| 1 | /* Target-struct-independent code to start (run) and stop an inferior |
| 2 | process. |
| 3 | |
| 4 | Copyright (C) 1986-2015 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 "infrun.h" |
| 23 | #include <ctype.h> |
| 24 | #include "symtab.h" |
| 25 | #include "frame.h" |
| 26 | #include "inferior.h" |
| 27 | #include "breakpoint.h" |
| 28 | #include "gdb_wait.h" |
| 29 | #include "gdbcore.h" |
| 30 | #include "gdbcmd.h" |
| 31 | #include "cli/cli-script.h" |
| 32 | #include "target.h" |
| 33 | #include "gdbthread.h" |
| 34 | #include "annotate.h" |
| 35 | #include "symfile.h" |
| 36 | #include "top.h" |
| 37 | #include <signal.h> |
| 38 | #include "inf-loop.h" |
| 39 | #include "regcache.h" |
| 40 | #include "value.h" |
| 41 | #include "observer.h" |
| 42 | #include "language.h" |
| 43 | #include "solib.h" |
| 44 | #include "main.h" |
| 45 | #include "dictionary.h" |
| 46 | #include "block.h" |
| 47 | #include "mi/mi-common.h" |
| 48 | #include "event-top.h" |
| 49 | #include "record.h" |
| 50 | #include "record-full.h" |
| 51 | #include "inline-frame.h" |
| 52 | #include "jit.h" |
| 53 | #include "tracepoint.h" |
| 54 | #include "continuations.h" |
| 55 | #include "interps.h" |
| 56 | #include "skip.h" |
| 57 | #include "probe.h" |
| 58 | #include "objfiles.h" |
| 59 | #include "completer.h" |
| 60 | #include "target-descriptions.h" |
| 61 | #include "target-dcache.h" |
| 62 | #include "terminal.h" |
| 63 | #include "solist.h" |
| 64 | #include "event-loop.h" |
| 65 | #include "thread-fsm.h" |
| 66 | |
| 67 | /* Prototypes for local functions */ |
| 68 | |
| 69 | static void signals_info (char *, int); |
| 70 | |
| 71 | static void handle_command (char *, int); |
| 72 | |
| 73 | static void sig_print_info (enum gdb_signal); |
| 74 | |
| 75 | static void sig_print_header (void); |
| 76 | |
| 77 | static void resume_cleanups (void *); |
| 78 | |
| 79 | static int hook_stop_stub (void *); |
| 80 | |
| 81 | static int restore_selected_frame (void *); |
| 82 | |
| 83 | static int follow_fork (void); |
| 84 | |
| 85 | static int follow_fork_inferior (int follow_child, int detach_fork); |
| 86 | |
| 87 | static void follow_inferior_reset_breakpoints (void); |
| 88 | |
| 89 | static void set_schedlock_func (char *args, int from_tty, |
| 90 | struct cmd_list_element *c); |
| 91 | |
| 92 | static int currently_stepping (struct thread_info *tp); |
| 93 | |
| 94 | void _initialize_infrun (void); |
| 95 | |
| 96 | void nullify_last_target_wait_ptid (void); |
| 97 | |
| 98 | static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info *); |
| 99 | |
| 100 | static void insert_step_resume_breakpoint_at_caller (struct frame_info *); |
| 101 | |
| 102 | static void insert_longjmp_resume_breakpoint (struct gdbarch *, CORE_ADDR); |
| 103 | |
| 104 | static int maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc); |
| 105 | |
| 106 | /* Asynchronous signal handler registered as event loop source for |
| 107 | when we have pending events ready to be passed to the core. */ |
| 108 | static struct async_event_handler *infrun_async_inferior_event_token; |
| 109 | |
| 110 | /* Stores whether infrun_async was previously enabled or disabled. |
| 111 | Starts off as -1, indicating "never enabled/disabled". */ |
| 112 | static int infrun_is_async = -1; |
| 113 | |
| 114 | /* See infrun.h. */ |
| 115 | |
| 116 | void |
| 117 | infrun_async (int enable) |
| 118 | { |
| 119 | if (infrun_is_async != enable) |
| 120 | { |
| 121 | infrun_is_async = enable; |
| 122 | |
| 123 | if (debug_infrun) |
| 124 | fprintf_unfiltered (gdb_stdlog, |
| 125 | "infrun: infrun_async(%d)\n", |
| 126 | enable); |
| 127 | |
| 128 | if (enable) |
| 129 | mark_async_event_handler (infrun_async_inferior_event_token); |
| 130 | else |
| 131 | clear_async_event_handler (infrun_async_inferior_event_token); |
| 132 | } |
| 133 | } |
| 134 | |
| 135 | /* See infrun.h. */ |
| 136 | |
| 137 | void |
| 138 | mark_infrun_async_event_handler (void) |
| 139 | { |
| 140 | mark_async_event_handler (infrun_async_inferior_event_token); |
| 141 | } |
| 142 | |
| 143 | /* When set, stop the 'step' command if we enter a function which has |
| 144 | no line number information. The normal behavior is that we step |
| 145 | over such function. */ |
| 146 | int step_stop_if_no_debug = 0; |
| 147 | static void |
| 148 | show_step_stop_if_no_debug (struct ui_file *file, int from_tty, |
| 149 | struct cmd_list_element *c, const char *value) |
| 150 | { |
| 151 | fprintf_filtered (file, _("Mode of the step operation is %s.\n"), value); |
| 152 | } |
| 153 | |
| 154 | /* In asynchronous mode, but simulating synchronous execution. */ |
| 155 | |
| 156 | int sync_execution = 0; |
| 157 | |
| 158 | /* proceed and normal_stop use this to notify the user when the |
| 159 | inferior stopped in a different thread than it had been running |
| 160 | in. */ |
| 161 | |
| 162 | static ptid_t previous_inferior_ptid; |
| 163 | |
| 164 | /* If set (default for legacy reasons), when following a fork, GDB |
| 165 | will detach from one of the fork branches, child or parent. |
| 166 | Exactly which branch is detached depends on 'set follow-fork-mode' |
| 167 | setting. */ |
| 168 | |
| 169 | static int detach_fork = 1; |
| 170 | |
| 171 | int debug_displaced = 0; |
| 172 | static void |
| 173 | show_debug_displaced (struct ui_file *file, int from_tty, |
| 174 | struct cmd_list_element *c, const char *value) |
| 175 | { |
| 176 | fprintf_filtered (file, _("Displace stepping debugging is %s.\n"), value); |
| 177 | } |
| 178 | |
| 179 | unsigned int debug_infrun = 0; |
| 180 | static void |
| 181 | show_debug_infrun (struct ui_file *file, int from_tty, |
| 182 | struct cmd_list_element *c, const char *value) |
| 183 | { |
| 184 | fprintf_filtered (file, _("Inferior debugging is %s.\n"), value); |
| 185 | } |
| 186 | |
| 187 | |
| 188 | /* Support for disabling address space randomization. */ |
| 189 | |
| 190 | int disable_randomization = 1; |
| 191 | |
| 192 | static void |
| 193 | show_disable_randomization (struct ui_file *file, int from_tty, |
| 194 | struct cmd_list_element *c, const char *value) |
| 195 | { |
| 196 | if (target_supports_disable_randomization ()) |
| 197 | fprintf_filtered (file, |
| 198 | _("Disabling randomization of debuggee's " |
| 199 | "virtual address space is %s.\n"), |
| 200 | value); |
| 201 | else |
| 202 | fputs_filtered (_("Disabling randomization of debuggee's " |
| 203 | "virtual address space is unsupported on\n" |
| 204 | "this platform.\n"), file); |
| 205 | } |
| 206 | |
| 207 | static void |
| 208 | set_disable_randomization (char *args, int from_tty, |
| 209 | struct cmd_list_element *c) |
| 210 | { |
| 211 | if (!target_supports_disable_randomization ()) |
| 212 | error (_("Disabling randomization of debuggee's " |
| 213 | "virtual address space is unsupported on\n" |
| 214 | "this platform.")); |
| 215 | } |
| 216 | |
| 217 | /* User interface for non-stop mode. */ |
| 218 | |
| 219 | int non_stop = 0; |
| 220 | static int non_stop_1 = 0; |
| 221 | |
| 222 | static void |
| 223 | set_non_stop (char *args, int from_tty, |
| 224 | struct cmd_list_element *c) |
| 225 | { |
| 226 | if (target_has_execution) |
| 227 | { |
| 228 | non_stop_1 = non_stop; |
| 229 | error (_("Cannot change this setting while the inferior is running.")); |
| 230 | } |
| 231 | |
| 232 | non_stop = non_stop_1; |
| 233 | } |
| 234 | |
| 235 | static void |
| 236 | show_non_stop (struct ui_file *file, int from_tty, |
| 237 | struct cmd_list_element *c, const char *value) |
| 238 | { |
| 239 | fprintf_filtered (file, |
| 240 | _("Controlling the inferior in non-stop mode is %s.\n"), |
| 241 | value); |
| 242 | } |
| 243 | |
| 244 | /* "Observer mode" is somewhat like a more extreme version of |
| 245 | non-stop, in which all GDB operations that might affect the |
| 246 | target's execution have been disabled. */ |
| 247 | |
| 248 | int observer_mode = 0; |
| 249 | static int observer_mode_1 = 0; |
| 250 | |
| 251 | static void |
| 252 | set_observer_mode (char *args, int from_tty, |
| 253 | struct cmd_list_element *c) |
| 254 | { |
| 255 | if (target_has_execution) |
| 256 | { |
| 257 | observer_mode_1 = observer_mode; |
| 258 | error (_("Cannot change this setting while the inferior is running.")); |
| 259 | } |
| 260 | |
| 261 | observer_mode = observer_mode_1; |
| 262 | |
| 263 | may_write_registers = !observer_mode; |
| 264 | may_write_memory = !observer_mode; |
| 265 | may_insert_breakpoints = !observer_mode; |
| 266 | may_insert_tracepoints = !observer_mode; |
| 267 | /* We can insert fast tracepoints in or out of observer mode, |
| 268 | but enable them if we're going into this mode. */ |
| 269 | if (observer_mode) |
| 270 | may_insert_fast_tracepoints = 1; |
| 271 | may_stop = !observer_mode; |
| 272 | update_target_permissions (); |
| 273 | |
| 274 | /* Going *into* observer mode we must force non-stop, then |
| 275 | going out we leave it that way. */ |
| 276 | if (observer_mode) |
| 277 | { |
| 278 | pagination_enabled = 0; |
| 279 | non_stop = non_stop_1 = 1; |
| 280 | } |
| 281 | |
| 282 | if (from_tty) |
| 283 | printf_filtered (_("Observer mode is now %s.\n"), |
| 284 | (observer_mode ? "on" : "off")); |
| 285 | } |
| 286 | |
| 287 | static void |
| 288 | show_observer_mode (struct ui_file *file, int from_tty, |
| 289 | struct cmd_list_element *c, const char *value) |
| 290 | { |
| 291 | fprintf_filtered (file, _("Observer mode is %s.\n"), value); |
| 292 | } |
| 293 | |
| 294 | /* This updates the value of observer mode based on changes in |
| 295 | permissions. Note that we are deliberately ignoring the values of |
| 296 | may-write-registers and may-write-memory, since the user may have |
| 297 | reason to enable these during a session, for instance to turn on a |
| 298 | debugging-related global. */ |
| 299 | |
| 300 | void |
| 301 | update_observer_mode (void) |
| 302 | { |
| 303 | int newval; |
| 304 | |
| 305 | newval = (!may_insert_breakpoints |
| 306 | && !may_insert_tracepoints |
| 307 | && may_insert_fast_tracepoints |
| 308 | && !may_stop |
| 309 | && non_stop); |
| 310 | |
| 311 | /* Let the user know if things change. */ |
| 312 | if (newval != observer_mode) |
| 313 | printf_filtered (_("Observer mode is now %s.\n"), |
| 314 | (newval ? "on" : "off")); |
| 315 | |
| 316 | observer_mode = observer_mode_1 = newval; |
| 317 | } |
| 318 | |
| 319 | /* Tables of how to react to signals; the user sets them. */ |
| 320 | |
| 321 | static unsigned char *signal_stop; |
| 322 | static unsigned char *signal_print; |
| 323 | static unsigned char *signal_program; |
| 324 | |
| 325 | /* Table of signals that are registered with "catch signal". A |
| 326 | non-zero entry indicates that the signal is caught by some "catch |
| 327 | signal" command. This has size GDB_SIGNAL_LAST, to accommodate all |
| 328 | signals. */ |
| 329 | static unsigned char *signal_catch; |
| 330 | |
| 331 | /* Table of signals that the target may silently handle. |
| 332 | This is automatically determined from the flags above, |
| 333 | and simply cached here. */ |
| 334 | static unsigned char *signal_pass; |
| 335 | |
| 336 | #define SET_SIGS(nsigs,sigs,flags) \ |
| 337 | do { \ |
| 338 | int signum = (nsigs); \ |
| 339 | while (signum-- > 0) \ |
| 340 | if ((sigs)[signum]) \ |
| 341 | (flags)[signum] = 1; \ |
| 342 | } while (0) |
| 343 | |
| 344 | #define UNSET_SIGS(nsigs,sigs,flags) \ |
| 345 | do { \ |
| 346 | int signum = (nsigs); \ |
| 347 | while (signum-- > 0) \ |
| 348 | if ((sigs)[signum]) \ |
| 349 | (flags)[signum] = 0; \ |
| 350 | } while (0) |
| 351 | |
| 352 | /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of |
| 353 | this function is to avoid exporting `signal_program'. */ |
| 354 | |
| 355 | void |
| 356 | update_signals_program_target (void) |
| 357 | { |
| 358 | target_program_signals ((int) GDB_SIGNAL_LAST, signal_program); |
| 359 | } |
| 360 | |
| 361 | /* Value to pass to target_resume() to cause all threads to resume. */ |
| 362 | |
| 363 | #define RESUME_ALL minus_one_ptid |
| 364 | |
| 365 | /* Command list pointer for the "stop" placeholder. */ |
| 366 | |
| 367 | static struct cmd_list_element *stop_command; |
| 368 | |
| 369 | /* Nonzero if we want to give control to the user when we're notified |
| 370 | of shared library events by the dynamic linker. */ |
| 371 | int stop_on_solib_events; |
| 372 | |
| 373 | /* Enable or disable optional shared library event breakpoints |
| 374 | as appropriate when the above flag is changed. */ |
| 375 | |
| 376 | static void |
| 377 | set_stop_on_solib_events (char *args, int from_tty, struct cmd_list_element *c) |
| 378 | { |
| 379 | update_solib_breakpoints (); |
| 380 | } |
| 381 | |
| 382 | static void |
| 383 | show_stop_on_solib_events (struct ui_file *file, int from_tty, |
| 384 | struct cmd_list_element *c, const char *value) |
| 385 | { |
| 386 | fprintf_filtered (file, _("Stopping for shared library events is %s.\n"), |
| 387 | value); |
| 388 | } |
| 389 | |
| 390 | /* Nonzero means expecting a trace trap |
| 391 | and should stop the inferior and return silently when it happens. */ |
| 392 | |
| 393 | int stop_after_trap; |
| 394 | |
| 395 | /* Nonzero after stop if current stack frame should be printed. */ |
| 396 | |
| 397 | static int stop_print_frame; |
| 398 | |
| 399 | /* This is a cached copy of the pid/waitstatus of the last event |
| 400 | returned by target_wait()/deprecated_target_wait_hook(). This |
| 401 | information is returned by get_last_target_status(). */ |
| 402 | static ptid_t target_last_wait_ptid; |
| 403 | static struct target_waitstatus target_last_waitstatus; |
| 404 | |
| 405 | static void context_switch (ptid_t ptid); |
| 406 | |
| 407 | void init_thread_stepping_state (struct thread_info *tss); |
| 408 | |
| 409 | static const char follow_fork_mode_child[] = "child"; |
| 410 | static const char follow_fork_mode_parent[] = "parent"; |
| 411 | |
| 412 | static const char *const follow_fork_mode_kind_names[] = { |
| 413 | follow_fork_mode_child, |
| 414 | follow_fork_mode_parent, |
| 415 | NULL |
| 416 | }; |
| 417 | |
| 418 | static const char *follow_fork_mode_string = follow_fork_mode_parent; |
| 419 | static void |
| 420 | show_follow_fork_mode_string (struct ui_file *file, int from_tty, |
| 421 | struct cmd_list_element *c, const char *value) |
| 422 | { |
| 423 | fprintf_filtered (file, |
| 424 | _("Debugger response to a program " |
| 425 | "call of fork or vfork is \"%s\".\n"), |
| 426 | value); |
| 427 | } |
| 428 | \f |
| 429 | |
| 430 | /* Handle changes to the inferior list based on the type of fork, |
| 431 | which process is being followed, and whether the other process |
| 432 | should be detached. On entry inferior_ptid must be the ptid of |
| 433 | the fork parent. At return inferior_ptid is the ptid of the |
| 434 | followed inferior. */ |
| 435 | |
| 436 | static int |
| 437 | follow_fork_inferior (int follow_child, int detach_fork) |
| 438 | { |
| 439 | int has_vforked; |
| 440 | ptid_t parent_ptid, child_ptid; |
| 441 | |
| 442 | has_vforked = (inferior_thread ()->pending_follow.kind |
| 443 | == TARGET_WAITKIND_VFORKED); |
| 444 | parent_ptid = inferior_ptid; |
| 445 | child_ptid = inferior_thread ()->pending_follow.value.related_pid; |
| 446 | |
| 447 | if (has_vforked |
| 448 | && !non_stop /* Non-stop always resumes both branches. */ |
| 449 | && (!target_is_async_p () || sync_execution) |
| 450 | && !(follow_child || detach_fork || sched_multi)) |
| 451 | { |
| 452 | /* The parent stays blocked inside the vfork syscall until the |
| 453 | child execs or exits. If we don't let the child run, then |
| 454 | the parent stays blocked. If we're telling the parent to run |
| 455 | in the foreground, the user will not be able to ctrl-c to get |
| 456 | back the terminal, effectively hanging the debug session. */ |
| 457 | fprintf_filtered (gdb_stderr, _("\ |
| 458 | Can not resume the parent process over vfork in the foreground while\n\ |
| 459 | holding the child stopped. Try \"set detach-on-fork\" or \ |
| 460 | \"set schedule-multiple\".\n")); |
| 461 | /* FIXME output string > 80 columns. */ |
| 462 | return 1; |
| 463 | } |
| 464 | |
| 465 | if (!follow_child) |
| 466 | { |
| 467 | /* Detach new forked process? */ |
| 468 | if (detach_fork) |
| 469 | { |
| 470 | struct cleanup *old_chain; |
| 471 | |
| 472 | /* Before detaching from the child, remove all breakpoints |
| 473 | from it. If we forked, then this has already been taken |
| 474 | care of by infrun.c. If we vforked however, any |
| 475 | breakpoint inserted in the parent is visible in the |
| 476 | child, even those added while stopped in a vfork |
| 477 | catchpoint. This will remove the breakpoints from the |
| 478 | parent also, but they'll be reinserted below. */ |
| 479 | if (has_vforked) |
| 480 | { |
| 481 | /* Keep breakpoints list in sync. */ |
| 482 | remove_breakpoints_pid (ptid_get_pid (inferior_ptid)); |
| 483 | } |
| 484 | |
| 485 | if (info_verbose || debug_infrun) |
| 486 | { |
| 487 | /* Ensure that we have a process ptid. */ |
| 488 | ptid_t process_ptid = pid_to_ptid (ptid_get_pid (child_ptid)); |
| 489 | |
| 490 | target_terminal_ours_for_output (); |
| 491 | fprintf_filtered (gdb_stdlog, |
| 492 | _("Detaching after %s from child %s.\n"), |
| 493 | has_vforked ? "vfork" : "fork", |
| 494 | target_pid_to_str (process_ptid)); |
| 495 | } |
| 496 | } |
| 497 | else |
| 498 | { |
| 499 | struct inferior *parent_inf, *child_inf; |
| 500 | struct cleanup *old_chain; |
| 501 | |
| 502 | /* Add process to GDB's tables. */ |
| 503 | child_inf = add_inferior (ptid_get_pid (child_ptid)); |
| 504 | |
| 505 | parent_inf = current_inferior (); |
| 506 | child_inf->attach_flag = parent_inf->attach_flag; |
| 507 | copy_terminal_info (child_inf, parent_inf); |
| 508 | child_inf->gdbarch = parent_inf->gdbarch; |
| 509 | copy_inferior_target_desc_info (child_inf, parent_inf); |
| 510 | |
| 511 | old_chain = save_inferior_ptid (); |
| 512 | save_current_program_space (); |
| 513 | |
| 514 | inferior_ptid = child_ptid; |
| 515 | add_thread (inferior_ptid); |
| 516 | child_inf->symfile_flags = SYMFILE_NO_READ; |
| 517 | |
| 518 | /* If this is a vfork child, then the address-space is |
| 519 | shared with the parent. */ |
| 520 | if (has_vforked) |
| 521 | { |
| 522 | child_inf->pspace = parent_inf->pspace; |
| 523 | child_inf->aspace = parent_inf->aspace; |
| 524 | |
| 525 | /* The parent will be frozen until the child is done |
| 526 | with the shared region. Keep track of the |
| 527 | parent. */ |
| 528 | child_inf->vfork_parent = parent_inf; |
| 529 | child_inf->pending_detach = 0; |
| 530 | parent_inf->vfork_child = child_inf; |
| 531 | parent_inf->pending_detach = 0; |
| 532 | } |
| 533 | else |
| 534 | { |
| 535 | child_inf->aspace = new_address_space (); |
| 536 | child_inf->pspace = add_program_space (child_inf->aspace); |
| 537 | child_inf->removable = 1; |
| 538 | set_current_program_space (child_inf->pspace); |
| 539 | clone_program_space (child_inf->pspace, parent_inf->pspace); |
| 540 | |
| 541 | /* Let the shared library layer (e.g., solib-svr4) learn |
| 542 | about this new process, relocate the cloned exec, pull |
| 543 | in shared libraries, and install the solib event |
| 544 | breakpoint. If a "cloned-VM" event was propagated |
| 545 | better throughout the core, this wouldn't be |
| 546 | required. */ |
| 547 | solib_create_inferior_hook (0); |
| 548 | } |
| 549 | |
| 550 | do_cleanups (old_chain); |
| 551 | } |
| 552 | |
| 553 | if (has_vforked) |
| 554 | { |
| 555 | struct inferior *parent_inf; |
| 556 | |
| 557 | parent_inf = current_inferior (); |
| 558 | |
| 559 | /* If we detached from the child, then we have to be careful |
| 560 | to not insert breakpoints in the parent until the child |
| 561 | is done with the shared memory region. However, if we're |
| 562 | staying attached to the child, then we can and should |
| 563 | insert breakpoints, so that we can debug it. A |
| 564 | subsequent child exec or exit is enough to know when does |
| 565 | the child stops using the parent's address space. */ |
| 566 | parent_inf->waiting_for_vfork_done = detach_fork; |
| 567 | parent_inf->pspace->breakpoints_not_allowed = detach_fork; |
| 568 | } |
| 569 | } |
| 570 | else |
| 571 | { |
| 572 | /* Follow the child. */ |
| 573 | struct inferior *parent_inf, *child_inf; |
| 574 | struct program_space *parent_pspace; |
| 575 | |
| 576 | if (info_verbose || debug_infrun) |
| 577 | { |
| 578 | target_terminal_ours_for_output (); |
| 579 | fprintf_filtered (gdb_stdlog, |
| 580 | _("Attaching after %s %s to child %s.\n"), |
| 581 | target_pid_to_str (parent_ptid), |
| 582 | has_vforked ? "vfork" : "fork", |
| 583 | target_pid_to_str (child_ptid)); |
| 584 | } |
| 585 | |
| 586 | /* Add the new inferior first, so that the target_detach below |
| 587 | doesn't unpush the target. */ |
| 588 | |
| 589 | child_inf = add_inferior (ptid_get_pid (child_ptid)); |
| 590 | |
| 591 | parent_inf = current_inferior (); |
| 592 | child_inf->attach_flag = parent_inf->attach_flag; |
| 593 | copy_terminal_info (child_inf, parent_inf); |
| 594 | child_inf->gdbarch = parent_inf->gdbarch; |
| 595 | copy_inferior_target_desc_info (child_inf, parent_inf); |
| 596 | |
| 597 | parent_pspace = parent_inf->pspace; |
| 598 | |
| 599 | /* If we're vforking, we want to hold on to the parent until the |
| 600 | child exits or execs. At child exec or exit time we can |
| 601 | remove the old breakpoints from the parent and detach or |
| 602 | resume debugging it. Otherwise, detach the parent now; we'll |
| 603 | want to reuse it's program/address spaces, but we can't set |
| 604 | them to the child before removing breakpoints from the |
| 605 | parent, otherwise, the breakpoints module could decide to |
| 606 | remove breakpoints from the wrong process (since they'd be |
| 607 | assigned to the same address space). */ |
| 608 | |
| 609 | if (has_vforked) |
| 610 | { |
| 611 | gdb_assert (child_inf->vfork_parent == NULL); |
| 612 | gdb_assert (parent_inf->vfork_child == NULL); |
| 613 | child_inf->vfork_parent = parent_inf; |
| 614 | child_inf->pending_detach = 0; |
| 615 | parent_inf->vfork_child = child_inf; |
| 616 | parent_inf->pending_detach = detach_fork; |
| 617 | parent_inf->waiting_for_vfork_done = 0; |
| 618 | } |
| 619 | else if (detach_fork) |
| 620 | { |
| 621 | if (info_verbose || debug_infrun) |
| 622 | { |
| 623 | /* Ensure that we have a process ptid. */ |
| 624 | ptid_t process_ptid = pid_to_ptid (ptid_get_pid (child_ptid)); |
| 625 | |
| 626 | target_terminal_ours_for_output (); |
| 627 | fprintf_filtered (gdb_stdlog, |
| 628 | _("Detaching after fork from " |
| 629 | "child %s.\n"), |
| 630 | target_pid_to_str (process_ptid)); |
| 631 | } |
| 632 | |
| 633 | target_detach (NULL, 0); |
| 634 | } |
| 635 | |
| 636 | /* Note that the detach above makes PARENT_INF dangling. */ |
| 637 | |
| 638 | /* Add the child thread to the appropriate lists, and switch to |
| 639 | this new thread, before cloning the program space, and |
| 640 | informing the solib layer about this new process. */ |
| 641 | |
| 642 | inferior_ptid = child_ptid; |
| 643 | add_thread (inferior_ptid); |
| 644 | |
| 645 | /* If this is a vfork child, then the address-space is shared |
| 646 | with the parent. If we detached from the parent, then we can |
| 647 | reuse the parent's program/address spaces. */ |
| 648 | if (has_vforked || detach_fork) |
| 649 | { |
| 650 | child_inf->pspace = parent_pspace; |
| 651 | child_inf->aspace = child_inf->pspace->aspace; |
| 652 | } |
| 653 | else |
| 654 | { |
| 655 | child_inf->aspace = new_address_space (); |
| 656 | child_inf->pspace = add_program_space (child_inf->aspace); |
| 657 | child_inf->removable = 1; |
| 658 | child_inf->symfile_flags = SYMFILE_NO_READ; |
| 659 | set_current_program_space (child_inf->pspace); |
| 660 | clone_program_space (child_inf->pspace, parent_pspace); |
| 661 | |
| 662 | /* Let the shared library layer (e.g., solib-svr4) learn |
| 663 | about this new process, relocate the cloned exec, pull in |
| 664 | shared libraries, and install the solib event breakpoint. |
| 665 | If a "cloned-VM" event was propagated better throughout |
| 666 | the core, this wouldn't be required. */ |
| 667 | solib_create_inferior_hook (0); |
| 668 | } |
| 669 | } |
| 670 | |
| 671 | return target_follow_fork (follow_child, detach_fork); |
| 672 | } |
| 673 | |
| 674 | /* Tell the target to follow the fork we're stopped at. Returns true |
| 675 | if the inferior should be resumed; false, if the target for some |
| 676 | reason decided it's best not to resume. */ |
| 677 | |
| 678 | static int |
| 679 | follow_fork (void) |
| 680 | { |
| 681 | int follow_child = (follow_fork_mode_string == follow_fork_mode_child); |
| 682 | int should_resume = 1; |
| 683 | struct thread_info *tp; |
| 684 | |
| 685 | /* Copy user stepping state to the new inferior thread. FIXME: the |
| 686 | followed fork child thread should have a copy of most of the |
| 687 | parent thread structure's run control related fields, not just these. |
| 688 | Initialized to avoid "may be used uninitialized" warnings from gcc. */ |
| 689 | struct breakpoint *step_resume_breakpoint = NULL; |
| 690 | struct breakpoint *exception_resume_breakpoint = NULL; |
| 691 | CORE_ADDR step_range_start = 0; |
| 692 | CORE_ADDR step_range_end = 0; |
| 693 | struct frame_id step_frame_id = { 0 }; |
| 694 | struct interp *command_interp = NULL; |
| 695 | |
| 696 | if (!non_stop) |
| 697 | { |
| 698 | ptid_t wait_ptid; |
| 699 | struct target_waitstatus wait_status; |
| 700 | |
| 701 | /* Get the last target status returned by target_wait(). */ |
| 702 | get_last_target_status (&wait_ptid, &wait_status); |
| 703 | |
| 704 | /* If not stopped at a fork event, then there's nothing else to |
| 705 | do. */ |
| 706 | if (wait_status.kind != TARGET_WAITKIND_FORKED |
| 707 | && wait_status.kind != TARGET_WAITKIND_VFORKED) |
| 708 | return 1; |
| 709 | |
| 710 | /* Check if we switched over from WAIT_PTID, since the event was |
| 711 | reported. */ |
| 712 | if (!ptid_equal (wait_ptid, minus_one_ptid) |
| 713 | && !ptid_equal (inferior_ptid, wait_ptid)) |
| 714 | { |
| 715 | /* We did. Switch back to WAIT_PTID thread, to tell the |
| 716 | target to follow it (in either direction). We'll |
| 717 | afterwards refuse to resume, and inform the user what |
| 718 | happened. */ |
| 719 | switch_to_thread (wait_ptid); |
| 720 | should_resume = 0; |
| 721 | } |
| 722 | } |
| 723 | |
| 724 | tp = inferior_thread (); |
| 725 | |
| 726 | /* If there were any forks/vforks that were caught and are now to be |
| 727 | followed, then do so now. */ |
| 728 | switch (tp->pending_follow.kind) |
| 729 | { |
| 730 | case TARGET_WAITKIND_FORKED: |
| 731 | case TARGET_WAITKIND_VFORKED: |
| 732 | { |
| 733 | ptid_t parent, child; |
| 734 | |
| 735 | /* If the user did a next/step, etc, over a fork call, |
| 736 | preserve the stepping state in the fork child. */ |
| 737 | if (follow_child && should_resume) |
| 738 | { |
| 739 | step_resume_breakpoint = clone_momentary_breakpoint |
| 740 | (tp->control.step_resume_breakpoint); |
| 741 | step_range_start = tp->control.step_range_start; |
| 742 | step_range_end = tp->control.step_range_end; |
| 743 | step_frame_id = tp->control.step_frame_id; |
| 744 | exception_resume_breakpoint |
| 745 | = clone_momentary_breakpoint (tp->control.exception_resume_breakpoint); |
| 746 | command_interp = tp->control.command_interp; |
| 747 | |
| 748 | /* For now, delete the parent's sr breakpoint, otherwise, |
| 749 | parent/child sr breakpoints are considered duplicates, |
| 750 | and the child version will not be installed. Remove |
| 751 | this when the breakpoints module becomes aware of |
| 752 | inferiors and address spaces. */ |
| 753 | delete_step_resume_breakpoint (tp); |
| 754 | tp->control.step_range_start = 0; |
| 755 | tp->control.step_range_end = 0; |
| 756 | tp->control.step_frame_id = null_frame_id; |
| 757 | delete_exception_resume_breakpoint (tp); |
| 758 | tp->control.command_interp = NULL; |
| 759 | } |
| 760 | |
| 761 | parent = inferior_ptid; |
| 762 | child = tp->pending_follow.value.related_pid; |
| 763 | |
| 764 | /* Set up inferior(s) as specified by the caller, and tell the |
| 765 | target to do whatever is necessary to follow either parent |
| 766 | or child. */ |
| 767 | if (follow_fork_inferior (follow_child, detach_fork)) |
| 768 | { |
| 769 | /* Target refused to follow, or there's some other reason |
| 770 | we shouldn't resume. */ |
| 771 | should_resume = 0; |
| 772 | } |
| 773 | else |
| 774 | { |
| 775 | /* This pending follow fork event is now handled, one way |
| 776 | or another. The previous selected thread may be gone |
| 777 | from the lists by now, but if it is still around, need |
| 778 | to clear the pending follow request. */ |
| 779 | tp = find_thread_ptid (parent); |
| 780 | if (tp) |
| 781 | tp->pending_follow.kind = TARGET_WAITKIND_SPURIOUS; |
| 782 | |
| 783 | /* This makes sure we don't try to apply the "Switched |
| 784 | over from WAIT_PID" logic above. */ |
| 785 | nullify_last_target_wait_ptid (); |
| 786 | |
| 787 | /* If we followed the child, switch to it... */ |
| 788 | if (follow_child) |
| 789 | { |
| 790 | switch_to_thread (child); |
| 791 | |
| 792 | /* ... and preserve the stepping state, in case the |
| 793 | user was stepping over the fork call. */ |
| 794 | if (should_resume) |
| 795 | { |
| 796 | tp = inferior_thread (); |
| 797 | tp->control.step_resume_breakpoint |
| 798 | = step_resume_breakpoint; |
| 799 | tp->control.step_range_start = step_range_start; |
| 800 | tp->control.step_range_end = step_range_end; |
| 801 | tp->control.step_frame_id = step_frame_id; |
| 802 | tp->control.exception_resume_breakpoint |
| 803 | = exception_resume_breakpoint; |
| 804 | tp->control.command_interp = command_interp; |
| 805 | } |
| 806 | else |
| 807 | { |
| 808 | /* If we get here, it was because we're trying to |
| 809 | resume from a fork catchpoint, but, the user |
| 810 | has switched threads away from the thread that |
| 811 | forked. In that case, the resume command |
| 812 | issued is most likely not applicable to the |
| 813 | child, so just warn, and refuse to resume. */ |
| 814 | warning (_("Not resuming: switched threads " |
| 815 | "before following fork child.")); |
| 816 | } |
| 817 | |
| 818 | /* Reset breakpoints in the child as appropriate. */ |
| 819 | follow_inferior_reset_breakpoints (); |
| 820 | } |
| 821 | else |
| 822 | switch_to_thread (parent); |
| 823 | } |
| 824 | } |
| 825 | break; |
| 826 | case TARGET_WAITKIND_SPURIOUS: |
| 827 | /* Nothing to follow. */ |
| 828 | break; |
| 829 | default: |
| 830 | internal_error (__FILE__, __LINE__, |
| 831 | "Unexpected pending_follow.kind %d\n", |
| 832 | tp->pending_follow.kind); |
| 833 | break; |
| 834 | } |
| 835 | |
| 836 | return should_resume; |
| 837 | } |
| 838 | |
| 839 | static void |
| 840 | follow_inferior_reset_breakpoints (void) |
| 841 | { |
| 842 | struct thread_info *tp = inferior_thread (); |
| 843 | |
| 844 | /* Was there a step_resume breakpoint? (There was if the user |
| 845 | did a "next" at the fork() call.) If so, explicitly reset its |
| 846 | thread number. Cloned step_resume breakpoints are disabled on |
| 847 | creation, so enable it here now that it is associated with the |
| 848 | correct thread. |
| 849 | |
| 850 | step_resumes are a form of bp that are made to be per-thread. |
| 851 | Since we created the step_resume bp when the parent process |
| 852 | was being debugged, and now are switching to the child process, |
| 853 | from the breakpoint package's viewpoint, that's a switch of |
| 854 | "threads". We must update the bp's notion of which thread |
| 855 | it is for, or it'll be ignored when it triggers. */ |
| 856 | |
| 857 | if (tp->control.step_resume_breakpoint) |
| 858 | { |
| 859 | breakpoint_re_set_thread (tp->control.step_resume_breakpoint); |
| 860 | tp->control.step_resume_breakpoint->loc->enabled = 1; |
| 861 | } |
| 862 | |
| 863 | /* Treat exception_resume breakpoints like step_resume breakpoints. */ |
| 864 | if (tp->control.exception_resume_breakpoint) |
| 865 | { |
| 866 | breakpoint_re_set_thread (tp->control.exception_resume_breakpoint); |
| 867 | tp->control.exception_resume_breakpoint->loc->enabled = 1; |
| 868 | } |
| 869 | |
| 870 | /* Reinsert all breakpoints in the child. The user may have set |
| 871 | breakpoints after catching the fork, in which case those |
| 872 | were never set in the child, but only in the parent. This makes |
| 873 | sure the inserted breakpoints match the breakpoint list. */ |
| 874 | |
| 875 | breakpoint_re_set (); |
| 876 | insert_breakpoints (); |
| 877 | } |
| 878 | |
| 879 | /* The child has exited or execed: resume threads of the parent the |
| 880 | user wanted to be executing. */ |
| 881 | |
| 882 | static int |
| 883 | proceed_after_vfork_done (struct thread_info *thread, |
| 884 | void *arg) |
| 885 | { |
| 886 | int pid = * (int *) arg; |
| 887 | |
| 888 | if (ptid_get_pid (thread->ptid) == pid |
| 889 | && is_running (thread->ptid) |
| 890 | && !is_executing (thread->ptid) |
| 891 | && !thread->stop_requested |
| 892 | && thread->suspend.stop_signal == GDB_SIGNAL_0) |
| 893 | { |
| 894 | if (debug_infrun) |
| 895 | fprintf_unfiltered (gdb_stdlog, |
| 896 | "infrun: resuming vfork parent thread %s\n", |
| 897 | target_pid_to_str (thread->ptid)); |
| 898 | |
| 899 | switch_to_thread (thread->ptid); |
| 900 | clear_proceed_status (0); |
| 901 | proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT); |
| 902 | } |
| 903 | |
| 904 | return 0; |
| 905 | } |
| 906 | |
| 907 | /* Called whenever we notice an exec or exit event, to handle |
| 908 | detaching or resuming a vfork parent. */ |
| 909 | |
| 910 | static void |
| 911 | handle_vfork_child_exec_or_exit (int exec) |
| 912 | { |
| 913 | struct inferior *inf = current_inferior (); |
| 914 | |
| 915 | if (inf->vfork_parent) |
| 916 | { |
| 917 | int resume_parent = -1; |
| 918 | |
| 919 | /* This exec or exit marks the end of the shared memory region |
| 920 | between the parent and the child. If the user wanted to |
| 921 | detach from the parent, now is the time. */ |
| 922 | |
| 923 | if (inf->vfork_parent->pending_detach) |
| 924 | { |
| 925 | struct thread_info *tp; |
| 926 | struct cleanup *old_chain; |
| 927 | struct program_space *pspace; |
| 928 | struct address_space *aspace; |
| 929 | |
| 930 | /* follow-fork child, detach-on-fork on. */ |
| 931 | |
| 932 | inf->vfork_parent->pending_detach = 0; |
| 933 | |
| 934 | if (!exec) |
| 935 | { |
| 936 | /* If we're handling a child exit, then inferior_ptid |
| 937 | points at the inferior's pid, not to a thread. */ |
| 938 | old_chain = save_inferior_ptid (); |
| 939 | save_current_program_space (); |
| 940 | save_current_inferior (); |
| 941 | } |
| 942 | else |
| 943 | old_chain = save_current_space_and_thread (); |
| 944 | |
| 945 | /* We're letting loose of the parent. */ |
| 946 | tp = any_live_thread_of_process (inf->vfork_parent->pid); |
| 947 | switch_to_thread (tp->ptid); |
| 948 | |
| 949 | /* We're about to detach from the parent, which implicitly |
| 950 | removes breakpoints from its address space. There's a |
| 951 | catch here: we want to reuse the spaces for the child, |
| 952 | but, parent/child are still sharing the pspace at this |
| 953 | point, although the exec in reality makes the kernel give |
| 954 | the child a fresh set of new pages. The problem here is |
| 955 | that the breakpoints module being unaware of this, would |
| 956 | likely chose the child process to write to the parent |
| 957 | address space. Swapping the child temporarily away from |
| 958 | the spaces has the desired effect. Yes, this is "sort |
| 959 | of" a hack. */ |
| 960 | |
| 961 | pspace = inf->pspace; |
| 962 | aspace = inf->aspace; |
| 963 | inf->aspace = NULL; |
| 964 | inf->pspace = NULL; |
| 965 | |
| 966 | if (debug_infrun || info_verbose) |
| 967 | { |
| 968 | target_terminal_ours_for_output (); |
| 969 | |
| 970 | if (exec) |
| 971 | { |
| 972 | fprintf_filtered (gdb_stdlog, |
| 973 | _("Detaching vfork parent process " |
| 974 | "%d after child exec.\n"), |
| 975 | inf->vfork_parent->pid); |
| 976 | } |
| 977 | else |
| 978 | { |
| 979 | fprintf_filtered (gdb_stdlog, |
| 980 | _("Detaching vfork parent process " |
| 981 | "%d after child exit.\n"), |
| 982 | inf->vfork_parent->pid); |
| 983 | } |
| 984 | } |
| 985 | |
| 986 | target_detach (NULL, 0); |
| 987 | |
| 988 | /* Put it back. */ |
| 989 | inf->pspace = pspace; |
| 990 | inf->aspace = aspace; |
| 991 | |
| 992 | do_cleanups (old_chain); |
| 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 = add_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 = inf->vfork_parent->pid; |
| 1004 | |
| 1005 | /* Break the bonds. */ |
| 1006 | inf->vfork_parent->vfork_child = NULL; |
| 1007 | } |
| 1008 | else |
| 1009 | { |
| 1010 | struct cleanup *old_chain; |
| 1011 | struct program_space *pspace; |
| 1012 | |
| 1013 | /* If this is a vfork child exiting, then the pspace and |
| 1014 | aspaces were shared with the parent. Since we're |
| 1015 | reporting the process exit, we'll be mourning all that is |
| 1016 | found in the address space, and switching to null_ptid, |
| 1017 | preparing to start a new inferior. But, since we don't |
| 1018 | want to clobber the parent's address/program spaces, we |
| 1019 | go ahead and create a new one for this exiting |
| 1020 | inferior. */ |
| 1021 | |
| 1022 | /* Switch to null_ptid, so that clone_program_space doesn't want |
| 1023 | to read the selected frame of a dead process. */ |
| 1024 | old_chain = save_inferior_ptid (); |
| 1025 | inferior_ptid = null_ptid; |
| 1026 | |
| 1027 | /* This inferior is dead, so avoid giving the breakpoints |
| 1028 | module the option to write through to it (cloning a |
| 1029 | program space resets breakpoints). */ |
| 1030 | inf->aspace = NULL; |
| 1031 | inf->pspace = NULL; |
| 1032 | pspace = add_program_space (maybe_new_address_space ()); |
| 1033 | set_current_program_space (pspace); |
| 1034 | inf->removable = 1; |
| 1035 | inf->symfile_flags = SYMFILE_NO_READ; |
| 1036 | clone_program_space (pspace, inf->vfork_parent->pspace); |
| 1037 | inf->pspace = pspace; |
| 1038 | inf->aspace = pspace->aspace; |
| 1039 | |
| 1040 | /* Put back inferior_ptid. We'll continue mourning this |
| 1041 | inferior. */ |
| 1042 | do_cleanups (old_chain); |
| 1043 | |
| 1044 | resume_parent = inf->vfork_parent->pid; |
| 1045 | /* Break the bonds. */ |
| 1046 | inf->vfork_parent->vfork_child = NULL; |
| 1047 | } |
| 1048 | |
| 1049 | inf->vfork_parent = NULL; |
| 1050 | |
| 1051 | gdb_assert (current_program_space == inf->pspace); |
| 1052 | |
| 1053 | if (non_stop && resume_parent != -1) |
| 1054 | { |
| 1055 | /* If the user wanted the parent to be running, let it go |
| 1056 | free now. */ |
| 1057 | struct cleanup *old_chain = make_cleanup_restore_current_thread (); |
| 1058 | |
| 1059 | if (debug_infrun) |
| 1060 | fprintf_unfiltered (gdb_stdlog, |
| 1061 | "infrun: resuming vfork parent process %d\n", |
| 1062 | resume_parent); |
| 1063 | |
| 1064 | iterate_over_threads (proceed_after_vfork_done, &resume_parent); |
| 1065 | |
| 1066 | do_cleanups (old_chain); |
| 1067 | } |
| 1068 | } |
| 1069 | } |
| 1070 | |
| 1071 | /* Enum strings for "set|show follow-exec-mode". */ |
| 1072 | |
| 1073 | static const char follow_exec_mode_new[] = "new"; |
| 1074 | static const char follow_exec_mode_same[] = "same"; |
| 1075 | static const char *const follow_exec_mode_names[] = |
| 1076 | { |
| 1077 | follow_exec_mode_new, |
| 1078 | follow_exec_mode_same, |
| 1079 | NULL, |
| 1080 | }; |
| 1081 | |
| 1082 | static const char *follow_exec_mode_string = follow_exec_mode_same; |
| 1083 | static void |
| 1084 | show_follow_exec_mode_string (struct ui_file *file, int from_tty, |
| 1085 | struct cmd_list_element *c, const char *value) |
| 1086 | { |
| 1087 | fprintf_filtered (file, _("Follow exec mode is \"%s\".\n"), value); |
| 1088 | } |
| 1089 | |
| 1090 | /* EXECD_PATHNAME is assumed to be non-NULL. */ |
| 1091 | |
| 1092 | static void |
| 1093 | follow_exec (ptid_t ptid, char *execd_pathname) |
| 1094 | { |
| 1095 | struct thread_info *th, *tmp; |
| 1096 | struct inferior *inf = current_inferior (); |
| 1097 | int pid = ptid_get_pid (ptid); |
| 1098 | ptid_t process_ptid; |
| 1099 | |
| 1100 | /* This is an exec event that we actually wish to pay attention to. |
| 1101 | Refresh our symbol table to the newly exec'd program, remove any |
| 1102 | momentary bp's, etc. |
| 1103 | |
| 1104 | If there are breakpoints, they aren't really inserted now, |
| 1105 | since the exec() transformed our inferior into a fresh set |
| 1106 | of instructions. |
| 1107 | |
| 1108 | We want to preserve symbolic breakpoints on the list, since |
| 1109 | we have hopes that they can be reset after the new a.out's |
| 1110 | symbol table is read. |
| 1111 | |
| 1112 | However, any "raw" breakpoints must be removed from the list |
| 1113 | (e.g., the solib bp's), since their address is probably invalid |
| 1114 | now. |
| 1115 | |
| 1116 | And, we DON'T want to call delete_breakpoints() here, since |
| 1117 | that may write the bp's "shadow contents" (the instruction |
| 1118 | value that was overwritten witha TRAP instruction). Since |
| 1119 | we now have a new a.out, those shadow contents aren't valid. */ |
| 1120 | |
| 1121 | mark_breakpoints_out (); |
| 1122 | |
| 1123 | /* The target reports the exec event to the main thread, even if |
| 1124 | some other thread does the exec, and even if the main thread was |
| 1125 | stopped or already gone. We may still have non-leader threads of |
| 1126 | the process on our list. E.g., on targets that don't have thread |
| 1127 | exit events (like remote); or on native Linux in non-stop mode if |
| 1128 | there were only two threads in the inferior and the non-leader |
| 1129 | one is the one that execs (and nothing forces an update of the |
| 1130 | thread list up to here). When debugging remotely, it's best to |
| 1131 | avoid extra traffic, when possible, so avoid syncing the thread |
| 1132 | list with the target, and instead go ahead and delete all threads |
| 1133 | of the process but one that reported the event. Note this must |
| 1134 | be done before calling update_breakpoints_after_exec, as |
| 1135 | otherwise clearing the threads' resources would reference stale |
| 1136 | thread breakpoints -- it may have been one of these threads that |
| 1137 | stepped across the exec. We could just clear their stepping |
| 1138 | states, but as long as we're iterating, might as well delete |
| 1139 | them. Deleting them now rather than at the next user-visible |
| 1140 | stop provides a nicer sequence of events for user and MI |
| 1141 | notifications. */ |
| 1142 | ALL_THREADS_SAFE (th, tmp) |
| 1143 | if (ptid_get_pid (th->ptid) == pid && !ptid_equal (th->ptid, ptid)) |
| 1144 | delete_thread (th->ptid); |
| 1145 | |
| 1146 | /* We also need to clear any left over stale state for the |
| 1147 | leader/event thread. E.g., if there was any step-resume |
| 1148 | breakpoint or similar, it's gone now. We cannot truly |
| 1149 | step-to-next statement through an exec(). */ |
| 1150 | th = inferior_thread (); |
| 1151 | th->control.step_resume_breakpoint = NULL; |
| 1152 | th->control.exception_resume_breakpoint = NULL; |
| 1153 | th->control.single_step_breakpoints = NULL; |
| 1154 | th->control.step_range_start = 0; |
| 1155 | th->control.step_range_end = 0; |
| 1156 | |
| 1157 | /* The user may have had the main thread held stopped in the |
| 1158 | previous image (e.g., schedlock on, or non-stop). Release |
| 1159 | it now. */ |
| 1160 | th->stop_requested = 0; |
| 1161 | |
| 1162 | update_breakpoints_after_exec (); |
| 1163 | |
| 1164 | /* What is this a.out's name? */ |
| 1165 | process_ptid = pid_to_ptid (pid); |
| 1166 | printf_unfiltered (_("%s is executing new program: %s\n"), |
| 1167 | target_pid_to_str (process_ptid), |
| 1168 | execd_pathname); |
| 1169 | |
| 1170 | /* We've followed the inferior through an exec. Therefore, the |
| 1171 | inferior has essentially been killed & reborn. */ |
| 1172 | |
| 1173 | gdb_flush (gdb_stdout); |
| 1174 | |
| 1175 | breakpoint_init_inferior (inf_execd); |
| 1176 | |
| 1177 | if (*gdb_sysroot != '\0') |
| 1178 | { |
| 1179 | char *name = exec_file_find (execd_pathname, NULL); |
| 1180 | |
| 1181 | execd_pathname = alloca (strlen (name) + 1); |
| 1182 | strcpy (execd_pathname, name); |
| 1183 | xfree (name); |
| 1184 | } |
| 1185 | |
| 1186 | /* Reset the shared library package. This ensures that we get a |
| 1187 | shlib event when the child reaches "_start", at which point the |
| 1188 | dld will have had a chance to initialize the child. */ |
| 1189 | /* Also, loading a symbol file below may trigger symbol lookups, and |
| 1190 | we don't want those to be satisfied by the libraries of the |
| 1191 | previous incarnation of this process. */ |
| 1192 | no_shared_libraries (NULL, 0); |
| 1193 | |
| 1194 | if (follow_exec_mode_string == follow_exec_mode_new) |
| 1195 | { |
| 1196 | /* The user wants to keep the old inferior and program spaces |
| 1197 | around. Create a new fresh one, and switch to it. */ |
| 1198 | |
| 1199 | /* Do exit processing for the original inferior before adding |
| 1200 | the new inferior so we don't have two active inferiors with |
| 1201 | the same ptid, which can confuse find_inferior_ptid. */ |
| 1202 | exit_inferior_num_silent (current_inferior ()->num); |
| 1203 | |
| 1204 | inf = add_inferior_with_spaces (); |
| 1205 | inf->pid = pid; |
| 1206 | target_follow_exec (inf, execd_pathname); |
| 1207 | |
| 1208 | set_current_inferior (inf); |
| 1209 | set_current_program_space (inf->pspace); |
| 1210 | add_thread (ptid); |
| 1211 | } |
| 1212 | else |
| 1213 | { |
| 1214 | /* The old description may no longer be fit for the new image. |
| 1215 | E.g, a 64-bit process exec'ed a 32-bit process. Clear the |
| 1216 | old description; we'll read a new one below. No need to do |
| 1217 | this on "follow-exec-mode new", as the old inferior stays |
| 1218 | around (its description is later cleared/refetched on |
| 1219 | restart). */ |
| 1220 | target_clear_description (); |
| 1221 | } |
| 1222 | |
| 1223 | gdb_assert (current_program_space == inf->pspace); |
| 1224 | |
| 1225 | /* That a.out is now the one to use. */ |
| 1226 | exec_file_attach (execd_pathname, 0); |
| 1227 | |
| 1228 | /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE |
| 1229 | (Position Independent Executable) main symbol file will get applied by |
| 1230 | solib_create_inferior_hook below. breakpoint_re_set would fail to insert |
| 1231 | the breakpoints with the zero displacement. */ |
| 1232 | |
| 1233 | symbol_file_add (execd_pathname, |
| 1234 | (inf->symfile_flags |
| 1235 | | SYMFILE_MAINLINE | SYMFILE_DEFER_BP_RESET), |
| 1236 | NULL, 0); |
| 1237 | |
| 1238 | if ((inf->symfile_flags & SYMFILE_NO_READ) == 0) |
| 1239 | set_initial_language (); |
| 1240 | |
| 1241 | /* If the target can specify a description, read it. Must do this |
| 1242 | after flipping to the new executable (because the target supplied |
| 1243 | description must be compatible with the executable's |
| 1244 | architecture, and the old executable may e.g., be 32-bit, while |
| 1245 | the new one 64-bit), and before anything involving memory or |
| 1246 | registers. */ |
| 1247 | target_find_description (); |
| 1248 | |
| 1249 | solib_create_inferior_hook (0); |
| 1250 | |
| 1251 | jit_inferior_created_hook (); |
| 1252 | |
| 1253 | breakpoint_re_set (); |
| 1254 | |
| 1255 | /* Reinsert all breakpoints. (Those which were symbolic have |
| 1256 | been reset to the proper address in the new a.out, thanks |
| 1257 | to symbol_file_command...). */ |
| 1258 | insert_breakpoints (); |
| 1259 | |
| 1260 | /* The next resume of this inferior should bring it to the shlib |
| 1261 | startup breakpoints. (If the user had also set bp's on |
| 1262 | "main" from the old (parent) process, then they'll auto- |
| 1263 | matically get reset there in the new process.). */ |
| 1264 | } |
| 1265 | |
| 1266 | /* The queue of threads that need to do a step-over operation to get |
| 1267 | past e.g., a breakpoint. What technique is used to step over the |
| 1268 | breakpoint/watchpoint does not matter -- all threads end up in the |
| 1269 | same queue, to maintain rough temporal order of execution, in order |
| 1270 | to avoid starvation, otherwise, we could e.g., find ourselves |
| 1271 | constantly stepping the same couple threads past their breakpoints |
| 1272 | over and over, if the single-step finish fast enough. */ |
| 1273 | struct thread_info *step_over_queue_head; |
| 1274 | |
| 1275 | /* Bit flags indicating what the thread needs to step over. */ |
| 1276 | |
| 1277 | enum step_over_what |
| 1278 | { |
| 1279 | /* Step over a breakpoint. */ |
| 1280 | STEP_OVER_BREAKPOINT = 1, |
| 1281 | |
| 1282 | /* Step past a non-continuable watchpoint, in order to let the |
| 1283 | instruction execute so we can evaluate the watchpoint |
| 1284 | expression. */ |
| 1285 | STEP_OVER_WATCHPOINT = 2 |
| 1286 | }; |
| 1287 | |
| 1288 | /* Info about an instruction that is being stepped over. */ |
| 1289 | |
| 1290 | struct step_over_info |
| 1291 | { |
| 1292 | /* If we're stepping past a breakpoint, this is the address space |
| 1293 | and address of the instruction the breakpoint is set at. We'll |
| 1294 | skip inserting all breakpoints here. Valid iff ASPACE is |
| 1295 | non-NULL. */ |
| 1296 | struct address_space *aspace; |
| 1297 | CORE_ADDR address; |
| 1298 | |
| 1299 | /* The instruction being stepped over triggers a nonsteppable |
| 1300 | watchpoint. If true, we'll skip inserting watchpoints. */ |
| 1301 | int nonsteppable_watchpoint_p; |
| 1302 | }; |
| 1303 | |
| 1304 | /* The step-over info of the location that is being stepped over. |
| 1305 | |
| 1306 | Note that with async/breakpoint always-inserted mode, a user might |
| 1307 | set a new breakpoint/watchpoint/etc. exactly while a breakpoint is |
| 1308 | being stepped over. As setting a new breakpoint inserts all |
| 1309 | breakpoints, we need to make sure the breakpoint being stepped over |
| 1310 | isn't inserted then. We do that by only clearing the step-over |
| 1311 | info when the step-over is actually finished (or aborted). |
| 1312 | |
| 1313 | Presently GDB can only step over one breakpoint at any given time. |
| 1314 | Given threads that can't run code in the same address space as the |
| 1315 | breakpoint's can't really miss the breakpoint, GDB could be taught |
| 1316 | to step-over at most one breakpoint per address space (so this info |
| 1317 | could move to the address space object if/when GDB is extended). |
| 1318 | The set of breakpoints being stepped over will normally be much |
| 1319 | smaller than the set of all breakpoints, so a flag in the |
| 1320 | breakpoint location structure would be wasteful. A separate list |
| 1321 | also saves complexity and run-time, as otherwise we'd have to go |
| 1322 | through all breakpoint locations clearing their flag whenever we |
| 1323 | start a new sequence. Similar considerations weigh against storing |
| 1324 | this info in the thread object. Plus, not all step overs actually |
| 1325 | have breakpoint locations -- e.g., stepping past a single-step |
| 1326 | breakpoint, or stepping to complete a non-continuable |
| 1327 | watchpoint. */ |
| 1328 | static struct step_over_info step_over_info; |
| 1329 | |
| 1330 | /* Record the address of the breakpoint/instruction we're currently |
| 1331 | stepping over. */ |
| 1332 | |
| 1333 | static void |
| 1334 | set_step_over_info (struct address_space *aspace, CORE_ADDR address, |
| 1335 | int nonsteppable_watchpoint_p) |
| 1336 | { |
| 1337 | step_over_info.aspace = aspace; |
| 1338 | step_over_info.address = address; |
| 1339 | step_over_info.nonsteppable_watchpoint_p = nonsteppable_watchpoint_p; |
| 1340 | } |
| 1341 | |
| 1342 | /* Called when we're not longer stepping over a breakpoint / an |
| 1343 | instruction, so all breakpoints are free to be (re)inserted. */ |
| 1344 | |
| 1345 | static void |
| 1346 | clear_step_over_info (void) |
| 1347 | { |
| 1348 | if (debug_infrun) |
| 1349 | fprintf_unfiltered (gdb_stdlog, |
| 1350 | "infrun: clear_step_over_info\n"); |
| 1351 | step_over_info.aspace = NULL; |
| 1352 | step_over_info.address = 0; |
| 1353 | step_over_info.nonsteppable_watchpoint_p = 0; |
| 1354 | } |
| 1355 | |
| 1356 | /* See infrun.h. */ |
| 1357 | |
| 1358 | int |
| 1359 | stepping_past_instruction_at (struct address_space *aspace, |
| 1360 | CORE_ADDR address) |
| 1361 | { |
| 1362 | return (step_over_info.aspace != NULL |
| 1363 | && breakpoint_address_match (aspace, address, |
| 1364 | step_over_info.aspace, |
| 1365 | step_over_info.address)); |
| 1366 | } |
| 1367 | |
| 1368 | /* See infrun.h. */ |
| 1369 | |
| 1370 | int |
| 1371 | stepping_past_nonsteppable_watchpoint (void) |
| 1372 | { |
| 1373 | return step_over_info.nonsteppable_watchpoint_p; |
| 1374 | } |
| 1375 | |
| 1376 | /* Returns true if step-over info is valid. */ |
| 1377 | |
| 1378 | static int |
| 1379 | step_over_info_valid_p (void) |
| 1380 | { |
| 1381 | return (step_over_info.aspace != NULL |
| 1382 | || stepping_past_nonsteppable_watchpoint ()); |
| 1383 | } |
| 1384 | |
| 1385 | \f |
| 1386 | /* Displaced stepping. */ |
| 1387 | |
| 1388 | /* In non-stop debugging mode, we must take special care to manage |
| 1389 | breakpoints properly; in particular, the traditional strategy for |
| 1390 | stepping a thread past a breakpoint it has hit is unsuitable. |
| 1391 | 'Displaced stepping' is a tactic for stepping one thread past a |
| 1392 | breakpoint it has hit while ensuring that other threads running |
| 1393 | concurrently will hit the breakpoint as they should. |
| 1394 | |
| 1395 | The traditional way to step a thread T off a breakpoint in a |
| 1396 | multi-threaded program in all-stop mode is as follows: |
| 1397 | |
| 1398 | a0) Initially, all threads are stopped, and breakpoints are not |
| 1399 | inserted. |
| 1400 | a1) We single-step T, leaving breakpoints uninserted. |
| 1401 | a2) We insert breakpoints, and resume all threads. |
| 1402 | |
| 1403 | In non-stop debugging, however, this strategy is unsuitable: we |
| 1404 | don't want to have to stop all threads in the system in order to |
| 1405 | continue or step T past a breakpoint. Instead, we use displaced |
| 1406 | stepping: |
| 1407 | |
| 1408 | n0) Initially, T is stopped, other threads are running, and |
| 1409 | breakpoints are inserted. |
| 1410 | n1) We copy the instruction "under" the breakpoint to a separate |
| 1411 | location, outside the main code stream, making any adjustments |
| 1412 | to the instruction, register, and memory state as directed by |
| 1413 | T's architecture. |
| 1414 | n2) We single-step T over the instruction at its new location. |
| 1415 | n3) We adjust the resulting register and memory state as directed |
| 1416 | by T's architecture. This includes resetting T's PC to point |
| 1417 | back into the main instruction stream. |
| 1418 | n4) We resume T. |
| 1419 | |
| 1420 | This approach depends on the following gdbarch methods: |
| 1421 | |
| 1422 | - gdbarch_max_insn_length and gdbarch_displaced_step_location |
| 1423 | indicate where to copy the instruction, and how much space must |
| 1424 | be reserved there. We use these in step n1. |
| 1425 | |
| 1426 | - gdbarch_displaced_step_copy_insn copies a instruction to a new |
| 1427 | address, and makes any necessary adjustments to the instruction, |
| 1428 | register contents, and memory. We use this in step n1. |
| 1429 | |
| 1430 | - gdbarch_displaced_step_fixup adjusts registers and memory after |
| 1431 | we have successfuly single-stepped the instruction, to yield the |
| 1432 | same effect the instruction would have had if we had executed it |
| 1433 | at its original address. We use this in step n3. |
| 1434 | |
| 1435 | - gdbarch_displaced_step_free_closure provides cleanup. |
| 1436 | |
| 1437 | The gdbarch_displaced_step_copy_insn and |
| 1438 | gdbarch_displaced_step_fixup functions must be written so that |
| 1439 | copying an instruction with gdbarch_displaced_step_copy_insn, |
| 1440 | single-stepping across the copied instruction, and then applying |
| 1441 | gdbarch_displaced_insn_fixup should have the same effects on the |
| 1442 | thread's memory and registers as stepping the instruction in place |
| 1443 | would have. Exactly which responsibilities fall to the copy and |
| 1444 | which fall to the fixup is up to the author of those functions. |
| 1445 | |
| 1446 | See the comments in gdbarch.sh for details. |
| 1447 | |
| 1448 | Note that displaced stepping and software single-step cannot |
| 1449 | currently be used in combination, although with some care I think |
| 1450 | they could be made to. Software single-step works by placing |
| 1451 | breakpoints on all possible subsequent instructions; if the |
| 1452 | displaced instruction is a PC-relative jump, those breakpoints |
| 1453 | could fall in very strange places --- on pages that aren't |
| 1454 | executable, or at addresses that are not proper instruction |
| 1455 | boundaries. (We do generally let other threads run while we wait |
| 1456 | to hit the software single-step breakpoint, and they might |
| 1457 | encounter such a corrupted instruction.) One way to work around |
| 1458 | this would be to have gdbarch_displaced_step_copy_insn fully |
| 1459 | simulate the effect of PC-relative instructions (and return NULL) |
| 1460 | on architectures that use software single-stepping. |
| 1461 | |
| 1462 | In non-stop mode, we can have independent and simultaneous step |
| 1463 | requests, so more than one thread may need to simultaneously step |
| 1464 | over a breakpoint. The current implementation assumes there is |
| 1465 | only one scratch space per process. In this case, we have to |
| 1466 | serialize access to the scratch space. If thread A wants to step |
| 1467 | over a breakpoint, but we are currently waiting for some other |
| 1468 | thread to complete a displaced step, we leave thread A stopped and |
| 1469 | place it in the displaced_step_request_queue. Whenever a displaced |
| 1470 | step finishes, we pick the next thread in the queue and start a new |
| 1471 | displaced step operation on it. See displaced_step_prepare and |
| 1472 | displaced_step_fixup for details. */ |
| 1473 | |
| 1474 | /* Per-inferior displaced stepping state. */ |
| 1475 | struct displaced_step_inferior_state |
| 1476 | { |
| 1477 | /* Pointer to next in linked list. */ |
| 1478 | struct displaced_step_inferior_state *next; |
| 1479 | |
| 1480 | /* The process this displaced step state refers to. */ |
| 1481 | int pid; |
| 1482 | |
| 1483 | /* True if preparing a displaced step ever failed. If so, we won't |
| 1484 | try displaced stepping for this inferior again. */ |
| 1485 | int failed_before; |
| 1486 | |
| 1487 | /* If this is not null_ptid, this is the thread carrying out a |
| 1488 | displaced single-step in process PID. This thread's state will |
| 1489 | require fixing up once it has completed its step. */ |
| 1490 | ptid_t step_ptid; |
| 1491 | |
| 1492 | /* The architecture the thread had when we stepped it. */ |
| 1493 | struct gdbarch *step_gdbarch; |
| 1494 | |
| 1495 | /* The closure provided gdbarch_displaced_step_copy_insn, to be used |
| 1496 | for post-step cleanup. */ |
| 1497 | struct displaced_step_closure *step_closure; |
| 1498 | |
| 1499 | /* The address of the original instruction, and the copy we |
| 1500 | made. */ |
| 1501 | CORE_ADDR step_original, step_copy; |
| 1502 | |
| 1503 | /* Saved contents of copy area. */ |
| 1504 | gdb_byte *step_saved_copy; |
| 1505 | }; |
| 1506 | |
| 1507 | /* The list of states of processes involved in displaced stepping |
| 1508 | presently. */ |
| 1509 | static struct displaced_step_inferior_state *displaced_step_inferior_states; |
| 1510 | |
| 1511 | /* Get the displaced stepping state of process PID. */ |
| 1512 | |
| 1513 | static struct displaced_step_inferior_state * |
| 1514 | get_displaced_stepping_state (int pid) |
| 1515 | { |
| 1516 | struct displaced_step_inferior_state *state; |
| 1517 | |
| 1518 | for (state = displaced_step_inferior_states; |
| 1519 | state != NULL; |
| 1520 | state = state->next) |
| 1521 | if (state->pid == pid) |
| 1522 | return state; |
| 1523 | |
| 1524 | return NULL; |
| 1525 | } |
| 1526 | |
| 1527 | /* Returns true if any inferior has a thread doing a displaced |
| 1528 | step. */ |
| 1529 | |
| 1530 | static int |
| 1531 | displaced_step_in_progress_any_inferior (void) |
| 1532 | { |
| 1533 | struct displaced_step_inferior_state *state; |
| 1534 | |
| 1535 | for (state = displaced_step_inferior_states; |
| 1536 | state != NULL; |
| 1537 | state = state->next) |
| 1538 | if (!ptid_equal (state->step_ptid, null_ptid)) |
| 1539 | return 1; |
| 1540 | |
| 1541 | return 0; |
| 1542 | } |
| 1543 | |
| 1544 | /* Return true if process PID has a thread doing a displaced step. */ |
| 1545 | |
| 1546 | static int |
| 1547 | displaced_step_in_progress (int pid) |
| 1548 | { |
| 1549 | struct displaced_step_inferior_state *displaced; |
| 1550 | |
| 1551 | displaced = get_displaced_stepping_state (pid); |
| 1552 | if (displaced != NULL && !ptid_equal (displaced->step_ptid, null_ptid)) |
| 1553 | return 1; |
| 1554 | |
| 1555 | return 0; |
| 1556 | } |
| 1557 | |
| 1558 | /* Add a new displaced stepping state for process PID to the displaced |
| 1559 | stepping state list, or return a pointer to an already existing |
| 1560 | entry, if it already exists. Never returns NULL. */ |
| 1561 | |
| 1562 | static struct displaced_step_inferior_state * |
| 1563 | add_displaced_stepping_state (int pid) |
| 1564 | { |
| 1565 | struct displaced_step_inferior_state *state; |
| 1566 | |
| 1567 | for (state = displaced_step_inferior_states; |
| 1568 | state != NULL; |
| 1569 | state = state->next) |
| 1570 | if (state->pid == pid) |
| 1571 | return state; |
| 1572 | |
| 1573 | state = XCNEW (struct displaced_step_inferior_state); |
| 1574 | state->pid = pid; |
| 1575 | state->next = displaced_step_inferior_states; |
| 1576 | displaced_step_inferior_states = state; |
| 1577 | |
| 1578 | return state; |
| 1579 | } |
| 1580 | |
| 1581 | /* If inferior is in displaced stepping, and ADDR equals to starting address |
| 1582 | of copy area, return corresponding displaced_step_closure. Otherwise, |
| 1583 | return NULL. */ |
| 1584 | |
| 1585 | struct displaced_step_closure* |
| 1586 | get_displaced_step_closure_by_addr (CORE_ADDR addr) |
| 1587 | { |
| 1588 | struct displaced_step_inferior_state *displaced |
| 1589 | = get_displaced_stepping_state (ptid_get_pid (inferior_ptid)); |
| 1590 | |
| 1591 | /* If checking the mode of displaced instruction in copy area. */ |
| 1592 | if (displaced && !ptid_equal (displaced->step_ptid, null_ptid) |
| 1593 | && (displaced->step_copy == addr)) |
| 1594 | return displaced->step_closure; |
| 1595 | |
| 1596 | return NULL; |
| 1597 | } |
| 1598 | |
| 1599 | /* Remove the displaced stepping state of process PID. */ |
| 1600 | |
| 1601 | static void |
| 1602 | remove_displaced_stepping_state (int pid) |
| 1603 | { |
| 1604 | struct displaced_step_inferior_state *it, **prev_next_p; |
| 1605 | |
| 1606 | gdb_assert (pid != 0); |
| 1607 | |
| 1608 | it = displaced_step_inferior_states; |
| 1609 | prev_next_p = &displaced_step_inferior_states; |
| 1610 | while (it) |
| 1611 | { |
| 1612 | if (it->pid == pid) |
| 1613 | { |
| 1614 | *prev_next_p = it->next; |
| 1615 | xfree (it); |
| 1616 | return; |
| 1617 | } |
| 1618 | |
| 1619 | prev_next_p = &it->next; |
| 1620 | it = *prev_next_p; |
| 1621 | } |
| 1622 | } |
| 1623 | |
| 1624 | static void |
| 1625 | infrun_inferior_exit (struct inferior *inf) |
| 1626 | { |
| 1627 | remove_displaced_stepping_state (inf->pid); |
| 1628 | } |
| 1629 | |
| 1630 | /* If ON, and the architecture supports it, GDB will use displaced |
| 1631 | stepping to step over breakpoints. If OFF, or if the architecture |
| 1632 | doesn't support it, GDB will instead use the traditional |
| 1633 | hold-and-step approach. If AUTO (which is the default), GDB will |
| 1634 | decide which technique to use to step over breakpoints depending on |
| 1635 | which of all-stop or non-stop mode is active --- displaced stepping |
| 1636 | in non-stop mode; hold-and-step in all-stop mode. */ |
| 1637 | |
| 1638 | static enum auto_boolean can_use_displaced_stepping = AUTO_BOOLEAN_AUTO; |
| 1639 | |
| 1640 | static void |
| 1641 | show_can_use_displaced_stepping (struct ui_file *file, int from_tty, |
| 1642 | struct cmd_list_element *c, |
| 1643 | const char *value) |
| 1644 | { |
| 1645 | if (can_use_displaced_stepping == AUTO_BOOLEAN_AUTO) |
| 1646 | fprintf_filtered (file, |
| 1647 | _("Debugger's willingness to use displaced stepping " |
| 1648 | "to step over breakpoints is %s (currently %s).\n"), |
| 1649 | value, target_is_non_stop_p () ? "on" : "off"); |
| 1650 | else |
| 1651 | fprintf_filtered (file, |
| 1652 | _("Debugger's willingness to use displaced stepping " |
| 1653 | "to step over breakpoints is %s.\n"), value); |
| 1654 | } |
| 1655 | |
| 1656 | /* Return non-zero if displaced stepping can/should be used to step |
| 1657 | over breakpoints of thread TP. */ |
| 1658 | |
| 1659 | static int |
| 1660 | use_displaced_stepping (struct thread_info *tp) |
| 1661 | { |
| 1662 | struct regcache *regcache = get_thread_regcache (tp->ptid); |
| 1663 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 1664 | struct displaced_step_inferior_state *displaced_state; |
| 1665 | |
| 1666 | displaced_state = get_displaced_stepping_state (ptid_get_pid (tp->ptid)); |
| 1667 | |
| 1668 | return (((can_use_displaced_stepping == AUTO_BOOLEAN_AUTO |
| 1669 | && target_is_non_stop_p ()) |
| 1670 | || can_use_displaced_stepping == AUTO_BOOLEAN_TRUE) |
| 1671 | && gdbarch_displaced_step_copy_insn_p (gdbarch) |
| 1672 | && find_record_target () == NULL |
| 1673 | && (displaced_state == NULL |
| 1674 | || !displaced_state->failed_before)); |
| 1675 | } |
| 1676 | |
| 1677 | /* Clean out any stray displaced stepping state. */ |
| 1678 | static void |
| 1679 | displaced_step_clear (struct displaced_step_inferior_state *displaced) |
| 1680 | { |
| 1681 | /* Indicate that there is no cleanup pending. */ |
| 1682 | displaced->step_ptid = null_ptid; |
| 1683 | |
| 1684 | if (displaced->step_closure) |
| 1685 | { |
| 1686 | gdbarch_displaced_step_free_closure (displaced->step_gdbarch, |
| 1687 | displaced->step_closure); |
| 1688 | displaced->step_closure = NULL; |
| 1689 | } |
| 1690 | } |
| 1691 | |
| 1692 | static void |
| 1693 | displaced_step_clear_cleanup (void *arg) |
| 1694 | { |
| 1695 | struct displaced_step_inferior_state *state = arg; |
| 1696 | |
| 1697 | displaced_step_clear (state); |
| 1698 | } |
| 1699 | |
| 1700 | /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */ |
| 1701 | void |
| 1702 | displaced_step_dump_bytes (struct ui_file *file, |
| 1703 | const gdb_byte *buf, |
| 1704 | size_t len) |
| 1705 | { |
| 1706 | int i; |
| 1707 | |
| 1708 | for (i = 0; i < len; i++) |
| 1709 | fprintf_unfiltered (file, "%02x ", buf[i]); |
| 1710 | fputs_unfiltered ("\n", file); |
| 1711 | } |
| 1712 | |
| 1713 | /* Prepare to single-step, using displaced stepping. |
| 1714 | |
| 1715 | Note that we cannot use displaced stepping when we have a signal to |
| 1716 | deliver. If we have a signal to deliver and an instruction to step |
| 1717 | over, then after the step, there will be no indication from the |
| 1718 | target whether the thread entered a signal handler or ignored the |
| 1719 | signal and stepped over the instruction successfully --- both cases |
| 1720 | result in a simple SIGTRAP. In the first case we mustn't do a |
| 1721 | fixup, and in the second case we must --- but we can't tell which. |
| 1722 | Comments in the code for 'random signals' in handle_inferior_event |
| 1723 | explain how we handle this case instead. |
| 1724 | |
| 1725 | Returns 1 if preparing was successful -- this thread is going to be |
| 1726 | stepped now; 0 if displaced stepping this thread got queued; or -1 |
| 1727 | if this instruction can't be displaced stepped. */ |
| 1728 | |
| 1729 | static int |
| 1730 | displaced_step_prepare_throw (ptid_t ptid) |
| 1731 | { |
| 1732 | struct cleanup *old_cleanups, *ignore_cleanups; |
| 1733 | struct thread_info *tp = find_thread_ptid (ptid); |
| 1734 | struct regcache *regcache = get_thread_regcache (ptid); |
| 1735 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 1736 | CORE_ADDR original, copy; |
| 1737 | ULONGEST len; |
| 1738 | struct displaced_step_closure *closure; |
| 1739 | struct displaced_step_inferior_state *displaced; |
| 1740 | int status; |
| 1741 | |
| 1742 | /* We should never reach this function if the architecture does not |
| 1743 | support displaced stepping. */ |
| 1744 | gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch)); |
| 1745 | |
| 1746 | /* Nor if the thread isn't meant to step over a breakpoint. */ |
| 1747 | gdb_assert (tp->control.trap_expected); |
| 1748 | |
| 1749 | /* Disable range stepping while executing in the scratch pad. We |
| 1750 | want a single-step even if executing the displaced instruction in |
| 1751 | the scratch buffer lands within the stepping range (e.g., a |
| 1752 | jump/branch). */ |
| 1753 | tp->control.may_range_step = 0; |
| 1754 | |
| 1755 | /* We have to displaced step one thread at a time, as we only have |
| 1756 | access to a single scratch space per inferior. */ |
| 1757 | |
| 1758 | displaced = add_displaced_stepping_state (ptid_get_pid (ptid)); |
| 1759 | |
| 1760 | if (!ptid_equal (displaced->step_ptid, null_ptid)) |
| 1761 | { |
| 1762 | /* Already waiting for a displaced step to finish. Defer this |
| 1763 | request and place in queue. */ |
| 1764 | |
| 1765 | if (debug_displaced) |
| 1766 | fprintf_unfiltered (gdb_stdlog, |
| 1767 | "displaced: deferring step of %s\n", |
| 1768 | target_pid_to_str (ptid)); |
| 1769 | |
| 1770 | thread_step_over_chain_enqueue (tp); |
| 1771 | return 0; |
| 1772 | } |
| 1773 | else |
| 1774 | { |
| 1775 | if (debug_displaced) |
| 1776 | fprintf_unfiltered (gdb_stdlog, |
| 1777 | "displaced: stepping %s now\n", |
| 1778 | target_pid_to_str (ptid)); |
| 1779 | } |
| 1780 | |
| 1781 | displaced_step_clear (displaced); |
| 1782 | |
| 1783 | old_cleanups = save_inferior_ptid (); |
| 1784 | inferior_ptid = ptid; |
| 1785 | |
| 1786 | original = regcache_read_pc (regcache); |
| 1787 | |
| 1788 | copy = gdbarch_displaced_step_location (gdbarch); |
| 1789 | len = gdbarch_max_insn_length (gdbarch); |
| 1790 | |
| 1791 | /* Save the original contents of the copy area. */ |
| 1792 | displaced->step_saved_copy = xmalloc (len); |
| 1793 | ignore_cleanups = make_cleanup (free_current_contents, |
| 1794 | &displaced->step_saved_copy); |
| 1795 | status = target_read_memory (copy, displaced->step_saved_copy, len); |
| 1796 | if (status != 0) |
| 1797 | throw_error (MEMORY_ERROR, |
| 1798 | _("Error accessing memory address %s (%s) for " |
| 1799 | "displaced-stepping scratch space."), |
| 1800 | paddress (gdbarch, copy), safe_strerror (status)); |
| 1801 | if (debug_displaced) |
| 1802 | { |
| 1803 | fprintf_unfiltered (gdb_stdlog, "displaced: saved %s: ", |
| 1804 | paddress (gdbarch, copy)); |
| 1805 | displaced_step_dump_bytes (gdb_stdlog, |
| 1806 | displaced->step_saved_copy, |
| 1807 | len); |
| 1808 | }; |
| 1809 | |
| 1810 | closure = gdbarch_displaced_step_copy_insn (gdbarch, |
| 1811 | original, copy, regcache); |
| 1812 | if (closure == NULL) |
| 1813 | { |
| 1814 | /* The architecture doesn't know how or want to displaced step |
| 1815 | this instruction or instruction sequence. Fallback to |
| 1816 | stepping over the breakpoint in-line. */ |
| 1817 | do_cleanups (old_cleanups); |
| 1818 | return -1; |
| 1819 | } |
| 1820 | |
| 1821 | /* Save the information we need to fix things up if the step |
| 1822 | succeeds. */ |
| 1823 | displaced->step_ptid = ptid; |
| 1824 | displaced->step_gdbarch = gdbarch; |
| 1825 | displaced->step_closure = closure; |
| 1826 | displaced->step_original = original; |
| 1827 | displaced->step_copy = copy; |
| 1828 | |
| 1829 | make_cleanup (displaced_step_clear_cleanup, displaced); |
| 1830 | |
| 1831 | /* Resume execution at the copy. */ |
| 1832 | regcache_write_pc (regcache, copy); |
| 1833 | |
| 1834 | discard_cleanups (ignore_cleanups); |
| 1835 | |
| 1836 | do_cleanups (old_cleanups); |
| 1837 | |
| 1838 | if (debug_displaced) |
| 1839 | fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to %s\n", |
| 1840 | paddress (gdbarch, copy)); |
| 1841 | |
| 1842 | return 1; |
| 1843 | } |
| 1844 | |
| 1845 | /* Wrapper for displaced_step_prepare_throw that disabled further |
| 1846 | attempts at displaced stepping if we get a memory error. */ |
| 1847 | |
| 1848 | static int |
| 1849 | displaced_step_prepare (ptid_t ptid) |
| 1850 | { |
| 1851 | int prepared = -1; |
| 1852 | |
| 1853 | TRY |
| 1854 | { |
| 1855 | prepared = displaced_step_prepare_throw (ptid); |
| 1856 | } |
| 1857 | CATCH (ex, RETURN_MASK_ERROR) |
| 1858 | { |
| 1859 | struct displaced_step_inferior_state *displaced_state; |
| 1860 | |
| 1861 | if (ex.error != MEMORY_ERROR) |
| 1862 | throw_exception (ex); |
| 1863 | |
| 1864 | if (debug_infrun) |
| 1865 | { |
| 1866 | fprintf_unfiltered (gdb_stdlog, |
| 1867 | "infrun: disabling displaced stepping: %s\n", |
| 1868 | ex.message); |
| 1869 | } |
| 1870 | |
| 1871 | /* Be verbose if "set displaced-stepping" is "on", silent if |
| 1872 | "auto". */ |
| 1873 | if (can_use_displaced_stepping == AUTO_BOOLEAN_TRUE) |
| 1874 | { |
| 1875 | warning (_("disabling displaced stepping: %s"), |
| 1876 | ex.message); |
| 1877 | } |
| 1878 | |
| 1879 | /* Disable further displaced stepping attempts. */ |
| 1880 | displaced_state |
| 1881 | = get_displaced_stepping_state (ptid_get_pid (ptid)); |
| 1882 | displaced_state->failed_before = 1; |
| 1883 | } |
| 1884 | END_CATCH |
| 1885 | |
| 1886 | return prepared; |
| 1887 | } |
| 1888 | |
| 1889 | static void |
| 1890 | write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr, |
| 1891 | const gdb_byte *myaddr, int len) |
| 1892 | { |
| 1893 | struct cleanup *ptid_cleanup = save_inferior_ptid (); |
| 1894 | |
| 1895 | inferior_ptid = ptid; |
| 1896 | write_memory (memaddr, myaddr, len); |
| 1897 | do_cleanups (ptid_cleanup); |
| 1898 | } |
| 1899 | |
| 1900 | /* Restore the contents of the copy area for thread PTID. */ |
| 1901 | |
| 1902 | static void |
| 1903 | displaced_step_restore (struct displaced_step_inferior_state *displaced, |
| 1904 | ptid_t ptid) |
| 1905 | { |
| 1906 | ULONGEST len = gdbarch_max_insn_length (displaced->step_gdbarch); |
| 1907 | |
| 1908 | write_memory_ptid (ptid, displaced->step_copy, |
| 1909 | displaced->step_saved_copy, len); |
| 1910 | if (debug_displaced) |
| 1911 | fprintf_unfiltered (gdb_stdlog, "displaced: restored %s %s\n", |
| 1912 | target_pid_to_str (ptid), |
| 1913 | paddress (displaced->step_gdbarch, |
| 1914 | displaced->step_copy)); |
| 1915 | } |
| 1916 | |
| 1917 | /* If we displaced stepped an instruction successfully, adjust |
| 1918 | registers and memory to yield the same effect the instruction would |
| 1919 | have had if we had executed it at its original address, and return |
| 1920 | 1. If the instruction didn't complete, relocate the PC and return |
| 1921 | -1. If the thread wasn't displaced stepping, return 0. */ |
| 1922 | |
| 1923 | static int |
| 1924 | displaced_step_fixup (ptid_t event_ptid, enum gdb_signal signal) |
| 1925 | { |
| 1926 | struct cleanup *old_cleanups; |
| 1927 | struct displaced_step_inferior_state *displaced |
| 1928 | = get_displaced_stepping_state (ptid_get_pid (event_ptid)); |
| 1929 | int ret; |
| 1930 | |
| 1931 | /* Was any thread of this process doing a displaced step? */ |
| 1932 | if (displaced == NULL) |
| 1933 | return 0; |
| 1934 | |
| 1935 | /* Was this event for the pid we displaced? */ |
| 1936 | if (ptid_equal (displaced->step_ptid, null_ptid) |
| 1937 | || ! ptid_equal (displaced->step_ptid, event_ptid)) |
| 1938 | return 0; |
| 1939 | |
| 1940 | old_cleanups = make_cleanup (displaced_step_clear_cleanup, displaced); |
| 1941 | |
| 1942 | displaced_step_restore (displaced, displaced->step_ptid); |
| 1943 | |
| 1944 | /* Fixup may need to read memory/registers. Switch to the thread |
| 1945 | that we're fixing up. Also, target_stopped_by_watchpoint checks |
| 1946 | the current thread. */ |
| 1947 | switch_to_thread (event_ptid); |
| 1948 | |
| 1949 | /* Did the instruction complete successfully? */ |
| 1950 | if (signal == GDB_SIGNAL_TRAP |
| 1951 | && !(target_stopped_by_watchpoint () |
| 1952 | && (gdbarch_have_nonsteppable_watchpoint (displaced->step_gdbarch) |
| 1953 | || target_have_steppable_watchpoint))) |
| 1954 | { |
| 1955 | /* Fix up the resulting state. */ |
| 1956 | gdbarch_displaced_step_fixup (displaced->step_gdbarch, |
| 1957 | displaced->step_closure, |
| 1958 | displaced->step_original, |
| 1959 | displaced->step_copy, |
| 1960 | get_thread_regcache (displaced->step_ptid)); |
| 1961 | ret = 1; |
| 1962 | } |
| 1963 | else |
| 1964 | { |
| 1965 | /* Since the instruction didn't complete, all we can do is |
| 1966 | relocate the PC. */ |
| 1967 | struct regcache *regcache = get_thread_regcache (event_ptid); |
| 1968 | CORE_ADDR pc = regcache_read_pc (regcache); |
| 1969 | |
| 1970 | pc = displaced->step_original + (pc - displaced->step_copy); |
| 1971 | regcache_write_pc (regcache, pc); |
| 1972 | ret = -1; |
| 1973 | } |
| 1974 | |
| 1975 | do_cleanups (old_cleanups); |
| 1976 | |
| 1977 | displaced->step_ptid = null_ptid; |
| 1978 | |
| 1979 | return ret; |
| 1980 | } |
| 1981 | |
| 1982 | /* Data to be passed around while handling an event. This data is |
| 1983 | discarded between events. */ |
| 1984 | struct execution_control_state |
| 1985 | { |
| 1986 | ptid_t ptid; |
| 1987 | /* The thread that got the event, if this was a thread event; NULL |
| 1988 | otherwise. */ |
| 1989 | struct thread_info *event_thread; |
| 1990 | |
| 1991 | struct target_waitstatus ws; |
| 1992 | int stop_func_filled_in; |
| 1993 | CORE_ADDR stop_func_start; |
| 1994 | CORE_ADDR stop_func_end; |
| 1995 | const char *stop_func_name; |
| 1996 | int wait_some_more; |
| 1997 | |
| 1998 | /* True if the event thread hit the single-step breakpoint of |
| 1999 | another thread. Thus the event doesn't cause a stop, the thread |
| 2000 | needs to be single-stepped past the single-step breakpoint before |
| 2001 | we can switch back to the original stepping thread. */ |
| 2002 | int hit_singlestep_breakpoint; |
| 2003 | }; |
| 2004 | |
| 2005 | /* Clear ECS and set it to point at TP. */ |
| 2006 | |
| 2007 | static void |
| 2008 | reset_ecs (struct execution_control_state *ecs, struct thread_info *tp) |
| 2009 | { |
| 2010 | memset (ecs, 0, sizeof (*ecs)); |
| 2011 | ecs->event_thread = tp; |
| 2012 | ecs->ptid = tp->ptid; |
| 2013 | } |
| 2014 | |
| 2015 | static void keep_going_pass_signal (struct execution_control_state *ecs); |
| 2016 | static void prepare_to_wait (struct execution_control_state *ecs); |
| 2017 | static int keep_going_stepped_thread (struct thread_info *tp); |
| 2018 | static int thread_still_needs_step_over (struct thread_info *tp); |
| 2019 | static void stop_all_threads (void); |
| 2020 | |
| 2021 | /* Are there any pending step-over requests? If so, run all we can |
| 2022 | now and return true. Otherwise, return false. */ |
| 2023 | |
| 2024 | static int |
| 2025 | start_step_over (void) |
| 2026 | { |
| 2027 | struct thread_info *tp, *next; |
| 2028 | |
| 2029 | /* Don't start a new step-over if we already have an in-line |
| 2030 | step-over operation ongoing. */ |
| 2031 | if (step_over_info_valid_p ()) |
| 2032 | return 0; |
| 2033 | |
| 2034 | for (tp = step_over_queue_head; tp != NULL; tp = next) |
| 2035 | { |
| 2036 | struct execution_control_state ecss; |
| 2037 | struct execution_control_state *ecs = &ecss; |
| 2038 | enum step_over_what step_what; |
| 2039 | int must_be_in_line; |
| 2040 | |
| 2041 | next = thread_step_over_chain_next (tp); |
| 2042 | |
| 2043 | /* If this inferior already has a displaced step in process, |
| 2044 | don't start a new one. */ |
| 2045 | if (displaced_step_in_progress (ptid_get_pid (tp->ptid))) |
| 2046 | continue; |
| 2047 | |
| 2048 | step_what = thread_still_needs_step_over (tp); |
| 2049 | must_be_in_line = ((step_what & STEP_OVER_WATCHPOINT) |
| 2050 | || ((step_what & STEP_OVER_BREAKPOINT) |
| 2051 | && !use_displaced_stepping (tp))); |
| 2052 | |
| 2053 | /* We currently stop all threads of all processes to step-over |
| 2054 | in-line. If we need to start a new in-line step-over, let |
| 2055 | any pending displaced steps finish first. */ |
| 2056 | if (must_be_in_line && displaced_step_in_progress_any_inferior ()) |
| 2057 | return 0; |
| 2058 | |
| 2059 | thread_step_over_chain_remove (tp); |
| 2060 | |
| 2061 | if (step_over_queue_head == NULL) |
| 2062 | { |
| 2063 | if (debug_infrun) |
| 2064 | fprintf_unfiltered (gdb_stdlog, |
| 2065 | "infrun: step-over queue now empty\n"); |
| 2066 | } |
| 2067 | |
| 2068 | if (tp->control.trap_expected |
| 2069 | || tp->resumed |
| 2070 | || tp->executing) |
| 2071 | { |
| 2072 | internal_error (__FILE__, __LINE__, |
| 2073 | "[%s] has inconsistent state: " |
| 2074 | "trap_expected=%d, resumed=%d, executing=%d\n", |
| 2075 | target_pid_to_str (tp->ptid), |
| 2076 | tp->control.trap_expected, |
| 2077 | tp->resumed, |
| 2078 | tp->executing); |
| 2079 | } |
| 2080 | |
| 2081 | if (debug_infrun) |
| 2082 | fprintf_unfiltered (gdb_stdlog, |
| 2083 | "infrun: resuming [%s] for step-over\n", |
| 2084 | target_pid_to_str (tp->ptid)); |
| 2085 | |
| 2086 | /* keep_going_pass_signal skips the step-over if the breakpoint |
| 2087 | is no longer inserted. In all-stop, we want to keep looking |
| 2088 | for a thread that needs a step-over instead of resuming TP, |
| 2089 | because we wouldn't be able to resume anything else until the |
| 2090 | target stops again. In non-stop, the resume always resumes |
| 2091 | only TP, so it's OK to let the thread resume freely. */ |
| 2092 | if (!target_is_non_stop_p () && !step_what) |
| 2093 | continue; |
| 2094 | |
| 2095 | switch_to_thread (tp->ptid); |
| 2096 | reset_ecs (ecs, tp); |
| 2097 | keep_going_pass_signal (ecs); |
| 2098 | |
| 2099 | if (!ecs->wait_some_more) |
| 2100 | error (_("Command aborted.")); |
| 2101 | |
| 2102 | gdb_assert (tp->resumed); |
| 2103 | |
| 2104 | /* If we started a new in-line step-over, we're done. */ |
| 2105 | if (step_over_info_valid_p ()) |
| 2106 | { |
| 2107 | gdb_assert (tp->control.trap_expected); |
| 2108 | return 1; |
| 2109 | } |
| 2110 | |
| 2111 | if (!target_is_non_stop_p ()) |
| 2112 | { |
| 2113 | /* On all-stop, shouldn't have resumed unless we needed a |
| 2114 | step over. */ |
| 2115 | gdb_assert (tp->control.trap_expected |
| 2116 | || tp->step_after_step_resume_breakpoint); |
| 2117 | |
| 2118 | /* With remote targets (at least), in all-stop, we can't |
| 2119 | issue any further remote commands until the program stops |
| 2120 | again. */ |
| 2121 | return 1; |
| 2122 | } |
| 2123 | |
| 2124 | /* Either the thread no longer needed a step-over, or a new |
| 2125 | displaced stepping sequence started. Even in the latter |
| 2126 | case, continue looking. Maybe we can also start another |
| 2127 | displaced step on a thread of other process. */ |
| 2128 | } |
| 2129 | |
| 2130 | return 0; |
| 2131 | } |
| 2132 | |
| 2133 | /* Update global variables holding ptids to hold NEW_PTID if they were |
| 2134 | holding OLD_PTID. */ |
| 2135 | static void |
| 2136 | infrun_thread_ptid_changed (ptid_t old_ptid, ptid_t new_ptid) |
| 2137 | { |
| 2138 | struct displaced_step_request *it; |
| 2139 | struct displaced_step_inferior_state *displaced; |
| 2140 | |
| 2141 | if (ptid_equal (inferior_ptid, old_ptid)) |
| 2142 | inferior_ptid = new_ptid; |
| 2143 | |
| 2144 | for (displaced = displaced_step_inferior_states; |
| 2145 | displaced; |
| 2146 | displaced = displaced->next) |
| 2147 | { |
| 2148 | if (ptid_equal (displaced->step_ptid, old_ptid)) |
| 2149 | displaced->step_ptid = new_ptid; |
| 2150 | } |
| 2151 | } |
| 2152 | |
| 2153 | \f |
| 2154 | /* Resuming. */ |
| 2155 | |
| 2156 | /* Things to clean up if we QUIT out of resume (). */ |
| 2157 | static void |
| 2158 | resume_cleanups (void *ignore) |
| 2159 | { |
| 2160 | if (!ptid_equal (inferior_ptid, null_ptid)) |
| 2161 | delete_single_step_breakpoints (inferior_thread ()); |
| 2162 | |
| 2163 | normal_stop (); |
| 2164 | } |
| 2165 | |
| 2166 | static const char schedlock_off[] = "off"; |
| 2167 | static const char schedlock_on[] = "on"; |
| 2168 | static const char schedlock_step[] = "step"; |
| 2169 | static const char *const scheduler_enums[] = { |
| 2170 | schedlock_off, |
| 2171 | schedlock_on, |
| 2172 | schedlock_step, |
| 2173 | NULL |
| 2174 | }; |
| 2175 | static const char *scheduler_mode = schedlock_off; |
| 2176 | static void |
| 2177 | show_scheduler_mode (struct ui_file *file, int from_tty, |
| 2178 | struct cmd_list_element *c, const char *value) |
| 2179 | { |
| 2180 | fprintf_filtered (file, |
| 2181 | _("Mode for locking scheduler " |
| 2182 | "during execution is \"%s\".\n"), |
| 2183 | value); |
| 2184 | } |
| 2185 | |
| 2186 | static void |
| 2187 | set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c) |
| 2188 | { |
| 2189 | if (!target_can_lock_scheduler) |
| 2190 | { |
| 2191 | scheduler_mode = schedlock_off; |
| 2192 | error (_("Target '%s' cannot support this command."), target_shortname); |
| 2193 | } |
| 2194 | } |
| 2195 | |
| 2196 | /* True if execution commands resume all threads of all processes by |
| 2197 | default; otherwise, resume only threads of the current inferior |
| 2198 | process. */ |
| 2199 | int sched_multi = 0; |
| 2200 | |
| 2201 | /* Try to setup for software single stepping over the specified location. |
| 2202 | Return 1 if target_resume() should use hardware single step. |
| 2203 | |
| 2204 | GDBARCH the current gdbarch. |
| 2205 | PC the location to step over. */ |
| 2206 | |
| 2207 | static int |
| 2208 | maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 2209 | { |
| 2210 | int hw_step = 1; |
| 2211 | |
| 2212 | if (execution_direction == EXEC_FORWARD |
| 2213 | && gdbarch_software_single_step_p (gdbarch) |
| 2214 | && gdbarch_software_single_step (gdbarch, get_current_frame ())) |
| 2215 | { |
| 2216 | hw_step = 0; |
| 2217 | } |
| 2218 | return hw_step; |
| 2219 | } |
| 2220 | |
| 2221 | /* See infrun.h. */ |
| 2222 | |
| 2223 | ptid_t |
| 2224 | user_visible_resume_ptid (int step) |
| 2225 | { |
| 2226 | ptid_t resume_ptid; |
| 2227 | |
| 2228 | if (non_stop) |
| 2229 | { |
| 2230 | /* With non-stop mode on, threads are always handled |
| 2231 | individually. */ |
| 2232 | resume_ptid = inferior_ptid; |
| 2233 | } |
| 2234 | else if ((scheduler_mode == schedlock_on) |
| 2235 | || (scheduler_mode == schedlock_step && step)) |
| 2236 | { |
| 2237 | /* User-settable 'scheduler' mode requires solo thread |
| 2238 | resume. */ |
| 2239 | resume_ptid = inferior_ptid; |
| 2240 | } |
| 2241 | else if (!sched_multi && target_supports_multi_process ()) |
| 2242 | { |
| 2243 | /* Resume all threads of the current process (and none of other |
| 2244 | processes). */ |
| 2245 | resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid)); |
| 2246 | } |
| 2247 | else |
| 2248 | { |
| 2249 | /* Resume all threads of all processes. */ |
| 2250 | resume_ptid = RESUME_ALL; |
| 2251 | } |
| 2252 | |
| 2253 | return resume_ptid; |
| 2254 | } |
| 2255 | |
| 2256 | /* Return a ptid representing the set of threads that we will resume, |
| 2257 | in the perspective of the target, assuming run control handling |
| 2258 | does not require leaving some threads stopped (e.g., stepping past |
| 2259 | breakpoint). USER_STEP indicates whether we're about to start the |
| 2260 | target for a stepping command. */ |
| 2261 | |
| 2262 | static ptid_t |
| 2263 | internal_resume_ptid (int user_step) |
| 2264 | { |
| 2265 | /* In non-stop, we always control threads individually. Note that |
| 2266 | the target may always work in non-stop mode even with "set |
| 2267 | non-stop off", in which case user_visible_resume_ptid could |
| 2268 | return a wildcard ptid. */ |
| 2269 | if (target_is_non_stop_p ()) |
| 2270 | return inferior_ptid; |
| 2271 | else |
| 2272 | return user_visible_resume_ptid (user_step); |
| 2273 | } |
| 2274 | |
| 2275 | /* Wrapper for target_resume, that handles infrun-specific |
| 2276 | bookkeeping. */ |
| 2277 | |
| 2278 | static void |
| 2279 | do_target_resume (ptid_t resume_ptid, int step, enum gdb_signal sig) |
| 2280 | { |
| 2281 | struct thread_info *tp = inferior_thread (); |
| 2282 | |
| 2283 | /* Install inferior's terminal modes. */ |
| 2284 | target_terminal_inferior (); |
| 2285 | |
| 2286 | /* Avoid confusing the next resume, if the next stop/resume |
| 2287 | happens to apply to another thread. */ |
| 2288 | tp->suspend.stop_signal = GDB_SIGNAL_0; |
| 2289 | |
| 2290 | /* Advise target which signals may be handled silently. |
| 2291 | |
| 2292 | If we have removed breakpoints because we are stepping over one |
| 2293 | in-line (in any thread), we need to receive all signals to avoid |
| 2294 | accidentally skipping a breakpoint during execution of a signal |
| 2295 | handler. |
| 2296 | |
| 2297 | Likewise if we're displaced stepping, otherwise a trap for a |
| 2298 | breakpoint in a signal handler might be confused with the |
| 2299 | displaced step finishing. We don't make the displaced_step_fixup |
| 2300 | step distinguish the cases instead, because: |
| 2301 | |
| 2302 | - a backtrace while stopped in the signal handler would show the |
| 2303 | scratch pad as frame older than the signal handler, instead of |
| 2304 | the real mainline code. |
| 2305 | |
| 2306 | - when the thread is later resumed, the signal handler would |
| 2307 | return to the scratch pad area, which would no longer be |
| 2308 | valid. */ |
| 2309 | if (step_over_info_valid_p () |
| 2310 | || displaced_step_in_progress (ptid_get_pid (tp->ptid))) |
| 2311 | target_pass_signals (0, NULL); |
| 2312 | else |
| 2313 | target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass); |
| 2314 | |
| 2315 | target_resume (resume_ptid, step, sig); |
| 2316 | } |
| 2317 | |
| 2318 | /* Resume the inferior, but allow a QUIT. This is useful if the user |
| 2319 | wants to interrupt some lengthy single-stepping operation |
| 2320 | (for child processes, the SIGINT goes to the inferior, and so |
| 2321 | we get a SIGINT random_signal, but for remote debugging and perhaps |
| 2322 | other targets, that's not true). |
| 2323 | |
| 2324 | SIG is the signal to give the inferior (zero for none). */ |
| 2325 | void |
| 2326 | resume (enum gdb_signal sig) |
| 2327 | { |
| 2328 | struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0); |
| 2329 | struct regcache *regcache = get_current_regcache (); |
| 2330 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 2331 | struct thread_info *tp = inferior_thread (); |
| 2332 | CORE_ADDR pc = regcache_read_pc (regcache); |
| 2333 | struct address_space *aspace = get_regcache_aspace (regcache); |
| 2334 | ptid_t resume_ptid; |
| 2335 | /* This represents the user's step vs continue request. When |
| 2336 | deciding whether "set scheduler-locking step" applies, it's the |
| 2337 | user's intention that counts. */ |
| 2338 | const int user_step = tp->control.stepping_command; |
| 2339 | /* This represents what we'll actually request the target to do. |
| 2340 | This can decay from a step to a continue, if e.g., we need to |
| 2341 | implement single-stepping with breakpoints (software |
| 2342 | single-step). */ |
| 2343 | int step; |
| 2344 | |
| 2345 | gdb_assert (!thread_is_in_step_over_chain (tp)); |
| 2346 | |
| 2347 | QUIT; |
| 2348 | |
| 2349 | if (tp->suspend.waitstatus_pending_p) |
| 2350 | { |
| 2351 | if (debug_infrun) |
| 2352 | { |
| 2353 | char *statstr; |
| 2354 | |
| 2355 | statstr = target_waitstatus_to_string (&tp->suspend.waitstatus); |
| 2356 | fprintf_unfiltered (gdb_stdlog, |
| 2357 | "infrun: resume: thread %s has pending wait status %s " |
| 2358 | "(currently_stepping=%d).\n", |
| 2359 | target_pid_to_str (tp->ptid), statstr, |
| 2360 | currently_stepping (tp)); |
| 2361 | xfree (statstr); |
| 2362 | } |
| 2363 | |
| 2364 | tp->resumed = 1; |
| 2365 | |
| 2366 | /* FIXME: What should we do if we are supposed to resume this |
| 2367 | thread with a signal? Maybe we should maintain a queue of |
| 2368 | pending signals to deliver. */ |
| 2369 | if (sig != GDB_SIGNAL_0) |
| 2370 | { |
| 2371 | warning (_("Couldn't deliver signal %s to %s."), |
| 2372 | gdb_signal_to_name (sig), target_pid_to_str (tp->ptid)); |
| 2373 | } |
| 2374 | |
| 2375 | tp->suspend.stop_signal = GDB_SIGNAL_0; |
| 2376 | discard_cleanups (old_cleanups); |
| 2377 | |
| 2378 | if (target_can_async_p ()) |
| 2379 | target_async (1); |
| 2380 | return; |
| 2381 | } |
| 2382 | |
| 2383 | tp->stepped_breakpoint = 0; |
| 2384 | |
| 2385 | /* Depends on stepped_breakpoint. */ |
| 2386 | step = currently_stepping (tp); |
| 2387 | |
| 2388 | if (current_inferior ()->waiting_for_vfork_done) |
| 2389 | { |
| 2390 | /* Don't try to single-step a vfork parent that is waiting for |
| 2391 | the child to get out of the shared memory region (by exec'ing |
| 2392 | or exiting). This is particularly important on software |
| 2393 | single-step archs, as the child process would trip on the |
| 2394 | software single step breakpoint inserted for the parent |
| 2395 | process. Since the parent will not actually execute any |
| 2396 | instruction until the child is out of the shared region (such |
| 2397 | are vfork's semantics), it is safe to simply continue it. |
| 2398 | Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for |
| 2399 | the parent, and tell it to `keep_going', which automatically |
| 2400 | re-sets it stepping. */ |
| 2401 | if (debug_infrun) |
| 2402 | fprintf_unfiltered (gdb_stdlog, |
| 2403 | "infrun: resume : clear step\n"); |
| 2404 | step = 0; |
| 2405 | } |
| 2406 | |
| 2407 | if (debug_infrun) |
| 2408 | fprintf_unfiltered (gdb_stdlog, |
| 2409 | "infrun: resume (step=%d, signal=%s), " |
| 2410 | "trap_expected=%d, current thread [%s] at %s\n", |
| 2411 | step, gdb_signal_to_symbol_string (sig), |
| 2412 | tp->control.trap_expected, |
| 2413 | target_pid_to_str (inferior_ptid), |
| 2414 | paddress (gdbarch, pc)); |
| 2415 | |
| 2416 | /* Normally, by the time we reach `resume', the breakpoints are either |
| 2417 | removed or inserted, as appropriate. The exception is if we're sitting |
| 2418 | at a permanent breakpoint; we need to step over it, but permanent |
| 2419 | breakpoints can't be removed. So we have to test for it here. */ |
| 2420 | if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here) |
| 2421 | { |
| 2422 | if (sig != GDB_SIGNAL_0) |
| 2423 | { |
| 2424 | /* We have a signal to pass to the inferior. The resume |
| 2425 | may, or may not take us to the signal handler. If this |
| 2426 | is a step, we'll need to stop in the signal handler, if |
| 2427 | there's one, (if the target supports stepping into |
| 2428 | handlers), or in the next mainline instruction, if |
| 2429 | there's no handler. If this is a continue, we need to be |
| 2430 | sure to run the handler with all breakpoints inserted. |
| 2431 | In all cases, set a breakpoint at the current address |
| 2432 | (where the handler returns to), and once that breakpoint |
| 2433 | is hit, resume skipping the permanent breakpoint. If |
| 2434 | that breakpoint isn't hit, then we've stepped into the |
| 2435 | signal handler (or hit some other event). We'll delete |
| 2436 | the step-resume breakpoint then. */ |
| 2437 | |
| 2438 | if (debug_infrun) |
| 2439 | fprintf_unfiltered (gdb_stdlog, |
| 2440 | "infrun: resume: skipping permanent breakpoint, " |
| 2441 | "deliver signal first\n"); |
| 2442 | |
| 2443 | clear_step_over_info (); |
| 2444 | tp->control.trap_expected = 0; |
| 2445 | |
| 2446 | if (tp->control.step_resume_breakpoint == NULL) |
| 2447 | { |
| 2448 | /* Set a "high-priority" step-resume, as we don't want |
| 2449 | user breakpoints at PC to trigger (again) when this |
| 2450 | hits. */ |
| 2451 | insert_hp_step_resume_breakpoint_at_frame (get_current_frame ()); |
| 2452 | gdb_assert (tp->control.step_resume_breakpoint->loc->permanent); |
| 2453 | |
| 2454 | tp->step_after_step_resume_breakpoint = step; |
| 2455 | } |
| 2456 | |
| 2457 | insert_breakpoints (); |
| 2458 | } |
| 2459 | else |
| 2460 | { |
| 2461 | /* There's no signal to pass, we can go ahead and skip the |
| 2462 | permanent breakpoint manually. */ |
| 2463 | if (debug_infrun) |
| 2464 | fprintf_unfiltered (gdb_stdlog, |
| 2465 | "infrun: resume: skipping permanent breakpoint\n"); |
| 2466 | gdbarch_skip_permanent_breakpoint (gdbarch, regcache); |
| 2467 | /* Update pc to reflect the new address from which we will |
| 2468 | execute instructions. */ |
| 2469 | pc = regcache_read_pc (regcache); |
| 2470 | |
| 2471 | if (step) |
| 2472 | { |
| 2473 | /* We've already advanced the PC, so the stepping part |
| 2474 | is done. Now we need to arrange for a trap to be |
| 2475 | reported to handle_inferior_event. Set a breakpoint |
| 2476 | at the current PC, and run to it. Don't update |
| 2477 | prev_pc, because if we end in |
| 2478 | switch_back_to_stepped_thread, we want the "expected |
| 2479 | thread advanced also" branch to be taken. IOW, we |
| 2480 | don't want this thread to step further from PC |
| 2481 | (overstep). */ |
| 2482 | gdb_assert (!step_over_info_valid_p ()); |
| 2483 | insert_single_step_breakpoint (gdbarch, aspace, pc); |
| 2484 | insert_breakpoints (); |
| 2485 | |
| 2486 | resume_ptid = internal_resume_ptid (user_step); |
| 2487 | do_target_resume (resume_ptid, 0, GDB_SIGNAL_0); |
| 2488 | discard_cleanups (old_cleanups); |
| 2489 | tp->resumed = 1; |
| 2490 | return; |
| 2491 | } |
| 2492 | } |
| 2493 | } |
| 2494 | |
| 2495 | /* If we have a breakpoint to step over, make sure to do a single |
| 2496 | step only. Same if we have software watchpoints. */ |
| 2497 | if (tp->control.trap_expected || bpstat_should_step ()) |
| 2498 | tp->control.may_range_step = 0; |
| 2499 | |
| 2500 | /* If enabled, step over breakpoints by executing a copy of the |
| 2501 | instruction at a different address. |
| 2502 | |
| 2503 | We can't use displaced stepping when we have a signal to deliver; |
| 2504 | the comments for displaced_step_prepare explain why. The |
| 2505 | comments in the handle_inferior event for dealing with 'random |
| 2506 | signals' explain what we do instead. |
| 2507 | |
| 2508 | We can't use displaced stepping when we are waiting for vfork_done |
| 2509 | event, displaced stepping breaks the vfork child similarly as single |
| 2510 | step software breakpoint. */ |
| 2511 | if (tp->control.trap_expected |
| 2512 | && use_displaced_stepping (tp) |
| 2513 | && !step_over_info_valid_p () |
| 2514 | && sig == GDB_SIGNAL_0 |
| 2515 | && !current_inferior ()->waiting_for_vfork_done) |
| 2516 | { |
| 2517 | int prepared = displaced_step_prepare (inferior_ptid); |
| 2518 | |
| 2519 | if (prepared == 0) |
| 2520 | { |
| 2521 | if (debug_infrun) |
| 2522 | fprintf_unfiltered (gdb_stdlog, |
| 2523 | "Got placed in step-over queue\n"); |
| 2524 | |
| 2525 | tp->control.trap_expected = 0; |
| 2526 | discard_cleanups (old_cleanups); |
| 2527 | return; |
| 2528 | } |
| 2529 | else if (prepared < 0) |
| 2530 | { |
| 2531 | /* Fallback to stepping over the breakpoint in-line. */ |
| 2532 | |
| 2533 | if (target_is_non_stop_p ()) |
| 2534 | stop_all_threads (); |
| 2535 | |
| 2536 | set_step_over_info (get_regcache_aspace (regcache), |
| 2537 | regcache_read_pc (regcache), 0); |
| 2538 | |
| 2539 | step = maybe_software_singlestep (gdbarch, pc); |
| 2540 | |
| 2541 | insert_breakpoints (); |
| 2542 | } |
| 2543 | else if (prepared > 0) |
| 2544 | { |
| 2545 | struct displaced_step_inferior_state *displaced; |
| 2546 | |
| 2547 | /* Update pc to reflect the new address from which we will |
| 2548 | execute instructions due to displaced stepping. */ |
| 2549 | pc = regcache_read_pc (get_thread_regcache (inferior_ptid)); |
| 2550 | |
| 2551 | displaced = get_displaced_stepping_state (ptid_get_pid (inferior_ptid)); |
| 2552 | step = gdbarch_displaced_step_hw_singlestep (gdbarch, |
| 2553 | displaced->step_closure); |
| 2554 | } |
| 2555 | } |
| 2556 | |
| 2557 | /* Do we need to do it the hard way, w/temp breakpoints? */ |
| 2558 | else if (step) |
| 2559 | step = maybe_software_singlestep (gdbarch, pc); |
| 2560 | |
| 2561 | /* Currently, our software single-step implementation leads to different |
| 2562 | results than hardware single-stepping in one situation: when stepping |
| 2563 | into delivering a signal which has an associated signal handler, |
| 2564 | hardware single-step will stop at the first instruction of the handler, |
| 2565 | while software single-step will simply skip execution of the handler. |
| 2566 | |
| 2567 | For now, this difference in behavior is accepted since there is no |
| 2568 | easy way to actually implement single-stepping into a signal handler |
| 2569 | without kernel support. |
| 2570 | |
| 2571 | However, there is one scenario where this difference leads to follow-on |
| 2572 | problems: if we're stepping off a breakpoint by removing all breakpoints |
| 2573 | and then single-stepping. In this case, the software single-step |
| 2574 | behavior means that even if there is a *breakpoint* in the signal |
| 2575 | handler, GDB still would not stop. |
| 2576 | |
| 2577 | Fortunately, we can at least fix this particular issue. We detect |
| 2578 | here the case where we are about to deliver a signal while software |
| 2579 | single-stepping with breakpoints removed. In this situation, we |
| 2580 | revert the decisions to remove all breakpoints and insert single- |
| 2581 | step breakpoints, and instead we install a step-resume breakpoint |
| 2582 | at the current address, deliver the signal without stepping, and |
| 2583 | once we arrive back at the step-resume breakpoint, actually step |
| 2584 | over the breakpoint we originally wanted to step over. */ |
| 2585 | if (thread_has_single_step_breakpoints_set (tp) |
| 2586 | && sig != GDB_SIGNAL_0 |
| 2587 | && step_over_info_valid_p ()) |
| 2588 | { |
| 2589 | /* If we have nested signals or a pending signal is delivered |
| 2590 | immediately after a handler returns, might might already have |
| 2591 | a step-resume breakpoint set on the earlier handler. We cannot |
| 2592 | set another step-resume breakpoint; just continue on until the |
| 2593 | original breakpoint is hit. */ |
| 2594 | if (tp->control.step_resume_breakpoint == NULL) |
| 2595 | { |
| 2596 | insert_hp_step_resume_breakpoint_at_frame (get_current_frame ()); |
| 2597 | tp->step_after_step_resume_breakpoint = 1; |
| 2598 | } |
| 2599 | |
| 2600 | delete_single_step_breakpoints (tp); |
| 2601 | |
| 2602 | clear_step_over_info (); |
| 2603 | tp->control.trap_expected = 0; |
| 2604 | |
| 2605 | insert_breakpoints (); |
| 2606 | } |
| 2607 | |
| 2608 | /* If STEP is set, it's a request to use hardware stepping |
| 2609 | facilities. But in that case, we should never |
| 2610 | use singlestep breakpoint. */ |
| 2611 | gdb_assert (!(thread_has_single_step_breakpoints_set (tp) && step)); |
| 2612 | |
| 2613 | /* Decide the set of threads to ask the target to resume. */ |
| 2614 | if ((step || thread_has_single_step_breakpoints_set (tp)) |
| 2615 | && tp->control.trap_expected) |
| 2616 | { |
| 2617 | /* We're allowing a thread to run past a breakpoint it has |
| 2618 | hit, by single-stepping the thread with the breakpoint |
| 2619 | removed. In which case, we need to single-step only this |
| 2620 | thread, and keep others stopped, as they can miss this |
| 2621 | breakpoint if allowed to run. */ |
| 2622 | resume_ptid = inferior_ptid; |
| 2623 | } |
| 2624 | else |
| 2625 | resume_ptid = internal_resume_ptid (user_step); |
| 2626 | |
| 2627 | if (execution_direction != EXEC_REVERSE |
| 2628 | && step && breakpoint_inserted_here_p (aspace, pc)) |
| 2629 | { |
| 2630 | /* There are two cases where we currently need to step a |
| 2631 | breakpoint instruction when we have a signal to deliver: |
| 2632 | |
| 2633 | - See handle_signal_stop where we handle random signals that |
| 2634 | could take out us out of the stepping range. Normally, in |
| 2635 | that case we end up continuing (instead of stepping) over the |
| 2636 | signal handler with a breakpoint at PC, but there are cases |
| 2637 | where we should _always_ single-step, even if we have a |
| 2638 | step-resume breakpoint, like when a software watchpoint is |
| 2639 | set. Assuming single-stepping and delivering a signal at the |
| 2640 | same time would takes us to the signal handler, then we could |
| 2641 | have removed the breakpoint at PC to step over it. However, |
| 2642 | some hardware step targets (like e.g., Mac OS) can't step |
| 2643 | into signal handlers, and for those, we need to leave the |
| 2644 | breakpoint at PC inserted, as otherwise if the handler |
| 2645 | recurses and executes PC again, it'll miss the breakpoint. |
| 2646 | So we leave the breakpoint inserted anyway, but we need to |
| 2647 | record that we tried to step a breakpoint instruction, so |
| 2648 | that adjust_pc_after_break doesn't end up confused. |
| 2649 | |
| 2650 | - In non-stop if we insert a breakpoint (e.g., a step-resume) |
| 2651 | in one thread after another thread that was stepping had been |
| 2652 | momentarily paused for a step-over. When we re-resume the |
| 2653 | stepping thread, it may be resumed from that address with a |
| 2654 | breakpoint that hasn't trapped yet. Seen with |
| 2655 | gdb.threads/non-stop-fair-events.exp, on targets that don't |
| 2656 | do displaced stepping. */ |
| 2657 | |
| 2658 | if (debug_infrun) |
| 2659 | fprintf_unfiltered (gdb_stdlog, |
| 2660 | "infrun: resume: [%s] stepped breakpoint\n", |
| 2661 | target_pid_to_str (tp->ptid)); |
| 2662 | |
| 2663 | tp->stepped_breakpoint = 1; |
| 2664 | |
| 2665 | /* Most targets can step a breakpoint instruction, thus |
| 2666 | executing it normally. But if this one cannot, just |
| 2667 | continue and we will hit it anyway. */ |
| 2668 | if (gdbarch_cannot_step_breakpoint (gdbarch)) |
| 2669 | step = 0; |
| 2670 | } |
| 2671 | |
| 2672 | if (debug_displaced |
| 2673 | && tp->control.trap_expected |
| 2674 | && use_displaced_stepping (tp) |
| 2675 | && !step_over_info_valid_p ()) |
| 2676 | { |
| 2677 | struct regcache *resume_regcache = get_thread_regcache (tp->ptid); |
| 2678 | struct gdbarch *resume_gdbarch = get_regcache_arch (resume_regcache); |
| 2679 | CORE_ADDR actual_pc = regcache_read_pc (resume_regcache); |
| 2680 | gdb_byte buf[4]; |
| 2681 | |
| 2682 | fprintf_unfiltered (gdb_stdlog, "displaced: run %s: ", |
| 2683 | paddress (resume_gdbarch, actual_pc)); |
| 2684 | read_memory (actual_pc, buf, sizeof (buf)); |
| 2685 | displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf)); |
| 2686 | } |
| 2687 | |
| 2688 | if (tp->control.may_range_step) |
| 2689 | { |
| 2690 | /* If we're resuming a thread with the PC out of the step |
| 2691 | range, then we're doing some nested/finer run control |
| 2692 | operation, like stepping the thread out of the dynamic |
| 2693 | linker or the displaced stepping scratch pad. We |
| 2694 | shouldn't have allowed a range step then. */ |
| 2695 | gdb_assert (pc_in_thread_step_range (pc, tp)); |
| 2696 | } |
| 2697 | |
| 2698 | do_target_resume (resume_ptid, step, sig); |
| 2699 | tp->resumed = 1; |
| 2700 | discard_cleanups (old_cleanups); |
| 2701 | } |
| 2702 | \f |
| 2703 | /* Proceeding. */ |
| 2704 | |
| 2705 | /* See infrun.h. */ |
| 2706 | |
| 2707 | /* Counter that tracks number of user visible stops. This can be used |
| 2708 | to tell whether a command has proceeded the inferior past the |
| 2709 | current location. This allows e.g., inferior function calls in |
| 2710 | breakpoint commands to not interrupt the command list. When the |
| 2711 | call finishes successfully, the inferior is standing at the same |
| 2712 | breakpoint as if nothing happened (and so we don't call |
| 2713 | normal_stop). */ |
| 2714 | static ULONGEST current_stop_id; |
| 2715 | |
| 2716 | /* See infrun.h. */ |
| 2717 | |
| 2718 | ULONGEST |
| 2719 | get_stop_id (void) |
| 2720 | { |
| 2721 | return current_stop_id; |
| 2722 | } |
| 2723 | |
| 2724 | /* Called when we report a user visible stop. */ |
| 2725 | |
| 2726 | static void |
| 2727 | new_stop_id (void) |
| 2728 | { |
| 2729 | current_stop_id++; |
| 2730 | } |
| 2731 | |
| 2732 | /* Clear out all variables saying what to do when inferior is continued. |
| 2733 | First do this, then set the ones you want, then call `proceed'. */ |
| 2734 | |
| 2735 | static void |
| 2736 | clear_proceed_status_thread (struct thread_info *tp) |
| 2737 | { |
| 2738 | if (debug_infrun) |
| 2739 | fprintf_unfiltered (gdb_stdlog, |
| 2740 | "infrun: clear_proceed_status_thread (%s)\n", |
| 2741 | target_pid_to_str (tp->ptid)); |
| 2742 | |
| 2743 | /* If we're starting a new sequence, then the previous finished |
| 2744 | single-step is no longer relevant. */ |
| 2745 | if (tp->suspend.waitstatus_pending_p) |
| 2746 | { |
| 2747 | if (tp->suspend.stop_reason == TARGET_STOPPED_BY_SINGLE_STEP) |
| 2748 | { |
| 2749 | if (debug_infrun) |
| 2750 | fprintf_unfiltered (gdb_stdlog, |
| 2751 | "infrun: clear_proceed_status: pending " |
| 2752 | "event of %s was a finished step. " |
| 2753 | "Discarding.\n", |
| 2754 | target_pid_to_str (tp->ptid)); |
| 2755 | |
| 2756 | tp->suspend.waitstatus_pending_p = 0; |
| 2757 | tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON; |
| 2758 | } |
| 2759 | else if (debug_infrun) |
| 2760 | { |
| 2761 | char *statstr; |
| 2762 | |
| 2763 | statstr = target_waitstatus_to_string (&tp->suspend.waitstatus); |
| 2764 | fprintf_unfiltered (gdb_stdlog, |
| 2765 | "infrun: clear_proceed_status_thread: thread %s " |
| 2766 | "has pending wait status %s " |
| 2767 | "(currently_stepping=%d).\n", |
| 2768 | target_pid_to_str (tp->ptid), statstr, |
| 2769 | currently_stepping (tp)); |
| 2770 | xfree (statstr); |
| 2771 | } |
| 2772 | } |
| 2773 | |
| 2774 | /* If this signal should not be seen by program, give it zero. |
| 2775 | Used for debugging signals. */ |
| 2776 | if (!signal_pass_state (tp->suspend.stop_signal)) |
| 2777 | tp->suspend.stop_signal = GDB_SIGNAL_0; |
| 2778 | |
| 2779 | thread_fsm_delete (tp->thread_fsm); |
| 2780 | tp->thread_fsm = NULL; |
| 2781 | |
| 2782 | tp->control.trap_expected = 0; |
| 2783 | tp->control.step_range_start = 0; |
| 2784 | tp->control.step_range_end = 0; |
| 2785 | tp->control.may_range_step = 0; |
| 2786 | tp->control.step_frame_id = null_frame_id; |
| 2787 | tp->control.step_stack_frame_id = null_frame_id; |
| 2788 | tp->control.step_over_calls = STEP_OVER_UNDEBUGGABLE; |
| 2789 | tp->control.step_start_function = NULL; |
| 2790 | tp->stop_requested = 0; |
| 2791 | |
| 2792 | tp->control.stop_step = 0; |
| 2793 | |
| 2794 | tp->control.proceed_to_finish = 0; |
| 2795 | |
| 2796 | tp->control.command_interp = NULL; |
| 2797 | tp->control.stepping_command = 0; |
| 2798 | |
| 2799 | /* Discard any remaining commands or status from previous stop. */ |
| 2800 | bpstat_clear (&tp->control.stop_bpstat); |
| 2801 | } |
| 2802 | |
| 2803 | void |
| 2804 | clear_proceed_status (int step) |
| 2805 | { |
| 2806 | if (!non_stop) |
| 2807 | { |
| 2808 | struct thread_info *tp; |
| 2809 | ptid_t resume_ptid; |
| 2810 | |
| 2811 | resume_ptid = user_visible_resume_ptid (step); |
| 2812 | |
| 2813 | /* In all-stop mode, delete the per-thread status of all threads |
| 2814 | we're about to resume, implicitly and explicitly. */ |
| 2815 | ALL_NON_EXITED_THREADS (tp) |
| 2816 | { |
| 2817 | if (!ptid_match (tp->ptid, resume_ptid)) |
| 2818 | continue; |
| 2819 | clear_proceed_status_thread (tp); |
| 2820 | } |
| 2821 | } |
| 2822 | |
| 2823 | if (!ptid_equal (inferior_ptid, null_ptid)) |
| 2824 | { |
| 2825 | struct inferior *inferior; |
| 2826 | |
| 2827 | if (non_stop) |
| 2828 | { |
| 2829 | /* If in non-stop mode, only delete the per-thread status of |
| 2830 | the current thread. */ |
| 2831 | clear_proceed_status_thread (inferior_thread ()); |
| 2832 | } |
| 2833 | |
| 2834 | inferior = current_inferior (); |
| 2835 | inferior->control.stop_soon = NO_STOP_QUIETLY; |
| 2836 | } |
| 2837 | |
| 2838 | stop_after_trap = 0; |
| 2839 | |
| 2840 | observer_notify_about_to_proceed (); |
| 2841 | } |
| 2842 | |
| 2843 | /* Returns true if TP is still stopped at a breakpoint that needs |
| 2844 | stepping-over in order to make progress. If the breakpoint is gone |
| 2845 | meanwhile, we can skip the whole step-over dance. */ |
| 2846 | |
| 2847 | static int |
| 2848 | thread_still_needs_step_over_bp (struct thread_info *tp) |
| 2849 | { |
| 2850 | if (tp->stepping_over_breakpoint) |
| 2851 | { |
| 2852 | struct regcache *regcache = get_thread_regcache (tp->ptid); |
| 2853 | |
| 2854 | if (breakpoint_here_p (get_regcache_aspace (regcache), |
| 2855 | regcache_read_pc (regcache)) |
| 2856 | == ordinary_breakpoint_here) |
| 2857 | return 1; |
| 2858 | |
| 2859 | tp->stepping_over_breakpoint = 0; |
| 2860 | } |
| 2861 | |
| 2862 | return 0; |
| 2863 | } |
| 2864 | |
| 2865 | /* Check whether thread TP still needs to start a step-over in order |
| 2866 | to make progress when resumed. Returns an bitwise or of enum |
| 2867 | step_over_what bits, indicating what needs to be stepped over. */ |
| 2868 | |
| 2869 | static int |
| 2870 | thread_still_needs_step_over (struct thread_info *tp) |
| 2871 | { |
| 2872 | struct inferior *inf = find_inferior_ptid (tp->ptid); |
| 2873 | int what = 0; |
| 2874 | |
| 2875 | if (thread_still_needs_step_over_bp (tp)) |
| 2876 | what |= STEP_OVER_BREAKPOINT; |
| 2877 | |
| 2878 | if (tp->stepping_over_watchpoint |
| 2879 | && !target_have_steppable_watchpoint) |
| 2880 | what |= STEP_OVER_WATCHPOINT; |
| 2881 | |
| 2882 | return what; |
| 2883 | } |
| 2884 | |
| 2885 | /* Returns true if scheduler locking applies. STEP indicates whether |
| 2886 | we're about to do a step/next-like command to a thread. */ |
| 2887 | |
| 2888 | static int |
| 2889 | schedlock_applies (struct thread_info *tp) |
| 2890 | { |
| 2891 | return (scheduler_mode == schedlock_on |
| 2892 | || (scheduler_mode == schedlock_step |
| 2893 | && tp->control.stepping_command)); |
| 2894 | } |
| 2895 | |
| 2896 | /* Basic routine for continuing the program in various fashions. |
| 2897 | |
| 2898 | ADDR is the address to resume at, or -1 for resume where stopped. |
| 2899 | SIGGNAL is the signal to give it, or 0 for none, |
| 2900 | or -1 for act according to how it stopped. |
| 2901 | STEP is nonzero if should trap after one instruction. |
| 2902 | -1 means return after that and print nothing. |
| 2903 | You should probably set various step_... variables |
| 2904 | before calling here, if you are stepping. |
| 2905 | |
| 2906 | You should call clear_proceed_status before calling proceed. */ |
| 2907 | |
| 2908 | void |
| 2909 | proceed (CORE_ADDR addr, enum gdb_signal siggnal) |
| 2910 | { |
| 2911 | struct regcache *regcache; |
| 2912 | struct gdbarch *gdbarch; |
| 2913 | struct thread_info *tp; |
| 2914 | CORE_ADDR pc; |
| 2915 | struct address_space *aspace; |
| 2916 | ptid_t resume_ptid; |
| 2917 | struct execution_control_state ecss; |
| 2918 | struct execution_control_state *ecs = &ecss; |
| 2919 | struct cleanup *old_chain; |
| 2920 | int started; |
| 2921 | |
| 2922 | /* If we're stopped at a fork/vfork, follow the branch set by the |
| 2923 | "set follow-fork-mode" command; otherwise, we'll just proceed |
| 2924 | resuming the current thread. */ |
| 2925 | if (!follow_fork ()) |
| 2926 | { |
| 2927 | /* The target for some reason decided not to resume. */ |
| 2928 | normal_stop (); |
| 2929 | if (target_can_async_p ()) |
| 2930 | inferior_event_handler (INF_EXEC_COMPLETE, NULL); |
| 2931 | return; |
| 2932 | } |
| 2933 | |
| 2934 | /* We'll update this if & when we switch to a new thread. */ |
| 2935 | previous_inferior_ptid = inferior_ptid; |
| 2936 | |
| 2937 | regcache = get_current_regcache (); |
| 2938 | gdbarch = get_regcache_arch (regcache); |
| 2939 | aspace = get_regcache_aspace (regcache); |
| 2940 | pc = regcache_read_pc (regcache); |
| 2941 | tp = inferior_thread (); |
| 2942 | |
| 2943 | /* Fill in with reasonable starting values. */ |
| 2944 | init_thread_stepping_state (tp); |
| 2945 | |
| 2946 | gdb_assert (!thread_is_in_step_over_chain (tp)); |
| 2947 | |
| 2948 | if (addr == (CORE_ADDR) -1) |
| 2949 | { |
| 2950 | if (pc == stop_pc |
| 2951 | && breakpoint_here_p (aspace, pc) == ordinary_breakpoint_here |
| 2952 | && execution_direction != EXEC_REVERSE) |
| 2953 | /* There is a breakpoint at the address we will resume at, |
| 2954 | step one instruction before inserting breakpoints so that |
| 2955 | we do not stop right away (and report a second hit at this |
| 2956 | breakpoint). |
| 2957 | |
| 2958 | Note, we don't do this in reverse, because we won't |
| 2959 | actually be executing the breakpoint insn anyway. |
| 2960 | We'll be (un-)executing the previous instruction. */ |
| 2961 | tp->stepping_over_breakpoint = 1; |
| 2962 | else if (gdbarch_single_step_through_delay_p (gdbarch) |
| 2963 | && gdbarch_single_step_through_delay (gdbarch, |
| 2964 | get_current_frame ())) |
| 2965 | /* We stepped onto an instruction that needs to be stepped |
| 2966 | again before re-inserting the breakpoint, do so. */ |
| 2967 | tp->stepping_over_breakpoint = 1; |
| 2968 | } |
| 2969 | else |
| 2970 | { |
| 2971 | regcache_write_pc (regcache, addr); |
| 2972 | } |
| 2973 | |
| 2974 | if (siggnal != GDB_SIGNAL_DEFAULT) |
| 2975 | tp->suspend.stop_signal = siggnal; |
| 2976 | |
| 2977 | /* Record the interpreter that issued the execution command that |
| 2978 | caused this thread to resume. If the top level interpreter is |
| 2979 | MI/async, and the execution command was a CLI command |
| 2980 | (next/step/etc.), we'll want to print stop event output to the MI |
| 2981 | console channel (the stepped-to line, etc.), as if the user |
| 2982 | entered the execution command on a real GDB console. */ |
| 2983 | tp->control.command_interp = command_interp (); |
| 2984 | |
| 2985 | resume_ptid = user_visible_resume_ptid (tp->control.stepping_command); |
| 2986 | |
| 2987 | /* If an exception is thrown from this point on, make sure to |
| 2988 | propagate GDB's knowledge of the executing state to the |
| 2989 | frontend/user running state. */ |
| 2990 | old_chain = make_cleanup (finish_thread_state_cleanup, &resume_ptid); |
| 2991 | |
| 2992 | /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer |
| 2993 | threads (e.g., we might need to set threads stepping over |
| 2994 | breakpoints first), from the user/frontend's point of view, all |
| 2995 | threads in RESUME_PTID are now running. Unless we're calling an |
| 2996 | inferior function, as in that case we pretend the inferior |
| 2997 | doesn't run at all. */ |
| 2998 | if (!tp->control.in_infcall) |
| 2999 | set_running (resume_ptid, 1); |
| 3000 | |
| 3001 | if (debug_infrun) |
| 3002 | fprintf_unfiltered (gdb_stdlog, |
| 3003 | "infrun: proceed (addr=%s, signal=%s)\n", |
| 3004 | paddress (gdbarch, addr), |
| 3005 | gdb_signal_to_symbol_string (siggnal)); |
| 3006 | |
| 3007 | annotate_starting (); |
| 3008 | |
| 3009 | /* Make sure that output from GDB appears before output from the |
| 3010 | inferior. */ |
| 3011 | gdb_flush (gdb_stdout); |
| 3012 | |
| 3013 | /* In a multi-threaded task we may select another thread and |
| 3014 | then continue or step. |
| 3015 | |
| 3016 | But if a thread that we're resuming had stopped at a breakpoint, |
| 3017 | it will immediately cause another breakpoint stop without any |
| 3018 | execution (i.e. it will report a breakpoint hit incorrectly). So |
| 3019 | we must step over it first. |
| 3020 | |
| 3021 | Look for threads other than the current (TP) that reported a |
| 3022 | breakpoint hit and haven't been resumed yet since. */ |
| 3023 | |
| 3024 | /* If scheduler locking applies, we can avoid iterating over all |
| 3025 | threads. */ |
| 3026 | if (!non_stop && !schedlock_applies (tp)) |
| 3027 | { |
| 3028 | struct thread_info *current = tp; |
| 3029 | |
| 3030 | ALL_NON_EXITED_THREADS (tp) |
| 3031 | { |
| 3032 | /* Ignore the current thread here. It's handled |
| 3033 | afterwards. */ |
| 3034 | if (tp == current) |
| 3035 | continue; |
| 3036 | |
| 3037 | /* Ignore threads of processes we're not resuming. */ |
| 3038 | if (!ptid_match (tp->ptid, resume_ptid)) |
| 3039 | continue; |
| 3040 | |
| 3041 | if (!thread_still_needs_step_over (tp)) |
| 3042 | continue; |
| 3043 | |
| 3044 | gdb_assert (!thread_is_in_step_over_chain (tp)); |
| 3045 | |
| 3046 | if (debug_infrun) |
| 3047 | fprintf_unfiltered (gdb_stdlog, |
| 3048 | "infrun: need to step-over [%s] first\n", |
| 3049 | target_pid_to_str (tp->ptid)); |
| 3050 | |
| 3051 | thread_step_over_chain_enqueue (tp); |
| 3052 | } |
| 3053 | |
| 3054 | tp = current; |
| 3055 | } |
| 3056 | |
| 3057 | /* Enqueue the current thread last, so that we move all other |
| 3058 | threads over their breakpoints first. */ |
| 3059 | if (tp->stepping_over_breakpoint) |
| 3060 | thread_step_over_chain_enqueue (tp); |
| 3061 | |
| 3062 | /* If the thread isn't started, we'll still need to set its prev_pc, |
| 3063 | so that switch_back_to_stepped_thread knows the thread hasn't |
| 3064 | advanced. Must do this before resuming any thread, as in |
| 3065 | all-stop/remote, once we resume we can't send any other packet |
| 3066 | until the target stops again. */ |
| 3067 | tp->prev_pc = regcache_read_pc (regcache); |
| 3068 | |
| 3069 | started = start_step_over (); |
| 3070 | |
| 3071 | if (step_over_info_valid_p ()) |
| 3072 | { |
| 3073 | /* Either this thread started a new in-line step over, or some |
| 3074 | other thread was already doing one. In either case, don't |
| 3075 | resume anything else until the step-over is finished. */ |
| 3076 | } |
| 3077 | else if (started && !target_is_non_stop_p ()) |
| 3078 | { |
| 3079 | /* A new displaced stepping sequence was started. In all-stop, |
| 3080 | we can't talk to the target anymore until it next stops. */ |
| 3081 | } |
| 3082 | else if (!non_stop && target_is_non_stop_p ()) |
| 3083 | { |
| 3084 | /* In all-stop, but the target is always in non-stop mode. |
| 3085 | Start all other threads that are implicitly resumed too. */ |
| 3086 | ALL_NON_EXITED_THREADS (tp) |
| 3087 | { |
| 3088 | /* Ignore threads of processes we're not resuming. */ |
| 3089 | if (!ptid_match (tp->ptid, resume_ptid)) |
| 3090 | continue; |
| 3091 | |
| 3092 | if (tp->resumed) |
| 3093 | { |
| 3094 | if (debug_infrun) |
| 3095 | fprintf_unfiltered (gdb_stdlog, |
| 3096 | "infrun: proceed: [%s] resumed\n", |
| 3097 | target_pid_to_str (tp->ptid)); |
| 3098 | gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p); |
| 3099 | continue; |
| 3100 | } |
| 3101 | |
| 3102 | if (thread_is_in_step_over_chain (tp)) |
| 3103 | { |
| 3104 | if (debug_infrun) |
| 3105 | fprintf_unfiltered (gdb_stdlog, |
| 3106 | "infrun: proceed: [%s] needs step-over\n", |
| 3107 | target_pid_to_str (tp->ptid)); |
| 3108 | continue; |
| 3109 | } |
| 3110 | |
| 3111 | if (debug_infrun) |
| 3112 | fprintf_unfiltered (gdb_stdlog, |
| 3113 | "infrun: proceed: resuming %s\n", |
| 3114 | target_pid_to_str (tp->ptid)); |
| 3115 | |
| 3116 | reset_ecs (ecs, tp); |
| 3117 | switch_to_thread (tp->ptid); |
| 3118 | keep_going_pass_signal (ecs); |
| 3119 | if (!ecs->wait_some_more) |
| 3120 | error (_("Command aborted.")); |
| 3121 | } |
| 3122 | } |
| 3123 | else if (!tp->resumed && !thread_is_in_step_over_chain (tp)) |
| 3124 | { |
| 3125 | /* The thread wasn't started, and isn't queued, run it now. */ |
| 3126 | reset_ecs (ecs, tp); |
| 3127 | switch_to_thread (tp->ptid); |
| 3128 | keep_going_pass_signal (ecs); |
| 3129 | if (!ecs->wait_some_more) |
| 3130 | error (_("Command aborted.")); |
| 3131 | } |
| 3132 | |
| 3133 | discard_cleanups (old_chain); |
| 3134 | |
| 3135 | /* Tell the event loop to wait for it to stop. If the target |
| 3136 | supports asynchronous execution, it'll do this from within |
| 3137 | target_resume. */ |
| 3138 | if (!target_can_async_p ()) |
| 3139 | mark_async_event_handler (infrun_async_inferior_event_token); |
| 3140 | } |
| 3141 | \f |
| 3142 | |
| 3143 | /* Start remote-debugging of a machine over a serial link. */ |
| 3144 | |
| 3145 | void |
| 3146 | start_remote (int from_tty) |
| 3147 | { |
| 3148 | struct inferior *inferior; |
| 3149 | |
| 3150 | inferior = current_inferior (); |
| 3151 | inferior->control.stop_soon = STOP_QUIETLY_REMOTE; |
| 3152 | |
| 3153 | /* Always go on waiting for the target, regardless of the mode. */ |
| 3154 | /* FIXME: cagney/1999-09-23: At present it isn't possible to |
| 3155 | indicate to wait_for_inferior that a target should timeout if |
| 3156 | nothing is returned (instead of just blocking). Because of this, |
| 3157 | targets expecting an immediate response need to, internally, set |
| 3158 | things up so that the target_wait() is forced to eventually |
| 3159 | timeout. */ |
| 3160 | /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to |
| 3161 | differentiate to its caller what the state of the target is after |
| 3162 | the initial open has been performed. Here we're assuming that |
| 3163 | the target has stopped. It should be possible to eventually have |
| 3164 | target_open() return to the caller an indication that the target |
| 3165 | is currently running and GDB state should be set to the same as |
| 3166 | for an async run. */ |
| 3167 | wait_for_inferior (); |
| 3168 | |
| 3169 | /* Now that the inferior has stopped, do any bookkeeping like |
| 3170 | loading shared libraries. We want to do this before normal_stop, |
| 3171 | so that the displayed frame is up to date. */ |
| 3172 | post_create_inferior (¤t_target, from_tty); |
| 3173 | |
| 3174 | normal_stop (); |
| 3175 | } |
| 3176 | |
| 3177 | /* Initialize static vars when a new inferior begins. */ |
| 3178 | |
| 3179 | void |
| 3180 | init_wait_for_inferior (void) |
| 3181 | { |
| 3182 | /* These are meaningless until the first time through wait_for_inferior. */ |
| 3183 | |
| 3184 | breakpoint_init_inferior (inf_starting); |
| 3185 | |
| 3186 | clear_proceed_status (0); |
| 3187 | |
| 3188 | target_last_wait_ptid = minus_one_ptid; |
| 3189 | |
| 3190 | previous_inferior_ptid = inferior_ptid; |
| 3191 | |
| 3192 | /* Discard any skipped inlined frames. */ |
| 3193 | clear_inline_frame_state (minus_one_ptid); |
| 3194 | } |
| 3195 | |
| 3196 | \f |
| 3197 | |
| 3198 | static void handle_inferior_event (struct execution_control_state *ecs); |
| 3199 | |
| 3200 | static void handle_step_into_function (struct gdbarch *gdbarch, |
| 3201 | struct execution_control_state *ecs); |
| 3202 | static void handle_step_into_function_backward (struct gdbarch *gdbarch, |
| 3203 | struct execution_control_state *ecs); |
| 3204 | static void handle_signal_stop (struct execution_control_state *ecs); |
| 3205 | static void check_exception_resume (struct execution_control_state *, |
| 3206 | struct frame_info *); |
| 3207 | |
| 3208 | static void end_stepping_range (struct execution_control_state *ecs); |
| 3209 | static void stop_waiting (struct execution_control_state *ecs); |
| 3210 | static void keep_going (struct execution_control_state *ecs); |
| 3211 | static void process_event_stop_test (struct execution_control_state *ecs); |
| 3212 | static int switch_back_to_stepped_thread (struct execution_control_state *ecs); |
| 3213 | |
| 3214 | /* Callback for iterate over threads. If the thread is stopped, but |
| 3215 | the user/frontend doesn't know about that yet, go through |
| 3216 | normal_stop, as if the thread had just stopped now. ARG points at |
| 3217 | a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If |
| 3218 | ptid_is_pid(PTID) is true, applies to all threads of the process |
| 3219 | pointed at by PTID. Otherwise, apply only to the thread pointed by |
| 3220 | PTID. */ |
| 3221 | |
| 3222 | static int |
| 3223 | infrun_thread_stop_requested_callback (struct thread_info *info, void *arg) |
| 3224 | { |
| 3225 | ptid_t ptid = * (ptid_t *) arg; |
| 3226 | |
| 3227 | if ((ptid_equal (info->ptid, ptid) |
| 3228 | || ptid_equal (minus_one_ptid, ptid) |
| 3229 | || (ptid_is_pid (ptid) |
| 3230 | && ptid_get_pid (ptid) == ptid_get_pid (info->ptid))) |
| 3231 | && is_running (info->ptid) |
| 3232 | && !is_executing (info->ptid)) |
| 3233 | { |
| 3234 | struct cleanup *old_chain; |
| 3235 | struct execution_control_state ecss; |
| 3236 | struct execution_control_state *ecs = &ecss; |
| 3237 | |
| 3238 | memset (ecs, 0, sizeof (*ecs)); |
| 3239 | |
| 3240 | old_chain = make_cleanup_restore_current_thread (); |
| 3241 | |
| 3242 | overlay_cache_invalid = 1; |
| 3243 | /* Flush target cache before starting to handle each event. |
| 3244 | Target was running and cache could be stale. This is just a |
| 3245 | heuristic. Running threads may modify target memory, but we |
| 3246 | don't get any event. */ |
| 3247 | target_dcache_invalidate (); |
| 3248 | |
| 3249 | /* Go through handle_inferior_event/normal_stop, so we always |
| 3250 | have consistent output as if the stop event had been |
| 3251 | reported. */ |
| 3252 | ecs->ptid = info->ptid; |
| 3253 | ecs->event_thread = info; |
| 3254 | ecs->ws.kind = TARGET_WAITKIND_STOPPED; |
| 3255 | ecs->ws.value.sig = GDB_SIGNAL_0; |
| 3256 | |
| 3257 | handle_inferior_event (ecs); |
| 3258 | |
| 3259 | if (!ecs->wait_some_more) |
| 3260 | { |
| 3261 | /* Cancel any running execution command. */ |
| 3262 | thread_cancel_execution_command (info); |
| 3263 | |
| 3264 | normal_stop (); |
| 3265 | } |
| 3266 | |
| 3267 | do_cleanups (old_chain); |
| 3268 | } |
| 3269 | |
| 3270 | return 0; |
| 3271 | } |
| 3272 | |
| 3273 | /* This function is attached as a "thread_stop_requested" observer. |
| 3274 | Cleanup local state that assumed the PTID was to be resumed, and |
| 3275 | report the stop to the frontend. */ |
| 3276 | |
| 3277 | static void |
| 3278 | infrun_thread_stop_requested (ptid_t ptid) |
| 3279 | { |
| 3280 | struct thread_info *tp; |
| 3281 | |
| 3282 | /* PTID was requested to stop. Remove matching threads from the |
| 3283 | step-over queue, so we don't try to resume them |
| 3284 | automatically. */ |
| 3285 | ALL_NON_EXITED_THREADS (tp) |
| 3286 | if (ptid_match (tp->ptid, ptid)) |
| 3287 | { |
| 3288 | if (thread_is_in_step_over_chain (tp)) |
| 3289 | thread_step_over_chain_remove (tp); |
| 3290 | } |
| 3291 | |
| 3292 | iterate_over_threads (infrun_thread_stop_requested_callback, &ptid); |
| 3293 | } |
| 3294 | |
| 3295 | static void |
| 3296 | infrun_thread_thread_exit (struct thread_info *tp, int silent) |
| 3297 | { |
| 3298 | if (ptid_equal (target_last_wait_ptid, tp->ptid)) |
| 3299 | nullify_last_target_wait_ptid (); |
| 3300 | } |
| 3301 | |
| 3302 | /* Delete the step resume, single-step and longjmp/exception resume |
| 3303 | breakpoints of TP. */ |
| 3304 | |
| 3305 | static void |
| 3306 | delete_thread_infrun_breakpoints (struct thread_info *tp) |
| 3307 | { |
| 3308 | delete_step_resume_breakpoint (tp); |
| 3309 | delete_exception_resume_breakpoint (tp); |
| 3310 | delete_single_step_breakpoints (tp); |
| 3311 | } |
| 3312 | |
| 3313 | /* If the target still has execution, call FUNC for each thread that |
| 3314 | just stopped. In all-stop, that's all the non-exited threads; in |
| 3315 | non-stop, that's the current thread, only. */ |
| 3316 | |
| 3317 | typedef void (*for_each_just_stopped_thread_callback_func) |
| 3318 | (struct thread_info *tp); |
| 3319 | |
| 3320 | static void |
| 3321 | for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func) |
| 3322 | { |
| 3323 | if (!target_has_execution || ptid_equal (inferior_ptid, null_ptid)) |
| 3324 | return; |
| 3325 | |
| 3326 | if (target_is_non_stop_p ()) |
| 3327 | { |
| 3328 | /* If in non-stop mode, only the current thread stopped. */ |
| 3329 | func (inferior_thread ()); |
| 3330 | } |
| 3331 | else |
| 3332 | { |
| 3333 | struct thread_info *tp; |
| 3334 | |
| 3335 | /* In all-stop mode, all threads have stopped. */ |
| 3336 | ALL_NON_EXITED_THREADS (tp) |
| 3337 | { |
| 3338 | func (tp); |
| 3339 | } |
| 3340 | } |
| 3341 | } |
| 3342 | |
| 3343 | /* Delete the step resume and longjmp/exception resume breakpoints of |
| 3344 | the threads that just stopped. */ |
| 3345 | |
| 3346 | static void |
| 3347 | delete_just_stopped_threads_infrun_breakpoints (void) |
| 3348 | { |
| 3349 | for_each_just_stopped_thread (delete_thread_infrun_breakpoints); |
| 3350 | } |
| 3351 | |
| 3352 | /* Delete the single-step breakpoints of the threads that just |
| 3353 | stopped. */ |
| 3354 | |
| 3355 | static void |
| 3356 | delete_just_stopped_threads_single_step_breakpoints (void) |
| 3357 | { |
| 3358 | for_each_just_stopped_thread (delete_single_step_breakpoints); |
| 3359 | } |
| 3360 | |
| 3361 | /* A cleanup wrapper. */ |
| 3362 | |
| 3363 | static void |
| 3364 | delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg) |
| 3365 | { |
| 3366 | delete_just_stopped_threads_infrun_breakpoints (); |
| 3367 | } |
| 3368 | |
| 3369 | /* See infrun.h. */ |
| 3370 | |
| 3371 | void |
| 3372 | print_target_wait_results (ptid_t waiton_ptid, ptid_t result_ptid, |
| 3373 | const struct target_waitstatus *ws) |
| 3374 | { |
| 3375 | char *status_string = target_waitstatus_to_string (ws); |
| 3376 | struct ui_file *tmp_stream = mem_fileopen (); |
| 3377 | char *text; |
| 3378 | |
| 3379 | /* The text is split over several lines because it was getting too long. |
| 3380 | Call fprintf_unfiltered (gdb_stdlog) once so that the text is still |
| 3381 | output as a unit; we want only one timestamp printed if debug_timestamp |
| 3382 | is set. */ |
| 3383 | |
| 3384 | fprintf_unfiltered (tmp_stream, |
| 3385 | "infrun: target_wait (%d.%ld.%ld", |
| 3386 | ptid_get_pid (waiton_ptid), |
| 3387 | ptid_get_lwp (waiton_ptid), |
| 3388 | ptid_get_tid (waiton_ptid)); |
| 3389 | if (ptid_get_pid (waiton_ptid) != -1) |
| 3390 | fprintf_unfiltered (tmp_stream, |
| 3391 | " [%s]", target_pid_to_str (waiton_ptid)); |
| 3392 | fprintf_unfiltered (tmp_stream, ", status) =\n"); |
| 3393 | fprintf_unfiltered (tmp_stream, |
| 3394 | "infrun: %d.%ld.%ld [%s],\n", |
| 3395 | ptid_get_pid (result_ptid), |
| 3396 | ptid_get_lwp (result_ptid), |
| 3397 | ptid_get_tid (result_ptid), |
| 3398 | target_pid_to_str (result_ptid)); |
| 3399 | fprintf_unfiltered (tmp_stream, |
| 3400 | "infrun: %s\n", |
| 3401 | status_string); |
| 3402 | |
| 3403 | text = ui_file_xstrdup (tmp_stream, NULL); |
| 3404 | |
| 3405 | /* This uses %s in part to handle %'s in the text, but also to avoid |
| 3406 | a gcc error: the format attribute requires a string literal. */ |
| 3407 | fprintf_unfiltered (gdb_stdlog, "%s", text); |
| 3408 | |
| 3409 | xfree (status_string); |
| 3410 | xfree (text); |
| 3411 | ui_file_delete (tmp_stream); |
| 3412 | } |
| 3413 | |
| 3414 | /* Select a thread at random, out of those which are resumed and have |
| 3415 | had events. */ |
| 3416 | |
| 3417 | static struct thread_info * |
| 3418 | random_pending_event_thread (ptid_t waiton_ptid) |
| 3419 | { |
| 3420 | struct thread_info *event_tp; |
| 3421 | int num_events = 0; |
| 3422 | int random_selector; |
| 3423 | |
| 3424 | /* First see how many events we have. Count only resumed threads |
| 3425 | that have an event pending. */ |
| 3426 | ALL_NON_EXITED_THREADS (event_tp) |
| 3427 | if (ptid_match (event_tp->ptid, waiton_ptid) |
| 3428 | && event_tp->resumed |
| 3429 | && event_tp->suspend.waitstatus_pending_p) |
| 3430 | num_events++; |
| 3431 | |
| 3432 | if (num_events == 0) |
| 3433 | return NULL; |
| 3434 | |
| 3435 | /* Now randomly pick a thread out of those that have had events. */ |
| 3436 | random_selector = (int) |
| 3437 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); |
| 3438 | |
| 3439 | if (debug_infrun && num_events > 1) |
| 3440 | fprintf_unfiltered (gdb_stdlog, |
| 3441 | "infrun: Found %d events, selecting #%d\n", |
| 3442 | num_events, random_selector); |
| 3443 | |
| 3444 | /* Select the Nth thread that has had an event. */ |
| 3445 | ALL_NON_EXITED_THREADS (event_tp) |
| 3446 | if (ptid_match (event_tp->ptid, waiton_ptid) |
| 3447 | && event_tp->resumed |
| 3448 | && event_tp->suspend.waitstatus_pending_p) |
| 3449 | if (random_selector-- == 0) |
| 3450 | break; |
| 3451 | |
| 3452 | return event_tp; |
| 3453 | } |
| 3454 | |
| 3455 | /* Wrapper for target_wait that first checks whether threads have |
| 3456 | pending statuses to report before actually asking the target for |
| 3457 | more events. */ |
| 3458 | |
| 3459 | static ptid_t |
| 3460 | do_target_wait (ptid_t ptid, struct target_waitstatus *status, int options) |
| 3461 | { |
| 3462 | ptid_t event_ptid; |
| 3463 | struct thread_info *tp; |
| 3464 | |
| 3465 | /* First check if there is a resumed thread with a wait status |
| 3466 | pending. */ |
| 3467 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) |
| 3468 | { |
| 3469 | tp = random_pending_event_thread (ptid); |
| 3470 | } |
| 3471 | else |
| 3472 | { |
| 3473 | if (debug_infrun) |
| 3474 | fprintf_unfiltered (gdb_stdlog, |
| 3475 | "infrun: Waiting for specific thread %s.\n", |
| 3476 | target_pid_to_str (ptid)); |
| 3477 | |
| 3478 | /* We have a specific thread to check. */ |
| 3479 | tp = find_thread_ptid (ptid); |
| 3480 | gdb_assert (tp != NULL); |
| 3481 | if (!tp->suspend.waitstatus_pending_p) |
| 3482 | tp = NULL; |
| 3483 | } |
| 3484 | |
| 3485 | if (tp != NULL |
| 3486 | && (tp->suspend.stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT |
| 3487 | || tp->suspend.stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT)) |
| 3488 | { |
| 3489 | struct regcache *regcache = get_thread_regcache (tp->ptid); |
| 3490 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 3491 | CORE_ADDR pc; |
| 3492 | int discard = 0; |
| 3493 | |
| 3494 | pc = regcache_read_pc (regcache); |
| 3495 | |
| 3496 | if (pc != tp->suspend.stop_pc) |
| 3497 | { |
| 3498 | if (debug_infrun) |
| 3499 | fprintf_unfiltered (gdb_stdlog, |
| 3500 | "infrun: PC of %s changed. was=%s, now=%s\n", |
| 3501 | target_pid_to_str (tp->ptid), |
| 3502 | paddress (gdbarch, tp->prev_pc), |
| 3503 | paddress (gdbarch, pc)); |
| 3504 | discard = 1; |
| 3505 | } |
| 3506 | else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
| 3507 | { |
| 3508 | if (debug_infrun) |
| 3509 | fprintf_unfiltered (gdb_stdlog, |
| 3510 | "infrun: previous breakpoint of %s, at %s gone\n", |
| 3511 | target_pid_to_str (tp->ptid), |
| 3512 | paddress (gdbarch, pc)); |
| 3513 | |
| 3514 | discard = 1; |
| 3515 | } |
| 3516 | |
| 3517 | if (discard) |
| 3518 | { |
| 3519 | if (debug_infrun) |
| 3520 | fprintf_unfiltered (gdb_stdlog, |
| 3521 | "infrun: pending event of %s cancelled.\n", |
| 3522 | target_pid_to_str (tp->ptid)); |
| 3523 | |
| 3524 | tp->suspend.waitstatus.kind = TARGET_WAITKIND_SPURIOUS; |
| 3525 | tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON; |
| 3526 | } |
| 3527 | } |
| 3528 | |
| 3529 | if (tp != NULL) |
| 3530 | { |
| 3531 | if (debug_infrun) |
| 3532 | { |
| 3533 | char *statstr; |
| 3534 | |
| 3535 | statstr = target_waitstatus_to_string (&tp->suspend.waitstatus); |
| 3536 | fprintf_unfiltered (gdb_stdlog, |
| 3537 | "infrun: Using pending wait status %s for %s.\n", |
| 3538 | statstr, |
| 3539 | target_pid_to_str (tp->ptid)); |
| 3540 | xfree (statstr); |
| 3541 | } |
| 3542 | |
| 3543 | /* Now that we've selected our final event LWP, un-adjust its PC |
| 3544 | if it was a software breakpoint (and the target doesn't |
| 3545 | always adjust the PC itself). */ |
| 3546 | if (tp->suspend.stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT |
| 3547 | && !target_supports_stopped_by_sw_breakpoint ()) |
| 3548 | { |
| 3549 | struct regcache *regcache; |
| 3550 | struct gdbarch *gdbarch; |
| 3551 | int decr_pc; |
| 3552 | |
| 3553 | regcache = get_thread_regcache (tp->ptid); |
| 3554 | gdbarch = get_regcache_arch (regcache); |
| 3555 | |
| 3556 | decr_pc = gdbarch_decr_pc_after_break (gdbarch); |
| 3557 | if (decr_pc != 0) |
| 3558 | { |
| 3559 | CORE_ADDR pc; |
| 3560 | |
| 3561 | pc = regcache_read_pc (regcache); |
| 3562 | regcache_write_pc (regcache, pc + decr_pc); |
| 3563 | } |
| 3564 | } |
| 3565 | |
| 3566 | tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON; |
| 3567 | *status = tp->suspend.waitstatus; |
| 3568 | tp->suspend.waitstatus_pending_p = 0; |
| 3569 | |
| 3570 | /* Wake up the event loop again, until all pending events are |
| 3571 | processed. */ |
| 3572 | if (target_is_async_p ()) |
| 3573 | mark_async_event_handler (infrun_async_inferior_event_token); |
| 3574 | return tp->ptid; |
| 3575 | } |
| 3576 | |
| 3577 | /* But if we don't find one, we'll have to wait. */ |
| 3578 | |
| 3579 | if (deprecated_target_wait_hook) |
| 3580 | event_ptid = deprecated_target_wait_hook (ptid, status, options); |
| 3581 | else |
| 3582 | event_ptid = target_wait (ptid, status, options); |
| 3583 | |
| 3584 | return event_ptid; |
| 3585 | } |
| 3586 | |
| 3587 | /* Prepare and stabilize the inferior for detaching it. E.g., |
| 3588 | detaching while a thread is displaced stepping is a recipe for |
| 3589 | crashing it, as nothing would readjust the PC out of the scratch |
| 3590 | pad. */ |
| 3591 | |
| 3592 | void |
| 3593 | prepare_for_detach (void) |
| 3594 | { |
| 3595 | struct inferior *inf = current_inferior (); |
| 3596 | ptid_t pid_ptid = pid_to_ptid (inf->pid); |
| 3597 | struct cleanup *old_chain_1; |
| 3598 | struct displaced_step_inferior_state *displaced; |
| 3599 | |
| 3600 | displaced = get_displaced_stepping_state (inf->pid); |
| 3601 | |
| 3602 | /* Is any thread of this process displaced stepping? If not, |
| 3603 | there's nothing else to do. */ |
| 3604 | if (displaced == NULL || ptid_equal (displaced->step_ptid, null_ptid)) |
| 3605 | return; |
| 3606 | |
| 3607 | if (debug_infrun) |
| 3608 | fprintf_unfiltered (gdb_stdlog, |
| 3609 | "displaced-stepping in-process while detaching"); |
| 3610 | |
| 3611 | old_chain_1 = make_cleanup_restore_integer (&inf->detaching); |
| 3612 | inf->detaching = 1; |
| 3613 | |
| 3614 | while (!ptid_equal (displaced->step_ptid, null_ptid)) |
| 3615 | { |
| 3616 | struct cleanup *old_chain_2; |
| 3617 | struct execution_control_state ecss; |
| 3618 | struct execution_control_state *ecs; |
| 3619 | |
| 3620 | ecs = &ecss; |
| 3621 | memset (ecs, 0, sizeof (*ecs)); |
| 3622 | |
| 3623 | overlay_cache_invalid = 1; |
| 3624 | /* Flush target cache before starting to handle each event. |
| 3625 | Target was running and cache could be stale. This is just a |
| 3626 | heuristic. Running threads may modify target memory, but we |
| 3627 | don't get any event. */ |
| 3628 | target_dcache_invalidate (); |
| 3629 | |
| 3630 | ecs->ptid = do_target_wait (pid_ptid, &ecs->ws, 0); |
| 3631 | |
| 3632 | if (debug_infrun) |
| 3633 | print_target_wait_results (pid_ptid, ecs->ptid, &ecs->ws); |
| 3634 | |
| 3635 | /* If an error happens while handling the event, propagate GDB's |
| 3636 | knowledge of the executing state to the frontend/user running |
| 3637 | state. */ |
| 3638 | old_chain_2 = make_cleanup (finish_thread_state_cleanup, |
| 3639 | &minus_one_ptid); |
| 3640 | |
| 3641 | /* Now figure out what to do with the result of the result. */ |
| 3642 | handle_inferior_event (ecs); |
| 3643 | |
| 3644 | /* No error, don't finish the state yet. */ |
| 3645 | discard_cleanups (old_chain_2); |
| 3646 | |
| 3647 | /* Breakpoints and watchpoints are not installed on the target |
| 3648 | at this point, and signals are passed directly to the |
| 3649 | inferior, so this must mean the process is gone. */ |
| 3650 | if (!ecs->wait_some_more) |
| 3651 | { |
| 3652 | discard_cleanups (old_chain_1); |
| 3653 | error (_("Program exited while detaching")); |
| 3654 | } |
| 3655 | } |
| 3656 | |
| 3657 | discard_cleanups (old_chain_1); |
| 3658 | } |
| 3659 | |
| 3660 | /* Wait for control to return from inferior to debugger. |
| 3661 | |
| 3662 | If inferior gets a signal, we may decide to start it up again |
| 3663 | instead of returning. That is why there is a loop in this function. |
| 3664 | When this function actually returns it means the inferior |
| 3665 | should be left stopped and GDB should read more commands. */ |
| 3666 | |
| 3667 | void |
| 3668 | wait_for_inferior (void) |
| 3669 | { |
| 3670 | struct cleanup *old_cleanups; |
| 3671 | struct cleanup *thread_state_chain; |
| 3672 | |
| 3673 | if (debug_infrun) |
| 3674 | fprintf_unfiltered |
| 3675 | (gdb_stdlog, "infrun: wait_for_inferior ()\n"); |
| 3676 | |
| 3677 | old_cleanups |
| 3678 | = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup, |
| 3679 | NULL); |
| 3680 | |
| 3681 | /* If an error happens while handling the event, propagate GDB's |
| 3682 | knowledge of the executing state to the frontend/user running |
| 3683 | state. */ |
| 3684 | thread_state_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid); |
| 3685 | |
| 3686 | while (1) |
| 3687 | { |
| 3688 | struct execution_control_state ecss; |
| 3689 | struct execution_control_state *ecs = &ecss; |
| 3690 | ptid_t waiton_ptid = minus_one_ptid; |
| 3691 | |
| 3692 | memset (ecs, 0, sizeof (*ecs)); |
| 3693 | |
| 3694 | overlay_cache_invalid = 1; |
| 3695 | |
| 3696 | /* Flush target cache before starting to handle each event. |
| 3697 | Target was running and cache could be stale. This is just a |
| 3698 | heuristic. Running threads may modify target memory, but we |
| 3699 | don't get any event. */ |
| 3700 | target_dcache_invalidate (); |
| 3701 | |
| 3702 | ecs->ptid = do_target_wait (waiton_ptid, &ecs->ws, 0); |
| 3703 | |
| 3704 | if (debug_infrun) |
| 3705 | print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws); |
| 3706 | |
| 3707 | /* Now figure out what to do with the result of the result. */ |
| 3708 | handle_inferior_event (ecs); |
| 3709 | |
| 3710 | if (!ecs->wait_some_more) |
| 3711 | break; |
| 3712 | } |
| 3713 | |
| 3714 | /* No error, don't finish the state yet. */ |
| 3715 | discard_cleanups (thread_state_chain); |
| 3716 | |
| 3717 | do_cleanups (old_cleanups); |
| 3718 | } |
| 3719 | |
| 3720 | /* Cleanup that reinstalls the readline callback handler, if the |
| 3721 | target is running in the background. If while handling the target |
| 3722 | event something triggered a secondary prompt, like e.g., a |
| 3723 | pagination prompt, we'll have removed the callback handler (see |
| 3724 | gdb_readline_wrapper_line). Need to do this as we go back to the |
| 3725 | event loop, ready to process further input. Note this has no |
| 3726 | effect if the handler hasn't actually been removed, because calling |
| 3727 | rl_callback_handler_install resets the line buffer, thus losing |
| 3728 | input. */ |
| 3729 | |
| 3730 | static void |
| 3731 | reinstall_readline_callback_handler_cleanup (void *arg) |
| 3732 | { |
| 3733 | if (!interpreter_async) |
| 3734 | { |
| 3735 | /* We're not going back to the top level event loop yet. Don't |
| 3736 | install the readline callback, as it'd prep the terminal, |
| 3737 | readline-style (raw, noecho) (e.g., --batch). We'll install |
| 3738 | it the next time the prompt is displayed, when we're ready |
| 3739 | for input. */ |
| 3740 | return; |
| 3741 | } |
| 3742 | |
| 3743 | if (async_command_editing_p && !sync_execution) |
| 3744 | gdb_rl_callback_handler_reinstall (); |
| 3745 | } |
| 3746 | |
| 3747 | /* Clean up the FSMs of threads that are now stopped. In non-stop, |
| 3748 | that's just the event thread. In all-stop, that's all threads. */ |
| 3749 | |
| 3750 | static void |
| 3751 | clean_up_just_stopped_threads_fsms (struct execution_control_state *ecs) |
| 3752 | { |
| 3753 | struct thread_info *thr = ecs->event_thread; |
| 3754 | |
| 3755 | if (thr != NULL && thr->thread_fsm != NULL) |
| 3756 | thread_fsm_clean_up (thr->thread_fsm); |
| 3757 | |
| 3758 | if (!non_stop) |
| 3759 | { |
| 3760 | ALL_NON_EXITED_THREADS (thr) |
| 3761 | { |
| 3762 | if (thr->thread_fsm == NULL) |
| 3763 | continue; |
| 3764 | if (thr == ecs->event_thread) |
| 3765 | continue; |
| 3766 | |
| 3767 | switch_to_thread (thr->ptid); |
| 3768 | thread_fsm_clean_up (thr->thread_fsm); |
| 3769 | } |
| 3770 | |
| 3771 | if (ecs->event_thread != NULL) |
| 3772 | switch_to_thread (ecs->event_thread->ptid); |
| 3773 | } |
| 3774 | } |
| 3775 | |
| 3776 | /* Asynchronous version of wait_for_inferior. It is called by the |
| 3777 | event loop whenever a change of state is detected on the file |
| 3778 | descriptor corresponding to the target. It can be called more than |
| 3779 | once to complete a single execution command. In such cases we need |
| 3780 | to keep the state in a global variable ECSS. If it is the last time |
| 3781 | that this function is called for a single execution command, then |
| 3782 | report to the user that the inferior has stopped, and do the |
| 3783 | necessary cleanups. */ |
| 3784 | |
| 3785 | void |
| 3786 | fetch_inferior_event (void *client_data) |
| 3787 | { |
| 3788 | struct execution_control_state ecss; |
| 3789 | struct execution_control_state *ecs = &ecss; |
| 3790 | struct cleanup *old_chain = make_cleanup (null_cleanup, NULL); |
| 3791 | struct cleanup *ts_old_chain; |
| 3792 | int was_sync = sync_execution; |
| 3793 | int cmd_done = 0; |
| 3794 | ptid_t waiton_ptid = minus_one_ptid; |
| 3795 | |
| 3796 | memset (ecs, 0, sizeof (*ecs)); |
| 3797 | |
| 3798 | /* End up with readline processing input, if necessary. */ |
| 3799 | make_cleanup (reinstall_readline_callback_handler_cleanup, NULL); |
| 3800 | |
| 3801 | /* We're handling a live event, so make sure we're doing live |
| 3802 | debugging. If we're looking at traceframes while the target is |
| 3803 | running, we're going to need to get back to that mode after |
| 3804 | handling the event. */ |
| 3805 | if (non_stop) |
| 3806 | { |
| 3807 | make_cleanup_restore_current_traceframe (); |
| 3808 | set_current_traceframe (-1); |
| 3809 | } |
| 3810 | |
| 3811 | if (non_stop) |
| 3812 | /* In non-stop mode, the user/frontend should not notice a thread |
| 3813 | switch due to internal events. Make sure we reverse to the |
| 3814 | user selected thread and frame after handling the event and |
| 3815 | running any breakpoint commands. */ |
| 3816 | make_cleanup_restore_current_thread (); |
| 3817 | |
| 3818 | overlay_cache_invalid = 1; |
| 3819 | /* Flush target cache before starting to handle each event. Target |
| 3820 | was running and cache could be stale. This is just a heuristic. |
| 3821 | Running threads may modify target memory, but we don't get any |
| 3822 | event. */ |
| 3823 | target_dcache_invalidate (); |
| 3824 | |
| 3825 | make_cleanup_restore_integer (&execution_direction); |
| 3826 | execution_direction = target_execution_direction (); |
| 3827 | |
| 3828 | ecs->ptid = do_target_wait (waiton_ptid, &ecs->ws, |
| 3829 | target_can_async_p () ? TARGET_WNOHANG : 0); |
| 3830 | |
| 3831 | if (debug_infrun) |
| 3832 | print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws); |
| 3833 | |
| 3834 | /* If an error happens while handling the event, propagate GDB's |
| 3835 | knowledge of the executing state to the frontend/user running |
| 3836 | state. */ |
| 3837 | if (!target_is_non_stop_p ()) |
| 3838 | ts_old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid); |
| 3839 | else |
| 3840 | ts_old_chain = make_cleanup (finish_thread_state_cleanup, &ecs->ptid); |
| 3841 | |
| 3842 | /* Get executed before make_cleanup_restore_current_thread above to apply |
| 3843 | still for the thread which has thrown the exception. */ |
| 3844 | make_bpstat_clear_actions_cleanup (); |
| 3845 | |
| 3846 | make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup, NULL); |
| 3847 | |
| 3848 | /* Now figure out what to do with the result of the result. */ |
| 3849 | handle_inferior_event (ecs); |
| 3850 | |
| 3851 | if (!ecs->wait_some_more) |
| 3852 | { |
| 3853 | struct inferior *inf = find_inferior_ptid (ecs->ptid); |
| 3854 | int should_stop = 1; |
| 3855 | struct thread_info *thr = ecs->event_thread; |
| 3856 | int should_notify_stop = 1; |
| 3857 | |
| 3858 | delete_just_stopped_threads_infrun_breakpoints (); |
| 3859 | |
| 3860 | if (thr != NULL) |
| 3861 | { |
| 3862 | struct thread_fsm *thread_fsm = thr->thread_fsm; |
| 3863 | |
| 3864 | if (thread_fsm != NULL) |
| 3865 | should_stop = thread_fsm_should_stop (thread_fsm); |
| 3866 | } |
| 3867 | |
| 3868 | if (!should_stop) |
| 3869 | { |
| 3870 | keep_going (ecs); |
| 3871 | } |
| 3872 | else |
| 3873 | { |
| 3874 | clean_up_just_stopped_threads_fsms (ecs); |
| 3875 | |
| 3876 | if (thr != NULL && thr->thread_fsm != NULL) |
| 3877 | { |
| 3878 | should_notify_stop |
| 3879 | = thread_fsm_should_notify_stop (thr->thread_fsm); |
| 3880 | } |
| 3881 | |
| 3882 | if (should_notify_stop) |
| 3883 | { |
| 3884 | int proceeded = 0; |
| 3885 | |
| 3886 | /* We may not find an inferior if this was a process exit. */ |
| 3887 | if (inf == NULL || inf->control.stop_soon == NO_STOP_QUIETLY) |
| 3888 | proceeded = normal_stop (); |
| 3889 | |
| 3890 | if (!proceeded) |
| 3891 | { |
| 3892 | inferior_event_handler (INF_EXEC_COMPLETE, NULL); |
| 3893 | cmd_done = 1; |
| 3894 | } |
| 3895 | } |
| 3896 | } |
| 3897 | } |
| 3898 | |
| 3899 | /* No error, don't finish the thread states yet. */ |
| 3900 | discard_cleanups (ts_old_chain); |
| 3901 | |
| 3902 | /* Revert thread and frame. */ |
| 3903 | do_cleanups (old_chain); |
| 3904 | |
| 3905 | /* If the inferior was in sync execution mode, and now isn't, |
| 3906 | restore the prompt (a synchronous execution command has finished, |
| 3907 | and we're ready for input). */ |
| 3908 | if (interpreter_async && was_sync && !sync_execution) |
| 3909 | observer_notify_sync_execution_done (); |
| 3910 | |
| 3911 | if (cmd_done |
| 3912 | && !was_sync |
| 3913 | && exec_done_display_p |
| 3914 | && (ptid_equal (inferior_ptid, null_ptid) |
| 3915 | || !is_running (inferior_ptid))) |
| 3916 | printf_unfiltered (_("completed.\n")); |
| 3917 | } |
| 3918 | |
| 3919 | /* Record the frame and location we're currently stepping through. */ |
| 3920 | void |
| 3921 | set_step_info (struct frame_info *frame, struct symtab_and_line sal) |
| 3922 | { |
| 3923 | struct thread_info *tp = inferior_thread (); |
| 3924 | |
| 3925 | tp->control.step_frame_id = get_frame_id (frame); |
| 3926 | tp->control.step_stack_frame_id = get_stack_frame_id (frame); |
| 3927 | |
| 3928 | tp->current_symtab = sal.symtab; |
| 3929 | tp->current_line = sal.line; |
| 3930 | } |
| 3931 | |
| 3932 | /* Clear context switchable stepping state. */ |
| 3933 | |
| 3934 | void |
| 3935 | init_thread_stepping_state (struct thread_info *tss) |
| 3936 | { |
| 3937 | tss->stepped_breakpoint = 0; |
| 3938 | tss->stepping_over_breakpoint = 0; |
| 3939 | tss->stepping_over_watchpoint = 0; |
| 3940 | tss->step_after_step_resume_breakpoint = 0; |
| 3941 | } |
| 3942 | |
| 3943 | /* Set the cached copy of the last ptid/waitstatus. */ |
| 3944 | |
| 3945 | static void |
| 3946 | set_last_target_status (ptid_t ptid, struct target_waitstatus status) |
| 3947 | { |
| 3948 | target_last_wait_ptid = ptid; |
| 3949 | target_last_waitstatus = status; |
| 3950 | } |
| 3951 | |
| 3952 | /* Return the cached copy of the last pid/waitstatus returned by |
| 3953 | target_wait()/deprecated_target_wait_hook(). The data is actually |
| 3954 | cached by handle_inferior_event(), which gets called immediately |
| 3955 | after target_wait()/deprecated_target_wait_hook(). */ |
| 3956 | |
| 3957 | void |
| 3958 | get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status) |
| 3959 | { |
| 3960 | *ptidp = target_last_wait_ptid; |
| 3961 | *status = target_last_waitstatus; |
| 3962 | } |
| 3963 | |
| 3964 | void |
| 3965 | nullify_last_target_wait_ptid (void) |
| 3966 | { |
| 3967 | target_last_wait_ptid = minus_one_ptid; |
| 3968 | } |
| 3969 | |
| 3970 | /* Switch thread contexts. */ |
| 3971 | |
| 3972 | static void |
| 3973 | context_switch (ptid_t ptid) |
| 3974 | { |
| 3975 | if (debug_infrun && !ptid_equal (ptid, inferior_ptid)) |
| 3976 | { |
| 3977 | fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ", |
| 3978 | target_pid_to_str (inferior_ptid)); |
| 3979 | fprintf_unfiltered (gdb_stdlog, "to %s\n", |
| 3980 | target_pid_to_str (ptid)); |
| 3981 | } |
| 3982 | |
| 3983 | switch_to_thread (ptid); |
| 3984 | } |
| 3985 | |
| 3986 | /* If the target can't tell whether we've hit breakpoints |
| 3987 | (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP, |
| 3988 | check whether that could have been caused by a breakpoint. If so, |
| 3989 | adjust the PC, per gdbarch_decr_pc_after_break. */ |
| 3990 | |
| 3991 | static void |
| 3992 | adjust_pc_after_break (struct thread_info *thread, |
| 3993 | struct target_waitstatus *ws) |
| 3994 | { |
| 3995 | struct regcache *regcache; |
| 3996 | struct gdbarch *gdbarch; |
| 3997 | struct address_space *aspace; |
| 3998 | CORE_ADDR breakpoint_pc, decr_pc; |
| 3999 | |
| 4000 | /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If |
| 4001 | we aren't, just return. |
| 4002 | |
| 4003 | We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not |
| 4004 | affected by gdbarch_decr_pc_after_break. Other waitkinds which are |
| 4005 | implemented by software breakpoints should be handled through the normal |
| 4006 | breakpoint layer. |
| 4007 | |
| 4008 | NOTE drow/2004-01-31: On some targets, breakpoints may generate |
| 4009 | different signals (SIGILL or SIGEMT for instance), but it is less |
| 4010 | clear where the PC is pointing afterwards. It may not match |
| 4011 | gdbarch_decr_pc_after_break. I don't know any specific target that |
| 4012 | generates these signals at breakpoints (the code has been in GDB since at |
| 4013 | least 1992) so I can not guess how to handle them here. |
| 4014 | |
| 4015 | In earlier versions of GDB, a target with |
| 4016 | gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a |
| 4017 | watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any |
| 4018 | target with both of these set in GDB history, and it seems unlikely to be |
| 4019 | correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */ |
| 4020 | |
| 4021 | if (ws->kind != TARGET_WAITKIND_STOPPED) |
| 4022 | return; |
| 4023 | |
| 4024 | if (ws->value.sig != GDB_SIGNAL_TRAP) |
| 4025 | return; |
| 4026 | |
| 4027 | /* In reverse execution, when a breakpoint is hit, the instruction |
| 4028 | under it has already been de-executed. The reported PC always |
| 4029 | points at the breakpoint address, so adjusting it further would |
| 4030 | be wrong. E.g., consider this case on a decr_pc_after_break == 1 |
| 4031 | architecture: |
| 4032 | |
| 4033 | B1 0x08000000 : INSN1 |
| 4034 | B2 0x08000001 : INSN2 |
| 4035 | 0x08000002 : INSN3 |
| 4036 | PC -> 0x08000003 : INSN4 |
| 4037 | |
| 4038 | Say you're stopped at 0x08000003 as above. Reverse continuing |
| 4039 | from that point should hit B2 as below. Reading the PC when the |
| 4040 | SIGTRAP is reported should read 0x08000001 and INSN2 should have |
| 4041 | been de-executed already. |
| 4042 | |
| 4043 | B1 0x08000000 : INSN1 |
| 4044 | B2 PC -> 0x08000001 : INSN2 |
| 4045 | 0x08000002 : INSN3 |
| 4046 | 0x08000003 : INSN4 |
| 4047 | |
| 4048 | We can't apply the same logic as for forward execution, because |
| 4049 | we would wrongly adjust the PC to 0x08000000, since there's a |
| 4050 | breakpoint at PC - 1. We'd then report a hit on B1, although |
| 4051 | INSN1 hadn't been de-executed yet. Doing nothing is the correct |
| 4052 | behaviour. */ |
| 4053 | if (execution_direction == EXEC_REVERSE) |
| 4054 | return; |
| 4055 | |
| 4056 | /* If the target can tell whether the thread hit a SW breakpoint, |
| 4057 | trust it. Targets that can tell also adjust the PC |
| 4058 | themselves. */ |
| 4059 | if (target_supports_stopped_by_sw_breakpoint ()) |
| 4060 | return; |
| 4061 | |
| 4062 | /* Note that relying on whether a breakpoint is planted in memory to |
| 4063 | determine this can fail. E.g,. the breakpoint could have been |
| 4064 | removed since. Or the thread could have been told to step an |
| 4065 | instruction the size of a breakpoint instruction, and only |
| 4066 | _after_ was a breakpoint inserted at its address. */ |
| 4067 | |
| 4068 | /* If this target does not decrement the PC after breakpoints, then |
| 4069 | we have nothing to do. */ |
| 4070 | regcache = get_thread_regcache (thread->ptid); |
| 4071 | gdbarch = get_regcache_arch (regcache); |
| 4072 | |
| 4073 | decr_pc = gdbarch_decr_pc_after_break (gdbarch); |
| 4074 | if (decr_pc == 0) |
| 4075 | return; |
| 4076 | |
| 4077 | aspace = get_regcache_aspace (regcache); |
| 4078 | |
| 4079 | /* Find the location where (if we've hit a breakpoint) the |
| 4080 | breakpoint would be. */ |
| 4081 | breakpoint_pc = regcache_read_pc (regcache) - decr_pc; |
| 4082 | |
| 4083 | /* If the target can't tell whether a software breakpoint triggered, |
| 4084 | fallback to figuring it out based on breakpoints we think were |
| 4085 | inserted in the target, and on whether the thread was stepped or |
| 4086 | continued. */ |
| 4087 | |
| 4088 | /* Check whether there actually is a software breakpoint inserted at |
| 4089 | that location. |
| 4090 | |
| 4091 | If in non-stop mode, a race condition is possible where we've |
| 4092 | removed a breakpoint, but stop events for that breakpoint were |
| 4093 | already queued and arrive later. To suppress those spurious |
| 4094 | SIGTRAPs, we keep a list of such breakpoint locations for a bit, |
| 4095 | and retire them after a number of stop events are reported. Note |
| 4096 | this is an heuristic and can thus get confused. The real fix is |
| 4097 | to get the "stopped by SW BP and needs adjustment" info out of |
| 4098 | the target/kernel (and thus never reach here; see above). */ |
| 4099 | if (software_breakpoint_inserted_here_p (aspace, breakpoint_pc) |
| 4100 | || (target_is_non_stop_p () |
| 4101 | && moribund_breakpoint_here_p (aspace, breakpoint_pc))) |
| 4102 | { |
| 4103 | struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL); |
| 4104 | |
| 4105 | if (record_full_is_used ()) |
| 4106 | record_full_gdb_operation_disable_set (); |
| 4107 | |
| 4108 | /* When using hardware single-step, a SIGTRAP is reported for both |
| 4109 | a completed single-step and a software breakpoint. Need to |
| 4110 | differentiate between the two, as the latter needs adjusting |
| 4111 | but the former does not. |
| 4112 | |
| 4113 | The SIGTRAP can be due to a completed hardware single-step only if |
| 4114 | - we didn't insert software single-step breakpoints |
| 4115 | - this thread is currently being stepped |
| 4116 | |
| 4117 | If any of these events did not occur, we must have stopped due |
| 4118 | to hitting a software breakpoint, and have to back up to the |
| 4119 | breakpoint address. |
| 4120 | |
| 4121 | As a special case, we could have hardware single-stepped a |
| 4122 | software breakpoint. In this case (prev_pc == breakpoint_pc), |
| 4123 | we also need to back up to the breakpoint address. */ |
| 4124 | |
| 4125 | if (thread_has_single_step_breakpoints_set (thread) |
| 4126 | || !currently_stepping (thread) |
| 4127 | || (thread->stepped_breakpoint |
| 4128 | && thread->prev_pc == breakpoint_pc)) |
| 4129 | regcache_write_pc (regcache, breakpoint_pc); |
| 4130 | |
| 4131 | do_cleanups (old_cleanups); |
| 4132 | } |
| 4133 | } |
| 4134 | |
| 4135 | static int |
| 4136 | stepped_in_from (struct frame_info *frame, struct frame_id step_frame_id) |
| 4137 | { |
| 4138 | for (frame = get_prev_frame (frame); |
| 4139 | frame != NULL; |
| 4140 | frame = get_prev_frame (frame)) |
| 4141 | { |
| 4142 | if (frame_id_eq (get_frame_id (frame), step_frame_id)) |
| 4143 | return 1; |
| 4144 | if (get_frame_type (frame) != INLINE_FRAME) |
| 4145 | break; |
| 4146 | } |
| 4147 | |
| 4148 | return 0; |
| 4149 | } |
| 4150 | |
| 4151 | /* Auxiliary function that handles syscall entry/return events. |
| 4152 | It returns 1 if the inferior should keep going (and GDB |
| 4153 | should ignore the event), or 0 if the event deserves to be |
| 4154 | processed. */ |
| 4155 | |
| 4156 | static int |
| 4157 | handle_syscall_event (struct execution_control_state *ecs) |
| 4158 | { |
| 4159 | struct regcache *regcache; |
| 4160 | int syscall_number; |
| 4161 | |
| 4162 | if (!ptid_equal (ecs->ptid, inferior_ptid)) |
| 4163 | context_switch (ecs->ptid); |
| 4164 | |
| 4165 | regcache = get_thread_regcache (ecs->ptid); |
| 4166 | syscall_number = ecs->ws.value.syscall_number; |
| 4167 | stop_pc = regcache_read_pc (regcache); |
| 4168 | |
| 4169 | if (catch_syscall_enabled () > 0 |
| 4170 | && catching_syscall_number (syscall_number) > 0) |
| 4171 | { |
| 4172 | if (debug_infrun) |
| 4173 | fprintf_unfiltered (gdb_stdlog, "infrun: syscall number = '%d'\n", |
| 4174 | syscall_number); |
| 4175 | |
| 4176 | ecs->event_thread->control.stop_bpstat |
| 4177 | = bpstat_stop_status (get_regcache_aspace (regcache), |
| 4178 | stop_pc, ecs->ptid, &ecs->ws); |
| 4179 | |
| 4180 | if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat)) |
| 4181 | { |
| 4182 | /* Catchpoint hit. */ |
| 4183 | return 0; |
| 4184 | } |
| 4185 | } |
| 4186 | |
| 4187 | /* If no catchpoint triggered for this, then keep going. */ |
| 4188 | keep_going (ecs); |
| 4189 | return 1; |
| 4190 | } |
| 4191 | |
| 4192 | /* Lazily fill in the execution_control_state's stop_func_* fields. */ |
| 4193 | |
| 4194 | static void |
| 4195 | fill_in_stop_func (struct gdbarch *gdbarch, |
| 4196 | struct execution_control_state *ecs) |
| 4197 | { |
| 4198 | if (!ecs->stop_func_filled_in) |
| 4199 | { |
| 4200 | /* Don't care about return value; stop_func_start and stop_func_name |
| 4201 | will both be 0 if it doesn't work. */ |
| 4202 | find_pc_partial_function (stop_pc, &ecs->stop_func_name, |
| 4203 | &ecs->stop_func_start, &ecs->stop_func_end); |
| 4204 | ecs->stop_func_start |
| 4205 | += gdbarch_deprecated_function_start_offset (gdbarch); |
| 4206 | |
| 4207 | if (gdbarch_skip_entrypoint_p (gdbarch)) |
| 4208 | ecs->stop_func_start = gdbarch_skip_entrypoint (gdbarch, |
| 4209 | ecs->stop_func_start); |
| 4210 | |
| 4211 | ecs->stop_func_filled_in = 1; |
| 4212 | } |
| 4213 | } |
| 4214 | |
| 4215 | |
| 4216 | /* Return the STOP_SOON field of the inferior pointed at by PTID. */ |
| 4217 | |
| 4218 | static enum stop_kind |
| 4219 | get_inferior_stop_soon (ptid_t ptid) |
| 4220 | { |
| 4221 | struct inferior *inf = find_inferior_ptid (ptid); |
| 4222 | |
| 4223 | gdb_assert (inf != NULL); |
| 4224 | return inf->control.stop_soon; |
| 4225 | } |
| 4226 | |
| 4227 | /* Wait for one event. Store the resulting waitstatus in WS, and |
| 4228 | return the event ptid. */ |
| 4229 | |
| 4230 | static ptid_t |
| 4231 | wait_one (struct target_waitstatus *ws) |
| 4232 | { |
| 4233 | ptid_t event_ptid; |
| 4234 | ptid_t wait_ptid = minus_one_ptid; |
| 4235 | |
| 4236 | overlay_cache_invalid = 1; |
| 4237 | |
| 4238 | /* Flush target cache before starting to handle each event. |
| 4239 | Target was running and cache could be stale. This is just a |
| 4240 | heuristic. Running threads may modify target memory, but we |
| 4241 | don't get any event. */ |
| 4242 | target_dcache_invalidate (); |
| 4243 | |
| 4244 | if (deprecated_target_wait_hook) |
| 4245 | event_ptid = deprecated_target_wait_hook (wait_ptid, ws, 0); |
| 4246 | else |
| 4247 | event_ptid = target_wait (wait_ptid, ws, 0); |
| 4248 | |
| 4249 | if (debug_infrun) |
| 4250 | print_target_wait_results (wait_ptid, event_ptid, ws); |
| 4251 | |
| 4252 | return event_ptid; |
| 4253 | } |
| 4254 | |
| 4255 | /* Generate a wrapper for target_stopped_by_REASON that works on PTID |
| 4256 | instead of the current thread. */ |
| 4257 | #define THREAD_STOPPED_BY(REASON) \ |
| 4258 | static int \ |
| 4259 | thread_stopped_by_ ## REASON (ptid_t ptid) \ |
| 4260 | { \ |
| 4261 | struct cleanup *old_chain; \ |
| 4262 | int res; \ |
| 4263 | \ |
| 4264 | old_chain = save_inferior_ptid (); \ |
| 4265 | inferior_ptid = ptid; \ |
| 4266 | \ |
| 4267 | res = target_stopped_by_ ## REASON (); \ |
| 4268 | \ |
| 4269 | do_cleanups (old_chain); \ |
| 4270 | \ |
| 4271 | return res; \ |
| 4272 | } |
| 4273 | |
| 4274 | /* Generate thread_stopped_by_watchpoint. */ |
| 4275 | THREAD_STOPPED_BY (watchpoint) |
| 4276 | /* Generate thread_stopped_by_sw_breakpoint. */ |
| 4277 | THREAD_STOPPED_BY (sw_breakpoint) |
| 4278 | /* Generate thread_stopped_by_hw_breakpoint. */ |
| 4279 | THREAD_STOPPED_BY (hw_breakpoint) |
| 4280 | |
| 4281 | /* Cleanups that switches to the PTID pointed at by PTID_P. */ |
| 4282 | |
| 4283 | static void |
| 4284 | switch_to_thread_cleanup (void *ptid_p) |
| 4285 | { |
| 4286 | ptid_t ptid = *(ptid_t *) ptid_p; |
| 4287 | |
| 4288 | switch_to_thread (ptid); |
| 4289 | } |
| 4290 | |
| 4291 | /* Save the thread's event and stop reason to process it later. */ |
| 4292 | |
| 4293 | static void |
| 4294 | save_waitstatus (struct thread_info *tp, struct target_waitstatus *ws) |
| 4295 | { |
| 4296 | struct regcache *regcache; |
| 4297 | struct address_space *aspace; |
| 4298 | |
| 4299 | if (debug_infrun) |
| 4300 | { |
| 4301 | char *statstr; |
| 4302 | |
| 4303 | statstr = target_waitstatus_to_string (ws); |
| 4304 | fprintf_unfiltered (gdb_stdlog, |
| 4305 | "infrun: saving status %s for %d.%ld.%ld\n", |
| 4306 | statstr, |
| 4307 | ptid_get_pid (tp->ptid), |
| 4308 | ptid_get_lwp (tp->ptid), |
| 4309 | ptid_get_tid (tp->ptid)); |
| 4310 | xfree (statstr); |
| 4311 | } |
| 4312 | |
| 4313 | /* Record for later. */ |
| 4314 | tp->suspend.waitstatus = *ws; |
| 4315 | tp->suspend.waitstatus_pending_p = 1; |
| 4316 | |
| 4317 | regcache = get_thread_regcache (tp->ptid); |
| 4318 | aspace = get_regcache_aspace (regcache); |
| 4319 | |
| 4320 | if (ws->kind == TARGET_WAITKIND_STOPPED |
| 4321 | && ws->value.sig == GDB_SIGNAL_TRAP) |
| 4322 | { |
| 4323 | CORE_ADDR pc = regcache_read_pc (regcache); |
| 4324 | |
| 4325 | adjust_pc_after_break (tp, &tp->suspend.waitstatus); |
| 4326 | |
| 4327 | if (thread_stopped_by_watchpoint (tp->ptid)) |
| 4328 | { |
| 4329 | tp->suspend.stop_reason |
| 4330 | = TARGET_STOPPED_BY_WATCHPOINT; |
| 4331 | } |
| 4332 | else if (target_supports_stopped_by_sw_breakpoint () |
| 4333 | && thread_stopped_by_sw_breakpoint (tp->ptid)) |
| 4334 | { |
| 4335 | tp->suspend.stop_reason |
| 4336 | = TARGET_STOPPED_BY_SW_BREAKPOINT; |
| 4337 | } |
| 4338 | else if (target_supports_stopped_by_hw_breakpoint () |
| 4339 | && thread_stopped_by_hw_breakpoint (tp->ptid)) |
| 4340 | { |
| 4341 | tp->suspend.stop_reason |
| 4342 | = TARGET_STOPPED_BY_HW_BREAKPOINT; |
| 4343 | } |
| 4344 | else if (!target_supports_stopped_by_hw_breakpoint () |
| 4345 | && hardware_breakpoint_inserted_here_p (aspace, |
| 4346 | pc)) |
| 4347 | { |
| 4348 | tp->suspend.stop_reason |
| 4349 | = TARGET_STOPPED_BY_HW_BREAKPOINT; |
| 4350 | } |
| 4351 | else if (!target_supports_stopped_by_sw_breakpoint () |
| 4352 | && software_breakpoint_inserted_here_p (aspace, |
| 4353 | pc)) |
| 4354 | { |
| 4355 | tp->suspend.stop_reason |
| 4356 | = TARGET_STOPPED_BY_SW_BREAKPOINT; |
| 4357 | } |
| 4358 | else if (!thread_has_single_step_breakpoints_set (tp) |
| 4359 | && currently_stepping (tp)) |
| 4360 | { |
| 4361 | tp->suspend.stop_reason |
| 4362 | = TARGET_STOPPED_BY_SINGLE_STEP; |
| 4363 | } |
| 4364 | } |
| 4365 | } |
| 4366 | |
| 4367 | /* Stop all threads. */ |
| 4368 | |
| 4369 | static void |
| 4370 | stop_all_threads (void) |
| 4371 | { |
| 4372 | /* We may need multiple passes to discover all threads. */ |
| 4373 | int pass; |
| 4374 | int iterations = 0; |
| 4375 | ptid_t entry_ptid; |
| 4376 | struct cleanup *old_chain; |
| 4377 | |
| 4378 | gdb_assert (target_is_non_stop_p ()); |
| 4379 | |
| 4380 | if (debug_infrun) |
| 4381 | fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads\n"); |
| 4382 | |
| 4383 | entry_ptid = inferior_ptid; |
| 4384 | old_chain = make_cleanup (switch_to_thread_cleanup, &entry_ptid); |
| 4385 | |
| 4386 | /* Request threads to stop, and then wait for the stops. Because |
| 4387 | threads we already know about can spawn more threads while we're |
| 4388 | trying to stop them, and we only learn about new threads when we |
| 4389 | update the thread list, do this in a loop, and keep iterating |
| 4390 | until two passes find no threads that need to be stopped. */ |
| 4391 | for (pass = 0; pass < 2; pass++, iterations++) |
| 4392 | { |
| 4393 | if (debug_infrun) |
| 4394 | fprintf_unfiltered (gdb_stdlog, |
| 4395 | "infrun: stop_all_threads, pass=%d, " |
| 4396 | "iterations=%d\n", pass, iterations); |
| 4397 | while (1) |
| 4398 | { |
| 4399 | ptid_t event_ptid; |
| 4400 | struct target_waitstatus ws; |
| 4401 | int need_wait = 0; |
| 4402 | struct thread_info *t; |
| 4403 | |
| 4404 | update_thread_list (); |
| 4405 | |
| 4406 | /* Go through all threads looking for threads that we need |
| 4407 | to tell the target to stop. */ |
| 4408 | ALL_NON_EXITED_THREADS (t) |
| 4409 | { |
| 4410 | if (t->executing) |
| 4411 | { |
| 4412 | /* If already stopping, don't request a stop again. |
| 4413 | We just haven't seen the notification yet. */ |
| 4414 | if (!t->stop_requested) |
| 4415 | { |
| 4416 | if (debug_infrun) |
| 4417 | fprintf_unfiltered (gdb_stdlog, |
| 4418 | "infrun: %s executing, " |
| 4419 | "need stop\n", |
| 4420 | target_pid_to_str (t->ptid)); |
| 4421 | target_stop (t->ptid); |
| 4422 | t->stop_requested = 1; |
| 4423 | } |
| 4424 | else |
| 4425 | { |
| 4426 | if (debug_infrun) |
| 4427 | fprintf_unfiltered (gdb_stdlog, |
| 4428 | "infrun: %s executing, " |
| 4429 | "already stopping\n", |
| 4430 | target_pid_to_str (t->ptid)); |
| 4431 | } |
| 4432 | |
| 4433 | if (t->stop_requested) |
| 4434 | need_wait = 1; |
| 4435 | } |
| 4436 | else |
| 4437 | { |
| 4438 | if (debug_infrun) |
| 4439 | fprintf_unfiltered (gdb_stdlog, |
| 4440 | "infrun: %s not executing\n", |
| 4441 | target_pid_to_str (t->ptid)); |
| 4442 | |
| 4443 | /* The thread may be not executing, but still be |
| 4444 | resumed with a pending status to process. */ |
| 4445 | t->resumed = 0; |
| 4446 | } |
| 4447 | } |
| 4448 | |
| 4449 | if (!need_wait) |
| 4450 | break; |
| 4451 | |
| 4452 | /* If we find new threads on the second iteration, restart |
| 4453 | over. We want to see two iterations in a row with all |
| 4454 | threads stopped. */ |
| 4455 | if (pass > 0) |
| 4456 | pass = -1; |
| 4457 | |
| 4458 | event_ptid = wait_one (&ws); |
| 4459 | if (ws.kind == TARGET_WAITKIND_NO_RESUMED) |
| 4460 | { |
| 4461 | /* All resumed threads exited. */ |
| 4462 | } |
| 4463 | else if (ws.kind == TARGET_WAITKIND_EXITED |
| 4464 | || ws.kind == TARGET_WAITKIND_SIGNALLED) |
| 4465 | { |
| 4466 | if (debug_infrun) |
| 4467 | { |
| 4468 | ptid_t ptid = pid_to_ptid (ws.value.integer); |
| 4469 | |
| 4470 | fprintf_unfiltered (gdb_stdlog, |
| 4471 | "infrun: %s exited while " |
| 4472 | "stopping threads\n", |
| 4473 | target_pid_to_str (ptid)); |
| 4474 | } |
| 4475 | } |
| 4476 | else |
| 4477 | { |
| 4478 | t = find_thread_ptid (event_ptid); |
| 4479 | if (t == NULL) |
| 4480 | t = add_thread (event_ptid); |
| 4481 | |
| 4482 | t->stop_requested = 0; |
| 4483 | t->executing = 0; |
| 4484 | t->resumed = 0; |
| 4485 | t->control.may_range_step = 0; |
| 4486 | |
| 4487 | if (ws.kind == TARGET_WAITKIND_STOPPED |
| 4488 | && ws.value.sig == GDB_SIGNAL_0) |
| 4489 | { |
| 4490 | /* We caught the event that we intended to catch, so |
| 4491 | there's no event pending. */ |
| 4492 | t->suspend.waitstatus.kind = TARGET_WAITKIND_IGNORE; |
| 4493 | t->suspend.waitstatus_pending_p = 0; |
| 4494 | |
| 4495 | if (displaced_step_fixup (t->ptid, GDB_SIGNAL_0) < 0) |
| 4496 | { |
| 4497 | /* Add it back to the step-over queue. */ |
| 4498 | if (debug_infrun) |
| 4499 | { |
| 4500 | fprintf_unfiltered (gdb_stdlog, |
| 4501 | "infrun: displaced-step of %s " |
| 4502 | "canceled: adding back to the " |
| 4503 | "step-over queue\n", |
| 4504 | target_pid_to_str (t->ptid)); |
| 4505 | } |
| 4506 | t->control.trap_expected = 0; |
| 4507 | thread_step_over_chain_enqueue (t); |
| 4508 | } |
| 4509 | } |
| 4510 | else |
| 4511 | { |
| 4512 | enum gdb_signal sig; |
| 4513 | struct regcache *regcache; |
| 4514 | struct address_space *aspace; |
| 4515 | |
| 4516 | if (debug_infrun) |
| 4517 | { |
| 4518 | char *statstr; |
| 4519 | |
| 4520 | statstr = target_waitstatus_to_string (&ws); |
| 4521 | fprintf_unfiltered (gdb_stdlog, |
| 4522 | "infrun: target_wait %s, saving " |
| 4523 | "status for %d.%ld.%ld\n", |
| 4524 | statstr, |
| 4525 | ptid_get_pid (t->ptid), |
| 4526 | ptid_get_lwp (t->ptid), |
| 4527 | ptid_get_tid (t->ptid)); |
| 4528 | xfree (statstr); |
| 4529 | } |
| 4530 | |
| 4531 | /* Record for later. */ |
| 4532 | save_waitstatus (t, &ws); |
| 4533 | |
| 4534 | sig = (ws.kind == TARGET_WAITKIND_STOPPED |
| 4535 | ? ws.value.sig : GDB_SIGNAL_0); |
| 4536 | |
| 4537 | if (displaced_step_fixup (t->ptid, sig) < 0) |
| 4538 | { |
| 4539 | /* Add it back to the step-over queue. */ |
| 4540 | t->control.trap_expected = 0; |
| 4541 | thread_step_over_chain_enqueue (t); |
| 4542 | } |
| 4543 | |
| 4544 | regcache = get_thread_regcache (t->ptid); |
| 4545 | t->suspend.stop_pc = regcache_read_pc (regcache); |
| 4546 | |
| 4547 | if (debug_infrun) |
| 4548 | { |
| 4549 | fprintf_unfiltered (gdb_stdlog, |
| 4550 | "infrun: saved stop_pc=%s for %s " |
| 4551 | "(currently_stepping=%d)\n", |
| 4552 | paddress (target_gdbarch (), |
| 4553 | t->suspend.stop_pc), |
| 4554 | target_pid_to_str (t->ptid), |
| 4555 | currently_stepping (t)); |
| 4556 | } |
| 4557 | } |
| 4558 | } |
| 4559 | } |
| 4560 | } |
| 4561 | |
| 4562 | do_cleanups (old_chain); |
| 4563 | |
| 4564 | if (debug_infrun) |
| 4565 | fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads done\n"); |
| 4566 | } |
| 4567 | |
| 4568 | /* Given an execution control state that has been freshly filled in by |
| 4569 | an event from the inferior, figure out what it means and take |
| 4570 | appropriate action. |
| 4571 | |
| 4572 | The alternatives are: |
| 4573 | |
| 4574 | 1) stop_waiting and return; to really stop and return to the |
| 4575 | debugger. |
| 4576 | |
| 4577 | 2) keep_going and return; to wait for the next event (set |
| 4578 | ecs->event_thread->stepping_over_breakpoint to 1 to single step |
| 4579 | once). */ |
| 4580 | |
| 4581 | static void |
| 4582 | handle_inferior_event_1 (struct execution_control_state *ecs) |
| 4583 | { |
| 4584 | enum stop_kind stop_soon; |
| 4585 | |
| 4586 | if (ecs->ws.kind == TARGET_WAITKIND_IGNORE) |
| 4587 | { |
| 4588 | /* We had an event in the inferior, but we are not interested in |
| 4589 | handling it at this level. The lower layers have already |
| 4590 | done what needs to be done, if anything. |
| 4591 | |
| 4592 | One of the possible circumstances for this is when the |
| 4593 | inferior produces output for the console. The inferior has |
| 4594 | not stopped, and we are ignoring the event. Another possible |
| 4595 | circumstance is any event which the lower level knows will be |
| 4596 | reported multiple times without an intervening resume. */ |
| 4597 | if (debug_infrun) |
| 4598 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n"); |
| 4599 | prepare_to_wait (ecs); |
| 4600 | return; |
| 4601 | } |
| 4602 | |
| 4603 | if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED |
| 4604 | && target_can_async_p () && !sync_execution) |
| 4605 | { |
| 4606 | /* There were no unwaited-for children left in the target, but, |
| 4607 | we're not synchronously waiting for events either. Just |
| 4608 | ignore. Otherwise, if we were running a synchronous |
| 4609 | execution command, we need to cancel it and give the user |
| 4610 | back the terminal. */ |
| 4611 | if (debug_infrun) |
| 4612 | fprintf_unfiltered (gdb_stdlog, |
| 4613 | "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n"); |
| 4614 | prepare_to_wait (ecs); |
| 4615 | return; |
| 4616 | } |
| 4617 | |
| 4618 | /* Cache the last pid/waitstatus. */ |
| 4619 | set_last_target_status (ecs->ptid, ecs->ws); |
| 4620 | |
| 4621 | /* Always clear state belonging to the previous time we stopped. */ |
| 4622 | stop_stack_dummy = STOP_NONE; |
| 4623 | |
| 4624 | if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED) |
| 4625 | { |
| 4626 | /* No unwaited-for children left. IOW, all resumed children |
| 4627 | have exited. */ |
| 4628 | if (debug_infrun) |
| 4629 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_RESUMED\n"); |
| 4630 | |
| 4631 | stop_print_frame = 0; |
| 4632 | stop_waiting (ecs); |
| 4633 | return; |
| 4634 | } |
| 4635 | |
| 4636 | if (ecs->ws.kind != TARGET_WAITKIND_EXITED |
| 4637 | && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED) |
| 4638 | { |
| 4639 | ecs->event_thread = find_thread_ptid (ecs->ptid); |
| 4640 | /* If it's a new thread, add it to the thread database. */ |
| 4641 | if (ecs->event_thread == NULL) |
| 4642 | ecs->event_thread = add_thread (ecs->ptid); |
| 4643 | |
| 4644 | /* Disable range stepping. If the next step request could use a |
| 4645 | range, this will be end up re-enabled then. */ |
| 4646 | ecs->event_thread->control.may_range_step = 0; |
| 4647 | } |
| 4648 | |
| 4649 | /* Dependent on valid ECS->EVENT_THREAD. */ |
| 4650 | adjust_pc_after_break (ecs->event_thread, &ecs->ws); |
| 4651 | |
| 4652 | /* Dependent on the current PC value modified by adjust_pc_after_break. */ |
| 4653 | reinit_frame_cache (); |
| 4654 | |
| 4655 | breakpoint_retire_moribund (); |
| 4656 | |
| 4657 | /* First, distinguish signals caused by the debugger from signals |
| 4658 | that have to do with the program's own actions. Note that |
| 4659 | breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending |
| 4660 | on the operating system version. Here we detect when a SIGILL or |
| 4661 | SIGEMT is really a breakpoint and change it to SIGTRAP. We do |
| 4662 | something similar for SIGSEGV, since a SIGSEGV will be generated |
| 4663 | when we're trying to execute a breakpoint instruction on a |
| 4664 | non-executable stack. This happens for call dummy breakpoints |
| 4665 | for architectures like SPARC that place call dummies on the |
| 4666 | stack. */ |
| 4667 | if (ecs->ws.kind == TARGET_WAITKIND_STOPPED |
| 4668 | && (ecs->ws.value.sig == GDB_SIGNAL_ILL |
| 4669 | || ecs->ws.value.sig == GDB_SIGNAL_SEGV |
| 4670 | || ecs->ws.value.sig == GDB_SIGNAL_EMT)) |
| 4671 | { |
| 4672 | struct regcache *regcache = get_thread_regcache (ecs->ptid); |
| 4673 | |
| 4674 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), |
| 4675 | regcache_read_pc (regcache))) |
| 4676 | { |
| 4677 | if (debug_infrun) |
| 4678 | fprintf_unfiltered (gdb_stdlog, |
| 4679 | "infrun: Treating signal as SIGTRAP\n"); |
| 4680 | ecs->ws.value.sig = GDB_SIGNAL_TRAP; |
| 4681 | } |
| 4682 | } |
| 4683 | |
| 4684 | /* Mark the non-executing threads accordingly. In all-stop, all |
| 4685 | threads of all processes are stopped when we get any event |
| 4686 | reported. In non-stop mode, only the event thread stops. */ |
| 4687 | { |
| 4688 | ptid_t mark_ptid; |
| 4689 | |
| 4690 | if (!target_is_non_stop_p ()) |
| 4691 | mark_ptid = minus_one_ptid; |
| 4692 | else if (ecs->ws.kind == TARGET_WAITKIND_SIGNALLED |
| 4693 | || ecs->ws.kind == TARGET_WAITKIND_EXITED) |
| 4694 | { |
| 4695 | /* If we're handling a process exit in non-stop mode, even |
| 4696 | though threads haven't been deleted yet, one would think |
| 4697 | that there is nothing to do, as threads of the dead process |
| 4698 | will be soon deleted, and threads of any other process were |
| 4699 | left running. However, on some targets, threads survive a |
| 4700 | process exit event. E.g., for the "checkpoint" command, |
| 4701 | when the current checkpoint/fork exits, linux-fork.c |
| 4702 | automatically switches to another fork from within |
| 4703 | target_mourn_inferior, by associating the same |
| 4704 | inferior/thread to another fork. We haven't mourned yet at |
| 4705 | this point, but we must mark any threads left in the |
| 4706 | process as not-executing so that finish_thread_state marks |
| 4707 | them stopped (in the user's perspective) if/when we present |
| 4708 | the stop to the user. */ |
| 4709 | mark_ptid = pid_to_ptid (ptid_get_pid (ecs->ptid)); |
| 4710 | } |
| 4711 | else |
| 4712 | mark_ptid = ecs->ptid; |
| 4713 | |
| 4714 | set_executing (mark_ptid, 0); |
| 4715 | |
| 4716 | /* Likewise the resumed flag. */ |
| 4717 | set_resumed (mark_ptid, 0); |
| 4718 | } |
| 4719 | |
| 4720 | switch (ecs->ws.kind) |
| 4721 | { |
| 4722 | case TARGET_WAITKIND_LOADED: |
| 4723 | if (debug_infrun) |
| 4724 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n"); |
| 4725 | if (!ptid_equal (ecs->ptid, inferior_ptid)) |
| 4726 | context_switch (ecs->ptid); |
| 4727 | /* Ignore gracefully during startup of the inferior, as it might |
| 4728 | be the shell which has just loaded some objects, otherwise |
| 4729 | add the symbols for the newly loaded objects. Also ignore at |
| 4730 | the beginning of an attach or remote session; we will query |
| 4731 | the full list of libraries once the connection is |
| 4732 | established. */ |
| 4733 | |
| 4734 | stop_soon = get_inferior_stop_soon (ecs->ptid); |
| 4735 | if (stop_soon == NO_STOP_QUIETLY) |
| 4736 | { |
| 4737 | struct regcache *regcache; |
| 4738 | |
| 4739 | regcache = get_thread_regcache (ecs->ptid); |
| 4740 | |
| 4741 | handle_solib_event (); |
| 4742 | |
| 4743 | ecs->event_thread->control.stop_bpstat |
| 4744 | = bpstat_stop_status (get_regcache_aspace (regcache), |
| 4745 | stop_pc, ecs->ptid, &ecs->ws); |
| 4746 | |
| 4747 | if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat)) |
| 4748 | { |
| 4749 | /* A catchpoint triggered. */ |
| 4750 | process_event_stop_test (ecs); |
| 4751 | return; |
| 4752 | } |
| 4753 | |
| 4754 | /* If requested, stop when the dynamic linker notifies |
| 4755 | gdb of events. This allows the user to get control |
| 4756 | and place breakpoints in initializer routines for |
| 4757 | dynamically loaded objects (among other things). */ |
| 4758 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 4759 | if (stop_on_solib_events) |
| 4760 | { |
| 4761 | /* Make sure we print "Stopped due to solib-event" in |
| 4762 | normal_stop. */ |
| 4763 | stop_print_frame = 1; |
| 4764 | |
| 4765 | stop_waiting (ecs); |
| 4766 | return; |
| 4767 | } |
| 4768 | } |
| 4769 | |
| 4770 | /* If we are skipping through a shell, or through shared library |
| 4771 | loading that we aren't interested in, resume the program. If |
| 4772 | we're running the program normally, also resume. */ |
| 4773 | if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY) |
| 4774 | { |
| 4775 | /* Loading of shared libraries might have changed breakpoint |
| 4776 | addresses. Make sure new breakpoints are inserted. */ |
| 4777 | if (stop_soon == NO_STOP_QUIETLY) |
| 4778 | insert_breakpoints (); |
| 4779 | resume (GDB_SIGNAL_0); |
| 4780 | prepare_to_wait (ecs); |
| 4781 | return; |
| 4782 | } |
| 4783 | |
| 4784 | /* But stop if we're attaching or setting up a remote |
| 4785 | connection. */ |
| 4786 | if (stop_soon == STOP_QUIETLY_NO_SIGSTOP |
| 4787 | || stop_soon == STOP_QUIETLY_REMOTE) |
| 4788 | { |
| 4789 | if (debug_infrun) |
| 4790 | fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n"); |
| 4791 | stop_waiting (ecs); |
| 4792 | return; |
| 4793 | } |
| 4794 | |
| 4795 | internal_error (__FILE__, __LINE__, |
| 4796 | _("unhandled stop_soon: %d"), (int) stop_soon); |
| 4797 | |
| 4798 | case TARGET_WAITKIND_SPURIOUS: |
| 4799 | if (debug_infrun) |
| 4800 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n"); |
| 4801 | if (!ptid_equal (ecs->ptid, inferior_ptid)) |
| 4802 | context_switch (ecs->ptid); |
| 4803 | resume (GDB_SIGNAL_0); |
| 4804 | prepare_to_wait (ecs); |
| 4805 | return; |
| 4806 | |
| 4807 | case TARGET_WAITKIND_EXITED: |
| 4808 | case TARGET_WAITKIND_SIGNALLED: |
| 4809 | if (debug_infrun) |
| 4810 | { |
| 4811 | if (ecs->ws.kind == TARGET_WAITKIND_EXITED) |
| 4812 | fprintf_unfiltered (gdb_stdlog, |
| 4813 | "infrun: TARGET_WAITKIND_EXITED\n"); |
| 4814 | else |
| 4815 | fprintf_unfiltered (gdb_stdlog, |
| 4816 | "infrun: TARGET_WAITKIND_SIGNALLED\n"); |
| 4817 | } |
| 4818 | |
| 4819 | inferior_ptid = ecs->ptid; |
| 4820 | set_current_inferior (find_inferior_ptid (ecs->ptid)); |
| 4821 | set_current_program_space (current_inferior ()->pspace); |
| 4822 | handle_vfork_child_exec_or_exit (0); |
| 4823 | target_terminal_ours (); /* Must do this before mourn anyway. */ |
| 4824 | |
| 4825 | /* Clearing any previous state of convenience variables. */ |
| 4826 | clear_exit_convenience_vars (); |
| 4827 | |
| 4828 | if (ecs->ws.kind == TARGET_WAITKIND_EXITED) |
| 4829 | { |
| 4830 | /* Record the exit code in the convenience variable $_exitcode, so |
| 4831 | that the user can inspect this again later. */ |
| 4832 | set_internalvar_integer (lookup_internalvar ("_exitcode"), |
| 4833 | (LONGEST) ecs->ws.value.integer); |
| 4834 | |
| 4835 | /* Also record this in the inferior itself. */ |
| 4836 | current_inferior ()->has_exit_code = 1; |
| 4837 | current_inferior ()->exit_code = (LONGEST) ecs->ws.value.integer; |
| 4838 | |
| 4839 | /* Support the --return-child-result option. */ |
| 4840 | return_child_result_value = ecs->ws.value.integer; |
| 4841 | |
| 4842 | observer_notify_exited (ecs->ws.value.integer); |
| 4843 | } |
| 4844 | else |
| 4845 | { |
| 4846 | struct regcache *regcache = get_thread_regcache (ecs->ptid); |
| 4847 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 4848 | |
| 4849 | if (gdbarch_gdb_signal_to_target_p (gdbarch)) |
| 4850 | { |
| 4851 | /* Set the value of the internal variable $_exitsignal, |
| 4852 | which holds the signal uncaught by the inferior. */ |
| 4853 | set_internalvar_integer (lookup_internalvar ("_exitsignal"), |
| 4854 | gdbarch_gdb_signal_to_target (gdbarch, |
| 4855 | ecs->ws.value.sig)); |
| 4856 | } |
| 4857 | else |
| 4858 | { |
| 4859 | /* We don't have access to the target's method used for |
| 4860 | converting between signal numbers (GDB's internal |
| 4861 | representation <-> target's representation). |
| 4862 | Therefore, we cannot do a good job at displaying this |
| 4863 | information to the user. It's better to just warn |
| 4864 | her about it (if infrun debugging is enabled), and |
| 4865 | give up. */ |
| 4866 | if (debug_infrun) |
| 4867 | fprintf_filtered (gdb_stdlog, _("\ |
| 4868 | Cannot fill $_exitsignal with the correct signal number.\n")); |
| 4869 | } |
| 4870 | |
| 4871 | observer_notify_signal_exited (ecs->ws.value.sig); |
| 4872 | } |
| 4873 | |
| 4874 | gdb_flush (gdb_stdout); |
| 4875 | target_mourn_inferior (); |
| 4876 | stop_print_frame = 0; |
| 4877 | stop_waiting (ecs); |
| 4878 | return; |
| 4879 | |
| 4880 | /* The following are the only cases in which we keep going; |
| 4881 | the above cases end in a continue or goto. */ |
| 4882 | case TARGET_WAITKIND_FORKED: |
| 4883 | case TARGET_WAITKIND_VFORKED: |
| 4884 | if (debug_infrun) |
| 4885 | { |
| 4886 | if (ecs->ws.kind == TARGET_WAITKIND_FORKED) |
| 4887 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n"); |
| 4888 | else |
| 4889 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_VFORKED\n"); |
| 4890 | } |
| 4891 | |
| 4892 | /* Check whether the inferior is displaced stepping. */ |
| 4893 | { |
| 4894 | struct regcache *regcache = get_thread_regcache (ecs->ptid); |
| 4895 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 4896 | struct displaced_step_inferior_state *displaced |
| 4897 | = get_displaced_stepping_state (ptid_get_pid (ecs->ptid)); |
| 4898 | |
| 4899 | /* If checking displaced stepping is supported, and thread |
| 4900 | ecs->ptid is displaced stepping. */ |
| 4901 | if (displaced && ptid_equal (displaced->step_ptid, ecs->ptid)) |
| 4902 | { |
| 4903 | struct inferior *parent_inf |
| 4904 | = find_inferior_ptid (ecs->ptid); |
| 4905 | struct regcache *child_regcache; |
| 4906 | CORE_ADDR parent_pc; |
| 4907 | |
| 4908 | /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED, |
| 4909 | indicating that the displaced stepping of syscall instruction |
| 4910 | has been done. Perform cleanup for parent process here. Note |
| 4911 | that this operation also cleans up the child process for vfork, |
| 4912 | because their pages are shared. */ |
| 4913 | displaced_step_fixup (ecs->ptid, GDB_SIGNAL_TRAP); |
| 4914 | /* Start a new step-over in another thread if there's one |
| 4915 | that needs it. */ |
| 4916 | start_step_over (); |
| 4917 | |
| 4918 | if (ecs->ws.kind == TARGET_WAITKIND_FORKED) |
| 4919 | { |
| 4920 | /* Restore scratch pad for child process. */ |
| 4921 | displaced_step_restore (displaced, ecs->ws.value.related_pid); |
| 4922 | } |
| 4923 | |
| 4924 | /* Since the vfork/fork syscall instruction was executed in the scratchpad, |
| 4925 | the child's PC is also within the scratchpad. Set the child's PC |
| 4926 | to the parent's PC value, which has already been fixed up. |
| 4927 | FIXME: we use the parent's aspace here, although we're touching |
| 4928 | the child, because the child hasn't been added to the inferior |
| 4929 | list yet at this point. */ |
| 4930 | |
| 4931 | child_regcache |
| 4932 | = get_thread_arch_aspace_regcache (ecs->ws.value.related_pid, |
| 4933 | gdbarch, |
| 4934 | parent_inf->aspace); |
| 4935 | /* Read PC value of parent process. */ |
| 4936 | parent_pc = regcache_read_pc (regcache); |
| 4937 | |
| 4938 | if (debug_displaced) |
| 4939 | fprintf_unfiltered (gdb_stdlog, |
| 4940 | "displaced: write child pc from %s to %s\n", |
| 4941 | paddress (gdbarch, |
| 4942 | regcache_read_pc (child_regcache)), |
| 4943 | paddress (gdbarch, parent_pc)); |
| 4944 | |
| 4945 | regcache_write_pc (child_regcache, parent_pc); |
| 4946 | } |
| 4947 | } |
| 4948 | |
| 4949 | if (!ptid_equal (ecs->ptid, inferior_ptid)) |
| 4950 | context_switch (ecs->ptid); |
| 4951 | |
| 4952 | /* Immediately detach breakpoints from the child before there's |
| 4953 | any chance of letting the user delete breakpoints from the |
| 4954 | breakpoint lists. If we don't do this early, it's easy to |
| 4955 | leave left over traps in the child, vis: "break foo; catch |
| 4956 | fork; c; <fork>; del; c; <child calls foo>". We only follow |
| 4957 | the fork on the last `continue', and by that time the |
| 4958 | breakpoint at "foo" is long gone from the breakpoint table. |
| 4959 | If we vforked, then we don't need to unpatch here, since both |
| 4960 | parent and child are sharing the same memory pages; we'll |
| 4961 | need to unpatch at follow/detach time instead to be certain |
| 4962 | that new breakpoints added between catchpoint hit time and |
| 4963 | vfork follow are detached. */ |
| 4964 | if (ecs->ws.kind != TARGET_WAITKIND_VFORKED) |
| 4965 | { |
| 4966 | /* This won't actually modify the breakpoint list, but will |
| 4967 | physically remove the breakpoints from the child. */ |
| 4968 | detach_breakpoints (ecs->ws.value.related_pid); |
| 4969 | } |
| 4970 | |
| 4971 | delete_just_stopped_threads_single_step_breakpoints (); |
| 4972 | |
| 4973 | /* In case the event is caught by a catchpoint, remember that |
| 4974 | the event is to be followed at the next resume of the thread, |
| 4975 | and not immediately. */ |
| 4976 | ecs->event_thread->pending_follow = ecs->ws; |
| 4977 | |
| 4978 | stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid)); |
| 4979 | |
| 4980 | ecs->event_thread->control.stop_bpstat |
| 4981 | = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()), |
| 4982 | stop_pc, ecs->ptid, &ecs->ws); |
| 4983 | |
| 4984 | /* If no catchpoint triggered for this, then keep going. Note |
| 4985 | that we're interested in knowing the bpstat actually causes a |
| 4986 | stop, not just if it may explain the signal. Software |
| 4987 | watchpoints, for example, always appear in the bpstat. */ |
| 4988 | if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat)) |
| 4989 | { |
| 4990 | ptid_t parent; |
| 4991 | ptid_t child; |
| 4992 | int should_resume; |
| 4993 | int follow_child |
| 4994 | = (follow_fork_mode_string == follow_fork_mode_child); |
| 4995 | |
| 4996 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 4997 | |
| 4998 | should_resume = follow_fork (); |
| 4999 | |
| 5000 | parent = ecs->ptid; |
| 5001 | child = ecs->ws.value.related_pid; |
| 5002 | |
| 5003 | /* In non-stop mode, also resume the other branch. */ |
| 5004 | if (!detach_fork && (non_stop |
| 5005 | || (sched_multi && target_is_non_stop_p ()))) |
| 5006 | { |
| 5007 | if (follow_child) |
| 5008 | switch_to_thread (parent); |
| 5009 | else |
| 5010 | switch_to_thread (child); |
| 5011 | |
| 5012 | ecs->event_thread = inferior_thread (); |
| 5013 | ecs->ptid = inferior_ptid; |
| 5014 | keep_going (ecs); |
| 5015 | } |
| 5016 | |
| 5017 | if (follow_child) |
| 5018 | switch_to_thread (child); |
| 5019 | else |
| 5020 | switch_to_thread (parent); |
| 5021 | |
| 5022 | ecs->event_thread = inferior_thread (); |
| 5023 | ecs->ptid = inferior_ptid; |
| 5024 | |
| 5025 | if (should_resume) |
| 5026 | keep_going (ecs); |
| 5027 | else |
| 5028 | stop_waiting (ecs); |
| 5029 | return; |
| 5030 | } |
| 5031 | process_event_stop_test (ecs); |
| 5032 | return; |
| 5033 | |
| 5034 | case TARGET_WAITKIND_VFORK_DONE: |
| 5035 | /* Done with the shared memory region. Re-insert breakpoints in |
| 5036 | the parent, and keep going. */ |
| 5037 | |
| 5038 | if (debug_infrun) |
| 5039 | fprintf_unfiltered (gdb_stdlog, |
| 5040 | "infrun: TARGET_WAITKIND_VFORK_DONE\n"); |
| 5041 | |
| 5042 | if (!ptid_equal (ecs->ptid, inferior_ptid)) |
| 5043 | context_switch (ecs->ptid); |
| 5044 | |
| 5045 | current_inferior ()->waiting_for_vfork_done = 0; |
| 5046 | current_inferior ()->pspace->breakpoints_not_allowed = 0; |
| 5047 | /* This also takes care of reinserting breakpoints in the |
| 5048 | previously locked inferior. */ |
| 5049 | keep_going (ecs); |
| 5050 | return; |
| 5051 | |
| 5052 | case TARGET_WAITKIND_EXECD: |
| 5053 | if (debug_infrun) |
| 5054 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n"); |
| 5055 | |
| 5056 | if (!ptid_equal (ecs->ptid, inferior_ptid)) |
| 5057 | context_switch (ecs->ptid); |
| 5058 | |
| 5059 | stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid)); |
| 5060 | |
| 5061 | /* Do whatever is necessary to the parent branch of the vfork. */ |
| 5062 | handle_vfork_child_exec_or_exit (1); |
| 5063 | |
| 5064 | /* This causes the eventpoints and symbol table to be reset. |
| 5065 | Must do this now, before trying to determine whether to |
| 5066 | stop. */ |
| 5067 | follow_exec (inferior_ptid, ecs->ws.value.execd_pathname); |
| 5068 | |
| 5069 | /* In follow_exec we may have deleted the original thread and |
| 5070 | created a new one. Make sure that the event thread is the |
| 5071 | execd thread for that case (this is a nop otherwise). */ |
| 5072 | ecs->event_thread = inferior_thread (); |
| 5073 | |
| 5074 | ecs->event_thread->control.stop_bpstat |
| 5075 | = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()), |
| 5076 | stop_pc, ecs->ptid, &ecs->ws); |
| 5077 | |
| 5078 | /* Note that this may be referenced from inside |
| 5079 | bpstat_stop_status above, through inferior_has_execd. */ |
| 5080 | xfree (ecs->ws.value.execd_pathname); |
| 5081 | ecs->ws.value.execd_pathname = NULL; |
| 5082 | |
| 5083 | /* If no catchpoint triggered for this, then keep going. */ |
| 5084 | if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat)) |
| 5085 | { |
| 5086 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 5087 | keep_going (ecs); |
| 5088 | return; |
| 5089 | } |
| 5090 | process_event_stop_test (ecs); |
| 5091 | return; |
| 5092 | |
| 5093 | /* Be careful not to try to gather much state about a thread |
| 5094 | that's in a syscall. It's frequently a losing proposition. */ |
| 5095 | case TARGET_WAITKIND_SYSCALL_ENTRY: |
| 5096 | if (debug_infrun) |
| 5097 | fprintf_unfiltered (gdb_stdlog, |
| 5098 | "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n"); |
| 5099 | /* Getting the current syscall number. */ |
| 5100 | if (handle_syscall_event (ecs) == 0) |
| 5101 | process_event_stop_test (ecs); |
| 5102 | return; |
| 5103 | |
| 5104 | /* Before examining the threads further, step this thread to |
| 5105 | get it entirely out of the syscall. (We get notice of the |
| 5106 | event when the thread is just on the verge of exiting a |
| 5107 | syscall. Stepping one instruction seems to get it back |
| 5108 | into user code.) */ |
| 5109 | case TARGET_WAITKIND_SYSCALL_RETURN: |
| 5110 | if (debug_infrun) |
| 5111 | fprintf_unfiltered (gdb_stdlog, |
| 5112 | "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n"); |
| 5113 | if (handle_syscall_event (ecs) == 0) |
| 5114 | process_event_stop_test (ecs); |
| 5115 | return; |
| 5116 | |
| 5117 | case TARGET_WAITKIND_STOPPED: |
| 5118 | if (debug_infrun) |
| 5119 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n"); |
| 5120 | ecs->event_thread->suspend.stop_signal = ecs->ws.value.sig; |
| 5121 | handle_signal_stop (ecs); |
| 5122 | return; |
| 5123 | |
| 5124 | case TARGET_WAITKIND_NO_HISTORY: |
| 5125 | if (debug_infrun) |
| 5126 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_HISTORY\n"); |
| 5127 | /* Reverse execution: target ran out of history info. */ |
| 5128 | |
| 5129 | /* Switch to the stopped thread. */ |
| 5130 | if (!ptid_equal (ecs->ptid, inferior_ptid)) |
| 5131 | context_switch (ecs->ptid); |
| 5132 | if (debug_infrun) |
| 5133 | fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n"); |
| 5134 | |
| 5135 | delete_just_stopped_threads_single_step_breakpoints (); |
| 5136 | stop_pc = regcache_read_pc (get_thread_regcache (inferior_ptid)); |
| 5137 | observer_notify_no_history (); |
| 5138 | stop_waiting (ecs); |
| 5139 | return; |
| 5140 | } |
| 5141 | } |
| 5142 | |
| 5143 | /* A wrapper around handle_inferior_event_1, which also makes sure |
| 5144 | that all temporary struct value objects that were created during |
| 5145 | the handling of the event get deleted at the end. */ |
| 5146 | |
| 5147 | static void |
| 5148 | handle_inferior_event (struct execution_control_state *ecs) |
| 5149 | { |
| 5150 | struct value *mark = value_mark (); |
| 5151 | |
| 5152 | handle_inferior_event_1 (ecs); |
| 5153 | /* Purge all temporary values created during the event handling, |
| 5154 | as it could be a long time before we return to the command level |
| 5155 | where such values would otherwise be purged. */ |
| 5156 | value_free_to_mark (mark); |
| 5157 | } |
| 5158 | |
| 5159 | /* Restart threads back to what they were trying to do back when we |
| 5160 | paused them for an in-line step-over. The EVENT_THREAD thread is |
| 5161 | ignored. */ |
| 5162 | |
| 5163 | static void |
| 5164 | restart_threads (struct thread_info *event_thread) |
| 5165 | { |
| 5166 | struct thread_info *tp; |
| 5167 | struct thread_info *step_over = NULL; |
| 5168 | |
| 5169 | /* In case the instruction just stepped spawned a new thread. */ |
| 5170 | update_thread_list (); |
| 5171 | |
| 5172 | ALL_NON_EXITED_THREADS (tp) |
| 5173 | { |
| 5174 | if (tp == event_thread) |
| 5175 | { |
| 5176 | if (debug_infrun) |
| 5177 | fprintf_unfiltered (gdb_stdlog, |
| 5178 | "infrun: restart threads: " |
| 5179 | "[%s] is event thread\n", |
| 5180 | target_pid_to_str (tp->ptid)); |
| 5181 | continue; |
| 5182 | } |
| 5183 | |
| 5184 | if (!(tp->state == THREAD_RUNNING || tp->control.in_infcall)) |
| 5185 | { |
| 5186 | if (debug_infrun) |
| 5187 | fprintf_unfiltered (gdb_stdlog, |
| 5188 | "infrun: restart threads: " |
| 5189 | "[%s] not meant to be running\n", |
| 5190 | target_pid_to_str (tp->ptid)); |
| 5191 | continue; |
| 5192 | } |
| 5193 | |
| 5194 | if (tp->resumed) |
| 5195 | { |
| 5196 | if (debug_infrun) |
| 5197 | fprintf_unfiltered (gdb_stdlog, |
| 5198 | "infrun: restart threads: [%s] resumed\n", |
| 5199 | target_pid_to_str (tp->ptid)); |
| 5200 | gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p); |
| 5201 | continue; |
| 5202 | } |
| 5203 | |
| 5204 | if (thread_is_in_step_over_chain (tp)) |
| 5205 | { |
| 5206 | if (debug_infrun) |
| 5207 | fprintf_unfiltered (gdb_stdlog, |
| 5208 | "infrun: restart threads: " |
| 5209 | "[%s] needs step-over\n", |
| 5210 | target_pid_to_str (tp->ptid)); |
| 5211 | gdb_assert (!tp->resumed); |
| 5212 | continue; |
| 5213 | } |
| 5214 | |
| 5215 | |
| 5216 | if (tp->suspend.waitstatus_pending_p) |
| 5217 | { |
| 5218 | if (debug_infrun) |
| 5219 | fprintf_unfiltered (gdb_stdlog, |
| 5220 | "infrun: restart threads: " |
| 5221 | "[%s] has pending status\n", |
| 5222 | target_pid_to_str (tp->ptid)); |
| 5223 | tp->resumed = 1; |
| 5224 | continue; |
| 5225 | } |
| 5226 | |
| 5227 | /* If some thread needs to start a step-over at this point, it |
| 5228 | should still be in the step-over queue, and thus skipped |
| 5229 | above. */ |
| 5230 | if (thread_still_needs_step_over (tp)) |
| 5231 | { |
| 5232 | internal_error (__FILE__, __LINE__, |
| 5233 | "thread [%s] needs a step-over, but not in " |
| 5234 | "step-over queue\n", |
| 5235 | target_pid_to_str (tp->ptid)); |
| 5236 | } |
| 5237 | |
| 5238 | if (currently_stepping (tp)) |
| 5239 | { |
| 5240 | if (debug_infrun) |
| 5241 | fprintf_unfiltered (gdb_stdlog, |
| 5242 | "infrun: restart threads: [%s] was stepping\n", |
| 5243 | target_pid_to_str (tp->ptid)); |
| 5244 | keep_going_stepped_thread (tp); |
| 5245 | } |
| 5246 | else |
| 5247 | { |
| 5248 | struct execution_control_state ecss; |
| 5249 | struct execution_control_state *ecs = &ecss; |
| 5250 | |
| 5251 | if (debug_infrun) |
| 5252 | fprintf_unfiltered (gdb_stdlog, |
| 5253 | "infrun: restart threads: [%s] continuing\n", |
| 5254 | target_pid_to_str (tp->ptid)); |
| 5255 | reset_ecs (ecs, tp); |
| 5256 | switch_to_thread (tp->ptid); |
| 5257 | keep_going_pass_signal (ecs); |
| 5258 | } |
| 5259 | } |
| 5260 | } |
| 5261 | |
| 5262 | /* Callback for iterate_over_threads. Find a resumed thread that has |
| 5263 | a pending waitstatus. */ |
| 5264 | |
| 5265 | static int |
| 5266 | resumed_thread_with_pending_status (struct thread_info *tp, |
| 5267 | void *arg) |
| 5268 | { |
| 5269 | return (tp->resumed |
| 5270 | && tp->suspend.waitstatus_pending_p); |
| 5271 | } |
| 5272 | |
| 5273 | /* Called when we get an event that may finish an in-line or |
| 5274 | out-of-line (displaced stepping) step-over started previously. |
| 5275 | Return true if the event is processed and we should go back to the |
| 5276 | event loop; false if the caller should continue processing the |
| 5277 | event. */ |
| 5278 | |
| 5279 | static int |
| 5280 | finish_step_over (struct execution_control_state *ecs) |
| 5281 | { |
| 5282 | int had_step_over_info; |
| 5283 | |
| 5284 | displaced_step_fixup (ecs->ptid, |
| 5285 | ecs->event_thread->suspend.stop_signal); |
| 5286 | |
| 5287 | had_step_over_info = step_over_info_valid_p (); |
| 5288 | |
| 5289 | if (had_step_over_info) |
| 5290 | { |
| 5291 | /* If we're stepping over a breakpoint with all threads locked, |
| 5292 | then only the thread that was stepped should be reporting |
| 5293 | back an event. */ |
| 5294 | gdb_assert (ecs->event_thread->control.trap_expected); |
| 5295 | |
| 5296 | if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP) |
| 5297 | clear_step_over_info (); |
| 5298 | } |
| 5299 | |
| 5300 | if (!target_is_non_stop_p ()) |
| 5301 | return 0; |
| 5302 | |
| 5303 | /* Start a new step-over in another thread if there's one that |
| 5304 | needs it. */ |
| 5305 | start_step_over (); |
| 5306 | |
| 5307 | /* If we were stepping over a breakpoint before, and haven't started |
| 5308 | a new in-line step-over sequence, then restart all other threads |
| 5309 | (except the event thread). We can't do this in all-stop, as then |
| 5310 | e.g., we wouldn't be able to issue any other remote packet until |
| 5311 | these other threads stop. */ |
| 5312 | if (had_step_over_info && !step_over_info_valid_p ()) |
| 5313 | { |
| 5314 | struct thread_info *pending; |
| 5315 | |
| 5316 | /* If we only have threads with pending statuses, the restart |
| 5317 | below won't restart any thread and so nothing re-inserts the |
| 5318 | breakpoint we just stepped over. But we need it inserted |
| 5319 | when we later process the pending events, otherwise if |
| 5320 | another thread has a pending event for this breakpoint too, |
| 5321 | we'd discard its event (because the breakpoint that |
| 5322 | originally caused the event was no longer inserted). */ |
| 5323 | context_switch (ecs->ptid); |
| 5324 | insert_breakpoints (); |
| 5325 | |
| 5326 | restart_threads (ecs->event_thread); |
| 5327 | |
| 5328 | /* If we have events pending, go through handle_inferior_event |
| 5329 | again, picking up a pending event at random. This avoids |
| 5330 | thread starvation. */ |
| 5331 | |
| 5332 | /* But not if we just stepped over a watchpoint in order to let |
| 5333 | the instruction execute so we can evaluate its expression. |
| 5334 | The set of watchpoints that triggered is recorded in the |
| 5335 | breakpoint objects themselves (see bp->watchpoint_triggered). |
| 5336 | If we processed another event first, that other event could |
| 5337 | clobber this info. */ |
| 5338 | if (ecs->event_thread->stepping_over_watchpoint) |
| 5339 | return 0; |
| 5340 | |
| 5341 | pending = iterate_over_threads (resumed_thread_with_pending_status, |
| 5342 | NULL); |
| 5343 | if (pending != NULL) |
| 5344 | { |
| 5345 | struct thread_info *tp = ecs->event_thread; |
| 5346 | struct regcache *regcache; |
| 5347 | |
| 5348 | if (debug_infrun) |
| 5349 | { |
| 5350 | fprintf_unfiltered (gdb_stdlog, |
| 5351 | "infrun: found resumed threads with " |
| 5352 | "pending events, saving status\n"); |
| 5353 | } |
| 5354 | |
| 5355 | gdb_assert (pending != tp); |
| 5356 | |
| 5357 | /* Record the event thread's event for later. */ |
| 5358 | save_waitstatus (tp, &ecs->ws); |
| 5359 | /* This was cleared early, by handle_inferior_event. Set it |
| 5360 | so this pending event is considered by |
| 5361 | do_target_wait. */ |
| 5362 | tp->resumed = 1; |
| 5363 | |
| 5364 | gdb_assert (!tp->executing); |
| 5365 | |
| 5366 | regcache = get_thread_regcache (tp->ptid); |
| 5367 | tp->suspend.stop_pc = regcache_read_pc (regcache); |
| 5368 | |
| 5369 | if (debug_infrun) |
| 5370 | { |
| 5371 | fprintf_unfiltered (gdb_stdlog, |
| 5372 | "infrun: saved stop_pc=%s for %s " |
| 5373 | "(currently_stepping=%d)\n", |
| 5374 | paddress (target_gdbarch (), |
| 5375 | tp->suspend.stop_pc), |
| 5376 | target_pid_to_str (tp->ptid), |
| 5377 | currently_stepping (tp)); |
| 5378 | } |
| 5379 | |
| 5380 | /* This in-line step-over finished; clear this so we won't |
| 5381 | start a new one. This is what handle_signal_stop would |
| 5382 | do, if we returned false. */ |
| 5383 | tp->stepping_over_breakpoint = 0; |
| 5384 | |
| 5385 | /* Wake up the event loop again. */ |
| 5386 | mark_async_event_handler (infrun_async_inferior_event_token); |
| 5387 | |
| 5388 | prepare_to_wait (ecs); |
| 5389 | return 1; |
| 5390 | } |
| 5391 | } |
| 5392 | |
| 5393 | return 0; |
| 5394 | } |
| 5395 | |
| 5396 | /* Come here when the program has stopped with a signal. */ |
| 5397 | |
| 5398 | static void |
| 5399 | handle_signal_stop (struct execution_control_state *ecs) |
| 5400 | { |
| 5401 | struct frame_info *frame; |
| 5402 | struct gdbarch *gdbarch; |
| 5403 | int stopped_by_watchpoint; |
| 5404 | enum stop_kind stop_soon; |
| 5405 | int random_signal; |
| 5406 | |
| 5407 | gdb_assert (ecs->ws.kind == TARGET_WAITKIND_STOPPED); |
| 5408 | |
| 5409 | /* Do we need to clean up the state of a thread that has |
| 5410 | completed a displaced single-step? (Doing so usually affects |
| 5411 | the PC, so do it here, before we set stop_pc.) */ |
| 5412 | if (finish_step_over (ecs)) |
| 5413 | return; |
| 5414 | |
| 5415 | /* If we either finished a single-step or hit a breakpoint, but |
| 5416 | the user wanted this thread to be stopped, pretend we got a |
| 5417 | SIG0 (generic unsignaled stop). */ |
| 5418 | if (ecs->event_thread->stop_requested |
| 5419 | && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP) |
| 5420 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 5421 | |
| 5422 | stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid)); |
| 5423 | |
| 5424 | if (debug_infrun) |
| 5425 | { |
| 5426 | struct regcache *regcache = get_thread_regcache (ecs->ptid); |
| 5427 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 5428 | struct cleanup *old_chain = save_inferior_ptid (); |
| 5429 | |
| 5430 | inferior_ptid = ecs->ptid; |
| 5431 | |
| 5432 | fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = %s\n", |
| 5433 | paddress (gdbarch, stop_pc)); |
| 5434 | if (target_stopped_by_watchpoint ()) |
| 5435 | { |
| 5436 | CORE_ADDR addr; |
| 5437 | |
| 5438 | fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n"); |
| 5439 | |
| 5440 | if (target_stopped_data_address (¤t_target, &addr)) |
| 5441 | fprintf_unfiltered (gdb_stdlog, |
| 5442 | "infrun: stopped data address = %s\n", |
| 5443 | paddress (gdbarch, addr)); |
| 5444 | else |
| 5445 | fprintf_unfiltered (gdb_stdlog, |
| 5446 | "infrun: (no data address available)\n"); |
| 5447 | } |
| 5448 | |
| 5449 | do_cleanups (old_chain); |
| 5450 | } |
| 5451 | |
| 5452 | /* This is originated from start_remote(), start_inferior() and |
| 5453 | shared libraries hook functions. */ |
| 5454 | stop_soon = get_inferior_stop_soon (ecs->ptid); |
| 5455 | if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE) |
| 5456 | { |
| 5457 | if (!ptid_equal (ecs->ptid, inferior_ptid)) |
| 5458 | context_switch (ecs->ptid); |
| 5459 | if (debug_infrun) |
| 5460 | fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n"); |
| 5461 | stop_print_frame = 1; |
| 5462 | stop_waiting (ecs); |
| 5463 | return; |
| 5464 | } |
| 5465 | |
| 5466 | if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP |
| 5467 | && stop_after_trap) |
| 5468 | { |
| 5469 | if (!ptid_equal (ecs->ptid, inferior_ptid)) |
| 5470 | context_switch (ecs->ptid); |
| 5471 | if (debug_infrun) |
| 5472 | fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n"); |
| 5473 | stop_print_frame = 0; |
| 5474 | stop_waiting (ecs); |
| 5475 | return; |
| 5476 | } |
| 5477 | |
| 5478 | /* This originates from attach_command(). We need to overwrite |
| 5479 | the stop_signal here, because some kernels don't ignore a |
| 5480 | SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call. |
| 5481 | See more comments in inferior.h. On the other hand, if we |
| 5482 | get a non-SIGSTOP, report it to the user - assume the backend |
| 5483 | will handle the SIGSTOP if it should show up later. |
| 5484 | |
| 5485 | Also consider that the attach is complete when we see a |
| 5486 | SIGTRAP. Some systems (e.g. Windows), and stubs supporting |
| 5487 | target extended-remote report it instead of a SIGSTOP |
| 5488 | (e.g. gdbserver). We already rely on SIGTRAP being our |
| 5489 | signal, so this is no exception. |
| 5490 | |
| 5491 | Also consider that the attach is complete when we see a |
| 5492 | GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell |
| 5493 | the target to stop all threads of the inferior, in case the |
| 5494 | low level attach operation doesn't stop them implicitly. If |
| 5495 | they weren't stopped implicitly, then the stub will report a |
| 5496 | GDB_SIGNAL_0, meaning: stopped for no particular reason |
| 5497 | other than GDB's request. */ |
| 5498 | if (stop_soon == STOP_QUIETLY_NO_SIGSTOP |
| 5499 | && (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_STOP |
| 5500 | || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP |
| 5501 | || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_0)) |
| 5502 | { |
| 5503 | stop_print_frame = 1; |
| 5504 | stop_waiting (ecs); |
| 5505 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 5506 | return; |
| 5507 | } |
| 5508 | |
| 5509 | /* See if something interesting happened to the non-current thread. If |
| 5510 | so, then switch to that thread. */ |
| 5511 | if (!ptid_equal (ecs->ptid, inferior_ptid)) |
| 5512 | { |
| 5513 | if (debug_infrun) |
| 5514 | fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n"); |
| 5515 | |
| 5516 | context_switch (ecs->ptid); |
| 5517 | |
| 5518 | if (deprecated_context_hook) |
| 5519 | deprecated_context_hook (pid_to_thread_id (ecs->ptid)); |
| 5520 | } |
| 5521 | |
| 5522 | /* At this point, get hold of the now-current thread's frame. */ |
| 5523 | frame = get_current_frame (); |
| 5524 | gdbarch = get_frame_arch (frame); |
| 5525 | |
| 5526 | /* Pull the single step breakpoints out of the target. */ |
| 5527 | if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP) |
| 5528 | { |
| 5529 | struct regcache *regcache; |
| 5530 | struct address_space *aspace; |
| 5531 | CORE_ADDR pc; |
| 5532 | |
| 5533 | regcache = get_thread_regcache (ecs->ptid); |
| 5534 | aspace = get_regcache_aspace (regcache); |
| 5535 | pc = regcache_read_pc (regcache); |
| 5536 | |
| 5537 | /* However, before doing so, if this single-step breakpoint was |
| 5538 | actually for another thread, set this thread up for moving |
| 5539 | past it. */ |
| 5540 | if (!thread_has_single_step_breakpoint_here (ecs->event_thread, |
| 5541 | aspace, pc)) |
| 5542 | { |
| 5543 | if (single_step_breakpoint_inserted_here_p (aspace, pc)) |
| 5544 | { |
| 5545 | if (debug_infrun) |
| 5546 | { |
| 5547 | fprintf_unfiltered (gdb_stdlog, |
| 5548 | "infrun: [%s] hit another thread's " |
| 5549 | "single-step breakpoint\n", |
| 5550 | target_pid_to_str (ecs->ptid)); |
| 5551 | } |
| 5552 | ecs->hit_singlestep_breakpoint = 1; |
| 5553 | } |
| 5554 | } |
| 5555 | else |
| 5556 | { |
| 5557 | if (debug_infrun) |
| 5558 | { |
| 5559 | fprintf_unfiltered (gdb_stdlog, |
| 5560 | "infrun: [%s] hit its " |
| 5561 | "single-step breakpoint\n", |
| 5562 | target_pid_to_str (ecs->ptid)); |
| 5563 | } |
| 5564 | } |
| 5565 | } |
| 5566 | delete_just_stopped_threads_single_step_breakpoints (); |
| 5567 | |
| 5568 | if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP |
| 5569 | && ecs->event_thread->control.trap_expected |
| 5570 | && ecs->event_thread->stepping_over_watchpoint) |
| 5571 | stopped_by_watchpoint = 0; |
| 5572 | else |
| 5573 | stopped_by_watchpoint = watchpoints_triggered (&ecs->ws); |
| 5574 | |
| 5575 | /* If necessary, step over this watchpoint. We'll be back to display |
| 5576 | it in a moment. */ |
| 5577 | if (stopped_by_watchpoint |
| 5578 | && (target_have_steppable_watchpoint |
| 5579 | || gdbarch_have_nonsteppable_watchpoint (gdbarch))) |
| 5580 | { |
| 5581 | /* At this point, we are stopped at an instruction which has |
| 5582 | attempted to write to a piece of memory under control of |
| 5583 | a watchpoint. The instruction hasn't actually executed |
| 5584 | yet. If we were to evaluate the watchpoint expression |
| 5585 | now, we would get the old value, and therefore no change |
| 5586 | would seem to have occurred. |
| 5587 | |
| 5588 | In order to make watchpoints work `right', we really need |
| 5589 | to complete the memory write, and then evaluate the |
| 5590 | watchpoint expression. We do this by single-stepping the |
| 5591 | target. |
| 5592 | |
| 5593 | It may not be necessary to disable the watchpoint to step over |
| 5594 | it. For example, the PA can (with some kernel cooperation) |
| 5595 | single step over a watchpoint without disabling the watchpoint. |
| 5596 | |
| 5597 | It is far more common to need to disable a watchpoint to step |
| 5598 | the inferior over it. If we have non-steppable watchpoints, |
| 5599 | we must disable the current watchpoint; it's simplest to |
| 5600 | disable all watchpoints. |
| 5601 | |
| 5602 | Any breakpoint at PC must also be stepped over -- if there's |
| 5603 | one, it will have already triggered before the watchpoint |
| 5604 | triggered, and we either already reported it to the user, or |
| 5605 | it didn't cause a stop and we called keep_going. In either |
| 5606 | case, if there was a breakpoint at PC, we must be trying to |
| 5607 | step past it. */ |
| 5608 | ecs->event_thread->stepping_over_watchpoint = 1; |
| 5609 | keep_going (ecs); |
| 5610 | return; |
| 5611 | } |
| 5612 | |
| 5613 | ecs->event_thread->stepping_over_breakpoint = 0; |
| 5614 | ecs->event_thread->stepping_over_watchpoint = 0; |
| 5615 | bpstat_clear (&ecs->event_thread->control.stop_bpstat); |
| 5616 | ecs->event_thread->control.stop_step = 0; |
| 5617 | stop_print_frame = 1; |
| 5618 | stopped_by_random_signal = 0; |
| 5619 | |
| 5620 | /* Hide inlined functions starting here, unless we just performed stepi or |
| 5621 | nexti. After stepi and nexti, always show the innermost frame (not any |
| 5622 | inline function call sites). */ |
| 5623 | if (ecs->event_thread->control.step_range_end != 1) |
| 5624 | { |
| 5625 | struct address_space *aspace = |
| 5626 | get_regcache_aspace (get_thread_regcache (ecs->ptid)); |
| 5627 | |
| 5628 | /* skip_inline_frames is expensive, so we avoid it if we can |
| 5629 | determine that the address is one where functions cannot have |
| 5630 | been inlined. This improves performance with inferiors that |
| 5631 | load a lot of shared libraries, because the solib event |
| 5632 | breakpoint is defined as the address of a function (i.e. not |
| 5633 | inline). Note that we have to check the previous PC as well |
| 5634 | as the current one to catch cases when we have just |
| 5635 | single-stepped off a breakpoint prior to reinstating it. |
| 5636 | Note that we're assuming that the code we single-step to is |
| 5637 | not inline, but that's not definitive: there's nothing |
| 5638 | preventing the event breakpoint function from containing |
| 5639 | inlined code, and the single-step ending up there. If the |
| 5640 | user had set a breakpoint on that inlined code, the missing |
| 5641 | skip_inline_frames call would break things. Fortunately |
| 5642 | that's an extremely unlikely scenario. */ |
| 5643 | if (!pc_at_non_inline_function (aspace, stop_pc, &ecs->ws) |
| 5644 | && !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP |
| 5645 | && ecs->event_thread->control.trap_expected |
| 5646 | && pc_at_non_inline_function (aspace, |
| 5647 | ecs->event_thread->prev_pc, |
| 5648 | &ecs->ws))) |
| 5649 | { |
| 5650 | skip_inline_frames (ecs->ptid); |
| 5651 | |
| 5652 | /* Re-fetch current thread's frame in case that invalidated |
| 5653 | the frame cache. */ |
| 5654 | frame = get_current_frame (); |
| 5655 | gdbarch = get_frame_arch (frame); |
| 5656 | } |
| 5657 | } |
| 5658 | |
| 5659 | if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP |
| 5660 | && ecs->event_thread->control.trap_expected |
| 5661 | && gdbarch_single_step_through_delay_p (gdbarch) |
| 5662 | && currently_stepping (ecs->event_thread)) |
| 5663 | { |
| 5664 | /* We're trying to step off a breakpoint. Turns out that we're |
| 5665 | also on an instruction that needs to be stepped multiple |
| 5666 | times before it's been fully executing. E.g., architectures |
| 5667 | with a delay slot. It needs to be stepped twice, once for |
| 5668 | the instruction and once for the delay slot. */ |
| 5669 | int step_through_delay |
| 5670 | = gdbarch_single_step_through_delay (gdbarch, frame); |
| 5671 | |
| 5672 | if (debug_infrun && step_through_delay) |
| 5673 | fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n"); |
| 5674 | if (ecs->event_thread->control.step_range_end == 0 |
| 5675 | && step_through_delay) |
| 5676 | { |
| 5677 | /* The user issued a continue when stopped at a breakpoint. |
| 5678 | Set up for another trap and get out of here. */ |
| 5679 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 5680 | keep_going (ecs); |
| 5681 | return; |
| 5682 | } |
| 5683 | else if (step_through_delay) |
| 5684 | { |
| 5685 | /* The user issued a step when stopped at a breakpoint. |
| 5686 | Maybe we should stop, maybe we should not - the delay |
| 5687 | slot *might* correspond to a line of source. In any |
| 5688 | case, don't decide that here, just set |
| 5689 | ecs->stepping_over_breakpoint, making sure we |
| 5690 | single-step again before breakpoints are re-inserted. */ |
| 5691 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 5692 | } |
| 5693 | } |
| 5694 | |
| 5695 | /* See if there is a breakpoint/watchpoint/catchpoint/etc. that |
| 5696 | handles this event. */ |
| 5697 | ecs->event_thread->control.stop_bpstat |
| 5698 | = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()), |
| 5699 | stop_pc, ecs->ptid, &ecs->ws); |
| 5700 | |
| 5701 | /* Following in case break condition called a |
| 5702 | function. */ |
| 5703 | stop_print_frame = 1; |
| 5704 | |
| 5705 | /* This is where we handle "moribund" watchpoints. Unlike |
| 5706 | software breakpoints traps, hardware watchpoint traps are |
| 5707 | always distinguishable from random traps. If no high-level |
| 5708 | watchpoint is associated with the reported stop data address |
| 5709 | anymore, then the bpstat does not explain the signal --- |
| 5710 | simply make sure to ignore it if `stopped_by_watchpoint' is |
| 5711 | set. */ |
| 5712 | |
| 5713 | if (debug_infrun |
| 5714 | && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP |
| 5715 | && !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat, |
| 5716 | GDB_SIGNAL_TRAP) |
| 5717 | && stopped_by_watchpoint) |
| 5718 | fprintf_unfiltered (gdb_stdlog, |
| 5719 | "infrun: no user watchpoint explains " |
| 5720 | "watchpoint SIGTRAP, ignoring\n"); |
| 5721 | |
| 5722 | /* NOTE: cagney/2003-03-29: These checks for a random signal |
| 5723 | at one stage in the past included checks for an inferior |
| 5724 | function call's call dummy's return breakpoint. The original |
| 5725 | comment, that went with the test, read: |
| 5726 | |
| 5727 | ``End of a stack dummy. Some systems (e.g. Sony news) give |
| 5728 | another signal besides SIGTRAP, so check here as well as |
| 5729 | above.'' |
| 5730 | |
| 5731 | If someone ever tries to get call dummys on a |
| 5732 | non-executable stack to work (where the target would stop |
| 5733 | with something like a SIGSEGV), then those tests might need |
| 5734 | to be re-instated. Given, however, that the tests were only |
| 5735 | enabled when momentary breakpoints were not being used, I |
| 5736 | suspect that it won't be the case. |
| 5737 | |
| 5738 | NOTE: kettenis/2004-02-05: Indeed such checks don't seem to |
| 5739 | be necessary for call dummies on a non-executable stack on |
| 5740 | SPARC. */ |
| 5741 | |
| 5742 | /* See if the breakpoints module can explain the signal. */ |
| 5743 | random_signal |
| 5744 | = !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat, |
| 5745 | ecs->event_thread->suspend.stop_signal); |
| 5746 | |
| 5747 | /* Maybe this was a trap for a software breakpoint that has since |
| 5748 | been removed. */ |
| 5749 | if (random_signal && target_stopped_by_sw_breakpoint ()) |
| 5750 | { |
| 5751 | if (program_breakpoint_here_p (gdbarch, stop_pc)) |
| 5752 | { |
| 5753 | struct regcache *regcache; |
| 5754 | int decr_pc; |
| 5755 | |
| 5756 | /* Re-adjust PC to what the program would see if GDB was not |
| 5757 | debugging it. */ |
| 5758 | regcache = get_thread_regcache (ecs->event_thread->ptid); |
| 5759 | decr_pc = gdbarch_decr_pc_after_break (gdbarch); |
| 5760 | if (decr_pc != 0) |
| 5761 | { |
| 5762 | struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL); |
| 5763 | |
| 5764 | if (record_full_is_used ()) |
| 5765 | record_full_gdb_operation_disable_set (); |
| 5766 | |
| 5767 | regcache_write_pc (regcache, stop_pc + decr_pc); |
| 5768 | |
| 5769 | do_cleanups (old_cleanups); |
| 5770 | } |
| 5771 | } |
| 5772 | else |
| 5773 | { |
| 5774 | /* A delayed software breakpoint event. Ignore the trap. */ |
| 5775 | if (debug_infrun) |
| 5776 | fprintf_unfiltered (gdb_stdlog, |
| 5777 | "infrun: delayed software breakpoint " |
| 5778 | "trap, ignoring\n"); |
| 5779 | random_signal = 0; |
| 5780 | } |
| 5781 | } |
| 5782 | |
| 5783 | /* Maybe this was a trap for a hardware breakpoint/watchpoint that |
| 5784 | has since been removed. */ |
| 5785 | if (random_signal && target_stopped_by_hw_breakpoint ()) |
| 5786 | { |
| 5787 | /* A delayed hardware breakpoint event. Ignore the trap. */ |
| 5788 | if (debug_infrun) |
| 5789 | fprintf_unfiltered (gdb_stdlog, |
| 5790 | "infrun: delayed hardware breakpoint/watchpoint " |
| 5791 | "trap, ignoring\n"); |
| 5792 | random_signal = 0; |
| 5793 | } |
| 5794 | |
| 5795 | /* If not, perhaps stepping/nexting can. */ |
| 5796 | if (random_signal) |
| 5797 | random_signal = !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP |
| 5798 | && currently_stepping (ecs->event_thread)); |
| 5799 | |
| 5800 | /* Perhaps the thread hit a single-step breakpoint of _another_ |
| 5801 | thread. Single-step breakpoints are transparent to the |
| 5802 | breakpoints module. */ |
| 5803 | if (random_signal) |
| 5804 | random_signal = !ecs->hit_singlestep_breakpoint; |
| 5805 | |
| 5806 | /* No? Perhaps we got a moribund watchpoint. */ |
| 5807 | if (random_signal) |
| 5808 | random_signal = !stopped_by_watchpoint; |
| 5809 | |
| 5810 | /* For the program's own signals, act according to |
| 5811 | the signal handling tables. */ |
| 5812 | |
| 5813 | if (random_signal) |
| 5814 | { |
| 5815 | /* Signal not for debugging purposes. */ |
| 5816 | struct inferior *inf = find_inferior_ptid (ecs->ptid); |
| 5817 | enum gdb_signal stop_signal = ecs->event_thread->suspend.stop_signal; |
| 5818 | |
| 5819 | if (debug_infrun) |
| 5820 | fprintf_unfiltered (gdb_stdlog, "infrun: random signal (%s)\n", |
| 5821 | gdb_signal_to_symbol_string (stop_signal)); |
| 5822 | |
| 5823 | stopped_by_random_signal = 1; |
| 5824 | |
| 5825 | /* Always stop on signals if we're either just gaining control |
| 5826 | of the program, or the user explicitly requested this thread |
| 5827 | to remain stopped. */ |
| 5828 | if (stop_soon != NO_STOP_QUIETLY |
| 5829 | || ecs->event_thread->stop_requested |
| 5830 | || (!inf->detaching |
| 5831 | && signal_stop_state (ecs->event_thread->suspend.stop_signal))) |
| 5832 | { |
| 5833 | stop_waiting (ecs); |
| 5834 | return; |
| 5835 | } |
| 5836 | |
| 5837 | /* Notify observers the signal has "handle print" set. Note we |
| 5838 | returned early above if stopping; normal_stop handles the |
| 5839 | printing in that case. */ |
| 5840 | if (signal_print[ecs->event_thread->suspend.stop_signal]) |
| 5841 | { |
| 5842 | /* The signal table tells us to print about this signal. */ |
| 5843 | target_terminal_ours_for_output (); |
| 5844 | observer_notify_signal_received (ecs->event_thread->suspend.stop_signal); |
| 5845 | target_terminal_inferior (); |
| 5846 | } |
| 5847 | |
| 5848 | /* Clear the signal if it should not be passed. */ |
| 5849 | if (signal_program[ecs->event_thread->suspend.stop_signal] == 0) |
| 5850 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 5851 | |
| 5852 | if (ecs->event_thread->prev_pc == stop_pc |
| 5853 | && ecs->event_thread->control.trap_expected |
| 5854 | && ecs->event_thread->control.step_resume_breakpoint == NULL) |
| 5855 | { |
| 5856 | int was_in_line; |
| 5857 | |
| 5858 | /* We were just starting a new sequence, attempting to |
| 5859 | single-step off of a breakpoint and expecting a SIGTRAP. |
| 5860 | Instead this signal arrives. This signal will take us out |
| 5861 | of the stepping range so GDB needs to remember to, when |
| 5862 | the signal handler returns, resume stepping off that |
| 5863 | breakpoint. */ |
| 5864 | /* To simplify things, "continue" is forced to use the same |
| 5865 | code paths as single-step - set a breakpoint at the |
| 5866 | signal return address and then, once hit, step off that |
| 5867 | breakpoint. */ |
| 5868 | if (debug_infrun) |
| 5869 | fprintf_unfiltered (gdb_stdlog, |
| 5870 | "infrun: signal arrived while stepping over " |
| 5871 | "breakpoint\n"); |
| 5872 | |
| 5873 | was_in_line = step_over_info_valid_p (); |
| 5874 | clear_step_over_info (); |
| 5875 | insert_hp_step_resume_breakpoint_at_frame (frame); |
| 5876 | ecs->event_thread->step_after_step_resume_breakpoint = 1; |
| 5877 | /* Reset trap_expected to ensure breakpoints are re-inserted. */ |
| 5878 | ecs->event_thread->control.trap_expected = 0; |
| 5879 | |
| 5880 | if (target_is_non_stop_p ()) |
| 5881 | { |
| 5882 | /* Either "set non-stop" is "on", or the target is |
| 5883 | always in non-stop mode. In this case, we have a bit |
| 5884 | more work to do. Resume the current thread, and if |
| 5885 | we had paused all threads, restart them while the |
| 5886 | signal handler runs. */ |
| 5887 | keep_going (ecs); |
| 5888 | |
| 5889 | if (was_in_line) |
| 5890 | { |
| 5891 | restart_threads (ecs->event_thread); |
| 5892 | } |
| 5893 | else if (debug_infrun) |
| 5894 | { |
| 5895 | fprintf_unfiltered (gdb_stdlog, |
| 5896 | "infrun: no need to restart threads\n"); |
| 5897 | } |
| 5898 | return; |
| 5899 | } |
| 5900 | |
| 5901 | /* If we were nexting/stepping some other thread, switch to |
| 5902 | it, so that we don't continue it, losing control. */ |
| 5903 | if (!switch_back_to_stepped_thread (ecs)) |
| 5904 | keep_going (ecs); |
| 5905 | return; |
| 5906 | } |
| 5907 | |
| 5908 | if (ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_0 |
| 5909 | && (pc_in_thread_step_range (stop_pc, ecs->event_thread) |
| 5910 | || ecs->event_thread->control.step_range_end == 1) |
| 5911 | && frame_id_eq (get_stack_frame_id (frame), |
| 5912 | ecs->event_thread->control.step_stack_frame_id) |
| 5913 | && ecs->event_thread->control.step_resume_breakpoint == NULL) |
| 5914 | { |
| 5915 | /* The inferior is about to take a signal that will take it |
| 5916 | out of the single step range. Set a breakpoint at the |
| 5917 | current PC (which is presumably where the signal handler |
| 5918 | will eventually return) and then allow the inferior to |
| 5919 | run free. |
| 5920 | |
| 5921 | Note that this is only needed for a signal delivered |
| 5922 | while in the single-step range. Nested signals aren't a |
| 5923 | problem as they eventually all return. */ |
| 5924 | if (debug_infrun) |
| 5925 | fprintf_unfiltered (gdb_stdlog, |
| 5926 | "infrun: signal may take us out of " |
| 5927 | "single-step range\n"); |
| 5928 | |
| 5929 | clear_step_over_info (); |
| 5930 | insert_hp_step_resume_breakpoint_at_frame (frame); |
| 5931 | ecs->event_thread->step_after_step_resume_breakpoint = 1; |
| 5932 | /* Reset trap_expected to ensure breakpoints are re-inserted. */ |
| 5933 | ecs->event_thread->control.trap_expected = 0; |
| 5934 | keep_going (ecs); |
| 5935 | return; |
| 5936 | } |
| 5937 | |
| 5938 | /* Note: step_resume_breakpoint may be non-NULL. This occures |
| 5939 | when either there's a nested signal, or when there's a |
| 5940 | pending signal enabled just as the signal handler returns |
| 5941 | (leaving the inferior at the step-resume-breakpoint without |
| 5942 | actually executing it). Either way continue until the |
| 5943 | breakpoint is really hit. */ |
| 5944 | |
| 5945 | if (!switch_back_to_stepped_thread (ecs)) |
| 5946 | { |
| 5947 | if (debug_infrun) |
| 5948 | fprintf_unfiltered (gdb_stdlog, |
| 5949 | "infrun: random signal, keep going\n"); |
| 5950 | |
| 5951 | keep_going (ecs); |
| 5952 | } |
| 5953 | return; |
| 5954 | } |
| 5955 | |
| 5956 | process_event_stop_test (ecs); |
| 5957 | } |
| 5958 | |
| 5959 | /* Come here when we've got some debug event / signal we can explain |
| 5960 | (IOW, not a random signal), and test whether it should cause a |
| 5961 | stop, or whether we should resume the inferior (transparently). |
| 5962 | E.g., could be a breakpoint whose condition evaluates false; we |
| 5963 | could be still stepping within the line; etc. */ |
| 5964 | |
| 5965 | static void |
| 5966 | process_event_stop_test (struct execution_control_state *ecs) |
| 5967 | { |
| 5968 | struct symtab_and_line stop_pc_sal; |
| 5969 | struct frame_info *frame; |
| 5970 | struct gdbarch *gdbarch; |
| 5971 | CORE_ADDR jmp_buf_pc; |
| 5972 | struct bpstat_what what; |
| 5973 | |
| 5974 | /* Handle cases caused by hitting a breakpoint. */ |
| 5975 | |
| 5976 | frame = get_current_frame (); |
| 5977 | gdbarch = get_frame_arch (frame); |
| 5978 | |
| 5979 | what = bpstat_what (ecs->event_thread->control.stop_bpstat); |
| 5980 | |
| 5981 | if (what.call_dummy) |
| 5982 | { |
| 5983 | stop_stack_dummy = what.call_dummy; |
| 5984 | } |
| 5985 | |
| 5986 | /* A few breakpoint types have callbacks associated (e.g., |
| 5987 | bp_jit_event). Run them now. */ |
| 5988 | bpstat_run_callbacks (ecs->event_thread->control.stop_bpstat); |
| 5989 | |
| 5990 | /* If we hit an internal event that triggers symbol changes, the |
| 5991 | current frame will be invalidated within bpstat_what (e.g., if we |
| 5992 | hit an internal solib event). Re-fetch it. */ |
| 5993 | frame = get_current_frame (); |
| 5994 | gdbarch = get_frame_arch (frame); |
| 5995 | |
| 5996 | switch (what.main_action) |
| 5997 | { |
| 5998 | case BPSTAT_WHAT_SET_LONGJMP_RESUME: |
| 5999 | /* If we hit the breakpoint at longjmp while stepping, we |
| 6000 | install a momentary breakpoint at the target of the |
| 6001 | jmp_buf. */ |
| 6002 | |
| 6003 | if (debug_infrun) |
| 6004 | fprintf_unfiltered (gdb_stdlog, |
| 6005 | "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n"); |
| 6006 | |
| 6007 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6008 | |
| 6009 | if (what.is_longjmp) |
| 6010 | { |
| 6011 | struct value *arg_value; |
| 6012 | |
| 6013 | /* If we set the longjmp breakpoint via a SystemTap probe, |
| 6014 | then use it to extract the arguments. The destination PC |
| 6015 | is the third argument to the probe. */ |
| 6016 | arg_value = probe_safe_evaluate_at_pc (frame, 2); |
| 6017 | if (arg_value) |
| 6018 | { |
| 6019 | jmp_buf_pc = value_as_address (arg_value); |
| 6020 | jmp_buf_pc = gdbarch_addr_bits_remove (gdbarch, jmp_buf_pc); |
| 6021 | } |
| 6022 | else if (!gdbarch_get_longjmp_target_p (gdbarch) |
| 6023 | || !gdbarch_get_longjmp_target (gdbarch, |
| 6024 | frame, &jmp_buf_pc)) |
| 6025 | { |
| 6026 | if (debug_infrun) |
| 6027 | fprintf_unfiltered (gdb_stdlog, |
| 6028 | "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME " |
| 6029 | "(!gdbarch_get_longjmp_target)\n"); |
| 6030 | keep_going (ecs); |
| 6031 | return; |
| 6032 | } |
| 6033 | |
| 6034 | /* Insert a breakpoint at resume address. */ |
| 6035 | insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc); |
| 6036 | } |
| 6037 | else |
| 6038 | check_exception_resume (ecs, frame); |
| 6039 | keep_going (ecs); |
| 6040 | return; |
| 6041 | |
| 6042 | case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME: |
| 6043 | { |
| 6044 | struct frame_info *init_frame; |
| 6045 | |
| 6046 | /* There are several cases to consider. |
| 6047 | |
| 6048 | 1. The initiating frame no longer exists. In this case we |
| 6049 | must stop, because the exception or longjmp has gone too |
| 6050 | far. |
| 6051 | |
| 6052 | 2. The initiating frame exists, and is the same as the |
| 6053 | current frame. We stop, because the exception or longjmp |
| 6054 | has been caught. |
| 6055 | |
| 6056 | 3. The initiating frame exists and is different from the |
| 6057 | current frame. This means the exception or longjmp has |
| 6058 | been caught beneath the initiating frame, so keep going. |
| 6059 | |
| 6060 | 4. longjmp breakpoint has been placed just to protect |
| 6061 | against stale dummy frames and user is not interested in |
| 6062 | stopping around longjmps. */ |
| 6063 | |
| 6064 | if (debug_infrun) |
| 6065 | fprintf_unfiltered (gdb_stdlog, |
| 6066 | "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n"); |
| 6067 | |
| 6068 | gdb_assert (ecs->event_thread->control.exception_resume_breakpoint |
| 6069 | != NULL); |
| 6070 | delete_exception_resume_breakpoint (ecs->event_thread); |
| 6071 | |
| 6072 | if (what.is_longjmp) |
| 6073 | { |
| 6074 | check_longjmp_breakpoint_for_call_dummy (ecs->event_thread); |
| 6075 | |
| 6076 | if (!frame_id_p (ecs->event_thread->initiating_frame)) |
| 6077 | { |
| 6078 | /* Case 4. */ |
| 6079 | keep_going (ecs); |
| 6080 | return; |
| 6081 | } |
| 6082 | } |
| 6083 | |
| 6084 | init_frame = frame_find_by_id (ecs->event_thread->initiating_frame); |
| 6085 | |
| 6086 | if (init_frame) |
| 6087 | { |
| 6088 | struct frame_id current_id |
| 6089 | = get_frame_id (get_current_frame ()); |
| 6090 | if (frame_id_eq (current_id, |
| 6091 | ecs->event_thread->initiating_frame)) |
| 6092 | { |
| 6093 | /* Case 2. Fall through. */ |
| 6094 | } |
| 6095 | else |
| 6096 | { |
| 6097 | /* Case 3. */ |
| 6098 | keep_going (ecs); |
| 6099 | return; |
| 6100 | } |
| 6101 | } |
| 6102 | |
| 6103 | /* For Cases 1 and 2, remove the step-resume breakpoint, if it |
| 6104 | exists. */ |
| 6105 | delete_step_resume_breakpoint (ecs->event_thread); |
| 6106 | |
| 6107 | end_stepping_range (ecs); |
| 6108 | } |
| 6109 | return; |
| 6110 | |
| 6111 | case BPSTAT_WHAT_SINGLE: |
| 6112 | if (debug_infrun) |
| 6113 | fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n"); |
| 6114 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6115 | /* Still need to check other stuff, at least the case where we |
| 6116 | are stepping and step out of the right range. */ |
| 6117 | break; |
| 6118 | |
| 6119 | case BPSTAT_WHAT_STEP_RESUME: |
| 6120 | if (debug_infrun) |
| 6121 | fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n"); |
| 6122 | |
| 6123 | delete_step_resume_breakpoint (ecs->event_thread); |
| 6124 | if (ecs->event_thread->control.proceed_to_finish |
| 6125 | && execution_direction == EXEC_REVERSE) |
| 6126 | { |
| 6127 | struct thread_info *tp = ecs->event_thread; |
| 6128 | |
| 6129 | /* We are finishing a function in reverse, and just hit the |
| 6130 | step-resume breakpoint at the start address of the |
| 6131 | function, and we're almost there -- just need to back up |
| 6132 | by one more single-step, which should take us back to the |
| 6133 | function call. */ |
| 6134 | tp->control.step_range_start = tp->control.step_range_end = 1; |
| 6135 | keep_going (ecs); |
| 6136 | return; |
| 6137 | } |
| 6138 | fill_in_stop_func (gdbarch, ecs); |
| 6139 | if (stop_pc == ecs->stop_func_start |
| 6140 | && execution_direction == EXEC_REVERSE) |
| 6141 | { |
| 6142 | /* We are stepping over a function call in reverse, and just |
| 6143 | hit the step-resume breakpoint at the start address of |
| 6144 | the function. Go back to single-stepping, which should |
| 6145 | take us back to the function call. */ |
| 6146 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6147 | keep_going (ecs); |
| 6148 | return; |
| 6149 | } |
| 6150 | break; |
| 6151 | |
| 6152 | case BPSTAT_WHAT_STOP_NOISY: |
| 6153 | if (debug_infrun) |
| 6154 | fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n"); |
| 6155 | stop_print_frame = 1; |
| 6156 | |
| 6157 | /* Assume the thread stopped for a breapoint. We'll still check |
| 6158 | whether a/the breakpoint is there when the thread is next |
| 6159 | resumed. */ |
| 6160 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6161 | |
| 6162 | stop_waiting (ecs); |
| 6163 | return; |
| 6164 | |
| 6165 | case BPSTAT_WHAT_STOP_SILENT: |
| 6166 | if (debug_infrun) |
| 6167 | fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n"); |
| 6168 | stop_print_frame = 0; |
| 6169 | |
| 6170 | /* Assume the thread stopped for a breapoint. We'll still check |
| 6171 | whether a/the breakpoint is there when the thread is next |
| 6172 | resumed. */ |
| 6173 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6174 | stop_waiting (ecs); |
| 6175 | return; |
| 6176 | |
| 6177 | case BPSTAT_WHAT_HP_STEP_RESUME: |
| 6178 | if (debug_infrun) |
| 6179 | fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n"); |
| 6180 | |
| 6181 | delete_step_resume_breakpoint (ecs->event_thread); |
| 6182 | if (ecs->event_thread->step_after_step_resume_breakpoint) |
| 6183 | { |
| 6184 | /* Back when the step-resume breakpoint was inserted, we |
| 6185 | were trying to single-step off a breakpoint. Go back to |
| 6186 | doing that. */ |
| 6187 | ecs->event_thread->step_after_step_resume_breakpoint = 0; |
| 6188 | ecs->event_thread->stepping_over_breakpoint = 1; |
| 6189 | keep_going (ecs); |
| 6190 | return; |
| 6191 | } |
| 6192 | break; |
| 6193 | |
| 6194 | case BPSTAT_WHAT_KEEP_CHECKING: |
| 6195 | break; |
| 6196 | } |
| 6197 | |
| 6198 | /* If we stepped a permanent breakpoint and we had a high priority |
| 6199 | step-resume breakpoint for the address we stepped, but we didn't |
| 6200 | hit it, then we must have stepped into the signal handler. The |
| 6201 | step-resume was only necessary to catch the case of _not_ |
| 6202 | stepping into the handler, so delete it, and fall through to |
| 6203 | checking whether the step finished. */ |
| 6204 | if (ecs->event_thread->stepped_breakpoint) |
| 6205 | { |
| 6206 | struct breakpoint *sr_bp |
| 6207 | = ecs->event_thread->control.step_resume_breakpoint; |
| 6208 | |
| 6209 | if (sr_bp != NULL |
| 6210 | && sr_bp->loc->permanent |
| 6211 | && sr_bp->type == bp_hp_step_resume |
| 6212 | && sr_bp->loc->address == ecs->event_thread->prev_pc) |
| 6213 | { |
| 6214 | if (debug_infrun) |
| 6215 | fprintf_unfiltered (gdb_stdlog, |
| 6216 | "infrun: stepped permanent breakpoint, stopped in " |
| 6217 | "handler\n"); |
| 6218 | delete_step_resume_breakpoint (ecs->event_thread); |
| 6219 | ecs->event_thread->step_after_step_resume_breakpoint = 0; |
| 6220 | } |
| 6221 | } |
| 6222 | |
| 6223 | /* We come here if we hit a breakpoint but should not stop for it. |
| 6224 | Possibly we also were stepping and should stop for that. So fall |
| 6225 | through and test for stepping. But, if not stepping, do not |
| 6226 | stop. */ |
| 6227 | |
| 6228 | /* In all-stop mode, if we're currently stepping but have stopped in |
| 6229 | some other thread, we need to switch back to the stepped thread. */ |
| 6230 | if (switch_back_to_stepped_thread (ecs)) |
| 6231 | return; |
| 6232 | |
| 6233 | if (ecs->event_thread->control.step_resume_breakpoint) |
| 6234 | { |
| 6235 | if (debug_infrun) |
| 6236 | fprintf_unfiltered (gdb_stdlog, |
| 6237 | "infrun: step-resume breakpoint is inserted\n"); |
| 6238 | |
| 6239 | /* Having a step-resume breakpoint overrides anything |
| 6240 | else having to do with stepping commands until |
| 6241 | that breakpoint is reached. */ |
| 6242 | keep_going (ecs); |
| 6243 | return; |
| 6244 | } |
| 6245 | |
| 6246 | if (ecs->event_thread->control.step_range_end == 0) |
| 6247 | { |
| 6248 | if (debug_infrun) |
| 6249 | fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n"); |
| 6250 | /* Likewise if we aren't even stepping. */ |
| 6251 | keep_going (ecs); |
| 6252 | return; |
| 6253 | } |
| 6254 | |
| 6255 | /* Re-fetch current thread's frame in case the code above caused |
| 6256 | the frame cache to be re-initialized, making our FRAME variable |
| 6257 | a dangling pointer. */ |
| 6258 | frame = get_current_frame (); |
| 6259 | gdbarch = get_frame_arch (frame); |
| 6260 | fill_in_stop_func (gdbarch, ecs); |
| 6261 | |
| 6262 | /* If stepping through a line, keep going if still within it. |
| 6263 | |
| 6264 | Note that step_range_end is the address of the first instruction |
| 6265 | beyond the step range, and NOT the address of the last instruction |
| 6266 | within it! |
| 6267 | |
| 6268 | Note also that during reverse execution, we may be stepping |
| 6269 | through a function epilogue and therefore must detect when |
| 6270 | the current-frame changes in the middle of a line. */ |
| 6271 | |
| 6272 | if (pc_in_thread_step_range (stop_pc, ecs->event_thread) |
| 6273 | && (execution_direction != EXEC_REVERSE |
| 6274 | || frame_id_eq (get_frame_id (frame), |
| 6275 | ecs->event_thread->control.step_frame_id))) |
| 6276 | { |
| 6277 | if (debug_infrun) |
| 6278 | fprintf_unfiltered |
| 6279 | (gdb_stdlog, "infrun: stepping inside range [%s-%s]\n", |
| 6280 | paddress (gdbarch, ecs->event_thread->control.step_range_start), |
| 6281 | paddress (gdbarch, ecs->event_thread->control.step_range_end)); |
| 6282 | |
| 6283 | /* Tentatively re-enable range stepping; `resume' disables it if |
| 6284 | necessary (e.g., if we're stepping over a breakpoint or we |
| 6285 | have software watchpoints). */ |
| 6286 | ecs->event_thread->control.may_range_step = 1; |
| 6287 | |
| 6288 | /* When stepping backward, stop at beginning of line range |
| 6289 | (unless it's the function entry point, in which case |
| 6290 | keep going back to the call point). */ |
| 6291 | if (stop_pc == ecs->event_thread->control.step_range_start |
| 6292 | && stop_pc != ecs->stop_func_start |
| 6293 | && execution_direction == EXEC_REVERSE) |
| 6294 | end_stepping_range (ecs); |
| 6295 | else |
| 6296 | keep_going (ecs); |
| 6297 | |
| 6298 | return; |
| 6299 | } |
| 6300 | |
| 6301 | /* We stepped out of the stepping range. */ |
| 6302 | |
| 6303 | /* If we are stepping at the source level and entered the runtime |
| 6304 | loader dynamic symbol resolution code... |
| 6305 | |
| 6306 | EXEC_FORWARD: we keep on single stepping until we exit the run |
| 6307 | time loader code and reach the callee's address. |
| 6308 | |
| 6309 | EXEC_REVERSE: we've already executed the callee (backward), and |
| 6310 | the runtime loader code is handled just like any other |
| 6311 | undebuggable function call. Now we need only keep stepping |
| 6312 | backward through the trampoline code, and that's handled further |
| 6313 | down, so there is nothing for us to do here. */ |
| 6314 | |
| 6315 | if (execution_direction != EXEC_REVERSE |
| 6316 | && ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE |
| 6317 | && in_solib_dynsym_resolve_code (stop_pc)) |
| 6318 | { |
| 6319 | CORE_ADDR pc_after_resolver = |
| 6320 | gdbarch_skip_solib_resolver (gdbarch, stop_pc); |
| 6321 | |
| 6322 | if (debug_infrun) |
| 6323 | fprintf_unfiltered (gdb_stdlog, |
| 6324 | "infrun: stepped into dynsym resolve code\n"); |
| 6325 | |
| 6326 | if (pc_after_resolver) |
| 6327 | { |
| 6328 | /* Set up a step-resume breakpoint at the address |
| 6329 | indicated by SKIP_SOLIB_RESOLVER. */ |
| 6330 | struct symtab_and_line sr_sal; |
| 6331 | |
| 6332 | init_sal (&sr_sal); |
| 6333 | sr_sal.pc = pc_after_resolver; |
| 6334 | sr_sal.pspace = get_frame_program_space (frame); |
| 6335 | |
| 6336 | insert_step_resume_breakpoint_at_sal (gdbarch, |
| 6337 | sr_sal, null_frame_id); |
| 6338 | } |
| 6339 | |
| 6340 | keep_going (ecs); |
| 6341 | return; |
| 6342 | } |
| 6343 | |
| 6344 | if (ecs->event_thread->control.step_range_end != 1 |
| 6345 | && (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE |
| 6346 | || ecs->event_thread->control.step_over_calls == STEP_OVER_ALL) |
| 6347 | && get_frame_type (frame) == SIGTRAMP_FRAME) |
| 6348 | { |
| 6349 | if (debug_infrun) |
| 6350 | fprintf_unfiltered (gdb_stdlog, |
| 6351 | "infrun: stepped into signal trampoline\n"); |
| 6352 | /* The inferior, while doing a "step" or "next", has ended up in |
| 6353 | a signal trampoline (either by a signal being delivered or by |
| 6354 | the signal handler returning). Just single-step until the |
| 6355 | inferior leaves the trampoline (either by calling the handler |
| 6356 | or returning). */ |
| 6357 | keep_going (ecs); |
| 6358 | return; |
| 6359 | } |
| 6360 | |
| 6361 | /* If we're in the return path from a shared library trampoline, |
| 6362 | we want to proceed through the trampoline when stepping. */ |
| 6363 | /* macro/2012-04-25: This needs to come before the subroutine |
| 6364 | call check below as on some targets return trampolines look |
| 6365 | like subroutine calls (MIPS16 return thunks). */ |
| 6366 | if (gdbarch_in_solib_return_trampoline (gdbarch, |
| 6367 | stop_pc, ecs->stop_func_name) |
| 6368 | && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE) |
| 6369 | { |
| 6370 | /* Determine where this trampoline returns. */ |
| 6371 | CORE_ADDR real_stop_pc; |
| 6372 | |
| 6373 | real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc); |
| 6374 | |
| 6375 | if (debug_infrun) |
| 6376 | fprintf_unfiltered (gdb_stdlog, |
| 6377 | "infrun: stepped into solib return tramp\n"); |
| 6378 | |
| 6379 | /* Only proceed through if we know where it's going. */ |
| 6380 | if (real_stop_pc) |
| 6381 | { |
| 6382 | /* And put the step-breakpoint there and go until there. */ |
| 6383 | struct symtab_and_line sr_sal; |
| 6384 | |
| 6385 | init_sal (&sr_sal); /* initialize to zeroes */ |
| 6386 | sr_sal.pc = real_stop_pc; |
| 6387 | sr_sal.section = find_pc_overlay (sr_sal.pc); |
| 6388 | sr_sal.pspace = get_frame_program_space (frame); |
| 6389 | |
| 6390 | /* Do not specify what the fp should be when we stop since |
| 6391 | on some machines the prologue is where the new fp value |
| 6392 | is established. */ |
| 6393 | insert_step_resume_breakpoint_at_sal (gdbarch, |
| 6394 | sr_sal, null_frame_id); |
| 6395 | |
| 6396 | /* Restart without fiddling with the step ranges or |
| 6397 | other state. */ |
| 6398 | keep_going (ecs); |
| 6399 | return; |
| 6400 | } |
| 6401 | } |
| 6402 | |
| 6403 | /* Check for subroutine calls. The check for the current frame |
| 6404 | equalling the step ID is not necessary - the check of the |
| 6405 | previous frame's ID is sufficient - but it is a common case and |
| 6406 | cheaper than checking the previous frame's ID. |
| 6407 | |
| 6408 | NOTE: frame_id_eq will never report two invalid frame IDs as |
| 6409 | being equal, so to get into this block, both the current and |
| 6410 | previous frame must have valid frame IDs. */ |
| 6411 | /* The outer_frame_id check is a heuristic to detect stepping |
| 6412 | through startup code. If we step over an instruction which |
| 6413 | sets the stack pointer from an invalid value to a valid value, |
| 6414 | we may detect that as a subroutine call from the mythical |
| 6415 | "outermost" function. This could be fixed by marking |
| 6416 | outermost frames as !stack_p,code_p,special_p. Then the |
| 6417 | initial outermost frame, before sp was valid, would |
| 6418 | have code_addr == &_start. See the comment in frame_id_eq |
| 6419 | for more. */ |
| 6420 | if (!frame_id_eq (get_stack_frame_id (frame), |
| 6421 | ecs->event_thread->control.step_stack_frame_id) |
| 6422 | && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()), |
| 6423 | ecs->event_thread->control.step_stack_frame_id) |
| 6424 | && (!frame_id_eq (ecs->event_thread->control.step_stack_frame_id, |
| 6425 | outer_frame_id) |
| 6426 | || (ecs->event_thread->control.step_start_function |
| 6427 | != find_pc_function (stop_pc))))) |
| 6428 | { |
| 6429 | CORE_ADDR real_stop_pc; |
| 6430 | |
| 6431 | if (debug_infrun) |
| 6432 | fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n"); |
| 6433 | |
| 6434 | if (ecs->event_thread->control.step_over_calls == STEP_OVER_NONE) |
| 6435 | { |
| 6436 | /* I presume that step_over_calls is only 0 when we're |
| 6437 | supposed to be stepping at the assembly language level |
| 6438 | ("stepi"). Just stop. */ |
| 6439 | /* And this works the same backward as frontward. MVS */ |
| 6440 | end_stepping_range (ecs); |
| 6441 | return; |
| 6442 | } |
| 6443 | |
| 6444 | /* Reverse stepping through solib trampolines. */ |
| 6445 | |
| 6446 | if (execution_direction == EXEC_REVERSE |
| 6447 | && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE |
| 6448 | && (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc) |
| 6449 | || (ecs->stop_func_start == 0 |
| 6450 | && in_solib_dynsym_resolve_code (stop_pc)))) |
| 6451 | { |
| 6452 | /* Any solib trampoline code can be handled in reverse |
| 6453 | by simply continuing to single-step. We have already |
| 6454 | executed the solib function (backwards), and a few |
| 6455 | steps will take us back through the trampoline to the |
| 6456 | caller. */ |
| 6457 | keep_going (ecs); |
| 6458 | return; |
| 6459 | } |
| 6460 | |
| 6461 | if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL) |
| 6462 | { |
| 6463 | /* We're doing a "next". |
| 6464 | |
| 6465 | Normal (forward) execution: set a breakpoint at the |
| 6466 | callee's return address (the address at which the caller |
| 6467 | will resume). |
| 6468 | |
| 6469 | Reverse (backward) execution. set the step-resume |
| 6470 | breakpoint at the start of the function that we just |
| 6471 | stepped into (backwards), and continue to there. When we |
| 6472 | get there, we'll need to single-step back to the caller. */ |
| 6473 | |
| 6474 | if (execution_direction == EXEC_REVERSE) |
| 6475 | { |
| 6476 | /* If we're already at the start of the function, we've either |
| 6477 | just stepped backward into a single instruction function, |
| 6478 | or stepped back out of a signal handler to the first instruction |
| 6479 | of the function. Just keep going, which will single-step back |
| 6480 | to the caller. */ |
| 6481 | if (ecs->stop_func_start != stop_pc && ecs->stop_func_start != 0) |
| 6482 | { |
| 6483 | struct symtab_and_line sr_sal; |
| 6484 | |
| 6485 | /* Normal function call return (static or dynamic). */ |
| 6486 | init_sal (&sr_sal); |
| 6487 | sr_sal.pc = ecs->stop_func_start; |
| 6488 | sr_sal.pspace = get_frame_program_space (frame); |
| 6489 | insert_step_resume_breakpoint_at_sal (gdbarch, |
| 6490 | sr_sal, null_frame_id); |
| 6491 | } |
| 6492 | } |
| 6493 | else |
| 6494 | insert_step_resume_breakpoint_at_caller (frame); |
| 6495 | |
| 6496 | keep_going (ecs); |
| 6497 | return; |
| 6498 | } |
| 6499 | |
| 6500 | /* If we are in a function call trampoline (a stub between the |
| 6501 | calling routine and the real function), locate the real |
| 6502 | function. That's what tells us (a) whether we want to step |
| 6503 | into it at all, and (b) what prologue we want to run to the |
| 6504 | end of, if we do step into it. */ |
| 6505 | real_stop_pc = skip_language_trampoline (frame, stop_pc); |
| 6506 | if (real_stop_pc == 0) |
| 6507 | real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc); |
| 6508 | if (real_stop_pc != 0) |
| 6509 | ecs->stop_func_start = real_stop_pc; |
| 6510 | |
| 6511 | if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc)) |
| 6512 | { |
| 6513 | struct symtab_and_line sr_sal; |
| 6514 | |
| 6515 | init_sal (&sr_sal); |
| 6516 | sr_sal.pc = ecs->stop_func_start; |
| 6517 | sr_sal.pspace = get_frame_program_space (frame); |
| 6518 | |
| 6519 | insert_step_resume_breakpoint_at_sal (gdbarch, |
| 6520 | sr_sal, null_frame_id); |
| 6521 | keep_going (ecs); |
| 6522 | return; |
| 6523 | } |
| 6524 | |
| 6525 | /* If we have line number information for the function we are |
| 6526 | thinking of stepping into and the function isn't on the skip |
| 6527 | list, step into it. |
| 6528 | |
| 6529 | If there are several symtabs at that PC (e.g. with include |
| 6530 | files), just want to know whether *any* of them have line |
| 6531 | numbers. find_pc_line handles this. */ |
| 6532 | { |
| 6533 | struct symtab_and_line tmp_sal; |
| 6534 | |
| 6535 | tmp_sal = find_pc_line (ecs->stop_func_start, 0); |
| 6536 | if (tmp_sal.line != 0 |
| 6537 | && !function_name_is_marked_for_skip (ecs->stop_func_name, |
| 6538 | &tmp_sal)) |
| 6539 | { |
| 6540 | if (execution_direction == EXEC_REVERSE) |
| 6541 | handle_step_into_function_backward (gdbarch, ecs); |
| 6542 | else |
| 6543 | handle_step_into_function (gdbarch, ecs); |
| 6544 | return; |
| 6545 | } |
| 6546 | } |
| 6547 | |
| 6548 | /* If we have no line number and the step-stop-if-no-debug is |
| 6549 | set, we stop the step so that the user has a chance to switch |
| 6550 | in assembly mode. */ |
| 6551 | if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE |
| 6552 | && step_stop_if_no_debug) |
| 6553 | { |
| 6554 | end_stepping_range (ecs); |
| 6555 | return; |
| 6556 | } |
| 6557 | |
| 6558 | if (execution_direction == EXEC_REVERSE) |
| 6559 | { |
| 6560 | /* If we're already at the start of the function, we've either just |
| 6561 | stepped backward into a single instruction function without line |
| 6562 | number info, or stepped back out of a signal handler to the first |
| 6563 | instruction of the function without line number info. Just keep |
| 6564 | going, which will single-step back to the caller. */ |
| 6565 | if (ecs->stop_func_start != stop_pc) |
| 6566 | { |
| 6567 | /* Set a breakpoint at callee's start address. |
| 6568 | From there we can step once and be back in the caller. */ |
| 6569 | struct symtab_and_line sr_sal; |
| 6570 | |
| 6571 | init_sal (&sr_sal); |
| 6572 | sr_sal.pc = ecs->stop_func_start; |
| 6573 | sr_sal.pspace = get_frame_program_space (frame); |
| 6574 | insert_step_resume_breakpoint_at_sal (gdbarch, |
| 6575 | sr_sal, null_frame_id); |
| 6576 | } |
| 6577 | } |
| 6578 | else |
| 6579 | /* Set a breakpoint at callee's return address (the address |
| 6580 | at which the caller will resume). */ |
| 6581 | insert_step_resume_breakpoint_at_caller (frame); |
| 6582 | |
| 6583 | keep_going (ecs); |
| 6584 | return; |
| 6585 | } |
| 6586 | |
| 6587 | /* Reverse stepping through solib trampolines. */ |
| 6588 | |
| 6589 | if (execution_direction == EXEC_REVERSE |
| 6590 | && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE) |
| 6591 | { |
| 6592 | if (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc) |
| 6593 | || (ecs->stop_func_start == 0 |
| 6594 | && in_solib_dynsym_resolve_code (stop_pc))) |
| 6595 | { |
| 6596 | /* Any solib trampoline code can be handled in reverse |
| 6597 | by simply continuing to single-step. We have already |
| 6598 | executed the solib function (backwards), and a few |
| 6599 | steps will take us back through the trampoline to the |
| 6600 | caller. */ |
| 6601 | keep_going (ecs); |
| 6602 | return; |
| 6603 | } |
| 6604 | else if (in_solib_dynsym_resolve_code (stop_pc)) |
| 6605 | { |
| 6606 | /* Stepped backward into the solib dynsym resolver. |
| 6607 | Set a breakpoint at its start and continue, then |
| 6608 | one more step will take us out. */ |
| 6609 | struct symtab_and_line sr_sal; |
| 6610 | |
| 6611 | init_sal (&sr_sal); |
| 6612 | sr_sal.pc = ecs->stop_func_start; |
| 6613 | sr_sal.pspace = get_frame_program_space (frame); |
| 6614 | insert_step_resume_breakpoint_at_sal (gdbarch, |
| 6615 | sr_sal, null_frame_id); |
| 6616 | keep_going (ecs); |
| 6617 | return; |
| 6618 | } |
| 6619 | } |
| 6620 | |
| 6621 | stop_pc_sal = find_pc_line (stop_pc, 0); |
| 6622 | |
| 6623 | /* NOTE: tausq/2004-05-24: This if block used to be done before all |
| 6624 | the trampoline processing logic, however, there are some trampolines |
| 6625 | that have no names, so we should do trampoline handling first. */ |
| 6626 | if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE |
| 6627 | && ecs->stop_func_name == NULL |
| 6628 | && stop_pc_sal.line == 0) |
| 6629 | { |
| 6630 | if (debug_infrun) |
| 6631 | fprintf_unfiltered (gdb_stdlog, |
| 6632 | "infrun: stepped into undebuggable function\n"); |
| 6633 | |
| 6634 | /* The inferior just stepped into, or returned to, an |
| 6635 | undebuggable function (where there is no debugging information |
| 6636 | and no line number corresponding to the address where the |
| 6637 | inferior stopped). Since we want to skip this kind of code, |
| 6638 | we keep going until the inferior returns from this |
| 6639 | function - unless the user has asked us not to (via |
| 6640 | set step-mode) or we no longer know how to get back |
| 6641 | to the call site. */ |
| 6642 | if (step_stop_if_no_debug |
| 6643 | || !frame_id_p (frame_unwind_caller_id (frame))) |
| 6644 | { |
| 6645 | /* If we have no line number and the step-stop-if-no-debug |
| 6646 | is set, we stop the step so that the user has a chance to |
| 6647 | switch in assembly mode. */ |
| 6648 | end_stepping_range (ecs); |
| 6649 | return; |
| 6650 | } |
| 6651 | else |
| 6652 | { |
| 6653 | /* Set a breakpoint at callee's return address (the address |
| 6654 | at which the caller will resume). */ |
| 6655 | insert_step_resume_breakpoint_at_caller (frame); |
| 6656 | keep_going (ecs); |
| 6657 | return; |
| 6658 | } |
| 6659 | } |
| 6660 | |
| 6661 | if (ecs->event_thread->control.step_range_end == 1) |
| 6662 | { |
| 6663 | /* It is stepi or nexti. We always want to stop stepping after |
| 6664 | one instruction. */ |
| 6665 | if (debug_infrun) |
| 6666 | fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n"); |
| 6667 | end_stepping_range (ecs); |
| 6668 | return; |
| 6669 | } |
| 6670 | |
| 6671 | if (stop_pc_sal.line == 0) |
| 6672 | { |
| 6673 | /* We have no line number information. That means to stop |
| 6674 | stepping (does this always happen right after one instruction, |
| 6675 | when we do "s" in a function with no line numbers, |
| 6676 | or can this happen as a result of a return or longjmp?). */ |
| 6677 | if (debug_infrun) |
| 6678 | fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n"); |
| 6679 | end_stepping_range (ecs); |
| 6680 | return; |
| 6681 | } |
| 6682 | |
| 6683 | /* Look for "calls" to inlined functions, part one. If the inline |
| 6684 | frame machinery detected some skipped call sites, we have entered |
| 6685 | a new inline function. */ |
| 6686 | |
| 6687 | if (frame_id_eq (get_frame_id (get_current_frame ()), |
| 6688 | ecs->event_thread->control.step_frame_id) |
| 6689 | && inline_skipped_frames (ecs->ptid)) |
| 6690 | { |
| 6691 | struct symtab_and_line call_sal; |
| 6692 | |
| 6693 | if (debug_infrun) |
| 6694 | fprintf_unfiltered (gdb_stdlog, |
| 6695 | "infrun: stepped into inlined function\n"); |
| 6696 | |
| 6697 | find_frame_sal (get_current_frame (), &call_sal); |
| 6698 | |
| 6699 | if (ecs->event_thread->control.step_over_calls != STEP_OVER_ALL) |
| 6700 | { |
| 6701 | /* For "step", we're going to stop. But if the call site |
| 6702 | for this inlined function is on the same source line as |
| 6703 | we were previously stepping, go down into the function |
| 6704 | first. Otherwise stop at the call site. */ |
| 6705 | |
| 6706 | if (call_sal.line == ecs->event_thread->current_line |
| 6707 | && call_sal.symtab == ecs->event_thread->current_symtab) |
| 6708 | step_into_inline_frame (ecs->ptid); |
| 6709 | |
| 6710 | end_stepping_range (ecs); |
| 6711 | return; |
| 6712 | } |
| 6713 | else |
| 6714 | { |
| 6715 | /* For "next", we should stop at the call site if it is on a |
| 6716 | different source line. Otherwise continue through the |
| 6717 | inlined function. */ |
| 6718 | if (call_sal.line == ecs->event_thread->current_line |
| 6719 | && call_sal.symtab == ecs->event_thread->current_symtab) |
| 6720 | keep_going (ecs); |
| 6721 | else |
| 6722 | end_stepping_range (ecs); |
| 6723 | return; |
| 6724 | } |
| 6725 | } |
| 6726 | |
| 6727 | /* Look for "calls" to inlined functions, part two. If we are still |
| 6728 | in the same real function we were stepping through, but we have |
| 6729 | to go further up to find the exact frame ID, we are stepping |
| 6730 | through a more inlined call beyond its call site. */ |
| 6731 | |
| 6732 | if (get_frame_type (get_current_frame ()) == INLINE_FRAME |
| 6733 | && !frame_id_eq (get_frame_id (get_current_frame ()), |
| 6734 | ecs->event_thread->control.step_frame_id) |
| 6735 | && stepped_in_from (get_current_frame (), |
| 6736 | ecs->event_thread->control.step_frame_id)) |
| 6737 | { |
| 6738 | if (debug_infrun) |
| 6739 | fprintf_unfiltered (gdb_stdlog, |
| 6740 | "infrun: stepping through inlined function\n"); |
| 6741 | |
| 6742 | if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL) |
| 6743 | keep_going (ecs); |
| 6744 | else |
| 6745 | end_stepping_range (ecs); |
| 6746 | return; |
| 6747 | } |
| 6748 | |
| 6749 | if ((stop_pc == stop_pc_sal.pc) |
| 6750 | && (ecs->event_thread->current_line != stop_pc_sal.line |
| 6751 | || ecs->event_thread->current_symtab != stop_pc_sal.symtab)) |
| 6752 | { |
| 6753 | /* We are at the start of a different line. So stop. Note that |
| 6754 | we don't stop if we step into the middle of a different line. |
| 6755 | That is said to make things like for (;;) statements work |
| 6756 | better. */ |
| 6757 | if (debug_infrun) |
| 6758 | fprintf_unfiltered (gdb_stdlog, |
| 6759 | "infrun: stepped to a different line\n"); |
| 6760 | end_stepping_range (ecs); |
| 6761 | return; |
| 6762 | } |
| 6763 | |
| 6764 | /* We aren't done stepping. |
| 6765 | |
| 6766 | Optimize by setting the stepping range to the line. |
| 6767 | (We might not be in the original line, but if we entered a |
| 6768 | new line in mid-statement, we continue stepping. This makes |
| 6769 | things like for(;;) statements work better.) */ |
| 6770 | |
| 6771 | ecs->event_thread->control.step_range_start = stop_pc_sal.pc; |
| 6772 | ecs->event_thread->control.step_range_end = stop_pc_sal.end; |
| 6773 | ecs->event_thread->control.may_range_step = 1; |
| 6774 | set_step_info (frame, stop_pc_sal); |
| 6775 | |
| 6776 | if (debug_infrun) |
| 6777 | fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n"); |
| 6778 | keep_going (ecs); |
| 6779 | } |
| 6780 | |
| 6781 | /* In all-stop mode, if we're currently stepping but have stopped in |
| 6782 | some other thread, we may need to switch back to the stepped |
| 6783 | thread. Returns true we set the inferior running, false if we left |
| 6784 | it stopped (and the event needs further processing). */ |
| 6785 | |
| 6786 | static int |
| 6787 | switch_back_to_stepped_thread (struct execution_control_state *ecs) |
| 6788 | { |
| 6789 | if (!target_is_non_stop_p ()) |
| 6790 | { |
| 6791 | struct thread_info *tp; |
| 6792 | struct thread_info *stepping_thread; |
| 6793 | |
| 6794 | /* If any thread is blocked on some internal breakpoint, and we |
| 6795 | simply need to step over that breakpoint to get it going |
| 6796 | again, do that first. */ |
| 6797 | |
| 6798 | /* However, if we see an event for the stepping thread, then we |
| 6799 | know all other threads have been moved past their breakpoints |
| 6800 | already. Let the caller check whether the step is finished, |
| 6801 | etc., before deciding to move it past a breakpoint. */ |
| 6802 | if (ecs->event_thread->control.step_range_end != 0) |
| 6803 | return 0; |
| 6804 | |
| 6805 | /* Check if the current thread is blocked on an incomplete |
| 6806 | step-over, interrupted by a random signal. */ |
| 6807 | if (ecs->event_thread->control.trap_expected |
| 6808 | && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP) |
| 6809 | { |
| 6810 | if (debug_infrun) |
| 6811 | { |
| 6812 | fprintf_unfiltered (gdb_stdlog, |
| 6813 | "infrun: need to finish step-over of [%s]\n", |
| 6814 | target_pid_to_str (ecs->event_thread->ptid)); |
| 6815 | } |
| 6816 | keep_going (ecs); |
| 6817 | return 1; |
| 6818 | } |
| 6819 | |
| 6820 | /* Check if the current thread is blocked by a single-step |
| 6821 | breakpoint of another thread. */ |
| 6822 | if (ecs->hit_singlestep_breakpoint) |
| 6823 | { |
| 6824 | if (debug_infrun) |
| 6825 | { |
| 6826 | fprintf_unfiltered (gdb_stdlog, |
| 6827 | "infrun: need to step [%s] over single-step " |
| 6828 | "breakpoint\n", |
| 6829 | target_pid_to_str (ecs->ptid)); |
| 6830 | } |
| 6831 | keep_going (ecs); |
| 6832 | return 1; |
| 6833 | } |
| 6834 | |
| 6835 | /* If this thread needs yet another step-over (e.g., stepping |
| 6836 | through a delay slot), do it first before moving on to |
| 6837 | another thread. */ |
| 6838 | if (thread_still_needs_step_over (ecs->event_thread)) |
| 6839 | { |
| 6840 | if (debug_infrun) |
| 6841 | { |
| 6842 | fprintf_unfiltered (gdb_stdlog, |
| 6843 | "infrun: thread [%s] still needs step-over\n", |
| 6844 | target_pid_to_str (ecs->event_thread->ptid)); |
| 6845 | } |
| 6846 | keep_going (ecs); |
| 6847 | return 1; |
| 6848 | } |
| 6849 | |
| 6850 | /* If scheduler locking applies even if not stepping, there's no |
| 6851 | need to walk over threads. Above we've checked whether the |
| 6852 | current thread is stepping. If some other thread not the |
| 6853 | event thread is stepping, then it must be that scheduler |
| 6854 | locking is not in effect. */ |
| 6855 | if (schedlock_applies (ecs->event_thread)) |
| 6856 | return 0; |
| 6857 | |
| 6858 | /* Otherwise, we no longer expect a trap in the current thread. |
| 6859 | Clear the trap_expected flag before switching back -- this is |
| 6860 | what keep_going does as well, if we call it. */ |
| 6861 | ecs->event_thread->control.trap_expected = 0; |
| 6862 | |
| 6863 | /* Likewise, clear the signal if it should not be passed. */ |
| 6864 | if (!signal_program[ecs->event_thread->suspend.stop_signal]) |
| 6865 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 6866 | |
| 6867 | /* Do all pending step-overs before actually proceeding with |
| 6868 | step/next/etc. */ |
| 6869 | if (start_step_over ()) |
| 6870 | { |
| 6871 | prepare_to_wait (ecs); |
| 6872 | return 1; |
| 6873 | } |
| 6874 | |
| 6875 | /* Look for the stepping/nexting thread. */ |
| 6876 | stepping_thread = NULL; |
| 6877 | |
| 6878 | ALL_NON_EXITED_THREADS (tp) |
| 6879 | { |
| 6880 | /* Ignore threads of processes the caller is not |
| 6881 | resuming. */ |
| 6882 | if (!sched_multi |
| 6883 | && ptid_get_pid (tp->ptid) != ptid_get_pid (ecs->ptid)) |
| 6884 | continue; |
| 6885 | |
| 6886 | /* When stepping over a breakpoint, we lock all threads |
| 6887 | except the one that needs to move past the breakpoint. |
| 6888 | If a non-event thread has this set, the "incomplete |
| 6889 | step-over" check above should have caught it earlier. */ |
| 6890 | if (tp->control.trap_expected) |
| 6891 | { |
| 6892 | internal_error (__FILE__, __LINE__, |
| 6893 | "[%s] has inconsistent state: " |
| 6894 | "trap_expected=%d\n", |
| 6895 | target_pid_to_str (tp->ptid), |
| 6896 | tp->control.trap_expected); |
| 6897 | } |
| 6898 | |
| 6899 | /* Did we find the stepping thread? */ |
| 6900 | if (tp->control.step_range_end) |
| 6901 | { |
| 6902 | /* Yep. There should only one though. */ |
| 6903 | gdb_assert (stepping_thread == NULL); |
| 6904 | |
| 6905 | /* The event thread is handled at the top, before we |
| 6906 | enter this loop. */ |
| 6907 | gdb_assert (tp != ecs->event_thread); |
| 6908 | |
| 6909 | /* If some thread other than the event thread is |
| 6910 | stepping, then scheduler locking can't be in effect, |
| 6911 | otherwise we wouldn't have resumed the current event |
| 6912 | thread in the first place. */ |
| 6913 | gdb_assert (!schedlock_applies (tp)); |
| 6914 | |
| 6915 | stepping_thread = tp; |
| 6916 | } |
| 6917 | } |
| 6918 | |
| 6919 | if (stepping_thread != NULL) |
| 6920 | { |
| 6921 | if (debug_infrun) |
| 6922 | fprintf_unfiltered (gdb_stdlog, |
| 6923 | "infrun: switching back to stepped thread\n"); |
| 6924 | |
| 6925 | if (keep_going_stepped_thread (stepping_thread)) |
| 6926 | { |
| 6927 | prepare_to_wait (ecs); |
| 6928 | return 1; |
| 6929 | } |
| 6930 | } |
| 6931 | } |
| 6932 | |
| 6933 | return 0; |
| 6934 | } |
| 6935 | |
| 6936 | /* Set a previously stepped thread back to stepping. Returns true on |
| 6937 | success, false if the resume is not possible (e.g., the thread |
| 6938 | vanished). */ |
| 6939 | |
| 6940 | static int |
| 6941 | keep_going_stepped_thread (struct thread_info *tp) |
| 6942 | { |
| 6943 | struct frame_info *frame; |
| 6944 | struct gdbarch *gdbarch; |
| 6945 | struct execution_control_state ecss; |
| 6946 | struct execution_control_state *ecs = &ecss; |
| 6947 | |
| 6948 | /* If the stepping thread exited, then don't try to switch back and |
| 6949 | resume it, which could fail in several different ways depending |
| 6950 | on the target. Instead, just keep going. |
| 6951 | |
| 6952 | We can find a stepping dead thread in the thread list in two |
| 6953 | cases: |
| 6954 | |
| 6955 | - The target supports thread exit events, and when the target |
| 6956 | tries to delete the thread from the thread list, inferior_ptid |
| 6957 | pointed at the exiting thread. In such case, calling |
| 6958 | delete_thread does not really remove the thread from the list; |
| 6959 | instead, the thread is left listed, with 'exited' state. |
| 6960 | |
| 6961 | - The target's debug interface does not support thread exit |
| 6962 | events, and so we have no idea whatsoever if the previously |
| 6963 | stepping thread is still alive. For that reason, we need to |
| 6964 | synchronously query the target now. */ |
| 6965 | |
| 6966 | if (is_exited (tp->ptid) |
| 6967 | || !target_thread_alive (tp->ptid)) |
| 6968 | { |
| 6969 | if (debug_infrun) |
| 6970 | fprintf_unfiltered (gdb_stdlog, |
| 6971 | "infrun: not resuming previously " |
| 6972 | "stepped thread, it has vanished\n"); |
| 6973 | |
| 6974 | delete_thread (tp->ptid); |
| 6975 | return 0; |
| 6976 | } |
| 6977 | |
| 6978 | if (debug_infrun) |
| 6979 | fprintf_unfiltered (gdb_stdlog, |
| 6980 | "infrun: resuming previously stepped thread\n"); |
| 6981 | |
| 6982 | reset_ecs (ecs, tp); |
| 6983 | switch_to_thread (tp->ptid); |
| 6984 | |
| 6985 | stop_pc = regcache_read_pc (get_thread_regcache (tp->ptid)); |
| 6986 | frame = get_current_frame (); |
| 6987 | gdbarch = get_frame_arch (frame); |
| 6988 | |
| 6989 | /* If the PC of the thread we were trying to single-step has |
| 6990 | changed, then that thread has trapped or been signaled, but the |
| 6991 | event has not been reported to GDB yet. Re-poll the target |
| 6992 | looking for this particular thread's event (i.e. temporarily |
| 6993 | enable schedlock) by: |
| 6994 | |
| 6995 | - setting a break at the current PC |
| 6996 | - resuming that particular thread, only (by setting trap |
| 6997 | expected) |
| 6998 | |
| 6999 | This prevents us continuously moving the single-step breakpoint |
| 7000 | forward, one instruction at a time, overstepping. */ |
| 7001 | |
| 7002 | if (stop_pc != tp->prev_pc) |
| 7003 | { |
| 7004 | ptid_t resume_ptid; |
| 7005 | |
| 7006 | if (debug_infrun) |
| 7007 | fprintf_unfiltered (gdb_stdlog, |
| 7008 | "infrun: expected thread advanced also (%s -> %s)\n", |
| 7009 | paddress (target_gdbarch (), tp->prev_pc), |
| 7010 | paddress (target_gdbarch (), stop_pc)); |
| 7011 | |
| 7012 | /* Clear the info of the previous step-over, as it's no longer |
| 7013 | valid (if the thread was trying to step over a breakpoint, it |
| 7014 | has already succeeded). It's what keep_going would do too, |
| 7015 | if we called it. Do this before trying to insert the sss |
| 7016 | breakpoint, otherwise if we were previously trying to step |
| 7017 | over this exact address in another thread, the breakpoint is |
| 7018 | skipped. */ |
| 7019 | clear_step_over_info (); |
| 7020 | tp->control.trap_expected = 0; |
| 7021 | |
| 7022 | insert_single_step_breakpoint (get_frame_arch (frame), |
| 7023 | get_frame_address_space (frame), |
| 7024 | stop_pc); |
| 7025 | |
| 7026 | tp->resumed = 1; |
| 7027 | resume_ptid = internal_resume_ptid (tp->control.stepping_command); |
| 7028 | do_target_resume (resume_ptid, 0, GDB_SIGNAL_0); |
| 7029 | } |
| 7030 | else |
| 7031 | { |
| 7032 | if (debug_infrun) |
| 7033 | fprintf_unfiltered (gdb_stdlog, |
| 7034 | "infrun: expected thread still hasn't advanced\n"); |
| 7035 | |
| 7036 | keep_going_pass_signal (ecs); |
| 7037 | } |
| 7038 | return 1; |
| 7039 | } |
| 7040 | |
| 7041 | /* Is thread TP in the middle of (software or hardware) |
| 7042 | single-stepping? (Note the result of this function must never be |
| 7043 | passed directly as target_resume's STEP parameter.) */ |
| 7044 | |
| 7045 | static int |
| 7046 | currently_stepping (struct thread_info *tp) |
| 7047 | { |
| 7048 | return ((tp->control.step_range_end |
| 7049 | && tp->control.step_resume_breakpoint == NULL) |
| 7050 | || tp->control.trap_expected |
| 7051 | || tp->stepped_breakpoint |
| 7052 | || bpstat_should_step ()); |
| 7053 | } |
| 7054 | |
| 7055 | /* Inferior has stepped into a subroutine call with source code that |
| 7056 | we should not step over. Do step to the first line of code in |
| 7057 | it. */ |
| 7058 | |
| 7059 | static void |
| 7060 | handle_step_into_function (struct gdbarch *gdbarch, |
| 7061 | struct execution_control_state *ecs) |
| 7062 | { |
| 7063 | struct compunit_symtab *cust; |
| 7064 | struct symtab_and_line stop_func_sal, sr_sal; |
| 7065 | |
| 7066 | fill_in_stop_func (gdbarch, ecs); |
| 7067 | |
| 7068 | cust = find_pc_compunit_symtab (stop_pc); |
| 7069 | if (cust != NULL && compunit_language (cust) != language_asm) |
| 7070 | ecs->stop_func_start = gdbarch_skip_prologue (gdbarch, |
| 7071 | ecs->stop_func_start); |
| 7072 | |
| 7073 | stop_func_sal = find_pc_line (ecs->stop_func_start, 0); |
| 7074 | /* Use the step_resume_break to step until the end of the prologue, |
| 7075 | even if that involves jumps (as it seems to on the vax under |
| 7076 | 4.2). */ |
| 7077 | /* If the prologue ends in the middle of a source line, continue to |
| 7078 | the end of that source line (if it is still within the function). |
| 7079 | Otherwise, just go to end of prologue. */ |
| 7080 | if (stop_func_sal.end |
| 7081 | && stop_func_sal.pc != ecs->stop_func_start |
| 7082 | && stop_func_sal.end < ecs->stop_func_end) |
| 7083 | ecs->stop_func_start = stop_func_sal.end; |
| 7084 | |
| 7085 | /* Architectures which require breakpoint adjustment might not be able |
| 7086 | to place a breakpoint at the computed address. If so, the test |
| 7087 | ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust |
| 7088 | ecs->stop_func_start to an address at which a breakpoint may be |
| 7089 | legitimately placed. |
| 7090 | |
| 7091 | Note: kevinb/2004-01-19: On FR-V, if this adjustment is not |
| 7092 | made, GDB will enter an infinite loop when stepping through |
| 7093 | optimized code consisting of VLIW instructions which contain |
| 7094 | subinstructions corresponding to different source lines. On |
| 7095 | FR-V, it's not permitted to place a breakpoint on any but the |
| 7096 | first subinstruction of a VLIW instruction. When a breakpoint is |
| 7097 | set, GDB will adjust the breakpoint address to the beginning of |
| 7098 | the VLIW instruction. Thus, we need to make the corresponding |
| 7099 | adjustment here when computing the stop address. */ |
| 7100 | |
| 7101 | if (gdbarch_adjust_breakpoint_address_p (gdbarch)) |
| 7102 | { |
| 7103 | ecs->stop_func_start |
| 7104 | = gdbarch_adjust_breakpoint_address (gdbarch, |
| 7105 | ecs->stop_func_start); |
| 7106 | } |
| 7107 | |
| 7108 | if (ecs->stop_func_start == stop_pc) |
| 7109 | { |
| 7110 | /* We are already there: stop now. */ |
| 7111 | end_stepping_range (ecs); |
| 7112 | return; |
| 7113 | } |
| 7114 | else |
| 7115 | { |
| 7116 | /* Put the step-breakpoint there and go until there. */ |
| 7117 | init_sal (&sr_sal); /* initialize to zeroes */ |
| 7118 | sr_sal.pc = ecs->stop_func_start; |
| 7119 | sr_sal.section = find_pc_overlay (ecs->stop_func_start); |
| 7120 | sr_sal.pspace = get_frame_program_space (get_current_frame ()); |
| 7121 | |
| 7122 | /* Do not specify what the fp should be when we stop since on |
| 7123 | some machines the prologue is where the new fp value is |
| 7124 | established. */ |
| 7125 | insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal, null_frame_id); |
| 7126 | |
| 7127 | /* And make sure stepping stops right away then. */ |
| 7128 | ecs->event_thread->control.step_range_end |
| 7129 | = ecs->event_thread->control.step_range_start; |
| 7130 | } |
| 7131 | keep_going (ecs); |
| 7132 | } |
| 7133 | |
| 7134 | /* Inferior has stepped backward into a subroutine call with source |
| 7135 | code that we should not step over. Do step to the beginning of the |
| 7136 | last line of code in it. */ |
| 7137 | |
| 7138 | static void |
| 7139 | handle_step_into_function_backward (struct gdbarch *gdbarch, |
| 7140 | struct execution_control_state *ecs) |
| 7141 | { |
| 7142 | struct compunit_symtab *cust; |
| 7143 | struct symtab_and_line stop_func_sal; |
| 7144 | |
| 7145 | fill_in_stop_func (gdbarch, ecs); |
| 7146 | |
| 7147 | cust = find_pc_compunit_symtab (stop_pc); |
| 7148 | if (cust != NULL && compunit_language (cust) != language_asm) |
| 7149 | ecs->stop_func_start = gdbarch_skip_prologue (gdbarch, |
| 7150 | ecs->stop_func_start); |
| 7151 | |
| 7152 | stop_func_sal = find_pc_line (stop_pc, 0); |
| 7153 | |
| 7154 | /* OK, we're just going to keep stepping here. */ |
| 7155 | if (stop_func_sal.pc == stop_pc) |
| 7156 | { |
| 7157 | /* We're there already. Just stop stepping now. */ |
| 7158 | end_stepping_range (ecs); |
| 7159 | } |
| 7160 | else |
| 7161 | { |
| 7162 | /* Else just reset the step range and keep going. |
| 7163 | No step-resume breakpoint, they don't work for |
| 7164 | epilogues, which can have multiple entry paths. */ |
| 7165 | ecs->event_thread->control.step_range_start = stop_func_sal.pc; |
| 7166 | ecs->event_thread->control.step_range_end = stop_func_sal.end; |
| 7167 | keep_going (ecs); |
| 7168 | } |
| 7169 | return; |
| 7170 | } |
| 7171 | |
| 7172 | /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID. |
| 7173 | This is used to both functions and to skip over code. */ |
| 7174 | |
| 7175 | static void |
| 7176 | insert_step_resume_breakpoint_at_sal_1 (struct gdbarch *gdbarch, |
| 7177 | struct symtab_and_line sr_sal, |
| 7178 | struct frame_id sr_id, |
| 7179 | enum bptype sr_type) |
| 7180 | { |
| 7181 | /* There should never be more than one step-resume or longjmp-resume |
| 7182 | breakpoint per thread, so we should never be setting a new |
| 7183 | step_resume_breakpoint when one is already active. */ |
| 7184 | gdb_assert (inferior_thread ()->control.step_resume_breakpoint == NULL); |
| 7185 | gdb_assert (sr_type == bp_step_resume || sr_type == bp_hp_step_resume); |
| 7186 | |
| 7187 | if (debug_infrun) |
| 7188 | fprintf_unfiltered (gdb_stdlog, |
| 7189 | "infrun: inserting step-resume breakpoint at %s\n", |
| 7190 | paddress (gdbarch, sr_sal.pc)); |
| 7191 | |
| 7192 | inferior_thread ()->control.step_resume_breakpoint |
| 7193 | = set_momentary_breakpoint (gdbarch, sr_sal, sr_id, sr_type); |
| 7194 | } |
| 7195 | |
| 7196 | void |
| 7197 | insert_step_resume_breakpoint_at_sal (struct gdbarch *gdbarch, |
| 7198 | struct symtab_and_line sr_sal, |
| 7199 | struct frame_id sr_id) |
| 7200 | { |
| 7201 | insert_step_resume_breakpoint_at_sal_1 (gdbarch, |
| 7202 | sr_sal, sr_id, |
| 7203 | bp_step_resume); |
| 7204 | } |
| 7205 | |
| 7206 | /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc. |
| 7207 | This is used to skip a potential signal handler. |
| 7208 | |
| 7209 | This is called with the interrupted function's frame. The signal |
| 7210 | handler, when it returns, will resume the interrupted function at |
| 7211 | RETURN_FRAME.pc. */ |
| 7212 | |
| 7213 | static void |
| 7214 | insert_hp_step_resume_breakpoint_at_frame (struct frame_info *return_frame) |
| 7215 | { |
| 7216 | struct symtab_and_line sr_sal; |
| 7217 | struct gdbarch *gdbarch; |
| 7218 | |
| 7219 | gdb_assert (return_frame != NULL); |
| 7220 | init_sal (&sr_sal); /* initialize to zeros */ |
| 7221 | |
| 7222 | gdbarch = get_frame_arch (return_frame); |
| 7223 | sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, get_frame_pc (return_frame)); |
| 7224 | sr_sal.section = find_pc_overlay (sr_sal.pc); |
| 7225 | sr_sal.pspace = get_frame_program_space (return_frame); |
| 7226 | |
| 7227 | insert_step_resume_breakpoint_at_sal_1 (gdbarch, sr_sal, |
| 7228 | get_stack_frame_id (return_frame), |
| 7229 | bp_hp_step_resume); |
| 7230 | } |
| 7231 | |
| 7232 | /* Insert a "step-resume breakpoint" at the previous frame's PC. This |
| 7233 | is used to skip a function after stepping into it (for "next" or if |
| 7234 | the called function has no debugging information). |
| 7235 | |
| 7236 | The current function has almost always been reached by single |
| 7237 | stepping a call or return instruction. NEXT_FRAME belongs to the |
| 7238 | current function, and the breakpoint will be set at the caller's |
| 7239 | resume address. |
| 7240 | |
| 7241 | This is a separate function rather than reusing |
| 7242 | insert_hp_step_resume_breakpoint_at_frame in order to avoid |
| 7243 | get_prev_frame, which may stop prematurely (see the implementation |
| 7244 | of frame_unwind_caller_id for an example). */ |
| 7245 | |
| 7246 | static void |
| 7247 | insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame) |
| 7248 | { |
| 7249 | struct symtab_and_line sr_sal; |
| 7250 | struct gdbarch *gdbarch; |
| 7251 | |
| 7252 | /* We shouldn't have gotten here if we don't know where the call site |
| 7253 | is. */ |
| 7254 | gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame))); |
| 7255 | |
| 7256 | init_sal (&sr_sal); /* initialize to zeros */ |
| 7257 | |
| 7258 | gdbarch = frame_unwind_caller_arch (next_frame); |
| 7259 | sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, |
| 7260 | frame_unwind_caller_pc (next_frame)); |
| 7261 | sr_sal.section = find_pc_overlay (sr_sal.pc); |
| 7262 | sr_sal.pspace = frame_unwind_program_space (next_frame); |
| 7263 | |
| 7264 | insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal, |
| 7265 | frame_unwind_caller_id (next_frame)); |
| 7266 | } |
| 7267 | |
| 7268 | /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a |
| 7269 | new breakpoint at the target of a jmp_buf. The handling of |
| 7270 | longjmp-resume uses the same mechanisms used for handling |
| 7271 | "step-resume" breakpoints. */ |
| 7272 | |
| 7273 | static void |
| 7274 | insert_longjmp_resume_breakpoint (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 7275 | { |
| 7276 | /* There should never be more than one longjmp-resume breakpoint per |
| 7277 | thread, so we should never be setting a new |
| 7278 | longjmp_resume_breakpoint when one is already active. */ |
| 7279 | gdb_assert (inferior_thread ()->control.exception_resume_breakpoint == NULL); |
| 7280 | |
| 7281 | if (debug_infrun) |
| 7282 | fprintf_unfiltered (gdb_stdlog, |
| 7283 | "infrun: inserting longjmp-resume breakpoint at %s\n", |
| 7284 | paddress (gdbarch, pc)); |
| 7285 | |
| 7286 | inferior_thread ()->control.exception_resume_breakpoint = |
| 7287 | set_momentary_breakpoint_at_pc (gdbarch, pc, bp_longjmp_resume); |
| 7288 | } |
| 7289 | |
| 7290 | /* Insert an exception resume breakpoint. TP is the thread throwing |
| 7291 | the exception. The block B is the block of the unwinder debug hook |
| 7292 | function. FRAME is the frame corresponding to the call to this |
| 7293 | function. SYM is the symbol of the function argument holding the |
| 7294 | target PC of the exception. */ |
| 7295 | |
| 7296 | static void |
| 7297 | insert_exception_resume_breakpoint (struct thread_info *tp, |
| 7298 | const struct block *b, |
| 7299 | struct frame_info *frame, |
| 7300 | struct symbol *sym) |
| 7301 | { |
| 7302 | TRY |
| 7303 | { |
| 7304 | struct block_symbol vsym; |
| 7305 | struct value *value; |
| 7306 | CORE_ADDR handler; |
| 7307 | struct breakpoint *bp; |
| 7308 | |
| 7309 | vsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym), b, VAR_DOMAIN, NULL); |
| 7310 | value = read_var_value (vsym.symbol, vsym.block, frame); |
| 7311 | /* If the value was optimized out, revert to the old behavior. */ |
| 7312 | if (! value_optimized_out (value)) |
| 7313 | { |
| 7314 | handler = value_as_address (value); |
| 7315 | |
| 7316 | if (debug_infrun) |
| 7317 | fprintf_unfiltered (gdb_stdlog, |
| 7318 | "infrun: exception resume at %lx\n", |
| 7319 | (unsigned long) handler); |
| 7320 | |
| 7321 | bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame), |
| 7322 | handler, bp_exception_resume); |
| 7323 | |
| 7324 | /* set_momentary_breakpoint_at_pc invalidates FRAME. */ |
| 7325 | frame = NULL; |
| 7326 | |
| 7327 | bp->thread = tp->num; |
| 7328 | inferior_thread ()->control.exception_resume_breakpoint = bp; |
| 7329 | } |
| 7330 | } |
| 7331 | CATCH (e, RETURN_MASK_ERROR) |
| 7332 | { |
| 7333 | /* We want to ignore errors here. */ |
| 7334 | } |
| 7335 | END_CATCH |
| 7336 | } |
| 7337 | |
| 7338 | /* A helper for check_exception_resume that sets an |
| 7339 | exception-breakpoint based on a SystemTap probe. */ |
| 7340 | |
| 7341 | static void |
| 7342 | insert_exception_resume_from_probe (struct thread_info *tp, |
| 7343 | const struct bound_probe *probe, |
| 7344 | struct frame_info *frame) |
| 7345 | { |
| 7346 | struct value *arg_value; |
| 7347 | CORE_ADDR handler; |
| 7348 | struct breakpoint *bp; |
| 7349 | |
| 7350 | arg_value = probe_safe_evaluate_at_pc (frame, 1); |
| 7351 | if (!arg_value) |
| 7352 | return; |
| 7353 | |
| 7354 | handler = value_as_address (arg_value); |
| 7355 | |
| 7356 | if (debug_infrun) |
| 7357 | fprintf_unfiltered (gdb_stdlog, |
| 7358 | "infrun: exception resume at %s\n", |
| 7359 | paddress (get_objfile_arch (probe->objfile), |
| 7360 | handler)); |
| 7361 | |
| 7362 | bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame), |
| 7363 | handler, bp_exception_resume); |
| 7364 | bp->thread = tp->num; |
| 7365 | inferior_thread ()->control.exception_resume_breakpoint = bp; |
| 7366 | } |
| 7367 | |
| 7368 | /* This is called when an exception has been intercepted. Check to |
| 7369 | see whether the exception's destination is of interest, and if so, |
| 7370 | set an exception resume breakpoint there. */ |
| 7371 | |
| 7372 | static void |
| 7373 | check_exception_resume (struct execution_control_state *ecs, |
| 7374 | struct frame_info *frame) |
| 7375 | { |
| 7376 | struct bound_probe probe; |
| 7377 | struct symbol *func; |
| 7378 | |
| 7379 | /* First see if this exception unwinding breakpoint was set via a |
| 7380 | SystemTap probe point. If so, the probe has two arguments: the |
| 7381 | CFA and the HANDLER. We ignore the CFA, extract the handler, and |
| 7382 | set a breakpoint there. */ |
| 7383 | probe = find_probe_by_pc (get_frame_pc (frame)); |
| 7384 | if (probe.probe) |
| 7385 | { |
| 7386 | insert_exception_resume_from_probe (ecs->event_thread, &probe, frame); |
| 7387 | return; |
| 7388 | } |
| 7389 | |
| 7390 | func = get_frame_function (frame); |
| 7391 | if (!func) |
| 7392 | return; |
| 7393 | |
| 7394 | TRY |
| 7395 | { |
| 7396 | const struct block *b; |
| 7397 | struct block_iterator iter; |
| 7398 | struct symbol *sym; |
| 7399 | int argno = 0; |
| 7400 | |
| 7401 | /* The exception breakpoint is a thread-specific breakpoint on |
| 7402 | the unwinder's debug hook, declared as: |
| 7403 | |
| 7404 | void _Unwind_DebugHook (void *cfa, void *handler); |
| 7405 | |
| 7406 | The CFA argument indicates the frame to which control is |
| 7407 | about to be transferred. HANDLER is the destination PC. |
| 7408 | |
| 7409 | We ignore the CFA and set a temporary breakpoint at HANDLER. |
| 7410 | This is not extremely efficient but it avoids issues in gdb |
| 7411 | with computing the DWARF CFA, and it also works even in weird |
| 7412 | cases such as throwing an exception from inside a signal |
| 7413 | handler. */ |
| 7414 | |
| 7415 | b = SYMBOL_BLOCK_VALUE (func); |
| 7416 | ALL_BLOCK_SYMBOLS (b, iter, sym) |
| 7417 | { |
| 7418 | if (!SYMBOL_IS_ARGUMENT (sym)) |
| 7419 | continue; |
| 7420 | |
| 7421 | if (argno == 0) |
| 7422 | ++argno; |
| 7423 | else |
| 7424 | { |
| 7425 | insert_exception_resume_breakpoint (ecs->event_thread, |
| 7426 | b, frame, sym); |
| 7427 | break; |
| 7428 | } |
| 7429 | } |
| 7430 | } |
| 7431 | CATCH (e, RETURN_MASK_ERROR) |
| 7432 | { |
| 7433 | } |
| 7434 | END_CATCH |
| 7435 | } |
| 7436 | |
| 7437 | static void |
| 7438 | stop_waiting (struct execution_control_state *ecs) |
| 7439 | { |
| 7440 | if (debug_infrun) |
| 7441 | fprintf_unfiltered (gdb_stdlog, "infrun: stop_waiting\n"); |
| 7442 | |
| 7443 | clear_step_over_info (); |
| 7444 | |
| 7445 | /* Let callers know we don't want to wait for the inferior anymore. */ |
| 7446 | ecs->wait_some_more = 0; |
| 7447 | |
| 7448 | /* If all-stop, but the target is always in non-stop mode, stop all |
| 7449 | threads now that we're presenting the stop to the user. */ |
| 7450 | if (!non_stop && target_is_non_stop_p ()) |
| 7451 | stop_all_threads (); |
| 7452 | } |
| 7453 | |
| 7454 | /* Like keep_going, but passes the signal to the inferior, even if the |
| 7455 | signal is set to nopass. */ |
| 7456 | |
| 7457 | static void |
| 7458 | keep_going_pass_signal (struct execution_control_state *ecs) |
| 7459 | { |
| 7460 | /* Make sure normal_stop is called if we get a QUIT handled before |
| 7461 | reaching resume. */ |
| 7462 | struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0); |
| 7463 | |
| 7464 | gdb_assert (ptid_equal (ecs->event_thread->ptid, inferior_ptid)); |
| 7465 | gdb_assert (!ecs->event_thread->resumed); |
| 7466 | |
| 7467 | /* Save the pc before execution, to compare with pc after stop. */ |
| 7468 | ecs->event_thread->prev_pc |
| 7469 | = regcache_read_pc (get_thread_regcache (ecs->ptid)); |
| 7470 | |
| 7471 | if (ecs->event_thread->control.trap_expected) |
| 7472 | { |
| 7473 | struct thread_info *tp = ecs->event_thread; |
| 7474 | |
| 7475 | if (debug_infrun) |
| 7476 | fprintf_unfiltered (gdb_stdlog, |
| 7477 | "infrun: %s has trap_expected set, " |
| 7478 | "resuming to collect trap\n", |
| 7479 | target_pid_to_str (tp->ptid)); |
| 7480 | |
| 7481 | /* We haven't yet gotten our trap, and either: intercepted a |
| 7482 | non-signal event (e.g., a fork); or took a signal which we |
| 7483 | are supposed to pass through to the inferior. Simply |
| 7484 | continue. */ |
| 7485 | discard_cleanups (old_cleanups); |
| 7486 | resume (ecs->event_thread->suspend.stop_signal); |
| 7487 | } |
| 7488 | else if (step_over_info_valid_p ()) |
| 7489 | { |
| 7490 | /* Another thread is stepping over a breakpoint in-line. If |
| 7491 | this thread needs a step-over too, queue the request. In |
| 7492 | either case, this resume must be deferred for later. */ |
| 7493 | struct thread_info *tp = ecs->event_thread; |
| 7494 | |
| 7495 | if (ecs->hit_singlestep_breakpoint |
| 7496 | || thread_still_needs_step_over (tp)) |
| 7497 | { |
| 7498 | if (debug_infrun) |
| 7499 | fprintf_unfiltered (gdb_stdlog, |
| 7500 | "infrun: step-over already in progress: " |
| 7501 | "step-over for %s deferred\n", |
| 7502 | target_pid_to_str (tp->ptid)); |
| 7503 | thread_step_over_chain_enqueue (tp); |
| 7504 | } |
| 7505 | else |
| 7506 | { |
| 7507 | if (debug_infrun) |
| 7508 | fprintf_unfiltered (gdb_stdlog, |
| 7509 | "infrun: step-over in progress: " |
| 7510 | "resume of %s deferred\n", |
| 7511 | target_pid_to_str (tp->ptid)); |
| 7512 | } |
| 7513 | |
| 7514 | discard_cleanups (old_cleanups); |
| 7515 | } |
| 7516 | else |
| 7517 | { |
| 7518 | struct regcache *regcache = get_current_regcache (); |
| 7519 | int remove_bp; |
| 7520 | int remove_wps; |
| 7521 | enum step_over_what step_what; |
| 7522 | |
| 7523 | /* Either the trap was not expected, but we are continuing |
| 7524 | anyway (if we got a signal, the user asked it be passed to |
| 7525 | the child) |
| 7526 | -- or -- |
| 7527 | We got our expected trap, but decided we should resume from |
| 7528 | it. |
| 7529 | |
| 7530 | We're going to run this baby now! |
| 7531 | |
| 7532 | Note that insert_breakpoints won't try to re-insert |
| 7533 | already inserted breakpoints. Therefore, we don't |
| 7534 | care if breakpoints were already inserted, or not. */ |
| 7535 | |
| 7536 | /* If we need to step over a breakpoint, and we're not using |
| 7537 | displaced stepping to do so, insert all breakpoints |
| 7538 | (watchpoints, etc.) but the one we're stepping over, step one |
| 7539 | instruction, and then re-insert the breakpoint when that step |
| 7540 | is finished. */ |
| 7541 | |
| 7542 | step_what = thread_still_needs_step_over (ecs->event_thread); |
| 7543 | |
| 7544 | remove_bp = (ecs->hit_singlestep_breakpoint |
| 7545 | || (step_what & STEP_OVER_BREAKPOINT)); |
| 7546 | remove_wps = (step_what & STEP_OVER_WATCHPOINT); |
| 7547 | |
| 7548 | /* We can't use displaced stepping if we need to step past a |
| 7549 | watchpoint. The instruction copied to the scratch pad would |
| 7550 | still trigger the watchpoint. */ |
| 7551 | if (remove_bp |
| 7552 | && (remove_wps || !use_displaced_stepping (ecs->event_thread))) |
| 7553 | { |
| 7554 | set_step_over_info (get_regcache_aspace (regcache), |
| 7555 | regcache_read_pc (regcache), remove_wps); |
| 7556 | } |
| 7557 | else if (remove_wps) |
| 7558 | set_step_over_info (NULL, 0, remove_wps); |
| 7559 | |
| 7560 | /* If we now need to do an in-line step-over, we need to stop |
| 7561 | all other threads. Note this must be done before |
| 7562 | insert_breakpoints below, because that removes the breakpoint |
| 7563 | we're about to step over, otherwise other threads could miss |
| 7564 | it. */ |
| 7565 | if (step_over_info_valid_p () && target_is_non_stop_p ()) |
| 7566 | stop_all_threads (); |
| 7567 | |
| 7568 | /* Stop stepping if inserting breakpoints fails. */ |
| 7569 | TRY |
| 7570 | { |
| 7571 | insert_breakpoints (); |
| 7572 | } |
| 7573 | CATCH (e, RETURN_MASK_ERROR) |
| 7574 | { |
| 7575 | exception_print (gdb_stderr, e); |
| 7576 | stop_waiting (ecs); |
| 7577 | discard_cleanups (old_cleanups); |
| 7578 | return; |
| 7579 | } |
| 7580 | END_CATCH |
| 7581 | |
| 7582 | ecs->event_thread->control.trap_expected = (remove_bp || remove_wps); |
| 7583 | |
| 7584 | discard_cleanups (old_cleanups); |
| 7585 | resume (ecs->event_thread->suspend.stop_signal); |
| 7586 | } |
| 7587 | |
| 7588 | prepare_to_wait (ecs); |
| 7589 | } |
| 7590 | |
| 7591 | /* Called when we should continue running the inferior, because the |
| 7592 | current event doesn't cause a user visible stop. This does the |
| 7593 | resuming part; waiting for the next event is done elsewhere. */ |
| 7594 | |
| 7595 | static void |
| 7596 | keep_going (struct execution_control_state *ecs) |
| 7597 | { |
| 7598 | if (ecs->event_thread->control.trap_expected |
| 7599 | && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP) |
| 7600 | ecs->event_thread->control.trap_expected = 0; |
| 7601 | |
| 7602 | if (!signal_program[ecs->event_thread->suspend.stop_signal]) |
| 7603 | ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0; |
| 7604 | keep_going_pass_signal (ecs); |
| 7605 | } |
| 7606 | |
| 7607 | /* This function normally comes after a resume, before |
| 7608 | handle_inferior_event exits. It takes care of any last bits of |
| 7609 | housekeeping, and sets the all-important wait_some_more flag. */ |
| 7610 | |
| 7611 | static void |
| 7612 | prepare_to_wait (struct execution_control_state *ecs) |
| 7613 | { |
| 7614 | if (debug_infrun) |
| 7615 | fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n"); |
| 7616 | |
| 7617 | ecs->wait_some_more = 1; |
| 7618 | |
| 7619 | if (!target_is_async_p ()) |
| 7620 | mark_infrun_async_event_handler (); |
| 7621 | } |
| 7622 | |
| 7623 | /* We are done with the step range of a step/next/si/ni command. |
| 7624 | Called once for each n of a "step n" operation. */ |
| 7625 | |
| 7626 | static void |
| 7627 | end_stepping_range (struct execution_control_state *ecs) |
| 7628 | { |
| 7629 | ecs->event_thread->control.stop_step = 1; |
| 7630 | stop_waiting (ecs); |
| 7631 | } |
| 7632 | |
| 7633 | /* Several print_*_reason functions to print why the inferior has stopped. |
| 7634 | We always print something when the inferior exits, or receives a signal. |
| 7635 | The rest of the cases are dealt with later on in normal_stop and |
| 7636 | print_it_typical. Ideally there should be a call to one of these |
| 7637 | print_*_reason functions functions from handle_inferior_event each time |
| 7638 | stop_waiting is called. |
| 7639 | |
| 7640 | Note that we don't call these directly, instead we delegate that to |
| 7641 | the interpreters, through observers. Interpreters then call these |
| 7642 | with whatever uiout is right. */ |
| 7643 | |
| 7644 | void |
| 7645 | print_end_stepping_range_reason (struct ui_out *uiout) |
| 7646 | { |
| 7647 | /* For CLI-like interpreters, print nothing. */ |
| 7648 | |
| 7649 | if (ui_out_is_mi_like_p (uiout)) |
| 7650 | { |
| 7651 | ui_out_field_string (uiout, "reason", |
| 7652 | async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE)); |
| 7653 | } |
| 7654 | } |
| 7655 | |
| 7656 | void |
| 7657 | print_signal_exited_reason (struct ui_out *uiout, enum gdb_signal siggnal) |
| 7658 | { |
| 7659 | annotate_signalled (); |
| 7660 | if (ui_out_is_mi_like_p (uiout)) |
| 7661 | ui_out_field_string |
| 7662 | (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED)); |
| 7663 | ui_out_text (uiout, "\nProgram terminated with signal "); |
| 7664 | annotate_signal_name (); |
| 7665 | ui_out_field_string (uiout, "signal-name", |
| 7666 | gdb_signal_to_name (siggnal)); |
| 7667 | annotate_signal_name_end (); |
| 7668 | ui_out_text (uiout, ", "); |
| 7669 | annotate_signal_string (); |
| 7670 | ui_out_field_string (uiout, "signal-meaning", |
| 7671 | gdb_signal_to_string (siggnal)); |
| 7672 | annotate_signal_string_end (); |
| 7673 | ui_out_text (uiout, ".\n"); |
| 7674 | ui_out_text (uiout, "The program no longer exists.\n"); |
| 7675 | } |
| 7676 | |
| 7677 | void |
| 7678 | print_exited_reason (struct ui_out *uiout, int exitstatus) |
| 7679 | { |
| 7680 | struct inferior *inf = current_inferior (); |
| 7681 | const char *pidstr = target_pid_to_str (pid_to_ptid (inf->pid)); |
| 7682 | |
| 7683 | annotate_exited (exitstatus); |
| 7684 | if (exitstatus) |
| 7685 | { |
| 7686 | if (ui_out_is_mi_like_p (uiout)) |
| 7687 | ui_out_field_string (uiout, "reason", |
| 7688 | async_reason_lookup (EXEC_ASYNC_EXITED)); |
| 7689 | ui_out_text (uiout, "[Inferior "); |
| 7690 | ui_out_text (uiout, plongest (inf->num)); |
| 7691 | ui_out_text (uiout, " ("); |
| 7692 | ui_out_text (uiout, pidstr); |
| 7693 | ui_out_text (uiout, ") exited with code "); |
| 7694 | ui_out_field_fmt (uiout, "exit-code", "0%o", (unsigned int) exitstatus); |
| 7695 | ui_out_text (uiout, "]\n"); |
| 7696 | } |
| 7697 | else |
| 7698 | { |
| 7699 | if (ui_out_is_mi_like_p (uiout)) |
| 7700 | ui_out_field_string |
| 7701 | (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY)); |
| 7702 | ui_out_text (uiout, "[Inferior "); |
| 7703 | ui_out_text (uiout, plongest (inf->num)); |
| 7704 | ui_out_text (uiout, " ("); |
| 7705 | ui_out_text (uiout, pidstr); |
| 7706 | ui_out_text (uiout, ") exited normally]\n"); |
| 7707 | } |
| 7708 | } |
| 7709 | |
| 7710 | void |
| 7711 | print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal) |
| 7712 | { |
| 7713 | annotate_signal (); |
| 7714 | |
| 7715 | if (siggnal == GDB_SIGNAL_0 && !ui_out_is_mi_like_p (uiout)) |
| 7716 | { |
| 7717 | struct thread_info *t = inferior_thread (); |
| 7718 | |
| 7719 | ui_out_text (uiout, "\n["); |
| 7720 | ui_out_field_string (uiout, "thread-name", |
| 7721 | target_pid_to_str (t->ptid)); |
| 7722 | ui_out_field_fmt (uiout, "thread-id", "] #%d", t->num); |
| 7723 | ui_out_text (uiout, " stopped"); |
| 7724 | } |
| 7725 | else |
| 7726 | { |
| 7727 | ui_out_text (uiout, "\nProgram received signal "); |
| 7728 | annotate_signal_name (); |
| 7729 | if (ui_out_is_mi_like_p (uiout)) |
| 7730 | ui_out_field_string |
| 7731 | (uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED)); |
| 7732 | ui_out_field_string (uiout, "signal-name", |
| 7733 | gdb_signal_to_name (siggnal)); |
| 7734 | annotate_signal_name_end (); |
| 7735 | ui_out_text (uiout, ", "); |
| 7736 | annotate_signal_string (); |
| 7737 | ui_out_field_string (uiout, "signal-meaning", |
| 7738 | gdb_signal_to_string (siggnal)); |
| 7739 | annotate_signal_string_end (); |
| 7740 | } |
| 7741 | ui_out_text (uiout, ".\n"); |
| 7742 | } |
| 7743 | |
| 7744 | void |
| 7745 | print_no_history_reason (struct ui_out *uiout) |
| 7746 | { |
| 7747 | ui_out_text (uiout, "\nNo more reverse-execution history.\n"); |
| 7748 | } |
| 7749 | |
| 7750 | /* Print current location without a level number, if we have changed |
| 7751 | functions or hit a breakpoint. Print source line if we have one. |
| 7752 | bpstat_print contains the logic deciding in detail what to print, |
| 7753 | based on the event(s) that just occurred. */ |
| 7754 | |
| 7755 | static void |
| 7756 | print_stop_location (struct target_waitstatus *ws) |
| 7757 | { |
| 7758 | int bpstat_ret; |
| 7759 | enum print_what source_flag; |
| 7760 | int do_frame_printing = 1; |
| 7761 | struct thread_info *tp = inferior_thread (); |
| 7762 | |
| 7763 | bpstat_ret = bpstat_print (tp->control.stop_bpstat, ws->kind); |
| 7764 | switch (bpstat_ret) |
| 7765 | { |
| 7766 | case PRINT_UNKNOWN: |
| 7767 | /* FIXME: cagney/2002-12-01: Given that a frame ID does (or |
| 7768 | should) carry around the function and does (or should) use |
| 7769 | that when doing a frame comparison. */ |
| 7770 | if (tp->control.stop_step |
| 7771 | && frame_id_eq (tp->control.step_frame_id, |
| 7772 | get_frame_id (get_current_frame ())) |
| 7773 | && tp->control.step_start_function == find_pc_function (stop_pc)) |
| 7774 | { |
| 7775 | /* Finished step, just print source line. */ |
| 7776 | source_flag = SRC_LINE; |
| 7777 | } |
| 7778 | else |
| 7779 | { |
| 7780 | /* Print location and source line. */ |
| 7781 | source_flag = SRC_AND_LOC; |
| 7782 | } |
| 7783 | break; |
| 7784 | case PRINT_SRC_AND_LOC: |
| 7785 | /* Print location and source line. */ |
| 7786 | source_flag = SRC_AND_LOC; |
| 7787 | break; |
| 7788 | case PRINT_SRC_ONLY: |
| 7789 | source_flag = SRC_LINE; |
| 7790 | break; |
| 7791 | case PRINT_NOTHING: |
| 7792 | /* Something bogus. */ |
| 7793 | source_flag = SRC_LINE; |
| 7794 | do_frame_printing = 0; |
| 7795 | break; |
| 7796 | default: |
| 7797 | internal_error (__FILE__, __LINE__, _("Unknown value.")); |
| 7798 | } |
| 7799 | |
| 7800 | /* The behavior of this routine with respect to the source |
| 7801 | flag is: |
| 7802 | SRC_LINE: Print only source line |
| 7803 | LOCATION: Print only location |
| 7804 | SRC_AND_LOC: Print location and source line. */ |
| 7805 | if (do_frame_printing) |
| 7806 | print_stack_frame (get_selected_frame (NULL), 0, source_flag, 1); |
| 7807 | } |
| 7808 | |
| 7809 | /* Cleanup that restores a previous current uiout. */ |
| 7810 | |
| 7811 | static void |
| 7812 | restore_current_uiout_cleanup (void *arg) |
| 7813 | { |
| 7814 | struct ui_out *saved_uiout = arg; |
| 7815 | |
| 7816 | current_uiout = saved_uiout; |
| 7817 | } |
| 7818 | |
| 7819 | /* See infrun.h. */ |
| 7820 | |
| 7821 | void |
| 7822 | print_stop_event (struct ui_out *uiout) |
| 7823 | { |
| 7824 | struct cleanup *old_chain; |
| 7825 | struct target_waitstatus last; |
| 7826 | ptid_t last_ptid; |
| 7827 | struct thread_info *tp; |
| 7828 | |
| 7829 | get_last_target_status (&last_ptid, &last); |
| 7830 | |
| 7831 | old_chain = make_cleanup (restore_current_uiout_cleanup, current_uiout); |
| 7832 | current_uiout = uiout; |
| 7833 | |
| 7834 | print_stop_location (&last); |
| 7835 | |
| 7836 | /* Display the auto-display expressions. */ |
| 7837 | do_displays (); |
| 7838 | |
| 7839 | do_cleanups (old_chain); |
| 7840 | |
| 7841 | tp = inferior_thread (); |
| 7842 | if (tp->thread_fsm != NULL |
| 7843 | && thread_fsm_finished_p (tp->thread_fsm)) |
| 7844 | { |
| 7845 | struct return_value_info *rv; |
| 7846 | |
| 7847 | rv = thread_fsm_return_value (tp->thread_fsm); |
| 7848 | if (rv != NULL) |
| 7849 | print_return_value (uiout, rv); |
| 7850 | } |
| 7851 | } |
| 7852 | |
| 7853 | /* See infrun.h. */ |
| 7854 | |
| 7855 | void |
| 7856 | maybe_remove_breakpoints (void) |
| 7857 | { |
| 7858 | if (!breakpoints_should_be_inserted_now () && target_has_execution) |
| 7859 | { |
| 7860 | if (remove_breakpoints ()) |
| 7861 | { |
| 7862 | target_terminal_ours_for_output (); |
| 7863 | printf_filtered (_("Cannot remove breakpoints because " |
| 7864 | "program is no longer writable.\nFurther " |
| 7865 | "execution is probably impossible.\n")); |
| 7866 | } |
| 7867 | } |
| 7868 | } |
| 7869 | |
| 7870 | /* The execution context that just caused a normal stop. */ |
| 7871 | |
| 7872 | struct stop_context |
| 7873 | { |
| 7874 | /* The stop ID. */ |
| 7875 | ULONGEST stop_id; |
| 7876 | |
| 7877 | /* The event PTID. */ |
| 7878 | |
| 7879 | ptid_t ptid; |
| 7880 | |
| 7881 | /* If stopp for a thread event, this is the thread that caused the |
| 7882 | stop. */ |
| 7883 | struct thread_info *thread; |
| 7884 | |
| 7885 | /* The inferior that caused the stop. */ |
| 7886 | int inf_num; |
| 7887 | }; |
| 7888 | |
| 7889 | /* Returns a new stop context. If stopped for a thread event, this |
| 7890 | takes a strong reference to the thread. */ |
| 7891 | |
| 7892 | static struct stop_context * |
| 7893 | save_stop_context (void) |
| 7894 | { |
| 7895 | struct stop_context *sc = xmalloc (sizeof (struct stop_context)); |
| 7896 | |
| 7897 | sc->stop_id = get_stop_id (); |
| 7898 | sc->ptid = inferior_ptid; |
| 7899 | sc->inf_num = current_inferior ()->num; |
| 7900 | |
| 7901 | if (!ptid_equal (inferior_ptid, null_ptid)) |
| 7902 | { |
| 7903 | /* Take a strong reference so that the thread can't be deleted |
| 7904 | yet. */ |
| 7905 | sc->thread = inferior_thread (); |
| 7906 | sc->thread->refcount++; |
| 7907 | } |
| 7908 | else |
| 7909 | sc->thread = NULL; |
| 7910 | |
| 7911 | return sc; |
| 7912 | } |
| 7913 | |
| 7914 | /* Release a stop context previously created with save_stop_context. |
| 7915 | Releases the strong reference to the thread as well. */ |
| 7916 | |
| 7917 | static void |
| 7918 | release_stop_context_cleanup (void *arg) |
| 7919 | { |
| 7920 | struct stop_context *sc = arg; |
| 7921 | |
| 7922 | if (sc->thread != NULL) |
| 7923 | sc->thread->refcount--; |
| 7924 | xfree (sc); |
| 7925 | } |
| 7926 | |
| 7927 | /* Return true if the current context no longer matches the saved stop |
| 7928 | context. */ |
| 7929 | |
| 7930 | static int |
| 7931 | stop_context_changed (struct stop_context *prev) |
| 7932 | { |
| 7933 | if (!ptid_equal (prev->ptid, inferior_ptid)) |
| 7934 | return 1; |
| 7935 | if (prev->inf_num != current_inferior ()->num) |
| 7936 | return 1; |
| 7937 | if (prev->thread != NULL && prev->thread->state != THREAD_STOPPED) |
| 7938 | return 1; |
| 7939 | if (get_stop_id () != prev->stop_id) |
| 7940 | return 1; |
| 7941 | return 0; |
| 7942 | } |
| 7943 | |
| 7944 | /* See infrun.h. */ |
| 7945 | |
| 7946 | int |
| 7947 | normal_stop (void) |
| 7948 | { |
| 7949 | struct target_waitstatus last; |
| 7950 | ptid_t last_ptid; |
| 7951 | struct cleanup *old_chain = make_cleanup (null_cleanup, NULL); |
| 7952 | ptid_t pid_ptid; |
| 7953 | |
| 7954 | get_last_target_status (&last_ptid, &last); |
| 7955 | |
| 7956 | new_stop_id (); |
| 7957 | |
| 7958 | /* If an exception is thrown from this point on, make sure to |
| 7959 | propagate GDB's knowledge of the executing state to the |
| 7960 | frontend/user running state. A QUIT is an easy exception to see |
| 7961 | here, so do this before any filtered output. */ |
| 7962 | if (!non_stop) |
| 7963 | make_cleanup (finish_thread_state_cleanup, &minus_one_ptid); |
| 7964 | else if (last.kind == TARGET_WAITKIND_SIGNALLED |
| 7965 | || last.kind == TARGET_WAITKIND_EXITED) |
| 7966 | { |
| 7967 | /* On some targets, we may still have live threads in the |
| 7968 | inferior when we get a process exit event. E.g., for |
| 7969 | "checkpoint", when the current checkpoint/fork exits, |
| 7970 | linux-fork.c automatically switches to another fork from |
| 7971 | within target_mourn_inferior. */ |
| 7972 | if (!ptid_equal (inferior_ptid, null_ptid)) |
| 7973 | { |
| 7974 | pid_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid)); |
| 7975 | make_cleanup (finish_thread_state_cleanup, &pid_ptid); |
| 7976 | } |
| 7977 | } |
| 7978 | else if (last.kind != TARGET_WAITKIND_NO_RESUMED) |
| 7979 | make_cleanup (finish_thread_state_cleanup, &inferior_ptid); |
| 7980 | |
| 7981 | /* As we're presenting a stop, and potentially removing breakpoints, |
| 7982 | update the thread list so we can tell whether there are threads |
| 7983 | running on the target. With target remote, for example, we can |
| 7984 | only learn about new threads when we explicitly update the thread |
| 7985 | list. Do this before notifying the interpreters about signal |
| 7986 | stops, end of stepping ranges, etc., so that the "new thread" |
| 7987 | output is emitted before e.g., "Program received signal FOO", |
| 7988 | instead of after. */ |
| 7989 | update_thread_list (); |
| 7990 | |
| 7991 | if (last.kind == TARGET_WAITKIND_STOPPED && stopped_by_random_signal) |
| 7992 | observer_notify_signal_received (inferior_thread ()->suspend.stop_signal); |
| 7993 | |
| 7994 | /* As with the notification of thread events, we want to delay |
| 7995 | notifying the user that we've switched thread context until |
| 7996 | the inferior actually stops. |
| 7997 | |
| 7998 | There's no point in saying anything if the inferior has exited. |
| 7999 | Note that SIGNALLED here means "exited with a signal", not |
| 8000 | "received a signal". |
| 8001 | |
| 8002 | Also skip saying anything in non-stop mode. In that mode, as we |
| 8003 | don't want GDB to switch threads behind the user's back, to avoid |
| 8004 | races where the user is typing a command to apply to thread x, |
| 8005 | but GDB switches to thread y before the user finishes entering |
| 8006 | the command, fetch_inferior_event installs a cleanup to restore |
| 8007 | the current thread back to the thread the user had selected right |
| 8008 | after this event is handled, so we're not really switching, only |
| 8009 | informing of a stop. */ |
| 8010 | if (!non_stop |
| 8011 | && !ptid_equal (previous_inferior_ptid, inferior_ptid) |
| 8012 | && target_has_execution |
| 8013 | && last.kind != TARGET_WAITKIND_SIGNALLED |
| 8014 | && last.kind != TARGET_WAITKIND_EXITED |
| 8015 | && last.kind != TARGET_WAITKIND_NO_RESUMED) |
| 8016 | { |
| 8017 | target_terminal_ours_for_output (); |
| 8018 | printf_filtered (_("[Switching to %s]\n"), |
| 8019 | target_pid_to_str (inferior_ptid)); |
| 8020 | annotate_thread_changed (); |
| 8021 | previous_inferior_ptid = inferior_ptid; |
| 8022 | } |
| 8023 | |
| 8024 | if (last.kind == TARGET_WAITKIND_NO_RESUMED) |
| 8025 | { |
| 8026 | gdb_assert (sync_execution || !target_can_async_p ()); |
| 8027 | |
| 8028 | target_terminal_ours_for_output (); |
| 8029 | printf_filtered (_("No unwaited-for children left.\n")); |
| 8030 | } |
| 8031 | |
| 8032 | /* Note: this depends on the update_thread_list call above. */ |
| 8033 | maybe_remove_breakpoints (); |
| 8034 | |
| 8035 | /* If an auto-display called a function and that got a signal, |
| 8036 | delete that auto-display to avoid an infinite recursion. */ |
| 8037 | |
| 8038 | if (stopped_by_random_signal) |
| 8039 | disable_current_display (); |
| 8040 | |
| 8041 | target_terminal_ours (); |
| 8042 | async_enable_stdin (); |
| 8043 | |
| 8044 | /* Let the user/frontend see the threads as stopped. */ |
| 8045 | do_cleanups (old_chain); |
| 8046 | |
| 8047 | /* Select innermost stack frame - i.e., current frame is frame 0, |
| 8048 | and current location is based on that. Handle the case where the |
| 8049 | dummy call is returning after being stopped. E.g. the dummy call |
| 8050 | previously hit a breakpoint. (If the dummy call returns |
| 8051 | normally, we won't reach here.) Do this before the stop hook is |
| 8052 | run, so that it doesn't get to see the temporary dummy frame, |
| 8053 | which is not where we'll present the stop. */ |
| 8054 | if (has_stack_frames ()) |
| 8055 | { |
| 8056 | if (stop_stack_dummy == STOP_STACK_DUMMY) |
| 8057 | { |
| 8058 | /* Pop the empty frame that contains the stack dummy. This |
| 8059 | also restores inferior state prior to the call (struct |
| 8060 | infcall_suspend_state). */ |
| 8061 | struct frame_info *frame = get_current_frame (); |
| 8062 | |
| 8063 | gdb_assert (get_frame_type (frame) == DUMMY_FRAME); |
| 8064 | frame_pop (frame); |
| 8065 | /* frame_pop calls reinit_frame_cache as the last thing it |
| 8066 | does which means there's now no selected frame. */ |
| 8067 | } |
| 8068 | |
| 8069 | select_frame (get_current_frame ()); |
| 8070 | |
| 8071 | /* Set the current source location. */ |
| 8072 | set_current_sal_from_frame (get_current_frame ()); |
| 8073 | } |
| 8074 | |
| 8075 | /* Look up the hook_stop and run it (CLI internally handles problem |
| 8076 | of stop_command's pre-hook not existing). */ |
| 8077 | if (stop_command != NULL) |
| 8078 | { |
| 8079 | struct stop_context *saved_context = save_stop_context (); |
| 8080 | struct cleanup *old_chain |
| 8081 | = make_cleanup (release_stop_context_cleanup, saved_context); |
| 8082 | |
| 8083 | catch_errors (hook_stop_stub, stop_command, |
| 8084 | "Error while running hook_stop:\n", RETURN_MASK_ALL); |
| 8085 | |
| 8086 | /* If the stop hook resumes the target, then there's no point in |
| 8087 | trying to notify about the previous stop; its context is |
| 8088 | gone. Likewise if the command switches thread or inferior -- |
| 8089 | the observers would print a stop for the wrong |
| 8090 | thread/inferior. */ |
| 8091 | if (stop_context_changed (saved_context)) |
| 8092 | { |
| 8093 | do_cleanups (old_chain); |
| 8094 | return 1; |
| 8095 | } |
| 8096 | do_cleanups (old_chain); |
| 8097 | } |
| 8098 | |
| 8099 | /* Notify observers about the stop. This is where the interpreters |
| 8100 | print the stop event. */ |
| 8101 | if (!ptid_equal (inferior_ptid, null_ptid)) |
| 8102 | observer_notify_normal_stop (inferior_thread ()->control.stop_bpstat, |
| 8103 | stop_print_frame); |
| 8104 | else |
| 8105 | observer_notify_normal_stop (NULL, stop_print_frame); |
| 8106 | |
| 8107 | annotate_stopped (); |
| 8108 | |
| 8109 | if (target_has_execution) |
| 8110 | { |
| 8111 | if (last.kind != TARGET_WAITKIND_SIGNALLED |
| 8112 | && last.kind != TARGET_WAITKIND_EXITED) |
| 8113 | /* Delete the breakpoint we stopped at, if it wants to be deleted. |
| 8114 | Delete any breakpoint that is to be deleted at the next stop. */ |
| 8115 | breakpoint_auto_delete (inferior_thread ()->control.stop_bpstat); |
| 8116 | } |
| 8117 | |
| 8118 | /* Try to get rid of automatically added inferiors that are no |
| 8119 | longer needed. Keeping those around slows down things linearly. |
| 8120 | Note that this never removes the current inferior. */ |
| 8121 | prune_inferiors (); |
| 8122 | |
| 8123 | return 0; |
| 8124 | } |
| 8125 | |
| 8126 | static int |
| 8127 | hook_stop_stub (void *cmd) |
| 8128 | { |
| 8129 | execute_cmd_pre_hook ((struct cmd_list_element *) cmd); |
| 8130 | return (0); |
| 8131 | } |
| 8132 | \f |
| 8133 | int |
| 8134 | signal_stop_state (int signo) |
| 8135 | { |
| 8136 | return signal_stop[signo]; |
| 8137 | } |
| 8138 | |
| 8139 | int |
| 8140 | signal_print_state (int signo) |
| 8141 | { |
| 8142 | return signal_print[signo]; |
| 8143 | } |
| 8144 | |
| 8145 | int |
| 8146 | signal_pass_state (int signo) |
| 8147 | { |
| 8148 | return signal_program[signo]; |
| 8149 | } |
| 8150 | |
| 8151 | static void |
| 8152 | signal_cache_update (int signo) |
| 8153 | { |
| 8154 | if (signo == -1) |
| 8155 | { |
| 8156 | for (signo = 0; signo < (int) GDB_SIGNAL_LAST; signo++) |
| 8157 | signal_cache_update (signo); |
| 8158 | |
| 8159 | return; |
| 8160 | } |
| 8161 | |
| 8162 | signal_pass[signo] = (signal_stop[signo] == 0 |
| 8163 | && signal_print[signo] == 0 |
| 8164 | && signal_program[signo] == 1 |
| 8165 | && signal_catch[signo] == 0); |
| 8166 | } |
| 8167 | |
| 8168 | int |
| 8169 | signal_stop_update (int signo, int state) |
| 8170 | { |
| 8171 | int ret = signal_stop[signo]; |
| 8172 | |
| 8173 | signal_stop[signo] = state; |
| 8174 | signal_cache_update (signo); |
| 8175 | return ret; |
| 8176 | } |
| 8177 | |
| 8178 | int |
| 8179 | signal_print_update (int signo, int state) |
| 8180 | { |
| 8181 | int ret = signal_print[signo]; |
| 8182 | |
| 8183 | signal_print[signo] = state; |
| 8184 | signal_cache_update (signo); |
| 8185 | return ret; |
| 8186 | } |
| 8187 | |
| 8188 | int |
| 8189 | signal_pass_update (int signo, int state) |
| 8190 | { |
| 8191 | int ret = signal_program[signo]; |
| 8192 | |
| 8193 | signal_program[signo] = state; |
| 8194 | signal_cache_update (signo); |
| 8195 | return ret; |
| 8196 | } |
| 8197 | |
| 8198 | /* Update the global 'signal_catch' from INFO and notify the |
| 8199 | target. */ |
| 8200 | |
| 8201 | void |
| 8202 | signal_catch_update (const unsigned int *info) |
| 8203 | { |
| 8204 | int i; |
| 8205 | |
| 8206 | for (i = 0; i < GDB_SIGNAL_LAST; ++i) |
| 8207 | signal_catch[i] = info[i] > 0; |
| 8208 | signal_cache_update (-1); |
| 8209 | target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass); |
| 8210 | } |
| 8211 | |
| 8212 | static void |
| 8213 | sig_print_header (void) |
| 8214 | { |
| 8215 | printf_filtered (_("Signal Stop\tPrint\tPass " |
| 8216 | "to program\tDescription\n")); |
| 8217 | } |
| 8218 | |
| 8219 | static void |
| 8220 | sig_print_info (enum gdb_signal oursig) |
| 8221 | { |
| 8222 | const char *name = gdb_signal_to_name (oursig); |
| 8223 | int name_padding = 13 - strlen (name); |
| 8224 | |
| 8225 | if (name_padding <= 0) |
| 8226 | name_padding = 0; |
| 8227 | |
| 8228 | printf_filtered ("%s", name); |
| 8229 | printf_filtered ("%*.*s ", name_padding, name_padding, " "); |
| 8230 | printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No"); |
| 8231 | printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No"); |
| 8232 | printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No"); |
| 8233 | printf_filtered ("%s\n", gdb_signal_to_string (oursig)); |
| 8234 | } |
| 8235 | |
| 8236 | /* Specify how various signals in the inferior should be handled. */ |
| 8237 | |
| 8238 | static void |
| 8239 | handle_command (char *args, int from_tty) |
| 8240 | { |
| 8241 | char **argv; |
| 8242 | int digits, wordlen; |
| 8243 | int sigfirst, signum, siglast; |
| 8244 | enum gdb_signal oursig; |
| 8245 | int allsigs; |
| 8246 | int nsigs; |
| 8247 | unsigned char *sigs; |
| 8248 | struct cleanup *old_chain; |
| 8249 | |
| 8250 | if (args == NULL) |
| 8251 | { |
| 8252 | error_no_arg (_("signal to handle")); |
| 8253 | } |
| 8254 | |
| 8255 | /* Allocate and zero an array of flags for which signals to handle. */ |
| 8256 | |
| 8257 | nsigs = (int) GDB_SIGNAL_LAST; |
| 8258 | sigs = (unsigned char *) alloca (nsigs); |
| 8259 | memset (sigs, 0, nsigs); |
| 8260 | |
| 8261 | /* Break the command line up into args. */ |
| 8262 | |
| 8263 | argv = gdb_buildargv (args); |
| 8264 | old_chain = make_cleanup_freeargv (argv); |
| 8265 | |
| 8266 | /* Walk through the args, looking for signal oursigs, signal names, and |
| 8267 | actions. Signal numbers and signal names may be interspersed with |
| 8268 | actions, with the actions being performed for all signals cumulatively |
| 8269 | specified. Signal ranges can be specified as <LOW>-<HIGH>. */ |
| 8270 | |
| 8271 | while (*argv != NULL) |
| 8272 | { |
| 8273 | wordlen = strlen (*argv); |
| 8274 | for (digits = 0; isdigit ((*argv)[digits]); digits++) |
| 8275 | {; |
| 8276 | } |
| 8277 | allsigs = 0; |
| 8278 | sigfirst = siglast = -1; |
| 8279 | |
| 8280 | if (wordlen >= 1 && !strncmp (*argv, "all", wordlen)) |
| 8281 | { |
| 8282 | /* Apply action to all signals except those used by the |
| 8283 | debugger. Silently skip those. */ |
| 8284 | allsigs = 1; |
| 8285 | sigfirst = 0; |
| 8286 | siglast = nsigs - 1; |
| 8287 | } |
| 8288 | else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen)) |
| 8289 | { |
| 8290 | SET_SIGS (nsigs, sigs, signal_stop); |
| 8291 | SET_SIGS (nsigs, sigs, signal_print); |
| 8292 | } |
| 8293 | else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen)) |
| 8294 | { |
| 8295 | UNSET_SIGS (nsigs, sigs, signal_program); |
| 8296 | } |
| 8297 | else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen)) |
| 8298 | { |
| 8299 | SET_SIGS (nsigs, sigs, signal_print); |
| 8300 | } |
| 8301 | else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen)) |
| 8302 | { |
| 8303 | SET_SIGS (nsigs, sigs, signal_program); |
| 8304 | } |
| 8305 | else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen)) |
| 8306 | { |
| 8307 | UNSET_SIGS (nsigs, sigs, signal_stop); |
| 8308 | } |
| 8309 | else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen)) |
| 8310 | { |
| 8311 | SET_SIGS (nsigs, sigs, signal_program); |
| 8312 | } |
| 8313 | else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen)) |
| 8314 | { |
| 8315 | UNSET_SIGS (nsigs, sigs, signal_print); |
| 8316 | UNSET_SIGS (nsigs, sigs, signal_stop); |
| 8317 | } |
| 8318 | else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen)) |
| 8319 | { |
| 8320 | UNSET_SIGS (nsigs, sigs, signal_program); |
| 8321 | } |
| 8322 | else if (digits > 0) |
| 8323 | { |
| 8324 | /* It is numeric. The numeric signal refers to our own |
| 8325 | internal signal numbering from target.h, not to host/target |
| 8326 | signal number. This is a feature; users really should be |
| 8327 | using symbolic names anyway, and the common ones like |
| 8328 | SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */ |
| 8329 | |
| 8330 | sigfirst = siglast = (int) |
| 8331 | gdb_signal_from_command (atoi (*argv)); |
| 8332 | if ((*argv)[digits] == '-') |
| 8333 | { |
| 8334 | siglast = (int) |
| 8335 | gdb_signal_from_command (atoi ((*argv) + digits + 1)); |
| 8336 | } |
| 8337 | if (sigfirst > siglast) |
| 8338 | { |
| 8339 | /* Bet he didn't figure we'd think of this case... */ |
| 8340 | signum = sigfirst; |
| 8341 | sigfirst = siglast; |
| 8342 | siglast = signum; |
| 8343 | } |
| 8344 | } |
| 8345 | else |
| 8346 | { |
| 8347 | oursig = gdb_signal_from_name (*argv); |
| 8348 | if (oursig != GDB_SIGNAL_UNKNOWN) |
| 8349 | { |
| 8350 | sigfirst = siglast = (int) oursig; |
| 8351 | } |
| 8352 | else |
| 8353 | { |
| 8354 | /* Not a number and not a recognized flag word => complain. */ |
| 8355 | error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv); |
| 8356 | } |
| 8357 | } |
| 8358 | |
| 8359 | /* If any signal numbers or symbol names were found, set flags for |
| 8360 | which signals to apply actions to. */ |
| 8361 | |
| 8362 | for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++) |
| 8363 | { |
| 8364 | switch ((enum gdb_signal) signum) |
| 8365 | { |
| 8366 | case GDB_SIGNAL_TRAP: |
| 8367 | case GDB_SIGNAL_INT: |
| 8368 | if (!allsigs && !sigs[signum]) |
| 8369 | { |
| 8370 | if (query (_("%s is used by the debugger.\n\ |
| 8371 | Are you sure you want to change it? "), |
| 8372 | gdb_signal_to_name ((enum gdb_signal) signum))) |
| 8373 | { |
| 8374 | sigs[signum] = 1; |
| 8375 | } |
| 8376 | else |
| 8377 | { |
| 8378 | printf_unfiltered (_("Not confirmed, unchanged.\n")); |
| 8379 | gdb_flush (gdb_stdout); |
| 8380 | } |
| 8381 | } |
| 8382 | break; |
| 8383 | case GDB_SIGNAL_0: |
| 8384 | case GDB_SIGNAL_DEFAULT: |
| 8385 | case GDB_SIGNAL_UNKNOWN: |
| 8386 | /* Make sure that "all" doesn't print these. */ |
| 8387 | break; |
| 8388 | default: |
| 8389 | sigs[signum] = 1; |
| 8390 | break; |
| 8391 | } |
| 8392 | } |
| 8393 | |
| 8394 | argv++; |
| 8395 | } |
| 8396 | |
| 8397 | for (signum = 0; signum < nsigs; signum++) |
| 8398 | if (sigs[signum]) |
| 8399 | { |
| 8400 | signal_cache_update (-1); |
| 8401 | target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass); |
| 8402 | target_program_signals ((int) GDB_SIGNAL_LAST, signal_program); |
| 8403 | |
| 8404 | if (from_tty) |
| 8405 | { |
| 8406 | /* Show the results. */ |
| 8407 | sig_print_header (); |
| 8408 | for (; signum < nsigs; signum++) |
| 8409 | if (sigs[signum]) |
| 8410 | sig_print_info ((enum gdb_signal) signum); |
| 8411 | } |
| 8412 | |
| 8413 | break; |
| 8414 | } |
| 8415 | |
| 8416 | do_cleanups (old_chain); |
| 8417 | } |
| 8418 | |
| 8419 | /* Complete the "handle" command. */ |
| 8420 | |
| 8421 | static VEC (char_ptr) * |
| 8422 | handle_completer (struct cmd_list_element *ignore, |
| 8423 | const char *text, const char *word) |
| 8424 | { |
| 8425 | VEC (char_ptr) *vec_signals, *vec_keywords, *return_val; |
| 8426 | static const char * const keywords[] = |
| 8427 | { |
| 8428 | "all", |
| 8429 | "stop", |
| 8430 | "ignore", |
| 8431 | "print", |
| 8432 | "pass", |
| 8433 | "nostop", |
| 8434 | "noignore", |
| 8435 | "noprint", |
| 8436 | "nopass", |
| 8437 | NULL, |
| 8438 | }; |
| 8439 | |
| 8440 | vec_signals = signal_completer (ignore, text, word); |
| 8441 | vec_keywords = complete_on_enum (keywords, word, word); |
| 8442 | |
| 8443 | return_val = VEC_merge (char_ptr, vec_signals, vec_keywords); |
| 8444 | VEC_free (char_ptr, vec_signals); |
| 8445 | VEC_free (char_ptr, vec_keywords); |
| 8446 | return return_val; |
| 8447 | } |
| 8448 | |
| 8449 | enum gdb_signal |
| 8450 | gdb_signal_from_command (int num) |
| 8451 | { |
| 8452 | if (num >= 1 && num <= 15) |
| 8453 | return (enum gdb_signal) num; |
| 8454 | error (_("Only signals 1-15 are valid as numeric signals.\n\ |
| 8455 | Use \"info signals\" for a list of symbolic signals.")); |
| 8456 | } |
| 8457 | |
| 8458 | /* Print current contents of the tables set by the handle command. |
| 8459 | It is possible we should just be printing signals actually used |
| 8460 | by the current target (but for things to work right when switching |
| 8461 | targets, all signals should be in the signal tables). */ |
| 8462 | |
| 8463 | static void |
| 8464 | signals_info (char *signum_exp, int from_tty) |
| 8465 | { |
| 8466 | enum gdb_signal oursig; |
| 8467 | |
| 8468 | sig_print_header (); |
| 8469 | |
| 8470 | if (signum_exp) |
| 8471 | { |
| 8472 | /* First see if this is a symbol name. */ |
| 8473 | oursig = gdb_signal_from_name (signum_exp); |
| 8474 | if (oursig == GDB_SIGNAL_UNKNOWN) |
| 8475 | { |
| 8476 | /* No, try numeric. */ |
| 8477 | oursig = |
| 8478 | gdb_signal_from_command (parse_and_eval_long (signum_exp)); |
| 8479 | } |
| 8480 | sig_print_info (oursig); |
| 8481 | return; |
| 8482 | } |
| 8483 | |
| 8484 | printf_filtered ("\n"); |
| 8485 | /* These ugly casts brought to you by the native VAX compiler. */ |
| 8486 | for (oursig = GDB_SIGNAL_FIRST; |
| 8487 | (int) oursig < (int) GDB_SIGNAL_LAST; |
| 8488 | oursig = (enum gdb_signal) ((int) oursig + 1)) |
| 8489 | { |
| 8490 | QUIT; |
| 8491 | |
| 8492 | if (oursig != GDB_SIGNAL_UNKNOWN |
| 8493 | && oursig != GDB_SIGNAL_DEFAULT && oursig != GDB_SIGNAL_0) |
| 8494 | sig_print_info (oursig); |
| 8495 | } |
| 8496 | |
| 8497 | printf_filtered (_("\nUse the \"handle\" command " |
| 8498 | "to change these tables.\n")); |
| 8499 | } |
| 8500 | |
| 8501 | /* Check if it makes sense to read $_siginfo from the current thread |
| 8502 | at this point. If not, throw an error. */ |
| 8503 | |
| 8504 | static void |
| 8505 | validate_siginfo_access (void) |
| 8506 | { |
| 8507 | /* No current inferior, no siginfo. */ |
| 8508 | if (ptid_equal (inferior_ptid, null_ptid)) |
| 8509 | error (_("No thread selected.")); |
| 8510 | |
| 8511 | /* Don't try to read from a dead thread. */ |
| 8512 | if (is_exited (inferior_ptid)) |
| 8513 | error (_("The current thread has terminated")); |
| 8514 | |
| 8515 | /* ... or from a spinning thread. */ |
| 8516 | if (is_running (inferior_ptid)) |
| 8517 | error (_("Selected thread is running.")); |
| 8518 | } |
| 8519 | |
| 8520 | /* The $_siginfo convenience variable is a bit special. We don't know |
| 8521 | for sure the type of the value until we actually have a chance to |
| 8522 | fetch the data. The type can change depending on gdbarch, so it is |
| 8523 | also dependent on which thread you have selected. |
| 8524 | |
| 8525 | 1. making $_siginfo be an internalvar that creates a new value on |
| 8526 | access. |
| 8527 | |
| 8528 | 2. making the value of $_siginfo be an lval_computed value. */ |
| 8529 | |
| 8530 | /* This function implements the lval_computed support for reading a |
| 8531 | $_siginfo value. */ |
| 8532 | |
| 8533 | static void |
| 8534 | siginfo_value_read (struct value *v) |
| 8535 | { |
| 8536 | LONGEST transferred; |
| 8537 | |
| 8538 | validate_siginfo_access (); |
| 8539 | |
| 8540 | transferred = |
| 8541 | target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO, |
| 8542 | NULL, |
| 8543 | value_contents_all_raw (v), |
| 8544 | value_offset (v), |
| 8545 | TYPE_LENGTH (value_type (v))); |
| 8546 | |
| 8547 | if (transferred != TYPE_LENGTH (value_type (v))) |
| 8548 | error (_("Unable to read siginfo")); |
| 8549 | } |
| 8550 | |
| 8551 | /* This function implements the lval_computed support for writing a |
| 8552 | $_siginfo value. */ |
| 8553 | |
| 8554 | static void |
| 8555 | siginfo_value_write (struct value *v, struct value *fromval) |
| 8556 | { |
| 8557 | LONGEST transferred; |
| 8558 | |
| 8559 | validate_siginfo_access (); |
| 8560 | |
| 8561 | transferred = target_write (¤t_target, |
| 8562 | TARGET_OBJECT_SIGNAL_INFO, |
| 8563 | NULL, |
| 8564 | value_contents_all_raw (fromval), |
| 8565 | value_offset (v), |
| 8566 | TYPE_LENGTH (value_type (fromval))); |
| 8567 | |
| 8568 | if (transferred != TYPE_LENGTH (value_type (fromval))) |
| 8569 | error (_("Unable to write siginfo")); |
| 8570 | } |
| 8571 | |
| 8572 | static const struct lval_funcs siginfo_value_funcs = |
| 8573 | { |
| 8574 | siginfo_value_read, |
| 8575 | siginfo_value_write |
| 8576 | }; |
| 8577 | |
| 8578 | /* Return a new value with the correct type for the siginfo object of |
| 8579 | the current thread using architecture GDBARCH. Return a void value |
| 8580 | if there's no object available. */ |
| 8581 | |
| 8582 | static struct value * |
| 8583 | siginfo_make_value (struct gdbarch *gdbarch, struct internalvar *var, |
| 8584 | void *ignore) |
| 8585 | { |
| 8586 | if (target_has_stack |
| 8587 | && !ptid_equal (inferior_ptid, null_ptid) |
| 8588 | && gdbarch_get_siginfo_type_p (gdbarch)) |
| 8589 | { |
| 8590 | struct type *type = gdbarch_get_siginfo_type (gdbarch); |
| 8591 | |
| 8592 | return allocate_computed_value (type, &siginfo_value_funcs, NULL); |
| 8593 | } |
| 8594 | |
| 8595 | return allocate_value (builtin_type (gdbarch)->builtin_void); |
| 8596 | } |
| 8597 | |
| 8598 | \f |
| 8599 | /* infcall_suspend_state contains state about the program itself like its |
| 8600 | registers and any signal it received when it last stopped. |
| 8601 | This state must be restored regardless of how the inferior function call |
| 8602 | ends (either successfully, or after it hits a breakpoint or signal) |
| 8603 | if the program is to properly continue where it left off. */ |
| 8604 | |
| 8605 | struct infcall_suspend_state |
| 8606 | { |
| 8607 | struct thread_suspend_state thread_suspend; |
| 8608 | |
| 8609 | /* Other fields: */ |
| 8610 | CORE_ADDR stop_pc; |
| 8611 | struct regcache *registers; |
| 8612 | |
| 8613 | /* Format of SIGINFO_DATA or NULL if it is not present. */ |
| 8614 | struct gdbarch *siginfo_gdbarch; |
| 8615 | |
| 8616 | /* The inferior format depends on SIGINFO_GDBARCH and it has a length of |
| 8617 | TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the |
| 8618 | content would be invalid. */ |
| 8619 | gdb_byte *siginfo_data; |
| 8620 | }; |
| 8621 | |
| 8622 | struct infcall_suspend_state * |
| 8623 | save_infcall_suspend_state (void) |
| 8624 | { |
| 8625 | struct infcall_suspend_state *inf_state; |
| 8626 | struct thread_info *tp = inferior_thread (); |
| 8627 | struct regcache *regcache = get_current_regcache (); |
| 8628 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 8629 | gdb_byte *siginfo_data = NULL; |
| 8630 | |
| 8631 | if (gdbarch_get_siginfo_type_p (gdbarch)) |
| 8632 | { |
| 8633 | struct type *type = gdbarch_get_siginfo_type (gdbarch); |
| 8634 | size_t len = TYPE_LENGTH (type); |
| 8635 | struct cleanup *back_to; |
| 8636 | |
| 8637 | siginfo_data = xmalloc (len); |
| 8638 | back_to = make_cleanup (xfree, siginfo_data); |
| 8639 | |
| 8640 | if (target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL, |
| 8641 | siginfo_data, 0, len) == len) |
| 8642 | discard_cleanups (back_to); |
| 8643 | else |
| 8644 | { |
| 8645 | /* Errors ignored. */ |
| 8646 | do_cleanups (back_to); |
| 8647 | siginfo_data = NULL; |
| 8648 | } |
| 8649 | } |
| 8650 | |
| 8651 | inf_state = XCNEW (struct infcall_suspend_state); |
| 8652 | |
| 8653 | if (siginfo_data) |
| 8654 | { |
| 8655 | inf_state->siginfo_gdbarch = gdbarch; |
| 8656 | inf_state->siginfo_data = siginfo_data; |
| 8657 | } |
| 8658 | |
| 8659 | inf_state->thread_suspend = tp->suspend; |
| 8660 | |
| 8661 | /* run_inferior_call will not use the signal due to its `proceed' call with |
| 8662 | GDB_SIGNAL_0 anyway. */ |
| 8663 | tp->suspend.stop_signal = GDB_SIGNAL_0; |
| 8664 | |
| 8665 | inf_state->stop_pc = stop_pc; |
| 8666 | |
| 8667 | inf_state->registers = regcache_dup (regcache); |
| 8668 | |
| 8669 | return inf_state; |
| 8670 | } |
| 8671 | |
| 8672 | /* Restore inferior session state to INF_STATE. */ |
| 8673 | |
| 8674 | void |
| 8675 | restore_infcall_suspend_state (struct infcall_suspend_state *inf_state) |
| 8676 | { |
| 8677 | struct thread_info *tp = inferior_thread (); |
| 8678 | struct regcache *regcache = get_current_regcache (); |
| 8679 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 8680 | |
| 8681 | tp->suspend = inf_state->thread_suspend; |
| 8682 | |
| 8683 | stop_pc = inf_state->stop_pc; |
| 8684 | |
| 8685 | if (inf_state->siginfo_gdbarch == gdbarch) |
| 8686 | { |
| 8687 | struct type *type = gdbarch_get_siginfo_type (gdbarch); |
| 8688 | |
| 8689 | /* Errors ignored. */ |
| 8690 | target_write (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL, |
| 8691 | inf_state->siginfo_data, 0, TYPE_LENGTH (type)); |
| 8692 | } |
| 8693 | |
| 8694 | /* The inferior can be gone if the user types "print exit(0)" |
| 8695 | (and perhaps other times). */ |
| 8696 | if (target_has_execution) |
| 8697 | /* NB: The register write goes through to the target. */ |
| 8698 | regcache_cpy (regcache, inf_state->registers); |
| 8699 | |
| 8700 | discard_infcall_suspend_state (inf_state); |
| 8701 | } |
| 8702 | |
| 8703 | static void |
| 8704 | do_restore_infcall_suspend_state_cleanup (void *state) |
| 8705 | { |
| 8706 | restore_infcall_suspend_state (state); |
| 8707 | } |
| 8708 | |
| 8709 | struct cleanup * |
| 8710 | make_cleanup_restore_infcall_suspend_state |
| 8711 | (struct infcall_suspend_state *inf_state) |
| 8712 | { |
| 8713 | return make_cleanup (do_restore_infcall_suspend_state_cleanup, inf_state); |
| 8714 | } |
| 8715 | |
| 8716 | void |
| 8717 | discard_infcall_suspend_state (struct infcall_suspend_state *inf_state) |
| 8718 | { |
| 8719 | regcache_xfree (inf_state->registers); |
| 8720 | xfree (inf_state->siginfo_data); |
| 8721 | xfree (inf_state); |
| 8722 | } |
| 8723 | |
| 8724 | struct regcache * |
| 8725 | get_infcall_suspend_state_regcache (struct infcall_suspend_state *inf_state) |
| 8726 | { |
| 8727 | return inf_state->registers; |
| 8728 | } |
| 8729 | |
| 8730 | /* infcall_control_state contains state regarding gdb's control of the |
| 8731 | inferior itself like stepping control. It also contains session state like |
| 8732 | the user's currently selected frame. */ |
| 8733 | |
| 8734 | struct infcall_control_state |
| 8735 | { |
| 8736 | struct thread_control_state thread_control; |
| 8737 | struct inferior_control_state inferior_control; |
| 8738 | |
| 8739 | /* Other fields: */ |
| 8740 | enum stop_stack_kind stop_stack_dummy; |
| 8741 | int stopped_by_random_signal; |
| 8742 | int stop_after_trap; |
| 8743 | |
| 8744 | /* ID if the selected frame when the inferior function call was made. */ |
| 8745 | struct frame_id selected_frame_id; |
| 8746 | }; |
| 8747 | |
| 8748 | /* Save all of the information associated with the inferior<==>gdb |
| 8749 | connection. */ |
| 8750 | |
| 8751 | struct infcall_control_state * |
| 8752 | save_infcall_control_state (void) |
| 8753 | { |
| 8754 | struct infcall_control_state *inf_status = |
| 8755 | XNEW (struct infcall_control_state); |
| 8756 | struct thread_info *tp = inferior_thread (); |
| 8757 | struct inferior *inf = current_inferior (); |
| 8758 | |
| 8759 | inf_status->thread_control = tp->control; |
| 8760 | inf_status->inferior_control = inf->control; |
| 8761 | |
| 8762 | tp->control.step_resume_breakpoint = NULL; |
| 8763 | tp->control.exception_resume_breakpoint = NULL; |
| 8764 | |
| 8765 | /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of |
| 8766 | chain. If caller's caller is walking the chain, they'll be happier if we |
| 8767 | hand them back the original chain when restore_infcall_control_state is |
| 8768 | called. */ |
| 8769 | tp->control.stop_bpstat = bpstat_copy (tp->control.stop_bpstat); |
| 8770 | |
| 8771 | /* Other fields: */ |
| 8772 | inf_status->stop_stack_dummy = stop_stack_dummy; |
| 8773 | inf_status->stopped_by_random_signal = stopped_by_random_signal; |
| 8774 | inf_status->stop_after_trap = stop_after_trap; |
| 8775 | |
| 8776 | inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL)); |
| 8777 | |
| 8778 | return inf_status; |
| 8779 | } |
| 8780 | |
| 8781 | static int |
| 8782 | restore_selected_frame (void *args) |
| 8783 | { |
| 8784 | struct frame_id *fid = (struct frame_id *) args; |
| 8785 | struct frame_info *frame; |
| 8786 | |
| 8787 | frame = frame_find_by_id (*fid); |
| 8788 | |
| 8789 | /* If inf_status->selected_frame_id is NULL, there was no previously |
| 8790 | selected frame. */ |
| 8791 | if (frame == NULL) |
| 8792 | { |
| 8793 | warning (_("Unable to restore previously selected frame.")); |
| 8794 | return 0; |
| 8795 | } |
| 8796 | |
| 8797 | select_frame (frame); |
| 8798 | |
| 8799 | return (1); |
| 8800 | } |
| 8801 | |
| 8802 | /* Restore inferior session state to INF_STATUS. */ |
| 8803 | |
| 8804 | void |
| 8805 | restore_infcall_control_state (struct infcall_control_state *inf_status) |
| 8806 | { |
| 8807 | struct thread_info *tp = inferior_thread (); |
| 8808 | struct inferior *inf = current_inferior (); |
| 8809 | |
| 8810 | if (tp->control.step_resume_breakpoint) |
| 8811 | tp->control.step_resume_breakpoint->disposition = disp_del_at_next_stop; |
| 8812 | |
| 8813 | if (tp->control.exception_resume_breakpoint) |
| 8814 | tp->control.exception_resume_breakpoint->disposition |
| 8815 | = disp_del_at_next_stop; |
| 8816 | |
| 8817 | /* Handle the bpstat_copy of the chain. */ |
| 8818 | bpstat_clear (&tp->control.stop_bpstat); |
| 8819 | |
| 8820 | tp->control = inf_status->thread_control; |
| 8821 | inf->control = inf_status->inferior_control; |
| 8822 | |
| 8823 | /* Other fields: */ |
| 8824 | stop_stack_dummy = inf_status->stop_stack_dummy; |
| 8825 | stopped_by_random_signal = inf_status->stopped_by_random_signal; |
| 8826 | stop_after_trap = inf_status->stop_after_trap; |
| 8827 | |
| 8828 | if (target_has_stack) |
| 8829 | { |
| 8830 | /* The point of catch_errors is that if the stack is clobbered, |
| 8831 | walking the stack might encounter a garbage pointer and |
| 8832 | error() trying to dereference it. */ |
| 8833 | if (catch_errors |
| 8834 | (restore_selected_frame, &inf_status->selected_frame_id, |
| 8835 | "Unable to restore previously selected frame:\n", |
| 8836 | RETURN_MASK_ERROR) == 0) |
| 8837 | /* Error in restoring the selected frame. Select the innermost |
| 8838 | frame. */ |
| 8839 | select_frame (get_current_frame ()); |
| 8840 | } |
| 8841 | |
| 8842 | xfree (inf_status); |
| 8843 | } |
| 8844 | |
| 8845 | static void |
| 8846 | do_restore_infcall_control_state_cleanup (void *sts) |
| 8847 | { |
| 8848 | restore_infcall_control_state (sts); |
| 8849 | } |
| 8850 | |
| 8851 | struct cleanup * |
| 8852 | make_cleanup_restore_infcall_control_state |
| 8853 | (struct infcall_control_state *inf_status) |
| 8854 | { |
| 8855 | return make_cleanup (do_restore_infcall_control_state_cleanup, inf_status); |
| 8856 | } |
| 8857 | |
| 8858 | void |
| 8859 | discard_infcall_control_state (struct infcall_control_state *inf_status) |
| 8860 | { |
| 8861 | if (inf_status->thread_control.step_resume_breakpoint) |
| 8862 | inf_status->thread_control.step_resume_breakpoint->disposition |
| 8863 | = disp_del_at_next_stop; |
| 8864 | |
| 8865 | if (inf_status->thread_control.exception_resume_breakpoint) |
| 8866 | inf_status->thread_control.exception_resume_breakpoint->disposition |
| 8867 | = disp_del_at_next_stop; |
| 8868 | |
| 8869 | /* See save_infcall_control_state for info on stop_bpstat. */ |
| 8870 | bpstat_clear (&inf_status->thread_control.stop_bpstat); |
| 8871 | |
| 8872 | xfree (inf_status); |
| 8873 | } |
| 8874 | \f |
| 8875 | /* restore_inferior_ptid() will be used by the cleanup machinery |
| 8876 | to restore the inferior_ptid value saved in a call to |
| 8877 | save_inferior_ptid(). */ |
| 8878 | |
| 8879 | static void |
| 8880 | restore_inferior_ptid (void *arg) |
| 8881 | { |
| 8882 | ptid_t *saved_ptid_ptr = arg; |
| 8883 | |
| 8884 | inferior_ptid = *saved_ptid_ptr; |
| 8885 | xfree (arg); |
| 8886 | } |
| 8887 | |
| 8888 | /* Save the value of inferior_ptid so that it may be restored by a |
| 8889 | later call to do_cleanups(). Returns the struct cleanup pointer |
| 8890 | needed for later doing the cleanup. */ |
| 8891 | |
| 8892 | struct cleanup * |
| 8893 | save_inferior_ptid (void) |
| 8894 | { |
| 8895 | ptid_t *saved_ptid_ptr = XNEW (ptid_t); |
| 8896 | |
| 8897 | *saved_ptid_ptr = inferior_ptid; |
| 8898 | return make_cleanup (restore_inferior_ptid, saved_ptid_ptr); |
| 8899 | } |
| 8900 | |
| 8901 | /* See infrun.h. */ |
| 8902 | |
| 8903 | void |
| 8904 | clear_exit_convenience_vars (void) |
| 8905 | { |
| 8906 | clear_internalvar (lookup_internalvar ("_exitsignal")); |
| 8907 | clear_internalvar (lookup_internalvar ("_exitcode")); |
| 8908 | } |
| 8909 | \f |
| 8910 | |
| 8911 | /* User interface for reverse debugging: |
| 8912 | Set exec-direction / show exec-direction commands |
| 8913 | (returns error unless target implements to_set_exec_direction method). */ |
| 8914 | |
| 8915 | int execution_direction = EXEC_FORWARD; |
| 8916 | static const char exec_forward[] = "forward"; |
| 8917 | static const char exec_reverse[] = "reverse"; |
| 8918 | static const char *exec_direction = exec_forward; |
| 8919 | static const char *const exec_direction_names[] = { |
| 8920 | exec_forward, |
| 8921 | exec_reverse, |
| 8922 | NULL |
| 8923 | }; |
| 8924 | |
| 8925 | static void |
| 8926 | set_exec_direction_func (char *args, int from_tty, |
| 8927 | struct cmd_list_element *cmd) |
| 8928 | { |
| 8929 | if (target_can_execute_reverse) |
| 8930 | { |
| 8931 | if (!strcmp (exec_direction, exec_forward)) |
| 8932 | execution_direction = EXEC_FORWARD; |
| 8933 | else if (!strcmp (exec_direction, exec_reverse)) |
| 8934 | execution_direction = EXEC_REVERSE; |
| 8935 | } |
| 8936 | else |
| 8937 | { |
| 8938 | exec_direction = exec_forward; |
| 8939 | error (_("Target does not support this operation.")); |
| 8940 | } |
| 8941 | } |
| 8942 | |
| 8943 | static void |
| 8944 | show_exec_direction_func (struct ui_file *out, int from_tty, |
| 8945 | struct cmd_list_element *cmd, const char *value) |
| 8946 | { |
| 8947 | switch (execution_direction) { |
| 8948 | case EXEC_FORWARD: |
| 8949 | fprintf_filtered (out, _("Forward.\n")); |
| 8950 | break; |
| 8951 | case EXEC_REVERSE: |
| 8952 | fprintf_filtered (out, _("Reverse.\n")); |
| 8953 | break; |
| 8954 | default: |
| 8955 | internal_error (__FILE__, __LINE__, |
| 8956 | _("bogus execution_direction value: %d"), |
| 8957 | (int) execution_direction); |
| 8958 | } |
| 8959 | } |
| 8960 | |
| 8961 | static void |
| 8962 | show_schedule_multiple (struct ui_file *file, int from_tty, |
| 8963 | struct cmd_list_element *c, const char *value) |
| 8964 | { |
| 8965 | fprintf_filtered (file, _("Resuming the execution of threads " |
| 8966 | "of all processes is %s.\n"), value); |
| 8967 | } |
| 8968 | |
| 8969 | /* Implementation of `siginfo' variable. */ |
| 8970 | |
| 8971 | static const struct internalvar_funcs siginfo_funcs = |
| 8972 | { |
| 8973 | siginfo_make_value, |
| 8974 | NULL, |
| 8975 | NULL |
| 8976 | }; |
| 8977 | |
| 8978 | /* Callback for infrun's target events source. This is marked when a |
| 8979 | thread has a pending status to process. */ |
| 8980 | |
| 8981 | static void |
| 8982 | infrun_async_inferior_event_handler (gdb_client_data data) |
| 8983 | { |
| 8984 | inferior_event_handler (INF_REG_EVENT, NULL); |
| 8985 | } |
| 8986 | |
| 8987 | void |
| 8988 | _initialize_infrun (void) |
| 8989 | { |
| 8990 | int i; |
| 8991 | int numsigs; |
| 8992 | struct cmd_list_element *c; |
| 8993 | |
| 8994 | /* Register extra event sources in the event loop. */ |
| 8995 | infrun_async_inferior_event_token |
| 8996 | = create_async_event_handler (infrun_async_inferior_event_handler, NULL); |
| 8997 | |
| 8998 | add_info ("signals", signals_info, _("\ |
| 8999 | What debugger does when program gets various signals.\n\ |
| 9000 | Specify a signal as argument to print info on that signal only.")); |
| 9001 | add_info_alias ("handle", "signals", 0); |
| 9002 | |
| 9003 | c = add_com ("handle", class_run, handle_command, _("\ |
| 9004 | Specify how to handle signals.\n\ |
| 9005 | Usage: handle SIGNAL [ACTIONS]\n\ |
| 9006 | Args are signals and actions to apply to those signals.\n\ |
| 9007 | If no actions are specified, the current settings for the specified signals\n\ |
| 9008 | will be displayed instead.\n\ |
| 9009 | \n\ |
| 9010 | Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\ |
| 9011 | from 1-15 are allowed for compatibility with old versions of GDB.\n\ |
| 9012 | Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\ |
| 9013 | The special arg \"all\" is recognized to mean all signals except those\n\ |
| 9014 | used by the debugger, typically SIGTRAP and SIGINT.\n\ |
| 9015 | \n\ |
| 9016 | Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\ |
| 9017 | \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\ |
| 9018 | Stop means reenter debugger if this signal happens (implies print).\n\ |
| 9019 | Print means print a message if this signal happens.\n\ |
| 9020 | Pass means let program see this signal; otherwise program doesn't know.\n\ |
| 9021 | Ignore is a synonym for nopass and noignore is a synonym for pass.\n\ |
| 9022 | Pass and Stop may be combined.\n\ |
| 9023 | \n\ |
| 9024 | Multiple signals may be specified. Signal numbers and signal names\n\ |
| 9025 | may be interspersed with actions, with the actions being performed for\n\ |
| 9026 | all signals cumulatively specified.")); |
| 9027 | set_cmd_completer (c, handle_completer); |
| 9028 | |
| 9029 | if (!dbx_commands) |
| 9030 | stop_command = add_cmd ("stop", class_obscure, |
| 9031 | not_just_help_class_command, _("\ |
| 9032 | There is no `stop' command, but you can set a hook on `stop'.\n\ |
| 9033 | This allows you to set a list of commands to be run each time execution\n\ |
| 9034 | of the program stops."), &cmdlist); |
| 9035 | |
| 9036 | add_setshow_zuinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\ |
| 9037 | Set inferior debugging."), _("\ |
| 9038 | Show inferior debugging."), _("\ |
| 9039 | When non-zero, inferior specific debugging is enabled."), |
| 9040 | NULL, |
| 9041 | show_debug_infrun, |
| 9042 | &setdebuglist, &showdebuglist); |
| 9043 | |
| 9044 | add_setshow_boolean_cmd ("displaced", class_maintenance, |
| 9045 | &debug_displaced, _("\ |
| 9046 | Set displaced stepping debugging."), _("\ |
| 9047 | Show displaced stepping debugging."), _("\ |
| 9048 | When non-zero, displaced stepping specific debugging is enabled."), |
| 9049 | NULL, |
| 9050 | show_debug_displaced, |
| 9051 | &setdebuglist, &showdebuglist); |
| 9052 | |
| 9053 | add_setshow_boolean_cmd ("non-stop", no_class, |
| 9054 | &non_stop_1, _("\ |
| 9055 | Set whether gdb controls the inferior in non-stop mode."), _("\ |
| 9056 | Show whether gdb controls the inferior in non-stop mode."), _("\ |
| 9057 | When debugging a multi-threaded program and this setting is\n\ |
| 9058 | off (the default, also called all-stop mode), when one thread stops\n\ |
| 9059 | (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\ |
| 9060 | all other threads in the program while you interact with the thread of\n\ |
| 9061 | interest. When you continue or step a thread, you can allow the other\n\ |
| 9062 | threads to run, or have them remain stopped, but while you inspect any\n\ |
| 9063 | thread's state, all threads stop.\n\ |
| 9064 | \n\ |
| 9065 | In non-stop mode, when one thread stops, other threads can continue\n\ |
| 9066 | to run freely. You'll be able to step each thread independently,\n\ |
| 9067 | leave it stopped or free to run as needed."), |
| 9068 | set_non_stop, |
| 9069 | show_non_stop, |
| 9070 | &setlist, |
| 9071 | &showlist); |
| 9072 | |
| 9073 | numsigs = (int) GDB_SIGNAL_LAST; |
| 9074 | signal_stop = XNEWVEC (unsigned char, numsigs); |
| 9075 | signal_print = XNEWVEC (unsigned char, numsigs); |
| 9076 | signal_program = XNEWVEC (unsigned char, numsigs); |
| 9077 | signal_catch = XNEWVEC (unsigned char, numsigs); |
| 9078 | signal_pass = XNEWVEC (unsigned char, numsigs); |
| 9079 | for (i = 0; i < numsigs; i++) |
| 9080 | { |
| 9081 | signal_stop[i] = 1; |
| 9082 | signal_print[i] = 1; |
| 9083 | signal_program[i] = 1; |
| 9084 | signal_catch[i] = 0; |
| 9085 | } |
| 9086 | |
| 9087 | /* Signals caused by debugger's own actions should not be given to |
| 9088 | the program afterwards. |
| 9089 | |
| 9090 | Do not deliver GDB_SIGNAL_TRAP by default, except when the user |
| 9091 | explicitly specifies that it should be delivered to the target |
| 9092 | program. Typically, that would occur when a user is debugging a |
| 9093 | target monitor on a simulator: the target monitor sets a |
| 9094 | breakpoint; the simulator encounters this breakpoint and halts |
| 9095 | the simulation handing control to GDB; GDB, noting that the stop |
| 9096 | address doesn't map to any known breakpoint, returns control back |
| 9097 | to the simulator; the simulator then delivers the hardware |
| 9098 | equivalent of a GDB_SIGNAL_TRAP to the program being |
| 9099 | debugged. */ |
| 9100 | signal_program[GDB_SIGNAL_TRAP] = 0; |
| 9101 | signal_program[GDB_SIGNAL_INT] = 0; |
| 9102 | |
| 9103 | /* Signals that are not errors should not normally enter the debugger. */ |
| 9104 | signal_stop[GDB_SIGNAL_ALRM] = 0; |
| 9105 | signal_print[GDB_SIGNAL_ALRM] = 0; |
| 9106 | signal_stop[GDB_SIGNAL_VTALRM] = 0; |
| 9107 | signal_print[GDB_SIGNAL_VTALRM] = 0; |
| 9108 | signal_stop[GDB_SIGNAL_PROF] = 0; |
| 9109 | signal_print[GDB_SIGNAL_PROF] = 0; |
| 9110 | signal_stop[GDB_SIGNAL_CHLD] = 0; |
| 9111 | signal_print[GDB_SIGNAL_CHLD] = 0; |
| 9112 | signal_stop[GDB_SIGNAL_IO] = 0; |
| 9113 | signal_print[GDB_SIGNAL_IO] = 0; |
| 9114 | signal_stop[GDB_SIGNAL_POLL] = 0; |
| 9115 | signal_print[GDB_SIGNAL_POLL] = 0; |
| 9116 | signal_stop[GDB_SIGNAL_URG] = 0; |
| 9117 | signal_print[GDB_SIGNAL_URG] = 0; |
| 9118 | signal_stop[GDB_SIGNAL_WINCH] = 0; |
| 9119 | signal_print[GDB_SIGNAL_WINCH] = 0; |
| 9120 | signal_stop[GDB_SIGNAL_PRIO] = 0; |
| 9121 | signal_print[GDB_SIGNAL_PRIO] = 0; |
| 9122 | |
| 9123 | /* These signals are used internally by user-level thread |
| 9124 | implementations. (See signal(5) on Solaris.) Like the above |
| 9125 | signals, a healthy program receives and handles them as part of |
| 9126 | its normal operation. */ |
| 9127 | signal_stop[GDB_SIGNAL_LWP] = 0; |
| 9128 | signal_print[GDB_SIGNAL_LWP] = 0; |
| 9129 | signal_stop[GDB_SIGNAL_WAITING] = 0; |
| 9130 | signal_print[GDB_SIGNAL_WAITING] = 0; |
| 9131 | signal_stop[GDB_SIGNAL_CANCEL] = 0; |
| 9132 | signal_print[GDB_SIGNAL_CANCEL] = 0; |
| 9133 | |
| 9134 | /* Update cached state. */ |
| 9135 | signal_cache_update (-1); |
| 9136 | |
| 9137 | add_setshow_zinteger_cmd ("stop-on-solib-events", class_support, |
| 9138 | &stop_on_solib_events, _("\ |
| 9139 | Set stopping for shared library events."), _("\ |
| 9140 | Show stopping for shared library events."), _("\ |
| 9141 | If nonzero, gdb will give control to the user when the dynamic linker\n\ |
| 9142 | notifies gdb of shared library events. The most common event of interest\n\ |
| 9143 | to the user would be loading/unloading of a new library."), |
| 9144 | set_stop_on_solib_events, |
| 9145 | show_stop_on_solib_events, |
| 9146 | &setlist, &showlist); |
| 9147 | |
| 9148 | add_setshow_enum_cmd ("follow-fork-mode", class_run, |
| 9149 | follow_fork_mode_kind_names, |
| 9150 | &follow_fork_mode_string, _("\ |
| 9151 | Set debugger response to a program call of fork or vfork."), _("\ |
| 9152 | Show debugger response to a program call of fork or vfork."), _("\ |
| 9153 | A fork or vfork creates a new process. follow-fork-mode can be:\n\ |
| 9154 | parent - the original process is debugged after a fork\n\ |
| 9155 | child - the new process is debugged after a fork\n\ |
| 9156 | The unfollowed process will continue to run.\n\ |
| 9157 | By default, the debugger will follow the parent process."), |
| 9158 | NULL, |
| 9159 | show_follow_fork_mode_string, |
| 9160 | &setlist, &showlist); |
| 9161 | |
| 9162 | add_setshow_enum_cmd ("follow-exec-mode", class_run, |
| 9163 | follow_exec_mode_names, |
| 9164 | &follow_exec_mode_string, _("\ |
| 9165 | Set debugger response to a program call of exec."), _("\ |
| 9166 | Show debugger response to a program call of exec."), _("\ |
| 9167 | An exec call replaces the program image of a process.\n\ |
| 9168 | \n\ |
| 9169 | follow-exec-mode can be:\n\ |
| 9170 | \n\ |
| 9171 | new - the debugger creates a new inferior and rebinds the process\n\ |
| 9172 | to this new inferior. The program the process was running before\n\ |
| 9173 | the exec call can be restarted afterwards by restarting the original\n\ |
| 9174 | inferior.\n\ |
| 9175 | \n\ |
| 9176 | same - the debugger keeps the process bound to the same inferior.\n\ |
| 9177 | The new executable image replaces the previous executable loaded in\n\ |
| 9178 | the inferior. Restarting the inferior after the exec call restarts\n\ |
| 9179 | the executable the process was running after the exec call.\n\ |
| 9180 | \n\ |
| 9181 | By default, the debugger will use the same inferior."), |
| 9182 | NULL, |
| 9183 | show_follow_exec_mode_string, |
| 9184 | &setlist, &showlist); |
| 9185 | |
| 9186 | add_setshow_enum_cmd ("scheduler-locking", class_run, |
| 9187 | scheduler_enums, &scheduler_mode, _("\ |
| 9188 | Set mode for locking scheduler during execution."), _("\ |
| 9189 | Show mode for locking scheduler during execution."), _("\ |
| 9190 | off == no locking (threads may preempt at any time)\n\ |
| 9191 | on == full locking (no thread except the current thread may run)\n\ |
| 9192 | step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\ |
| 9193 | In this mode, other threads may run during other commands."), |
| 9194 | set_schedlock_func, /* traps on target vector */ |
| 9195 | show_scheduler_mode, |
| 9196 | &setlist, &showlist); |
| 9197 | |
| 9198 | add_setshow_boolean_cmd ("schedule-multiple", class_run, &sched_multi, _("\ |
| 9199 | Set mode for resuming threads of all processes."), _("\ |
| 9200 | Show mode for resuming threads of all processes."), _("\ |
| 9201 | When on, execution commands (such as 'continue' or 'next') resume all\n\ |
| 9202 | threads of all processes. When off (which is the default), execution\n\ |
| 9203 | commands only resume the threads of the current process. The set of\n\ |
| 9204 | threads that are resumed is further refined by the scheduler-locking\n\ |
| 9205 | mode (see help set scheduler-locking)."), |
| 9206 | NULL, |
| 9207 | show_schedule_multiple, |
| 9208 | &setlist, &showlist); |
| 9209 | |
| 9210 | add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\ |
| 9211 | Set mode of the step operation."), _("\ |
| 9212 | Show mode of the step operation."), _("\ |
| 9213 | When set, doing a step over a function without debug line information\n\ |
| 9214 | will stop at the first instruction of that function. Otherwise, the\n\ |
| 9215 | function is skipped and the step command stops at a different source line."), |
| 9216 | NULL, |
| 9217 | show_step_stop_if_no_debug, |
| 9218 | &setlist, &showlist); |
| 9219 | |
| 9220 | add_setshow_auto_boolean_cmd ("displaced-stepping", class_run, |
| 9221 | &can_use_displaced_stepping, _("\ |
| 9222 | Set debugger's willingness to use displaced stepping."), _("\ |
| 9223 | Show debugger's willingness to use displaced stepping."), _("\ |
| 9224 | If on, gdb will use displaced stepping to step over breakpoints if it is\n\ |
| 9225 | supported by the target architecture. If off, gdb will not use displaced\n\ |
| 9226 | stepping to step over breakpoints, even if such is supported by the target\n\ |
| 9227 | architecture. If auto (which is the default), gdb will use displaced stepping\n\ |
| 9228 | if the target architecture supports it and non-stop mode is active, but will not\n\ |
| 9229 | use it in all-stop mode (see help set non-stop)."), |
| 9230 | NULL, |
| 9231 | show_can_use_displaced_stepping, |
| 9232 | &setlist, &showlist); |
| 9233 | |
| 9234 | add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names, |
| 9235 | &exec_direction, _("Set direction of execution.\n\ |
| 9236 | Options are 'forward' or 'reverse'."), |
| 9237 | _("Show direction of execution (forward/reverse)."), |
| 9238 | _("Tells gdb whether to execute forward or backward."), |
| 9239 | set_exec_direction_func, show_exec_direction_func, |
| 9240 | &setlist, &showlist); |
| 9241 | |
| 9242 | /* Set/show detach-on-fork: user-settable mode. */ |
| 9243 | |
| 9244 | add_setshow_boolean_cmd ("detach-on-fork", class_run, &detach_fork, _("\ |
| 9245 | Set whether gdb will detach the child of a fork."), _("\ |
| 9246 | Show whether gdb will detach the child of a fork."), _("\ |
| 9247 | Tells gdb whether to detach the child of a fork."), |
| 9248 | NULL, NULL, &setlist, &showlist); |
| 9249 | |
| 9250 | /* Set/show disable address space randomization mode. */ |
| 9251 | |
| 9252 | add_setshow_boolean_cmd ("disable-randomization", class_support, |
| 9253 | &disable_randomization, _("\ |
| 9254 | Set disabling of debuggee's virtual address space randomization."), _("\ |
| 9255 | Show disabling of debuggee's virtual address space randomization."), _("\ |
| 9256 | When this mode is on (which is the default), randomization of the virtual\n\ |
| 9257 | address space is disabled. Standalone programs run with the randomization\n\ |
| 9258 | enabled by default on some platforms."), |
| 9259 | &set_disable_randomization, |
| 9260 | &show_disable_randomization, |
| 9261 | &setlist, &showlist); |
| 9262 | |
| 9263 | /* ptid initializations */ |
| 9264 | inferior_ptid = null_ptid; |
| 9265 | target_last_wait_ptid = minus_one_ptid; |
| 9266 | |
| 9267 | observer_attach_thread_ptid_changed (infrun_thread_ptid_changed); |
| 9268 | observer_attach_thread_stop_requested (infrun_thread_stop_requested); |
| 9269 | observer_attach_thread_exit (infrun_thread_thread_exit); |
| 9270 | observer_attach_inferior_exit (infrun_inferior_exit); |
| 9271 | |
| 9272 | /* Explicitly create without lookup, since that tries to create a |
| 9273 | value with a void typed value, and when we get here, gdbarch |
| 9274 | isn't initialized yet. At this point, we're quite sure there |
| 9275 | isn't another convenience variable of the same name. */ |
| 9276 | create_internalvar_type_lazy ("_siginfo", &siginfo_funcs, NULL); |
| 9277 | |
| 9278 | add_setshow_boolean_cmd ("observer", no_class, |
| 9279 | &observer_mode_1, _("\ |
| 9280 | Set whether gdb controls the inferior in observer mode."), _("\ |
| 9281 | Show whether gdb controls the inferior in observer mode."), _("\ |
| 9282 | In observer mode, GDB can get data from the inferior, but not\n\ |
| 9283 | affect its execution. Registers and memory may not be changed,\n\ |
| 9284 | breakpoints may not be set, and the program cannot be interrupted\n\ |
| 9285 | or signalled."), |
| 9286 | set_observer_mode, |
| 9287 | show_observer_mode, |
| 9288 | &setlist, |
| 9289 | &showlist); |
| 9290 | } |