 308 | |
| 309 | #define SET_SIGS(nsigs,sigs,flags) \ |
| 310 | do { \ |
| 311 | int signum = (nsigs); \ |
| 312 | while (signum-- > 0) \ |
| 313 | if ((sigs)[signum]) \ |
| 314 | (flags)[signum] = 1; \ |
| 315 | } while (0) |
| 316 | |
| 317 | #define UNSET_SIGS(nsigs,sigs,flags) \ |
| 318 | do { \ |
| 319 | int signum = (nsigs); \ |
| 320 | while (signum-- > 0) \ |
| 321 | if ((sigs)[signum]) \ |
| 322 | (flags)[signum] = 0; \ |
| 323 | } while (0) |
| 324 | |
| 325 | /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of |
| 326 | this function is to avoid exporting `signal_program'. */ |
| 327 | |
| 328 | void |
| 329 | update_signals_program_target (void) |
| 330 | { |
| 331 | target_program_signals (signal_program); |
| 332 | } |
| 333 | |
| 334 | /* Value to pass to target_resume() to cause all threads to resume. */ |
| 335 | |
| 336 | #define RESUME_ALL minus_one_ptid |
| 337 | |
| 338 | /* Command list pointer for the "stop" placeholder. */ |
| 339 | |
| 340 | static struct cmd_list_element *stop_command; |
| 341 | |
| 342 | /* Nonzero if we want to give control to the user when we're notified |
| 343 | of shared library events by the dynamic linker. */ |
| 344 | int stop_on_solib_events; |
| 345 | |
| 346 | /* Enable or disable optional shared library event breakpoints |
| 347 | as appropriate when the above flag is changed. */ |
| 348 | |
| 349 | static void |
| 350 | set_stop_on_solib_events (const char *args, |
| 351 | int from_tty, struct cmd_list_element *c) |
| 352 | { |
| 353 | update_solib_breakpoints (); |
| 354 | } |
| 355 | |
| 356 | static void |
| 357 | show_stop_on_solib_events (struct ui_file *file, int from_tty, |
| 358 | struct cmd_list_element *c, const char *value) |
| 359 | { |
| 360 | fprintf_filtered (file, _("Stopping for shared library events is %s.\n"), |
| 361 | value); |
| 362 | } |
| 363 | |
| 364 | /* True after stop if current stack frame should be printed. */ |
| 365 | |
| 366 | static bool stop_print_frame; |
| 367 | |
| 368 | /* This is a cached copy of the target/ptid/waitstatus of the last |
| 369 | event returned by target_wait()/deprecated_target_wait_hook(). |
| 370 | This information is returned by get_last_target_status(). */ |
| 371 | static process_stratum_target *target_last_proc_target; |
| 372 | static ptid_t target_last_wait_ptid; |
| 373 | static struct target_waitstatus target_last_waitstatus; |
| 374 | |
| 375 | void init_thread_stepping_state (struct thread_info *tss); |
| 376 | |
| 377 | static const char follow_fork_mode_child[] = "child"; |
| 378 | static const char follow_fork_mode_parent[] = "parent"; |
| 379 | |
| 380 | static const char *const follow_fork_mode_kind_names[] = { |
| 381 | follow_fork_mode_child, |
| 382 | follow_fork_mode_parent, |
| 383 | NULL |
| 384 | }; |
| 385 | |
| 386 | static const char *follow_fork_mode_string = follow_fork_mode_parent; |
| 387 | static void |
| 388 | show_follow_fork_mode_string (struct ui_file *file, int from_tty, |
| 389 | struct cmd_list_element *c, const char *value) |
| 390 | { |
| 391 | fprintf_filtered (file, |
| 392 | _("Debugger response to a program " |
| 393 | "call of fork or vfork is \"%s\".\n"), |
| 394 | value); |
| 395 | } |
| 396 | \f |
| 397 | |
| 398 | /* Handle changes to the inferior list based on the type of fork, |
| 399 | which process is being followed, and whether the other process |
| 400 | should be detached. On entry inferior_ptid must be the ptid of |
| 401 | the fork parent. At return inferior_ptid is the ptid of the |
| 402 | followed inferior. */ |
| 403 | |
| 404 | static bool |
| 405 | follow_fork_inferior (bool follow_child, bool detach_fork) |
| 406 | { |
| 407 | int has_vforked; |
| 408 | ptid_t parent_ptid, child_ptid; |
| 409 | |
| 410 | has_vforked = (inferior_thread ()->pending_follow.kind |
| 411 | == TARGET_WAITKIND_VFORKED); |
| 412 | parent_ptid = inferior_ptid; |
| 413 | child_ptid = inferior_thread ()->pending_follow.value.related_pid; |
| 414 | |
| 415 | if (has_vforked |
| 416 | && !non_stop /* Non-stop always resumes both branches. */ |
| 417 | && current_ui->prompt_state == PROMPT_BLOCKED |
| 418 | && !(follow_child || detach_fork || sched_multi)) |
| 419 | { |
| 420 | /* The parent stays blocked inside the vfork syscall until the |
| 421 | child execs or exits. If we don't let the child run, then |
| 422 | the parent stays blocked. If we're telling the parent to run |
| 423 | in the foreground, the user will not be able to ctrl-c to get |
| 424 | back the terminal, effectively hanging the debug session. */ |
| 425 | fprintf_filtered (gdb_stderr, _("\ |
| 426 | Can not resume the parent process over vfork in the foreground while\n\ |
| 427 | holding the child stopped. Try \"set detach-on-fork\" or \ |
| 428 | \"set schedule-multiple\".\n")); |
| 429 | return true; |
| 430 | } |
| 431 | |
| 432 | if (!follow_child) |
| 433 | { |
| 434 | /* Detach new forked process? */ |
| 435 | if (detach_fork) |
| 436 | { |
| 437 | /* Before detaching from the child, remove all breakpoints |
| 438 | from it. If we forked, then this has already been taken |
| 439 | care of by infrun.c. If we vforked however, any |
| 440 | breakpoint inserted in the parent is visible in the |
| 441 | child, even those added while stopped in a vfork |
| 442 | catchpoint. This will remove the breakpoints from the |
| 443 | parent also, but they'll be reinserted below. */ |
| 444 | if (has_vforked) |
| 445 | { |
| 446 | /* Keep breakpoints list in sync. */ |
| 447 | remove_breakpoints_inf (current_inferior ()); |
| 448 | } |
| 449 | |
| 450 | if (print_inferior_events) |
| 451 | { |
| 452 | /* Ensure that we have a process ptid. */ |
| 453 | ptid_t process_ptid = ptid_t (child_ptid.pid ()); |
| 454 | |
| 455 | target_terminal::ours_for_output (); |
| 456 | fprintf_filtered (gdb_stdlog, |
| 457 | _("[Detaching after %s from child %s]\n"), |
| 458 | has_vforked ? "vfork" : "fork", |
| 459 | target_pid_to_str (process_ptid).c_str ()); |
| 460 | } |
| 461 | } |
| 462 | else |
| 463 | { |
| 464 | struct inferior *parent_inf, *child_inf; |
| 465 | |
| 466 | /* Add process to GDB's tables. */ |
| 467 | child_inf = add_inferior (child_ptid.pid ()); |
| 468 | |
| 469 | parent_inf = current_inferior (); |
| 470 | child_inf->attach_flag = parent_inf->attach_flag; |
| 471 | copy_terminal_info (child_inf, parent_inf); |
| 472 | child_inf->gdbarch = parent_inf->gdbarch; |
| 473 | copy_inferior_target_desc_info (child_inf, parent_inf); |
| 474 | |
| 475 | scoped_restore_current_pspace_and_thread restore_pspace_thread; |
| 476 | |
| 477 | set_current_inferior (child_inf); |
| 478 | switch_to_no_thread (); |
| 479 | child_inf->symfile_flags = SYMFILE_NO_READ; |
| 480 | child_inf->push_target (parent_inf->process_target ()); |
| 481 | thread_info *child_thr |
| 482 | = add_thread_silent (child_inf->process_target (), child_ptid); |
| 483 | |
| 484 | /* If this is a vfork child, then the address-space is |
| 485 | shared with the parent. */ |
| 486 | if (has_vforked) |
| 487 | { |
| 488 | child_inf->pspace = parent_inf->pspace; |
| 489 | child_inf->aspace = parent_inf->aspace; |
| 490 | |
| 491 | exec_on_vfork (); |
| 492 | |
| 493 | /* The parent will be frozen until the child is done |
| 494 | with the shared region. Keep track of the |
| 495 | parent. */ |
| 496 | child_inf->vfork_parent = parent_inf; |
| 497 | child_inf->pending_detach = 0; |
| 498 | parent_inf->vfork_child = child_inf; |
| 499 | parent_inf->pending_detach = 0; |
| 500 | |
| 501 | /* Now that the inferiors and program spaces are all |
| 502 | wired up, we can switch to the child thread (which |
| 503 | switches inferior and program space too). */ |
| 504 | switch_to_thread (child_thr); |
| 505 | } |
| 506 | else |
| 507 | { |
| 508 | child_inf->aspace = new_address_space (); |
| 509 | child_inf->pspace = new program_space (child_inf->aspace); |
| 510 | child_inf->removable = 1; |
| 511 | set_current_program_space (child_inf->pspace); |
| 512 | clone_program_space (child_inf->pspace, parent_inf->pspace); |
| 513 | |
| 514 | /* solib_create_inferior_hook relies on the current |
| 515 | thread. */ |
| 516 | switch_to_thread (child_thr); |
| 517 | |
| 518 | /* Let the shared library layer (e.g., solib-svr4) learn |
| 519 | about this new process, relocate the cloned exec, pull |
| 520 | in shared libraries, and install the solib event |
| 521 | breakpoint. If a "cloned-VM" event was propagated |
| 522 | better throughout the core, this wouldn't be |
| 523 | required. */ |
| 524 | scoped_restore restore_in_initial_library_scan |
| 525 | = make_scoped_restore (&child_inf->in_initial_library_scan, |
| 526 | true); |
| 527 | solib_create_inferior_hook (0); |
| 528 | } |
| 529 | } |
| 530 | |
| 531 | if (has_vforked) |
| 532 | { |
| 533 | struct inferior *parent_inf; |
| 534 | |
| 535 | parent_inf = current_inferior (); |
| 536 | |
| 537 | /* If we detached from the child, then we have to be careful |
| 538 | to not insert breakpoints in the parent until the child |
| 539 | is done with the shared memory region. However, if we're |
| 540 | staying attached to the child, then we can and should |
| 541 | insert breakpoints, so that we can debug it. A |
| 542 | subsequent child exec or exit is enough to know when does |
| 543 | the child stops using the parent's address space. */ |
| 544 | parent_inf->waiting_for_vfork_done = detach_fork; |
| 545 | parent_inf->pspace->breakpoints_not_allowed = detach_fork; |
| 546 | } |
| 547 | } |
| 548 | else |
| 549 | { |
| 550 | /* Follow the child. */ |
| 551 | struct inferior *parent_inf, *child_inf; |
| 552 | struct program_space *parent_pspace; |
| 553 | |
| 554 | if (print_inferior_events) |
| 555 | { |
| 556 | std::string parent_pid = target_pid_to_str (parent_ptid); |
| 557 | std::string child_pid = target_pid_to_str (child_ptid); |
| 558 | |
| 559 | target_terminal::ours_for_output (); |
| 560 | fprintf_filtered (gdb_stdlog, |
| 561 | _("[Attaching after %s %s to child %s]\n"), |
| 562 | parent_pid.c_str (), |
| 563 | has_vforked ? "vfork" : "fork", |
| 564 | child_pid.c_str ()); |
| 565 | } |
| 566 | |
| 567 | /* Add the new inferior first, so that the target_detach below |
| 568 | doesn't unpush the target. */ |
| 569 | |
| 570 | child_inf = add_inferior (child_ptid.pid ()); |
| 571 | |
| 572 | parent_inf = current_inferior (); |
| 573 | child_inf->attach_flag = parent_inf->attach_flag; |
| 574 | copy_terminal_info (child_inf, parent_inf); |
| 575 | child_inf->gdbarch = parent_inf->gdbarch; |
| 576 | copy_inferior_target_desc_info (child_inf, parent_inf); |
| 577 | |
| 578 | parent_pspace = parent_inf->pspace; |
| 579 | |
| 580 | process_stratum_target *target = parent_inf->process_target (); |
| 581 | |
| 582 | { |
| 583 | /* Hold a strong reference to the target while (maybe) |
| 584 | detaching the parent. Otherwise detaching could close the |
| 585 | target. */ |
| 586 | auto target_ref = target_ops_ref::new_reference (target); |
| 587 | |
| 588 | /* If we're vforking, we want to hold on to the parent until |
| 589 | the child exits or execs. At child exec or exit time we |
| 590 | can remove the old breakpoints from the parent and detach |
| 591 | or resume debugging it. Otherwise, detach the parent now; |
| 592 | we'll want to reuse it's program/address spaces, but we |
| 593 | can't set them to the child before removing breakpoints |
| 594 | from the parent, otherwise, the breakpoints module could |
| 595 | decide to remove breakpoints from the wrong process (since |
| 596 | they'd be assigned to the same address space). */ |
| 597 | |
| 598 | if (has_vforked) |
| 599 | { |
| 600 | gdb_assert (child_inf->vfork_parent == NULL); |
| 601 | gdb_assert (parent_inf->vfork_child == NULL); |
| 602 | child_inf->vfork_parent = parent_inf; |
| 603 | child_inf->pending_detach = 0; |
| 604 | parent_inf->vfork_child = child_inf; |
| 605 | parent_inf->pending_detach = detach_fork; |
| 606 | parent_inf->waiting_for_vfork_done = 0; |
| 607 | } |
| 608 | else if (detach_fork) |
| 609 | { |
| 610 | if (print_inferior_events) |
| 611 | { |
| 612 | /* Ensure that we have a process ptid. */ |
| 613 | ptid_t process_ptid = ptid_t (parent_ptid.pid ()); |
| 614 | |
| 615 | target_terminal::ours_for_output (); |
| 616 | fprintf_filtered (gdb_stdlog, |
| 617 | _("[Detaching after fork from " |
| 618 | "parent %s]\n"), |
| 619 | target_pid_to_str (process_ptid).c_str ()); |
| 620 | } |
| 621 | |
| 622 | target_detach (parent_inf, 0); |
| 623 | parent_inf = NULL; |
| 624 | } |
| 625 | |
| 626 | /* Note that the detach above makes PARENT_INF dangling. */ |
| 627 | |
| 628 | /* Add the child thread to the appropriate lists, and switch |
| 629 | to this new thread, before cloning the program space, and |
| 630 | informing the solib layer about this new process. */ |
| 631 | |
| 632 | set_current_inferior (child_inf); |
| 633 | child_inf->push_target (target); |
| 634 | } |
| 635 | |
| 636 | thread_info *child_thr = add_thread_silent (target, child_ptid); |
| 637 | |
| 638 | /* If this is a vfork child, then the address-space is shared |
| 639 | with the parent. If we detached from the parent, then we can |
| 640 | reuse the parent's program/address spaces. */ |
| 641 | if (has_vforked || detach_fork) |
| 642 | { |
| 643 | child_inf->pspace = parent_pspace; |
| 644 | child_inf->aspace = child_inf->pspace->aspace; |
| 645 | |
| 646 | exec_on_vfork (); |
| 647 | } |
| 648 | else |
| 649 | { |
| 650 | child_inf->aspace = new_address_space (); |
| 651 | child_inf->pspace = new program_space (child_inf->aspace); |
| 652 | child_inf->removable = 1; |
| 653 | child_inf->symfile_flags = SYMFILE_NO_READ; |
| 654 | set_current_program_space (child_inf->pspace); |
| 655 | clone_program_space (child_inf->pspace, parent_pspace); |
| 656 | |
| 657 | /* Let the shared library layer (e.g., solib-svr4) learn |
| 658 | about this new process, relocate the cloned exec, pull in |
| 659 | shared libraries, and install the solib event breakpoint. |
| 660 | If a "cloned-VM" event was propagated better throughout |
| 661 | the core, this wouldn't be required. */ |
| 662 | scoped_restore restore_in_initial_library_scan |
| 663 | = make_scoped_restore (&child_inf->in_initial_library_scan, true); |
| 664 | solib_create_inferior_hook (0); |
| 665 | } |
| 666 | |
| 667 | switch_to_thread (child_thr); |
| 668 | } |
| 669 | |
| 670 | target_follow_fork (follow_child, detach_fork); |
| 671 | |
| 672 | return false; |
| 673 | } |
| 674 | |
| 675 | /* Tell the target to follow the fork we're stopped at. Returns true |
| 676 | if the inferior should be resumed; false, if the target for some |
| 677 | reason decided it's best not to resume. */ |
| 678 | |
| 679 | static bool |
| 680 | follow_fork () |
| 681 | { |
| 682 | bool follow_child = (follow_fork_mode_string == follow_fork_mode_child); |
| 683 | bool should_resume = true; |
| 684 | struct thread_info *tp; |
| 685 | |
| 686 | /* Copy user stepping state to the new inferior thread. FIXME: the |
| 687 | followed fork child thread should have a copy of most of the |
| 688 | parent thread structure's run control related fields, not just these. |
| 689 | Initialized to avoid "may be used uninitialized" warnings from gcc. */ |
| 690 | struct breakpoint *step_resume_breakpoint = NULL; |
| 691 | struct breakpoint *exception_resume_breakpoint = NULL; |
| 692 | CORE_ADDR step_range_start = 0; |
| 693 | CORE_ADDR step_range_end = 0; |
| 694 | int current_line = 0; |
| 695 | symtab *current_symtab = NULL; |
| 696 | struct frame_id step_frame_id = { 0 }; |
| 697 | struct thread_fsm *thread_fsm = NULL; |
| 698 | |
| 699 | if (!non_stop) |
| 700 | { |
| 701 | process_stratum_target *wait_target; |
| 702 | ptid_t wait_ptid; |
| 703 | struct target_waitstatus wait_status; |
| 704 | |
| 705 | /* Get the last target status returned by target_wait(). */ |
| 706 | get_last_target_status (&wait_target, &wait_ptid, &wait_status); |
| 707 | |
| 708 | /* If not stopped at a fork event, then there's nothing else to |
| 709 | do. */ |
| 710 | if (wait_status.kind != TARGET_WAITKIND_FORKED |
| 711 | && wait_status.kind != TARGET_WAITKIND_VFORKED) |
| 712 | return 1; |
| 713 | |
| 714 | /* Check if we switched over from WAIT_PTID, since the event was |
| 715 | reported. */ |
| 716 | if (wait_ptid != minus_one_ptid |
| 717 | && (current_inferior ()->process_target () != wait_target |
| 718 | || inferior_ptid != wait_ptid)) |
| 719 | { |
| 720 | /* We did. Switch back to WAIT_PTID thread, to tell the |
| 721 | target to follow it (in either direction). We'll |
| 722 | afterwards refuse to resume, and inform the user what |
| 723 | happened. */ |
| 724 | thread_info *wait_thread = find_thread_ptid (wait_target, wait_ptid); |
| 725 | switch_to_thread (wait_thread); |
| 726 | should_resume = false; |
| 727 | } |
| 728 | } |
| 729 | |
| 730 | tp = inferior_thread (); |
| 731 | |
| 732 | /* If there were any forks/vforks that were caught and are now to be |
| 733 | followed, then do so now. */ |
| 734 | switch (tp->pending_follow.kind) |
| 735 | { |
| 736 | case TARGET_WAITKIND_FORKED: |
| 737 | case TARGET_WAITKIND_VFORKED: |
| 738 | { |
| 739 | ptid_t parent, child; |
| 740 | |
| 741 | /* If the user did a next/step, etc, over a fork call, |
| 742 | preserve the stepping state in the fork child. */ |
| 743 | if (follow_child && should_resume) |
| 744 | { |
| 745 | step_resume_breakpoint = clone_momentary_breakpoint |
| 746 | (tp->control.step_resume_breakpoint); |
| 747 | step_range_start = tp->control.step_range_start; |
| 748 | step_range_end = tp->control.step_range_end; |
| 749 | current_line = tp->current_line; |
| 750 | current_symtab = tp->current_symtab; |
| 751 | step_frame_id = tp->control.step_frame_id; |
| 752 | exception_resume_breakpoint |
| 753 | = clone_momentary_breakpoint (tp->control.exception_resume_breakpoint); |
| 754 | thread_fsm = tp->thread_fsm; |
| 755 | |
| 756 | /* For now, delete the parent's sr breakpoint, otherwise, |
| 757 | parent/child sr breakpoints are considered duplicates, |
| 758 | and the child version will not be installed. Remove |
| 759 | this when the breakpoints module becomes aware of |
| 760 | inferiors and address spaces. */ |
| 761 | delete_step_resume_breakpoint (tp); |
| 762 | tp->control.step_range_start = 0; |
| 763 | tp->control.step_range_end = 0; |
| 764 | tp->control.step_frame_id = null_frame_id; |
| 765 | delete_exception_resume_breakpoint (tp); |
| 766 | tp->thread_fsm = NULL; |
| 767 | } |
| 768 | |
| 769 | parent = inferior_ptid; |
| 770 | child = tp->pending_follow.value.related_pid; |
| 771 | |
| 772 | process_stratum_target *parent_targ = tp->inf->process_target (); |
| 773 | /* Set up inferior(s) as specified by the caller, and tell the |
| 774 | target to do whatever is necessary to follow either parent |
| 775 | or child. */ |
| 776 | if (follow_fork_inferior (follow_child, detach_fork)) |
| 777 | { |
| 778 | /* Target refused to follow, or there's some other reason |
| 779 | we shouldn't resume. */ |
| 780 | should_resume = 0; |
| 781 | } |
| 782 | else |
| 783 | { |
| 784 | /* This pending follow fork event is now handled, one way |
| 785 | or another. The previous selected thread may be gone |
| 786 | from the lists by now, but if it is still around, need |
| 787 | to clear the pending follow request. */ |
| 788 | tp = find_thread_ptid (parent_targ, parent); |
| 789 | if (tp) |
| 790 | tp->pending_follow.kind = TARGET_WAITKIND_SPURIOUS; |
| 791 | |
| 792 | /* This makes sure we don't try to apply the "Switched |
| 793 | over from WAIT_PID" logic above. */ |
| 794 | nullify_last_target_wait_ptid (); |
| 795 | |
| 796 | /* If we followed the child, switch to it... */ |
| 797 | if (follow_child) |
| 798 | { |
| 799 | thread_info *child_thr = find_thread_ptid (parent_targ, child); |
| 800 | switch_to_thread (child_thr); |
| 801 | |
| 802 | /* ... and preserve the stepping state, in case the |
| 803 | user was stepping over the fork call. */ |
| 804 | if (should_resume) |
| 805 | { |
| 806 | tp = inferior_thread (); |
| 807 | tp->control.step_resume_breakpoint |
| 808 | = step_resume_breakpoint; |
| 809 | tp->control.step_range_start = step_range_start; |
| 810 | tp->control.step_range_end = step_range_end; |
| 811 | tp->current_line = current_line; |
| 812 | tp->current_symtab = current_symtab; |
| 813 | tp->control.step_frame_id = step_frame_id; |
| 814 | tp->control.exception_resume_breakpoint |
| 815 | = exception_resume_breakpoint; |
| 816 | tp->thread_fsm = thread_fsm; |
| 817 | } |
| 818 | else |
| 819 | { |
| 820 | /* If we get here, it was because we're trying to |
| 821 | resume from a fork catchpoint, but, the user |
| 822 | has switched threads away from the thread that |
| 823 | forked. In that case, the resume command |
| 824 | issued is most likely not applicable to the |
| 825 | child, so just warn, and refuse to resume. */ |
| 826 | warning (_("Not resuming: switched threads " |
| 827 | "before following fork child.")); |
| 828 | } |
| 829 | |
| 830 | /* Reset breakpoints in the child as appropriate. */ |
| 831 | follow_inferior_reset_breakpoints (); |
| 832 | } |
| 833 | } |
| 834 | } |
| 835 | break; |
| 836 | case TARGET_WAITKIND_SPURIOUS: |
| 837 | /* Nothing to follow. */ |
| 838 | break; |
| 839 | default: |
| 840 | internal_error (__FILE__, __LINE__, |
| 841 | "Unexpected pending_follow.kind %d\n", |
| 842 | tp->pending_follow.kind); |
| 843 | break; |
| 844 | } |
| 845 | |
| 846 | return should_resume; |
| 847 | } |
| 848 | |
| 849 | static void |
| 850 | follow_inferior_reset_breakpoints (void) |
| 851 | { |
| 852 | struct thread_info *tp = inferior_thread (); |
| 853 | |
| 854 | /* Was there a step_resume breakpoint? (There was if the user |
| 855 | did a "next" at the fork() call.) If so, explicitly reset its |
| 856 | thread number. Cloned step_resume breakpoints are disabled on |
| 857 | creation, so enable it here now that it is associated with the |
| 858 | correct thread. |
| 859 | |
| 860 | step_resumes are a form of bp that are made to be per-thread. |
| 861 | Since we created the step_resume bp when the parent process |
| 862 | was being debugged, and now are switching to the child process, |
| 863 | from the breakpoint package's viewpoint, that's a switch of |
| 864 | "threads". We must update the bp's notion of which thread |
| 865 | it is for, or it'll be ignored when it triggers. */ |
| 866 | |
| 867 | if (tp->control.step_resume_breakpoint) |
| 868 | { |
| 869 | breakpoint_re_set_thread (tp->control.step_resume_breakpoint); |
| 870 | tp->control.step_resume_breakpoint->loc->enabled = 1; |
| 871 | } |
| 872 | |
| 873 | /* Treat exception_resume breakpoints like step_resume breakpoints. */ |
| 874 | if (tp->control.exception_resume_breakpoint) |
| 875 | { |
| 876 | breakpoint_re_set_thread (tp->control.exception_resume_breakpoint); |
| 877 | tp->control.exception_resume_breakpoint->loc->enabled = 1; |
| 878 | } |
| 879 | |
| 880 | /* Reinsert all breakpoints in the child. The user may have set |
| 881 | breakpoints after catching the fork, in which case those |
| 882 | were never set in the child, but only in the parent. This makes |
| 883 | sure the inserted breakpoints match the breakpoint list. */ |
| 884 | |
| 885 | breakpoint_re_set (); |
| 886 | insert_breakpoints (); |
| 887 | } |
| 888 | |
| 889 | /* The child has exited or execed: resume threads of the parent the |
| 890 | user wanted to be executing. */ |
| 891 | |
| 892 | static int |
| 893 | proceed_after_vfork_done (struct thread_info *thread, |
| 894 | void *arg) |
| 895 | { |
| 896 | int pid = * (int *) arg; |
| 897 | |
| 898 | if (thread->ptid.pid () == pid |
| 899 | && thread->state == THREAD_RUNNING |
| 900 | && !thread->executing |
| 901 | && !thread->stop_requested |
| 902 | && thread->suspend.stop_signal == GDB_SIGNAL_0) |
| 903 | { |
| 904 | infrun_debug_printf ("resuming vfork parent thread %s", |
| 905 | target_pid_to_str (thread->ptid).c_str ()); |
| 906 | |
| 907 | switch_to_thread (thread); |
| 908 | clear_proceed_status (0); |
| 909 | proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT); |
| 910 | } |
| 911 | |
| 912 | return 0; |
| 913 | } |
| 914 | |
| 915 | /* Called whenever we notice an exec or exit event, to handle |
| 916 | detaching or resuming a vfork parent. */ |
| 917 | |
| 918 | static void |
| 919 | handle_vfork_child_exec_or_exit (int exec) |
| 920 | { |
| 921 | struct inferior *inf = current_inferior (); |
| 922 | |
| 923 | if (inf->vfork_parent) |
| 924 | { |
| 925 | int resume_parent = -1; |
| 926 | |
| 927 | /* This exec or exit marks the end of the shared memory region |
| 928 | between the parent and the child. Break the bonds. */ |
| 929 | inferior *vfork_parent = inf->vfork_parent; |
| 930 | inf->vfork_parent->vfork_child = NULL; |
| 931 | inf->vfork_parent = NULL; |
| 932 | |
| 933 | /* If the user wanted to detach from the parent, now is the |
| 934 | time. */ |
| 935 | if (vfork_parent->pending_detach) |
| 936 | { |
| 937 | struct program_space *pspace; |
| 938 | struct address_space *aspace; |
| 939 | |
| 940 | /* follow-fork child, detach-on-fork on. */ |
| 941 | |
| 942 | vfork_parent->pending_detach = 0; |
| 943 | |
| 944 | scoped_restore_current_pspace_and_thread restore_thread; |
| 945 | |
| 946 | /* We're letting loose of the parent. */ |
| 947 | thread_info *tp = any_live_thread_of_inferior (vfork_parent); |
| 948 | switch_to_thread (tp); |
| 949 | |
| 950 | /* We're about to detach from the parent, which implicitly |
| 951 | removes breakpoints from its address space. There's a |
| 952 | catch here: we want to reuse the spaces for the child, |
| 953 | but, parent/child are still sharing the pspace at this |
| 954 | point, although the exec in reality makes the kernel give |
| 955 | the child a fresh set of new pages. The problem here is |
| 956 | that the breakpoints module being unaware of this, would |
| 957 | likely chose the child process to write to the parent |
| 958 | address space. Swapping the child temporarily away from |
| 959 | the spaces has the desired effect. Yes, this is "sort |
| 960 | of" a hack. */ |
| 961 | |
| 962 | pspace = inf->pspace; |
| 963 | aspace = inf->aspace; |
| 964 | inf->aspace = NULL; |
| 965 | inf->pspace = NULL; |
| 966 | |
| 967 | if (print_inferior_events) |
| 968 | { |
| 969 | std::string pidstr |
| 970 | = target_pid_to_str (ptid_t (vfork_parent->pid)); |
| 971 | |
| 972 | target_terminal::ours_for_output (); |
| 973 | |
| 974 | if (exec) |
| 975 | { |
| 976 | fprintf_filtered (gdb_stdlog, |
| 977 | _("[Detaching vfork parent %s " |
| 978 | "after child exec]\n"), pidstr.c_str ()); |
| 979 | } |
| 980 | else |
| 981 | { |
| 982 | fprintf_filtered (gdb_stdlog, |
| 983 | _("[Detaching vfork parent %s " |
| 984 | "after child exit]\n"), pidstr.c_str ()); |
| 985 | } |
| 986 | } |
| 987 | |
| 988 | target_detach (vfork_parent, 0); |
| 989 | |
| 990 | /* Put it back. */ |
| 991 | inf->pspace = pspace; |
| 992 | inf->aspace = aspace; |
| 993 | } |
| 994 | else if (exec) |
| 995 | { |
| 996 | /* We're staying attached to the parent, so, really give the |
| 997 | child a new address space. */ |
| 998 | inf->pspace = new program_space (maybe_new_address_space ()); |
| 999 | inf->aspace = inf->pspace->aspace; |
| 1000 | inf->removable = 1; |
| 1001 | set_current_program_space (inf->pspace); |
| 1002 | |
| 1003 | resume_parent = vfork_parent->pid; |
| 1004 | } |
| 1005 | else |
| 1006 | { |
| 1007 | /* If this is a vfork child exiting, then the pspace and |
| 1008 | aspaces were shared with the parent. Since we're |
| 1009 | reporting the process exit, we'll be mourning all that is |
| 1010 | found in the address space, and switching to null_ptid, |
| 1011 | preparing to start a new inferior. But, since we don't |
| 1012 | want to clobber the parent's address/program spaces, we |
| 1013 | go ahead and create a new one for this exiting |
| 1014 | inferior. */ |
| 1015 | |
| 1016 | /* Switch to no-thread while running clone_program_space, so |
| 1017 | that clone_program_space doesn't want to read the |
| 1018 | selected frame of a dead process. */ |
| 1019 | scoped_restore_current_thread restore_thread; |
| 1020 | switch_to_no_thread (); |
| 1021 | |
| 1022 | inf->pspace = new program_space (maybe_new_address_space ()); |
| 1023 | inf->aspace = inf->pspace->aspace; |
| 1024 | set_current_program_space (inf->pspace); |
| 1025 | inf->removable = 1; |
| 1026 | inf->symfile_flags = SYMFILE_NO_READ; |
| 1027 | clone_program_space (inf->pspace, vfork_parent->pspace); |
| 1028 | |
| 1029 | resume_parent = vfork_parent->pid; |
| 1030 | } |
| 1031 | |
| 1032 | gdb_assert (current_program_space == inf->pspace); |
| 1033 | |
| 1034 | if (non_stop && resume_parent != -1) |
| 1035 | { |
| 1036 | /* If the user wanted the parent to be running, let it go |
| 1037 | free now. */ |
| 1038 | scoped_restore_current_thread restore_thread; |
| 1039 | |
| 1040 | infrun_debug_printf ("resuming vfork parent process %d", |
| 1041 | resume_parent); |
| 1042 | |
| 1043 | iterate_over_threads (proceed_after_vfork_done, &resume_parent); |
| 1044 | } |
| 1045 | } |
| 1046 | } |
| 1047 | |
| 1048 | /* Enum strings for "set|show follow-exec-mode". */ |
| 1049 | |
| 1050 | static const char follow_exec_mode_new[] = "new"; |
| 1051 | static const char follow_exec_mode_same[] = "same"; |
| 1052 | static const char *const follow_exec_mode_names[] = |
| 1053 | { |
| 1054 | follow_exec_mode_new, |
| 1055 | follow_exec_mode_same, |
| 1056 | NULL, |
| 1057 | }; |
| 1058 | |
| 1059 | static const char *follow_exec_mode_string = follow_exec_mode_same; |
| 1060 | static void |
| 1061 | show_follow_exec_mode_string (struct ui_file *file, int from_tty, |
| 1062 | struct cmd_list_element *c, const char *value) |
| 1063 | { |
| 1064 | fprintf_filtered (file, _("Follow exec mode is \"%s\".\n"), value); |
| 1065 | } |
| 1066 | |
| 1067 | /* EXEC_FILE_TARGET is assumed to be non-NULL. */ |
| 1068 | |
| 1069 | static void |
| 1070 | follow_exec (ptid_t ptid, const char *exec_file_target) |
| 1071 | { |
| 1072 | int pid = ptid.pid (); |
| 1073 | ptid_t process_ptid; |
| 1074 | |
| 1075 | /* Switch terminal for any messages produced e.g. by |
| 1076 | breakpoint_re_set. */ |
| 1077 | target_terminal::ours_for_output (); |
| 1078 | |
| 1079 | /* This is an exec event that we actually wish to pay attention to. |
| 1080 | Refresh our symbol table to the newly exec'd program, remove any |
| 1081 | momentary bp's, etc. |
| 1082 | |
| 1083 | If there are breakpoints, they aren't really inserted now, |
| 1084 | since the exec() transformed our inferior into a fresh set |
| 1085 | of instructions. |
| 1086 | |
| 1087 | We want to preserve symbolic breakpoints on the list, since |
| 1088 | we have hopes that they can be reset after the new a.out's |
| 1089 | symbol table is read. |
| 1090 | |
| 1091 | However, any "raw" breakpoints must be removed from the list |
| 1092 | (e.g., the solib bp's), since their address is probably invalid |
| 1093 | now. |
| 1094 | |
| 1095 | And, we DON'T want to call delete_breakpoints() here, since |
| 1096 | that may write the bp's "shadow contents" (the instruction |
| 1097 | value that was overwritten with a TRAP instruction). Since |
| 1098 | we now have a new a.out, those shadow contents aren't valid. */ |
| 1099 | |
| 1100 | mark_breakpoints_out (); |
| 1101 | |
| 1102 | /* The target reports the exec event to the main thread, even if |
| 1103 | some other thread does the exec, and even if the main thread was |
| 1104 | stopped or already gone. We may still have non-leader threads of |
| 1105 | the process on our list. E.g., on targets that don't have thread |
| 1106 | exit events (like remote); or on native Linux in non-stop mode if |
| 1107 | there were only two threads in the inferior and the non-leader |
| 1108 | one is the one that execs (and nothing forces an update of the |
| 1109 | thread list up to here). When debugging remotely, it's best to |
| 1110 | avoid extra traffic, when possible, so avoid syncing the thread |
| 1111 | list with the target, and instead go ahead and delete all threads |
| 1112 | of the process but one that reported the event. Note this must |
| 1113 | be done before calling update_breakpoints_after_exec, as |
| 1114 | otherwise clearing the threads' resources would reference stale |
| 1115 | thread breakpoints -- it may have been one of these threads that |
| 1116 | stepped across the exec. We could just clear their stepping |
| 1117 | states, but as long as we're iterating, might as well delete |
| 1118 | them. Deleting them now rather than at the next user-visible |
| 1119 | stop provides a nicer sequence of events for user and MI |
| 1120 | notifications. */ |
| 1121 | for (thread_info *th : all_threads_safe ()) |
| 1122 | if (th->ptid.pid () == pid && th->ptid != ptid) |
| 1123 | delete_thread (th); |
| 1124 | |
| 1125 | /* We also need to clear any left over stale state for the |
| 1126 | leader/event thread. E.g., if there was any step-resume |
| 1127 | breakpoint or similar, it's gone now. We cannot truly |
| 1128 | step-to-next statement through an exec(). */ |
| 1129 | thread_info *th = inferior_thread (); |
| 1130 | th->control.step_resume_breakpoint = NULL; |
| 1131 | th->control.exception_resume_breakpoint = NULL; |
| 1132 | th->control.single_step_breakpoints = NULL; |
| 1133 | th->control.step_range_start = 0; |
| 1134 | th->control.step_range_end = 0; |
| 1135 | |
| 1136 | /* The user may have had the main thread held stopped in the |
| 1137 | previous image (e.g., schedlock on, or non-stop). Release |
| 1138 | it now. */ |
| 1139 | th->stop_requested = 0; |
| 1140 | |
| 1141 | update_breakpoints_after_exec (); |
| 1142 | |
| 1143 | /* What is this a.out's name? */ |
| 1144 | process_ptid = ptid_t (pid); |
| 1145 | printf_unfiltered (_("%s is executing new program: %s\n"), |
| 1146 | target_pid_to_str (process_ptid).c_str (), |
| 1147 | exec_file_target); |
| 1148 | |
| 1149 | /* We've followed the inferior through an exec. Therefore, the |
| 1150 | inferior has essentially been killed & reborn. */ |
| 1151 | |
| 1152 | breakpoint_init_inferior (inf_execd); |
| 1153 | |
| 1154 | gdb::unique_xmalloc_ptr<char> exec_file_host |
| 1155 | = exec_file_find (exec_file_target, NULL); |
| 1156 | |
| 1157 | /* If we were unable to map the executable target pathname onto a host |
| 1158 | pathname, tell the user that. Otherwise GDB's subsequent behavior |
| 1159 | is confusing. Maybe it would even be better to stop at this point |
| 1160 | so that the user can specify a file manually before continuing. */ |
| 1161 | if (exec_file_host == NULL) |
| 1162 | warning (_("Could not load symbols for executable %s.\n" |
| 1163 | "Do you need \"set sysroot\"?"), |
| 1164 | exec_file_target); |
| 1165 | |
| 1166 | /* Reset the shared library package. This ensures that we get a |
| 1167 | shlib event when the child reaches "_start", at which point the |
| 1168 | dld will have had a chance to initialize the child. */ |
| 1169 | /* Also, loading a symbol file below may trigger symbol lookups, and |
| 1170 | we don't want those to be satisfied by the libraries of the |
| 1171 | previous incarnation of this process. */ |
| 1172 | no_shared_libraries (NULL, 0); |
| 1173 | |
| 1174 | struct inferior *inf = current_inferior (); |
| 1175 | |
| 1176 | if (follow_exec_mode_string == follow_exec_mode_new) |
| 1177 | { |
| 1178 | /* The user wants to keep the old inferior and program spaces |
| 1179 | around. Create a new fresh one, and switch to it. */ |
| 1180 | |
| 1181 | /* Do exit processing for the original inferior before setting the new |
| 1182 | inferior's pid. Having two inferiors with the same pid would confuse |
| 1183 | find_inferior_p(t)id. Transfer the terminal state and info from the |
| 1184 | old to the new inferior. */ |
| 1185 | inferior *new_inferior = add_inferior_with_spaces (); |
| 1186 | |
| 1187 | swap_terminal_info (new_inferior, inf); |
| 1188 | exit_inferior_silent (inf); |
| 1189 | |
| 1190 | new_inferior->pid = pid; |
| 1191 | target_follow_exec (new_inferior, ptid, exec_file_target); |
| 1192 | |
| 1193 | /* We continue with the new inferior. */ |
| 1194 | inf = new_inferior; |
| 1195 | } |
| 1196 | else |
| 1197 | { |
| 1198 | /* The old description may no longer be fit for the new image. |
| 1199 | E.g, a 64-bit process exec'ed a 32-bit process. Clear the |
| 1200 | old description; we'll read a new one below. No need to do |
| 1201 | this on "follow-exec-mode new", as the old inferior stays |
| 1202 | around (its description is later cleared/refetched on |
| 1203 | restart). */ |
| 1204 | target_clear_description (); |
| 1205 | target_follow_exec (inf, ptid, exec_file_target); |
| 1206 | } |
| 1207 | |
| 1208 | gdb_assert (current_inferior () == inf); |
| 1209 | gdb_assert (current_program_space == inf->pspace); |
| 1210 | |
| 1211 | /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used |
| 1212 | because the proper displacement for a PIE (Position Independent |
| 1213 | Executable) main symbol file will only be computed by |
| 1214 | solib_create_inferior_hook below. breakpoint_re_set would fail |
| 1215 | to insert the breakpoints with the zero displacement. */ |
| 1216 | try_open_exec_file (exec_file_host.get (), inf, SYMFILE_DEFER_BP_RESET); |
| 1217 | |
| 1218 | /* If the target can specify a description, read it. Must do this |
| 1219 | after flipping to the new executable (because the target supplied |
| 1220 | description must be compatible with the executable's |
| 1221 | architecture, and the old executable may e.g., be 32-bit, while |
| 1222 | the new one 64-bit), and before anything involving memory or |
| 1223 | registers. */ |
| 1224 | target_find_description (); |
| 1225 | |
| 1226 | gdb::observers::inferior_execd.notify (inf); |
| 1227 | |
| 1228 | breakpoint_re_set (); |
| 1229 | |
| 1230 | /* Reinsert all breakpoints. (Those which were symbolic have |
| 1231 | been reset to the proper address in the new a.out, thanks |
| 1232 | to symbol_file_command...). */ |
| 1233 | insert_breakpoints (); |
| 1234 | |
| 1235 | /* The next resume of this inferior should bring it to the shlib |
| 1236 | startup breakpoints. (If the user had also set bp's on |
| 1237 | "main" from the old (parent) process, then they'll auto- |
| 1238 | matically get reset there in the new process.). */ |
| 1239 | } |
| 1240 | |
| 1241 | /* The chain of threads that need to do a step-over operation to get |
| 1242 | past e.g., a breakpoint. What technique is used to step over the |
| 1243 | breakpoint/watchpoint does not matter -- all threads end up in the |
| 1244 | same queue, to maintain rough temporal order of execution, in order |
| 1245 | to avoid starvation, otherwise, we could e.g., find ourselves |
| 1246 | constantly stepping the same couple threads past their breakpoints |
| 1247 | over and over, if the single-step finish fast enough. */ |
| 1248 | struct thread_info *global_thread_step_over_chain_head; |
| 1249 | |
| 1250 | /* Bit flags indicating what the thread needs to step over. */ |
| 1251 | |
| 1252 | enum step_over_what_flag |
| 1253 | { |
| 1254 | /* Step over a breakpoint. */ |
| 1255 | STEP_OVER_BREAKPOINT = 1, |
| 1256 | |
| 1257 | /* Step past a non-continuable watchpoint, in order to let the |
| 1258 | instruction execute so we can evaluate the watchpoint |
| 1259 | expression. */ |
| 1260 | STEP_OVER_WATCHPOINT = 2 |
| 1261 | }; |
| 1262 | DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag, step_over_what); |
| 1263 | |
| 1264 | /* Info about an instruction that is being stepped over. */ |
| 1265 | |
| 1266 | struct step_over_info |
| 1267 | { |
| 1268 | /* If we're stepping past a breakpoint, this is the address space |
| 1269 | and address of the instruction the breakpoint is set at. We'll |
| 1270 | skip inserting all breakpoints here. Valid iff ASPACE is |
| 1271 | non-NULL. */ |
| 1272 | const address_space *aspace = nullptr; |
| 1273 | CORE_ADDR address = 0; |
| 1274 | |
| 1275 | /* The instruction being stepped over triggers a nonsteppable |
| 1276 | watchpoint. If true, we'll skip inserting watchpoints. */ |
| 1277 | int nonsteppable_watchpoint_p = 0; |
| 1278 | |
| 1279 | /* The thread's global number. */ |
| 1280 | int thread = -1; |
| 1281 | }; |
| 1282 | |
| 1283 | /* The step-over info of the location that is being stepped over. |
| 1284 | |
| 1285 | Note that with async/breakpoint always-inserted mode, a user might |
| 1286 | set a new breakpoint/watchpoint/etc. exactly while a breakpoint is |
| 1287 | being stepped over. As setting a new breakpoint inserts all |
| 1288 | breakpoints, we need to make sure the breakpoint being stepped over |
| 1289 | isn't inserted then. We do that by only clearing the step-over |
| 1290 | info when the step-over is actually finished (or aborted). |
| 1291 | |
| 1292 | Presently GDB can only step over one breakpoint at any given time. |
| 1293 | Given threads that can't run code in the same address space as the |
| 1294 | breakpoint's can't really miss the breakpoint, GDB could be taught |
| 1295 | to step-over at most one breakpoint per address space (so this info |
| 1296 | could move to the address space object if/when GDB is extended). |
| 1297 | The set of breakpoints being stepped over will normally be much |
| 1298 | smaller than the set of all breakpoints, so a flag in the |
| 1299 | breakpoint location structure would be wasteful. A separate list |
| 1300 | also saves complexity and run-time, as otherwise we'd have to go |
| 1301 | through all breakpoint locations clearing their flag whenever we |
| 1302 | start a new sequence. Similar considerations weigh against storing |
| 1303 | this info in the thread object. Plus, not all step overs actually |
| 1304 | have breakpoint locations -- e.g., stepping past a single-step |
| 1305 | breakpoint, or stepping to complete a non-continuable |
| 1306 | watchpoint. */ |
| 1307 | static struct step_over_info step_over_info; |
| 1308 | |
| 1309 | /* Record the address of the breakpoint/instruction we're currently |
| 1310 | stepping over. |
| 1311 | N.B. We record the aspace and address now, instead of say just the thread, |
| 1312 | because when we need the info later the thread may be running. */ |
| 1313 | |
| 1314 | static void |
| 1315 | set_step_over_info (const address_space *aspace, CORE_ADDR address, |
| 1316 | int nonsteppable_watchpoint_p, |
| 1317 | int thread) |
| 1318 | { |
| 1319 | step_over_info.aspace = aspace; |
| 1320 | step_over_info.address = address; |
| 1321 | step_over_info.nonsteppable_watchpoint_p = nonsteppable_watchpoint_p; |
| 1322 | step_over_info.thread = thread; |
| 1323 | } |
| 1324 | |
| 1325 | /* Called when we're not longer stepping over a breakpoint / an |
| 1326 | instruction, so all breakpoints are free to be (re)inserted. */ |
| 1327 | |
| 1328 | static void |
| 1329 | clear_step_over_info (void) |
| 1330 | { |
| 1331 | infrun_debug_printf ("clearing step over info"); |
| 1332 | step_over_info.aspace = NULL; |
| 1333 | step_over_info.address = 0; |
| 1334 | step_over_info.nonsteppable_watchpoint_p = 0; |
| 1335 | step_over_info.thread = -1; |
| 1336 | } |
| 1337 | |
| 1338 | /* See infrun.h. */ |
| 1339 | |
| 1340 | int |
| 1341 | stepping_past_instruction_at (struct address_space *aspace, |
| 1342 | CORE_ADDR address) |
| 1343 | { |
| 1344 | return (step_over_info.aspace != NULL |
| 1345 | && breakpoint_address_match (aspace, address, |
| 1346 | step_over_info.aspace, |
| 1347 | step_over_info.address)); |
| 1348 | } |
| 1349 | |
| 1350 | /* See infrun.h. */ |
| 1351 | |
| 1352 | int |
| 1353 | thread_is_stepping_over_breakpoint (int thread) |
| 1354 | { |
| 1355 | return (step_over_info.thread != -1 |
| 1356 | && thread == step_over_info.thread); |
| 1357 | } |
| 1358 | |
| 1359 | /* See infrun.h. */ |
| 1360 | |
| 1361 | int |
| 1362 | stepping_past_nonsteppable_watchpoint (void) |
| 1363 | { |
| 1364 | return step_over_info.nonsteppable_watchpoint_p; |
| 1365 | } |
| 1366 | |
| 1367 | /* Returns true if step-over info is valid. */ |
| 1368 | |
| 1369 | static bool |
| 1370 | step_over_info_valid_p (void) |
| 1371 | { |
| 1372 | return (step_over_info.aspace != NULL |
| 1373 | || stepping_past_nonsteppable_watchpoint ()); |
| 1374 | } |
| 1375 | |
| 1376 | \f |
| 1377 | /* Displaced stepping. */ |
| 1378 | |
| 1379 | /* In non-stop debugging mode, we must take special care to manage |
| 1380 | breakpoints properly; in particular, the traditional strategy for |
| 1381 | stepping a thread past a breakpoint it has hit is unsuitable. |
| 1382 | 'Displaced stepping' is a tactic for stepping one thread past a |
| 1383 | breakpoint it has hit while ensuring that other threads running |
| 1384 | concurrently will hit the breakpoint as they should. |
| 1385 | |
| 1386 | The traditional way to step a thread T off a breakpoint in a |
| 1387 | multi-threaded program in all-stop mode is as follows: |
| 1388 | |
| 1389 | a0) Initially, all threads are stopped, and breakpoints are not |
| 1390 | inserted. |
| 1391 | a1) We single-step T, leaving breakpoints uninserted. |
| 1392 | a2) We insert breakpoints, and resume all threads. |
| 1393 | |
| 1394 | In non-stop debugging, however, this strategy is unsuitable: we |
| 1395 | don't want to have to stop all threads in the system in order to |
| 1396 | continue or step T past a breakpoint. Instead, we use displaced |
| 1397 | stepping: |
| 1398 | |
| 1399 | n0) Initially, T is stopped, other threads are running, and |
| 1400 | breakpoints are inserted. |
| 1401 | n1) We copy the instruction "under" the breakpoint to a separate |
| 1402 | location, outside the main code stream, making any adjustments |
| 1403 | to the instruction, register, and memory state as directed by |
| 1404 | T's architecture. |
| 1405 | n2) We single-step T over the instruction at its new location. |
| 1406 | n3) We adjust the resulting register and memory state as directed |
| 1407 | by T's architecture. This includes resetting T's PC to point |
| 1408 | back into the main instruction stream. |
| 1409 | n4) We resume T. |
| 1410 | |
| 1411 | This approach depends on the following gdbarch methods: |
| 1412 | |
| 1413 | - gdbarch_max_insn_length and gdbarch_displaced_step_location |
| 1414 | indicate where to copy the instruction, and how much space must |
| 1415 | be reserved there. We use these in step n1. |
| 1416 | |
| 1417 | - gdbarch_displaced_step_copy_insn copies a instruction to a new |
| 1418 | address, and makes any necessary adjustments to the instruction, |
| 1419 | register contents, and memory. We use this in step n1. |
| 1420 | |
| 1421 | - gdbarch_displaced_step_fixup adjusts registers and memory after |
| 1422 | we have successfully single-stepped the instruction, to yield the |
| 1423 | same effect the instruction would have had if we had executed it |
| 1424 | at its original address. We use this in step n3. |
| 1425 | |
| 1426 | The gdbarch_displaced_step_copy_insn and |
| 1427 | gdbarch_displaced_step_fixup functions must be written so that |
| 1428 | copying an instruction with gdbarch_displaced_step_copy_insn, |
| 1429 | single-stepping across the copied instruction, and then applying |
| 1430 | gdbarch_displaced_insn_fixup should have the same effects on the |
| 1431 | thread's memory and registers as stepping the instruction in place |
| 1432 | would have. Exactly which responsibilities fall to the copy and |
| 1433 | which fall to the fixup is up to the author of those functions. |
| 1434 | |
| 1435 | See the comments in gdbarch.sh for details. |
| 1436 | |
| 1437 | Note that displaced stepping and software single-step cannot |
| 1438 | currently be used in combination, although with some care I think |
| 1439 | they could be made to. Software single-step works by placing |
| 1440 | breakpoints on all possible subsequent instructions; if the |
| 1441 | displaced instruction is a PC-relative jump, those breakpoints |
| 1442 | could fall in very strange places --- on pages that aren't |
| 1443 | executable, or at addresses that are not proper instruction |
| 1444 | boundaries. (We do generally let other threads run while we wait |
| 1445 | to hit the software single-step breakpoint, and they might |
| 1446 | encounter such a corrupted instruction.) One way to work around |
| 1447 | this would be to have gdbarch_displaced_step_copy_insn fully |
| 1448 | simulate the effect of PC-relative instructions (and return NULL) |
| 1449 | on architectures that use software single-stepping. |
| 1450 | |
| 1451 | In non-stop mode, we can have independent and simultaneous step |
| 1452 | requests, so more than one thread may need to simultaneously step |
| 1453 | over a breakpoint. The current implementation assumes there is |
| 1454 | only one scratch space per process. In this case, we have to |
| 1455 | serialize access to the scratch space. If thread A wants to step |
| 1456 | over a breakpoint, but we are currently waiting for some other |
| 1457 | thread to complete a displaced step, we leave thread A stopped and |
| 1458 | place it in the displaced_step_request_queue. Whenever a displaced |
| 1459 | step finishes, we pick the next thread in the queue and start a new |
| 1460 | displaced step operation on it. See displaced_step_prepare and |
| 1461 | displaced_step_finish for details. */ |
| 1462 | |
| 1463 | /* Return true if THREAD is doing a displaced step. */ |
| 1464 | |
| 1465 | static bool |
| 1466 | displaced_step_in_progress_thread (thread_info *thread) |
| 1467 | { |
| 1468 | gdb_assert (thread != NULL); |
| 1469 | |
| 1470 | return thread->displaced_step_state.in_progress (); |
| 1471 | } |
| 1472 | |
| 1473 | /* Return true if INF has a thread doing a displaced step. */ |
| 1474 | |
| 1475 | static bool |
| 1476 | displaced_step_in_progress (inferior *inf) |
| 1477 | { |
| 1478 | return inf->displaced_step_state.in_progress_count > 0; |
| 1479 | } |
| 1480 | |
| 1481 | /* Return true if any thread is doing a displaced step. */ |
| 1482 | |
| 1483 | static bool |
| 1484 | displaced_step_in_progress_any_thread () |
| 1485 | { |
| 1486 | for (inferior *inf : all_non_exited_inferiors ()) |
| 1487 | { |
| 1488 | if (displaced_step_in_progress (inf)) |
| 1489 | return true; |
| 1490 | } |
| 1491 | |
| 1492 | return false; |
| 1493 | } |
| 1494 | |
| 1495 | static void |
| 1496 | infrun_inferior_exit (struct inferior *inf) |
| 1497 | { |
| 1498 | inf->displaced_step_state.reset (); |
| 1499 | } |
| 1500 | |
| 1501 | static void |
| 1502 | infrun_inferior_execd (inferior *inf) |
| 1503 | { |
| 1504 | /* If some threads where was doing a displaced step in this inferior at the |
| 1505 | moment of the exec, they no longer exist. Even if the exec'ing thread |
| 1506 | doing a displaced step, we don't want to to any fixup nor restore displaced |
| 1507 | stepping buffer bytes. */ |
| 1508 | inf->displaced_step_state.reset (); |
| 1509 | |
| 1510 | for (thread_info *thread : inf->threads ()) |
| 1511 | thread->displaced_step_state.reset (); |
| 1512 | |
| 1513 | /* Since an in-line step is done with everything else stopped, if there was |
| 1514 | one in progress at the time of the exec, it must have been the exec'ing |
| 1515 | thread. */ |
| 1516 | clear_step_over_info (); |
| 1517 | } |
| 1518 | |
| 1519 | /* If ON, and the architecture supports it, GDB will use displaced |
| 1520 | stepping to step over breakpoints. If OFF, or if the architecture |
| 1521 | doesn't support it, GDB will instead use the traditional |
| 1522 | hold-and-step approach. If AUTO (which is the default), GDB will |
| 1523 | decide which technique to use to step over breakpoints depending on |
| 1524 | whether the target works in a non-stop way (see use_displaced_stepping). */ |
| 1525 | |
| 1526 | static enum auto_boolean can_use_displaced_stepping = AUTO_BOOLEAN_AUTO; |
| 1527 | |
| 1528 | static void |
| 1529 | show_can_use_displaced_stepping (struct ui_file *file, int from_tty, |
| 1530 | struct cmd_list_element *c, |
| 1531 | const char *value) |
| 1532 | { |
| 1533 | if (can_use_displaced_stepping == AUTO_BOOLEAN_AUTO) |
| 1534 | fprintf_filtered (file, |
| 1535 | _("Debugger's willingness to use displaced stepping " |
| 1536 | "to step over breakpoints is %s (currently %s).\n"), |
| 1537 | value, target_is_non_stop_p () ? "on" : "off"); |
| 1538 | else |
| 1539 | fprintf_filtered (file, |
| 1540 | _("Debugger's willingness to use displaced stepping " |
| 1541 | "to step over breakpoints is %s.\n"), value); |
| 1542 | } |
| 1543 | |
| 1544 | /* Return true if the gdbarch implements the required methods to use |
| 1545 | displaced stepping. */ |
| 1546 | |
| 1547 | static bool |
| 1548 | gdbarch_supports_displaced_stepping (gdbarch *arch) |
| 1549 | { |
| 1550 | /* Only check for the presence of `prepare`. The gdbarch verification ensures |
| 1551 | that if `prepare` is provided, so is `finish`. */ |
| 1552 | return gdbarch_displaced_step_prepare_p (arch); |
| 1553 | } |
| 1554 | |
| 1555 | /* Return non-zero if displaced stepping can/should be used to step |
| 1556 | over breakpoints of thread TP. */ |
| 1557 | |
| 1558 | static bool |
| 1559 | use_displaced_stepping (thread_info *tp) |
| 1560 | { |
| 1561 | /* If the user disabled it explicitly, don't use displaced stepping. */ |
| 1562 | if (can_use_displaced_stepping == AUTO_BOOLEAN_FALSE) |
| 1563 | return false; |
| 1564 | |
| 1565 | /* If "auto", only use displaced stepping if the target operates in a non-stop |
| 1566 | way. */ |
| 1567 | if (can_use_displaced_stepping == AUTO_BOOLEAN_AUTO |
| 1568 | && !target_is_non_stop_p ()) |
| 1569 | return false; |
| 1570 | |
| 1571 | gdbarch *gdbarch = get_thread_regcache (tp)->arch (); |
| 1572 | |
| 1573 | /* If the architecture doesn't implement displaced stepping, don't use |
| 1574 | it. */ |
| 1575 | if (!gdbarch_supports_displaced_stepping (gdbarch)) |
| 1576 | return false; |
| 1577 | |
| 1578 | /* If recording, don't use displaced stepping. */ |
| 1579 | if (find_record_target () != nullptr) |
| 1580 | return false; |
| 1581 | |
| 1582 | /* If displaced stepping failed before for this inferior, don't bother trying |
| 1583 | again. */ |
| 1584 | if (tp->inf->displaced_step_state.failed_before) |
| 1585 | return false; |
| 1586 | |
| 1587 | return true; |
| 1588 | } |
| 1589 | |
| 1590 | /* Simple function wrapper around displaced_step_thread_state::reset. */ |
| 1591 | |
| 1592 | static void |
| 1593 | displaced_step_reset (displaced_step_thread_state *displaced) |
| 1594 | { |
| 1595 | displaced->reset (); |
| 1596 | } |
| 1597 | |
| 1598 | /* A cleanup that wraps displaced_step_reset. We use this instead of, say, |
| 1599 | SCOPE_EXIT, because it needs to be discardable with "cleanup.release ()". */ |
| 1600 | |
| 1601 | using displaced_step_reset_cleanup = FORWARD_SCOPE_EXIT (displaced_step_reset); |
| 1602 | |
| 1603 | /* See infrun.h. */ |
| 1604 | |
| 1605 | std::string |
| 1606 | displaced_step_dump_bytes (const gdb_byte *buf, size_t len) |
| 1607 | { |
| 1608 | std::string ret; |
| 1609 | |
| 1610 | for (size_t i = 0; i < len; i++) |
| 1611 | { |
| 1612 | if (i == 0) |
| 1613 | ret += string_printf ("%02x", buf[i]); |
| 1614 | else |
| 1615 | ret += string_printf (" %02x", buf[i]); |
| 1616 | } |
| 1617 | |
| 1618 | return ret; |
| 1619 | } |
| 1620 | |
| 1621 | /* Prepare to single-step, using displaced stepping. |
| 1622 | |
| 1623 | Note that we cannot use displaced stepping when we have a signal to |
| 1624 | deliver. If we have a signal to deliver and an instruction to step |
| 1625 | over, then after the step, there will be no indication from the |
| 1626 | target whether the thread entered a signal handler or ignored the |
| 1627 | signal and stepped over the instruction successfully --- both cases |
| 1628 | result in a simple SIGTRAP. In the first case we mustn't do a |
| 1629 | fixup, and in the second case we must --- but we can't tell which. |
| 1630 | Comments in the code for 'random signals' in handle_inferior_event |
| 1631 | explain how we handle this case instead. |
| 1632 | |
| 1633 | Returns DISPLACED_STEP_PREPARE_STATUS_OK if preparing was successful -- this |
| 1634 | thread is going to be stepped now; DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE |
| 1635 | if displaced stepping this thread got queued; or |
| 1636 | DISPLACED_STEP_PREPARE_STATUS_CANT if this instruction can't be displaced |
| 1637 | stepped. */ |
| 1638 | |
| 1639 | static displaced_step_prepare_status |
| 1640 | displaced_step_prepare_throw (thread_info *tp) |
| 1641 | { |
| 1642 | regcache *regcache = get_thread_regcache (tp); |
| 1643 | struct gdbarch *gdbarch = regcache->arch (); |
| 1644 | displaced_step_thread_state &disp_step_thread_state |
| 1645 | = tp->displaced_step_state; |
| 1646 | |
| 1647 | /* We should never reach this function if the architecture does not |
| 1648 | support displaced stepping. */ |
| 1649 | gdb_assert (gdbarch_supports_displaced_stepping (gdbarch)); |
| 1650 | |
| 1651 | /* Nor if the thread isn't meant to step over a breakpoint. */ |
| 1652 | gdb_assert (tp->control.trap_expected); |
| 1653 | |
| 1654 | /* Disable range stepping while executing in the scratch pad. We |
| 1655 | want a single-step even if executing the displaced instruction in |
| 1656 | the scratch buffer lands within the stepping range (e.g., a |
| 1657 | jump/branch). */ |
| 1658 | tp->control.may_range_step = 0; |
| 1659 | |
| 1660 | /* We are about to start a displaced step for this thread. If one is already |
| 1661 | in progress, something's wrong. */ |
| 1662 | gdb_assert (!disp_step_thread_state.in_progress ()); |
| 1663 | |
| 1664 | if (tp->inf->displaced_step_state.unavailable) |
| 1665 | { |
| 1666 | /* The gdbarch tells us it's not worth asking to try a prepare because |
| 1667 | it is likely that it will return unavailable, so don't bother asking. */ |
| 1668 | |
| 1669 | displaced_debug_printf ("deferring step of %s", |
| 1670 | target_pid_to_str (tp->ptid).c_str ()); |
| 1671 | |
| 1672 | global_thread_step_over_chain_enqueue (tp); |
| 1673 | return DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE; |
| 1674 | } |
| 1675 | |
| 1676 | displaced_debug_printf ("displaced-stepping %s now", |
| 1677 | target_pid_to_str (tp->ptid).c_str ()); |
| 1678 | |
| 1679 | scoped_restore_current_thread restore_thread; |
| 1680 | |
| 1681 | switch_to_thread (tp); |
| 1682 | |
| 1683 | CORE_ADDR original_pc = regcache_read_pc (regcache); |
| 1684 | CORE_ADDR displaced_pc; |
| 1685 | |
| 1686 | displaced_step_prepare_status status |
| 1687 | = gdbarch_displaced_step_prepare (gdbarch, tp, displaced_pc); |
| 1688 | |
| 1689 | if (status == DISPLACED_STEP_PREPARE_STATUS_CANT) |
| 1690 | { |
| 1691 | displaced_debug_printf ("failed to prepare (%s)", |
| 1692 | target_pid_to_str (tp->ptid).c_str ()); |
| 1693 | |
| 1694 | return DISPLACED_STEP_PREPARE_STATUS_CANT; |
| 1695 | } |
| 1696 | else if (status == DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE) |
| 1697 | { |
| 1698 | /* Not enough displaced stepping resources available, defer this |
| 1699 | request by placing it the queue. */ |
| 1700 | |
| 1701 | displaced_debug_printf ("not enough resources available, " |
| 1702 | "deferring step of %s", |
| 1703 | target_pid_to_str (tp->ptid).c_str ()); |
| 1704 | |
| 1705 | global_thread_step_over_chain_enqueue (tp); |
| 1706 | |
| 1707 | return DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE; |
| 1708 | } |
| 1709 | |
| 1710 | gdb_assert (status == DISPLACED_STEP_PREPARE_STATUS_OK); |
| 1711 | |
| 1712 | /* Save the information we need to fix things up if the step |
| 1713 | succeeds. */ |
| 1714 | disp_step_thread_state.set (gdbarch); |
| 1715 | |
| 1716 | tp->inf->displaced_step_state.in_progress_count++; |
| 1717 | |
| 1718 | displaced_debug_printf ("prepared successfully thread=%s, " |
| 1719 | "original_pc=%s, displaced_pc=%s", |
| 1720 | target_pid_to_str (tp->ptid).c_str (), |
| 1721 | paddress (gdbarch, original_pc), |
| 1722 | paddress (gdbarch, displaced_pc)); |
| 1723 | |
| 1724 | return DISPLACED_STEP_PREPARE_STATUS_OK; |
| 1725 | } |
| 1726 | |
| 1727 | /* Wrapper for displaced_step_prepare_throw that disabled further |
| 1728 | attempts at displaced stepping if we get a memory error. */ |
| 1729 | |
| 1730 | static displaced_step_prepare_status |
| 1731 | displaced_step_prepare (thread_info *thread) |
| 1732 | { |
| 1733 | displaced_step_prepare_status status |
| 1734 | = DISPLACED_STEP_PREPARE_STATUS_CANT; |
| 1735 | |
| 1736 | try |
| 1737 | { |
| 1738 | status = displaced_step_prepare_throw (thread); |
| 1739 | } |
| 1740 | catch (const gdb_exception_error &ex) |
| 1741 | { |
| 1742 | if (ex.error != MEMORY_ERROR |
| 1743 | && ex.error != NOT_SUPPORTED_ERROR) |
| 1744 | throw; |
| 1745 | |
| 1746 | infrun_debug_printf ("caught exception, disabling displaced stepping: %s", |
| 1747 | ex.what ()); |
| 1748 | |
| 1749 | /* Be verbose if "set displaced-stepping" is "on", silent if |
| 1750 | "auto". */ |
| 1751 | if (can_use_displaced_stepping == AUTO_BOOLEAN_TRUE) |
| 1752 | { |
| 1753 | warning (_("disabling displaced stepping: %s"), |
| 1754 | ex.what ()); |
| 1755 | } |
| 1756 | |
| 1757 | /* Disable further displaced stepping attempts. */ |
| 1758 | thread->inf->displaced_step_state.failed_before = 1; |
| 1759 | } |
| 1760 | |
| 1761 | return status; |
| 1762 | } |
| 1763 | |
| 1764 | /* If we displaced stepped an instruction successfully, adjust registers and |
| 1765 | memory to yield the same effect the instruction would have had if we had |
| 1766 | executed it at its original address, and return |
| 1767 | DISPLACED_STEP_FINISH_STATUS_OK. If the instruction didn't complete, |
| 1768 | relocate the PC and return DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED. |
| 1769 | |
| 1770 | If the thread wasn't displaced stepping, return |
| 1771 | DISPLACED_STEP_FINISH_STATUS_OK as well. */ |
| 1772 | |
| 1773 | static displaced_step_finish_status |
| 1774 | displaced_step_finish (thread_info *event_thread, enum gdb_signal signal) |
| 1775 | { |
| 1776 | displaced_step_thread_state *displaced = &event_thread->displaced_step_state; |
| 1777 | |
| 1778 | /* Was this thread performing a displaced step? */ |
| 1779 | if (!displaced->in_progress ()) |
| 1780 | return DISPLACED_STEP_FINISH_STATUS_OK; |
| 1781 | |
| 1782 | gdb_assert (event_thread->inf->displaced_step_state.in_progress_count > 0); |
| 1783 | event_thread->inf->displaced_step_state.in_progress_count--; |
| 1784 | |
| 1785 | /* Fixup may need to read memory/registers. Switch to the thread |
| 1786 | that we're fixing up. Also, target_stopped_by_watchpoint checks |
| 1787 | the current thread, and displaced_step_restore performs ptid-dependent |
| 1788 | memory accesses using current_inferior(). */ |
| 1789 | switch_to_thread (event_thread); |
| 1790 | |
| 1791 | displaced_step_reset_cleanup cleanup (displaced); |
| 1792 | |
| 1793 | /* Do the fixup, and release the resources acquired to do the displaced |
| 1794 | step. */ |
| 1795 | return gdbarch_displaced_step_finish (displaced->get_original_gdbarch (), |
| 1796 | event_thread, signal); |
| 1797 | } |
| 1798 | |
| 1799 | /* Data to be passed around while handling an event. This data is |
| 1800 | discarded between events. */ |
| 1801 | struct execution_control_state |
| 1802 | { |
| 1803 | process_stratum_target *target; |
| 1804 | ptid_t ptid; |
| 1805 | /* The thread that got the event, if this was a thread event; NULL |
| 1806 | otherwise. */ |
| 1807 | struct thread_info *event_thread; |
| 1808 | |
| 1809 | struct target_waitstatus ws; |
| 1810 | int stop_func_filled_in; |
| 1811 | CORE_ADDR stop_func_start; |
| 1812 | CORE_ADDR stop_func_end; |
| 1813 | const char *stop_func_name; |
| 1814 | int wait_some_more; |
| 1815 | |
| 1816 | /* True if the event thread hit the single-step breakpoint of |
| 1817 | another thread. Thus the event doesn't cause a stop, the thread |
| 1818 | needs to be single-stepped past the single-step breakpoint before |
| 1819 | we can switch back to the original stepping thread. */ |
| 1820 | int hit_singlestep_breakpoint; |
| 1821 | }; |
| 1822 | |
| 1823 | /* Clear ECS and set it to point at TP. */ |
| 1824 | |
| 1825 | static void |
| 1826 | reset_ecs (struct execution_control_state *ecs, struct thread_info *tp) |
| 1827 | { |
| 1828 | memset (ecs, 0, sizeof (*ecs)); |
| 1829 | ecs->event_thread = tp; |
| 1830 | ecs->ptid = tp->ptid; |
| 1831 | } |
| 1832 | |
| 1833 | static void keep_going_pass_signal (struct execution_control_state *ecs); |
| 1834 | static void prepare_to_wait (struct execution_control_state *ecs); |
| 1835 | static bool keep_going_stepped_thread (struct thread_info *tp); |
| 1836 | static step_over_what thread_still_needs_step_over (struct thread_info *tp); |
| 1837 | |
| 1838 | /* Are there any pending step-over requests? If so, run all we can |
| 1839 | now and return true. Otherwise, return false. */ |
| 1840 | |
| 1841 | static bool |
| 1842 | start_step_over (void) |
| 1843 | { |
| 1844 | INFRUN_SCOPED_DEBUG_ENTER_EXIT; |
| 1845 | |
| 1846 | thread_info *next; |
| 1847 | |
| 1848 | /* Don't start a new step-over if we already have an in-line |
| 1849 | step-over operation ongoing. */ |
| 1850 | if (step_over_info_valid_p ()) |
| 1851 | return false; |
| 1852 | |
| 1853 | /* Steal the global thread step over chain. As we try to initiate displaced |
| 1854 | steps, threads will be enqueued in the global chain if no buffers are |
| 1855 | available. If we iterated on the global chain directly, we might iterate |
| 1856 | indefinitely. */ |
| 1857 | thread_info *threads_to_step = global_thread_step_over_chain_head; |
| 1858 | global_thread_step_over_chain_head = NULL; |
| 1859 | |
| 1860 | infrun_debug_printf ("stealing global queue of threads to step, length = %d", |
| 1861 | thread_step_over_chain_length (threads_to_step)); |
| 1862 | |
| 1863 | bool started = false; |
| 1864 | |
| 1865 | /* On scope exit (whatever the reason, return or exception), if there are |
| 1866 | threads left in the THREADS_TO_STEP chain, put back these threads in the |
| 1867 | global list. */ |
| 1868 | SCOPE_EXIT |
| 1869 | { |
| 1870 | if (threads_to_step == nullptr) |
| 1871 | infrun_debug_printf ("step-over queue now empty"); |
| 1872 | else |
| 1873 | { |
| 1874 | infrun_debug_printf ("putting back %d threads to step in global queue", |
| 1875 | thread_step_over_chain_length (threads_to_step)); |
| 1876 | |
| 1877 | global_thread_step_over_chain_enqueue_chain (threads_to_step); |
| 1878 | } |
| 1879 | }; |
| 1880 | |
| 1881 | for (thread_info *tp = threads_to_step; tp != NULL; tp = next) |
| 1882 | { |
| 1883 | struct execution_control_state ecss; |
| 1884 | struct execution_control_state *ecs = &ecss; |
| 1885 | step_over_what step_what; |
| 1886 | int must_be_in_line; |
| 1887 | |
| 1888 | gdb_assert (!tp->stop_requested); |
| 1889 | |
| 1890 | next = thread_step_over_chain_next (threads_to_step, tp); |
| 1891 | |
| 1892 | if (tp->inf->displaced_step_state.unavailable) |
| 1893 | { |
| 1894 | /* The arch told us to not even try preparing another displaced step |
| 1895 | for this inferior. Just leave the thread in THREADS_TO_STEP, it |
| 1896 | will get moved to the global chain on scope exit. */ |
| 1897 | continue; |
| 1898 | } |
| 1899 | |
| 1900 | /* Remove thread from the THREADS_TO_STEP chain. If anything goes wrong |
| 1901 | while we try to prepare the displaced step, we don't add it back to |
| 1902 | the global step over chain. This is to avoid a thread staying in the |
| 1903 | step over chain indefinitely if something goes wrong when resuming it |
| 1904 | If the error is intermittent and it still needs a step over, it will |
| 1905 | get enqueued again when we try to resume it normally. */ |
| 1906 | thread_step_over_chain_remove (&threads_to_step, tp); |
| 1907 | |
| 1908 | step_what = thread_still_needs_step_over (tp); |
| 1909 | must_be_in_line = ((step_what & STEP_OVER_WATCHPOINT) |
| 1910 | || ((step_what & STEP_OVER_BREAKPOINT) |
| 1911 | && !use_displaced_stepping (tp))); |
| 1912 | |
| 1913 | /* We currently stop all threads of all processes to step-over |
| 1914 | in-line. If we need to start a new in-line step-over, let |
| 1915 | any pending displaced steps finish first. */ |
| 1916 | if (must_be_in_line && displaced_step_in_progress_any_thread ()) |
| 1917 | { |
| 1918 | global_thread_step_over_chain_enqueue (tp); |
| 1919 | continue; |
| 1920 | } |
| 1921 | |
| 1922 | if (tp->control.trap_expected |
| 1923 | || tp->resumed |
| 1924 | || tp->executing) |
| 1925 | { |
| 1926 | internal_error (__FILE__, __LINE__, |
| 1927 | "[%s] has inconsistent state: " |
| 1928 | "trap_expected=%d, resumed=%d, executing=%d\n", |
| 1929 | target_pid_to_str (tp->ptid).c_str (), |
| 1930 | tp->control.trap_expected, |
| 1931 | tp->resumed, |
| 1932 | tp->executing); |
| 1933 | } |
| 1934 | |
| 1935 | infrun_debug_printf ("resuming [%s] for step-over", |
| 1936 | target_pid_to_str (tp->ptid).c_str ()); |
| 1937 | |
| 1938 | /* keep_going_pass_signal skips the step-over if the breakpoint |
| 1939 | is no longer inserted. In all-stop, we want to keep looking |
| 1940 | for a thread that needs a step-over instead of resuming TP, |
| 1941 | because we wouldn't be able to resume anything else until the |
| 1942 | target stops again. In non-stop, the resume always resumes |
| 1943 | only TP, so it's OK to let the thread resume freely. */ |
| 1944 | if (!target_is_non_stop_p () && !step_what) |
| 1945 | continue; |
| 1946 | |
| 1947 | switch_to_thread (tp); |
| 1948 | reset_ecs (ecs, tp); |
| 1949 | keep_going_pass_signal (ecs); |
| 1950 | |
| 1951 | if (!ecs->wait_some_more) |
| 1952 | error (_("Command aborted.")); |
| 1953 | |
| 1954 | /* If the thread's step over could not be initiated because no buffers |
| 1955 | were available, it was re-added to the global step over chain. */ |
| 1956 | if (tp->resumed) |
| 1957 | { |
| 1958 | infrun_debug_printf ("[%s] was resumed.", |
| 1959 | target_pid_to_str (tp->ptid).c_str ()); |
| 1960 | gdb_assert (!thread_is_in_step_over_chain (tp)); |
| 1961 | } |
| 1962 | else |
| 1963 | { |
| 1964 | infrun_debug_printf ("[%s] was NOT resumed.", |
| 1965 | target_pid_to_str (tp->ptid).c_str ()); |
| 1966 | gdb_assert (thread_is_in_step_over_chain (tp)); |
| 1967 | } |
| 1968 | |
| 1969 | /* If we started a new in-line step-over, we're done. */ |
| 1970 | if (step_over_info_valid_p ()) |
| 1971 | { |
| 1972 | gdb_assert (tp->control.trap_expected); |
| 1973 | started = true; |
| 1974 | break; |
| 1975 | } |
| 1976 | |
| 1977 | if (!target_is_non_stop_p ()) |
| 1978 | { |
| 1979 | /* On all-stop, shouldn't have resumed unless we needed a |
| 1980 | step over. */ |
| 1981 | gdb_assert (tp->control.trap_expected |
| 1982 | || tp->step_after_step_resume_breakpoint); |
| 1983 | |
| 1984 | /* With remote targets (at least), in all-stop, we can't |
| 1985 | issue any further remote commands until the program stops |
| 1986 | again. */ |
| 1987 | started = true; |
| 1988 | break; |
| 1989 | } |
| 1990 | |
| 1991 | /* Either the thread no longer needed a step-over, or a new |
| 1992 | displaced stepping sequence started. Even in the latter |
| 1993 | case, continue looking. Maybe we can also start another |
| 1994 | displaced step on a thread of other process. */ |
| 1995 | } |
| 1996 | |
| 1997 | return started; |
| 1998 | } |
| 1999 | |
| 2000 | /* Update global variables holding ptids to hold NEW_PTID if they were |
| 2001 | holding OLD_PTID. */ |
| 2002 | static void |
| 2003 | infrun_thread_ptid_changed (process_stratum_target *target, |
| 2004 | ptid_t old_ptid, ptid_t new_ptid) |
| 2005 | { |
| 2006 | if (inferior_ptid == old_ptid |
| 2007 | && current_inferior ()->process_target () == target) |
| 2008 | inferior_ptid = new_ptid; |
| 2009 | } |
| 2010 | |
| 2011 | \f |
| 2012 | |
| 2013 | static const char schedlock_off[] = "off"; |
| 2014 | static const char schedlock_on[] = "on"; |
| 2015 | static const char schedlock_step[] = "step"; |
| 2016 | static const char schedlock_replay[] = "replay"; |
| 2017 | static const char *const scheduler_enums[] = { |
| 2018 | schedlock_off, |
| 2019 | schedlock_on, |
| 2020 | schedlock_step, |
| 2021 | schedlock_replay, |
| 2022 | NULL |
| 2023 | }; |
| 2024 | static const char *scheduler_mode = schedlock_replay; |
| 2025 | static void |
| 2026 | show_scheduler_mode (struct ui_file *file, int from_tty, |
| 2027 | struct cmd_list_element *c, const char *value) |
| 2028 | { |
| 2029 | fprintf_filtered (file, |
| 2030 | _("Mode for locking scheduler " |
| 2031 | "during execution is \"%s\".\n"), |
| 2032 | value); |
| 2033 | } |
| 2034 | |
| 2035 | static void |
| 2036 | set_schedlock_func (const char *args, int from_tty, struct cmd_list_element *c) |
| 2037 | { |
| 2038 | if (!target_can_lock_scheduler ()) |
| 2039 | { |
| 2040 | scheduler_mode = schedlock_off; |
| 2041 | error (_("Target '%s' cannot support this command."), |
| 2042 | target_shortname ()); |
| 2043 | } |
| 2044 | } |
| 2045 | |
| 2046 | /* True if execution commands resume all threads of all processes by |
| 2047 | default; otherwise, resume only threads of the current inferior |
| 2048 | process. */ |
| 2049 | bool sched_multi = false; |
| 2050 | |
| 2051 | /* Try to setup for software single stepping over the specified location. |
| 2052 | Return true if target_resume() should use hardware single step. |
| 2053 | |
| 2054 | GDBARCH the current gdbarch. |
| 2055 | PC the location to step over. */ |
| 2056 | |
| 2057 | static bool |
| 2058 | maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 2059 | { |
| 2060 | bool hw_step = true; |
| 2061 | |
| 2062 | if (execution_direction == EXEC_FORWARD |
| 2063 | && gdbarch_software_single_step_p (gdbarch)) |
| 2064 | hw_step = !insert_single_step_breakpoints (gdbarch); |
| 2065 | |
| 2066 | return hw_step; |
| 2067 | } |
| 2068 | |
| 2069 | /* See infrun.h. */ |
| 2070 | |
| 2071 | ptid_t |
| 2072 | user_visible_resume_ptid (int step) |
| 2073 | { |
| 2074 | ptid_t resume_ptid; |
| 2075 | |
| 2076 | if (non_stop) |
| 2077 | { |
| 2078 | /* With non-stop mode on, threads are always handled |
| 2079 | individually. */ |
| 2080 | resume_ptid = inferior_ptid; |
| 2081 | } |
| 2082 | else if ((scheduler_mode == schedlock_on) |
| 2083 | || (scheduler_mode == schedlock_step && step)) |
| 2084 | { |
| 2085 | /* User-settable 'scheduler' mode requires solo thread |
| 2086 | resume. */ |
| 2087 | resume_ptid = inferior_ptid; |
| 2088 | } |
| 2089 | else if ((scheduler_mode == schedlock_replay) |
| 2090 | && target_record_will_replay (minus_one_ptid, execution_direction)) |
| 2091 | { |
| 2092 | /* User-settable 'scheduler' mode requires solo thread resume in replay |
| 2093 | mode. */ |
| 2094 | resume_ptid = inferior_ptid; |
| 2095 | } |
| 2096 | else if (!sched_multi && target_supports_multi_process ()) |
| 2097 | { |
| 2098 | /* Resume all threads of the current process (and none of other |
| 2099 | processes). */ |
| 2100 | resume_ptid = ptid_t (inferior_ptid.pid ()); |
| 2101 | } |
| 2102 | else |
| 2103 | { |
| 2104 | /* Resume all threads of all processes. */ |
| 2105 | resume_ptid = RESUME_ALL; |
| 2106 | } |
| 2107 | |
| 2108 | return resume_ptid; |
| 2109 | } |
| 2110 | |
| 2111 | /* See infrun.h. */ |
| 2112 | |
| 2113 | process_stratum_target * |
| 2114 | user_visible_resume_target (ptid_t resume_ptid) |
| 2115 | { |
| 2116 | return (resume_ptid == minus_one_ptid && sched_multi |
| 2117 | ? NULL |
| 2118 | : current_inferior ()->process_target ()); |
| 2119 | } |
| 2120 | |
| 2121 | /* Return a ptid representing the set of threads that we will resume, |
| 2122 | in the perspective of the target, assuming run control handling |
| 2123 | does not require leaving some threads stopped (e.g., stepping past |
| 2124 | breakpoint). USER_STEP indicates whether we're about to start the |
| 2125 | target for a stepping command. */ |
| 2126 | |
| 2127 | static ptid_t |
| 2128 | internal_resume_ptid (int user_step) |
| 2129 | { |
| 2130 | /* In non-stop, we always control threads individually. Note that |
| 2131 | the target may always work in non-stop mode even with "set |
| 2132 | non-stop off", in which case user_visible_resume_ptid could |
| 2133 | return a wildcard ptid. */ |
| 2134 | if (target_is_non_stop_p ()) |
| 2135 | return inferior_ptid; |
| 2136 | else |
| 2137 | return user_visible_resume_ptid (user_step); |
| 2138 | } |
| 2139 | |
| 2140 | /* Wrapper for target_resume, that handles infrun-specific |
| 2141 | bookkeeping. */ |
| 2142 | |
| 2143 | static void |
| 2144 | do_target_resume (ptid_t resume_ptid, bool step, enum gdb_signal sig) |
| 2145 | { |
| 2146 | struct thread_info *tp = inferior_thread (); |
| 2147 | |
| 2148 | gdb_assert (!tp->stop_requested); |
| 2149 | |
| 2150 | /* Install inferior's terminal modes. */ |
| 2151 | target_terminal::inferior (); |
| 2152 | |
| 2153 | /* Avoid confusing the next resume, if the next stop/resume |
| 2154 | happens to apply to another thread. */ |
| 2155 | tp->suspend.stop_signal = GDB_SIGNAL_0; |
| 2156 | |
| 2157 | /* Advise target which signals may be handled silently. |
| 2158 | |
| 2159 | If we have removed breakpoints because we are stepping over one |
| 2160 | in-line (in any thread), we need to receive all signals to avoid |
| 2161 | accidentally skipping a breakpoint during execution of a signal |
| 2162 | handler. |
| 2163 | |
| 2164 | Likewise if we're displaced stepping, otherwise a trap for a |
| 2165 | breakpoint in a signal handler might be confused with the |
| 2166 | displaced step finishing. We don't make the displaced_step_finish |
| 2167 | step distinguish the cases instead, because: |
| 2168 | |
| 2169 | - a backtrace while stopped in the signal handler would show the |
| 2170 | scratch pad as frame older than the signal handler, instead of |
| 2171 | the real mainline code. |
| 2172 | |
| 2173 | - when the thread is later resumed, the signal handler would |
| 2174 | return to the scratch pad area, which would no longer be |
| 2175 | valid. */ |
| 2176 | if (step_over_info_valid_p () |
| 2177 | || displaced_step_in_progress (tp->inf)) |
| 2178 | target_pass_signals ({}); |
| 2179 | else |
| 2180 | target_pass_signals (signal_pass); |
| 2181 | |
| 2182 | target_resume (resume_ptid, step, sig); |
| 2183 | |
| 2184 | if (target_can_async_p ()) |
| 2185 | target_async (1); |
| 2186 | } |
| 2187 | |
| 2188 | /* Resume the inferior. SIG is the signal to give the inferior |
| 2189 | (GDB_SIGNAL_0 for none). Note: don't call this directly; instead |
| 2190 | call 'resume', which handles exceptions. */ |
| 2191 | |
| 2192 | static void |
| 2193 | resume_1 (enum gdb_signal sig) |
| 2194 | { |
| 2195 | struct regcache *regcache = get_current_regcache (); |
| 2196 | struct gdbarch *gdbarch = regcache->arch (); |
| 2197 | struct thread_info *tp = inferior_thread (); |
| 2198 | const address_space *aspace = regcache->aspace (); |
| 2199 | ptid_t resume_ptid; |
| 2200 | /* This represents the user's step vs continue request. When |
| 2201 | deciding whether "set scheduler-locking step" applies, it's the |
| 2202 | user's intention that counts. */ |
| 2203 | const int user_step = tp->control.stepping_command; |
| 2204 | /* This represents what we'll actually request the target to do. |
| 2205 | This can decay from a step to a continue, if e.g., we need to |
| 2206 | implement single-stepping with breakpoints (software |
| 2207 | single-step). */ |
| 2208 | bool step; |
| 2209 | |
| 2210 | gdb_assert (!tp->stop_requested); |
| 2211 | gdb_assert (!thread_is_in_step_over_chain (tp)); |
| 2212 | |
| 2213 | if (tp->suspend.waitstatus_pending_p) |
| 2214 | { |
| 2215 | infrun_debug_printf |
| 2216 | ("thread %s has pending wait " |
| 2217 | "status %s (currently_stepping=%d).", |
| 2218 | target_pid_to_str (tp->ptid).c_str (), |
| 2219 | target_waitstatus_to_string (&tp->suspend.waitstatus).c_str (), |
| 2220 | currently_stepping (tp)); |
| 2221 | |
| 2222 | tp->inf->process_target ()->threads_executing = true; |
| 2223 | tp->resumed = true; |
| 2224 | |
| 2225 | /* FIXME: What should we do if we are supposed to resume this |
| 2226 | thread with a signal? Maybe we should maintain a queue of |
| 2227 | pending signals to deliver. */ |
| 2228 | if (sig != GDB_SIGNAL_0) |
| 2229 | { |
| 2230 | warning (_("Couldn't deliver signal %s to %s."), |
| 2231 | gdb_signal_to_name (sig), |
| 2232 | target_pid_to_str (tp->ptid).c_str ()); |
| 2233 | } |
| 2234 | |
| 2235 | tp->suspend.stop_signal = GDB_SIGNAL_0; |
| 2236 | |
| 2237 | if (target_can_async_p ()) |
| 2238 | { |
| 2239 | target_async (1); |
| 2240 | /* Tell the event loop we have an event to process. */ |
| 2241 | mark_async_event_handler (infrun_async_inferior_event_token); |
| 2242 | } |
| 2243 | return; |
| 2244 | } |
| 2245 | |
| 2246 | tp->stepped_breakpoint = 0; |
| 2247 | |
| 2248 | /* Depends on stepped_breakpoint. */ |
| 2249 | step = currently_stepping (tp); |
| 2250 | |
| 2251 | if (current_inferior ()->waiting_for_vfork_done) |
| 2252 | { |
| 2253 | /* Don't try to single-step a vfork parent that is waiting for |
| 2254 | the child to get out of the shared memory region (by exec'ing |
| 2255 | or exiting). This is particularly important on software |
| 2256 | single-step archs, as the child process would trip on the |
| 2257 | software single step breakpoint inserted for the parent |
| 2258 | process. Since the parent will not actually execute any |
| 2259 | instruction until the child is out of the shared region (such |
| 2260 | are vfork's semantics), it is safe to simply continue it. |
| 2261 | Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for |
| 2262 | the parent, and tell it to `keep_going', which automatically |
| 2263 | re-sets it stepping. */ |
| 2264 | infrun_debug_printf ("resume : clear step"); |
| 2265 | step = false; |
| 2266 | } |
| 2267 | |
| 2268 | CORE_ADDR pc = regcache_read_pc (regcache); |
| 2269 | |
| 2270 | infrun_debug_printf ("step=%d, signal=%s, trap_expected=%d, " |
| 2271 | "current thread [%s] at %s", |
| 2272 | step, gdb_signal_to_symbol_string (sig), |
| 2273 | tp->control.trap_expected, |
| 2274 | target_pid_to_str (inferior_ptid).c_str (), |
| 2275 | paddress (gdbarch, pc)); |
| 2276 | |
| 2277 | /* Normally, by the time we reach `resume', the breakpoints are either |
| 2278 | removed or inserted, as appropriate. The exception is if we're sitting |
| 2279 | at a permanent breakpoint; we need to step over it, but permanent |
| 2280 | breakpoints can't be removed. So we have to test for it here. */ |
| 2281 | if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here) |
| 2282 | { |
| 2283 | if (sig != GDB_SIGNAL_0) |
| 2284 | { |
| 2285 | /* We have a signal to pass to the inferior. The resume |
| 2286 | may, or may not take us to the signal handler. If this |
| 2287 | is a step, we'll need to stop in the signal handler, if |
| 2288 | there's one, (if the target supports stepping into |
| 2289 | handlers), or in the next mainline instruction, if |
| 2290 | there's no handler. If this is a continue, we need to be |
| 2291 | sure to run the handler with all breakpoints inserted. |
| 2292 | In all cases, set a breakpoint at the current address |
| 2293 | (where the handler returns to), and once that breakpoint |
| 2294 | is hit, resume skipping the permanent breakpoint. If |
| 2295 | that breakpoint isn't hit, then we've stepped into the |
| 2296 | signal handler (or hit some other event). We'll delete |
| 2297 | the step-resume breakpoint then. */ |
| 2298 | |
| 2299 | infrun_debug_printf ("resume: skipping permanent breakpoint, " |
| 2300 | "deliver signal first"); |
| 2301 | |
| 2302 | clear_step_over_info (); |
| 2303 | tp->control.trap_expected = 0; |
| 2304 | |
| 2305 | if (tp->control.step_resume_breakpoint == NULL) |
| 2306 | { |
| 2307 | /* Set a "high-priority" step-resume, as we don't want |
| 2308 | user breakpoints at PC to trigger (again) when this |
| 2309 | hits. */ |
| 2310 | insert_hp_step_resume_breakpoint_at_frame (get_current_frame ()); |
| 2311 | gdb_assert (tp->control.step_resume_breakpoint->loc->permanent); |
| 2312 | |
| 2313 | tp->step_after_step_resume_breakpoint = step; |
| 2314 | } |
| 2315 | |
| 2316 | insert_breakpoints (); |
| 2317 | } |
| 2318 | else |
| 2319 | { |
| 2320 | /* There's no signal to pass, we can go ahead and skip the |
| 2321 | permanent breakpoint manually. */ |
| 2322 | infrun_debug_printf ("skipping permanent breakpoint"); |
| 2323 | gdbarch_skip_permanent_breakpoint (gdbarch, regcache); |
| 2324 | /* Update pc to reflect the new address from which we will |
| 2325 | execute instructions. */ |
| 2326 | pc = regcache_read_pc (regcache); |
| 2327 | |
| 2328 | if (step) |
| 2329 | { |
| 2330 | /* We've already advanced the PC, so the stepping part |
| 2331 | is done. Now we need to arrange for a trap to be |
| 2332 | reported to handle_inferior_event. Set a breakpoint |
| 2333 | at the current PC, and run to it. Don't update |
| 2334 | prev_pc, because if we end in |
| 2335 | switch_back_to_stepped_thread, we want the "expected |
| 2336 | thread advanced also" branch to be taken. IOW, we |
| 2337 | don't want this thread to step further from PC |
| 2338 | (overstep). */ |
| 2339 | gdb_assert (!step_over_info_valid_p ()); |
| 2340 | insert_single_step_breakpoint (gdbarch, aspace, pc); |
| 2341 | insert_breakpoints (); |
| 2342 | |
| 2343 | resume_ptid = internal_resume_ptid (user_step); |
| 2344 | do_target_resume (resume_ptid, false, GDB_SIGNAL_0); |
| 2345 | tp->resumed = true; |
| 2346 | return; |
| 2347 | } |
| 2348 | } |
| 2349 | } |
| 2350 | |
| 2351 | /* If we have a breakpoint to step over, make sure to do a single |
| 2352 | step only. Same if we have software watchpoints. */ |
| 2353 | if (tp->control.trap_expected || bpstat_should_step ()) |
| 2354 | tp->control.may_range_step = 0; |
| 2355 | |
| 2356 | /* If displaced stepping is enabled, step over breakpoints by executing a |
| 2357 | copy of the instruction at a different address. |
| 2358 | |
| 2359 | We can't use displaced stepping when we have a signal to deliver; |
| 2360 | the comments for displaced_step_prepare explain why. The |
| 2361 | comments in the handle_inferior event for dealing with 'random |
| 2362 | signals' explain what we do instead. |
| 2363 | |
| 2364 | We can't use displaced stepping when we are waiting for vfork_done |
| 2365 | event, displaced stepping breaks the vfork child similarly as single |
| 2366 | step software breakpoint. */ |
| 2367 | if (tp->control.trap_expected |
| 2368 | && use_displaced_stepping (tp) |
| 2369 | && !step_over_info_valid_p () |
| 2370 | && sig == GDB_SIGNAL_0 |
| 2371 | && !current_inferior ()->waiting_for_vfork_done) |
| 2372 | { |
| 2373 | displaced_step_prepare_status prepare_status |
| 2374 | = displaced_step_prepare (tp); |
| 2375 | |
| 2376 | if (prepare_status == DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE) |
| 2377 | { |
| 2378 | infrun_debug_printf ("Got placed in step-over queue"); |
| 2379 | |
| 2380 | tp->control.trap_expected = 0; |
| 2381 | return; |
| 2382 | } |
| 2383 | else if (prepare_status == DISPLACED_STEP_PREPARE_STATUS_CANT) |
| 2384 | { |
| 2385 | /* Fallback to stepping over the breakpoint in-line. */ |
| 2386 | |
| 2387 | if (target_is_non_stop_p ()) |
| 2388 | stop_all_threads (); |
| 2389 | |
| 2390 | set_step_over_info (regcache->aspace (), |
| 2391 | regcache_read_pc (regcache), 0, tp->global_num); |
| 2392 | |
| 2393 | step = maybe_software_singlestep (gdbarch, pc); |
| 2394 | |
| 2395 | insert_breakpoints (); |
| 2396 | } |
| 2397 | else if (prepare_status == DISPLACED_STEP_PREPARE_STATUS_OK) |
| 2398 | { |
| 2399 | /* Update pc to reflect the new address from which we will |
| 2400 | execute instructions due to displaced stepping. */ |
| 2401 | pc = regcache_read_pc (get_thread_regcache (tp)); |
| 2402 | |
| 2403 | step = gdbarch_displaced_step_hw_singlestep (gdbarch); |
| 2404 | } |
| 2405 | else |
| 2406 | gdb_assert_not_reached (_("Invalid displaced_step_prepare_status " |
| 2407 | "value.")); |
| 2408 | } |
| 2409 | |
| 2410 | /* Do we need to do it the hard way, w/temp breakpoints? */ |
| 2411 | else if (step) |
| 2412 | step = maybe_software_singlestep (gdbarch, pc); |
| 2413 | |
| 2414 | /* Currently, our software single-step implementation leads to different |
| 2415 | results than hardware single-stepping in one situation: when stepping |
| 2416 | into delivering a signal which has an associated signal handler, |
| 2417 | hardware single-step will stop at the first instruction of the handler, |
| 2418 | while software single-step will simply skip execution of the handler. |
| 2419 | |
| 2420 | For now, this difference in behavior is accepted since there is no |
| 2421 | easy way to actually implement single-stepping into a signal handler |
| 2422 | without kernel support. |
| 2423 | |
| 2424 | However, there is one scenario where this difference leads to follow-on |
| 2425 | problems: if we're stepping off a breakpoint by removing all breakpoints |
| 2426 | and then single-stepping. In this case, the software single-step |
| 2427 | behavior means that even if there is a *breakpoint* in the signal |
| 2428 | handler, GDB still would not stop. |
| 2429 | |
| 2430 | Fortunately, we can at least fix this particular issue. We detect |
| 2431 | here the case where we are about to deliver a signal while software |
| 2432 | single-stepping with breakpoints removed. In this situation, we |
| 2433 | revert the decisions to remove all breakpoints and insert single- |
| 2434 | step breakpoints, and instead we install a step-resume breakpoint |
| 2435 | at the current address, deliver the signal without stepping, and |
| 2436 | once we arrive back at the step-resume breakpoint, actually step |
| 2437 | over the breakpoint we originally wanted to step over. */ |
| 2438 | if (thread_has_single_step_breakpoints_set (tp) |
| 2439 | && sig != GDB_SIGNAL_0 |
| 2440 | && step_over_info_valid_p ()) |
| 2441 | { |
| 2442 | /* If we have nested signals or a pending signal is delivered |
| 2443 | immediately after a handler returns, might already have |
| 2444 | a step-resume breakpoint set on the earlier handler. We cannot |
| 2445 | set another step-resume breakpoint; just continue on until the |
| 2446 | original breakpoint is hit. */ |
| 2447 | if (tp->control.step_resume_breakpoint == NULL) |
| 2448 | { |
| 2449 | insert_hp_step_resume_breakpoint_at_frame (get_current_frame ()); |
| 2450 | tp->step_after_step_resume_breakpoint = 1; |
| 2451 | } |
| 2452 | |
| 2453 | delete_single_step_breakpoints (tp); |
| 2454 | |
| 2455 | clear_step_over_info (); |
| 2456 | tp->control.trap_expected = 0; |
| 2457 | |
| 2458 | insert_breakpoints (); |
| 2459 | } |
| 2460 | |
| 2461 | /* If STEP is set, it's a request to use hardware stepping |
| 2462 | facilities. But in that case, we should never |
| 2463 | use singlestep breakpoint. */ |
| 2464 | gdb_assert (!(thread_has_single_step_breakpoints_set (tp) && step)); |
| 2465 | |
| 2466 | /* Decide the set of threads to ask the target to resume. */ |
| 2467 | if (tp->control.trap_expected) |
| 2468 | { |
| 2469 | /* We're allowing a thread to run past a breakpoint it has |
| 2470 | hit, either by single-stepping the thread with the breakpoint |
| 2471 | removed, or by displaced stepping, with the breakpoint inserted. |
| 2472 | In the former case, we need to single-step only this thread, |
| 2473 | and keep others stopped, as they can miss this breakpoint if |
| 2474 | allowed to run. That's not really a problem for displaced |
| 2475 | stepping, but, we still keep other threads stopped, in case |
| 2476 | another thread is also stopped for a breakpoint waiting for |
| 2477 | its turn in the displaced stepping queue. */ |
| 2478 | resume_ptid = inferior_ptid; |
| 2479 | } |
| 2480 | else |
| 2481 | resume_ptid = internal_resume_ptid (user_step); |
| 2482 | |
| 2483 | if (execution_direction != EXEC_REVERSE |
| 2484 | && step && breakpoint_inserted_here_p (aspace, pc)) |
| 2485 | { |
| 2486 | /* There are two cases where we currently need to step a |
| 2487 | breakpoint instruction when we have a signal to deliver: |
| 2488 | |
| 2489 | - See handle_signal_stop where we handle random signals that |
| 2490 | could take out us out of the stepping range. Normally, in |
| 2491 | that case we end up continuing (instead of stepping) over the |
| 2492 | signal handler with a breakpoint at PC, but there are cases |
| 2493 | where we should _always_ single-step, even if we have a |
| 2494 | step-resume breakpoint, like when a software watchpoint is |
| 2495 | set. Assuming single-stepping and delivering a signal at the |
| 2496 | same time would takes us to the signal handler, then we could |
| 2497 | have removed the breakpoint at PC to step over it. However, |
| 2498 | some hardware step targets (like e.g., Mac OS) can't step |
| 2499 | into signal handlers, and for those, we need to leave the |
| 2500 | breakpoint at PC inserted, as otherwise if the handler |
| 2501 | recurses and executes PC again, it'll miss the breakpoint. |
| 2502 | So we leave the breakpoint inserted anyway, but we need to |
| 2503 | record that we tried to step a breakpoint instruction, so |
| 2504 | that adjust_pc_after_break doesn't end up confused. |
| 2505 | |
| 2506 | - In non-stop if we insert a breakpoint (e.g., a step-resume) |
| 2507 | in one thread after another thread that was stepping had been |
| 2508 | momentarily paused for a step-over. When we re-resume the |
| 2509 | stepping thread, it may be resumed from that address with a |
| 2510 | breakpoint that hasn't trapped yet. Seen with |
| 2511 | gdb.threads/non-stop-fair-events.exp, on targets that don't |
| 2512 | do displaced stepping. */ |
| 2513 | |
| 2514 | infrun_debug_printf ("resume: [%s] stepped breakpoint", |
| 2515 | target_pid_to_str (tp->ptid).c_str ()); |
| 2516 | |
| 2517 | tp->stepped_breakpoint = 1; |
| 2518 | |
| 2519 | /* Most targets can step a breakpoint instruction, thus |
| 2520 | executing it normally. But if this one cannot, just |
| 2521 | continue and we will hit it anyway. */ |
| 2522 | if (gdbarch_cannot_step_breakpoint (gdbarch)) |
| 2523 | step = false; |
| 2524 | } |
| 2525 | |
| 2526 | if (debug_displaced |
| 2527 | && tp->control.trap_expected |
| 2528 | && use_displaced_stepping (tp) |
| 2529 | && !step_over_info_valid_p ()) |
| 2530 | { |
| 2531 | struct regcache *resume_regcache = get_thread_regcache (tp); |
| 2532 | struct gdbarch *resume_gdbarch = resume_regcache->arch (); |
| 2533 | CORE_ADDR actual_pc = regcache_read_pc (resume_regcache); |
| 2534 | gdb_byte buf[4]; |
| 2535 | |
| 2536 | read_memory (actual_pc, buf, sizeof (buf)); |
| 2537 | displaced_debug_printf ("run %s: %s", |
| 2538 | paddress (resume_gdbarch, actual_pc), |
| 2539 | displaced_step_dump_bytes |
| 2540 | (buf, sizeof (buf)).c_str ()); |
| 2541 | } |
| 2542 | |
| 2543 | if (tp->control.may_range_step) |
| 2544 | { |
| 2545 | /* If we're resuming a thread with the PC out of the step |
| 2546 | range, then we're doing some nested/finer run control |
| 2547 | operation, like stepping the thread out of the dynamic |
| 2548 | linker or the displaced stepping scratch pad. We |
| 2549 | shouldn't have allowed a range step then. */ |
| 2550 | gdb_assert (pc_in_thread_step_range (pc, tp)); |
| 2551 | } |
| 2552 | |
| 2553 | do_target_resume (resume_ptid, step, sig); |
| 2554 | tp->resumed = true; |
| 2555 | } |
| 2556 | |
| 2557 | /* Resume the inferior. SIG is the signal to give the inferior |
| 2558 | (GDB_SIGNAL_0 for none). This is a wrapper around 'resume_1' that |
| 2559 | rolls back state on error. */ |
| 2560 | |
| 2561 | static void |
| 2562 | resume (gdb_signal sig) |
| 2563 | { |
| 2564 | try |
| 2565 | { |
| 2566 | resume_1 (sig); |
| 2567 | } |
| 2568 | catch (const gdb_exception &ex) |
| 2569 | { |
| 2570 | /* If resuming is being aborted for any reason, delete any |
| 2571 | single-step breakpoint resume_1 may have created, to avoid |
| 2572 | confusing the following resumption, and to avoid leaving |
| 2573 | single-step breakpoints perturbing other threads, in case |
| 2574 | we're running in non-stop mode. */ |
| 2575 | if (inferior_ptid != null_ptid) |
| 2576 | delete_single_step_breakpoints (inferior_thread ()); |
| 2577 | throw; |
| 2578 | } |
| 2579 | } |
| 2580 | |
| 2581 | \f |
| 2582 | /* Proceeding. */ |
| 2583 | |
| 2584 | /* See infrun.h. */ |
| 2585 | |
| 2586 | /* Counter that tracks number of user visible stops. This can be used |
| 2587 | to tell whether a command has proceeded the inferior past the |
| 2588 | current location. This allows e.g., inferior function calls in |
| 2589 | breakpoint commands to not interrupt the command list. When the |
| 2590 | call finishes successfully, the inferior is standing at the same |
| 2591 | breakpoint as if nothing happened (and so we don't call |
| 2592 | normal_stop). */ |
| 2593 | static ULONGEST current_stop_id; |
| 2594 | |
| 2595 | /* See infrun.h. */ |
| 2596 | |
| 2597 | ULONGEST |
| 2598 | get_stop_id (void) |
| 2599 | { |
| 2600 | return current_stop_id; |
| 2601 | } |
| 2602 | |
| 2603 | /* Called when we report a user visible stop. */ |
| 2604 | |
| 2605 | static void |
| 2606 | new_stop_id (void) |
| 2607 | { |
| 2608 | current_stop_id++; |
| 2609 | } |
| 2610 | |
| 2611 | /* Clear out all variables saying what to do when inferior is continued. |
| 2612 | First do this, then set the ones you want, then call `proceed'. */ |
| 2613 | |
| 2614 | static void |
| 2615 | clear_proceed_status_thread (struct thread_info *tp) |
| 2616 | { |
| 2617 | infrun_debug_printf ("%s", target_pid_to_str (tp->ptid).c_str ()); |
| 2618 | |
| 2619 | /* If we're starting a new sequence, then the previous finished |
| 2620 | single-step is no longer relevant. */ |
| 2621 | if (tp->suspend.waitstatus_pending_p) |
| 2622 | { |
| 2623 | if (tp->suspend.stop_reason == TARGET_STOPPED_BY_SINGLE_STEP) |
| 2624 | { |
| 2625 | infrun_debug_printf ("pending event of %s was a finished step. " |
| 2626 | "Discarding.", |
| 2627 | target_pid_to_str (tp->ptid).c_str ()); |
| 2628 | |
| 2629 | tp->suspend.waitstatus_pending_p = 0; |
| 2630 | tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON; |
| 2631 | } |
| 2632 | else |
| 2633 | { |
| 2634 | infrun_debug_printf |
| 2635 | ("thread %s has pending wait status %s (currently_stepping=%d).", |
| 2636 | target_pid_to_str (tp->ptid).c_str (), |
| 2637 | target_waitstatus_to_string (&tp->suspend.waitstatus).c_str (), |
| 2638 | currently_stepping (tp)); |
| 2639 | } |
| 2640 | } |
| 2641 | |
| 2642 | /* If this signal should not be seen by program, give it zero. |
| 2643 | Used for debugging signals. */ |
| 2644 | if (!signal_pass_state (tp->suspend.stop_signal)) |
| 2645 | tp->suspend.stop_signal = GDB_SIGNAL_0; |
| 2646 | |
| 2647 | delete tp->thread_fsm; |
| 2648 | tp->thread_fsm = NULL; |
| 2649 | |
| 2650 | tp->control.trap_expected = 0; |
| 2651 | tp->control.step_range_start = 0; |
| 2652 | tp->control.step_range_end = 0; |
| 2653 | tp->control.may_range_step = 0; |
| 2654 | tp->control.step_frame_id = null_frame_id; |
| 2655 | tp->control.step_stack_frame_id = null_frame_id; |
| 2656 | tp->control.step_over_calls = STEP_OVER_UNDEBUGGABLE; |
| 2657 | tp->control.step_start_function = NULL; |
| 2658 | tp->stop_requested = 0; |
| 2659 | |
| 2660 | tp->control.stop_step = 0; |
| 2661 | |
| 2662 | tp->control.proceed_to_finish = 0; |
| 2663 | |
| 2664 | tp->control.stepping_command = 0; |
| 2665 | |
| 2666 | /* Discard any remaining commands or status from previous stop. */ |
| 2667 | bpstat_clear (&tp->control.stop_bpstat); |
| 2668 | } |
| 2669 | |
| 2670 | void |
| 2671 | clear_proceed_status (int step) |
| 2672 | { |
| 2673 | /* With scheduler-locking replay, stop replaying other threads if we're |
| 2674 | not replaying the user-visible resume ptid. |
| 2675 | |
| 2676 | This is a convenience feature to not require the user to explicitly |
| 2677 | stop replaying the other threads. We're assuming that the user's |
| 2678 | intent is to resume tracing the recorded process. */ |
| 2679 | if (!non_stop && scheduler_mode == schedlock_replay |
| 2680 | && target_record_is_replaying (minus_one_ptid) |
| 2681 | && !target_record_will_replay (user_visible_resume_ptid (step), |
| 2682 | execution_direction)) |
| 2683 | target_record_stop_replaying (); |
| 2684 | |
| 2685 | if (!non_stop && inferior_ptid != null_ptid) |
| 2686 | { |
| 2687 | ptid_t resume_ptid = user_visible_resume_ptid (step); |
| 2688 | process_stratum_target *resume_target |
| 2689 | = user_visible_resume_target (resume_ptid); |
| 2690 | |
| 2691 | /* In all-stop mode, delete the per-thread status of all threads |
| 2692 | we're about to resume, implicitly and explicitly. */ |
| 2693 | for (thread_info *tp : all_non_exited_threads (resume_target, resume_ptid)) |
| 2694 | clear_proceed_status_thread (tp); |
| 2695 | } |
| 2696 | |
| 2697 | if (inferior_ptid != null_ptid) |
| 2698 | { |
| 2699 | struct inferior *inferior; |
| 2700 | |
| 2701 | if (non_stop) |
| 2702 | { |
| 2703 | /* If in non-stop mode, only delete the per-thread status of |
| 2704 | the current thread. */ |
| 2705 | clear_proceed_status_thread (inferior_thread ()); |
| 2706 | } |
| 2707 | |
| 2708 | inferior = current_inferior (); |
| 2709 | inferior->control.stop_soon = NO_STOP_QUIETLY; |
| 2710 | } |
| 2711 | |
| 2712 | gdb::observers::about_to_proceed.notify (); |
| 2713 | } |
| 2714 | |
| 2715 | /* Returns true if TP is still stopped at a breakpoint that needs |
| 2716 | stepping-over in order to make progress. If the breakpoint is gone |
| 2717 | meanwhile, we can skip the whole step-over dance. */ |
| 2718 | |
| 2719 | static bool |
| 2720 | thread_still_needs_step_over_bp (struct thread_info *tp) |
| 2721 | { |
| 2722 | if (tp->stepping_over_breakpoint) |
| 2723 | { |
| 2724 | struct regcache *regcache = get_thread_regcache (tp); |
| 2725 | |
| 2726 | if (breakpoint_here_p (regcache->aspace (), |
| 2727 | regcache_read_pc (regcache)) |
| 2728 | == ordinary_breakpoint_here) |
| 2729 | return true; |
| 2730 | |
| 2731 | tp->stepping_over_breakpoint = 0; |
| 2732 | } |
| 2733 | |
| 2734 | return false; |
| 2735 | } |
| 2736 | |
| 2737 | /* Check whether thread TP still needs to start a step-over in order |
| 2738 | to make progress when resumed. Returns an bitwise or of enum |
| 2739 | step_over_what bits, indicating what needs to be stepped over. */ |
| 2740 | |
| 2741 | static step_over_what |
| 2742 | thread_still_needs_step_over (struct thread_info *tp) |
| 2743 | { |
| 2744 | step_over_what what = 0; |
| 2745 | |
| 2746 | if (thread_still_needs_step_over_bp (tp)) |
| 2747 | what |= STEP_OVER_BREAKPOINT; |
| 2748 | |
| 2749 | if (tp->stepping_over_watchpoint |
| 2750 | && !target_have_steppable_watchpoint ()) |
| 2751 | what |= STEP_OVER_WATCHPOINT; |
| 2752 | |
| 2753 | return what; |
| 2754 | } |
| 2755 | |
| 2756 | /* Returns true if scheduler locking applies. STEP indicates whether |
| 2757 | we're about to do a step/next-like command to a thread. */ |
| 2758 | |
| 2759 | static bool |
| 2760 | schedlock_applies (struct thread_info *tp) |
| 2761 | { |
| 2762 | return (scheduler_mode == schedlock_on |
| 2763 | || (scheduler_mode == schedlock_step |
| 2764 | && tp->control.stepping_command) |
| 2765 | || (scheduler_mode == schedlock_replay |
| 2766 | && target_record_will_replay (minus_one_ptid, |
| 2767 | execution_direction))); |
| 2768 | } |
| 2769 | |
| 2770 | /* Set process_stratum_target::COMMIT_RESUMED_STATE in all target |
| 2771 | stacks that have threads executing and don't have threads with |
| 2772 | pending events. */ |
| 2773 | |
| 2774 | static void |
| 2775 | maybe_set_commit_resumed_all_targets () |
| 2776 | { |
| 2777 | scoped_restore_current_thread restore_thread; |
| 2778 | |
| 2779 | for (inferior *inf : all_non_exited_inferiors ()) |
| 2780 | { |
| 2781 | process_stratum_target *proc_target = inf->process_target (); |
| 2782 | |
| 2783 | if (proc_target->commit_resumed_state) |
| 2784 | { |
| 2785 | /* We already set this in a previous iteration, via another |
| 2786 | inferior sharing the process_stratum target. */ |
| 2787 | continue; |
| 2788 | } |
| 2789 | |
| 2790 | /* If the target has no resumed threads, it would be useless to |
| 2791 | ask it to commit the resumed threads. */ |
| 2792 | if (!proc_target->threads_executing) |
| 2793 | { |
| 2794 | infrun_debug_printf ("not requesting commit-resumed for target " |
| 2795 | "%s, no resumed threads", |
| 2796 | proc_target->shortname ()); |
| 2797 | continue; |
| 2798 | } |
| 2799 | |
| 2800 | /* As an optimization, if a thread from this target has some |
| 2801 | status to report, handle it before requiring the target to |
| 2802 | commit its resumed threads: handling the status might lead to |
| 2803 | resuming more threads. */ |
| 2804 | bool has_thread_with_pending_status = false; |
| 2805 | for (thread_info *thread : all_non_exited_threads (proc_target)) |
| 2806 | if (thread->resumed && thread->suspend.waitstatus_pending_p) |
| 2807 | { |
| 2808 | has_thread_with_pending_status = true; |
| 2809 | break; |
| 2810 | } |
| 2811 | |
| 2812 | if (has_thread_with_pending_status) |
| 2813 | { |
| 2814 | infrun_debug_printf ("not requesting commit-resumed for target %s, a" |
| 2815 | " thread has a pending waitstatus", |
| 2816 | proc_target->shortname ()); |
| 2817 | continue; |
| 2818 | } |
| 2819 | |
| 2820 | switch_to_inferior_no_thread (inf); |
| 2821 | |
| 2822 | if (target_has_pending_events ()) |
| 2823 | { |
| 2824 | infrun_debug_printf ("not requesting commit-resumed for target %s, " |
| 2825 | "target has pending events", |
| 2826 | proc_target->shortname ()); |
| 2827 | continue; |
| 2828 | } |
| 2829 | |
| 2830 | infrun_debug_printf ("enabling commit-resumed for target %s", |
| 2831 | proc_target->shortname ()); |
| 2832 | |
| 2833 | proc_target->commit_resumed_state = true; |
| 2834 | } |
| 2835 | } |
| 2836 | |
| 2837 | /* See infrun.h. */ |
| 2838 | |
| 2839 | void |
| 2840 | maybe_call_commit_resumed_all_targets () |
| 2841 | { |
| 2842 | scoped_restore_current_thread restore_thread; |
| 2843 | |
| 2844 | for (inferior *inf : all_non_exited_inferiors ()) |
| 2845 | { |
| 2846 | process_stratum_target *proc_target = inf->process_target (); |
| 2847 | |
| 2848 | if (!proc_target->commit_resumed_state) |
| 2849 | continue; |
| 2850 | |
| 2851 | switch_to_inferior_no_thread (inf); |
| 2852 | |
| 2853 | infrun_debug_printf ("calling commit_resumed for target %s", |
| 2854 | proc_target->shortname()); |
| 2855 | |
| 2856 | target_commit_resumed (); |
| 2857 | } |
| 2858 | } |
| 2859 | |
| 2860 | /* To track nesting of scoped_disable_commit_resumed objects, ensuring |
| 2861 | that only the outermost one attempts to re-enable |
| 2862 | commit-resumed. */ |
| 2863 | static bool enable_commit_resumed = true; |
| 2864 | |
| 2865 | /* See infrun.h. */ |
| 2866 | |
| 2867 | scoped_disable_commit_resumed::scoped_disable_commit_resumed |
| 2868 | (const char *reason) |
| 2869 | : m_reason (reason), |
| 2870 | m_prev_enable_commit_resumed (enable_commit_resumed) |
| 2871 | { |
| 2872 | infrun_debug_printf ("reason=%s", m_reason); |
| 2873 | |
| 2874 | enable_commit_resumed = false; |
| 2875 | |
| 2876 | for (inferior *inf : all_non_exited_inferiors ()) |
| 2877 | { |
| 2878 | process_stratum_target *proc_target = inf->process_target (); |
| 2879 | |
| 2880 | if (m_prev_enable_commit_resumed) |
| 2881 | { |
| 2882 | /* This is the outermost instance: force all |
| 2883 | COMMIT_RESUMED_STATE to false. */ |
| 2884 | proc_target->commit_resumed_state = false; |
| 2885 | } |
| 2886 | else |
| 2887 | { |
| 2888 | /* This is not the outermost instance, we expect |
| 2889 | COMMIT_RESUMED_STATE to have been cleared by the |
| 2890 | outermost instance. */ |
| 2891 | gdb_assert (!proc_target->commit_resumed_state); |
| 2892 | } |
| 2893 | } |
| 2894 | } |
| 2895 | |
| 2896 | /* See infrun.h. */ |
| 2897 | |
| 2898 | void |
| 2899 | scoped_disable_commit_resumed::reset () |
| 2900 | { |
| 2901 | if (m_reset) |
| 2902 | return; |
| 2903 | m_reset = true; |
| 2904 | |
| 2905 | infrun_debug_printf ("reason=%s", m_reason); |
| 2906 | |
| 2907 | gdb_assert (!enable_commit_resumed); |
| 2908 | |
| 2909 | enable_commit_resumed = m_prev_enable_commit_resumed; |
| 2910 | |
| 2911 | if (m_prev_enable_commit_resumed) |
| 2912 | { |
| 2913 | /* This is the outermost instance, re-enable |
| 2914 | COMMIT_RESUMED_STATE on the targets where it's possible. */ |
| 2915 | maybe_set_commit_resumed_all_targets (); |
| 2916 | } |
| 2917 | else |
| 2918 | { |
| 2919 | /* This is not the outermost instance, we expect |
| 2920 | COMMIT_RESUMED_STATE to still be false. */ |
| 2921 | for (inferior *inf : all_non_exited_inferiors ()) |
| 2922 | { |
| 2923 | process_stratum_target *proc_target = inf->process_target (); |
| 2924 | gdb_assert (!proc_target->commit_resumed_state); |
| 2925 | } |
| 2926 | } |
| 2927 | } |
| 2928 | |
| 2929 | /* See infrun.h. */ |
| 2930 | |
| 2931 | scoped_disable_commit_resumed::~scoped_disable_commit_resumed () |
| 2932 | { |
| 2933 | reset (); |
| 2934 | } |
| 2935 | |
| 2936 | /* See infrun.h. */ |
| 2937 | |
| 2938 | void |
| 2939 | scoped_disable_commit_resumed::reset_and_commit () |
| 2940 | { |
| 2941 | reset (); |
| 2942 | maybe_call_commit_resumed_all_targets (); |
| 2943 | } |
| 2944 | |
| 2945 | /* See infrun.h. */ |
| 2946 | |
| 2947 | scoped_enable_commit_resumed::scoped_enable_commit_resumed |
| 2948 | (const char *reason) |
| 2949 | : m_reason (reason), |
| 2950 | m_prev_enable_commit_resumed (enable_commit_resumed) |
| 2951 | { |
| 2952 | infrun_debug_printf ("reason=%s", m_reason); |
| 2953 | |
| 2954 | if (!enable_commit_resumed) |
| 2955 | { |
| 2956 | enable_commit_resumed = true; |
| 2957 | |
| 2958 | /* Re-enable COMMIT_RESUMED_STATE on the targets where it's |
| 2959 | possible. */ |
| 2960 | maybe_set_commit_resumed_all_targets (); |
| 2961 | |
| 2962 | maybe_call_commit_resumed_all_targets (); |
| 2963 | } |
| 2964 | } |
| 2965 | |
| 2966 | /* See infrun.h. */ |
| 2967 | |
| 2968 | scoped_enable_commit_resumed::~scoped_enable_commit_resumed () |
| 2969 | { |
| 2970 | infrun_debug_printf ("reason=%s", m_reason); |
| 2971 | |
| 2972 | gdb_assert (enable_commit_resumed); |
| 2973 | |
| 2974 | enable_commit_resumed = m_prev_enable_commit_resumed; |
| 2975 | |
| 2976 | if (!enable_commit_resumed) |
| 2977 | { |
| 2978 | /* Force all COMMIT_RESUMED_STATE back to false. */ |
| 2979 | for (inferior *inf : all_non_exited_inferiors ()) |
| 2980 | { |
| 2981 | process_stratum_target *proc_target = inf->process_target (); |
| 2982 | proc_target->commit_resumed_state = false; |
| 2983 | } |
| 2984 | } |
| 2985 | } |
| 2986 | |
| 2987 | /* Check that all the targets we're about to resume are in non-stop |
| 2988 | mode. Ideally, we'd only care whether all targets support |
| 2989 | target-async, but we're not there yet. E.g., stop_all_threads |
| 2990 | doesn't know how to handle all-stop targets. Also, the remote |
| 2991 | protocol in all-stop mode is synchronous, irrespective of |
| 2992 | target-async, which means that things like a breakpoint re-set |
| 2993 | triggered by one target would try to read memory from all targets |
| 2994 | and fail. */ |
| 2995 | |
| 2996 | static void |
| 2997 | check_multi_target_resumption (process_stratum_target *resume_target) |
| 2998 | { |
| 2999 | if (!non_stop && resume_target == nullptr) |
| 3000 | { |
| 3001 | scoped_restore_current_thread restore_thread; |
| 3002 | |
| 3003 | /* This is used to track whether we're resuming more than one |
| 3004 | target. */ |
| 3005 | process_stratum_target *first_connection = nullptr; |
| 3006 | |
| 3007 | /* The first inferior we see with a target that does not work in |
| 3008 | always-non-stop mode. */ |
| 3009 | inferior *first_not_non_stop = nullptr; |
| 3010 | |
| 3011 | for (inferior *inf : all_non_exited_inferiors ()) |
| 3012 | { |
| 3013 | switch_to_inferior_no_thread (inf); |
| 3014 | |
| 3015 | if (!target_has_execution ()) |
| 3016 | continue; |
| 3017 | |
| 3018 | process_stratum_target *proc_target |
| 3019 | = current_inferior ()->process_target(); |
| 3020 | |
| 3021 | if (!target_is_non_stop_p ()) |
| 3022 | first_not_non_stop = inf; |
| 3023 | |
| 3024 | if (first_connection == nullptr) |
| 3025 | first_connection = proc_target; |
| 3026 | else if (first_connection != proc_target |
| 3027 | && first_not_non_stop != nullptr) |
| 3028 | { |
| 3029 | switch_to_inferior_no_thread (first_not_non_stop); |
| 3030 | |
| 3031 | proc_target = current_inferior ()->process_target(); |
| 3032 | |
| 3033 | error (_("Connection %d (%s) does not support " |
| 3034 | "multi-target resumption."), |
| 3035 | proc_target->connection_number, |
| 3036 | make_target_connection_string (proc_target).c_str ()); |
| 3037 | } |
| 3038 | } |
| 3039 | } |
| 3040 | } |
| 3041 | |
| 3042 | /* Basic routine for continuing the program in various fashions. |
| 3043 | |
| 3044 | ADDR is the address to resume at, or -1 for resume where stopped. |
| 3045 | SIGGNAL is the signal to give it, or GDB_SIGNAL_0 for none, |
| 3046 | or GDB_SIGNAL_DEFAULT for act according to how it stopped. |
| 3047 | |
| 3048 | You should call clear_proceed_status before calling proceed. */ |
| 3049 | |
| 3050 | void |
| 3051 | proceed (CORE_ADDR addr, enum gdb_signal siggnal) |
| 3052 | { |
| 3053 | INFRUN_SCOPED_DEBUG_ENTER_EXIT; |
| 3054 | |
| 3055 | struct regcache *regcache; |
| 3056 | struct gdbarch *gdbarch; |
| 3057 | CORE_ADDR pc; |
| 3058 | struct execution_control_state ecss; |
| 3059 | struct execution_control_state *ecs = &ecss; |
| 3060 | bool started; |
| 3061 | |
| 3062 | /* If we're stopped at a fork/vfork, follow the branch set by the |
| 3063 | "set follow-fork-mode" command; otherwise, we'll just proceed |
| 3064 | resuming the current thread. */ |
| 3065 | if (!follow_fork ()) |
| 3066 | { |
| 3067 | /* The target for some reason decided not to resume. */ |
| 3068 | normal_stop (); |
| 3069 | if (target_can_async_p ()) |
| 3070 | inferior_event_handler (INF_EXEC_COMPLETE); |
| 3071 | return; |
| 3072 | } |
| 3073 | |
| 3074 | /* We'll update this if & when we switch to a new thread. */ |
| 3075 | previous_inferior_ptid = inferior_ptid; |
| 3076 | |
| 3077 | regcache = get_current_regcache (); |
| 3078 | gdbarch = regcache->arch (); |
| 3079 | const address_space *aspace = regcache->aspace (); |
| 3080 | |
| 3081 | pc = regcache_read_pc_protected (regcache); |
| 3082 | |
| 3083 | thread_info *cur_thr = inferior_thread (); |
| 3084 | |
| 3085 | /* Fill in with reasonable starting values. */ |
| 3086 | init_thread_stepping_state (cur_thr); |
| 3087 | |
| 3088 | gdb_assert (!thread_is_in_step_over_chain (cur_thr)); |
| 3089 | |
| 3090 | ptid_t resume_ptid |
| 3091 | = user_visible_resume_ptid (cur_thr->control.stepping_command); |
| 3092 | process_stratum_target *resume_target |
| 3093 | = user_visible_resume_target (resume_ptid); |
| 3094 | |
| 3095 | check_multi_target_resumption (resume_target); |
| 3096 | |
| 3097 | if (addr == (CORE_ADDR) -1) |
| 3098 | { |
| 3099 | if (pc == cur_thr->suspend.stop_pc |
| 3100 | && breakpoint_here_p (aspace, pc) == ordinary_breakpoint_here |
| 3101 | && execution_direction != EXEC_REVERSE) |
| 3102 | /* There is a breakpoint at the address we will resume at, |
| 3103 | step one instruction before inserting breakpoints so that |
| 3104 | we do not stop right away (and report a second hit at this |
| 3105 | breakpoint). |
| 3106 | |
| 3107 | Note, we don't do this in reverse, because we won't |
| 3108 | actually be executing the breakpoint insn anyway. |
| 3109 | We'll be (un-)executing the previous instruction. */ |
| 3110 | cur_thr->stepping_over_breakpoint = 1; |
| 3111 | else if (gdbarch_single_step_through_delay_p (gdbarch) |
| 3112 | && gdbarch_single_step_through_delay (gdbarch, |
| 3113 | get_current_frame ())) |
| 3114 | /* We stepped onto an instruction that needs to be stepped |
| 3115 | again before re-inserting the breakpoint, do so. */ |
| 3116 | cur_thr->stepping_over_breakpoint = 1; |
| 3117 | } |
| 3118 | else |
| 3119 | { |
| 3120 | regcache_write_pc (regcache, addr); |
| 3121 | } |
| 3122 | |
| 3123 | if (siggnal != GDB_SIGNAL_DEFAULT) |
| 3124 | cur_thr->suspend.stop_signal = siggnal; |
| 3125 | |
| 3126 | /* If an exception is thrown from this point on, make sure to |
| 3127 | propagate GDB's knowledge of the executing state to the |
| 3128 | frontend/user running state. */ |
| 3129 | scoped_finish_thread_state finish_state (resume_target, resume_ptid); |
| 3130 | |
| 3131 | /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer |
| 3132 | threads (e.g., we might need to set threads stepping over |
| 3133 | breakpoints first), from the user/frontend's point of view, all |
| 3134 | threads in RESUME_PTID are now running. Unless we're calling an |
| 3135 | inferior function, as in that case we pretend the inferior |
| 3136 | doesn't run at all. */ |
| 3137 | if (!cur_thr->control.in_infcall) |
| 3138 | set_running (resume_target, resume_ptid, true); |
| 3139 | |
| 3140 | infrun_debug_printf ("addr=%s, signal=%s", paddress (gdbarch, addr), |
| 3141 | gdb_signal_to_symbol_string (siggnal)); |
| 3142 | |
| 3143 | annotate_starting (); |
| 3144 | |
| 3145 | /* Make sure that output from GDB appears before output from the |
| 3146 | inferior. */ |
| 3147 | gdb_flush (gdb_stdout); |
| 3148 | |
| 3149 | /* Since we've marked the inferior running, give it the terminal. A |
| 3150 | QUIT/Ctrl-C from here on is forwarded to the target (which can |
| 3151 | still detect attempts to unblock a stuck connection with repeated |
| 3152 | Ctrl-C from within target_pass_ctrlc). */ |
| 3153 | target_terminal::inferior (); |
| 3154 | |
| 3155 | /* In a multi-threaded task we may select another thread and |
| 3156 | then continue or step. |
| 3157 | |
| 3158 | But if a thread that we're resuming had stopped at a breakpoint, |
| 3159 | it will immediately cause another breakpoint stop without any |
| 3160 | execution (i.e. it will report a breakpoint hit incorrectly). So |
| 3161 | we must step over it first. |
| 3162 | |
| 3163 | Look for threads other than the current (TP) that reported a |
| 3164 | breakpoint hit and haven't been resumed yet since. */ |
| 3165 | |
| 3166 | /* If scheduler locking applies, we can avoid iterating over all |
| 3167 | threads. */ |
| 3168 | if (!non_stop && !schedlock_applies (cur_thr)) |
| 3169 | { |
| 3170 | for (thread_info *tp : all_non_exited_threads (resume_target, |
| 3171 | resume_ptid)) |
| 3172 | { |
| 3173 | switch_to_thread_no_regs (tp); |
| 3174 | |
| 3175 | /* Ignore the current thread here. It's handled |
| 3176 | afterwards. */ |
| 3177 | if (tp == cur_thr) |
| 3178 | continue; |
| 3179 | |
| 3180 | if (!thread_still_needs_step_over (tp)) |
| 3181 | continue; |
| 3182 | |
| 3183 | gdb_assert (!thread_is_in_step_over_chain (tp)); |
| 3184 | |
| 3185 | infrun_debug_printf ("need to step-over [%s] first", |
| 3186 | target_pid_to_str (tp->ptid).c_str ()); |
| 3187 | |
| 3188 | global_thread_step_over_chain_enqueue (tp); |
| 3189 | } |
| 3190 | |
| 3191 | switch_to_thread (cur_thr); |
| 3192 | } |
| 3193 | |
| 3194 | /* Enqueue the current thread last, so that we move all other |
| 3195 | threads over their breakpoints first. */ |
| 3196 | if (cur_thr->stepping_over_breakpoint) |
| 3197 | global_thread_step_over_chain_enqueue (cur_thr); |
| 3198 | |
| 3199 | /* If the thread isn't started, we'll still need to set its prev_pc, |
| 3200 | so that switch_back_to_stepped_thread knows the thread hasn't |
| 3201 | advanced. Must do this before resuming any thread, as in |
| 3202 | all-stop/remote, once we resume we can't send any other packet |
| 3203 | until the target stops again. */ |
| 3204 | cur_thr->prev_pc = regcache_read_pc_protected (regcache); |
| 3205 | |
| 3206 | { |
| 3207 | scoped_disable_commit_resumed disable_commit_resumed ("proceeding"); |
| 3208 | |
| 3209 | started = start_step_over (); |
| 3210 | |
| 3211 | if (step_over_info_valid_p ()) |
| 3212 | { |
| 3213 | /* Either this thread started a new in-line step over, or some |
| 3214 | other thread was already doing one. In either case, don't |
| 3215 | resume anything else until the step-over is finished. */ |
| 3216 | } |
| 3217 | else if (started && !target_is_non_stop_p ()) |
| 3218 | { |
| 3219 | /* A new displaced stepping sequence was started. In all-stop, |
| 3220 | we can't talk to the target anymore until it next stops. */ |
| 3221 | } |
| 3222 | else if (!non_stop && target_is_non_stop_p ()) |
| 3223 | { |
| 3224 | INFRUN_SCOPED_DEBUG_START_END |
| 3225 | ("resuming threads, all-stop-on-top-of-non-stop"); |
| 3226 | |
| 3227 | /* In all-stop, but the target is always in non-stop mode. |
| 3228 | Start all other threads that are implicitly resumed too. */ |
| 3229 | for (thread_info *tp : all_non_exited_threads (resume_target, |
| 3230 | resume_ptid)) |
| 3231 | { |
| 3232 | switch_to_thread_no_regs (tp); |
| 3233 | |
| 3234 | if (!tp->inf->has_execution ()) |
| 3235 | { |
| 3236 | infrun_debug_printf ("[%s] target has no execution", |
| 3237 | target_pid_to_str (tp->ptid).c_str ()); |
| 3238 | continue; |
| 3239 | } |
| 3240 | |
| 3241 | if (tp->resumed) |
| 3242 | { |
| 3243 | infrun_debug_printf ("[%s] resumed", |
| 3244 | target_pid_to_str (tp->ptid).c_str ()); |
| 3245 | gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p); |
| 3246 | continue; |
| 3247 | } |
| 3248 | |
| 3249 | if (thread_is_in_step_over_chain (tp)) |
| 3250 | { |
| 3251 | infrun_debug_printf ("[%s] needs step-over", |
| 3252 | target_pid_to_str (tp->ptid).c_str ()); |
| 3253 | continue; |
| 3254 | } |
| 3255 | |
| 3256 | infrun_debug_printf ("resuming %s", |
| 3257 | target_pid_to_str (tp->ptid).c_str ()); |
| 3258 | |
| 3259 | reset_ecs (ecs, tp); |
| 3260 | switch_to_thread (tp); |
| 3261 | keep_going_pass_signal (ecs); |
| 3262 | if (!ecs->wait_some_more) |
| 3263 | error (_("Command aborted.")); |
| 3264 | } |
| 3265 | } |
| 3266 | else if (!cur_thr->resumed && !thread_is_in_step_over_chain (cur_thr)) |
| 3267 | { |
| 3268 | /* The thread wasn't started, and isn't queued, run it now. */ |
| 3269 | reset_ecs (ecs, cur_thr); |
| 3270 | switch_to_thread (cur_thr); |
| 3271 | keep_going_pass_signal (ecs); |
| 3272 | if (!ecs->wait_some_more) |
| 3273 | error (_("Command aborted.")); |
| 3274 | } |
| 3275 | |
| 3276 | disable_commit_resumed.reset_and_commit (); |
| 3277 | } |
| 3278 | |
| 3279 | finish_state.release (); |
| 3280 | |
| 3281 | /* If we've switched threads above, switch back to the previously |
| 3282 | current thread. We don't want the user to see a different |
| 3283 | selected thread. */ |
| 3284 | switch_to_thread (cur_thr); |
| 3285 | |
| 3286 | /* Tell the event loop to wait for it to stop. If the target |
| 3287 | supports asynchronous execution, it'll do this from within |
| 3288 | target_resume. */ |
| 3289 | if (!target_can_async_p ()) |
| 3290 | mark_async_event_handler (infrun_async_inferior_event_token); |
| 3291 | } |
| 3292 | \f |
| 3293 | |
| 3294 | /* Start remote-debugging of a machine over a serial link. */ |
| 3295 | |
| 3296 | void |
| 3297 | start_remote (int from_tty) |
| 3298 | { |
| 3299 | inferior *inf = current_inferior (); |
| 3300 | inf->control.stop_soon = STOP_QUIETLY_REMOTE; |
| 3301 | |
| 3302 | /* Always go on waiting for the target, regardless of the mode. */ |
| 3303 | /* FIXME: cagney/1999-09-23: At present it isn't possible to |
| 3304 | indicate to wait_for_inferior that a target should timeout if |
| 3305 | nothing is returned (instead of just blocking). Because of this, |
| 3306 | targets expecting an immediate response need to, internally, set |
| 3307 | things up so that the target_wait() is forced to eventually |
| 3308 | timeout. */ |
| 3309 | /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to |
| 3310 | differentiate to its caller what the state of the target is after |
| 3311 | the initial open has been performed. Here we're assuming that |
| 3312 | the target has stopped. It should be possible to eventually have |
| 3313 | target_open() return to the caller an indication that the target |
| 3314 | is currently running and GDB state should be set to the same as |
| 3315 | for an async run. */ |
| 3316 | wait_for_inferior (inf); |
| 3317 | |
| 3318 | /* Now that the inferior has stopped, do any bookkeeping like |
| 3319 | loading shared libraries. We want to do this before normal_stop, |
| 3320 | so that the displayed frame is up to date. */ |
| 3321 | post_create_inferior (from_tty); |
| 3322 | |
| 3323 | normal_stop (); |
| 3324 | } |
| 3325 | |
| 3326 | /* Initialize static vars when a new inferior begins. */ |
| 3327 | |
| 3328 | void |
| 3329 | init_wait_for_inferior (void) |
| 3330 | { |
| 3331 | /* These are meaningless until the first time through wait_for_inferior. */ |
| 3332 | |
| 3333 | breakpoint_init_inferior (inf_starting); |
| 3334 | |
| 3335 | clear_proceed_status (0); |
| 3336 | |
| 3337 | nullify_last_target_wait_ptid (); |
| 3338 | |
| 3339 | previous_inferior_ptid = inferior_ptid; |
| 3340 | } |
| 3341 | |
| 3342 | \f |
| 3343 | |
| 3344 | static void handle_inferior_event (struct execution_control_state *ecs); |
| 3345 | |
| 3346 | static void handle_step_into_function (struct gdbarch *gdbarch, |
| 3347 | struct execution_control_state *ecs); |
| 3348 | static void handle_step_into_function_backward (struct gdbarch *gdbarch, |
| 3349 | struct execution_control_state *ecs); |
| 3350 | static void handle_signal_stop (struct execution_control_state *ecs); |
| 3351 | static void check_exception_resume (struct execution_control_state *, |
| 3352 | struct frame_info *); |
| 3353 | |
| 3354 | static void end_stepping_range (struct execution_control_state *ecs); |
| 3355 | static void stop_waiting (struct execution_control_state *ecs); |
| 3356 | static void keep_going (struct execution_control_state *ecs); |
| 3357 | static void process_event_stop_test (struct execution_control_state *ecs); |
| 3358 | static bool switch_back_to_stepped_thread (struct execution_control_state *ecs); |
| 3359 | |
| 3360 | /* This function is attached as a "thread_stop_requested" observer. |
| 3361 | Cleanup local state that assumed the PTID was to be resumed, and |
| 3362 | report the stop to the frontend. */ |
| 3363 | |
| 3364 | static void |
| 3365 | infrun_thread_stop_requested (ptid_t ptid) |
| 3366 | { |
| 3367 | process_stratum_target *curr_target = current_inferior ()->process_target (); |
| 3368 | |
| 3369 | /* PTID was requested to stop. If the thread was already stopped, |
| 3370 | but the user/frontend doesn't know about that yet (e.g., the |
| 3371 | thread had been temporarily paused for some step-over), set up |
| 3372 | for reporting the stop now. */ |
| 3373 | for (thread_info *tp : all_threads (curr_target, ptid)) |
| 3374 | { |
| 3375 | if (tp->state != THREAD_RUNNING) |
| 3376 | continue; |
| 3377 | if (tp->executing) |
| 3378 | continue; |
| 3379 | |
| 3380 | /* Remove matching threads from the step-over queue, so |
| 3381 | start_step_over doesn't try to resume them |
| 3382 | automatically. */ |
| 3383 | if (thread_is_in_step_over_chain (tp)) |
| 3384 | global_thread_step_over_chain_remove (tp); |
| 3385 | |
| 3386 | /* If the thread is stopped, but the user/frontend doesn't |
| 3387 | know about that yet, queue a pending event, as if the |
| 3388 | thread had just stopped now. Unless the thread already had |
| 3389 | a pending event. */ |
| 3390 | if (!tp->suspend.waitstatus_pending_p) |
| 3391 | { |
| 3392 | tp->suspend.waitstatus_pending_p = 1; |
| 3393 | tp->suspend.waitstatus.kind = TARGET_WAITKIND_STOPPED; |
| 3394 | tp->suspend.waitstatus.value.sig = GDB_SIGNAL_0; |
| 3395 | } |
| 3396 | |
| 3397 | /* Clear the inline-frame state, since we're re-processing the |
| 3398 | stop. */ |
| 3399 | clear_inline_frame_state (tp); |
| 3400 | |
| 3401 | /* If this thread was paused because some other thread was |
| 3402 | doing an inline-step over, let that finish first. Once |
| 3403 | that happens, we'll restart all threads and consume pending |
| 3404 | stop events then. */ |
| 3405 | if (step_over_info_valid_p ()) |
| 3406 | continue; |
| 3407 | |
| 3408 | /* Otherwise we can process the (new) pending event now. Set |
| 3409 | it so this pending event is considered by |
| 3410 | do_target_wait. */ |
| 3411 | tp->resumed = true; |
| 3412 | } |
| 3413 | } |
| 3414 | |
| 3415 | static void |
| 3416 | infrun_thread_thread_exit (struct thread_info *tp, int silent) |
| 3417 | { |
| 3418 | if (target_last_proc_target == tp->inf->process_target () |
| 3419 | && target_last_wait_ptid == tp->ptid) |
| 3420 | nullify_last_target_wait_ptid (); |
| 3421 | } |
| 3422 | |
| 3423 | /* Delete the step resume, single-step and longjmp/exception resume |
| 3424 | breakpoints of TP. */ |
| 3425 | |
| 3426 | static void |
| 3427 | delete_thread_infrun_breakpoints (struct thread_info *tp) |
| 3428 | { |
| 3429 | delete_step_resume_breakpoint (tp); |
| 3430 | delete_exception_resume_breakpoint (tp); |
| 3431 | delete_single_step_breakpoints (tp); |
| 3432 | } |
| 3433 | |
| 3434 | /* If the target still has execution, call FUNC for each thread that |
| 3435 | just stopped. In all-stop, that's all the non-exited threads; in |
| 3436 | non-stop, that's the current thread, only. */ |
| 3437 | |
| 3438 | typedef void (*for_each_just_stopped_thread_callback_func) |
| 3439 | (struct thread_info *tp); |
| 3440 | |
| 3441 | static void |
| 3442 | for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func) |
| 3443 | { |
| 3444 | if (!target_has_execution () || inferior_ptid == null_ptid) |
| 3445 | return; |
| 3446 | |
| 3447 | if (target_is_non_stop_p ()) |
| 3448 | { |
| 3449 | /* If in non-stop mode, only the current thread stopped. */ |
| 3450 | func (inferior_thread ()); |
| 3451 | } |
| 3452 | else |
| 3453 | { |
| 3454 | /* In all-stop mode, all threads have stopped. */ |
| 3455 | for (thread_info *tp : all_non_exited_threads ()) |
| 3456 | func (tp); |
| 3457 | } |
| 3458 | } |
| 3459 | |
| 3460 | /* Delete the step resume and longjmp/exception resume breakpoints of |
| 3461 | the threads that just stopped. */ |
| 3462 | |
| 3463 | static void |
| 3464 | delete_just_stopped_threads_infrun_breakpoints (void) |
| 3465 | { |
| 3466 | for_each_just_stopped_thread (delete_thread_infrun_breakpoints); |
| 3467 | } |
| 3468 | |
| 3469 | /* Delete the single-step breakpoints of the threads that just |
| 3470 | stopped. */ |
| 3471 | |
| 3472 | static void |
| 3473 | delete_just_stopped_threads_single_step_breakpoints (void) |
| 3474 | { |
| 3475 | for_each_just_stopped_thread (delete_single_step_breakpoints); |
| 3476 | } |
| 3477 | |
| 3478 | /* See infrun.h. */ |
| 3479 | |
| 3480 | void |
| 3481 | print_target_wait_results (ptid_t waiton_ptid, ptid_t result_ptid, |
| 3482 | const struct target_waitstatus *ws) |
| 3483 | { |
| 3484 | infrun_debug_printf ("target_wait (%d.%ld.%ld [%s], status) =", |
| 3485 | waiton_ptid.pid (), |
| 3486 | waiton_ptid.lwp (), |
| 3487 | waiton_ptid.tid (), |
| 3488 | target_pid_to_str (waiton_ptid).c_str ()); |
| 3489 | infrun_debug_printf (" %d.%ld.%ld [%s],", |
| 3490 | result_ptid.pid (), |
| 3491 | result_ptid.lwp (), |
| 3492 | result_ptid.tid (), |
| 3493 | target_pid_to_str (result_ptid).c_str ()); |
| 3494 | infrun_debug_printf (" %s", target_waitstatus_to_string (ws).c_str ()); |
| 3495 | } |
| 3496 | |
| 3497 | /* Select a thread at random, out of those which are resumed and have |
| 3498 | had events. */ |
| 3499 | |
| 3500 | static struct thread_info * |
| 3501 | random_pending_event_thread (inferior *inf, ptid_t waiton_ptid) |
| 3502 | { |
| 3503 | int num_events = 0; |
| 3504 | |
| 3505 | auto has_event = [&] (thread_info *tp) |
| 3506 | { |
| 3507 | return (tp->ptid.matches (waiton_ptid) |
| 3508 | && tp->resumed |
| 3509 | && tp->suspend.waitstatus_pending_p); |
| 3510 | }; |
| 3511 | |
| 3512 | /* First see how many events we have. Count only resumed threads |
| 3513 | that have an event pending. */ |
| 3514 | for (thread_info *tp : inf->non_exited_threads ()) |
| 3515 | if (has_event (tp)) |
| 3516 | num_events++; |
| 3517 | |
| 3518 | if (num_events == 0) |
| 3519 | return NULL; |
| 3520 | |
| 3521 | /* Now randomly pick a thread out of those that have had events. */ |
| 3522 | int random_selector = (int) ((num_events * (double) rand ()) |
| 3523 | / (RAND_MAX + 1.0)); |
| 3524 | |
| 3525 | if (num_events > 1) |
| 3526 | infrun_debug_printf ("Found %d events, selecting #%d", |
| 3527 | num_events, random_selector); |
| 3528 | |
| 3529 | /* Select the Nth thread that has had an event. */ |
| 3530 | for (thread_info *tp : inf->non_exited_threads ()) |
| 3531 | if (has_event (tp)) |
| 3532 | if (random_selector-- == 0) |
| 3533 | return tp; |
| 3534 | |
| 3535 | gdb_assert_not_reached ("event thread not found"); |
| 3536 | } |
| 3537 | |
| 3538 | /* Wrapper for target_wait that first checks whether threads have |
| 3539 | pending statuses to report before actually asking the target for |
| 3540 | more events. INF is the inferior we're using to call target_wait |
| 3541 | on. */ |
| 3542 | |
| 3543 | static ptid_t |
| 3544 | do_target_wait_1 (inferior *inf, ptid_t ptid, |
| 3545 | target_waitstatus *status, target_wait_flags options) |
| 3546 | { |
| 3547 | ptid_t event_ptid; |
| 3548 | struct thread_info *tp; |
| 3549 | |
| 3550 | /* We know that we are looking for an event in the target of inferior |
| 3551 | INF, but we don't know which thread the event might come from. As |
| 3552 | such we want to make sure that INFERIOR_PTID is reset so that none of |
| 3553 | the wait code relies on it - doing so is always a mistake. */ |
| 3554 | switch_to_inferior_no_thread (inf); |
| 3555 | |
| 3556 | /* First check if there is a resumed thread with a wait status |
| 3557 | pending. */ |
| 3558 | if (ptid == minus_one_ptid || ptid.is_pid ()) |
| 3559 | { |
| 3560 | tp = random_pending_event_thread (inf, ptid); |
| 3561 | } |
| 3562 | else |
| 3563 | { |
| 3564 | infrun_debug_printf ("Waiting for specific thread %s.", |
| 3565 | target_pid_to_str (ptid).c_str ()); |
| 3566 | |
| 3567 | /* We have a specific thread to check. */ |
| 3568 | tp = find_thread_ptid (inf, ptid); |
| 3569 | gdb_assert (tp != NULL); |
| 3570 | if (!tp->suspend.waitstatus_pending_p) |
| 3571 | tp = NULL; |
| 3572 | } |
| 3573 | |
| 3574 | if (tp != NULL |
| 3575 | && (tp->suspend.stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT |
| 3576 | || tp->suspend.stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT)) |
| 3577 | { |
| 3578 | struct regcache *regcache = get_thread_regcache (tp); |
| 3579 | struct gdbarch *gdbarch = regcache->arch (); |
| 3580 | CORE_ADDR pc; |
| 3581 | int discard = 0; |
| 3582 | |
| 3583 | pc = regcache_read_pc (regcache); |
| 3584 | |
| 3585 | if (pc != tp->suspend.stop_pc) |
| 3586 | { |
| 3587 | infrun_debug_printf ("PC of %s changed. was=%s, now=%s", |
| 3588 | target_pid_to_str (tp->ptid).c_str (), |
| 3589 | paddress (gdbarch, tp->suspend.stop_pc), |
| 3590 | paddress (gdbarch, pc)); |
| 3591 | discard = 1; |
| 3592 | } |
| 3593 | else if (!breakpoint_inserted_here_p (regcache->aspace (), pc)) |
| 3594 | { |
| 3595 | infrun_debug_printf ("previous breakpoint of %s, at %s gone", |
| 3596 | target_pid_to_str (tp->ptid).c_str (), |
| 3597 | paddress (gdbarch, pc)); |
| 3598 | |
| 3599 | discard = 1; |
| 3600 | } |
| 3601 | |
| 3602 | if (discard) |
| 3603 | { |
| 3604 | infrun_debug_printf ("pending event of %s cancelled.", |
| 3605 | target_pid_to_str (tp->ptid).c_str ()); |
| 3606 | |
| 3607 | tp->suspend.waitstatus.kind = TARGET_WAITKIND_SPURIOUS; |
| 3608 | tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON; |
| 3609 | } |
| 3610 | } |
| 3611 | |
| 3612 | if (tp != NULL) |
| 3613 | { |
| 3614 | infrun_debug_printf ("Using pending wait status %s for %s.", |
| 3615 | target_waitstatus_to_string |
| 3616 | (&tp->suspend.waitstatus).c_str (), |
| 3617 | target_pid_to_str (tp->ptid).c_str ()); |
| 3618 | |
| 3619 | /* Now that we've selected our final event LWP, un-adjust its PC |
| 3620 | if it was a software breakpoint (and the target doesn't |
| 3621 | always adjust the PC itself). */ |
| 3622 | if (tp->suspend.stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT |
| 3623 | && !target_supports_stopped_by_sw_breakpoint ()) |
| 3624 | { |
| 3625 | struct regcache *regcache; |
| 3626 | struct gdbarch *gdbarch; |
| 3627 | int decr_pc; |
| 3628 | |
| 3629 | regcache = get_thread_regcache (tp); |
| 3630 | gdbarch = regcache->arch (); |
| 3631 | |
| 3632 | decr_pc = gdbarch_decr_pc_after_break (gdbarch); |
| 3633 | if (decr_pc != 0) |
| 3634 | { |
| 3635 | CORE_ADDR pc; |
| 3636 | |
| 3637 | pc = regcache_read_pc (regcache); |
| 3638 | regcache_write_pc (regcache, pc + decr_pc); |
| 3639 | } |
| 3640 | } |
| 3641 | |
| 3642 | tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON; |
| 3643 | *status = tp->suspend.waitstatus; |
| 3644 | tp->suspend.waitstatus_pending_p = 0; |
| 3645 | |
| 3646 | /* Wake up the event loop again, until all pending events are |
| 3647 | processed. */ |
| 3648 | if (target_is_async_p ()) |
| 3649 | mark_async_event_handler (infrun_async_inferior_event_token); |
| 3650 | return tp->ptid; |
| 3651 | } |
| 3652 | |
| 3653 | /* But if we don't find one, we'll have to wait. */ |
| 3654 | |
| 3655 | /* We can't ask a non-async target to do a non-blocking wait, so this will be |
| 3656 | a blocking wait. */ |
| 3657 | if (!target_can_async_p ()) |
| 3658 | options &= ~TARGET_WNOHANG; |
| 3659 | |
| 3660 | if (deprecated_target_wait_hook) |
| 3661 | event_ptid = deprecated_target_wait_hook (ptid, status, options); |
| 3662 | else |
| 3663 | event_ptid = target_wait (ptid, status, options); |
| 3664 | |
| 3665 | return event_ptid; |
| 3666 | } |
| 3667 | |
| 3668 | /* Wrapper for target_wait that first checks whether threads have |
| 3669 | pending statuses to report before actually asking the target for |
| 3670 | more events. Polls for events from all inferiors/targets. */ |
| 3671 | |
| 3672 | static bool |
| 3673 | do_target_wait (execution_control_state *ecs, target_wait_flags options) |
| 3674 | { |
| 3675 | int num_inferiors = 0; |
| 3676 | int random_selector; |
| 3677 | |
| 3678 | /* For fairness, we pick the first inferior/target to poll at random |
| 3679 | out of all inferiors that may report events, and then continue |
| 3680 | polling the rest of the inferior list starting from that one in a |
| 3681 | circular fashion until the whole list is polled once. */ |
| 3682 | |
| 3683 | auto inferior_matches = [] (inferior *inf) |
| 3684 | { |
| 3685 | return inf->process_target () != nullptr; |
| 3686 | }; |
| 3687 | |
| 3688 | /* First see how many matching inferiors we have. */ |
| 3689 | for (inferior *inf : all_inferiors ()) |
| 3690 | if (inferior_matches (inf)) |
| 3691 | num_inferiors++; |
| 3692 | |
| 3693 | if (num_inferiors == 0) |
| 3694 | { |
| 3695 | ecs->ws.kind = TARGET_WAITKIND_IGNORE; |
| 3696 | return false; |
| 3697 | } |
| 3698 | |
| 3699 | /* Now randomly pick an inferior out of those that matched. */ |
| 3700 | random_selector = (int) |
| 3701 | ((num_inferiors * (double) rand ()) / (RAND_MAX + 1.0)); |
| 3702 | |
| 3703 | if (num_inferiors > 1) |
| 3704 | infrun_debug_printf ("Found %d inferiors, starting at #%d", |
| 3705 | num_inferiors, random_selector); |
| 3706 | |
| 3707 | /* Select the Nth inferior that matched. */ |
| 3708 | |
| 3709 | inferior *selected = nullptr; |
| 3710 | |
| 3711 | for (inferior *inf : all_inferiors ()) |
| 3712 | if (inferior_matches (inf)) |
| 3713 | if (random_selector-- == 0) |
| 3714 | { |
| 3715 | selected = inf; |
| 3716 | break; |
| 3717 | } |
| 3718 | |
| 3719 | /* Now poll for events out of each of the matching inferior's |
| 3720 | targets, starting from the selected one. */ |
| 3721 | |
| 3722 | auto do_wait = [&] (inferior *inf) |
| 3723 | { |
| 3724 | ecs->ptid = do_target_wait_1 (inf, minus_one_ptid, &ecs->ws, options); |
| 3725 | ecs->target = inf->process_target (); |
| 3726 | return (ecs->ws.kind != TARGET_WAITKIND_IGNORE); |
| 3727 | }; |
| 3728 | |
| 3729 | /* Needed in 'all-stop + target-non-stop' mode, because we end up |
| 3730 | here spuriously after the target is all stopped and we've already |
| 3731 | reported the stop to the user, polling for events. */ |
| 3732 | scoped_restore_current_thread restore_thread; |
| 3733 | |
| 3734 | int inf_num = selected->num; |
| 3735 | for (inferior *inf = selected; inf != NULL; inf = inf->next) |
| 3736 | if (inferior_matches (inf)) |
| 3737 | if (do_wait (inf)) |
| 3738 | return true; |
| 3739 | |
| 3740 | for (inferior *inf = inferior_list; |
| 3741 | inf != NULL && inf->num < inf_num; |
| 3742 | inf = inf->next) |
| 3743 | if (inferior_matches (inf)) |
| 3744 | if (do_wait (inf)) |
| 3745 | return true; |
| 3746 | |
| 3747 | ecs->ws.kind = TARGET_WAITKIND_IGNORE; |
| 3748 | return false; |
| 3749 | } |
| 3750 | |
| 3751 | /* An event reported by wait_one. */ |
| 3752 | |
| 3753 | struct wait_one_event |
| 3754 | { |
| 3755 | /* The target the event came out of. */ |
| 3756 | process_stratum_target *target; |
| 3757 | |
| 3758 | /* The PTID the event was for. */ |
| 3759 | ptid_t ptid; |
| 3760 | |
| 3761 | /* The waitstatus. */ |
| 3762 | target_waitstatus ws; |
| 3763 | }; |
| 3764 | |
| 3765 | static bool handle_one (const wait_one_event &event); |
| 3766 | static void restart_threads (struct thread_info *event_thread); |
| 3767 | |
| 3768 | /* Prepare and stabilize the inferior for detaching it. E.g., |
| 3769 | detaching while a thread is displaced stepping is a recipe for |
| 3770 | crashing it, as nothing would readjust the PC out of the scratch |
| 3771 | pad. */ |
| 3772 | |
| 3773 | void |
| 3774 | prepare_for_detach (void) |
| 3775 | { |
| 3776 | struct inferior *inf = current_inferior (); |
| 3777 | ptid_t pid_ptid = ptid_t (inf->pid); |
| 3778 | scoped_restore_current_thread restore_thread; |
| 3779 | |
| 3780 | scoped_restore restore_detaching = make_scoped_restore (&inf->detaching, true); |
| 3781 | |
| 3782 | /* Remove all threads of INF from the global step-over chain. We |
| 3783 | want to stop any ongoing step-over, not start any new one. */ |
| 3784 | thread_info *next; |
| 3785 | for (thread_info *tp = global_thread_step_over_chain_head; |
| 3786 | tp != nullptr; |
| 3787 | tp = next) |
| 3788 | { |
| 3789 | next = global_thread_step_over_chain_next (tp); |
| 3790 | if (tp->inf == inf) |
| 3791 | global_thread_step_over_chain_remove (tp); |
| 3792 | } |
| 3793 | |
| 3794 | /* If we were already in the middle of an inline step-over, and the |
| 3795 | thread stepping belongs to the inferior we're detaching, we need |
| 3796 | to restart the threads of other inferiors. */ |
| 3797 | if (step_over_info.thread != -1) |
| 3798 | { |
| 3799 | infrun_debug_printf ("inline step-over in-process while detaching"); |
| 3800 | |
| 3801 | thread_info *thr = find_thread_global_id (step_over_info.thread); |
| 3802 | if (thr->inf == inf) |
| 3803 | { |
| 3804 | /* Since we removed threads of INF from the step-over chain, |
| 3805 | we know this won't start a step-over for INF. */ |
| 3806 | clear_step_over_info (); |
| 3807 | |
| 3808 | if (target_is_non_stop_p ()) |
| 3809 | { |
| 3810 | /* Start a new step-over in another thread if there's |
| 3811 | one that needs it. */ |
| 3812 | start_step_over (); |
| 3813 | |
| 3814 | /* Restart all other threads (except the |
| 3815 | previously-stepping thread, since that one is still |
| 3816 | running). */ |
| 3817 | if (!step_over_info_valid_p ()) |
| 3818 | restart_threads (thr); |
| 3819 | } |
| 3820 | } |
| 3821 | } |
| 3822 | |
| 3823 | if (displaced_step_in_progress (inf)) |
| 3824 | { |
| 3825 | infrun_debug_printf ("displaced-stepping in-process while detaching"); |
| 3826 | |
| 3827 | /* Stop threads currently displaced stepping, aborting it. */ |
| 3828 | |
| 3829 | for (thread_info *thr : inf->non_exited_threads ()) |
| 3830 | { |
| 3831 | if (thr->displaced_step_state.in_progress ()) |
| 3832 | { |
| 3833 | if (thr->executing) |
| 3834 | { |
| 3835 | if (!thr->stop_requested) |
| 3836 | { |
| 3837 | target_stop (thr->ptid); |
| 3838 | thr->stop_requested = true; |
| 3839 | } |
| 3840 | } |
| 3841 | else |
| 3842 | thr->resumed = false; |
| 3843 | } |
| 3844 | } |
| 3845 | |
| 3846 | while (displaced_step_in_progress (inf)) |
| 3847 | { |
| 3848 | wait_one_event event; |
| 3849 | |
| 3850 | event.target = inf->process_target (); |
| 3851 | event.ptid = do_target_wait_1 (inf, pid_ptid, &event.ws, 0); |
| 3852 | |
| 3853 | if (debug_infrun) |
| 3854 | print_target_wait_results (pid_ptid, event.ptid, &event.ws); |
| 3855 | |
| 3856 | handle_one (event); |
| 3857 | } |
| 3858 | |
| 3859 | /* It's OK to leave some of the threads of INF stopped, since |
| 3860 | they'll be detached shortly. */ |
| 3861 | } |
| 3862 | } |
| 3863 | |
| 3864 | /* Wait for control to return from inferior to debugger. |
| 3865 | |
| 3866 | If inferior gets a signal, we may decide to start it up again |
| 3867 | instead of returning. That is why there is a loop in this function. |
| 3868 | When this function actually returns it means the inferior |
| 3869 | should be left stopped and GDB should read more commands. */ |
| 3870 | |
| 3871 | static void |
| 3872 | wait_for_inferior (inferior *inf) |
| 3873 | { |
| 3874 | infrun_debug_printf ("wait_for_inferior ()"); |
| 3875 | |
| 3876 | SCOPE_EXIT { delete_just_stopped_threads_infrun_breakpoints (); }; |
| 3877 | |
| 3878 | /* If an error happens while handling the event, propagate GDB's |
| 3879 | knowledge of the executing state to the frontend/user running |
| 3880 | state. */ |
| 3881 | scoped_finish_thread_state finish_state |
| 3882 | (inf->process_target (), minus_one_ptid); |
| 3883 | |
| 3884 | while (1) |
| 3885 | { |
| 3886 | struct execution_control_state ecss; |
| 3887 | struct execution_control_state *ecs = &ecss; |
| 3888 | |
| 3889 | memset (ecs, 0, sizeof (*ecs)); |
| 3890 | |
| 3891 | overlay_cache_invalid = 1; |
| 3892 | |
| 3893 | /* Flush target cache before starting to handle each event. |
| 3894 | Target was running and cache could be stale. This is just a |
| 3895 | heuristic. Running threads may modify target memory, but we |
| 3896 | don't get any event. */ |
| 3897 | target_dcache_invalidate (); |
| 3898 | |
| 3899 | ecs->ptid = do_target_wait_1 (inf, minus_one_ptid, &ecs->ws, 0); |
| 3900 | ecs->target = inf->process_target (); |
| 3901 | |
| 3902 | if (debug_infrun) |
| 3903 | print_target_wait_results (minus_one_ptid, ecs->ptid, &ecs->ws); |
| 3904 | |
| 3905 | /* Now figure out what to do with the result of the result. */ |
| 3906 | handle_inferior_event (ecs); |
| 3907 | |
| 3908 | if (!ecs->wait_some_more) |
| 3909 | break; |
| 3910 | } |
| 3911 | |
| 3912 | /* No error, don't finish the state yet. */ |
| 3913 | finish_state.release (); |
| 3914 | } |
| 3915 | |
| 3916 | /* Cleanup that reinstalls the readline callback handler, if the |
| 3917 | target is running in the background. If while handling the target |
| 3918 | event something triggered a secondary prompt, like e.g., a |
| 3919 | pagination prompt, we'll have removed the callback handler (see |
| 3920 | gdb_readline_wrapper_line). Need to do this as we go back to the |
| 3921 | event loop, ready to process further input. Note this has no |
| 3922 | effect if the handler hasn't actually been removed, because calling |
| 3923 | rl_callback_handler_install resets the line buffer, thus losing |
| 3924 | input. */ |
| 3925 | |
| 3926 | static void |
| 3927 | reinstall_readline_callback_handler_cleanup () |
| 3928 | { |
| 3929 | struct ui *ui = current_ui; |
| 3930 | |
| 3931 | if (!ui->async) |
| 3932 | { |
| 3933 | /* We're not going back to the top level event loop yet. Don't |
| 3934 | install the readline callback, as it'd prep the terminal, |
| 3935 | readline-style (raw, noecho) (e.g., --batch). We'll install |
| 3936 | it the next time the prompt is displayed, when we're ready |
| 3937 | for input. */ |
| 3938 | return; |
| 3939 | } |
| 3940 | |
| 3941 | if (ui->command_editing && ui->prompt_state != PROMPT_BLOCKED) |
| 3942 | gdb_rl_callback_handler_reinstall (); |
| 3943 | } |
| 3944 | |
| 3945 | /* Clean up the FSMs of threads that are now stopped. In non-stop, |
| 3946 | that's just the event thread. In all-stop, that's all threads. */ |
| 3947 | |
| 3948 | static void |
| 3949 | clean_up_just_stopped_threads_fsms (struct execution_control_state *ecs) |
| 3950 | { |
| 3951 | if (ecs->event_thread != NULL |
| 3952 | && ecs->event_thread->thread_fsm != NULL) |
| 3953 | ecs->event_thread->thread_fsm->clean_up (ecs->event_thread); |
| 3954 | |
| 3955 | if (!non_stop) |
| 3956 | { |
| 3957 | for (thread_info *thr : all_non_exited_threads ()) |
| 3958 | { |
| 3959 | if (thr->thread_fsm == NULL) |
| 3960 | continue; |
| 3961 | if (thr == ecs->event_thread) |
| 3962 | continue; |
| 3963 | |
| 3964 | switch_to_thread (thr); |
| 3965 | thr->thread_fsm->clean_up (thr); |
| 3966 | } |
| 3967 | |
| 3968 | if (ecs->event_thread != NULL) |
| 3969 | switch_to_thread (ecs->event_thread); |
| 3970 | } |
| 3971 | } |
| 3972 | |
| 3973 | /* Helper for all_uis_check_sync_execution_done that works on the |
| 3974 | current UI. */ |
| 3975 | |
| 3976 | static void |
| 3977 | check_curr_ui_sync_execution_done (void) |
| 3978 | { |
| 3979 | struct ui *ui = current_ui; |
| 3980 | |
| 3981 | if (ui->prompt_state == PROMPT_NEEDED |
| 3982 | && ui->async |
| 3983 | && !gdb_in_secondary_prompt_p (ui)) |
| 3984 | { |
| 3985 | target_terminal::ours (); |
| 3986 | gdb::observers::sync_execution_done.notify (); |
| 3987 | ui_register_input_event_handler (ui); |
| 3988 | } |
| 3989 | } |
| 3990 | |
| 3991 | /* See infrun.h. */ |
| 3992 | |
| 3993 | void |
| 3994 | all_uis_check_sync_execution_done (void) |
| 3995 | { |
| 3996 | SWITCH_THRU_ALL_UIS () |
| 3997 | { |
| 3998 | check_curr_ui_sync_execution_done (); |
| 3999 | } |
| 4000 | } |
| 4001 | |
| 4002 | /* See infrun.h. */ |
| 4003 | |
| 4004 | void |
| 4005 | all_uis_on_sync_execution_starting (void) |
| 4006 | { |
| 4007 | SWITCH_THRU_ALL_UIS () |
| 4008 | { |
| 4009 | if (current_ui->prompt_state == PROMPT_NEEDED) |
| 4010 | async_disable_stdin (); |
| 4011 | } |
| 4012 | } |
| 4013 | |
| 4014 | /* Asynchronous version of wait_for_inferior. It is called by the |
| 4015 | event loop whenever a change of state is detected on the file |
| 4016 | descriptor corresponding to the target. It can be called more than |
| 4017 | once to complete a single execution command. In such cases we need |
| 4018 | to keep the state in a global variable ECSS. If it is the last time |
| 4019 | that this function is called for a single execution command, then |
| 4020 | report to the user that the inferior has stopped, and do the |
| 4021 | necessary cleanups. */ |
| 4022 | |
| 4023 | void |
| 4024 | fetch_inferior_event () |
| 4025 | { |
| 4026 | INFRUN_SCOPED_DEBUG_ENTER_EXIT; |
| 4027 | |
| 4028 | struct execution_control_state ecss; |
| 4029 | struct execution_control_state *ecs = &ecss; |
| 4030 | int cmd_done = 0; |
| 4031 | |
| 4032 | memset (ecs, 0, sizeof (*ecs)); |
| 4033 | |
| 4034 | /* Events are always processed with the main UI as current UI. This |
| 4035 | way, warnings, debug output, etc. are always consistently sent to |
| 4036 | the main console. */ |
| 4037 | scoped_restore save_ui = make_scoped_restore (¤t_ui, main_ui); |
| 4038 | |
| 4039 | /* Temporarily disable pagination. Otherwise, the user would be |
| 4040 | given an option to press 'q' to quit, which would cause an early |
| 4041 | exit and could leave GDB in a half-baked state. */ |
| 4042 | scoped_restore save_pagination |
| 4043 | = make_scoped_restore (&pagination_enabled, false); |
| 4044 | |
| 4045 | /* End up with readline processing input, if necessary. */ |
| 4046 | { |
| 4047 | SCOPE_EXIT { reinstall_readline_callback_handler_cleanup (); }; |
| 4048 | |
| 4049 | /* We're handling a live event, so make sure we're doing live |
| 4050 | debugging. If we're looking at traceframes while the target is |
| 4051 | running, we're going to need to get back to that mode after |
| 4052 | handling the event. */ |
| 4053 | gdb::optional<scoped_restore_current_traceframe> maybe_restore_traceframe; |
| 4054 | if (non_stop) |
| 4055 | { |
| 4056 | maybe_restore_traceframe.emplace (); |
| 4057 | set_current_traceframe (-1); |
| 4058 | } |
| 4059 | |
| 4060 | /* The user/frontend should not notice a thread switch due to |
| 4061 | internal events. Make sure we revert to the user selected |
| 4062 | thread and frame after handling the event and running any |
| 4063 | breakpoint commands. */ |
| 4064 | scoped_restore_current_thread restore_thread; |
| 4065 | |
| 4066 | overlay_cache_invalid = 1; |
| 4067 | /* Flush target cache before starting to handle each event. Target |
| 4068 | was running and cache could be stale. This is just a heuristic. |
| 4069 | Running threads may modify target memory, but we don't get any |
| 4070 | event. */ |
| 4071 | target_dcache_invalidate (); |
| 4072 | |
| 4073 | scoped_restore save_exec_dir |
| 4074 | = make_scoped_restore (&execution_direction, |
| 4075 | target_execution_direction ()); |
| 4076 | |
| 4077 | /* Allow targets to pause their resumed threads while we handle |
| 4078 | the event. */ |
| 4079 | scoped_disable_commit_resumed disable_commit_resumed ("handling event"); |
| 4080 | |
| 4081 | if (!do_target_wait (ecs, TARGET_WNOHANG)) |
| 4082 | { |
| 4083 | infrun_debug_printf ("do_target_wait returned no event"); |
| 4084 | disable_commit_resumed.reset_and_commit (); |
| 4085 | return; |
| 4086 | } |
| 4087 | |
| 4088 | gdb_assert (ecs->ws.kind != TARGET_WAITKIND_IGNORE); |
| 4089 | |
| 4090 | /* Switch to the target that generated the event, so we can do |
| 4091 | target calls. */ |
| 4092 | switch_to_target_no_thread (ecs->target); |
| 4093 | |
| 4094 | if (debug_infrun) |
| 4095 | print_target_wait_results (minus_one_ptid, ecs->ptid, &ecs->ws); |
| 4096 | |
| 4097 | /* If an error happens while handling the event, propagate GDB's |
| 4098 | knowledge of the executing state to the frontend/user running |
| 4099 | state. */ |
| 4100 | ptid_t finish_ptid = !target_is_non_stop_p () ? minus_one_ptid : ecs->ptid; |
| 4101 | scoped_finish_thread_state finish_state (ecs->target, finish_ptid); |
| 4102 | |
| 4103 | /* Get executed before scoped_restore_current_thread above to apply |
| 4104 | still for the thread which has thrown the exception. */ |
| 4105 | auto defer_bpstat_clear |
| 4106 | = make_scope_exit (bpstat_clear_actions); |
| 4107 | auto defer_delete_threads |
| 4108 | = make_scope_exit (delete_just_stopped_threads_infrun_breakpoints); |
| 4109 | |
| 4110 | /* Now figure out what to do with the result of the result. */ |
| 4111 | handle_inferior_event (ecs); |
| 4112 | |
| 4113 | if (!ecs->wait_some_more) |
| 4114 | { |
| 4115 | struct inferior *inf = find_inferior_ptid (ecs->target, ecs->ptid); |
| 4116 | bool should_stop = true; |
| 4117 | struct thread_info *thr = ecs->event_thread; |
| 4118 | |
| 4119 | delete_just_stopped_threads_infrun_breakpoints (); |
| 4120 | |
| 4121 | if (thr != NULL) |
| 4122 | { |
| 4123 | struct thread_fsm *thread_fsm = thr->thread_fsm; |
| 4124 | |
| 4125 | if (thread_fsm != NULL) |
| 4126 | should_stop = thread_fsm->should_stop (thr); |
| 4127 | } |
| 4128 | |
| 4129 | if (!should_stop) |
| 4130 | { |
| 4131 | keep_going (ecs); |
| 4132 | } |
| 4133 | else |
| 4134 | { |
| 4135 | bool should_notify_stop = true; |
| 4136 | int proceeded = 0; |
| 4137 | |
| 4138 | clean_up_just_stopped_threads_fsms (ecs); |
| 4139 | |
| 4140 | if (thr != NULL && thr->thread_fsm != NULL) |
| 4141 | should_notify_stop = thr->thread_fsm->should_notify_stop (); |
| 4142 | |
| 4143 | if (should_notify_stop) |
| 4144 | { |
| 4145 | /* We may not find an inferior if this was a process exit. */ |
| 4146 | if (inf == NULL || inf->control.stop_soon == NO_STOP_QUIETLY) |
| 4147 | proceeded = normal_stop (); |
| 4148 | } |
| 4149 | |
| 4150 | if (!proceeded) |
| 4151 | { |
| 4152 | inferior_event_handler (INF_EXEC_COMPLETE); |
| 4153 | cmd_done = 1; |
| 4154 | } |
| 4155 | |
| 4156 | /* If we got a TARGET_WAITKIND_NO_RESUMED event, then the |
| 4157 | previously selected thread is gone. We have two |
| 4158 | choices - switch to no thread selected, or restore the |
| 4159 | previously selected thread (now exited). We chose the |
| 4160 | later, just because that's what GDB used to do. After |
| 4161 | this, "info threads" says "The current thread <Thread |
| 4162 | ID 2> has terminated." instead of "No thread |
| 4163 | selected.". */ |
| 4164 | if (!non_stop |
| 4165 | && cmd_done |
| 4166 | && ecs->ws.kind != TARGET_WAITKIND_NO_RESUMED) |
| 4167 | restore_thread.dont_restore (); |
| 4168 | } |
| 4169 | } |
| 4170 | |
| 4171 | defer_delete_threads.release (); |
| 4172 | defer_bpstat_clear.release (); |
| 4173 | |
| 4174 | /* No error, don't finish the thread states yet. */ |
| 4175 | finish_state.release (); |
| 4176 | |
| 4177 | disable_commit_resumed.reset_and_commit (); |
| 4178 | |
| 4179 | /* This scope is used to ensure that readline callbacks are |
| 4180 | reinstalled here. */ |
| 4181 | } |
| 4182 | |
| 4183 | /* If a UI was in sync execution mode, and now isn't, restore its |
| 4184 | prompt (a synchronous execution command has finished, and we're |
| 4185 | ready for input). */ |
| 4186 | all_uis_check_sync_execution_done (); |
| 4187 | |
| 4188 | if (cmd_done |
| 4189 | && exec_done_display_p |
| 4190 | && (inferior_ptid == null_ptid |
| 4191 | || inferior_thread ()->state != THREAD_RUNNING)) |
| 4192 | printf_unfiltered (_("completed.\n")); |
| 4193 | } |
| 4194 | |
| 4195 | /* See infrun.h. */ |
| 4196 | |
| 4197 | void |
| 4198 | set_step_info (thread_info *tp, struct frame_info *frame, |
| 4199 | struct symtab_and_line sal) |
| 4200 | { |
| 4201 | /* This can be removed once this function no longer implicitly relies on the |
| 4202 | inferior_ptid value. */ |
| 4203 | gdb_assert (inferior_ptid == tp->ptid); |
| 4204 | |
| 4205 | tp->control.step_frame_id = get_frame_id (frame); |
| 4206 | tp->control.step_stack_frame_id = get_stack_frame_id (frame); |
| 4207 | |
| 4208 | tp->current_symtab = sal.symtab; |
| 4209 | tp->current_line = sal.line; |
| 4210 | } |
| 4211 | |
| 4212 | /* Clear context switchable stepping state. */ |
| 4213 | |
| 4214 | void |
| 4215 | init_thread_stepping_state (struct thread_info *tss) |
| 4216 | { |
| 4217 | tss->stepped_breakpoint = 0; |
| 4218 | tss->stepping_over_breakpoint = 0; |
| 4219 | tss->stepping_over_watchpoint = 0; |
| 4220 | tss->step_after_step_resume_breakpoint = 0; |
| 4221 | } |
| 4222 | |
| 4223 | /* See infrun.h. */ |
| 4224 | |
| 4225 | void |
| 4226 | set_last_target_status (process_stratum_target *target, ptid_t ptid, |
| 4227 | target_waitstatus status) |
| 4228 | { |
| 4229 | target_last_proc_target = target; |
| 4230 | target_last_wait_ptid = ptid; |
| 4231 | target_last_waitstatus = status; |
| 4232 | } |
| 4233 | |
| 4234 | /* See infrun.h. */ |
| 4235 | |
| 4236 | void |
| 4237 | get_last_target_status (process_stratum_target **target, ptid_t *ptid, |
| 4238 | target_waitstatus *status) |
| 4239 | { |
| 4240 | if (target != nullptr) |
| 4241 | *target = target_last_proc_target; |
| 4242 | if (ptid != nullptr) |
| 4243 | *ptid = target_last_wait_ptid; |
| 4244 | if (status != nullptr) |
| 4245 | *status = target_last_waitstatus; |
| 4246 | } |
| 4247 | |
| 4248 | /* See infrun.h. */ |
| 4249 | |
| 4250 | void |
| 4251 | nullify_last_target_wait_ptid (void) |
| 4252 | { |
| 4253 | target_last_proc_target = nullptr; |
| 4254 | target_last_wait_ptid = minus_one_ptid; |
| 4255 | target_last_waitstatus = {}; |
| 4256 | } |
| 4257 | |
| 4258 | /* Switch thread contexts. */ |
| 4259 | |
| 4260 | static void |
| 4261 | context_switch (execution_control_state *ecs) |
| 4262 | { |
| 4263 | if (ecs->ptid != inferior_ptid |
| 4264 | && (inferior_ptid == null_ptid |
| 4265 | || ecs->event_thread != inferior_thread ())) |
| 4266 | { |
| 4267 | infrun_debug_printf ("Switching context from %s to %s", |
| 4268 | target_pid_to_str (inferior_ptid).c_str (), |
| 4269 | target_pid_to_str (ecs->ptid).c_str ()); |
| 4270 | } |
| 4271 | |
| 4272 | switch_to_thread (ecs->event_thread); |
| 4273 | } |
| 4274 | |
| 4275 | /* If the target can't tell whether we've hit breakpoints |
| 4276 | (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP, |
| 4277 | check whether that could have been caused by a breakpoint. If so, |
| 4278 | adjust the PC, per gdbarch_decr_pc_after_break. */ |
| 4279 | |
| 4280 | static void |
| 4281 | adjust_pc_after_break (struct thread_info *thread, |
| 4282 | struct target_waitstatus *ws) |
| 4283 | { |
| 4284 | struct regcache *regcache; |
| 4285 | struct gdbarch *gdbarch; |
| 4286 | CORE_ADDR breakpoint_pc, decr_pc; |
| 4287 | |
| 4288 | /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If |
| 4289 | we aren't, just return. |
| 4290 | |
| 4291 | We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not |
| 4292 | affected by gdbarch_decr_pc_after_break. Other waitkinds which are |
| 4293 | implemented by software breakpoints should be handled through the normal |
| 4294 | breakpoint layer. |
| 4295 | |
| 4296 | NOTE drow/2004-01-31: On some targets, breakpoints may generate |
| 4297 | different signals (SIGILL or SIGEMT for instance), but it is less |
| 4298 | clear where the PC is pointing afterwards. It may not match |
| 4299 | gdbarch_decr_pc_after_break. I don't know any specific target that |
| 4300 | generates these signals at breakpoints (the code has been in GDB since at |
| 4301 | least 1992) so I can not guess how to handle them here. |
| 4302 | |
| 4303 | In earlier versions of GDB, a target with |
| 4304 | gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a |
| 4305 | watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any |
| 4306 | target with both of these set in GDB history, and it seems unlikely to be |
| 4307 | correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */ |
| 4308 | |
| 4309 | if (ws->kind != TARGET_WAITKIND_STOPPED) |
| 4310 | return; |
| 4311 | |
| 4312 | if (ws->value.sig != GDB_SIGNAL_TRAP) |
| 4313 | return; |
| 4314 | |
| 4315 | /* In reverse execution, when a breakpoint is hit, the instruction |
| 4316 | under it has already been de-executed. The reported PC always |
| 4317 | points at the breakpoint address, so adjusting it further would |
| 4318 | be wrong. E.g., consider this case on a decr_pc_after_break == 1 |
| 4319 | architecture: |
| 4320 | |
| 4321 | B1 0x08000000 : INSN1 |
| 4322 | B2 0x08000001 : INSN2 |
| 4323 | 0x08000002 : INSN3 |
| 4324 | PC -> 0x08000003 : INSN4 |
| 4325 | |
| 4326 | Say you're stopped at 0x08000003 as above. Reverse continuing |
| 4327 | from that point should hit B2 as below. Reading the PC when the |
| 4328 | SIGTRAP is reported should read 0x08000001 and INSN2 should have |
| 4329 | been de-executed already. |
| 4330 | |
| 4331 | B1 0x08000000 : INSN1 |
| 4332 | B2 PC -> 0x08000001 : INSN2 |
| 4333 | 0x08000002 : INSN3 |
| 4334 | 0x08000003 : INSN4 |
| 4335 | |
| 4336 | We can't apply the same logic as for forward execution, because |
| 4337 | we would wrongly adjust the PC to 0x08000000, since there's a |
| 4338 | breakpoint at PC - 1. We'd then report a hit on B1, although |
| 4339 | INSN1 hadn't been de-executed yet. Doing nothing is the correct |
| 4340 | behaviour. */ |
| 4341 | if (execution_direction == EXEC_REVERSE) |
| 4342 | return; |
| 4343 | |
| 4344 | /* If the target can tell whether the thread hit a SW breakpoint, |
| 4345 | trust it. Targets that can tell also adjust the PC |
| 4346 | themselves. */ |
| 4347 | if (target_supports_stopped_by_sw_breakpoint ()) |
| 4348 | return; |
| 4349 | |
| 4350 | /* Note that relying on whether a breakpoint is planted in memory to |
| 4351 | determine this can fail. E.g,. the breakpoint could have been |
| 4352 | removed since. Or the thread could have been told to step an |
| 4353 | instruction the size of a breakpoint instruction, and only |
| 4354 | _after_ was a breakpoint inserted at its address. */ |
| 4355 | |
| 4356 | /* If this target does not decrement the PC after breakpoints, then |
| 4357 | we have nothing to do. */ |
| 4358 | regcache = get_thread_regcache (thread); |
| 4359 | gdbarch = regcache->arch (); |
| 4360 | |
| 4361 | decr_pc = gdbarch_decr_pc_after_break (gdbarch); |
| 4362 | if (decr_pc == 0) |
| 4363 | return; |
| 4364 | |
| 4365 | const address_space *aspace = regcache->aspace (); |
| 4366 | |
| 4367 | /* Find the location where (if we've hit a breakpoint) the |
| 4368 | breakpoint would be. */ |
| 4369 | breakpoint_pc = regcache_read_pc (regcache) - decr_pc; |
| 4370 | |
| 4371 | /* If the target can't tell whether a software breakpoint triggered, |
| 4372 | fallback to figuring it out based on breakpoints we think were |
| 4373 | inserted in the target, and on whether the thread was stepped or |
| 4374 | continued. */ |
| 4375 | |
| 4376 | /* Check whether there actually is a software breakpoint inserted at |
| 4377 | that location. |
| 4378 | |
| 4379 | If in non-stop mode, a race condition is possible where we've |
| 4380 | removed a breakpoint, but stop events for that breakpoint were |
| 4381 | already queued and arrive later. To suppress those spurious |
| 4382 | SIGTRAPs, we keep a list of such breakpoint locations for a bit, |
| 4383 | and retire them after a number of stop events are reported. Note |
| 4384 | this is an heuristic and can thus get confused. The real fix is |
| 4385 | to get the "stopped by SW BP and needs adjustment" info out of |
| 4386 | the target/kernel (and thus never reach here; see above). */ |
| 4387 | if (software_breakpoint_inserted_here_p (aspace, breakpoint_pc) |
| 4388 | || (target_is_non_stop_p () |
| 4389 | && moribund_breakpoint_here_p (aspace, breakpoint_pc))) |
| 4390 | { |
| 4391 | gdb::optional<scoped_restore_tmpl<int>> restore_operation_disable; |
| 4392 | |
| 4393 | if (record_full_is_used ()) |
| 4394 | restore_operation_disable.emplace |
| 4395 | (record_full_gdb_operation_disable_set ()); |
| 4396 | |
| 4397 | /* When using hardware single-step, a SIGTRAP is reported for both |
| 4398 | a completed single-step and a software breakpoint. Need to |
| 4399 | differentiate between the two, as the latter needs adjusting |
| 4400 | but the former does not. |
| 4401 | |
| 4402 | The SIGTRAP can be due to a completed hardware single-step only if |
| 4403 | - we didn't insert software single-step breakpoints |
| 4404 | - this thread is currently being stepped |
| 4405 | |
| 4406 | If any of these events did not occur, we must have stopped due |
| 4407 | to hitting a software breakpoint, and have to back up to the |
| 4408 | breakpoint address. |
| 4409 | |
| 4410 | As a special case, we could have hardware single-stepped a |
| 4411 | software breakpoint. In this case (prev_pc == breakpoint_pc), |
| 4412 | we also need to back up to the breakpoint address. */ |
| 4413 | |
| 4414 | if (thread_has_single_step_breakpoints_set (thread) |
| 4415 | || !currently_stepping (thread) |
| 4416 | || (thread->stepped_breakpoint |
| 4417 | && thread->prev_pc == breakpoint_pc)) |
| 4418 | regcache_write_pc (regcache, breakpoint_pc); |
| 4419 | } |
| 4420 | } |
| 4421 | |
| 4422 | static bool |
| 4423 | stepped_in_from (struct frame_info *frame, struct frame_id step_frame_id) |
| 4424 | { |
| 4425 | for (frame = get_prev_frame (frame); |
| 4426 | frame != NULL; |
| 4427 | frame = get_prev_frame (frame)) |
| 4428 | { |
| 4429 | if (frame_id_eq (get_frame_id (frame), step_frame_id)) |
| 4430 | return true; |
| 4431 | |
| 4432 | if (get_frame_type (frame) != INLINE_FRAME) |
| 4433 | break; |
| 4434 | } |
| 4435 | |
| 4436 | return false; |
| 4437 | } |
| 4438 | |
| 4439 | /* Look for an inline frame that is marked for skip. |
| 4440 | If PREV_FRAME is TRUE start at the previous frame, |
| 4441 | otherwise start at the current frame. Stop at the |
| 4442 | first non-inline frame, or at the frame where the |
| 4443 | step started. */ |
| 4444 | |
| 4445 | static bool |
| 4446 | inline_frame_is_marked_for_skip (bool prev_frame, struct thread_info *tp) |
| 4447 | { |
| 4448 | struct frame_info *frame = get_current_frame (); |
| 4449 | |
| 4450 | if (prev_frame) |
| 4451 | frame = get_prev_frame (frame); |
| 4452 | |
| 4453 | for (; frame != NULL; frame = get_prev_frame (frame)) |
| 4454 | { |
| 4455 | const char *fn = NULL; |
| 4456 | symtab_and_line sal; |
| 4457 | struct symbol *sym; |
| 4458 | |
| 4459 | if (frame_id_eq (get_frame_id (frame), tp->control.step_frame_id)) |
| 4460 | break; |
| 4461 | if (get_frame_type (frame) != INLINE_FRAME) |
| 4462 | break; |
| 4463 | |
| 4464 | sal = find_frame_sal (frame); |
| 4465 | sym = get_frame_function (frame); |
| 4466 | |
| 4467 | if (sym != NULL) |
| 4468 | fn = sym->print_name (); |
| 4469 | |
| 4470 | if (sal.line != 0 |
| 4471 | && function_name_is_marked_for_skip (fn, sal)) |
| 4472 | return true; |
| 4473 | } |
| 4474 | |
| 4475 | return false; |
| 4476 | } |
| 4477 | |
| 4478 | /* If the event thread has the stop requested flag set, pretend it |
| 4479 | stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to |
| 4480 | target_stop). */ |
| 4481 | |
| 4482 | static bool |
| 4483 | handle_stop_requested (struct execution_control_state *ecs) |
| 4484 | { |
| 4485 | if (ecs->event_thread->stop_requested) |
| 4486 | { |
| 4487 | ecs->ws.kind = TARGET_WAITKIND_STOPPED; |
| 4488 | ecs->ws.value.sig = GDB_SIGNAL_0; |
| 4489 | handle_signal_stop (ecs); |
| 4490 | return true; |
| 4491 | } |
| 4492 | return false; |
| 4493 | } |
| 4494 | |
| 4495 | /* Auxiliary function that handles syscall entry/return events. |
| 4496 | It returns true if the inferior should keep going (and GDB |
| 4497 | should ignore the event), or false if the event deserves to be |
| 4498 | processed. */ |
| 4499 | |
| 4500 | static bool |
| 4501 | handle_syscall_event (struct execution_control_state *ecs) |
| 4502 | { |
| 4503 | struct regcache *regcache; |
| 4504 | int syscall_number; |
| 4505 | |
| 4506 | context_switch (ecs); |
| 4507 | |
| 4508 | regcache = get_thread_regcache (ecs->event_thread); |
| 4509 | syscall_number = ecs->ws.value.syscall_number; |
| 4510 | ecs->event_thread->suspend.stop_pc = regcache_read_pc (regcache); |
| 4511 | |
| 4512 | if (catch_syscall_enabled () > 0 |
| 4513 | && catching_syscall_number (syscall_number) > 0) |
| 4514 | { |
| 4515 | infrun_debug_printf ("syscall number=%d", syscall_number); |
| 4516 | |
| 4517 | ecs->event_thread->control.stop_bpstat |
| 4518 | = bpstat_stop_status (regcache->aspace (), |
| 4519 | ecs->event_thread->suspend.stop_pc, |
| 4520 | ecs->event_thread, &ecs->ws); |
| 4521 | |
| 4522 | if (handle_stop_requested (ecs)) |
| 4523 | return false; |
| 4524 | |
| 4525 | if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat)) |
| 4526 | { |
| 4527 | /* Catchpoint hit. */ |
| 4528 | return false; |
| 4529 | } |
| 4530 | } |
| 4531 | |
| 4532 | if (handle_stop_requested (ecs)) |
| 4533 | return false; |
| 4534 | |
| 4535 | /* If no catchpoint triggered for this, then keep going. */ |
| 4536 | keep_going (ecs); |
| 4537 | |
| 4538 | return true; |
| 4539 | } |
| 4540 | |
| 4541 | /* Lazily fill in the execution_control_state's stop_func_* fields. */ |
| 4542 | |
| 4543 | static void |
| 4544 | fill_in_stop_func (struct gdbarch *gdbarch, |
| 4545 | struct execution_control_state *ecs) |
| 4546 | { |
| 4547 | if (!ecs->stop_func_filled_in) |
| 4548 | { |
| 4549 | const block *block; |
| 4550 | const general_symbol_info *gsi; |
| 4551 | |
| 4552 | /* Don't care about return value; stop_func_start and stop_func_name |
| 4553 | will both be 0 if it doesn't work. */ |
| 4554 | find_pc_partial_function_sym (ecs->event_thread->suspend.stop_pc, |
| 4555 | &gsi, |
| 4556 | &ecs->stop_func_start, |
| 4557 | &ecs->stop_func_end, |
| 4558 | &block); |
| 4559 | ecs->stop_func_name = gsi == nullptr ? nullptr : gsi->print_name (); |
| 4560 | |
| 4561 | /* The call to find_pc_partial_function, above, will set |
| 4562 | stop_func_start and stop_func_end to the start and end |
| 4563 | of the range containing the stop pc. If this range |
| 4564 | contains the entry pc for the block (which is always the |
| 4565 | case for contiguous blocks), advance stop_func_start past |
| 4566 | the function's start offset and entrypoint. Note that |
| 4567 | stop_func_start is NOT advanced when in a range of a |
| 4568 | non-contiguous block that does not contain the entry pc. */ |
| 4569 | if (block != nullptr |
| 4570 | && ecs->stop_func_start <= BLOCK_ENTRY_PC (block) |
| 4571 | && BLOCK_ENTRY_PC (block) < ecs->stop_func_end) |
| 4572 | { |
| 4573 | ecs->stop_func_start |
| 4574 | += gdbarch_deprecated_function_start_offset (gdbarch); |
| 4575 | |
| 4576 | if (gdbarch_skip_entrypoint_p (gdbarch)) |
| 4577 | ecs->stop_func_start |
| 4578 | = gdbarch_skip_entrypoint (gdbarch, ecs->stop_func_start); |
| 4579 | } |
| 4580 | |
| 4581 | ecs->stop_func_filled_in = 1; |
| 4582 | } |
| 4583 | } |
| 4584 | |
| 4585 | |
| 4586 | /* Return the STOP_SOON field of the inferior pointed at by ECS. */ |
| 4587 | |
| 4588 | static enum stop_kind |
| 4589 | get_inferior_stop_soon (execution_control_state *ecs) |
| 4590 | { |
| 4591 | struct inferior *inf = find_inferior_ptid (ecs->target, ecs->ptid); |
| 4592 | |
| 4593 | gdb_assert (inf != NULL); |
| 4594 | return inf->control.stop_soon; |
| 4595 | } |
| 4596 | |
| 4597 | /* Poll for one event out of the current target. Store the resulting |
| 4598 | waitstatus in WS, and return the event ptid. Does not block. */ |
| 4599 | |
| 4600 | static ptid_t |
| 4601 | poll_one_curr_target (struct target_waitstatus *ws) |
| 4602 | { |
| 4603 | ptid_t event_ptid; |
| 4604 | |
| 4605 | overlay_cache_invalid = 1; |
| 4606 | |
| 4607 | /* Flush target cache before starting to handle each event. |
| 4608 | Target was running and cache could be stale. This is just a |
| 4609 | heuristic. Running threads may modify target memory, but we |
| 4610 | don't get any event. */ |
| 4611 | target_dcache_invalidate (); |
| 4612 | |
| 4613 | if (deprecated_target_wait_hook) |
| 4614 | event_ptid = deprecated_target_wait_hook (minus_one_ptid, ws, TARGET_WNOHANG); |
| 4615 | else |
| 4616 | event_ptid = target_wait (minus_one_ptid, ws, TARGET_WNOHANG); |
| 4617 | |
| 4618 | if (debug_infrun) |
| 4619 | print_target_wait_results (minus_one_ptid, event_ptid, ws); |
| 4620 | |
| 4621 | return event_ptid; |
| 4622 | } |
| 4623 | |
| 4624 | /* Wait for one event out of any target. */ |
| 4625 | |
| 4626 | static wait_one_event |
| 4627 | wait_one () |
| 4628 | { |
| 4629 | while (1) |
| 4630 | { |
| 4631 | for (inferior *inf : all_inferiors ()) |
| 4632 | { |
| 4633 | process_stratum_target *target = inf->process_target (); |
| 4634 | if (target == NULL |
| 4635 | || !target->is_async_p () |
| 4636 | || !target->threads_executing) |
| 4637 | continue; |
| 4638 | |
| 4639 | switch_to_inferior_no_thread (inf); |
| 4640 | |
| 4641 | wait_one_event event; |
| 4642 | event.target = target; |
| 4643 | event.ptid = poll_one_curr_target (&event.ws); |
| 4644 | |
| 4645 | if (event.ws.kind == TARGET_WAITKIND_NO_RESUMED) |
| 4646 | { |
| 4647 | /* If nothing is resumed, remove the target from the |
| 4648 | event loop. */ |
| 4649 | target_async (0); |
| 4650 | } |
| 4651 | else if (event.ws.kind != TARGET_WAITKIND_IGNORE) |
| 4652 | return event; |
| 4653 | } |
| 4654 | |
| 4655 | /* Block waiting for some event. */ |
| 4656 | |
| 4657 | fd_set readfds; |
| 4658 | int nfds = 0; |
| 4659 | |
| 4660 | FD_ZERO (&readfds); |
| 4661 | |
| 4662 | for (inferior *inf : all_inferiors ()) |
| 4663 | { |
| 4664 | process_stratum_target *target = inf->process_target (); |
| 4665 | if (target == NULL |
| 4666 | || !target->is_async_p () |
| 4667 | || !target->threads_executing) |
| 4668 | continue; |
| 4669 | |
| 4670 | int fd = target->async_wait_fd (); |
| 4671 | FD_SET (fd, &readfds); |
| 4672 | if (nfds <= fd) |
| 4673 | nfds = fd + 1; |
| 4674 | } |
| 4675 | |
| 4676 | if (nfds == 0) |
| 4677 | { |
| 4678 | /* No waitable targets left. All must be stopped. */ |
| 4679 | return {NULL, minus_one_ptid, {TARGET_WAITKIND_NO_RESUMED}}; |
| 4680 | } |
| 4681 | |
| 4682 | QUIT; |
| 4683 | |
| 4684 | int numfds = interruptible_select (nfds, &readfds, 0, NULL, 0); |
| 4685 | if (numfds < 0) |
| 4686 | { |
| 4687 | if (errno == EINTR) |
| 4688 | continue; |
| 4689 | else |
| 4690 | perror_with_name ("interruptible_select"); |
| 4691 | } |
| 4692 | } |
| 4693 | } |
| 4694 | |
| 4695 | /* Save the thread's event and stop reason to process it later. */ |
| 4696 | |
| 4697 | static void |
| 4698 | save_waitstatus (struct thread_info *tp, const target_waitstatus *ws) |
| 4699 | { |
| 4700 | infrun_debug_printf ("saving status %s for %d.%ld.%ld", |
| 4701 | target_waitstatus_to_string (ws).c_str (), |
| 4702 | tp->ptid.pid (), |
| 4703 | tp->ptid.lwp (), |
| 4704 | tp->ptid.tid ()); |
| 4705 | |
| 4706 | /* Record for later. */ |
| 4707 | tp->suspend.waitstatus = *ws; |
| 4708 | tp->suspend.waitstatus_pending_p = 1; |
| 4709 | |
| 4710 | if (ws->kind == TARGET_WAITKIND_STOPPED |
| 4711 | && ws->value.sig == GDB_SIGNAL_TRAP) |
| 4712 | { |
| 4713 | struct regcache *regcache = get_thread_regcache (tp); |
| 4714 | const address_space *aspace = regcache->aspace (); |
| 4715 | CORE_ADDR pc = regcache_read_pc (regcache); |
| 4716 | |
| 4717 | adjust_pc_after_break (tp, &tp->suspend.waitstatus); |
| 4718 | |
| 4719 | scoped_restore_current_thread restore_thread; |
| 4720 | switch_to_thread (tp); |
| 4721 | |
| 4722 | if (target_stopped_by_watchpoint ()) |
| 4723 | { |
| 4724 | tp->suspend.stop_reason |
| 4725 | = TARGET_STOPPED_BY_WATCHPOINT; |
| 4726 | } |
| 4727 | else if (target_supports_stopped_by_sw_breakpoint () |
| 4728 | && target_stopped_by_sw_breakpoint ()) |
| 4729 | { |
| 4730 | tp->suspend.stop_reason |
| 4731 | = TARGET_STOPPED_BY_SW_BREAKPOINT; |
| 4732 | } |
| 4733 | else if (target_supports_stopped_by_hw_breakpoint () |
| 4734 | && target_stopped_by_hw_breakpoint ()) |
| 4735 | { |
| 4736 | tp->suspend.stop_reason |
| 4737 | = TARGET_STOPPED_BY_HW_BREAKPOINT; |
| 4738 | } |
| 4739 | else if (!target_supports_stopped_by_hw_breakpoint () |
| 4740 | && hardware_breakpoint_inserted_here_p (aspace, |
| 4741 | pc)) |
| 4742 | { |
| 4743 | tp->suspend.stop_reason |
| 4744 | = TARGET_STOPPED_BY_HW_BREAKPOINT; |
| 4745 | } |
| 4746 | else if (!target_supports_stopped_by_sw_breakpoint () |
| 4747 | && software_breakpoint_inserted_here_p (aspace, |
| 4748 | pc)) |
| 4749 | { |
| 4750 | tp->suspend.stop_reason |
| 4751 | = TARGET_STOPPED_BY_SW_BREAKPOINT; |
| 4752 | } |
| 4753 | else if (!thread_has_single_step_breakpoints_set (tp) |
| 4754 | && currently_stepping (tp)) |
| 4755 | { |
| 4756 | tp->suspend.stop_reason |
| 4757 | = TARGET_STOPPED_BY_SINGLE_STEP; |
| 4758 | } |
| 4759 | } |
| 4760 | } |
| 4761 | |
| 4762 | /* Mark the non-executing threads accordingly. In all-stop, all |
| 4763 | threads of all processes are stopped when we get any event |
| 4764 | reported. In non-stop mode, only the event thread stops. */ |
| 4765 | |
| 4766 | static void |
| 4767 | mark_non_executing_threads (process_stratum_target *target, |
| 4768 | ptid_t event_ptid, |
| 4769 | struct target_waitstatus ws) |
| 4770 | { |
| 4771 | ptid_t mark_ptid; |
| 4772 | |
| 4773 | if (!target_is_non_stop_p ()) |
| 4774 | mark_ptid = minus_one_ptid; |
| 4775 | else if (ws.kind == TARGET_WAITKIND_SIGNALLED |
| 4776 | || ws.kind == TARGET_WAITKIND_EXITED) |
| 4777 | { |
| 4778 | /* If we're handling a process exit in non-stop mode, even |
| 4779 | though threads haven't been deleted yet, one would think |
| 4780 | that there is nothing to do, as threads of the dead process |
| 4781 | will be soon deleted, and threads of any other process were |
| 4782 | left running. However, on some targets, threads survive a |
| 4783 | process exit event. E.g., for the "checkpoint" command, |
| 4784 | when the current checkpoint/fork exits, linux-fork.c |
| 4785 | automatically switches to another fork from within |
| 4786 | target_mourn_inferior, by associating the same |
| 4787 | inferior/thread to another fork. We haven't mourned yet at |
| 4788 | this point, but we must mark any threads left in the |
| 4789 | process as not-executing so that finish_thread_state marks |
| 4790 | them stopped (in the user's perspective) if/when we present |
| 4791 | the stop to the user. */ |
| 4792 | mark_ptid = ptid_t (event_ptid.pid ()); |
| 4793 | } |
| 4794 | else |
| 4795 | mark_ptid = event_ptid; |
| 4796 | |
| 4797 | set_executing (target, mark_ptid, false); |
| 4798 | |
| 4799 | /* Likewise the resumed flag. */ |
| 4800 | set_resumed (target, mark_ptid, false); |
| 4801 | } |
| 4802 | |
| 4803 | /* Handle one event after stopping threads. If the eventing thread |
| 4804 | reports back any interesting event, we leave it pending. If the |
| 4805 | eventing thread was in the middle of a displaced step, we |
| 4806 | cancel/finish it, and unless the thread's inferior is being |
| 4807 | detached, put the thread back in the step-over chain. Returns true |
| 4808 | if there are no resumed threads left in the target (thus there's no |
| 4809 | point in waiting further), false otherwise. */ |
| 4810 | |
| 4811 | static bool |
| 4812 | handle_one (const wait_one_event &event) |
| 4813 | { |
| 4814 | infrun_debug_printf |
| 4815 | ("%s %s", target_waitstatus_to_string (&event.ws).c_str (), |
| 4816 | target_pid_to_str (event.ptid).c_str ()); |
| 4817 | |
| 4818 | if (event.ws.kind == TARGET_WAITKIND_NO_RESUMED) |
| 4819 | { |
| 4820 | /* All resumed threads exited. */ |
| 4821 | return true; |
| 4822 | } |
| 4823 | else if (event.ws.kind == TARGET_WAITKIND_THREAD_EXITED |
| 4824 | || event.ws.kind == TARGET_WAITKIND_EXITED |
| 4825 | || event.ws.kind == TARGET_WAITKIND_SIGNALLED) |
| 4826 | { |
| 4827 | /* One thread/process exited/signalled. */ |
| 4828 | |
| 4829 | thread_info *t = nullptr; |
| 4830 | |
| 4831 | /* The target may have reported just a pid. If so, try |
| 4832 | the first non-exited thread. */ |
| 4833 | if (event.ptid.is_pid ()) |
| 4834 | { |
| 4835 | int pid = event.ptid.pid (); |
| 4836 | inferior *inf = find_inferior_pid (event.target, pid); |
| 4837 | for (thread_info *tp : inf->non_exited_threads ()) |
| 4838 | { |
| 4839 | t = tp; |
| 4840 | break; |
| 4841 | } |
| 4842 | |
| 4843 | /* If there is no available thread, the event would |
| 4844 | have to be appended to a per-inferior event list, |
| 4845 | which does not exist (and if it did, we'd have |
| 4846 | to adjust run control command to be able to |
| 4847 | resume such an inferior). We assert here instead |
| 4848 | of going into an infinite loop. */ |
| 4849 | gdb_assert (t != nullptr); |
| 4850 | |
| 4851 | infrun_debug_printf |
| 4852 | ("using %s", target_pid_to_str (t->ptid).c_str ()); |
| 4853 | } |
| 4854 | else |
| 4855 | { |
| 4856 | t = find_thread_ptid (event.target, event.ptid); |
| 4857 | /* Check if this is the first time we see this thread. |
| 4858 | Don't bother adding if it individually exited. */ |
| 4859 | if (t == nullptr |
| 4860 | && event.ws.kind != TARGET_WAITKIND_THREAD_EXITED) |
| 4861 | t = add_thread (event.target, event.ptid); |
| 4862 | } |
| 4863 | |
| 4864 | if (t != nullptr) |
| 4865 | { |
| 4866 | /* Set the threads as non-executing to avoid |
| 4867 | another stop attempt on them. */ |
| 4868 | switch_to_thread_no_regs (t); |
| 4869 | mark_non_executing_threads (event.target, event.ptid, |
| 4870 | event.ws); |
| 4871 | save_waitstatus (t, &event.ws); |
| 4872 | t->stop_requested = false; |
| 4873 | } |
| 4874 | } |
| 4875 | else |
| 4876 | { |
| 4877 | thread_info *t = find_thread_ptid (event.target, event.ptid); |
| 4878 | if (t == NULL) |
| 4879 | t = add_thread (event.target, event.ptid); |
| 4880 | |
| 4881 | t->stop_requested = 0; |
| 4882 | t->executing = 0; |
| 4883 | t->resumed = false; |
| 4884 | t->control.may_range_step = 0; |
| 4885 | |
| 4886 | /* This may be the first time we see the inferior report |
| 4887 | a stop. */ |
| 4888 | inferior *inf = find_inferior_ptid (event.target, event.ptid); |
| 4889 | if (inf->needs_setup) |
| 4890 | { |
| 4891 | switch_to_thread_no_regs (t); |
| 4892 | setup_inferior (0); |
| 4893 | } |
| 4894 | |
| 4895 | if (event.ws.kind == TARGET_WAITKIND_STOPPED |
| 4896 | && event.ws.value.sig == GDB_SIGNAL_0) |
| 4897 | { |
| 4898 | /* We caught the event that we intended to catch, so |
| 4899 | there's no event pending. */ |
| 4900 | t->suspend.waitstatus.kind = TARGET_WAITKIND_IGNORE; |
| 4901 | t->suspend.waitstatus_pending_p = 0; |
| 4902 | |
| 4903 | if (displaced_step_finish (t, GDB_SIGNAL_0) |
| 4904 | == DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED) |
| 4905 | { |
| 4906 | /* Add it back to the step-over queue. */ |
| 4907 | infrun_debug_printf |
| 4908 | ("displaced-step of %s canceled", |
| 4909 | target_pid_to_str (t->ptid).c_str ()); |
| 4910 | |
| 4911 | t->control.trap_expected = 0; |
| 4912 | if (!t->inf->detaching) |
| 4913 | global_thread_step_over_chain_enqueue (t); |
| 4914 | } |
| 4915 | } |
| 4916 | else |
| 4917 | { |
| 4918 | enum gdb_signal sig; |
| 4919 | struct regcache *regcache; |
| 4920 | |
| 4921 | infrun_debug_printf |
| 4922 | ("target_wait %s, saving status for %d.%ld.%ld", |
| 4923 | target_waitstatus_to_string (&event.ws).c_str (), |
| 4924 | t->ptid.pid (), t->ptid.lwp (), t->ptid.tid ()); |
| 4925 | |
| 4926 | /* Record for later. */ |
| 4927 | save_waitstatus (t, &event.ws); |
| 4928 | |
| 4929 | sig = (event.ws.kind == TARGET_WAITKIND_STOPPED |
| 4930 | ? event.ws.value.sig : GDB_SIGNAL_0); |
| 4931 | |
| 4932 | if (displaced_step_finish (t, sig) |
| 4933 | == DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED) |
| 4934 | { |
| 4935 | /* Add it back to the step-over queue. */ |
| 4936 | t->control.trap_expected = 0; |
| 4937 | if (!t->inf->detaching) |
| 4938 | global_thread_step_over_chain_enqueue (t); |
| 4939 | } |
| 4940 | |
| 4941 | regcache = get_thread_regcache (t); |
| 4942 | t->suspend.stop_pc = regcache_read_pc (regcache); |
| 4943 | |
| 4944 | infrun_debug_printf ("saved stop_pc=%s for %s " |
| 4945 | "(currently_stepping=%d)", |
| 4946 | paddress (target_gdbarch (), |
| 4947 | t->suspend.stop_pc), |
| 4948 | target_pid_to_str (t->ptid).c_str (), |
| 4949 | currently_stepping (t)); |
| 4950 | } |
| 4951 | } |
| 4952 | |
| 4953 | return false; |
| 4954 | } |
| 4955 | |
| 4956 | /* See infrun.h. */ |
| 4957 | |
| 4958 | void |
| 4959 | stop_all_threads (void) |
| 4960 | { |
| 4961 | /* We may need multiple passes to discover all threads. */ |
| 4962 | int pass; |
| 4963 | int iterations = 0; |
| 4964 | |
| 4965 | gdb_assert (exists_non_stop_target ()); |
| 4966 | |
| 4967 | infrun_debug_printf ("starting"); |
| 4968 | |
| 4969 | scoped_restore_current_thread restore_thread; |
| 4970 | |
| 4971 | /* Enable thread events of all targets. */ |
| 4972 | for (auto *target : all_non_exited_process_targets ()) |
| 4973 | { |
| 4974 | switch_to_target_no_thread (target); |
| 4975 | target_thread_events (true); |
| 4976 | } |
| 4977 | |
| 4978 | SCOPE_EXIT |
| 4979 | { |
| 4980 | /* Disable thread events of all targets. */ |
| 4981 | for (auto *target : all_non_exited_process_targets ()) |
| 4982 | { |
| 4983 | switch_to_target_no_thread (target); |
| 4984 | target_thread_events (false); |
| 4985 | } |
| 4986 | |
| 4987 | /* Use debug_prefixed_printf directly to get a meaningful function |
| 4988 | name. */ |
| 4989 | if (debug_infrun) |
| 4990 | debug_prefixed_printf ("infrun", "stop_all_threads", "done"); |
| 4991 | }; |
| 4992 | |
| 4993 | /* Request threads to stop, and then wait for the stops. Because |
| 4994 | threads we already know about can spawn more threads while we're |
| 4995 | trying to stop them, and we only learn about new threads when we |
| 4996 | update the thread list, do this in a loop, and keep iterating |
| 4997 | until two passes find no threads that need to be stopped. */ |
| 4998 | for (pass = 0; pass < 2; pass++, iterations++) |
| 4999 | { |
| 5000 | infrun_debug_printf ("pass=%d, iterations=%d", pass, iterations); |
| 5001 | while (1) |
| 5002 | { |
| 5003 | int waits_needed = 0; |
| 5004 | |
| 5005 | for (auto *target : all_non_exited_process_targets ()) |
| 5006 | { |
| 5007 | switch_to_target_no_thread (target); |
| 5008 | update_thread_list (); |
| 5009 | } |
| 5010 | |
| 5011 | /* Go through all threads looking for threads that we need |
| 5012 | to tell the target to stop. */ |
| 5013 | for (thread_info *t : all_non_exited_threads ()) |
| 5014 | { |
| 5015 | /* For a single-target setting with an all-stop target, |
| 5016 | we would not even arrive here. For a multi-target |
| 5017 | setting, until GDB is able to handle a mixture of |
| 5018 | all-stop and non-stop targets, simply skip all-stop |
| 5019 | targets' threads. This should be fine due to the |
| 5020 | protection of 'check_multi_target_resumption'. */ |
| 5021 | |
| 5022 | switch_to_thread_no_regs (t); |
| 5023 | if (!target_is_non_stop_p ()) |
| 5024 | continue; |
| 5025 | |
| 5026 | if (t->executing) |
| 5027 | { |
| 5028 | /* If already stopping, don't request a stop again. |
| 5029 | We just haven't seen the notification yet. */ |
| 5030 | if (!t->stop_requested) |
| 5031 | { |
| 5032 | infrun_debug_printf (" %s executing, need stop", |
| 5033 | target_pid_to_str (t->ptid).c_str ()); |
| 5034 | target_stop (t->ptid); |
| 5035 | t->stop_requested = 1; |
| 5036 | } |
| 5037 | else |
| 5038 | { |
| 5039 | infrun_debug_printf (" %s executing, already stopping", |
| 5040 | target_pid_to_str (t->ptid).c_str ()); |
| 5041 | } |
| 5042 | |
| 5043 | if (t->stop_requested) |
| 5044 | waits_needed++; |
| 5045 | } |
| 5046 | else |
| 5047 | { |
| 5048 | infrun_debug_printf (" %s not executing", |
| 5049 | target_pid_to_str (t->ptid).c_str ()); |
| 5050 | |
| 5051 | /* The thread may be not executing, but still be |
| 5052 | resumed with a pending status to process. */ |
| 5053 | t->resumed = false; |
| 5054 | } |
| 5055 | } |
| 5056 | |
| 5057 | if (waits_needed == 0) |
| 5058 | break; |
| 5059 | |
| 5060 | /* If we find new threads on the second iteration, restart |
| 5061 | over. We want to see two iterations in a row with all |
| 5062 | threads stopped. */ |
| 5063 | if (pass > 0) |
| 5064 | pass = -1; |
| 5065 | |
| 5066 | for (int i = 0; i < waits_needed; i++) |
| 5067 | { |
| 5068 | wait_one_event event = wait_one (); |
| 5069 | if (handle_one (event)) |
| 5070 | break; |
| 5071 | } |
| 5072 | } |
| 5073 | } |
| 5074 | } |
| 5075 | |
| 5076 | /* Handle a TARGET_WAITKIND_NO_RESUMED event. */ |
| 5077 | |
| 5078 | static bool |
| 5079 | handle_no_resumed (struct execution_control_state *ecs) |
| 5080 | { |
| 5081 | if (target_can_async_p ()) |
| 5082 | { |
| 5083 | bool any_sync = false; |
| 5084 | |
| 5085 | for (ui *ui : all_uis ()) |
| 5086 | { |
| 5087 | if (ui->prompt_state == PROMPT_BLOCKED) |
| 5088 | { |
| 5089 | any_sync = true; |
| 5090 | break; |
| 5091 | } |
| 5092 | } |
| 5093 | if (!any_sync) |
| 5094 | { |
| 5095 | /* There were no unwaited-for children left in the target, but, |
| 5096 | we're not synchronously waiting for events either. Just |
| 5097 | ignore. */ |
| 5098 | |
| 5099 | infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED (ignoring: bg)"); |
| 5100 | prepare_to_wait (ecs); |
| 5101 | return true; |
| 5102 | } |
| 5103 | } |
| 5104 | |
| 5105 | /* Otherwise, if we were running a synchronous execution command, we |
| 5106 | may need to cancel it and give the user back the terminal. |
| 5107 | |
| 5108 | In non-stop mode, the target can't tell whether we've already |
| 5109 | consumed previous stop events, so it can end up sending us a |
| 5110 | no-resumed event like so: |
| 5111 | |
| 5112 | #0 - thread 1 is left stopped |
| 5113 | |
| 5114 | #1 - thread 2 is resumed and hits breakpoint |
| 5115 | -> TARGET_WAITKIND_STOPPED |
| 5116 | |
| 5117 | #2 - thread 3 is resumed and exits |
| 5118 | this is the last resumed thread, so |
| 5119 | -> TARGET_WAITKIND_NO_RESUMED |
| 5120 | |
| 5121 | #3 - gdb processes stop for thread 2 and decides to re-resume |
| 5122 | it. |
| 5123 | |
| 5124 | #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event. |
| 5125 | thread 2 is now resumed, so the event should be ignored. |
| 5126 | |
| 5127 | IOW, if the stop for thread 2 doesn't end a foreground command, |
| 5128 | then we need to ignore the following TARGET_WAITKIND_NO_RESUMED |
| 5129 | event. But it could be that the event meant that thread 2 itself |
| 5130 | (or whatever other thread was the last resumed thread) exited. |
| 5131 | |
| 5132 | To address this we refresh the thread list and check whether we |
| 5133 | have resumed threads _now_. In the example above, this removes |
| 5134 | thread 3 from the thread list. If thread 2 was re-resumed, we |
| 5135 | ignore this event. If we find no thread resumed, then we cancel |
| 5136 | the synchronous command and show "no unwaited-for " to the |
| 5137 | user. */ |
| 5138 | |
| 5139 | inferior *curr_inf = current_inferior (); |
| 5140 | |
| 5141 | scoped_restore_current_thread restore_thread; |
| 5142 | |
| 5143 | for (auto *target : all_non_exited_process_targets ()) |
| 5144 | { |
| 5145 | switch_to_target_no_thread (target); |
| 5146 | update_thread_list (); |
| 5147 | } |
| 5148 | |
| 5149 | /* If: |
| 5150 | |
| 5151 | - the current target has no thread executing, and |
| 5152 | - the current inferior is native, and |
| 5153 | - the current inferior is the one which has the terminal, and |
| 5154 | - we did nothing, |
| 5155 | |
| 5156 | then a Ctrl-C from this point on would remain stuck in the |
| 5157 | kernel, until a thread resumes and dequeues it. That would |
| 5158 | result in the GDB CLI not reacting to Ctrl-C, not able to |
| 5159 | interrupt the program. To address this, if the current inferior |
| 5160 | no longer has any thread executing, we give the terminal to some |
| 5161 | other inferior that has at least one thread executing. */ |
| 5162 | bool swap_terminal = true; |
| 5163 | |
| 5164 | /* Whether to ignore this TARGET_WAITKIND_NO_RESUMED event, or |
| 5165 | whether to report it to the user. */ |
| 5166 | bool ignore_event = false; |
| 5167 | |
| 5168 | for (thread_info *thread : all_non_exited_threads ()) |
| 5169 | { |
| 5170 | if (swap_terminal && thread->executing) |
| 5171 | { |
| 5172 | if (thread->inf != curr_inf) |
| 5173 | { |
| 5174 | target_terminal::ours (); |
| 5175 | |
| 5176 | switch_to_thread (thread); |
| 5177 | target_terminal::inferior (); |
| 5178 | } |
| 5179 | swap_terminal = false; |
| 5180 | } |
| 5181 | |
| 5182 | if (!ignore_event |
| 5183 | && (thread->executing |
| 5184 | || thread->suspend.waitstatus_pending_p)) |
| 5185 | { |
| 5186 | /* Either there were no unwaited-for children left in the |
| 5187 | target at some point, but there are now, or some target |
| 5188 | other than the eventing one has unwaited-for children |
| 5189 | left. Just ignore. */ |
| 5190 | infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED " |
| 5191 | "(ignoring: found resumed)"); |
| 5192 | |
| 5193 | ignore_event = true; |
| 5194 | } |
| 5195 | |
| 5196 | if (ignore_event && !swap_terminal) |
| 5197 | break; |
| 5198 | } |
| 5199 | |
| 5200 | if (ignore_event) |
| 5201 | { |
| 5202 | switch_to_inferior_no_thread (curr_inf); |
| 5203 | prepare_to_wait (ecs); |
| 5204 | return true; |
| 5205 | } |
| 5206 | |
| 5207 | /* Go ahead and report the event. */ |
| 5208 | return false; |
| 5209 | } |
| 5210 | |
| 5211 | /* Given an execution control state that has been freshly filled in by |
| 5212 | an event from the inferior, figure out what it means and take |
| 5213 | appropriate action. |
| 5214 | |
| 5215 | The alternatives are: |
| 5216 | |
| 5217 | 1) stop_waiting and return; to really stop and return to the |
| 5218 | debugger. |
| 5219 | |
| 5220 | 2) keep_going and return; to wait for the next event (set |
| 5221 | ecs->event_thread->stepping_over_breakpoint to 1 to single step |
| 5222 | once). */ |
| 5223 | |
| 5224 | static void |
| 5225 | handle_inferior_event (struct execution_control_state *ecs) |
| 5226 | { |
| 5227 | /* Make sure that all temporary struct value objects that were |
| 5228 | created during the handling of the event get deleted at the |
| 5229 | end. */ |
| 5230 | scoped_value_mark free_values; |
| 5231 | |
| 5232 | infrun_debug_printf ("%s", target_waitstatus_to_string (&ecs->ws).c_str ()); |
| 5233 | |
| 5234 | if (ecs->ws.kind == TARGET_WAITKIND_IGNORE) |
| 5235 | { |
| 5236 | /* We had an event in the inferior, but we are not interested in |
| 5237 | handling it at this level. The lower layers have already |
| 5238 | done what needs to be done, if anything. |
| 5239 | |
| 5240 | One of the possible circumstances for this is when the |
| 5241 | inferior produces output for the console. The inferior has |
| 5242 | not stopped, and we are ignoring the event. Another possible |
| 5243 | circumstance is any event which the lower level knows will be |
| 5244 | reported multiple times without an intervening resume. */ |
| 5245 | prepare_to_wait (ecs); |
| 5246 | return; |
| 5247 | } |
| 5248 | |
| 5249 | if (ecs->ws.kind == TARGET_WAITKIND_THREAD_EXITED) |
| 5250 | { |
| 5251 | prepare_to_wait (ecs); |
| 5252 | return; |
| 5253 | } |
| 5254 | |
| 5255 | if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED |
| 5256 | && handle_no_resumed (ecs)) |
| 5257 | return; |
| 5258 | |
| 5259 | /* Cache the last target/ptid/waitstatus. */ |
| 5260 | set_last_target_status (ecs->target, ecs->ptid, ecs->ws); |
| 5261 | |
| 5262 | /* Always clear state belonging to the previous time we stopped. */ |
| 5263 | stop_stack_dummy = STOP_NONE; |
| 5264 | |
| 5265 | if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED) |
| 5266 | { |
| 5267 | /* No unwaited-for children left. IOW, all resumed children |
| 5268 | have exited. */ |
| 5269 | stop_print_frame = false; |
| 5270 | stop_waiting (ecs); |
| 5271 | return; |
| 5272 | } |
| 5273 | |
| 5274 | if (ecs->ws.kind != TARGET_WAITKIND_EXITED |
| 5275 | && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED) |
| 5276 | { |
| 5277 | ecs->event_thread = find_thread_ptid (ecs->target, ecs->ptid); |
| 5278 | /* If it's a new thread, add it to the thread database. */ |
| 5279 | if (ecs->event_thread == NULL) |
| 5280 | ecs->event_thread = add_thread (ecs->target, ecs->ptid); |
| 5281 | |
| 5282 | /* Disable range stepping. If the next step request could use a |
| 5283 | range, this will be end up re-enabled then. */ |
| 5284 | ecs->event_thread->control.may_range_step = 0; |
| 5285 | } |
| 5286 | |
| 5287 | /* Dependent on valid ECS->EVENT_THREAD. */ |
| 5288 | adjust_pc_after_break (ecs->event_thread, &ecs->ws); |
| 5289 | |
| 5290 | /* Dependent on the current PC value modified by adjust_pc_after_break. */ |
| 5291 | reinit_frame_cache (); |
| 5292 | |
| 5293 | breakpoint_retire_moribund (); |
| 5294 | |
| 5295 | /* First, distinguish signals caused by the debugger from signals |
| 5296 | that have to do with the program's own actions. Note that |
| 5297 | breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending |
| 5298 | on the operating system version. Here we detect when a SIGILL or |
| 5299 | SIGEMT is really a breakpoint and change it to SIGTRAP. We do |
| 5300 | something similar for SIGSEGV, since a SIGSEGV will be generated |
| 5301 | when we're trying to execute a breakpoint instruction on a |
| 5302 | non-executable stack. This happens for call dummy breakpoints |
| 5303 | for architectures like SPARC that place call dummies on the |
| 5304 | stack. */ |
| 5305 | if (ecs->ws.kind == TARGET_WAITKIND_STOPPED |
| 5306 | && (ecs->ws.value.sig == GDB_SIGNAL_ILL |
| 5307 | || ecs->ws.value.sig == GDB_SIGNAL_SEGV |
| 5308 | || ecs->ws.value.sig == GDB_SIGNAL_EMT)) |
| 5309 | { |
| 5310 | struct regcache *regcache = get_thread_regcache (ecs->event_thread); |
| 5311 | |
| 5312 | if (breakpoint_inserted_here_p (regcache->aspace (), |
| 5313 | regcache_read_pc (regcache))) |
| 5314 | { |
| 5315 | infrun_debug_printf ("Treating signal as SIGTRAP"); |
| 5316 | ecs->ws.value.sig = GDB_SIGNAL_TRAP; |
| 5317 | } |
| 5318 | } |
| 5319 | |
| 5320 | mark_non_executing_threads (ecs->target, ecs->ptid, ecs->ws); |
| 5321 | |
| 5322 | switch (ecs->ws.kind) |
| 5323 | { |
| 5324 | case TARGET_WAITKIND_LOADED: |
| 5325 | { |
| 5326 | context_switch (ecs); |
| 5327 | /* Ignore gracefully during startup of the inferior, as it might |
| 5328 | be the shell which has just loaded some objects, otherwise |
| 5329 | add the symbols for the newly loaded objects. Also ignore at |
| 5330 | the beginning of an attach or remote session; we will query |
| 5331 | the full list of libraries once the connection is |
| 5332 | established. */ |
| 5333 | |
| 5334 | stop_kind stop_soon = get_inferior_stop_soon (ecs); |
| 5335 | if (stop_soon == NO_STOP_QUIETLY) |
| 5336 | { |
| 5337 | struct regcache *regcache; |
| 5338 | |
| 5339 | regcache = get_thread_regcache (ecs->event_thread); |
| 5340 | |
| 5341 | handle_solib_event (); |
| 5342 | |
| 5343 | ecs->event_thread->control.stop_bpstat |
| 5344 | = bpstat_stop_status (regcache->aspace (), |
| 5345 | ecs->event_thread->suspend.stop_pc, |
| 5346 | ecs->event_thread, &ecs->ws); |
| 5347 | |
| 5348 | if (handle_stop_requested (ecs)) |
| 5349 | return; |
| 5350 | |
| 5351 | if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat)) |
| 5352 | { |
| 5353 | /* A catchpoint triggered. */ |
| 5354 | process_event_stop_test (ecs); |
| 5355 | return; |
| 5356 | } |
| 5357 | |
| 5358 | /* If requested, stop when the dynamic linker notifies |
| 5359 | gdb of events. This allows the user to get control |
| 5360 | and place breakpoints in initializer routines for |
| 5361 | dynamically loaded objects (among other things). */ |
| 5362 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 5363 | if (stop_on_solib_events) |
| 5364 | { |
| 5365 | /* Make sure we print "Stopped due to solib-event" in |
| 5366 | normal_stop. */ |
| 5367 | stop_print_frame = true; |
| 5368 | |
| 5369 | stop_waiting (ecs); |
| 5370 | return; |
| 5371 | } |
| 5372 | } |
| 5373 | |
| 5374 | /* If we are skipping through a shell, or through shared library |
| 5375 | loading that we aren't interested in, resume the program. If |
| 5376 | we're running the program normally, also resume. */ |
| 5377 | if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY) |
| 5378 | { |
| 5379 | /* Loading of shared libraries might have changed breakpoint |
| 5380 | addresses. Make sure new breakpoints are inserted. */ |
| 5381 | if (stop_soon == NO_STOP_QUIETLY) |
| 5382 | insert_breakpoints (); |
| 5383 | resume (GDB_SIGNAL_0); |
| 5384 | prepare_to_wait (ecs); |
| 5385 | return; |
| 5386 | } |
| 5387 | |
| 5388 | /* But stop if we're attaching or setting up a remote |
| 5389 | connection. */ |
| 5390 | if (stop_soon == STOP_QUIETLY_NO_SIGSTOP |
| 5391 | || stop_soon == STOP_QUIETLY_REMOTE) |
| 5392 | { |
| 5393 | infrun_debug_printf ("quietly stopped"); |
| 5394 | stop_waiting (ecs); |
| 5395 | return; |
| 5396 | } |
| 5397 | |
| 5398 | internal_error (__FILE__, __LINE__, |
| 5399 | _("unhandled stop_soon: %d"), (int) stop_soon); |
| 5400 | } |
| 5401 | |
| 5402 | case TARGET_WAITKIND_SPURIOUS: |
| 5403 | if (handle_stop_requested (ecs)) |
| 5404 | return; |
| 5405 | context_switch (ecs); |
| 5406 | resume (GDB_SIGNAL_0); |
| 5407 | prepare_to_wait (ecs); |
| 5408 | return; |
| 5409 | |
| 5410 | case TARGET_WAITKIND_THREAD_CREATED: |
| 5411 | if (handle_stop_requested (ecs)) |
| 5412 | return; |
| 5413 | context_switch (ecs); |
| 5414 | if (!switch_back_to_stepped_thread (ecs)) |
| 5415 | keep_going (ecs); |
| 5416 | return; |
| 5417 | |
| 5418 | case TARGET_WAITKIND_EXITED: |
| 5419 | case TARGET_WAITKIND_SIGNALLED: |
| 5420 | { |
| 5421 | /* Depending on the system, ecs->ptid may point to a thread or |
| 5422 | to a process. On some targets, target_mourn_inferior may |
| 5423 | need to have access to the just-exited thread. That is the |
| 5424 | case of GNU/Linux's "checkpoint" support, for example. |
| 5425 | Call the switch_to_xxx routine as appropriate. */ |
| 5426 | thread_info *thr = find_thread_ptid (ecs->target, ecs->ptid); |
| 5427 | if (thr != nullptr) |
| 5428 | switch_to_thread (thr); |
| 5429 | else |
| 5430 | { |
| 5431 | inferior *inf = find_inferior_ptid (ecs->target, ecs->ptid); |
| 5432 | switch_to_inferior_no_thread (inf); |
| 5433 | } |
| 5434 | } |
| 5435 | handle_vfork_child_exec_or_exit (0); |
| 5436 | target_terminal::ours (); /* Must do this before mourn anyway. */ |
| 5437 | |
| 5438 | /* Clearing any previous state of convenience variables. */ |
| 5439 | clear_exit_convenience_vars (); |
| 5440 | |
| 5441 | if (ecs->ws.kind == TARGET_WAITKIND_EXITED) |
| 5442 | { |
| 5443 | /* Record the exit code in the convenience variable $_exitcode, so |
| 5444 | that the user can inspect this again later. */ |
| 5445 | set_internalvar_integer (lookup_internalvar ("_exitcode"), |
| 5446 | (LONGEST) ecs->ws.value.integer); |
| 5447 | |
| 5448 | /* Also record this in the inferior itself. */ |
| 5449 | current_inferior ()->has_exit_code = 1; |
| 5450 | current_inferior ()->exit_code = (LONGEST) ecs->ws.value.integer; |
| 5451 | |
| 5452 | /* Support the --return-child-result option. */ |
| 5453 | return_child_result_value = ecs->ws.value.integer; |
| 5454 | |
| 5455 | gdb::observers::exited.notify (ecs->ws.value.integer); |
| 5456 | } |
| 5457 | else |
| 5458 | { |
| 5459 | struct gdbarch *gdbarch = current_inferior ()->gdbarch; |
| 5460 | |
| 5461 | if (gdbarch_gdb_signal_to_target_p (gdbarch)) |
| 5462 | { |
| 5463 | /* Set the value of the internal variable $_exitsignal, |
| 5464 | which holds the signal uncaught by the inferior. */ |
| 5465 | set_internalvar_integer (lookup_internalvar ("_exitsignal"), |
| 5466 | gdbarch_gdb_signal_to_target (gdbarch, |
| 5467 | ecs->ws.value.sig)); |
| 5468 | } |
| 5469 | else |
| 5470 | { |
| 5471 | /* We don't have access to the target's method used for |
| 5472 | converting between signal numbers (GDB's internal |
| 5473 | representation <-> target's representation). |
| 5474 | Therefore, we cannot do a good job at displaying this |
| 5475 | information to the user. It's better to just warn |
| 5476 | her about it (if infrun debugging is enabled), and |
| 5477 | give up. */ |
| 5478 | infrun_debug_printf ("Cannot fill $_exitsignal with the correct " |
| 5479 | "signal number."); |
| 5480 | } |
| 5481 | |
| 5482 | gdb::observers::signal_exited.notify (ecs->ws.value.sig); |
| 5483 | } |
| 5484 | |
| 5485 | gdb_flush (gdb_stdout); |
| 5486 | target_mourn_inferior (inferior_ptid); |
| 5487 | stop_print_frame = false; |
| 5488 | stop_waiting (ecs); |
| 5489 | return; |
| 5490 | |
| 5491 | case TARGET_WAITKIND_FORKED: |
| 5492 | case TARGET_WAITKIND_VFORKED: |
| 5493 | /* Check whether the inferior is displaced stepping. */ |
| 5494 | { |
| 5495 | struct regcache *regcache = get_thread_regcache (ecs->event_thread); |
| 5496 | struct gdbarch *gdbarch = regcache->arch (); |
| 5497 | inferior *parent_inf = find_inferior_ptid (ecs->target, ecs->ptid); |
| 5498 | |
| 5499 | /* If this is a fork (child gets its own address space copy) |
| 5500 | and some displaced step buffers were in use at the time of |
| 5501 | the fork, restore the displaced step buffer bytes in the |
| 5502 | child process. |
| 5503 | |
| 5504 | Architectures which support displaced stepping and fork |
| 5505 | events must supply an implementation of |
| 5506 | gdbarch_displaced_step_restore_all_in_ptid. This is not |
| 5507 | enforced during gdbarch validation to support architectures |
| 5508 | which support displaced stepping but not forks. */ |
| 5509 | if (ecs->ws.kind == TARGET_WAITKIND_FORKED |
| 5510 | && gdbarch_supports_displaced_stepping (gdbarch)) |
| 5511 | gdbarch_displaced_step_restore_all_in_ptid |
| 5512 | (gdbarch, parent_inf, ecs->ws.value.related_pid); |
| 5513 | |
| 5514 | /* If displaced stepping is supported, and thread ecs->ptid is |
| 5515 | displaced stepping. */ |
| 5516 | if (displaced_step_in_progress_thread (ecs->event_thread)) |
| 5517 | { |
| 5518 | struct regcache *child_regcache; |
| 5519 | CORE_ADDR parent_pc; |
| 5520 | |
| 5521 | /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED, |
| 5522 | indicating that the displaced stepping of syscall instruction |
| 5523 | has been done. Perform cleanup for parent process here. Note |
| 5524 | that this operation also cleans up the child process for vfork, |
| 5525 | because their pages are shared. */ |
| 5526 | displaced_step_finish (ecs->event_thread, GDB_SIGNAL_TRAP); |
| 5527 | /* Start a new step-over in another thread if there's one |
| 5528 | that needs it. */ |
| 5529 | start_step_over (); |
| 5530 | |
| 5531 | /* Since the vfork/fork syscall instruction was executed in the scratchpad, |
| 5532 | the child's PC is also within the scratchpad. Set the child's PC |
| 5533 | to the parent's PC value, which has already been fixed up. |
| 5534 | FIXME: we use the parent's aspace here, although we're touching |
| 5535 | the child, because the child hasn't been added to the inferior |
| 5536 | list yet at this point. */ |
| 5537 | |
| 5538 | child_regcache |
| 5539 | = get_thread_arch_aspace_regcache (parent_inf->process_target (), |
| 5540 | ecs->ws.value.related_pid, |
| 5541 | gdbarch, |
| 5542 | parent_inf->aspace); |
| 5543 | /* Read PC value of parent process. */ |
| 5544 | parent_pc = regcache_read_pc (regcache); |
| 5545 | |
| 5546 | displaced_debug_printf ("write child pc from %s to %s", |
| 5547 | paddress (gdbarch, |
| 5548 | regcache_read_pc (child_regcache)), |
| 5549 | paddress (gdbarch, parent_pc)); |
| 5550 | |
| 5551 | regcache_write_pc (child_regcache, parent_pc); |
| 5552 | } |
| 5553 | } |
| 5554 | |
| 5555 | context_switch (ecs); |
| 5556 | |
| 5557 | /* Immediately detach breakpoints from the child before there's |
| 5558 | any chance of letting the user delete breakpoints from the |
| 5559 | breakpoint lists. If we don't do this early, it's easy to |
| 5560 | leave left over traps in the child, vis: "break foo; catch |
| 5561 | fork; c; <fork>; del; c; <child calls foo>". We only follow |
| 5562 | the fork on the last `continue', and by that time the |
| 5563 | breakpoint at "foo" is long gone from the breakpoint table. |
| 5564 | If we vforked, then we don't need to unpatch here, since both |
| 5565 | parent and child are sharing the same memory pages; we'll |
| 5566 | need to unpatch at follow/detach time instead to be certain |
| 5567 | that new breakpoints added between catchpoint hit time and |
| 5568 | vfork follow are detached. */ |
| 5569 | if (ecs->ws.kind != TARGET_WAITKIND_VFORKED) |
| 5570 | { |
| 5571 | /* This won't actually modify the breakpoint list, but will |
| 5572 | physically remove the breakpoints from the child. */ |
| 5573 | detach_breakpoints (ecs->ws.value.related_pid); |
| 5574 | } |
| 5575 | |
| 5576 | delete_just_stopped_threads_single_step_breakpoints (); |
| 5577 | |
| 5578 | /* In case the event is caught by a catchpoint, remember that |
| 5579 | the event is to be followed at the next resume of the thread, |
| 5580 | and not immediately. */ |
| 5581 | ecs->event_thread->pending_follow = ecs->ws; |
| 5582 | |
| 5583 | ecs->event_thread->suspend.stop_pc |
| 5584 | = regcache_read_pc (get_thread_regcache (ecs->event_thread)); |
| 5585 | |
| 5586 | ecs->event_thread->control.stop_bpstat |
| 5587 | = bpstat_stop_status (get_current_regcache ()->aspace (), |
| 5588 | ecs->event_thread->suspend.stop_pc, |
| 5589 | ecs->event_thread, &ecs->ws); |
| 5590 | |
| 5591 | if (handle_stop_requested (ecs)) |
| 5592 | return; |
| 5593 | |
| 5594 | /* If no catchpoint triggered for this, then keep going. Note |
| 5595 | that we're interested in knowing the bpstat actually causes a |
| 5596 | stop, not just if it may explain the signal. Software |
| 5597 | watchpoints, for example, always appear in the bpstat. */ |
| 5598 | if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat)) |
| 5599 | { |
| 5600 | bool follow_child |
| 5601 | = (follow_fork_mode_string == follow_fork_mode_child); |
| 5602 | |
| 5603 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 5604 | |
| 5605 | process_stratum_target *targ |
| 5606 | = ecs->event_thread->inf->process_target (); |
| 5607 | |
| 5608 | bool should_resume = follow_fork (); |
| 5609 | |
| 5610 | /* Note that one of these may be an invalid pointer, |
| 5611 | depending on detach_fork. */ |
| 5612 | thread_info *parent = ecs->event_thread; |
| 5613 | thread_info *child |
| 5614 | = find_thread_ptid (targ, ecs->ws.value.related_pid); |
| 5615 | |
| 5616 | /* At this point, the parent is marked running, and the |
| 5617 | child is marked stopped. */ |
| 5618 | |
| 5619 | /* If not resuming the parent, mark it stopped. */ |
| 5620 | if (follow_child && !detach_fork && !non_stop && !sched_multi) |
| 5621 | parent->set_running (false); |
| 5622 | |
| 5623 | /* If resuming the child, mark it running. */ |
| 5624 | if (follow_child || (!detach_fork && (non_stop || sched_multi))) |
| 5625 | child->set_running (true); |
| 5626 | |
| 5627 | /* In non-stop mode, also resume the other branch. */ |
| 5628 | if (!detach_fork && (non_stop |
| 5629 | || (sched_multi && target_is_non_stop_p ()))) |
| 5630 | { |
| 5631 | if (follow_child) |
| 5632 | switch_to_thread (parent); |
| 5633 | else |
| 5634 | switch_to_thread (child); |
| 5635 | |
| 5636 | ecs->event_thread = inferior_thread (); |
| 5637 | ecs->ptid = inferior_ptid; |
| 5638 | keep_going (ecs); |
| 5639 | } |
| 5640 | |
| 5641 | if (follow_child) |
| 5642 | switch_to_thread (child); |
| 5643 | else |
| 5644 | switch_to_thread (parent); |
| 5645 | |
| 5646 | ecs->event_thread = inferior_thread (); |
| 5647 | ecs->ptid = inferior_ptid; |
| 5648 | |
| 5649 | if (should_resume) |
| 5650 | keep_going (ecs); |
| 5651 | else |
| 5652 | stop_waiting (ecs); |
| 5653 | return; |
| 5654 | } |
| 5655 | process_event_stop_test (ecs); |
| 5656 | return; |
| 5657 | |
| 5658 | case TARGET_WAITKIND_VFORK_DONE: |
| 5659 | /* Done with the shared memory region. Re-insert breakpoints in |
| 5660 | the parent, and keep going. */ |
| 5661 | |
| 5662 | context_switch (ecs); |
| 5663 | |
| 5664 | current_inferior ()->waiting_for_vfork_done = 0; |
| 5665 | current_inferior ()->pspace->breakpoints_not_allowed = 0; |
| 5666 | |
| 5667 | if (handle_stop_requested (ecs)) |
| 5668 | return; |
| 5669 | |
| 5670 | /* This also takes care of reinserting breakpoints in the |
| 5671 | previously locked inferior. */ |
| 5672 | keep_going (ecs); |
| 5673 | return; |
| 5674 | |
| 5675 | case TARGET_WAITKIND_EXECD: |
| 5676 | |
| 5677 | /* Note we can't read registers yet (the stop_pc), because we |
| 5678 | don't yet know the inferior's post-exec architecture. |
| 5679 | 'stop_pc' is explicitly read below instead. */ |
| 5680 | switch_to_thread_no_regs (ecs->event_thread); |
| 5681 | |
| 5682 | /* Do whatever is necessary to the parent branch of the vfork. */ |
| 5683 | handle_vfork_child_exec_or_exit (1); |
| 5684 | |
| 5685 | /* This causes the eventpoints and symbol table to be reset. |
| 5686 | Must do this now, before trying to determine whether to |
| 5687 | stop. */ |
| 5688 | follow_exec (inferior_ptid, ecs->ws.value.execd_pathname); |
| 5689 | |
| 5690 | /* In follow_exec we may have deleted the original thread and |
| 5691 | created a new one. Make sure that the event thread is the |
| 5692 | execd thread for that case (this is a nop otherwise). */ |
| 5693 | ecs->event_thread = inferior_thread (); |
| 5694 | |
| 5695 | ecs->event_thread->suspend.stop_pc |
| 5696 | = regcache_read_pc (get_thread_regcache (ecs->event_thread)); |
| 5697 | |
| 5698 | ecs->event_thread->control.stop_bpstat |
| 5699 | = bpstat_stop_status (get_current_regcache ()->aspace (), |
| 5700 | ecs->event_thread->suspend.stop_pc, |
| 5701 | ecs->event_thread, &ecs->ws); |
| 5702 | |
| 5703 | /* Note that this may be referenced from inside |
| 5704 | bpstat_stop_status above, through inferior_has_execd. */ |
| 5705 | xfree (ecs->ws.value.execd_pathname); |
| 5706 | ecs->ws.value.execd_pathname = NULL; |
| 5707 | |
| 5708 | if (handle_stop_requested (ecs)) |
| 5709 | return; |
| 5710 | |
| 5711 | /* If no catchpoint triggered for this, then keep going. */ |
| 5712 | if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat)) |
| 5713 | { |
| 5714 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 5715 | keep_going (ecs); |
| 5716 | return; |
| 5717 | } |
| 5718 | process_event_stop_test (ecs); |
| 5719 | return; |
| 5720 | |
| 5721 | /* Be careful not to try to gather much state about a thread |
| 5722 | that's in a syscall. It's frequently a losing proposition. */ |
| 5723 | case TARGET_WAITKIND_SYSCALL_ENTRY: |
| 5724 | /* Getting the current syscall number. */ |
| 5725 | if (handle_syscall_event (ecs) == 0) |
| 5726 | process_event_stop_test (ecs); |
| 5727 | return; |
| 5728 | |
| 5729 | /* Before examining the threads further, step this thread to |
| 5730 | get it entirely out of the syscall. (We get notice of the |
| 5731 | event when the thread is just on the verge of exiting a |
| 5732 | syscall. Stepping one instruction seems to get it back |
| 5733 | into user code.) */ |
| 5734 | case TARGET_WAITKIND_SYSCALL_RETURN: |
| 5735 | if (handle_syscall_event (ecs) == 0) |
| 5736 | process_event_stop_test (ecs); |
| 5737 | return; |
| 5738 | |
| 5739 | case TARGET_WAITKIND_STOPPED: |
| 5740 | handle_signal_stop (ecs); |
| 5741 | return; |
| 5742 | |
| 5743 | case TARGET_WAITKIND_NO_HISTORY: |
| 5744 | /* Reverse execution: target ran out of history info. */ |
| 5745 | |
| 5746 | /* Switch to the stopped thread. */ |
| 5747 | context_switch (ecs); |
| 5748 | infrun_debug_printf ("stopped"); |
| 5749 | |
| 5750 | delete_just_stopped_threads_single_step_breakpoints (); |
| 5751 | ecs->event_thread->suspend.stop_pc |
| 5752 | = regcache_read_pc (get_thread_regcache (inferior_thread ())); |
| 5753 | |
| 5754 | if (handle_stop_requested (ecs)) |
| 5755 | return; |
| 5756 | |
| 5757 | gdb::observers::no_history.notify (); |
| 5758 | stop_waiting (ecs); |
| 5759 | return; |
| 5760 | } |
| 5761 | } |
| 5762 | |
| 5763 | /* Restart threads back to what they were trying to do back when we |
| 5764 | paused them for an in-line step-over. The EVENT_THREAD thread is |
| 5765 | ignored. */ |
| 5766 | |
| 5767 | static void |
| 5768 | restart_threads (struct thread_info *event_thread) |
| 5769 | { |
| 5770 | /* In case the instruction just stepped spawned a new thread. */ |
| 5771 | update_thread_list (); |
| 5772 | |
| 5773 | for (thread_info *tp : all_non_exited_threads ()) |
| 5774 | { |
| 5775 | if (tp->inf->detaching) |
| 5776 | { |
| 5777 | infrun_debug_printf ("restart threads: [%s] inferior detaching", |
| 5778 | target_pid_to_str (tp->ptid).c_str ()); |
| 5779 | continue; |
| 5780 | } |
| 5781 | |
| 5782 | switch_to_thread_no_regs (tp); |
| 5783 | |
| 5784 | if (tp == event_thread) |
| 5785 | { |
| 5786 | infrun_debug_printf ("restart threads: [%s] is event thread", |
| 5787 | target_pid_to_str (tp->ptid).c_str ()); |
| 5788 | continue; |
| 5789 | } |
| 5790 | |
| 5791 | if (!(tp->state == THREAD_RUNNING || tp->control.in_infcall)) |
| 5792 | { |
| 5793 | infrun_debug_printf ("restart threads: [%s] not meant to be running", |
| 5794 | target_pid_to_str (tp->ptid).c_str ()); |
| 5795 | continue; |
| 5796 | } |
| 5797 | |
| 5798 | if (tp->resumed) |
| 5799 | { |
| 5800 | infrun_debug_printf ("restart threads: [%s] resumed", |
| 5801 | target_pid_to_str (tp->ptid).c_str ()); |
| 5802 | gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p); |
| 5803 | continue; |
| 5804 | } |
| 5805 | |
| 5806 | if (thread_is_in_step_over_chain (tp)) |
| 5807 | { |
| 5808 | infrun_debug_printf ("restart threads: [%s] needs step-over", |
| 5809 | target_pid_to_str (tp->ptid).c_str ()); |
| 5810 | gdb_assert (!tp->resumed); |
| 5811 | continue; |
| 5812 | } |
| 5813 | |
| 5814 | |
| 5815 | if (tp->suspend.waitstatus_pending_p) |
| 5816 | { |
| 5817 | infrun_debug_printf ("restart threads: [%s] has pending status", |
| 5818 | target_pid_to_str (tp->ptid).c_str ()); |
| 5819 | tp->resumed = true; |
| 5820 | continue; |
| 5821 | } |
| 5822 | |
| 5823 | gdb_assert (!tp->stop_requested); |
| 5824 | |
| 5825 | /* If some thread needs to start a step-over at this point, it |
| 5826 | should still be in the step-over queue, and thus skipped |
| 5827 | above. */ |
| 5828 | if (thread_still_needs_step_over (tp)) |
| 5829 | { |
| 5830 | internal_error (__FILE__, __LINE__, |
| 5831 | "thread [%s] needs a step-over, but not in " |
| 5832 | "step-over queue\n", |
| 5833 | target_pid_to_str (tp->ptid).c_str ()); |
| 5834 | } |
| 5835 | |
| 5836 | if (currently_stepping (tp)) |
| 5837 | { |
| 5838 | infrun_debug_printf ("restart threads: [%s] was stepping", |
| 5839 | target_pid_to_str (tp->ptid).c_str ()); |
| 5840 | keep_going_stepped_thread (tp); |
| 5841 | } |
| 5842 | else |
| 5843 | { |
| 5844 | struct execution_control_state ecss; |
| 5845 | struct execution_control_state *ecs = &ecss; |
| 5846 | |
| 5847 | infrun_debug_printf ("restart threads: [%s] continuing", |
| 5848 | target_pid_to_str (tp->ptid).c_str ()); |
| 5849 | reset_ecs (ecs, tp); |
| 5850 | switch_to_thread (tp); |
| 5851 | keep_going_pass_signal (ecs); |
| 5852 | } |
| 5853 | } |
| 5854 | } |
| 5855 | |
| 5856 | /* Callback for iterate_over_threads. Find a resumed thread that has |
| 5857 | a pending waitstatus. */ |
| 5858 | |
| 5859 | static int |
| 5860 | resumed_thread_with_pending_status (struct thread_info *tp, |
| 5861 | void *arg) |
| 5862 | { |
| 5863 | return (tp->resumed |
| 5864 | && tp->suspend.waitstatus_pending_p); |
| 5865 | } |
| 5866 | |
| 5867 | /* Called when we get an event that may finish an in-line or |
| 5868 | out-of-line (displaced stepping) step-over started previously. |
| 5869 | Return true if the event is processed and we should go back to the |
| 5870 | event loop; false if the caller should continue processing the |
| 5871 | event. */ |
| 5872 | |
| 5873 | static int |
| 5874 | finish_step_over (struct execution_control_state *ecs) |
| 5875 | { |
| 5876 | displaced_step_finish (ecs->event_thread, |
| 5877 | ecs->event_thread->suspend.stop_signal); |
| 5878 | |
| 5879 | bool had_step_over_info = step_over_info_valid_p (); |
| 5880 | |
| 5881 | if (had_step_over_info) |
| 5882 | { |
| 5883 | /* If we're stepping over a breakpoint with all threads locked, |
| 5884 | then only the thread that was stepped should be reporting |
| 5885 | back an event. */ |
| 5886 | gdb_assert (ecs->event_thread->control.trap_expected); |
| 5887 | |
| 5888 | clear_step_over_info (); |
| 5889 | } |
| 5890 | |
| 5891 | if (!target_is_non_stop_p ()) |
| 5892 | return 0; |
| 5893 | |
| 5894 | /* Start a new step-over in another thread if there's one that |
| 5895 | needs it. */ |
| 5896 | start_step_over (); |
| 5897 | |
| 5898 | /* If we were stepping over a breakpoint before, and haven't started |
| 5899 | a new in-line step-over sequence, then restart all other threads |
| 5900 | (except the event thread). We can't do this in all-stop, as then |
| 5901 | e.g., we wouldn't be able to issue any other remote packet until |
| 5902 | these other threads stop. */ |
| 5903 | if (had_step_over_info && !step_over_info_valid_p ()) |
| 5904 | { |
| 5905 | struct thread_info *pending; |
| 5906 | |
| 5907 | /* If we only have threads with pending statuses, the restart |
| 5908 | below won't restart any thread and so nothing re-inserts the |
| 5909 | breakpoint we just stepped over. But we need it inserted |
| 5910 | when we later process the pending events, otherwise if |
| 5911 | another thread has a pending event for this breakpoint too, |
| 5912 | we'd discard its event (because the breakpoint that |
| 5913 | originally caused the event was no longer inserted). */ |
| 5914 | context_switch (ecs); |
| 5915 | insert_breakpoints (); |
| 5916 | |
| 5917 | restart_threads (ecs->event_thread); |
| 5918 | |
| 5919 | /* If we have events pending, go through handle_inferior_event |
| 5920 | again, picking up a pending event at random. This avoids |
| 5921 | thread starvation. */ |
| 5922 | |
| 5923 | /* But not if we just stepped over a watchpoint in order to let |
| 5924 | the instruction execute so we can evaluate its expression. |
| 5925 | The set of watchpoints that triggered is recorded in the |
| 5926 | breakpoint objects themselves (see bp->watchpoint_triggered). |
| 5927 | If we processed another event first, that other event could |
| 5928 | clobber this info. */ |
| 5929 | if (ecs->event_thread->stepping_over_watchpoint) |
| 5930 | return 0; |
| 5931 | |
| 5932 | pending = iterate_over_threads (resumed_thread_with_pending_status, |
| 5933 | NULL); |
| 5934 | if (pending != NULL) |
| 5935 | { |
| 5936 | struct thread_info *tp = ecs->event_thread; |
| 5937 | struct regcache *regcache; |
| 5938 | |
| 5939 | infrun_debug_printf ("found resumed threads with " |
| 5940 | "pending events, saving status"); |
| 5941 | |
| 5942 | gdb_assert (pending != tp); |
| 5943 | |
| 5944 | /* Record the event thread's event for later. */ |
| 5945 | save_waitstatus (tp, &ecs->ws); |
| 5946 | /* This was cleared early, by handle_inferior_event. Set it |
| 5947 | so this pending event is considered by |
| 5948 | do_target_wait. */ |
| 5949 | tp->resumed = true; |
| 5950 | |
| 5951 | gdb_assert (!tp->executing); |
| 5952 | |
| 5953 | regcache = get_thread_regcache (tp); |
| 5954 | tp->suspend.stop_pc = regcache_read_pc (regcache); |
| 5955 | |
| 5956 | infrun_debug_printf ("saved stop_pc=%s for %s " |
| 5957 | "(currently_stepping=%d)", |
| 5958 | paddress (target_gdbarch (), |
| 5959 | tp->suspend.stop_pc), |
| 5960 | target_pid_to_str (tp->ptid).c_str (), |
| 5961 | currently_stepping (tp)); |
| 5962 | |
| 5963 | /* This in-line step-over finished; clear this so we won't |
| 5964 | start a new one. This is what handle_signal_stop would |
| 5965 | do, if we returned false. */ |
| 5966 | tp->stepping_over_breakpoint = 0; |
| 5967 | |
| 5968 | /* Wake up the event loop again. */ |
| 5969 | mark_async_event_handler (infrun_async_inferior_event_token); |
| 5970 | |
| 5971 | prepare_to_wait (ecs); |
| 5972 | return 1; |
| 5973 | } |
| 5974 | } |
| 5975 | |
| 5976 | return 0; |
| 5977 | } |
| 5978 | |
| 5979 | /* Come here when the program has stopped with a signal. */ |
| 5980 | |
| 5981 | static void |
| 5982 | handle_signal_stop (struct execution_control_state *ecs) |
| 5983 | { |
| 5984 | struct frame_info *frame; |
| 5985 | struct gdbarch *gdbarch; |
| 5986 | int stopped_by_watchpoint; |
| 5987 | enum stop_kind stop_soon; |
| 5988 | int random_signal; |
| 5989 | |
| 5990 | gdb_assert (ecs->ws.kind == TARGET_WAITKIND_STOPPED); |
| 5991 | |
| 5992 | ecs->event_thread->suspend.stop_signal = ecs->ws.value.sig; |
| 5993 | |
| 5994 | /* Do we need to clean up the state of a thread that has |
| 5995 | completed a displaced single-step? (Doing so usually affects |
| 5996 | the PC, so do it here, before we set stop_pc.) */ |
| 5997 | if (finish_step_over (ecs)) |
| 5998 | return; |
| 5999 | |
| 6000 | /* If we either finished a single-step or hit a breakpoint, but |
| 6001 | the user wanted this thread to be stopped, pretend we got a |
| 6002 | SIG0 (generic unsignaled stop). */ |
| 6003 | if (ecs->event_thread->stop_requested |
| 6004 | && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP) |
| 6005 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 6006 | |
| 6007 | ecs->event_thread->suspend.stop_pc |
| 6008 | = regcache_read_pc (get_thread_regcache (ecs->event_thread)); |
| 6009 | |
| 6010 | context_switch (ecs); |
| 6011 | |
| 6012 | if (deprecated_context_hook) |
| 6013 | deprecated_context_hook (ecs->event_thread->global_num); |
| 6014 | |
| 6015 | if (debug_infrun) |
| 6016 | { |
| 6017 | struct regcache *regcache = get_thread_regcache (ecs->event_thread); |
| 6018 | struct gdbarch *reg_gdbarch = regcache->arch (); |
| 6019 | |
| 6020 | infrun_debug_printf ("stop_pc=%s", |
| 6021 | paddress (reg_gdbarch, |
| 6022 | ecs->event_thread->suspend.stop_pc)); |
| 6023 | if (target_stopped_by_watchpoint ()) |
| 6024 | { |
| 6025 | CORE_ADDR addr; |
| 6026 | |
| 6027 | infrun_debug_printf ("stopped by watchpoint"); |
| 6028 | |
| 6029 | if (target_stopped_data_address (current_inferior ()->top_target (), |
| 6030 | &addr)) |
| 6031 | infrun_debug_printf ("stopped data address=%s", |
| 6032 | paddress (reg_gdbarch, addr)); |
| 6033 | else |
| 6034 | infrun_debug_printf ("(no data address available)"); |
| 6035 | } |
| 6036 | } |
| 6037 | |
| 6038 | /* This is originated from start_remote(), start_inferior() and |
| 6039 | shared libraries hook functions. */ |
| 6040 | stop_soon = get_inferior_stop_soon (ecs); |
| 6041 | if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE) |
| 6042 | { |
| 6043 | infrun_debug_printf ("quietly stopped"); |
| 6044 | stop_print_frame = true; |
| 6045 | stop_waiting (ecs); |
| 6046 | return; |
| 6047 | } |
| 6048 | |
| 6049 | /* This originates from attach_command(). We need to overwrite |
| 6050 | the stop_signal here, because some kernels don't ignore a |
| 6051 | SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call. |
| 6052 | See more comments in inferior.h. On the other hand, if we |
| 6053 | get a non-SIGSTOP, report it to the user - assume the backend |
| 6054 | will handle the SIGSTOP if it should show up later. |
| 6055 | |
| 6056 | Also consider that the attach is complete when we see a |
| 6057 | SIGTRAP. Some systems (e.g. Windows), and stubs supporting |
| 6058 | target extended-remote report it instead of a SIGSTOP |
| 6059 | (e.g. gdbserver). We already rely on SIGTRAP being our |
| 6060 | signal, so this is no exception. |
| 6061 | |
| 6062 | Also consider that the attach is complete when we see a |
| 6063 | GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell |
| 6064 | the target to stop all threads of the inferior, in case the |
| 6065 | low level attach operation doesn't stop them implicitly. If |
| 6066 | they weren't stopped implicitly, then the stub will report a |
| 6067 | GDB_SIGNAL_0, meaning: stopped for no particular reason |
| 6068 | other than GDB's request. */ |
| 6069 | if (stop_soon == STOP_QUIETLY_NO_SIGSTOP |
| 6070 | && (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_STOP |
| 6071 | || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP |
| 6072 | || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_0)) |
| 6073 | { |
| 6074 | stop_print_frame = true; |
| 6075 | stop_waiting (ecs); |
| 6076 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 6077 | return; |
| 6078 | } |
| 6079 | |
| 6080 | /* At this point, get hold of the now-current thread's frame. */ |
| 6081 | frame = get_current_frame (); |
| 6082 | gdbarch = get_frame_arch (frame); |
| 6083 | |
| 6084 | /* Pull the single step breakpoints out of the target. */ |
| 6085 | if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP) |
| 6086 | { |
| 6087 | struct regcache *regcache; |
| 6088 | CORE_ADDR pc; |
| 6089 | |
| 6090 | regcache = get_thread_regcache (ecs->event_thread); |
| 6091 | const address_space *aspace = regcache->aspace (); |
| 6092 | |
| 6093 | pc = regcache_read_pc (regcache); |
| 6094 | |
| 6095 | /* However, before doing so, if this single-step breakpoint was |
| 6096 | actually for another thread, set this thread up for moving |
| 6097 | past it. */ |
| 6098 | if (!thread_has_single_step_breakpoint_here (ecs->event_thread, |
| 6099 | aspace, pc)) |
| 6100 | { |
| 6101 | if (single_step_breakpoint_inserted_here_p (aspace, pc)) |
| 6102 | { |
| 6103 | infrun_debug_printf ("[%s] hit another thread's single-step " |
| 6104 | "breakpoint", |
| 6105 | target_pid_to_str (ecs->ptid).c_str ()); |
| 6106 | ecs->hit_singlestep_breakpoint = 1; |
| 6107 | } |
| 6108 | } |
| 6109 | else |
| 6110 | { |
| 6111 | infrun_debug_printf ("[%s] hit its single-step breakpoint", |
| 6112 | target_pid_to_str (ecs->ptid).c_str ()); |
| 6113 | } |
| 6114 | } |
| 6115 | delete_just_stopped_threads_single_step_breakpoints (); |
| 6116 | |
| 6117 | if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP |
| 6118 | && ecs->event_thread->control.trap_expected |
| 6119 | && ecs->event_thread->stepping_over_watchpoint) |
| 6120 | stopped_by_watchpoint = 0; |
| 6121 | else |
| 6122 | stopped_by_watchpoint = watchpoints_triggered (&ecs->ws); |
| 6123 | |
| 6124 | /* If necessary, step over this watchpoint. We'll be back to display |
| 6125 | it in a moment. */ |
| 6126 | if (stopped_by_watchpoint |
| 6127 | && (target_have_steppable_watchpoint () |
| 6128 | || gdbarch_have_nonsteppable_watchpoint (gdbarch))) |
| 6129 | { |
| 6130 | /* At this point, we are stopped at an instruction which has |
| 6131 | attempted to write to a piece of memory under control of |
| 6132 | a watchpoint. The instruction hasn't actually executed |
| 6133 | yet. If we were to evaluate the watchpoint expression |
| 6134 | now, we would get the old value, and therefore no change |
| 6135 | would seem to have occurred. |
| 6136 | |
| 6137 | In order to make watchpoints work `right', we really need |
| 6138 | to complete the memory write, and then evaluate the |
| 6139 | watchpoint expression. We do this by single-stepping the |
| 6140 | target. |
| 6141 | |
| 6142 | It may not be necessary to disable the watchpoint to step over |
| 6143 | it. For example, the PA can (with some kernel cooperation) |
| 6144 | single step over a watchpoint without disabling the watchpoint. |
| 6145 | |
| 6146 | It is far more common to need to disable a watchpoint to step |
| 6147 | the inferior over it. If we have non-steppable watchpoints, |
| 6148 | we must disable the current watchpoint; it's simplest to |
| 6149 | disable all watchpoints. |
| 6150 | |
| 6151 | Any breakpoint at PC must also be stepped over -- if there's |
| 6152 | one, it will have already triggered before the watchpoint |
| 6153 | triggered, and we either already reported it to the user, or |
| 6154 | it didn't cause a stop and we called keep_going. In either |
| 6155 | case, if there was a breakpoint at PC, we must be trying to |
| 6156 | step past it. */ |
| 6157 | ecs->event_thread->stepping_over_watchpoint = 1; |
| 6158 | keep_going (ecs); |
| 6159 | return; |
| 6160 | } |
| 6161 | |
| 6162 | ecs->event_thread->stepping_over_breakpoint = 0; |
| 6163 | ecs->event_thread->stepping_over_watchpoint = 0; |
| 6164 | bpstat_clear (&ecs->event_thread->control.stop_bpstat); |
| 6165 | ecs->event_thread->control.stop_step = 0; |
| 6166 | stop_print_frame = true; |
| 6167 | stopped_by_random_signal = 0; |
| 6168 | bpstat stop_chain = NULL; |
| 6169 | |
| 6170 | /* Hide inlined functions starting here, unless we just performed stepi or |
| 6171 | nexti. After stepi and nexti, always show the innermost frame (not any |
| 6172 | inline function call sites). */ |
| 6173 | if (ecs->event_thread->control.step_range_end != 1) |
| 6174 | { |
| 6175 | const address_space *aspace |
| 6176 | = get_thread_regcache (ecs->event_thread)->aspace (); |
| 6177 | |
| 6178 | /* skip_inline_frames is expensive, so we avoid it if we can |
| 6179 | determine that the address is one where functions cannot have |
| 6180 | been inlined. This improves performance with inferiors that |
| 6181 | load a lot of shared libraries, because the solib event |
| 6182 | breakpoint is defined as the address of a function (i.e. not |
| 6183 | inline). Note that we have to check the previous PC as well |
| 6184 | as the current one to catch cases when we have just |
| 6185 | single-stepped off a breakpoint prior to reinstating it. |
| 6186 | Note that we're assuming that the code we single-step to is |
| 6187 | not inline, but that's not definitive: there's nothing |
| 6188 | preventing the event breakpoint function from containing |
| 6189 | inlined code, and the single-step ending up there. If the |
| 6190 | user had set a breakpoint on that inlined code, the missing |
| 6191 | skip_inline_frames call would break things. Fortunately |
| 6192 | that's an extremely unlikely scenario. */ |
| 6193 | if (!pc_at_non_inline_function (aspace, |
| 6194 | ecs->event_thread->suspend.stop_pc, |
| 6195 | &ecs->ws) |
| 6196 | && !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP |
| 6197 | && ecs->event_thread->control.trap_expected |
| 6198 | && pc_at_non_inline_function (aspace, |
| 6199 | ecs->event_thread->prev_pc, |
| 6200 | &ecs->ws))) |
| 6201 | { |
| 6202 | stop_chain = build_bpstat_chain (aspace, |
| 6203 | ecs->event_thread->suspend.stop_pc, |
| 6204 | &ecs->ws); |
| 6205 | skip_inline_frames (ecs->event_thread, stop_chain); |
| 6206 | |
| 6207 | /* Re-fetch current thread's frame in case that invalidated |
| 6208 | the frame cache. */ |
| 6209 | frame = get_current_frame (); |
| 6210 | gdbarch = get_frame_arch (frame); |
| 6211 | } |
| 6212 | } |
| 6213 | |
| 6214 | if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP |
| 6215 | && ecs->event_thread->control.trap_expected |
| 6216 | && gdbarch_single_step_through_delay_p (gdbarch) |
| 6217 | && currently_stepping (ecs->event_thread)) |
| 6218 | { |
| 6219 | /* We're trying to step off a breakpoint. Turns out that we're |
| 6220 | also on an instruction that needs to be stepped multiple |
| 6221 | times before it's been fully executing. E.g., architectures |
| 6222 | with a delay slot. It needs to be stepped twice, once for |
| 6223 | the instruction and once for the delay slot. */ |
| 6224 | int step_through_delay |
| 6225 | = gdbarch_single_step_through_delay (gdbarch, frame); |
| 6226 | |
| 6227 | if (step_through_delay) |
| 6228 | infrun_debug_printf ("step through delay"); |
| 6229 | |
| 6230 | if (ecs->event_thread->control.step_range_end == 0 |
| 6231 | && step_through_delay) |
| 6232 | { |
| 6233 | /* The user issued a continue when stopped at a breakpoint. |
| 6234 | Set up for another trap and get out of here. */ |
| 6235 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6236 | keep_going (ecs); |
| 6237 | return; |
| 6238 | } |
| 6239 | else if (step_through_delay) |
| 6240 | { |
| 6241 | /* The user issued a step when stopped at a breakpoint. |
| 6242 | Maybe we should stop, maybe we should not - the delay |
| 6243 | slot *might* correspond to a line of source. In any |
| 6244 | case, don't decide that here, just set |
| 6245 | ecs->stepping_over_breakpoint, making sure we |
| 6246 | single-step again before breakpoints are re-inserted. */ |
| 6247 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6248 | } |
| 6249 | } |
| 6250 | |
| 6251 | /* See if there is a breakpoint/watchpoint/catchpoint/etc. that |
| 6252 | handles this event. */ |
| 6253 | ecs->event_thread->control.stop_bpstat |
| 6254 | = bpstat_stop_status (get_current_regcache ()->aspace (), |
| 6255 | ecs->event_thread->suspend.stop_pc, |
| 6256 | ecs->event_thread, &ecs->ws, stop_chain); |
| 6257 | |
| 6258 | /* Following in case break condition called a |
| 6259 | function. */ |
| 6260 | stop_print_frame = true; |
| 6261 | |
| 6262 | /* This is where we handle "moribund" watchpoints. Unlike |
| 6263 | software breakpoints traps, hardware watchpoint traps are |
| 6264 | always distinguishable from random traps. If no high-level |
| 6265 | watchpoint is associated with the reported stop data address |
| 6266 | anymore, then the bpstat does not explain the signal --- |
| 6267 | simply make sure to ignore it if `stopped_by_watchpoint' is |
| 6268 | set. */ |
| 6269 | |
| 6270 | if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP |
| 6271 | && !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat, |
| 6272 | GDB_SIGNAL_TRAP) |
| 6273 | && stopped_by_watchpoint) |
| 6274 | { |
| 6275 | infrun_debug_printf ("no user watchpoint explains watchpoint SIGTRAP, " |
| 6276 | "ignoring"); |
| 6277 | } |
| 6278 | |
| 6279 | /* NOTE: cagney/2003-03-29: These checks for a random signal |
| 6280 | at one stage in the past included checks for an inferior |
| 6281 | function call's call dummy's return breakpoint. The original |
| 6282 | comment, that went with the test, read: |
| 6283 | |
| 6284 | ``End of a stack dummy. Some systems (e.g. Sony news) give |
| 6285 | another signal besides SIGTRAP, so check here as well as |
| 6286 | above.'' |
| 6287 | |
| 6288 | If someone ever tries to get call dummys on a |
| 6289 | non-executable stack to work (where the target would stop |
| 6290 | with something like a SIGSEGV), then those tests might need |
| 6291 | to be re-instated. Given, however, that the tests were only |
| 6292 | enabled when momentary breakpoints were not being used, I |
| 6293 | suspect that it won't be the case. |
| 6294 | |
| 6295 | NOTE: kettenis/2004-02-05: Indeed such checks don't seem to |
| 6296 | be necessary for call dummies on a non-executable stack on |
| 6297 | SPARC. */ |
| 6298 | |
| 6299 | /* See if the breakpoints module can explain the signal. */ |
| 6300 | random_signal |
| 6301 | = !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat, |
| 6302 | ecs->event_thread->suspend.stop_signal); |
| 6303 | |
| 6304 | /* Maybe this was a trap for a software breakpoint that has since |
| 6305 | been removed. */ |
| 6306 | if (random_signal && target_stopped_by_sw_breakpoint ()) |
| 6307 | { |
| 6308 | if (gdbarch_program_breakpoint_here_p (gdbarch, |
| 6309 | ecs->event_thread->suspend.stop_pc)) |
| 6310 | { |
| 6311 | struct regcache *regcache; |
| 6312 | int decr_pc; |
| 6313 | |
| 6314 | /* Re-adjust PC to what the program would see if GDB was not |
| 6315 | debugging it. */ |
| 6316 | regcache = get_thread_regcache (ecs->event_thread); |
| 6317 | decr_pc = gdbarch_decr_pc_after_break (gdbarch); |
| 6318 | if (decr_pc != 0) |
| 6319 | { |
| 6320 | gdb::optional<scoped_restore_tmpl<int>> |
| 6321 | restore_operation_disable; |
| 6322 | |
| 6323 | if (record_full_is_used ()) |
| 6324 | restore_operation_disable.emplace |
| 6325 | (record_full_gdb_operation_disable_set ()); |
| 6326 | |
| 6327 | regcache_write_pc (regcache, |
| 6328 | ecs->event_thread->suspend.stop_pc + decr_pc); |
| 6329 | } |
| 6330 | } |
| 6331 | else |
| 6332 | { |
| 6333 | /* A delayed software breakpoint event. Ignore the trap. */ |
| 6334 | infrun_debug_printf ("delayed software breakpoint trap, ignoring"); |
| 6335 | random_signal = 0; |
| 6336 | } |
| 6337 | } |
| 6338 | |
| 6339 | /* Maybe this was a trap for a hardware breakpoint/watchpoint that |
| 6340 | has since been removed. */ |
| 6341 | if (random_signal && target_stopped_by_hw_breakpoint ()) |
| 6342 | { |
| 6343 | /* A delayed hardware breakpoint event. Ignore the trap. */ |
| 6344 | infrun_debug_printf ("delayed hardware breakpoint/watchpoint " |
| 6345 | "trap, ignoring"); |
| 6346 | random_signal = 0; |
| 6347 | } |
| 6348 | |
| 6349 | /* If not, perhaps stepping/nexting can. */ |
| 6350 | if (random_signal) |
| 6351 | random_signal = !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP |
| 6352 | && currently_stepping (ecs->event_thread)); |
| 6353 | |
| 6354 | /* Perhaps the thread hit a single-step breakpoint of _another_ |
| 6355 | thread. Single-step breakpoints are transparent to the |
| 6356 | breakpoints module. */ |
| 6357 | if (random_signal) |
| 6358 | random_signal = !ecs->hit_singlestep_breakpoint; |
| 6359 | |
| 6360 | /* No? Perhaps we got a moribund watchpoint. */ |
| 6361 | if (random_signal) |
| 6362 | random_signal = !stopped_by_watchpoint; |
| 6363 | |
| 6364 | /* Always stop if the user explicitly requested this thread to |
| 6365 | remain stopped. */ |
| 6366 | if (ecs->event_thread->stop_requested) |
| 6367 | { |
| 6368 | random_signal = 1; |
| 6369 | infrun_debug_printf ("user-requested stop"); |
| 6370 | } |
| 6371 | |
| 6372 | /* For the program's own signals, act according to |
| 6373 | the signal handling tables. */ |
| 6374 | |
| 6375 | if (random_signal) |
| 6376 | { |
| 6377 | /* Signal not for debugging purposes. */ |
| 6378 | enum gdb_signal stop_signal = ecs->event_thread->suspend.stop_signal; |
| 6379 | |
| 6380 | infrun_debug_printf ("random signal (%s)", |
| 6381 | gdb_signal_to_symbol_string (stop_signal)); |
| 6382 | |
| 6383 | stopped_by_random_signal = 1; |
| 6384 | |
| 6385 | /* Always stop on signals if we're either just gaining control |
| 6386 | of the program, or the user explicitly requested this thread |
| 6387 | to remain stopped. */ |
| 6388 | if (stop_soon != NO_STOP_QUIETLY |
| 6389 | || ecs->event_thread->stop_requested |
| 6390 | || signal_stop_state (ecs->event_thread->suspend.stop_signal)) |
| 6391 | { |
| 6392 | stop_waiting (ecs); |
| 6393 | return; |
| 6394 | } |
| 6395 | |
| 6396 | /* Notify observers the signal has "handle print" set. Note we |
| 6397 | returned early above if stopping; normal_stop handles the |
| 6398 | printing in that case. */ |
| 6399 | if (signal_print[ecs->event_thread->suspend.stop_signal]) |
| 6400 | { |
| 6401 | /* The signal table tells us to print about this signal. */ |
| 6402 | target_terminal::ours_for_output (); |
| 6403 | gdb::observers::signal_received.notify (ecs->event_thread->suspend.stop_signal); |
| 6404 | target_terminal::inferior (); |
| 6405 | } |
| 6406 | |
| 6407 | /* Clear the signal if it should not be passed. */ |
| 6408 | if (signal_program[ecs->event_thread->suspend.stop_signal] == 0) |
| 6409 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 6410 | |
| 6411 | if (ecs->event_thread->prev_pc == ecs->event_thread->suspend.stop_pc |
| 6412 | && ecs->event_thread->control.trap_expected |
| 6413 | && ecs->event_thread->control.step_resume_breakpoint == NULL) |
| 6414 | { |
| 6415 | /* We were just starting a new sequence, attempting to |
| 6416 | single-step off of a breakpoint and expecting a SIGTRAP. |
| 6417 | Instead this signal arrives. This signal will take us out |
| 6418 | of the stepping range so GDB needs to remember to, when |
| 6419 | the signal handler returns, resume stepping off that |
| 6420 | breakpoint. */ |
| 6421 | /* To simplify things, "continue" is forced to use the same |
| 6422 | code paths as single-step - set a breakpoint at the |
| 6423 | signal return address and then, once hit, step off that |
| 6424 | breakpoint. */ |
| 6425 | infrun_debug_printf ("signal arrived while stepping over breakpoint"); |
| 6426 | |
| 6427 | insert_hp_step_resume_breakpoint_at_frame (frame); |
| 6428 | ecs->event_thread->step_after_step_resume_breakpoint = 1; |
| 6429 | /* Reset trap_expected to ensure breakpoints are re-inserted. */ |
| 6430 | ecs->event_thread->control.trap_expected = 0; |
| 6431 | |
| 6432 | /* If we were nexting/stepping some other thread, switch to |
| 6433 | it, so that we don't continue it, losing control. */ |
| 6434 | if (!switch_back_to_stepped_thread (ecs)) |
| 6435 | keep_going (ecs); |
| 6436 | return; |
| 6437 | } |
| 6438 | |
| 6439 | if (ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_0 |
| 6440 | && (pc_in_thread_step_range (ecs->event_thread->suspend.stop_pc, |
| 6441 | ecs->event_thread) |
| 6442 | || ecs->event_thread->control.step_range_end == 1) |
| 6443 | && frame_id_eq (get_stack_frame_id (frame), |
| 6444 | ecs->event_thread->control.step_stack_frame_id) |
| 6445 | && ecs->event_thread->control.step_resume_breakpoint == NULL) |
| 6446 | { |
| 6447 | /* The inferior is about to take a signal that will take it |
| 6448 | out of the single step range. Set a breakpoint at the |
| 6449 | current PC (which is presumably where the signal handler |
| 6450 | will eventually return) and then allow the inferior to |
| 6451 | run free. |
| 6452 | |
| 6453 | Note that this is only needed for a signal delivered |
| 6454 | while in the single-step range. Nested signals aren't a |
| 6455 | problem as they eventually all return. */ |
| 6456 | infrun_debug_printf ("signal may take us out of single-step range"); |
| 6457 | |
| 6458 | clear_step_over_info (); |
| 6459 | insert_hp_step_resume_breakpoint_at_frame (frame); |
| 6460 | ecs->event_thread->step_after_step_resume_breakpoint = 1; |
| 6461 | /* Reset trap_expected to ensure breakpoints are re-inserted. */ |
| 6462 | ecs->event_thread->control.trap_expected = 0; |
| 6463 | keep_going (ecs); |
| 6464 | return; |
| 6465 | } |
| 6466 | |
| 6467 | /* Note: step_resume_breakpoint may be non-NULL. This occurs |
| 6468 | when either there's a nested signal, or when there's a |
| 6469 | pending signal enabled just as the signal handler returns |
| 6470 | (leaving the inferior at the step-resume-breakpoint without |
| 6471 | actually executing it). Either way continue until the |
| 6472 | breakpoint is really hit. */ |
| 6473 | |
| 6474 | if (!switch_back_to_stepped_thread (ecs)) |
| 6475 | { |
| 6476 | infrun_debug_printf ("random signal, keep going"); |
| 6477 | |
| 6478 | keep_going (ecs); |
| 6479 | } |
| 6480 | return; |
| 6481 | } |
| 6482 | |
| 6483 | process_event_stop_test (ecs); |
| 6484 | } |
| 6485 | |
| 6486 | /* Come here when we've got some debug event / signal we can explain |
| 6487 | (IOW, not a random signal), and test whether it should cause a |
| 6488 | stop, or whether we should resume the inferior (transparently). |
| 6489 | E.g., could be a breakpoint whose condition evaluates false; we |
| 6490 | could be still stepping within the line; etc. */ |
| 6491 | |
| 6492 | static void |
| 6493 | process_event_stop_test (struct execution_control_state *ecs) |
| 6494 | { |
| 6495 | struct symtab_and_line stop_pc_sal; |
| 6496 | struct frame_info *frame; |
| 6497 | struct gdbarch *gdbarch; |
| 6498 | CORE_ADDR jmp_buf_pc; |
| 6499 | struct bpstat_what what; |
| 6500 | |
| 6501 | /* Handle cases caused by hitting a breakpoint. */ |
| 6502 | |
| 6503 | frame = get_current_frame (); |
| 6504 | gdbarch = get_frame_arch (frame); |
| 6505 | |
| 6506 | what = bpstat_what (ecs->event_thread->control.stop_bpstat); |
| 6507 | |
| 6508 | if (what.call_dummy) |
| 6509 | { |
| 6510 | stop_stack_dummy = what.call_dummy; |
| 6511 | } |
| 6512 | |
| 6513 | /* A few breakpoint types have callbacks associated (e.g., |
| 6514 | bp_jit_event). Run them now. */ |
| 6515 | bpstat_run_callbacks (ecs->event_thread->control.stop_bpstat); |
| 6516 | |
| 6517 | /* If we hit an internal event that triggers symbol changes, the |
| 6518 | current frame will be invalidated within bpstat_what (e.g., if we |
| 6519 | hit an internal solib event). Re-fetch it. */ |
| 6520 | frame = get_current_frame (); |
| 6521 | gdbarch = get_frame_arch (frame); |
| 6522 | |
| 6523 | switch (what.main_action) |
| 6524 | { |
| 6525 | case BPSTAT_WHAT_SET_LONGJMP_RESUME: |
| 6526 | /* If we hit the breakpoint at longjmp while stepping, we |
| 6527 | install a momentary breakpoint at the target of the |
| 6528 | jmp_buf. */ |
| 6529 | |
| 6530 | infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME"); |
| 6531 | |
| 6532 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6533 | |
| 6534 | if (what.is_longjmp) |
| 6535 | { |
| 6536 | struct value *arg_value; |
| 6537 | |
| 6538 | /* If we set the longjmp breakpoint via a SystemTap probe, |
| 6539 | then use it to extract the arguments. The destination PC |
| 6540 | is the third argument to the probe. */ |
| 6541 | arg_value = probe_safe_evaluate_at_pc (frame, 2); |
| 6542 | if (arg_value) |
| 6543 | { |
| 6544 | jmp_buf_pc = value_as_address (arg_value); |
| 6545 | jmp_buf_pc = gdbarch_addr_bits_remove (gdbarch, jmp_buf_pc); |
| 6546 | } |
| 6547 | else if (!gdbarch_get_longjmp_target_p (gdbarch) |
| 6548 | || !gdbarch_get_longjmp_target (gdbarch, |
| 6549 | frame, &jmp_buf_pc)) |
| 6550 | { |
| 6551 | infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME " |
| 6552 | "(!gdbarch_get_longjmp_target)"); |
| 6553 | keep_going (ecs); |
| 6554 | return; |
| 6555 | } |
| 6556 | |
| 6557 | /* Insert a breakpoint at resume address. */ |
| 6558 | insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc); |
| 6559 | } |
| 6560 | else |
| 6561 | check_exception_resume (ecs, frame); |
| 6562 | keep_going (ecs); |
| 6563 | return; |
| 6564 | |
| 6565 | case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME: |
| 6566 | { |
| 6567 | struct frame_info *init_frame; |
| 6568 | |
| 6569 | /* There are several cases to consider. |
| 6570 | |
| 6571 | 1. The initiating frame no longer exists. In this case we |
| 6572 | must stop, because the exception or longjmp has gone too |
| 6573 | far. |
| 6574 | |
| 6575 | 2. The initiating frame exists, and is the same as the |
| 6576 | current frame. We stop, because the exception or longjmp |
| 6577 | has been caught. |
| 6578 | |
| 6579 | 3. The initiating frame exists and is different from the |
| 6580 | current frame. This means the exception or longjmp has |
| 6581 | been caught beneath the initiating frame, so keep going. |
| 6582 | |
| 6583 | 4. longjmp breakpoint has been placed just to protect |
| 6584 | against stale dummy frames and user is not interested in |
| 6585 | stopping around longjmps. */ |
| 6586 | |
| 6587 | infrun_debug_printf ("BPSTAT_WHAT_CLEAR_LONGJMP_RESUME"); |
| 6588 | |
| 6589 | gdb_assert (ecs->event_thread->control.exception_resume_breakpoint |
| 6590 | != NULL); |
| 6591 | delete_exception_resume_breakpoint (ecs->event_thread); |
| 6592 | |
| 6593 | if (what.is_longjmp) |
| 6594 | { |
| 6595 | check_longjmp_breakpoint_for_call_dummy (ecs->event_thread); |
| 6596 | |
| 6597 | if (!frame_id_p (ecs->event_thread->initiating_frame)) |
| 6598 | { |
| 6599 | /* Case 4. */ |
| 6600 | keep_going (ecs); |
| 6601 | return; |
| 6602 | } |
| 6603 | } |
| 6604 | |
| 6605 | init_frame = frame_find_by_id (ecs->event_thread->initiating_frame); |
| 6606 | |
| 6607 | if (init_frame) |
| 6608 | { |
| 6609 | struct frame_id current_id |
| 6610 | = get_frame_id (get_current_frame ()); |
| 6611 | if (frame_id_eq (current_id, |
| 6612 | ecs->event_thread->initiating_frame)) |
| 6613 | { |
| 6614 | /* Case 2. Fall through. */ |
| 6615 | } |
| 6616 | else |
| 6617 | { |
| 6618 | /* Case 3. */ |
| 6619 | keep_going (ecs); |
| 6620 | return; |
| 6621 | } |
| 6622 | } |
| 6623 | |
| 6624 | /* For Cases 1 and 2, remove the step-resume breakpoint, if it |
| 6625 | exists. */ |
| 6626 | delete_step_resume_breakpoint (ecs->event_thread); |
| 6627 | |
| 6628 | end_stepping_range (ecs); |
| 6629 | } |
| 6630 | return; |
| 6631 | |
| 6632 | case BPSTAT_WHAT_SINGLE: |
| 6633 | infrun_debug_printf ("BPSTAT_WHAT_SINGLE"); |
| 6634 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6635 | /* Still need to check other stuff, at least the case where we |
| 6636 | are stepping and step out of the right range. */ |
| 6637 | break; |
| 6638 | |
| 6639 | case BPSTAT_WHAT_STEP_RESUME: |
| 6640 | infrun_debug_printf ("BPSTAT_WHAT_STEP_RESUME"); |
| 6641 | |
| 6642 | delete_step_resume_breakpoint (ecs->event_thread); |
| 6643 | if (ecs->event_thread->control.proceed_to_finish |
| 6644 | && execution_direction == EXEC_REVERSE) |
| 6645 | { |
| 6646 | struct thread_info *tp = ecs->event_thread; |
| 6647 | |
| 6648 | /* We are finishing a function in reverse, and just hit the |
| 6649 | step-resume breakpoint at the start address of the |
| 6650 | function, and we're almost there -- just need to back up |
| 6651 | by one more single-step, which should take us back to the |
| 6652 | function call. */ |
| 6653 | tp->control.step_range_start = tp->control.step_range_end = 1; |
| 6654 | keep_going (ecs); |
| 6655 | return; |
| 6656 | } |
| 6657 | fill_in_stop_func (gdbarch, ecs); |
| 6658 | if (ecs->event_thread->suspend.stop_pc == ecs->stop_func_start |
| 6659 | && execution_direction == EXEC_REVERSE) |
| 6660 | { |
| 6661 | /* We are stepping over a function call in reverse, and just |
| 6662 | hit the step-resume breakpoint at the start address of |
| 6663 | the function. Go back to single-stepping, which should |
| 6664 | take us back to the function call. */ |
| 6665 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6666 | keep_going (ecs); |
| 6667 | return; |
| 6668 | } |
| 6669 | break; |
| 6670 | |
| 6671 | case BPSTAT_WHAT_STOP_NOISY: |
| 6672 | infrun_debug_printf ("BPSTAT_WHAT_STOP_NOISY"); |
| 6673 | stop_print_frame = true; |
| 6674 | |
| 6675 | /* Assume the thread stopped for a breakpoint. We'll still check |
| 6676 | whether a/the breakpoint is there when the thread is next |
| 6677 | resumed. */ |
| 6678 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6679 | |
| 6680 | stop_waiting (ecs); |
| 6681 | return; |
| 6682 | |
| 6683 | case BPSTAT_WHAT_STOP_SILENT: |
| 6684 | infrun_debug_printf ("BPSTAT_WHAT_STOP_SILENT"); |
| 6685 | stop_print_frame = false; |
| 6686 | |
| 6687 | /* Assume the thread stopped for a breakpoint. We'll still check |
| 6688 | whether a/the breakpoint is there when the thread is next |
| 6689 | resumed. */ |
| 6690 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6691 | stop_waiting (ecs); |
| 6692 | return; |
| 6693 | |
| 6694 | case BPSTAT_WHAT_HP_STEP_RESUME: |
| 6695 | infrun_debug_printf ("BPSTAT_WHAT_HP_STEP_RESUME"); |
| 6696 | |
| 6697 | delete_step_resume_breakpoint (ecs->event_thread); |
| 6698 | if (ecs->event_thread->step_after_step_resume_breakpoint) |
| 6699 | { |
| 6700 | /* Back when the step-resume breakpoint was inserted, we |
| 6701 | were trying to single-step off a breakpoint. Go back to |
| 6702 | doing that. */ |
| 6703 | ecs->event_thread->step_after_step_resume_breakpoint = 0; |
| 6704 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6705 | keep_going (ecs); |
| 6706 | return; |
| 6707 | } |
| 6708 | break; |
| 6709 | |
| 6710 | case BPSTAT_WHAT_KEEP_CHECKING: |
| 6711 | break; |
| 6712 | } |
| 6713 | |
| 6714 | /* If we stepped a permanent breakpoint and we had a high priority |
| 6715 | step-resume breakpoint for the address we stepped, but we didn't |
| 6716 | hit it, then we must have stepped into the signal handler. The |
| 6717 | step-resume was only necessary to catch the case of _not_ |
| 6718 | stepping into the handler, so delete it, and fall through to |
| 6719 | checking whether the step finished. */ |
| 6720 | if (ecs->event_thread->stepped_breakpoint) |
| 6721 | { |
| 6722 | struct breakpoint *sr_bp |
| 6723 | = ecs->event_thread->control.step_resume_breakpoint; |
| 6724 | |
| 6725 | if (sr_bp != NULL |
| 6726 | && sr_bp->loc->permanent |
| 6727 | && sr_bp->type == bp_hp_step_resume |
| 6728 | && sr_bp->loc->address == ecs->event_thread->prev_pc) |
| 6729 | { |
| 6730 | infrun_debug_printf ("stepped permanent breakpoint, stopped in handler"); |
| 6731 | delete_step_resume_breakpoint (ecs->event_thread); |
| 6732 | ecs->event_thread->step_after_step_resume_breakpoint = 0; |
| 6733 | } |
| 6734 | } |
| 6735 | |
| 6736 | /* We come here if we hit a breakpoint but should not stop for it. |
| 6737 | Possibly we also were stepping and should stop for that. So fall |
| 6738 | through and test for stepping. But, if not stepping, do not |
| 6739 | stop. */ |
| 6740 | |
| 6741 | /* In all-stop mode, if we're currently stepping but have stopped in |
| 6742 | some other thread, we need to switch back to the stepped thread. */ |
| 6743 | if (switch_back_to_stepped_thread (ecs)) |
| 6744 | return; |
| 6745 | |
| 6746 | if (ecs->event_thread->control.step_resume_breakpoint) |
| 6747 | { |
| 6748 | infrun_debug_printf ("step-resume breakpoint is inserted"); |
| 6749 | |
| 6750 | /* Having a step-resume breakpoint overrides anything |
| 6751 | else having to do with stepping commands until |
| 6752 | that breakpoint is reached. */ |
| 6753 | keep_going (ecs); |
| 6754 | return; |
| 6755 | } |
| 6756 | |
| 6757 | if (ecs->event_thread->control.step_range_end == 0) |
| 6758 | { |
| 6759 | infrun_debug_printf ("no stepping, continue"); |
| 6760 | /* Likewise if we aren't even stepping. */ |
| 6761 | keep_going (ecs); |
| 6762 | return; |
| 6763 | } |
| 6764 | |
| 6765 | /* Re-fetch current thread's frame in case the code above caused |
| 6766 | the frame cache to be re-initialized, making our FRAME variable |
| 6767 | a dangling pointer. */ |
| 6768 | frame = get_current_frame (); |
| 6769 | gdbarch = get_frame_arch (frame); |
| 6770 | fill_in_stop_func (gdbarch, ecs); |
| 6771 | |
| 6772 | /* If stepping through a line, keep going if still within it. |
| 6773 | |
| 6774 | Note that step_range_end is the address of the first instruction |
| 6775 | beyond the step range, and NOT the address of the last instruction |
| 6776 | within it! |
| 6777 | |
| 6778 | Note also that during reverse execution, we may be stepping |
| 6779 | through a function epilogue and therefore must detect when |
| 6780 | the current-frame changes in the middle of a line. */ |
| 6781 | |
| 6782 | if (pc_in_thread_step_range (ecs->event_thread->suspend.stop_pc, |
| 6783 | ecs->event_thread) |
| 6784 | && (execution_direction != EXEC_REVERSE |
| 6785 | || frame_id_eq (get_frame_id (frame), |
| 6786 | ecs->event_thread->control.step_frame_id))) |
| 6787 | { |
| 6788 | infrun_debug_printf |
| 6789 | ("stepping inside range [%s-%s]", |
| 6790 | paddress (gdbarch, ecs->event_thread->control.step_range_start), |
| 6791 | paddress (gdbarch, ecs->event_thread->control.step_range_end)); |
| 6792 | |
| 6793 | /* Tentatively re-enable range stepping; `resume' disables it if |
| 6794 | necessary (e.g., if we're stepping over a breakpoint or we |
| 6795 | have software watchpoints). */ |
| 6796 | ecs->event_thread->control.may_range_step = 1; |
| 6797 | |
| 6798 | /* When stepping backward, stop at beginning of line range |
| 6799 | (unless it's the function entry point, in which case |
| 6800 | keep going back to the call point). */ |
| 6801 | CORE_ADDR stop_pc = ecs->event_thread->suspend.stop_pc; |
| 6802 | if (stop_pc == ecs->event_thread->control.step_range_start |
| 6803 | && stop_pc != ecs->stop_func_start |
| 6804 | && execution_direction == EXEC_REVERSE) |
| 6805 | end_stepping_range (ecs); |
| 6806 | else |
| 6807 | keep_going (ecs); |
| 6808 | |
| 6809 | return; |
| 6810 | } |
| 6811 | |
| 6812 | /* We stepped out of the stepping range. */ |
| 6813 | |
| 6814 | /* If we are stepping at the source level and entered the runtime |
| 6815 | loader dynamic symbol resolution code... |
| 6816 | |
| 6817 | EXEC_FORWARD: we keep on single stepping until we exit the run |
| 6818 | time loader code and reach the callee's address. |
| 6819 | |
| 6820 | EXEC_REVERSE: we've already executed the callee (backward), and |
| 6821 | the runtime loader code is handled just like any other |
| 6822 | undebuggable function call. Now we need only keep stepping |
| 6823 | backward through the trampoline code, and that's handled further |
| 6824 | down, so there is nothing for us to do here. */ |
| 6825 | |
| 6826 | if (execution_direction != EXEC_REVERSE |
| 6827 | && ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE |
| 6828 | && in_solib_dynsym_resolve_code (ecs->event_thread->suspend.stop_pc)) |
| 6829 | { |
| 6830 | CORE_ADDR pc_after_resolver = |
| 6831 | gdbarch_skip_solib_resolver (gdbarch, |
| 6832 | ecs->event_thread->suspend.stop_pc); |
| 6833 | |
| 6834 | infrun_debug_printf ("stepped into dynsym resolve code"); |
| 6835 | |
| 6836 | if (pc_after_resolver) |
| 6837 | { |
| 6838 | /* Set up a step-resume breakpoint at the address |
| 6839 | indicated by SKIP_SOLIB_RESOLVER. */ |
| 6840 | symtab_and_line sr_sal; |
| 6841 | sr_sal.pc = pc_after_resolver; |
| 6842 | sr_sal.pspace = get_frame_program_space (frame); |
| 6843 | |
| 6844 | insert_step_resume_breakpoint_at_sal (gdbarch, |
| 6845 | sr_sal, null_frame_id); |
| 6846 | } |
| 6847 | |
| 6848 | keep_going (ecs); |
| 6849 | return; |
| 6850 | } |
| 6851 | |
| 6852 | /* Step through an indirect branch thunk. */ |
| 6853 | if (ecs->event_thread->control.step_over_calls != STEP_OVER_NONE |
| 6854 | && gdbarch_in_indirect_branch_thunk (gdbarch, |
| 6855 | ecs->event_thread->suspend.stop_pc)) |
| 6856 | { |
| 6857 | infrun_debug_printf ("stepped into indirect branch thunk"); |
| 6858 | keep_going (ecs); |
| 6859 | return; |
| 6860 | } |
| 6861 | |
| 6862 | if (ecs->event_thread->control.step_range_end != 1 |
| 6863 | && (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE |
| 6864 | || ecs->event_thread->control.step_over_calls == STEP_OVER_ALL) |
| 6865 | && get_frame_type (frame) == SIGTRAMP_FRAME) |
| 6866 | { |
| 6867 | infrun_debug_printf ("stepped into signal trampoline"); |
| 6868 | /* The inferior, while doing a "step" or "next", has ended up in |
| 6869 | a signal trampoline (either by a signal being delivered or by |
| 6870 | the signal handler returning). Just single-step until the |
| 6871 | inferior leaves the trampoline (either by calling the handler |
| 6872 | or returning). */ |
| 6873 | keep_going (ecs); |
| 6874 | return; |
| 6875 | } |
| 6876 | |
| 6877 | /* If we're in the return path from a shared library trampoline, |
| 6878 | we want to proceed through the trampoline when stepping. */ |
| 6879 | /* macro/2012-04-25: This needs to come before the subroutine |
| 6880 | call check below as on some targets return trampolines look |
| 6881 | like subroutine calls (MIPS16 return thunks). */ |
| 6882 | if (gdbarch_in_solib_return_trampoline (gdbarch, |
| 6883 | ecs->event_thread->suspend.stop_pc, |
| 6884 | ecs->stop_func_name) |
| 6885 | && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE) |
| 6886 | { |
| 6887 | /* Determine where this trampoline returns. */ |
| 6888 | CORE_ADDR stop_pc = ecs->event_thread->suspend.stop_pc; |
| 6889 | CORE_ADDR real_stop_pc |
| 6890 | = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc); |
| 6891 | |
| 6892 | infrun_debug_printf ("stepped into solib return tramp"); |
| 6893 | |
| 6894 | /* Only proceed through if we know where it's going. */ |
| 6895 | if (real_stop_pc) |
| 6896 | { |
| 6897 | /* And put the step-breakpoint there and go until there. */ |
| 6898 | symtab_and_line sr_sal; |
| 6899 | sr_sal.pc = real_stop_pc; |
| 6900 | sr_sal.section = find_pc_overlay (sr_sal.pc); |
| 6901 | sr_sal.pspace = get_frame_program_space (frame); |
| 6902 | |
| 6903 | /* Do not specify what the fp should be when we stop since |
| 6904 | on some machines the prologue is where the new fp value |
| 6905 | is established. */ |
| 6906 | insert_step_resume_breakpoint_at_sal (gdbarch, |
| 6907 | sr_sal, null_frame_id); |
| 6908 | |
| 6909 | /* Restart without fiddling with the step ranges or |
| 6910 | other state. */ |
| 6911 | keep_going (ecs); |
| 6912 | return; |
| 6913 | } |
| 6914 | } |
| 6915 | |
| 6916 | /* Check for subroutine calls. The check for the current frame |
| 6917 | equalling the step ID is not necessary - the check of the |
| 6918 | previous frame's ID is sufficient - but it is a common case and |
| 6919 | cheaper than checking the previous frame's ID. |
| 6920 | |
| 6921 | NOTE: frame_id_eq will never report two invalid frame IDs as |
| 6922 | being equal, so to get into this block, both the current and |
| 6923 | previous frame must have valid frame IDs. */ |
| 6924 | /* The outer_frame_id check is a heuristic to detect stepping |
| 6925 | through startup code. If we step over an instruction which |
| 6926 | sets the stack pointer from an invalid value to a valid value, |
| 6927 | we may detect that as a subroutine call from the mythical |
| 6928 | "outermost" function. This could be fixed by marking |
| 6929 | outermost frames as !stack_p,code_p,special_p. Then the |
| 6930 | initial outermost frame, before sp was valid, would |
| 6931 | have code_addr == &_start. See the comment in frame_id_eq |
| 6932 | for more. */ |
| 6933 | if (!frame_id_eq (get_stack_frame_id (frame), |
| 6934 | ecs->event_thread->control.step_stack_frame_id) |
| 6935 | && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()), |
| 6936 | ecs->event_thread->control.step_stack_frame_id) |
| 6937 | && (!frame_id_eq (ecs->event_thread->control.step_stack_frame_id, |
| 6938 | outer_frame_id) |
| 6939 | || (ecs->event_thread->control.step_start_function |
| 6940 | != find_pc_function (ecs->event_thread->suspend.stop_pc))))) |
| 6941 | { |
| 6942 | CORE_ADDR stop_pc = ecs->event_thread->suspend.stop_pc; |
| 6943 | CORE_ADDR real_stop_pc; |
| 6944 | |
| 6945 | infrun_debug_printf ("stepped into subroutine"); |
| 6946 | |
| 6947 | if (ecs->event_thread->control.step_over_calls == STEP_OVER_NONE) |
| 6948 | { |
| 6949 | /* I presume that step_over_calls is only 0 when we're |
| 6950 | supposed to be stepping at the assembly language level |
| 6951 | ("stepi"). Just stop. */ |
| 6952 | /* And this works the same backward as frontward. MVS */ |
| 6953 | end_stepping_range (ecs); |
| 6954 | return; |
| 6955 | } |
| 6956 | |
| 6957 | /* Reverse stepping through solib trampolines. */ |
| 6958 | |
| 6959 | if (execution_direction == EXEC_REVERSE |
| 6960 | && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE |
| 6961 | && (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc) |
| 6962 | || (ecs->stop_func_start == 0 |
| 6963 | && in_solib_dynsym_resolve_code (stop_pc)))) |
| 6964 | { |
| 6965 | /* Any solib trampoline code can be handled in reverse |
| 6966 | by simply continuing to single-step. We have already |
| 6967 | executed the solib function (backwards), and a few |
| 6968 | steps will take us back through the trampoline to the |
| 6969 | caller. */ |
| 6970 | keep_going (ecs); |
| 6971 | return; |
| 6972 | } |
| 6973 | |
| 6974 | if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL) |
| 6975 | { |
| 6976 | /* We're doing a "next". |
| 6977 | |
| 6978 | Normal (forward) execution: set a breakpoint at the |
| 6979 | callee's return address (the address at which the caller |
| 6980 | will resume). |
| 6981 | |
| 6982 | Reverse (backward) execution. set the step-resume |
| 6983 | breakpoint at the start of the function that we just |
| 6984 | stepped into (backwards), and continue to there. When we |
| 6985 | get there, we'll need to single-step back to the caller. */ |
| 6986 | |
| 6987 | if (execution_direction == EXEC_REVERSE) |
| 6988 | { |
| 6989 | /* If we're already at the start of the function, we've either |
| 6990 | just stepped backward into a single instruction function, |
| 6991 | or stepped back out of a signal handler to the first instruction |
| 6992 | of the function. Just keep going, which will single-step back |
| 6993 | to the caller. */ |
| 6994 | if (ecs->stop_func_start != stop_pc && ecs->stop_func_start != 0) |
| 6995 | { |
| 6996 | /* Normal function call return (static or dynamic). */ |
| 6997 | symtab_and_line sr_sal; |
| 6998 | sr_sal.pc = ecs->stop_func_start; |
| 6999 | sr_sal.pspace = get_frame_program_space (frame); |
| 7000 | insert_step_resume_breakpoint_at_sal (gdbarch, |
| 7001 | sr_sal, null_frame_id); |
| 7002 | } |
| 7003 | } |
| 7004 | else |
| 7005 | insert_step_resume_breakpoint_at_caller (frame); |
| 7006 | |
| 7007 | keep_going (ecs); |
| 7008 | return; |
| 7009 | } |
| 7010 | |
| 7011 | /* If we are in a function call trampoline (a stub between the |
| 7012 | calling routine and the real function), locate the real |
| 7013 | function. That's what tells us (a) whether we want to step |
| 7014 | into it at all, and (b) what prologue we want to run to the |
| 7015 | end of, if we do step into it. */ |
| 7016 | real_stop_pc = skip_language_trampoline (frame, stop_pc); |
| 7017 | if (real_stop_pc == 0) |
| 7018 | real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc); |
| 7019 | if (real_stop_pc != 0) |
| 7020 | ecs->stop_func_start = real_stop_pc; |
| 7021 | |
| 7022 | if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc)) |
| 7023 | { |
| 7024 | symtab_and_line sr_sal; |
| 7025 | sr_sal.pc = ecs->stop_func_start; |
| 7026 | sr_sal.pspace = get_frame_program_space (frame); |
| 7027 | |
| 7028 | insert_step_resume_breakpoint_at_sal (gdbarch, |
| 7029 | sr_sal, null_frame_id); |
| 7030 | keep_going (ecs); |
| 7031 | return; |
| 7032 | } |
| 7033 | |
| 7034 | /* If we have line number information for the function we are |
| 7035 | thinking of stepping into and the function isn't on the skip |
| 7036 | list, step into it. |
| 7037 | |
| 7038 | If there are several symtabs at that PC (e.g. with include |
| 7039 | files), just want to know whether *any* of them have line |
| 7040 | numbers. find_pc_line handles this. */ |
| 7041 | { |
| 7042 | struct symtab_and_line tmp_sal; |
| 7043 | |
| 7044 | tmp_sal = find_pc_line (ecs->stop_func_start, 0); |
| 7045 | if (tmp_sal.line != 0 |
| 7046 | && !function_name_is_marked_for_skip (ecs->stop_func_name, |
| 7047 | tmp_sal) |
| 7048 | && !inline_frame_is_marked_for_skip (true, ecs->event_thread)) |
| 7049 | { |
| 7050 | if (execution_direction == EXEC_REVERSE) |
| 7051 | handle_step_into_function_backward (gdbarch, ecs); |
| 7052 | else |
| 7053 | handle_step_into_function (gdbarch, ecs); |
| 7054 | return; |
| 7055 | } |
| 7056 | } |
| 7057 | |
| 7058 | /* If we have no line number and the step-stop-if-no-debug is |
| 7059 | set, we stop the step so that the user has a chance to switch |
| 7060 | in assembly mode. */ |
| 7061 | if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE |
| 7062 | && step_stop_if_no_debug) |
| 7063 | { |
| 7064 | end_stepping_range (ecs); |
| 7065 | return; |
| 7066 | } |
| 7067 | |
| 7068 | if (execution_direction == EXEC_REVERSE) |
| 7069 | { |
| 7070 | /* If we're already at the start of the function, we've either just |
| 7071 | stepped backward into a single instruction function without line |
| 7072 | number info, or stepped back out of a signal handler to the first |
| 7073 | instruction of the function without line number info. Just keep |
| 7074 | going, which will single-step back to the caller. */ |
| 7075 | if (ecs->stop_func_start != stop_pc) |
| 7076 | { |
| 7077 | /* Set a breakpoint at callee's start address. |
| 7078 | From there we can step once and be back in the caller. */ |
| 7079 | symtab_and_line sr_sal; |
| 7080 | sr_sal.pc = ecs->stop_func_start; |
| 7081 | sr_sal.pspace = get_frame_program_space (frame); |
| 7082 | insert_step_resume_breakpoint_at_sal (gdbarch, |
| 7083 | sr_sal, null_frame_id); |
| 7084 | } |
| 7085 | } |
| 7086 | else |
| 7087 | /* Set a breakpoint at callee's return address (the address |
| 7088 | at which the caller will resume). */ |
| 7089 | insert_step_resume_breakpoint_at_caller (frame); |
| 7090 | |
| 7091 | keep_going (ecs); |
| 7092 | return; |
| 7093 | } |
| 7094 | |
| 7095 | /* Reverse stepping through solib trampolines. */ |
| 7096 | |
| 7097 | if (execution_direction == EXEC_REVERSE |
| 7098 | && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE) |
| 7099 | { |
| 7100 | CORE_ADDR stop_pc = ecs->event_thread->suspend.stop_pc; |
| 7101 | |
| 7102 | if (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc) |
| 7103 | || (ecs->stop_func_start == 0 |
| 7104 | && in_solib_dynsym_resolve_code (stop_pc))) |
| 7105 | { |
| 7106 | /* Any solib trampoline code can be handled in reverse |
| 7107 | by simply continuing to single-step. We have already |
| 7108 | executed the solib function (backwards), and a few |
| 7109 | steps will take us back through the trampoline to the |
| 7110 | caller. */ |
| 7111 | keep_going (ecs); |
| 7112 | return; |
| 7113 | } |
| 7114 | else if (in_solib_dynsym_resolve_code (stop_pc)) |
| 7115 | { |
| 7116 | /* Stepped backward into the solib dynsym resolver. |
| 7117 | Set a breakpoint at its start and continue, then |
| 7118 | one more step will take us out. */ |
| 7119 | symtab_and_line sr_sal; |
| 7120 | sr_sal.pc = ecs->stop_func_start; |
| 7121 | sr_sal.pspace = get_frame_program_space (frame); |
| 7122 | insert_step_resume_breakpoint_at_sal (gdbarch, |
| 7123 | sr_sal, null_frame_id); |
| 7124 | keep_going (ecs); |
| 7125 | return; |
| 7126 | } |
| 7127 | } |
| 7128 | |
| 7129 | /* This always returns the sal for the inner-most frame when we are in a |
| 7130 | stack of inlined frames, even if GDB actually believes that it is in a |
| 7131 | more outer frame. This is checked for below by calls to |
| 7132 | inline_skipped_frames. */ |
| 7133 | stop_pc_sal = find_pc_line (ecs->event_thread->suspend.stop_pc, 0); |
| 7134 | |
| 7135 | /* NOTE: tausq/2004-05-24: This if block used to be done before all |
| 7136 | the trampoline processing logic, however, there are some trampolines |
| 7137 | that have no names, so we should do trampoline handling first. */ |
| 7138 | if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE |
| 7139 | && ecs->stop_func_name == NULL |
| 7140 | && stop_pc_sal.line == 0) |
| 7141 | { |
| 7142 | infrun_debug_printf ("stepped into undebuggable function"); |
| 7143 | |
| 7144 | /* The inferior just stepped into, or returned to, an |
| 7145 | undebuggable function (where there is no debugging information |
| 7146 | and no line number corresponding to the address where the |
| 7147 | inferior stopped). Since we want to skip this kind of code, |
| 7148 | we keep going until the inferior returns from this |
| 7149 | function - unless the user has asked us not to (via |
| 7150 | set step-mode) or we no longer know how to get back |
| 7151 | to the call site. */ |
| 7152 | if (step_stop_if_no_debug |
| 7153 | || !frame_id_p (frame_unwind_caller_id (frame))) |
| 7154 | { |
| 7155 | /* If we have no line number and the step-stop-if-no-debug |
| 7156 | is set, we stop the step so that the user has a chance to |
| 7157 | switch in assembly mode. */ |
| 7158 | end_stepping_range (ecs); |
| 7159 | return; |
| 7160 | } |
| 7161 | else |
| 7162 | { |
| 7163 | /* Set a breakpoint at callee's return address (the address |
| 7164 | at which the caller will resume). */ |
| 7165 | insert_step_resume_breakpoint_at_caller (frame); |
| 7166 | keep_going (ecs); |
| 7167 | return; |
| 7168 | } |
| 7169 | } |
| 7170 | |
| 7171 | if (ecs->event_thread->control.step_range_end == 1) |
| 7172 | { |
| 7173 | /* It is stepi or nexti. We always want to stop stepping after |
| 7174 | one instruction. */ |
| 7175 | infrun_debug_printf ("stepi/nexti"); |
| 7176 | end_stepping_range (ecs); |
| 7177 | return; |
| 7178 | } |
| 7179 | |
| 7180 | if (stop_pc_sal.line == 0) |
| 7181 | { |
| 7182 | /* We have no line number information. That means to stop |
| 7183 | stepping (does this always happen right after one instruction, |
| 7184 | when we do "s" in a function with no line numbers, |
| 7185 | or can this happen as a result of a return or longjmp?). */ |
| 7186 | infrun_debug_printf ("line number info"); |
| 7187 | end_stepping_range (ecs); |
| 7188 | return; |
| 7189 | } |
| 7190 | |
| 7191 | /* Look for "calls" to inlined functions, part one. If the inline |
| 7192 | frame machinery detected some skipped call sites, we have entered |
| 7193 | a new inline function. */ |
| 7194 | |
| 7195 | if (frame_id_eq (get_frame_id (get_current_frame ()), |
| 7196 | ecs->event_thread->control.step_frame_id) |
| 7197 | && inline_skipped_frames (ecs->event_thread)) |
| 7198 | { |
| 7199 | infrun_debug_printf ("stepped into inlined function"); |
| 7200 | |
| 7201 | symtab_and_line call_sal = find_frame_sal (get_current_frame ()); |
| 7202 | |
| 7203 | if (ecs->event_thread->control.step_over_calls != STEP_OVER_ALL) |
| 7204 | { |
| 7205 | /* For "step", we're going to stop. But if the call site |
| 7206 | for this inlined function is on the same source line as |
| 7207 | we were previously stepping, go down into the function |
| 7208 | first. Otherwise stop at the call site. */ |
| 7209 | |
| 7210 | if (call_sal.line == ecs->event_thread->current_line |
| 7211 | && call_sal.symtab == ecs->event_thread->current_symtab) |
| 7212 | { |
| 7213 | step_into_inline_frame (ecs->event_thread); |
| 7214 | if (inline_frame_is_marked_for_skip (false, ecs->event_thread)) |
| 7215 | { |
| 7216 | keep_going (ecs); |
| 7217 | return; |
| 7218 | } |
| 7219 | } |
| 7220 | |
| 7221 | end_stepping_range (ecs); |
| 7222 | return; |
| 7223 | } |
| 7224 | else |
| 7225 | { |
| 7226 | /* For "next", we should stop at the call site if it is on a |
| 7227 | different source line. Otherwise continue through the |
| 7228 | inlined function. */ |
| 7229 | if (call_sal.line == ecs->event_thread->current_line |
| 7230 | && call_sal.symtab == ecs->event_thread->current_symtab) |
| 7231 | keep_going (ecs); |
| 7232 | else |
| 7233 | end_stepping_range (ecs); |
| 7234 | return; |
| 7235 | } |
| 7236 | } |
| 7237 | |
| 7238 | /* Look for "calls" to inlined functions, part two. If we are still |
| 7239 | in the same real function we were stepping through, but we have |
| 7240 | to go further up to find the exact frame ID, we are stepping |
| 7241 | through a more inlined call beyond its call site. */ |
| 7242 | |
| 7243 | if (get_frame_type (get_current_frame ()) == INLINE_FRAME |
| 7244 | && !frame_id_eq (get_frame_id (get_current_frame ()), |
| 7245 | ecs->event_thread->control.step_frame_id) |
| 7246 | && stepped_in_from (get_current_frame (), |
| 7247 | ecs->event_thread->control.step_frame_id)) |
| 7248 | { |
| 7249 | infrun_debug_printf ("stepping through inlined function"); |
| 7250 | |
| 7251 | if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL |
| 7252 | || inline_frame_is_marked_for_skip (false, ecs->event_thread)) |
| 7253 | keep_going (ecs); |
| 7254 | else |
| 7255 | end_stepping_range (ecs); |
| 7256 | return; |
| 7257 | } |
| 7258 | |
| 7259 | bool refresh_step_info = true; |
| 7260 | if ((ecs->event_thread->suspend.stop_pc == stop_pc_sal.pc) |
| 7261 | && (ecs->event_thread->current_line != stop_pc_sal.line |
| 7262 | || ecs->event_thread->current_symtab != stop_pc_sal.symtab)) |
| 7263 | { |
| 7264 | /* We are at a different line. */ |
| 7265 | |
| 7266 | if (stop_pc_sal.is_stmt) |
| 7267 | { |
| 7268 | /* We are at the start of a statement. |
| 7269 | |
| 7270 | So stop. Note that we don't stop if we step into the middle of a |
| 7271 | statement. That is said to make things like for (;;) statements |
| 7272 | work better. */ |
| 7273 | infrun_debug_printf ("stepped to a different line"); |
| 7274 | end_stepping_range (ecs); |
| 7275 | return; |
| 7276 | } |
| 7277 | else if (frame_id_eq (get_frame_id (get_current_frame ()), |
| 7278 | ecs->event_thread->control.step_frame_id)) |
| 7279 | { |
| 7280 | /* We are not at the start of a statement, and we have not changed |
| 7281 | frame. |
| 7282 | |
| 7283 | We ignore this line table entry, and continue stepping forward, |
| 7284 | looking for a better place to stop. */ |
| 7285 | refresh_step_info = false; |
| 7286 | infrun_debug_printf ("stepped to a different line, but " |
| 7287 | "it's not the start of a statement"); |
| 7288 | } |
| 7289 | else |
| 7290 | { |
| 7291 | /* We are not the start of a statement, and we have changed frame. |
| 7292 | |
| 7293 | We ignore this line table entry, and continue stepping forward, |
| 7294 | looking for a better place to stop. Keep refresh_step_info at |
| 7295 | true to note that the frame has changed, but ignore the line |
| 7296 | number to make sure we don't ignore a subsequent entry with the |
| 7297 | same line number. */ |
| 7298 | stop_pc_sal.line = 0; |
| 7299 | infrun_debug_printf ("stepped to a different frame, but " |
| 7300 | "it's not the start of a statement"); |
| 7301 | } |
| 7302 | } |
| 7303 | |
| 7304 | /* We aren't done stepping. |
| 7305 | |
| 7306 | Optimize by setting the stepping range to the line. |
| 7307 | (We might not be in the original line, but if we entered a |
| 7308 | new line in mid-statement, we continue stepping. This makes |
| 7309 | things like for(;;) statements work better.) |
| 7310 | |
| 7311 | If we entered a SAL that indicates a non-statement line table entry, |
| 7312 | then we update the stepping range, but we don't update the step info, |
| 7313 | which includes things like the line number we are stepping away from. |
| 7314 | This means we will stop when we find a line table entry that is marked |
| 7315 | as is-statement, even if it matches the non-statement one we just |
| 7316 | stepped into. */ |
| 7317 | |
| 7318 | ecs->event_thread->control.step_range_start = stop_pc_sal.pc; |
| 7319 | ecs->event_thread->control.step_range_end = stop_pc_sal.end; |
| 7320 | ecs->event_thread->control.may_range_step = 1; |
| 7321 | if (refresh_step_info) |
| 7322 | set_step_info (ecs->event_thread, frame, stop_pc_sal); |
| 7323 | |
| 7324 | infrun_debug_printf ("keep going"); |
| 7325 | keep_going (ecs); |
| 7326 | } |
| 7327 | |
| 7328 | static bool restart_stepped_thread (process_stratum_target *resume_target, |
| 7329 | ptid_t resume_ptid); |
| 7330 | |
| 7331 | /* In all-stop mode, if we're currently stepping but have stopped in |
| 7332 | some other thread, we may need to switch back to the stepped |
| 7333 | thread. Returns true we set the inferior running, false if we left |
| 7334 | it stopped (and the event needs further processing). */ |
| 7335 | |
| 7336 | static bool |
| 7337 | switch_back_to_stepped_thread (struct execution_control_state *ecs) |
| 7338 | { |
| 7339 | if (!target_is_non_stop_p ()) |
| 7340 | { |
| 7341 | /* If any thread is blocked on some internal breakpoint, and we |
| 7342 | simply need to step over that breakpoint to get it going |
| 7343 | again, do that first. */ |
| 7344 | |
| 7345 | /* However, if we see an event for the stepping thread, then we |
| 7346 | know all other threads have been moved past their breakpoints |
| 7347 | already. Let the caller check whether the step is finished, |
| 7348 | etc., before deciding to move it past a breakpoint. */ |
| 7349 | if (ecs->event_thread->control.step_range_end != 0) |
| 7350 | return false; |
| 7351 | |
| 7352 | /* Check if the current thread is blocked on an incomplete |
| 7353 | step-over, interrupted by a random signal. */ |
| 7354 | if (ecs->event_thread->control.trap_expected |
| 7355 | && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP) |
| 7356 | { |
| 7357 | infrun_debug_printf |
| 7358 | ("need to finish step-over of [%s]", |
| 7359 | target_pid_to_str (ecs->event_thread->ptid).c_str ()); |
| 7360 | keep_going (ecs); |
| 7361 | return true; |
| 7362 | } |
| 7363 | |
| 7364 | /* Check if the current thread is blocked by a single-step |
| 7365 | breakpoint of another thread. */ |
| 7366 | if (ecs->hit_singlestep_breakpoint) |
| 7367 | { |
| 7368 | infrun_debug_printf ("need to step [%s] over single-step breakpoint", |
| 7369 | target_pid_to_str (ecs->ptid).c_str ()); |
| 7370 | keep_going (ecs); |
| 7371 | return true; |
| 7372 | } |
| 7373 | |
| 7374 | /* If this thread needs yet another step-over (e.g., stepping |
| 7375 | through a delay slot), do it first before moving on to |
| 7376 | another thread. */ |
| 7377 | if (thread_still_needs_step_over (ecs->event_thread)) |
| 7378 | { |
| 7379 | infrun_debug_printf |
| 7380 | ("thread [%s] still needs step-over", |
| 7381 | target_pid_to_str (ecs->event_thread->ptid).c_str ()); |
| 7382 | keep_going (ecs); |
| 7383 | return true; |
| 7384 | } |
| 7385 | |
| 7386 | /* If scheduler locking applies even if not stepping, there's no |
| 7387 | need to walk over threads. Above we've checked whether the |
| 7388 | current thread is stepping. If some other thread not the |
| 7389 | event thread is stepping, then it must be that scheduler |
| 7390 | locking is not in effect. */ |
| 7391 | if (schedlock_applies (ecs->event_thread)) |
| 7392 | return false; |
| 7393 | |
| 7394 | /* Otherwise, we no longer expect a trap in the current thread. |
| 7395 | Clear the trap_expected flag before switching back -- this is |
| 7396 | what keep_going does as well, if we call it. */ |
| 7397 | ecs->event_thread->control.trap_expected = 0; |
| 7398 | |
| 7399 | /* Likewise, clear the signal if it should not be passed. */ |
| 7400 | if (!signal_program[ecs->event_thread->suspend.stop_signal]) |
| 7401 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 7402 | |
| 7403 | if (restart_stepped_thread (ecs->target, ecs->ptid)) |
| 7404 | { |
| 7405 | prepare_to_wait (ecs); |
| 7406 | return true; |
| 7407 | } |
| 7408 | |
| 7409 | switch_to_thread (ecs->event_thread); |
| 7410 | } |
| 7411 | |
| 7412 | return false; |
| 7413 | } |
| 7414 | |
| 7415 | /* Look for the thread that was stepping, and resume it. |
| 7416 | RESUME_TARGET / RESUME_PTID indicate the set of threads the caller |
| 7417 | is resuming. Return true if a thread was started, false |
| 7418 | otherwise. */ |
| 7419 | |
| 7420 | static bool |
| 7421 | restart_stepped_thread (process_stratum_target *resume_target, |
| 7422 | ptid_t resume_ptid) |
| 7423 | { |
| 7424 | /* Do all pending step-overs before actually proceeding with |
| 7425 | step/next/etc. */ |
| 7426 | if (start_step_over ()) |
| 7427 | return true; |
| 7428 | |
| 7429 | for (thread_info *tp : all_threads_safe ()) |
| 7430 | { |
| 7431 | if (tp->state == THREAD_EXITED) |
| 7432 | continue; |
| 7433 | |
| 7434 | if (tp->suspend.waitstatus_pending_p) |
| 7435 | continue; |
| 7436 | |
| 7437 | /* Ignore threads of processes the caller is not |
| 7438 | resuming. */ |
| 7439 | if (!sched_multi |
| 7440 | && (tp->inf->process_target () != resume_target |
| 7441 | || tp->inf->pid != resume_ptid.pid ())) |
| 7442 | continue; |
| 7443 | |
| 7444 | if (tp->control.trap_expected) |
| 7445 | { |
| 7446 | infrun_debug_printf ("switching back to stepped thread (step-over)"); |
| 7447 | |
| 7448 | if (keep_going_stepped_thread (tp)) |
| 7449 | return true; |
| 7450 | } |
| 7451 | } |
| 7452 | |
| 7453 | for (thread_info *tp : all_threads_safe ()) |
| 7454 | { |
| 7455 | if (tp->state == THREAD_EXITED) |
| 7456 | continue; |
| 7457 | |
| 7458 | if (tp->suspend.waitstatus_pending_p) |
| 7459 | continue; |
| 7460 | |
| 7461 | /* Ignore threads of processes the caller is not |
| 7462 | resuming. */ |
| 7463 | if (!sched_multi |
| 7464 | && (tp->inf->process_target () != resume_target |
| 7465 | || tp->inf->pid != resume_ptid.pid ())) |
| 7466 | continue; |
| 7467 | |
| 7468 | /* Did we find the stepping thread? */ |
| 7469 | if (tp->control.step_range_end) |
| 7470 | { |
| 7471 | infrun_debug_printf ("switching back to stepped thread (stepping)"); |
| 7472 | |
| 7473 | if (keep_going_stepped_thread (tp)) |
| 7474 | return true; |
| 7475 | } |
| 7476 | } |
| 7477 | |
| 7478 | return false; |
| 7479 | } |
| 7480 | |
| 7481 | /* See infrun.h. */ |
| 7482 | |
| 7483 | void |
| 7484 | restart_after_all_stop_detach (process_stratum_target *proc_target) |
| 7485 | { |
| 7486 | /* Note we don't check target_is_non_stop_p() here, because the |
| 7487 | current inferior may no longer have a process_stratum target |
| 7488 | pushed, as we just detached. */ |
| 7489 | |
| 7490 | /* See if we have a THREAD_RUNNING thread that need to be |
| 7491 | re-resumed. If we have any thread that is already executing, |
| 7492 | then we don't need to resume the target -- it is already been |
| 7493 | resumed. With the remote target (in all-stop), it's even |
| 7494 | impossible to issue another resumption if the target is already |
| 7495 | resumed, until the target reports a stop. */ |
| 7496 | for (thread_info *thr : all_threads (proc_target)) |
| 7497 | { |
| 7498 | if (thr->state != THREAD_RUNNING) |
| 7499 | continue; |
| 7500 | |
| 7501 | /* If we have any thread that is already executing, then we |
| 7502 | don't need to resume the target -- it is already been |
| 7503 | resumed. */ |
| 7504 | if (thr->executing) |
| 7505 | return; |
| 7506 | |
| 7507 | /* If we have a pending event to process, skip resuming the |
| 7508 | target and go straight to processing it. */ |
| 7509 | if (thr->resumed && thr->suspend.waitstatus_pending_p) |
| 7510 | return; |
| 7511 | } |
| 7512 | |
| 7513 | /* Alright, we need to re-resume the target. If a thread was |
| 7514 | stepping, we need to restart it stepping. */ |
| 7515 | if (restart_stepped_thread (proc_target, minus_one_ptid)) |
| 7516 | return; |
| 7517 | |
| 7518 | /* Otherwise, find the first THREAD_RUNNING thread and resume |
| 7519 | it. */ |
| 7520 | for (thread_info *thr : all_threads (proc_target)) |
| 7521 | { |
| 7522 | if (thr->state != THREAD_RUNNING) |
| 7523 | continue; |
| 7524 | |
| 7525 | execution_control_state ecs; |
| 7526 | reset_ecs (&ecs, thr); |
| 7527 | switch_to_thread (thr); |
| 7528 | keep_going (&ecs); |
| 7529 | return; |
| 7530 | } |
| 7531 | } |
| 7532 | |
| 7533 | /* Set a previously stepped thread back to stepping. Returns true on |
| 7534 | success, false if the resume is not possible (e.g., the thread |
| 7535 | vanished). */ |
| 7536 | |
| 7537 | static bool |
| 7538 | keep_going_stepped_thread (struct thread_info *tp) |
| 7539 | { |
| 7540 | struct frame_info *frame; |
| 7541 | struct execution_control_state ecss; |
| 7542 | struct execution_control_state *ecs = &ecss; |
| 7543 | |
| 7544 | /* If the stepping thread exited, then don't try to switch back and |
| 7545 | resume it, which could fail in several different ways depending |
| 7546 | on the target. Instead, just keep going. |
| 7547 | |
| 7548 | We can find a stepping dead thread in the thread list in two |
| 7549 | cases: |
| 7550 | |
| 7551 | - The target supports thread exit events, and when the target |
| 7552 | tries to delete the thread from the thread list, inferior_ptid |
| 7553 | pointed at the exiting thread. In such case, calling |
| 7554 | delete_thread does not really remove the thread from the list; |
| 7555 | instead, the thread is left listed, with 'exited' state. |
| 7556 | |
| 7557 | - The target's debug interface does not support thread exit |
| 7558 | events, and so we have no idea whatsoever if the previously |
| 7559 | stepping thread is still alive. For that reason, we need to |
| 7560 | synchronously query the target now. */ |
| 7561 | |
| 7562 | if (tp->state == THREAD_EXITED || !target_thread_alive (tp->ptid)) |
| 7563 | { |
| 7564 | infrun_debug_printf ("not resuming previously stepped thread, it has " |
| 7565 | "vanished"); |
| 7566 | |
| 7567 | delete_thread (tp); |
| 7568 | return false; |
| 7569 | } |
| 7570 | |
| 7571 | infrun_debug_printf ("resuming previously stepped thread"); |
| 7572 | |
| 7573 | reset_ecs (ecs, tp); |
| 7574 | switch_to_thread (tp); |
| 7575 | |
| 7576 | tp->suspend.stop_pc = regcache_read_pc (get_thread_regcache (tp)); |
| 7577 | frame = get_current_frame (); |
| 7578 | |
| 7579 | /* If the PC of the thread we were trying to single-step has |
| 7580 | changed, then that thread has trapped or been signaled, but the |
| 7581 | event has not been reported to GDB yet. Re-poll the target |
| 7582 | looking for this particular thread's event (i.e. temporarily |
| 7583 | enable schedlock) by: |
| 7584 | |
| 7585 | - setting a break at the current PC |
| 7586 | - resuming that particular thread, only (by setting trap |
| 7587 | expected) |
| 7588 | |
| 7589 | This prevents us continuously moving the single-step breakpoint |
| 7590 | forward, one instruction at a time, overstepping. */ |
| 7591 | |
| 7592 | if (tp->suspend.stop_pc != tp->prev_pc) |
| 7593 | { |
| 7594 | ptid_t resume_ptid; |
| 7595 | |
| 7596 | infrun_debug_printf ("expected thread advanced also (%s -> %s)", |
| 7597 | paddress (target_gdbarch (), tp->prev_pc), |
| 7598 | paddress (target_gdbarch (), tp->suspend.stop_pc)); |
| 7599 | |
| 7600 | /* Clear the info of the previous step-over, as it's no longer |
| 7601 | valid (if the thread was trying to step over a breakpoint, it |
| 7602 | has already succeeded). It's what keep_going would do too, |
| 7603 | if we called it. Do this before trying to insert the sss |
| 7604 | breakpoint, otherwise if we were previously trying to step |
| 7605 | over this exact address in another thread, the breakpoint is |
| 7606 | skipped. */ |
| 7607 | clear_step_over_info (); |
| 7608 | tp->control.trap_expected = 0; |
| 7609 | |
| 7610 | insert_single_step_breakpoint (get_frame_arch (frame), |
| 7611 | get_frame_address_space (frame), |
| 7612 | tp->suspend.stop_pc); |
| 7613 | |
| 7614 | tp->resumed = true; |
| 7615 | resume_ptid = internal_resume_ptid (tp->control.stepping_command); |
| 7616 | do_target_resume (resume_ptid, false, GDB_SIGNAL_0); |
| 7617 | } |
| 7618 | else |
| 7619 | { |
| 7620 | infrun_debug_printf ("expected thread still hasn't advanced"); |
| 7621 | |
| 7622 | keep_going_pass_signal (ecs); |
| 7623 | } |
| 7624 | |
| 7625 | return true; |
| 7626 | } |
| 7627 | |
| 7628 | /* Is thread TP in the middle of (software or hardware) |
| 7629 | single-stepping? (Note the result of this function must never be |
| 7630 | passed directly as target_resume's STEP parameter.) */ |
| 7631 | |
| 7632 | static bool |
| 7633 | currently_stepping (struct thread_info *tp) |
| 7634 | { |
| 7635 | return ((tp->control.step_range_end |
| 7636 | && tp->control.step_resume_breakpoint == NULL) |
| 7637 | || tp->control.trap_expected |
| 7638 | || tp->stepped_breakpoint |
| 7639 | || bpstat_should_step ()); |
| 7640 | } |
| 7641 | |
| 7642 | /* Inferior has stepped into a subroutine call with source code that |
| 7643 | we should not step over. Do step to the first line of code in |
| 7644 | it. */ |
| 7645 | |
| 7646 | static void |
| 7647 | handle_step_into_function (struct gdbarch *gdbarch, |
| 7648 | struct execution_control_state *ecs) |
| 7649 | { |
| 7650 | fill_in_stop_func (gdbarch, ecs); |
| 7651 | |
| 7652 | compunit_symtab *cust |
| 7653 | = find_pc_compunit_symtab (ecs->event_thread->suspend.stop_pc); |
| 7654 | if (cust != NULL && compunit_language (cust) != language_asm) |
| 7655 | ecs->stop_func_start |
| 7656 | = gdbarch_skip_prologue_noexcept (gdbarch, ecs->stop_func_start); |
| 7657 | |
| 7658 | symtab_and_line stop_func_sal = find_pc_line (ecs->stop_func_start, 0); |
| 7659 | /* Use the step_resume_break to step until the end of the prologue, |
| 7660 | even if that involves jumps (as it seems to on the vax under |
| 7661 | 4.2). */ |
| 7662 | /* If the prologue ends in the middle of a source line, continue to |
| 7663 | the end of that source line (if it is still within the function). |
| 7664 | Otherwise, just go to end of prologue. */ |
| 7665 | if (stop_func_sal.end |
| 7666 | && stop_func_sal.pc != ecs->stop_func_start |
| 7667 | && stop_func_sal.end < ecs->stop_func_end) |
| 7668 | ecs->stop_func_start = stop_func_sal.end; |
| 7669 | |
| 7670 | /* Architectures which require breakpoint adjustment might not be able |
| 7671 | to place a breakpoint at the computed address. If so, the test |
| 7672 | ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust |
| 7673 | ecs->stop_func_start to an address at which a breakpoint may be |
| 7674 | legitimately placed. |
| 7675 | |
| 7676 | Note: kevinb/2004-01-19: On FR-V, if this adjustment is not |
| 7677 | made, GDB will enter an infinite loop when stepping through |
| 7678 | optimized code consisting of VLIW instructions which contain |
| 7679 | subinstructions corresponding to different source lines. On |
| 7680 | FR-V, it's not permitted to place a breakpoint on any but the |
| 7681 | first subinstruction of a VLIW instruction. When a breakpoint is |
| 7682 | set, GDB will adjust the breakpoint address to the beginning of |
| 7683 | the VLIW instruction. Thus, we need to make the corresponding |
| 7684 | adjustment here when computing the stop address. */ |
| 7685 | |
| 7686 | if (gdbarch_adjust_breakpoint_address_p (gdbarch)) |
| 7687 | { |
| 7688 | ecs->stop_func_start |
| 7689 | = gdbarch_adjust_breakpoint_address (gdbarch, |
| 7690 | ecs->stop_func_start); |
| 7691 | } |
| 7692 | |
| 7693 | if (ecs->stop_func_start == ecs->event_thread->suspend.stop_pc) |
| 7694 | { |
| 7695 | /* We are already there: stop now. */ |
| 7696 | end_stepping_range (ecs); |
| 7697 | return; |
| 7698 | } |
| 7699 | else |
| 7700 | { |
| 7701 | /* Put the step-breakpoint there and go until there. */ |
| 7702 | symtab_and_line sr_sal; |
| 7703 | sr_sal.pc = ecs->stop_func_start; |
| 7704 | sr_sal.section = find_pc_overlay (ecs->stop_func_start); |
| 7705 | sr_sal.pspace = get_frame_program_space (get_current_frame ()); |
| 7706 | |
| 7707 | /* Do not specify what the fp should be when we stop since on |
| 7708 | some machines the prologue is where the new fp value is |
| 7709 | established. */ |
| 7710 | insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal, null_frame_id); |
| 7711 | |
| 7712 | /* And make sure stepping stops right away then. */ |
| 7713 | ecs->event_thread->control.step_range_end |
| 7714 | = ecs->event_thread->control.step_range_start; |
| 7715 | } |
| 7716 | keep_going (ecs); |
| 7717 | } |
| 7718 | |
| 7719 | /* Inferior has stepped backward into a subroutine call with source |
| 7720 | code that we should not step over. Do step to the beginning of the |
| 7721 | last line of code in it. */ |
| 7722 | |
| 7723 | static void |
| 7724 | handle_step_into_function_backward (struct gdbarch *gdbarch, |
| 7725 | struct execution_control_state *ecs) |
| 7726 | { |
| 7727 | struct compunit_symtab *cust; |
| 7728 | struct symtab_and_line stop_func_sal; |
| 7729 | |
| 7730 | fill_in_stop_func (gdbarch, ecs); |
| 7731 | |
| 7732 | cust = find_pc_compunit_symtab (ecs->event_thread->suspend.stop_pc); |
| 7733 | if (cust != NULL && compunit_language (cust) != language_asm) |
| 7734 | ecs->stop_func_start |
| 7735 | = gdbarch_skip_prologue_noexcept (gdbarch, ecs->stop_func_start); |
| 7736 | |
| 7737 | stop_func_sal = find_pc_line (ecs->event_thread->suspend.stop_pc, 0); |
| 7738 | |
| 7739 | /* OK, we're just going to keep stepping here. */ |
| 7740 | if (stop_func_sal.pc == ecs->event_thread->suspend.stop_pc) |
| 7741 | { |
| 7742 | /* We're there already. Just stop stepping now. */ |
| 7743 | end_stepping_range (ecs); |
| 7744 | } |
| 7745 | else |
| 7746 | { |
| 7747 | /* Else just reset the step range and keep going. |
| 7748 | No step-resume breakpoint, they don't work for |
| 7749 | epilogues, which can have multiple entry paths. */ |
| 7750 | ecs->event_thread->control.step_range_start = stop_func_sal.pc; |
| 7751 | ecs->event_thread->control.step_range_end = stop_func_sal.end; |
| 7752 | keep_going (ecs); |
| 7753 | } |
| 7754 | return; |
| 7755 | } |
| 7756 | |
| 7757 | /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID. |
| 7758 | This is used to both functions and to skip over code. */ |
| 7759 | |
| 7760 | static void |
| 7761 | insert_step_resume_breakpoint_at_sal_1 (struct gdbarch *gdbarch, |
| 7762 | struct symtab_and_line sr_sal, |
| 7763 | struct frame_id sr_id, |
| 7764 | enum bptype sr_type) |
| 7765 | { |
| 7766 | /* There should never be more than one step-resume or longjmp-resume |
| 7767 | breakpoint per thread, so we should never be setting a new |
| 7768 | step_resume_breakpoint when one is already active. */ |
| 7769 | gdb_assert (inferior_thread ()->control.step_resume_breakpoint == NULL); |
| 7770 | gdb_assert (sr_type == bp_step_resume || sr_type == bp_hp_step_resume); |
| 7771 | |
| 7772 | infrun_debug_printf ("inserting step-resume breakpoint at %s", |
| 7773 | paddress (gdbarch, sr_sal.pc)); |
| 7774 | |
| 7775 | inferior_thread ()->control.step_resume_breakpoint |
| 7776 | = set_momentary_breakpoint (gdbarch, sr_sal, sr_id, sr_type).release (); |
| 7777 | } |
| 7778 | |
| 7779 | void |
| 7780 | insert_step_resume_breakpoint_at_sal (struct gdbarch *gdbarch, |
| 7781 | struct symtab_and_line sr_sal, |
| 7782 | struct frame_id sr_id) |
| 7783 | { |
| 7784 | insert_step_resume_breakpoint_at_sal_1 (gdbarch, |
| 7785 | sr_sal, sr_id, |
| 7786 | bp_step_resume); |
| 7787 | } |
| 7788 | |
| 7789 | /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc. |
| 7790 | This is used to skip a potential signal handler. |
| 7791 | |
| 7792 | This is called with the interrupted function's frame. The signal |
| 7793 | handler, when it returns, will resume the interrupted function at |
| 7794 | RETURN_FRAME.pc. */ |
| 7795 | |
| 7796 | static void |
| 7797 | insert_hp_step_resume_breakpoint_at_frame (struct frame_info *return_frame) |
| 7798 | { |
| 7799 | gdb_assert (return_frame != NULL); |
| 7800 | |
| 7801 | struct gdbarch *gdbarch = get_frame_arch (return_frame); |
| 7802 | |
| 7803 | symtab_and_line sr_sal; |
| 7804 | sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, get_frame_pc (return_frame)); |
| 7805 | sr_sal.section = find_pc_overlay (sr_sal.pc); |
| 7806 | sr_sal.pspace = get_frame_program_space (return_frame); |
| 7807 | |
| 7808 | insert_step_resume_breakpoint_at_sal_1 (gdbarch, sr_sal, |
| 7809 | get_stack_frame_id (return_frame), |
| 7810 | bp_hp_step_resume); |
| 7811 | } |
| 7812 | |
| 7813 | /* Insert a "step-resume breakpoint" at the previous frame's PC. This |
| 7814 | is used to skip a function after stepping into it (for "next" or if |
| 7815 | the called function has no debugging information). |
| 7816 | |
| 7817 | The current function has almost always been reached by single |
| 7818 | stepping a call or return instruction. NEXT_FRAME belongs to the |
| 7819 | current function, and the breakpoint will be set at the caller's |
| 7820 | resume address. |
| 7821 | |
| 7822 | This is a separate function rather than reusing |
| 7823 | insert_hp_step_resume_breakpoint_at_frame in order to avoid |
| 7824 | get_prev_frame, which may stop prematurely (see the implementation |
| 7825 | of frame_unwind_caller_id for an example). */ |
| 7826 | |
| 7827 | static void |
| 7828 | insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame) |
| 7829 | { |
| 7830 | /* We shouldn't have gotten here if we don't know where the call site |
| 7831 | is. */ |
| 7832 | gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame))); |
| 7833 | |
| 7834 | struct gdbarch *gdbarch = frame_unwind_caller_arch (next_frame); |
| 7835 | |
| 7836 | symtab_and_line sr_sal; |
| 7837 | sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, |
| 7838 | frame_unwind_caller_pc (next_frame)); |
| 7839 | sr_sal.section = find_pc_overlay (sr_sal.pc); |
| 7840 | sr_sal.pspace = frame_unwind_program_space (next_frame); |
| 7841 | |
| 7842 | insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal, |
| 7843 | frame_unwind_caller_id (next_frame)); |
| 7844 | } |
| 7845 | |
| 7846 | /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a |
| 7847 | new breakpoint at the target of a jmp_buf. The handling of |
| 7848 | longjmp-resume uses the same mechanisms used for handling |
| 7849 | "step-resume" breakpoints. */ |
| 7850 | |
| 7851 | static void |
| 7852 | insert_longjmp_resume_breakpoint (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 7853 | { |
| 7854 | /* There should never be more than one longjmp-resume breakpoint per |
| 7855 | thread, so we should never be setting a new |
| 7856 | longjmp_resume_breakpoint when one is already active. */ |
| 7857 | gdb_assert (inferior_thread ()->control.exception_resume_breakpoint == NULL); |
| 7858 | |
| 7859 | infrun_debug_printf ("inserting longjmp-resume breakpoint at %s", |
| 7860 | paddress (gdbarch, pc)); |
| 7861 | |
| 7862 | inferior_thread ()->control.exception_resume_breakpoint = |
| 7863 | set_momentary_breakpoint_at_pc (gdbarch, pc, bp_longjmp_resume).release (); |
| 7864 | } |
| 7865 | |
| 7866 | /* Insert an exception resume breakpoint. TP is the thread throwing |
| 7867 | the exception. The block B is the block of the unwinder debug hook |
| 7868 | function. FRAME is the frame corresponding to the call to this |
| 7869 | function. SYM is the symbol of the function argument holding the |
| 7870 | target PC of the exception. */ |
| 7871 | |
| 7872 | static void |
| 7873 | insert_exception_resume_breakpoint (struct thread_info *tp, |
| 7874 | const struct block *b, |
| 7875 | struct frame_info *frame, |
| 7876 | struct symbol *sym) |
| 7877 | { |
| 7878 | try |
| 7879 | { |
| 7880 | struct block_symbol vsym; |
| 7881 | struct value *value; |
| 7882 | CORE_ADDR handler; |
| 7883 | struct breakpoint *bp; |
| 7884 | |
| 7885 | vsym = lookup_symbol_search_name (sym->search_name (), |
| 7886 | b, VAR_DOMAIN); |
| 7887 | value = read_var_value (vsym.symbol, vsym.block, frame); |
| 7888 | /* If the value was optimized out, revert to the old behavior. */ |
| 7889 | if (! value_optimized_out (value)) |
| 7890 | { |
| 7891 | handler = value_as_address (value); |
| 7892 | |
| 7893 | infrun_debug_printf ("exception resume at %lx", |
| 7894 | (unsigned long) handler); |
| 7895 | |
| 7896 | bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame), |
| 7897 | handler, |
| 7898 | bp_exception_resume).release (); |
| 7899 | |
| 7900 | /* set_momentary_breakpoint_at_pc invalidates FRAME. */ |
| 7901 | frame = NULL; |
| 7902 | |
| 7903 | bp->thread = tp->global_num; |
| 7904 | inferior_thread ()->control.exception_resume_breakpoint = bp; |
| 7905 | } |
| 7906 | } |
| 7907 | catch (const gdb_exception_error &e) |
| 7908 | { |
| 7909 | /* We want to ignore errors here. */ |
| 7910 | } |
| 7911 | } |
| 7912 | |
| 7913 | /* A helper for check_exception_resume that sets an |
| 7914 | exception-breakpoint based on a SystemTap probe. */ |
| 7915 | |
| 7916 | static void |
| 7917 | insert_exception_resume_from_probe (struct thread_info *tp, |
| 7918 | const struct bound_probe *probe, |
| 7919 | struct frame_info *frame) |
| 7920 | { |
| 7921 | struct value *arg_value; |
| 7922 | CORE_ADDR handler; |
| 7923 | struct breakpoint *bp; |
| 7924 | |
| 7925 | arg_value = probe_safe_evaluate_at_pc (frame, 1); |
| 7926 | if (!arg_value) |
| 7927 | return; |
| 7928 | |
| 7929 | handler = value_as_address (arg_value); |
| 7930 | |
| 7931 | infrun_debug_printf ("exception resume at %s", |
| 7932 | paddress (probe->objfile->arch (), handler)); |
| 7933 | |
| 7934 | bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame), |
| 7935 | handler, bp_exception_resume).release (); |
| 7936 | bp->thread = tp->global_num; |
| 7937 | inferior_thread ()->control.exception_resume_breakpoint = bp; |
| 7938 | } |
| 7939 | |
| 7940 | /* This is called when an exception has been intercepted. Check to |
| 7941 | see whether the exception's destination is of interest, and if so, |
| 7942 | set an exception resume breakpoint there. */ |
| 7943 | |
| 7944 | static void |
| 7945 | check_exception_resume (struct execution_control_state *ecs, |
| 7946 | struct frame_info *frame) |
| 7947 | { |
| 7948 | struct bound_probe probe; |
| 7949 | struct symbol *func; |
| 7950 | |
| 7951 | /* First see if this exception unwinding breakpoint was set via a |
| 7952 | SystemTap probe point. If so, the probe has two arguments: the |
| 7953 | CFA and the HANDLER. We ignore the CFA, extract the handler, and |
| 7954 | set a breakpoint there. */ |
| 7955 | probe = find_probe_by_pc (get_frame_pc (frame)); |
| 7956 | if (probe.prob) |
| 7957 | { |
| 7958 | insert_exception_resume_from_probe (ecs->event_thread, &probe, frame); |
| 7959 | return; |
| 7960 | } |
| 7961 | |
| 7962 | func = get_frame_function (frame); |
| 7963 | if (!func) |
| 7964 | return; |
| 7965 | |
| 7966 | try |
| 7967 | { |
| 7968 | const struct block *b; |
| 7969 | struct block_iterator iter; |
| 7970 | struct symbol *sym; |
| 7971 | int argno = 0; |
| 7972 | |
| 7973 | /* The exception breakpoint is a thread-specific breakpoint on |
| 7974 | the unwinder's debug hook, declared as: |
| 7975 | |
| 7976 | void _Unwind_DebugHook (void *cfa, void *handler); |
| 7977 | |
| 7978 | The CFA argument indicates the frame to which control is |
| 7979 | about to be transferred. HANDLER is the destination PC. |
| 7980 | |
| 7981 | We ignore the CFA and set a temporary breakpoint at HANDLER. |
| 7982 | This is not extremely efficient but it avoids issues in gdb |
| 7983 | with computing the DWARF CFA, and it also works even in weird |
| 7984 | cases such as throwing an exception from inside a signal |
| 7985 | handler. */ |
| 7986 | |
| 7987 | b = SYMBOL_BLOCK_VALUE (func); |
| 7988 | ALL_BLOCK_SYMBOLS (b, iter, sym) |
| 7989 | { |
| 7990 | if (!SYMBOL_IS_ARGUMENT (sym)) |
| 7991 | continue; |
| 7992 | |
| 7993 | if (argno == 0) |
| 7994 | ++argno; |
| 7995 | else |
| 7996 | { |
| 7997 | insert_exception_resume_breakpoint (ecs->event_thread, |
| 7998 | b, frame, sym); |
| 7999 | break; |
| 8000 | } |
| 8001 | } |
| 8002 | } |
| 8003 | catch (const gdb_exception_error &e) |
| 8004 | { |
| 8005 | } |
| 8006 | } |
| 8007 | |
| 8008 | static void |
| 8009 | stop_waiting (struct execution_control_state *ecs) |
| 8010 | { |
| 8011 | infrun_debug_printf ("stop_waiting"); |
| 8012 | |
| 8013 | /* Let callers know we don't want to wait for the inferior anymore. */ |
| 8014 | ecs->wait_some_more = 0; |
| 8015 | |
| 8016 | /* If all-stop, but there exists a non-stop target, stop all |
| 8017 | threads now that we're presenting the stop to the user. */ |
| 8018 | if (!non_stop && exists_non_stop_target ()) |
| 8019 | stop_all_threads (); |
| 8020 | } |
| 8021 | |
| 8022 | /* Like keep_going, but passes the signal to the inferior, even if the |
| 8023 | signal is set to nopass. */ |
| 8024 | |
| 8025 | static void |
| 8026 | keep_going_pass_signal (struct execution_control_state *ecs) |
| 8027 | { |
| 8028 | gdb_assert (ecs->event_thread->ptid == inferior_ptid); |
| 8029 | gdb_assert (!ecs->event_thread->resumed); |
| 8030 | |
| 8031 | /* Save the pc before execution, to compare with pc after stop. */ |
| 8032 | ecs->event_thread->prev_pc |
| 8033 | = regcache_read_pc_protected (get_thread_regcache (ecs->event_thread)); |
| 8034 | |
| 8035 | if (ecs->event_thread->control.trap_expected) |
| 8036 | { |
| 8037 | struct thread_info *tp = ecs->event_thread; |
| 8038 | |
| 8039 | infrun_debug_printf ("%s has trap_expected set, " |
| 8040 | "resuming to collect trap", |
| 8041 | target_pid_to_str (tp->ptid).c_str ()); |
| 8042 | |
| 8043 | /* We haven't yet gotten our trap, and either: intercepted a |
| 8044 | non-signal event (e.g., a fork); or took a signal which we |
| 8045 | are supposed to pass through to the inferior. Simply |
| 8046 | continue. */ |
| 8047 | resume (ecs->event_thread->suspend.stop_signal); |
| 8048 | } |
| 8049 | else if (step_over_info_valid_p ()) |
| 8050 | { |
| 8051 | /* Another thread is stepping over a breakpoint in-line. If |
| 8052 | this thread needs a step-over too, queue the request. In |
| 8053 | either case, this resume must be deferred for later. */ |
| 8054 | struct thread_info *tp = ecs->event_thread; |
| 8055 | |
| 8056 | if (ecs->hit_singlestep_breakpoint |
| 8057 | || thread_still_needs_step_over (tp)) |
| 8058 | { |
| 8059 | infrun_debug_printf ("step-over already in progress: " |
| 8060 | "step-over for %s deferred", |
| 8061 | target_pid_to_str (tp->ptid).c_str ()); |
| 8062 | global_thread_step_over_chain_enqueue (tp); |
| 8063 | } |
| 8064 | else |
| 8065 | { |
| 8066 | infrun_debug_printf ("step-over in progress: resume of %s deferred", |
| 8067 | target_pid_to_str (tp->ptid).c_str ()); |
| 8068 | } |
| 8069 | } |
| 8070 | else |
| 8071 | { |
| 8072 | struct regcache *regcache = get_current_regcache (); |
| 8073 | int remove_bp; |
| 8074 | int remove_wps; |
| 8075 | step_over_what step_what; |
| 8076 | |
| 8077 | /* Either the trap was not expected, but we are continuing |
| 8078 | anyway (if we got a signal, the user asked it be passed to |
| 8079 | the child) |
| 8080 | -- or -- |
| 8081 | We got our expected trap, but decided we should resume from |
| 8082 | it. |
| 8083 | |
| 8084 | We're going to run this baby now! |
| 8085 | |
| 8086 | Note that insert_breakpoints won't try to re-insert |
| 8087 | already inserted breakpoints. Therefore, we don't |
| 8088 | care if breakpoints were already inserted, or not. */ |
| 8089 | |
| 8090 | /* If we need to step over a breakpoint, and we're not using |
| 8091 | displaced stepping to do so, insert all breakpoints |
| 8092 | (watchpoints, etc.) but the one we're stepping over, step one |
| 8093 | instruction, and then re-insert the breakpoint when that step |
| 8094 | is finished. */ |
| 8095 | |
| 8096 | step_what = thread_still_needs_step_over (ecs->event_thread); |
| 8097 | |
| 8098 | remove_bp = (ecs->hit_singlestep_breakpoint |
| 8099 | || (step_what & STEP_OVER_BREAKPOINT)); |
| 8100 | remove_wps = (step_what & STEP_OVER_WATCHPOINT); |
| 8101 | |
| 8102 | /* We can't use displaced stepping if we need to step past a |
| 8103 | watchpoint. The instruction copied to the scratch pad would |
| 8104 | still trigger the watchpoint. */ |
| 8105 | if (remove_bp |
| 8106 | && (remove_wps || !use_displaced_stepping (ecs->event_thread))) |
| 8107 | { |
| 8108 | set_step_over_info (regcache->aspace (), |
| 8109 | regcache_read_pc (regcache), remove_wps, |
| 8110 | ecs->event_thread->global_num); |
| 8111 | } |
| 8112 | else if (remove_wps) |
| 8113 | set_step_over_info (NULL, 0, remove_wps, -1); |
| 8114 | |
| 8115 | /* If we now need to do an in-line step-over, we need to stop |
| 8116 | all other threads. Note this must be done before |
| 8117 | insert_breakpoints below, because that removes the breakpoint |
| 8118 | we're about to step over, otherwise other threads could miss |
| 8119 | it. */ |
| 8120 | if (step_over_info_valid_p () && target_is_non_stop_p ()) |
| 8121 | stop_all_threads (); |
| 8122 | |
| 8123 | /* Stop stepping if inserting breakpoints fails. */ |
| 8124 | try |
| 8125 | { |
| 8126 | insert_breakpoints (); |
| 8127 | } |
| 8128 | catch (const gdb_exception_error &e) |
| 8129 | { |
| 8130 | exception_print (gdb_stderr, e); |
| 8131 | stop_waiting (ecs); |
| 8132 | clear_step_over_info (); |
| 8133 | return; |
| 8134 | } |
| 8135 | |
| 8136 | ecs->event_thread->control.trap_expected = (remove_bp || remove_wps); |
| 8137 | |
| 8138 | resume (ecs->event_thread->suspend.stop_signal); |
| 8139 | } |
| 8140 | |
| 8141 | prepare_to_wait (ecs); |
| 8142 | } |
| 8143 | |
| 8144 | /* Called when we should continue running the inferior, because the |
| 8145 | current event doesn't cause a user visible stop. This does the |
| 8146 | resuming part; waiting for the next event is done elsewhere. */ |
| 8147 | |
| 8148 | static void |
| 8149 | keep_going (struct execution_control_state *ecs) |
| 8150 | { |
| 8151 | if (ecs->event_thread->control.trap_expected |
| 8152 | && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP) |
| 8153 | ecs->event_thread->control.trap_expected = 0; |
| 8154 | |
| 8155 | if (!signal_program[ecs->event_thread->suspend.stop_signal]) |
| 8156 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 8157 | keep_going_pass_signal (ecs); |
| 8158 | } |
| 8159 | |
| 8160 | /* This function normally comes after a resume, before |
| 8161 | handle_inferior_event exits. It takes care of any last bits of |
| 8162 | housekeeping, and sets the all-important wait_some_more flag. */ |
| 8163 | |
| 8164 | static void |
| 8165 | prepare_to_wait (struct execution_control_state *ecs) |
| 8166 | { |
| 8167 | infrun_debug_printf ("prepare_to_wait"); |
| 8168 | |
| 8169 | ecs->wait_some_more = 1; |
| 8170 | |
| 8171 | /* If the target can't async, emulate it by marking the infrun event |
| 8172 | handler such that as soon as we get back to the event-loop, we |
| 8173 | immediately end up in fetch_inferior_event again calling |
| 8174 | target_wait. */ |
| 8175 | if (!target_can_async_p ()) |
| 8176 | mark_infrun_async_event_handler (); |
| 8177 | } |
| 8178 | |
| 8179 | /* We are done with the step range of a step/next/si/ni command. |
| 8180 | Called once for each n of a "step n" operation. */ |
| 8181 | |
| 8182 | static void |
| 8183 | end_stepping_range (struct execution_control_state *ecs) |
| 8184 | { |
| 8185 | ecs->event_thread->control.stop_step = 1; |
| 8186 | stop_waiting (ecs); |
| 8187 | } |
| 8188 | |
| 8189 | /* Several print_*_reason functions to print why the inferior has stopped. |
| 8190 | We always print something when the inferior exits, or receives a signal. |
| 8191 | The rest of the cases are dealt with later on in normal_stop and |
| 8192 | print_it_typical. Ideally there should be a call to one of these |
| 8193 | print_*_reason functions functions from handle_inferior_event each time |
| 8194 | stop_waiting is called. |
| 8195 | |
| 8196 | Note that we don't call these directly, instead we delegate that to |
| 8197 | the interpreters, through observers. Interpreters then call these |
| 8198 | with whatever uiout is right. */ |
| 8199 | |
| 8200 | void |
| 8201 | print_end_stepping_range_reason (struct ui_out *uiout) |
| 8202 | { |
| 8203 | /* For CLI-like interpreters, print nothing. */ |
| 8204 | |
| 8205 | if (uiout->is_mi_like_p ()) |
| 8206 | { |
| 8207 | uiout->field_string ("reason", |
| 8208 | async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE)); |
| 8209 | } |
| 8210 | } |
| 8211 | |
| 8212 | void |
| 8213 | print_signal_exited_reason (struct ui_out *uiout, enum gdb_signal siggnal) |
| 8214 | { |
| 8215 | annotate_signalled (); |
| 8216 | if (uiout->is_mi_like_p ()) |
| 8217 | uiout->field_string |
| 8218 | ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED)); |
| 8219 | uiout->text ("\nProgram terminated with signal "); |
| 8220 | annotate_signal_name (); |
| 8221 | uiout->field_string ("signal-name", |
| 8222 | gdb_signal_to_name (siggnal)); |
| 8223 | annotate_signal_name_end (); |
| 8224 | uiout->text (", "); |
| 8225 | annotate_signal_string (); |
| 8226 | uiout->field_string ("signal-meaning", |
| 8227 | gdb_signal_to_string (siggnal)); |
| 8228 | annotate_signal_string_end (); |
| 8229 | uiout->text (".\n"); |
| 8230 | uiout->text ("The program no longer exists.\n"); |
| 8231 | } |
| 8232 | |
| 8233 | void |
| 8234 | print_exited_reason (struct ui_out *uiout, int exitstatus) |
| 8235 | { |
| 8236 | struct inferior *inf = current_inferior (); |
| 8237 | std::string pidstr = target_pid_to_str (ptid_t (inf->pid)); |
| 8238 | |
| 8239 | annotate_exited (exitstatus); |
| 8240 | if (exitstatus) |
| 8241 | { |
| 8242 | if (uiout->is_mi_like_p ()) |
| 8243 | uiout->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED)); |
| 8244 | std::string exit_code_str |
| 8245 | = string_printf ("0%o", (unsigned int) exitstatus); |
| 8246 | uiout->message ("[Inferior %s (%s) exited with code %pF]\n", |
| 8247 | plongest (inf->num), pidstr.c_str (), |
| 8248 | string_field ("exit-code", exit_code_str.c_str ())); |
| 8249 | } |
| 8250 | else |
| 8251 | { |
| 8252 | if (uiout->is_mi_like_p ()) |
| 8253 | uiout->field_string |
| 8254 | ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY)); |
| 8255 | uiout->message ("[Inferior %s (%s) exited normally]\n", |
| 8256 | plongest (inf->num), pidstr.c_str ()); |
| 8257 | } |
| 8258 | } |
| 8259 | |
| 8260 | void |
| 8261 | print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal) |
| 8262 | { |
| 8263 | struct thread_info *thr = inferior_thread (); |
| 8264 | |
| 8265 | annotate_signal (); |
| 8266 | |
| 8267 | if (uiout->is_mi_like_p ()) |
| 8268 | ; |
| 8269 | else if (show_thread_that_caused_stop ()) |
| 8270 | { |
| 8271 | const char *name; |
| 8272 | |
| 8273 | uiout->text ("\nThread "); |
| 8274 | uiout->field_string ("thread-id", print_thread_id (thr)); |
| 8275 | |
| 8276 | name = thr->name != NULL ? thr->name : target_thread_name (thr); |
| 8277 | if (name != NULL) |
| 8278 | { |
| 8279 | uiout->text (" \""); |
| 8280 | uiout->field_string ("name", name); |
| 8281 | uiout->text ("\""); |
| 8282 | } |
| 8283 | } |
| 8284 | else |
| 8285 | uiout->text ("\nProgram"); |
| 8286 | |
| 8287 | if (siggnal == GDB_SIGNAL_0 && !uiout->is_mi_like_p ()) |
| 8288 | uiout->text (" stopped"); |
| 8289 | else |
| 8290 | { |
| 8291 | uiout->text (" received signal "); |
| 8292 | annotate_signal_name (); |
| 8293 | if (uiout->is_mi_like_p ()) |
| 8294 | uiout->field_string |
| 8295 | ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED)); |
| 8296 | uiout->field_string ("signal-name", gdb_signal_to_name (siggnal)); |
| 8297 | annotate_signal_name_end (); |
| 8298 | uiout->text (", "); |
| 8299 | annotate_signal_string (); |
| 8300 | uiout->field_string ("signal-meaning", gdb_signal_to_string (siggnal)); |
| 8301 | |
| 8302 | struct regcache *regcache = get_current_regcache (); |
| 8303 | struct gdbarch *gdbarch = regcache->arch (); |
| 8304 | if (gdbarch_report_signal_info_p (gdbarch)) |
| 8305 | gdbarch_report_signal_info (gdbarch, uiout, siggnal); |
| 8306 | |
| 8307 | annotate_signal_string_end (); |
| 8308 | } |
| 8309 | uiout->text (".\n"); |
| 8310 | } |
| 8311 | |
| 8312 | void |
| 8313 | print_no_history_reason (struct ui_out *uiout) |
| 8314 | { |
| 8315 | uiout->text ("\nNo more reverse-execution history.\n"); |
| 8316 | } |
| 8317 | |
| 8318 | /* Print current location without a level number, if we have changed |
| 8319 | functions or hit a breakpoint. Print source line if we have one. |
| 8320 | bpstat_print contains the logic deciding in detail what to print, |
| 8321 | based on the event(s) that just occurred. */ |
| 8322 | |
| 8323 | static void |
| 8324 | print_stop_location (struct target_waitstatus *ws) |
| 8325 | { |
| 8326 | int bpstat_ret; |
| 8327 | enum print_what source_flag; |
| 8328 | int do_frame_printing = 1; |
| 8329 | struct thread_info *tp = inferior_thread (); |
| 8330 | |
| 8331 | bpstat_ret = bpstat_print (tp->control.stop_bpstat, ws->kind); |
| 8332 | switch (bpstat_ret) |
| 8333 | { |
| 8334 | case PRINT_UNKNOWN: |
| 8335 | /* FIXME: cagney/2002-12-01: Given that a frame ID does (or |
| 8336 | should) carry around the function and does (or should) use |
| 8337 | that when doing a frame comparison. */ |
| 8338 | if (tp->control.stop_step |
| 8339 | && frame_id_eq (tp->control.step_frame_id, |
| 8340 | get_frame_id (get_current_frame ())) |
| 8341 | && (tp->control.step_start_function |
| 8342 | == find_pc_function (tp->suspend.stop_pc))) |
| 8343 | { |
| 8344 | /* Finished step, just print source line. */ |
| 8345 | source_flag = SRC_LINE; |
| 8346 | } |
| 8347 | else |
| 8348 | { |
| 8349 | /* Print location and source line. */ |
| 8350 | source_flag = SRC_AND_LOC; |
| 8351 | } |
| 8352 | break; |
| 8353 | case PRINT_SRC_AND_LOC: |
| 8354 | /* Print location and source line. */ |
| 8355 | source_flag = SRC_AND_LOC; |
| 8356 | break; |
| 8357 | case PRINT_SRC_ONLY: |
| 8358 | source_flag = SRC_LINE; |
| 8359 | break; |
| 8360 | case PRINT_NOTHING: |
| 8361 | /* Something bogus. */ |
| 8362 | source_flag = SRC_LINE; |
| 8363 | do_frame_printing = 0; |
| 8364 | break; |
| 8365 | default: |
| 8366 | internal_error (__FILE__, __LINE__, _("Unknown value.")); |
| 8367 | } |
| 8368 | |
| 8369 | /* The behavior of this routine with respect to the source |
| 8370 | flag is: |
| 8371 | SRC_LINE: Print only source line |
| 8372 | LOCATION: Print only location |
| 8373 | SRC_AND_LOC: Print location and source line. */ |
| 8374 | if (do_frame_printing) |
| 8375 | print_stack_frame (get_selected_frame (NULL), 0, source_flag, 1); |
| 8376 | } |
| 8377 | |
| 8378 | /* See infrun.h. */ |
| 8379 | |
| 8380 | void |
| 8381 | print_stop_event (struct ui_out *uiout, bool displays) |
| 8382 | { |
| 8383 | struct target_waitstatus last; |
| 8384 | struct thread_info *tp; |
| 8385 | |
| 8386 | get_last_target_status (nullptr, nullptr, &last); |
| 8387 | |
| 8388 | { |
| 8389 | scoped_restore save_uiout = make_scoped_restore (¤t_uiout, uiout); |
| 8390 | |
| 8391 | print_stop_location (&last); |
| 8392 | |
| 8393 | /* Display the auto-display expressions. */ |
| 8394 | if (displays) |
| 8395 | do_displays (); |
| 8396 | } |
| 8397 | |
| 8398 | tp = inferior_thread (); |
| 8399 | if (tp->thread_fsm != NULL |
| 8400 | && tp->thread_fsm->finished_p ()) |
| 8401 | { |
| 8402 | struct return_value_info *rv; |
| 8403 | |
| 8404 | rv = tp->thread_fsm->return_value (); |
| 8405 | if (rv != NULL) |
| 8406 | print_return_value (uiout, rv); |
| 8407 | } |
| 8408 | } |
| 8409 | |
| 8410 | /* See infrun.h. */ |
| 8411 | |
| 8412 | void |
| 8413 | maybe_remove_breakpoints (void) |
| 8414 | { |
| 8415 | if (!breakpoints_should_be_inserted_now () && target_has_execution ()) |
| 8416 | { |
| 8417 | if (remove_breakpoints ()) |
| 8418 | { |
| 8419 | target_terminal::ours_for_output (); |
| 8420 | printf_filtered (_("Cannot remove breakpoints because " |
| 8421 | "program is no longer writable.\nFurther " |
| 8422 | "execution is probably impossible.\n")); |
| 8423 | } |
| 8424 | } |
| 8425 | } |
| 8426 | |
| 8427 | /* The execution context that just caused a normal stop. */ |
| 8428 | |
| 8429 | struct stop_context |
| 8430 | { |
| 8431 | stop_context (); |
| 8432 | |
| 8433 | DISABLE_COPY_AND_ASSIGN (stop_context); |
| 8434 | |
| 8435 | bool changed () const; |
| 8436 | |
| 8437 | /* The stop ID. */ |
| 8438 | ULONGEST stop_id; |
| 8439 | |
| 8440 | /* The event PTID. */ |
| 8441 | |
| 8442 | ptid_t ptid; |
| 8443 | |
| 8444 | /* If stopp for a thread event, this is the thread that caused the |
| 8445 | stop. */ |
| 8446 | thread_info_ref thread; |
| 8447 | |
| 8448 | /* The inferior that caused the stop. */ |
| 8449 | int inf_num; |
| 8450 | }; |
| 8451 | |
| 8452 | /* Initializes a new stop context. If stopped for a thread event, this |
| 8453 | takes a strong reference to the thread. */ |
| 8454 | |
| 8455 | stop_context::stop_context () |
| 8456 | { |
| 8457 | stop_id = get_stop_id (); |
| 8458 | ptid = inferior_ptid; |
| 8459 | inf_num = current_inferior ()->num; |
| 8460 | |
| 8461 | if (inferior_ptid != null_ptid) |
| 8462 | { |
| 8463 | /* Take a strong reference so that the thread can't be deleted |
| 8464 | yet. */ |
| 8465 | thread = thread_info_ref::new_reference (inferior_thread ()); |
| 8466 | } |
| 8467 | } |
| 8468 | |
| 8469 | /* Return true if the current context no longer matches the saved stop |
| 8470 | context. */ |
| 8471 | |
| 8472 | bool |
| 8473 | stop_context::changed () const |
| 8474 | { |
| 8475 | if (ptid != inferior_ptid) |
| 8476 | return true; |
| 8477 | if (inf_num != current_inferior ()->num) |
| 8478 | return true; |
| 8479 | if (thread != NULL && thread->state != THREAD_STOPPED) |
| 8480 | return true; |
| 8481 | if (get_stop_id () != stop_id) |
| 8482 | return true; |
| 8483 | return false; |
| 8484 | } |
| 8485 | |
| 8486 | /* See infrun.h. */ |
| 8487 | |
| 8488 | int |
| 8489 | normal_stop (void) |
| 8490 | { |
| 8491 | struct target_waitstatus last; |
| 8492 | |
| 8493 | get_last_target_status (nullptr, nullptr, &last); |
| 8494 | |
| 8495 | new_stop_id (); |
| 8496 | |
| 8497 | /* If an exception is thrown from this point on, make sure to |
| 8498 | propagate GDB's knowledge of the executing state to the |
| 8499 | frontend/user running state. A QUIT is an easy exception to see |
| 8500 | here, so do this before any filtered output. */ |
| 8501 | |
| 8502 | ptid_t finish_ptid = null_ptid; |
| 8503 | |
| 8504 | if (!non_stop) |
| 8505 | finish_ptid = minus_one_ptid; |
| 8506 | else if (last.kind == TARGET_WAITKIND_SIGNALLED |
| 8507 | || last.kind == TARGET_WAITKIND_EXITED) |
| 8508 | { |
| 8509 | /* On some targets, we may still have live threads in the |
| 8510 | inferior when we get a process exit event. E.g., for |
| 8511 | "checkpoint", when the current checkpoint/fork exits, |
| 8512 | linux-fork.c automatically switches to another fork from |
| 8513 | within target_mourn_inferior. */ |
| 8514 | if (inferior_ptid != null_ptid) |
| 8515 | finish_ptid = ptid_t (inferior_ptid.pid ()); |
| 8516 | } |
| 8517 | else if (last.kind != TARGET_WAITKIND_NO_RESUMED) |
| 8518 | finish_ptid = inferior_ptid; |
| 8519 | |
| 8520 | gdb::optional<scoped_finish_thread_state> maybe_finish_thread_state; |
| 8521 | if (finish_ptid != null_ptid) |
| 8522 | { |
| 8523 | maybe_finish_thread_state.emplace |
| 8524 | (user_visible_resume_target (finish_ptid), finish_ptid); |
| 8525 | } |
| 8526 | |
| 8527 | /* As we're presenting a stop, and potentially removing breakpoints, |
| 8528 | update the thread list so we can tell whether there are threads |
| 8529 | running on the target. With target remote, for example, we can |
| 8530 | only learn about new threads when we explicitly update the thread |
| 8531 | list. Do this before notifying the interpreters about signal |
| 8532 | stops, end of stepping ranges, etc., so that the "new thread" |
| 8533 | output is emitted before e.g., "Program received signal FOO", |
| 8534 | instead of after. */ |
| 8535 | update_thread_list (); |
| 8536 | |
| 8537 | if (last.kind == TARGET_WAITKIND_STOPPED && stopped_by_random_signal) |
| 8538 | gdb::observers::signal_received.notify (inferior_thread ()->suspend.stop_signal); |
| 8539 | |
| 8540 | /* As with the notification of thread events, we want to delay |
| 8541 | notifying the user that we've switched thread context until |
| 8542 | the inferior actually stops. |
| 8543 | |
| 8544 | There's no point in saying anything if the inferior has exited. |
| 8545 | Note that SIGNALLED here means "exited with a signal", not |
| 8546 | "received a signal". |
| 8547 | |
| 8548 | Also skip saying anything in non-stop mode. In that mode, as we |
| 8549 | don't want GDB to switch threads behind the user's back, to avoid |
| 8550 | races where the user is typing a command to apply to thread x, |
| 8551 | but GDB switches to thread y before the user finishes entering |
| 8552 | the command, fetch_inferior_event installs a cleanup to restore |
| 8553 | the current thread back to the thread the user had selected right |
| 8554 | after this event is handled, so we're not really switching, only |
| 8555 | informing of a stop. */ |
| 8556 | if (!non_stop |
| 8557 | && previous_inferior_ptid != inferior_ptid |
| 8558 | && target_has_execution () |
| 8559 | && last.kind != TARGET_WAITKIND_SIGNALLED |
| 8560 | && last.kind != TARGET_WAITKIND_EXITED |
| 8561 | && last.kind != TARGET_WAITKIND_NO_RESUMED) |
| 8562 | { |
| 8563 | SWITCH_THRU_ALL_UIS () |
| 8564 | { |
| 8565 | target_terminal::ours_for_output (); |
| 8566 | printf_filtered (_("[Switching to %s]\n"), |
| 8567 | target_pid_to_str (inferior_ptid).c_str ()); |
| 8568 | annotate_thread_changed (); |
| 8569 | } |
| 8570 | previous_inferior_ptid = inferior_ptid; |
| 8571 | } |
| 8572 | |
| 8573 | if (last.kind == TARGET_WAITKIND_NO_RESUMED) |
| 8574 | { |
| 8575 | SWITCH_THRU_ALL_UIS () |
| 8576 | if (current_ui->prompt_state == PROMPT_BLOCKED) |
| 8577 | { |
| 8578 | target_terminal::ours_for_output (); |
| 8579 | printf_filtered (_("No unwaited-for children left.\n")); |
| 8580 | } |
| 8581 | } |
| 8582 | |
| 8583 | /* Note: this depends on the update_thread_list call above. */ |
| 8584 | maybe_remove_breakpoints (); |
| 8585 | |
| 8586 | /* If an auto-display called a function and that got a signal, |
| 8587 | delete that auto-display to avoid an infinite recursion. */ |
| 8588 | |
| 8589 | if (stopped_by_random_signal) |
| 8590 | disable_current_display (); |
| 8591 | |
| 8592 | SWITCH_THRU_ALL_UIS () |
| 8593 | { |
| 8594 | async_enable_stdin (); |
| 8595 | } |
| 8596 | |
| 8597 | /* Let the user/frontend see the threads as stopped. */ |
| 8598 | maybe_finish_thread_state.reset (); |
| 8599 | |
| 8600 | /* Select innermost stack frame - i.e., current frame is frame 0, |
| 8601 | and current location is based on that. Handle the case where the |
| 8602 | dummy call is returning after being stopped. E.g. the dummy call |
| 8603 | previously hit a breakpoint. (If the dummy call returns |
| 8604 | normally, we won't reach here.) Do this before the stop hook is |
| 8605 | run, so that it doesn't get to see the temporary dummy frame, |
| 8606 | which is not where we'll present the stop. */ |
| 8607 | if (has_stack_frames ()) |
| 8608 | { |
| 8609 | if (stop_stack_dummy == STOP_STACK_DUMMY) |
| 8610 | { |
| 8611 | /* Pop the empty frame that contains the stack dummy. This |
| 8612 | also restores inferior state prior to the call (struct |
| 8613 | infcall_suspend_state). */ |
| 8614 | struct frame_info *frame = get_current_frame (); |
| 8615 | |
| 8616 | gdb_assert (get_frame_type (frame) == DUMMY_FRAME); |
| 8617 | frame_pop (frame); |
| 8618 | /* frame_pop calls reinit_frame_cache as the last thing it |
| 8619 | does which means there's now no selected frame. */ |
| 8620 | } |
| 8621 | |
| 8622 | select_frame (get_current_frame ()); |
| 8623 | |
| 8624 | /* Set the current source location. */ |
| 8625 | set_current_sal_from_frame (get_current_frame ()); |
| 8626 | } |
| 8627 | |
| 8628 | /* Look up the hook_stop and run it (CLI internally handles problem |
| 8629 | of stop_command's pre-hook not existing). */ |
| 8630 | if (stop_command != NULL) |
| 8631 | { |
| 8632 | stop_context saved_context; |
| 8633 | |
| 8634 | try |
| 8635 | { |
| 8636 | execute_cmd_pre_hook (stop_command); |
| 8637 | } |
| 8638 | catch (const gdb_exception &ex) |
| 8639 | { |
| 8640 | exception_fprintf (gdb_stderr, ex, |
| 8641 | "Error while running hook_stop:\n"); |
| 8642 | } |
| 8643 | |
| 8644 | /* If the stop hook resumes the target, then there's no point in |
| 8645 | trying to notify about the previous stop; its context is |
| 8646 | gone. Likewise if the command switches thread or inferior -- |
| 8647 | the observers would print a stop for the wrong |
| 8648 | thread/inferior. */ |
| 8649 | if (saved_context.changed ()) |
| 8650 | return 1; |
| 8651 | } |
| 8652 | |
| 8653 | /* Notify observers about the stop. This is where the interpreters |
| 8654 | print the stop event. */ |
| 8655 | if (inferior_ptid != null_ptid) |
| 8656 | gdb::observers::normal_stop.notify (inferior_thread ()->control.stop_bpstat, |
| 8657 | stop_print_frame); |
| 8658 | else |
| 8659 | gdb::observers::normal_stop.notify (NULL, stop_print_frame); |
| 8660 | |
| 8661 | annotate_stopped (); |
| 8662 | |
| 8663 | if (target_has_execution ()) |
| 8664 | { |
| 8665 | if (last.kind != TARGET_WAITKIND_SIGNALLED |
| 8666 | && last.kind != TARGET_WAITKIND_EXITED |
| 8667 | && last.kind != TARGET_WAITKIND_NO_RESUMED) |
| 8668 | /* Delete the breakpoint we stopped at, if it wants to be deleted. |
| 8669 | Delete any breakpoint that is to be deleted at the next stop. */ |
| 8670 | breakpoint_auto_delete (inferior_thread ()->control.stop_bpstat); |
| 8671 | } |
| 8672 | |
| 8673 | /* Try to get rid of automatically added inferiors that are no |
| 8674 | longer needed. Keeping those around slows down things linearly. |
| 8675 | Note that this never removes the current inferior. */ |
| 8676 | prune_inferiors (); |
| 8677 | |
| 8678 | return 0; |
| 8679 | } |
| 8680 | \f |
| 8681 | int |
| 8682 | signal_stop_state (int signo) |
| 8683 | { |
| 8684 | return signal_stop[signo]; |
| 8685 | } |
| 8686 | |
| 8687 | int |
| 8688 | signal_print_state (int signo) |
| 8689 | { |
| 8690 | return signal_print[signo]; |
| 8691 | } |
| 8692 | |
| 8693 | int |
| 8694 | signal_pass_state (int signo) |
| 8695 | { |
| 8696 | return signal_program[signo]; |
| 8697 | } |
| 8698 | |
| 8699 | static void |
| 8700 | signal_cache_update (int signo) |
| 8701 | { |
| 8702 | if (signo == -1) |
| 8703 | { |
| 8704 | for (signo = 0; signo < (int) GDB_SIGNAL_LAST; signo++) |
| 8705 | signal_cache_update (signo); |
| 8706 | |
| 8707 | return; |
| 8708 | } |
| 8709 | |
| 8710 | signal_pass[signo] = (signal_stop[signo] == 0 |
| 8711 | && signal_print[signo] == 0 |
| 8712 | && signal_program[signo] == 1 |
| 8713 | && signal_catch[signo] == 0); |
| 8714 | } |
| 8715 | |
| 8716 | int |
| 8717 | signal_stop_update (int signo, int state) |
| 8718 | { |
| 8719 | int ret = signal_stop[signo]; |
| 8720 | |
| 8721 | signal_stop[signo] = state; |
| 8722 | signal_cache_update (signo); |
| 8723 | return ret; |
| 8724 | } |
| 8725 | |
| 8726 | int |
| 8727 | signal_print_update (int signo, int state) |
| 8728 | { |
| 8729 | int ret = signal_print[signo]; |
| 8730 | |
| 8731 | signal_print[signo] = state; |
| 8732 | signal_cache_update (signo); |
| 8733 | return ret; |
| 8734 | } |
| 8735 | |
| 8736 | int |
| 8737 | signal_pass_update (int signo, int state) |
| 8738 | { |
| 8739 | int ret = signal_program[signo]; |
| 8740 | |
| 8741 | signal_program[signo] = state; |
| 8742 | signal_cache_update (signo); |
| 8743 | return ret; |
| 8744 | } |
| 8745 | |
| 8746 | /* Update the global 'signal_catch' from INFO and notify the |
| 8747 | target. */ |
| 8748 | |
| 8749 | void |
| 8750 | signal_catch_update (const unsigned int *info) |
| 8751 | { |
| 8752 | int i; |
| 8753 | |
| 8754 | for (i = 0; i < GDB_SIGNAL_LAST; ++i) |
| 8755 | signal_catch[i] = info[i] > 0; |
| 8756 | signal_cache_update (-1); |
| 8757 | target_pass_signals (signal_pass); |
| 8758 | } |
| 8759 | |
| 8760 | static void |
| 8761 | sig_print_header (void) |
| 8762 | { |
| 8763 | printf_filtered (_("Signal Stop\tPrint\tPass " |
| 8764 | "to program\tDescription\n")); |
| 8765 | } |
| 8766 | |
| 8767 | static void |
| 8768 | sig_print_info (enum gdb_signal oursig) |
| 8769 | { |
| 8770 | const char *name = gdb_signal_to_name (oursig); |
| 8771 | int name_padding = 13 - strlen (name); |
| 8772 | |
| 8773 | if (name_padding <= 0) |
| 8774 | name_padding = 0; |
| 8775 | |
| 8776 | printf_filtered ("%s", name); |
| 8777 | printf_filtered ("%*.*s ", name_padding, name_padding, " "); |
| 8778 | printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No"); |
| 8779 | printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No"); |
| 8780 | printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No"); |
| 8781 | printf_filtered ("%s\n", gdb_signal_to_string (oursig)); |
| 8782 | } |
| 8783 | |
| 8784 | /* Specify how various signals in the inferior should be handled. */ |
| 8785 | |
| 8786 | static void |
| 8787 | handle_command (const char *args, int from_tty) |
| 8788 | { |
| 8789 | int digits, wordlen; |
| 8790 | int sigfirst, siglast; |
| 8791 | enum gdb_signal oursig; |
| 8792 | int allsigs; |
| 8793 | |
| 8794 | if (args == NULL) |
| 8795 | { |
| 8796 | error_no_arg (_("signal to handle")); |
| 8797 | } |
| 8798 | |
| 8799 | /* Allocate and zero an array of flags for which signals to handle. */ |
| 8800 | |
| 8801 | const size_t nsigs = GDB_SIGNAL_LAST; |
| 8802 | unsigned char sigs[nsigs] {}; |
| 8803 | |
| 8804 | /* Break the command line up into args. */ |
| 8805 | |
| 8806 | gdb_argv built_argv (args); |
| 8807 | |
| 8808 | /* Walk through the args, looking for signal oursigs, signal names, and |
| 8809 | actions. Signal numbers and signal names may be interspersed with |
| 8810 | actions, with the actions being performed for all signals cumulatively |
| 8811 | specified. Signal ranges can be specified as <LOW>-<HIGH>. */ |
| 8812 | |
| 8813 | for (char *arg : built_argv) |
| 8814 | { |
| 8815 | wordlen = strlen (arg); |
| 8816 | for (digits = 0; isdigit (arg[digits]); digits++) |
| 8817 | {; |
| 8818 | } |
| 8819 | allsigs = 0; |
| 8820 | sigfirst = siglast = -1; |
| 8821 | |
| 8822 | if (wordlen >= 1 && !strncmp (arg, "all", wordlen)) |
| 8823 | { |
| 8824 | /* Apply action to all signals except those used by the |
| 8825 | debugger. Silently skip those. */ |
| 8826 | allsigs = 1; |
| 8827 | sigfirst = 0; |
| 8828 | siglast = nsigs - 1; |
| 8829 | } |
| 8830 | else if (wordlen >= 1 && !strncmp (arg, "stop", wordlen)) |
| 8831 | { |
| 8832 | SET_SIGS (nsigs, sigs, signal_stop); |
| 8833 | SET_SIGS (nsigs, sigs, signal_print); |
| 8834 | } |
| 8835 | else if (wordlen >= 1 && !strncmp (arg, "ignore", wordlen)) |
| 8836 | { |
| 8837 | UNSET_SIGS (nsigs, sigs, signal_program); |
| 8838 | } |
| 8839 | else if (wordlen >= 2 && !strncmp (arg, "print", wordlen)) |
| 8840 | { |
| 8841 | SET_SIGS (nsigs, sigs, signal_print); |
| 8842 | } |
| 8843 | else if (wordlen >= 2 && !strncmp (arg, "pass", wordlen)) |
| 8844 | { |
| 8845 | SET_SIGS (nsigs, sigs, signal_program); |
| 8846 | } |
| 8847 | else if (wordlen >= 3 && !strncmp (arg, "nostop", wordlen)) |
| 8848 | { |
| 8849 | UNSET_SIGS (nsigs, sigs, signal_stop); |
| 8850 | } |
| 8851 | else if (wordlen >= 3 && !strncmp (arg, "noignore", wordlen)) |
| 8852 | { |
| 8853 | SET_SIGS (nsigs, sigs, signal_program); |
| 8854 | } |
| 8855 | else if (wordlen >= 4 && !strncmp (arg, "noprint", wordlen)) |
| 8856 | { |
| 8857 | UNSET_SIGS (nsigs, sigs, signal_print); |
| 8858 | UNSET_SIGS (nsigs, sigs, signal_stop); |
| 8859 | } |
| 8860 | else if (wordlen >= 4 && !strncmp (arg, "nopass", wordlen)) |
| 8861 | { |
| 8862 | UNSET_SIGS (nsigs, sigs, signal_program); |
| 8863 | } |
| 8864 | else if (digits > 0) |
| 8865 | { |
| 8866 | /* It is numeric. The numeric signal refers to our own |
| 8867 | internal signal numbering from target.h, not to host/target |
| 8868 | signal number. This is a feature; users really should be |
| 8869 | using symbolic names anyway, and the common ones like |
| 8870 | SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */ |
| 8871 | |
| 8872 | sigfirst = siglast = (int) |
| 8873 | gdb_signal_from_command (atoi (arg)); |
| 8874 | if (arg[digits] == '-') |
| 8875 | { |
| 8876 | siglast = (int) |
| 8877 | gdb_signal_from_command (atoi (arg + digits + 1)); |
| 8878 | } |
| 8879 | if (sigfirst > siglast) |
| 8880 | { |
| 8881 | /* Bet he didn't figure we'd think of this case... */ |
| 8882 | std::swap (sigfirst, siglast); |
| 8883 | } |
| 8884 | } |
| 8885 | else |
| 8886 | { |
| 8887 | oursig = gdb_signal_from_name (arg); |
| 8888 | if (oursig != GDB_SIGNAL_UNKNOWN) |
| 8889 | { |
| 8890 | sigfirst = siglast = (int) oursig; |
| 8891 | } |
| 8892 | else |
| 8893 | { |
| 8894 | /* Not a number and not a recognized flag word => complain. */ |
| 8895 | error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg); |
| 8896 | } |
| 8897 | } |
| 8898 | |
| 8899 | /* If any signal numbers or symbol names were found, set flags for |
| 8900 | which signals to apply actions to. */ |
| 8901 | |
| 8902 | for (int signum = sigfirst; signum >= 0 && signum <= siglast; signum++) |
| 8903 | { |
| 8904 | switch ((enum gdb_signal) signum) |
| 8905 | { |
| 8906 | case GDB_SIGNAL_TRAP: |
| 8907 | case GDB_SIGNAL_INT: |
| 8908 | if (!allsigs && !sigs[signum]) |
| 8909 | { |
| 8910 | if (query (_("%s is used by the debugger.\n\ |
| 8911 | Are you sure you want to change it? "), |
| 8912 | gdb_signal_to_name ((enum gdb_signal) signum))) |
| 8913 | { |
| 8914 | sigs[signum] = 1; |
| 8915 | } |
| 8916 | else |
| 8917 | printf_unfiltered (_("Not confirmed, unchanged.\n")); |
| 8918 | } |
| 8919 | break; |
| 8920 | case GDB_SIGNAL_0: |
| 8921 | case GDB_SIGNAL_DEFAULT: |
| 8922 | case GDB_SIGNAL_UNKNOWN: |
| 8923 | /* Make sure that "all" doesn't print these. */ |
| 8924 | break; |
| 8925 | default: |
| 8926 | sigs[signum] = 1; |
| 8927 | break; |
| 8928 | } |
| 8929 | } |
| 8930 | } |
| 8931 | |
| 8932 | for (int signum = 0; signum < nsigs; signum++) |
| 8933 | if (sigs[signum]) |
| 8934 | { |
| 8935 | signal_cache_update (-1); |
| 8936 | target_pass_signals (signal_pass); |
| 8937 | target_program_signals (signal_program); |
| 8938 | |
| 8939 | if (from_tty) |
| 8940 | { |
| 8941 | /* Show the results. */ |
| 8942 | sig_print_header (); |
| 8943 | for (; signum < nsigs; signum++) |
| 8944 | if (sigs[signum]) |
| 8945 | sig_print_info ((enum gdb_signal) signum); |
| 8946 | } |
| 8947 | |
| 8948 | break; |
| 8949 | } |
| 8950 | } |
| 8951 | |
| 8952 | /* Complete the "handle" command. */ |
| 8953 | |
| 8954 | static void |
| 8955 | handle_completer (struct cmd_list_element *ignore, |
| 8956 | completion_tracker &tracker, |
| 8957 | const char *text, const char *word) |
| 8958 | { |
| 8959 | static const char * const keywords[] = |
| 8960 | { |
| 8961 | "all", |
| 8962 | "stop", |
| 8963 | "ignore", |
| 8964 | "print", |
| 8965 | "pass", |
| 8966 | "nostop", |
| 8967 | "noignore", |
| 8968 | "noprint", |
| 8969 | "nopass", |
| 8970 | NULL, |
| 8971 | }; |
| 8972 | |
| 8973 | signal_completer (ignore, tracker, text, word); |
| 8974 | complete_on_enum (tracker, keywords, word, word); |
| 8975 | } |
| 8976 | |
| 8977 | enum gdb_signal |
| 8978 | gdb_signal_from_command (int num) |
| 8979 | { |
| 8980 | if (num >= 1 && num <= 15) |
| 8981 | return (enum gdb_signal) num; |
| 8982 | error (_("Only signals 1-15 are valid as numeric signals.\n\ |
| 8983 | Use \"info signals\" for a list of symbolic signals.")); |
| 8984 | } |
| 8985 | |
| 8986 | /* Print current contents of the tables set by the handle command. |
| 8987 | It is possible we should just be printing signals actually used |
| 8988 | by the current target (but for things to work right when switching |
| 8989 | targets, all signals should be in the signal tables). */ |
| 8990 | |
| 8991 | static void |
| 8992 | info_signals_command (const char *signum_exp, int from_tty) |
| 8993 | { |
| 8994 | enum gdb_signal oursig; |
| 8995 | |
| 8996 | sig_print_header (); |
| 8997 | |
| 8998 | if (signum_exp) |
| 8999 | { |
| 9000 | /* First see if this is a symbol name. */ |
| 9001 | oursig = gdb_signal_from_name (signum_exp); |
| 9002 | if (oursig == GDB_SIGNAL_UNKNOWN) |
| 9003 | { |
| 9004 | /* No, try numeric. */ |
| 9005 | oursig = |
| 9006 | gdb_signal_from_command (parse_and_eval_long (signum_exp)); |
| 9007 | } |
| 9008 | sig_print_info (oursig); |
| 9009 | return; |
| 9010 | } |
| 9011 | |
| 9012 | printf_filtered ("\n"); |
| 9013 | /* These ugly casts brought to you by the native VAX compiler. */ |
| 9014 | for (oursig = GDB_SIGNAL_FIRST; |
| 9015 | (int) oursig < (int) GDB_SIGNAL_LAST; |
| 9016 | oursig = (enum gdb_signal) ((int) oursig + 1)) |
| 9017 | { |
| 9018 | QUIT; |
| 9019 | |
| 9020 | if (oursig != GDB_SIGNAL_UNKNOWN |
| 9021 | && oursig != GDB_SIGNAL_DEFAULT && oursig != GDB_SIGNAL_0) |
| 9022 | sig_print_info (oursig); |
| 9023 | } |
| 9024 | |
| 9025 | printf_filtered (_("\nUse the \"handle\" command " |
| 9026 | "to change these tables.\n")); |
| 9027 | } |
| 9028 | |
| 9029 | /* The $_siginfo convenience variable is a bit special. We don't know |
| 9030 | for sure the type of the value until we actually have a chance to |
| 9031 | fetch the data. The type can change depending on gdbarch, so it is |
| 9032 | also dependent on which thread you have selected. |
| 9033 | |
| 9034 | 1. making $_siginfo be an internalvar that creates a new value on |
| 9035 | access. |
| 9036 | |
| 9037 | 2. making the value of $_siginfo be an lval_computed value. */ |
| 9038 | |
| 9039 | /* This function implements the lval_computed support for reading a |
| 9040 | $_siginfo value. */ |
| 9041 | |
| 9042 | static void |
| 9043 | siginfo_value_read (struct value *v) |
| 9044 | { |
| 9045 | LONGEST transferred; |
| 9046 | |
| 9047 | /* If we can access registers, so can we access $_siginfo. Likewise |
| 9048 | vice versa. */ |
| 9049 | validate_registers_access (); |
| 9050 | |
| 9051 | transferred = |
| 9052 | target_read (current_inferior ()->top_target (), |
| 9053 | TARGET_OBJECT_SIGNAL_INFO, |
| 9054 | NULL, |
| 9055 | value_contents_all_raw (v), |
| 9056 | value_offset (v), |
| 9057 | TYPE_LENGTH (value_type (v))); |
| 9058 | |
| 9059 | if (transferred != TYPE_LENGTH (value_type (v))) |
| 9060 | error (_("Unable to read siginfo")); |
| 9061 | } |
| 9062 | |
| 9063 | /* This function implements the lval_computed support for writing a |
| 9064 | $_siginfo value. */ |
| 9065 | |
| 9066 | static void |
| 9067 | siginfo_value_write (struct value *v, struct value *fromval) |
| 9068 | { |
| 9069 | LONGEST transferred; |
| 9070 | |
| 9071 | /* If we can access registers, so can we access $_siginfo. Likewise |
| 9072 | vice versa. */ |
| 9073 | validate_registers_access (); |
| 9074 | |
| 9075 | transferred = target_write (current_inferior ()->top_target (), |
| 9076 | TARGET_OBJECT_SIGNAL_INFO, |
| 9077 | NULL, |
| 9078 | value_contents_all_raw (fromval), |
| 9079 | value_offset (v), |
| 9080 | TYPE_LENGTH (value_type (fromval))); |
| 9081 | |
| 9082 | if (transferred != TYPE_LENGTH (value_type (fromval))) |
| 9083 | error (_("Unable to write siginfo")); |
| 9084 | } |
| 9085 | |
| 9086 | static const struct lval_funcs siginfo_value_funcs = |
| 9087 | { |
| 9088 | siginfo_value_read, |
| 9089 | siginfo_value_write |
| 9090 | }; |
| 9091 | |
| 9092 | /* Return a new value with the correct type for the siginfo object of |
| 9093 | the current thread using architecture GDBARCH. Return a void value |
| 9094 | if there's no object available. */ |
| 9095 | |
| 9096 | static struct value * |
| 9097 | siginfo_make_value (struct gdbarch *gdbarch, struct internalvar *var, |
| 9098 | void *ignore) |
| 9099 | { |
| 9100 | if (target_has_stack () |
| 9101 | && inferior_ptid != null_ptid |
| 9102 | && gdbarch_get_siginfo_type_p (gdbarch)) |
| 9103 | { |
| 9104 | struct type *type = gdbarch_get_siginfo_type (gdbarch); |
| 9105 | |
| 9106 | return allocate_computed_value (type, &siginfo_value_funcs, NULL); |
| 9107 | } |
| 9108 | |
| 9109 | return allocate_value (builtin_type (gdbarch)->builtin_void); |
| 9110 | } |
| 9111 | |
| 9112 | \f |
| 9113 | /* infcall_suspend_state contains state about the program itself like its |
| 9114 | registers and any signal it received when it last stopped. |
| 9115 | This state must be restored regardless of how the inferior function call |
| 9116 | ends (either successfully, or after it hits a breakpoint or signal) |
| 9117 | if the program is to properly continue where it left off. */ |
| 9118 | |
| 9119 | class infcall_suspend_state |
| 9120 | { |
| 9121 | public: |
| 9122 | /* Capture state from GDBARCH, TP, and REGCACHE that must be restored |
| 9123 | once the inferior function call has finished. */ |
| 9124 | infcall_suspend_state (struct gdbarch *gdbarch, |
| 9125 | const struct thread_info *tp, |
| 9126 | struct regcache *regcache) |
| 9127 | : m_thread_suspend (tp->suspend), |
| 9128 | m_registers (new readonly_detached_regcache (*regcache)) |
| 9129 | { |
| 9130 | gdb::unique_xmalloc_ptr<gdb_byte> siginfo_data; |
| 9131 | |
| 9132 | if (gdbarch_get_siginfo_type_p (gdbarch)) |
| 9133 | { |
| 9134 | struct type *type = gdbarch_get_siginfo_type (gdbarch); |
| 9135 | size_t len = TYPE_LENGTH (type); |
| 9136 | |
| 9137 | siginfo_data.reset ((gdb_byte *) xmalloc (len)); |
| 9138 | |
| 9139 | if (target_read (current_inferior ()->top_target (), |
| 9140 | TARGET_OBJECT_SIGNAL_INFO, NULL, |
| 9141 | siginfo_data.get (), 0, len) != len) |
| 9142 | { |
| 9143 | /* Errors ignored. */ |
| 9144 | siginfo_data.reset (nullptr); |
| 9145 | } |
| 9146 | } |
| 9147 | |
| 9148 | if (siginfo_data) |
| 9149 | { |
| 9150 | m_siginfo_gdbarch = gdbarch; |
| 9151 | m_siginfo_data = std::move (siginfo_data); |
| 9152 | } |
| 9153 | } |
| 9154 | |
| 9155 | /* Return a pointer to the stored register state. */ |
| 9156 | |
| 9157 | readonly_detached_regcache *registers () const |
| 9158 | { |
| 9159 | return m_registers.get (); |
| 9160 | } |
| 9161 | |
| 9162 | /* Restores the stored state into GDBARCH, TP, and REGCACHE. */ |
| 9163 | |
| 9164 | void restore (struct gdbarch *gdbarch, |
| 9165 | struct thread_info *tp, |
| 9166 | struct regcache *regcache) const |
| 9167 | { |
| 9168 | tp->suspend = m_thread_suspend; |
| 9169 | |
| 9170 | if (m_siginfo_gdbarch == gdbarch) |
| 9171 | { |
| 9172 | struct type *type = gdbarch_get_siginfo_type (gdbarch); |
| 9173 | |
| 9174 | /* Errors ignored. */ |
| 9175 | target_write (current_inferior ()->top_target (), |
| 9176 | TARGET_OBJECT_SIGNAL_INFO, NULL, |
| 9177 | m_siginfo_data.get (), 0, TYPE_LENGTH (type)); |
| 9178 | } |
| 9179 | |
| 9180 | /* The inferior can be gone if the user types "print exit(0)" |
| 9181 | (and perhaps other times). */ |
| 9182 | if (target_has_execution ()) |
| 9183 | /* NB: The register write goes through to the target. */ |
| 9184 | regcache->restore (registers ()); |
| 9185 | } |
| 9186 | |
| 9187 | private: |
| 9188 | /* How the current thread stopped before the inferior function call was |
| 9189 | executed. */ |
| 9190 | struct thread_suspend_state m_thread_suspend; |
| 9191 | |
| 9192 | /* The registers before the inferior function call was executed. */ |
| 9193 | std::unique_ptr<readonly_detached_regcache> m_registers; |
| 9194 | |
| 9195 | /* Format of SIGINFO_DATA or NULL if it is not present. */ |
| 9196 | struct gdbarch *m_siginfo_gdbarch = nullptr; |
| 9197 | |
| 9198 | /* The inferior format depends on SIGINFO_GDBARCH and it has a length of |
| 9199 | TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the |
| 9200 | content would be invalid. */ |
| 9201 | gdb::unique_xmalloc_ptr<gdb_byte> m_siginfo_data; |
| 9202 | }; |
| 9203 | |
| 9204 | infcall_suspend_state_up |
| 9205 | save_infcall_suspend_state () |
| 9206 | { |
| 9207 | struct thread_info *tp = inferior_thread (); |
| 9208 | struct regcache *regcache = get_current_regcache (); |
| 9209 | struct gdbarch *gdbarch = regcache->arch (); |
| 9210 | |
| 9211 | infcall_suspend_state_up inf_state |
| 9212 | (new struct infcall_suspend_state (gdbarch, tp, regcache)); |
| 9213 | |
| 9214 | /* Having saved the current state, adjust the thread state, discarding |
| 9215 | any stop signal information. The stop signal is not useful when |
| 9216 | starting an inferior function call, and run_inferior_call will not use |
| 9217 | the signal due to its `proceed' call with GDB_SIGNAL_0. */ |
| 9218 | tp->suspend.stop_signal = GDB_SIGNAL_0; |
| 9219 | |
| 9220 | return inf_state; |
| 9221 | } |
| 9222 | |
| 9223 | /* Restore inferior session state to INF_STATE. */ |
| 9224 | |
| 9225 | void |
| 9226 | restore_infcall_suspend_state (struct infcall_suspend_state *inf_state) |
| 9227 | { |
| 9228 | struct thread_info *tp = inferior_thread (); |
| 9229 | struct regcache *regcache = get_current_regcache (); |
| 9230 | struct gdbarch *gdbarch = regcache->arch (); |
| 9231 | |
| 9232 | inf_state->restore (gdbarch, tp, regcache); |
| 9233 | discard_infcall_suspend_state (inf_state); |
| 9234 | } |
| 9235 | |
| 9236 | void |
| 9237 | discard_infcall_suspend_state (struct infcall_suspend_state *inf_state) |
| 9238 | { |
| 9239 | delete inf_state; |
| 9240 | } |
| 9241 | |
| 9242 | readonly_detached_regcache * |
| 9243 | get_infcall_suspend_state_regcache (struct infcall_suspend_state *inf_state) |
| 9244 | { |
| 9245 | return inf_state->registers (); |
| 9246 | } |
| 9247 | |
| 9248 | /* infcall_control_state contains state regarding gdb's control of the |
| 9249 | inferior itself like stepping control. It also contains session state like |
| 9250 | the user's currently selected frame. */ |
| 9251 | |
| 9252 | struct infcall_control_state |
| 9253 | { |
| 9254 | struct thread_control_state thread_control; |
| 9255 | struct inferior_control_state inferior_control; |
| 9256 | |
| 9257 | /* Other fields: */ |
| 9258 | enum stop_stack_kind stop_stack_dummy = STOP_NONE; |
| 9259 | int stopped_by_random_signal = 0; |
| 9260 | |
| 9261 | /* ID and level of the selected frame when the inferior function |
| 9262 | call was made. */ |
| 9263 | struct frame_id selected_frame_id {}; |
| 9264 | int selected_frame_level = -1; |
| 9265 | }; |
| 9266 | |
| 9267 | /* Save all of the information associated with the inferior<==>gdb |
| 9268 | connection. */ |
| 9269 | |
| 9270 | infcall_control_state_up |
| 9271 | save_infcall_control_state () |
| 9272 | { |
| 9273 | infcall_control_state_up inf_status (new struct infcall_control_state); |
| 9274 | struct thread_info *tp = inferior_thread (); |
| 9275 | struct inferior *inf = current_inferior (); |
| 9276 | |
| 9277 | inf_status->thread_control = tp->control; |
| 9278 | inf_status->inferior_control = inf->control; |
| 9279 | |
| 9280 | tp->control.step_resume_breakpoint = NULL; |
| 9281 | tp->control.exception_resume_breakpoint = NULL; |
| 9282 | |
| 9283 | /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of |
| 9284 | chain. If caller's caller is walking the chain, they'll be happier if we |
| 9285 | hand them back the original chain when restore_infcall_control_state is |
| 9286 | called. */ |
| 9287 | tp->control.stop_bpstat = bpstat_copy (tp->control.stop_bpstat); |
| 9288 | |
| 9289 | /* Other fields: */ |
| 9290 | inf_status->stop_stack_dummy = stop_stack_dummy; |
| 9291 | inf_status->stopped_by_random_signal = stopped_by_random_signal; |
| 9292 | |
| 9293 | save_selected_frame (&inf_status->selected_frame_id, |
| 9294 | &inf_status->selected_frame_level); |
| 9295 | |
| 9296 | return inf_status; |
| 9297 | } |
| 9298 | |
| 9299 | /* Restore inferior session state to INF_STATUS. */ |
| 9300 | |
| 9301 | void |
| 9302 | restore_infcall_control_state (struct infcall_control_state *inf_status) |
| 9303 | { |
| 9304 | struct thread_info *tp = inferior_thread (); |
| 9305 | struct inferior *inf = current_inferior (); |
| 9306 | |
| 9307 | if (tp->control.step_resume_breakpoint) |
| 9308 | tp->control.step_resume_breakpoint->disposition = disp_del_at_next_stop; |
| 9309 | |
| 9310 | if (tp->control.exception_resume_breakpoint) |
| 9311 | tp->control.exception_resume_breakpoint->disposition |
| 9312 | = disp_del_at_next_stop; |
| 9313 | |
| 9314 | /* Handle the bpstat_copy of the chain. */ |
| 9315 | bpstat_clear (&tp->control.stop_bpstat); |
| 9316 | |
| 9317 | tp->control = inf_status->thread_control; |
| 9318 | inf->control = inf_status->inferior_control; |
| 9319 | |
| 9320 | /* Other fields: */ |
| 9321 | stop_stack_dummy = inf_status->stop_stack_dummy; |
| 9322 | stopped_by_random_signal = inf_status->stopped_by_random_signal; |
| 9323 | |
| 9324 | if (target_has_stack ()) |
| 9325 | { |
| 9326 | restore_selected_frame (inf_status->selected_frame_id, |
| 9327 | inf_status->selected_frame_level); |
| 9328 | } |
| 9329 | |
| 9330 | delete inf_status; |
| 9331 | } |
| 9332 | |
| 9333 | void |
| 9334 | discard_infcall_control_state (struct infcall_control_state *inf_status) |
| 9335 | { |
| 9336 | if (inf_status->thread_control.step_resume_breakpoint) |
| 9337 | inf_status->thread_control.step_resume_breakpoint->disposition |
| 9338 | = disp_del_at_next_stop; |
| 9339 | |
| 9340 | if (inf_status->thread_control.exception_resume_breakpoint) |
| 9341 | inf_status->thread_control.exception_resume_breakpoint->disposition |
| 9342 | = disp_del_at_next_stop; |
| 9343 | |
| 9344 | /* See save_infcall_control_state for info on stop_bpstat. */ |
| 9345 | bpstat_clear (&inf_status->thread_control.stop_bpstat); |
| 9346 | |
| 9347 | delete inf_status; |
| 9348 | } |
| 9349 | \f |
| 9350 | /* See infrun.h. */ |
| 9351 | |
| 9352 | void |
| 9353 | clear_exit_convenience_vars (void) |
| 9354 | { |
| 9355 | clear_internalvar (lookup_internalvar ("_exitsignal")); |
| 9356 | clear_internalvar (lookup_internalvar ("_exitcode")); |
| 9357 | } |
| 9358 | \f |
| 9359 | |
| 9360 | /* User interface for reverse debugging: |
| 9361 | Set exec-direction / show exec-direction commands |
| 9362 | (returns error unless target implements to_set_exec_direction method). */ |
| 9363 | |
| 9364 | enum exec_direction_kind execution_direction = EXEC_FORWARD; |
| 9365 | static const char exec_forward[] = "forward"; |
| 9366 | static const char exec_reverse[] = "reverse"; |
| 9367 | static const char *exec_direction = exec_forward; |
| 9368 | static const char *const exec_direction_names[] = { |
| 9369 | exec_forward, |
| 9370 | exec_reverse, |
| 9371 | NULL |
| 9372 | }; |
| 9373 | |
| 9374 | static void |
| 9375 | set_exec_direction_func (const char *args, int from_tty, |
| 9376 | struct cmd_list_element *cmd) |
| 9377 | { |
| 9378 | if (target_can_execute_reverse ()) |
| 9379 | { |
| 9380 | if (!strcmp (exec_direction, exec_forward)) |
| 9381 | execution_direction = EXEC_FORWARD; |
| 9382 | else if (!strcmp (exec_direction, exec_reverse)) |
| 9383 | execution_direction = EXEC_REVERSE; |
| 9384 | } |
| 9385 | else |
| 9386 | { |
| 9387 | exec_direction = exec_forward; |
| 9388 | error (_("Target does not support this operation.")); |
| 9389 | } |
| 9390 | } |
| 9391 | |
| 9392 | static void |
| 9393 | show_exec_direction_func (struct ui_file *out, int from_tty, |
| 9394 | struct cmd_list_element *cmd, const char *value) |
| 9395 | { |
| 9396 | switch (execution_direction) { |
| 9397 | case EXEC_FORWARD: |
| 9398 | fprintf_filtered (out, _("Forward.\n")); |
| 9399 | break; |
| 9400 | case EXEC_REVERSE: |
| 9401 | fprintf_filtered (out, _("Reverse.\n")); |
| 9402 | break; |
| 9403 | default: |
| 9404 | internal_error (__FILE__, __LINE__, |
| 9405 | _("bogus execution_direction value: %d"), |
| 9406 | (int) execution_direction); |
| 9407 | } |
| 9408 | } |
| 9409 | |
| 9410 | static void |
| 9411 | show_schedule_multiple (struct ui_file *file, int from_tty, |
| 9412 | struct cmd_list_element *c, const char *value) |
| 9413 | { |
| 9414 | fprintf_filtered (file, _("Resuming the execution of threads " |
| 9415 | "of all processes is %s.\n"), value); |
| 9416 | } |
| 9417 | |
| 9418 | /* Implementation of `siginfo' variable. */ |
| 9419 | |
| 9420 | static const struct internalvar_funcs siginfo_funcs = |
| 9421 | { |
| 9422 | siginfo_make_value, |
| 9423 | NULL, |
| 9424 | NULL |
| 9425 | }; |
| 9426 | |
| 9427 | /* Callback for infrun's target events source. This is marked when a |
| 9428 | thread has a pending status to process. */ |
| 9429 | |
| 9430 | static void |
| 9431 | infrun_async_inferior_event_handler (gdb_client_data data) |
| 9432 | { |
| 9433 | clear_async_event_handler (infrun_async_inferior_event_token); |
| 9434 | inferior_event_handler (INF_REG_EVENT); |
| 9435 | } |
| 9436 | |
| 9437 | #if GDB_SELF_TEST |
| 9438 | namespace selftests |
| 9439 | { |
| 9440 | |
| 9441 | /* Verify that when two threads with the same ptid exist (from two different |
| 9442 | targets) and one of them changes ptid, we only update inferior_ptid if |
| 9443 | it is appropriate. */ |
| 9444 | |
| 9445 | static void |
| 9446 | infrun_thread_ptid_changed () |
| 9447 | { |
| 9448 | gdbarch *arch = current_inferior ()->gdbarch; |
| 9449 | |
| 9450 | /* The thread which inferior_ptid represents changes ptid. */ |
| 9451 | { |
| 9452 | scoped_restore_current_pspace_and_thread restore; |
| 9453 | |
| 9454 | scoped_mock_context<test_target_ops> target1 (arch); |
| 9455 | scoped_mock_context<test_target_ops> target2 (arch); |
| 9456 | target2.mock_inferior.next = &target1.mock_inferior; |
| 9457 | |
| 9458 | ptid_t old_ptid (111, 222); |
| 9459 | ptid_t new_ptid (111, 333); |
| 9460 | |
| 9461 | target1.mock_inferior.pid = old_ptid.pid (); |
| 9462 | target1.mock_thread.ptid = old_ptid; |
| 9463 | target2.mock_inferior.pid = old_ptid.pid (); |
| 9464 | target2.mock_thread.ptid = old_ptid; |
| 9465 | |
| 9466 | auto restore_inferior_ptid = make_scoped_restore (&inferior_ptid, old_ptid); |
| 9467 | set_current_inferior (&target1.mock_inferior); |
| 9468 | |
| 9469 | thread_change_ptid (&target1.mock_target, old_ptid, new_ptid); |
| 9470 | |
| 9471 | gdb_assert (inferior_ptid == new_ptid); |
| 9472 | } |
| 9473 | |
| 9474 | /* A thread with the same ptid as inferior_ptid, but from another target, |
| 9475 | changes ptid. */ |
| 9476 | { |
| 9477 | scoped_restore_current_pspace_and_thread restore; |
| 9478 | |
| 9479 | scoped_mock_context<test_target_ops> target1 (arch); |
| 9480 | scoped_mock_context<test_target_ops> target2 (arch); |
| 9481 | target2.mock_inferior.next = &target1.mock_inferior; |
| 9482 | |
| 9483 | ptid_t old_ptid (111, 222); |
| 9484 | ptid_t new_ptid (111, 333); |
| 9485 | |
| 9486 | target1.mock_inferior.pid = old_ptid.pid (); |
| 9487 | target1.mock_thread.ptid = old_ptid; |
| 9488 | target2.mock_inferior.pid = old_ptid.pid (); |
| 9489 | target2.mock_thread.ptid = old_ptid; |
| 9490 | |
| 9491 | auto restore_inferior_ptid = make_scoped_restore (&inferior_ptid, old_ptid); |
| 9492 | set_current_inferior (&target2.mock_inferior); |
| 9493 | |
| 9494 | thread_change_ptid (&target1.mock_target, old_ptid, new_ptid); |
| 9495 | |
| 9496 | gdb_assert (inferior_ptid == old_ptid); |
| 9497 | } |
| 9498 | } |
| 9499 | |
| 9500 | } /* namespace selftests */ |
| 9501 | |
| 9502 | #endif /* GDB_SELF_TEST */ |
| 9503 | |
| 9504 | void _initialize_infrun (); |
| 9505 | void |
| 9506 | _initialize_infrun () |
| 9507 | { |
| 9508 | struct cmd_list_element *c; |
| 9509 | |
| 9510 | /* Register extra event sources in the event loop. */ |
| 9511 | infrun_async_inferior_event_token |
| 9512 | = create_async_event_handler (infrun_async_inferior_event_handler, NULL, |
| 9513 | "infrun"); |
| 9514 | |
| 9515 | cmd_list_element *info_signals_cmd |
| 9516 | = add_info ("signals", info_signals_command, _("\ |
| 9517 | What debugger does when program gets various signals.\n\ |
| 9518 | Specify a signal as argument to print info on that signal only.")); |
| 9519 | add_info_alias ("handle", info_signals_cmd, 0); |
| 9520 | |
| 9521 | c = add_com ("handle", class_run, handle_command, _("\ |
| 9522 | Specify how to handle signals.\n\ |
| 9523 | Usage: handle SIGNAL [ACTIONS]\n\ |
| 9524 | Args are signals and actions to apply to those signals.\n\ |
| 9525 | If no actions are specified, the current settings for the specified signals\n\ |
| 9526 | will be displayed instead.\n\ |
| 9527 | \n\ |
| 9528 | Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\ |
| 9529 | from 1-15 are allowed for compatibility with old versions of GDB.\n\ |
| 9530 | Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\ |
| 9531 | The special arg \"all\" is recognized to mean all signals except those\n\ |
| 9532 | used by the debugger, typically SIGTRAP and SIGINT.\n\ |
| 9533 | \n\ |
| 9534 | Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\ |
| 9535 | \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\ |
| 9536 | Stop means reenter debugger if this signal happens (implies print).\n\ |
| 9537 | Print means print a message if this signal happens.\n\ |
| 9538 | Pass means let program see this signal; otherwise program doesn't know.\n\ |
| 9539 | Ignore is a synonym for nopass and noignore is a synonym for pass.\n\ |
| 9540 | Pass and Stop may be combined.\n\ |
| 9541 | \n\ |
| 9542 | Multiple signals may be specified. Signal numbers and signal names\n\ |
| 9543 | may be interspersed with actions, with the actions being performed for\n\ |
| 9544 | all signals cumulatively specified.")); |
| 9545 | set_cmd_completer (c, handle_completer); |
| 9546 | |
| 9547 | if (!dbx_commands) |
| 9548 | stop_command = add_cmd ("stop", class_obscure, |
| 9549 | not_just_help_class_command, _("\ |
| 9550 | There is no `stop' command, but you can set a hook on `stop'.\n\ |
| 9551 | This allows you to set a list of commands to be run each time execution\n\ |
| 9552 | of the program stops."), &cmdlist); |
| 9553 | |
| 9554 | add_setshow_boolean_cmd |
| 9555 | ("infrun", class_maintenance, &debug_infrun, |
| 9556 | _("Set inferior debugging."), |
| 9557 | _("Show inferior debugging."), |
| 9558 | _("When non-zero, inferior specific debugging is enabled."), |
| 9559 | NULL, show_debug_infrun, &setdebuglist, &showdebuglist); |
| 9560 | |
| 9561 | add_setshow_boolean_cmd ("non-stop", no_class, |
| 9562 | &non_stop_1, _("\ |
| 9563 | Set whether gdb controls the inferior in non-stop mode."), _("\ |
| 9564 | Show whether gdb controls the inferior in non-stop mode."), _("\ |
| 9565 | When debugging a multi-threaded program and this setting is\n\ |
| 9566 | off (the default, also called all-stop mode), when one thread stops\n\ |
| 9567 | (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\ |
| 9568 | all other threads in the program while you interact with the thread of\n\ |
| 9569 | interest. When you continue or step a thread, you can allow the other\n\ |
| 9570 | threads to run, or have them remain stopped, but while you inspect any\n\ |
| 9571 | thread's state, all threads stop.\n\ |
| 9572 | \n\ |
| 9573 | In non-stop mode, when one thread stops, other threads can continue\n\ |
| 9574 | to run freely. You'll be able to step each thread independently,\n\ |
| 9575 | leave it stopped or free to run as needed."), |
| 9576 | set_non_stop, |
| 9577 | show_non_stop, |
| 9578 | &setlist, |
| 9579 | &showlist); |
| 9580 | |
| 9581 | for (size_t i = 0; i < GDB_SIGNAL_LAST; i++) |
| 9582 | { |
| 9583 | signal_stop[i] = 1; |
| 9584 | signal_print[i] = 1; |
| 9585 | signal_program[i] = 1; |
| 9586 | signal_catch[i] = 0; |
| 9587 | } |
| 9588 | |
| 9589 | /* Signals caused by debugger's own actions should not be given to |
| 9590 | the program afterwards. |
| 9591 | |
| 9592 | Do not deliver GDB_SIGNAL_TRAP by default, except when the user |
| 9593 | explicitly specifies that it should be delivered to the target |
| 9594 | program. Typically, that would occur when a user is debugging a |
| 9595 | target monitor on a simulator: the target monitor sets a |
| 9596 | breakpoint; the simulator encounters this breakpoint and halts |
| 9597 | the simulation handing control to GDB; GDB, noting that the stop |
| 9598 | address doesn't map to any known breakpoint, returns control back |
| 9599 | to the simulator; the simulator then delivers the hardware |
| 9600 | equivalent of a GDB_SIGNAL_TRAP to the program being |
| 9601 | debugged. */ |
| 9602 | signal_program[GDB_SIGNAL_TRAP] = 0; |
| 9603 | signal_program[GDB_SIGNAL_INT] = 0; |
| 9604 | |
| 9605 | /* Signals that are not errors should not normally enter the debugger. */ |
| 9606 | signal_stop[GDB_SIGNAL_ALRM] = 0; |
| 9607 | signal_print[GDB_SIGNAL_ALRM] = 0; |
| 9608 | signal_stop[GDB_SIGNAL_VTALRM] = 0; |
| 9609 | signal_print[GDB_SIGNAL_VTALRM] = 0; |
| 9610 | signal_stop[GDB_SIGNAL_PROF] = 0; |
| 9611 | signal_print[GDB_SIGNAL_PROF] = 0; |
| 9612 | signal_stop[GDB_SIGNAL_CHLD] = 0; |
| 9613 | signal_print[GDB_SIGNAL_CHLD] = 0; |
| 9614 | signal_stop[GDB_SIGNAL_IO] = 0; |
| 9615 | signal_print[GDB_SIGNAL_IO] = 0; |
| 9616 | signal_stop[GDB_SIGNAL_POLL] = 0; |
| 9617 | signal_print[GDB_SIGNAL_POLL] = 0; |
| 9618 | signal_stop[GDB_SIGNAL_URG] = 0; |
| 9619 | signal_print[GDB_SIGNAL_URG] = 0; |
| 9620 | signal_stop[GDB_SIGNAL_WINCH] = 0; |
| 9621 | signal_print[GDB_SIGNAL_WINCH] = 0; |
| 9622 | signal_stop[GDB_SIGNAL_PRIO] = 0; |
| 9623 | signal_print[GDB_SIGNAL_PRIO] = 0; |
| 9624 | |
| 9625 | /* These signals are used internally by user-level thread |
| 9626 | implementations. (See signal(5) on Solaris.) Like the above |
| 9627 | signals, a healthy program receives and handles them as part of |
| 9628 | its normal operation. */ |
| 9629 | signal_stop[GDB_SIGNAL_LWP] = 0; |
| 9630 | signal_print[GDB_SIGNAL_LWP] = 0; |
| 9631 | signal_stop[GDB_SIGNAL_WAITING] = 0; |
| 9632 | signal_print[GDB_SIGNAL_WAITING] = 0; |
| 9633 | signal_stop[GDB_SIGNAL_CANCEL] = 0; |
| 9634 | signal_print[GDB_SIGNAL_CANCEL] = 0; |
| 9635 | signal_stop[GDB_SIGNAL_LIBRT] = 0; |
| 9636 | signal_print[GDB_SIGNAL_LIBRT] = 0; |
| 9637 | |
| 9638 | /* Update cached state. */ |
| 9639 | signal_cache_update (-1); |
| 9640 | |
| 9641 | add_setshow_zinteger_cmd ("stop-on-solib-events", class_support, |
| 9642 | &stop_on_solib_events, _("\ |
| 9643 | Set stopping for shared library events."), _("\ |
| 9644 | Show stopping for shared library events."), _("\ |
| 9645 | If nonzero, gdb will give control to the user when the dynamic linker\n\ |
| 9646 | notifies gdb of shared library events. The most common event of interest\n\ |
| 9647 | to the user would be loading/unloading of a new library."), |
| 9648 | set_stop_on_solib_events, |
| 9649 | show_stop_on_solib_events, |
| 9650 | &setlist, &showlist); |
| 9651 | |
| 9652 | add_setshow_enum_cmd ("follow-fork-mode", class_run, |
| 9653 | follow_fork_mode_kind_names, |
| 9654 | &follow_fork_mode_string, _("\ |
| 9655 | Set debugger response to a program call of fork or vfork."), _("\ |
| 9656 | Show debugger response to a program call of fork or vfork."), _("\ |
| 9657 | A fork or vfork creates a new process. follow-fork-mode can be:\n\ |
| 9658 | parent - the original process is debugged after a fork\n\ |
| 9659 | child - the new process is debugged after a fork\n\ |
| 9660 | The unfollowed process will continue to run.\n\ |
| 9661 | By default, the debugger will follow the parent process."), |
| 9662 | NULL, |
| 9663 | show_follow_fork_mode_string, |
| 9664 | &setlist, &showlist); |
| 9665 | |
| 9666 | add_setshow_enum_cmd ("follow-exec-mode", class_run, |
| 9667 | follow_exec_mode_names, |
| 9668 | &follow_exec_mode_string, _("\ |
| 9669 | Set debugger response to a program call of exec."), _("\ |
| 9670 | Show debugger response to a program call of exec."), _("\ |
| 9671 | An exec call replaces the program image of a process.\n\ |
| 9672 | \n\ |
| 9673 | follow-exec-mode can be:\n\ |
| 9674 | \n\ |
| 9675 | new - the debugger creates a new inferior and rebinds the process\n\ |
| 9676 | to this new inferior. The program the process was running before\n\ |
| 9677 | the exec call can be restarted afterwards by restarting the original\n\ |
| 9678 | inferior.\n\ |
| 9679 | \n\ |
| 9680 | same - the debugger keeps the process bound to the same inferior.\n\ |
| 9681 | The new executable image replaces the previous executable loaded in\n\ |
| 9682 | the inferior. Restarting the inferior after the exec call restarts\n\ |
| 9683 | the executable the process was running after the exec call.\n\ |
| 9684 | \n\ |
| 9685 | By default, the debugger will use the same inferior."), |
| 9686 | NULL, |
| 9687 | show_follow_exec_mode_string, |
| 9688 | &setlist, &showlist); |
| 9689 | |
| 9690 | add_setshow_enum_cmd ("scheduler-locking", class_run, |
| 9691 | scheduler_enums, &scheduler_mode, _("\ |
| 9692 | Set mode for locking scheduler during execution."), _("\ |
| 9693 | Show mode for locking scheduler during execution."), _("\ |
| 9694 | off == no locking (threads may preempt at any time)\n\ |
| 9695 | on == full locking (no thread except the current thread may run)\n\ |
| 9696 | This applies to both normal execution and replay mode.\n\ |
| 9697 | step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\ |
| 9698 | In this mode, other threads may run during other commands.\n\ |
| 9699 | This applies to both normal execution and replay mode.\n\ |
| 9700 | replay == scheduler locked in replay mode and unlocked during normal execution."), |
| 9701 | set_schedlock_func, /* traps on target vector */ |
| 9702 | show_scheduler_mode, |
| 9703 | &setlist, &showlist); |
| 9704 | |
| 9705 | add_setshow_boolean_cmd ("schedule-multiple", class_run, &sched_multi, _("\ |
| 9706 | Set mode for resuming threads of all processes."), _("\ |
| 9707 | Show mode for resuming threads of all processes."), _("\ |
| 9708 | When on, execution commands (such as 'continue' or 'next') resume all\n\ |
| 9709 | threads of all processes. When off (which is the default), execution\n\ |
| 9710 | commands only resume the threads of the current process. The set of\n\ |
| 9711 | threads that are resumed is further refined by the scheduler-locking\n\ |
| 9712 | mode (see help set scheduler-locking)."), |
| 9713 | NULL, |
| 9714 | show_schedule_multiple, |
| 9715 | &setlist, &showlist); |
| 9716 | |
| 9717 | add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\ |
| 9718 | Set mode of the step operation."), _("\ |
| 9719 | Show mode of the step operation."), _("\ |
| 9720 | When set, doing a step over a function without debug line information\n\ |
| 9721 | will stop at the first instruction of that function. Otherwise, the\n\ |
| 9722 | function is skipped and the step command stops at a different source line."), |
| 9723 | NULL, |
| 9724 | show_step_stop_if_no_debug, |
| 9725 | &setlist, &showlist); |
| 9726 | |
| 9727 | add_setshow_auto_boolean_cmd ("displaced-stepping", class_run, |
| 9728 | &can_use_displaced_stepping, _("\ |
| 9729 | Set debugger's willingness to use displaced stepping."), _("\ |
| 9730 | Show debugger's willingness to use displaced stepping."), _("\ |
| 9731 | If on, gdb will use displaced stepping to step over breakpoints if it is\n\ |
| 9732 | supported by the target architecture. If off, gdb will not use displaced\n\ |
| 9733 | stepping to step over breakpoints, even if such is supported by the target\n\ |
| 9734 | architecture. If auto (which is the default), gdb will use displaced stepping\n\ |
| 9735 | if the target architecture supports it and non-stop mode is active, but will not\n\ |
| 9736 | use it in all-stop mode (see help set non-stop)."), |
| 9737 | NULL, |
| 9738 | show_can_use_displaced_stepping, |
| 9739 | &setlist, &showlist); |
| 9740 | |
| 9741 | add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names, |
| 9742 | &exec_direction, _("Set direction of execution.\n\ |
| 9743 | Options are 'forward' or 'reverse'."), |
| 9744 | _("Show direction of execution (forward/reverse)."), |
| 9745 | _("Tells gdb whether to execute forward or backward."), |
| 9746 | set_exec_direction_func, show_exec_direction_func, |
| 9747 | &setlist, &showlist); |
| 9748 | |
| 9749 | /* Set/show detach-on-fork: user-settable mode. */ |
| 9750 | |
| 9751 | add_setshow_boolean_cmd ("detach-on-fork", class_run, &detach_fork, _("\ |
| 9752 | Set whether gdb will detach the child of a fork."), _("\ |
| 9753 | Show whether gdb will detach the child of a fork."), _("\ |
| 9754 | Tells gdb whether to detach the child of a fork."), |
| 9755 | NULL, NULL, &setlist, &showlist); |
| 9756 | |
| 9757 | /* Set/show disable address space randomization mode. */ |
| 9758 | |
| 9759 | add_setshow_boolean_cmd ("disable-randomization", class_support, |
| 9760 | &disable_randomization, _("\ |
| 9761 | Set disabling of debuggee's virtual address space randomization."), _("\ |
| 9762 | Show disabling of debuggee's virtual address space randomization."), _("\ |
| 9763 | When this mode is on (which is the default), randomization of the virtual\n\ |
| 9764 | address space is disabled. Standalone programs run with the randomization\n\ |
| 9765 | enabled by default on some platforms."), |
| 9766 | &set_disable_randomization, |
| 9767 | &show_disable_randomization, |
| 9768 | &setlist, &showlist); |
| 9769 | |
| 9770 | /* ptid initializations */ |
| 9771 | inferior_ptid = null_ptid; |
| 9772 | target_last_wait_ptid = minus_one_ptid; |
| 9773 | |
| 9774 | gdb::observers::thread_ptid_changed.attach (infrun_thread_ptid_changed, |
| 9775 | "infrun"); |
| 9776 | gdb::observers::thread_stop_requested.attach (infrun_thread_stop_requested, |
| 9777 | "infrun"); |
| 9778 | gdb::observers::thread_exit.attach (infrun_thread_thread_exit, "infrun"); |
| 9779 | gdb::observers::inferior_exit.attach (infrun_inferior_exit, "infrun"); |
| 9780 | gdb::observers::inferior_execd.attach (infrun_inferior_execd, "infrun"); |
| 9781 | |
| 9782 | /* Explicitly create without lookup, since that tries to create a |
| 9783 | value with a void typed value, and when we get here, gdbarch |
| 9784 | isn't initialized yet. At this point, we're quite sure there |
| 9785 | isn't another convenience variable of the same name. */ |
| 9786 | create_internalvar_type_lazy ("_siginfo", &siginfo_funcs, NULL); |
| 9787 | |
| 9788 | add_setshow_boolean_cmd ("observer", no_class, |
| 9789 | &observer_mode_1, _("\ |
| 9790 | Set whether gdb controls the inferior in observer mode."), _("\ |
| 9791 | Show whether gdb controls the inferior in observer mode."), _("\ |
| 9792 | In observer mode, GDB can get data from the inferior, but not\n\ |
| 9793 | affect its execution. Registers and memory may not be changed,\n\ |
| 9794 | breakpoints may not be set, and the program cannot be interrupted\n\ |
| 9795 | or signalled."), |
| 9796 | set_observer_mode, |
| 9797 | show_observer_mode, |
| 9798 | &setlist, |
| 9799 | &showlist); |
| 9800 | |
| 9801 | #if GDB_SELF_TEST |
| 9802 | selftests::register_test ("infrun_thread_ptid_changed", |
| 9803 | selftests::infrun_thread_ptid_changed); |
| 9804 | #endif |
| 9805 | } |