| 1 | /* Low level interface for debugging GNU/Linux threads for GDB, |
| 2 | the GNU debugger. |
| 3 | Copyright 1998, 1999 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 2 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program; if not, write to the Free Software |
| 19 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 20 | |
| 21 | /* This module implements the debugging interface of the linuxthreads package |
| 22 | of the glibc. This package implements a simple clone()-based implementation |
| 23 | of Posix threads for Linux. To use this module, be sure that you have at |
| 24 | least the version of the linuxthreads package that holds the support of |
| 25 | GDB (currently 0.8 included in the glibc-2.0.7). |
| 26 | |
| 27 | Right now, the linuxthreads package does not care of priority scheduling, |
| 28 | so, neither this module does; In particular, the threads are resumed |
| 29 | in any order, which could lead to different scheduling than the one |
| 30 | happening when GDB does not control the execution. |
| 31 | |
| 32 | The latest point is that ptrace(PT_ATTACH, ...) is intrusive in Linux: |
| 33 | When a process is attached, then the attaching process becomes the current |
| 34 | parent of the attached process, and the old parent has lost this child. |
| 35 | If the old parent does a wait[...](), then this child is no longer |
| 36 | considered by the kernel as a child of the old parent, thus leading to |
| 37 | results of the call different when the child is attached and when it's not. |
| 38 | |
| 39 | A fix has been submitted to the Linux community to solve this problem, |
| 40 | which consequences are not visible to the application itself, but on the |
| 41 | process which may wait() for the completion of the application (mostly, |
| 42 | it may consider that the application no longer exists (errno == ECHILD), |
| 43 | although it does, and thus being unable to get the exit status and resource |
| 44 | usage of the child. If by chance, it is able to wait() for the application |
| 45 | after it has died (by receiving first a SIGCHILD, and then doing a wait(), |
| 46 | then the exit status and resource usage may be wrong, because the |
| 47 | linuxthreads package heavily relies on wait() synchronization to keep |
| 48 | them correct. */ |
| 49 | |
| 50 | #include "defs.h" |
| 51 | #include <sys/types.h> /* for pid_t */ |
| 52 | #include <sys/ptrace.h> /* for PT_* flags */ |
| 53 | #include "gdb_wait.h" /* for WUNTRACED and __WCLONE flags */ |
| 54 | #include <signal.h> /* for struct sigaction and NSIG */ |
| 55 | #include <sys/utsname.h> |
| 56 | |
| 57 | #include "target.h" |
| 58 | #include "inferior.h" |
| 59 | #include "gdbcore.h" |
| 60 | #include "gdbthread.h" |
| 61 | #include "gdbcmd.h" |
| 62 | #include "breakpoint.h" |
| 63 | |
| 64 | #ifndef PT_ATTACH |
| 65 | #define PT_ATTACH PTRACE_ATTACH |
| 66 | #endif |
| 67 | #ifndef PT_KILL |
| 68 | #define PT_KILL PTRACE_KILL |
| 69 | #endif |
| 70 | #ifndef PT_READ_U |
| 71 | #define PT_READ_U PTRACE_PEEKUSR |
| 72 | #endif |
| 73 | |
| 74 | #ifdef NSIG |
| 75 | #define LINUXTHREAD_NSIG NSIG |
| 76 | #else |
| 77 | #ifdef _NSIG |
| 78 | #define LINUXTHREAD_NSIG _NSIG |
| 79 | #endif |
| 80 | #endif |
| 81 | |
| 82 | extern int child_suppress_run; /* make inftarg.c non-runnable */ |
| 83 | struct target_ops linuxthreads_ops; /* Forward declaration */ |
| 84 | extern struct target_ops child_ops; /* target vector for inftarg.c */ |
| 85 | |
| 86 | static CORE_ADDR linuxthreads_handles; /* array of linuxthreads handles */ |
| 87 | static CORE_ADDR linuxthreads_manager; /* pid of linuxthreads manager thread */ |
| 88 | static CORE_ADDR linuxthreads_initial; /* pid of linuxthreads initial thread */ |
| 89 | static CORE_ADDR linuxthreads_debug; /* linuxthreads internal debug flag */ |
| 90 | static CORE_ADDR linuxthreads_num; /* number of valid handle entries */ |
| 91 | |
| 92 | static int linuxthreads_max; /* Maximum number of linuxthreads. |
| 93 | Zero if this executable doesn't use |
| 94 | threads, or wasn't linked with a |
| 95 | debugger-friendly version of the |
| 96 | linuxthreads library. */ |
| 97 | |
| 98 | static int linuxthreads_sizeof_handle; /* size of a linuxthreads handle */ |
| 99 | static int linuxthreads_offset_descr; /* h_descr offset of the linuxthreads |
| 100 | handle */ |
| 101 | static int linuxthreads_offset_pid; /* p_pid offset of the linuxthreads |
| 102 | descr */ |
| 103 | |
| 104 | static int linuxthreads_manager_pid; /* manager pid */ |
| 105 | static int linuxthreads_initial_pid; /* initial pid */ |
| 106 | |
| 107 | /* These variables form a bag of threads with interesting status. If |
| 108 | wait_thread (PID) finds that PID stopped for some interesting |
| 109 | reason (i.e. anything other than stopped with SIGSTOP), then it |
| 110 | records its status in this queue. linuxthreads_wait and |
| 111 | linuxthreads_find_trap extract processes from here. */ |
| 112 | static int *linuxthreads_wait_pid; /* wait array of pid */ |
| 113 | static int *linuxthreads_wait_status; /* wait array of status */ |
| 114 | static int linuxthreads_wait_last; /* index of last valid elt in |
| 115 | linuxthreads_wait_{pid,status} */ |
| 116 | |
| 117 | static sigset_t linuxthreads_block_mask; /* sigset without SIGCHLD */ |
| 118 | |
| 119 | static int linuxthreads_step_pid; /* current stepped pid */ |
| 120 | static int linuxthreads_step_signo; /* current stepped target signal */ |
| 121 | static int linuxthreads_exit_status; /* exit status of initial thread */ |
| 122 | |
| 123 | static int linuxthreads_inferior_pid; /* temporary internal inferior pid */ |
| 124 | static int linuxthreads_breakpoint_pid; /* last pid that hit a breakpoint */ |
| 125 | static int linuxthreads_attach_pending; /* attach command without wait */ |
| 126 | |
| 127 | static int linuxthreads_breakpoints_inserted; /* any breakpoints inserted */ |
| 128 | |
| 129 | /* LinuxThreads uses certain signals for communication between |
| 130 | processes; we need to tell GDB to pass them through silently to the |
| 131 | inferior. The LinuxThreads library has global variables we can |
| 132 | read containing the relevant signal numbers, but since the signal |
| 133 | numbers are chosen at run-time, those variables aren't initialized |
| 134 | until the shared library's constructors have had a chance to run. */ |
| 135 | |
| 136 | struct linuxthreads_signal { |
| 137 | |
| 138 | /* The name of the LinuxThreads library variable that contains |
| 139 | the signal number. */ |
| 140 | char *var; |
| 141 | |
| 142 | /* True if this variable must exist for us to debug properly. */ |
| 143 | int required; |
| 144 | |
| 145 | /* The variable's address in the inferior, or zero if the |
| 146 | LinuxThreads library hasn't been loaded into this inferior yet. */ |
| 147 | CORE_ADDR addr; |
| 148 | |
| 149 | /* The signal number, or zero if we don't know yet (either because |
| 150 | we haven't found the variable, or it hasn't been initialized). |
| 151 | This is an actual target signal number that you could pass to |
| 152 | `kill', not a GDB signal number. */ |
| 153 | int signal; |
| 154 | |
| 155 | /* GDB's original settings for `stop' and `print' for this signal. |
| 156 | We restore them when the user selects a different executable. |
| 157 | Invariant: if sig->signal != 0, then sig->{stop,print} contain |
| 158 | the original settings. */ |
| 159 | int stop, print; |
| 160 | }; |
| 161 | |
| 162 | struct linuxthreads_signal linuxthreads_sig_restart = { |
| 163 | "__pthread_sig_restart", 1, 0, 0, 0, 0 |
| 164 | }; |
| 165 | struct linuxthreads_signal linuxthreads_sig_cancel = { |
| 166 | "__pthread_sig_cancel", 1, 0, 0, 0, 0 |
| 167 | }; |
| 168 | struct linuxthreads_signal linuxthreads_sig_debug = { |
| 169 | "__pthread_sig_debug", 0, 0, 0, 0, 0 |
| 170 | }; |
| 171 | |
| 172 | /* Set by thread_db module when it takes over the thread_stratum. |
| 173 | In that case we must: |
| 174 | a) refrain from turning on the debug signal, and |
| 175 | b) refrain from calling add_thread. */ |
| 176 | |
| 177 | int using_thread_db = 0; |
| 178 | |
| 179 | /* A table of breakpoint locations, one per PID. */ |
| 180 | static struct linuxthreads_breakpoint { |
| 181 | CORE_ADDR pc; /* PC of breakpoint */ |
| 182 | int pid; /* pid of breakpoint */ |
| 183 | int step; /* whether the pc has been reached after sstep */ |
| 184 | } *linuxthreads_breakpoint_zombie; /* Zombie breakpoints array */ |
| 185 | static int linuxthreads_breakpoint_last; /* Last zombie breakpoint */ |
| 186 | |
| 187 | /* linuxthreads_{insert,remove}_breakpoint pass the breakpoint address |
| 188 | to {insert,remove}_breakpoint via this variable, since |
| 189 | iterate_active_threads doesn't provide any way to pass values |
| 190 | through to the worker function. */ |
| 191 | static CORE_ADDR linuxthreads_breakpoint_addr; |
| 192 | |
| 193 | #define REMOVE_BREAKPOINT_ZOMBIE(_i) \ |
| 194 | { \ |
| 195 | if ((_i) < linuxthreads_breakpoint_last) \ |
| 196 | linuxthreads_breakpoint_zombie[(_i)] = \ |
| 197 | linuxthreads_breakpoint_zombie[linuxthreads_breakpoint_last]; \ |
| 198 | linuxthreads_breakpoint_last--; \ |
| 199 | } |
| 200 | |
| 201 | |
| 202 | \f |
| 203 | #ifndef PTRACE_XFER_TYPE |
| 204 | #define PTRACE_XFER_TYPE int |
| 205 | #endif |
| 206 | /* Check to see if the given thread is alive. */ |
| 207 | static int |
| 208 | linuxthreads_thread_alive (pid) |
| 209 | int pid; |
| 210 | { |
| 211 | errno = 0; |
| 212 | return ptrace (PT_READ_U, pid, (PTRACE_ARG3_TYPE)0, 0) >= 0 || errno == 0; |
| 213 | } |
| 214 | |
| 215 | /* On detach(), find a SIGTRAP status. If stop is non-zero, find a |
| 216 | SIGSTOP one, too. |
| 217 | |
| 218 | Make sure PID is ready to run, and free of interference from our |
| 219 | efforts to debug it (e.g., pending SIGSTOP or SIGTRAP signals). If |
| 220 | STOP is zero, just look for a SIGTRAP. If STOP is non-zero, look |
| 221 | for a SIGSTOP, too. Return non-zero if PID is alive and ready to |
| 222 | run; return zero if PID is dead. |
| 223 | |
| 224 | PID may or may not be stopped at the moment, and we may or may not |
| 225 | have waited for it already. We check the linuxthreads_wait bag in |
| 226 | case we've already got a status for it. We may possibly wait for |
| 227 | it ourselves. |
| 228 | |
| 229 | PID may have signals waiting to be delivered. If they're caused by |
| 230 | our efforts to debug it, accept them with wait, but don't pass them |
| 231 | through to PID. Do pass all other signals through. */ |
| 232 | static int |
| 233 | linuxthreads_find_trap (pid, stop) |
| 234 | int pid; |
| 235 | int stop; |
| 236 | { |
| 237 | int i; |
| 238 | int rpid; |
| 239 | int status; |
| 240 | int found_stop = 0; |
| 241 | int found_trap = 0; |
| 242 | |
| 243 | /* PID may have any number of signals pending. The kernel will |
| 244 | report each of them to us via wait, and then it's up to us to |
| 245 | pass them along to the process via ptrace, if we so choose. |
| 246 | |
| 247 | We need to paw through the whole set until we've found a SIGTRAP |
| 248 | (or a SIGSTOP, if `stop' is set). We don't pass the SIGTRAP (or |
| 249 | SIGSTOP) through, but we do re-send all the others, so PID will |
| 250 | receive them when we resume it. */ |
| 251 | int *wstatus = alloca (LINUXTHREAD_NSIG * sizeof (int)); |
| 252 | int last = 0; |
| 253 | |
| 254 | /* Look at the pending status */ |
| 255 | for (i = linuxthreads_wait_last; i >= 0; i--) |
| 256 | if (linuxthreads_wait_pid[i] == pid) |
| 257 | { |
| 258 | status = linuxthreads_wait_status[i]; |
| 259 | |
| 260 | /* Delete the i'th member of the table. Since the table is |
| 261 | unordered, we can do this simply by copying the table's |
| 262 | last element to the i'th position, and shrinking the table |
| 263 | by one element. */ |
| 264 | if (i < linuxthreads_wait_last) |
| 265 | { |
| 266 | linuxthreads_wait_status[i] = |
| 267 | linuxthreads_wait_status[linuxthreads_wait_last]; |
| 268 | linuxthreads_wait_pid[i] = |
| 269 | linuxthreads_wait_pid[linuxthreads_wait_last]; |
| 270 | } |
| 271 | linuxthreads_wait_last--; |
| 272 | |
| 273 | if (!WIFSTOPPED(status)) /* Thread has died */ |
| 274 | return 0; |
| 275 | |
| 276 | if (WSTOPSIG(status) == SIGTRAP) |
| 277 | { |
| 278 | if (stop) |
| 279 | found_trap = 1; |
| 280 | else |
| 281 | return 1; |
| 282 | } |
| 283 | else if (WSTOPSIG(status) == SIGSTOP) |
| 284 | { |
| 285 | if (stop) |
| 286 | found_stop = 1; |
| 287 | } |
| 288 | else |
| 289 | { |
| 290 | wstatus[0] = status; |
| 291 | last = 1; |
| 292 | } |
| 293 | |
| 294 | break; |
| 295 | } |
| 296 | |
| 297 | if (stop) |
| 298 | { |
| 299 | /* Make sure that we'll find what we're looking for. */ |
| 300 | if (!found_trap) |
| 301 | { |
| 302 | kill (pid, SIGTRAP); |
| 303 | } |
| 304 | if (!found_stop) |
| 305 | { |
| 306 | kill (pid, SIGSTOP); |
| 307 | } |
| 308 | } |
| 309 | |
| 310 | /* Catch all status until SIGTRAP and optionally SIGSTOP show up. */ |
| 311 | for (;;) |
| 312 | { |
| 313 | /* resume the child every time... */ |
| 314 | child_resume (pid, 1, TARGET_SIGNAL_0); |
| 315 | |
| 316 | /* loop as long as errno == EINTR: |
| 317 | waitpid syscall may be aborted due to GDB receiving a signal. |
| 318 | FIXME: EINTR handling should no longer be necessary here, since |
| 319 | we now block SIGCHLD except in an explicit sigsuspend call. */ |
| 320 | |
| 321 | for (;;) |
| 322 | { |
| 323 | rpid = waitpid (pid, &status, __WCLONE); |
| 324 | if (rpid > 0) |
| 325 | { |
| 326 | break; |
| 327 | } |
| 328 | if (errno == EINTR) |
| 329 | { |
| 330 | continue; |
| 331 | } |
| 332 | |
| 333 | /* There are a few reasons the wait call above may have |
| 334 | failed. If the thread manager dies, its children get |
| 335 | reparented, and this interferes with GDB waiting for |
| 336 | them, in some cases. Another possibility is that the |
| 337 | initial thread was not cloned, so calling wait with |
| 338 | __WCLONE won't find it. I think neither of these should |
| 339 | occur in modern Linux kernels --- they don't seem to in |
| 340 | 2.0.36. */ |
| 341 | rpid = waitpid (pid, &status, 0); |
| 342 | if (rpid > 0) |
| 343 | { |
| 344 | break; |
| 345 | } |
| 346 | if (errno != EINTR) |
| 347 | perror_with_name ("find_trap/waitpid"); |
| 348 | } |
| 349 | |
| 350 | if (!WIFSTOPPED(status)) /* Thread has died */ |
| 351 | return 0; |
| 352 | |
| 353 | if (WSTOPSIG(status) == SIGTRAP) |
| 354 | if (!stop || found_stop) |
| 355 | break; |
| 356 | else |
| 357 | found_trap = 1; |
| 358 | else if (WSTOPSIG(status) != SIGSTOP) |
| 359 | wstatus[last++] = status; |
| 360 | else if (stop) |
| 361 | { |
| 362 | if (found_trap) |
| 363 | break; |
| 364 | else |
| 365 | found_stop = 1; |
| 366 | } |
| 367 | } |
| 368 | |
| 369 | /* Resend any other signals we noticed to the thread, to be received |
| 370 | when we continue it. */ |
| 371 | while (--last >= 0) |
| 372 | { |
| 373 | kill (pid, WSTOPSIG(wstatus[last])); |
| 374 | } |
| 375 | |
| 376 | return 1; |
| 377 | } |
| 378 | |
| 379 | /* Cleanup stub for save_inferior_pid. */ |
| 380 | static void |
| 381 | restore_inferior_pid (arg) |
| 382 | void *arg; |
| 383 | { |
| 384 | #if TARGET_PTR_BIT > TARGET_INT_BIT |
| 385 | inferior_pid = (int) ((long) arg); |
| 386 | #else |
| 387 | inferior_pid = (int) arg; |
| 388 | #endif |
| 389 | } |
| 390 | |
| 391 | /* Register a cleanup to restore the value of inferior_pid. */ |
| 392 | static struct cleanup * |
| 393 | save_inferior_pid () |
| 394 | { |
| 395 | #if TARGET_PTR_BIT > TARGET_INT_BIT |
| 396 | return make_cleanup (restore_inferior_pid, (void *) ((long) inferior_pid)); |
| 397 | #else |
| 398 | return make_cleanup (restore_inferior_pid, (void *) inferior_pid); |
| 399 | #endif |
| 400 | } |
| 401 | |
| 402 | static void |
| 403 | sigchld_handler (signo) |
| 404 | int signo; |
| 405 | { |
| 406 | /* This handler is used to get an EINTR while doing waitpid() |
| 407 | when an event is received */ |
| 408 | } |
| 409 | |
| 410 | /* Have we already collected a wait status for PID in the |
| 411 | linuxthreads_wait bag? */ |
| 412 | static int |
| 413 | linuxthreads_pending_status (pid) |
| 414 | int pid; |
| 415 | { |
| 416 | int i; |
| 417 | for (i = linuxthreads_wait_last; i >= 0; i--) |
| 418 | if (linuxthreads_wait_pid[i] == pid) |
| 419 | return 1; |
| 420 | return 0; |
| 421 | } |
| 422 | |
| 423 | \f |
| 424 | /* Internal linuxthreads signal management */ |
| 425 | |
| 426 | /* Check in OBJFILE for the variable that holds the number for signal SIG. |
| 427 | We assume that we've already found other LinuxThreads-ish variables |
| 428 | in OBJFILE, so we complain if it's required, but not there. |
| 429 | Return true iff things are okay. */ |
| 430 | static int |
| 431 | find_signal_var (sig, objfile) |
| 432 | struct linuxthreads_signal *sig; |
| 433 | struct objfile *objfile; |
| 434 | { |
| 435 | struct minimal_symbol *ms = lookup_minimal_symbol (sig->var, NULL, objfile); |
| 436 | |
| 437 | if (! ms) |
| 438 | { |
| 439 | if (sig->required) |
| 440 | { |
| 441 | fprintf_unfiltered (gdb_stderr, |
| 442 | "Unable to find linuxthreads symbol \"%s\"\n", |
| 443 | sig->var); |
| 444 | return 0; |
| 445 | } |
| 446 | else |
| 447 | { |
| 448 | sig->addr = 0; |
| 449 | return 1; |
| 450 | } |
| 451 | } |
| 452 | |
| 453 | sig->addr = SYMBOL_VALUE_ADDRESS (ms); |
| 454 | |
| 455 | return 1; |
| 456 | } |
| 457 | |
| 458 | static int |
| 459 | find_all_signal_vars (objfile) |
| 460 | struct objfile *objfile; |
| 461 | { |
| 462 | return ( find_signal_var (&linuxthreads_sig_restart, objfile) |
| 463 | && find_signal_var (&linuxthreads_sig_cancel, objfile) |
| 464 | && find_signal_var (&linuxthreads_sig_debug, objfile)); |
| 465 | } |
| 466 | |
| 467 | /* A struct complaint isn't appropriate here. */ |
| 468 | static int complained_cannot_determine_thread_signal_number = 0; |
| 469 | |
| 470 | /* Check to see if the variable holding the signal number for SIG has |
| 471 | been initialized yet. If it has, tell GDB to pass that signal |
| 472 | through to the inferior silently. */ |
| 473 | static void |
| 474 | check_signal_number (sig) |
| 475 | struct linuxthreads_signal *sig; |
| 476 | { |
| 477 | int num; |
| 478 | |
| 479 | if (sig->signal) |
| 480 | /* We already know this signal number. */ |
| 481 | return; |
| 482 | |
| 483 | if (! sig->addr) |
| 484 | /* We don't know the variable's address yet. */ |
| 485 | return; |
| 486 | |
| 487 | if (target_read_memory (sig->addr, (char *)&num, sizeof (num)) |
| 488 | != 0) |
| 489 | { |
| 490 | /* If this happens once, it'll probably happen for all the |
| 491 | signals, so only complain once. */ |
| 492 | if (! complained_cannot_determine_thread_signal_number) |
| 493 | warning ("Cannot determine thread signal number; " |
| 494 | "GDB may report spurious signals."); |
| 495 | complained_cannot_determine_thread_signal_number = 1; |
| 496 | return; |
| 497 | } |
| 498 | |
| 499 | if (num == 0) |
| 500 | /* It hasn't been initialized yet. */ |
| 501 | return; |
| 502 | |
| 503 | /* We know sig->signal was zero, and is becoming non-zero, so it's |
| 504 | okay to sample GDB's original settings. */ |
| 505 | sig->signal = num; |
| 506 | sig->stop = signal_stop_update (target_signal_from_host (num), 0); |
| 507 | sig->print = signal_print_update (target_signal_from_host (num), 0); |
| 508 | } |
| 509 | |
| 510 | void |
| 511 | check_all_signal_numbers () |
| 512 | { |
| 513 | /* If this isn't a LinuxThreads program, quit early. */ |
| 514 | if (! linuxthreads_max) |
| 515 | return; |
| 516 | |
| 517 | check_signal_number (&linuxthreads_sig_restart); |
| 518 | check_signal_number (&linuxthreads_sig_cancel); |
| 519 | check_signal_number (&linuxthreads_sig_debug); |
| 520 | |
| 521 | /* handle linuxthread exit */ |
| 522 | if (linuxthreads_sig_debug.signal |
| 523 | || linuxthreads_sig_restart.signal) |
| 524 | { |
| 525 | struct sigaction sact; |
| 526 | |
| 527 | sact.sa_handler = sigchld_handler; |
| 528 | sigemptyset(&sact.sa_mask); |
| 529 | sact.sa_flags = 0; |
| 530 | |
| 531 | if (linuxthreads_sig_debug.signal > 0) |
| 532 | sigaction(linuxthreads_sig_cancel.signal, &sact, NULL); |
| 533 | else |
| 534 | sigaction(linuxthreads_sig_restart.signal, &sact, NULL); |
| 535 | } |
| 536 | } |
| 537 | |
| 538 | |
| 539 | /* Restore GDB's original settings for SIG. |
| 540 | This should only be called when we're no longer sure if we're |
| 541 | talking to an executable that uses LinuxThreads, so we clear the |
| 542 | signal number and variable address too. */ |
| 543 | static void |
| 544 | restore_signal (sig) |
| 545 | struct linuxthreads_signal *sig; |
| 546 | { |
| 547 | if (! sig->signal) |
| 548 | return; |
| 549 | |
| 550 | /* We know sig->signal was non-zero, and is becoming zero, so it's |
| 551 | okay to restore GDB's original settings. */ |
| 552 | signal_stop_update (target_signal_from_host (sig->signal), sig->stop); |
| 553 | signal_print_update (target_signal_from_host (sig->signal), sig->print); |
| 554 | |
| 555 | sig->signal = 0; |
| 556 | sig->addr = 0; |
| 557 | } |
| 558 | |
| 559 | |
| 560 | /* Restore GDB's original settings for all LinuxThreads signals. |
| 561 | This should only be called when we're no longer sure if we're |
| 562 | talking to an executable that uses LinuxThreads, so we clear the |
| 563 | signal number and variable address too. */ |
| 564 | static void |
| 565 | restore_all_signals () |
| 566 | { |
| 567 | restore_signal (&linuxthreads_sig_restart); |
| 568 | restore_signal (&linuxthreads_sig_cancel); |
| 569 | restore_signal (&linuxthreads_sig_debug); |
| 570 | |
| 571 | /* If it happens again, we should complain again. */ |
| 572 | complained_cannot_determine_thread_signal_number = 0; |
| 573 | } |
| 574 | |
| 575 | |
| 576 | \f |
| 577 | |
| 578 | /* Apply FUNC to the pid of each active thread. This consults the |
| 579 | inferior's handle table to find active threads. |
| 580 | |
| 581 | If ALL is non-zero, process all threads. |
| 582 | If ALL is zero, skip threads with pending status. */ |
| 583 | static void |
| 584 | iterate_active_threads (func, all) |
| 585 | void (*func)(int); |
| 586 | int all; |
| 587 | { |
| 588 | CORE_ADDR descr; |
| 589 | int pid; |
| 590 | int i; |
| 591 | int num; |
| 592 | |
| 593 | read_memory (linuxthreads_num, (char *)&num, sizeof (int)); |
| 594 | |
| 595 | for (i = 0; i < linuxthreads_max && num > 0; i++) |
| 596 | { |
| 597 | read_memory (linuxthreads_handles + |
| 598 | linuxthreads_sizeof_handle * i + linuxthreads_offset_descr, |
| 599 | (char *)&descr, sizeof (void *)); |
| 600 | if (descr) |
| 601 | { |
| 602 | num--; |
| 603 | read_memory (descr + linuxthreads_offset_pid, |
| 604 | (char *)&pid, sizeof (pid_t)); |
| 605 | if (pid > 0 && pid != linuxthreads_manager_pid |
| 606 | && (all || (!linuxthreads_pending_status (pid)))) |
| 607 | (*func)(pid); |
| 608 | } |
| 609 | } |
| 610 | } |
| 611 | |
| 612 | /* Insert a thread breakpoint at linuxthreads_breakpoint_addr. |
| 613 | This is the worker function for linuxthreads_insert_breakpoint, |
| 614 | which passes it to iterate_active_threads. */ |
| 615 | static void |
| 616 | insert_breakpoint (pid) |
| 617 | int pid; |
| 618 | { |
| 619 | int j; |
| 620 | |
| 621 | /* Remove (if any) the positive zombie breakpoint. */ |
| 622 | for (j = linuxthreads_breakpoint_last; j >= 0; j--) |
| 623 | if (linuxthreads_breakpoint_zombie[j].pid == pid) |
| 624 | { |
| 625 | if ((linuxthreads_breakpoint_zombie[j].pc - DECR_PC_AFTER_BREAK |
| 626 | == linuxthreads_breakpoint_addr) |
| 627 | && !linuxthreads_breakpoint_zombie[j].step) |
| 628 | REMOVE_BREAKPOINT_ZOMBIE(j); |
| 629 | break; |
| 630 | } |
| 631 | } |
| 632 | |
| 633 | /* Note that we're about to remove a thread breakpoint at |
| 634 | linuxthreads_breakpoint_addr. |
| 635 | |
| 636 | This is the worker function for linuxthreads_remove_breakpoint, |
| 637 | which passes it to iterate_active_threads. The actual work of |
| 638 | overwriting the breakpoint instruction is done by |
| 639 | child_ops.to_remove_breakpoint; here, we simply create a zombie |
| 640 | breakpoint if the thread's PC is pointing at the breakpoint being |
| 641 | removed. */ |
| 642 | static void |
| 643 | remove_breakpoint (pid) |
| 644 | int pid; |
| 645 | { |
| 646 | int j; |
| 647 | |
| 648 | /* Insert a positive zombie breakpoint (if needed). */ |
| 649 | for (j = 0; j <= linuxthreads_breakpoint_last; j++) |
| 650 | if (linuxthreads_breakpoint_zombie[j].pid == pid) |
| 651 | break; |
| 652 | |
| 653 | if (in_thread_list (pid) && linuxthreads_thread_alive (pid)) |
| 654 | { |
| 655 | CORE_ADDR pc = read_pc_pid (pid); |
| 656 | if (linuxthreads_breakpoint_addr == pc - DECR_PC_AFTER_BREAK |
| 657 | && j > linuxthreads_breakpoint_last) |
| 658 | { |
| 659 | linuxthreads_breakpoint_zombie[j].pid = pid; |
| 660 | linuxthreads_breakpoint_zombie[j].pc = pc; |
| 661 | linuxthreads_breakpoint_zombie[j].step = 0; |
| 662 | linuxthreads_breakpoint_last++; |
| 663 | } |
| 664 | } |
| 665 | } |
| 666 | |
| 667 | /* Kill a thread */ |
| 668 | static void |
| 669 | kill_thread (pid) |
| 670 | int pid; |
| 671 | { |
| 672 | if (in_thread_list (pid)) |
| 673 | { |
| 674 | ptrace (PT_KILL, pid, (PTRACE_ARG3_TYPE) 0, 0); |
| 675 | } |
| 676 | else |
| 677 | { |
| 678 | kill (pid, SIGKILL); |
| 679 | } |
| 680 | } |
| 681 | |
| 682 | /* Resume a thread */ |
| 683 | static void |
| 684 | resume_thread (pid) |
| 685 | int pid; |
| 686 | { |
| 687 | if (pid != inferior_pid |
| 688 | && in_thread_list (pid) |
| 689 | && linuxthreads_thread_alive (pid)) |
| 690 | { |
| 691 | if (pid == linuxthreads_step_pid) |
| 692 | { |
| 693 | child_resume (pid, 1, linuxthreads_step_signo); |
| 694 | } |
| 695 | else |
| 696 | { |
| 697 | child_resume (pid, 0, TARGET_SIGNAL_0); |
| 698 | } |
| 699 | } |
| 700 | } |
| 701 | |
| 702 | /* Detach a thread */ |
| 703 | static void |
| 704 | detach_thread (pid) |
| 705 | int pid; |
| 706 | { |
| 707 | if (in_thread_list (pid) && linuxthreads_thread_alive (pid)) |
| 708 | { |
| 709 | /* Remove pending SIGTRAP and SIGSTOP */ |
| 710 | linuxthreads_find_trap (pid, 1); |
| 711 | |
| 712 | inferior_pid = pid; |
| 713 | detach (TARGET_SIGNAL_0); |
| 714 | inferior_pid = linuxthreads_manager_pid; |
| 715 | } |
| 716 | } |
| 717 | |
| 718 | /* Attach a thread */ |
| 719 | void |
| 720 | attach_thread (pid) |
| 721 | int pid; |
| 722 | { |
| 723 | if (ptrace (PT_ATTACH, pid, (PTRACE_ARG3_TYPE) 0, 0) != 0) |
| 724 | perror_with_name ("attach_thread"); |
| 725 | } |
| 726 | |
| 727 | /* Stop a thread */ |
| 728 | static void |
| 729 | stop_thread (pid) |
| 730 | int pid; |
| 731 | { |
| 732 | if (pid != inferior_pid) |
| 733 | { |
| 734 | if (in_thread_list (pid)) |
| 735 | { |
| 736 | kill (pid, SIGSTOP); |
| 737 | } |
| 738 | else if (ptrace (PT_ATTACH, pid, (PTRACE_ARG3_TYPE) 0, 0) == 0) |
| 739 | { |
| 740 | if (!linuxthreads_attach_pending) |
| 741 | printf_filtered ("[New %s]\n", target_pid_to_str (pid)); |
| 742 | add_thread (pid); |
| 743 | if (linuxthreads_sig_debug.signal) |
| 744 | { |
| 745 | /* After a new thread in glibc 2.1 signals gdb its existence, |
| 746 | it suspends itself and wait for linuxthreads_sig_restart, |
| 747 | now we can wake it up. */ |
| 748 | kill (pid, linuxthreads_sig_restart.signal); |
| 749 | } |
| 750 | } |
| 751 | else |
| 752 | perror_with_name ("ptrace in stop_thread"); |
| 753 | } |
| 754 | } |
| 755 | |
| 756 | /* Wait for a thread */ |
| 757 | static void |
| 758 | wait_thread (pid) |
| 759 | int pid; |
| 760 | { |
| 761 | int status; |
| 762 | int rpid; |
| 763 | |
| 764 | if (pid != inferior_pid && in_thread_list (pid)) |
| 765 | { |
| 766 | /* loop as long as errno == EINTR: |
| 767 | waitpid syscall may be aborted if GDB receives a signal. |
| 768 | FIXME: EINTR handling should no longer be necessary here, since |
| 769 | we now block SIGCHLD except during an explicit sigsuspend call. */ |
| 770 | for (;;) |
| 771 | { |
| 772 | /* Get first pid status. */ |
| 773 | rpid = waitpid(pid, &status, __WCLONE); |
| 774 | if (rpid > 0) |
| 775 | { |
| 776 | break; |
| 777 | } |
| 778 | if (errno == EINTR) |
| 779 | { |
| 780 | continue; |
| 781 | } |
| 782 | |
| 783 | /* There are two reasons this might have failed: |
| 784 | |
| 785 | 1) PID is the initial thread, which wasn't cloned, so |
| 786 | passing the __WCLONE flag to waitpid prevented us from |
| 787 | finding it. |
| 788 | |
| 789 | 2) The manager thread is the parent of all but the |
| 790 | initial thread; if it dies, the children will all be |
| 791 | reparented to init, which will wait for them. This means |
| 792 | our call to waitpid won't find them. |
| 793 | |
| 794 | Actually, based on a casual look at the 2.0.36 kernel |
| 795 | code, I don't think either of these cases happen. But I |
| 796 | don't have things set up for remotely debugging the |
| 797 | kernel, so I'm not sure. And perhaps older kernels |
| 798 | didn't work. */ |
| 799 | rpid = waitpid(pid, &status, 0); |
| 800 | if (rpid > 0) |
| 801 | { |
| 802 | break; |
| 803 | } |
| 804 | if (errno != EINTR && linuxthreads_thread_alive (pid)) |
| 805 | perror_with_name ("wait_thread/waitpid"); |
| 806 | |
| 807 | /* the thread is dead. */ |
| 808 | return; |
| 809 | } |
| 810 | if (!WIFSTOPPED(status) || WSTOPSIG(status) != SIGSTOP) |
| 811 | { |
| 812 | linuxthreads_wait_pid[++linuxthreads_wait_last] = pid; |
| 813 | linuxthreads_wait_status[linuxthreads_wait_last] = status; |
| 814 | } |
| 815 | } |
| 816 | } |
| 817 | |
| 818 | /* Walk through the linuxthreads handles in order to detect all |
| 819 | threads and stop them */ |
| 820 | static void |
| 821 | update_stop_threads (test_pid) |
| 822 | int test_pid; |
| 823 | { |
| 824 | struct cleanup *old_chain = NULL; |
| 825 | |
| 826 | check_all_signal_numbers (); |
| 827 | |
| 828 | if (linuxthreads_manager_pid == 0) |
| 829 | { |
| 830 | if (linuxthreads_manager) |
| 831 | { |
| 832 | if (test_pid > 0 && test_pid != inferior_pid) |
| 833 | { |
| 834 | old_chain = save_inferior_pid (); |
| 835 | inferior_pid = test_pid; |
| 836 | } |
| 837 | read_memory (linuxthreads_manager, |
| 838 | (char *)&linuxthreads_manager_pid, sizeof (pid_t)); |
| 839 | } |
| 840 | if (linuxthreads_initial) |
| 841 | { |
| 842 | if (test_pid > 0 && test_pid != inferior_pid) |
| 843 | { |
| 844 | old_chain = save_inferior_pid (); |
| 845 | inferior_pid = test_pid; |
| 846 | } |
| 847 | read_memory(linuxthreads_initial, |
| 848 | (char *)&linuxthreads_initial_pid, sizeof (pid_t)); |
| 849 | } |
| 850 | } |
| 851 | |
| 852 | if (linuxthreads_manager_pid != 0) |
| 853 | { |
| 854 | if (old_chain == NULL && test_pid > 0 && |
| 855 | test_pid != inferior_pid && linuxthreads_thread_alive (test_pid)) |
| 856 | { |
| 857 | old_chain = save_inferior_pid (); |
| 858 | inferior_pid = test_pid; |
| 859 | } |
| 860 | |
| 861 | if (linuxthreads_thread_alive (inferior_pid)) |
| 862 | { |
| 863 | if (test_pid > 0) |
| 864 | { |
| 865 | if (test_pid != linuxthreads_manager_pid |
| 866 | && !linuxthreads_pending_status (linuxthreads_manager_pid)) |
| 867 | { |
| 868 | stop_thread (linuxthreads_manager_pid); |
| 869 | wait_thread (linuxthreads_manager_pid); |
| 870 | } |
| 871 | if (!in_thread_list (test_pid)) |
| 872 | { |
| 873 | if (!linuxthreads_attach_pending) |
| 874 | printf_filtered ("[New %s]\n", |
| 875 | target_pid_to_str (test_pid)); |
| 876 | add_thread (test_pid); |
| 877 | if (linuxthreads_sig_debug.signal |
| 878 | && inferior_pid == test_pid) |
| 879 | { |
| 880 | /* After a new thread in glibc 2.1 signals gdb its |
| 881 | existence, it suspends itself and wait for |
| 882 | linuxthreads_sig_restart, now we can wake it up. */ |
| 883 | kill (test_pid, linuxthreads_sig_restart.signal); |
| 884 | } |
| 885 | } |
| 886 | } |
| 887 | iterate_active_threads (stop_thread, 0); |
| 888 | iterate_active_threads (wait_thread, 0); |
| 889 | } |
| 890 | } |
| 891 | |
| 892 | if (old_chain != NULL) |
| 893 | do_cleanups (old_chain); |
| 894 | } |
| 895 | |
| 896 | /* This routine is called whenever a new symbol table is read in, or |
| 897 | when all symbol tables are removed. linux-thread event handling |
| 898 | can only be initialized when we find the right variables in |
| 899 | libpthread.so. Since it's a shared library, those variables don't |
| 900 | show up until the library gets mapped and the symbol table is read |
| 901 | in. */ |
| 902 | |
| 903 | /* This new_objfile event is now managed by a chained function pointer. |
| 904 | * It is the callee's responsability to call the next client on the chain. |
| 905 | */ |
| 906 | |
| 907 | /* Saved pointer to previous owner of the new_objfile event. */ |
| 908 | static void (*target_new_objfile_chain) PARAMS ((struct objfile *)); |
| 909 | |
| 910 | void |
| 911 | linuxthreads_new_objfile (objfile) |
| 912 | struct objfile *objfile; |
| 913 | { |
| 914 | struct minimal_symbol *ms; |
| 915 | |
| 916 | /* Call predecessor on chain, if any. |
| 917 | Calling the new module first allows it to dominate, |
| 918 | if it finds its compatible libraries. */ |
| 919 | |
| 920 | if (target_new_objfile_chain) |
| 921 | target_new_objfile_chain (objfile); |
| 922 | |
| 923 | if (!objfile) |
| 924 | { |
| 925 | /* We're starting an entirely new executable, so we can no |
| 926 | longer be sure that it uses LinuxThreads. Restore the signal |
| 927 | flags to their original states. */ |
| 928 | restore_all_signals (); |
| 929 | |
| 930 | /* Indicate that we don't know anything's address any more. */ |
| 931 | linuxthreads_max = 0; |
| 932 | |
| 933 | goto quit; |
| 934 | } |
| 935 | |
| 936 | /* If we've already found our variables in another objfile, don't |
| 937 | bother looking for them again. */ |
| 938 | if (linuxthreads_max) |
| 939 | goto quit; |
| 940 | |
| 941 | if (! lookup_minimal_symbol ("__pthread_initial_thread", NULL, objfile)) |
| 942 | /* This object file isn't the pthreads library. */ |
| 943 | goto quit; |
| 944 | |
| 945 | if ((ms = lookup_minimal_symbol ("__pthread_threads_debug", |
| 946 | NULL, objfile)) == NULL) |
| 947 | { |
| 948 | /* The debugging-aware libpthreads is not present in this objfile */ |
| 949 | warning ("\ |
| 950 | This program seems to use POSIX threads, but the thread library used\n\ |
| 951 | does not support debugging. This may make using GDB difficult. Don't\n\ |
| 952 | set breakpoints or single-step through code that might be executed by\n\ |
| 953 | any thread other than the main thread."); |
| 954 | goto quit; |
| 955 | } |
| 956 | linuxthreads_debug = SYMBOL_VALUE_ADDRESS (ms); |
| 957 | |
| 958 | /* Read internal structures configuration */ |
| 959 | if ((ms = lookup_minimal_symbol ("__pthread_sizeof_handle", |
| 960 | NULL, objfile)) == NULL |
| 961 | || target_read_memory (SYMBOL_VALUE_ADDRESS (ms), |
| 962 | (char *)&linuxthreads_sizeof_handle, |
| 963 | sizeof (linuxthreads_sizeof_handle)) != 0) |
| 964 | { |
| 965 | fprintf_unfiltered (gdb_stderr, |
| 966 | "Unable to find linuxthreads symbol \"%s\"\n", |
| 967 | "__pthread_sizeof_handle"); |
| 968 | goto quit; |
| 969 | } |
| 970 | |
| 971 | if ((ms = lookup_minimal_symbol ("__pthread_offsetof_descr", |
| 972 | NULL, objfile)) == NULL |
| 973 | || target_read_memory (SYMBOL_VALUE_ADDRESS (ms), |
| 974 | (char *)&linuxthreads_offset_descr, |
| 975 | sizeof (linuxthreads_offset_descr)) != 0) |
| 976 | { |
| 977 | fprintf_unfiltered (gdb_stderr, |
| 978 | "Unable to find linuxthreads symbol \"%s\"\n", |
| 979 | "__pthread_offsetof_descr"); |
| 980 | goto quit; |
| 981 | } |
| 982 | |
| 983 | if ((ms = lookup_minimal_symbol ("__pthread_offsetof_pid", |
| 984 | NULL, objfile)) == NULL |
| 985 | || target_read_memory (SYMBOL_VALUE_ADDRESS (ms), |
| 986 | (char *)&linuxthreads_offset_pid, |
| 987 | sizeof (linuxthreads_offset_pid)) != 0) |
| 988 | { |
| 989 | fprintf_unfiltered (gdb_stderr, |
| 990 | "Unable to find linuxthreads symbol \"%s\"\n", |
| 991 | "__pthread_offsetof_pid"); |
| 992 | goto quit; |
| 993 | } |
| 994 | |
| 995 | if (! find_all_signal_vars (objfile)) |
| 996 | goto quit; |
| 997 | |
| 998 | /* Read adresses of internal structures to access */ |
| 999 | if ((ms = lookup_minimal_symbol ("__pthread_handles", |
| 1000 | NULL, objfile)) == NULL) |
| 1001 | { |
| 1002 | fprintf_unfiltered (gdb_stderr, |
| 1003 | "Unable to find linuxthreads symbol \"%s\"\n", |
| 1004 | "__pthread_handles"); |
| 1005 | goto quit; |
| 1006 | } |
| 1007 | linuxthreads_handles = SYMBOL_VALUE_ADDRESS (ms); |
| 1008 | |
| 1009 | if ((ms = lookup_minimal_symbol ("__pthread_handles_num", |
| 1010 | NULL, objfile)) == NULL) |
| 1011 | { |
| 1012 | fprintf_unfiltered (gdb_stderr, |
| 1013 | "Unable to find linuxthreads symbol \"%s\"\n", |
| 1014 | "__pthread_handles_num"); |
| 1015 | goto quit; |
| 1016 | } |
| 1017 | linuxthreads_num = SYMBOL_VALUE_ADDRESS (ms); |
| 1018 | |
| 1019 | if ((ms = lookup_minimal_symbol ("__pthread_manager_thread", |
| 1020 | NULL, objfile)) == NULL) |
| 1021 | { |
| 1022 | fprintf_unfiltered (gdb_stderr, |
| 1023 | "Unable to find linuxthreads symbol \"%s\"\n", |
| 1024 | "__pthread_manager_thread"); |
| 1025 | goto quit; |
| 1026 | } |
| 1027 | linuxthreads_manager = SYMBOL_VALUE_ADDRESS (ms) + linuxthreads_offset_pid; |
| 1028 | |
| 1029 | if ((ms = lookup_minimal_symbol ("__pthread_initial_thread", |
| 1030 | NULL, objfile)) == NULL) |
| 1031 | { |
| 1032 | fprintf_unfiltered (gdb_stderr, |
| 1033 | "Unable to find linuxthreads symbol \"%s\"\n", |
| 1034 | "__pthread_initial_thread"); |
| 1035 | goto quit; |
| 1036 | } |
| 1037 | linuxthreads_initial = SYMBOL_VALUE_ADDRESS (ms) + linuxthreads_offset_pid; |
| 1038 | |
| 1039 | /* Search for this last, so it won't be set to a non-zero value unless |
| 1040 | we successfully found all the symbols above. */ |
| 1041 | if ((ms = lookup_minimal_symbol ("__pthread_threads_max", |
| 1042 | NULL, objfile)) == NULL |
| 1043 | || target_read_memory (SYMBOL_VALUE_ADDRESS (ms), |
| 1044 | (char *)&linuxthreads_max, |
| 1045 | sizeof (linuxthreads_max)) != 0) |
| 1046 | { |
| 1047 | fprintf_unfiltered (gdb_stderr, |
| 1048 | "Unable to find linuxthreads symbol \"%s\"\n", |
| 1049 | "__pthread_threads_max"); |
| 1050 | goto quit; |
| 1051 | } |
| 1052 | |
| 1053 | /* Allocate gdb internal structures */ |
| 1054 | linuxthreads_wait_pid = |
| 1055 | (int *) xmalloc (sizeof (int) * (linuxthreads_max + 1)); |
| 1056 | linuxthreads_wait_status = |
| 1057 | (int *) xmalloc (sizeof (int) * (linuxthreads_max + 1)); |
| 1058 | linuxthreads_breakpoint_zombie = (struct linuxthreads_breakpoint *) |
| 1059 | xmalloc (sizeof (struct linuxthreads_breakpoint) * (linuxthreads_max + 1)); |
| 1060 | |
| 1061 | if (inferior_pid && |
| 1062 | !linuxthreads_attach_pending && |
| 1063 | !using_thread_db) /* suppressed by thread_db module */ |
| 1064 | { |
| 1065 | int on = 1; |
| 1066 | |
| 1067 | target_write_memory (linuxthreads_debug, (char *)&on, sizeof (on)); |
| 1068 | linuxthreads_attach_pending = 1; |
| 1069 | update_stop_threads (inferior_pid); |
| 1070 | linuxthreads_attach_pending = 0; |
| 1071 | } |
| 1072 | |
| 1073 | check_all_signal_numbers (); |
| 1074 | |
| 1075 | quit: |
| 1076 | } |
| 1077 | |
| 1078 | /* If we have switched threads from a one that stopped at breakpoint, |
| 1079 | return 1 otherwise 0. */ |
| 1080 | |
| 1081 | int |
| 1082 | linuxthreads_prepare_to_proceed (step) |
| 1083 | int step; |
| 1084 | { |
| 1085 | if (!linuxthreads_max |
| 1086 | || !linuxthreads_manager_pid |
| 1087 | || !linuxthreads_breakpoint_pid |
| 1088 | || !breakpoint_here_p (read_pc_pid (linuxthreads_breakpoint_pid))) |
| 1089 | return 0; |
| 1090 | |
| 1091 | if (step) |
| 1092 | { |
| 1093 | /* Mark the current inferior as single stepping process. */ |
| 1094 | linuxthreads_step_pid = inferior_pid; |
| 1095 | } |
| 1096 | |
| 1097 | linuxthreads_inferior_pid = linuxthreads_breakpoint_pid; |
| 1098 | return linuxthreads_breakpoint_pid; |
| 1099 | } |
| 1100 | |
| 1101 | /* Convert a pid to printable form. */ |
| 1102 | |
| 1103 | char * |
| 1104 | linuxthreads_pid_to_str (pid) |
| 1105 | int pid; |
| 1106 | { |
| 1107 | static char buf[100]; |
| 1108 | |
| 1109 | sprintf (buf, "%s %d%s", linuxthreads_max ? "Thread" : "Pid", pid, |
| 1110 | (pid == linuxthreads_manager_pid) ? " (manager thread)" |
| 1111 | : (pid == linuxthreads_initial_pid) ? " (initial thread)" |
| 1112 | : ""); |
| 1113 | |
| 1114 | return buf; |
| 1115 | } |
| 1116 | |
| 1117 | /* Attach to process PID, then initialize for debugging it |
| 1118 | and wait for the trace-trap that results from attaching. */ |
| 1119 | |
| 1120 | static void |
| 1121 | linuxthreads_attach (args, from_tty) |
| 1122 | char *args; |
| 1123 | int from_tty; |
| 1124 | { |
| 1125 | if (!args) |
| 1126 | error_no_arg ("process-id to attach"); |
| 1127 | |
| 1128 | push_target (&linuxthreads_ops); |
| 1129 | linuxthreads_breakpoints_inserted = 1; |
| 1130 | linuxthreads_breakpoint_last = -1; |
| 1131 | linuxthreads_wait_last = -1; |
| 1132 | WSETSTOP (linux_exit_status, 0); |
| 1133 | |
| 1134 | child_ops.to_attach (args, from_tty); |
| 1135 | |
| 1136 | if (linuxthreads_max) |
| 1137 | linuxthreads_attach_pending = 1; |
| 1138 | } |
| 1139 | |
| 1140 | /* Take a program previously attached to and detaches it. |
| 1141 | The program resumes execution and will no longer stop |
| 1142 | on signals, etc. We'd better not have left any breakpoints |
| 1143 | in the program or it'll die when it hits one. For this |
| 1144 | to work, it may be necessary for the process to have been |
| 1145 | previously attached. It *might* work if the program was |
| 1146 | started via the normal ptrace (PTRACE_TRACEME). */ |
| 1147 | |
| 1148 | static void |
| 1149 | linuxthreads_detach (args, from_tty) |
| 1150 | char *args; |
| 1151 | int from_tty; |
| 1152 | { |
| 1153 | if (linuxthreads_max) |
| 1154 | { |
| 1155 | int i; |
| 1156 | int pid; |
| 1157 | int off = 0; |
| 1158 | target_write_memory (linuxthreads_debug, (char *)&off, sizeof (off)); |
| 1159 | |
| 1160 | /* Walk through linuxthreads array in order to detach known threads. */ |
| 1161 | if (linuxthreads_manager_pid != 0) |
| 1162 | { |
| 1163 | /* Get rid of all positive zombie breakpoints. */ |
| 1164 | for (i = 0; i <= linuxthreads_breakpoint_last; i++) |
| 1165 | { |
| 1166 | if (linuxthreads_breakpoint_zombie[i].step) |
| 1167 | continue; |
| 1168 | |
| 1169 | pid = linuxthreads_breakpoint_zombie[i].pid; |
| 1170 | if (!linuxthreads_thread_alive (pid)) |
| 1171 | continue; |
| 1172 | |
| 1173 | if (linuxthreads_breakpoint_zombie[i].pc != read_pc_pid (pid)) |
| 1174 | continue; |
| 1175 | |
| 1176 | /* Continue in STEP mode until the thread pc has moved or |
| 1177 | until SIGTRAP is found on the same PC. */ |
| 1178 | if (linuxthreads_find_trap (pid, 0) |
| 1179 | && linuxthreads_breakpoint_zombie[i].pc == read_pc_pid (pid)) |
| 1180 | write_pc_pid (linuxthreads_breakpoint_zombie[i].pc |
| 1181 | - DECR_PC_AFTER_BREAK, pid); |
| 1182 | } |
| 1183 | |
| 1184 | /* Detach thread after thread. */ |
| 1185 | inferior_pid = linuxthreads_manager_pid; |
| 1186 | iterate_active_threads (detach_thread, 1); |
| 1187 | |
| 1188 | /* Remove pending SIGTRAP and SIGSTOP */ |
| 1189 | linuxthreads_find_trap (inferior_pid, 1); |
| 1190 | |
| 1191 | linuxthreads_wait_last = -1; |
| 1192 | WSETSTOP (linux_exit_status, 0); |
| 1193 | } |
| 1194 | |
| 1195 | linuxthreads_inferior_pid = 0; |
| 1196 | linuxthreads_breakpoint_pid = 0; |
| 1197 | linuxthreads_step_pid = 0; |
| 1198 | linuxthreads_step_signo = TARGET_SIGNAL_0; |
| 1199 | linuxthreads_manager_pid = 0; |
| 1200 | linuxthreads_initial_pid = 0; |
| 1201 | linuxthreads_attach_pending = 0; |
| 1202 | init_thread_list (); /* Destroy thread info */ |
| 1203 | } |
| 1204 | |
| 1205 | child_ops.to_detach (args, from_tty); |
| 1206 | |
| 1207 | unpush_target (&linuxthreads_ops); |
| 1208 | } |
| 1209 | |
| 1210 | /* Resume execution of process PID. If STEP is nozero, then |
| 1211 | just single step it. If SIGNAL is nonzero, restart it with that |
| 1212 | signal activated. */ |
| 1213 | |
| 1214 | static void |
| 1215 | linuxthreads_resume (pid, step, signo) |
| 1216 | int pid; |
| 1217 | int step; |
| 1218 | enum target_signal signo; |
| 1219 | { |
| 1220 | if (!linuxthreads_max || stop_soon_quietly || linuxthreads_manager_pid == 0) |
| 1221 | { |
| 1222 | child_ops.to_resume (pid, step, signo); |
| 1223 | } |
| 1224 | else |
| 1225 | { |
| 1226 | int rpid; |
| 1227 | if (linuxthreads_inferior_pid) |
| 1228 | { |
| 1229 | /* Prepare resume of the last thread that hit a breakpoint */ |
| 1230 | linuxthreads_breakpoints_inserted = 0; |
| 1231 | rpid = linuxthreads_inferior_pid; |
| 1232 | linuxthreads_step_signo = signo; |
| 1233 | } |
| 1234 | else |
| 1235 | { |
| 1236 | struct cleanup *old_chain = NULL; |
| 1237 | int i; |
| 1238 | |
| 1239 | if (pid < 0) |
| 1240 | { |
| 1241 | linuxthreads_step_pid = step ? inferior_pid : 0; |
| 1242 | linuxthreads_step_signo = signo; |
| 1243 | rpid = inferior_pid; |
| 1244 | } |
| 1245 | else |
| 1246 | rpid = pid; |
| 1247 | |
| 1248 | if (pid < 0 || !step) |
| 1249 | { |
| 1250 | linuxthreads_breakpoints_inserted = 1; |
| 1251 | |
| 1252 | /* Walk through linuxthreads array in order to resume threads */ |
| 1253 | if (pid >= 0 && inferior_pid != pid) |
| 1254 | { |
| 1255 | old_chain = save_inferior_pid (); |
| 1256 | inferior_pid = pid; |
| 1257 | } |
| 1258 | |
| 1259 | iterate_active_threads (resume_thread, 0); |
| 1260 | if (linuxthreads_manager_pid != inferior_pid |
| 1261 | && !linuxthreads_pending_status (linuxthreads_manager_pid)) |
| 1262 | resume_thread (linuxthreads_manager_pid); |
| 1263 | } |
| 1264 | else |
| 1265 | linuxthreads_breakpoints_inserted = 0; |
| 1266 | |
| 1267 | /* Deal with zombie breakpoint */ |
| 1268 | for (i = 0; i <= linuxthreads_breakpoint_last; i++) |
| 1269 | if (linuxthreads_breakpoint_zombie[i].pid == rpid) |
| 1270 | { |
| 1271 | if (linuxthreads_breakpoint_zombie[i].pc != read_pc_pid (rpid)) |
| 1272 | { |
| 1273 | /* The current pc is out of zombie breakpoint. */ |
| 1274 | REMOVE_BREAKPOINT_ZOMBIE(i); |
| 1275 | } |
| 1276 | break; |
| 1277 | } |
| 1278 | |
| 1279 | if (old_chain != NULL) |
| 1280 | do_cleanups (old_chain); |
| 1281 | } |
| 1282 | |
| 1283 | /* Resume initial thread. */ |
| 1284 | /* [unles it has a wait event pending] */ |
| 1285 | if (!linuxthreads_pending_status (rpid)) |
| 1286 | { |
| 1287 | child_ops.to_resume (rpid, step, signo); |
| 1288 | } |
| 1289 | } |
| 1290 | } |
| 1291 | |
| 1292 | /* Abstract out the child_wait functionality. */ |
| 1293 | int |
| 1294 | linux_child_wait (pid, rpid, status) |
| 1295 | int pid; |
| 1296 | int *rpid; |
| 1297 | int *status; |
| 1298 | { |
| 1299 | int save_errno; |
| 1300 | |
| 1301 | /* Note: inftarg has these inside the loop. */ |
| 1302 | set_sigint_trap (); /* Causes SIGINT to be passed on to the |
| 1303 | attached process. */ |
| 1304 | set_sigio_trap (); |
| 1305 | |
| 1306 | errno = save_errno = 0; |
| 1307 | for (;;) |
| 1308 | { |
| 1309 | errno = 0; |
| 1310 | *rpid = waitpid (pid, status, __WCLONE | WNOHANG); |
| 1311 | save_errno = errno; |
| 1312 | |
| 1313 | if (*rpid > 0) |
| 1314 | { |
| 1315 | /* Got an event -- break out */ |
| 1316 | break; |
| 1317 | } |
| 1318 | if (errno == EINTR) /* interrupted by signal, try again */ |
| 1319 | { |
| 1320 | continue; |
| 1321 | } |
| 1322 | |
| 1323 | errno = 0; |
| 1324 | *rpid = waitpid (pid, status, WNOHANG); |
| 1325 | if (*rpid > 0) |
| 1326 | { |
| 1327 | /* Got an event -- break out */ |
| 1328 | break; |
| 1329 | } |
| 1330 | if (errno == EINTR) |
| 1331 | { |
| 1332 | continue; |
| 1333 | } |
| 1334 | if (errno != 0 && save_errno != 0) |
| 1335 | { |
| 1336 | break; |
| 1337 | } |
| 1338 | sigsuspend(&linuxthreads_block_mask); |
| 1339 | } |
| 1340 | clear_sigio_trap (); |
| 1341 | clear_sigint_trap (); |
| 1342 | |
| 1343 | return errno ? errno : save_errno; |
| 1344 | } |
| 1345 | |
| 1346 | |
| 1347 | /* Wait for any threads to stop. We may have to convert PID from a thread id |
| 1348 | to a LWP id, and vice versa on the way out. */ |
| 1349 | |
| 1350 | static int |
| 1351 | linuxthreads_wait (pid, ourstatus) |
| 1352 | int pid; |
| 1353 | struct target_waitstatus *ourstatus; |
| 1354 | { |
| 1355 | int status; |
| 1356 | int rpid; |
| 1357 | int i; |
| 1358 | int last; |
| 1359 | int *wstatus; |
| 1360 | |
| 1361 | if (linuxthreads_max && !linuxthreads_breakpoints_inserted) |
| 1362 | wstatus = alloca (LINUXTHREAD_NSIG * sizeof (int)); |
| 1363 | |
| 1364 | /* See if the inferior has chosen values for its signals yet. By |
| 1365 | checking for them here, we can be sure we've updated GDB's signal |
| 1366 | handling table before the inferior ever gets one of them. (Well, |
| 1367 | before we notice, anyway.) */ |
| 1368 | check_all_signal_numbers (); |
| 1369 | |
| 1370 | for (;;) |
| 1371 | { |
| 1372 | if (!linuxthreads_max) |
| 1373 | rpid = 0; |
| 1374 | else if (!linuxthreads_breakpoints_inserted) |
| 1375 | { |
| 1376 | if (linuxthreads_inferior_pid) |
| 1377 | pid = linuxthreads_inferior_pid; |
| 1378 | else if (pid < 0) |
| 1379 | pid = inferior_pid; |
| 1380 | last = rpid = 0; |
| 1381 | } |
| 1382 | else if (pid < 0 && linuxthreads_wait_last >= 0) |
| 1383 | { |
| 1384 | status = linuxthreads_wait_status[linuxthreads_wait_last]; |
| 1385 | rpid = linuxthreads_wait_pid[linuxthreads_wait_last--]; |
| 1386 | } |
| 1387 | else if (pid > 0 && linuxthreads_pending_status (pid)) |
| 1388 | { |
| 1389 | for (i = linuxthreads_wait_last; i >= 0; i--) |
| 1390 | if (linuxthreads_wait_pid[i] == pid) |
| 1391 | break; |
| 1392 | if (i < 0) |
| 1393 | rpid = 0; |
| 1394 | else |
| 1395 | { |
| 1396 | status = linuxthreads_wait_status[i]; |
| 1397 | rpid = pid; |
| 1398 | if (i < linuxthreads_wait_last) |
| 1399 | { |
| 1400 | linuxthreads_wait_status[i] = |
| 1401 | linuxthreads_wait_status[linuxthreads_wait_last]; |
| 1402 | linuxthreads_wait_pid[i] = |
| 1403 | linuxthreads_wait_pid[linuxthreads_wait_last]; |
| 1404 | } |
| 1405 | linuxthreads_wait_last--; |
| 1406 | } |
| 1407 | } |
| 1408 | else |
| 1409 | rpid = 0; |
| 1410 | |
| 1411 | if (rpid == 0) |
| 1412 | { |
| 1413 | int save_errno; |
| 1414 | |
| 1415 | save_errno = linux_child_wait (pid, &rpid, &status); |
| 1416 | |
| 1417 | if (rpid == -1) |
| 1418 | { |
| 1419 | if (WIFEXITED(linuxthreads_exit_status)) |
| 1420 | { |
| 1421 | store_waitstatus (ourstatus, linuxthreads_exit_status); |
| 1422 | return inferior_pid; |
| 1423 | } |
| 1424 | else |
| 1425 | { |
| 1426 | fprintf_unfiltered |
| 1427 | (gdb_stderr, "Child process unexpectedly missing: %s.\n", |
| 1428 | safe_strerror (save_errno)); |
| 1429 | /* Claim it exited with unknown signal. */ |
| 1430 | ourstatus->kind = TARGET_WAITKIND_SIGNALLED; |
| 1431 | ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN; |
| 1432 | return -1; |
| 1433 | } |
| 1434 | } |
| 1435 | |
| 1436 | /* We have now gotten a new event from waitpid above. */ |
| 1437 | |
| 1438 | /* Signals arrive in any order. So get all signals until |
| 1439 | SIGTRAP and resend previous ones to be held after. */ |
| 1440 | if (linuxthreads_max |
| 1441 | && !linuxthreads_breakpoints_inserted |
| 1442 | && WIFSTOPPED(status)) |
| 1443 | if (WSTOPSIG(status) == SIGTRAP) |
| 1444 | { |
| 1445 | while (--last >= 0) |
| 1446 | { |
| 1447 | kill (rpid, WSTOPSIG(wstatus[last])); |
| 1448 | } |
| 1449 | |
| 1450 | /* insert negative zombie breakpoint */ |
| 1451 | for (i = 0; i <= linuxthreads_breakpoint_last; i++) |
| 1452 | if (linuxthreads_breakpoint_zombie[i].pid == rpid) |
| 1453 | break; |
| 1454 | if (i > linuxthreads_breakpoint_last) |
| 1455 | { |
| 1456 | linuxthreads_breakpoint_zombie[i].pid = rpid; |
| 1457 | linuxthreads_breakpoint_last++; |
| 1458 | } |
| 1459 | linuxthreads_breakpoint_zombie[i].pc = read_pc_pid (rpid); |
| 1460 | linuxthreads_breakpoint_zombie[i].step = 1; |
| 1461 | } |
| 1462 | else |
| 1463 | { |
| 1464 | if (WSTOPSIG(status) != SIGSTOP) |
| 1465 | { |
| 1466 | for (i = 0; i < last; i++) |
| 1467 | if (wstatus[i] == status) |
| 1468 | break; |
| 1469 | if (i >= last) |
| 1470 | { |
| 1471 | wstatus[last++] = status; |
| 1472 | } |
| 1473 | } |
| 1474 | child_resume (rpid, 1, TARGET_SIGNAL_0); |
| 1475 | continue; |
| 1476 | } |
| 1477 | if (linuxthreads_inferior_pid) |
| 1478 | linuxthreads_inferior_pid = 0; |
| 1479 | } |
| 1480 | |
| 1481 | if (linuxthreads_max && !stop_soon_quietly) |
| 1482 | { |
| 1483 | if (linuxthreads_max |
| 1484 | && WIFSTOPPED(status) |
| 1485 | && WSTOPSIG(status) == SIGSTOP) |
| 1486 | { |
| 1487 | /* Skip SIGSTOP signals. */ |
| 1488 | if (!linuxthreads_pending_status (rpid)) |
| 1489 | { |
| 1490 | if (linuxthreads_step_pid == rpid) |
| 1491 | { |
| 1492 | child_resume (rpid, 1, linuxthreads_step_signo); |
| 1493 | } |
| 1494 | else |
| 1495 | { |
| 1496 | child_resume (rpid, 0, TARGET_SIGNAL_0); |
| 1497 | } |
| 1498 | } |
| 1499 | continue; |
| 1500 | } |
| 1501 | |
| 1502 | /* Do no report exit status of cloned threads. */ |
| 1503 | if (WIFEXITED(status)) |
| 1504 | { |
| 1505 | if (rpid == linuxthreads_initial_pid) |
| 1506 | linuxthreads_exit_status = status; |
| 1507 | |
| 1508 | /* Remove any zombie breakpoint. */ |
| 1509 | for (i = 0; i <= linuxthreads_breakpoint_last; i++) |
| 1510 | if (linuxthreads_breakpoint_zombie[i].pid == rpid) |
| 1511 | { |
| 1512 | REMOVE_BREAKPOINT_ZOMBIE(i); |
| 1513 | break; |
| 1514 | } |
| 1515 | if (pid > 0) |
| 1516 | pid = -1; |
| 1517 | continue; |
| 1518 | } |
| 1519 | |
| 1520 | /* Deal with zombie breakpoint */ |
| 1521 | for (i = 0; i <= linuxthreads_breakpoint_last; i++) |
| 1522 | if (linuxthreads_breakpoint_zombie[i].pid == rpid) |
| 1523 | break; |
| 1524 | |
| 1525 | if (i <= linuxthreads_breakpoint_last) |
| 1526 | { |
| 1527 | /* There is a potential zombie breakpoint */ |
| 1528 | if (WIFEXITED(status) |
| 1529 | || linuxthreads_breakpoint_zombie[i].pc != read_pc_pid (rpid)) |
| 1530 | { |
| 1531 | /* The current pc is out of zombie breakpoint. */ |
| 1532 | REMOVE_BREAKPOINT_ZOMBIE(i); |
| 1533 | } |
| 1534 | else if (!linuxthreads_breakpoint_zombie[i].step |
| 1535 | && WIFSTOPPED(status) && WSTOPSIG(status) == SIGTRAP) |
| 1536 | { |
| 1537 | /* This is a real one ==> decrement PC and restart. */ |
| 1538 | write_pc_pid (linuxthreads_breakpoint_zombie[i].pc |
| 1539 | - DECR_PC_AFTER_BREAK, rpid); |
| 1540 | if (linuxthreads_step_pid == rpid) |
| 1541 | { |
| 1542 | child_resume (rpid, 1, linuxthreads_step_signo); |
| 1543 | } |
| 1544 | else |
| 1545 | { |
| 1546 | child_resume (rpid, 0, TARGET_SIGNAL_0); |
| 1547 | } |
| 1548 | continue; |
| 1549 | } |
| 1550 | } |
| 1551 | |
| 1552 | /* Walk through linuxthreads array in order to stop them */ |
| 1553 | if (linuxthreads_breakpoints_inserted) |
| 1554 | update_stop_threads (rpid); |
| 1555 | |
| 1556 | } |
| 1557 | else if (rpid != inferior_pid) |
| 1558 | continue; |
| 1559 | |
| 1560 | store_waitstatus (ourstatus, status); |
| 1561 | |
| 1562 | if (linuxthreads_attach_pending && !stop_soon_quietly) |
| 1563 | { |
| 1564 | int on = 1; |
| 1565 | if (!using_thread_db) |
| 1566 | { |
| 1567 | target_write_memory (linuxthreads_debug, |
| 1568 | (char *) &on, sizeof (on)); |
| 1569 | update_stop_threads (rpid); |
| 1570 | } |
| 1571 | linuxthreads_attach_pending = 0; |
| 1572 | } |
| 1573 | |
| 1574 | if (linuxthreads_breakpoints_inserted |
| 1575 | && WIFSTOPPED(status) |
| 1576 | && WSTOPSIG(status) == SIGTRAP) |
| 1577 | linuxthreads_breakpoint_pid = rpid; |
| 1578 | else if (linuxthreads_breakpoint_pid) |
| 1579 | linuxthreads_breakpoint_pid = 0; |
| 1580 | |
| 1581 | return rpid; |
| 1582 | } |
| 1583 | } |
| 1584 | |
| 1585 | /* Fork an inferior process, and start debugging it with ptrace. */ |
| 1586 | |
| 1587 | static void |
| 1588 | linuxthreads_create_inferior (exec_file, allargs, env) |
| 1589 | char *exec_file; |
| 1590 | char *allargs; |
| 1591 | char **env; |
| 1592 | { |
| 1593 | if (!exec_file && !exec_bfd) |
| 1594 | { |
| 1595 | error ("No executable file specified.\n\ |
| 1596 | Use the \"file\" or \"exec-file\" command."); |
| 1597 | return; |
| 1598 | } |
| 1599 | |
| 1600 | push_target (&linuxthreads_ops); |
| 1601 | linuxthreads_breakpoints_inserted = 1; |
| 1602 | linuxthreads_breakpoint_last = -1; |
| 1603 | linuxthreads_wait_last = -1; |
| 1604 | WSETSTOP (linux_exit_status, 0); |
| 1605 | |
| 1606 | if (linuxthreads_max) |
| 1607 | linuxthreads_attach_pending = 1; |
| 1608 | |
| 1609 | child_ops.to_create_inferior (exec_file, allargs, env); |
| 1610 | } |
| 1611 | |
| 1612 | void |
| 1613 | linuxthreads_discard_global_state () |
| 1614 | { |
| 1615 | linuxthreads_inferior_pid = 0; |
| 1616 | linuxthreads_breakpoint_pid = 0; |
| 1617 | linuxthreads_step_pid = 0; |
| 1618 | linuxthreads_step_signo = TARGET_SIGNAL_0; |
| 1619 | linuxthreads_manager_pid = 0; |
| 1620 | linuxthreads_initial_pid = 0; |
| 1621 | linuxthreads_attach_pending = 0; |
| 1622 | linuxthreads_max = 0; |
| 1623 | } |
| 1624 | |
| 1625 | /* Clean up after the inferior dies. */ |
| 1626 | |
| 1627 | static void |
| 1628 | linuxthreads_mourn_inferior () |
| 1629 | { |
| 1630 | if (linuxthreads_max) |
| 1631 | { |
| 1632 | int off = 0; |
| 1633 | target_write_memory (linuxthreads_debug, (char *)&off, sizeof (off)); |
| 1634 | |
| 1635 | linuxthreads_discard_global_state (); |
| 1636 | init_thread_list(); /* Destroy thread info */ |
| 1637 | } |
| 1638 | |
| 1639 | child_ops.to_mourn_inferior (); |
| 1640 | |
| 1641 | unpush_target (&linuxthreads_ops); |
| 1642 | } |
| 1643 | |
| 1644 | /* Kill the inferior process */ |
| 1645 | |
| 1646 | static void |
| 1647 | linuxthreads_kill () |
| 1648 | { |
| 1649 | int rpid; |
| 1650 | int status; |
| 1651 | |
| 1652 | if (inferior_pid == 0) |
| 1653 | return; |
| 1654 | |
| 1655 | if (linuxthreads_max && linuxthreads_manager_pid != 0) |
| 1656 | { |
| 1657 | /* Remove all threads status. */ |
| 1658 | inferior_pid = linuxthreads_manager_pid; |
| 1659 | iterate_active_threads (kill_thread, 1); |
| 1660 | } |
| 1661 | |
| 1662 | kill_thread (inferior_pid); |
| 1663 | |
| 1664 | #if 0 |
| 1665 | /* doing_quit_force solves a real problem, but I think a properly |
| 1666 | placed call to catch_errors would do the trick much more cleanly. */ |
| 1667 | if (doing_quit_force >= 0) |
| 1668 | { |
| 1669 | if (linuxthreads_max && linuxthreads_manager_pid != 0) |
| 1670 | { |
| 1671 | /* Wait for thread to complete */ |
| 1672 | while ((rpid = waitpid (-1, &status, __WCLONE)) > 0) |
| 1673 | if (!WIFEXITED(status)) |
| 1674 | kill_thread (rpid); |
| 1675 | |
| 1676 | while ((rpid = waitpid (-1, &status, 0)) > 0) |
| 1677 | if (!WIFEXITED(status)) |
| 1678 | kill_thread (rpid); |
| 1679 | } |
| 1680 | else |
| 1681 | while ((rpid = waitpid (inferior_pid, &status, 0)) > 0) |
| 1682 | if (!WIFEXITED(status)) |
| 1683 | ptrace (PT_KILL, inferior_pid, (PTRACE_ARG3_TYPE) 0, 0); |
| 1684 | } |
| 1685 | #endif |
| 1686 | |
| 1687 | /* Wait for all threads. */ |
| 1688 | do |
| 1689 | { |
| 1690 | rpid = waitpid (-1, &status, __WCLONE | WNOHANG); |
| 1691 | } |
| 1692 | while (rpid > 0 || errno == EINTR); |
| 1693 | /* FIXME: should no longer need to handle EINTR here. */ |
| 1694 | |
| 1695 | do |
| 1696 | { |
| 1697 | rpid = waitpid (-1, &status, WNOHANG); |
| 1698 | } |
| 1699 | while (rpid > 0 || errno == EINTR); |
| 1700 | /* FIXME: should no longer need to handle EINTR here. */ |
| 1701 | |
| 1702 | linuxthreads_mourn_inferior (); |
| 1703 | } |
| 1704 | |
| 1705 | /* Insert a breakpoint */ |
| 1706 | |
| 1707 | static int |
| 1708 | linuxthreads_insert_breakpoint (addr, contents_cache) |
| 1709 | CORE_ADDR addr; |
| 1710 | char *contents_cache; |
| 1711 | { |
| 1712 | if (linuxthreads_max && linuxthreads_manager_pid != 0) |
| 1713 | { |
| 1714 | linuxthreads_breakpoint_addr = addr; |
| 1715 | iterate_active_threads (insert_breakpoint, 1); |
| 1716 | insert_breakpoint (linuxthreads_manager_pid); |
| 1717 | } |
| 1718 | |
| 1719 | return child_ops.to_insert_breakpoint (addr, contents_cache); |
| 1720 | } |
| 1721 | |
| 1722 | /* Remove a breakpoint */ |
| 1723 | |
| 1724 | static int |
| 1725 | linuxthreads_remove_breakpoint (addr, contents_cache) |
| 1726 | CORE_ADDR addr; |
| 1727 | char *contents_cache; |
| 1728 | { |
| 1729 | if (linuxthreads_max && linuxthreads_manager_pid != 0) |
| 1730 | { |
| 1731 | linuxthreads_breakpoint_addr = addr; |
| 1732 | iterate_active_threads (remove_breakpoint, 1); |
| 1733 | remove_breakpoint (linuxthreads_manager_pid); |
| 1734 | } |
| 1735 | |
| 1736 | return child_ops.to_remove_breakpoint (addr, contents_cache); |
| 1737 | } |
| 1738 | |
| 1739 | /* Mark our target-struct as eligible for stray "run" and "attach" commands. */ |
| 1740 | |
| 1741 | static int |
| 1742 | linuxthreads_can_run () |
| 1743 | { |
| 1744 | return child_suppress_run; |
| 1745 | } |
| 1746 | |
| 1747 | \f |
| 1748 | static void |
| 1749 | init_linuxthreads_ops () |
| 1750 | { |
| 1751 | linuxthreads_ops.to_shortname = "linuxthreads"; |
| 1752 | linuxthreads_ops.to_longname = "LINUX threads and pthread."; |
| 1753 | linuxthreads_ops.to_doc = "LINUX threads and pthread support."; |
| 1754 | linuxthreads_ops.to_attach = linuxthreads_attach; |
| 1755 | linuxthreads_ops.to_detach = linuxthreads_detach; |
| 1756 | linuxthreads_ops.to_resume = linuxthreads_resume; |
| 1757 | linuxthreads_ops.to_wait = linuxthreads_wait; |
| 1758 | linuxthreads_ops.to_kill = linuxthreads_kill; |
| 1759 | linuxthreads_ops.to_can_run = linuxthreads_can_run; |
| 1760 | linuxthreads_ops.to_stratum = thread_stratum; |
| 1761 | linuxthreads_ops.to_insert_breakpoint = linuxthreads_insert_breakpoint; |
| 1762 | linuxthreads_ops.to_remove_breakpoint = linuxthreads_remove_breakpoint; |
| 1763 | linuxthreads_ops.to_create_inferior = linuxthreads_create_inferior; |
| 1764 | linuxthreads_ops.to_mourn_inferior = linuxthreads_mourn_inferior; |
| 1765 | linuxthreads_ops.to_thread_alive = linuxthreads_thread_alive; |
| 1766 | linuxthreads_ops.to_pid_to_str = linuxthreads_pid_to_str; |
| 1767 | linuxthreads_ops.to_magic = OPS_MAGIC; |
| 1768 | } |
| 1769 | |
| 1770 | void |
| 1771 | _initialize_linuxthreads () |
| 1772 | { |
| 1773 | struct sigaction sact; |
| 1774 | sigset_t linuxthreads_wait_mask; /* sigset with SIGCHLD */ |
| 1775 | |
| 1776 | init_linuxthreads_ops (); |
| 1777 | add_target (&linuxthreads_ops); |
| 1778 | child_suppress_run = 1; |
| 1779 | |
| 1780 | /* Hook onto the "new_objfile" event. |
| 1781 | * If someone else is already hooked onto the event, |
| 1782 | * then make sure he will be called after we are. |
| 1783 | */ |
| 1784 | target_new_objfile_chain = target_new_objfile_hook; |
| 1785 | target_new_objfile_hook = linuxthreads_new_objfile; |
| 1786 | |
| 1787 | /* Attach SIGCHLD handler */ |
| 1788 | sact.sa_handler = sigchld_handler; |
| 1789 | sigemptyset (&sact.sa_mask); |
| 1790 | sact.sa_flags = 0; |
| 1791 | sigaction (SIGCHLD, &sact, NULL); |
| 1792 | |
| 1793 | /* initialize SIGCHLD mask */ |
| 1794 | sigemptyset (&linuxthreads_wait_mask); |
| 1795 | sigaddset (&linuxthreads_wait_mask, SIGCHLD); |
| 1796 | |
| 1797 | /* Use SIG_BLOCK to block receipt of SIGCHLD. |
| 1798 | The block_mask will allow us to wait for this signal explicitly. */ |
| 1799 | sigprocmask(SIG_BLOCK, |
| 1800 | &linuxthreads_wait_mask, |
| 1801 | &linuxthreads_block_mask); |
| 1802 | /* Make sure that linuxthreads_block_mask is not blocking SIGCHLD */ |
| 1803 | sigdelset (&linuxthreads_block_mask, SIGCHLD); |
| 1804 | } |