1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791
|
/* GNU/Linux native-dependent code for debugging multiple forks.
Copyright (C) 2005-2015 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "arch-utils.h"
#include "inferior.h"
#include "infrun.h"
#include "regcache.h"
#include "gdbcmd.h"
#include "infcall.h"
#include "objfiles.h"
#include "linux-fork.h"
#include "linux-nat.h"
#include "gdbthread.h"
#include "source.h"
#include "nat/gdb_ptrace.h"
#include "gdb_wait.h"
#include <dirent.h>
#include <ctype.h>
struct fork_info *fork_list;
static int highest_fork_num;
/* Prevent warning from -Wmissing-prototypes. */
extern void _initialize_linux_fork (void);
/* Fork list data structure: */
struct fork_info
{
struct fork_info *next;
ptid_t ptid;
ptid_t parent_ptid;
int num; /* Convenient handle (GDB fork id). */
struct regcache *savedregs; /* Convenient for info fork, saves
having to actually switch contexts. */
int clobber_regs; /* True if we should restore saved regs. */
off_t *filepos; /* Set of open file descriptors' offsets. */
int maxfd;
};
/* Fork list methods: */
int
forks_exist_p (void)
{
return (fork_list != NULL);
}
/* Add a fork to the internal fork list. */
struct fork_info *
add_fork (pid_t pid)
{
struct fork_info *fp;
if (fork_list == NULL && pid != ptid_get_pid (inferior_ptid))
{
/* Special case -- if this is the first fork in the list
(the list is hitherto empty), and if this new fork is
NOT the current inferior_ptid, then add inferior_ptid
first, as a special zeroeth fork id. */
highest_fork_num = -1;
add_fork (ptid_get_pid (inferior_ptid)); /* safe recursion */
}
fp = XCNEW (struct fork_info);
fp->ptid = ptid_build (pid, pid, 0);
fp->num = ++highest_fork_num;
fp->next = fork_list;
fork_list = fp;
return fp;
}
static void
free_fork (struct fork_info *fp)
{
/* Notes on step-resume breakpoints: since this is a concern for
threads, let's convince ourselves that it's not a concern for
forks. There are two ways for a fork_info to be created. First,
by the checkpoint command, in which case we're at a gdb prompt
and there can't be any step-resume breakpoint. Second, by a fork
in the user program, in which case we *may* have stepped into the
fork call, but regardless of whether we follow the parent or the
child, we will return to the same place and the step-resume
breakpoint, if any, will take care of itself as usual. And
unlike threads, we do not save a private copy of the step-resume
breakpoint -- so we're OK. */
if (fp)
{
if (fp->savedregs)
regcache_xfree (fp->savedregs);
if (fp->filepos)
xfree (fp->filepos);
xfree (fp);
}
}
static void
delete_fork (ptid_t ptid)
{
struct fork_info *fp, *fpprev;
fpprev = NULL;
linux_nat_forget_process (ptid_get_pid (ptid));
for (fp = fork_list; fp; fpprev = fp, fp = fp->next)
if (ptid_equal (fp->ptid, ptid))
break;
if (!fp)
return;
if (fpprev)
fpprev->next = fp->next;
else
fork_list = fp->next;
free_fork (fp);
/* Special case: if there is now only one process in the list,
and if it is (hopefully!) the current inferior_ptid, then
remove it, leaving the list empty -- we're now down to the
default case of debugging a single process. */
if (fork_list != NULL && fork_list->next == NULL &&
ptid_equal (fork_list->ptid, inferior_ptid))
{
/* Last fork -- delete from list and handle as solo process
(should be a safe recursion). */
delete_fork (inferior_ptid);
}
}
/* Find a fork_info by matching PTID. */
static struct fork_info *
find_fork_ptid (ptid_t ptid)
{
struct fork_info *fp;
for (fp = fork_list; fp; fp = fp->next)
if (ptid_equal (fp->ptid, ptid))
return fp;
return NULL;
}
/* Find a fork_info by matching ID. */
static struct fork_info *
find_fork_id (int num)
{
struct fork_info *fp;
for (fp = fork_list; fp; fp = fp->next)
if (fp->num == num)
return fp;
return NULL;
}
/* Find a fork_info by matching pid. */
extern struct fork_info *
find_fork_pid (pid_t pid)
{
struct fork_info *fp;
for (fp = fork_list; fp; fp = fp->next)
if (pid == ptid_get_pid (fp->ptid))
return fp;
return NULL;
}
static ptid_t
fork_id_to_ptid (int num)
{
struct fork_info *fork = find_fork_id (num);
if (fork)
return fork->ptid;
else
return pid_to_ptid (-1);
}
static void
init_fork_list (void)
{
struct fork_info *fp, *fpnext;
if (!fork_list)
return;
for (fp = fork_list; fp; fp = fpnext)
{
fpnext = fp->next;
free_fork (fp);
}
fork_list = NULL;
}
/* Fork list <-> gdb interface. */
/* Utility function for fork_load/fork_save.
Calls lseek in the (current) inferior process. */
static off_t
call_lseek (int fd, off_t offset, int whence)
{
char exp[80];
snprintf (&exp[0], sizeof (exp), "lseek (%d, %ld, %d)",
fd, (long) offset, whence);
return (off_t) parse_and_eval_long (&exp[0]);
}
/* Load infrun state for the fork PTID. */
static void
fork_load_infrun_state (struct fork_info *fp)
{
extern void nullify_last_target_wait_ptid ();
int i;
linux_nat_switch_fork (fp->ptid);
if (fp->savedregs && fp->clobber_regs)
regcache_cpy (get_current_regcache (), fp->savedregs);
registers_changed ();
reinit_frame_cache ();
stop_pc = regcache_read_pc (get_current_regcache ());
nullify_last_target_wait_ptid ();
/* Now restore the file positions of open file descriptors. */
if (fp->filepos)
{
for (i = 0; i <= fp->maxfd; i++)
if (fp->filepos[i] != (off_t) -1)
call_lseek (i, fp->filepos[i], SEEK_SET);
/* NOTE: I can get away with using SEEK_SET and SEEK_CUR because
this is native-only. If it ever has to be cross, we'll have
to rethink this. */
}
}
/* Save infrun state for the fork PTID.
Exported for use by linux child_follow_fork. */
static void
fork_save_infrun_state (struct fork_info *fp, int clobber_regs)
{
char path[PATH_MAX];
struct dirent *de;
DIR *d;
if (fp->savedregs)
regcache_xfree (fp->savedregs);
fp->savedregs = regcache_dup (get_current_regcache ());
fp->clobber_regs = clobber_regs;
if (clobber_regs)
{
/* Now save the 'state' (file position) of all open file descriptors.
Unfortunately fork does not take care of that for us... */
snprintf (path, PATH_MAX, "/proc/%ld/fd",
(long) ptid_get_pid (fp->ptid));
if ((d = opendir (path)) != NULL)
{
long tmp;
fp->maxfd = 0;
while ((de = readdir (d)) != NULL)
{
/* Count open file descriptors (actually find highest
numbered). */
tmp = strtol (&de->d_name[0], NULL, 10);
if (fp->maxfd < tmp)
fp->maxfd = tmp;
}
/* Allocate array of file positions. */
fp->filepos = XRESIZEVEC (off_t, fp->filepos, fp->maxfd + 1);
/* Initialize to -1 (invalid). */
for (tmp = 0; tmp <= fp->maxfd; tmp++)
fp->filepos[tmp] = -1;
/* Now find actual file positions. */
rewinddir (d);
while ((de = readdir (d)) != NULL)
if (isdigit (de->d_name[0]))
{
tmp = strtol (&de->d_name[0], NULL, 10);
fp->filepos[tmp] = call_lseek (tmp, 0, SEEK_CUR);
}
closedir (d);
}
}
}
/* Kill 'em all, let God sort 'em out... */
void
linux_fork_killall (void)
{
/* Walk list and kill every pid. No need to treat the
current inferior_ptid as special (we do not return a
status for it) -- however any process may be a child
or a parent, so may get a SIGCHLD from a previously
killed child. Wait them all out. */
struct fork_info *fp;
pid_t pid, ret;
int status;
for (fp = fork_list; fp; fp = fp->next)
{
pid = ptid_get_pid (fp->ptid);
do {
/* Use SIGKILL instead of PTRACE_KILL because the former works even
if the thread is running, while the later doesn't. */
kill (pid, SIGKILL);
ret = waitpid (pid, &status, 0);
/* We might get a SIGCHLD instead of an exit status. This is
aggravated by the first kill above - a child has just
died. MVS comment cut-and-pasted from linux-nat. */
} while (ret == pid && WIFSTOPPED (status));
}
init_fork_list (); /* Clear list, prepare to start fresh. */
}
/* The current inferior_ptid has exited, but there are other viable
forks to debug. Delete the exiting one and context-switch to the
first available. */
void
linux_fork_mourn_inferior (void)
{
/* Wait just one more time to collect the inferior's exit status.
Do not check whether this succeeds though, since we may be
dealing with a process that we attached to. Such a process will
only report its exit status to its original parent. */
int status;
waitpid (ptid_get_pid (inferior_ptid), &status, 0);
/* OK, presumably inferior_ptid is the one who has exited.
We need to delete that one from the fork_list, and switch
to the next available fork. */
delete_fork (inferior_ptid);
/* There should still be a fork - if there's only one left,
delete_fork won't remove it, because we haven't updated
inferior_ptid yet. */
gdb_assert (fork_list);
fork_load_infrun_state (fork_list);
printf_filtered (_("[Switching to %s]\n"),
target_pid_to_str (inferior_ptid));
/* If there's only one fork, switch back to non-fork mode. */
if (fork_list->next == NULL)
delete_fork (inferior_ptid);
}
/* The current inferior_ptid is being detached, but there are other
viable forks to debug. Detach and delete it and context-switch to
the first available. */
void
linux_fork_detach (const char *args, int from_tty)
{
/* OK, inferior_ptid is the one we are detaching from. We need to
delete it from the fork_list, and switch to the next available
fork. */
if (ptrace (PTRACE_DETACH, ptid_get_pid (inferior_ptid), 0, 0))
error (_("Unable to detach %s"), target_pid_to_str (inferior_ptid));
delete_fork (inferior_ptid);
/* There should still be a fork - if there's only one left,
delete_fork won't remove it, because we haven't updated
inferior_ptid yet. */
gdb_assert (fork_list);
fork_load_infrun_state (fork_list);
if (from_tty)
printf_filtered (_("[Switching to %s]\n"),
target_pid_to_str (inferior_ptid));
/* If there's only one fork, switch back to non-fork mode. */
if (fork_list->next == NULL)
delete_fork (inferior_ptid);
}
static void
inferior_call_waitpid_cleanup (void *fp)
{
struct fork_info *oldfp = (struct fork_info *) fp;
if (oldfp)
{
/* Switch back to inferior_ptid. */
remove_breakpoints ();
fork_load_infrun_state (oldfp);
insert_breakpoints ();
}
}
static int
inferior_call_waitpid (ptid_t pptid, int pid)
{
struct objfile *waitpid_objf;
struct value *waitpid_fn = NULL;
struct value *argv[4], *retv;
struct gdbarch *gdbarch = get_current_arch ();
struct fork_info *oldfp = NULL, *newfp = NULL;
struct cleanup *old_cleanup;
int ret = -1;
if (!ptid_equal (pptid, inferior_ptid))
{
/* Switch to pptid. */
oldfp = find_fork_ptid (inferior_ptid);
gdb_assert (oldfp != NULL);
newfp = find_fork_ptid (pptid);
gdb_assert (newfp != NULL);
fork_save_infrun_state (oldfp, 1);
remove_breakpoints ();
fork_load_infrun_state (newfp);
insert_breakpoints ();
}
old_cleanup = make_cleanup (inferior_call_waitpid_cleanup, oldfp);
/* Get the waitpid_fn. */
if (lookup_minimal_symbol ("waitpid", NULL, NULL).minsym != NULL)
waitpid_fn = find_function_in_inferior ("waitpid", &waitpid_objf);
if (!waitpid_fn
&& lookup_minimal_symbol ("_waitpid", NULL, NULL).minsym != NULL)
waitpid_fn = find_function_in_inferior ("_waitpid", &waitpid_objf);
if (!waitpid_fn)
goto out;
/* Get the argv. */
argv[0] = value_from_longest (builtin_type (gdbarch)->builtin_int, pid);
argv[1] = value_from_pointer (builtin_type (gdbarch)->builtin_data_ptr, 0);
argv[2] = value_from_longest (builtin_type (gdbarch)->builtin_int, 0);
argv[3] = 0;
retv = call_function_by_hand (waitpid_fn, 3, argv);
if (value_as_long (retv) < 0)
goto out;
ret = 0;
out:
do_cleanups (old_cleanup);
return ret;
}
/* Fork list <-> user interface. */
static void
delete_checkpoint_command (char *args, int from_tty)
{
ptid_t ptid, pptid;
struct fork_info *fi;
if (!args || !*args)
error (_("Requires argument (checkpoint id to delete)"));
ptid = fork_id_to_ptid (parse_and_eval_long (args));
if (ptid_equal (ptid, minus_one_ptid))
error (_("No such checkpoint id, %s"), args);
if (ptid_equal (ptid, inferior_ptid))
error (_("\
Please switch to another checkpoint before deleting the current one"));
if (ptrace (PTRACE_KILL, ptid_get_pid (ptid), 0, 0))
error (_("Unable to kill pid %s"), target_pid_to_str (ptid));
fi = find_fork_ptid (ptid);
gdb_assert (fi);
pptid = fi->parent_ptid;
if (from_tty)
printf_filtered (_("Killed %s\n"), target_pid_to_str (ptid));
delete_fork (ptid);
/* If fi->parent_ptid is not a part of lwp but it's a part of checkpoint
list, waitpid the ptid.
If fi->parent_ptid is a part of lwp and it is stoped, waitpid the
ptid. */
if ((!find_thread_ptid (pptid) && find_fork_ptid (pptid))
|| (find_thread_ptid (pptid) && is_stopped (pptid)))
{
if (inferior_call_waitpid (pptid, ptid_get_pid (ptid)))
warning (_("Unable to wait pid %s"), target_pid_to_str (ptid));
}
}
static void
detach_checkpoint_command (char *args, int from_tty)
{
ptid_t ptid;
if (!args || !*args)
error (_("Requires argument (checkpoint id to detach)"));
ptid = fork_id_to_ptid (parse_and_eval_long (args));
if (ptid_equal (ptid, minus_one_ptid))
error (_("No such checkpoint id, %s"), args);
if (ptid_equal (ptid, inferior_ptid))
error (_("\
Please switch to another checkpoint before detaching the current one"));
if (ptrace (PTRACE_DETACH, ptid_get_pid (ptid), 0, 0))
error (_("Unable to detach %s"), target_pid_to_str (ptid));
if (from_tty)
printf_filtered (_("Detached %s\n"), target_pid_to_str (ptid));
delete_fork (ptid);
}
/* Print information about currently known checkpoints. */
static void
info_checkpoints_command (char *arg, int from_tty)
{
struct gdbarch *gdbarch = get_current_arch ();
struct symtab_and_line sal;
struct fork_info *fp;
ULONGEST pc;
int requested = -1;
struct fork_info *printed = NULL;
if (arg && *arg)
requested = (int) parse_and_eval_long (arg);
for (fp = fork_list; fp; fp = fp->next)
{
if (requested > 0 && fp->num != requested)
continue;
printed = fp;
if (ptid_equal (fp->ptid, inferior_ptid))
{
printf_filtered ("* ");
pc = regcache_read_pc (get_current_regcache ());
}
else
{
printf_filtered (" ");
pc = regcache_read_pc (fp->savedregs);
}
printf_filtered ("%d %s", fp->num, target_pid_to_str (fp->ptid));
if (fp->num == 0)
printf_filtered (_(" (main process)"));
printf_filtered (_(" at "));
fputs_filtered (paddress (gdbarch, pc), gdb_stdout);
sal = find_pc_line (pc, 0);
if (sal.symtab)
printf_filtered (_(", file %s"),
symtab_to_filename_for_display (sal.symtab));
if (sal.line)
printf_filtered (_(", line %d"), sal.line);
if (!sal.symtab && !sal.line)
{
struct bound_minimal_symbol msym;
msym = lookup_minimal_symbol_by_pc (pc);
if (msym.minsym)
printf_filtered (", <%s>", MSYMBOL_LINKAGE_NAME (msym.minsym));
}
putchar_filtered ('\n');
}
if (printed == NULL)
{
if (requested > 0)
printf_filtered (_("No checkpoint number %d.\n"), requested);
else
printf_filtered (_("No checkpoints.\n"));
}
}
/* The PID of the process we're checkpointing. */
static int checkpointing_pid = 0;
int
linux_fork_checkpointing_p (int pid)
{
return (checkpointing_pid == pid);
}
/* Callback for iterate over threads. Used to check whether
the current inferior is multi-threaded. Returns true as soon
as it sees the second thread of the current inferior. */
static int
inf_has_multiple_thread_cb (struct thread_info *tp, void *data)
{
int *count_p = (int *) data;
if (current_inferior ()->pid == ptid_get_pid (tp->ptid))
(*count_p)++;
/* Stop the iteration if multiple threads have been detected. */
return *count_p > 1;
}
/* Return true if the current inferior is multi-threaded. */
static int
inf_has_multiple_threads (void)
{
int count = 0;
iterate_over_threads (inf_has_multiple_thread_cb, &count);
return (count > 1);
}
static void
checkpoint_command (char *args, int from_tty)
{
struct objfile *fork_objf;
struct gdbarch *gdbarch;
struct target_waitstatus last_target_waitstatus;
ptid_t last_target_ptid;
struct value *fork_fn = NULL, *ret;
struct fork_info *fp;
pid_t retpid;
struct cleanup *old_chain;
if (!target_has_execution)
error (_("The program is not being run."));
/* Ensure that the inferior is not multithreaded. */
update_thread_list ();
if (inf_has_multiple_threads ())
error (_("checkpoint: can't checkpoint multiple threads."));
/* Make the inferior fork, record its (and gdb's) state. */
if (lookup_minimal_symbol ("fork", NULL, NULL).minsym != NULL)
fork_fn = find_function_in_inferior ("fork", &fork_objf);
if (!fork_fn)
if (lookup_minimal_symbol ("_fork", NULL, NULL).minsym != NULL)
fork_fn = find_function_in_inferior ("fork", &fork_objf);
if (!fork_fn)
error (_("checkpoint: can't find fork function in inferior."));
gdbarch = get_objfile_arch (fork_objf);
ret = value_from_longest (builtin_type (gdbarch)->builtin_int, 0);
/* Tell linux-nat.c that we're checkpointing this inferior. */
old_chain = make_cleanup_restore_integer (&checkpointing_pid);
checkpointing_pid = ptid_get_pid (inferior_ptid);
ret = call_function_by_hand (fork_fn, 0, &ret);
do_cleanups (old_chain);
if (!ret) /* Probably can't happen. */
error (_("checkpoint: call_function_by_hand returned null."));
retpid = value_as_long (ret);
get_last_target_status (&last_target_ptid, &last_target_waitstatus);
fp = find_fork_pid (retpid);
if (from_tty)
{
int parent_pid;
printf_filtered (_("checkpoint %d: fork returned pid %ld.\n"),
fp != NULL ? fp->num : -1, (long) retpid);
if (info_verbose)
{
parent_pid = ptid_get_lwp (last_target_ptid);
if (parent_pid == 0)
parent_pid = ptid_get_pid (last_target_ptid);
printf_filtered (_(" gdb says parent = %ld.\n"),
(long) parent_pid);
}
}
if (!fp)
error (_("Failed to find new fork"));
fork_save_infrun_state (fp, 1);
fp->parent_ptid = last_target_ptid;
}
static void
linux_fork_context (struct fork_info *newfp, int from_tty)
{
/* Now we attempt to switch processes. */
struct fork_info *oldfp;
gdb_assert (newfp != NULL);
oldfp = find_fork_ptid (inferior_ptid);
gdb_assert (oldfp != NULL);
fork_save_infrun_state (oldfp, 1);
remove_breakpoints ();
fork_load_infrun_state (newfp);
insert_breakpoints ();
printf_filtered (_("Switching to %s\n"),
target_pid_to_str (inferior_ptid));
print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC, 1);
}
/* Switch inferior process (checkpoint) context, by checkpoint id. */
static void
restart_command (char *args, int from_tty)
{
struct fork_info *fp;
if (!args || !*args)
error (_("Requires argument (checkpoint id to restart)"));
if ((fp = find_fork_id (parse_and_eval_long (args))) == NULL)
error (_("Not found: checkpoint id %s"), args);
linux_fork_context (fp, from_tty);
}
void
_initialize_linux_fork (void)
{
init_fork_list ();
/* Checkpoint command: create a fork of the inferior process
and set it aside for later debugging. */
add_com ("checkpoint", class_obscure, checkpoint_command, _("\
Fork a duplicate process (experimental)."));
/* Restart command: restore the context of a specified checkpoint
process. */
add_com ("restart", class_obscure, restart_command, _("\
restart <n>: restore program context from a checkpoint.\n\
Argument 'n' is checkpoint ID, as displayed by 'info checkpoints'."));
/* Delete checkpoint command: kill the process and remove it from
the fork list. */
add_cmd ("checkpoint", class_obscure, delete_checkpoint_command, _("\
Delete a checkpoint (experimental)."),
&deletelist);
/* Detach checkpoint command: release the process to run independently,
and remove it from the fork list. */
add_cmd ("checkpoint", class_obscure, detach_checkpoint_command, _("\
Detach from a checkpoint (experimental)."),
&detachlist);
/* Info checkpoints command: list all forks/checkpoints
currently under gdb's control. */
add_info ("checkpoints", info_checkpoints_command,
_("IDs of currently known checkpoints."));
}
|