1 /* GNU/Linux native-dependent code common to multiple platforms.
3 Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
6 This file is part of GDB.
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.
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.
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/>. */
24 #include "gdb_string.h"
26 #include "gdb_assert.h"
27 #ifdef HAVE_TKILL_SYSCALL
29 #include <sys/syscall.h>
31 #include <sys/ptrace.h>
32 #include "linux-nat.h"
33 #include "linux-fork.h"
34 #include "gdbthread.h"
38 #include "inf-ptrace.h"
40 #include <sys/param.h> /* for MAXPATHLEN */
41 #include <sys/procfs.h> /* for elf_gregset etc. */
42 #include "elf-bfd.h" /* for elfcore_write_* */
43 #include "gregset.h" /* for gregset */
44 #include "gdbcore.h" /* for get_exec_file */
45 #include <ctype.h> /* for isdigit */
46 #include "gdbthread.h" /* for struct thread_info etc. */
47 #include "gdb_stat.h" /* for struct stat */
48 #include <fcntl.h> /* for O_RDONLY */
50 #include "event-loop.h"
51 #include "event-top.h"
53 #include <sys/types.h>
54 #include "gdb_dirent.h"
55 #include "xml-support.h"
58 #ifdef HAVE_PERSONALITY
59 # include <sys/personality.h>
60 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
61 # define ADDR_NO_RANDOMIZE 0x0040000
63 #endif /* HAVE_PERSONALITY */
65 /* This comment documents high-level logic of this file.
67 Waiting for events in sync mode
68 ===============================
70 When waiting for an event in a specific thread, we just use waitpid, passing
71 the specific pid, and not passing WNOHANG.
73 When waiting for an event in all threads, waitpid is not quite good. Prior to
74 version 2.4, Linux can either wait for event in main thread, or in secondary
75 threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might
76 miss an event. The solution is to use non-blocking waitpid, together with
77 sigsuspend. First, we use non-blocking waitpid to get an event in the main
78 process, if any. Second, we use non-blocking waitpid with the __WCLONED
79 flag to check for events in cloned processes. If nothing is found, we use
80 sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something
81 happened to a child process -- and SIGCHLD will be delivered both for events
82 in main debugged process and in cloned processes. As soon as we know there's
83 an event, we get back to calling nonblocking waitpid with and without __WCLONED.
85 Note that SIGCHLD should be blocked between waitpid and sigsuspend calls,
86 so that we don't miss a signal. If SIGCHLD arrives in between, when it's
87 blocked, the signal becomes pending and sigsuspend immediately
88 notices it and returns.
90 Waiting for events in async mode
91 ================================
93 In async mode, GDB should always be ready to handle both user input
94 and target events, so neither blocking waitpid nor sigsuspend are
95 viable options. Instead, we should asynchronously notify the GDB main
96 event loop whenever there's an unprocessed event from the target. We
97 detect asynchronous target events by handling SIGCHLD signals. To
98 notify the event loop about target events, the self-pipe trick is used
99 --- a pipe is registered as waitable event source in the event loop,
100 the event loop select/poll's on the read end of this pipe (as well on
101 other event sources, e.g., stdin), and the SIGCHLD handler writes a
102 byte to this pipe. This is more portable than relying on
103 pselect/ppoll, since on kernels that lack those syscalls, libc
104 emulates them with select/poll+sigprocmask, and that is racy
105 (a.k.a. plain broken).
107 Obviously, if we fail to notify the event loop if there's a target
108 event, it's bad. OTOH, if we notify the event loop when there's no
109 event from the target, linux_nat_wait will detect that there's no real
110 event to report, and return event of type TARGET_WAITKIND_IGNORE.
111 This is mostly harmless, but it will waste time and is better avoided.
113 The main design point is that every time GDB is outside linux-nat.c,
114 we have a SIGCHLD handler installed that is called when something
115 happens to the target and notifies the GDB event loop. Whenever GDB
116 core decides to handle the event, and calls into linux-nat.c, we
117 process things as in sync mode, except that the we never block in
120 While processing an event, we may end up momentarily blocked in
121 waitpid calls. Those waitpid calls, while blocking, are guarantied to
122 return quickly. E.g., in all-stop mode, before reporting to the core
123 that an LWP hit a breakpoint, all LWPs are stopped by sending them
124 SIGSTOP, and synchronously waiting for the SIGSTOP to be reported.
125 Note that this is different from blocking indefinitely waiting for the
126 next event --- here, we're already handling an event.
131 We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another
132 signal is not entirely significant; we just need for a signal to be delivered,
133 so that we can intercept it. SIGSTOP's advantage is that it can not be
134 blocked. A disadvantage is that it is not a real-time signal, so it can only
135 be queued once; we do not keep track of other sources of SIGSTOP.
137 Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't
138 use them, because they have special behavior when the signal is generated -
139 not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL
140 kills the entire thread group.
142 A delivered SIGSTOP would stop the entire thread group, not just the thread we
143 tkill'd. But we never let the SIGSTOP be delivered; we always intercept and
144 cancel it (by PTRACE_CONT without passing SIGSTOP).
146 We could use a real-time signal instead. This would solve those problems; we
147 could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB.
148 But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH
149 generates it, and there are races with trying to find a signal that is not
153 #define O_LARGEFILE 0
156 /* If the system headers did not provide the constants, hard-code the normal
158 #ifndef PTRACE_EVENT_FORK
160 #define PTRACE_SETOPTIONS 0x4200
161 #define PTRACE_GETEVENTMSG 0x4201
163 /* options set using PTRACE_SETOPTIONS */
164 #define PTRACE_O_TRACESYSGOOD 0x00000001
165 #define PTRACE_O_TRACEFORK 0x00000002
166 #define PTRACE_O_TRACEVFORK 0x00000004
167 #define PTRACE_O_TRACECLONE 0x00000008
168 #define PTRACE_O_TRACEEXEC 0x00000010
169 #define PTRACE_O_TRACEVFORKDONE 0x00000020
170 #define PTRACE_O_TRACEEXIT 0x00000040
172 /* Wait extended result codes for the above trace options. */
173 #define PTRACE_EVENT_FORK 1
174 #define PTRACE_EVENT_VFORK 2
175 #define PTRACE_EVENT_CLONE 3
176 #define PTRACE_EVENT_EXEC 4
177 #define PTRACE_EVENT_VFORK_DONE 5
178 #define PTRACE_EVENT_EXIT 6
180 #endif /* PTRACE_EVENT_FORK */
182 /* We can't always assume that this flag is available, but all systems
183 with the ptrace event handlers also have __WALL, so it's safe to use
186 #define __WALL 0x40000000 /* Wait for any child. */
189 #ifndef PTRACE_GETSIGINFO
190 # define PTRACE_GETSIGINFO 0x4202
191 # define PTRACE_SETSIGINFO 0x4203
194 /* The single-threaded native GNU/Linux target_ops. We save a pointer for
195 the use of the multi-threaded target. */
196 static struct target_ops
*linux_ops
;
197 static struct target_ops linux_ops_saved
;
199 /* The method to call, if any, when a new thread is attached. */
200 static void (*linux_nat_new_thread
) (ptid_t
);
202 /* The method to call, if any, when the siginfo object needs to be
203 converted between the layout returned by ptrace, and the layout in
204 the architecture of the inferior. */
205 static int (*linux_nat_siginfo_fixup
) (struct siginfo
*,
209 /* The saved to_xfer_partial method, inherited from inf-ptrace.c.
210 Called by our to_xfer_partial. */
211 static LONGEST (*super_xfer_partial
) (struct target_ops
*,
213 const char *, gdb_byte
*,
217 static int debug_linux_nat
;
219 show_debug_linux_nat (struct ui_file
*file
, int from_tty
,
220 struct cmd_list_element
*c
, const char *value
)
222 fprintf_filtered (file
, _("Debugging of GNU/Linux lwp module is %s.\n"),
226 static int debug_linux_nat_async
= 0;
228 show_debug_linux_nat_async (struct ui_file
*file
, int from_tty
,
229 struct cmd_list_element
*c
, const char *value
)
231 fprintf_filtered (file
, _("Debugging of GNU/Linux async lwp module is %s.\n"),
235 static int disable_randomization
= 1;
238 show_disable_randomization (struct ui_file
*file
, int from_tty
,
239 struct cmd_list_element
*c
, const char *value
)
241 #ifdef HAVE_PERSONALITY
242 fprintf_filtered (file
, _("\
243 Disabling randomization of debuggee's virtual address space is %s.\n"),
245 #else /* !HAVE_PERSONALITY */
247 Disabling randomization of debuggee's virtual address space is unsupported on\n\
248 this platform.\n"), file
);
249 #endif /* !HAVE_PERSONALITY */
253 set_disable_randomization (char *args
, int from_tty
, struct cmd_list_element
*c
)
255 #ifndef HAVE_PERSONALITY
257 Disabling randomization of debuggee's virtual address space is unsupported on\n\
259 #endif /* !HAVE_PERSONALITY */
262 static int linux_parent_pid
;
264 struct simple_pid_list
268 struct simple_pid_list
*next
;
270 struct simple_pid_list
*stopped_pids
;
272 /* This variable is a tri-state flag: -1 for unknown, 0 if PTRACE_O_TRACEFORK
273 can not be used, 1 if it can. */
275 static int linux_supports_tracefork_flag
= -1;
277 /* If we have PTRACE_O_TRACEFORK, this flag indicates whether we also have
278 PTRACE_O_TRACEVFORKDONE. */
280 static int linux_supports_tracevforkdone_flag
= -1;
282 /* Async mode support */
284 /* Zero if the async mode, although enabled, is masked, which means
285 linux_nat_wait should behave as if async mode was off. */
286 static int linux_nat_async_mask_value
= 1;
288 /* The read/write ends of the pipe registered as waitable file in the
290 static int linux_nat_event_pipe
[2] = { -1, -1 };
292 /* Flush the event pipe. */
295 async_file_flush (void)
302 ret
= read (linux_nat_event_pipe
[0], &buf
, 1);
304 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
307 /* Put something (anything, doesn't matter what, or how much) in event
308 pipe, so that the select/poll in the event-loop realizes we have
309 something to process. */
312 async_file_mark (void)
316 /* It doesn't really matter what the pipe contains, as long we end
317 up with something in it. Might as well flush the previous
323 ret
= write (linux_nat_event_pipe
[1], "+", 1);
325 while (ret
== -1 && errno
== EINTR
);
327 /* Ignore EAGAIN. If the pipe is full, the event loop will already
328 be awakened anyway. */
331 static void linux_nat_async (void (*callback
)
332 (enum inferior_event_type event_type
, void *context
),
334 static int linux_nat_async_mask (int mask
);
335 static int kill_lwp (int lwpid
, int signo
);
337 static int stop_callback (struct lwp_info
*lp
, void *data
);
339 static void block_child_signals (sigset_t
*prev_mask
);
340 static void restore_child_signals_mask (sigset_t
*prev_mask
);
342 /* Trivial list manipulation functions to keep track of a list of
343 new stopped processes. */
345 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
347 struct simple_pid_list
*new_pid
= xmalloc (sizeof (struct simple_pid_list
));
349 new_pid
->status
= status
;
350 new_pid
->next
= *listp
;
355 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *status
)
357 struct simple_pid_list
**p
;
359 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
360 if ((*p
)->pid
== pid
)
362 struct simple_pid_list
*next
= (*p
)->next
;
363 *status
= (*p
)->status
;
372 linux_record_stopped_pid (int pid
, int status
)
374 add_to_pid_list (&stopped_pids
, pid
, status
);
378 /* A helper function for linux_test_for_tracefork, called after fork (). */
381 linux_tracefork_child (void)
385 ptrace (PTRACE_TRACEME
, 0, 0, 0);
386 kill (getpid (), SIGSTOP
);
391 /* Wrapper function for waitpid which handles EINTR. */
394 my_waitpid (int pid
, int *status
, int flags
)
400 ret
= waitpid (pid
, status
, flags
);
402 while (ret
== -1 && errno
== EINTR
);
407 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events.
409 First, we try to enable fork tracing on ORIGINAL_PID. If this fails,
410 we know that the feature is not available. This may change the tracing
411 options for ORIGINAL_PID, but we'll be setting them shortly anyway.
413 However, if it succeeds, we don't know for sure that the feature is
414 available; old versions of PTRACE_SETOPTIONS ignored unknown options. We
415 create a child process, attach to it, use PTRACE_SETOPTIONS to enable
416 fork tracing, and let it fork. If the process exits, we assume that we
417 can't use TRACEFORK; if we get the fork notification, and we can extract
418 the new child's PID, then we assume that we can. */
421 linux_test_for_tracefork (int original_pid
)
423 int child_pid
, ret
, status
;
427 /* We don't want those ptrace calls to be interrupted. */
428 block_child_signals (&prev_mask
);
430 linux_supports_tracefork_flag
= 0;
431 linux_supports_tracevforkdone_flag
= 0;
433 ret
= ptrace (PTRACE_SETOPTIONS
, original_pid
, 0, PTRACE_O_TRACEFORK
);
436 restore_child_signals_mask (&prev_mask
);
442 perror_with_name (("fork"));
445 linux_tracefork_child ();
447 ret
= my_waitpid (child_pid
, &status
, 0);
449 perror_with_name (("waitpid"));
450 else if (ret
!= child_pid
)
451 error (_("linux_test_for_tracefork: waitpid: unexpected result %d."), ret
);
452 if (! WIFSTOPPED (status
))
453 error (_("linux_test_for_tracefork: waitpid: unexpected status %d."), status
);
455 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0, PTRACE_O_TRACEFORK
);
458 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
461 warning (_("linux_test_for_tracefork: failed to kill child"));
462 restore_child_signals_mask (&prev_mask
);
466 ret
= my_waitpid (child_pid
, &status
, 0);
467 if (ret
!= child_pid
)
468 warning (_("linux_test_for_tracefork: failed to wait for killed child"));
469 else if (!WIFSIGNALED (status
))
470 warning (_("linux_test_for_tracefork: unexpected wait status 0x%x from "
471 "killed child"), status
);
473 restore_child_signals_mask (&prev_mask
);
477 /* Check whether PTRACE_O_TRACEVFORKDONE is available. */
478 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
479 PTRACE_O_TRACEFORK
| PTRACE_O_TRACEVFORKDONE
);
480 linux_supports_tracevforkdone_flag
= (ret
== 0);
482 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
484 warning (_("linux_test_for_tracefork: failed to resume child"));
486 ret
= my_waitpid (child_pid
, &status
, 0);
488 if (ret
== child_pid
&& WIFSTOPPED (status
)
489 && status
>> 16 == PTRACE_EVENT_FORK
)
492 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
493 if (ret
== 0 && second_pid
!= 0)
497 linux_supports_tracefork_flag
= 1;
498 my_waitpid (second_pid
, &second_status
, 0);
499 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
501 warning (_("linux_test_for_tracefork: failed to kill second child"));
502 my_waitpid (second_pid
, &status
, 0);
506 warning (_("linux_test_for_tracefork: unexpected result from waitpid "
507 "(%d, status 0x%x)"), ret
, status
);
509 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
511 warning (_("linux_test_for_tracefork: failed to kill child"));
512 my_waitpid (child_pid
, &status
, 0);
514 restore_child_signals_mask (&prev_mask
);
517 /* Return non-zero iff we have tracefork functionality available.
518 This function also sets linux_supports_tracefork_flag. */
521 linux_supports_tracefork (int pid
)
523 if (linux_supports_tracefork_flag
== -1)
524 linux_test_for_tracefork (pid
);
525 return linux_supports_tracefork_flag
;
529 linux_supports_tracevforkdone (int pid
)
531 if (linux_supports_tracefork_flag
== -1)
532 linux_test_for_tracefork (pid
);
533 return linux_supports_tracevforkdone_flag
;
538 linux_enable_event_reporting (ptid_t ptid
)
540 int pid
= ptid_get_lwp (ptid
);
544 pid
= ptid_get_pid (ptid
);
546 if (! linux_supports_tracefork (pid
))
549 options
= PTRACE_O_TRACEFORK
| PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEEXEC
550 | PTRACE_O_TRACECLONE
;
551 if (linux_supports_tracevforkdone (pid
))
552 options
|= PTRACE_O_TRACEVFORKDONE
;
554 /* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to support
555 read-only process state. */
557 ptrace (PTRACE_SETOPTIONS
, pid
, 0, options
);
561 linux_child_post_attach (int pid
)
563 linux_enable_event_reporting (pid_to_ptid (pid
));
564 check_for_thread_db ();
568 linux_child_post_startup_inferior (ptid_t ptid
)
570 linux_enable_event_reporting (ptid
);
571 check_for_thread_db ();
575 linux_child_follow_fork (struct target_ops
*ops
, int follow_child
)
579 struct target_waitstatus last_status
;
581 int parent_pid
, child_pid
;
583 block_child_signals (&prev_mask
);
585 get_last_target_status (&last_ptid
, &last_status
);
586 has_vforked
= (last_status
.kind
== TARGET_WAITKIND_VFORKED
);
587 parent_pid
= ptid_get_lwp (last_ptid
);
589 parent_pid
= ptid_get_pid (last_ptid
);
590 child_pid
= PIDGET (last_status
.value
.related_pid
);
594 /* We're already attached to the parent, by default. */
596 /* Before detaching from the child, remove all breakpoints from
597 it. If we forked, then this has already been taken care of
598 by infrun.c. If we vforked however, any breakpoint inserted
599 in the parent is visible in the child, even those added while
600 stopped in a vfork catchpoint. This won't actually modify
601 the breakpoint list, but will physically remove the
602 breakpoints from the child. This will remove the breakpoints
603 from the parent also, but they'll be reinserted below. */
605 detach_breakpoints (child_pid
);
607 /* Detach new forked process? */
610 if (info_verbose
|| debug_linux_nat
)
612 target_terminal_ours ();
613 fprintf_filtered (gdb_stdlog
,
614 "Detaching after fork from child process %d.\n",
618 ptrace (PTRACE_DETACH
, child_pid
, 0, 0);
622 struct fork_info
*fp
;
623 struct inferior
*parent_inf
, *child_inf
;
625 /* Add process to GDB's tables. */
626 child_inf
= add_inferior (child_pid
);
628 parent_inf
= find_inferior_pid (GET_PID (last_ptid
));
629 child_inf
->attach_flag
= parent_inf
->attach_flag
;
630 copy_terminal_info (child_inf
, parent_inf
);
632 /* Retain child fork in ptrace (stopped) state. */
633 fp
= find_fork_pid (child_pid
);
635 fp
= add_fork (child_pid
);
636 fork_save_infrun_state (fp
, 0);
641 gdb_assert (linux_supports_tracefork_flag
>= 0);
642 if (linux_supports_tracevforkdone (0))
646 ptrace (PTRACE_CONT
, parent_pid
, 0, 0);
647 my_waitpid (parent_pid
, &status
, __WALL
);
648 if ((status
>> 16) != PTRACE_EVENT_VFORK_DONE
)
649 warning (_("Unexpected waitpid result %06x when waiting for "
650 "vfork-done"), status
);
654 /* We can't insert breakpoints until the child has
655 finished with the shared memory region. We need to
656 wait until that happens. Ideal would be to just
658 - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0);
659 - waitpid (parent_pid, &status, __WALL);
660 However, most architectures can't handle a syscall
661 being traced on the way out if it wasn't traced on
664 We might also think to loop, continuing the child
665 until it exits or gets a SIGTRAP. One problem is
666 that the child might call ptrace with PTRACE_TRACEME.
668 There's no simple and reliable way to figure out when
669 the vforked child will be done with its copy of the
670 shared memory. We could step it out of the syscall,
671 two instructions, let it go, and then single-step the
672 parent once. When we have hardware single-step, this
673 would work; with software single-step it could still
674 be made to work but we'd have to be able to insert
675 single-step breakpoints in the child, and we'd have
676 to insert -just- the single-step breakpoint in the
677 parent. Very awkward.
679 In the end, the best we can do is to make sure it
680 runs for a little while. Hopefully it will be out of
681 range of any breakpoints we reinsert. Usually this
682 is only the single-step breakpoint at vfork's return
688 /* Since we vforked, breakpoints were removed in the parent
689 too. Put them back. */
690 reattach_breakpoints (parent_pid
);
695 struct thread_info
*last_tp
= find_thread_pid (last_ptid
);
696 struct thread_info
*tp
;
697 char child_pid_spelling
[40];
698 struct inferior
*parent_inf
, *child_inf
;
700 /* Copy user stepping state to the new inferior thread. */
701 struct breakpoint
*step_resume_breakpoint
= last_tp
->step_resume_breakpoint
;
702 CORE_ADDR step_range_start
= last_tp
->step_range_start
;
703 CORE_ADDR step_range_end
= last_tp
->step_range_end
;
704 struct frame_id step_frame_id
= last_tp
->step_frame_id
;
706 /* Otherwise, deleting the parent would get rid of this
708 last_tp
->step_resume_breakpoint
= NULL
;
710 /* Before detaching from the parent, remove all breakpoints from it. */
711 remove_breakpoints ();
713 if (info_verbose
|| debug_linux_nat
)
715 target_terminal_ours ();
716 fprintf_filtered (gdb_stdlog
,
717 "Attaching after fork to child process %d.\n",
721 /* Add the new inferior first, so that the target_detach below
722 doesn't unpush the target. */
724 child_inf
= add_inferior (child_pid
);
726 parent_inf
= find_inferior_pid (GET_PID (last_ptid
));
727 child_inf
->attach_flag
= parent_inf
->attach_flag
;
728 copy_terminal_info (child_inf
, parent_inf
);
730 /* If we're vforking, we may want to hold on to the parent until
731 the child exits or execs. At exec time we can remove the old
732 breakpoints from the parent and detach it; at exit time we
733 could do the same (or even, sneakily, resume debugging it - the
734 child's exec has failed, or something similar).
736 This doesn't clean up "properly", because we can't call
737 target_detach, but that's OK; if the current target is "child",
738 then it doesn't need any further cleanups, and lin_lwp will
739 generally not encounter vfork (vfork is defined to fork
742 The holding part is very easy if we have VFORKDONE events;
743 but keeping track of both processes is beyond GDB at the
744 moment. So we don't expose the parent to the rest of GDB.
745 Instead we quietly hold onto it until such time as we can
750 linux_parent_pid
= parent_pid
;
751 detach_inferior (parent_pid
);
753 else if (!detach_fork
)
755 struct fork_info
*fp
;
756 /* Retain parent fork in ptrace (stopped) state. */
757 fp
= find_fork_pid (parent_pid
);
759 fp
= add_fork (parent_pid
);
760 fork_save_infrun_state (fp
, 0);
762 /* Also add an entry for the child fork. */
763 fp
= find_fork_pid (child_pid
);
765 fp
= add_fork (child_pid
);
766 fork_save_infrun_state (fp
, 0);
769 target_detach (NULL
, 0);
771 inferior_ptid
= ptid_build (child_pid
, child_pid
, 0);
773 linux_nat_switch_fork (inferior_ptid
);
774 check_for_thread_db ();
776 tp
= inferior_thread ();
777 tp
->step_resume_breakpoint
= step_resume_breakpoint
;
778 tp
->step_range_start
= step_range_start
;
779 tp
->step_range_end
= step_range_end
;
780 tp
->step_frame_id
= step_frame_id
;
782 /* Reset breakpoints in the child as appropriate. */
783 follow_inferior_reset_breakpoints ();
786 restore_child_signals_mask (&prev_mask
);
792 linux_child_insert_fork_catchpoint (int pid
)
794 if (! linux_supports_tracefork (pid
))
795 error (_("Your system does not support fork catchpoints."));
799 linux_child_insert_vfork_catchpoint (int pid
)
801 if (!linux_supports_tracefork (pid
))
802 error (_("Your system does not support vfork catchpoints."));
806 linux_child_insert_exec_catchpoint (int pid
)
808 if (!linux_supports_tracefork (pid
))
809 error (_("Your system does not support exec catchpoints."));
812 /* On GNU/Linux there are no real LWP's. The closest thing to LWP's
813 are processes sharing the same VM space. A multi-threaded process
814 is basically a group of such processes. However, such a grouping
815 is almost entirely a user-space issue; the kernel doesn't enforce
816 such a grouping at all (this might change in the future). In
817 general, we'll rely on the threads library (i.e. the GNU/Linux
818 Threads library) to provide such a grouping.
820 It is perfectly well possible to write a multi-threaded application
821 without the assistance of a threads library, by using the clone
822 system call directly. This module should be able to give some
823 rudimentary support for debugging such applications if developers
824 specify the CLONE_PTRACE flag in the clone system call, and are
825 using the Linux kernel 2.4 or above.
827 Note that there are some peculiarities in GNU/Linux that affect
830 - In general one should specify the __WCLONE flag to waitpid in
831 order to make it report events for any of the cloned processes
832 (and leave it out for the initial process). However, if a cloned
833 process has exited the exit status is only reported if the
834 __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but
835 we cannot use it since GDB must work on older systems too.
837 - When a traced, cloned process exits and is waited for by the
838 debugger, the kernel reassigns it to the original parent and
839 keeps it around as a "zombie". Somehow, the GNU/Linux Threads
840 library doesn't notice this, which leads to the "zombie problem":
841 When debugged a multi-threaded process that spawns a lot of
842 threads will run out of processes, even if the threads exit,
843 because the "zombies" stay around. */
845 /* List of known LWPs. */
846 struct lwp_info
*lwp_list
;
849 /* Original signal mask. */
850 static sigset_t normal_mask
;
852 /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in
853 _initialize_linux_nat. */
854 static sigset_t suspend_mask
;
856 /* Signals to block to make that sigsuspend work. */
857 static sigset_t blocked_mask
;
859 /* SIGCHLD action. */
860 struct sigaction sigchld_action
;
862 /* Block child signals (SIGCHLD and linux threads signals), and store
863 the previous mask in PREV_MASK. */
866 block_child_signals (sigset_t
*prev_mask
)
868 /* Make sure SIGCHLD is blocked. */
869 if (!sigismember (&blocked_mask
, SIGCHLD
))
870 sigaddset (&blocked_mask
, SIGCHLD
);
872 sigprocmask (SIG_BLOCK
, &blocked_mask
, prev_mask
);
875 /* Restore child signals mask, previously returned by
876 block_child_signals. */
879 restore_child_signals_mask (sigset_t
*prev_mask
)
881 sigprocmask (SIG_SETMASK
, prev_mask
, NULL
);
885 /* Prototypes for local functions. */
886 static int stop_wait_callback (struct lwp_info
*lp
, void *data
);
887 static int linux_thread_alive (ptid_t ptid
);
888 static char *linux_child_pid_to_exec_file (int pid
);
889 static int cancel_breakpoint (struct lwp_info
*lp
);
892 /* Convert wait status STATUS to a string. Used for printing debug
896 status_to_str (int status
)
900 if (WIFSTOPPED (status
))
901 snprintf (buf
, sizeof (buf
), "%s (stopped)",
902 strsignal (WSTOPSIG (status
)));
903 else if (WIFSIGNALED (status
))
904 snprintf (buf
, sizeof (buf
), "%s (terminated)",
905 strsignal (WSTOPSIG (status
)));
907 snprintf (buf
, sizeof (buf
), "%d (exited)", WEXITSTATUS (status
));
912 /* Initialize the list of LWPs. Note that this module, contrary to
913 what GDB's generic threads layer does for its thread list,
914 re-initializes the LWP lists whenever we mourn or detach (which
915 doesn't involve mourning) the inferior. */
920 struct lwp_info
*lp
, *lpnext
;
922 for (lp
= lwp_list
; lp
; lp
= lpnext
)
931 /* Remove all LWPs belong to PID from the lwp list. */
934 purge_lwp_list (int pid
)
936 struct lwp_info
*lp
, *lpprev
, *lpnext
;
940 for (lp
= lwp_list
; lp
; lp
= lpnext
)
944 if (ptid_get_pid (lp
->ptid
) == pid
)
949 lpprev
->next
= lp
->next
;
958 /* Return the number of known LWPs in the tgid given by PID. */
966 for (lp
= lwp_list
; lp
; lp
= lp
->next
)
967 if (ptid_get_pid (lp
->ptid
) == pid
)
973 /* Add the LWP specified by PID to the list. Return a pointer to the
974 structure describing the new LWP. The LWP should already be stopped
975 (with an exception for the very first LWP). */
977 static struct lwp_info
*
978 add_lwp (ptid_t ptid
)
982 gdb_assert (is_lwp (ptid
));
984 lp
= (struct lwp_info
*) xmalloc (sizeof (struct lwp_info
));
986 memset (lp
, 0, sizeof (struct lwp_info
));
988 lp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
995 if (num_lwps (GET_PID (ptid
)) > 1 && linux_nat_new_thread
!= NULL
)
996 linux_nat_new_thread (ptid
);
1001 /* Remove the LWP specified by PID from the list. */
1004 delete_lwp (ptid_t ptid
)
1006 struct lwp_info
*lp
, *lpprev
;
1010 for (lp
= lwp_list
; lp
; lpprev
= lp
, lp
= lp
->next
)
1011 if (ptid_equal (lp
->ptid
, ptid
))
1018 lpprev
->next
= lp
->next
;
1020 lwp_list
= lp
->next
;
1025 /* Return a pointer to the structure describing the LWP corresponding
1026 to PID. If no corresponding LWP could be found, return NULL. */
1028 static struct lwp_info
*
1029 find_lwp_pid (ptid_t ptid
)
1031 struct lwp_info
*lp
;
1035 lwp
= GET_LWP (ptid
);
1037 lwp
= GET_PID (ptid
);
1039 for (lp
= lwp_list
; lp
; lp
= lp
->next
)
1040 if (lwp
== GET_LWP (lp
->ptid
))
1046 /* Returns true if PTID matches filter FILTER. FILTER can be the wild
1047 card MINUS_ONE_PTID (all ptid match it); can be a ptid representing
1048 a process (ptid_is_pid returns true), in which case, all lwps of
1049 that give process match, lwps of other process do not; or, it can
1050 represent a specific thread, in which case, only that thread will
1051 match true. PTID must represent an LWP, it can never be a wild
1055 ptid_match (ptid_t ptid
, ptid_t filter
)
1057 /* Since both parameters have the same type, prevent easy mistakes
1059 gdb_assert (!ptid_equal (ptid
, minus_one_ptid
)
1060 && !ptid_equal (ptid
, null_ptid
));
1062 if (ptid_equal (filter
, minus_one_ptid
))
1064 if (ptid_is_pid (filter
)
1065 && ptid_get_pid (ptid
) == ptid_get_pid (filter
))
1067 else if (ptid_equal (ptid
, filter
))
1073 /* Call CALLBACK with its second argument set to DATA for every LWP in
1074 the list. If CALLBACK returns 1 for a particular LWP, return a
1075 pointer to the structure describing that LWP immediately.
1076 Otherwise return NULL. */
1079 iterate_over_lwps (ptid_t filter
,
1080 int (*callback
) (struct lwp_info
*, void *),
1083 struct lwp_info
*lp
, *lpnext
;
1085 for (lp
= lwp_list
; lp
; lp
= lpnext
)
1089 if (ptid_match (lp
->ptid
, filter
))
1091 if ((*callback
) (lp
, data
))
1099 /* Update our internal state when changing from one fork (checkpoint,
1100 et cetera) to another indicated by NEW_PTID. We can only switch
1101 single-threaded applications, so we only create one new LWP, and
1102 the previous list is discarded. */
1105 linux_nat_switch_fork (ptid_t new_ptid
)
1107 struct lwp_info
*lp
;
1110 lp
= add_lwp (new_ptid
);
1113 init_thread_list ();
1114 add_thread_silent (new_ptid
);
1117 /* Handle the exit of a single thread LP. */
1120 exit_lwp (struct lwp_info
*lp
)
1122 struct thread_info
*th
= find_thread_pid (lp
->ptid
);
1126 if (print_thread_events
)
1127 printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp
->ptid
));
1129 delete_thread (lp
->ptid
);
1132 delete_lwp (lp
->ptid
);
1135 /* Return an lwp's tgid, found in `/proc/PID/status'. */
1138 linux_proc_get_tgid (int lwpid
)
1144 snprintf (buf
, sizeof (buf
), "/proc/%d/status", (int) lwpid
);
1145 status_file
= fopen (buf
, "r");
1146 if (status_file
!= NULL
)
1148 while (fgets (buf
, sizeof (buf
), status_file
))
1150 if (strncmp (buf
, "Tgid:", 5) == 0)
1152 tgid
= strtoul (buf
+ strlen ("Tgid:"), NULL
, 10);
1157 fclose (status_file
);
1163 /* Detect `T (stopped)' in `/proc/PID/status'.
1164 Other states including `T (tracing stop)' are reported as false. */
1167 pid_is_stopped (pid_t pid
)
1173 snprintf (buf
, sizeof (buf
), "/proc/%d/status", (int) pid
);
1174 status_file
= fopen (buf
, "r");
1175 if (status_file
!= NULL
)
1179 while (fgets (buf
, sizeof (buf
), status_file
))
1181 if (strncmp (buf
, "State:", 6) == 0)
1187 if (have_state
&& strstr (buf
, "T (stopped)") != NULL
)
1189 fclose (status_file
);
1194 /* Wait for the LWP specified by LP, which we have just attached to.
1195 Returns a wait status for that LWP, to cache. */
1198 linux_nat_post_attach_wait (ptid_t ptid
, int first
, int *cloned
,
1201 pid_t new_pid
, pid
= GET_LWP (ptid
);
1204 if (pid_is_stopped (pid
))
1206 if (debug_linux_nat
)
1207 fprintf_unfiltered (gdb_stdlog
,
1208 "LNPAW: Attaching to a stopped process\n");
1210 /* The process is definitely stopped. It is in a job control
1211 stop, unless the kernel predates the TASK_STOPPED /
1212 TASK_TRACED distinction, in which case it might be in a
1213 ptrace stop. Make sure it is in a ptrace stop; from there we
1214 can kill it, signal it, et cetera.
1216 First make sure there is a pending SIGSTOP. Since we are
1217 already attached, the process can not transition from stopped
1218 to running without a PTRACE_CONT; so we know this signal will
1219 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1220 probably already in the queue (unless this kernel is old
1221 enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP
1222 is not an RT signal, it can only be queued once. */
1223 kill_lwp (pid
, SIGSTOP
);
1225 /* Finally, resume the stopped process. This will deliver the SIGSTOP
1226 (or a higher priority signal, just like normal PTRACE_ATTACH). */
1227 ptrace (PTRACE_CONT
, pid
, 0, 0);
1230 /* Make sure the initial process is stopped. The user-level threads
1231 layer might want to poke around in the inferior, and that won't
1232 work if things haven't stabilized yet. */
1233 new_pid
= my_waitpid (pid
, &status
, 0);
1234 if (new_pid
== -1 && errno
== ECHILD
)
1237 warning (_("%s is a cloned process"), target_pid_to_str (ptid
));
1239 /* Try again with __WCLONE to check cloned processes. */
1240 new_pid
= my_waitpid (pid
, &status
, __WCLONE
);
1244 gdb_assert (pid
== new_pid
&& WIFSTOPPED (status
));
1246 if (WSTOPSIG (status
) != SIGSTOP
)
1249 if (debug_linux_nat
)
1250 fprintf_unfiltered (gdb_stdlog
,
1251 "LNPAW: Received %s after attaching\n",
1252 status_to_str (status
));
1258 /* Attach to the LWP specified by PID. Return 0 if successful or -1
1259 if the new LWP could not be attached. */
1262 lin_lwp_attach_lwp (ptid_t ptid
)
1264 struct lwp_info
*lp
;
1267 gdb_assert (is_lwp (ptid
));
1269 block_child_signals (&prev_mask
);
1271 lp
= find_lwp_pid (ptid
);
1273 /* We assume that we're already attached to any LWP that has an id
1274 equal to the overall process id, and to any LWP that is already
1275 in our list of LWPs. If we're not seeing exit events from threads
1276 and we've had PID wraparound since we last tried to stop all threads,
1277 this assumption might be wrong; fortunately, this is very unlikely
1279 if (GET_LWP (ptid
) != GET_PID (ptid
) && lp
== NULL
)
1281 int status
, cloned
= 0, signalled
= 0;
1283 if (ptrace (PTRACE_ATTACH
, GET_LWP (ptid
), 0, 0) < 0)
1285 /* If we fail to attach to the thread, issue a warning,
1286 but continue. One way this can happen is if thread
1287 creation is interrupted; as of Linux kernel 2.6.19, a
1288 bug may place threads in the thread list and then fail
1290 warning (_("Can't attach %s: %s"), target_pid_to_str (ptid
),
1291 safe_strerror (errno
));
1292 restore_child_signals_mask (&prev_mask
);
1296 if (debug_linux_nat
)
1297 fprintf_unfiltered (gdb_stdlog
,
1298 "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n",
1299 target_pid_to_str (ptid
));
1301 status
= linux_nat_post_attach_wait (ptid
, 0, &cloned
, &signalled
);
1302 lp
= add_lwp (ptid
);
1304 lp
->cloned
= cloned
;
1305 lp
->signalled
= signalled
;
1306 if (WSTOPSIG (status
) != SIGSTOP
)
1309 lp
->status
= status
;
1312 target_post_attach (GET_LWP (lp
->ptid
));
1314 if (debug_linux_nat
)
1316 fprintf_unfiltered (gdb_stdlog
,
1317 "LLAL: waitpid %s received %s\n",
1318 target_pid_to_str (ptid
),
1319 status_to_str (status
));
1324 /* We assume that the LWP representing the original process is
1325 already stopped. Mark it as stopped in the data structure
1326 that the GNU/linux ptrace layer uses to keep track of
1327 threads. Note that this won't have already been done since
1328 the main thread will have, we assume, been stopped by an
1329 attach from a different layer. */
1331 lp
= add_lwp (ptid
);
1335 restore_child_signals_mask (&prev_mask
);
1340 linux_nat_create_inferior (struct target_ops
*ops
,
1341 char *exec_file
, char *allargs
, char **env
,
1344 int saved_async
= 0;
1345 #ifdef HAVE_PERSONALITY
1346 int personality_orig
= 0, personality_set
= 0;
1347 #endif /* HAVE_PERSONALITY */
1349 /* The fork_child mechanism is synchronous and calls target_wait, so
1350 we have to mask the async mode. */
1352 if (target_can_async_p ())
1353 /* Mask async mode. Creating a child requires a loop calling
1354 wait_for_inferior currently. */
1355 saved_async
= linux_nat_async_mask (0);
1357 #ifdef HAVE_PERSONALITY
1358 if (disable_randomization
)
1361 personality_orig
= personality (0xffffffff);
1362 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
1364 personality_set
= 1;
1365 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
1367 if (errno
!= 0 || (personality_set
1368 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
1369 warning (_("Error disabling address space randomization: %s"),
1370 safe_strerror (errno
));
1372 #endif /* HAVE_PERSONALITY */
1374 linux_ops
->to_create_inferior (ops
, exec_file
, allargs
, env
, from_tty
);
1376 #ifdef HAVE_PERSONALITY
1377 if (personality_set
)
1380 personality (personality_orig
);
1382 warning (_("Error restoring address space randomization: %s"),
1383 safe_strerror (errno
));
1385 #endif /* HAVE_PERSONALITY */
1388 linux_nat_async_mask (saved_async
);
1392 linux_nat_attach (struct target_ops
*ops
, char *args
, int from_tty
)
1394 struct lwp_info
*lp
;
1398 linux_ops
->to_attach (ops
, args
, from_tty
);
1400 /* The ptrace base target adds the main thread with (pid,0,0)
1401 format. Decorate it with lwp info. */
1402 ptid
= BUILD_LWP (GET_PID (inferior_ptid
), GET_PID (inferior_ptid
));
1403 thread_change_ptid (inferior_ptid
, ptid
);
1405 /* Add the initial process as the first LWP to the list. */
1406 lp
= add_lwp (ptid
);
1408 status
= linux_nat_post_attach_wait (lp
->ptid
, 1, &lp
->cloned
,
1412 /* Save the wait status to report later. */
1414 if (debug_linux_nat
)
1415 fprintf_unfiltered (gdb_stdlog
,
1416 "LNA: waitpid %ld, saving status %s\n",
1417 (long) GET_PID (lp
->ptid
), status_to_str (status
));
1419 lp
->status
= status
;
1421 if (target_can_async_p ())
1422 target_async (inferior_event_handler
, 0);
1425 /* Get pending status of LP. */
1427 get_pending_status (struct lwp_info
*lp
, int *status
)
1429 struct target_waitstatus last
;
1432 get_last_target_status (&last_ptid
, &last
);
1434 /* If this lwp is the ptid that GDB is processing an event from, the
1435 signal will be in stop_signal. Otherwise, we may cache pending
1436 events in lp->status while trying to stop all threads (see
1437 stop_wait_callback). */
1443 enum target_signal signo
= TARGET_SIGNAL_0
;
1445 if (is_executing (lp
->ptid
))
1447 /* If the core thought this lwp was executing --- e.g., the
1448 executing property hasn't been updated yet, but the
1449 thread has been stopped with a stop_callback /
1450 stop_wait_callback sequence (see linux_nat_detach for
1451 example) --- we can only have pending events in the local
1453 signo
= target_signal_from_host (WSTOPSIG (lp
->status
));
1457 /* If the core knows the thread is not executing, then we
1458 have the last signal recorded in
1459 thread_info->stop_signal. */
1461 struct thread_info
*tp
= find_thread_pid (lp
->ptid
);
1462 signo
= tp
->stop_signal
;
1465 if (signo
!= TARGET_SIGNAL_0
1466 && !signal_pass_state (signo
))
1468 if (debug_linux_nat
)
1469 fprintf_unfiltered (gdb_stdlog
, "\
1470 GPT: lwp %s had signal %s, but it is in no pass state\n",
1471 target_pid_to_str (lp
->ptid
),
1472 target_signal_to_string (signo
));
1476 if (signo
!= TARGET_SIGNAL_0
)
1477 *status
= W_STOPCODE (target_signal_to_host (signo
));
1479 if (debug_linux_nat
)
1480 fprintf_unfiltered (gdb_stdlog
,
1481 "GPT: lwp %s as pending signal %s\n",
1482 target_pid_to_str (lp
->ptid
),
1483 target_signal_to_string (signo
));
1488 if (GET_LWP (lp
->ptid
) == GET_LWP (last_ptid
))
1490 struct thread_info
*tp
= find_thread_pid (lp
->ptid
);
1491 if (tp
->stop_signal
!= TARGET_SIGNAL_0
1492 && signal_pass_state (tp
->stop_signal
))
1493 *status
= W_STOPCODE (target_signal_to_host (tp
->stop_signal
));
1496 *status
= lp
->status
;
1503 detach_callback (struct lwp_info
*lp
, void *data
)
1505 gdb_assert (lp
->status
== 0 || WIFSTOPPED (lp
->status
));
1507 if (debug_linux_nat
&& lp
->status
)
1508 fprintf_unfiltered (gdb_stdlog
, "DC: Pending %s for %s on detach.\n",
1509 strsignal (WSTOPSIG (lp
->status
)),
1510 target_pid_to_str (lp
->ptid
));
1512 /* If there is a pending SIGSTOP, get rid of it. */
1515 if (debug_linux_nat
)
1516 fprintf_unfiltered (gdb_stdlog
,
1517 "DC: Sending SIGCONT to %s\n",
1518 target_pid_to_str (lp
->ptid
));
1520 kill_lwp (GET_LWP (lp
->ptid
), SIGCONT
);
1524 /* We don't actually detach from the LWP that has an id equal to the
1525 overall process id just yet. */
1526 if (GET_LWP (lp
->ptid
) != GET_PID (lp
->ptid
))
1530 /* Pass on any pending signal for this LWP. */
1531 get_pending_status (lp
, &status
);
1534 if (ptrace (PTRACE_DETACH
, GET_LWP (lp
->ptid
), 0,
1535 WSTOPSIG (status
)) < 0)
1536 error (_("Can't detach %s: %s"), target_pid_to_str (lp
->ptid
),
1537 safe_strerror (errno
));
1539 if (debug_linux_nat
)
1540 fprintf_unfiltered (gdb_stdlog
,
1541 "PTRACE_DETACH (%s, %s, 0) (OK)\n",
1542 target_pid_to_str (lp
->ptid
),
1543 strsignal (WSTOPSIG (status
)));
1545 delete_lwp (lp
->ptid
);
1552 linux_nat_detach (struct target_ops
*ops
, char *args
, int from_tty
)
1556 enum target_signal sig
;
1557 struct lwp_info
*main_lwp
;
1559 pid
= GET_PID (inferior_ptid
);
1561 if (target_can_async_p ())
1562 linux_nat_async (NULL
, 0);
1564 /* Stop all threads before detaching. ptrace requires that the
1565 thread is stopped to sucessfully detach. */
1566 iterate_over_lwps (pid_to_ptid (pid
), stop_callback
, NULL
);
1567 /* ... and wait until all of them have reported back that
1568 they're no longer running. */
1569 iterate_over_lwps (pid_to_ptid (pid
), stop_wait_callback
, NULL
);
1571 iterate_over_lwps (pid_to_ptid (pid
), detach_callback
, NULL
);
1573 /* Only the initial process should be left right now. */
1574 gdb_assert (num_lwps (GET_PID (inferior_ptid
)) == 1);
1576 main_lwp
= find_lwp_pid (pid_to_ptid (pid
));
1578 /* Pass on any pending signal for the last LWP. */
1579 if ((args
== NULL
|| *args
== '\0')
1580 && get_pending_status (main_lwp
, &status
) != -1
1581 && WIFSTOPPED (status
))
1583 /* Put the signal number in ARGS so that inf_ptrace_detach will
1584 pass it along with PTRACE_DETACH. */
1586 sprintf (args
, "%d", (int) WSTOPSIG (status
));
1587 fprintf_unfiltered (gdb_stdlog
,
1588 "LND: Sending signal %s to %s\n",
1590 target_pid_to_str (main_lwp
->ptid
));
1593 delete_lwp (main_lwp
->ptid
);
1595 if (forks_exist_p ())
1597 /* Multi-fork case. The current inferior_ptid is being detached
1598 from, but there are other viable forks to debug. Detach from
1599 the current fork, and context-switch to the first
1601 linux_fork_detach (args
, from_tty
);
1603 if (non_stop
&& target_can_async_p ())
1604 target_async (inferior_event_handler
, 0);
1607 linux_ops
->to_detach (ops
, args
, from_tty
);
1613 resume_callback (struct lwp_info
*lp
, void *data
)
1615 if (lp
->stopped
&& lp
->status
== 0)
1617 if (debug_linux_nat
)
1618 fprintf_unfiltered (gdb_stdlog
,
1619 "RC: PTRACE_CONT %s, 0, 0 (resuming sibling)\n",
1620 target_pid_to_str (lp
->ptid
));
1622 linux_ops
->to_resume (linux_ops
,
1623 pid_to_ptid (GET_LWP (lp
->ptid
)),
1624 0, TARGET_SIGNAL_0
);
1625 if (debug_linux_nat
)
1626 fprintf_unfiltered (gdb_stdlog
,
1627 "RC: PTRACE_CONT %s, 0, 0 (resume sibling)\n",
1628 target_pid_to_str (lp
->ptid
));
1631 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
1633 else if (lp
->stopped
&& debug_linux_nat
)
1634 fprintf_unfiltered (gdb_stdlog
, "RC: Not resuming sibling %s (has pending)\n",
1635 target_pid_to_str (lp
->ptid
));
1636 else if (debug_linux_nat
)
1637 fprintf_unfiltered (gdb_stdlog
, "RC: Not resuming sibling %s (not stopped)\n",
1638 target_pid_to_str (lp
->ptid
));
1644 resume_clear_callback (struct lwp_info
*lp
, void *data
)
1651 resume_set_callback (struct lwp_info
*lp
, void *data
)
1658 linux_nat_resume (struct target_ops
*ops
,
1659 ptid_t ptid
, int step
, enum target_signal signo
)
1662 struct lwp_info
*lp
;
1665 if (debug_linux_nat
)
1666 fprintf_unfiltered (gdb_stdlog
,
1667 "LLR: Preparing to %s %s, %s, inferior_ptid %s\n",
1668 step
? "step" : "resume",
1669 target_pid_to_str (ptid
),
1670 signo
? strsignal (signo
) : "0",
1671 target_pid_to_str (inferior_ptid
));
1673 block_child_signals (&prev_mask
);
1675 /* A specific PTID means `step only this process id'. */
1676 resume_many
= (ptid_equal (minus_one_ptid
, ptid
)
1677 || ptid_is_pid (ptid
));
1681 /* Mark the lwps we're resuming as resumed. */
1682 iterate_over_lwps (minus_one_ptid
, resume_clear_callback
, NULL
);
1683 iterate_over_lwps (ptid
, resume_set_callback
, NULL
);
1686 iterate_over_lwps (minus_one_ptid
, resume_set_callback
, NULL
);
1688 /* See if it's the current inferior that should be handled
1691 lp
= find_lwp_pid (inferior_ptid
);
1693 lp
= find_lwp_pid (ptid
);
1694 gdb_assert (lp
!= NULL
);
1696 /* Remember if we're stepping. */
1699 /* If we have a pending wait status for this thread, there is no
1700 point in resuming the process. But first make sure that
1701 linux_nat_wait won't preemptively handle the event - we
1702 should never take this short-circuit if we are going to
1703 leave LP running, since we have skipped resuming all the
1704 other threads. This bit of code needs to be synchronized
1705 with linux_nat_wait. */
1707 if (lp
->status
&& WIFSTOPPED (lp
->status
))
1710 struct inferior
*inf
;
1712 inf
= find_inferior_pid (ptid_get_pid (lp
->ptid
));
1714 saved_signo
= target_signal_from_host (WSTOPSIG (lp
->status
));
1716 /* Defer to common code if we're gaining control of the
1718 if (inf
->stop_soon
== NO_STOP_QUIETLY
1719 && signal_stop_state (saved_signo
) == 0
1720 && signal_print_state (saved_signo
) == 0
1721 && signal_pass_state (saved_signo
) == 1)
1723 if (debug_linux_nat
)
1724 fprintf_unfiltered (gdb_stdlog
,
1725 "LLR: Not short circuiting for ignored "
1726 "status 0x%x\n", lp
->status
);
1728 /* FIXME: What should we do if we are supposed to continue
1729 this thread with a signal? */
1730 gdb_assert (signo
== TARGET_SIGNAL_0
);
1731 signo
= saved_signo
;
1738 /* FIXME: What should we do if we are supposed to continue
1739 this thread with a signal? */
1740 gdb_assert (signo
== TARGET_SIGNAL_0
);
1742 if (debug_linux_nat
)
1743 fprintf_unfiltered (gdb_stdlog
,
1744 "LLR: Short circuiting for status 0x%x\n",
1747 restore_child_signals_mask (&prev_mask
);
1748 if (target_can_async_p ())
1750 target_async (inferior_event_handler
, 0);
1751 /* Tell the event loop we have something to process. */
1757 /* Mark LWP as not stopped to prevent it from being continued by
1762 iterate_over_lwps (ptid
, resume_callback
, NULL
);
1764 /* Convert to something the lower layer understands. */
1765 ptid
= pid_to_ptid (GET_LWP (lp
->ptid
));
1767 linux_ops
->to_resume (linux_ops
, ptid
, step
, signo
);
1768 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
1770 if (debug_linux_nat
)
1771 fprintf_unfiltered (gdb_stdlog
,
1772 "LLR: %s %s, %s (resume event thread)\n",
1773 step
? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
1774 target_pid_to_str (ptid
),
1775 signo
? strsignal (signo
) : "0");
1777 restore_child_signals_mask (&prev_mask
);
1778 if (target_can_async_p ())
1779 target_async (inferior_event_handler
, 0);
1782 /* Issue kill to specified lwp. */
1784 static int tkill_failed
;
1787 kill_lwp (int lwpid
, int signo
)
1791 /* Use tkill, if possible, in case we are using nptl threads. If tkill
1792 fails, then we are not using nptl threads and we should be using kill. */
1794 #ifdef HAVE_TKILL_SYSCALL
1797 int ret
= syscall (__NR_tkill
, lwpid
, signo
);
1798 if (errno
!= ENOSYS
)
1805 return kill (lwpid
, signo
);
1808 /* Handle a GNU/Linux extended wait response. If we see a clone
1809 event, we need to add the new LWP to our list (and not report the
1810 trap to higher layers). This function returns non-zero if the
1811 event should be ignored and we should wait again. If STOPPING is
1812 true, the new LWP remains stopped, otherwise it is continued. */
1815 linux_handle_extended_wait (struct lwp_info
*lp
, int status
,
1818 int pid
= GET_LWP (lp
->ptid
);
1819 struct target_waitstatus
*ourstatus
= &lp
->waitstatus
;
1820 struct lwp_info
*new_lp
= NULL
;
1821 int event
= status
>> 16;
1823 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
1824 || event
== PTRACE_EVENT_CLONE
)
1826 unsigned long new_pid
;
1829 ptrace (PTRACE_GETEVENTMSG
, pid
, 0, &new_pid
);
1831 /* If we haven't already seen the new PID stop, wait for it now. */
1832 if (! pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
1834 /* The new child has a pending SIGSTOP. We can't affect it until it
1835 hits the SIGSTOP, but we're already attached. */
1836 ret
= my_waitpid (new_pid
, &status
,
1837 (event
== PTRACE_EVENT_CLONE
) ? __WCLONE
: 0);
1839 perror_with_name (_("waiting for new child"));
1840 else if (ret
!= new_pid
)
1841 internal_error (__FILE__
, __LINE__
,
1842 _("wait returned unexpected PID %d"), ret
);
1843 else if (!WIFSTOPPED (status
))
1844 internal_error (__FILE__
, __LINE__
,
1845 _("wait returned unexpected status 0x%x"), status
);
1848 ourstatus
->value
.related_pid
= ptid_build (new_pid
, new_pid
, 0);
1850 if (event
== PTRACE_EVENT_FORK
)
1851 ourstatus
->kind
= TARGET_WAITKIND_FORKED
;
1852 else if (event
== PTRACE_EVENT_VFORK
)
1853 ourstatus
->kind
= TARGET_WAITKIND_VFORKED
;
1856 struct cleanup
*old_chain
;
1858 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
1859 new_lp
= add_lwp (BUILD_LWP (new_pid
, GET_PID (lp
->ptid
)));
1861 new_lp
->stopped
= 1;
1863 if (WSTOPSIG (status
) != SIGSTOP
)
1865 /* This can happen if someone starts sending signals to
1866 the new thread before it gets a chance to run, which
1867 have a lower number than SIGSTOP (e.g. SIGUSR1).
1868 This is an unlikely case, and harder to handle for
1869 fork / vfork than for clone, so we do not try - but
1870 we handle it for clone events here. We'll send
1871 the other signal on to the thread below. */
1873 new_lp
->signalled
= 1;
1880 /* Add the new thread to GDB's lists as soon as possible
1883 1) the frontend doesn't have to wait for a stop to
1886 2) we tag it with the correct running state. */
1888 /* If the thread_db layer is active, let it know about
1889 this new thread, and add it to GDB's list. */
1890 if (!thread_db_attach_lwp (new_lp
->ptid
))
1892 /* We're not using thread_db. Add it to GDB's
1894 target_post_attach (GET_LWP (new_lp
->ptid
));
1895 add_thread (new_lp
->ptid
);
1900 set_running (new_lp
->ptid
, 1);
1901 set_executing (new_lp
->ptid
, 1);
1907 new_lp
->stopped
= 0;
1908 new_lp
->resumed
= 1;
1909 ptrace (PTRACE_CONT
, new_pid
, 0,
1910 status
? WSTOPSIG (status
) : 0);
1913 if (debug_linux_nat
)
1914 fprintf_unfiltered (gdb_stdlog
,
1915 "LHEW: Got clone event from LWP %ld, resuming\n",
1916 GET_LWP (lp
->ptid
));
1917 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
1925 if (event
== PTRACE_EVENT_EXEC
)
1927 ourstatus
->kind
= TARGET_WAITKIND_EXECD
;
1928 ourstatus
->value
.execd_pathname
1929 = xstrdup (linux_child_pid_to_exec_file (pid
));
1931 if (linux_parent_pid
)
1933 detach_breakpoints (linux_parent_pid
);
1934 ptrace (PTRACE_DETACH
, linux_parent_pid
, 0, 0);
1936 linux_parent_pid
= 0;
1939 /* At this point, all inserted breakpoints are gone. Doing this
1940 as soon as we detect an exec prevents the badness of deleting
1941 a breakpoint writing the current "shadow contents" to lift
1942 the bp. That shadow is NOT valid after an exec.
1944 Note that we have to do this after the detach_breakpoints
1945 call above, otherwise breakpoints wouldn't be lifted from the
1946 parent on a vfork, because detach_breakpoints would think
1947 that breakpoints are not inserted. */
1948 mark_breakpoints_out ();
1952 internal_error (__FILE__
, __LINE__
,
1953 _("unknown ptrace event %d"), event
);
1956 /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has
1960 wait_lwp (struct lwp_info
*lp
)
1964 int thread_dead
= 0;
1966 gdb_assert (!lp
->stopped
);
1967 gdb_assert (lp
->status
== 0);
1969 pid
= my_waitpid (GET_LWP (lp
->ptid
), &status
, 0);
1970 if (pid
== -1 && errno
== ECHILD
)
1972 pid
= my_waitpid (GET_LWP (lp
->ptid
), &status
, __WCLONE
);
1973 if (pid
== -1 && errno
== ECHILD
)
1975 /* The thread has previously exited. We need to delete it
1976 now because, for some vendor 2.4 kernels with NPTL
1977 support backported, there won't be an exit event unless
1978 it is the main thread. 2.6 kernels will report an exit
1979 event for each thread that exits, as expected. */
1981 if (debug_linux_nat
)
1982 fprintf_unfiltered (gdb_stdlog
, "WL: %s vanished.\n",
1983 target_pid_to_str (lp
->ptid
));
1989 gdb_assert (pid
== GET_LWP (lp
->ptid
));
1991 if (debug_linux_nat
)
1993 fprintf_unfiltered (gdb_stdlog
,
1994 "WL: waitpid %s received %s\n",
1995 target_pid_to_str (lp
->ptid
),
1996 status_to_str (status
));
2000 /* Check if the thread has exited. */
2001 if (WIFEXITED (status
) || WIFSIGNALED (status
))
2004 if (debug_linux_nat
)
2005 fprintf_unfiltered (gdb_stdlog
, "WL: %s exited.\n",
2006 target_pid_to_str (lp
->ptid
));
2015 gdb_assert (WIFSTOPPED (status
));
2017 /* Handle GNU/Linux's extended waitstatus for trace events. */
2018 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
2020 if (debug_linux_nat
)
2021 fprintf_unfiltered (gdb_stdlog
,
2022 "WL: Handling extended status 0x%06x\n",
2024 if (linux_handle_extended_wait (lp
, status
, 1))
2025 return wait_lwp (lp
);
2031 /* Save the most recent siginfo for LP. This is currently only called
2032 for SIGTRAP; some ports use the si_addr field for
2033 target_stopped_data_address. In the future, it may also be used to
2034 restore the siginfo of requeued signals. */
2037 save_siginfo (struct lwp_info
*lp
)
2040 ptrace (PTRACE_GETSIGINFO
, GET_LWP (lp
->ptid
),
2041 (PTRACE_TYPE_ARG3
) 0, &lp
->siginfo
);
2044 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
2047 /* Send a SIGSTOP to LP. */
2050 stop_callback (struct lwp_info
*lp
, void *data
)
2052 if (!lp
->stopped
&& !lp
->signalled
)
2056 if (debug_linux_nat
)
2058 fprintf_unfiltered (gdb_stdlog
,
2059 "SC: kill %s **<SIGSTOP>**\n",
2060 target_pid_to_str (lp
->ptid
));
2063 ret
= kill_lwp (GET_LWP (lp
->ptid
), SIGSTOP
);
2064 if (debug_linux_nat
)
2066 fprintf_unfiltered (gdb_stdlog
,
2067 "SC: lwp kill %d %s\n",
2069 errno
? safe_strerror (errno
) : "ERRNO-OK");
2073 gdb_assert (lp
->status
== 0);
2079 /* Return non-zero if LWP PID has a pending SIGINT. */
2082 linux_nat_has_pending_sigint (int pid
)
2084 sigset_t pending
, blocked
, ignored
;
2087 linux_proc_pending_signals (pid
, &pending
, &blocked
, &ignored
);
2089 if (sigismember (&pending
, SIGINT
)
2090 && !sigismember (&ignored
, SIGINT
))
2096 /* Set a flag in LP indicating that we should ignore its next SIGINT. */
2099 set_ignore_sigint (struct lwp_info
*lp
, void *data
)
2101 /* If a thread has a pending SIGINT, consume it; otherwise, set a
2102 flag to consume the next one. */
2103 if (lp
->stopped
&& lp
->status
!= 0 && WIFSTOPPED (lp
->status
)
2104 && WSTOPSIG (lp
->status
) == SIGINT
)
2107 lp
->ignore_sigint
= 1;
2112 /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag.
2113 This function is called after we know the LWP has stopped; if the LWP
2114 stopped before the expected SIGINT was delivered, then it will never have
2115 arrived. Also, if the signal was delivered to a shared queue and consumed
2116 by a different thread, it will never be delivered to this LWP. */
2119 maybe_clear_ignore_sigint (struct lwp_info
*lp
)
2121 if (!lp
->ignore_sigint
)
2124 if (!linux_nat_has_pending_sigint (GET_LWP (lp
->ptid
)))
2126 if (debug_linux_nat
)
2127 fprintf_unfiltered (gdb_stdlog
,
2128 "MCIS: Clearing bogus flag for %s\n",
2129 target_pid_to_str (lp
->ptid
));
2130 lp
->ignore_sigint
= 0;
2134 /* Wait until LP is stopped. */
2137 stop_wait_callback (struct lwp_info
*lp
, void *data
)
2143 status
= wait_lwp (lp
);
2147 if (lp
->ignore_sigint
&& WIFSTOPPED (status
)
2148 && WSTOPSIG (status
) == SIGINT
)
2150 lp
->ignore_sigint
= 0;
2153 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2154 if (debug_linux_nat
)
2155 fprintf_unfiltered (gdb_stdlog
,
2156 "PTRACE_CONT %s, 0, 0 (%s) (discarding SIGINT)\n",
2157 target_pid_to_str (lp
->ptid
),
2158 errno
? safe_strerror (errno
) : "OK");
2160 return stop_wait_callback (lp
, NULL
);
2163 maybe_clear_ignore_sigint (lp
);
2165 if (WSTOPSIG (status
) != SIGSTOP
)
2167 if (WSTOPSIG (status
) == SIGTRAP
)
2169 /* If a LWP other than the LWP that we're reporting an
2170 event for has hit a GDB breakpoint (as opposed to
2171 some random trap signal), then just arrange for it to
2172 hit it again later. We don't keep the SIGTRAP status
2173 and don't forward the SIGTRAP signal to the LWP. We
2174 will handle the current event, eventually we will
2175 resume all LWPs, and this one will get its breakpoint
2178 If we do not do this, then we run the risk that the
2179 user will delete or disable the breakpoint, but the
2180 thread will have already tripped on it. */
2182 /* Save the trap's siginfo in case we need it later. */
2185 /* Now resume this LWP and get the SIGSTOP event. */
2187 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2188 if (debug_linux_nat
)
2190 fprintf_unfiltered (gdb_stdlog
,
2191 "PTRACE_CONT %s, 0, 0 (%s)\n",
2192 target_pid_to_str (lp
->ptid
),
2193 errno
? safe_strerror (errno
) : "OK");
2195 fprintf_unfiltered (gdb_stdlog
,
2196 "SWC: Candidate SIGTRAP event in %s\n",
2197 target_pid_to_str (lp
->ptid
));
2199 /* Hold this event/waitstatus while we check to see if
2200 there are any more (we still want to get that SIGSTOP). */
2201 stop_wait_callback (lp
, NULL
);
2203 /* Hold the SIGTRAP for handling by linux_nat_wait. If
2204 there's another event, throw it back into the
2208 if (debug_linux_nat
)
2209 fprintf_unfiltered (gdb_stdlog
,
2210 "SWC: kill %s, %s\n",
2211 target_pid_to_str (lp
->ptid
),
2212 status_to_str ((int) status
));
2213 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (lp
->status
));
2216 /* Save the sigtrap event. */
2217 lp
->status
= status
;
2222 /* The thread was stopped with a signal other than
2223 SIGSTOP, and didn't accidentally trip a breakpoint. */
2225 if (debug_linux_nat
)
2227 fprintf_unfiltered (gdb_stdlog
,
2228 "SWC: Pending event %s in %s\n",
2229 status_to_str ((int) status
),
2230 target_pid_to_str (lp
->ptid
));
2232 /* Now resume this LWP and get the SIGSTOP event. */
2234 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2235 if (debug_linux_nat
)
2236 fprintf_unfiltered (gdb_stdlog
,
2237 "SWC: PTRACE_CONT %s, 0, 0 (%s)\n",
2238 target_pid_to_str (lp
->ptid
),
2239 errno
? safe_strerror (errno
) : "OK");
2241 /* Hold this event/waitstatus while we check to see if
2242 there are any more (we still want to get that SIGSTOP). */
2243 stop_wait_callback (lp
, NULL
);
2245 /* If the lp->status field is still empty, use it to
2246 hold this event. If not, then this event must be
2247 returned to the event queue of the LWP. */
2250 if (debug_linux_nat
)
2252 fprintf_unfiltered (gdb_stdlog
,
2253 "SWC: kill %s, %s\n",
2254 target_pid_to_str (lp
->ptid
),
2255 status_to_str ((int) status
));
2257 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (status
));
2260 lp
->status
= status
;
2266 /* We caught the SIGSTOP that we intended to catch, so
2267 there's no SIGSTOP pending. */
2276 /* Return non-zero if LP has a wait status pending. */
2279 status_callback (struct lwp_info
*lp
, void *data
)
2281 /* Only report a pending wait status if we pretend that this has
2282 indeed been resumed. */
2283 /* We check for lp->waitstatus in addition to lp->status, because we
2284 can have pending process exits recorded in lp->waitstatus, and
2285 W_EXITCODE(0,0) == 0. */
2286 return ((lp
->status
!= 0
2287 || lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
2291 /* Return non-zero if LP isn't stopped. */
2294 running_callback (struct lwp_info
*lp
, void *data
)
2296 return (lp
->stopped
== 0 || (lp
->status
!= 0 && lp
->resumed
));
2299 /* Count the LWP's that have had events. */
2302 count_events_callback (struct lwp_info
*lp
, void *data
)
2306 gdb_assert (count
!= NULL
);
2308 /* Count only resumed LWPs that have a SIGTRAP event pending. */
2309 if (lp
->status
!= 0 && lp
->resumed
2310 && WIFSTOPPED (lp
->status
) && WSTOPSIG (lp
->status
) == SIGTRAP
)
2316 /* Select the LWP (if any) that is currently being single-stepped. */
2319 select_singlestep_lwp_callback (struct lwp_info
*lp
, void *data
)
2321 if (lp
->step
&& lp
->status
!= 0)
2327 /* Select the Nth LWP that has had a SIGTRAP event. */
2330 select_event_lwp_callback (struct lwp_info
*lp
, void *data
)
2332 int *selector
= data
;
2334 gdb_assert (selector
!= NULL
);
2336 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2337 if (lp
->status
!= 0 && lp
->resumed
2338 && WIFSTOPPED (lp
->status
) && WSTOPSIG (lp
->status
) == SIGTRAP
)
2339 if ((*selector
)-- == 0)
2346 cancel_breakpoint (struct lwp_info
*lp
)
2348 /* Arrange for a breakpoint to be hit again later. We don't keep
2349 the SIGTRAP status and don't forward the SIGTRAP signal to the
2350 LWP. We will handle the current event, eventually we will resume
2351 this LWP, and this breakpoint will trap again.
2353 If we do not do this, then we run the risk that the user will
2354 delete or disable the breakpoint, but the LWP will have already
2357 struct regcache
*regcache
= get_thread_regcache (lp
->ptid
);
2358 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2361 pc
= regcache_read_pc (regcache
) - gdbarch_decr_pc_after_break (gdbarch
);
2362 if (breakpoint_inserted_here_p (pc
))
2364 if (debug_linux_nat
)
2365 fprintf_unfiltered (gdb_stdlog
,
2366 "CB: Push back breakpoint for %s\n",
2367 target_pid_to_str (lp
->ptid
));
2369 /* Back up the PC if necessary. */
2370 if (gdbarch_decr_pc_after_break (gdbarch
))
2371 regcache_write_pc (regcache
, pc
);
2379 cancel_breakpoints_callback (struct lwp_info
*lp
, void *data
)
2381 struct lwp_info
*event_lp
= data
;
2383 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
2387 /* If a LWP other than the LWP that we're reporting an event for has
2388 hit a GDB breakpoint (as opposed to some random trap signal),
2389 then just arrange for it to hit it again later. We don't keep
2390 the SIGTRAP status and don't forward the SIGTRAP signal to the
2391 LWP. We will handle the current event, eventually we will resume
2392 all LWPs, and this one will get its breakpoint trap again.
2394 If we do not do this, then we run the risk that the user will
2395 delete or disable the breakpoint, but the LWP will have already
2399 && WIFSTOPPED (lp
->status
) && WSTOPSIG (lp
->status
) == SIGTRAP
2400 && cancel_breakpoint (lp
))
2401 /* Throw away the SIGTRAP. */
2407 /* Select one LWP out of those that have events pending. */
2410 select_event_lwp (ptid_t filter
, struct lwp_info
**orig_lp
, int *status
)
2413 int random_selector
;
2414 struct lwp_info
*event_lp
;
2416 /* Record the wait status for the original LWP. */
2417 (*orig_lp
)->status
= *status
;
2419 /* Give preference to any LWP that is being single-stepped. */
2420 event_lp
= iterate_over_lwps (filter
,
2421 select_singlestep_lwp_callback
, NULL
);
2422 if (event_lp
!= NULL
)
2424 if (debug_linux_nat
)
2425 fprintf_unfiltered (gdb_stdlog
,
2426 "SEL: Select single-step %s\n",
2427 target_pid_to_str (event_lp
->ptid
));
2431 /* No single-stepping LWP. Select one at random, out of those
2432 which have had SIGTRAP events. */
2434 /* First see how many SIGTRAP events we have. */
2435 iterate_over_lwps (filter
, count_events_callback
, &num_events
);
2437 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
2438 random_selector
= (int)
2439 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2441 if (debug_linux_nat
&& num_events
> 1)
2442 fprintf_unfiltered (gdb_stdlog
,
2443 "SEL: Found %d SIGTRAP events, selecting #%d\n",
2444 num_events
, random_selector
);
2446 event_lp
= iterate_over_lwps (filter
,
2447 select_event_lwp_callback
,
2451 if (event_lp
!= NULL
)
2453 /* Switch the event LWP. */
2454 *orig_lp
= event_lp
;
2455 *status
= event_lp
->status
;
2458 /* Flush the wait status for the event LWP. */
2459 (*orig_lp
)->status
= 0;
2462 /* Return non-zero if LP has been resumed. */
2465 resumed_callback (struct lwp_info
*lp
, void *data
)
2470 /* Stop an active thread, verify it still exists, then resume it. */
2473 stop_and_resume_callback (struct lwp_info
*lp
, void *data
)
2475 struct lwp_info
*ptr
;
2477 if (!lp
->stopped
&& !lp
->signalled
)
2479 stop_callback (lp
, NULL
);
2480 stop_wait_callback (lp
, NULL
);
2481 /* Resume if the lwp still exists. */
2482 for (ptr
= lwp_list
; ptr
; ptr
= ptr
->next
)
2485 resume_callback (lp
, NULL
);
2486 resume_set_callback (lp
, NULL
);
2492 /* Check if we should go on and pass this event to common code.
2493 Return the affected lwp if we are, or NULL otherwise. */
2494 static struct lwp_info
*
2495 linux_nat_filter_event (int lwpid
, int status
, int options
)
2497 struct lwp_info
*lp
;
2499 lp
= find_lwp_pid (pid_to_ptid (lwpid
));
2501 /* Check for stop events reported by a process we didn't already
2502 know about - anything not already in our LWP list.
2504 If we're expecting to receive stopped processes after
2505 fork, vfork, and clone events, then we'll just add the
2506 new one to our list and go back to waiting for the event
2507 to be reported - the stopped process might be returned
2508 from waitpid before or after the event is. */
2509 if (WIFSTOPPED (status
) && !lp
)
2511 linux_record_stopped_pid (lwpid
, status
);
2515 /* Make sure we don't report an event for the exit of an LWP not in
2516 our list, i.e. not part of the current process. This can happen
2517 if we detach from a program we original forked and then it
2519 if (!WIFSTOPPED (status
) && !lp
)
2522 /* NOTE drow/2003-06-17: This code seems to be meant for debugging
2523 CLONE_PTRACE processes which do not use the thread library -
2524 otherwise we wouldn't find the new LWP this way. That doesn't
2525 currently work, and the following code is currently unreachable
2526 due to the two blocks above. If it's fixed some day, this code
2527 should be broken out into a function so that we can also pick up
2528 LWPs from the new interface. */
2531 lp
= add_lwp (BUILD_LWP (lwpid
, GET_PID (inferior_ptid
)));
2532 if (options
& __WCLONE
)
2535 gdb_assert (WIFSTOPPED (status
)
2536 && WSTOPSIG (status
) == SIGSTOP
);
2539 if (!in_thread_list (inferior_ptid
))
2541 inferior_ptid
= BUILD_LWP (GET_PID (inferior_ptid
),
2542 GET_PID (inferior_ptid
));
2543 add_thread (inferior_ptid
);
2546 add_thread (lp
->ptid
);
2549 /* Save the trap's siginfo in case we need it later. */
2550 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
)
2553 /* Handle GNU/Linux's extended waitstatus for trace events. */
2554 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
2556 if (debug_linux_nat
)
2557 fprintf_unfiltered (gdb_stdlog
,
2558 "LLW: Handling extended status 0x%06x\n",
2560 if (linux_handle_extended_wait (lp
, status
, 0))
2564 /* Check if the thread has exited. */
2565 if ((WIFEXITED (status
) || WIFSIGNALED (status
))
2566 && num_lwps (GET_PID (lp
->ptid
)) > 1)
2568 /* If this is the main thread, we must stop all threads and verify
2569 if they are still alive. This is because in the nptl thread model
2570 on Linux 2.4, there is no signal issued for exiting LWPs
2571 other than the main thread. We only get the main thread exit
2572 signal once all child threads have already exited. If we
2573 stop all the threads and use the stop_wait_callback to check
2574 if they have exited we can determine whether this signal
2575 should be ignored or whether it means the end of the debugged
2576 application, regardless of which threading model is being
2578 if (GET_PID (lp
->ptid
) == GET_LWP (lp
->ptid
))
2581 iterate_over_lwps (pid_to_ptid (GET_PID (lp
->ptid
)),
2582 stop_and_resume_callback
, NULL
);
2585 if (debug_linux_nat
)
2586 fprintf_unfiltered (gdb_stdlog
,
2587 "LLW: %s exited.\n",
2588 target_pid_to_str (lp
->ptid
));
2590 if (num_lwps (GET_PID (lp
->ptid
)) > 1)
2592 /* If there is at least one more LWP, then the exit signal
2593 was not the end of the debugged application and should be
2600 /* Check if the current LWP has previously exited. In the nptl
2601 thread model, LWPs other than the main thread do not issue
2602 signals when they exit so we must check whenever the thread has
2603 stopped. A similar check is made in stop_wait_callback(). */
2604 if (num_lwps (GET_PID (lp
->ptid
)) > 1 && !linux_thread_alive (lp
->ptid
))
2606 ptid_t ptid
= pid_to_ptid (GET_PID (lp
->ptid
));
2608 if (debug_linux_nat
)
2609 fprintf_unfiltered (gdb_stdlog
,
2610 "LLW: %s exited.\n",
2611 target_pid_to_str (lp
->ptid
));
2615 /* Make sure there is at least one thread running. */
2616 gdb_assert (iterate_over_lwps (ptid
, running_callback
, NULL
));
2618 /* Discard the event. */
2622 /* Make sure we don't report a SIGSTOP that we sent ourselves in
2623 an attempt to stop an LWP. */
2625 && WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGSTOP
)
2627 if (debug_linux_nat
)
2628 fprintf_unfiltered (gdb_stdlog
,
2629 "LLW: Delayed SIGSTOP caught for %s.\n",
2630 target_pid_to_str (lp
->ptid
));
2632 /* This is a delayed SIGSTOP. */
2635 registers_changed ();
2637 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
2638 lp
->step
, TARGET_SIGNAL_0
);
2639 if (debug_linux_nat
)
2640 fprintf_unfiltered (gdb_stdlog
,
2641 "LLW: %s %s, 0, 0 (discard SIGSTOP)\n",
2643 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
2644 target_pid_to_str (lp
->ptid
));
2647 gdb_assert (lp
->resumed
);
2649 /* Discard the event. */
2653 /* Make sure we don't report a SIGINT that we have already displayed
2654 for another thread. */
2655 if (lp
->ignore_sigint
2656 && WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGINT
)
2658 if (debug_linux_nat
)
2659 fprintf_unfiltered (gdb_stdlog
,
2660 "LLW: Delayed SIGINT caught for %s.\n",
2661 target_pid_to_str (lp
->ptid
));
2663 /* This is a delayed SIGINT. */
2664 lp
->ignore_sigint
= 0;
2666 registers_changed ();
2667 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
2668 lp
->step
, TARGET_SIGNAL_0
);
2669 if (debug_linux_nat
)
2670 fprintf_unfiltered (gdb_stdlog
,
2671 "LLW: %s %s, 0, 0 (discard SIGINT)\n",
2673 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
2674 target_pid_to_str (lp
->ptid
));
2677 gdb_assert (lp
->resumed
);
2679 /* Discard the event. */
2683 /* An interesting event. */
2689 linux_nat_wait_1 (struct target_ops
*ops
,
2690 ptid_t ptid
, struct target_waitstatus
*ourstatus
)
2692 static sigset_t prev_mask
;
2693 struct lwp_info
*lp
= NULL
;
2698 if (debug_linux_nat_async
)
2699 fprintf_unfiltered (gdb_stdlog
, "LLW: enter\n");
2701 /* The first time we get here after starting a new inferior, we may
2702 not have added it to the LWP list yet - this is the earliest
2703 moment at which we know its PID. */
2704 if (ptid_is_pid (inferior_ptid
))
2706 /* Upgrade the main thread's ptid. */
2707 thread_change_ptid (inferior_ptid
,
2708 BUILD_LWP (GET_PID (inferior_ptid
),
2709 GET_PID (inferior_ptid
)));
2711 lp
= add_lwp (inferior_ptid
);
2715 /* Make sure SIGCHLD is blocked. */
2716 block_child_signals (&prev_mask
);
2718 if (ptid_equal (ptid
, minus_one_ptid
))
2720 else if (ptid_is_pid (ptid
))
2721 /* A request to wait for a specific tgid. This is not possible
2722 with waitpid, so instead, we wait for any child, and leave
2723 children we're not interested in right now with a pending
2724 status to report later. */
2727 pid
= GET_LWP (ptid
);
2733 /* Make sure there is at least one LWP that has been resumed. */
2734 gdb_assert (iterate_over_lwps (ptid
, resumed_callback
, NULL
));
2736 /* First check if there is a LWP with a wait status pending. */
2739 /* Any LWP that's been resumed will do. */
2740 lp
= iterate_over_lwps (ptid
, status_callback
, NULL
);
2743 status
= lp
->status
;
2746 if (debug_linux_nat
&& status
)
2747 fprintf_unfiltered (gdb_stdlog
,
2748 "LLW: Using pending wait status %s for %s.\n",
2749 status_to_str (status
),
2750 target_pid_to_str (lp
->ptid
));
2753 /* But if we don't find one, we'll have to wait, and check both
2754 cloned and uncloned processes. We start with the cloned
2756 options
= __WCLONE
| WNOHANG
;
2758 else if (is_lwp (ptid
))
2760 if (debug_linux_nat
)
2761 fprintf_unfiltered (gdb_stdlog
,
2762 "LLW: Waiting for specific LWP %s.\n",
2763 target_pid_to_str (ptid
));
2765 /* We have a specific LWP to check. */
2766 lp
= find_lwp_pid (ptid
);
2768 status
= lp
->status
;
2771 if (debug_linux_nat
&& status
)
2772 fprintf_unfiltered (gdb_stdlog
,
2773 "LLW: Using pending wait status %s for %s.\n",
2774 status_to_str (status
),
2775 target_pid_to_str (lp
->ptid
));
2777 /* If we have to wait, take into account whether PID is a cloned
2778 process or not. And we have to convert it to something that
2779 the layer beneath us can understand. */
2780 options
= lp
->cloned
? __WCLONE
: 0;
2781 pid
= GET_LWP (ptid
);
2783 /* We check for lp->waitstatus in addition to lp->status,
2784 because we can have pending process exits recorded in
2785 lp->status and W_EXITCODE(0,0) == 0. We should probably have
2786 an additional lp->status_p flag. */
2787 if (status
== 0 && lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
)
2791 if (lp
&& lp
->signalled
)
2793 /* A pending SIGSTOP may interfere with the normal stream of
2794 events. In a typical case where interference is a problem,
2795 we have a SIGSTOP signal pending for LWP A while
2796 single-stepping it, encounter an event in LWP B, and take the
2797 pending SIGSTOP while trying to stop LWP A. After processing
2798 the event in LWP B, LWP A is continued, and we'll never see
2799 the SIGTRAP associated with the last time we were
2800 single-stepping LWP A. */
2802 /* Resume the thread. It should halt immediately returning the
2804 registers_changed ();
2805 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
2806 lp
->step
, TARGET_SIGNAL_0
);
2807 if (debug_linux_nat
)
2808 fprintf_unfiltered (gdb_stdlog
,
2809 "LLW: %s %s, 0, 0 (expect SIGSTOP)\n",
2810 lp
->step
? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
2811 target_pid_to_str (lp
->ptid
));
2813 gdb_assert (lp
->resumed
);
2815 /* This should catch the pending SIGSTOP. */
2816 stop_wait_callback (lp
, NULL
);
2819 if (!target_can_async_p ())
2821 /* Causes SIGINT to be passed on to the attached process. */
2825 if (target_can_async_p ())
2826 options
|= WNOHANG
; /* In async mode, don't block. */
2832 lwpid
= my_waitpid (pid
, &status
, options
);
2836 gdb_assert (pid
== -1 || lwpid
== pid
);
2838 if (debug_linux_nat
)
2840 fprintf_unfiltered (gdb_stdlog
,
2841 "LLW: waitpid %ld received %s\n",
2842 (long) lwpid
, status_to_str (status
));
2845 lp
= linux_nat_filter_event (lwpid
, status
, options
);
2848 && ptid_is_pid (ptid
)
2849 && ptid_get_pid (lp
->ptid
) != ptid_get_pid (ptid
))
2851 if (debug_linux_nat
)
2852 fprintf (stderr
, "LWP %ld got an event %06x, leaving pending.\n",
2853 ptid_get_lwp (lp
->ptid
), status
);
2855 if (WIFSTOPPED (status
))
2857 if (WSTOPSIG (status
) != SIGSTOP
)
2859 lp
->status
= status
;
2861 stop_callback (lp
, NULL
);
2863 /* Resume in order to collect the sigstop. */
2864 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2866 stop_wait_callback (lp
, NULL
);
2874 else if (WIFEXITED (status
) || WIFSIGNALED (status
))
2876 if (debug_linux_nat
)
2877 fprintf (stderr
, "Process %ld exited while stopping LWPs\n",
2878 ptid_get_lwp (lp
->ptid
));
2880 /* This was the last lwp in the process. Since
2881 events are serialized to GDB core, and we can't
2882 report this one right now, but GDB core and the
2883 other target layers will want to be notified
2884 about the exit code/signal, leave the status
2885 pending for the next time we're able to report
2887 lp
->status
= status
;
2889 /* Prevent trying to stop this thread again. We'll
2890 never try to resume it because it has a pending
2894 /* Dead LWP's aren't expected to reported a pending
2898 /* Store the pending event in the waitstatus as
2899 well, because W_EXITCODE(0,0) == 0. */
2900 store_waitstatus (&lp
->waitstatus
, status
);
2914 /* waitpid did return something. Restart over. */
2915 options
|= __WCLONE
;
2923 /* Alternate between checking cloned and uncloned processes. */
2924 options
^= __WCLONE
;
2926 /* And every time we have checked both:
2927 In async mode, return to event loop;
2928 In sync mode, suspend waiting for a SIGCHLD signal. */
2929 if (options
& __WCLONE
)
2931 if (target_can_async_p ())
2933 /* No interesting event. */
2934 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2936 if (debug_linux_nat_async
)
2937 fprintf_unfiltered (gdb_stdlog
, "LLW: exit (ignore)\n");
2939 restore_child_signals_mask (&prev_mask
);
2940 return minus_one_ptid
;
2943 sigsuspend (&suspend_mask
);
2947 /* We shouldn't end up here unless we want to try again. */
2948 gdb_assert (lp
== NULL
);
2951 if (!target_can_async_p ())
2952 clear_sigint_trap ();
2956 /* Don't report signals that GDB isn't interested in, such as
2957 signals that are neither printed nor stopped upon. Stopping all
2958 threads can be a bit time-consuming so if we want decent
2959 performance with heavily multi-threaded programs, especially when
2960 they're using a high frequency timer, we'd better avoid it if we
2963 if (WIFSTOPPED (status
))
2965 int signo
= target_signal_from_host (WSTOPSIG (status
));
2966 struct inferior
*inf
;
2968 inf
= find_inferior_pid (ptid_get_pid (lp
->ptid
));
2971 /* Defer to common code if we get a signal while
2972 single-stepping, since that may need special care, e.g. to
2973 skip the signal handler, or, if we're gaining control of the
2976 && inf
->stop_soon
== NO_STOP_QUIETLY
2977 && signal_stop_state (signo
) == 0
2978 && signal_print_state (signo
) == 0
2979 && signal_pass_state (signo
) == 1)
2981 /* FIMXE: kettenis/2001-06-06: Should we resume all threads
2982 here? It is not clear we should. GDB may not expect
2983 other threads to run. On the other hand, not resuming
2984 newly attached threads may cause an unwanted delay in
2985 getting them running. */
2986 registers_changed ();
2987 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
2989 if (debug_linux_nat
)
2990 fprintf_unfiltered (gdb_stdlog
,
2991 "LLW: %s %s, %s (preempt 'handle')\n",
2993 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
2994 target_pid_to_str (lp
->ptid
),
2995 signo
? strsignal (signo
) : "0");
3002 /* Only do the below in all-stop, as we currently use SIGINT
3003 to implement target_stop (see linux_nat_stop) in
3005 if (signo
== TARGET_SIGNAL_INT
&& signal_pass_state (signo
) == 0)
3007 /* If ^C/BREAK is typed at the tty/console, SIGINT gets
3008 forwarded to the entire process group, that is, all LWPs
3009 will receive it - unless they're using CLONE_THREAD to
3010 share signals. Since we only want to report it once, we
3011 mark it as ignored for all LWPs except this one. */
3012 iterate_over_lwps (pid_to_ptid (ptid_get_pid (ptid
)),
3013 set_ignore_sigint
, NULL
);
3014 lp
->ignore_sigint
= 0;
3017 maybe_clear_ignore_sigint (lp
);
3021 /* This LWP is stopped now. */
3024 if (debug_linux_nat
)
3025 fprintf_unfiltered (gdb_stdlog
, "LLW: Candidate event %s in %s.\n",
3026 status_to_str (status
), target_pid_to_str (lp
->ptid
));
3030 /* Now stop all other LWP's ... */
3031 iterate_over_lwps (minus_one_ptid
, stop_callback
, NULL
);
3033 /* ... and wait until all of them have reported back that
3034 they're no longer running. */
3035 iterate_over_lwps (minus_one_ptid
, stop_wait_callback
, NULL
);
3037 /* If we're not waiting for a specific LWP, choose an event LWP
3038 from among those that have had events. Giving equal priority
3039 to all LWPs that have had events helps prevent
3042 select_event_lwp (ptid
, &lp
, &status
);
3045 /* Now that we've selected our final event LWP, cancel any
3046 breakpoints in other LWPs that have hit a GDB breakpoint. See
3047 the comment in cancel_breakpoints_callback to find out why. */
3048 iterate_over_lwps (minus_one_ptid
, cancel_breakpoints_callback
, lp
);
3050 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
)
3052 if (debug_linux_nat
)
3053 fprintf_unfiltered (gdb_stdlog
,
3054 "LLW: trap ptid is %s.\n",
3055 target_pid_to_str (lp
->ptid
));
3058 if (lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3060 *ourstatus
= lp
->waitstatus
;
3061 lp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3064 store_waitstatus (ourstatus
, status
);
3066 if (debug_linux_nat_async
)
3067 fprintf_unfiltered (gdb_stdlog
, "LLW: exit\n");
3069 restore_child_signals_mask (&prev_mask
);
3074 linux_nat_wait (struct target_ops
*ops
,
3075 ptid_t ptid
, struct target_waitstatus
*ourstatus
)
3079 if (debug_linux_nat
)
3080 fprintf_unfiltered (gdb_stdlog
, "linux_nat_wait: [%s]\n", target_pid_to_str (ptid
));
3082 /* Flush the async file first. */
3083 if (target_can_async_p ())
3084 async_file_flush ();
3086 event_ptid
= linux_nat_wait_1 (ops
, ptid
, ourstatus
);
3088 /* If we requested any event, and something came out, assume there
3089 may be more. If we requested a specific lwp or process, also
3090 assume there may be more. */
3091 if (target_can_async_p ()
3092 && (ourstatus
->kind
!= TARGET_WAITKIND_IGNORE
3093 || !ptid_equal (ptid
, minus_one_ptid
)))
3096 /* Get ready for the next event. */
3097 if (target_can_async_p ())
3098 target_async (inferior_event_handler
, 0);
3104 kill_callback (struct lwp_info
*lp
, void *data
)
3107 ptrace (PTRACE_KILL
, GET_LWP (lp
->ptid
), 0, 0);
3108 if (debug_linux_nat
)
3109 fprintf_unfiltered (gdb_stdlog
,
3110 "KC: PTRACE_KILL %s, 0, 0 (%s)\n",
3111 target_pid_to_str (lp
->ptid
),
3112 errno
? safe_strerror (errno
) : "OK");
3118 kill_wait_callback (struct lwp_info
*lp
, void *data
)
3122 /* We must make sure that there are no pending events (delayed
3123 SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current
3124 program doesn't interfere with any following debugging session. */
3126 /* For cloned processes we must check both with __WCLONE and
3127 without, since the exit status of a cloned process isn't reported
3133 pid
= my_waitpid (GET_LWP (lp
->ptid
), NULL
, __WCLONE
);
3134 if (pid
!= (pid_t
) -1)
3136 if (debug_linux_nat
)
3137 fprintf_unfiltered (gdb_stdlog
,
3138 "KWC: wait %s received unknown.\n",
3139 target_pid_to_str (lp
->ptid
));
3140 /* The Linux kernel sometimes fails to kill a thread
3141 completely after PTRACE_KILL; that goes from the stop
3142 point in do_fork out to the one in
3143 get_signal_to_deliever and waits again. So kill it
3145 kill_callback (lp
, NULL
);
3148 while (pid
== GET_LWP (lp
->ptid
));
3150 gdb_assert (pid
== -1 && errno
== ECHILD
);
3155 pid
= my_waitpid (GET_LWP (lp
->ptid
), NULL
, 0);
3156 if (pid
!= (pid_t
) -1)
3158 if (debug_linux_nat
)
3159 fprintf_unfiltered (gdb_stdlog
,
3160 "KWC: wait %s received unk.\n",
3161 target_pid_to_str (lp
->ptid
));
3162 /* See the call to kill_callback above. */
3163 kill_callback (lp
, NULL
);
3166 while (pid
== GET_LWP (lp
->ptid
));
3168 gdb_assert (pid
== -1 && errno
== ECHILD
);
3173 linux_nat_kill (struct target_ops
*ops
)
3175 struct target_waitstatus last
;
3179 /* If we're stopped while forking and we haven't followed yet,
3180 kill the other task. We need to do this first because the
3181 parent will be sleeping if this is a vfork. */
3183 get_last_target_status (&last_ptid
, &last
);
3185 if (last
.kind
== TARGET_WAITKIND_FORKED
3186 || last
.kind
== TARGET_WAITKIND_VFORKED
)
3188 ptrace (PT_KILL
, PIDGET (last
.value
.related_pid
), 0, 0);
3192 if (forks_exist_p ())
3193 linux_fork_killall ();
3196 ptid_t ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
3197 /* Stop all threads before killing them, since ptrace requires
3198 that the thread is stopped to sucessfully PTRACE_KILL. */
3199 iterate_over_lwps (ptid
, stop_callback
, NULL
);
3200 /* ... and wait until all of them have reported back that
3201 they're no longer running. */
3202 iterate_over_lwps (ptid
, stop_wait_callback
, NULL
);
3204 /* Kill all LWP's ... */
3205 iterate_over_lwps (ptid
, kill_callback
, NULL
);
3207 /* ... and wait until we've flushed all events. */
3208 iterate_over_lwps (ptid
, kill_wait_callback
, NULL
);
3211 target_mourn_inferior ();
3215 linux_nat_mourn_inferior (struct target_ops
*ops
)
3217 purge_lwp_list (ptid_get_pid (inferior_ptid
));
3219 if (! forks_exist_p ())
3220 /* Normal case, no other forks available. */
3221 linux_ops
->to_mourn_inferior (ops
);
3223 /* Multi-fork case. The current inferior_ptid has exited, but
3224 there are other viable forks to debug. Delete the exiting
3225 one and context-switch to the first available. */
3226 linux_fork_mourn_inferior ();
3229 /* Convert a native/host siginfo object, into/from the siginfo in the
3230 layout of the inferiors' architecture. */
3233 siginfo_fixup (struct siginfo
*siginfo
, gdb_byte
*inf_siginfo
, int direction
)
3237 if (linux_nat_siginfo_fixup
!= NULL
)
3238 done
= linux_nat_siginfo_fixup (siginfo
, inf_siginfo
, direction
);
3240 /* If there was no callback, or the callback didn't do anything,
3241 then just do a straight memcpy. */
3245 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
3247 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
3252 linux_xfer_siginfo (struct target_ops
*ops
, enum target_object object
,
3253 const char *annex
, gdb_byte
*readbuf
,
3254 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
3257 struct siginfo siginfo
;
3258 gdb_byte inf_siginfo
[sizeof (struct siginfo
)];
3260 gdb_assert (object
== TARGET_OBJECT_SIGNAL_INFO
);
3261 gdb_assert (readbuf
|| writebuf
);
3263 pid
= GET_LWP (inferior_ptid
);
3265 pid
= GET_PID (inferior_ptid
);
3267 if (offset
> sizeof (siginfo
))
3271 ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
);
3275 /* When GDB is built as a 64-bit application, ptrace writes into
3276 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
3277 inferior with a 64-bit GDB should look the same as debugging it
3278 with a 32-bit GDB, we need to convert it. GDB core always sees
3279 the converted layout, so any read/write will have to be done
3281 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
3283 if (offset
+ len
> sizeof (siginfo
))
3284 len
= sizeof (siginfo
) - offset
;
3286 if (readbuf
!= NULL
)
3287 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
3290 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
3292 /* Convert back to ptrace layout before flushing it out. */
3293 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
3296 ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
);
3305 linux_nat_xfer_partial (struct target_ops
*ops
, enum target_object object
,
3306 const char *annex
, gdb_byte
*readbuf
,
3307 const gdb_byte
*writebuf
,
3308 ULONGEST offset
, LONGEST len
)
3310 struct cleanup
*old_chain
;
3313 if (object
== TARGET_OBJECT_SIGNAL_INFO
)
3314 return linux_xfer_siginfo (ops
, object
, annex
, readbuf
, writebuf
,
3317 old_chain
= save_inferior_ptid ();
3319 if (is_lwp (inferior_ptid
))
3320 inferior_ptid
= pid_to_ptid (GET_LWP (inferior_ptid
));
3322 xfer
= linux_ops
->to_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
3325 do_cleanups (old_chain
);
3330 linux_thread_alive (ptid_t ptid
)
3334 gdb_assert (is_lwp (ptid
));
3336 /* Send signal 0 instead of anything ptrace, because ptracing a
3337 running thread errors out claiming that the thread doesn't
3339 err
= kill_lwp (GET_LWP (ptid
), 0);
3341 if (debug_linux_nat
)
3342 fprintf_unfiltered (gdb_stdlog
,
3343 "LLTA: KILL(SIG0) %s (%s)\n",
3344 target_pid_to_str (ptid
),
3345 err
? safe_strerror (err
) : "OK");
3354 linux_nat_thread_alive (struct target_ops
*ops
, ptid_t ptid
)
3356 return linux_thread_alive (ptid
);
3360 linux_nat_pid_to_str (struct target_ops
*ops
, ptid_t ptid
)
3362 static char buf
[64];
3365 && (GET_PID (ptid
) != GET_LWP (ptid
)
3366 || num_lwps (GET_PID (ptid
)) > 1))
3368 snprintf (buf
, sizeof (buf
), "LWP %ld", GET_LWP (ptid
));
3372 return normal_pid_to_str (ptid
);
3375 /* Accepts an integer PID; Returns a string representing a file that
3376 can be opened to get the symbols for the child process. */
3379 linux_child_pid_to_exec_file (int pid
)
3381 char *name1
, *name2
;
3383 name1
= xmalloc (MAXPATHLEN
);
3384 name2
= xmalloc (MAXPATHLEN
);
3385 make_cleanup (xfree
, name1
);
3386 make_cleanup (xfree
, name2
);
3387 memset (name2
, 0, MAXPATHLEN
);
3389 sprintf (name1
, "/proc/%d/exe", pid
);
3390 if (readlink (name1
, name2
, MAXPATHLEN
) > 0)
3396 /* Service function for corefiles and info proc. */
3399 read_mapping (FILE *mapfile
,
3404 char *device
, long long *inode
, char *filename
)
3406 int ret
= fscanf (mapfile
, "%llx-%llx %s %llx %s %llx",
3407 addr
, endaddr
, permissions
, offset
, device
, inode
);
3410 if (ret
> 0 && ret
!= EOF
)
3412 /* Eat everything up to EOL for the filename. This will prevent
3413 weird filenames (such as one with embedded whitespace) from
3414 confusing this code. It also makes this code more robust in
3415 respect to annotations the kernel may add after the filename.
3417 Note the filename is used for informational purposes
3419 ret
+= fscanf (mapfile
, "%[^\n]\n", filename
);
3422 return (ret
!= 0 && ret
!= EOF
);
3425 /* Fills the "to_find_memory_regions" target vector. Lists the memory
3426 regions in the inferior for a corefile. */
3429 linux_nat_find_memory_regions (int (*func
) (CORE_ADDR
,
3431 int, int, int, void *), void *obfd
)
3433 int pid
= PIDGET (inferior_ptid
);
3434 char mapsfilename
[MAXPATHLEN
];
3436 long long addr
, endaddr
, size
, offset
, inode
;
3437 char permissions
[8], device
[8], filename
[MAXPATHLEN
];
3438 int read
, write
, exec
;
3440 struct cleanup
*cleanup
;
3442 /* Compose the filename for the /proc memory map, and open it. */
3443 sprintf (mapsfilename
, "/proc/%d/maps", pid
);
3444 if ((mapsfile
= fopen (mapsfilename
, "r")) == NULL
)
3445 error (_("Could not open %s."), mapsfilename
);
3446 cleanup
= make_cleanup_fclose (mapsfile
);
3449 fprintf_filtered (gdb_stdout
,
3450 "Reading memory regions from %s\n", mapsfilename
);
3452 /* Now iterate until end-of-file. */
3453 while (read_mapping (mapsfile
, &addr
, &endaddr
, &permissions
[0],
3454 &offset
, &device
[0], &inode
, &filename
[0]))
3456 size
= endaddr
- addr
;
3458 /* Get the segment's permissions. */
3459 read
= (strchr (permissions
, 'r') != 0);
3460 write
= (strchr (permissions
, 'w') != 0);
3461 exec
= (strchr (permissions
, 'x') != 0);
3465 fprintf_filtered (gdb_stdout
,
3466 "Save segment, %lld bytes at 0x%s (%c%c%c)",
3467 size
, paddr_nz (addr
),
3469 write
? 'w' : ' ', exec
? 'x' : ' ');
3471 fprintf_filtered (gdb_stdout
, " for %s", filename
);
3472 fprintf_filtered (gdb_stdout
, "\n");
3475 /* Invoke the callback function to create the corefile
3477 func (addr
, size
, read
, write
, exec
, obfd
);
3479 do_cleanups (cleanup
);
3484 find_signalled_thread (struct thread_info
*info
, void *data
)
3486 if (info
->stop_signal
!= TARGET_SIGNAL_0
3487 && ptid_get_pid (info
->ptid
) == ptid_get_pid (inferior_ptid
))
3493 static enum target_signal
3494 find_stop_signal (void)
3496 struct thread_info
*info
=
3497 iterate_over_threads (find_signalled_thread
, NULL
);
3500 return info
->stop_signal
;
3502 return TARGET_SIGNAL_0
;
3505 /* Records the thread's register state for the corefile note
3509 linux_nat_do_thread_registers (bfd
*obfd
, ptid_t ptid
,
3510 char *note_data
, int *note_size
,
3511 enum target_signal stop_signal
)
3513 gdb_gregset_t gregs
;
3514 gdb_fpregset_t fpregs
;
3515 unsigned long lwp
= ptid_get_lwp (ptid
);
3516 struct regcache
*regcache
= get_thread_regcache (ptid
);
3517 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3518 const struct regset
*regset
;
3520 struct cleanup
*old_chain
;
3521 struct core_regset_section
*sect_list
;
3524 old_chain
= save_inferior_ptid ();
3525 inferior_ptid
= ptid
;
3526 target_fetch_registers (regcache
, -1);
3527 do_cleanups (old_chain
);
3529 core_regset_p
= gdbarch_regset_from_core_section_p (gdbarch
);
3530 sect_list
= gdbarch_core_regset_sections (gdbarch
);
3533 && (regset
= gdbarch_regset_from_core_section (gdbarch
, ".reg",
3534 sizeof (gregs
))) != NULL
3535 && regset
->collect_regset
!= NULL
)
3536 regset
->collect_regset (regset
, regcache
, -1,
3537 &gregs
, sizeof (gregs
));
3539 fill_gregset (regcache
, &gregs
, -1);
3541 note_data
= (char *) elfcore_write_prstatus (obfd
,
3545 stop_signal
, &gregs
);
3547 /* The loop below uses the new struct core_regset_section, which stores
3548 the supported section names and sizes for the core file. Note that
3549 note PRSTATUS needs to be treated specially. But the other notes are
3550 structurally the same, so they can benefit from the new struct. */
3551 if (core_regset_p
&& sect_list
!= NULL
)
3552 while (sect_list
->sect_name
!= NULL
)
3554 /* .reg was already handled above. */
3555 if (strcmp (sect_list
->sect_name
, ".reg") == 0)
3560 regset
= gdbarch_regset_from_core_section (gdbarch
,
3561 sect_list
->sect_name
,
3563 gdb_assert (regset
&& regset
->collect_regset
);
3564 gdb_regset
= xmalloc (sect_list
->size
);
3565 regset
->collect_regset (regset
, regcache
, -1,
3566 gdb_regset
, sect_list
->size
);
3567 note_data
= (char *) elfcore_write_register_note (obfd
,
3570 sect_list
->sect_name
,
3577 /* For architectures that does not have the struct core_regset_section
3578 implemented, we use the old method. When all the architectures have
3579 the new support, the code below should be deleted. */
3583 && (regset
= gdbarch_regset_from_core_section (gdbarch
, ".reg2",
3584 sizeof (fpregs
))) != NULL
3585 && regset
->collect_regset
!= NULL
)
3586 regset
->collect_regset (regset
, regcache
, -1,
3587 &fpregs
, sizeof (fpregs
));
3589 fill_fpregset (regcache
, &fpregs
, -1);
3591 note_data
= (char *) elfcore_write_prfpreg (obfd
,
3594 &fpregs
, sizeof (fpregs
));
3600 struct linux_nat_corefile_thread_data
3606 enum target_signal stop_signal
;
3609 /* Called by gdbthread.c once per thread. Records the thread's
3610 register state for the corefile note section. */
3613 linux_nat_corefile_thread_callback (struct lwp_info
*ti
, void *data
)
3615 struct linux_nat_corefile_thread_data
*args
= data
;
3617 args
->note_data
= linux_nat_do_thread_registers (args
->obfd
,
3627 /* Fills the "to_make_corefile_note" target vector. Builds the note
3628 section for a corefile, and returns it in a malloc buffer. */
3631 linux_nat_make_corefile_notes (bfd
*obfd
, int *note_size
)
3633 struct linux_nat_corefile_thread_data thread_args
;
3634 struct cleanup
*old_chain
;
3635 /* The variable size must be >= sizeof (prpsinfo_t.pr_fname). */
3636 char fname
[16] = { '\0' };
3637 /* The variable size must be >= sizeof (prpsinfo_t.pr_psargs). */
3638 char psargs
[80] = { '\0' };
3639 char *note_data
= NULL
;
3640 ptid_t current_ptid
= inferior_ptid
;
3641 ptid_t filter
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
3645 if (get_exec_file (0))
3647 strncpy (fname
, strrchr (get_exec_file (0), '/') + 1, sizeof (fname
));
3648 strncpy (psargs
, get_exec_file (0), sizeof (psargs
));
3649 if (get_inferior_args ())
3652 char *psargs_end
= psargs
+ sizeof (psargs
);
3654 /* linux_elfcore_write_prpsinfo () handles zero unterminated
3656 string_end
= memchr (psargs
, 0, sizeof (psargs
));
3657 if (string_end
!= NULL
)
3659 *string_end
++ = ' ';
3660 strncpy (string_end
, get_inferior_args (),
3661 psargs_end
- string_end
);
3664 note_data
= (char *) elfcore_write_prpsinfo (obfd
,
3666 note_size
, fname
, psargs
);
3669 /* Dump information for threads. */
3670 thread_args
.obfd
= obfd
;
3671 thread_args
.note_data
= note_data
;
3672 thread_args
.note_size
= note_size
;
3673 thread_args
.num_notes
= 0;
3674 thread_args
.stop_signal
= find_stop_signal ();
3675 iterate_over_lwps (filter
, linux_nat_corefile_thread_callback
, &thread_args
);
3676 gdb_assert (thread_args
.num_notes
!= 0);
3677 note_data
= thread_args
.note_data
;
3679 auxv_len
= target_read_alloc (¤t_target
, TARGET_OBJECT_AUXV
,
3683 note_data
= elfcore_write_note (obfd
, note_data
, note_size
,
3684 "CORE", NT_AUXV
, auxv
, auxv_len
);
3688 make_cleanup (xfree
, note_data
);
3692 /* Implement the "info proc" command. */
3695 linux_nat_info_proc_cmd (char *args
, int from_tty
)
3697 /* A long is used for pid instead of an int to avoid a loss of precision
3698 compiler warning from the output of strtoul. */
3699 long pid
= PIDGET (inferior_ptid
);
3702 char buffer
[MAXPATHLEN
];
3703 char fname1
[MAXPATHLEN
], fname2
[MAXPATHLEN
];
3716 /* Break up 'args' into an argv array. */
3717 argv
= gdb_buildargv (args
);
3718 make_cleanup_freeargv (argv
);
3720 while (argv
!= NULL
&& *argv
!= NULL
)
3722 if (isdigit (argv
[0][0]))
3724 pid
= strtoul (argv
[0], NULL
, 10);
3726 else if (strncmp (argv
[0], "mappings", strlen (argv
[0])) == 0)
3730 else if (strcmp (argv
[0], "status") == 0)
3734 else if (strcmp (argv
[0], "stat") == 0)
3738 else if (strcmp (argv
[0], "cmd") == 0)
3742 else if (strncmp (argv
[0], "exe", strlen (argv
[0])) == 0)
3746 else if (strcmp (argv
[0], "cwd") == 0)
3750 else if (strncmp (argv
[0], "all", strlen (argv
[0])) == 0)
3756 /* [...] (future options here) */
3761 error (_("No current process: you must name one."));
3763 sprintf (fname1
, "/proc/%ld", pid
);
3764 if (stat (fname1
, &dummy
) != 0)
3765 error (_("No /proc directory: '%s'"), fname1
);
3767 printf_filtered (_("process %ld\n"), pid
);
3768 if (cmdline_f
|| all
)
3770 sprintf (fname1
, "/proc/%ld/cmdline", pid
);
3771 if ((procfile
= fopen (fname1
, "r")) != NULL
)
3773 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
3774 if (fgets (buffer
, sizeof (buffer
), procfile
))
3775 printf_filtered ("cmdline = '%s'\n", buffer
);
3777 warning (_("unable to read '%s'"), fname1
);
3778 do_cleanups (cleanup
);
3781 warning (_("unable to open /proc file '%s'"), fname1
);
3785 sprintf (fname1
, "/proc/%ld/cwd", pid
);
3786 memset (fname2
, 0, sizeof (fname2
));
3787 if (readlink (fname1
, fname2
, sizeof (fname2
)) > 0)
3788 printf_filtered ("cwd = '%s'\n", fname2
);
3790 warning (_("unable to read link '%s'"), fname1
);
3794 sprintf (fname1
, "/proc/%ld/exe", pid
);
3795 memset (fname2
, 0, sizeof (fname2
));
3796 if (readlink (fname1
, fname2
, sizeof (fname2
)) > 0)
3797 printf_filtered ("exe = '%s'\n", fname2
);
3799 warning (_("unable to read link '%s'"), fname1
);
3801 if (mappings_f
|| all
)
3803 sprintf (fname1
, "/proc/%ld/maps", pid
);
3804 if ((procfile
= fopen (fname1
, "r")) != NULL
)
3806 long long addr
, endaddr
, size
, offset
, inode
;
3807 char permissions
[8], device
[8], filename
[MAXPATHLEN
];
3808 struct cleanup
*cleanup
;
3810 cleanup
= make_cleanup_fclose (procfile
);
3811 printf_filtered (_("Mapped address spaces:\n\n"));
3812 if (gdbarch_addr_bit (current_gdbarch
) == 32)
3814 printf_filtered ("\t%10s %10s %10s %10s %7s\n",
3817 " Size", " Offset", "objfile");
3821 printf_filtered (" %18s %18s %10s %10s %7s\n",
3824 " Size", " Offset", "objfile");
3827 while (read_mapping (procfile
, &addr
, &endaddr
, &permissions
[0],
3828 &offset
, &device
[0], &inode
, &filename
[0]))
3830 size
= endaddr
- addr
;
3832 /* FIXME: carlton/2003-08-27: Maybe the printf_filtered
3833 calls here (and possibly above) should be abstracted
3834 out into their own functions? Andrew suggests using
3835 a generic local_address_string instead to print out
3836 the addresses; that makes sense to me, too. */
3838 if (gdbarch_addr_bit (current_gdbarch
) == 32)
3840 printf_filtered ("\t%#10lx %#10lx %#10x %#10x %7s\n",
3841 (unsigned long) addr
, /* FIXME: pr_addr */
3842 (unsigned long) endaddr
,
3844 (unsigned int) offset
,
3845 filename
[0] ? filename
: "");
3849 printf_filtered (" %#18lx %#18lx %#10x %#10x %7s\n",
3850 (unsigned long) addr
, /* FIXME: pr_addr */
3851 (unsigned long) endaddr
,
3853 (unsigned int) offset
,
3854 filename
[0] ? filename
: "");
3858 do_cleanups (cleanup
);
3861 warning (_("unable to open /proc file '%s'"), fname1
);
3863 if (status_f
|| all
)
3865 sprintf (fname1
, "/proc/%ld/status", pid
);
3866 if ((procfile
= fopen (fname1
, "r")) != NULL
)
3868 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
3869 while (fgets (buffer
, sizeof (buffer
), procfile
) != NULL
)
3870 puts_filtered (buffer
);
3871 do_cleanups (cleanup
);
3874 warning (_("unable to open /proc file '%s'"), fname1
);
3878 sprintf (fname1
, "/proc/%ld/stat", pid
);
3879 if ((procfile
= fopen (fname1
, "r")) != NULL
)
3884 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
3886 if (fscanf (procfile
, "%d ", &itmp
) > 0)
3887 printf_filtered (_("Process: %d\n"), itmp
);
3888 if (fscanf (procfile
, "(%[^)]) ", &buffer
[0]) > 0)
3889 printf_filtered (_("Exec file: %s\n"), buffer
);
3890 if (fscanf (procfile
, "%c ", &ctmp
) > 0)
3891 printf_filtered (_("State: %c\n"), ctmp
);
3892 if (fscanf (procfile
, "%d ", &itmp
) > 0)
3893 printf_filtered (_("Parent process: %d\n"), itmp
);
3894 if (fscanf (procfile
, "%d ", &itmp
) > 0)
3895 printf_filtered (_("Process group: %d\n"), itmp
);
3896 if (fscanf (procfile
, "%d ", &itmp
) > 0)
3897 printf_filtered (_("Session id: %d\n"), itmp
);
3898 if (fscanf (procfile
, "%d ", &itmp
) > 0)
3899 printf_filtered (_("TTY: %d\n"), itmp
);
3900 if (fscanf (procfile
, "%d ", &itmp
) > 0)
3901 printf_filtered (_("TTY owner process group: %d\n"), itmp
);
3902 if (fscanf (procfile
, "%lu ", <mp
) > 0)
3903 printf_filtered (_("Flags: 0x%lx\n"), ltmp
);
3904 if (fscanf (procfile
, "%lu ", <mp
) > 0)
3905 printf_filtered (_("Minor faults (no memory page): %lu\n"),
3906 (unsigned long) ltmp
);
3907 if (fscanf (procfile
, "%lu ", <mp
) > 0)
3908 printf_filtered (_("Minor faults, children: %lu\n"),
3909 (unsigned long) ltmp
);
3910 if (fscanf (procfile
, "%lu ", <mp
) > 0)
3911 printf_filtered (_("Major faults (memory page faults): %lu\n"),
3912 (unsigned long) ltmp
);
3913 if (fscanf (procfile
, "%lu ", <mp
) > 0)
3914 printf_filtered (_("Major faults, children: %lu\n"),
3915 (unsigned long) ltmp
);
3916 if (fscanf (procfile
, "%ld ", <mp
) > 0)
3917 printf_filtered (_("utime: %ld\n"), ltmp
);
3918 if (fscanf (procfile
, "%ld ", <mp
) > 0)
3919 printf_filtered (_("stime: %ld\n"), ltmp
);
3920 if (fscanf (procfile
, "%ld ", <mp
) > 0)
3921 printf_filtered (_("utime, children: %ld\n"), ltmp
);
3922 if (fscanf (procfile
, "%ld ", <mp
) > 0)
3923 printf_filtered (_("stime, children: %ld\n"), ltmp
);
3924 if (fscanf (procfile
, "%ld ", <mp
) > 0)
3925 printf_filtered (_("jiffies remaining in current time slice: %ld\n"),
3927 if (fscanf (procfile
, "%ld ", <mp
) > 0)
3928 printf_filtered (_("'nice' value: %ld\n"), ltmp
);
3929 if (fscanf (procfile
, "%lu ", <mp
) > 0)
3930 printf_filtered (_("jiffies until next timeout: %lu\n"),
3931 (unsigned long) ltmp
);
3932 if (fscanf (procfile
, "%lu ", <mp
) > 0)
3933 printf_filtered (_("jiffies until next SIGALRM: %lu\n"),
3934 (unsigned long) ltmp
);
3935 if (fscanf (procfile
, "%ld ", <mp
) > 0)
3936 printf_filtered (_("start time (jiffies since system boot): %ld\n"),
3938 if (fscanf (procfile
, "%lu ", <mp
) > 0)
3939 printf_filtered (_("Virtual memory size: %lu\n"),
3940 (unsigned long) ltmp
);
3941 if (fscanf (procfile
, "%lu ", <mp
) > 0)
3942 printf_filtered (_("Resident set size: %lu\n"), (unsigned long) ltmp
);
3943 if (fscanf (procfile
, "%lu ", <mp
) > 0)
3944 printf_filtered (_("rlim: %lu\n"), (unsigned long) ltmp
);
3945 if (fscanf (procfile
, "%lu ", <mp
) > 0)
3946 printf_filtered (_("Start of text: 0x%lx\n"), ltmp
);
3947 if (fscanf (procfile
, "%lu ", <mp
) > 0)
3948 printf_filtered (_("End of text: 0x%lx\n"), ltmp
);
3949 if (fscanf (procfile
, "%lu ", <mp
) > 0)
3950 printf_filtered (_("Start of stack: 0x%lx\n"), ltmp
);
3951 #if 0 /* Don't know how architecture-dependent the rest is...
3952 Anyway the signal bitmap info is available from "status". */
3953 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
3954 printf_filtered (_("Kernel stack pointer: 0x%lx\n"), ltmp
);
3955 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
3956 printf_filtered (_("Kernel instr pointer: 0x%lx\n"), ltmp
);
3957 if (fscanf (procfile
, "%ld ", <mp
) > 0)
3958 printf_filtered (_("Pending signals bitmap: 0x%lx\n"), ltmp
);
3959 if (fscanf (procfile
, "%ld ", <mp
) > 0)
3960 printf_filtered (_("Blocked signals bitmap: 0x%lx\n"), ltmp
);
3961 if (fscanf (procfile
, "%ld ", <mp
) > 0)
3962 printf_filtered (_("Ignored signals bitmap: 0x%lx\n"), ltmp
);
3963 if (fscanf (procfile
, "%ld ", <mp
) > 0)
3964 printf_filtered (_("Catched signals bitmap: 0x%lx\n"), ltmp
);
3965 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
3966 printf_filtered (_("wchan (system call): 0x%lx\n"), ltmp
);
3968 do_cleanups (cleanup
);
3971 warning (_("unable to open /proc file '%s'"), fname1
);
3975 /* Implement the to_xfer_partial interface for memory reads using the /proc
3976 filesystem. Because we can use a single read() call for /proc, this
3977 can be much more efficient than banging away at PTRACE_PEEKTEXT,
3978 but it doesn't support writes. */
3981 linux_proc_xfer_partial (struct target_ops
*ops
, enum target_object object
,
3982 const char *annex
, gdb_byte
*readbuf
,
3983 const gdb_byte
*writebuf
,
3984 ULONGEST offset
, LONGEST len
)
3990 if (object
!= TARGET_OBJECT_MEMORY
|| !readbuf
)
3993 /* Don't bother for one word. */
3994 if (len
< 3 * sizeof (long))
3997 /* We could keep this file open and cache it - possibly one per
3998 thread. That requires some juggling, but is even faster. */
3999 sprintf (filename
, "/proc/%d/mem", PIDGET (inferior_ptid
));
4000 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4004 /* If pread64 is available, use it. It's faster if the kernel
4005 supports it (only one syscall), and it's 64-bit safe even on
4006 32-bit platforms (for instance, SPARC debugging a SPARC64
4009 if (pread64 (fd
, readbuf
, len
, offset
) != len
)
4011 if (lseek (fd
, offset
, SEEK_SET
) == -1 || read (fd
, readbuf
, len
) != len
)
4021 /* Parse LINE as a signal set and add its set bits to SIGS. */
4024 add_line_to_sigset (const char *line
, sigset_t
*sigs
)
4026 int len
= strlen (line
) - 1;
4030 if (line
[len
] != '\n')
4031 error (_("Could not parse signal set: %s"), line
);
4039 if (*p
>= '0' && *p
<= '9')
4041 else if (*p
>= 'a' && *p
<= 'f')
4042 digit
= *p
- 'a' + 10;
4044 error (_("Could not parse signal set: %s"), line
);
4049 sigaddset (sigs
, signum
+ 1);
4051 sigaddset (sigs
, signum
+ 2);
4053 sigaddset (sigs
, signum
+ 3);
4055 sigaddset (sigs
, signum
+ 4);
4061 /* Find process PID's pending signals from /proc/pid/status and set
4065 linux_proc_pending_signals (int pid
, sigset_t
*pending
, sigset_t
*blocked
, sigset_t
*ignored
)
4068 char buffer
[MAXPATHLEN
], fname
[MAXPATHLEN
];
4070 struct cleanup
*cleanup
;
4072 sigemptyset (pending
);
4073 sigemptyset (blocked
);
4074 sigemptyset (ignored
);
4075 sprintf (fname
, "/proc/%d/status", pid
);
4076 procfile
= fopen (fname
, "r");
4077 if (procfile
== NULL
)
4078 error (_("Could not open %s"), fname
);
4079 cleanup
= make_cleanup_fclose (procfile
);
4081 while (fgets (buffer
, MAXPATHLEN
, procfile
) != NULL
)
4083 /* Normal queued signals are on the SigPnd line in the status
4084 file. However, 2.6 kernels also have a "shared" pending
4085 queue for delivering signals to a thread group, so check for
4088 Unfortunately some Red Hat kernels include the shared pending
4089 queue but not the ShdPnd status field. */
4091 if (strncmp (buffer
, "SigPnd:\t", 8) == 0)
4092 add_line_to_sigset (buffer
+ 8, pending
);
4093 else if (strncmp (buffer
, "ShdPnd:\t", 8) == 0)
4094 add_line_to_sigset (buffer
+ 8, pending
);
4095 else if (strncmp (buffer
, "SigBlk:\t", 8) == 0)
4096 add_line_to_sigset (buffer
+ 8, blocked
);
4097 else if (strncmp (buffer
, "SigIgn:\t", 8) == 0)
4098 add_line_to_sigset (buffer
+ 8, ignored
);
4101 do_cleanups (cleanup
);
4105 linux_nat_xfer_osdata (struct target_ops
*ops
, enum target_object object
,
4106 const char *annex
, gdb_byte
*readbuf
,
4107 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
4109 /* We make the process list snapshot when the object starts to be
4111 static const char *buf
;
4112 static LONGEST len_avail
= -1;
4113 static struct obstack obstack
;
4117 gdb_assert (object
== TARGET_OBJECT_OSDATA
);
4119 if (strcmp (annex
, "processes") != 0)
4122 gdb_assert (readbuf
&& !writebuf
);
4126 if (len_avail
!= -1 && len_avail
!= 0)
4127 obstack_free (&obstack
, NULL
);
4130 obstack_init (&obstack
);
4131 obstack_grow_str (&obstack
, "<osdata type=\"processes\">\n");
4133 dirp
= opendir ("/proc");
4137 while ((dp
= readdir (dirp
)) != NULL
)
4139 struct stat statbuf
;
4140 char procentry
[sizeof ("/proc/4294967295")];
4142 if (!isdigit (dp
->d_name
[0])
4143 || NAMELEN (dp
) > sizeof ("4294967295") - 1)
4146 sprintf (procentry
, "/proc/%s", dp
->d_name
);
4147 if (stat (procentry
, &statbuf
) == 0
4148 && S_ISDIR (statbuf
.st_mode
))
4152 char cmd
[MAXPATHLEN
+ 1];
4153 struct passwd
*entry
;
4155 pathname
= xstrprintf ("/proc/%s/cmdline", dp
->d_name
);
4156 entry
= getpwuid (statbuf
.st_uid
);
4158 if ((f
= fopen (pathname
, "r")) != NULL
)
4160 size_t len
= fread (cmd
, 1, sizeof (cmd
) - 1, f
);
4164 for (i
= 0; i
< len
; i
++)
4169 obstack_xml_printf (
4172 "<column name=\"pid\">%s</column>"
4173 "<column name=\"user\">%s</column>"
4174 "<column name=\"command\">%s</column>"
4177 entry
? entry
->pw_name
: "?",
4190 obstack_grow_str0 (&obstack
, "</osdata>\n");
4191 buf
= obstack_finish (&obstack
);
4192 len_avail
= strlen (buf
);
4195 if (offset
>= len_avail
)
4197 /* Done. Get rid of the obstack. */
4198 obstack_free (&obstack
, NULL
);
4204 if (len
> len_avail
- offset
)
4205 len
= len_avail
- offset
;
4206 memcpy (readbuf
, buf
+ offset
, len
);
4212 linux_xfer_partial (struct target_ops
*ops
, enum target_object object
,
4213 const char *annex
, gdb_byte
*readbuf
,
4214 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
4218 if (object
== TARGET_OBJECT_AUXV
)
4219 return procfs_xfer_auxv (ops
, object
, annex
, readbuf
, writebuf
,
4222 if (object
== TARGET_OBJECT_OSDATA
)
4223 return linux_nat_xfer_osdata (ops
, object
, annex
, readbuf
, writebuf
,
4226 xfer
= linux_proc_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
4231 return super_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
4235 /* Create a prototype generic GNU/Linux target. The client can override
4236 it with local methods. */
4239 linux_target_install_ops (struct target_ops
*t
)
4241 t
->to_insert_fork_catchpoint
= linux_child_insert_fork_catchpoint
;
4242 t
->to_insert_vfork_catchpoint
= linux_child_insert_vfork_catchpoint
;
4243 t
->to_insert_exec_catchpoint
= linux_child_insert_exec_catchpoint
;
4244 t
->to_pid_to_exec_file
= linux_child_pid_to_exec_file
;
4245 t
->to_post_startup_inferior
= linux_child_post_startup_inferior
;
4246 t
->to_post_attach
= linux_child_post_attach
;
4247 t
->to_follow_fork
= linux_child_follow_fork
;
4248 t
->to_find_memory_regions
= linux_nat_find_memory_regions
;
4249 t
->to_make_corefile_notes
= linux_nat_make_corefile_notes
;
4251 super_xfer_partial
= t
->to_xfer_partial
;
4252 t
->to_xfer_partial
= linux_xfer_partial
;
4258 struct target_ops
*t
;
4260 t
= inf_ptrace_target ();
4261 linux_target_install_ops (t
);
4267 linux_trad_target (CORE_ADDR (*register_u_offset
)(struct gdbarch
*, int, int))
4269 struct target_ops
*t
;
4271 t
= inf_ptrace_trad_target (register_u_offset
);
4272 linux_target_install_ops (t
);
4277 /* target_is_async_p implementation. */
4280 linux_nat_is_async_p (void)
4282 /* NOTE: palves 2008-03-21: We're only async when the user requests
4283 it explicitly with the "set target-async" command.
4284 Someday, linux will always be async. */
4285 if (!target_async_permitted
)
4288 /* See target.h/target_async_mask. */
4289 return linux_nat_async_mask_value
;
4292 /* target_can_async_p implementation. */
4295 linux_nat_can_async_p (void)
4297 /* NOTE: palves 2008-03-21: We're only async when the user requests
4298 it explicitly with the "set target-async" command.
4299 Someday, linux will always be async. */
4300 if (!target_async_permitted
)
4303 /* See target.h/target_async_mask. */
4304 return linux_nat_async_mask_value
;
4308 linux_nat_supports_non_stop (void)
4313 /* True if we want to support multi-process. To be removed when GDB
4314 supports multi-exec. */
4316 int linux_multi_process
= 0;
4319 linux_nat_supports_multi_process (void)
4321 return linux_multi_process
;
4324 /* target_async_mask implementation. */
4327 linux_nat_async_mask (int new_mask
)
4329 int curr_mask
= linux_nat_async_mask_value
;
4331 if (curr_mask
!= new_mask
)
4335 linux_nat_async (NULL
, 0);
4336 linux_nat_async_mask_value
= new_mask
;
4340 linux_nat_async_mask_value
= new_mask
;
4342 /* If we're going out of async-mask in all-stop, then the
4343 inferior is stopped. The next resume will call
4344 target_async. In non-stop, the target event source
4345 should be always registered in the event loop. Do so
4348 linux_nat_async (inferior_event_handler
, 0);
4355 static int async_terminal_is_ours
= 1;
4357 /* target_terminal_inferior implementation. */
4360 linux_nat_terminal_inferior (void)
4362 if (!target_is_async_p ())
4364 /* Async mode is disabled. */
4365 terminal_inferior ();
4369 /* GDB should never give the terminal to the inferior, if the
4370 inferior is running in the background (run&, continue&, etc.).
4371 This check can be removed when the common code is fixed. */
4372 if (!sync_execution
)
4375 terminal_inferior ();
4377 if (!async_terminal_is_ours
)
4380 delete_file_handler (input_fd
);
4381 async_terminal_is_ours
= 0;
4385 /* target_terminal_ours implementation. */
4388 linux_nat_terminal_ours (void)
4390 if (!target_is_async_p ())
4392 /* Async mode is disabled. */
4397 /* GDB should never give the terminal to the inferior if the
4398 inferior is running in the background (run&, continue&, etc.),
4399 but claiming it sure should. */
4402 if (!sync_execution
)
4405 if (async_terminal_is_ours
)
4408 clear_sigint_trap ();
4409 add_file_handler (input_fd
, stdin_event_handler
, 0);
4410 async_terminal_is_ours
= 1;
4413 static void (*async_client_callback
) (enum inferior_event_type event_type
,
4415 static void *async_client_context
;
4417 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4418 so we notice when any child changes state, and notify the
4419 event-loop; it allows us to use sigsuspend in linux_nat_wait_1
4420 above to wait for the arrival of a SIGCHLD. */
4423 sigchld_handler (int signo
)
4425 int old_errno
= errno
;
4427 if (debug_linux_nat_async
)
4428 fprintf_unfiltered (gdb_stdlog
, "sigchld\n");
4430 if (signo
== SIGCHLD
4431 && linux_nat_event_pipe
[0] != -1)
4432 async_file_mark (); /* Let the event loop know that there are
4433 events to handle. */
4438 /* Callback registered with the target events file descriptor. */
4441 handle_target_event (int error
, gdb_client_data client_data
)
4443 (*async_client_callback
) (INF_REG_EVENT
, async_client_context
);
4446 /* Create/destroy the target events pipe. Returns previous state. */
4449 linux_async_pipe (int enable
)
4451 int previous
= (linux_nat_event_pipe
[0] != -1);
4453 if (previous
!= enable
)
4457 block_child_signals (&prev_mask
);
4461 if (pipe (linux_nat_event_pipe
) == -1)
4462 internal_error (__FILE__
, __LINE__
,
4463 "creating event pipe failed.");
4465 fcntl (linux_nat_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
4466 fcntl (linux_nat_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
4470 close (linux_nat_event_pipe
[0]);
4471 close (linux_nat_event_pipe
[1]);
4472 linux_nat_event_pipe
[0] = -1;
4473 linux_nat_event_pipe
[1] = -1;
4476 restore_child_signals_mask (&prev_mask
);
4482 /* target_async implementation. */
4485 linux_nat_async (void (*callback
) (enum inferior_event_type event_type
,
4486 void *context
), void *context
)
4488 if (linux_nat_async_mask_value
== 0 || !target_async_permitted
)
4489 internal_error (__FILE__
, __LINE__
,
4490 "Calling target_async when async is masked");
4492 if (callback
!= NULL
)
4494 async_client_callback
= callback
;
4495 async_client_context
= context
;
4496 if (!linux_async_pipe (1))
4498 add_file_handler (linux_nat_event_pipe
[0],
4499 handle_target_event
, NULL
);
4500 /* There may be pending events to handle. Tell the event loop
4507 async_client_callback
= callback
;
4508 async_client_context
= context
;
4509 delete_file_handler (linux_nat_event_pipe
[0]);
4510 linux_async_pipe (0);
4515 /* Stop an LWP, and push a TARGET_SIGNAL_0 stop status if no other
4519 linux_nat_stop_lwp (struct lwp_info
*lwp
, void *data
)
4524 ptid_t ptid
= lwp
->ptid
;
4526 if (debug_linux_nat
)
4527 fprintf_unfiltered (gdb_stdlog
,
4528 "LNSL: running -> suspending %s\n",
4529 target_pid_to_str (lwp
->ptid
));
4532 stop_callback (lwp
, NULL
);
4533 stop_wait_callback (lwp
, NULL
);
4535 /* If the lwp exits while we try to stop it, there's nothing
4537 lwp
= find_lwp_pid (ptid
);
4541 /* If we didn't collect any signal other than SIGSTOP while
4542 stopping the LWP, push a SIGNAL_0 event. In either case, the
4543 event-loop will end up calling target_wait which will collect
4545 if (lwp
->status
== 0)
4546 lwp
->status
= W_STOPCODE (0);
4551 /* Already known to be stopped; do nothing. */
4553 if (debug_linux_nat
)
4555 if (find_thread_pid (lwp
->ptid
)->stop_requested
)
4556 fprintf_unfiltered (gdb_stdlog
, "\
4557 LNSL: already stopped/stop_requested %s\n",
4558 target_pid_to_str (lwp
->ptid
));
4560 fprintf_unfiltered (gdb_stdlog
, "\
4561 LNSL: already stopped/no stop_requested yet %s\n",
4562 target_pid_to_str (lwp
->ptid
));
4569 linux_nat_stop (ptid_t ptid
)
4572 iterate_over_lwps (ptid
, linux_nat_stop_lwp
, NULL
);
4574 linux_ops
->to_stop (ptid
);
4578 linux_nat_close (int quitting
)
4580 /* Unregister from the event loop. */
4581 if (target_is_async_p ())
4582 target_async (NULL
, 0);
4584 /* Reset the async_masking. */
4585 linux_nat_async_mask_value
= 1;
4587 if (linux_ops
->to_close
)
4588 linux_ops
->to_close (quitting
);
4592 linux_nat_add_target (struct target_ops
*t
)
4594 /* Save the provided single-threaded target. We save this in a separate
4595 variable because another target we've inherited from (e.g. inf-ptrace)
4596 may have saved a pointer to T; we want to use it for the final
4597 process stratum target. */
4598 linux_ops_saved
= *t
;
4599 linux_ops
= &linux_ops_saved
;
4601 /* Override some methods for multithreading. */
4602 t
->to_create_inferior
= linux_nat_create_inferior
;
4603 t
->to_attach
= linux_nat_attach
;
4604 t
->to_detach
= linux_nat_detach
;
4605 t
->to_resume
= linux_nat_resume
;
4606 t
->to_wait
= linux_nat_wait
;
4607 t
->to_xfer_partial
= linux_nat_xfer_partial
;
4608 t
->to_kill
= linux_nat_kill
;
4609 t
->to_mourn_inferior
= linux_nat_mourn_inferior
;
4610 t
->to_thread_alive
= linux_nat_thread_alive
;
4611 t
->to_pid_to_str
= linux_nat_pid_to_str
;
4612 t
->to_has_thread_control
= tc_schedlock
;
4614 t
->to_can_async_p
= linux_nat_can_async_p
;
4615 t
->to_is_async_p
= linux_nat_is_async_p
;
4616 t
->to_supports_non_stop
= linux_nat_supports_non_stop
;
4617 t
->to_async
= linux_nat_async
;
4618 t
->to_async_mask
= linux_nat_async_mask
;
4619 t
->to_terminal_inferior
= linux_nat_terminal_inferior
;
4620 t
->to_terminal_ours
= linux_nat_terminal_ours
;
4621 t
->to_close
= linux_nat_close
;
4623 /* Methods for non-stop support. */
4624 t
->to_stop
= linux_nat_stop
;
4626 t
->to_supports_multi_process
= linux_nat_supports_multi_process
;
4628 /* We don't change the stratum; this target will sit at
4629 process_stratum and thread_db will set at thread_stratum. This
4630 is a little strange, since this is a multi-threaded-capable
4631 target, but we want to be on the stack below thread_db, and we
4632 also want to be used for single-threaded processes. */
4637 /* Register a method to call whenever a new thread is attached. */
4639 linux_nat_set_new_thread (struct target_ops
*t
, void (*new_thread
) (ptid_t
))
4641 /* Save the pointer. We only support a single registered instance
4642 of the GNU/Linux native target, so we do not need to map this to
4644 linux_nat_new_thread
= new_thread
;
4647 /* Register a method that converts a siginfo object between the layout
4648 that ptrace returns, and the layout in the architecture of the
4651 linux_nat_set_siginfo_fixup (struct target_ops
*t
,
4652 int (*siginfo_fixup
) (struct siginfo
*,
4656 /* Save the pointer. */
4657 linux_nat_siginfo_fixup
= siginfo_fixup
;
4660 /* Return the saved siginfo associated with PTID. */
4662 linux_nat_get_siginfo (ptid_t ptid
)
4664 struct lwp_info
*lp
= find_lwp_pid (ptid
);
4666 gdb_assert (lp
!= NULL
);
4668 return &lp
->siginfo
;
4671 /* Provide a prototype to silence -Wmissing-prototypes. */
4672 extern initialize_file_ftype _initialize_linux_nat
;
4675 _initialize_linux_nat (void)
4679 add_info ("proc", linux_nat_info_proc_cmd
, _("\
4680 Show /proc process information about any running process.\n\
4681 Specify any process id, or use the program being debugged by default.\n\
4682 Specify any of the following keywords for detailed info:\n\
4683 mappings -- list of mapped memory regions.\n\
4684 stat -- list a bunch of random process info.\n\
4685 status -- list a different bunch of random process info.\n\
4686 all -- list all available /proc info."));
4688 add_setshow_zinteger_cmd ("lin-lwp", class_maintenance
,
4689 &debug_linux_nat
, _("\
4690 Set debugging of GNU/Linux lwp module."), _("\
4691 Show debugging of GNU/Linux lwp module."), _("\
4692 Enables printf debugging output."),
4694 show_debug_linux_nat
,
4695 &setdebuglist
, &showdebuglist
);
4697 add_setshow_zinteger_cmd ("lin-lwp-async", class_maintenance
,
4698 &debug_linux_nat_async
, _("\
4699 Set debugging of GNU/Linux async lwp module."), _("\
4700 Show debugging of GNU/Linux async lwp module."), _("\
4701 Enables printf debugging output."),
4703 show_debug_linux_nat_async
,
4704 &setdebuglist
, &showdebuglist
);
4706 /* Save this mask as the default. */
4707 sigprocmask (SIG_SETMASK
, NULL
, &normal_mask
);
4709 /* Install a SIGCHLD handler. */
4710 sigchld_action
.sa_handler
= sigchld_handler
;
4711 sigemptyset (&sigchld_action
.sa_mask
);
4712 sigchld_action
.sa_flags
= SA_RESTART
;
4714 /* Make it the default. */
4715 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
4717 /* Make sure we don't block SIGCHLD during a sigsuspend. */
4718 sigprocmask (SIG_SETMASK
, NULL
, &suspend_mask
);
4719 sigdelset (&suspend_mask
, SIGCHLD
);
4721 sigemptyset (&blocked_mask
);
4723 add_setshow_boolean_cmd ("disable-randomization", class_support
,
4724 &disable_randomization
, _("\
4725 Set disabling of debuggee's virtual address space randomization."), _("\
4726 Show disabling of debuggee's virtual address space randomization."), _("\
4727 When this mode is on (which is the default), randomization of the virtual\n\
4728 address space is disabled. Standalone programs run with the randomization\n\
4729 enabled by default on some platforms."),
4730 &set_disable_randomization
,
4731 &show_disable_randomization
,
4732 &setlist
, &showlist
);
4736 /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to
4737 the GNU/Linux Threads library and therefore doesn't really belong
4740 /* Read variable NAME in the target and return its value if found.
4741 Otherwise return zero. It is assumed that the type of the variable
4745 get_signo (const char *name
)
4747 struct minimal_symbol
*ms
;
4750 ms
= lookup_minimal_symbol (name
, NULL
, NULL
);
4754 if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms
), (gdb_byte
*) &signo
,
4755 sizeof (signo
)) != 0)
4761 /* Return the set of signals used by the threads library in *SET. */
4764 lin_thread_get_thread_signals (sigset_t
*set
)
4766 struct sigaction action
;
4767 int restart
, cancel
;
4769 sigemptyset (&blocked_mask
);
4772 restart
= get_signo ("__pthread_sig_restart");
4773 cancel
= get_signo ("__pthread_sig_cancel");
4775 /* LinuxThreads normally uses the first two RT signals, but in some legacy
4776 cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does
4777 not provide any way for the debugger to query the signal numbers -
4778 fortunately they don't change! */
4781 restart
= __SIGRTMIN
;
4784 cancel
= __SIGRTMIN
+ 1;
4786 sigaddset (set
, restart
);
4787 sigaddset (set
, cancel
);
4789 /* The GNU/Linux Threads library makes terminating threads send a
4790 special "cancel" signal instead of SIGCHLD. Make sure we catch
4791 those (to prevent them from terminating GDB itself, which is
4792 likely to be their default action) and treat them the same way as
4795 action
.sa_handler
= sigchld_handler
;
4796 sigemptyset (&action
.sa_mask
);
4797 action
.sa_flags
= SA_RESTART
;
4798 sigaction (cancel
, &action
, NULL
);
4800 /* We block the "cancel" signal throughout this code ... */
4801 sigaddset (&blocked_mask
, cancel
);
4802 sigprocmask (SIG_BLOCK
, &blocked_mask
, NULL
);
4804 /* ... except during a sigsuspend. */
4805 sigdelset (&suspend_mask
, cancel
);