1 /* GNU/Linux native-dependent code common to multiple platforms.
3 Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
4 2011 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-ptrace.h"
34 #include "linux-fork.h"
35 #include "gdbthread.h"
39 #include "inf-ptrace.h"
41 #include <sys/param.h> /* for MAXPATHLEN */
42 #include <sys/procfs.h> /* for elf_gregset etc. */
43 #include "elf-bfd.h" /* for elfcore_write_* */
44 #include "gregset.h" /* for gregset */
45 #include "gdbcore.h" /* for get_exec_file */
46 #include <ctype.h> /* for isdigit */
47 #include "gdbthread.h" /* for struct thread_info etc. */
48 #include "gdb_stat.h" /* for struct stat */
49 #include <fcntl.h> /* for O_RDONLY */
51 #include "event-loop.h"
52 #include "event-top.h"
54 #include <sys/types.h>
55 #include "gdb_dirent.h"
56 #include "xml-support.h"
62 #define SPUFS_MAGIC 0x23c9b64e
65 #ifdef HAVE_PERSONALITY
66 # include <sys/personality.h>
67 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
68 # define ADDR_NO_RANDOMIZE 0x0040000
70 #endif /* HAVE_PERSONALITY */
72 /* This comment documents high-level logic of this file.
74 Waiting for events in sync mode
75 ===============================
77 When waiting for an event in a specific thread, we just use waitpid, passing
78 the specific pid, and not passing WNOHANG.
80 When waiting for an event in all threads, waitpid is not quite good. Prior to
81 version 2.4, Linux can either wait for event in main thread, or in secondary
82 threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might
83 miss an event. The solution is to use non-blocking waitpid, together with
84 sigsuspend. First, we use non-blocking waitpid to get an event in the main
85 process, if any. Second, we use non-blocking waitpid with the __WCLONED
86 flag to check for events in cloned processes. If nothing is found, we use
87 sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something
88 happened to a child process -- and SIGCHLD will be delivered both for events
89 in main debugged process and in cloned processes. As soon as we know there's
90 an event, we get back to calling nonblocking waitpid with and without
93 Note that SIGCHLD should be blocked between waitpid and sigsuspend calls,
94 so that we don't miss a signal. If SIGCHLD arrives in between, when it's
95 blocked, the signal becomes pending and sigsuspend immediately
96 notices it and returns.
98 Waiting for events in async mode
99 ================================
101 In async mode, GDB should always be ready to handle both user input
102 and target events, so neither blocking waitpid nor sigsuspend are
103 viable options. Instead, we should asynchronously notify the GDB main
104 event loop whenever there's an unprocessed event from the target. We
105 detect asynchronous target events by handling SIGCHLD signals. To
106 notify the event loop about target events, the self-pipe trick is used
107 --- a pipe is registered as waitable event source in the event loop,
108 the event loop select/poll's on the read end of this pipe (as well on
109 other event sources, e.g., stdin), and the SIGCHLD handler writes a
110 byte to this pipe. This is more portable than relying on
111 pselect/ppoll, since on kernels that lack those syscalls, libc
112 emulates them with select/poll+sigprocmask, and that is racy
113 (a.k.a. plain broken).
115 Obviously, if we fail to notify the event loop if there's a target
116 event, it's bad. OTOH, if we notify the event loop when there's no
117 event from the target, linux_nat_wait will detect that there's no real
118 event to report, and return event of type TARGET_WAITKIND_IGNORE.
119 This is mostly harmless, but it will waste time and is better avoided.
121 The main design point is that every time GDB is outside linux-nat.c,
122 we have a SIGCHLD handler installed that is called when something
123 happens to the target and notifies the GDB event loop. Whenever GDB
124 core decides to handle the event, and calls into linux-nat.c, we
125 process things as in sync mode, except that the we never block in
128 While processing an event, we may end up momentarily blocked in
129 waitpid calls. Those waitpid calls, while blocking, are guarantied to
130 return quickly. E.g., in all-stop mode, before reporting to the core
131 that an LWP hit a breakpoint, all LWPs are stopped by sending them
132 SIGSTOP, and synchronously waiting for the SIGSTOP to be reported.
133 Note that this is different from blocking indefinitely waiting for the
134 next event --- here, we're already handling an event.
139 We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another
140 signal is not entirely significant; we just need for a signal to be delivered,
141 so that we can intercept it. SIGSTOP's advantage is that it can not be
142 blocked. A disadvantage is that it is not a real-time signal, so it can only
143 be queued once; we do not keep track of other sources of SIGSTOP.
145 Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't
146 use them, because they have special behavior when the signal is generated -
147 not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL
148 kills the entire thread group.
150 A delivered SIGSTOP would stop the entire thread group, not just the thread we
151 tkill'd. But we never let the SIGSTOP be delivered; we always intercept and
152 cancel it (by PTRACE_CONT without passing SIGSTOP).
154 We could use a real-time signal instead. This would solve those problems; we
155 could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB.
156 But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH
157 generates it, and there are races with trying to find a signal that is not
161 #define O_LARGEFILE 0
164 /* Unlike other extended result codes, WSTOPSIG (status) on
165 PTRACE_O_TRACESYSGOOD syscall events doesn't return SIGTRAP, but
166 instead SIGTRAP with bit 7 set. */
167 #define SYSCALL_SIGTRAP (SIGTRAP | 0x80)
169 /* The single-threaded native GNU/Linux target_ops. We save a pointer for
170 the use of the multi-threaded target. */
171 static struct target_ops *linux_ops;
172 static struct target_ops linux_ops_saved;
174 /* The method to call, if any, when a new thread is attached. */
175 static void (*linux_nat_new_thread) (ptid_t);
177 /* The method to call, if any, when the siginfo object needs to be
178 converted between the layout returned by ptrace, and the layout in
179 the architecture of the inferior. */
180 static int (*linux_nat_siginfo_fixup) (struct siginfo *,
184 /* The saved to_xfer_partial method, inherited from inf-ptrace.c.
185 Called by our to_xfer_partial. */
186 static LONGEST (*super_xfer_partial) (struct target_ops *,
188 const char *, gdb_byte *,
192 static int debug_linux_nat;
194 show_debug_linux_nat (struct ui_file *file, int from_tty,
195 struct cmd_list_element *c, const char *value)
197 fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"),
201 static int disable_randomization = 1;
204 show_disable_randomization (struct ui_file *file, int from_tty,
205 struct cmd_list_element *c, const char *value)
207 #ifdef HAVE_PERSONALITY
208 fprintf_filtered (file,
209 _("Disabling randomization of debuggee's "
210 "virtual address space is %s.\n"),
212 #else /* !HAVE_PERSONALITY */
213 fputs_filtered (_("Disabling randomization of debuggee's "
214 "virtual address space is unsupported on\n"
215 "this platform.\n"), file);
216 #endif /* !HAVE_PERSONALITY */
220 set_disable_randomization (char *args, int from_tty,
221 struct cmd_list_element *c)
223 #ifndef HAVE_PERSONALITY
224 error (_("Disabling randomization of debuggee's "
225 "virtual address space is unsupported on\n"
227 #endif /* !HAVE_PERSONALITY */
230 struct simple_pid_list
234 struct simple_pid_list *next;
236 struct simple_pid_list *stopped_pids;
238 /* This variable is a tri-state flag: -1 for unknown, 0 if PTRACE_O_TRACEFORK
239 can not be used, 1 if it can. */
241 static int linux_supports_tracefork_flag = -1;
243 /* This variable is a tri-state flag: -1 for unknown, 0 if
244 PTRACE_O_TRACESYSGOOD can not be used, 1 if it can. */
246 static int linux_supports_tracesysgood_flag = -1;
248 /* If we have PTRACE_O_TRACEFORK, this flag indicates whether we also have
249 PTRACE_O_TRACEVFORKDONE. */
251 static int linux_supports_tracevforkdone_flag = -1;
253 /* Stores the current used ptrace() options. */
254 static int current_ptrace_options = 0;
256 /* Async mode support. */
258 /* The read/write ends of the pipe registered as waitable file in the
260 static int linux_nat_event_pipe[2] = { -1, -1 };
262 /* Flush the event pipe. */
265 async_file_flush (void)
272 ret = read (linux_nat_event_pipe[0], &buf, 1);
274 while (ret >= 0 || (ret == -1 && errno == EINTR));
277 /* Put something (anything, doesn't matter what, or how much) in event
278 pipe, so that the select/poll in the event-loop realizes we have
279 something to process. */
282 async_file_mark (void)
286 /* It doesn't really matter what the pipe contains, as long we end
287 up with something in it. Might as well flush the previous
293 ret = write (linux_nat_event_pipe[1], "+", 1);
295 while (ret == -1 && errno == EINTR);
297 /* Ignore EAGAIN. If the pipe is full, the event loop will already
298 be awakened anyway. */
301 static void linux_nat_async (void (*callback)
302 (enum inferior_event_type event_type,
305 static int kill_lwp (int lwpid, int signo);
307 static int stop_callback (struct lwp_info *lp, void *data);
309 static void block_child_signals (sigset_t *prev_mask);
310 static void restore_child_signals_mask (sigset_t *prev_mask);
313 static struct lwp_info *add_lwp (ptid_t ptid);
314 static void purge_lwp_list (int pid);
315 static struct lwp_info *find_lwp_pid (ptid_t ptid);
318 /* Trivial list manipulation functions to keep track of a list of
319 new stopped processes. */
321 add_to_pid_list (struct simple_pid_list **listp, int pid, int status)
323 struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list));
326 new_pid->status = status;
327 new_pid->next = *listp;
332 pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp)
334 struct simple_pid_list **p;
336 for (p = listp; *p != NULL; p = &(*p)->next)
337 if ((*p)->pid == pid)
339 struct simple_pid_list *next = (*p)->next;
341 *statusp = (*p)->status;
350 linux_record_stopped_pid (int pid, int status)
352 add_to_pid_list (&stopped_pids, pid, status);
356 /* A helper function for linux_test_for_tracefork, called after fork (). */
359 linux_tracefork_child (void)
361 ptrace (PTRACE_TRACEME, 0, 0, 0);
362 kill (getpid (), SIGSTOP);
367 /* Wrapper function for waitpid which handles EINTR. */
370 my_waitpid (int pid, int *statusp, int flags)
376 ret = waitpid (pid, statusp, flags);
378 while (ret == -1 && errno == EINTR);
383 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events.
385 First, we try to enable fork tracing on ORIGINAL_PID. If this fails,
386 we know that the feature is not available. This may change the tracing
387 options for ORIGINAL_PID, but we'll be setting them shortly anyway.
389 However, if it succeeds, we don't know for sure that the feature is
390 available; old versions of PTRACE_SETOPTIONS ignored unknown options. We
391 create a child process, attach to it, use PTRACE_SETOPTIONS to enable
392 fork tracing, and let it fork. If the process exits, we assume that we
393 can't use TRACEFORK; if we get the fork notification, and we can extract
394 the new child's PID, then we assume that we can. */
397 linux_test_for_tracefork (int original_pid)
399 int child_pid, ret, status;
403 /* We don't want those ptrace calls to be interrupted. */
404 block_child_signals (&prev_mask);
406 linux_supports_tracefork_flag = 0;
407 linux_supports_tracevforkdone_flag = 0;
409 ret = ptrace (PTRACE_SETOPTIONS, original_pid, 0, PTRACE_O_TRACEFORK);
412 restore_child_signals_mask (&prev_mask);
418 perror_with_name (("fork"));
421 linux_tracefork_child ();
423 ret = my_waitpid (child_pid, &status, 0);
425 perror_with_name (("waitpid"));
426 else if (ret != child_pid)
427 error (_("linux_test_for_tracefork: waitpid: unexpected result %d."), ret);
428 if (! WIFSTOPPED (status))
429 error (_("linux_test_for_tracefork: waitpid: unexpected status %d."),
432 ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0, PTRACE_O_TRACEFORK);
435 ret = ptrace (PTRACE_KILL, child_pid, 0, 0);
438 warning (_("linux_test_for_tracefork: failed to kill child"));
439 restore_child_signals_mask (&prev_mask);
443 ret = my_waitpid (child_pid, &status, 0);
444 if (ret != child_pid)
445 warning (_("linux_test_for_tracefork: failed "
446 "to wait for killed child"));
447 else if (!WIFSIGNALED (status))
448 warning (_("linux_test_for_tracefork: unexpected "
449 "wait status 0x%x from killed child"), status);
451 restore_child_signals_mask (&prev_mask);
455 /* Check whether PTRACE_O_TRACEVFORKDONE is available. */
456 ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0,
457 PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORKDONE);
458 linux_supports_tracevforkdone_flag = (ret == 0);
460 ret = ptrace (PTRACE_CONT, child_pid, 0, 0);
462 warning (_("linux_test_for_tracefork: failed to resume child"));
464 ret = my_waitpid (child_pid, &status, 0);
466 if (ret == child_pid && WIFSTOPPED (status)
467 && status >> 16 == PTRACE_EVENT_FORK)
470 ret = ptrace (PTRACE_GETEVENTMSG, child_pid, 0, &second_pid);
471 if (ret == 0 && second_pid != 0)
475 linux_supports_tracefork_flag = 1;
476 my_waitpid (second_pid, &second_status, 0);
477 ret = ptrace (PTRACE_KILL, second_pid, 0, 0);
479 warning (_("linux_test_for_tracefork: "
480 "failed to kill second child"));
481 my_waitpid (second_pid, &status, 0);
485 warning (_("linux_test_for_tracefork: unexpected result from waitpid "
486 "(%d, status 0x%x)"), ret, status);
488 ret = ptrace (PTRACE_KILL, child_pid, 0, 0);
490 warning (_("linux_test_for_tracefork: failed to kill child"));
491 my_waitpid (child_pid, &status, 0);
493 restore_child_signals_mask (&prev_mask);
496 /* Determine if PTRACE_O_TRACESYSGOOD can be used to follow syscalls.
498 We try to enable syscall tracing on ORIGINAL_PID. If this fails,
499 we know that the feature is not available. This may change the tracing
500 options for ORIGINAL_PID, but we'll be setting them shortly anyway. */
503 linux_test_for_tracesysgood (int original_pid)
508 /* We don't want those ptrace calls to be interrupted. */
509 block_child_signals (&prev_mask);
511 linux_supports_tracesysgood_flag = 0;
513 ret = ptrace (PTRACE_SETOPTIONS, original_pid, 0, PTRACE_O_TRACESYSGOOD);
517 linux_supports_tracesysgood_flag = 1;
519 restore_child_signals_mask (&prev_mask);
522 /* Determine wether we support PTRACE_O_TRACESYSGOOD option available.
523 This function also sets linux_supports_tracesysgood_flag. */
526 linux_supports_tracesysgood (int pid)
528 if (linux_supports_tracesysgood_flag == -1)
529 linux_test_for_tracesysgood (pid);
530 return linux_supports_tracesysgood_flag;
533 /* Return non-zero iff we have tracefork functionality available.
534 This function also sets linux_supports_tracefork_flag. */
537 linux_supports_tracefork (int pid)
539 if (linux_supports_tracefork_flag == -1)
540 linux_test_for_tracefork (pid);
541 return linux_supports_tracefork_flag;
545 linux_supports_tracevforkdone (int pid)
547 if (linux_supports_tracefork_flag == -1)
548 linux_test_for_tracefork (pid);
549 return linux_supports_tracevforkdone_flag;
553 linux_enable_tracesysgood (ptid_t ptid)
555 int pid = ptid_get_lwp (ptid);
558 pid = ptid_get_pid (ptid);
560 if (linux_supports_tracesysgood (pid) == 0)
563 current_ptrace_options |= PTRACE_O_TRACESYSGOOD;
565 ptrace (PTRACE_SETOPTIONS, pid, 0, current_ptrace_options);
570 linux_enable_event_reporting (ptid_t ptid)
572 int pid = ptid_get_lwp (ptid);
575 pid = ptid_get_pid (ptid);
577 if (! linux_supports_tracefork (pid))
580 current_ptrace_options |= PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK
581 | PTRACE_O_TRACEEXEC | PTRACE_O_TRACECLONE;
583 if (linux_supports_tracevforkdone (pid))
584 current_ptrace_options |= PTRACE_O_TRACEVFORKDONE;
586 /* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to support
587 read-only process state. */
589 ptrace (PTRACE_SETOPTIONS, pid, 0, current_ptrace_options);
593 linux_child_post_attach (int pid)
595 linux_enable_event_reporting (pid_to_ptid (pid));
596 check_for_thread_db ();
597 linux_enable_tracesysgood (pid_to_ptid (pid));
601 linux_child_post_startup_inferior (ptid_t ptid)
603 linux_enable_event_reporting (ptid);
604 check_for_thread_db ();
605 linux_enable_tracesysgood (ptid);
609 linux_child_follow_fork (struct target_ops *ops, int follow_child)
613 int parent_pid, child_pid;
615 block_child_signals (&prev_mask);
617 has_vforked = (inferior_thread ()->pending_follow.kind
618 == TARGET_WAITKIND_VFORKED);
619 parent_pid = ptid_get_lwp (inferior_ptid);
621 parent_pid = ptid_get_pid (inferior_ptid);
622 child_pid = PIDGET (inferior_thread ()->pending_follow.value.related_pid);
625 linux_enable_event_reporting (pid_to_ptid (child_pid));
628 && !non_stop /* Non-stop always resumes both branches. */
629 && (!target_is_async_p () || sync_execution)
630 && !(follow_child || detach_fork || sched_multi))
632 /* The parent stays blocked inside the vfork syscall until the
633 child execs or exits. If we don't let the child run, then
634 the parent stays blocked. If we're telling the parent to run
635 in the foreground, the user will not be able to ctrl-c to get
636 back the terminal, effectively hanging the debug session. */
637 fprintf_filtered (gdb_stderr, _("\
638 Can not resume the parent process over vfork in the foreground while\n\
639 holding the child stopped. Try \"set detach-on-fork\" or \
640 \"set schedule-multiple\".\n"));
641 /* FIXME output string > 80 columns. */
647 struct lwp_info *child_lp = NULL;
649 /* We're already attached to the parent, by default. */
651 /* Detach new forked process? */
654 /* Before detaching from the child, remove all breakpoints
655 from it. If we forked, then this has already been taken
656 care of by infrun.c. If we vforked however, any
657 breakpoint inserted in the parent is visible in the
658 child, even those added while stopped in a vfork
659 catchpoint. This will remove the breakpoints from the
660 parent also, but they'll be reinserted below. */
663 /* keep breakpoints list in sync. */
664 remove_breakpoints_pid (GET_PID (inferior_ptid));
667 if (info_verbose || debug_linux_nat)
669 target_terminal_ours ();
670 fprintf_filtered (gdb_stdlog,
671 "Detaching after fork from "
672 "child process %d.\n",
676 ptrace (PTRACE_DETACH, child_pid, 0, 0);
680 struct inferior *parent_inf, *child_inf;
681 struct cleanup *old_chain;
683 /* Add process to GDB's tables. */
684 child_inf = add_inferior (child_pid);
686 parent_inf = current_inferior ();
687 child_inf->attach_flag = parent_inf->attach_flag;
688 copy_terminal_info (child_inf, parent_inf);
690 old_chain = save_inferior_ptid ();
691 save_current_program_space ();
693 inferior_ptid = ptid_build (child_pid, child_pid, 0);
694 add_thread (inferior_ptid);
695 child_lp = add_lwp (inferior_ptid);
696 child_lp->stopped = 1;
697 child_lp->resumed = 1;
699 /* If this is a vfork child, then the address-space is
700 shared with the parent. */
703 child_inf->pspace = parent_inf->pspace;
704 child_inf->aspace = parent_inf->aspace;
706 /* The parent will be frozen until the child is done
707 with the shared region. Keep track of the
709 child_inf->vfork_parent = parent_inf;
710 child_inf->pending_detach = 0;
711 parent_inf->vfork_child = child_inf;
712 parent_inf->pending_detach = 0;
716 child_inf->aspace = new_address_space ();
717 child_inf->pspace = add_program_space (child_inf->aspace);
718 child_inf->removable = 1;
719 set_current_program_space (child_inf->pspace);
720 clone_program_space (child_inf->pspace, parent_inf->pspace);
722 /* Let the shared library layer (solib-svr4) learn about
723 this new process, relocate the cloned exec, pull in
724 shared libraries, and install the solib event
725 breakpoint. If a "cloned-VM" event was propagated
726 better throughout the core, this wouldn't be
728 solib_create_inferior_hook (0);
731 /* Let the thread_db layer learn about this new process. */
732 check_for_thread_db ();
734 do_cleanups (old_chain);
740 struct inferior *parent_inf;
742 parent_inf = current_inferior ();
744 /* If we detached from the child, then we have to be careful
745 to not insert breakpoints in the parent until the child
746 is done with the shared memory region. However, if we're
747 staying attached to the child, then we can and should
748 insert breakpoints, so that we can debug it. A
749 subsequent child exec or exit is enough to know when does
750 the child stops using the parent's address space. */
751 parent_inf->waiting_for_vfork_done = detach_fork;
752 parent_inf->pspace->breakpoints_not_allowed = detach_fork;
754 lp = find_lwp_pid (pid_to_ptid (parent_pid));
755 gdb_assert (linux_supports_tracefork_flag >= 0);
756 if (linux_supports_tracevforkdone (0))
759 fprintf_unfiltered (gdb_stdlog,
760 "LCFF: waiting for VFORK_DONE on %d\n",
766 /* We'll handle the VFORK_DONE event like any other
767 event, in target_wait. */
771 /* We can't insert breakpoints until the child has
772 finished with the shared memory region. We need to
773 wait until that happens. Ideal would be to just
775 - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0);
776 - waitpid (parent_pid, &status, __WALL);
777 However, most architectures can't handle a syscall
778 being traced on the way out if it wasn't traced on
781 We might also think to loop, continuing the child
782 until it exits or gets a SIGTRAP. One problem is
783 that the child might call ptrace with PTRACE_TRACEME.
785 There's no simple and reliable way to figure out when
786 the vforked child will be done with its copy of the
787 shared memory. We could step it out of the syscall,
788 two instructions, let it go, and then single-step the
789 parent once. When we have hardware single-step, this
790 would work; with software single-step it could still
791 be made to work but we'd have to be able to insert
792 single-step breakpoints in the child, and we'd have
793 to insert -just- the single-step breakpoint in the
794 parent. Very awkward.
796 In the end, the best we can do is to make sure it
797 runs for a little while. Hopefully it will be out of
798 range of any breakpoints we reinsert. Usually this
799 is only the single-step breakpoint at vfork's return
803 fprintf_unfiltered (gdb_stdlog,
804 "LCFF: no VFORK_DONE "
805 "support, sleeping a bit\n");
809 /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event,
810 and leave it pending. The next linux_nat_resume call
811 will notice a pending event, and bypasses actually
812 resuming the inferior. */
814 lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE;
818 /* If we're in async mode, need to tell the event loop
819 there's something here to process. */
820 if (target_can_async_p ())
827 struct inferior *parent_inf, *child_inf;
829 struct program_space *parent_pspace;
831 if (info_verbose || debug_linux_nat)
833 target_terminal_ours ();
835 fprintf_filtered (gdb_stdlog,
836 _("Attaching after process %d "
837 "vfork to child process %d.\n"),
838 parent_pid, child_pid);
840 fprintf_filtered (gdb_stdlog,
841 _("Attaching after process %d "
842 "fork to child process %d.\n"),
843 parent_pid, child_pid);
846 /* Add the new inferior first, so that the target_detach below
847 doesn't unpush the target. */
849 child_inf = add_inferior (child_pid);
851 parent_inf = current_inferior ();
852 child_inf->attach_flag = parent_inf->attach_flag;
853 copy_terminal_info (child_inf, parent_inf);
855 parent_pspace = parent_inf->pspace;
857 /* If we're vforking, we want to hold on to the parent until the
858 child exits or execs. At child exec or exit time we can
859 remove the old breakpoints from the parent and detach or
860 resume debugging it. Otherwise, detach the parent now; we'll
861 want to reuse it's program/address spaces, but we can't set
862 them to the child before removing breakpoints from the
863 parent, otherwise, the breakpoints module could decide to
864 remove breakpoints from the wrong process (since they'd be
865 assigned to the same address space). */
869 gdb_assert (child_inf->vfork_parent == NULL);
870 gdb_assert (parent_inf->vfork_child == NULL);
871 child_inf->vfork_parent = parent_inf;
872 child_inf->pending_detach = 0;
873 parent_inf->vfork_child = child_inf;
874 parent_inf->pending_detach = detach_fork;
875 parent_inf->waiting_for_vfork_done = 0;
877 else if (detach_fork)
878 target_detach (NULL, 0);
880 /* Note that the detach above makes PARENT_INF dangling. */
882 /* Add the child thread to the appropriate lists, and switch to
883 this new thread, before cloning the program space, and
884 informing the solib layer about this new process. */
886 inferior_ptid = ptid_build (child_pid, child_pid, 0);
887 add_thread (inferior_ptid);
888 lp = add_lwp (inferior_ptid);
892 /* If this is a vfork child, then the address-space is shared
893 with the parent. If we detached from the parent, then we can
894 reuse the parent's program/address spaces. */
895 if (has_vforked || detach_fork)
897 child_inf->pspace = parent_pspace;
898 child_inf->aspace = child_inf->pspace->aspace;
902 child_inf->aspace = new_address_space ();
903 child_inf->pspace = add_program_space (child_inf->aspace);
904 child_inf->removable = 1;
905 set_current_program_space (child_inf->pspace);
906 clone_program_space (child_inf->pspace, parent_pspace);
908 /* Let the shared library layer (solib-svr4) learn about
909 this new process, relocate the cloned exec, pull in
910 shared libraries, and install the solib event breakpoint.
911 If a "cloned-VM" event was propagated better throughout
912 the core, this wouldn't be required. */
913 solib_create_inferior_hook (0);
916 /* Let the thread_db layer learn about this new process. */
917 check_for_thread_db ();
920 restore_child_signals_mask (&prev_mask);
926 linux_child_insert_fork_catchpoint (int pid)
928 return !linux_supports_tracefork (pid);
932 linux_child_remove_fork_catchpoint (int pid)
938 linux_child_insert_vfork_catchpoint (int pid)
940 return !linux_supports_tracefork (pid);
944 linux_child_remove_vfork_catchpoint (int pid)
950 linux_child_insert_exec_catchpoint (int pid)
952 return !linux_supports_tracefork (pid);
956 linux_child_remove_exec_catchpoint (int pid)
962 linux_child_set_syscall_catchpoint (int pid, int needed, int any_count,
963 int table_size, int *table)
965 if (!linux_supports_tracesysgood (pid))
968 /* On GNU/Linux, we ignore the arguments. It means that we only
969 enable the syscall catchpoints, but do not disable them.
971 Also, we do not use the `table' information because we do not
972 filter system calls here. We let GDB do the logic for us. */
976 /* On GNU/Linux there are no real LWP's. The closest thing to LWP's
977 are processes sharing the same VM space. A multi-threaded process
978 is basically a group of such processes. However, such a grouping
979 is almost entirely a user-space issue; the kernel doesn't enforce
980 such a grouping at all (this might change in the future). In
981 general, we'll rely on the threads library (i.e. the GNU/Linux
982 Threads library) to provide such a grouping.
984 It is perfectly well possible to write a multi-threaded application
985 without the assistance of a threads library, by using the clone
986 system call directly. This module should be able to give some
987 rudimentary support for debugging such applications if developers
988 specify the CLONE_PTRACE flag in the clone system call, and are
989 using the Linux kernel 2.4 or above.
991 Note that there are some peculiarities in GNU/Linux that affect
994 - In general one should specify the __WCLONE flag to waitpid in
995 order to make it report events for any of the cloned processes
996 (and leave it out for the initial process). However, if a cloned
997 process has exited the exit status is only reported if the
998 __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but
999 we cannot use it since GDB must work on older systems too.
1001 - When a traced, cloned process exits and is waited for by the
1002 debugger, the kernel reassigns it to the original parent and
1003 keeps it around as a "zombie". Somehow, the GNU/Linux Threads
1004 library doesn't notice this, which leads to the "zombie problem":
1005 When debugged a multi-threaded process that spawns a lot of
1006 threads will run out of processes, even if the threads exit,
1007 because the "zombies" stay around. */
1009 /* List of known LWPs. */
1010 struct lwp_info *lwp_list;
1013 /* Original signal mask. */
1014 static sigset_t normal_mask;
1016 /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in
1017 _initialize_linux_nat. */
1018 static sigset_t suspend_mask;
1020 /* Signals to block to make that sigsuspend work. */
1021 static sigset_t blocked_mask;
1023 /* SIGCHLD action. */
1024 struct sigaction sigchld_action;
1026 /* Block child signals (SIGCHLD and linux threads signals), and store
1027 the previous mask in PREV_MASK. */
1030 block_child_signals (sigset_t *prev_mask)
1032 /* Make sure SIGCHLD is blocked. */
1033 if (!sigismember (&blocked_mask, SIGCHLD))
1034 sigaddset (&blocked_mask, SIGCHLD);
1036 sigprocmask (SIG_BLOCK, &blocked_mask, prev_mask);
1039 /* Restore child signals mask, previously returned by
1040 block_child_signals. */
1043 restore_child_signals_mask (sigset_t *prev_mask)
1045 sigprocmask (SIG_SETMASK, prev_mask, NULL);
1048 /* Mask of signals to pass directly to the inferior. */
1049 static sigset_t pass_mask;
1051 /* Update signals to pass to the inferior. */
1053 linux_nat_pass_signals (int numsigs, unsigned char *pass_signals)
1057 sigemptyset (&pass_mask);
1059 for (signo = 1; signo < NSIG; signo++)
1061 int target_signo = target_signal_from_host (signo);
1062 if (target_signo < numsigs && pass_signals[target_signo])
1063 sigaddset (&pass_mask, signo);
1069 /* Prototypes for local functions. */
1070 static int stop_wait_callback (struct lwp_info *lp, void *data);
1071 static int linux_thread_alive (ptid_t ptid);
1072 static char *linux_child_pid_to_exec_file (int pid);
1075 /* Convert wait status STATUS to a string. Used for printing debug
1079 status_to_str (int status)
1081 static char buf[64];
1083 if (WIFSTOPPED (status))
1085 if (WSTOPSIG (status) == SYSCALL_SIGTRAP)
1086 snprintf (buf, sizeof (buf), "%s (stopped at syscall)",
1087 strsignal (SIGTRAP));
1089 snprintf (buf, sizeof (buf), "%s (stopped)",
1090 strsignal (WSTOPSIG (status)));
1092 else if (WIFSIGNALED (status))
1093 snprintf (buf, sizeof (buf), "%s (terminated)",
1094 strsignal (WTERMSIG (status)));
1096 snprintf (buf, sizeof (buf), "%d (exited)", WEXITSTATUS (status));
1101 /* Remove all LWPs belong to PID from the lwp list. */
1104 purge_lwp_list (int pid)
1106 struct lwp_info *lp, *lpprev, *lpnext;
1110 for (lp = lwp_list; lp; lp = lpnext)
1114 if (ptid_get_pid (lp->ptid) == pid)
1117 lwp_list = lp->next;
1119 lpprev->next = lp->next;
1128 /* Return the number of known LWPs in the tgid given by PID. */
1134 struct lwp_info *lp;
1136 for (lp = lwp_list; lp; lp = lp->next)
1137 if (ptid_get_pid (lp->ptid) == pid)
1143 /* Add the LWP specified by PID to the list. Return a pointer to the
1144 structure describing the new LWP. The LWP should already be stopped
1145 (with an exception for the very first LWP). */
1147 static struct lwp_info *
1148 add_lwp (ptid_t ptid)
1150 struct lwp_info *lp;
1152 gdb_assert (is_lwp (ptid));
1154 lp = (struct lwp_info *) xmalloc (sizeof (struct lwp_info));
1156 memset (lp, 0, sizeof (struct lwp_info));
1158 lp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
1163 lp->next = lwp_list;
1166 if (num_lwps (GET_PID (ptid)) > 1 && linux_nat_new_thread != NULL)
1167 linux_nat_new_thread (ptid);
1172 /* Remove the LWP specified by PID from the list. */
1175 delete_lwp (ptid_t ptid)
1177 struct lwp_info *lp, *lpprev;
1181 for (lp = lwp_list; lp; lpprev = lp, lp = lp->next)
1182 if (ptid_equal (lp->ptid, ptid))
1189 lpprev->next = lp->next;
1191 lwp_list = lp->next;
1196 /* Return a pointer to the structure describing the LWP corresponding
1197 to PID. If no corresponding LWP could be found, return NULL. */
1199 static struct lwp_info *
1200 find_lwp_pid (ptid_t ptid)
1202 struct lwp_info *lp;
1206 lwp = GET_LWP (ptid);
1208 lwp = GET_PID (ptid);
1210 for (lp = lwp_list; lp; lp = lp->next)
1211 if (lwp == GET_LWP (lp->ptid))
1217 /* Call CALLBACK with its second argument set to DATA for every LWP in
1218 the list. If CALLBACK returns 1 for a particular LWP, return a
1219 pointer to the structure describing that LWP immediately.
1220 Otherwise return NULL. */
1223 iterate_over_lwps (ptid_t filter,
1224 int (*callback) (struct lwp_info *, void *),
1227 struct lwp_info *lp, *lpnext;
1229 for (lp = lwp_list; lp; lp = lpnext)
1233 if (ptid_match (lp->ptid, filter))
1235 if ((*callback) (lp, data))
1243 /* Update our internal state when changing from one checkpoint to
1244 another indicated by NEW_PTID. We can only switch single-threaded
1245 applications, so we only create one new LWP, and the previous list
1249 linux_nat_switch_fork (ptid_t new_ptid)
1251 struct lwp_info *lp;
1253 purge_lwp_list (GET_PID (inferior_ptid));
1255 lp = add_lwp (new_ptid);
1258 /* This changes the thread's ptid while preserving the gdb thread
1259 num. Also changes the inferior pid, while preserving the
1261 thread_change_ptid (inferior_ptid, new_ptid);
1263 /* We've just told GDB core that the thread changed target id, but,
1264 in fact, it really is a different thread, with different register
1266 registers_changed ();
1269 /* Handle the exit of a single thread LP. */
1272 exit_lwp (struct lwp_info *lp)
1274 struct thread_info *th = find_thread_ptid (lp->ptid);
1278 if (print_thread_events)
1279 printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid));
1281 delete_thread (lp->ptid);
1284 delete_lwp (lp->ptid);
1287 /* Return an lwp's tgid, found in `/proc/PID/status'. */
1290 linux_proc_get_tgid (int lwpid)
1296 snprintf (buf, sizeof (buf), "/proc/%d/status", (int) lwpid);
1297 status_file = fopen (buf, "r");
1298 if (status_file != NULL)
1300 while (fgets (buf, sizeof (buf), status_file))
1302 if (strncmp (buf, "Tgid:", 5) == 0)
1304 tgid = strtoul (buf + strlen ("Tgid:"), NULL, 10);
1309 fclose (status_file);
1315 /* Detect `T (stopped)' in `/proc/PID/status'.
1316 Other states including `T (tracing stop)' are reported as false. */
1319 pid_is_stopped (pid_t pid)
1325 snprintf (buf, sizeof (buf), "/proc/%d/status", (int) pid);
1326 status_file = fopen (buf, "r");
1327 if (status_file != NULL)
1331 while (fgets (buf, sizeof (buf), status_file))
1333 if (strncmp (buf, "State:", 6) == 0)
1339 if (have_state && strstr (buf, "T (stopped)") != NULL)
1341 fclose (status_file);
1346 /* Wait for the LWP specified by LP, which we have just attached to.
1347 Returns a wait status for that LWP, to cache. */
1350 linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned,
1353 pid_t new_pid, pid = GET_LWP (ptid);
1356 if (pid_is_stopped (pid))
1358 if (debug_linux_nat)
1359 fprintf_unfiltered (gdb_stdlog,
1360 "LNPAW: Attaching to a stopped process\n");
1362 /* The process is definitely stopped. It is in a job control
1363 stop, unless the kernel predates the TASK_STOPPED /
1364 TASK_TRACED distinction, in which case it might be in a
1365 ptrace stop. Make sure it is in a ptrace stop; from there we
1366 can kill it, signal it, et cetera.
1368 First make sure there is a pending SIGSTOP. Since we are
1369 already attached, the process can not transition from stopped
1370 to running without a PTRACE_CONT; so we know this signal will
1371 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1372 probably already in the queue (unless this kernel is old
1373 enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP
1374 is not an RT signal, it can only be queued once. */
1375 kill_lwp (pid, SIGSTOP);
1377 /* Finally, resume the stopped process. This will deliver the SIGSTOP
1378 (or a higher priority signal, just like normal PTRACE_ATTACH). */
1379 ptrace (PTRACE_CONT, pid, 0, 0);
1382 /* Make sure the initial process is stopped. The user-level threads
1383 layer might want to poke around in the inferior, and that won't
1384 work if things haven't stabilized yet. */
1385 new_pid = my_waitpid (pid, &status, 0);
1386 if (new_pid == -1 && errno == ECHILD)
1389 warning (_("%s is a cloned process"), target_pid_to_str (ptid));
1391 /* Try again with __WCLONE to check cloned processes. */
1392 new_pid = my_waitpid (pid, &status, __WCLONE);
1396 gdb_assert (pid == new_pid);
1398 if (!WIFSTOPPED (status))
1400 /* The pid we tried to attach has apparently just exited. */
1401 if (debug_linux_nat)
1402 fprintf_unfiltered (gdb_stdlog, "LNPAW: Failed to stop %d: %s",
1403 pid, status_to_str (status));
1407 if (WSTOPSIG (status) != SIGSTOP)
1410 if (debug_linux_nat)
1411 fprintf_unfiltered (gdb_stdlog,
1412 "LNPAW: Received %s after attaching\n",
1413 status_to_str (status));
1419 /* Attach to the LWP specified by PID. Return 0 if successful or -1
1420 if the new LWP could not be attached. */
1423 lin_lwp_attach_lwp (ptid_t ptid)
1425 struct lwp_info *lp;
1428 gdb_assert (is_lwp (ptid));
1430 block_child_signals (&prev_mask);
1432 lp = find_lwp_pid (ptid);
1434 /* We assume that we're already attached to any LWP that has an id
1435 equal to the overall process id, and to any LWP that is already
1436 in our list of LWPs. If we're not seeing exit events from threads
1437 and we've had PID wraparound since we last tried to stop all threads,
1438 this assumption might be wrong; fortunately, this is very unlikely
1440 if (GET_LWP (ptid) != GET_PID (ptid) && lp == NULL)
1442 int status, cloned = 0, signalled = 0;
1444 if (ptrace (PTRACE_ATTACH, GET_LWP (ptid), 0, 0) < 0)
1446 /* If we fail to attach to the thread, issue a warning,
1447 but continue. One way this can happen is if thread
1448 creation is interrupted; as of Linux kernel 2.6.19, a
1449 bug may place threads in the thread list and then fail
1451 warning (_("Can't attach %s: %s"), target_pid_to_str (ptid),
1452 safe_strerror (errno));
1453 restore_child_signals_mask (&prev_mask);
1457 if (debug_linux_nat)
1458 fprintf_unfiltered (gdb_stdlog,
1459 "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n",
1460 target_pid_to_str (ptid));
1462 status = linux_nat_post_attach_wait (ptid, 0, &cloned, &signalled);
1463 if (!WIFSTOPPED (status))
1465 restore_child_signals_mask (&prev_mask);
1469 lp = add_lwp (ptid);
1471 lp->cloned = cloned;
1472 lp->signalled = signalled;
1473 if (WSTOPSIG (status) != SIGSTOP)
1476 lp->status = status;
1479 target_post_attach (GET_LWP (lp->ptid));
1481 if (debug_linux_nat)
1483 fprintf_unfiltered (gdb_stdlog,
1484 "LLAL: waitpid %s received %s\n",
1485 target_pid_to_str (ptid),
1486 status_to_str (status));
1491 /* We assume that the LWP representing the original process is
1492 already stopped. Mark it as stopped in the data structure
1493 that the GNU/linux ptrace layer uses to keep track of
1494 threads. Note that this won't have already been done since
1495 the main thread will have, we assume, been stopped by an
1496 attach from a different layer. */
1498 lp = add_lwp (ptid);
1502 restore_child_signals_mask (&prev_mask);
1507 linux_nat_create_inferior (struct target_ops *ops,
1508 char *exec_file, char *allargs, char **env,
1511 #ifdef HAVE_PERSONALITY
1512 int personality_orig = 0, personality_set = 0;
1513 #endif /* HAVE_PERSONALITY */
1515 /* The fork_child mechanism is synchronous and calls target_wait, so
1516 we have to mask the async mode. */
1518 #ifdef HAVE_PERSONALITY
1519 if (disable_randomization)
1522 personality_orig = personality (0xffffffff);
1523 if (errno == 0 && !(personality_orig & ADDR_NO_RANDOMIZE))
1525 personality_set = 1;
1526 personality (personality_orig | ADDR_NO_RANDOMIZE);
1528 if (errno != 0 || (personality_set
1529 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE)))
1530 warning (_("Error disabling address space randomization: %s"),
1531 safe_strerror (errno));
1533 #endif /* HAVE_PERSONALITY */
1535 /* Make sure we report all signals during startup. */
1536 linux_nat_pass_signals (0, NULL);
1538 linux_ops->to_create_inferior (ops, exec_file, allargs, env, from_tty);
1540 #ifdef HAVE_PERSONALITY
1541 if (personality_set)
1544 personality (personality_orig);
1546 warning (_("Error restoring address space randomization: %s"),
1547 safe_strerror (errno));
1549 #endif /* HAVE_PERSONALITY */
1553 linux_nat_attach (struct target_ops *ops, char *args, int from_tty)
1555 struct lwp_info *lp;
1559 /* Make sure we report all signals during attach. */
1560 linux_nat_pass_signals (0, NULL);
1562 linux_ops->to_attach (ops, args, from_tty);
1564 /* The ptrace base target adds the main thread with (pid,0,0)
1565 format. Decorate it with lwp info. */
1566 ptid = BUILD_LWP (GET_PID (inferior_ptid), GET_PID (inferior_ptid));
1567 thread_change_ptid (inferior_ptid, ptid);
1569 /* Add the initial process as the first LWP to the list. */
1570 lp = add_lwp (ptid);
1572 status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned,
1574 if (!WIFSTOPPED (status))
1576 if (WIFEXITED (status))
1578 int exit_code = WEXITSTATUS (status);
1580 target_terminal_ours ();
1581 target_mourn_inferior ();
1583 error (_("Unable to attach: program exited normally."));
1585 error (_("Unable to attach: program exited with code %d."),
1588 else if (WIFSIGNALED (status))
1590 enum target_signal signo;
1592 target_terminal_ours ();
1593 target_mourn_inferior ();
1595 signo = target_signal_from_host (WTERMSIG (status));
1596 error (_("Unable to attach: program terminated with signal "
1598 target_signal_to_name (signo),
1599 target_signal_to_string (signo));
1602 internal_error (__FILE__, __LINE__,
1603 _("unexpected status %d for PID %ld"),
1604 status, (long) GET_LWP (ptid));
1609 /* Save the wait status to report later. */
1611 if (debug_linux_nat)
1612 fprintf_unfiltered (gdb_stdlog,
1613 "LNA: waitpid %ld, saving status %s\n",
1614 (long) GET_PID (lp->ptid), status_to_str (status));
1616 lp->status = status;
1618 if (target_can_async_p ())
1619 target_async (inferior_event_handler, 0);
1622 /* Get pending status of LP. */
1624 get_pending_status (struct lwp_info *lp, int *status)
1626 enum target_signal signo = TARGET_SIGNAL_0;
1628 /* If we paused threads momentarily, we may have stored pending
1629 events in lp->status or lp->waitstatus (see stop_wait_callback),
1630 and GDB core hasn't seen any signal for those threads.
1631 Otherwise, the last signal reported to the core is found in the
1632 thread object's stop_signal.
1634 There's a corner case that isn't handled here at present. Only
1635 if the thread stopped with a TARGET_WAITKIND_STOPPED does
1636 stop_signal make sense as a real signal to pass to the inferior.
1637 Some catchpoint related events, like
1638 TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set
1639 to TARGET_SIGNAL_SIGTRAP when the catchpoint triggers. But,
1640 those traps are debug API (ptrace in our case) related and
1641 induced; the inferior wouldn't see them if it wasn't being
1642 traced. Hence, we should never pass them to the inferior, even
1643 when set to pass state. Since this corner case isn't handled by
1644 infrun.c when proceeding with a signal, for consistency, neither
1645 do we handle it here (or elsewhere in the file we check for
1646 signal pass state). Normally SIGTRAP isn't set to pass state, so
1647 this is really a corner case. */
1649 if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE)
1650 signo = TARGET_SIGNAL_0; /* a pending ptrace event, not a real signal. */
1651 else if (lp->status)
1652 signo = target_signal_from_host (WSTOPSIG (lp->status));
1653 else if (non_stop && !is_executing (lp->ptid))
1655 struct thread_info *tp = find_thread_ptid (lp->ptid);
1657 signo = tp->suspend.stop_signal;
1661 struct target_waitstatus last;
1664 get_last_target_status (&last_ptid, &last);
1666 if (GET_LWP (lp->ptid) == GET_LWP (last_ptid))
1668 struct thread_info *tp = find_thread_ptid (lp->ptid);
1670 signo = tp->suspend.stop_signal;
1676 if (signo == TARGET_SIGNAL_0)
1678 if (debug_linux_nat)
1679 fprintf_unfiltered (gdb_stdlog,
1680 "GPT: lwp %s has no pending signal\n",
1681 target_pid_to_str (lp->ptid));
1683 else if (!signal_pass_state (signo))
1685 if (debug_linux_nat)
1686 fprintf_unfiltered (gdb_stdlog,
1687 "GPT: lwp %s had signal %s, "
1688 "but it is in no pass state\n",
1689 target_pid_to_str (lp->ptid),
1690 target_signal_to_string (signo));
1694 *status = W_STOPCODE (target_signal_to_host (signo));
1696 if (debug_linux_nat)
1697 fprintf_unfiltered (gdb_stdlog,
1698 "GPT: lwp %s has pending signal %s\n",
1699 target_pid_to_str (lp->ptid),
1700 target_signal_to_string (signo));
1707 detach_callback (struct lwp_info *lp, void *data)
1709 gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status));
1711 if (debug_linux_nat && lp->status)
1712 fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n",
1713 strsignal (WSTOPSIG (lp->status)),
1714 target_pid_to_str (lp->ptid));
1716 /* If there is a pending SIGSTOP, get rid of it. */
1719 if (debug_linux_nat)
1720 fprintf_unfiltered (gdb_stdlog,
1721 "DC: Sending SIGCONT to %s\n",
1722 target_pid_to_str (lp->ptid));
1724 kill_lwp (GET_LWP (lp->ptid), SIGCONT);
1728 /* We don't actually detach from the LWP that has an id equal to the
1729 overall process id just yet. */
1730 if (GET_LWP (lp->ptid) != GET_PID (lp->ptid))
1734 /* Pass on any pending signal for this LWP. */
1735 get_pending_status (lp, &status);
1738 if (ptrace (PTRACE_DETACH, GET_LWP (lp->ptid), 0,
1739 WSTOPSIG (status)) < 0)
1740 error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid),
1741 safe_strerror (errno));
1743 if (debug_linux_nat)
1744 fprintf_unfiltered (gdb_stdlog,
1745 "PTRACE_DETACH (%s, %s, 0) (OK)\n",
1746 target_pid_to_str (lp->ptid),
1747 strsignal (WSTOPSIG (status)));
1749 delete_lwp (lp->ptid);
1756 linux_nat_detach (struct target_ops *ops, char *args, int from_tty)
1760 struct lwp_info *main_lwp;
1762 pid = GET_PID (inferior_ptid);
1764 if (target_can_async_p ())
1765 linux_nat_async (NULL, 0);
1767 /* Stop all threads before detaching. ptrace requires that the
1768 thread is stopped to sucessfully detach. */
1769 iterate_over_lwps (pid_to_ptid (pid), stop_callback, NULL);
1770 /* ... and wait until all of them have reported back that
1771 they're no longer running. */
1772 iterate_over_lwps (pid_to_ptid (pid), stop_wait_callback, NULL);
1774 iterate_over_lwps (pid_to_ptid (pid), detach_callback, NULL);
1776 /* Only the initial process should be left right now. */
1777 gdb_assert (num_lwps (GET_PID (inferior_ptid)) == 1);
1779 main_lwp = find_lwp_pid (pid_to_ptid (pid));
1781 /* Pass on any pending signal for the last LWP. */
1782 if ((args == NULL || *args == '\0')
1783 && get_pending_status (main_lwp, &status) != -1
1784 && WIFSTOPPED (status))
1786 /* Put the signal number in ARGS so that inf_ptrace_detach will
1787 pass it along with PTRACE_DETACH. */
1789 sprintf (args, "%d", (int) WSTOPSIG (status));
1790 if (debug_linux_nat)
1791 fprintf_unfiltered (gdb_stdlog,
1792 "LND: Sending signal %s to %s\n",
1794 target_pid_to_str (main_lwp->ptid));
1797 delete_lwp (main_lwp->ptid);
1799 if (forks_exist_p ())
1801 /* Multi-fork case. The current inferior_ptid is being detached
1802 from, but there are other viable forks to debug. Detach from
1803 the current fork, and context-switch to the first
1805 linux_fork_detach (args, from_tty);
1807 if (non_stop && target_can_async_p ())
1808 target_async (inferior_event_handler, 0);
1811 linux_ops->to_detach (ops, args, from_tty);
1817 resume_callback (struct lwp_info *lp, void *data)
1819 struct inferior *inf = find_inferior_pid (GET_PID (lp->ptid));
1821 if (lp->stopped && inf->vfork_child != NULL)
1823 if (debug_linux_nat)
1824 fprintf_unfiltered (gdb_stdlog,
1825 "RC: Not resuming %s (vfork parent)\n",
1826 target_pid_to_str (lp->ptid));
1828 else if (lp->stopped && lp->status == 0)
1830 if (debug_linux_nat)
1831 fprintf_unfiltered (gdb_stdlog,
1832 "RC: PTRACE_CONT %s, 0, 0 (resuming sibling)\n",
1833 target_pid_to_str (lp->ptid));
1835 linux_ops->to_resume (linux_ops,
1836 pid_to_ptid (GET_LWP (lp->ptid)),
1837 0, TARGET_SIGNAL_0);
1838 if (debug_linux_nat)
1839 fprintf_unfiltered (gdb_stdlog,
1840 "RC: PTRACE_CONT %s, 0, 0 (resume sibling)\n",
1841 target_pid_to_str (lp->ptid));
1844 memset (&lp->siginfo, 0, sizeof (lp->siginfo));
1845 lp->stopped_by_watchpoint = 0;
1847 else if (lp->stopped && debug_linux_nat)
1848 fprintf_unfiltered (gdb_stdlog,
1849 "RC: Not resuming sibling %s (has pending)\n",
1850 target_pid_to_str (lp->ptid));
1851 else if (debug_linux_nat)
1852 fprintf_unfiltered (gdb_stdlog,
1853 "RC: Not resuming sibling %s (not stopped)\n",
1854 target_pid_to_str (lp->ptid));
1860 resume_clear_callback (struct lwp_info *lp, void *data)
1867 resume_set_callback (struct lwp_info *lp, void *data)
1874 linux_nat_resume (struct target_ops *ops,
1875 ptid_t ptid, int step, enum target_signal signo)
1878 struct lwp_info *lp;
1881 if (debug_linux_nat)
1882 fprintf_unfiltered (gdb_stdlog,
1883 "LLR: Preparing to %s %s, %s, inferior_ptid %s\n",
1884 step ? "step" : "resume",
1885 target_pid_to_str (ptid),
1886 (signo != TARGET_SIGNAL_0
1887 ? strsignal (target_signal_to_host (signo)) : "0"),
1888 target_pid_to_str (inferior_ptid));
1890 block_child_signals (&prev_mask);
1892 /* A specific PTID means `step only this process id'. */
1893 resume_many = (ptid_equal (minus_one_ptid, ptid)
1894 || ptid_is_pid (ptid));
1896 /* Mark the lwps we're resuming as resumed. */
1897 iterate_over_lwps (ptid, resume_set_callback, NULL);
1899 /* See if it's the current inferior that should be handled
1902 lp = find_lwp_pid (inferior_ptid);
1904 lp = find_lwp_pid (ptid);
1905 gdb_assert (lp != NULL);
1907 /* Remember if we're stepping. */
1910 /* If we have a pending wait status for this thread, there is no
1911 point in resuming the process. But first make sure that
1912 linux_nat_wait won't preemptively handle the event - we
1913 should never take this short-circuit if we are going to
1914 leave LP running, since we have skipped resuming all the
1915 other threads. This bit of code needs to be synchronized
1916 with linux_nat_wait. */
1918 if (lp->status && WIFSTOPPED (lp->status))
1921 && WSTOPSIG (lp->status)
1922 && sigismember (&pass_mask, WSTOPSIG (lp->status)))
1924 if (debug_linux_nat)
1925 fprintf_unfiltered (gdb_stdlog,
1926 "LLR: Not short circuiting for ignored "
1927 "status 0x%x\n", lp->status);
1929 /* FIXME: What should we do if we are supposed to continue
1930 this thread with a signal? */
1931 gdb_assert (signo == TARGET_SIGNAL_0);
1932 signo = target_signal_from_host (WSTOPSIG (lp->status));
1937 if (lp->status || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE)
1939 /* FIXME: What should we do if we are supposed to continue
1940 this thread with a signal? */
1941 gdb_assert (signo == TARGET_SIGNAL_0);
1943 if (debug_linux_nat)
1944 fprintf_unfiltered (gdb_stdlog,
1945 "LLR: Short circuiting for status 0x%x\n",
1948 restore_child_signals_mask (&prev_mask);
1949 if (target_can_async_p ())
1951 target_async (inferior_event_handler, 0);
1952 /* Tell the event loop we have something to process. */
1958 /* Mark LWP as not stopped to prevent it from being continued by
1963 iterate_over_lwps (ptid, resume_callback, NULL);
1965 /* Convert to something the lower layer understands. */
1966 ptid = pid_to_ptid (GET_LWP (lp->ptid));
1968 linux_ops->to_resume (linux_ops, ptid, step, signo);
1969 memset (&lp->siginfo, 0, sizeof (lp->siginfo));
1970 lp->stopped_by_watchpoint = 0;
1972 if (debug_linux_nat)
1973 fprintf_unfiltered (gdb_stdlog,
1974 "LLR: %s %s, %s (resume event thread)\n",
1975 step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
1976 target_pid_to_str (ptid),
1977 (signo != TARGET_SIGNAL_0
1978 ? strsignal (target_signal_to_host (signo)) : "0"));
1980 restore_child_signals_mask (&prev_mask);
1981 if (target_can_async_p ())
1982 target_async (inferior_event_handler, 0);
1985 /* Send a signal to an LWP. */
1988 kill_lwp (int lwpid, int signo)
1990 /* Use tkill, if possible, in case we are using nptl threads. If tkill
1991 fails, then we are not using nptl threads and we should be using kill. */
1993 #ifdef HAVE_TKILL_SYSCALL
1995 static int tkill_failed;
2002 ret = syscall (__NR_tkill, lwpid, signo);
2003 if (errno != ENOSYS)
2010 return kill (lwpid, signo);
2013 /* Handle a GNU/Linux syscall trap wait response. If we see a syscall
2014 event, check if the core is interested in it: if not, ignore the
2015 event, and keep waiting; otherwise, we need to toggle the LWP's
2016 syscall entry/exit status, since the ptrace event itself doesn't
2017 indicate it, and report the trap to higher layers. */
2020 linux_handle_syscall_trap (struct lwp_info *lp, int stopping)
2022 struct target_waitstatus *ourstatus = &lp->waitstatus;
2023 struct gdbarch *gdbarch = target_thread_architecture (lp->ptid);
2024 int syscall_number = (int) gdbarch_get_syscall_number (gdbarch, lp->ptid);
2028 /* If we're stopping threads, there's a SIGSTOP pending, which
2029 makes it so that the LWP reports an immediate syscall return,
2030 followed by the SIGSTOP. Skip seeing that "return" using
2031 PTRACE_CONT directly, and let stop_wait_callback collect the
2032 SIGSTOP. Later when the thread is resumed, a new syscall
2033 entry event. If we didn't do this (and returned 0), we'd
2034 leave a syscall entry pending, and our caller, by using
2035 PTRACE_CONT to collect the SIGSTOP, skips the syscall return
2036 itself. Later, when the user re-resumes this LWP, we'd see
2037 another syscall entry event and we'd mistake it for a return.
2039 If stop_wait_callback didn't force the SIGSTOP out of the LWP
2040 (leaving immediately with LWP->signalled set, without issuing
2041 a PTRACE_CONT), it would still be problematic to leave this
2042 syscall enter pending, as later when the thread is resumed,
2043 it would then see the same syscall exit mentioned above,
2044 followed by the delayed SIGSTOP, while the syscall didn't
2045 actually get to execute. It seems it would be even more
2046 confusing to the user. */
2048 if (debug_linux_nat)
2049 fprintf_unfiltered (gdb_stdlog,
2050 "LHST: ignoring syscall %d "
2051 "for LWP %ld (stopping threads), "
2052 "resuming with PTRACE_CONT for SIGSTOP\n",
2054 GET_LWP (lp->ptid));
2056 lp->syscall_state = TARGET_WAITKIND_IGNORE;
2057 ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
2061 if (catch_syscall_enabled ())
2063 /* Always update the entry/return state, even if this particular
2064 syscall isn't interesting to the core now. In async mode,
2065 the user could install a new catchpoint for this syscall
2066 between syscall enter/return, and we'll need to know to
2067 report a syscall return if that happens. */
2068 lp->syscall_state = (lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY
2069 ? TARGET_WAITKIND_SYSCALL_RETURN
2070 : TARGET_WAITKIND_SYSCALL_ENTRY);
2072 if (catching_syscall_number (syscall_number))
2074 /* Alright, an event to report. */
2075 ourstatus->kind = lp->syscall_state;
2076 ourstatus->value.syscall_number = syscall_number;
2078 if (debug_linux_nat)
2079 fprintf_unfiltered (gdb_stdlog,
2080 "LHST: stopping for %s of syscall %d"
2083 == TARGET_WAITKIND_SYSCALL_ENTRY
2084 ? "entry" : "return",
2086 GET_LWP (lp->ptid));
2090 if (debug_linux_nat)
2091 fprintf_unfiltered (gdb_stdlog,
2092 "LHST: ignoring %s of syscall %d "
2094 lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY
2095 ? "entry" : "return",
2097 GET_LWP (lp->ptid));
2101 /* If we had been syscall tracing, and hence used PT_SYSCALL
2102 before on this LWP, it could happen that the user removes all
2103 syscall catchpoints before we get to process this event.
2104 There are two noteworthy issues here:
2106 - When stopped at a syscall entry event, resuming with
2107 PT_STEP still resumes executing the syscall and reports a
2110 - Only PT_SYSCALL catches syscall enters. If we last
2111 single-stepped this thread, then this event can't be a
2112 syscall enter. If we last single-stepped this thread, this
2113 has to be a syscall exit.
2115 The points above mean that the next resume, be it PT_STEP or
2116 PT_CONTINUE, can not trigger a syscall trace event. */
2117 if (debug_linux_nat)
2118 fprintf_unfiltered (gdb_stdlog,
2119 "LHST: caught syscall event "
2120 "with no syscall catchpoints."
2121 " %d for LWP %ld, ignoring\n",
2123 GET_LWP (lp->ptid));
2124 lp->syscall_state = TARGET_WAITKIND_IGNORE;
2127 /* The core isn't interested in this event. For efficiency, avoid
2128 stopping all threads only to have the core resume them all again.
2129 Since we're not stopping threads, if we're still syscall tracing
2130 and not stepping, we can't use PTRACE_CONT here, as we'd miss any
2131 subsequent syscall. Simply resume using the inf-ptrace layer,
2132 which knows when to use PT_SYSCALL or PT_CONTINUE. */
2134 /* Note that gdbarch_get_syscall_number may access registers, hence
2136 registers_changed ();
2137 linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
2138 lp->step, TARGET_SIGNAL_0);
2142 /* Handle a GNU/Linux extended wait response. If we see a clone
2143 event, we need to add the new LWP to our list (and not report the
2144 trap to higher layers). This function returns non-zero if the
2145 event should be ignored and we should wait again. If STOPPING is
2146 true, the new LWP remains stopped, otherwise it is continued. */
2149 linux_handle_extended_wait (struct lwp_info *lp, int status,
2152 int pid = GET_LWP (lp->ptid);
2153 struct target_waitstatus *ourstatus = &lp->waitstatus;
2154 int event = status >> 16;
2156 if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK
2157 || event == PTRACE_EVENT_CLONE)
2159 unsigned long new_pid;
2162 ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid);
2164 /* If we haven't already seen the new PID stop, wait for it now. */
2165 if (! pull_pid_from_list (&stopped_pids, new_pid, &status))
2167 /* The new child has a pending SIGSTOP. We can't affect it until it
2168 hits the SIGSTOP, but we're already attached. */
2169 ret = my_waitpid (new_pid, &status,
2170 (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0);
2172 perror_with_name (_("waiting for new child"));
2173 else if (ret != new_pid)
2174 internal_error (__FILE__, __LINE__,
2175 _("wait returned unexpected PID %d"), ret);
2176 else if (!WIFSTOPPED (status))
2177 internal_error (__FILE__, __LINE__,
2178 _("wait returned unexpected status 0x%x"), status);
2181 ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0);
2183 if (event == PTRACE_EVENT_FORK
2184 && linux_fork_checkpointing_p (GET_PID (lp->ptid)))
2186 /* Handle checkpointing by linux-fork.c here as a special
2187 case. We don't want the follow-fork-mode or 'catch fork'
2188 to interfere with this. */
2190 /* This won't actually modify the breakpoint list, but will
2191 physically remove the breakpoints from the child. */
2192 detach_breakpoints (new_pid);
2194 /* Retain child fork in ptrace (stopped) state. */
2195 if (!find_fork_pid (new_pid))
2198 /* Report as spurious, so that infrun doesn't want to follow
2199 this fork. We're actually doing an infcall in
2201 ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
2202 linux_enable_event_reporting (pid_to_ptid (new_pid));
2204 /* Report the stop to the core. */
2208 if (event == PTRACE_EVENT_FORK)
2209 ourstatus->kind = TARGET_WAITKIND_FORKED;
2210 else if (event == PTRACE_EVENT_VFORK)
2211 ourstatus->kind = TARGET_WAITKIND_VFORKED;
2214 struct lwp_info *new_lp;
2216 ourstatus->kind = TARGET_WAITKIND_IGNORE;
2218 new_lp = add_lwp (BUILD_LWP (new_pid, GET_PID (lp->ptid)));
2220 new_lp->stopped = 1;
2222 if (WSTOPSIG (status) != SIGSTOP)
2224 /* This can happen if someone starts sending signals to
2225 the new thread before it gets a chance to run, which
2226 have a lower number than SIGSTOP (e.g. SIGUSR1).
2227 This is an unlikely case, and harder to handle for
2228 fork / vfork than for clone, so we do not try - but
2229 we handle it for clone events here. We'll send
2230 the other signal on to the thread below. */
2232 new_lp->signalled = 1;
2239 /* Add the new thread to GDB's lists as soon as possible
2242 1) the frontend doesn't have to wait for a stop to
2245 2) we tag it with the correct running state. */
2247 /* If the thread_db layer is active, let it know about
2248 this new thread, and add it to GDB's list. */
2249 if (!thread_db_attach_lwp (new_lp->ptid))
2251 /* We're not using thread_db. Add it to GDB's
2253 target_post_attach (GET_LWP (new_lp->ptid));
2254 add_thread (new_lp->ptid);
2259 set_running (new_lp->ptid, 1);
2260 set_executing (new_lp->ptid, 1);
2264 /* Note the need to use the low target ops to resume, to
2265 handle resuming with PT_SYSCALL if we have syscall
2269 enum target_signal signo;
2271 new_lp->stopped = 0;
2272 new_lp->resumed = 1;
2275 ? target_signal_from_host (WSTOPSIG (status))
2278 linux_ops->to_resume (linux_ops, pid_to_ptid (new_pid),
2285 /* We created NEW_LP so it cannot yet contain STATUS. */
2286 gdb_assert (new_lp->status == 0);
2288 /* Save the wait status to report later. */
2289 if (debug_linux_nat)
2290 fprintf_unfiltered (gdb_stdlog,
2291 "LHEW: waitpid of new LWP %ld, "
2292 "saving status %s\n",
2293 (long) GET_LWP (new_lp->ptid),
2294 status_to_str (status));
2295 new_lp->status = status;
2299 if (debug_linux_nat)
2300 fprintf_unfiltered (gdb_stdlog,
2301 "LHEW: Got clone event "
2302 "from LWP %ld, resuming\n",
2303 GET_LWP (lp->ptid));
2304 linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
2305 0, TARGET_SIGNAL_0);
2313 if (event == PTRACE_EVENT_EXEC)
2315 if (debug_linux_nat)
2316 fprintf_unfiltered (gdb_stdlog,
2317 "LHEW: Got exec event from LWP %ld\n",
2318 GET_LWP (lp->ptid));
2320 ourstatus->kind = TARGET_WAITKIND_EXECD;
2321 ourstatus->value.execd_pathname
2322 = xstrdup (linux_child_pid_to_exec_file (pid));
2327 if (event == PTRACE_EVENT_VFORK_DONE)
2329 if (current_inferior ()->waiting_for_vfork_done)
2331 if (debug_linux_nat)
2332 fprintf_unfiltered (gdb_stdlog,
2333 "LHEW: Got expected PTRACE_EVENT_"
2334 "VFORK_DONE from LWP %ld: stopping\n",
2335 GET_LWP (lp->ptid));
2337 ourstatus->kind = TARGET_WAITKIND_VFORK_DONE;
2341 if (debug_linux_nat)
2342 fprintf_unfiltered (gdb_stdlog,
2343 "LHEW: Got PTRACE_EVENT_VFORK_DONE "
2344 "from LWP %ld: resuming\n",
2345 GET_LWP (lp->ptid));
2346 ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
2350 internal_error (__FILE__, __LINE__,
2351 _("unknown ptrace event %d"), event);
2354 /* Return non-zero if LWP is a zombie. */
2357 linux_lwp_is_zombie (long lwp)
2359 char buffer[MAXPATHLEN];
2363 xsnprintf (buffer, sizeof (buffer), "/proc/%ld/status", lwp);
2364 procfile = fopen (buffer, "r");
2365 if (procfile == NULL)
2367 warning (_("unable to open /proc file '%s'"), buffer);
2370 while (fgets (buffer, sizeof (buffer), procfile) != NULL)
2371 if (strcmp (buffer, "State:\tZ (zombie)\n") == 0)
2381 /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has
2385 wait_lwp (struct lwp_info *lp)
2389 int thread_dead = 0;
2392 gdb_assert (!lp->stopped);
2393 gdb_assert (lp->status == 0);
2395 /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */
2396 block_child_signals (&prev_mask);
2400 /* If my_waitpid returns 0 it means the __WCLONE vs. non-__WCLONE kind
2401 was right and we should just call sigsuspend. */
2403 pid = my_waitpid (GET_LWP (lp->ptid), &status, WNOHANG);
2404 if (pid == -1 && errno == ECHILD)
2405 pid = my_waitpid (GET_LWP (lp->ptid), &status, __WCLONE | WNOHANG);
2409 /* Bugs 10970, 12702.
2410 Thread group leader may have exited in which case we'll lock up in
2411 waitpid if there are other threads, even if they are all zombies too.
2412 Basically, we're not supposed to use waitpid this way.
2413 __WCLONE is not applicable for the leader so we can't use that.
2414 LINUX_NAT_THREAD_ALIVE cannot be used here as it requires a STOPPED
2415 process; it gets ESRCH both for the zombie and for running processes.
2417 As a workaround, check if we're waiting for the thread group leader and
2418 if it's a zombie, and avoid calling waitpid if it is.
2420 This is racy, what if the tgl becomes a zombie right after we check?
2421 Therefore always use WNOHANG with sigsuspend - it is equivalent to
2422 waiting waitpid but the linux_lwp_is_zombie is safe this way. */
2424 if (GET_PID (lp->ptid) == GET_LWP (lp->ptid)
2425 && linux_lwp_is_zombie (GET_LWP (lp->ptid)))
2428 if (debug_linux_nat)
2429 fprintf_unfiltered (gdb_stdlog,
2430 "WL: Thread group leader %s vanished.\n",
2431 target_pid_to_str (lp->ptid));
2435 /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers
2436 get invoked despite our caller had them intentionally blocked by
2437 block_child_signals. This is sensitive only to the loop of
2438 linux_nat_wait_1 and there if we get called my_waitpid gets called
2439 again before it gets to sigsuspend so we can safely let the handlers
2440 get executed here. */
2442 sigsuspend (&suspend_mask);
2445 restore_child_signals_mask (&prev_mask);
2447 if (pid == -1 && errno == ECHILD)
2449 /* The thread has previously exited. We need to delete it
2450 now because, for some vendor 2.4 kernels with NPTL
2451 support backported, there won't be an exit event unless
2452 it is the main thread. 2.6 kernels will report an exit
2453 event for each thread that exits, as expected. */
2455 if (debug_linux_nat)
2456 fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n",
2457 target_pid_to_str (lp->ptid));
2462 gdb_assert (pid == GET_LWP (lp->ptid));
2464 if (debug_linux_nat)
2466 fprintf_unfiltered (gdb_stdlog,
2467 "WL: waitpid %s received %s\n",
2468 target_pid_to_str (lp->ptid),
2469 status_to_str (status));
2473 /* Check if the thread has exited. */
2474 if (WIFEXITED (status) || WIFSIGNALED (status))
2477 if (debug_linux_nat)
2478 fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n",
2479 target_pid_to_str (lp->ptid));
2488 gdb_assert (WIFSTOPPED (status));
2490 /* Handle GNU/Linux's syscall SIGTRAPs. */
2491 if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP)
2493 /* No longer need the sysgood bit. The ptrace event ends up
2494 recorded in lp->waitstatus if we care for it. We can carry
2495 on handling the event like a regular SIGTRAP from here
2497 status = W_STOPCODE (SIGTRAP);
2498 if (linux_handle_syscall_trap (lp, 1))
2499 return wait_lwp (lp);
2502 /* Handle GNU/Linux's extended waitstatus for trace events. */
2503 if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
2505 if (debug_linux_nat)
2506 fprintf_unfiltered (gdb_stdlog,
2507 "WL: Handling extended status 0x%06x\n",
2509 if (linux_handle_extended_wait (lp, status, 1))
2510 return wait_lwp (lp);
2516 /* Save the most recent siginfo for LP. This is currently only called
2517 for SIGTRAP; some ports use the si_addr field for
2518 target_stopped_data_address. In the future, it may also be used to
2519 restore the siginfo of requeued signals. */
2522 save_siginfo (struct lwp_info *lp)
2525 ptrace (PTRACE_GETSIGINFO, GET_LWP (lp->ptid),
2526 (PTRACE_TYPE_ARG3) 0, &lp->siginfo);
2529 memset (&lp->siginfo, 0, sizeof (lp->siginfo));
2532 /* Send a SIGSTOP to LP. */
2535 stop_callback (struct lwp_info *lp, void *data)
2537 if (!lp->stopped && !lp->signalled)
2541 if (debug_linux_nat)
2543 fprintf_unfiltered (gdb_stdlog,
2544 "SC: kill %s **<SIGSTOP>**\n",
2545 target_pid_to_str (lp->ptid));
2548 ret = kill_lwp (GET_LWP (lp->ptid), SIGSTOP);
2549 if (debug_linux_nat)
2551 fprintf_unfiltered (gdb_stdlog,
2552 "SC: lwp kill %d %s\n",
2554 errno ? safe_strerror (errno) : "ERRNO-OK");
2558 gdb_assert (lp->status == 0);
2564 /* Return non-zero if LWP PID has a pending SIGINT. */
2567 linux_nat_has_pending_sigint (int pid)
2569 sigset_t pending, blocked, ignored;
2571 linux_proc_pending_signals (pid, &pending, &blocked, &ignored);
2573 if (sigismember (&pending, SIGINT)
2574 && !sigismember (&ignored, SIGINT))
2580 /* Set a flag in LP indicating that we should ignore its next SIGINT. */
2583 set_ignore_sigint (struct lwp_info *lp, void *data)
2585 /* If a thread has a pending SIGINT, consume it; otherwise, set a
2586 flag to consume the next one. */
2587 if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status)
2588 && WSTOPSIG (lp->status) == SIGINT)
2591 lp->ignore_sigint = 1;
2596 /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag.
2597 This function is called after we know the LWP has stopped; if the LWP
2598 stopped before the expected SIGINT was delivered, then it will never have
2599 arrived. Also, if the signal was delivered to a shared queue and consumed
2600 by a different thread, it will never be delivered to this LWP. */
2603 maybe_clear_ignore_sigint (struct lwp_info *lp)
2605 if (!lp->ignore_sigint)
2608 if (!linux_nat_has_pending_sigint (GET_LWP (lp->ptid)))
2610 if (debug_linux_nat)
2611 fprintf_unfiltered (gdb_stdlog,
2612 "MCIS: Clearing bogus flag for %s\n",
2613 target_pid_to_str (lp->ptid));
2614 lp->ignore_sigint = 0;
2618 /* Fetch the possible triggered data watchpoint info and store it in
2621 On some archs, like x86, that use debug registers to set
2622 watchpoints, it's possible that the way to know which watched
2623 address trapped, is to check the register that is used to select
2624 which address to watch. Problem is, between setting the watchpoint
2625 and reading back which data address trapped, the user may change
2626 the set of watchpoints, and, as a consequence, GDB changes the
2627 debug registers in the inferior. To avoid reading back a stale
2628 stopped-data-address when that happens, we cache in LP the fact
2629 that a watchpoint trapped, and the corresponding data address, as
2630 soon as we see LP stop with a SIGTRAP. If GDB changes the debug
2631 registers meanwhile, we have the cached data we can rely on. */
2634 save_sigtrap (struct lwp_info *lp)
2636 struct cleanup *old_chain;
2638 if (linux_ops->to_stopped_by_watchpoint == NULL)
2640 lp->stopped_by_watchpoint = 0;
2644 old_chain = save_inferior_ptid ();
2645 inferior_ptid = lp->ptid;
2647 lp->stopped_by_watchpoint = linux_ops->to_stopped_by_watchpoint ();
2649 if (lp->stopped_by_watchpoint)
2651 if (linux_ops->to_stopped_data_address != NULL)
2652 lp->stopped_data_address_p =
2653 linux_ops->to_stopped_data_address (¤t_target,
2654 &lp->stopped_data_address);
2656 lp->stopped_data_address_p = 0;
2659 do_cleanups (old_chain);
2662 /* See save_sigtrap. */
2665 linux_nat_stopped_by_watchpoint (void)
2667 struct lwp_info *lp = find_lwp_pid (inferior_ptid);
2669 gdb_assert (lp != NULL);
2671 return lp->stopped_by_watchpoint;
2675 linux_nat_stopped_data_address (struct target_ops *ops, CORE_ADDR *addr_p)
2677 struct lwp_info *lp = find_lwp_pid (inferior_ptid);
2679 gdb_assert (lp != NULL);
2681 *addr_p = lp->stopped_data_address;
2683 return lp->stopped_data_address_p;
2686 /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */
2689 sigtrap_is_event (int status)
2691 return WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP;
2694 /* SIGTRAP-like events recognizer. */
2696 static int (*linux_nat_status_is_event) (int status) = sigtrap_is_event;
2698 /* Check for SIGTRAP-like events in LP. */
2701 linux_nat_lp_status_is_event (struct lwp_info *lp)
2703 /* We check for lp->waitstatus in addition to lp->status, because we can
2704 have pending process exits recorded in lp->status
2705 and W_EXITCODE(0,0) == 0. We should probably have an additional
2706 lp->status_p flag. */
2708 return (lp->waitstatus.kind == TARGET_WAITKIND_IGNORE
2709 && linux_nat_status_is_event (lp->status));
2712 /* Set alternative SIGTRAP-like events recognizer. If
2713 breakpoint_inserted_here_p there then gdbarch_decr_pc_after_break will be
2717 linux_nat_set_status_is_event (struct target_ops *t,
2718 int (*status_is_event) (int status))
2720 linux_nat_status_is_event = status_is_event;
2723 /* Wait until LP is stopped. */
2726 stop_wait_callback (struct lwp_info *lp, void *data)
2728 struct inferior *inf = find_inferior_pid (GET_PID (lp->ptid));
2730 /* If this is a vfork parent, bail out, it is not going to report
2731 any SIGSTOP until the vfork is done with. */
2732 if (inf->vfork_child != NULL)
2739 status = wait_lwp (lp);
2743 if (lp->ignore_sigint && WIFSTOPPED (status)
2744 && WSTOPSIG (status) == SIGINT)
2746 lp->ignore_sigint = 0;
2749 ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
2750 if (debug_linux_nat)
2751 fprintf_unfiltered (gdb_stdlog,
2752 "PTRACE_CONT %s, 0, 0 (%s) "
2753 "(discarding SIGINT)\n",
2754 target_pid_to_str (lp->ptid),
2755 errno ? safe_strerror (errno) : "OK");
2757 return stop_wait_callback (lp, NULL);
2760 maybe_clear_ignore_sigint (lp);
2762 if (WSTOPSIG (status) != SIGSTOP)
2764 if (linux_nat_status_is_event (status))
2766 /* If a LWP other than the LWP that we're reporting an
2767 event for has hit a GDB breakpoint (as opposed to
2768 some random trap signal), then just arrange for it to
2769 hit it again later. We don't keep the SIGTRAP status
2770 and don't forward the SIGTRAP signal to the LWP. We
2771 will handle the current event, eventually we will
2772 resume all LWPs, and this one will get its breakpoint
2775 If we do not do this, then we run the risk that the
2776 user will delete or disable the breakpoint, but the
2777 thread will have already tripped on it. */
2779 /* Save the trap's siginfo in case we need it later. */
2784 /* Now resume this LWP and get the SIGSTOP event. */
2786 ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
2787 if (debug_linux_nat)
2789 fprintf_unfiltered (gdb_stdlog,
2790 "PTRACE_CONT %s, 0, 0 (%s)\n",
2791 target_pid_to_str (lp->ptid),
2792 errno ? safe_strerror (errno) : "OK");
2794 fprintf_unfiltered (gdb_stdlog,
2795 "SWC: Candidate SIGTRAP event in %s\n",
2796 target_pid_to_str (lp->ptid));
2798 /* Hold this event/waitstatus while we check to see if
2799 there are any more (we still want to get that SIGSTOP). */
2800 stop_wait_callback (lp, NULL);
2802 /* Hold the SIGTRAP for handling by linux_nat_wait. If
2803 there's another event, throw it back into the
2807 if (debug_linux_nat)
2808 fprintf_unfiltered (gdb_stdlog,
2809 "SWC: kill %s, %s\n",
2810 target_pid_to_str (lp->ptid),
2811 status_to_str ((int) status));
2812 kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (lp->status));
2815 /* Save the sigtrap event. */
2816 lp->status = status;
2821 /* The thread was stopped with a signal other than
2822 SIGSTOP, and didn't accidentally trip a breakpoint. */
2824 if (debug_linux_nat)
2826 fprintf_unfiltered (gdb_stdlog,
2827 "SWC: Pending event %s in %s\n",
2828 status_to_str ((int) status),
2829 target_pid_to_str (lp->ptid));
2831 /* Now resume this LWP and get the SIGSTOP event. */
2833 ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
2834 if (debug_linux_nat)
2835 fprintf_unfiltered (gdb_stdlog,
2836 "SWC: PTRACE_CONT %s, 0, 0 (%s)\n",
2837 target_pid_to_str (lp->ptid),
2838 errno ? safe_strerror (errno) : "OK");
2840 /* Hold this event/waitstatus while we check to see if
2841 there are any more (we still want to get that SIGSTOP). */
2842 stop_wait_callback (lp, NULL);
2844 /* If the lp->status field is still empty, use it to
2845 hold this event. If not, then this event must be
2846 returned to the event queue of the LWP. */
2849 if (debug_linux_nat)
2851 fprintf_unfiltered (gdb_stdlog,
2852 "SWC: kill %s, %s\n",
2853 target_pid_to_str (lp->ptid),
2854 status_to_str ((int) status));
2856 kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status));
2859 lp->status = status;
2865 /* We caught the SIGSTOP that we intended to catch, so
2866 there's no SIGSTOP pending. */
2875 /* Return non-zero if LP has a wait status pending. */
2878 status_callback (struct lwp_info *lp, void *data)
2880 /* Only report a pending wait status if we pretend that this has
2881 indeed been resumed. */
2885 if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE)
2887 /* A ptrace event, like PTRACE_FORK|VFORK|EXEC, syscall event,
2888 or a pending process exit. Note that `W_EXITCODE(0,0) ==
2889 0', so a clean process exit can not be stored pending in
2890 lp->status, it is indistinguishable from
2891 no-pending-status. */
2895 if (lp->status != 0)
2901 /* Return non-zero if LP isn't stopped. */
2904 running_callback (struct lwp_info *lp, void *data)
2906 return (lp->stopped == 0 || (lp->status != 0 && lp->resumed));
2909 /* Count the LWP's that have had events. */
2912 count_events_callback (struct lwp_info *lp, void *data)
2916 gdb_assert (count != NULL);
2918 /* Count only resumed LWPs that have a SIGTRAP event pending. */
2919 if (lp->resumed && linux_nat_lp_status_is_event (lp))
2925 /* Select the LWP (if any) that is currently being single-stepped. */
2928 select_singlestep_lwp_callback (struct lwp_info *lp, void *data)
2930 if (lp->step && lp->status != 0)
2936 /* Select the Nth LWP that has had a SIGTRAP event. */
2939 select_event_lwp_callback (struct lwp_info *lp, void *data)
2941 int *selector = data;
2943 gdb_assert (selector != NULL);
2945 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2946 if (lp->resumed && linux_nat_lp_status_is_event (lp))
2947 if ((*selector)-- == 0)
2954 cancel_breakpoint (struct lwp_info *lp)
2956 /* Arrange for a breakpoint to be hit again later. We don't keep
2957 the SIGTRAP status and don't forward the SIGTRAP signal to the
2958 LWP. We will handle the current event, eventually we will resume
2959 this LWP, and this breakpoint will trap again.
2961 If we do not do this, then we run the risk that the user will
2962 delete or disable the breakpoint, but the LWP will have already
2965 struct regcache *regcache = get_thread_regcache (lp->ptid);
2966 struct gdbarch *gdbarch = get_regcache_arch (regcache);
2969 pc = regcache_read_pc (regcache) - gdbarch_decr_pc_after_break (gdbarch);
2970 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc))
2972 if (debug_linux_nat)
2973 fprintf_unfiltered (gdb_stdlog,
2974 "CB: Push back breakpoint for %s\n",
2975 target_pid_to_str (lp->ptid));
2977 /* Back up the PC if necessary. */
2978 if (gdbarch_decr_pc_after_break (gdbarch))
2979 regcache_write_pc (regcache, pc);
2987 cancel_breakpoints_callback (struct lwp_info *lp, void *data)
2989 struct lwp_info *event_lp = data;
2991 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
2995 /* If a LWP other than the LWP that we're reporting an event for has
2996 hit a GDB breakpoint (as opposed to some random trap signal),
2997 then just arrange for it to hit it again later. We don't keep
2998 the SIGTRAP status and don't forward the SIGTRAP signal to the
2999 LWP. We will handle the current event, eventually we will resume
3000 all LWPs, and this one will get its breakpoint trap again.
3002 If we do not do this, then we run the risk that the user will
3003 delete or disable the breakpoint, but the LWP will have already
3006 if (linux_nat_lp_status_is_event (lp)
3007 && cancel_breakpoint (lp))
3008 /* Throw away the SIGTRAP. */
3014 /* Select one LWP out of those that have events pending. */
3017 select_event_lwp (ptid_t filter, struct lwp_info **orig_lp, int *status)
3020 int random_selector;
3021 struct lwp_info *event_lp;
3023 /* Record the wait status for the original LWP. */
3024 (*orig_lp)->status = *status;
3026 /* Give preference to any LWP that is being single-stepped. */
3027 event_lp = iterate_over_lwps (filter,
3028 select_singlestep_lwp_callback, NULL);
3029 if (event_lp != NULL)
3031 if (debug_linux_nat)
3032 fprintf_unfiltered (gdb_stdlog,
3033 "SEL: Select single-step %s\n",
3034 target_pid_to_str (event_lp->ptid));
3038 /* No single-stepping LWP. Select one at random, out of those
3039 which have had SIGTRAP events. */
3041 /* First see how many SIGTRAP events we have. */
3042 iterate_over_lwps (filter, count_events_callback, &num_events);
3044 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
3045 random_selector = (int)
3046 ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
3048 if (debug_linux_nat && num_events > 1)
3049 fprintf_unfiltered (gdb_stdlog,
3050 "SEL: Found %d SIGTRAP events, selecting #%d\n",
3051 num_events, random_selector);
3053 event_lp = iterate_over_lwps (filter,
3054 select_event_lwp_callback,
3058 if (event_lp != NULL)
3060 /* Switch the event LWP. */
3061 *orig_lp = event_lp;
3062 *status = event_lp->status;
3065 /* Flush the wait status for the event LWP. */
3066 (*orig_lp)->status = 0;
3069 /* Return non-zero if LP has been resumed. */
3072 resumed_callback (struct lwp_info *lp, void *data)
3077 /* Stop an active thread, verify it still exists, then resume it. */
3080 stop_and_resume_callback (struct lwp_info *lp, void *data)
3082 struct lwp_info *ptr;
3084 if (!lp->stopped && !lp->signalled)
3086 stop_callback (lp, NULL);
3087 stop_wait_callback (lp, NULL);
3088 /* Resume if the lwp still exists. */
3089 for (ptr = lwp_list; ptr; ptr = ptr->next)
3092 resume_callback (lp, NULL);
3093 resume_set_callback (lp, NULL);
3099 /* Check if we should go on and pass this event to common code.
3100 Return the affected lwp if we are, or NULL otherwise. */
3101 static struct lwp_info *
3102 linux_nat_filter_event (int lwpid, int status, int options)
3104 struct lwp_info *lp;
3106 lp = find_lwp_pid (pid_to_ptid (lwpid));
3108 /* Check for stop events reported by a process we didn't already
3109 know about - anything not already in our LWP list.
3111 If we're expecting to receive stopped processes after
3112 fork, vfork, and clone events, then we'll just add the
3113 new one to our list and go back to waiting for the event
3114 to be reported - the stopped process might be returned
3115 from waitpid before or after the event is. */
3116 if (WIFSTOPPED (status) && !lp)
3118 linux_record_stopped_pid (lwpid, status);
3122 /* Make sure we don't report an event for the exit of an LWP not in
3123 our list, i.e. not part of the current process. This can happen
3124 if we detach from a program we originally forked and then it
3126 if (!WIFSTOPPED (status) && !lp)
3129 /* NOTE drow/2003-06-17: This code seems to be meant for debugging
3130 CLONE_PTRACE processes which do not use the thread library -
3131 otherwise we wouldn't find the new LWP this way. That doesn't
3132 currently work, and the following code is currently unreachable
3133 due to the two blocks above. If it's fixed some day, this code
3134 should be broken out into a function so that we can also pick up
3135 LWPs from the new interface. */
3138 lp = add_lwp (BUILD_LWP (lwpid, GET_PID (inferior_ptid)));
3139 if (options & __WCLONE)
3142 gdb_assert (WIFSTOPPED (status)
3143 && WSTOPSIG (status) == SIGSTOP);
3146 if (!in_thread_list (inferior_ptid))
3148 inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid),
3149 GET_PID (inferior_ptid));
3150 add_thread (inferior_ptid);
3153 add_thread (lp->ptid);
3156 /* Handle GNU/Linux's syscall SIGTRAPs. */
3157 if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP)
3159 /* No longer need the sysgood bit. The ptrace event ends up
3160 recorded in lp->waitstatus if we care for it. We can carry
3161 on handling the event like a regular SIGTRAP from here
3163 status = W_STOPCODE (SIGTRAP);
3164 if (linux_handle_syscall_trap (lp, 0))
3168 /* Handle GNU/Linux's extended waitstatus for trace events. */
3169 if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
3171 if (debug_linux_nat)
3172 fprintf_unfiltered (gdb_stdlog,
3173 "LLW: Handling extended status 0x%06x\n",
3175 if (linux_handle_extended_wait (lp, status, 0))
3179 if (linux_nat_status_is_event (status))
3181 /* Save the trap's siginfo in case we need it later. */
3187 /* Check if the thread has exited. */
3188 if ((WIFEXITED (status) || WIFSIGNALED (status))
3189 && num_lwps (GET_PID (lp->ptid)) > 1)
3191 /* If this is the main thread, we must stop all threads and verify
3192 if they are still alive. This is because in the nptl thread model
3193 on Linux 2.4, there is no signal issued for exiting LWPs
3194 other than the main thread. We only get the main thread exit
3195 signal once all child threads have already exited. If we
3196 stop all the threads and use the stop_wait_callback to check
3197 if they have exited we can determine whether this signal
3198 should be ignored or whether it means the end of the debugged
3199 application, regardless of which threading model is being
3201 if (GET_PID (lp->ptid) == GET_LWP (lp->ptid))
3204 iterate_over_lwps (pid_to_ptid (GET_PID (lp->ptid)),
3205 stop_and_resume_callback, NULL);
3208 if (debug_linux_nat)
3209 fprintf_unfiltered (gdb_stdlog,
3210 "LLW: %s exited.\n",
3211 target_pid_to_str (lp->ptid));
3213 if (num_lwps (GET_PID (lp->ptid)) > 1)
3215 /* If there is at least one more LWP, then the exit signal
3216 was not the end of the debugged application and should be
3223 /* Check if the current LWP has previously exited. In the nptl
3224 thread model, LWPs other than the main thread do not issue
3225 signals when they exit so we must check whenever the thread has
3226 stopped. A similar check is made in stop_wait_callback(). */
3227 if (num_lwps (GET_PID (lp->ptid)) > 1 && !linux_thread_alive (lp->ptid))
3229 ptid_t ptid = pid_to_ptid (GET_PID (lp->ptid));
3231 if (debug_linux_nat)
3232 fprintf_unfiltered (gdb_stdlog,
3233 "LLW: %s exited.\n",
3234 target_pid_to_str (lp->ptid));
3238 /* Make sure there is at least one thread running. */
3239 gdb_assert (iterate_over_lwps (ptid, running_callback, NULL));
3241 /* Discard the event. */
3245 /* Make sure we don't report a SIGSTOP that we sent ourselves in
3246 an attempt to stop an LWP. */
3248 && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP)
3250 if (debug_linux_nat)
3251 fprintf_unfiltered (gdb_stdlog,
3252 "LLW: Delayed SIGSTOP caught for %s.\n",
3253 target_pid_to_str (lp->ptid));
3255 /* This is a delayed SIGSTOP. */
3258 registers_changed ();
3260 linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
3261 lp->step, TARGET_SIGNAL_0);
3262 if (debug_linux_nat)
3263 fprintf_unfiltered (gdb_stdlog,
3264 "LLW: %s %s, 0, 0 (discard SIGSTOP)\n",
3266 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3267 target_pid_to_str (lp->ptid));
3270 gdb_assert (lp->resumed);
3272 /* Discard the event. */
3276 /* Make sure we don't report a SIGINT that we have already displayed
3277 for another thread. */
3278 if (lp->ignore_sigint
3279 && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT)
3281 if (debug_linux_nat)
3282 fprintf_unfiltered (gdb_stdlog,
3283 "LLW: Delayed SIGINT caught for %s.\n",
3284 target_pid_to_str (lp->ptid));
3286 /* This is a delayed SIGINT. */
3287 lp->ignore_sigint = 0;
3289 registers_changed ();
3290 linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
3291 lp->step, TARGET_SIGNAL_0);
3292 if (debug_linux_nat)
3293 fprintf_unfiltered (gdb_stdlog,
3294 "LLW: %s %s, 0, 0 (discard SIGINT)\n",
3296 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3297 target_pid_to_str (lp->ptid));
3300 gdb_assert (lp->resumed);
3302 /* Discard the event. */
3306 /* An interesting event. */
3308 lp->status = status;
3313 linux_nat_wait_1 (struct target_ops *ops,
3314 ptid_t ptid, struct target_waitstatus *ourstatus,
3317 static sigset_t prev_mask;
3318 struct lwp_info *lp = NULL;
3323 if (debug_linux_nat)
3324 fprintf_unfiltered (gdb_stdlog, "LLW: enter\n");
3326 /* The first time we get here after starting a new inferior, we may
3327 not have added it to the LWP list yet - this is the earliest
3328 moment at which we know its PID. */
3329 if (ptid_is_pid (inferior_ptid))
3331 /* Upgrade the main thread's ptid. */
3332 thread_change_ptid (inferior_ptid,
3333 BUILD_LWP (GET_PID (inferior_ptid),
3334 GET_PID (inferior_ptid)));
3336 lp = add_lwp (inferior_ptid);
3340 /* Make sure SIGCHLD is blocked. */
3341 block_child_signals (&prev_mask);
3343 if (ptid_equal (ptid, minus_one_ptid))
3345 else if (ptid_is_pid (ptid))
3346 /* A request to wait for a specific tgid. This is not possible
3347 with waitpid, so instead, we wait for any child, and leave
3348 children we're not interested in right now with a pending
3349 status to report later. */
3352 pid = GET_LWP (ptid);
3358 /* Make sure that of those LWPs we want to get an event from, there
3359 is at least one LWP that has been resumed. If there's none, just
3360 bail out. The core may just be flushing asynchronously all
3362 if (iterate_over_lwps (ptid, resumed_callback, NULL) == NULL)
3364 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3366 if (debug_linux_nat)
3367 fprintf_unfiltered (gdb_stdlog, "LLW: exit (no resumed LWP)\n");
3369 restore_child_signals_mask (&prev_mask);
3370 return minus_one_ptid;
3373 /* First check if there is a LWP with a wait status pending. */
3376 /* Any LWP that's been resumed will do. */
3377 lp = iterate_over_lwps (ptid, status_callback, NULL);
3380 if (debug_linux_nat && lp->status)
3381 fprintf_unfiltered (gdb_stdlog,
3382 "LLW: Using pending wait status %s for %s.\n",
3383 status_to_str (lp->status),
3384 target_pid_to_str (lp->ptid));
3387 /* But if we don't find one, we'll have to wait, and check both
3388 cloned and uncloned processes. We start with the cloned
3390 options = __WCLONE | WNOHANG;
3392 else if (is_lwp (ptid))
3394 if (debug_linux_nat)
3395 fprintf_unfiltered (gdb_stdlog,
3396 "LLW: Waiting for specific LWP %s.\n",
3397 target_pid_to_str (ptid));
3399 /* We have a specific LWP to check. */
3400 lp = find_lwp_pid (ptid);
3403 if (debug_linux_nat && lp->status)
3404 fprintf_unfiltered (gdb_stdlog,
3405 "LLW: Using pending wait status %s for %s.\n",
3406 status_to_str (lp->status),
3407 target_pid_to_str (lp->ptid));
3409 /* If we have to wait, take into account whether PID is a cloned
3410 process or not. And we have to convert it to something that
3411 the layer beneath us can understand. */
3412 options = lp->cloned ? __WCLONE : 0;
3413 pid = GET_LWP (ptid);
3415 /* We check for lp->waitstatus in addition to lp->status,
3416 because we can have pending process exits recorded in
3417 lp->status and W_EXITCODE(0,0) == 0. We should probably have
3418 an additional lp->status_p flag. */
3419 if (lp->status == 0 && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE)
3423 if (lp && lp->signalled)
3425 /* A pending SIGSTOP may interfere with the normal stream of
3426 events. In a typical case where interference is a problem,
3427 we have a SIGSTOP signal pending for LWP A while
3428 single-stepping it, encounter an event in LWP B, and take the
3429 pending SIGSTOP while trying to stop LWP A. After processing
3430 the event in LWP B, LWP A is continued, and we'll never see
3431 the SIGTRAP associated with the last time we were
3432 single-stepping LWP A. */
3434 /* Resume the thread. It should halt immediately returning the
3436 registers_changed ();
3437 linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
3438 lp->step, TARGET_SIGNAL_0);
3439 if (debug_linux_nat)
3440 fprintf_unfiltered (gdb_stdlog,
3441 "LLW: %s %s, 0, 0 (expect SIGSTOP)\n",
3442 lp->step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3443 target_pid_to_str (lp->ptid));
3445 gdb_assert (lp->resumed);
3447 /* Catch the pending SIGSTOP. */
3448 status = lp->status;
3451 stop_wait_callback (lp, NULL);
3453 /* If the lp->status field isn't empty, we caught another signal
3454 while flushing the SIGSTOP. Return it back to the event
3455 queue of the LWP, as we already have an event to handle. */
3458 if (debug_linux_nat)
3459 fprintf_unfiltered (gdb_stdlog,
3460 "LLW: kill %s, %s\n",
3461 target_pid_to_str (lp->ptid),
3462 status_to_str (lp->status));
3463 kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (lp->status));
3466 lp->status = status;
3469 if (!target_can_async_p ())
3471 /* Causes SIGINT to be passed on to the attached process. */
3475 /* Translate generic target_wait options into waitpid options. */
3476 if (target_options & TARGET_WNOHANG)
3483 lwpid = my_waitpid (pid, &status, options);
3487 gdb_assert (pid == -1 || lwpid == pid);
3489 if (debug_linux_nat)
3491 fprintf_unfiltered (gdb_stdlog,
3492 "LLW: waitpid %ld received %s\n",
3493 (long) lwpid, status_to_str (status));
3496 lp = linux_nat_filter_event (lwpid, status, options);
3498 /* STATUS is now no longer valid, use LP->STATUS instead. */
3502 && ptid_is_pid (ptid)
3503 && ptid_get_pid (lp->ptid) != ptid_get_pid (ptid))
3505 gdb_assert (lp->resumed);
3507 if (debug_linux_nat)
3509 "LWP %ld got an event %06x, leaving pending.\n",
3510 ptid_get_lwp (lp->ptid), lp->status);
3512 if (WIFSTOPPED (lp->status))
3514 if (WSTOPSIG (lp->status) != SIGSTOP)
3516 /* Cancel breakpoint hits. The breakpoint may
3517 be removed before we fetch events from this
3518 process to report to the core. It is best
3519 not to assume the moribund breakpoints
3520 heuristic always handles these cases --- it
3521 could be too many events go through to the
3522 core before this one is handled. All-stop
3523 always cancels breakpoint hits in all
3526 && linux_nat_lp_status_is_event (lp)
3527 && cancel_breakpoint (lp))
3529 /* Throw away the SIGTRAP. */
3532 if (debug_linux_nat)
3534 "LLW: LWP %ld hit a breakpoint while"
3535 " waiting for another process;"
3537 ptid_get_lwp (lp->ptid));
3547 else if (WIFEXITED (lp->status) || WIFSIGNALED (lp->status))
3549 if (debug_linux_nat)
3551 "Process %ld exited while stopping LWPs\n",
3552 ptid_get_lwp (lp->ptid));
3554 /* This was the last lwp in the process. Since
3555 events are serialized to GDB core, and we can't
3556 report this one right now, but GDB core and the
3557 other target layers will want to be notified
3558 about the exit code/signal, leave the status
3559 pending for the next time we're able to report
3562 /* Prevent trying to stop this thread again. We'll
3563 never try to resume it because it has a pending
3567 /* Dead LWP's aren't expected to reported a pending
3571 /* Store the pending event in the waitstatus as
3572 well, because W_EXITCODE(0,0) == 0. */
3573 store_waitstatus (&lp->waitstatus, lp->status);
3587 /* waitpid did return something. Restart over. */
3588 options |= __WCLONE;
3596 /* Alternate between checking cloned and uncloned processes. */
3597 options ^= __WCLONE;
3599 /* And every time we have checked both:
3600 In async mode, return to event loop;
3601 In sync mode, suspend waiting for a SIGCHLD signal. */
3602 if (options & __WCLONE)
3604 if (target_options & TARGET_WNOHANG)
3606 /* No interesting event. */
3607 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3609 if (debug_linux_nat)
3610 fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n");
3612 restore_child_signals_mask (&prev_mask);
3613 return minus_one_ptid;
3616 sigsuspend (&suspend_mask);
3619 else if (target_options & TARGET_WNOHANG)
3621 /* No interesting event for PID yet. */
3622 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3624 if (debug_linux_nat)
3625 fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n");
3627 restore_child_signals_mask (&prev_mask);
3628 return minus_one_ptid;
3631 /* We shouldn't end up here unless we want to try again. */
3632 gdb_assert (lp == NULL);
3635 if (!target_can_async_p ())
3636 clear_sigint_trap ();
3640 status = lp->status;
3643 /* Don't report signals that GDB isn't interested in, such as
3644 signals that are neither printed nor stopped upon. Stopping all
3645 threads can be a bit time-consuming so if we want decent
3646 performance with heavily multi-threaded programs, especially when
3647 they're using a high frequency timer, we'd better avoid it if we
3650 if (WIFSTOPPED (status))
3652 enum target_signal signo = target_signal_from_host (WSTOPSIG (status));
3654 /* When using hardware single-step, we need to report every signal.
3655 Otherwise, signals in pass_mask may be short-circuited. */
3657 && WSTOPSIG (status) && sigismember (&pass_mask, WSTOPSIG (status)))
3659 /* FIMXE: kettenis/2001-06-06: Should we resume all threads
3660 here? It is not clear we should. GDB may not expect
3661 other threads to run. On the other hand, not resuming
3662 newly attached threads may cause an unwanted delay in
3663 getting them running. */
3664 registers_changed ();
3665 linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
3667 if (debug_linux_nat)
3668 fprintf_unfiltered (gdb_stdlog,
3669 "LLW: %s %s, %s (preempt 'handle')\n",
3671 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3672 target_pid_to_str (lp->ptid),
3673 (signo != TARGET_SIGNAL_0
3674 ? strsignal (target_signal_to_host (signo))
3682 /* Only do the below in all-stop, as we currently use SIGINT
3683 to implement target_stop (see linux_nat_stop) in
3685 if (signo == TARGET_SIGNAL_INT && signal_pass_state (signo) == 0)
3687 /* If ^C/BREAK is typed at the tty/console, SIGINT gets
3688 forwarded to the entire process group, that is, all LWPs
3689 will receive it - unless they're using CLONE_THREAD to
3690 share signals. Since we only want to report it once, we
3691 mark it as ignored for all LWPs except this one. */
3692 iterate_over_lwps (pid_to_ptid (ptid_get_pid (ptid)),
3693 set_ignore_sigint, NULL);
3694 lp->ignore_sigint = 0;
3697 maybe_clear_ignore_sigint (lp);
3701 /* This LWP is stopped now. */
3704 if (debug_linux_nat)
3705 fprintf_unfiltered (gdb_stdlog, "LLW: Candidate event %s in %s.\n",
3706 status_to_str (status), target_pid_to_str (lp->ptid));
3710 /* Now stop all other LWP's ... */
3711 iterate_over_lwps (minus_one_ptid, stop_callback, NULL);
3713 /* ... and wait until all of them have reported back that
3714 they're no longer running. */
3715 iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL);
3717 /* If we're not waiting for a specific LWP, choose an event LWP
3718 from among those that have had events. Giving equal priority
3719 to all LWPs that have had events helps prevent
3722 select_event_lwp (ptid, &lp, &status);
3724 /* Now that we've selected our final event LWP, cancel any
3725 breakpoints in other LWPs that have hit a GDB breakpoint.
3726 See the comment in cancel_breakpoints_callback to find out
3728 iterate_over_lwps (minus_one_ptid, cancel_breakpoints_callback, lp);
3730 /* In all-stop, from the core's perspective, all LWPs are now
3731 stopped until a new resume action is sent over. */
3732 iterate_over_lwps (minus_one_ptid, resume_clear_callback, NULL);
3737 if (linux_nat_status_is_event (status))
3739 if (debug_linux_nat)
3740 fprintf_unfiltered (gdb_stdlog,
3741 "LLW: trap ptid is %s.\n",
3742 target_pid_to_str (lp->ptid));
3745 if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE)
3747 *ourstatus = lp->waitstatus;
3748 lp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
3751 store_waitstatus (ourstatus, status);
3753 if (debug_linux_nat)
3754 fprintf_unfiltered (gdb_stdlog, "LLW: exit\n");
3756 restore_child_signals_mask (&prev_mask);
3758 if (ourstatus->kind == TARGET_WAITKIND_EXITED
3759 || ourstatus->kind == TARGET_WAITKIND_SIGNALLED)
3762 lp->core = linux_nat_core_of_thread_1 (lp->ptid);
3767 /* Resume LWPs that are currently stopped without any pending status
3768 to report, but are resumed from the core's perspective. */
3771 resume_stopped_resumed_lwps (struct lwp_info *lp, void *data)
3773 ptid_t *wait_ptid_p = data;
3778 && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE)
3780 gdb_assert (is_executing (lp->ptid));
3782 /* Don't bother if there's a breakpoint at PC that we'd hit
3783 immediately, and we're not waiting for this LWP. */
3784 if (!ptid_match (lp->ptid, *wait_ptid_p))
3786 struct regcache *regcache = get_thread_regcache (lp->ptid);
3787 CORE_ADDR pc = regcache_read_pc (regcache);
3789 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc))
3793 if (debug_linux_nat)
3794 fprintf_unfiltered (gdb_stdlog,
3795 "RSRL: resuming stopped-resumed LWP %s\n",
3796 target_pid_to_str (lp->ptid));
3798 linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
3799 lp->step, TARGET_SIGNAL_0);
3801 memset (&lp->siginfo, 0, sizeof (lp->siginfo));
3802 lp->stopped_by_watchpoint = 0;
3809 linux_nat_wait (struct target_ops *ops,
3810 ptid_t ptid, struct target_waitstatus *ourstatus,
3815 if (debug_linux_nat)
3816 fprintf_unfiltered (gdb_stdlog,
3817 "linux_nat_wait: [%s]\n", target_pid_to_str (ptid));
3819 /* Flush the async file first. */
3820 if (target_can_async_p ())
3821 async_file_flush ();
3823 /* Resume LWPs that are currently stopped without any pending status
3824 to report, but are resumed from the core's perspective. LWPs get
3825 in this state if we find them stopping at a time we're not
3826 interested in reporting the event (target_wait on a
3827 specific_process, for example, see linux_nat_wait_1), and
3828 meanwhile the event became uninteresting. Don't bother resuming
3829 LWPs we're not going to wait for if they'd stop immediately. */
3831 iterate_over_lwps (minus_one_ptid, resume_stopped_resumed_lwps, &ptid);
3833 event_ptid = linux_nat_wait_1 (ops, ptid, ourstatus, target_options);
3835 /* If we requested any event, and something came out, assume there
3836 may be more. If we requested a specific lwp or process, also
3837 assume there may be more. */
3838 if (target_can_async_p ()
3839 && (ourstatus->kind != TARGET_WAITKIND_IGNORE
3840 || !ptid_equal (ptid, minus_one_ptid)))
3843 /* Get ready for the next event. */
3844 if (target_can_async_p ())
3845 target_async (inferior_event_handler, 0);
3851 kill_callback (struct lwp_info *lp, void *data)
3853 /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */
3856 kill (GET_LWP (lp->ptid), SIGKILL);
3857 if (debug_linux_nat)
3858 fprintf_unfiltered (gdb_stdlog,
3859 "KC: kill (SIGKILL) %s, 0, 0 (%s)\n",
3860 target_pid_to_str (lp->ptid),
3861 errno ? safe_strerror (errno) : "OK");
3863 /* Some kernels ignore even SIGKILL for processes under ptrace. */
3866 ptrace (PTRACE_KILL, GET_LWP (lp->ptid), 0, 0);
3867 if (debug_linux_nat)
3868 fprintf_unfiltered (gdb_stdlog,
3869 "KC: PTRACE_KILL %s, 0, 0 (%s)\n",
3870 target_pid_to_str (lp->ptid),
3871 errno ? safe_strerror (errno) : "OK");
3877 kill_wait_callback (struct lwp_info *lp, void *data)
3881 /* We must make sure that there are no pending events (delayed
3882 SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current
3883 program doesn't interfere with any following debugging session. */
3885 /* For cloned processes we must check both with __WCLONE and
3886 without, since the exit status of a cloned process isn't reported
3892 pid = my_waitpid (GET_LWP (lp->ptid), NULL, __WCLONE);
3893 if (pid != (pid_t) -1)
3895 if (debug_linux_nat)
3896 fprintf_unfiltered (gdb_stdlog,
3897 "KWC: wait %s received unknown.\n",
3898 target_pid_to_str (lp->ptid));
3899 /* The Linux kernel sometimes fails to kill a thread
3900 completely after PTRACE_KILL; that goes from the stop
3901 point in do_fork out to the one in
3902 get_signal_to_deliever and waits again. So kill it
3904 kill_callback (lp, NULL);
3907 while (pid == GET_LWP (lp->ptid));
3909 gdb_assert (pid == -1 && errno == ECHILD);
3914 pid = my_waitpid (GET_LWP (lp->ptid), NULL, 0);
3915 if (pid != (pid_t) -1)
3917 if (debug_linux_nat)
3918 fprintf_unfiltered (gdb_stdlog,
3919 "KWC: wait %s received unk.\n",
3920 target_pid_to_str (lp->ptid));
3921 /* See the call to kill_callback above. */
3922 kill_callback (lp, NULL);
3925 while (pid == GET_LWP (lp->ptid));
3927 gdb_assert (pid == -1 && errno == ECHILD);
3932 linux_nat_kill (struct target_ops *ops)
3934 struct target_waitstatus last;
3938 /* If we're stopped while forking and we haven't followed yet,
3939 kill the other task. We need to do this first because the
3940 parent will be sleeping if this is a vfork. */
3942 get_last_target_status (&last_ptid, &last);
3944 if (last.kind == TARGET_WAITKIND_FORKED
3945 || last.kind == TARGET_WAITKIND_VFORKED)
3947 ptrace (PT_KILL, PIDGET (last.value.related_pid), 0, 0);
3951 if (forks_exist_p ())
3952 linux_fork_killall ();
3955 ptid_t ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
3957 /* Stop all threads before killing them, since ptrace requires
3958 that the thread is stopped to sucessfully PTRACE_KILL. */
3959 iterate_over_lwps (ptid, stop_callback, NULL);
3960 /* ... and wait until all of them have reported back that
3961 they're no longer running. */
3962 iterate_over_lwps (ptid, stop_wait_callback, NULL);
3964 /* Kill all LWP's ... */
3965 iterate_over_lwps (ptid, kill_callback, NULL);
3967 /* ... and wait until we've flushed all events. */
3968 iterate_over_lwps (ptid, kill_wait_callback, NULL);
3971 target_mourn_inferior ();
3975 linux_nat_mourn_inferior (struct target_ops *ops)
3977 purge_lwp_list (ptid_get_pid (inferior_ptid));
3979 if (! forks_exist_p ())
3980 /* Normal case, no other forks available. */
3981 linux_ops->to_mourn_inferior (ops);
3983 /* Multi-fork case. The current inferior_ptid has exited, but
3984 there are other viable forks to debug. Delete the exiting
3985 one and context-switch to the first available. */
3986 linux_fork_mourn_inferior ();
3989 /* Convert a native/host siginfo object, into/from the siginfo in the
3990 layout of the inferiors' architecture. */
3993 siginfo_fixup (struct siginfo *siginfo, gdb_byte *inf_siginfo, int direction)
3997 if (linux_nat_siginfo_fixup != NULL)
3998 done = linux_nat_siginfo_fixup (siginfo, inf_siginfo, direction);
4000 /* If there was no callback, or the callback didn't do anything,
4001 then just do a straight memcpy. */
4005 memcpy (siginfo, inf_siginfo, sizeof (struct siginfo));
4007 memcpy (inf_siginfo, siginfo, sizeof (struct siginfo));
4012 linux_xfer_siginfo (struct target_ops *ops, enum target_object object,
4013 const char *annex, gdb_byte *readbuf,
4014 const gdb_byte *writebuf, ULONGEST offset, LONGEST len)
4017 struct siginfo siginfo;
4018 gdb_byte inf_siginfo[sizeof (struct siginfo)];
4020 gdb_assert (object == TARGET_OBJECT_SIGNAL_INFO);
4021 gdb_assert (readbuf || writebuf);
4023 pid = GET_LWP (inferior_ptid);
4025 pid = GET_PID (inferior_ptid);
4027 if (offset > sizeof (siginfo))
4031 ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo);
4035 /* When GDB is built as a 64-bit application, ptrace writes into
4036 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4037 inferior with a 64-bit GDB should look the same as debugging it
4038 with a 32-bit GDB, we need to convert it. GDB core always sees
4039 the converted layout, so any read/write will have to be done
4041 siginfo_fixup (&siginfo, inf_siginfo, 0);
4043 if (offset + len > sizeof (siginfo))
4044 len = sizeof (siginfo) - offset;
4046 if (readbuf != NULL)
4047 memcpy (readbuf, inf_siginfo + offset, len);
4050 memcpy (inf_siginfo + offset, writebuf, len);
4052 /* Convert back to ptrace layout before flushing it out. */
4053 siginfo_fixup (&siginfo, inf_siginfo, 1);
4056 ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo);
4065 linux_nat_xfer_partial (struct target_ops *ops, enum target_object object,
4066 const char *annex, gdb_byte *readbuf,
4067 const gdb_byte *writebuf,
4068 ULONGEST offset, LONGEST len)
4070 struct cleanup *old_chain;
4073 if (object == TARGET_OBJECT_SIGNAL_INFO)
4074 return linux_xfer_siginfo (ops, object, annex, readbuf, writebuf,
4077 /* The target is connected but no live inferior is selected. Pass
4078 this request down to a lower stratum (e.g., the executable
4080 if (object == TARGET_OBJECT_MEMORY && ptid_equal (inferior_ptid, null_ptid))
4083 old_chain = save_inferior_ptid ();
4085 if (is_lwp (inferior_ptid))
4086 inferior_ptid = pid_to_ptid (GET_LWP (inferior_ptid));
4088 xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf,
4091 do_cleanups (old_chain);
4096 linux_thread_alive (ptid_t ptid)
4100 gdb_assert (is_lwp (ptid));
4102 /* Send signal 0 instead of anything ptrace, because ptracing a
4103 running thread errors out claiming that the thread doesn't
4105 err = kill_lwp (GET_LWP (ptid), 0);
4107 if (debug_linux_nat)
4108 fprintf_unfiltered (gdb_stdlog,
4109 "LLTA: KILL(SIG0) %s (%s)\n",
4110 target_pid_to_str (ptid),
4111 err ? safe_strerror (tmp_errno) : "OK");
4120 linux_nat_thread_alive (struct target_ops *ops, ptid_t ptid)
4122 return linux_thread_alive (ptid);
4126 linux_nat_pid_to_str (struct target_ops *ops, ptid_t ptid)
4128 static char buf[64];
4131 && (GET_PID (ptid) != GET_LWP (ptid)
4132 || num_lwps (GET_PID (ptid)) > 1))
4134 snprintf (buf, sizeof (buf), "LWP %ld", GET_LWP (ptid));
4138 return normal_pid_to_str (ptid);
4142 linux_nat_thread_name (struct thread_info *thr)
4144 int pid = ptid_get_pid (thr->ptid);
4145 long lwp = ptid_get_lwp (thr->ptid);
4146 #define FORMAT "/proc/%d/task/%ld/comm"
4147 char buf[sizeof (FORMAT) + 30];
4149 char *result = NULL;
4151 snprintf (buf, sizeof (buf), FORMAT, pid, lwp);
4152 comm_file = fopen (buf, "r");
4155 /* Not exported by the kernel, so we define it here. */
4157 static char line[COMM_LEN + 1];
4159 if (fgets (line, sizeof (line), comm_file))
4161 char *nl = strchr (line, '\n');
4178 /* Accepts an integer PID; Returns a string representing a file that
4179 can be opened to get the symbols for the child process. */
4182 linux_child_pid_to_exec_file (int pid)
4184 char *name1, *name2;
4186 name1 = xmalloc (MAXPATHLEN);
4187 name2 = xmalloc (MAXPATHLEN);
4188 make_cleanup (xfree, name1);
4189 make_cleanup (xfree, name2);
4190 memset (name2, 0, MAXPATHLEN);
4192 sprintf (name1, "/proc/%d/exe", pid);
4193 if (readlink (name1, name2, MAXPATHLEN) > 0)
4199 /* Service function for corefiles and info proc. */
4202 read_mapping (FILE *mapfile,
4207 char *device, long long *inode, char *filename)
4209 int ret = fscanf (mapfile, "%llx-%llx %s %llx %s %llx",
4210 addr, endaddr, permissions, offset, device, inode);
4213 if (ret > 0 && ret != EOF)
4215 /* Eat everything up to EOL for the filename. This will prevent
4216 weird filenames (such as one with embedded whitespace) from
4217 confusing this code. It also makes this code more robust in
4218 respect to annotations the kernel may add after the filename.
4220 Note the filename is used for informational purposes
4222 ret += fscanf (mapfile, "%[^\n]\n", filename);
4225 return (ret != 0 && ret != EOF);
4228 /* Fills the "to_find_memory_regions" target vector. Lists the memory
4229 regions in the inferior for a corefile. */
4232 linux_nat_find_memory_regions (find_memory_region_ftype func, void *obfd)
4234 int pid = PIDGET (inferior_ptid);
4235 char mapsfilename[MAXPATHLEN];
4237 long long addr, endaddr, size, offset, inode;
4238 char permissions[8], device[8], filename[MAXPATHLEN];
4239 int read, write, exec;
4240 struct cleanup *cleanup;
4242 /* Compose the filename for the /proc memory map, and open it. */
4243 sprintf (mapsfilename, "/proc/%d/maps", pid);
4244 if ((mapsfile = fopen (mapsfilename, "r")) == NULL)
4245 error (_("Could not open %s."), mapsfilename);
4246 cleanup = make_cleanup_fclose (mapsfile);
4249 fprintf_filtered (gdb_stdout,
4250 "Reading memory regions from %s\n", mapsfilename);
4252 /* Now iterate until end-of-file. */
4253 while (read_mapping (mapsfile, &addr, &endaddr, &permissions[0],
4254 &offset, &device[0], &inode, &filename[0]))
4256 size = endaddr - addr;
4258 /* Get the segment's permissions. */
4259 read = (strchr (permissions, 'r') != 0);
4260 write = (strchr (permissions, 'w') != 0);
4261 exec = (strchr (permissions, 'x') != 0);
4265 fprintf_filtered (gdb_stdout,
4266 "Save segment, %s bytes at %s (%c%c%c)",
4267 plongest (size), paddress (target_gdbarch, addr),
4269 write ? 'w' : ' ', exec ? 'x' : ' ');
4271 fprintf_filtered (gdb_stdout, " for %s", filename);
4272 fprintf_filtered (gdb_stdout, "\n");
4275 /* Invoke the callback function to create the corefile
4277 func (addr, size, read, write, exec, obfd);
4279 do_cleanups (cleanup);
4284 find_signalled_thread (struct thread_info *info, void *data)
4286 if (info->suspend.stop_signal != TARGET_SIGNAL_0
4287 && ptid_get_pid (info->ptid) == ptid_get_pid (inferior_ptid))
4293 static enum target_signal
4294 find_stop_signal (void)
4296 struct thread_info *info =
4297 iterate_over_threads (find_signalled_thread, NULL);
4300 return info->suspend.stop_signal;
4302 return TARGET_SIGNAL_0;
4305 /* Records the thread's register state for the corefile note
4309 linux_nat_do_thread_registers (bfd *obfd, ptid_t ptid,
4310 char *note_data, int *note_size,
4311 enum target_signal stop_signal)
4313 unsigned long lwp = ptid_get_lwp (ptid);
4314 struct gdbarch *gdbarch = target_gdbarch;
4315 struct regcache *regcache = get_thread_arch_regcache (ptid, gdbarch);
4316 const struct regset *regset;
4318 struct cleanup *old_chain;
4319 struct core_regset_section *sect_list;
4322 old_chain = save_inferior_ptid ();
4323 inferior_ptid = ptid;
4324 target_fetch_registers (regcache, -1);
4325 do_cleanups (old_chain);
4327 core_regset_p = gdbarch_regset_from_core_section_p (gdbarch);
4328 sect_list = gdbarch_core_regset_sections (gdbarch);
4330 /* The loop below uses the new struct core_regset_section, which stores
4331 the supported section names and sizes for the core file. Note that
4332 note PRSTATUS needs to be treated specially. But the other notes are
4333 structurally the same, so they can benefit from the new struct. */
4334 if (core_regset_p && sect_list != NULL)
4335 while (sect_list->sect_name != NULL)
4337 regset = gdbarch_regset_from_core_section (gdbarch,
4338 sect_list->sect_name,
4340 gdb_assert (regset && regset->collect_regset);
4341 gdb_regset = xmalloc (sect_list->size);
4342 regset->collect_regset (regset, regcache, -1,
4343 gdb_regset, sect_list->size);
4345 if (strcmp (sect_list->sect_name, ".reg") == 0)
4346 note_data = (char *) elfcore_write_prstatus
4347 (obfd, note_data, note_size,
4348 lwp, target_signal_to_host (stop_signal),
4351 note_data = (char *) elfcore_write_register_note
4352 (obfd, note_data, note_size,
4353 sect_list->sect_name, gdb_regset,
4359 /* For architectures that does not have the struct core_regset_section
4360 implemented, we use the old method. When all the architectures have
4361 the new support, the code below should be deleted. */
4364 gdb_gregset_t gregs;
4365 gdb_fpregset_t fpregs;
4368 && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg",
4370 != NULL && regset->collect_regset != NULL)
4371 regset->collect_regset (regset, regcache, -1,
4372 &gregs, sizeof (gregs));
4374 fill_gregset (regcache, &gregs, -1);
4376 note_data = (char *) elfcore_write_prstatus
4377 (obfd, note_data, note_size, lwp, target_signal_to_host (stop_signal),
4381 && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg2",
4383 != NULL && regset->collect_regset != NULL)
4384 regset->collect_regset (regset, regcache, -1,
4385 &fpregs, sizeof (fpregs));
4387 fill_fpregset (regcache, &fpregs, -1);
4389 note_data = (char *) elfcore_write_prfpreg (obfd,
4392 &fpregs, sizeof (fpregs));
4398 struct linux_nat_corefile_thread_data
4404 enum target_signal stop_signal;
4407 /* Called by gdbthread.c once per thread. Records the thread's
4408 register state for the corefile note section. */
4411 linux_nat_corefile_thread_callback (struct lwp_info *ti, void *data)
4413 struct linux_nat_corefile_thread_data *args = data;
4415 args->note_data = linux_nat_do_thread_registers (args->obfd,
4425 /* Enumerate spufs IDs for process PID. */
4428 iterate_over_spus (int pid, void (*callback) (void *, int), void *data)
4432 struct dirent *entry;
4434 xsnprintf (path, sizeof path, "/proc/%d/fd", pid);
4435 dir = opendir (path);
4440 while ((entry = readdir (dir)) != NULL)
4446 fd = atoi (entry->d_name);
4450 xsnprintf (path, sizeof path, "/proc/%d/fd/%d", pid, fd);
4451 if (stat (path, &st) != 0)
4453 if (!S_ISDIR (st.st_mode))
4456 if (statfs (path, &stfs) != 0)
4458 if (stfs.f_type != SPUFS_MAGIC)
4461 callback (data, fd);
4467 /* Generate corefile notes for SPU contexts. */
4469 struct linux_spu_corefile_data
4477 linux_spu_corefile_callback (void *data, int fd)
4479 struct linux_spu_corefile_data *args = data;
4482 static const char *spu_files[] =
4504 for (i = 0; i < sizeof (spu_files) / sizeof (spu_files[0]); i++)
4506 char annex[32], note_name[32];
4510 xsnprintf (annex, sizeof annex, "%d/%s", fd, spu_files[i]);
4511 spu_len = target_read_alloc (¤t_target, TARGET_OBJECT_SPU,
4515 xsnprintf (note_name, sizeof note_name, "SPU/%s", annex);
4516 args->note_data = elfcore_write_note (args->obfd, args->note_data,
4517 args->note_size, note_name,
4518 NT_SPU, spu_data, spu_len);
4525 linux_spu_make_corefile_notes (bfd *obfd, char *note_data, int *note_size)
4527 struct linux_spu_corefile_data args;
4530 args.note_data = note_data;
4531 args.note_size = note_size;
4533 iterate_over_spus (PIDGET (inferior_ptid),
4534 linux_spu_corefile_callback, &args);
4536 return args.note_data;
4539 /* Fills the "to_make_corefile_note" target vector. Builds the note
4540 section for a corefile, and returns it in a malloc buffer. */
4543 linux_nat_make_corefile_notes (bfd *obfd, int *note_size)
4545 struct linux_nat_corefile_thread_data thread_args;
4546 /* The variable size must be >= sizeof (prpsinfo_t.pr_fname). */
4547 char fname[16] = { '\0' };
4548 /* The variable size must be >= sizeof (prpsinfo_t.pr_psargs). */
4549 char psargs[80] = { '\0' };
4550 char *note_data = NULL;
4551 ptid_t filter = pid_to_ptid (ptid_get_pid (inferior_ptid));
4555 if (get_exec_file (0))
4557 strncpy (fname, lbasename (get_exec_file (0)), sizeof (fname));
4558 strncpy (psargs, get_exec_file (0), sizeof (psargs));
4559 if (get_inferior_args ())
4562 char *psargs_end = psargs + sizeof (psargs);
4564 /* linux_elfcore_write_prpsinfo () handles zero unterminated
4566 string_end = memchr (psargs, 0, sizeof (psargs));
4567 if (string_end != NULL)
4569 *string_end++ = ' ';
4570 strncpy (string_end, get_inferior_args (),
4571 psargs_end - string_end);
4574 note_data = (char *) elfcore_write_prpsinfo (obfd,
4576 note_size, fname, psargs);
4579 /* Dump information for threads. */
4580 thread_args.obfd = obfd;
4581 thread_args.note_data = note_data;
4582 thread_args.note_size = note_size;
4583 thread_args.num_notes = 0;
4584 thread_args.stop_signal = find_stop_signal ();
4585 iterate_over_lwps (filter, linux_nat_corefile_thread_callback, &thread_args);
4586 gdb_assert (thread_args.num_notes != 0);
4587 note_data = thread_args.note_data;
4589 auxv_len = target_read_alloc (¤t_target, TARGET_OBJECT_AUXV,
4593 note_data = elfcore_write_note (obfd, note_data, note_size,
4594 "CORE", NT_AUXV, auxv, auxv_len);
4598 note_data = linux_spu_make_corefile_notes (obfd, note_data, note_size);
4600 make_cleanup (xfree, note_data);
4604 /* Implement the "info proc" command. */
4607 linux_nat_info_proc_cmd (char *args, int from_tty)
4609 /* A long is used for pid instead of an int to avoid a loss of precision
4610 compiler warning from the output of strtoul. */
4611 long pid = PIDGET (inferior_ptid);
4614 char buffer[MAXPATHLEN];
4615 char fname1[MAXPATHLEN], fname2[MAXPATHLEN];
4627 /* Break up 'args' into an argv array. */
4628 argv = gdb_buildargv (args);
4629 make_cleanup_freeargv (argv);
4631 while (argv != NULL && *argv != NULL)
4633 if (isdigit (argv[0][0]))
4635 pid = strtoul (argv[0], NULL, 10);
4637 else if (strncmp (argv[0], "mappings", strlen (argv[0])) == 0)
4641 else if (strcmp (argv[0], "status") == 0)
4645 else if (strcmp (argv[0], "stat") == 0)
4649 else if (strcmp (argv[0], "cmd") == 0)
4653 else if (strncmp (argv[0], "exe", strlen (argv[0])) == 0)
4657 else if (strcmp (argv[0], "cwd") == 0)
4661 else if (strncmp (argv[0], "all", strlen (argv[0])) == 0)
4667 /* [...] (future options here). */
4672 error (_("No current process: you must name one."));
4674 sprintf (fname1, "/proc/%ld", pid);
4675 if (stat (fname1, &dummy) != 0)
4676 error (_("No /proc directory: '%s'"), fname1);
4678 printf_filtered (_("process %ld\n"), pid);
4679 if (cmdline_f || all)
4681 sprintf (fname1, "/proc/%ld/cmdline", pid);
4682 if ((procfile = fopen (fname1, "r")) != NULL)
4684 struct cleanup *cleanup = make_cleanup_fclose (procfile);
4686 if (fgets (buffer, sizeof (buffer), procfile))
4687 printf_filtered ("cmdline = '%s'\n", buffer);
4689 warning (_("unable to read '%s'"), fname1);
4690 do_cleanups (cleanup);
4693 warning (_("unable to open /proc file '%s'"), fname1);
4697 sprintf (fname1, "/proc/%ld/cwd", pid);
4698 memset (fname2, 0, sizeof (fname2));
4699 if (readlink (fname1, fname2, sizeof (fname2)) > 0)
4700 printf_filtered ("cwd = '%s'\n", fname2);
4702 warning (_("unable to read link '%s'"), fname1);
4706 sprintf (fname1, "/proc/%ld/exe", pid);
4707 memset (fname2, 0, sizeof (fname2));
4708 if (readlink (fname1, fname2, sizeof (fname2)) > 0)
4709 printf_filtered ("exe = '%s'\n", fname2);
4711 warning (_("unable to read link '%s'"), fname1);
4713 if (mappings_f || all)
4715 sprintf (fname1, "/proc/%ld/maps", pid);
4716 if ((procfile = fopen (fname1, "r")) != NULL)
4718 long long addr, endaddr, size, offset, inode;
4719 char permissions[8], device[8], filename[MAXPATHLEN];
4720 struct cleanup *cleanup;
4722 cleanup = make_cleanup_fclose (procfile);
4723 printf_filtered (_("Mapped address spaces:\n\n"));
4724 if (gdbarch_addr_bit (target_gdbarch) == 32)
4726 printf_filtered ("\t%10s %10s %10s %10s %7s\n",
4729 " Size", " Offset", "objfile");
4733 printf_filtered (" %18s %18s %10s %10s %7s\n",
4736 " Size", " Offset", "objfile");
4739 while (read_mapping (procfile, &addr, &endaddr, &permissions[0],
4740 &offset, &device[0], &inode, &filename[0]))
4742 size = endaddr - addr;
4744 /* FIXME: carlton/2003-08-27: Maybe the printf_filtered
4745 calls here (and possibly above) should be abstracted
4746 out into their own functions? Andrew suggests using
4747 a generic local_address_string instead to print out
4748 the addresses; that makes sense to me, too. */
4750 if (gdbarch_addr_bit (target_gdbarch) == 32)
4752 printf_filtered ("\t%#10lx %#10lx %#10x %#10x %7s\n",
4753 (unsigned long) addr, /* FIXME: pr_addr */
4754 (unsigned long) endaddr,
4756 (unsigned int) offset,
4757 filename[0] ? filename : "");
4761 printf_filtered (" %#18lx %#18lx %#10x %#10x %7s\n",
4762 (unsigned long) addr, /* FIXME: pr_addr */
4763 (unsigned long) endaddr,
4765 (unsigned int) offset,
4766 filename[0] ? filename : "");
4770 do_cleanups (cleanup);
4773 warning (_("unable to open /proc file '%s'"), fname1);
4775 if (status_f || all)
4777 sprintf (fname1, "/proc/%ld/status", pid);
4778 if ((procfile = fopen (fname1, "r")) != NULL)
4780 struct cleanup *cleanup = make_cleanup_fclose (procfile);
4782 while (fgets (buffer, sizeof (buffer), procfile) != NULL)
4783 puts_filtered (buffer);
4784 do_cleanups (cleanup);
4787 warning (_("unable to open /proc file '%s'"), fname1);
4791 sprintf (fname1, "/proc/%ld/stat", pid);
4792 if ((procfile = fopen (fname1, "r")) != NULL)
4797 struct cleanup *cleanup = make_cleanup_fclose (procfile);
4799 if (fscanf (procfile, "%d ", &itmp) > 0)
4800 printf_filtered (_("Process: %d\n"), itmp);
4801 if (fscanf (procfile, "(%[^)]) ", &buffer[0]) > 0)
4802 printf_filtered (_("Exec file: %s\n"), buffer);
4803 if (fscanf (procfile, "%c ", &ctmp) > 0)
4804 printf_filtered (_("State: %c\n"), ctmp);
4805 if (fscanf (procfile, "%d ", &itmp) > 0)
4806 printf_filtered (_("Parent process: %d\n"), itmp);
4807 if (fscanf (procfile, "%d ", &itmp) > 0)
4808 printf_filtered (_("Process group: %d\n"), itmp);
4809 if (fscanf (procfile, "%d ", &itmp) > 0)
4810 printf_filtered (_("Session id: %d\n"), itmp);
4811 if (fscanf (procfile, "%d ", &itmp) > 0)
4812 printf_filtered (_("TTY: %d\n"), itmp);
4813 if (fscanf (procfile, "%d ", &itmp) > 0)
4814 printf_filtered (_("TTY owner process group: %d\n"), itmp);
4815 if (fscanf (procfile, "%lu ", <mp) > 0)
4816 printf_filtered (_("Flags: 0x%lx\n"), ltmp);
4817 if (fscanf (procfile, "%lu ", <mp) > 0)
4818 printf_filtered (_("Minor faults (no memory page): %lu\n"),
4819 (unsigned long) ltmp);
4820 if (fscanf (procfile, "%lu ", <mp) > 0)
4821 printf_filtered (_("Minor faults, children: %lu\n"),
4822 (unsigned long) ltmp);
4823 if (fscanf (procfile, "%lu ", <mp) > 0)
4824 printf_filtered (_("Major faults (memory page faults): %lu\n"),
4825 (unsigned long) ltmp);
4826 if (fscanf (procfile, "%lu ", <mp) > 0)
4827 printf_filtered (_("Major faults, children: %lu\n"),
4828 (unsigned long) ltmp);
4829 if (fscanf (procfile, "%ld ", <mp) > 0)
4830 printf_filtered (_("utime: %ld\n"), ltmp);
4831 if (fscanf (procfile, "%ld ", <mp) > 0)
4832 printf_filtered (_("stime: %ld\n"), ltmp);
4833 if (fscanf (procfile, "%ld ", <mp) > 0)
4834 printf_filtered (_("utime, children: %ld\n"), ltmp);
4835 if (fscanf (procfile, "%ld ", <mp) > 0)
4836 printf_filtered (_("stime, children: %ld\n"), ltmp);
4837 if (fscanf (procfile, "%ld ", <mp) > 0)
4838 printf_filtered (_("jiffies remaining in current "
4839 "time slice: %ld\n"), ltmp);
4840 if (fscanf (procfile, "%ld ", <mp) > 0)
4841 printf_filtered (_("'nice' value: %ld\n"), ltmp);
4842 if (fscanf (procfile, "%lu ", <mp) > 0)
4843 printf_filtered (_("jiffies until next timeout: %lu\n"),
4844 (unsigned long) ltmp);
4845 if (fscanf (procfile, "%lu ", <mp) > 0)
4846 printf_filtered (_("jiffies until next SIGALRM: %lu\n"),
4847 (unsigned long) ltmp);
4848 if (fscanf (procfile, "%ld ", <mp) > 0)
4849 printf_filtered (_("start time (jiffies since "
4850 "system boot): %ld\n"), ltmp);
4851 if (fscanf (procfile, "%lu ", <mp) > 0)
4852 printf_filtered (_("Virtual memory size: %lu\n"),
4853 (unsigned long) ltmp);
4854 if (fscanf (procfile, "%lu ", <mp) > 0)
4855 printf_filtered (_("Resident set size: %lu\n"),
4856 (unsigned long) ltmp);
4857 if (fscanf (procfile, "%lu ", <mp) > 0)
4858 printf_filtered (_("rlim: %lu\n"), (unsigned long) ltmp);
4859 if (fscanf (procfile, "%lu ", <mp) > 0)
4860 printf_filtered (_("Start of text: 0x%lx\n"), ltmp);
4861 if (fscanf (procfile, "%lu ", <mp) > 0)
4862 printf_filtered (_("End of text: 0x%lx\n"), ltmp);
4863 if (fscanf (procfile, "%lu ", <mp) > 0)
4864 printf_filtered (_("Start of stack: 0x%lx\n"), ltmp);
4865 #if 0 /* Don't know how architecture-dependent the rest is...
4866 Anyway the signal bitmap info is available from "status". */
4867 if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */
4868 printf_filtered (_("Kernel stack pointer: 0x%lx\n"), ltmp);
4869 if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */
4870 printf_filtered (_("Kernel instr pointer: 0x%lx\n"), ltmp);
4871 if (fscanf (procfile, "%ld ", <mp) > 0)
4872 printf_filtered (_("Pending signals bitmap: 0x%lx\n"), ltmp);
4873 if (fscanf (procfile, "%ld ", <mp) > 0)
4874 printf_filtered (_("Blocked signals bitmap: 0x%lx\n"), ltmp);
4875 if (fscanf (procfile, "%ld ", <mp) > 0)
4876 printf_filtered (_("Ignored signals bitmap: 0x%lx\n"), ltmp);
4877 if (fscanf (procfile, "%ld ", <mp) > 0)
4878 printf_filtered (_("Catched signals bitmap: 0x%lx\n"), ltmp);
4879 if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */
4880 printf_filtered (_("wchan (system call): 0x%lx\n"), ltmp);
4882 do_cleanups (cleanup);
4885 warning (_("unable to open /proc file '%s'"), fname1);
4889 /* Implement the to_xfer_partial interface for memory reads using the /proc
4890 filesystem. Because we can use a single read() call for /proc, this
4891 can be much more efficient than banging away at PTRACE_PEEKTEXT,
4892 but it doesn't support writes. */
4895 linux_proc_xfer_partial (struct target_ops *ops, enum target_object object,
4896 const char *annex, gdb_byte *readbuf,
4897 const gdb_byte *writebuf,
4898 ULONGEST offset, LONGEST len)
4904 if (object != TARGET_OBJECT_MEMORY || !readbuf)
4907 /* Don't bother for one word. */
4908 if (len < 3 * sizeof (long))
4911 /* We could keep this file open and cache it - possibly one per
4912 thread. That requires some juggling, but is even faster. */
4913 sprintf (filename, "/proc/%d/mem", PIDGET (inferior_ptid));
4914 fd = open (filename, O_RDONLY | O_LARGEFILE);
4918 /* If pread64 is available, use it. It's faster if the kernel
4919 supports it (only one syscall), and it's 64-bit safe even on
4920 32-bit platforms (for instance, SPARC debugging a SPARC64
4923 if (pread64 (fd, readbuf, len, offset) != len)
4925 if (lseek (fd, offset, SEEK_SET) == -1 || read (fd, readbuf, len) != len)
4936 /* Enumerate spufs IDs for process PID. */
4938 spu_enumerate_spu_ids (int pid, gdb_byte *buf, ULONGEST offset, LONGEST len)
4940 enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
4942 LONGEST written = 0;
4945 struct dirent *entry;
4947 xsnprintf (path, sizeof path, "/proc/%d/fd", pid);
4948 dir = opendir (path);
4953 while ((entry = readdir (dir)) != NULL)
4959 fd = atoi (entry->d_name);
4963 xsnprintf (path, sizeof path, "/proc/%d/fd/%d", pid, fd);
4964 if (stat (path, &st) != 0)
4966 if (!S_ISDIR (st.st_mode))
4969 if (statfs (path, &stfs) != 0)
4971 if (stfs.f_type != SPUFS_MAGIC)
4974 if (pos >= offset && pos + 4 <= offset + len)
4976 store_unsigned_integer (buf + pos - offset, 4, byte_order, fd);
4986 /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU
4987 object type, using the /proc file system. */
4989 linux_proc_xfer_spu (struct target_ops *ops, enum target_object object,
4990 const char *annex, gdb_byte *readbuf,
4991 const gdb_byte *writebuf,
4992 ULONGEST offset, LONGEST len)
4997 int pid = PIDGET (inferior_ptid);
5004 return spu_enumerate_spu_ids (pid, readbuf, offset, len);
5007 xsnprintf (buf, sizeof buf, "/proc/%d/fd/%s", pid, annex);
5008 fd = open (buf, writebuf? O_WRONLY : O_RDONLY);
5013 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
5020 ret = write (fd, writebuf, (size_t) len);
5022 ret = read (fd, readbuf, (size_t) len);
5029 /* Parse LINE as a signal set and add its set bits to SIGS. */
5032 add_line_to_sigset (const char *line, sigset_t *sigs)
5034 int len = strlen (line) - 1;
5038 if (line[len] != '\n')
5039 error (_("Could not parse signal set: %s"), line);
5047 if (*p >= '0' && *p <= '9')
5049 else if (*p >= 'a' && *p <= 'f')
5050 digit = *p - 'a' + 10;
5052 error (_("Could not parse signal set: %s"), line);
5057 sigaddset (sigs, signum + 1);
5059 sigaddset (sigs, signum + 2);
5061 sigaddset (sigs, signum + 3);
5063 sigaddset (sigs, signum + 4);
5069 /* Find process PID's pending signals from /proc/pid/status and set
5073 linux_proc_pending_signals (int pid, sigset_t *pending,
5074 sigset_t *blocked, sigset_t *ignored)
5077 char buffer[MAXPATHLEN], fname[MAXPATHLEN];
5078 struct cleanup *cleanup;
5080 sigemptyset (pending);
5081 sigemptyset (blocked);
5082 sigemptyset (ignored);
5083 sprintf (fname, "/proc/%d/status", pid);
5084 procfile = fopen (fname, "r");
5085 if (procfile == NULL)
5086 error (_("Could not open %s"), fname);
5087 cleanup = make_cleanup_fclose (procfile);
5089 while (fgets (buffer, MAXPATHLEN, procfile) != NULL)
5091 /* Normal queued signals are on the SigPnd line in the status
5092 file. However, 2.6 kernels also have a "shared" pending
5093 queue for delivering signals to a thread group, so check for
5096 Unfortunately some Red Hat kernels include the shared pending
5097 queue but not the ShdPnd status field. */
5099 if (strncmp (buffer, "SigPnd:\t", 8) == 0)
5100 add_line_to_sigset (buffer + 8, pending);
5101 else if (strncmp (buffer, "ShdPnd:\t", 8) == 0)
5102 add_line_to_sigset (buffer + 8, pending);
5103 else if (strncmp (buffer, "SigBlk:\t", 8) == 0)
5104 add_line_to_sigset (buffer + 8, blocked);
5105 else if (strncmp (buffer, "SigIgn:\t", 8) == 0)
5106 add_line_to_sigset (buffer + 8, ignored);
5109 do_cleanups (cleanup);
5113 linux_nat_xfer_osdata (struct target_ops *ops, enum target_object object,
5114 const char *annex, gdb_byte *readbuf,
5115 const gdb_byte *writebuf, ULONGEST offset, LONGEST len)
5117 /* We make the process list snapshot when the object starts to be
5119 static const char *buf;
5120 static LONGEST len_avail = -1;
5121 static struct obstack obstack;
5125 gdb_assert (object == TARGET_OBJECT_OSDATA);
5131 if (len_avail != -1 && len_avail != 0)
5132 obstack_free (&obstack, NULL);
5135 obstack_init (&obstack);
5136 obstack_grow_str (&obstack, "<osdata type=\"types\">\n");
5138 obstack_xml_printf (&obstack,
5140 "<column name=\"Type\">processes</column>"
5141 "<column name=\"Description\">"
5142 "Listing of all processes</column>"
5145 obstack_grow_str0 (&obstack, "</osdata>\n");
5146 buf = obstack_finish (&obstack);
5147 len_avail = strlen (buf);
5150 if (offset >= len_avail)
5152 /* Done. Get rid of the obstack. */
5153 obstack_free (&obstack, NULL);
5159 if (len > len_avail - offset)
5160 len = len_avail - offset;
5161 memcpy (readbuf, buf + offset, len);
5166 if (strcmp (annex, "processes") != 0)
5169 gdb_assert (readbuf && !writebuf);
5173 if (len_avail != -1 && len_avail != 0)
5174 obstack_free (&obstack, NULL);
5177 obstack_init (&obstack);
5178 obstack_grow_str (&obstack, "<osdata type=\"processes\">\n");
5180 dirp = opendir ("/proc");
5185 while ((dp = readdir (dirp)) != NULL)
5187 struct stat statbuf;
5188 char procentry[sizeof ("/proc/4294967295")];
5190 if (!isdigit (dp->d_name[0])
5191 || NAMELEN (dp) > sizeof ("4294967295") - 1)
5194 sprintf (procentry, "/proc/%s", dp->d_name);
5195 if (stat (procentry, &statbuf) == 0
5196 && S_ISDIR (statbuf.st_mode))
5200 char cmd[MAXPATHLEN + 1];
5201 struct passwd *entry;
5203 pathname = xstrprintf ("/proc/%s/cmdline", dp->d_name);
5204 entry = getpwuid (statbuf.st_uid);
5206 if ((f = fopen (pathname, "r")) != NULL)
5208 size_t length = fread (cmd, 1, sizeof (cmd) - 1, f);
5214 for (i = 0; i < length; i++)
5219 obstack_xml_printf (
5222 "<column name=\"pid\">%s</column>"
5223 "<column name=\"user\">%s</column>"
5224 "<column name=\"command\">%s</column>"
5227 entry ? entry->pw_name : "?",
5240 obstack_grow_str0 (&obstack, "</osdata>\n");
5241 buf = obstack_finish (&obstack);
5242 len_avail = strlen (buf);
5245 if (offset >= len_avail)
5247 /* Done. Get rid of the obstack. */
5248 obstack_free (&obstack, NULL);
5254 if (len > len_avail - offset)
5255 len = len_avail - offset;
5256 memcpy (readbuf, buf + offset, len);
5262 linux_xfer_partial (struct target_ops *ops, enum target_object object,
5263 const char *annex, gdb_byte *readbuf,
5264 const gdb_byte *writebuf, ULONGEST offset, LONGEST len)
5268 if (object == TARGET_OBJECT_AUXV)
5269 return memory_xfer_auxv (ops, object, annex, readbuf, writebuf,
5272 if (object == TARGET_OBJECT_OSDATA)
5273 return linux_nat_xfer_osdata (ops, object, annex, readbuf, writebuf,
5276 if (object == TARGET_OBJECT_SPU)
5277 return linux_proc_xfer_spu (ops, object, annex, readbuf, writebuf,
5280 /* GDB calculates all the addresses in possibly larget width of the address.
5281 Address width needs to be masked before its final use - either by
5282 linux_proc_xfer_partial or inf_ptrace_xfer_partial.
5284 Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */
5286 if (object == TARGET_OBJECT_MEMORY)
5288 int addr_bit = gdbarch_addr_bit (target_gdbarch);
5290 if (addr_bit < (sizeof (ULONGEST) * HOST_CHAR_BIT))
5291 offset &= ((ULONGEST) 1 << addr_bit) - 1;
5294 xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf,
5299 return super_xfer_partial (ops, object, annex, readbuf, writebuf,
5303 /* Create a prototype generic GNU/Linux target. The client can override
5304 it with local methods. */
5307 linux_target_install_ops (struct target_ops *t)
5309 t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint;
5310 t->to_remove_fork_catchpoint = linux_child_remove_fork_catchpoint;
5311 t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint;
5312 t->to_remove_vfork_catchpoint = linux_child_remove_vfork_catchpoint;
5313 t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint;
5314 t->to_remove_exec_catchpoint = linux_child_remove_exec_catchpoint;
5315 t->to_set_syscall_catchpoint = linux_child_set_syscall_catchpoint;
5316 t->to_pid_to_exec_file = linux_child_pid_to_exec_file;
5317 t->to_post_startup_inferior = linux_child_post_startup_inferior;
5318 t->to_post_attach = linux_child_post_attach;
5319 t->to_follow_fork = linux_child_follow_fork;
5320 t->to_find_memory_regions = linux_nat_find_memory_regions;
5321 t->to_make_corefile_notes = linux_nat_make_corefile_notes;
5323 super_xfer_partial = t->to_xfer_partial;
5324 t->to_xfer_partial = linux_xfer_partial;
5330 struct target_ops *t;
5332 t = inf_ptrace_target ();
5333 linux_target_install_ops (t);
5339 linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int))
5341 struct target_ops *t;
5343 t = inf_ptrace_trad_target (register_u_offset);
5344 linux_target_install_ops (t);
5349 /* target_is_async_p implementation. */
5352 linux_nat_is_async_p (void)
5354 /* NOTE: palves 2008-03-21: We're only async when the user requests
5355 it explicitly with the "set target-async" command.
5356 Someday, linux will always be async. */
5357 return target_async_permitted;
5360 /* target_can_async_p implementation. */
5363 linux_nat_can_async_p (void)
5365 /* NOTE: palves 2008-03-21: We're only async when the user requests
5366 it explicitly with the "set target-async" command.
5367 Someday, linux will always be async. */
5368 return target_async_permitted;
5372 linux_nat_supports_non_stop (void)
5377 /* True if we want to support multi-process. To be removed when GDB
5378 supports multi-exec. */
5380 int linux_multi_process = 1;
5383 linux_nat_supports_multi_process (void)
5385 return linux_multi_process;
5388 static int async_terminal_is_ours = 1;
5390 /* target_terminal_inferior implementation. */
5393 linux_nat_terminal_inferior (void)
5395 if (!target_is_async_p ())
5397 /* Async mode is disabled. */
5398 terminal_inferior ();
5402 terminal_inferior ();
5404 /* Calls to target_terminal_*() are meant to be idempotent. */
5405 if (!async_terminal_is_ours)
5408 delete_file_handler (input_fd);
5409 async_terminal_is_ours = 0;
5413 /* target_terminal_ours implementation. */
5416 linux_nat_terminal_ours (void)
5418 if (!target_is_async_p ())
5420 /* Async mode is disabled. */
5425 /* GDB should never give the terminal to the inferior if the
5426 inferior is running in the background (run&, continue&, etc.),
5427 but claiming it sure should. */
5430 if (async_terminal_is_ours)
5433 clear_sigint_trap ();
5434 add_file_handler (input_fd, stdin_event_handler, 0);
5435 async_terminal_is_ours = 1;
5438 static void (*async_client_callback) (enum inferior_event_type event_type,
5440 static void *async_client_context;
5442 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5443 so we notice when any child changes state, and notify the
5444 event-loop; it allows us to use sigsuspend in linux_nat_wait_1
5445 above to wait for the arrival of a SIGCHLD. */
5448 sigchld_handler (int signo)
5450 int old_errno = errno;
5452 if (debug_linux_nat)
5453 ui_file_write_async_safe (gdb_stdlog,
5454 "sigchld\n", sizeof ("sigchld\n") - 1);
5456 if (signo == SIGCHLD
5457 && linux_nat_event_pipe[0] != -1)
5458 async_file_mark (); /* Let the event loop know that there are
5459 events to handle. */
5464 /* Callback registered with the target events file descriptor. */
5467 handle_target_event (int error, gdb_client_data client_data)
5469 (*async_client_callback) (INF_REG_EVENT, async_client_context);
5472 /* Create/destroy the target events pipe. Returns previous state. */
5475 linux_async_pipe (int enable)
5477 int previous = (linux_nat_event_pipe[0] != -1);
5479 if (previous != enable)
5483 block_child_signals (&prev_mask);
5487 if (pipe (linux_nat_event_pipe) == -1)
5488 internal_error (__FILE__, __LINE__,
5489 "creating event pipe failed.");
5491 fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK);
5492 fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK);
5496 close (linux_nat_event_pipe[0]);
5497 close (linux_nat_event_pipe[1]);
5498 linux_nat_event_pipe[0] = -1;
5499 linux_nat_event_pipe[1] = -1;
5502 restore_child_signals_mask (&prev_mask);
5508 /* target_async implementation. */
5511 linux_nat_async (void (*callback) (enum inferior_event_type event_type,
5512 void *context), void *context)
5514 if (callback != NULL)
5516 async_client_callback = callback;
5517 async_client_context = context;
5518 if (!linux_async_pipe (1))
5520 add_file_handler (linux_nat_event_pipe[0],
5521 handle_target_event, NULL);
5522 /* There may be pending events to handle. Tell the event loop
5529 async_client_callback = callback;
5530 async_client_context = context;
5531 delete_file_handler (linux_nat_event_pipe[0]);
5532 linux_async_pipe (0);
5537 /* Stop an LWP, and push a TARGET_SIGNAL_0 stop status if no other
5541 linux_nat_stop_lwp (struct lwp_info *lwp, void *data)
5545 ptid_t ptid = lwp->ptid;
5547 if (debug_linux_nat)
5548 fprintf_unfiltered (gdb_stdlog,
5549 "LNSL: running -> suspending %s\n",
5550 target_pid_to_str (lwp->ptid));
5553 stop_callback (lwp, NULL);
5554 stop_wait_callback (lwp, NULL);
5556 /* If the lwp exits while we try to stop it, there's nothing
5558 lwp = find_lwp_pid (ptid);
5562 /* If we didn't collect any signal other than SIGSTOP while
5563 stopping the LWP, push a SIGNAL_0 event. In either case, the
5564 event-loop will end up calling target_wait which will collect
5566 if (lwp->status == 0)
5567 lwp->status = W_STOPCODE (0);
5572 /* Already known to be stopped; do nothing. */
5574 if (debug_linux_nat)
5576 if (find_thread_ptid (lwp->ptid)->stop_requested)
5577 fprintf_unfiltered (gdb_stdlog,
5578 "LNSL: already stopped/stop_requested %s\n",
5579 target_pid_to_str (lwp->ptid));
5581 fprintf_unfiltered (gdb_stdlog,
5582 "LNSL: already stopped/no "
5583 "stop_requested yet %s\n",
5584 target_pid_to_str (lwp->ptid));
5591 linux_nat_stop (ptid_t ptid)
5594 iterate_over_lwps (ptid, linux_nat_stop_lwp, NULL);
5596 linux_ops->to_stop (ptid);
5600 linux_nat_close (int quitting)
5602 /* Unregister from the event loop. */
5603 if (target_is_async_p ())
5604 target_async (NULL, 0);
5606 if (linux_ops->to_close)
5607 linux_ops->to_close (quitting);
5610 /* When requests are passed down from the linux-nat layer to the
5611 single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are
5612 used. The address space pointer is stored in the inferior object,
5613 but the common code that is passed such ptid can't tell whether
5614 lwpid is a "main" process id or not (it assumes so). We reverse
5615 look up the "main" process id from the lwp here. */
5617 struct address_space *
5618 linux_nat_thread_address_space (struct target_ops *t, ptid_t ptid)
5620 struct lwp_info *lwp;
5621 struct inferior *inf;
5624 pid = GET_LWP (ptid);
5625 if (GET_LWP (ptid) == 0)
5627 /* An (lwpid,0,0) ptid. Look up the lwp object to get at the
5629 lwp = find_lwp_pid (ptid);
5630 pid = GET_PID (lwp->ptid);
5634 /* A (pid,lwpid,0) ptid. */
5635 pid = GET_PID (ptid);
5638 inf = find_inferior_pid (pid);
5639 gdb_assert (inf != NULL);
5644 linux_nat_core_of_thread_1 (ptid_t ptid)
5646 struct cleanup *back_to;
5649 char *content = NULL;
5652 int content_read = 0;
5656 filename = xstrprintf ("/proc/%d/task/%ld/stat",
5657 GET_PID (ptid), GET_LWP (ptid));
5658 back_to = make_cleanup (xfree, filename);
5660 f = fopen (filename, "r");
5663 do_cleanups (back_to);
5667 make_cleanup_fclose (f);
5673 content = xrealloc (content, content_read + 1024);
5674 n = fread (content + content_read, 1, 1024, f);
5678 content[content_read] = '\0';
5683 make_cleanup (xfree, content);
5685 p = strchr (content, '(');
5689 p = strchr (p, ')');
5693 /* If the first field after program name has index 0, then core number is
5694 the field with index 36. There's no constant for that anywhere. */
5696 p = strtok_r (p, " ", &ts);
5697 for (i = 0; p != NULL && i != 36; ++i)
5698 p = strtok_r (NULL, " ", &ts);
5700 if (p == NULL || sscanf (p, "%d", &core) == 0)
5703 do_cleanups (back_to);
5708 /* Return the cached value of the processor core for thread PTID. */
5711 linux_nat_core_of_thread (struct target_ops *ops, ptid_t ptid)
5713 struct lwp_info *info = find_lwp_pid (ptid);
5721 linux_nat_add_target (struct target_ops *t)
5723 /* Save the provided single-threaded target. We save this in a separate
5724 variable because another target we've inherited from (e.g. inf-ptrace)
5725 may have saved a pointer to T; we want to use it for the final
5726 process stratum target. */
5727 linux_ops_saved = *t;
5728 linux_ops = &linux_ops_saved;
5730 /* Override some methods for multithreading. */
5731 t->to_create_inferior = linux_nat_create_inferior;
5732 t->to_attach = linux_nat_attach;
5733 t->to_detach = linux_nat_detach;
5734 t->to_resume = linux_nat_resume;
5735 t->to_wait = linux_nat_wait;
5736 t->to_pass_signals = linux_nat_pass_signals;
5737 t->to_xfer_partial = linux_nat_xfer_partial;
5738 t->to_kill = linux_nat_kill;
5739 t->to_mourn_inferior = linux_nat_mourn_inferior;
5740 t->to_thread_alive = linux_nat_thread_alive;
5741 t->to_pid_to_str = linux_nat_pid_to_str;
5742 t->to_thread_name = linux_nat_thread_name;
5743 t->to_has_thread_control = tc_schedlock;
5744 t->to_thread_address_space = linux_nat_thread_address_space;
5745 t->to_stopped_by_watchpoint = linux_nat_stopped_by_watchpoint;
5746 t->to_stopped_data_address = linux_nat_stopped_data_address;
5748 t->to_can_async_p = linux_nat_can_async_p;
5749 t->to_is_async_p = linux_nat_is_async_p;
5750 t->to_supports_non_stop = linux_nat_supports_non_stop;
5751 t->to_async = linux_nat_async;
5752 t->to_terminal_inferior = linux_nat_terminal_inferior;
5753 t->to_terminal_ours = linux_nat_terminal_ours;
5754 t->to_close = linux_nat_close;
5756 /* Methods for non-stop support. */
5757 t->to_stop = linux_nat_stop;
5759 t->to_supports_multi_process = linux_nat_supports_multi_process;
5761 t->to_core_of_thread = linux_nat_core_of_thread;
5763 /* We don't change the stratum; this target will sit at
5764 process_stratum and thread_db will set at thread_stratum. This
5765 is a little strange, since this is a multi-threaded-capable
5766 target, but we want to be on the stack below thread_db, and we
5767 also want to be used for single-threaded processes. */
5772 /* Register a method to call whenever a new thread is attached. */
5774 linux_nat_set_new_thread (struct target_ops *t, void (*new_thread) (ptid_t))
5776 /* Save the pointer. We only support a single registered instance
5777 of the GNU/Linux native target, so we do not need to map this to
5779 linux_nat_new_thread = new_thread;
5782 /* Register a method that converts a siginfo object between the layout
5783 that ptrace returns, and the layout in the architecture of the
5786 linux_nat_set_siginfo_fixup (struct target_ops *t,
5787 int (*siginfo_fixup) (struct siginfo *,
5791 /* Save the pointer. */
5792 linux_nat_siginfo_fixup = siginfo_fixup;
5795 /* Return the saved siginfo associated with PTID. */
5797 linux_nat_get_siginfo (ptid_t ptid)
5799 struct lwp_info *lp = find_lwp_pid (ptid);
5801 gdb_assert (lp != NULL);
5803 return &lp->siginfo;
5806 /* Provide a prototype to silence -Wmissing-prototypes. */
5807 extern initialize_file_ftype _initialize_linux_nat;
5810 _initialize_linux_nat (void)
5812 add_info ("proc", linux_nat_info_proc_cmd, _("\
5813 Show /proc process information about any running process.\n\
5814 Specify any process id, or use the program being debugged by default.\n\
5815 Specify any of the following keywords for detailed info:\n\
5816 mappings -- list of mapped memory regions.\n\
5817 stat -- list a bunch of random process info.\n\
5818 status -- list a different bunch of random process info.\n\
5819 all -- list all available /proc info."));
5821 add_setshow_zinteger_cmd ("lin-lwp", class_maintenance,
5822 &debug_linux_nat, _("\
5823 Set debugging of GNU/Linux lwp module."), _("\
5824 Show debugging of GNU/Linux lwp module."), _("\
5825 Enables printf debugging output."),
5827 show_debug_linux_nat,
5828 &setdebuglist, &showdebuglist);
5830 /* Save this mask as the default. */
5831 sigprocmask (SIG_SETMASK, NULL, &normal_mask);
5833 /* Install a SIGCHLD handler. */
5834 sigchld_action.sa_handler = sigchld_handler;
5835 sigemptyset (&sigchld_action.sa_mask);
5836 sigchld_action.sa_flags = SA_RESTART;
5838 /* Make it the default. */
5839 sigaction (SIGCHLD, &sigchld_action, NULL);
5841 /* Make sure we don't block SIGCHLD during a sigsuspend. */
5842 sigprocmask (SIG_SETMASK, NULL, &suspend_mask);
5843 sigdelset (&suspend_mask, SIGCHLD);
5845 sigemptyset (&blocked_mask);
5847 add_setshow_boolean_cmd ("disable-randomization", class_support,
5848 &disable_randomization, _("\
5849 Set disabling of debuggee's virtual address space randomization."), _("\
5850 Show disabling of debuggee's virtual address space randomization."), _("\
5851 When this mode is on (which is the default), randomization of the virtual\n\
5852 address space is disabled. Standalone programs run with the randomization\n\
5853 enabled by default on some platforms."),
5854 &set_disable_randomization,
5855 &show_disable_randomization,
5856 &setlist, &showlist);
5860 /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to
5861 the GNU/Linux Threads library and therefore doesn't really belong
5864 /* Read variable NAME in the target and return its value if found.
5865 Otherwise return zero. It is assumed that the type of the variable
5869 get_signo (const char *name)
5871 struct minimal_symbol *ms;
5874 ms = lookup_minimal_symbol (name, NULL, NULL);
5878 if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo,
5879 sizeof (signo)) != 0)
5885 /* Return the set of signals used by the threads library in *SET. */
5888 lin_thread_get_thread_signals (sigset_t *set)
5890 struct sigaction action;
5891 int restart, cancel;
5893 sigemptyset (&blocked_mask);
5896 restart = get_signo ("__pthread_sig_restart");
5897 cancel = get_signo ("__pthread_sig_cancel");
5899 /* LinuxThreads normally uses the first two RT signals, but in some legacy
5900 cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does
5901 not provide any way for the debugger to query the signal numbers -
5902 fortunately they don't change! */
5905 restart = __SIGRTMIN;
5908 cancel = __SIGRTMIN + 1;
5910 sigaddset (set, restart);
5911 sigaddset (set, cancel);
5913 /* The GNU/Linux Threads library makes terminating threads send a
5914 special "cancel" signal instead of SIGCHLD. Make sure we catch
5915 those (to prevent them from terminating GDB itself, which is
5916 likely to be their default action) and treat them the same way as
5919 action.sa_handler = sigchld_handler;
5920 sigemptyset (&action.sa_mask);
5921 action.sa_flags = SA_RESTART;
5922 sigaction (cancel, &action, NULL);
5924 /* We block the "cancel" signal throughout this code ... */
5925 sigaddset (&blocked_mask, cancel);
5926 sigprocmask (SIG_BLOCK, &blocked_mask, NULL);
5928 /* ... except during a sigsuspend. */
5929 sigdelset (&suspend_mask, cancel);