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-procfs.h"
35 #include "linux-fork.h"
36 #include "gdbthread.h"
40 #include "inf-ptrace.h"
42 #include <sys/param.h> /* for MAXPATHLEN */
43 #include <sys/procfs.h> /* for elf_gregset etc. */
44 #include "elf-bfd.h" /* for elfcore_write_* */
45 #include "gregset.h" /* for gregset */
46 #include "gdbcore.h" /* for get_exec_file */
47 #include <ctype.h> /* for isdigit */
48 #include "gdbthread.h" /* for struct thread_info etc. */
49 #include "gdb_stat.h" /* for struct stat */
50 #include <fcntl.h> /* for O_RDONLY */
52 #include "event-loop.h"
53 #include "event-top.h"
55 #include <sys/types.h>
56 #include "gdb_dirent.h"
57 #include "xml-support.h"
61 #include "linux-osdata.h"
64 #define SPUFS_MAGIC 0x23c9b64e
67 #ifdef HAVE_PERSONALITY
68 # include <sys/personality.h>
69 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
70 # define ADDR_NO_RANDOMIZE 0x0040000
72 #endif /* HAVE_PERSONALITY */
74 /* This comment documents high-level logic of this file.
76 Waiting for events in sync mode
77 ===============================
79 When waiting for an event in a specific thread, we just use waitpid, passing
80 the specific pid, and not passing WNOHANG.
82 When waiting for an event in all threads, waitpid is not quite good. Prior to
83 version 2.4, Linux can either wait for event in main thread, or in secondary
84 threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might
85 miss an event. The solution is to use non-blocking waitpid, together with
86 sigsuspend. First, we use non-blocking waitpid to get an event in the main
87 process, if any. Second, we use non-blocking waitpid with the __WCLONED
88 flag to check for events in cloned processes. If nothing is found, we use
89 sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something
90 happened to a child process -- and SIGCHLD will be delivered both for events
91 in main debugged process and in cloned processes. As soon as we know there's
92 an event, we get back to calling nonblocking waitpid with and without
95 Note that SIGCHLD should be blocked between waitpid and sigsuspend calls,
96 so that we don't miss a signal. If SIGCHLD arrives in between, when it's
97 blocked, the signal becomes pending and sigsuspend immediately
98 notices it and returns.
100 Waiting for events in async mode
101 ================================
103 In async mode, GDB should always be ready to handle both user input
104 and target events, so neither blocking waitpid nor sigsuspend are
105 viable options. Instead, we should asynchronously notify the GDB main
106 event loop whenever there's an unprocessed event from the target. We
107 detect asynchronous target events by handling SIGCHLD signals. To
108 notify the event loop about target events, the self-pipe trick is used
109 --- a pipe is registered as waitable event source in the event loop,
110 the event loop select/poll's on the read end of this pipe (as well on
111 other event sources, e.g., stdin), and the SIGCHLD handler writes a
112 byte to this pipe. This is more portable than relying on
113 pselect/ppoll, since on kernels that lack those syscalls, libc
114 emulates them with select/poll+sigprocmask, and that is racy
115 (a.k.a. plain broken).
117 Obviously, if we fail to notify the event loop if there's a target
118 event, it's bad. OTOH, if we notify the event loop when there's no
119 event from the target, linux_nat_wait will detect that there's no real
120 event to report, and return event of type TARGET_WAITKIND_IGNORE.
121 This is mostly harmless, but it will waste time and is better avoided.
123 The main design point is that every time GDB is outside linux-nat.c,
124 we have a SIGCHLD handler installed that is called when something
125 happens to the target and notifies the GDB event loop. Whenever GDB
126 core decides to handle the event, and calls into linux-nat.c, we
127 process things as in sync mode, except that the we never block in
130 While processing an event, we may end up momentarily blocked in
131 waitpid calls. Those waitpid calls, while blocking, are guarantied to
132 return quickly. E.g., in all-stop mode, before reporting to the core
133 that an LWP hit a breakpoint, all LWPs are stopped by sending them
134 SIGSTOP, and synchronously waiting for the SIGSTOP to be reported.
135 Note that this is different from blocking indefinitely waiting for the
136 next event --- here, we're already handling an event.
141 We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another
142 signal is not entirely significant; we just need for a signal to be delivered,
143 so that we can intercept it. SIGSTOP's advantage is that it can not be
144 blocked. A disadvantage is that it is not a real-time signal, so it can only
145 be queued once; we do not keep track of other sources of SIGSTOP.
147 Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't
148 use them, because they have special behavior when the signal is generated -
149 not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL
150 kills the entire thread group.
152 A delivered SIGSTOP would stop the entire thread group, not just the thread we
153 tkill'd. But we never let the SIGSTOP be delivered; we always intercept and
154 cancel it (by PTRACE_CONT without passing SIGSTOP).
156 We could use a real-time signal instead. This would solve those problems; we
157 could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB.
158 But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH
159 generates it, and there are races with trying to find a signal that is not
163 #define O_LARGEFILE 0
166 /* Unlike other extended result codes, WSTOPSIG (status) on
167 PTRACE_O_TRACESYSGOOD syscall events doesn't return SIGTRAP, but
168 instead SIGTRAP with bit 7 set. */
169 #define SYSCALL_SIGTRAP (SIGTRAP | 0x80)
171 /* The single-threaded native GNU/Linux target_ops. We save a pointer for
172 the use of the multi-threaded target. */
173 static struct target_ops
*linux_ops
;
174 static struct target_ops linux_ops_saved
;
176 /* The method to call, if any, when a new thread is attached. */
177 static void (*linux_nat_new_thread
) (ptid_t
);
179 /* The method to call, if any, when the siginfo object needs to be
180 converted between the layout returned by ptrace, and the layout in
181 the architecture of the inferior. */
182 static int (*linux_nat_siginfo_fixup
) (struct siginfo
*,
186 /* The saved to_xfer_partial method, inherited from inf-ptrace.c.
187 Called by our to_xfer_partial. */
188 static LONGEST (*super_xfer_partial
) (struct target_ops
*,
190 const char *, gdb_byte
*,
194 static int debug_linux_nat
;
196 show_debug_linux_nat (struct ui_file
*file
, int from_tty
,
197 struct cmd_list_element
*c
, const char *value
)
199 fprintf_filtered (file
, _("Debugging of GNU/Linux lwp module is %s.\n"),
203 struct simple_pid_list
207 struct simple_pid_list
*next
;
209 struct simple_pid_list
*stopped_pids
;
211 /* This variable is a tri-state flag: -1 for unknown, 0 if PTRACE_O_TRACEFORK
212 can not be used, 1 if it can. */
214 static int linux_supports_tracefork_flag
= -1;
216 /* This variable is a tri-state flag: -1 for unknown, 0 if
217 PTRACE_O_TRACESYSGOOD can not be used, 1 if it can. */
219 static int linux_supports_tracesysgood_flag
= -1;
221 /* If we have PTRACE_O_TRACEFORK, this flag indicates whether we also have
222 PTRACE_O_TRACEVFORKDONE. */
224 static int linux_supports_tracevforkdone_flag
= -1;
226 /* Stores the current used ptrace() options. */
227 static int current_ptrace_options
= 0;
229 /* Async mode support. */
231 /* The read/write ends of the pipe registered as waitable file in the
233 static int linux_nat_event_pipe
[2] = { -1, -1 };
235 /* Flush the event pipe. */
238 async_file_flush (void)
245 ret
= read (linux_nat_event_pipe
[0], &buf
, 1);
247 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
250 /* Put something (anything, doesn't matter what, or how much) in event
251 pipe, so that the select/poll in the event-loop realizes we have
252 something to process. */
255 async_file_mark (void)
259 /* It doesn't really matter what the pipe contains, as long we end
260 up with something in it. Might as well flush the previous
266 ret
= write (linux_nat_event_pipe
[1], "+", 1);
268 while (ret
== -1 && errno
== EINTR
);
270 /* Ignore EAGAIN. If the pipe is full, the event loop will already
271 be awakened anyway. */
274 static void linux_nat_async (void (*callback
)
275 (enum inferior_event_type event_type
,
278 static int kill_lwp (int lwpid
, int signo
);
280 static int stop_callback (struct lwp_info
*lp
, void *data
);
282 static void block_child_signals (sigset_t
*prev_mask
);
283 static void restore_child_signals_mask (sigset_t
*prev_mask
);
286 static struct lwp_info
*add_lwp (ptid_t ptid
);
287 static void purge_lwp_list (int pid
);
288 static struct lwp_info
*find_lwp_pid (ptid_t ptid
);
291 /* Trivial list manipulation functions to keep track of a list of
292 new stopped processes. */
294 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
296 struct simple_pid_list
*new_pid
= xmalloc (sizeof (struct simple_pid_list
));
299 new_pid
->status
= status
;
300 new_pid
->next
= *listp
;
305 in_pid_list_p (struct simple_pid_list
*list
, int pid
)
307 struct simple_pid_list
*p
;
309 for (p
= list
; p
!= NULL
; p
= p
->next
)
316 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
318 struct simple_pid_list
**p
;
320 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
321 if ((*p
)->pid
== pid
)
323 struct simple_pid_list
*next
= (*p
)->next
;
325 *statusp
= (*p
)->status
;
334 /* A helper function for linux_test_for_tracefork, called after fork (). */
337 linux_tracefork_child (void)
339 ptrace (PTRACE_TRACEME
, 0, 0, 0);
340 kill (getpid (), SIGSTOP
);
345 /* Wrapper function for waitpid which handles EINTR. */
348 my_waitpid (int pid
, int *statusp
, int flags
)
354 ret
= waitpid (pid
, statusp
, flags
);
356 while (ret
== -1 && errno
== EINTR
);
361 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events.
363 First, we try to enable fork tracing on ORIGINAL_PID. If this fails,
364 we know that the feature is not available. This may change the tracing
365 options for ORIGINAL_PID, but we'll be setting them shortly anyway.
367 However, if it succeeds, we don't know for sure that the feature is
368 available; old versions of PTRACE_SETOPTIONS ignored unknown options. We
369 create a child process, attach to it, use PTRACE_SETOPTIONS to enable
370 fork tracing, and let it fork. If the process exits, we assume that we
371 can't use TRACEFORK; if we get the fork notification, and we can extract
372 the new child's PID, then we assume that we can. */
375 linux_test_for_tracefork (int original_pid
)
377 int child_pid
, ret
, status
;
381 /* We don't want those ptrace calls to be interrupted. */
382 block_child_signals (&prev_mask
);
384 linux_supports_tracefork_flag
= 0;
385 linux_supports_tracevforkdone_flag
= 0;
387 ret
= ptrace (PTRACE_SETOPTIONS
, original_pid
, 0, PTRACE_O_TRACEFORK
);
390 restore_child_signals_mask (&prev_mask
);
396 perror_with_name (("fork"));
399 linux_tracefork_child ();
401 ret
= my_waitpid (child_pid
, &status
, 0);
403 perror_with_name (("waitpid"));
404 else if (ret
!= child_pid
)
405 error (_("linux_test_for_tracefork: waitpid: unexpected result %d."), ret
);
406 if (! WIFSTOPPED (status
))
407 error (_("linux_test_for_tracefork: waitpid: unexpected status %d."),
410 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0, PTRACE_O_TRACEFORK
);
413 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
416 warning (_("linux_test_for_tracefork: failed to kill child"));
417 restore_child_signals_mask (&prev_mask
);
421 ret
= my_waitpid (child_pid
, &status
, 0);
422 if (ret
!= child_pid
)
423 warning (_("linux_test_for_tracefork: failed "
424 "to wait for killed child"));
425 else if (!WIFSIGNALED (status
))
426 warning (_("linux_test_for_tracefork: unexpected "
427 "wait status 0x%x from killed child"), status
);
429 restore_child_signals_mask (&prev_mask
);
433 /* Check whether PTRACE_O_TRACEVFORKDONE is available. */
434 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
435 PTRACE_O_TRACEFORK
| PTRACE_O_TRACEVFORKDONE
);
436 linux_supports_tracevforkdone_flag
= (ret
== 0);
438 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
440 warning (_("linux_test_for_tracefork: failed to resume child"));
442 ret
= my_waitpid (child_pid
, &status
, 0);
444 if (ret
== child_pid
&& WIFSTOPPED (status
)
445 && status
>> 16 == PTRACE_EVENT_FORK
)
448 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
449 if (ret
== 0 && second_pid
!= 0)
453 linux_supports_tracefork_flag
= 1;
454 my_waitpid (second_pid
, &second_status
, 0);
455 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
457 warning (_("linux_test_for_tracefork: "
458 "failed to kill second child"));
459 my_waitpid (second_pid
, &status
, 0);
463 warning (_("linux_test_for_tracefork: unexpected result from waitpid "
464 "(%d, status 0x%x)"), ret
, status
);
466 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
468 warning (_("linux_test_for_tracefork: failed to kill child"));
469 my_waitpid (child_pid
, &status
, 0);
471 restore_child_signals_mask (&prev_mask
);
474 /* Determine if PTRACE_O_TRACESYSGOOD can be used to follow syscalls.
476 We try to enable syscall tracing on ORIGINAL_PID. If this fails,
477 we know that the feature is not available. This may change the tracing
478 options for ORIGINAL_PID, but we'll be setting them shortly anyway. */
481 linux_test_for_tracesysgood (int original_pid
)
486 /* We don't want those ptrace calls to be interrupted. */
487 block_child_signals (&prev_mask
);
489 linux_supports_tracesysgood_flag
= 0;
491 ret
= ptrace (PTRACE_SETOPTIONS
, original_pid
, 0, PTRACE_O_TRACESYSGOOD
);
495 linux_supports_tracesysgood_flag
= 1;
497 restore_child_signals_mask (&prev_mask
);
500 /* Determine wether we support PTRACE_O_TRACESYSGOOD option available.
501 This function also sets linux_supports_tracesysgood_flag. */
504 linux_supports_tracesysgood (int pid
)
506 if (linux_supports_tracesysgood_flag
== -1)
507 linux_test_for_tracesysgood (pid
);
508 return linux_supports_tracesysgood_flag
;
511 /* Return non-zero iff we have tracefork functionality available.
512 This function also sets linux_supports_tracefork_flag. */
515 linux_supports_tracefork (int pid
)
517 if (linux_supports_tracefork_flag
== -1)
518 linux_test_for_tracefork (pid
);
519 return linux_supports_tracefork_flag
;
523 linux_supports_tracevforkdone (int pid
)
525 if (linux_supports_tracefork_flag
== -1)
526 linux_test_for_tracefork (pid
);
527 return linux_supports_tracevforkdone_flag
;
531 linux_enable_tracesysgood (ptid_t ptid
)
533 int pid
= ptid_get_lwp (ptid
);
536 pid
= ptid_get_pid (ptid
);
538 if (linux_supports_tracesysgood (pid
) == 0)
541 current_ptrace_options
|= PTRACE_O_TRACESYSGOOD
;
543 ptrace (PTRACE_SETOPTIONS
, pid
, 0, current_ptrace_options
);
548 linux_enable_event_reporting (ptid_t ptid
)
550 int pid
= ptid_get_lwp (ptid
);
553 pid
= ptid_get_pid (ptid
);
555 if (! linux_supports_tracefork (pid
))
558 current_ptrace_options
|= PTRACE_O_TRACEFORK
| PTRACE_O_TRACEVFORK
559 | PTRACE_O_TRACEEXEC
| PTRACE_O_TRACECLONE
;
561 if (linux_supports_tracevforkdone (pid
))
562 current_ptrace_options
|= PTRACE_O_TRACEVFORKDONE
;
564 /* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to support
565 read-only process state. */
567 ptrace (PTRACE_SETOPTIONS
, pid
, 0, current_ptrace_options
);
571 linux_child_post_attach (int pid
)
573 linux_enable_event_reporting (pid_to_ptid (pid
));
574 linux_enable_tracesysgood (pid_to_ptid (pid
));
578 linux_child_post_startup_inferior (ptid_t ptid
)
580 linux_enable_event_reporting (ptid
);
581 linux_enable_tracesysgood (ptid
);
585 linux_child_follow_fork (struct target_ops
*ops
, int follow_child
)
589 int parent_pid
, child_pid
;
591 block_child_signals (&prev_mask
);
593 has_vforked
= (inferior_thread ()->pending_follow
.kind
594 == TARGET_WAITKIND_VFORKED
);
595 parent_pid
= ptid_get_lwp (inferior_ptid
);
597 parent_pid
= ptid_get_pid (inferior_ptid
);
598 child_pid
= PIDGET (inferior_thread ()->pending_follow
.value
.related_pid
);
601 linux_enable_event_reporting (pid_to_ptid (child_pid
));
604 && !non_stop
/* Non-stop always resumes both branches. */
605 && (!target_is_async_p () || sync_execution
)
606 && !(follow_child
|| detach_fork
|| sched_multi
))
608 /* The parent stays blocked inside the vfork syscall until the
609 child execs or exits. If we don't let the child run, then
610 the parent stays blocked. If we're telling the parent to run
611 in the foreground, the user will not be able to ctrl-c to get
612 back the terminal, effectively hanging the debug session. */
613 fprintf_filtered (gdb_stderr
, _("\
614 Can not resume the parent process over vfork in the foreground while\n\
615 holding the child stopped. Try \"set detach-on-fork\" or \
616 \"set schedule-multiple\".\n"));
617 /* FIXME output string > 80 columns. */
623 struct lwp_info
*child_lp
= NULL
;
625 /* We're already attached to the parent, by default. */
627 /* Detach new forked process? */
630 /* Before detaching from the child, remove all breakpoints
631 from it. If we forked, then this has already been taken
632 care of by infrun.c. If we vforked however, any
633 breakpoint inserted in the parent is visible in the
634 child, even those added while stopped in a vfork
635 catchpoint. This will remove the breakpoints from the
636 parent also, but they'll be reinserted below. */
639 /* keep breakpoints list in sync. */
640 remove_breakpoints_pid (GET_PID (inferior_ptid
));
643 if (info_verbose
|| debug_linux_nat
)
645 target_terminal_ours ();
646 fprintf_filtered (gdb_stdlog
,
647 "Detaching after fork from "
648 "child process %d.\n",
652 ptrace (PTRACE_DETACH
, child_pid
, 0, 0);
656 struct inferior
*parent_inf
, *child_inf
;
657 struct cleanup
*old_chain
;
659 /* Add process to GDB's tables. */
660 child_inf
= add_inferior (child_pid
);
662 parent_inf
= current_inferior ();
663 child_inf
->attach_flag
= parent_inf
->attach_flag
;
664 copy_terminal_info (child_inf
, parent_inf
);
666 old_chain
= save_inferior_ptid ();
667 save_current_program_space ();
669 inferior_ptid
= ptid_build (child_pid
, child_pid
, 0);
670 add_thread (inferior_ptid
);
671 child_lp
= add_lwp (inferior_ptid
);
672 child_lp
->stopped
= 1;
673 child_lp
->last_resume_kind
= resume_stop
;
675 /* If this is a vfork child, then the address-space is
676 shared with the parent. */
679 child_inf
->pspace
= parent_inf
->pspace
;
680 child_inf
->aspace
= parent_inf
->aspace
;
682 /* The parent will be frozen until the child is done
683 with the shared region. Keep track of the
685 child_inf
->vfork_parent
= parent_inf
;
686 child_inf
->pending_detach
= 0;
687 parent_inf
->vfork_child
= child_inf
;
688 parent_inf
->pending_detach
= 0;
692 child_inf
->aspace
= new_address_space ();
693 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
694 child_inf
->removable
= 1;
695 set_current_program_space (child_inf
->pspace
);
696 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
698 /* Let the shared library layer (solib-svr4) learn about
699 this new process, relocate the cloned exec, pull in
700 shared libraries, and install the solib event
701 breakpoint. If a "cloned-VM" event was propagated
702 better throughout the core, this wouldn't be
704 solib_create_inferior_hook (0);
707 /* Let the thread_db layer learn about this new process. */
708 check_for_thread_db ();
710 do_cleanups (old_chain
);
715 struct lwp_info
*parent_lp
;
716 struct inferior
*parent_inf
;
718 parent_inf
= current_inferior ();
720 /* If we detached from the child, then we have to be careful
721 to not insert breakpoints in the parent until the child
722 is done with the shared memory region. However, if we're
723 staying attached to the child, then we can and should
724 insert breakpoints, so that we can debug it. A
725 subsequent child exec or exit is enough to know when does
726 the child stops using the parent's address space. */
727 parent_inf
->waiting_for_vfork_done
= detach_fork
;
728 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
730 parent_lp
= find_lwp_pid (pid_to_ptid (parent_pid
));
731 gdb_assert (linux_supports_tracefork_flag
>= 0);
733 if (linux_supports_tracevforkdone (0))
736 fprintf_unfiltered (gdb_stdlog
,
737 "LCFF: waiting for VFORK_DONE on %d\n",
739 parent_lp
->stopped
= 1;
741 /* We'll handle the VFORK_DONE event like any other
742 event, in target_wait. */
746 /* We can't insert breakpoints until the child has
747 finished with the shared memory region. We need to
748 wait until that happens. Ideal would be to just
750 - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0);
751 - waitpid (parent_pid, &status, __WALL);
752 However, most architectures can't handle a syscall
753 being traced on the way out if it wasn't traced on
756 We might also think to loop, continuing the child
757 until it exits or gets a SIGTRAP. One problem is
758 that the child might call ptrace with PTRACE_TRACEME.
760 There's no simple and reliable way to figure out when
761 the vforked child will be done with its copy of the
762 shared memory. We could step it out of the syscall,
763 two instructions, let it go, and then single-step the
764 parent once. When we have hardware single-step, this
765 would work; with software single-step it could still
766 be made to work but we'd have to be able to insert
767 single-step breakpoints in the child, and we'd have
768 to insert -just- the single-step breakpoint in the
769 parent. Very awkward.
771 In the end, the best we can do is to make sure it
772 runs for a little while. Hopefully it will be out of
773 range of any breakpoints we reinsert. Usually this
774 is only the single-step breakpoint at vfork's return
778 fprintf_unfiltered (gdb_stdlog
,
779 "LCFF: no VFORK_DONE "
780 "support, sleeping a bit\n");
784 /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event,
785 and leave it pending. The next linux_nat_resume call
786 will notice a pending event, and bypasses actually
787 resuming the inferior. */
788 parent_lp
->status
= 0;
789 parent_lp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
790 parent_lp
->stopped
= 1;
792 /* If we're in async mode, need to tell the event loop
793 there's something here to process. */
794 if (target_can_async_p ())
801 struct inferior
*parent_inf
, *child_inf
;
802 struct lwp_info
*child_lp
;
803 struct program_space
*parent_pspace
;
805 if (info_verbose
|| debug_linux_nat
)
807 target_terminal_ours ();
809 fprintf_filtered (gdb_stdlog
,
810 _("Attaching after process %d "
811 "vfork to child process %d.\n"),
812 parent_pid
, child_pid
);
814 fprintf_filtered (gdb_stdlog
,
815 _("Attaching after process %d "
816 "fork to child process %d.\n"),
817 parent_pid
, child_pid
);
820 /* Add the new inferior first, so that the target_detach below
821 doesn't unpush the target. */
823 child_inf
= add_inferior (child_pid
);
825 parent_inf
= current_inferior ();
826 child_inf
->attach_flag
= parent_inf
->attach_flag
;
827 copy_terminal_info (child_inf
, parent_inf
);
829 parent_pspace
= parent_inf
->pspace
;
831 /* If we're vforking, we want to hold on to the parent until the
832 child exits or execs. At child exec or exit time we can
833 remove the old breakpoints from the parent and detach or
834 resume debugging it. Otherwise, detach the parent now; we'll
835 want to reuse it's program/address spaces, but we can't set
836 them to the child before removing breakpoints from the
837 parent, otherwise, the breakpoints module could decide to
838 remove breakpoints from the wrong process (since they'd be
839 assigned to the same address space). */
843 gdb_assert (child_inf
->vfork_parent
== NULL
);
844 gdb_assert (parent_inf
->vfork_child
== NULL
);
845 child_inf
->vfork_parent
= parent_inf
;
846 child_inf
->pending_detach
= 0;
847 parent_inf
->vfork_child
= child_inf
;
848 parent_inf
->pending_detach
= detach_fork
;
849 parent_inf
->waiting_for_vfork_done
= 0;
851 else if (detach_fork
)
852 target_detach (NULL
, 0);
854 /* Note that the detach above makes PARENT_INF dangling. */
856 /* Add the child thread to the appropriate lists, and switch to
857 this new thread, before cloning the program space, and
858 informing the solib layer about this new process. */
860 inferior_ptid
= ptid_build (child_pid
, child_pid
, 0);
861 add_thread (inferior_ptid
);
862 child_lp
= add_lwp (inferior_ptid
);
863 child_lp
->stopped
= 1;
864 child_lp
->last_resume_kind
= resume_stop
;
866 /* If this is a vfork child, then the address-space is shared
867 with the parent. If we detached from the parent, then we can
868 reuse the parent's program/address spaces. */
869 if (has_vforked
|| detach_fork
)
871 child_inf
->pspace
= parent_pspace
;
872 child_inf
->aspace
= child_inf
->pspace
->aspace
;
876 child_inf
->aspace
= new_address_space ();
877 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
878 child_inf
->removable
= 1;
879 set_current_program_space (child_inf
->pspace
);
880 clone_program_space (child_inf
->pspace
, parent_pspace
);
882 /* Let the shared library layer (solib-svr4) learn about
883 this new process, relocate the cloned exec, pull in
884 shared libraries, and install the solib event breakpoint.
885 If a "cloned-VM" event was propagated better throughout
886 the core, this wouldn't be required. */
887 solib_create_inferior_hook (0);
890 /* Let the thread_db layer learn about this new process. */
891 check_for_thread_db ();
894 restore_child_signals_mask (&prev_mask
);
900 linux_child_insert_fork_catchpoint (int pid
)
902 return !linux_supports_tracefork (pid
);
906 linux_child_remove_fork_catchpoint (int pid
)
912 linux_child_insert_vfork_catchpoint (int pid
)
914 return !linux_supports_tracefork (pid
);
918 linux_child_remove_vfork_catchpoint (int pid
)
924 linux_child_insert_exec_catchpoint (int pid
)
926 return !linux_supports_tracefork (pid
);
930 linux_child_remove_exec_catchpoint (int pid
)
936 linux_child_set_syscall_catchpoint (int pid
, int needed
, int any_count
,
937 int table_size
, int *table
)
939 if (!linux_supports_tracesysgood (pid
))
942 /* On GNU/Linux, we ignore the arguments. It means that we only
943 enable the syscall catchpoints, but do not disable them.
945 Also, we do not use the `table' information because we do not
946 filter system calls here. We let GDB do the logic for us. */
950 /* On GNU/Linux there are no real LWP's. The closest thing to LWP's
951 are processes sharing the same VM space. A multi-threaded process
952 is basically a group of such processes. However, such a grouping
953 is almost entirely a user-space issue; the kernel doesn't enforce
954 such a grouping at all (this might change in the future). In
955 general, we'll rely on the threads library (i.e. the GNU/Linux
956 Threads library) to provide such a grouping.
958 It is perfectly well possible to write a multi-threaded application
959 without the assistance of a threads library, by using the clone
960 system call directly. This module should be able to give some
961 rudimentary support for debugging such applications if developers
962 specify the CLONE_PTRACE flag in the clone system call, and are
963 using the Linux kernel 2.4 or above.
965 Note that there are some peculiarities in GNU/Linux that affect
968 - In general one should specify the __WCLONE flag to waitpid in
969 order to make it report events for any of the cloned processes
970 (and leave it out for the initial process). However, if a cloned
971 process has exited the exit status is only reported if the
972 __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but
973 we cannot use it since GDB must work on older systems too.
975 - When a traced, cloned process exits and is waited for by the
976 debugger, the kernel reassigns it to the original parent and
977 keeps it around as a "zombie". Somehow, the GNU/Linux Threads
978 library doesn't notice this, which leads to the "zombie problem":
979 When debugged a multi-threaded process that spawns a lot of
980 threads will run out of processes, even if the threads exit,
981 because the "zombies" stay around. */
983 /* List of known LWPs. */
984 struct lwp_info
*lwp_list
;
987 /* Original signal mask. */
988 static sigset_t normal_mask
;
990 /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in
991 _initialize_linux_nat. */
992 static sigset_t suspend_mask
;
994 /* Signals to block to make that sigsuspend work. */
995 static sigset_t blocked_mask
;
997 /* SIGCHLD action. */
998 struct sigaction sigchld_action
;
1000 /* Block child signals (SIGCHLD and linux threads signals), and store
1001 the previous mask in PREV_MASK. */
1004 block_child_signals (sigset_t
*prev_mask
)
1006 /* Make sure SIGCHLD is blocked. */
1007 if (!sigismember (&blocked_mask
, SIGCHLD
))
1008 sigaddset (&blocked_mask
, SIGCHLD
);
1010 sigprocmask (SIG_BLOCK
, &blocked_mask
, prev_mask
);
1013 /* Restore child signals mask, previously returned by
1014 block_child_signals. */
1017 restore_child_signals_mask (sigset_t
*prev_mask
)
1019 sigprocmask (SIG_SETMASK
, prev_mask
, NULL
);
1022 /* Mask of signals to pass directly to the inferior. */
1023 static sigset_t pass_mask
;
1025 /* Update signals to pass to the inferior. */
1027 linux_nat_pass_signals (int numsigs
, unsigned char *pass_signals
)
1031 sigemptyset (&pass_mask
);
1033 for (signo
= 1; signo
< NSIG
; signo
++)
1035 int target_signo
= target_signal_from_host (signo
);
1036 if (target_signo
< numsigs
&& pass_signals
[target_signo
])
1037 sigaddset (&pass_mask
, signo
);
1043 /* Prototypes for local functions. */
1044 static int stop_wait_callback (struct lwp_info
*lp
, void *data
);
1045 static int linux_thread_alive (ptid_t ptid
);
1046 static char *linux_child_pid_to_exec_file (int pid
);
1049 /* Convert wait status STATUS to a string. Used for printing debug
1053 status_to_str (int status
)
1055 static char buf
[64];
1057 if (WIFSTOPPED (status
))
1059 if (WSTOPSIG (status
) == SYSCALL_SIGTRAP
)
1060 snprintf (buf
, sizeof (buf
), "%s (stopped at syscall)",
1061 strsignal (SIGTRAP
));
1063 snprintf (buf
, sizeof (buf
), "%s (stopped)",
1064 strsignal (WSTOPSIG (status
)));
1066 else if (WIFSIGNALED (status
))
1067 snprintf (buf
, sizeof (buf
), "%s (terminated)",
1068 strsignal (WTERMSIG (status
)));
1070 snprintf (buf
, sizeof (buf
), "%d (exited)", WEXITSTATUS (status
));
1075 /* Remove all LWPs belong to PID from the lwp list. */
1078 purge_lwp_list (int pid
)
1080 struct lwp_info
*lp
, *lpprev
, *lpnext
;
1084 for (lp
= lwp_list
; lp
; lp
= lpnext
)
1088 if (ptid_get_pid (lp
->ptid
) == pid
)
1091 lwp_list
= lp
->next
;
1093 lpprev
->next
= lp
->next
;
1102 /* Return the number of known LWPs in the tgid given by PID. */
1108 struct lwp_info
*lp
;
1110 for (lp
= lwp_list
; lp
; lp
= lp
->next
)
1111 if (ptid_get_pid (lp
->ptid
) == pid
)
1117 /* Add the LWP specified by PID to the list. Return a pointer to the
1118 structure describing the new LWP. The LWP should already be stopped
1119 (with an exception for the very first LWP). */
1121 static struct lwp_info
*
1122 add_lwp (ptid_t ptid
)
1124 struct lwp_info
*lp
;
1126 gdb_assert (is_lwp (ptid
));
1128 lp
= (struct lwp_info
*) xmalloc (sizeof (struct lwp_info
));
1130 memset (lp
, 0, sizeof (struct lwp_info
));
1132 lp
->last_resume_kind
= resume_continue
;
1133 lp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
1138 lp
->next
= lwp_list
;
1141 if (num_lwps (GET_PID (ptid
)) > 1 && linux_nat_new_thread
!= NULL
)
1142 linux_nat_new_thread (ptid
);
1147 /* Remove the LWP specified by PID from the list. */
1150 delete_lwp (ptid_t ptid
)
1152 struct lwp_info
*lp
, *lpprev
;
1156 for (lp
= lwp_list
; lp
; lpprev
= lp
, lp
= lp
->next
)
1157 if (ptid_equal (lp
->ptid
, ptid
))
1164 lpprev
->next
= lp
->next
;
1166 lwp_list
= lp
->next
;
1171 /* Return a pointer to the structure describing the LWP corresponding
1172 to PID. If no corresponding LWP could be found, return NULL. */
1174 static struct lwp_info
*
1175 find_lwp_pid (ptid_t ptid
)
1177 struct lwp_info
*lp
;
1181 lwp
= GET_LWP (ptid
);
1183 lwp
= GET_PID (ptid
);
1185 for (lp
= lwp_list
; lp
; lp
= lp
->next
)
1186 if (lwp
== GET_LWP (lp
->ptid
))
1192 /* Call CALLBACK with its second argument set to DATA for every LWP in
1193 the list. If CALLBACK returns 1 for a particular LWP, return a
1194 pointer to the structure describing that LWP immediately.
1195 Otherwise return NULL. */
1198 iterate_over_lwps (ptid_t filter
,
1199 int (*callback
) (struct lwp_info
*, void *),
1202 struct lwp_info
*lp
, *lpnext
;
1204 for (lp
= lwp_list
; lp
; lp
= lpnext
)
1208 if (ptid_match (lp
->ptid
, filter
))
1210 if ((*callback
) (lp
, data
))
1218 /* Update our internal state when changing from one checkpoint to
1219 another indicated by NEW_PTID. We can only switch single-threaded
1220 applications, so we only create one new LWP, and the previous list
1224 linux_nat_switch_fork (ptid_t new_ptid
)
1226 struct lwp_info
*lp
;
1228 purge_lwp_list (GET_PID (inferior_ptid
));
1230 lp
= add_lwp (new_ptid
);
1233 /* This changes the thread's ptid while preserving the gdb thread
1234 num. Also changes the inferior pid, while preserving the
1236 thread_change_ptid (inferior_ptid
, new_ptid
);
1238 /* We've just told GDB core that the thread changed target id, but,
1239 in fact, it really is a different thread, with different register
1241 registers_changed ();
1244 /* Handle the exit of a single thread LP. */
1247 exit_lwp (struct lwp_info
*lp
)
1249 struct thread_info
*th
= find_thread_ptid (lp
->ptid
);
1253 if (print_thread_events
)
1254 printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp
->ptid
));
1256 delete_thread (lp
->ptid
);
1259 delete_lwp (lp
->ptid
);
1262 /* Detect `T (stopped)' in `/proc/PID/status'.
1263 Other states including `T (tracing stop)' are reported as false. */
1266 pid_is_stopped (pid_t pid
)
1272 snprintf (buf
, sizeof (buf
), "/proc/%d/status", (int) pid
);
1273 status_file
= fopen (buf
, "r");
1274 if (status_file
!= NULL
)
1278 while (fgets (buf
, sizeof (buf
), status_file
))
1280 if (strncmp (buf
, "State:", 6) == 0)
1286 if (have_state
&& strstr (buf
, "T (stopped)") != NULL
)
1288 fclose (status_file
);
1293 /* Wait for the LWP specified by LP, which we have just attached to.
1294 Returns a wait status for that LWP, to cache. */
1297 linux_nat_post_attach_wait (ptid_t ptid
, int first
, int *cloned
,
1300 pid_t new_pid
, pid
= GET_LWP (ptid
);
1303 if (pid_is_stopped (pid
))
1305 if (debug_linux_nat
)
1306 fprintf_unfiltered (gdb_stdlog
,
1307 "LNPAW: Attaching to a stopped process\n");
1309 /* The process is definitely stopped. It is in a job control
1310 stop, unless the kernel predates the TASK_STOPPED /
1311 TASK_TRACED distinction, in which case it might be in a
1312 ptrace stop. Make sure it is in a ptrace stop; from there we
1313 can kill it, signal it, et cetera.
1315 First make sure there is a pending SIGSTOP. Since we are
1316 already attached, the process can not transition from stopped
1317 to running without a PTRACE_CONT; so we know this signal will
1318 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1319 probably already in the queue (unless this kernel is old
1320 enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP
1321 is not an RT signal, it can only be queued once. */
1322 kill_lwp (pid
, SIGSTOP
);
1324 /* Finally, resume the stopped process. This will deliver the SIGSTOP
1325 (or a higher priority signal, just like normal PTRACE_ATTACH). */
1326 ptrace (PTRACE_CONT
, pid
, 0, 0);
1329 /* Make sure the initial process is stopped. The user-level threads
1330 layer might want to poke around in the inferior, and that won't
1331 work if things haven't stabilized yet. */
1332 new_pid
= my_waitpid (pid
, &status
, 0);
1333 if (new_pid
== -1 && errno
== ECHILD
)
1336 warning (_("%s is a cloned process"), target_pid_to_str (ptid
));
1338 /* Try again with __WCLONE to check cloned processes. */
1339 new_pid
= my_waitpid (pid
, &status
, __WCLONE
);
1343 gdb_assert (pid
== new_pid
);
1345 if (!WIFSTOPPED (status
))
1347 /* The pid we tried to attach has apparently just exited. */
1348 if (debug_linux_nat
)
1349 fprintf_unfiltered (gdb_stdlog
, "LNPAW: Failed to stop %d: %s",
1350 pid
, status_to_str (status
));
1354 if (WSTOPSIG (status
) != SIGSTOP
)
1357 if (debug_linux_nat
)
1358 fprintf_unfiltered (gdb_stdlog
,
1359 "LNPAW: Received %s after attaching\n",
1360 status_to_str (status
));
1366 /* Attach to the LWP specified by PID. Return 0 if successful, -1 if
1367 the new LWP could not be attached, or 1 if we're already auto
1368 attached to this thread, but haven't processed the
1369 PTRACE_EVENT_CLONE event of its parent thread, so we just ignore
1370 its existance, without considering it an error. */
1373 lin_lwp_attach_lwp (ptid_t ptid
)
1375 struct lwp_info
*lp
;
1379 gdb_assert (is_lwp (ptid
));
1381 block_child_signals (&prev_mask
);
1383 lp
= find_lwp_pid (ptid
);
1384 lwpid
= GET_LWP (ptid
);
1386 /* We assume that we're already attached to any LWP that has an id
1387 equal to the overall process id, and to any LWP that is already
1388 in our list of LWPs. If we're not seeing exit events from threads
1389 and we've had PID wraparound since we last tried to stop all threads,
1390 this assumption might be wrong; fortunately, this is very unlikely
1392 if (lwpid
!= GET_PID (ptid
) && lp
== NULL
)
1394 int status
, cloned
= 0, signalled
= 0;
1396 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) < 0)
1398 if (linux_supports_tracefork_flag
)
1400 /* If we haven't stopped all threads when we get here,
1401 we may have seen a thread listed in thread_db's list,
1402 but not processed the PTRACE_EVENT_CLONE yet. If
1403 that's the case, ignore this new thread, and let
1404 normal event handling discover it later. */
1405 if (in_pid_list_p (stopped_pids
, lwpid
))
1407 /* We've already seen this thread stop, but we
1408 haven't seen the PTRACE_EVENT_CLONE extended
1410 restore_child_signals_mask (&prev_mask
);
1418 /* See if we've got a stop for this new child
1419 pending. If so, we're already attached. */
1420 new_pid
= my_waitpid (lwpid
, &status
, WNOHANG
);
1421 if (new_pid
== -1 && errno
== ECHILD
)
1422 new_pid
= my_waitpid (lwpid
, &status
, __WCLONE
| WNOHANG
);
1425 if (WIFSTOPPED (status
))
1426 add_to_pid_list (&stopped_pids
, lwpid
, status
);
1428 restore_child_signals_mask (&prev_mask
);
1434 /* If we fail to attach to the thread, issue a warning,
1435 but continue. One way this can happen is if thread
1436 creation is interrupted; as of Linux kernel 2.6.19, a
1437 bug may place threads in the thread list and then fail
1439 warning (_("Can't attach %s: %s"), target_pid_to_str (ptid
),
1440 safe_strerror (errno
));
1441 restore_child_signals_mask (&prev_mask
);
1445 if (debug_linux_nat
)
1446 fprintf_unfiltered (gdb_stdlog
,
1447 "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n",
1448 target_pid_to_str (ptid
));
1450 status
= linux_nat_post_attach_wait (ptid
, 0, &cloned
, &signalled
);
1451 if (!WIFSTOPPED (status
))
1453 restore_child_signals_mask (&prev_mask
);
1457 lp
= add_lwp (ptid
);
1459 lp
->cloned
= cloned
;
1460 lp
->signalled
= signalled
;
1461 if (WSTOPSIG (status
) != SIGSTOP
)
1464 lp
->status
= status
;
1467 target_post_attach (GET_LWP (lp
->ptid
));
1469 if (debug_linux_nat
)
1471 fprintf_unfiltered (gdb_stdlog
,
1472 "LLAL: waitpid %s received %s\n",
1473 target_pid_to_str (ptid
),
1474 status_to_str (status
));
1479 /* We assume that the LWP representing the original process is
1480 already stopped. Mark it as stopped in the data structure
1481 that the GNU/linux ptrace layer uses to keep track of
1482 threads. Note that this won't have already been done since
1483 the main thread will have, we assume, been stopped by an
1484 attach from a different layer. */
1486 lp
= add_lwp (ptid
);
1490 lp
->last_resume_kind
= resume_stop
;
1491 restore_child_signals_mask (&prev_mask
);
1496 linux_nat_create_inferior (struct target_ops
*ops
,
1497 char *exec_file
, char *allargs
, char **env
,
1500 #ifdef HAVE_PERSONALITY
1501 int personality_orig
= 0, personality_set
= 0;
1502 #endif /* HAVE_PERSONALITY */
1504 /* The fork_child mechanism is synchronous and calls target_wait, so
1505 we have to mask the async mode. */
1507 #ifdef HAVE_PERSONALITY
1508 if (disable_randomization
)
1511 personality_orig
= personality (0xffffffff);
1512 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
1514 personality_set
= 1;
1515 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
1517 if (errno
!= 0 || (personality_set
1518 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
1519 warning (_("Error disabling address space randomization: %s"),
1520 safe_strerror (errno
));
1522 #endif /* HAVE_PERSONALITY */
1524 /* Make sure we report all signals during startup. */
1525 linux_nat_pass_signals (0, NULL
);
1527 linux_ops
->to_create_inferior (ops
, exec_file
, allargs
, env
, from_tty
);
1529 #ifdef HAVE_PERSONALITY
1530 if (personality_set
)
1533 personality (personality_orig
);
1535 warning (_("Error restoring address space randomization: %s"),
1536 safe_strerror (errno
));
1538 #endif /* HAVE_PERSONALITY */
1542 linux_nat_attach (struct target_ops
*ops
, char *args
, int from_tty
)
1544 struct lwp_info
*lp
;
1548 /* Make sure we report all signals during attach. */
1549 linux_nat_pass_signals (0, NULL
);
1551 linux_ops
->to_attach (ops
, args
, from_tty
);
1553 /* The ptrace base target adds the main thread with (pid,0,0)
1554 format. Decorate it with lwp info. */
1555 ptid
= BUILD_LWP (GET_PID (inferior_ptid
), GET_PID (inferior_ptid
));
1556 thread_change_ptid (inferior_ptid
, ptid
);
1558 /* Add the initial process as the first LWP to the list. */
1559 lp
= add_lwp (ptid
);
1561 status
= linux_nat_post_attach_wait (lp
->ptid
, 1, &lp
->cloned
,
1563 if (!WIFSTOPPED (status
))
1565 if (WIFEXITED (status
))
1567 int exit_code
= WEXITSTATUS (status
);
1569 target_terminal_ours ();
1570 target_mourn_inferior ();
1572 error (_("Unable to attach: program exited normally."));
1574 error (_("Unable to attach: program exited with code %d."),
1577 else if (WIFSIGNALED (status
))
1579 enum target_signal signo
;
1581 target_terminal_ours ();
1582 target_mourn_inferior ();
1584 signo
= target_signal_from_host (WTERMSIG (status
));
1585 error (_("Unable to attach: program terminated with signal "
1587 target_signal_to_name (signo
),
1588 target_signal_to_string (signo
));
1591 internal_error (__FILE__
, __LINE__
,
1592 _("unexpected status %d for PID %ld"),
1593 status
, (long) GET_LWP (ptid
));
1598 /* Save the wait status to report later. */
1600 if (debug_linux_nat
)
1601 fprintf_unfiltered (gdb_stdlog
,
1602 "LNA: waitpid %ld, saving status %s\n",
1603 (long) GET_PID (lp
->ptid
), status_to_str (status
));
1605 lp
->status
= status
;
1607 if (target_can_async_p ())
1608 target_async (inferior_event_handler
, 0);
1611 /* Get pending status of LP. */
1613 get_pending_status (struct lwp_info
*lp
, int *status
)
1615 enum target_signal signo
= TARGET_SIGNAL_0
;
1617 /* If we paused threads momentarily, we may have stored pending
1618 events in lp->status or lp->waitstatus (see stop_wait_callback),
1619 and GDB core hasn't seen any signal for those threads.
1620 Otherwise, the last signal reported to the core is found in the
1621 thread object's stop_signal.
1623 There's a corner case that isn't handled here at present. Only
1624 if the thread stopped with a TARGET_WAITKIND_STOPPED does
1625 stop_signal make sense as a real signal to pass to the inferior.
1626 Some catchpoint related events, like
1627 TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set
1628 to TARGET_SIGNAL_SIGTRAP when the catchpoint triggers. But,
1629 those traps are debug API (ptrace in our case) related and
1630 induced; the inferior wouldn't see them if it wasn't being
1631 traced. Hence, we should never pass them to the inferior, even
1632 when set to pass state. Since this corner case isn't handled by
1633 infrun.c when proceeding with a signal, for consistency, neither
1634 do we handle it here (or elsewhere in the file we check for
1635 signal pass state). Normally SIGTRAP isn't set to pass state, so
1636 this is really a corner case. */
1638 if (lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
1639 signo
= TARGET_SIGNAL_0
; /* a pending ptrace event, not a real signal. */
1640 else if (lp
->status
)
1641 signo
= target_signal_from_host (WSTOPSIG (lp
->status
));
1642 else if (non_stop
&& !is_executing (lp
->ptid
))
1644 struct thread_info
*tp
= find_thread_ptid (lp
->ptid
);
1646 signo
= tp
->suspend
.stop_signal
;
1650 struct target_waitstatus last
;
1653 get_last_target_status (&last_ptid
, &last
);
1655 if (GET_LWP (lp
->ptid
) == GET_LWP (last_ptid
))
1657 struct thread_info
*tp
= find_thread_ptid (lp
->ptid
);
1659 signo
= tp
->suspend
.stop_signal
;
1665 if (signo
== TARGET_SIGNAL_0
)
1667 if (debug_linux_nat
)
1668 fprintf_unfiltered (gdb_stdlog
,
1669 "GPT: lwp %s has no pending signal\n",
1670 target_pid_to_str (lp
->ptid
));
1672 else if (!signal_pass_state (signo
))
1674 if (debug_linux_nat
)
1675 fprintf_unfiltered (gdb_stdlog
,
1676 "GPT: lwp %s had signal %s, "
1677 "but it is in no pass state\n",
1678 target_pid_to_str (lp
->ptid
),
1679 target_signal_to_string (signo
));
1683 *status
= W_STOPCODE (target_signal_to_host (signo
));
1685 if (debug_linux_nat
)
1686 fprintf_unfiltered (gdb_stdlog
,
1687 "GPT: lwp %s has pending signal %s\n",
1688 target_pid_to_str (lp
->ptid
),
1689 target_signal_to_string (signo
));
1696 detach_callback (struct lwp_info
*lp
, void *data
)
1698 gdb_assert (lp
->status
== 0 || WIFSTOPPED (lp
->status
));
1700 if (debug_linux_nat
&& lp
->status
)
1701 fprintf_unfiltered (gdb_stdlog
, "DC: Pending %s for %s on detach.\n",
1702 strsignal (WSTOPSIG (lp
->status
)),
1703 target_pid_to_str (lp
->ptid
));
1705 /* If there is a pending SIGSTOP, get rid of it. */
1708 if (debug_linux_nat
)
1709 fprintf_unfiltered (gdb_stdlog
,
1710 "DC: Sending SIGCONT to %s\n",
1711 target_pid_to_str (lp
->ptid
));
1713 kill_lwp (GET_LWP (lp
->ptid
), SIGCONT
);
1717 /* We don't actually detach from the LWP that has an id equal to the
1718 overall process id just yet. */
1719 if (GET_LWP (lp
->ptid
) != GET_PID (lp
->ptid
))
1723 /* Pass on any pending signal for this LWP. */
1724 get_pending_status (lp
, &status
);
1727 if (ptrace (PTRACE_DETACH
, GET_LWP (lp
->ptid
), 0,
1728 WSTOPSIG (status
)) < 0)
1729 error (_("Can't detach %s: %s"), target_pid_to_str (lp
->ptid
),
1730 safe_strerror (errno
));
1732 if (debug_linux_nat
)
1733 fprintf_unfiltered (gdb_stdlog
,
1734 "PTRACE_DETACH (%s, %s, 0) (OK)\n",
1735 target_pid_to_str (lp
->ptid
),
1736 strsignal (WSTOPSIG (status
)));
1738 delete_lwp (lp
->ptid
);
1745 linux_nat_detach (struct target_ops
*ops
, char *args
, int from_tty
)
1749 struct lwp_info
*main_lwp
;
1751 pid
= GET_PID (inferior_ptid
);
1753 if (target_can_async_p ())
1754 linux_nat_async (NULL
, 0);
1756 /* Stop all threads before detaching. ptrace requires that the
1757 thread is stopped to sucessfully detach. */
1758 iterate_over_lwps (pid_to_ptid (pid
), stop_callback
, NULL
);
1759 /* ... and wait until all of them have reported back that
1760 they're no longer running. */
1761 iterate_over_lwps (pid_to_ptid (pid
), stop_wait_callback
, NULL
);
1763 iterate_over_lwps (pid_to_ptid (pid
), detach_callback
, NULL
);
1765 /* Only the initial process should be left right now. */
1766 gdb_assert (num_lwps (GET_PID (inferior_ptid
)) == 1);
1768 main_lwp
= find_lwp_pid (pid_to_ptid (pid
));
1770 /* Pass on any pending signal for the last LWP. */
1771 if ((args
== NULL
|| *args
== '\0')
1772 && get_pending_status (main_lwp
, &status
) != -1
1773 && WIFSTOPPED (status
))
1775 /* Put the signal number in ARGS so that inf_ptrace_detach will
1776 pass it along with PTRACE_DETACH. */
1778 sprintf (args
, "%d", (int) WSTOPSIG (status
));
1779 if (debug_linux_nat
)
1780 fprintf_unfiltered (gdb_stdlog
,
1781 "LND: Sending signal %s to %s\n",
1783 target_pid_to_str (main_lwp
->ptid
));
1786 delete_lwp (main_lwp
->ptid
);
1788 if (forks_exist_p ())
1790 /* Multi-fork case. The current inferior_ptid is being detached
1791 from, but there are other viable forks to debug. Detach from
1792 the current fork, and context-switch to the first
1794 linux_fork_detach (args
, from_tty
);
1796 if (non_stop
&& target_can_async_p ())
1797 target_async (inferior_event_handler
, 0);
1800 linux_ops
->to_detach (ops
, args
, from_tty
);
1806 resume_lwp (struct lwp_info
*lp
, int step
)
1810 struct inferior
*inf
= find_inferior_pid (GET_PID (lp
->ptid
));
1812 if (inf
->vfork_child
!= NULL
)
1814 if (debug_linux_nat
)
1815 fprintf_unfiltered (gdb_stdlog
,
1816 "RC: Not resuming %s (vfork parent)\n",
1817 target_pid_to_str (lp
->ptid
));
1819 else if (lp
->status
== 0
1820 && lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
)
1822 if (debug_linux_nat
)
1823 fprintf_unfiltered (gdb_stdlog
,
1824 "RC: PTRACE_CONT %s, 0, 0 (resuming sibling)\n",
1825 target_pid_to_str (lp
->ptid
));
1827 linux_ops
->to_resume (linux_ops
,
1828 pid_to_ptid (GET_LWP (lp
->ptid
)),
1829 step
, TARGET_SIGNAL_0
);
1832 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
1833 lp
->stopped_by_watchpoint
= 0;
1837 if (debug_linux_nat
)
1838 fprintf_unfiltered (gdb_stdlog
,
1839 "RC: Not resuming sibling %s (has pending)\n",
1840 target_pid_to_str (lp
->ptid
));
1845 if (debug_linux_nat
)
1846 fprintf_unfiltered (gdb_stdlog
,
1847 "RC: Not resuming sibling %s (not stopped)\n",
1848 target_pid_to_str (lp
->ptid
));
1853 resume_callback (struct lwp_info
*lp
, void *data
)
1860 resume_clear_callback (struct lwp_info
*lp
, void *data
)
1863 lp
->last_resume_kind
= resume_stop
;
1868 resume_set_callback (struct lwp_info
*lp
, void *data
)
1871 lp
->last_resume_kind
= resume_continue
;
1876 linux_nat_resume (struct target_ops
*ops
,
1877 ptid_t ptid
, int step
, enum target_signal signo
)
1880 struct lwp_info
*lp
;
1883 if (debug_linux_nat
)
1884 fprintf_unfiltered (gdb_stdlog
,
1885 "LLR: Preparing to %s %s, %s, inferior_ptid %s\n",
1886 step
? "step" : "resume",
1887 target_pid_to_str (ptid
),
1888 (signo
!= TARGET_SIGNAL_0
1889 ? strsignal (target_signal_to_host (signo
)) : "0"),
1890 target_pid_to_str (inferior_ptid
));
1892 block_child_signals (&prev_mask
);
1894 /* A specific PTID means `step only this process id'. */
1895 resume_many
= (ptid_equal (minus_one_ptid
, ptid
)
1896 || ptid_is_pid (ptid
));
1898 /* Mark the lwps we're resuming as resumed. */
1899 iterate_over_lwps (ptid
, resume_set_callback
, NULL
);
1901 /* See if it's the current inferior that should be handled
1904 lp
= find_lwp_pid (inferior_ptid
);
1906 lp
= find_lwp_pid (ptid
);
1907 gdb_assert (lp
!= NULL
);
1909 /* Remember if we're stepping. */
1911 lp
->last_resume_kind
= step
? resume_step
: resume_continue
;
1913 /* If we have a pending wait status for this thread, there is no
1914 point in resuming the process. But first make sure that
1915 linux_nat_wait won't preemptively handle the event - we
1916 should never take this short-circuit if we are going to
1917 leave LP running, since we have skipped resuming all the
1918 other threads. This bit of code needs to be synchronized
1919 with linux_nat_wait. */
1921 if (lp
->status
&& WIFSTOPPED (lp
->status
))
1924 && WSTOPSIG (lp
->status
)
1925 && sigismember (&pass_mask
, WSTOPSIG (lp
->status
)))
1927 if (debug_linux_nat
)
1928 fprintf_unfiltered (gdb_stdlog
,
1929 "LLR: Not short circuiting for ignored "
1930 "status 0x%x\n", lp
->status
);
1932 /* FIXME: What should we do if we are supposed to continue
1933 this thread with a signal? */
1934 gdb_assert (signo
== TARGET_SIGNAL_0
);
1935 signo
= target_signal_from_host (WSTOPSIG (lp
->status
));
1940 if (lp
->status
|| lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
1942 /* FIXME: What should we do if we are supposed to continue
1943 this thread with a signal? */
1944 gdb_assert (signo
== TARGET_SIGNAL_0
);
1946 if (debug_linux_nat
)
1947 fprintf_unfiltered (gdb_stdlog
,
1948 "LLR: Short circuiting for status 0x%x\n",
1951 restore_child_signals_mask (&prev_mask
);
1952 if (target_can_async_p ())
1954 target_async (inferior_event_handler
, 0);
1955 /* Tell the event loop we have something to process. */
1961 /* Mark LWP as not stopped to prevent it from being continued by
1966 iterate_over_lwps (ptid
, resume_callback
, NULL
);
1968 /* Convert to something the lower layer understands. */
1969 ptid
= pid_to_ptid (GET_LWP (lp
->ptid
));
1971 linux_ops
->to_resume (linux_ops
, ptid
, step
, signo
);
1972 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
1973 lp
->stopped_by_watchpoint
= 0;
1975 if (debug_linux_nat
)
1976 fprintf_unfiltered (gdb_stdlog
,
1977 "LLR: %s %s, %s (resume event thread)\n",
1978 step
? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
1979 target_pid_to_str (ptid
),
1980 (signo
!= TARGET_SIGNAL_0
1981 ? strsignal (target_signal_to_host (signo
)) : "0"));
1983 restore_child_signals_mask (&prev_mask
);
1984 if (target_can_async_p ())
1985 target_async (inferior_event_handler
, 0);
1988 /* Send a signal to an LWP. */
1991 kill_lwp (int lwpid
, int signo
)
1993 /* Use tkill, if possible, in case we are using nptl threads. If tkill
1994 fails, then we are not using nptl threads and we should be using kill. */
1996 #ifdef HAVE_TKILL_SYSCALL
1998 static int tkill_failed
;
2005 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2006 if (errno
!= ENOSYS
)
2013 return kill (lwpid
, signo
);
2016 /* Handle a GNU/Linux syscall trap wait response. If we see a syscall
2017 event, check if the core is interested in it: if not, ignore the
2018 event, and keep waiting; otherwise, we need to toggle the LWP's
2019 syscall entry/exit status, since the ptrace event itself doesn't
2020 indicate it, and report the trap to higher layers. */
2023 linux_handle_syscall_trap (struct lwp_info
*lp
, int stopping
)
2025 struct target_waitstatus
*ourstatus
= &lp
->waitstatus
;
2026 struct gdbarch
*gdbarch
= target_thread_architecture (lp
->ptid
);
2027 int syscall_number
= (int) gdbarch_get_syscall_number (gdbarch
, lp
->ptid
);
2031 /* If we're stopping threads, there's a SIGSTOP pending, which
2032 makes it so that the LWP reports an immediate syscall return,
2033 followed by the SIGSTOP. Skip seeing that "return" using
2034 PTRACE_CONT directly, and let stop_wait_callback collect the
2035 SIGSTOP. Later when the thread is resumed, a new syscall
2036 entry event. If we didn't do this (and returned 0), we'd
2037 leave a syscall entry pending, and our caller, by using
2038 PTRACE_CONT to collect the SIGSTOP, skips the syscall return
2039 itself. Later, when the user re-resumes this LWP, we'd see
2040 another syscall entry event and we'd mistake it for a return.
2042 If stop_wait_callback didn't force the SIGSTOP out of the LWP
2043 (leaving immediately with LWP->signalled set, without issuing
2044 a PTRACE_CONT), it would still be problematic to leave this
2045 syscall enter pending, as later when the thread is resumed,
2046 it would then see the same syscall exit mentioned above,
2047 followed by the delayed SIGSTOP, while the syscall didn't
2048 actually get to execute. It seems it would be even more
2049 confusing to the user. */
2051 if (debug_linux_nat
)
2052 fprintf_unfiltered (gdb_stdlog
,
2053 "LHST: ignoring syscall %d "
2054 "for LWP %ld (stopping threads), "
2055 "resuming with PTRACE_CONT for SIGSTOP\n",
2057 GET_LWP (lp
->ptid
));
2059 lp
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2060 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2064 if (catch_syscall_enabled ())
2066 /* Always update the entry/return state, even if this particular
2067 syscall isn't interesting to the core now. In async mode,
2068 the user could install a new catchpoint for this syscall
2069 between syscall enter/return, and we'll need to know to
2070 report a syscall return if that happens. */
2071 lp
->syscall_state
= (lp
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2072 ? TARGET_WAITKIND_SYSCALL_RETURN
2073 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2075 if (catching_syscall_number (syscall_number
))
2077 /* Alright, an event to report. */
2078 ourstatus
->kind
= lp
->syscall_state
;
2079 ourstatus
->value
.syscall_number
= syscall_number
;
2081 if (debug_linux_nat
)
2082 fprintf_unfiltered (gdb_stdlog
,
2083 "LHST: stopping for %s of syscall %d"
2086 == TARGET_WAITKIND_SYSCALL_ENTRY
2087 ? "entry" : "return",
2089 GET_LWP (lp
->ptid
));
2093 if (debug_linux_nat
)
2094 fprintf_unfiltered (gdb_stdlog
,
2095 "LHST: ignoring %s of syscall %d "
2097 lp
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2098 ? "entry" : "return",
2100 GET_LWP (lp
->ptid
));
2104 /* If we had been syscall tracing, and hence used PT_SYSCALL
2105 before on this LWP, it could happen that the user removes all
2106 syscall catchpoints before we get to process this event.
2107 There are two noteworthy issues here:
2109 - When stopped at a syscall entry event, resuming with
2110 PT_STEP still resumes executing the syscall and reports a
2113 - Only PT_SYSCALL catches syscall enters. If we last
2114 single-stepped this thread, then this event can't be a
2115 syscall enter. If we last single-stepped this thread, this
2116 has to be a syscall exit.
2118 The points above mean that the next resume, be it PT_STEP or
2119 PT_CONTINUE, can not trigger a syscall trace event. */
2120 if (debug_linux_nat
)
2121 fprintf_unfiltered (gdb_stdlog
,
2122 "LHST: caught syscall event "
2123 "with no syscall catchpoints."
2124 " %d for LWP %ld, ignoring\n",
2126 GET_LWP (lp
->ptid
));
2127 lp
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2130 /* The core isn't interested in this event. For efficiency, avoid
2131 stopping all threads only to have the core resume them all again.
2132 Since we're not stopping threads, if we're still syscall tracing
2133 and not stepping, we can't use PTRACE_CONT here, as we'd miss any
2134 subsequent syscall. Simply resume using the inf-ptrace layer,
2135 which knows when to use PT_SYSCALL or PT_CONTINUE. */
2137 /* Note that gdbarch_get_syscall_number may access registers, hence
2139 registers_changed ();
2140 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
2141 lp
->step
, TARGET_SIGNAL_0
);
2145 /* Handle a GNU/Linux extended wait response. If we see a clone
2146 event, we need to add the new LWP to our list (and not report the
2147 trap to higher layers). This function returns non-zero if the
2148 event should be ignored and we should wait again. If STOPPING is
2149 true, the new LWP remains stopped, otherwise it is continued. */
2152 linux_handle_extended_wait (struct lwp_info
*lp
, int status
,
2155 int pid
= GET_LWP (lp
->ptid
);
2156 struct target_waitstatus
*ourstatus
= &lp
->waitstatus
;
2157 int event
= status
>> 16;
2159 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
2160 || event
== PTRACE_EVENT_CLONE
)
2162 unsigned long new_pid
;
2165 ptrace (PTRACE_GETEVENTMSG
, pid
, 0, &new_pid
);
2167 /* If we haven't already seen the new PID stop, wait for it now. */
2168 if (! pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
2170 /* The new child has a pending SIGSTOP. We can't affect it until it
2171 hits the SIGSTOP, but we're already attached. */
2172 ret
= my_waitpid (new_pid
, &status
,
2173 (event
== PTRACE_EVENT_CLONE
) ? __WCLONE
: 0);
2175 perror_with_name (_("waiting for new child"));
2176 else if (ret
!= new_pid
)
2177 internal_error (__FILE__
, __LINE__
,
2178 _("wait returned unexpected PID %d"), ret
);
2179 else if (!WIFSTOPPED (status
))
2180 internal_error (__FILE__
, __LINE__
,
2181 _("wait returned unexpected status 0x%x"), status
);
2184 ourstatus
->value
.related_pid
= ptid_build (new_pid
, new_pid
, 0);
2186 if (event
== PTRACE_EVENT_FORK
2187 && linux_fork_checkpointing_p (GET_PID (lp
->ptid
)))
2189 /* Handle checkpointing by linux-fork.c here as a special
2190 case. We don't want the follow-fork-mode or 'catch fork'
2191 to interfere with this. */
2193 /* This won't actually modify the breakpoint list, but will
2194 physically remove the breakpoints from the child. */
2195 detach_breakpoints (new_pid
);
2197 /* Retain child fork in ptrace (stopped) state. */
2198 if (!find_fork_pid (new_pid
))
2201 /* Report as spurious, so that infrun doesn't want to follow
2202 this fork. We're actually doing an infcall in
2204 ourstatus
->kind
= TARGET_WAITKIND_SPURIOUS
;
2205 linux_enable_event_reporting (pid_to_ptid (new_pid
));
2207 /* Report the stop to the core. */
2211 if (event
== PTRACE_EVENT_FORK
)
2212 ourstatus
->kind
= TARGET_WAITKIND_FORKED
;
2213 else if (event
== PTRACE_EVENT_VFORK
)
2214 ourstatus
->kind
= TARGET_WAITKIND_VFORKED
;
2217 struct lwp_info
*new_lp
;
2219 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2221 if (debug_linux_nat
)
2222 fprintf_unfiltered (gdb_stdlog
,
2223 "LHEW: Got clone event "
2224 "from LWP %d, new child is LWP %ld\n",
2227 new_lp
= add_lwp (BUILD_LWP (new_pid
, GET_PID (lp
->ptid
)));
2229 new_lp
->stopped
= 1;
2231 if (WSTOPSIG (status
) != SIGSTOP
)
2233 /* This can happen if someone starts sending signals to
2234 the new thread before it gets a chance to run, which
2235 have a lower number than SIGSTOP (e.g. SIGUSR1).
2236 This is an unlikely case, and harder to handle for
2237 fork / vfork than for clone, so we do not try - but
2238 we handle it for clone events here. We'll send
2239 the other signal on to the thread below. */
2241 new_lp
->signalled
= 1;
2245 struct thread_info
*tp
;
2247 /* When we stop for an event in some other thread, and
2248 pull the thread list just as this thread has cloned,
2249 we'll have seen the new thread in the thread_db list
2250 before handling the CLONE event (glibc's
2251 pthread_create adds the new thread to the thread list
2252 before clone'ing, and has the kernel fill in the
2253 thread's tid on the clone call with
2254 CLONE_PARENT_SETTID). If that happened, and the core
2255 had requested the new thread to stop, we'll have
2256 killed it with SIGSTOP. But since SIGSTOP is not an
2257 RT signal, it can only be queued once. We need to be
2258 careful to not resume the LWP if we wanted it to
2259 stop. In that case, we'll leave the SIGSTOP pending.
2260 It will later be reported as TARGET_SIGNAL_0. */
2261 tp
= find_thread_ptid (new_lp
->ptid
);
2262 if (tp
!= NULL
&& tp
->stop_requested
)
2263 new_lp
->last_resume_kind
= resume_stop
;
2270 /* Add the new thread to GDB's lists as soon as possible
2273 1) the frontend doesn't have to wait for a stop to
2276 2) we tag it with the correct running state. */
2278 /* If the thread_db layer is active, let it know about
2279 this new thread, and add it to GDB's list. */
2280 if (!thread_db_attach_lwp (new_lp
->ptid
))
2282 /* We're not using thread_db. Add it to GDB's
2284 target_post_attach (GET_LWP (new_lp
->ptid
));
2285 add_thread (new_lp
->ptid
);
2290 set_running (new_lp
->ptid
, 1);
2291 set_executing (new_lp
->ptid
, 1);
2297 /* We created NEW_LP so it cannot yet contain STATUS. */
2298 gdb_assert (new_lp
->status
== 0);
2300 /* Save the wait status to report later. */
2301 if (debug_linux_nat
)
2302 fprintf_unfiltered (gdb_stdlog
,
2303 "LHEW: waitpid of new LWP %ld, "
2304 "saving status %s\n",
2305 (long) GET_LWP (new_lp
->ptid
),
2306 status_to_str (status
));
2307 new_lp
->status
= status
;
2310 /* Note the need to use the low target ops to resume, to
2311 handle resuming with PT_SYSCALL if we have syscall
2315 new_lp
->resumed
= 1;
2319 if (debug_linux_nat
)
2320 fprintf_unfiltered (gdb_stdlog
,
2321 "LHEW: resuming new LWP %ld\n",
2322 GET_LWP (new_lp
->ptid
));
2323 linux_ops
->to_resume (linux_ops
, pid_to_ptid (new_pid
),
2324 0, TARGET_SIGNAL_0
);
2325 new_lp
->stopped
= 0;
2329 if (debug_linux_nat
)
2330 fprintf_unfiltered (gdb_stdlog
,
2331 "LHEW: resuming parent LWP %d\n", pid
);
2332 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
2333 0, TARGET_SIGNAL_0
);
2341 if (event
== PTRACE_EVENT_EXEC
)
2343 if (debug_linux_nat
)
2344 fprintf_unfiltered (gdb_stdlog
,
2345 "LHEW: Got exec event from LWP %ld\n",
2346 GET_LWP (lp
->ptid
));
2348 ourstatus
->kind
= TARGET_WAITKIND_EXECD
;
2349 ourstatus
->value
.execd_pathname
2350 = xstrdup (linux_child_pid_to_exec_file (pid
));
2355 if (event
== PTRACE_EVENT_VFORK_DONE
)
2357 if (current_inferior ()->waiting_for_vfork_done
)
2359 if (debug_linux_nat
)
2360 fprintf_unfiltered (gdb_stdlog
,
2361 "LHEW: Got expected PTRACE_EVENT_"
2362 "VFORK_DONE from LWP %ld: stopping\n",
2363 GET_LWP (lp
->ptid
));
2365 ourstatus
->kind
= TARGET_WAITKIND_VFORK_DONE
;
2369 if (debug_linux_nat
)
2370 fprintf_unfiltered (gdb_stdlog
,
2371 "LHEW: Got PTRACE_EVENT_VFORK_DONE "
2372 "from LWP %ld: resuming\n",
2373 GET_LWP (lp
->ptid
));
2374 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2378 internal_error (__FILE__
, __LINE__
,
2379 _("unknown ptrace event %d"), event
);
2382 /* Return non-zero if LWP is a zombie. */
2385 linux_lwp_is_zombie (long lwp
)
2387 char buffer
[MAXPATHLEN
];
2392 xsnprintf (buffer
, sizeof (buffer
), "/proc/%ld/status", lwp
);
2393 procfile
= fopen (buffer
, "r");
2394 if (procfile
== NULL
)
2396 warning (_("unable to open /proc file '%s'"), buffer
);
2401 while (fgets (buffer
, sizeof (buffer
), procfile
) != NULL
)
2402 if (strncmp (buffer
, "State:", 6) == 0)
2407 retval
= (have_state
2408 && strcmp (buffer
, "State:\tZ (zombie)\n") == 0);
2413 /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has
2417 wait_lwp (struct lwp_info
*lp
)
2421 int thread_dead
= 0;
2424 gdb_assert (!lp
->stopped
);
2425 gdb_assert (lp
->status
== 0);
2427 /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */
2428 block_child_signals (&prev_mask
);
2432 /* If my_waitpid returns 0 it means the __WCLONE vs. non-__WCLONE kind
2433 was right and we should just call sigsuspend. */
2435 pid
= my_waitpid (GET_LWP (lp
->ptid
), &status
, WNOHANG
);
2436 if (pid
== -1 && errno
== ECHILD
)
2437 pid
= my_waitpid (GET_LWP (lp
->ptid
), &status
, __WCLONE
| WNOHANG
);
2438 if (pid
== -1 && errno
== ECHILD
)
2440 /* The thread has previously exited. We need to delete it
2441 now because, for some vendor 2.4 kernels with NPTL
2442 support backported, there won't be an exit event unless
2443 it is the main thread. 2.6 kernels will report an exit
2444 event for each thread that exits, as expected. */
2446 if (debug_linux_nat
)
2447 fprintf_unfiltered (gdb_stdlog
, "WL: %s vanished.\n",
2448 target_pid_to_str (lp
->ptid
));
2453 /* Bugs 10970, 12702.
2454 Thread group leader may have exited in which case we'll lock up in
2455 waitpid if there are other threads, even if they are all zombies too.
2456 Basically, we're not supposed to use waitpid this way.
2457 __WCLONE is not applicable for the leader so we can't use that.
2458 LINUX_NAT_THREAD_ALIVE cannot be used here as it requires a STOPPED
2459 process; it gets ESRCH both for the zombie and for running processes.
2461 As a workaround, check if we're waiting for the thread group leader and
2462 if it's a zombie, and avoid calling waitpid if it is.
2464 This is racy, what if the tgl becomes a zombie right after we check?
2465 Therefore always use WNOHANG with sigsuspend - it is equivalent to
2466 waiting waitpid but the linux_lwp_is_zombie is safe this way. */
2468 if (GET_PID (lp
->ptid
) == GET_LWP (lp
->ptid
)
2469 && linux_lwp_is_zombie (GET_LWP (lp
->ptid
)))
2472 if (debug_linux_nat
)
2473 fprintf_unfiltered (gdb_stdlog
,
2474 "WL: Thread group leader %s vanished.\n",
2475 target_pid_to_str (lp
->ptid
));
2479 /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers
2480 get invoked despite our caller had them intentionally blocked by
2481 block_child_signals. This is sensitive only to the loop of
2482 linux_nat_wait_1 and there if we get called my_waitpid gets called
2483 again before it gets to sigsuspend so we can safely let the handlers
2484 get executed here. */
2486 sigsuspend (&suspend_mask
);
2489 restore_child_signals_mask (&prev_mask
);
2493 gdb_assert (pid
== GET_LWP (lp
->ptid
));
2495 if (debug_linux_nat
)
2497 fprintf_unfiltered (gdb_stdlog
,
2498 "WL: waitpid %s received %s\n",
2499 target_pid_to_str (lp
->ptid
),
2500 status_to_str (status
));
2503 /* Check if the thread has exited. */
2504 if (WIFEXITED (status
) || WIFSIGNALED (status
))
2507 if (debug_linux_nat
)
2508 fprintf_unfiltered (gdb_stdlog
, "WL: %s exited.\n",
2509 target_pid_to_str (lp
->ptid
));
2519 gdb_assert (WIFSTOPPED (status
));
2521 /* Handle GNU/Linux's syscall SIGTRAPs. */
2522 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SYSCALL_SIGTRAP
)
2524 /* No longer need the sysgood bit. The ptrace event ends up
2525 recorded in lp->waitstatus if we care for it. We can carry
2526 on handling the event like a regular SIGTRAP from here
2528 status
= W_STOPCODE (SIGTRAP
);
2529 if (linux_handle_syscall_trap (lp
, 1))
2530 return wait_lwp (lp
);
2533 /* Handle GNU/Linux's extended waitstatus for trace events. */
2534 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
2536 if (debug_linux_nat
)
2537 fprintf_unfiltered (gdb_stdlog
,
2538 "WL: Handling extended status 0x%06x\n",
2540 if (linux_handle_extended_wait (lp
, status
, 1))
2541 return wait_lwp (lp
);
2547 /* Save the most recent siginfo for LP. This is currently only called
2548 for SIGTRAP; some ports use the si_addr field for
2549 target_stopped_data_address. In the future, it may also be used to
2550 restore the siginfo of requeued signals. */
2553 save_siginfo (struct lwp_info
*lp
)
2556 ptrace (PTRACE_GETSIGINFO
, GET_LWP (lp
->ptid
),
2557 (PTRACE_TYPE_ARG3
) 0, &lp
->siginfo
);
2560 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
2563 /* Send a SIGSTOP to LP. */
2566 stop_callback (struct lwp_info
*lp
, void *data
)
2568 if (!lp
->stopped
&& !lp
->signalled
)
2572 if (debug_linux_nat
)
2574 fprintf_unfiltered (gdb_stdlog
,
2575 "SC: kill %s **<SIGSTOP>**\n",
2576 target_pid_to_str (lp
->ptid
));
2579 ret
= kill_lwp (GET_LWP (lp
->ptid
), SIGSTOP
);
2580 if (debug_linux_nat
)
2582 fprintf_unfiltered (gdb_stdlog
,
2583 "SC: lwp kill %d %s\n",
2585 errno
? safe_strerror (errno
) : "ERRNO-OK");
2589 gdb_assert (lp
->status
== 0);
2595 /* Return non-zero if LWP PID has a pending SIGINT. */
2598 linux_nat_has_pending_sigint (int pid
)
2600 sigset_t pending
, blocked
, ignored
;
2602 linux_proc_pending_signals (pid
, &pending
, &blocked
, &ignored
);
2604 if (sigismember (&pending
, SIGINT
)
2605 && !sigismember (&ignored
, SIGINT
))
2611 /* Set a flag in LP indicating that we should ignore its next SIGINT. */
2614 set_ignore_sigint (struct lwp_info
*lp
, void *data
)
2616 /* If a thread has a pending SIGINT, consume it; otherwise, set a
2617 flag to consume the next one. */
2618 if (lp
->stopped
&& lp
->status
!= 0 && WIFSTOPPED (lp
->status
)
2619 && WSTOPSIG (lp
->status
) == SIGINT
)
2622 lp
->ignore_sigint
= 1;
2627 /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag.
2628 This function is called after we know the LWP has stopped; if the LWP
2629 stopped before the expected SIGINT was delivered, then it will never have
2630 arrived. Also, if the signal was delivered to a shared queue and consumed
2631 by a different thread, it will never be delivered to this LWP. */
2634 maybe_clear_ignore_sigint (struct lwp_info
*lp
)
2636 if (!lp
->ignore_sigint
)
2639 if (!linux_nat_has_pending_sigint (GET_LWP (lp
->ptid
)))
2641 if (debug_linux_nat
)
2642 fprintf_unfiltered (gdb_stdlog
,
2643 "MCIS: Clearing bogus flag for %s\n",
2644 target_pid_to_str (lp
->ptid
));
2645 lp
->ignore_sigint
= 0;
2649 /* Fetch the possible triggered data watchpoint info and store it in
2652 On some archs, like x86, that use debug registers to set
2653 watchpoints, it's possible that the way to know which watched
2654 address trapped, is to check the register that is used to select
2655 which address to watch. Problem is, between setting the watchpoint
2656 and reading back which data address trapped, the user may change
2657 the set of watchpoints, and, as a consequence, GDB changes the
2658 debug registers in the inferior. To avoid reading back a stale
2659 stopped-data-address when that happens, we cache in LP the fact
2660 that a watchpoint trapped, and the corresponding data address, as
2661 soon as we see LP stop with a SIGTRAP. If GDB changes the debug
2662 registers meanwhile, we have the cached data we can rely on. */
2665 save_sigtrap (struct lwp_info
*lp
)
2667 struct cleanup
*old_chain
;
2669 if (linux_ops
->to_stopped_by_watchpoint
== NULL
)
2671 lp
->stopped_by_watchpoint
= 0;
2675 old_chain
= save_inferior_ptid ();
2676 inferior_ptid
= lp
->ptid
;
2678 lp
->stopped_by_watchpoint
= linux_ops
->to_stopped_by_watchpoint ();
2680 if (lp
->stopped_by_watchpoint
)
2682 if (linux_ops
->to_stopped_data_address
!= NULL
)
2683 lp
->stopped_data_address_p
=
2684 linux_ops
->to_stopped_data_address (¤t_target
,
2685 &lp
->stopped_data_address
);
2687 lp
->stopped_data_address_p
= 0;
2690 do_cleanups (old_chain
);
2693 /* See save_sigtrap. */
2696 linux_nat_stopped_by_watchpoint (void)
2698 struct lwp_info
*lp
= find_lwp_pid (inferior_ptid
);
2700 gdb_assert (lp
!= NULL
);
2702 return lp
->stopped_by_watchpoint
;
2706 linux_nat_stopped_data_address (struct target_ops
*ops
, CORE_ADDR
*addr_p
)
2708 struct lwp_info
*lp
= find_lwp_pid (inferior_ptid
);
2710 gdb_assert (lp
!= NULL
);
2712 *addr_p
= lp
->stopped_data_address
;
2714 return lp
->stopped_data_address_p
;
2717 /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */
2720 sigtrap_is_event (int status
)
2722 return WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
;
2725 /* SIGTRAP-like events recognizer. */
2727 static int (*linux_nat_status_is_event
) (int status
) = sigtrap_is_event
;
2729 /* Check for SIGTRAP-like events in LP. */
2732 linux_nat_lp_status_is_event (struct lwp_info
*lp
)
2734 /* We check for lp->waitstatus in addition to lp->status, because we can
2735 have pending process exits recorded in lp->status
2736 and W_EXITCODE(0,0) == 0. We should probably have an additional
2737 lp->status_p flag. */
2739 return (lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
2740 && linux_nat_status_is_event (lp
->status
));
2743 /* Set alternative SIGTRAP-like events recognizer. If
2744 breakpoint_inserted_here_p there then gdbarch_decr_pc_after_break will be
2748 linux_nat_set_status_is_event (struct target_ops
*t
,
2749 int (*status_is_event
) (int status
))
2751 linux_nat_status_is_event
= status_is_event
;
2754 /* Wait until LP is stopped. */
2757 stop_wait_callback (struct lwp_info
*lp
, void *data
)
2759 struct inferior
*inf
= find_inferior_pid (GET_PID (lp
->ptid
));
2761 /* If this is a vfork parent, bail out, it is not going to report
2762 any SIGSTOP until the vfork is done with. */
2763 if (inf
->vfork_child
!= NULL
)
2770 status
= wait_lwp (lp
);
2774 if (lp
->ignore_sigint
&& WIFSTOPPED (status
)
2775 && WSTOPSIG (status
) == SIGINT
)
2777 lp
->ignore_sigint
= 0;
2780 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2781 if (debug_linux_nat
)
2782 fprintf_unfiltered (gdb_stdlog
,
2783 "PTRACE_CONT %s, 0, 0 (%s) "
2784 "(discarding SIGINT)\n",
2785 target_pid_to_str (lp
->ptid
),
2786 errno
? safe_strerror (errno
) : "OK");
2788 return stop_wait_callback (lp
, NULL
);
2791 maybe_clear_ignore_sigint (lp
);
2793 if (WSTOPSIG (status
) != SIGSTOP
)
2795 if (linux_nat_status_is_event (status
))
2797 /* If a LWP other than the LWP that we're reporting an
2798 event for has hit a GDB breakpoint (as opposed to
2799 some random trap signal), then just arrange for it to
2800 hit it again later. We don't keep the SIGTRAP status
2801 and don't forward the SIGTRAP signal to the LWP. We
2802 will handle the current event, eventually we will
2803 resume all LWPs, and this one will get its breakpoint
2806 If we do not do this, then we run the risk that the
2807 user will delete or disable the breakpoint, but the
2808 thread will have already tripped on it. */
2810 /* Save the trap's siginfo in case we need it later. */
2815 /* Now resume this LWP and get the SIGSTOP event. */
2817 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2818 if (debug_linux_nat
)
2820 fprintf_unfiltered (gdb_stdlog
,
2821 "PTRACE_CONT %s, 0, 0 (%s)\n",
2822 target_pid_to_str (lp
->ptid
),
2823 errno
? safe_strerror (errno
) : "OK");
2825 fprintf_unfiltered (gdb_stdlog
,
2826 "SWC: Candidate SIGTRAP event in %s\n",
2827 target_pid_to_str (lp
->ptid
));
2829 /* Hold this event/waitstatus while we check to see if
2830 there are any more (we still want to get that SIGSTOP). */
2831 stop_wait_callback (lp
, NULL
);
2833 /* Hold the SIGTRAP for handling by linux_nat_wait. If
2834 there's another event, throw it back into the
2838 if (debug_linux_nat
)
2839 fprintf_unfiltered (gdb_stdlog
,
2840 "SWC: kill %s, %s\n",
2841 target_pid_to_str (lp
->ptid
),
2842 status_to_str ((int) status
));
2843 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (lp
->status
));
2846 /* Save the sigtrap event. */
2847 lp
->status
= status
;
2852 /* The thread was stopped with a signal other than
2853 SIGSTOP, and didn't accidentally trip a breakpoint. */
2855 if (debug_linux_nat
)
2857 fprintf_unfiltered (gdb_stdlog
,
2858 "SWC: Pending event %s in %s\n",
2859 status_to_str ((int) status
),
2860 target_pid_to_str (lp
->ptid
));
2862 /* Now resume this LWP and get the SIGSTOP event. */
2864 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2865 if (debug_linux_nat
)
2866 fprintf_unfiltered (gdb_stdlog
,
2867 "SWC: PTRACE_CONT %s, 0, 0 (%s)\n",
2868 target_pid_to_str (lp
->ptid
),
2869 errno
? safe_strerror (errno
) : "OK");
2871 /* Hold this event/waitstatus while we check to see if
2872 there are any more (we still want to get that SIGSTOP). */
2873 stop_wait_callback (lp
, NULL
);
2875 /* If the lp->status field is still empty, use it to
2876 hold this event. If not, then this event must be
2877 returned to the event queue of the LWP. */
2880 if (debug_linux_nat
)
2882 fprintf_unfiltered (gdb_stdlog
,
2883 "SWC: kill %s, %s\n",
2884 target_pid_to_str (lp
->ptid
),
2885 status_to_str ((int) status
));
2887 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (status
));
2890 lp
->status
= status
;
2896 /* We caught the SIGSTOP that we intended to catch, so
2897 there's no SIGSTOP pending. */
2906 /* Return non-zero if LP has a wait status pending. */
2909 status_callback (struct lwp_info
*lp
, void *data
)
2911 /* Only report a pending wait status if we pretend that this has
2912 indeed been resumed. */
2916 if (lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
2918 /* A ptrace event, like PTRACE_FORK|VFORK|EXEC, syscall event,
2919 or a pending process exit. Note that `W_EXITCODE(0,0) ==
2920 0', so a clean process exit can not be stored pending in
2921 lp->status, it is indistinguishable from
2922 no-pending-status. */
2926 if (lp
->status
!= 0)
2932 /* Return non-zero if LP isn't stopped. */
2935 running_callback (struct lwp_info
*lp
, void *data
)
2937 return (!lp
->stopped
2938 || ((lp
->status
!= 0
2939 || lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
2943 /* Count the LWP's that have had events. */
2946 count_events_callback (struct lwp_info
*lp
, void *data
)
2950 gdb_assert (count
!= NULL
);
2952 /* Count only resumed LWPs that have a SIGTRAP event pending. */
2953 if (lp
->resumed
&& linux_nat_lp_status_is_event (lp
))
2959 /* Select the LWP (if any) that is currently being single-stepped. */
2962 select_singlestep_lwp_callback (struct lwp_info
*lp
, void *data
)
2964 if (lp
->last_resume_kind
== resume_step
2971 /* Select the Nth LWP that has had a SIGTRAP event. */
2974 select_event_lwp_callback (struct lwp_info
*lp
, void *data
)
2976 int *selector
= data
;
2978 gdb_assert (selector
!= NULL
);
2980 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2981 if (lp
->resumed
&& linux_nat_lp_status_is_event (lp
))
2982 if ((*selector
)-- == 0)
2989 cancel_breakpoint (struct lwp_info
*lp
)
2991 /* Arrange for a breakpoint to be hit again later. We don't keep
2992 the SIGTRAP status and don't forward the SIGTRAP signal to the
2993 LWP. We will handle the current event, eventually we will resume
2994 this LWP, and this breakpoint will trap again.
2996 If we do not do this, then we run the risk that the user will
2997 delete or disable the breakpoint, but the LWP will have already
3000 struct regcache
*regcache
= get_thread_regcache (lp
->ptid
);
3001 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3004 pc
= regcache_read_pc (regcache
) - gdbarch_decr_pc_after_break (gdbarch
);
3005 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3007 if (debug_linux_nat
)
3008 fprintf_unfiltered (gdb_stdlog
,
3009 "CB: Push back breakpoint for %s\n",
3010 target_pid_to_str (lp
->ptid
));
3012 /* Back up the PC if necessary. */
3013 if (gdbarch_decr_pc_after_break (gdbarch
))
3014 regcache_write_pc (regcache
, pc
);
3022 cancel_breakpoints_callback (struct lwp_info
*lp
, void *data
)
3024 struct lwp_info
*event_lp
= data
;
3026 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
3030 /* If a LWP other than the LWP that we're reporting an event for has
3031 hit a GDB breakpoint (as opposed to some random trap signal),
3032 then just arrange for it to hit it again later. We don't keep
3033 the SIGTRAP status and don't forward the SIGTRAP signal to the
3034 LWP. We will handle the current event, eventually we will resume
3035 all LWPs, and this one will get its breakpoint trap again.
3037 If we do not do this, then we run the risk that the user will
3038 delete or disable the breakpoint, but the LWP will have already
3041 if (linux_nat_lp_status_is_event (lp
)
3042 && cancel_breakpoint (lp
))
3043 /* Throw away the SIGTRAP. */
3049 /* Select one LWP out of those that have events pending. */
3052 select_event_lwp (ptid_t filter
, struct lwp_info
**orig_lp
, int *status
)
3055 int random_selector
;
3056 struct lwp_info
*event_lp
;
3058 /* Record the wait status for the original LWP. */
3059 (*orig_lp
)->status
= *status
;
3061 /* Give preference to any LWP that is being single-stepped. */
3062 event_lp
= iterate_over_lwps (filter
,
3063 select_singlestep_lwp_callback
, NULL
);
3064 if (event_lp
!= NULL
)
3066 if (debug_linux_nat
)
3067 fprintf_unfiltered (gdb_stdlog
,
3068 "SEL: Select single-step %s\n",
3069 target_pid_to_str (event_lp
->ptid
));
3073 /* No single-stepping LWP. Select one at random, out of those
3074 which have had SIGTRAP events. */
3076 /* First see how many SIGTRAP events we have. */
3077 iterate_over_lwps (filter
, count_events_callback
, &num_events
);
3079 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
3080 random_selector
= (int)
3081 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3083 if (debug_linux_nat
&& num_events
> 1)
3084 fprintf_unfiltered (gdb_stdlog
,
3085 "SEL: Found %d SIGTRAP events, selecting #%d\n",
3086 num_events
, random_selector
);
3088 event_lp
= iterate_over_lwps (filter
,
3089 select_event_lwp_callback
,
3093 if (event_lp
!= NULL
)
3095 /* Switch the event LWP. */
3096 *orig_lp
= event_lp
;
3097 *status
= event_lp
->status
;
3100 /* Flush the wait status for the event LWP. */
3101 (*orig_lp
)->status
= 0;
3104 /* Return non-zero if LP has been resumed. */
3107 resumed_callback (struct lwp_info
*lp
, void *data
)
3112 /* Stop an active thread, verify it still exists, then resume it. If
3113 the thread ends up with a pending status, then it is not resumed,
3114 and *DATA (really a pointer to int), is set. */
3117 stop_and_resume_callback (struct lwp_info
*lp
, void *data
)
3119 int *new_pending_p
= data
;
3123 ptid_t ptid
= lp
->ptid
;
3125 stop_callback (lp
, NULL
);
3126 stop_wait_callback (lp
, NULL
);
3128 /* Resume if the lwp still exists, and the core wanted it
3130 lp
= find_lwp_pid (ptid
);
3133 if (lp
->last_resume_kind
== resume_stop
3136 /* The core wanted the LWP to stop. Even if it stopped
3137 cleanly (with SIGSTOP), leave the event pending. */
3138 if (debug_linux_nat
)
3139 fprintf_unfiltered (gdb_stdlog
,
3140 "SARC: core wanted LWP %ld stopped "
3141 "(leaving SIGSTOP pending)\n",
3142 GET_LWP (lp
->ptid
));
3143 lp
->status
= W_STOPCODE (SIGSTOP
);
3146 if (lp
->status
== 0)
3148 if (debug_linux_nat
)
3149 fprintf_unfiltered (gdb_stdlog
,
3150 "SARC: re-resuming LWP %ld\n",
3151 GET_LWP (lp
->ptid
));
3152 resume_lwp (lp
, lp
->step
);
3156 if (debug_linux_nat
)
3157 fprintf_unfiltered (gdb_stdlog
,
3158 "SARC: not re-resuming LWP %ld "
3160 GET_LWP (lp
->ptid
));
3169 /* Check if we should go on and pass this event to common code.
3170 Return the affected lwp if we are, or NULL otherwise. If we stop
3171 all lwps temporarily, we may end up with new pending events in some
3172 other lwp. In that case set *NEW_PENDING_P to true. */
3174 static struct lwp_info
*
3175 linux_nat_filter_event (int lwpid
, int status
, int options
, int *new_pending_p
)
3177 struct lwp_info
*lp
;
3181 lp
= find_lwp_pid (pid_to_ptid (lwpid
));
3183 /* Check for stop events reported by a process we didn't already
3184 know about - anything not already in our LWP list.
3186 If we're expecting to receive stopped processes after
3187 fork, vfork, and clone events, then we'll just add the
3188 new one to our list and go back to waiting for the event
3189 to be reported - the stopped process might be returned
3190 from waitpid before or after the event is. */
3191 if (WIFSTOPPED (status
) && !lp
)
3193 add_to_pid_list (&stopped_pids
, lwpid
, status
);
3197 /* Make sure we don't report an event for the exit of an LWP not in
3198 our list, i.e. not part of the current process. This can happen
3199 if we detach from a program we originally forked and then it
3201 if (!WIFSTOPPED (status
) && !lp
)
3204 /* NOTE drow/2003-06-17: This code seems to be meant for debugging
3205 CLONE_PTRACE processes which do not use the thread library -
3206 otherwise we wouldn't find the new LWP this way. That doesn't
3207 currently work, and the following code is currently unreachable
3208 due to the two blocks above. If it's fixed some day, this code
3209 should be broken out into a function so that we can also pick up
3210 LWPs from the new interface. */
3213 lp
= add_lwp (BUILD_LWP (lwpid
, GET_PID (inferior_ptid
)));
3214 if (options
& __WCLONE
)
3217 gdb_assert (WIFSTOPPED (status
)
3218 && WSTOPSIG (status
) == SIGSTOP
);
3221 if (!in_thread_list (inferior_ptid
))
3223 inferior_ptid
= BUILD_LWP (GET_PID (inferior_ptid
),
3224 GET_PID (inferior_ptid
));
3225 add_thread (inferior_ptid
);
3228 add_thread (lp
->ptid
);
3231 /* Handle GNU/Linux's syscall SIGTRAPs. */
3232 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SYSCALL_SIGTRAP
)
3234 /* No longer need the sysgood bit. The ptrace event ends up
3235 recorded in lp->waitstatus if we care for it. We can carry
3236 on handling the event like a regular SIGTRAP from here
3238 status
= W_STOPCODE (SIGTRAP
);
3239 if (linux_handle_syscall_trap (lp
, 0))
3243 /* Handle GNU/Linux's extended waitstatus for trace events. */
3244 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
3246 if (debug_linux_nat
)
3247 fprintf_unfiltered (gdb_stdlog
,
3248 "LLW: Handling extended status 0x%06x\n",
3250 if (linux_handle_extended_wait (lp
, status
, 0))
3254 if (linux_nat_status_is_event (status
))
3256 /* Save the trap's siginfo in case we need it later. */
3262 /* Check if the thread has exited. */
3263 if ((WIFEXITED (status
) || WIFSIGNALED (status
))
3264 && num_lwps (GET_PID (lp
->ptid
)) > 1)
3266 /* If this is the main thread, we must stop all threads and verify
3267 if they are still alive. This is because in the nptl thread model
3268 on Linux 2.4, there is no signal issued for exiting LWPs
3269 other than the main thread. We only get the main thread exit
3270 signal once all child threads have already exited. If we
3271 stop all the threads and use the stop_wait_callback to check
3272 if they have exited we can determine whether this signal
3273 should be ignored or whether it means the end of the debugged
3274 application, regardless of which threading model is being
3276 if (GET_PID (lp
->ptid
) == GET_LWP (lp
->ptid
))
3279 iterate_over_lwps (pid_to_ptid (GET_PID (lp
->ptid
)),
3280 stop_and_resume_callback
, new_pending_p
);
3283 if (debug_linux_nat
)
3284 fprintf_unfiltered (gdb_stdlog
,
3285 "LLW: %s exited.\n",
3286 target_pid_to_str (lp
->ptid
));
3288 if (num_lwps (GET_PID (lp
->ptid
)) > 1)
3290 /* If there is at least one more LWP, then the exit signal
3291 was not the end of the debugged application and should be
3298 /* Check if the current LWP has previously exited. In the nptl
3299 thread model, LWPs other than the main thread do not issue
3300 signals when they exit so we must check whenever the thread has
3301 stopped. A similar check is made in stop_wait_callback(). */
3302 if (num_lwps (GET_PID (lp
->ptid
)) > 1 && !linux_thread_alive (lp
->ptid
))
3304 ptid_t ptid
= pid_to_ptid (GET_PID (lp
->ptid
));
3306 if (debug_linux_nat
)
3307 fprintf_unfiltered (gdb_stdlog
,
3308 "LLW: %s exited.\n",
3309 target_pid_to_str (lp
->ptid
));
3313 /* Make sure there is at least one thread running. */
3314 gdb_assert (iterate_over_lwps (ptid
, running_callback
, NULL
));
3316 /* Discard the event. */
3320 /* Make sure we don't report a SIGSTOP that we sent ourselves in
3321 an attempt to stop an LWP. */
3323 && WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGSTOP
)
3325 if (debug_linux_nat
)
3326 fprintf_unfiltered (gdb_stdlog
,
3327 "LLW: Delayed SIGSTOP caught for %s.\n",
3328 target_pid_to_str (lp
->ptid
));
3332 if (lp
->last_resume_kind
!= resume_stop
)
3334 /* This is a delayed SIGSTOP. */
3336 registers_changed ();
3338 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3339 lp
->step
, TARGET_SIGNAL_0
);
3340 if (debug_linux_nat
)
3341 fprintf_unfiltered (gdb_stdlog
,
3342 "LLW: %s %s, 0, 0 (discard SIGSTOP)\n",
3344 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3345 target_pid_to_str (lp
->ptid
));
3348 gdb_assert (lp
->resumed
);
3350 /* Discard the event. */
3355 /* Make sure we don't report a SIGINT that we have already displayed
3356 for another thread. */
3357 if (lp
->ignore_sigint
3358 && WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGINT
)
3360 if (debug_linux_nat
)
3361 fprintf_unfiltered (gdb_stdlog
,
3362 "LLW: Delayed SIGINT caught for %s.\n",
3363 target_pid_to_str (lp
->ptid
));
3365 /* This is a delayed SIGINT. */
3366 lp
->ignore_sigint
= 0;
3368 registers_changed ();
3369 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3370 lp
->step
, TARGET_SIGNAL_0
);
3371 if (debug_linux_nat
)
3372 fprintf_unfiltered (gdb_stdlog
,
3373 "LLW: %s %s, 0, 0 (discard SIGINT)\n",
3375 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3376 target_pid_to_str (lp
->ptid
));
3379 gdb_assert (lp
->resumed
);
3381 /* Discard the event. */
3385 /* An interesting event. */
3387 lp
->status
= status
;
3392 linux_nat_wait_1 (struct target_ops
*ops
,
3393 ptid_t ptid
, struct target_waitstatus
*ourstatus
,
3396 static sigset_t prev_mask
;
3397 enum resume_kind last_resume_kind
;
3398 struct lwp_info
*lp
;
3403 if (debug_linux_nat
)
3404 fprintf_unfiltered (gdb_stdlog
, "LLW: enter\n");
3406 /* The first time we get here after starting a new inferior, we may
3407 not have added it to the LWP list yet - this is the earliest
3408 moment at which we know its PID. */
3409 if (ptid_is_pid (inferior_ptid
))
3411 /* Upgrade the main thread's ptid. */
3412 thread_change_ptid (inferior_ptid
,
3413 BUILD_LWP (GET_PID (inferior_ptid
),
3414 GET_PID (inferior_ptid
)));
3416 lp
= add_lwp (inferior_ptid
);
3420 /* Make sure SIGCHLD is blocked. */
3421 block_child_signals (&prev_mask
);
3423 if (ptid_equal (ptid
, minus_one_ptid
))
3425 else if (ptid_is_pid (ptid
))
3426 /* A request to wait for a specific tgid. This is not possible
3427 with waitpid, so instead, we wait for any child, and leave
3428 children we're not interested in right now with a pending
3429 status to report later. */
3432 pid
= GET_LWP (ptid
);
3439 /* Make sure that of those LWPs we want to get an event from, there
3440 is at least one LWP that has been resumed. If there's none, just
3441 bail out. The core may just be flushing asynchronously all
3443 if (iterate_over_lwps (ptid
, resumed_callback
, NULL
) == NULL
)
3445 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3447 if (debug_linux_nat
)
3448 fprintf_unfiltered (gdb_stdlog
, "LLW: exit (no resumed LWP)\n");
3450 restore_child_signals_mask (&prev_mask
);
3451 return minus_one_ptid
;
3454 /* First check if there is a LWP with a wait status pending. */
3457 /* Any LWP that's been resumed will do. */
3458 lp
= iterate_over_lwps (ptid
, status_callback
, NULL
);
3461 if (debug_linux_nat
&& lp
->status
)
3462 fprintf_unfiltered (gdb_stdlog
,
3463 "LLW: Using pending wait status %s for %s.\n",
3464 status_to_str (lp
->status
),
3465 target_pid_to_str (lp
->ptid
));
3468 /* But if we don't find one, we'll have to wait, and check both
3469 cloned and uncloned processes. We start with the cloned
3471 options
= __WCLONE
| WNOHANG
;
3473 else if (is_lwp (ptid
))
3475 if (debug_linux_nat
)
3476 fprintf_unfiltered (gdb_stdlog
,
3477 "LLW: Waiting for specific LWP %s.\n",
3478 target_pid_to_str (ptid
));
3480 /* We have a specific LWP to check. */
3481 lp
= find_lwp_pid (ptid
);
3484 if (debug_linux_nat
&& lp
->status
)
3485 fprintf_unfiltered (gdb_stdlog
,
3486 "LLW: Using pending wait status %s for %s.\n",
3487 status_to_str (lp
->status
),
3488 target_pid_to_str (lp
->ptid
));
3490 /* If we have to wait, take into account whether PID is a cloned
3491 process or not. And we have to convert it to something that
3492 the layer beneath us can understand. */
3493 options
= lp
->cloned
? __WCLONE
: 0;
3494 pid
= GET_LWP (ptid
);
3496 /* We check for lp->waitstatus in addition to lp->status,
3497 because we can have pending process exits recorded in
3498 lp->status and W_EXITCODE(0,0) == 0. We should probably have
3499 an additional lp->status_p flag. */
3500 if (lp
->status
== 0 && lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
)
3504 if (lp
&& lp
->signalled
&& lp
->last_resume_kind
!= resume_stop
)
3506 /* A pending SIGSTOP may interfere with the normal stream of
3507 events. In a typical case where interference is a problem,
3508 we have a SIGSTOP signal pending for LWP A while
3509 single-stepping it, encounter an event in LWP B, and take the
3510 pending SIGSTOP while trying to stop LWP A. After processing
3511 the event in LWP B, LWP A is continued, and we'll never see
3512 the SIGTRAP associated with the last time we were
3513 single-stepping LWP A. */
3515 /* Resume the thread. It should halt immediately returning the
3517 registers_changed ();
3518 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3519 lp
->step
, TARGET_SIGNAL_0
);
3520 if (debug_linux_nat
)
3521 fprintf_unfiltered (gdb_stdlog
,
3522 "LLW: %s %s, 0, 0 (expect SIGSTOP)\n",
3523 lp
->step
? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3524 target_pid_to_str (lp
->ptid
));
3526 gdb_assert (lp
->resumed
);
3528 /* Catch the pending SIGSTOP. */
3529 status
= lp
->status
;
3532 stop_wait_callback (lp
, NULL
);
3534 /* If the lp->status field isn't empty, we caught another signal
3535 while flushing the SIGSTOP. Return it back to the event
3536 queue of the LWP, as we already have an event to handle. */
3539 if (debug_linux_nat
)
3540 fprintf_unfiltered (gdb_stdlog
,
3541 "LLW: kill %s, %s\n",
3542 target_pid_to_str (lp
->ptid
),
3543 status_to_str (lp
->status
));
3544 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (lp
->status
));
3547 lp
->status
= status
;
3550 if (!target_can_async_p ())
3552 /* Causes SIGINT to be passed on to the attached process. */
3556 /* Translate generic target_wait options into waitpid options. */
3557 if (target_options
& TARGET_WNOHANG
)
3564 lwpid
= my_waitpid (pid
, &status
, options
);
3568 /* If this is true, then we paused LWPs momentarily, and may
3569 now have pending events to handle. */
3572 gdb_assert (pid
== -1 || lwpid
== pid
);
3574 if (debug_linux_nat
)
3576 fprintf_unfiltered (gdb_stdlog
,
3577 "LLW: waitpid %ld received %s\n",
3578 (long) lwpid
, status_to_str (status
));
3581 lp
= linux_nat_filter_event (lwpid
, status
, options
, &new_pending
);
3583 /* STATUS is now no longer valid, use LP->STATUS instead. */
3587 && ptid_is_pid (ptid
)
3588 && ptid_get_pid (lp
->ptid
) != ptid_get_pid (ptid
))
3590 gdb_assert (lp
->resumed
);
3592 if (debug_linux_nat
)
3594 "LWP %ld got an event %06x, leaving pending.\n",
3595 ptid_get_lwp (lp
->ptid
), lp
->status
);
3597 if (WIFSTOPPED (lp
->status
))
3599 if (WSTOPSIG (lp
->status
) != SIGSTOP
)
3601 /* Cancel breakpoint hits. The breakpoint may
3602 be removed before we fetch events from this
3603 process to report to the core. It is best
3604 not to assume the moribund breakpoints
3605 heuristic always handles these cases --- it
3606 could be too many events go through to the
3607 core before this one is handled. All-stop
3608 always cancels breakpoint hits in all
3611 && linux_nat_lp_status_is_event (lp
)
3612 && cancel_breakpoint (lp
))
3614 /* Throw away the SIGTRAP. */
3617 if (debug_linux_nat
)
3619 "LLW: LWP %ld hit a breakpoint while"
3620 " waiting for another process;"
3622 ptid_get_lwp (lp
->ptid
));
3632 else if (WIFEXITED (lp
->status
) || WIFSIGNALED (lp
->status
))
3634 if (debug_linux_nat
)
3636 "Process %ld exited while stopping LWPs\n",
3637 ptid_get_lwp (lp
->ptid
));
3639 /* This was the last lwp in the process. Since
3640 events are serialized to GDB core, and we can't
3641 report this one right now, but GDB core and the
3642 other target layers will want to be notified
3643 about the exit code/signal, leave the status
3644 pending for the next time we're able to report
3647 /* Prevent trying to stop this thread again. We'll
3648 never try to resume it because it has a pending
3652 /* Dead LWP's aren't expected to reported a pending
3656 /* Store the pending event in the waitstatus as
3657 well, because W_EXITCODE(0,0) == 0. */
3658 store_waitstatus (&lp
->waitstatus
, lp
->status
);
3678 /* waitpid did return something. Restart over. */
3679 options
|= __WCLONE
;
3687 /* Alternate between checking cloned and uncloned processes. */
3688 options
^= __WCLONE
;
3690 /* And every time we have checked both:
3691 In async mode, return to event loop;
3692 In sync mode, suspend waiting for a SIGCHLD signal. */
3693 if (options
& __WCLONE
)
3695 if (target_options
& TARGET_WNOHANG
)
3697 /* No interesting event. */
3698 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3700 if (debug_linux_nat
)
3701 fprintf_unfiltered (gdb_stdlog
, "LLW: exit (ignore)\n");
3703 restore_child_signals_mask (&prev_mask
);
3704 return minus_one_ptid
;
3707 sigsuspend (&suspend_mask
);
3710 else if (target_options
& TARGET_WNOHANG
)
3712 /* No interesting event for PID yet. */
3713 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3715 if (debug_linux_nat
)
3716 fprintf_unfiltered (gdb_stdlog
, "LLW: exit (ignore)\n");
3718 restore_child_signals_mask (&prev_mask
);
3719 return minus_one_ptid
;
3722 /* We shouldn't end up here unless we want to try again. */
3723 gdb_assert (lp
== NULL
);
3726 if (!target_can_async_p ())
3727 clear_sigint_trap ();
3731 status
= lp
->status
;
3734 /* Don't report signals that GDB isn't interested in, such as
3735 signals that are neither printed nor stopped upon. Stopping all
3736 threads can be a bit time-consuming so if we want decent
3737 performance with heavily multi-threaded programs, especially when
3738 they're using a high frequency timer, we'd better avoid it if we
3741 if (WIFSTOPPED (status
))
3743 enum target_signal signo
= target_signal_from_host (WSTOPSIG (status
));
3745 /* When using hardware single-step, we need to report every signal.
3746 Otherwise, signals in pass_mask may be short-circuited. */
3748 && WSTOPSIG (status
) && sigismember (&pass_mask
, WSTOPSIG (status
)))
3750 /* FIMXE: kettenis/2001-06-06: Should we resume all threads
3751 here? It is not clear we should. GDB may not expect
3752 other threads to run. On the other hand, not resuming
3753 newly attached threads may cause an unwanted delay in
3754 getting them running. */
3755 registers_changed ();
3756 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3758 if (debug_linux_nat
)
3759 fprintf_unfiltered (gdb_stdlog
,
3760 "LLW: %s %s, %s (preempt 'handle')\n",
3762 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3763 target_pid_to_str (lp
->ptid
),
3764 (signo
!= TARGET_SIGNAL_0
3765 ? strsignal (target_signal_to_host (signo
))
3773 /* Only do the below in all-stop, as we currently use SIGINT
3774 to implement target_stop (see linux_nat_stop) in
3776 if (signo
== TARGET_SIGNAL_INT
&& signal_pass_state (signo
) == 0)
3778 /* If ^C/BREAK is typed at the tty/console, SIGINT gets
3779 forwarded to the entire process group, that is, all LWPs
3780 will receive it - unless they're using CLONE_THREAD to
3781 share signals. Since we only want to report it once, we
3782 mark it as ignored for all LWPs except this one. */
3783 iterate_over_lwps (pid_to_ptid (ptid_get_pid (ptid
)),
3784 set_ignore_sigint
, NULL
);
3785 lp
->ignore_sigint
= 0;
3788 maybe_clear_ignore_sigint (lp
);
3792 /* This LWP is stopped now. */
3795 if (debug_linux_nat
)
3796 fprintf_unfiltered (gdb_stdlog
, "LLW: Candidate event %s in %s.\n",
3797 status_to_str (status
), target_pid_to_str (lp
->ptid
));
3801 /* Now stop all other LWP's ... */
3802 iterate_over_lwps (minus_one_ptid
, stop_callback
, NULL
);
3804 /* ... and wait until all of them have reported back that
3805 they're no longer running. */
3806 iterate_over_lwps (minus_one_ptid
, stop_wait_callback
, NULL
);
3808 /* If we're not waiting for a specific LWP, choose an event LWP
3809 from among those that have had events. Giving equal priority
3810 to all LWPs that have had events helps prevent
3813 select_event_lwp (ptid
, &lp
, &status
);
3815 /* Now that we've selected our final event LWP, cancel any
3816 breakpoints in other LWPs that have hit a GDB breakpoint.
3817 See the comment in cancel_breakpoints_callback to find out
3819 iterate_over_lwps (minus_one_ptid
, cancel_breakpoints_callback
, lp
);
3821 /* We'll need this to determine whether to report a SIGSTOP as
3822 TARGET_WAITKIND_0. Need to take a copy because
3823 resume_clear_callback clears it. */
3824 last_resume_kind
= lp
->last_resume_kind
;
3826 /* In all-stop, from the core's perspective, all LWPs are now
3827 stopped until a new resume action is sent over. */
3828 iterate_over_lwps (minus_one_ptid
, resume_clear_callback
, NULL
);
3833 last_resume_kind
= lp
->last_resume_kind
;
3834 resume_clear_callback (lp
, NULL
);
3837 if (linux_nat_status_is_event (status
))
3839 if (debug_linux_nat
)
3840 fprintf_unfiltered (gdb_stdlog
,
3841 "LLW: trap ptid is %s.\n",
3842 target_pid_to_str (lp
->ptid
));
3845 if (lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3847 *ourstatus
= lp
->waitstatus
;
3848 lp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3851 store_waitstatus (ourstatus
, status
);
3853 if (debug_linux_nat
)
3854 fprintf_unfiltered (gdb_stdlog
, "LLW: exit\n");
3856 restore_child_signals_mask (&prev_mask
);
3858 if (last_resume_kind
== resume_stop
3859 && ourstatus
->kind
== TARGET_WAITKIND_STOPPED
3860 && WSTOPSIG (status
) == SIGSTOP
)
3862 /* A thread that has been requested to stop by GDB with
3863 target_stop, and it stopped cleanly, so report as SIG0. The
3864 use of SIGSTOP is an implementation detail. */
3865 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
3868 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
3869 || ourstatus
->kind
== TARGET_WAITKIND_SIGNALLED
)
3872 lp
->core
= linux_nat_core_of_thread_1 (lp
->ptid
);
3877 /* Resume LWPs that are currently stopped without any pending status
3878 to report, but are resumed from the core's perspective. */
3881 resume_stopped_resumed_lwps (struct lwp_info
*lp
, void *data
)
3883 ptid_t
*wait_ptid_p
= data
;
3888 && lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
)
3890 gdb_assert (is_executing (lp
->ptid
));
3892 /* Don't bother if there's a breakpoint at PC that we'd hit
3893 immediately, and we're not waiting for this LWP. */
3894 if (!ptid_match (lp
->ptid
, *wait_ptid_p
))
3896 struct regcache
*regcache
= get_thread_regcache (lp
->ptid
);
3897 CORE_ADDR pc
= regcache_read_pc (regcache
);
3899 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3903 if (debug_linux_nat
)
3904 fprintf_unfiltered (gdb_stdlog
,
3905 "RSRL: resuming stopped-resumed LWP %s\n",
3906 target_pid_to_str (lp
->ptid
));
3908 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3909 lp
->step
, TARGET_SIGNAL_0
);
3911 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
3912 lp
->stopped_by_watchpoint
= 0;
3919 linux_nat_wait (struct target_ops
*ops
,
3920 ptid_t ptid
, struct target_waitstatus
*ourstatus
,
3925 if (debug_linux_nat
)
3926 fprintf_unfiltered (gdb_stdlog
,
3927 "linux_nat_wait: [%s]\n", target_pid_to_str (ptid
));
3929 /* Flush the async file first. */
3930 if (target_can_async_p ())
3931 async_file_flush ();
3933 /* Resume LWPs that are currently stopped without any pending status
3934 to report, but are resumed from the core's perspective. LWPs get
3935 in this state if we find them stopping at a time we're not
3936 interested in reporting the event (target_wait on a
3937 specific_process, for example, see linux_nat_wait_1), and
3938 meanwhile the event became uninteresting. Don't bother resuming
3939 LWPs we're not going to wait for if they'd stop immediately. */
3941 iterate_over_lwps (minus_one_ptid
, resume_stopped_resumed_lwps
, &ptid
);
3943 event_ptid
= linux_nat_wait_1 (ops
, ptid
, ourstatus
, target_options
);
3945 /* If we requested any event, and something came out, assume there
3946 may be more. If we requested a specific lwp or process, also
3947 assume there may be more. */
3948 if (target_can_async_p ()
3949 && (ourstatus
->kind
!= TARGET_WAITKIND_IGNORE
3950 || !ptid_equal (ptid
, minus_one_ptid
)))
3953 /* Get ready for the next event. */
3954 if (target_can_async_p ())
3955 target_async (inferior_event_handler
, 0);
3961 kill_callback (struct lwp_info
*lp
, void *data
)
3963 /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */
3966 kill (GET_LWP (lp
->ptid
), SIGKILL
);
3967 if (debug_linux_nat
)
3968 fprintf_unfiltered (gdb_stdlog
,
3969 "KC: kill (SIGKILL) %s, 0, 0 (%s)\n",
3970 target_pid_to_str (lp
->ptid
),
3971 errno
? safe_strerror (errno
) : "OK");
3973 /* Some kernels ignore even SIGKILL for processes under ptrace. */
3976 ptrace (PTRACE_KILL
, GET_LWP (lp
->ptid
), 0, 0);
3977 if (debug_linux_nat
)
3978 fprintf_unfiltered (gdb_stdlog
,
3979 "KC: PTRACE_KILL %s, 0, 0 (%s)\n",
3980 target_pid_to_str (lp
->ptid
),
3981 errno
? safe_strerror (errno
) : "OK");
3987 kill_wait_callback (struct lwp_info
*lp
, void *data
)
3991 /* We must make sure that there are no pending events (delayed
3992 SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current
3993 program doesn't interfere with any following debugging session. */
3995 /* For cloned processes we must check both with __WCLONE and
3996 without, since the exit status of a cloned process isn't reported
4002 pid
= my_waitpid (GET_LWP (lp
->ptid
), NULL
, __WCLONE
);
4003 if (pid
!= (pid_t
) -1)
4005 if (debug_linux_nat
)
4006 fprintf_unfiltered (gdb_stdlog
,
4007 "KWC: wait %s received unknown.\n",
4008 target_pid_to_str (lp
->ptid
));
4009 /* The Linux kernel sometimes fails to kill a thread
4010 completely after PTRACE_KILL; that goes from the stop
4011 point in do_fork out to the one in
4012 get_signal_to_deliever and waits again. So kill it
4014 kill_callback (lp
, NULL
);
4017 while (pid
== GET_LWP (lp
->ptid
));
4019 gdb_assert (pid
== -1 && errno
== ECHILD
);
4024 pid
= my_waitpid (GET_LWP (lp
->ptid
), NULL
, 0);
4025 if (pid
!= (pid_t
) -1)
4027 if (debug_linux_nat
)
4028 fprintf_unfiltered (gdb_stdlog
,
4029 "KWC: wait %s received unk.\n",
4030 target_pid_to_str (lp
->ptid
));
4031 /* See the call to kill_callback above. */
4032 kill_callback (lp
, NULL
);
4035 while (pid
== GET_LWP (lp
->ptid
));
4037 gdb_assert (pid
== -1 && errno
== ECHILD
);
4042 linux_nat_kill (struct target_ops
*ops
)
4044 struct target_waitstatus last
;
4048 /* If we're stopped while forking and we haven't followed yet,
4049 kill the other task. We need to do this first because the
4050 parent will be sleeping if this is a vfork. */
4052 get_last_target_status (&last_ptid
, &last
);
4054 if (last
.kind
== TARGET_WAITKIND_FORKED
4055 || last
.kind
== TARGET_WAITKIND_VFORKED
)
4057 ptrace (PT_KILL
, PIDGET (last
.value
.related_pid
), 0, 0);
4061 if (forks_exist_p ())
4062 linux_fork_killall ();
4065 ptid_t ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
4067 /* Stop all threads before killing them, since ptrace requires
4068 that the thread is stopped to sucessfully PTRACE_KILL. */
4069 iterate_over_lwps (ptid
, stop_callback
, NULL
);
4070 /* ... and wait until all of them have reported back that
4071 they're no longer running. */
4072 iterate_over_lwps (ptid
, stop_wait_callback
, NULL
);
4074 /* Kill all LWP's ... */
4075 iterate_over_lwps (ptid
, kill_callback
, NULL
);
4077 /* ... and wait until we've flushed all events. */
4078 iterate_over_lwps (ptid
, kill_wait_callback
, NULL
);
4081 target_mourn_inferior ();
4085 linux_nat_mourn_inferior (struct target_ops
*ops
)
4087 purge_lwp_list (ptid_get_pid (inferior_ptid
));
4089 if (! forks_exist_p ())
4090 /* Normal case, no other forks available. */
4091 linux_ops
->to_mourn_inferior (ops
);
4093 /* Multi-fork case. The current inferior_ptid has exited, but
4094 there are other viable forks to debug. Delete the exiting
4095 one and context-switch to the first available. */
4096 linux_fork_mourn_inferior ();
4099 /* Convert a native/host siginfo object, into/from the siginfo in the
4100 layout of the inferiors' architecture. */
4103 siginfo_fixup (struct siginfo
*siginfo
, gdb_byte
*inf_siginfo
, int direction
)
4107 if (linux_nat_siginfo_fixup
!= NULL
)
4108 done
= linux_nat_siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4110 /* If there was no callback, or the callback didn't do anything,
4111 then just do a straight memcpy. */
4115 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
4117 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
4122 linux_xfer_siginfo (struct target_ops
*ops
, enum target_object object
,
4123 const char *annex
, gdb_byte
*readbuf
,
4124 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
4127 struct siginfo siginfo
;
4128 gdb_byte inf_siginfo
[sizeof (struct siginfo
)];
4130 gdb_assert (object
== TARGET_OBJECT_SIGNAL_INFO
);
4131 gdb_assert (readbuf
|| writebuf
);
4133 pid
= GET_LWP (inferior_ptid
);
4135 pid
= GET_PID (inferior_ptid
);
4137 if (offset
> sizeof (siginfo
))
4141 ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
);
4145 /* When GDB is built as a 64-bit application, ptrace writes into
4146 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4147 inferior with a 64-bit GDB should look the same as debugging it
4148 with a 32-bit GDB, we need to convert it. GDB core always sees
4149 the converted layout, so any read/write will have to be done
4151 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4153 if (offset
+ len
> sizeof (siginfo
))
4154 len
= sizeof (siginfo
) - offset
;
4156 if (readbuf
!= NULL
)
4157 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4160 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4162 /* Convert back to ptrace layout before flushing it out. */
4163 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4166 ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
);
4175 linux_nat_xfer_partial (struct target_ops
*ops
, enum target_object object
,
4176 const char *annex
, gdb_byte
*readbuf
,
4177 const gdb_byte
*writebuf
,
4178 ULONGEST offset
, LONGEST len
)
4180 struct cleanup
*old_chain
;
4183 if (object
== TARGET_OBJECT_SIGNAL_INFO
)
4184 return linux_xfer_siginfo (ops
, object
, annex
, readbuf
, writebuf
,
4187 /* The target is connected but no live inferior is selected. Pass
4188 this request down to a lower stratum (e.g., the executable
4190 if (object
== TARGET_OBJECT_MEMORY
&& ptid_equal (inferior_ptid
, null_ptid
))
4193 old_chain
= save_inferior_ptid ();
4195 if (is_lwp (inferior_ptid
))
4196 inferior_ptid
= pid_to_ptid (GET_LWP (inferior_ptid
));
4198 xfer
= linux_ops
->to_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
4201 do_cleanups (old_chain
);
4206 linux_thread_alive (ptid_t ptid
)
4210 gdb_assert (is_lwp (ptid
));
4212 /* Send signal 0 instead of anything ptrace, because ptracing a
4213 running thread errors out claiming that the thread doesn't
4215 err
= kill_lwp (GET_LWP (ptid
), 0);
4217 if (debug_linux_nat
)
4218 fprintf_unfiltered (gdb_stdlog
,
4219 "LLTA: KILL(SIG0) %s (%s)\n",
4220 target_pid_to_str (ptid
),
4221 err
? safe_strerror (tmp_errno
) : "OK");
4230 linux_nat_thread_alive (struct target_ops
*ops
, ptid_t ptid
)
4232 return linux_thread_alive (ptid
);
4236 linux_nat_pid_to_str (struct target_ops
*ops
, ptid_t ptid
)
4238 static char buf
[64];
4241 && (GET_PID (ptid
) != GET_LWP (ptid
)
4242 || num_lwps (GET_PID (ptid
)) > 1))
4244 snprintf (buf
, sizeof (buf
), "LWP %ld", GET_LWP (ptid
));
4248 return normal_pid_to_str (ptid
);
4252 linux_nat_thread_name (struct thread_info
*thr
)
4254 int pid
= ptid_get_pid (thr
->ptid
);
4255 long lwp
= ptid_get_lwp (thr
->ptid
);
4256 #define FORMAT "/proc/%d/task/%ld/comm"
4257 char buf
[sizeof (FORMAT
) + 30];
4259 char *result
= NULL
;
4261 snprintf (buf
, sizeof (buf
), FORMAT
, pid
, lwp
);
4262 comm_file
= fopen (buf
, "r");
4265 /* Not exported by the kernel, so we define it here. */
4267 static char line
[COMM_LEN
+ 1];
4269 if (fgets (line
, sizeof (line
), comm_file
))
4271 char *nl
= strchr (line
, '\n');
4288 /* Accepts an integer PID; Returns a string representing a file that
4289 can be opened to get the symbols for the child process. */
4292 linux_child_pid_to_exec_file (int pid
)
4294 char *name1
, *name2
;
4296 name1
= xmalloc (MAXPATHLEN
);
4297 name2
= xmalloc (MAXPATHLEN
);
4298 make_cleanup (xfree
, name1
);
4299 make_cleanup (xfree
, name2
);
4300 memset (name2
, 0, MAXPATHLEN
);
4302 sprintf (name1
, "/proc/%d/exe", pid
);
4303 if (readlink (name1
, name2
, MAXPATHLEN
) > 0)
4309 /* Service function for corefiles and info proc. */
4312 read_mapping (FILE *mapfile
,
4317 char *device
, long long *inode
, char *filename
)
4319 int ret
= fscanf (mapfile
, "%llx-%llx %s %llx %s %llx",
4320 addr
, endaddr
, permissions
, offset
, device
, inode
);
4323 if (ret
> 0 && ret
!= EOF
)
4325 /* Eat everything up to EOL for the filename. This will prevent
4326 weird filenames (such as one with embedded whitespace) from
4327 confusing this code. It also makes this code more robust in
4328 respect to annotations the kernel may add after the filename.
4330 Note the filename is used for informational purposes
4332 ret
+= fscanf (mapfile
, "%[^\n]\n", filename
);
4335 return (ret
!= 0 && ret
!= EOF
);
4338 /* Fills the "to_find_memory_regions" target vector. Lists the memory
4339 regions in the inferior for a corefile. */
4342 linux_nat_find_memory_regions (find_memory_region_ftype func
, void *obfd
)
4344 int pid
= PIDGET (inferior_ptid
);
4345 char mapsfilename
[MAXPATHLEN
];
4347 long long addr
, endaddr
, size
, offset
, inode
;
4348 char permissions
[8], device
[8], filename
[MAXPATHLEN
];
4349 int read
, write
, exec
;
4350 struct cleanup
*cleanup
;
4352 /* Compose the filename for the /proc memory map, and open it. */
4353 sprintf (mapsfilename
, "/proc/%d/maps", pid
);
4354 if ((mapsfile
= fopen (mapsfilename
, "r")) == NULL
)
4355 error (_("Could not open %s."), mapsfilename
);
4356 cleanup
= make_cleanup_fclose (mapsfile
);
4359 fprintf_filtered (gdb_stdout
,
4360 "Reading memory regions from %s\n", mapsfilename
);
4362 /* Now iterate until end-of-file. */
4363 while (read_mapping (mapsfile
, &addr
, &endaddr
, &permissions
[0],
4364 &offset
, &device
[0], &inode
, &filename
[0]))
4366 size
= endaddr
- addr
;
4368 /* Get the segment's permissions. */
4369 read
= (strchr (permissions
, 'r') != 0);
4370 write
= (strchr (permissions
, 'w') != 0);
4371 exec
= (strchr (permissions
, 'x') != 0);
4375 fprintf_filtered (gdb_stdout
,
4376 "Save segment, %s bytes at %s (%c%c%c)",
4377 plongest (size
), paddress (target_gdbarch
, addr
),
4379 write
? 'w' : ' ', exec
? 'x' : ' ');
4381 fprintf_filtered (gdb_stdout
, " for %s", filename
);
4382 fprintf_filtered (gdb_stdout
, "\n");
4385 /* Invoke the callback function to create the corefile
4387 func (addr
, size
, read
, write
, exec
, obfd
);
4389 do_cleanups (cleanup
);
4394 find_signalled_thread (struct thread_info
*info
, void *data
)
4396 if (info
->suspend
.stop_signal
!= TARGET_SIGNAL_0
4397 && ptid_get_pid (info
->ptid
) == ptid_get_pid (inferior_ptid
))
4403 static enum target_signal
4404 find_stop_signal (void)
4406 struct thread_info
*info
=
4407 iterate_over_threads (find_signalled_thread
, NULL
);
4410 return info
->suspend
.stop_signal
;
4412 return TARGET_SIGNAL_0
;
4415 /* Records the thread's register state for the corefile note
4419 linux_nat_do_thread_registers (bfd
*obfd
, ptid_t ptid
,
4420 char *note_data
, int *note_size
,
4421 enum target_signal stop_signal
)
4423 unsigned long lwp
= ptid_get_lwp (ptid
);
4424 struct gdbarch
*gdbarch
= target_gdbarch
;
4425 struct regcache
*regcache
= get_thread_arch_regcache (ptid
, gdbarch
);
4426 const struct regset
*regset
;
4428 struct cleanup
*old_chain
;
4429 struct core_regset_section
*sect_list
;
4432 old_chain
= save_inferior_ptid ();
4433 inferior_ptid
= ptid
;
4434 target_fetch_registers (regcache
, -1);
4435 do_cleanups (old_chain
);
4437 core_regset_p
= gdbarch_regset_from_core_section_p (gdbarch
);
4438 sect_list
= gdbarch_core_regset_sections (gdbarch
);
4440 /* The loop below uses the new struct core_regset_section, which stores
4441 the supported section names and sizes for the core file. Note that
4442 note PRSTATUS needs to be treated specially. But the other notes are
4443 structurally the same, so they can benefit from the new struct. */
4444 if (core_regset_p
&& sect_list
!= NULL
)
4445 while (sect_list
->sect_name
!= NULL
)
4447 regset
= gdbarch_regset_from_core_section (gdbarch
,
4448 sect_list
->sect_name
,
4450 gdb_assert (regset
&& regset
->collect_regset
);
4451 gdb_regset
= xmalloc (sect_list
->size
);
4452 regset
->collect_regset (regset
, regcache
, -1,
4453 gdb_regset
, sect_list
->size
);
4455 if (strcmp (sect_list
->sect_name
, ".reg") == 0)
4456 note_data
= (char *) elfcore_write_prstatus
4457 (obfd
, note_data
, note_size
,
4458 lwp
, target_signal_to_host (stop_signal
),
4461 note_data
= (char *) elfcore_write_register_note
4462 (obfd
, note_data
, note_size
,
4463 sect_list
->sect_name
, gdb_regset
,
4469 /* For architectures that does not have the struct core_regset_section
4470 implemented, we use the old method. When all the architectures have
4471 the new support, the code below should be deleted. */
4474 gdb_gregset_t gregs
;
4475 gdb_fpregset_t fpregs
;
4478 && (regset
= gdbarch_regset_from_core_section (gdbarch
, ".reg",
4480 != NULL
&& regset
->collect_regset
!= NULL
)
4481 regset
->collect_regset (regset
, regcache
, -1,
4482 &gregs
, sizeof (gregs
));
4484 fill_gregset (regcache
, &gregs
, -1);
4486 note_data
= (char *) elfcore_write_prstatus
4487 (obfd
, note_data
, note_size
, lwp
, target_signal_to_host (stop_signal
),
4491 && (regset
= gdbarch_regset_from_core_section (gdbarch
, ".reg2",
4493 != NULL
&& regset
->collect_regset
!= NULL
)
4494 regset
->collect_regset (regset
, regcache
, -1,
4495 &fpregs
, sizeof (fpregs
));
4497 fill_fpregset (regcache
, &fpregs
, -1);
4499 note_data
= (char *) elfcore_write_prfpreg (obfd
,
4502 &fpregs
, sizeof (fpregs
));
4508 struct linux_nat_corefile_thread_data
4514 enum target_signal stop_signal
;
4517 /* Called by gdbthread.c once per thread. Records the thread's
4518 register state for the corefile note section. */
4521 linux_nat_corefile_thread_callback (struct lwp_info
*ti
, void *data
)
4523 struct linux_nat_corefile_thread_data
*args
= data
;
4525 args
->note_data
= linux_nat_do_thread_registers (args
->obfd
,
4535 /* Enumerate spufs IDs for process PID. */
4538 iterate_over_spus (int pid
, void (*callback
) (void *, int), void *data
)
4542 struct dirent
*entry
;
4544 xsnprintf (path
, sizeof path
, "/proc/%d/fd", pid
);
4545 dir
= opendir (path
);
4550 while ((entry
= readdir (dir
)) != NULL
)
4556 fd
= atoi (entry
->d_name
);
4560 xsnprintf (path
, sizeof path
, "/proc/%d/fd/%d", pid
, fd
);
4561 if (stat (path
, &st
) != 0)
4563 if (!S_ISDIR (st
.st_mode
))
4566 if (statfs (path
, &stfs
) != 0)
4568 if (stfs
.f_type
!= SPUFS_MAGIC
)
4571 callback (data
, fd
);
4577 /* Generate corefile notes for SPU contexts. */
4579 struct linux_spu_corefile_data
4587 linux_spu_corefile_callback (void *data
, int fd
)
4589 struct linux_spu_corefile_data
*args
= data
;
4592 static const char *spu_files
[] =
4614 for (i
= 0; i
< sizeof (spu_files
) / sizeof (spu_files
[0]); i
++)
4616 char annex
[32], note_name
[32];
4620 xsnprintf (annex
, sizeof annex
, "%d/%s", fd
, spu_files
[i
]);
4621 spu_len
= target_read_alloc (¤t_target
, TARGET_OBJECT_SPU
,
4625 xsnprintf (note_name
, sizeof note_name
, "SPU/%s", annex
);
4626 args
->note_data
= elfcore_write_note (args
->obfd
, args
->note_data
,
4627 args
->note_size
, note_name
,
4628 NT_SPU
, spu_data
, spu_len
);
4635 linux_spu_make_corefile_notes (bfd
*obfd
, char *note_data
, int *note_size
)
4637 struct linux_spu_corefile_data args
;
4640 args
.note_data
= note_data
;
4641 args
.note_size
= note_size
;
4643 iterate_over_spus (PIDGET (inferior_ptid
),
4644 linux_spu_corefile_callback
, &args
);
4646 return args
.note_data
;
4649 /* Fills the "to_make_corefile_note" target vector. Builds the note
4650 section for a corefile, and returns it in a malloc buffer. */
4653 linux_nat_make_corefile_notes (bfd
*obfd
, int *note_size
)
4655 struct linux_nat_corefile_thread_data thread_args
;
4656 /* The variable size must be >= sizeof (prpsinfo_t.pr_fname). */
4657 char fname
[16] = { '\0' };
4658 /* The variable size must be >= sizeof (prpsinfo_t.pr_psargs). */
4659 char psargs
[80] = { '\0' };
4660 char *note_data
= NULL
;
4661 ptid_t filter
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
4665 if (get_exec_file (0))
4667 strncpy (fname
, lbasename (get_exec_file (0)), sizeof (fname
));
4668 strncpy (psargs
, get_exec_file (0), sizeof (psargs
));
4669 if (get_inferior_args ())
4672 char *psargs_end
= psargs
+ sizeof (psargs
);
4674 /* linux_elfcore_write_prpsinfo () handles zero unterminated
4676 string_end
= memchr (psargs
, 0, sizeof (psargs
));
4677 if (string_end
!= NULL
)
4679 *string_end
++ = ' ';
4680 strncpy (string_end
, get_inferior_args (),
4681 psargs_end
- string_end
);
4684 note_data
= (char *) elfcore_write_prpsinfo (obfd
,
4686 note_size
, fname
, psargs
);
4689 /* Dump information for threads. */
4690 thread_args
.obfd
= obfd
;
4691 thread_args
.note_data
= note_data
;
4692 thread_args
.note_size
= note_size
;
4693 thread_args
.num_notes
= 0;
4694 thread_args
.stop_signal
= find_stop_signal ();
4695 iterate_over_lwps (filter
, linux_nat_corefile_thread_callback
, &thread_args
);
4696 gdb_assert (thread_args
.num_notes
!= 0);
4697 note_data
= thread_args
.note_data
;
4699 auxv_len
= target_read_alloc (¤t_target
, TARGET_OBJECT_AUXV
,
4703 note_data
= elfcore_write_note (obfd
, note_data
, note_size
,
4704 "CORE", NT_AUXV
, auxv
, auxv_len
);
4708 note_data
= linux_spu_make_corefile_notes (obfd
, note_data
, note_size
);
4710 make_cleanup (xfree
, note_data
);
4714 /* Implement the "info proc" command. */
4717 linux_nat_info_proc_cmd (char *args
, int from_tty
)
4719 /* A long is used for pid instead of an int to avoid a loss of precision
4720 compiler warning from the output of strtoul. */
4721 long pid
= PIDGET (inferior_ptid
);
4724 char buffer
[MAXPATHLEN
];
4725 char fname1
[MAXPATHLEN
], fname2
[MAXPATHLEN
];
4737 /* Break up 'args' into an argv array. */
4738 argv
= gdb_buildargv (args
);
4739 make_cleanup_freeargv (argv
);
4741 while (argv
!= NULL
&& *argv
!= NULL
)
4743 if (isdigit (argv
[0][0]))
4745 pid
= strtoul (argv
[0], NULL
, 10);
4747 else if (strncmp (argv
[0], "mappings", strlen (argv
[0])) == 0)
4751 else if (strcmp (argv
[0], "status") == 0)
4755 else if (strcmp (argv
[0], "stat") == 0)
4759 else if (strcmp (argv
[0], "cmd") == 0)
4763 else if (strncmp (argv
[0], "exe", strlen (argv
[0])) == 0)
4767 else if (strcmp (argv
[0], "cwd") == 0)
4771 else if (strncmp (argv
[0], "all", strlen (argv
[0])) == 0)
4777 /* [...] (future options here). */
4782 error (_("No current process: you must name one."));
4784 sprintf (fname1
, "/proc/%ld", pid
);
4785 if (stat (fname1
, &dummy
) != 0)
4786 error (_("No /proc directory: '%s'"), fname1
);
4788 printf_filtered (_("process %ld\n"), pid
);
4789 if (cmdline_f
|| all
)
4791 sprintf (fname1
, "/proc/%ld/cmdline", pid
);
4792 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4794 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
4796 if (fgets (buffer
, sizeof (buffer
), procfile
))
4797 printf_filtered ("cmdline = '%s'\n", buffer
);
4799 warning (_("unable to read '%s'"), fname1
);
4800 do_cleanups (cleanup
);
4803 warning (_("unable to open /proc file '%s'"), fname1
);
4807 sprintf (fname1
, "/proc/%ld/cwd", pid
);
4808 memset (fname2
, 0, sizeof (fname2
));
4809 if (readlink (fname1
, fname2
, sizeof (fname2
)) > 0)
4810 printf_filtered ("cwd = '%s'\n", fname2
);
4812 warning (_("unable to read link '%s'"), fname1
);
4816 sprintf (fname1
, "/proc/%ld/exe", pid
);
4817 memset (fname2
, 0, sizeof (fname2
));
4818 if (readlink (fname1
, fname2
, sizeof (fname2
)) > 0)
4819 printf_filtered ("exe = '%s'\n", fname2
);
4821 warning (_("unable to read link '%s'"), fname1
);
4823 if (mappings_f
|| all
)
4825 sprintf (fname1
, "/proc/%ld/maps", pid
);
4826 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4828 long long addr
, endaddr
, size
, offset
, inode
;
4829 char permissions
[8], device
[8], filename
[MAXPATHLEN
];
4830 struct cleanup
*cleanup
;
4832 cleanup
= make_cleanup_fclose (procfile
);
4833 printf_filtered (_("Mapped address spaces:\n\n"));
4834 if (gdbarch_addr_bit (target_gdbarch
) == 32)
4836 printf_filtered ("\t%10s %10s %10s %10s %7s\n",
4839 " Size", " Offset", "objfile");
4843 printf_filtered (" %18s %18s %10s %10s %7s\n",
4846 " Size", " Offset", "objfile");
4849 while (read_mapping (procfile
, &addr
, &endaddr
, &permissions
[0],
4850 &offset
, &device
[0], &inode
, &filename
[0]))
4852 size
= endaddr
- addr
;
4854 /* FIXME: carlton/2003-08-27: Maybe the printf_filtered
4855 calls here (and possibly above) should be abstracted
4856 out into their own functions? Andrew suggests using
4857 a generic local_address_string instead to print out
4858 the addresses; that makes sense to me, too. */
4860 if (gdbarch_addr_bit (target_gdbarch
) == 32)
4862 printf_filtered ("\t%#10lx %#10lx %#10x %#10x %7s\n",
4863 (unsigned long) addr
, /* FIXME: pr_addr */
4864 (unsigned long) endaddr
,
4866 (unsigned int) offset
,
4867 filename
[0] ? filename
: "");
4871 printf_filtered (" %#18lx %#18lx %#10x %#10x %7s\n",
4872 (unsigned long) addr
, /* FIXME: pr_addr */
4873 (unsigned long) endaddr
,
4875 (unsigned int) offset
,
4876 filename
[0] ? filename
: "");
4880 do_cleanups (cleanup
);
4883 warning (_("unable to open /proc file '%s'"), fname1
);
4885 if (status_f
|| all
)
4887 sprintf (fname1
, "/proc/%ld/status", pid
);
4888 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4890 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
4892 while (fgets (buffer
, sizeof (buffer
), procfile
) != NULL
)
4893 puts_filtered (buffer
);
4894 do_cleanups (cleanup
);
4897 warning (_("unable to open /proc file '%s'"), fname1
);
4901 sprintf (fname1
, "/proc/%ld/stat", pid
);
4902 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4907 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
4909 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4910 printf_filtered (_("Process: %d\n"), itmp
);
4911 if (fscanf (procfile
, "(%[^)]) ", &buffer
[0]) > 0)
4912 printf_filtered (_("Exec file: %s\n"), buffer
);
4913 if (fscanf (procfile
, "%c ", &ctmp
) > 0)
4914 printf_filtered (_("State: %c\n"), ctmp
);
4915 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4916 printf_filtered (_("Parent process: %d\n"), itmp
);
4917 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4918 printf_filtered (_("Process group: %d\n"), itmp
);
4919 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4920 printf_filtered (_("Session id: %d\n"), itmp
);
4921 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4922 printf_filtered (_("TTY: %d\n"), itmp
);
4923 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4924 printf_filtered (_("TTY owner process group: %d\n"), itmp
);
4925 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4926 printf_filtered (_("Flags: 0x%lx\n"), ltmp
);
4927 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4928 printf_filtered (_("Minor faults (no memory page): %lu\n"),
4929 (unsigned long) ltmp
);
4930 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4931 printf_filtered (_("Minor faults, children: %lu\n"),
4932 (unsigned long) ltmp
);
4933 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4934 printf_filtered (_("Major faults (memory page faults): %lu\n"),
4935 (unsigned long) ltmp
);
4936 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4937 printf_filtered (_("Major faults, children: %lu\n"),
4938 (unsigned long) ltmp
);
4939 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4940 printf_filtered (_("utime: %ld\n"), ltmp
);
4941 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4942 printf_filtered (_("stime: %ld\n"), ltmp
);
4943 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4944 printf_filtered (_("utime, children: %ld\n"), ltmp
);
4945 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4946 printf_filtered (_("stime, children: %ld\n"), ltmp
);
4947 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4948 printf_filtered (_("jiffies remaining in current "
4949 "time slice: %ld\n"), ltmp
);
4950 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4951 printf_filtered (_("'nice' value: %ld\n"), ltmp
);
4952 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4953 printf_filtered (_("jiffies until next timeout: %lu\n"),
4954 (unsigned long) ltmp
);
4955 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4956 printf_filtered (_("jiffies until next SIGALRM: %lu\n"),
4957 (unsigned long) ltmp
);
4958 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4959 printf_filtered (_("start time (jiffies since "
4960 "system boot): %ld\n"), ltmp
);
4961 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4962 printf_filtered (_("Virtual memory size: %lu\n"),
4963 (unsigned long) ltmp
);
4964 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4965 printf_filtered (_("Resident set size: %lu\n"),
4966 (unsigned long) ltmp
);
4967 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4968 printf_filtered (_("rlim: %lu\n"), (unsigned long) ltmp
);
4969 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4970 printf_filtered (_("Start of text: 0x%lx\n"), ltmp
);
4971 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4972 printf_filtered (_("End of text: 0x%lx\n"), ltmp
);
4973 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4974 printf_filtered (_("Start of stack: 0x%lx\n"), ltmp
);
4975 #if 0 /* Don't know how architecture-dependent the rest is...
4976 Anyway the signal bitmap info is available from "status". */
4977 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
4978 printf_filtered (_("Kernel stack pointer: 0x%lx\n"), ltmp
);
4979 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
4980 printf_filtered (_("Kernel instr pointer: 0x%lx\n"), ltmp
);
4981 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4982 printf_filtered (_("Pending signals bitmap: 0x%lx\n"), ltmp
);
4983 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4984 printf_filtered (_("Blocked signals bitmap: 0x%lx\n"), ltmp
);
4985 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4986 printf_filtered (_("Ignored signals bitmap: 0x%lx\n"), ltmp
);
4987 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4988 printf_filtered (_("Catched signals bitmap: 0x%lx\n"), ltmp
);
4989 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
4990 printf_filtered (_("wchan (system call): 0x%lx\n"), ltmp
);
4992 do_cleanups (cleanup
);
4995 warning (_("unable to open /proc file '%s'"), fname1
);
4999 /* Implement the to_xfer_partial interface for memory reads using the /proc
5000 filesystem. Because we can use a single read() call for /proc, this
5001 can be much more efficient than banging away at PTRACE_PEEKTEXT,
5002 but it doesn't support writes. */
5005 linux_proc_xfer_partial (struct target_ops
*ops
, enum target_object object
,
5006 const char *annex
, gdb_byte
*readbuf
,
5007 const gdb_byte
*writebuf
,
5008 ULONGEST offset
, LONGEST len
)
5014 if (object
!= TARGET_OBJECT_MEMORY
|| !readbuf
)
5017 /* Don't bother for one word. */
5018 if (len
< 3 * sizeof (long))
5021 /* We could keep this file open and cache it - possibly one per
5022 thread. That requires some juggling, but is even faster. */
5023 sprintf (filename
, "/proc/%d/mem", PIDGET (inferior_ptid
));
5024 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5028 /* If pread64 is available, use it. It's faster if the kernel
5029 supports it (only one syscall), and it's 64-bit safe even on
5030 32-bit platforms (for instance, SPARC debugging a SPARC64
5033 if (pread64 (fd
, readbuf
, len
, offset
) != len
)
5035 if (lseek (fd
, offset
, SEEK_SET
) == -1 || read (fd
, readbuf
, len
) != len
)
5046 /* Enumerate spufs IDs for process PID. */
5048 spu_enumerate_spu_ids (int pid
, gdb_byte
*buf
, ULONGEST offset
, LONGEST len
)
5050 enum bfd_endian byte_order
= gdbarch_byte_order (target_gdbarch
);
5052 LONGEST written
= 0;
5055 struct dirent
*entry
;
5057 xsnprintf (path
, sizeof path
, "/proc/%d/fd", pid
);
5058 dir
= opendir (path
);
5063 while ((entry
= readdir (dir
)) != NULL
)
5069 fd
= atoi (entry
->d_name
);
5073 xsnprintf (path
, sizeof path
, "/proc/%d/fd/%d", pid
, fd
);
5074 if (stat (path
, &st
) != 0)
5076 if (!S_ISDIR (st
.st_mode
))
5079 if (statfs (path
, &stfs
) != 0)
5081 if (stfs
.f_type
!= SPUFS_MAGIC
)
5084 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
5086 store_unsigned_integer (buf
+ pos
- offset
, 4, byte_order
, fd
);
5096 /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU
5097 object type, using the /proc file system. */
5099 linux_proc_xfer_spu (struct target_ops
*ops
, enum target_object object
,
5100 const char *annex
, gdb_byte
*readbuf
,
5101 const gdb_byte
*writebuf
,
5102 ULONGEST offset
, LONGEST len
)
5107 int pid
= PIDGET (inferior_ptid
);
5114 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5117 xsnprintf (buf
, sizeof buf
, "/proc/%d/fd/%s", pid
, annex
);
5118 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5123 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5130 ret
= write (fd
, writebuf
, (size_t) len
);
5132 ret
= read (fd
, readbuf
, (size_t) len
);
5139 /* Parse LINE as a signal set and add its set bits to SIGS. */
5142 add_line_to_sigset (const char *line
, sigset_t
*sigs
)
5144 int len
= strlen (line
) - 1;
5148 if (line
[len
] != '\n')
5149 error (_("Could not parse signal set: %s"), line
);
5157 if (*p
>= '0' && *p
<= '9')
5159 else if (*p
>= 'a' && *p
<= 'f')
5160 digit
= *p
- 'a' + 10;
5162 error (_("Could not parse signal set: %s"), line
);
5167 sigaddset (sigs
, signum
+ 1);
5169 sigaddset (sigs
, signum
+ 2);
5171 sigaddset (sigs
, signum
+ 3);
5173 sigaddset (sigs
, signum
+ 4);
5179 /* Find process PID's pending signals from /proc/pid/status and set
5183 linux_proc_pending_signals (int pid
, sigset_t
*pending
,
5184 sigset_t
*blocked
, sigset_t
*ignored
)
5187 char buffer
[MAXPATHLEN
], fname
[MAXPATHLEN
];
5188 struct cleanup
*cleanup
;
5190 sigemptyset (pending
);
5191 sigemptyset (blocked
);
5192 sigemptyset (ignored
);
5193 sprintf (fname
, "/proc/%d/status", pid
);
5194 procfile
= fopen (fname
, "r");
5195 if (procfile
== NULL
)
5196 error (_("Could not open %s"), fname
);
5197 cleanup
= make_cleanup_fclose (procfile
);
5199 while (fgets (buffer
, MAXPATHLEN
, procfile
) != NULL
)
5201 /* Normal queued signals are on the SigPnd line in the status
5202 file. However, 2.6 kernels also have a "shared" pending
5203 queue for delivering signals to a thread group, so check for
5206 Unfortunately some Red Hat kernels include the shared pending
5207 queue but not the ShdPnd status field. */
5209 if (strncmp (buffer
, "SigPnd:\t", 8) == 0)
5210 add_line_to_sigset (buffer
+ 8, pending
);
5211 else if (strncmp (buffer
, "ShdPnd:\t", 8) == 0)
5212 add_line_to_sigset (buffer
+ 8, pending
);
5213 else if (strncmp (buffer
, "SigBlk:\t", 8) == 0)
5214 add_line_to_sigset (buffer
+ 8, blocked
);
5215 else if (strncmp (buffer
, "SigIgn:\t", 8) == 0)
5216 add_line_to_sigset (buffer
+ 8, ignored
);
5219 do_cleanups (cleanup
);
5223 linux_nat_xfer_osdata (struct target_ops
*ops
, enum target_object object
,
5224 const char *annex
, gdb_byte
*readbuf
,
5225 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
5227 gdb_assert (object
== TARGET_OBJECT_OSDATA
);
5229 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5233 linux_xfer_partial (struct target_ops
*ops
, enum target_object object
,
5234 const char *annex
, gdb_byte
*readbuf
,
5235 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
5239 if (object
== TARGET_OBJECT_AUXV
)
5240 return memory_xfer_auxv (ops
, object
, annex
, readbuf
, writebuf
,
5243 if (object
== TARGET_OBJECT_OSDATA
)
5244 return linux_nat_xfer_osdata (ops
, object
, annex
, readbuf
, writebuf
,
5247 if (object
== TARGET_OBJECT_SPU
)
5248 return linux_proc_xfer_spu (ops
, object
, annex
, readbuf
, writebuf
,
5251 /* GDB calculates all the addresses in possibly larget width of the address.
5252 Address width needs to be masked before its final use - either by
5253 linux_proc_xfer_partial or inf_ptrace_xfer_partial.
5255 Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */
5257 if (object
== TARGET_OBJECT_MEMORY
)
5259 int addr_bit
= gdbarch_addr_bit (target_gdbarch
);
5261 if (addr_bit
< (sizeof (ULONGEST
) * HOST_CHAR_BIT
))
5262 offset
&= ((ULONGEST
) 1 << addr_bit
) - 1;
5265 xfer
= linux_proc_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
5270 return super_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
5274 /* Create a prototype generic GNU/Linux target. The client can override
5275 it with local methods. */
5278 linux_target_install_ops (struct target_ops
*t
)
5280 t
->to_insert_fork_catchpoint
= linux_child_insert_fork_catchpoint
;
5281 t
->to_remove_fork_catchpoint
= linux_child_remove_fork_catchpoint
;
5282 t
->to_insert_vfork_catchpoint
= linux_child_insert_vfork_catchpoint
;
5283 t
->to_remove_vfork_catchpoint
= linux_child_remove_vfork_catchpoint
;
5284 t
->to_insert_exec_catchpoint
= linux_child_insert_exec_catchpoint
;
5285 t
->to_remove_exec_catchpoint
= linux_child_remove_exec_catchpoint
;
5286 t
->to_set_syscall_catchpoint
= linux_child_set_syscall_catchpoint
;
5287 t
->to_pid_to_exec_file
= linux_child_pid_to_exec_file
;
5288 t
->to_post_startup_inferior
= linux_child_post_startup_inferior
;
5289 t
->to_post_attach
= linux_child_post_attach
;
5290 t
->to_follow_fork
= linux_child_follow_fork
;
5291 t
->to_find_memory_regions
= linux_nat_find_memory_regions
;
5292 t
->to_make_corefile_notes
= linux_nat_make_corefile_notes
;
5294 super_xfer_partial
= t
->to_xfer_partial
;
5295 t
->to_xfer_partial
= linux_xfer_partial
;
5301 struct target_ops
*t
;
5303 t
= inf_ptrace_target ();
5304 linux_target_install_ops (t
);
5310 linux_trad_target (CORE_ADDR (*register_u_offset
)(struct gdbarch
*, int, int))
5312 struct target_ops
*t
;
5314 t
= inf_ptrace_trad_target (register_u_offset
);
5315 linux_target_install_ops (t
);
5320 /* target_is_async_p implementation. */
5323 linux_nat_is_async_p (void)
5325 /* NOTE: palves 2008-03-21: We're only async when the user requests
5326 it explicitly with the "set target-async" command.
5327 Someday, linux will always be async. */
5328 return target_async_permitted
;
5331 /* target_can_async_p implementation. */
5334 linux_nat_can_async_p (void)
5336 /* NOTE: palves 2008-03-21: We're only async when the user requests
5337 it explicitly with the "set target-async" command.
5338 Someday, linux will always be async. */
5339 return target_async_permitted
;
5343 linux_nat_supports_non_stop (void)
5348 /* True if we want to support multi-process. To be removed when GDB
5349 supports multi-exec. */
5351 int linux_multi_process
= 1;
5354 linux_nat_supports_multi_process (void)
5356 return linux_multi_process
;
5360 linux_nat_supports_disable_randomization (void)
5362 #ifdef HAVE_PERSONALITY
5369 static int async_terminal_is_ours
= 1;
5371 /* target_terminal_inferior implementation. */
5374 linux_nat_terminal_inferior (void)
5376 if (!target_is_async_p ())
5378 /* Async mode is disabled. */
5379 terminal_inferior ();
5383 terminal_inferior ();
5385 /* Calls to target_terminal_*() are meant to be idempotent. */
5386 if (!async_terminal_is_ours
)
5389 delete_file_handler (input_fd
);
5390 async_terminal_is_ours
= 0;
5394 /* target_terminal_ours implementation. */
5397 linux_nat_terminal_ours (void)
5399 if (!target_is_async_p ())
5401 /* Async mode is disabled. */
5406 /* GDB should never give the terminal to the inferior if the
5407 inferior is running in the background (run&, continue&, etc.),
5408 but claiming it sure should. */
5411 if (async_terminal_is_ours
)
5414 clear_sigint_trap ();
5415 add_file_handler (input_fd
, stdin_event_handler
, 0);
5416 async_terminal_is_ours
= 1;
5419 static void (*async_client_callback
) (enum inferior_event_type event_type
,
5421 static void *async_client_context
;
5423 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5424 so we notice when any child changes state, and notify the
5425 event-loop; it allows us to use sigsuspend in linux_nat_wait_1
5426 above to wait for the arrival of a SIGCHLD. */
5429 sigchld_handler (int signo
)
5431 int old_errno
= errno
;
5433 if (debug_linux_nat
)
5434 ui_file_write_async_safe (gdb_stdlog
,
5435 "sigchld\n", sizeof ("sigchld\n") - 1);
5437 if (signo
== SIGCHLD
5438 && linux_nat_event_pipe
[0] != -1)
5439 async_file_mark (); /* Let the event loop know that there are
5440 events to handle. */
5445 /* Callback registered with the target events file descriptor. */
5448 handle_target_event (int error
, gdb_client_data client_data
)
5450 (*async_client_callback
) (INF_REG_EVENT
, async_client_context
);
5453 /* Create/destroy the target events pipe. Returns previous state. */
5456 linux_async_pipe (int enable
)
5458 int previous
= (linux_nat_event_pipe
[0] != -1);
5460 if (previous
!= enable
)
5464 block_child_signals (&prev_mask
);
5468 if (pipe (linux_nat_event_pipe
) == -1)
5469 internal_error (__FILE__
, __LINE__
,
5470 "creating event pipe failed.");
5472 fcntl (linux_nat_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5473 fcntl (linux_nat_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5477 close (linux_nat_event_pipe
[0]);
5478 close (linux_nat_event_pipe
[1]);
5479 linux_nat_event_pipe
[0] = -1;
5480 linux_nat_event_pipe
[1] = -1;
5483 restore_child_signals_mask (&prev_mask
);
5489 /* target_async implementation. */
5492 linux_nat_async (void (*callback
) (enum inferior_event_type event_type
,
5493 void *context
), void *context
)
5495 if (callback
!= NULL
)
5497 async_client_callback
= callback
;
5498 async_client_context
= context
;
5499 if (!linux_async_pipe (1))
5501 add_file_handler (linux_nat_event_pipe
[0],
5502 handle_target_event
, NULL
);
5503 /* There may be pending events to handle. Tell the event loop
5510 async_client_callback
= callback
;
5511 async_client_context
= context
;
5512 delete_file_handler (linux_nat_event_pipe
[0]);
5513 linux_async_pipe (0);
5518 /* Stop an LWP, and push a TARGET_SIGNAL_0 stop status if no other
5522 linux_nat_stop_lwp (struct lwp_info
*lwp
, void *data
)
5526 ptid_t ptid
= lwp
->ptid
;
5528 if (debug_linux_nat
)
5529 fprintf_unfiltered (gdb_stdlog
,
5530 "LNSL: running -> suspending %s\n",
5531 target_pid_to_str (lwp
->ptid
));
5534 if (lwp
->last_resume_kind
== resume_stop
)
5536 if (debug_linux_nat
)
5537 fprintf_unfiltered (gdb_stdlog
,
5538 "linux-nat: already stopping LWP %ld at "
5540 ptid_get_lwp (lwp
->ptid
));
5544 stop_callback (lwp
, NULL
);
5545 lwp
->last_resume_kind
= resume_stop
;
5549 /* Already known to be stopped; do nothing. */
5551 if (debug_linux_nat
)
5553 if (find_thread_ptid (lwp
->ptid
)->stop_requested
)
5554 fprintf_unfiltered (gdb_stdlog
,
5555 "LNSL: already stopped/stop_requested %s\n",
5556 target_pid_to_str (lwp
->ptid
));
5558 fprintf_unfiltered (gdb_stdlog
,
5559 "LNSL: already stopped/no "
5560 "stop_requested yet %s\n",
5561 target_pid_to_str (lwp
->ptid
));
5568 linux_nat_stop (ptid_t ptid
)
5571 iterate_over_lwps (ptid
, linux_nat_stop_lwp
, NULL
);
5573 linux_ops
->to_stop (ptid
);
5577 linux_nat_close (int quitting
)
5579 /* Unregister from the event loop. */
5580 if (target_is_async_p ())
5581 target_async (NULL
, 0);
5583 if (linux_ops
->to_close
)
5584 linux_ops
->to_close (quitting
);
5587 /* When requests are passed down from the linux-nat layer to the
5588 single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are
5589 used. The address space pointer is stored in the inferior object,
5590 but the common code that is passed such ptid can't tell whether
5591 lwpid is a "main" process id or not (it assumes so). We reverse
5592 look up the "main" process id from the lwp here. */
5594 struct address_space
*
5595 linux_nat_thread_address_space (struct target_ops
*t
, ptid_t ptid
)
5597 struct lwp_info
*lwp
;
5598 struct inferior
*inf
;
5601 pid
= GET_LWP (ptid
);
5602 if (GET_LWP (ptid
) == 0)
5604 /* An (lwpid,0,0) ptid. Look up the lwp object to get at the
5606 lwp
= find_lwp_pid (ptid
);
5607 pid
= GET_PID (lwp
->ptid
);
5611 /* A (pid,lwpid,0) ptid. */
5612 pid
= GET_PID (ptid
);
5615 inf
= find_inferior_pid (pid
);
5616 gdb_assert (inf
!= NULL
);
5621 linux_nat_core_of_thread_1 (ptid_t ptid
)
5623 struct cleanup
*back_to
;
5626 char *content
= NULL
;
5629 int content_read
= 0;
5633 filename
= xstrprintf ("/proc/%d/task/%ld/stat",
5634 GET_PID (ptid
), GET_LWP (ptid
));
5635 back_to
= make_cleanup (xfree
, filename
);
5637 f
= fopen (filename
, "r");
5640 do_cleanups (back_to
);
5644 make_cleanup_fclose (f
);
5650 content
= xrealloc (content
, content_read
+ 1024);
5651 n
= fread (content
+ content_read
, 1, 1024, f
);
5655 content
[content_read
] = '\0';
5660 make_cleanup (xfree
, content
);
5662 p
= strchr (content
, '(');
5666 p
= strchr (p
, ')');
5670 /* If the first field after program name has index 0, then core number is
5671 the field with index 36. There's no constant for that anywhere. */
5673 p
= strtok_r (p
, " ", &ts
);
5674 for (i
= 0; p
!= NULL
&& i
!= 36; ++i
)
5675 p
= strtok_r (NULL
, " ", &ts
);
5677 if (p
== NULL
|| sscanf (p
, "%d", &core
) == 0)
5680 do_cleanups (back_to
);
5685 /* Return the cached value of the processor core for thread PTID. */
5688 linux_nat_core_of_thread (struct target_ops
*ops
, ptid_t ptid
)
5690 struct lwp_info
*info
= find_lwp_pid (ptid
);
5698 linux_nat_add_target (struct target_ops
*t
)
5700 /* Save the provided single-threaded target. We save this in a separate
5701 variable because another target we've inherited from (e.g. inf-ptrace)
5702 may have saved a pointer to T; we want to use it for the final
5703 process stratum target. */
5704 linux_ops_saved
= *t
;
5705 linux_ops
= &linux_ops_saved
;
5707 /* Override some methods for multithreading. */
5708 t
->to_create_inferior
= linux_nat_create_inferior
;
5709 t
->to_attach
= linux_nat_attach
;
5710 t
->to_detach
= linux_nat_detach
;
5711 t
->to_resume
= linux_nat_resume
;
5712 t
->to_wait
= linux_nat_wait
;
5713 t
->to_pass_signals
= linux_nat_pass_signals
;
5714 t
->to_xfer_partial
= linux_nat_xfer_partial
;
5715 t
->to_kill
= linux_nat_kill
;
5716 t
->to_mourn_inferior
= linux_nat_mourn_inferior
;
5717 t
->to_thread_alive
= linux_nat_thread_alive
;
5718 t
->to_pid_to_str
= linux_nat_pid_to_str
;
5719 t
->to_thread_name
= linux_nat_thread_name
;
5720 t
->to_has_thread_control
= tc_schedlock
;
5721 t
->to_thread_address_space
= linux_nat_thread_address_space
;
5722 t
->to_stopped_by_watchpoint
= linux_nat_stopped_by_watchpoint
;
5723 t
->to_stopped_data_address
= linux_nat_stopped_data_address
;
5725 t
->to_can_async_p
= linux_nat_can_async_p
;
5726 t
->to_is_async_p
= linux_nat_is_async_p
;
5727 t
->to_supports_non_stop
= linux_nat_supports_non_stop
;
5728 t
->to_async
= linux_nat_async
;
5729 t
->to_terminal_inferior
= linux_nat_terminal_inferior
;
5730 t
->to_terminal_ours
= linux_nat_terminal_ours
;
5731 t
->to_close
= linux_nat_close
;
5733 /* Methods for non-stop support. */
5734 t
->to_stop
= linux_nat_stop
;
5736 t
->to_supports_multi_process
= linux_nat_supports_multi_process
;
5738 t
->to_supports_disable_randomization
5739 = linux_nat_supports_disable_randomization
;
5741 t
->to_core_of_thread
= linux_nat_core_of_thread
;
5743 /* We don't change the stratum; this target will sit at
5744 process_stratum and thread_db will set at thread_stratum. This
5745 is a little strange, since this is a multi-threaded-capable
5746 target, but we want to be on the stack below thread_db, and we
5747 also want to be used for single-threaded processes. */
5752 /* Register a method to call whenever a new thread is attached. */
5754 linux_nat_set_new_thread (struct target_ops
*t
, void (*new_thread
) (ptid_t
))
5756 /* Save the pointer. We only support a single registered instance
5757 of the GNU/Linux native target, so we do not need to map this to
5759 linux_nat_new_thread
= new_thread
;
5762 /* Register a method that converts a siginfo object between the layout
5763 that ptrace returns, and the layout in the architecture of the
5766 linux_nat_set_siginfo_fixup (struct target_ops
*t
,
5767 int (*siginfo_fixup
) (struct siginfo
*,
5771 /* Save the pointer. */
5772 linux_nat_siginfo_fixup
= siginfo_fixup
;
5775 /* Return the saved siginfo associated with PTID. */
5777 linux_nat_get_siginfo (ptid_t ptid
)
5779 struct lwp_info
*lp
= find_lwp_pid (ptid
);
5781 gdb_assert (lp
!= NULL
);
5783 return &lp
->siginfo
;
5786 /* Provide a prototype to silence -Wmissing-prototypes. */
5787 extern initialize_file_ftype _initialize_linux_nat
;
5790 _initialize_linux_nat (void)
5792 add_info ("proc", linux_nat_info_proc_cmd
, _("\
5793 Show /proc process information about any running process.\n\
5794 Specify any process id, or use the program being debugged by default.\n\
5795 Specify any of the following keywords for detailed info:\n\
5796 mappings -- list of mapped memory regions.\n\
5797 stat -- list a bunch of random process info.\n\
5798 status -- list a different bunch of random process info.\n\
5799 all -- list all available /proc info."));
5801 add_setshow_zinteger_cmd ("lin-lwp", class_maintenance
,
5802 &debug_linux_nat
, _("\
5803 Set debugging of GNU/Linux lwp module."), _("\
5804 Show debugging of GNU/Linux lwp module."), _("\
5805 Enables printf debugging output."),
5807 show_debug_linux_nat
,
5808 &setdebuglist
, &showdebuglist
);
5810 /* Save this mask as the default. */
5811 sigprocmask (SIG_SETMASK
, NULL
, &normal_mask
);
5813 /* Install a SIGCHLD handler. */
5814 sigchld_action
.sa_handler
= sigchld_handler
;
5815 sigemptyset (&sigchld_action
.sa_mask
);
5816 sigchld_action
.sa_flags
= SA_RESTART
;
5818 /* Make it the default. */
5819 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
5821 /* Make sure we don't block SIGCHLD during a sigsuspend. */
5822 sigprocmask (SIG_SETMASK
, NULL
, &suspend_mask
);
5823 sigdelset (&suspend_mask
, SIGCHLD
);
5825 sigemptyset (&blocked_mask
);
5829 /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to
5830 the GNU/Linux Threads library and therefore doesn't really belong
5833 /* Read variable NAME in the target and return its value if found.
5834 Otherwise return zero. It is assumed that the type of the variable
5838 get_signo (const char *name
)
5840 struct minimal_symbol
*ms
;
5843 ms
= lookup_minimal_symbol (name
, NULL
, NULL
);
5847 if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms
), (gdb_byte
*) &signo
,
5848 sizeof (signo
)) != 0)
5854 /* Return the set of signals used by the threads library in *SET. */
5857 lin_thread_get_thread_signals (sigset_t
*set
)
5859 struct sigaction action
;
5860 int restart
, cancel
;
5862 sigemptyset (&blocked_mask
);
5865 restart
= get_signo ("__pthread_sig_restart");
5866 cancel
= get_signo ("__pthread_sig_cancel");
5868 /* LinuxThreads normally uses the first two RT signals, but in some legacy
5869 cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does
5870 not provide any way for the debugger to query the signal numbers -
5871 fortunately they don't change! */
5874 restart
= __SIGRTMIN
;
5877 cancel
= __SIGRTMIN
+ 1;
5879 sigaddset (set
, restart
);
5880 sigaddset (set
, cancel
);
5882 /* The GNU/Linux Threads library makes terminating threads send a
5883 special "cancel" signal instead of SIGCHLD. Make sure we catch
5884 those (to prevent them from terminating GDB itself, which is
5885 likely to be their default action) and treat them the same way as
5888 action
.sa_handler
= sigchld_handler
;
5889 sigemptyset (&action
.sa_mask
);
5890 action
.sa_flags
= SA_RESTART
;
5891 sigaction (cancel
, &action
, NULL
);
5893 /* We block the "cancel" signal throughout this code ... */
5894 sigaddset (&blocked_mask
, cancel
);
5895 sigprocmask (SIG_BLOCK
, &blocked_mask
, NULL
);
5897 /* ... except during a sigsuspend. */
5898 sigdelset (&suspend_mask
, cancel
);