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 check_for_thread_db ();
575 linux_enable_tracesysgood (pid_to_ptid (pid
));
579 linux_child_post_startup_inferior (ptid_t ptid
)
581 linux_enable_event_reporting (ptid
);
582 check_for_thread_db ();
583 linux_enable_tracesysgood (ptid
);
587 linux_child_follow_fork (struct target_ops
*ops
, int follow_child
)
591 int parent_pid
, child_pid
;
593 block_child_signals (&prev_mask
);
595 has_vforked
= (inferior_thread ()->pending_follow
.kind
596 == TARGET_WAITKIND_VFORKED
);
597 parent_pid
= ptid_get_lwp (inferior_ptid
);
599 parent_pid
= ptid_get_pid (inferior_ptid
);
600 child_pid
= PIDGET (inferior_thread ()->pending_follow
.value
.related_pid
);
603 linux_enable_event_reporting (pid_to_ptid (child_pid
));
606 && !non_stop
/* Non-stop always resumes both branches. */
607 && (!target_is_async_p () || sync_execution
)
608 && !(follow_child
|| detach_fork
|| sched_multi
))
610 /* The parent stays blocked inside the vfork syscall until the
611 child execs or exits. If we don't let the child run, then
612 the parent stays blocked. If we're telling the parent to run
613 in the foreground, the user will not be able to ctrl-c to get
614 back the terminal, effectively hanging the debug session. */
615 fprintf_filtered (gdb_stderr
, _("\
616 Can not resume the parent process over vfork in the foreground while\n\
617 holding the child stopped. Try \"set detach-on-fork\" or \
618 \"set schedule-multiple\".\n"));
619 /* FIXME output string > 80 columns. */
625 struct lwp_info
*child_lp
= NULL
;
627 /* We're already attached to the parent, by default. */
629 /* Detach new forked process? */
632 /* Before detaching from the child, remove all breakpoints
633 from it. If we forked, then this has already been taken
634 care of by infrun.c. If we vforked however, any
635 breakpoint inserted in the parent is visible in the
636 child, even those added while stopped in a vfork
637 catchpoint. This will remove the breakpoints from the
638 parent also, but they'll be reinserted below. */
641 /* keep breakpoints list in sync. */
642 remove_breakpoints_pid (GET_PID (inferior_ptid
));
645 if (info_verbose
|| debug_linux_nat
)
647 target_terminal_ours ();
648 fprintf_filtered (gdb_stdlog
,
649 "Detaching after fork from "
650 "child process %d.\n",
654 ptrace (PTRACE_DETACH
, child_pid
, 0, 0);
658 struct inferior
*parent_inf
, *child_inf
;
659 struct cleanup
*old_chain
;
661 /* Add process to GDB's tables. */
662 child_inf
= add_inferior (child_pid
);
664 parent_inf
= current_inferior ();
665 child_inf
->attach_flag
= parent_inf
->attach_flag
;
666 copy_terminal_info (child_inf
, parent_inf
);
668 old_chain
= save_inferior_ptid ();
669 save_current_program_space ();
671 inferior_ptid
= ptid_build (child_pid
, child_pid
, 0);
672 add_thread (inferior_ptid
);
673 child_lp
= add_lwp (inferior_ptid
);
674 child_lp
->stopped
= 1;
675 child_lp
->last_resume_kind
= resume_stop
;
677 /* If this is a vfork child, then the address-space is
678 shared with the parent. */
681 child_inf
->pspace
= parent_inf
->pspace
;
682 child_inf
->aspace
= parent_inf
->aspace
;
684 /* The parent will be frozen until the child is done
685 with the shared region. Keep track of the
687 child_inf
->vfork_parent
= parent_inf
;
688 child_inf
->pending_detach
= 0;
689 parent_inf
->vfork_child
= child_inf
;
690 parent_inf
->pending_detach
= 0;
694 child_inf
->aspace
= new_address_space ();
695 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
696 child_inf
->removable
= 1;
697 set_current_program_space (child_inf
->pspace
);
698 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
700 /* Let the shared library layer (solib-svr4) learn about
701 this new process, relocate the cloned exec, pull in
702 shared libraries, and install the solib event
703 breakpoint. If a "cloned-VM" event was propagated
704 better throughout the core, this wouldn't be
706 solib_create_inferior_hook (0);
709 /* Let the thread_db layer learn about this new process. */
710 check_for_thread_db ();
712 do_cleanups (old_chain
);
717 struct lwp_info
*parent_lp
;
718 struct inferior
*parent_inf
;
720 parent_inf
= current_inferior ();
722 /* If we detached from the child, then we have to be careful
723 to not insert breakpoints in the parent until the child
724 is done with the shared memory region. However, if we're
725 staying attached to the child, then we can and should
726 insert breakpoints, so that we can debug it. A
727 subsequent child exec or exit is enough to know when does
728 the child stops using the parent's address space. */
729 parent_inf
->waiting_for_vfork_done
= detach_fork
;
730 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
732 parent_lp
= find_lwp_pid (pid_to_ptid (parent_pid
));
733 gdb_assert (linux_supports_tracefork_flag
>= 0);
735 if (linux_supports_tracevforkdone (0))
738 fprintf_unfiltered (gdb_stdlog
,
739 "LCFF: waiting for VFORK_DONE on %d\n",
741 parent_lp
->stopped
= 1;
743 /* We'll handle the VFORK_DONE event like any other
744 event, in target_wait. */
748 /* We can't insert breakpoints until the child has
749 finished with the shared memory region. We need to
750 wait until that happens. Ideal would be to just
752 - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0);
753 - waitpid (parent_pid, &status, __WALL);
754 However, most architectures can't handle a syscall
755 being traced on the way out if it wasn't traced on
758 We might also think to loop, continuing the child
759 until it exits or gets a SIGTRAP. One problem is
760 that the child might call ptrace with PTRACE_TRACEME.
762 There's no simple and reliable way to figure out when
763 the vforked child will be done with its copy of the
764 shared memory. We could step it out of the syscall,
765 two instructions, let it go, and then single-step the
766 parent once. When we have hardware single-step, this
767 would work; with software single-step it could still
768 be made to work but we'd have to be able to insert
769 single-step breakpoints in the child, and we'd have
770 to insert -just- the single-step breakpoint in the
771 parent. Very awkward.
773 In the end, the best we can do is to make sure it
774 runs for a little while. Hopefully it will be out of
775 range of any breakpoints we reinsert. Usually this
776 is only the single-step breakpoint at vfork's return
780 fprintf_unfiltered (gdb_stdlog
,
781 "LCFF: no VFORK_DONE "
782 "support, sleeping a bit\n");
786 /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event,
787 and leave it pending. The next linux_nat_resume call
788 will notice a pending event, and bypasses actually
789 resuming the inferior. */
790 parent_lp
->status
= 0;
791 parent_lp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
792 parent_lp
->stopped
= 1;
794 /* If we're in async mode, need to tell the event loop
795 there's something here to process. */
796 if (target_can_async_p ())
803 struct inferior
*parent_inf
, *child_inf
;
804 struct lwp_info
*child_lp
;
805 struct program_space
*parent_pspace
;
807 if (info_verbose
|| debug_linux_nat
)
809 target_terminal_ours ();
811 fprintf_filtered (gdb_stdlog
,
812 _("Attaching after process %d "
813 "vfork to child process %d.\n"),
814 parent_pid
, child_pid
);
816 fprintf_filtered (gdb_stdlog
,
817 _("Attaching after process %d "
818 "fork to child process %d.\n"),
819 parent_pid
, child_pid
);
822 /* Add the new inferior first, so that the target_detach below
823 doesn't unpush the target. */
825 child_inf
= add_inferior (child_pid
);
827 parent_inf
= current_inferior ();
828 child_inf
->attach_flag
= parent_inf
->attach_flag
;
829 copy_terminal_info (child_inf
, parent_inf
);
831 parent_pspace
= parent_inf
->pspace
;
833 /* If we're vforking, we want to hold on to the parent until the
834 child exits or execs. At child exec or exit time we can
835 remove the old breakpoints from the parent and detach or
836 resume debugging it. Otherwise, detach the parent now; we'll
837 want to reuse it's program/address spaces, but we can't set
838 them to the child before removing breakpoints from the
839 parent, otherwise, the breakpoints module could decide to
840 remove breakpoints from the wrong process (since they'd be
841 assigned to the same address space). */
845 gdb_assert (child_inf
->vfork_parent
== NULL
);
846 gdb_assert (parent_inf
->vfork_child
== NULL
);
847 child_inf
->vfork_parent
= parent_inf
;
848 child_inf
->pending_detach
= 0;
849 parent_inf
->vfork_child
= child_inf
;
850 parent_inf
->pending_detach
= detach_fork
;
851 parent_inf
->waiting_for_vfork_done
= 0;
853 else if (detach_fork
)
854 target_detach (NULL
, 0);
856 /* Note that the detach above makes PARENT_INF dangling. */
858 /* Add the child thread to the appropriate lists, and switch to
859 this new thread, before cloning the program space, and
860 informing the solib layer about this new process. */
862 inferior_ptid
= ptid_build (child_pid
, child_pid
, 0);
863 add_thread (inferior_ptid
);
864 child_lp
= add_lwp (inferior_ptid
);
865 child_lp
->stopped
= 1;
866 child_lp
->last_resume_kind
= resume_stop
;
868 /* If this is a vfork child, then the address-space is shared
869 with the parent. If we detached from the parent, then we can
870 reuse the parent's program/address spaces. */
871 if (has_vforked
|| detach_fork
)
873 child_inf
->pspace
= parent_pspace
;
874 child_inf
->aspace
= child_inf
->pspace
->aspace
;
878 child_inf
->aspace
= new_address_space ();
879 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
880 child_inf
->removable
= 1;
881 set_current_program_space (child_inf
->pspace
);
882 clone_program_space (child_inf
->pspace
, parent_pspace
);
884 /* Let the shared library layer (solib-svr4) learn about
885 this new process, relocate the cloned exec, pull in
886 shared libraries, and install the solib event breakpoint.
887 If a "cloned-VM" event was propagated better throughout
888 the core, this wouldn't be required. */
889 solib_create_inferior_hook (0);
892 /* Let the thread_db layer learn about this new process. */
893 check_for_thread_db ();
896 restore_child_signals_mask (&prev_mask
);
902 linux_child_insert_fork_catchpoint (int pid
)
904 return !linux_supports_tracefork (pid
);
908 linux_child_remove_fork_catchpoint (int pid
)
914 linux_child_insert_vfork_catchpoint (int pid
)
916 return !linux_supports_tracefork (pid
);
920 linux_child_remove_vfork_catchpoint (int pid
)
926 linux_child_insert_exec_catchpoint (int pid
)
928 return !linux_supports_tracefork (pid
);
932 linux_child_remove_exec_catchpoint (int pid
)
938 linux_child_set_syscall_catchpoint (int pid
, int needed
, int any_count
,
939 int table_size
, int *table
)
941 if (!linux_supports_tracesysgood (pid
))
944 /* On GNU/Linux, we ignore the arguments. It means that we only
945 enable the syscall catchpoints, but do not disable them.
947 Also, we do not use the `table' information because we do not
948 filter system calls here. We let GDB do the logic for us. */
952 /* On GNU/Linux there are no real LWP's. The closest thing to LWP's
953 are processes sharing the same VM space. A multi-threaded process
954 is basically a group of such processes. However, such a grouping
955 is almost entirely a user-space issue; the kernel doesn't enforce
956 such a grouping at all (this might change in the future). In
957 general, we'll rely on the threads library (i.e. the GNU/Linux
958 Threads library) to provide such a grouping.
960 It is perfectly well possible to write a multi-threaded application
961 without the assistance of a threads library, by using the clone
962 system call directly. This module should be able to give some
963 rudimentary support for debugging such applications if developers
964 specify the CLONE_PTRACE flag in the clone system call, and are
965 using the Linux kernel 2.4 or above.
967 Note that there are some peculiarities in GNU/Linux that affect
970 - In general one should specify the __WCLONE flag to waitpid in
971 order to make it report events for any of the cloned processes
972 (and leave it out for the initial process). However, if a cloned
973 process has exited the exit status is only reported if the
974 __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but
975 we cannot use it since GDB must work on older systems too.
977 - When a traced, cloned process exits and is waited for by the
978 debugger, the kernel reassigns it to the original parent and
979 keeps it around as a "zombie". Somehow, the GNU/Linux Threads
980 library doesn't notice this, which leads to the "zombie problem":
981 When debugged a multi-threaded process that spawns a lot of
982 threads will run out of processes, even if the threads exit,
983 because the "zombies" stay around. */
985 /* List of known LWPs. */
986 struct lwp_info
*lwp_list
;
989 /* Original signal mask. */
990 static sigset_t normal_mask
;
992 /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in
993 _initialize_linux_nat. */
994 static sigset_t suspend_mask
;
996 /* Signals to block to make that sigsuspend work. */
997 static sigset_t blocked_mask
;
999 /* SIGCHLD action. */
1000 struct sigaction sigchld_action
;
1002 /* Block child signals (SIGCHLD and linux threads signals), and store
1003 the previous mask in PREV_MASK. */
1006 block_child_signals (sigset_t
*prev_mask
)
1008 /* Make sure SIGCHLD is blocked. */
1009 if (!sigismember (&blocked_mask
, SIGCHLD
))
1010 sigaddset (&blocked_mask
, SIGCHLD
);
1012 sigprocmask (SIG_BLOCK
, &blocked_mask
, prev_mask
);
1015 /* Restore child signals mask, previously returned by
1016 block_child_signals. */
1019 restore_child_signals_mask (sigset_t
*prev_mask
)
1021 sigprocmask (SIG_SETMASK
, prev_mask
, NULL
);
1024 /* Mask of signals to pass directly to the inferior. */
1025 static sigset_t pass_mask
;
1027 /* Update signals to pass to the inferior. */
1029 linux_nat_pass_signals (int numsigs
, unsigned char *pass_signals
)
1033 sigemptyset (&pass_mask
);
1035 for (signo
= 1; signo
< NSIG
; signo
++)
1037 int target_signo
= target_signal_from_host (signo
);
1038 if (target_signo
< numsigs
&& pass_signals
[target_signo
])
1039 sigaddset (&pass_mask
, signo
);
1045 /* Prototypes for local functions. */
1046 static int stop_wait_callback (struct lwp_info
*lp
, void *data
);
1047 static int linux_thread_alive (ptid_t ptid
);
1048 static char *linux_child_pid_to_exec_file (int pid
);
1051 /* Convert wait status STATUS to a string. Used for printing debug
1055 status_to_str (int status
)
1057 static char buf
[64];
1059 if (WIFSTOPPED (status
))
1061 if (WSTOPSIG (status
) == SYSCALL_SIGTRAP
)
1062 snprintf (buf
, sizeof (buf
), "%s (stopped at syscall)",
1063 strsignal (SIGTRAP
));
1065 snprintf (buf
, sizeof (buf
), "%s (stopped)",
1066 strsignal (WSTOPSIG (status
)));
1068 else if (WIFSIGNALED (status
))
1069 snprintf (buf
, sizeof (buf
), "%s (terminated)",
1070 strsignal (WTERMSIG (status
)));
1072 snprintf (buf
, sizeof (buf
), "%d (exited)", WEXITSTATUS (status
));
1077 /* Remove all LWPs belong to PID from the lwp list. */
1080 purge_lwp_list (int pid
)
1082 struct lwp_info
*lp
, *lpprev
, *lpnext
;
1086 for (lp
= lwp_list
; lp
; lp
= lpnext
)
1090 if (ptid_get_pid (lp
->ptid
) == pid
)
1093 lwp_list
= lp
->next
;
1095 lpprev
->next
= lp
->next
;
1104 /* Return the number of known LWPs in the tgid given by PID. */
1110 struct lwp_info
*lp
;
1112 for (lp
= lwp_list
; lp
; lp
= lp
->next
)
1113 if (ptid_get_pid (lp
->ptid
) == pid
)
1119 /* Add the LWP specified by PID to the list. Return a pointer to the
1120 structure describing the new LWP. The LWP should already be stopped
1121 (with an exception for the very first LWP). */
1123 static struct lwp_info
*
1124 add_lwp (ptid_t ptid
)
1126 struct lwp_info
*lp
;
1128 gdb_assert (is_lwp (ptid
));
1130 lp
= (struct lwp_info
*) xmalloc (sizeof (struct lwp_info
));
1132 memset (lp
, 0, sizeof (struct lwp_info
));
1134 lp
->last_resume_kind
= resume_continue
;
1135 lp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
1140 lp
->next
= lwp_list
;
1143 if (num_lwps (GET_PID (ptid
)) > 1 && linux_nat_new_thread
!= NULL
)
1144 linux_nat_new_thread (ptid
);
1149 /* Remove the LWP specified by PID from the list. */
1152 delete_lwp (ptid_t ptid
)
1154 struct lwp_info
*lp
, *lpprev
;
1158 for (lp
= lwp_list
; lp
; lpprev
= lp
, lp
= lp
->next
)
1159 if (ptid_equal (lp
->ptid
, ptid
))
1166 lpprev
->next
= lp
->next
;
1168 lwp_list
= lp
->next
;
1173 /* Return a pointer to the structure describing the LWP corresponding
1174 to PID. If no corresponding LWP could be found, return NULL. */
1176 static struct lwp_info
*
1177 find_lwp_pid (ptid_t ptid
)
1179 struct lwp_info
*lp
;
1183 lwp
= GET_LWP (ptid
);
1185 lwp
= GET_PID (ptid
);
1187 for (lp
= lwp_list
; lp
; lp
= lp
->next
)
1188 if (lwp
== GET_LWP (lp
->ptid
))
1194 /* Call CALLBACK with its second argument set to DATA for every LWP in
1195 the list. If CALLBACK returns 1 for a particular LWP, return a
1196 pointer to the structure describing that LWP immediately.
1197 Otherwise return NULL. */
1200 iterate_over_lwps (ptid_t filter
,
1201 int (*callback
) (struct lwp_info
*, void *),
1204 struct lwp_info
*lp
, *lpnext
;
1206 for (lp
= lwp_list
; lp
; lp
= lpnext
)
1210 if (ptid_match (lp
->ptid
, filter
))
1212 if ((*callback
) (lp
, data
))
1220 /* Update our internal state when changing from one checkpoint to
1221 another indicated by NEW_PTID. We can only switch single-threaded
1222 applications, so we only create one new LWP, and the previous list
1226 linux_nat_switch_fork (ptid_t new_ptid
)
1228 struct lwp_info
*lp
;
1230 purge_lwp_list (GET_PID (inferior_ptid
));
1232 lp
= add_lwp (new_ptid
);
1235 /* This changes the thread's ptid while preserving the gdb thread
1236 num. Also changes the inferior pid, while preserving the
1238 thread_change_ptid (inferior_ptid
, new_ptid
);
1240 /* We've just told GDB core that the thread changed target id, but,
1241 in fact, it really is a different thread, with different register
1243 registers_changed ();
1246 /* Handle the exit of a single thread LP. */
1249 exit_lwp (struct lwp_info
*lp
)
1251 struct thread_info
*th
= find_thread_ptid (lp
->ptid
);
1255 if (print_thread_events
)
1256 printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp
->ptid
));
1258 delete_thread (lp
->ptid
);
1261 delete_lwp (lp
->ptid
);
1264 /* Detect `T (stopped)' in `/proc/PID/status'.
1265 Other states including `T (tracing stop)' are reported as false. */
1268 pid_is_stopped (pid_t pid
)
1274 snprintf (buf
, sizeof (buf
), "/proc/%d/status", (int) pid
);
1275 status_file
= fopen (buf
, "r");
1276 if (status_file
!= NULL
)
1280 while (fgets (buf
, sizeof (buf
), status_file
))
1282 if (strncmp (buf
, "State:", 6) == 0)
1288 if (have_state
&& strstr (buf
, "T (stopped)") != NULL
)
1290 fclose (status_file
);
1295 /* Wait for the LWP specified by LP, which we have just attached to.
1296 Returns a wait status for that LWP, to cache. */
1299 linux_nat_post_attach_wait (ptid_t ptid
, int first
, int *cloned
,
1302 pid_t new_pid
, pid
= GET_LWP (ptid
);
1305 if (pid_is_stopped (pid
))
1307 if (debug_linux_nat
)
1308 fprintf_unfiltered (gdb_stdlog
,
1309 "LNPAW: Attaching to a stopped process\n");
1311 /* The process is definitely stopped. It is in a job control
1312 stop, unless the kernel predates the TASK_STOPPED /
1313 TASK_TRACED distinction, in which case it might be in a
1314 ptrace stop. Make sure it is in a ptrace stop; from there we
1315 can kill it, signal it, et cetera.
1317 First make sure there is a pending SIGSTOP. Since we are
1318 already attached, the process can not transition from stopped
1319 to running without a PTRACE_CONT; so we know this signal will
1320 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1321 probably already in the queue (unless this kernel is old
1322 enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP
1323 is not an RT signal, it can only be queued once. */
1324 kill_lwp (pid
, SIGSTOP
);
1326 /* Finally, resume the stopped process. This will deliver the SIGSTOP
1327 (or a higher priority signal, just like normal PTRACE_ATTACH). */
1328 ptrace (PTRACE_CONT
, pid
, 0, 0);
1331 /* Make sure the initial process is stopped. The user-level threads
1332 layer might want to poke around in the inferior, and that won't
1333 work if things haven't stabilized yet. */
1334 new_pid
= my_waitpid (pid
, &status
, 0);
1335 if (new_pid
== -1 && errno
== ECHILD
)
1338 warning (_("%s is a cloned process"), target_pid_to_str (ptid
));
1340 /* Try again with __WCLONE to check cloned processes. */
1341 new_pid
= my_waitpid (pid
, &status
, __WCLONE
);
1345 gdb_assert (pid
== new_pid
);
1347 if (!WIFSTOPPED (status
))
1349 /* The pid we tried to attach has apparently just exited. */
1350 if (debug_linux_nat
)
1351 fprintf_unfiltered (gdb_stdlog
, "LNPAW: Failed to stop %d: %s",
1352 pid
, status_to_str (status
));
1356 if (WSTOPSIG (status
) != SIGSTOP
)
1359 if (debug_linux_nat
)
1360 fprintf_unfiltered (gdb_stdlog
,
1361 "LNPAW: Received %s after attaching\n",
1362 status_to_str (status
));
1368 /* Attach to the LWP specified by PID. Return 0 if successful, -1 if
1369 the new LWP could not be attached, or 1 if we're already auto
1370 attached to this thread, but haven't processed the
1371 PTRACE_EVENT_CLONE event of its parent thread, so we just ignore
1372 its existance, without considering it an error. */
1375 lin_lwp_attach_lwp (ptid_t ptid
)
1377 struct lwp_info
*lp
;
1381 gdb_assert (is_lwp (ptid
));
1383 block_child_signals (&prev_mask
);
1385 lp
= find_lwp_pid (ptid
);
1386 lwpid
= GET_LWP (ptid
);
1388 /* We assume that we're already attached to any LWP that has an id
1389 equal to the overall process id, and to any LWP that is already
1390 in our list of LWPs. If we're not seeing exit events from threads
1391 and we've had PID wraparound since we last tried to stop all threads,
1392 this assumption might be wrong; fortunately, this is very unlikely
1394 if (lwpid
!= GET_PID (ptid
) && lp
== NULL
)
1396 int status
, cloned
= 0, signalled
= 0;
1398 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) < 0)
1400 if (linux_supports_tracefork_flag
)
1402 /* If we haven't stopped all threads when we get here,
1403 we may have seen a thread listed in thread_db's list,
1404 but not processed the PTRACE_EVENT_CLONE yet. If
1405 that's the case, ignore this new thread, and let
1406 normal event handling discover it later. */
1407 if (in_pid_list_p (stopped_pids
, lwpid
))
1409 /* We've already seen this thread stop, but we
1410 haven't seen the PTRACE_EVENT_CLONE extended
1412 restore_child_signals_mask (&prev_mask
);
1420 /* See if we've got a stop for this new child
1421 pending. If so, we're already attached. */
1422 new_pid
= my_waitpid (lwpid
, &status
, WNOHANG
);
1423 if (new_pid
== -1 && errno
== ECHILD
)
1424 new_pid
= my_waitpid (lwpid
, &status
, __WCLONE
| WNOHANG
);
1427 if (WIFSTOPPED (status
))
1428 add_to_pid_list (&stopped_pids
, lwpid
, status
);
1430 restore_child_signals_mask (&prev_mask
);
1436 /* If we fail to attach to the thread, issue a warning,
1437 but continue. One way this can happen is if thread
1438 creation is interrupted; as of Linux kernel 2.6.19, a
1439 bug may place threads in the thread list and then fail
1441 warning (_("Can't attach %s: %s"), target_pid_to_str (ptid
),
1442 safe_strerror (errno
));
1443 restore_child_signals_mask (&prev_mask
);
1447 if (debug_linux_nat
)
1448 fprintf_unfiltered (gdb_stdlog
,
1449 "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n",
1450 target_pid_to_str (ptid
));
1452 status
= linux_nat_post_attach_wait (ptid
, 0, &cloned
, &signalled
);
1453 if (!WIFSTOPPED (status
))
1455 restore_child_signals_mask (&prev_mask
);
1459 lp
= add_lwp (ptid
);
1461 lp
->cloned
= cloned
;
1462 lp
->signalled
= signalled
;
1463 if (WSTOPSIG (status
) != SIGSTOP
)
1466 lp
->status
= status
;
1469 target_post_attach (GET_LWP (lp
->ptid
));
1471 if (debug_linux_nat
)
1473 fprintf_unfiltered (gdb_stdlog
,
1474 "LLAL: waitpid %s received %s\n",
1475 target_pid_to_str (ptid
),
1476 status_to_str (status
));
1481 /* We assume that the LWP representing the original process is
1482 already stopped. Mark it as stopped in the data structure
1483 that the GNU/linux ptrace layer uses to keep track of
1484 threads. Note that this won't have already been done since
1485 the main thread will have, we assume, been stopped by an
1486 attach from a different layer. */
1488 lp
= add_lwp (ptid
);
1492 lp
->last_resume_kind
= resume_stop
;
1493 restore_child_signals_mask (&prev_mask
);
1498 linux_nat_create_inferior (struct target_ops
*ops
,
1499 char *exec_file
, char *allargs
, char **env
,
1502 #ifdef HAVE_PERSONALITY
1503 int personality_orig
= 0, personality_set
= 0;
1504 #endif /* HAVE_PERSONALITY */
1506 /* The fork_child mechanism is synchronous and calls target_wait, so
1507 we have to mask the async mode. */
1509 #ifdef HAVE_PERSONALITY
1510 if (disable_randomization
)
1513 personality_orig
= personality (0xffffffff);
1514 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
1516 personality_set
= 1;
1517 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
1519 if (errno
!= 0 || (personality_set
1520 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
1521 warning (_("Error disabling address space randomization: %s"),
1522 safe_strerror (errno
));
1524 #endif /* HAVE_PERSONALITY */
1526 /* Make sure we report all signals during startup. */
1527 linux_nat_pass_signals (0, NULL
);
1529 linux_ops
->to_create_inferior (ops
, exec_file
, allargs
, env
, from_tty
);
1531 #ifdef HAVE_PERSONALITY
1532 if (personality_set
)
1535 personality (personality_orig
);
1537 warning (_("Error restoring address space randomization: %s"),
1538 safe_strerror (errno
));
1540 #endif /* HAVE_PERSONALITY */
1544 linux_nat_attach (struct target_ops
*ops
, char *args
, int from_tty
)
1546 struct lwp_info
*lp
;
1550 /* Make sure we report all signals during attach. */
1551 linux_nat_pass_signals (0, NULL
);
1553 linux_ops
->to_attach (ops
, args
, from_tty
);
1555 /* The ptrace base target adds the main thread with (pid,0,0)
1556 format. Decorate it with lwp info. */
1557 ptid
= BUILD_LWP (GET_PID (inferior_ptid
), GET_PID (inferior_ptid
));
1558 thread_change_ptid (inferior_ptid
, ptid
);
1560 /* Add the initial process as the first LWP to the list. */
1561 lp
= add_lwp (ptid
);
1563 status
= linux_nat_post_attach_wait (lp
->ptid
, 1, &lp
->cloned
,
1565 if (!WIFSTOPPED (status
))
1567 if (WIFEXITED (status
))
1569 int exit_code
= WEXITSTATUS (status
);
1571 target_terminal_ours ();
1572 target_mourn_inferior ();
1574 error (_("Unable to attach: program exited normally."));
1576 error (_("Unable to attach: program exited with code %d."),
1579 else if (WIFSIGNALED (status
))
1581 enum target_signal signo
;
1583 target_terminal_ours ();
1584 target_mourn_inferior ();
1586 signo
= target_signal_from_host (WTERMSIG (status
));
1587 error (_("Unable to attach: program terminated with signal "
1589 target_signal_to_name (signo
),
1590 target_signal_to_string (signo
));
1593 internal_error (__FILE__
, __LINE__
,
1594 _("unexpected status %d for PID %ld"),
1595 status
, (long) GET_LWP (ptid
));
1600 /* Save the wait status to report later. */
1602 if (debug_linux_nat
)
1603 fprintf_unfiltered (gdb_stdlog
,
1604 "LNA: waitpid %ld, saving status %s\n",
1605 (long) GET_PID (lp
->ptid
), status_to_str (status
));
1607 lp
->status
= status
;
1609 if (target_can_async_p ())
1610 target_async (inferior_event_handler
, 0);
1613 /* Get pending status of LP. */
1615 get_pending_status (struct lwp_info
*lp
, int *status
)
1617 enum target_signal signo
= TARGET_SIGNAL_0
;
1619 /* If we paused threads momentarily, we may have stored pending
1620 events in lp->status or lp->waitstatus (see stop_wait_callback),
1621 and GDB core hasn't seen any signal for those threads.
1622 Otherwise, the last signal reported to the core is found in the
1623 thread object's stop_signal.
1625 There's a corner case that isn't handled here at present. Only
1626 if the thread stopped with a TARGET_WAITKIND_STOPPED does
1627 stop_signal make sense as a real signal to pass to the inferior.
1628 Some catchpoint related events, like
1629 TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set
1630 to TARGET_SIGNAL_SIGTRAP when the catchpoint triggers. But,
1631 those traps are debug API (ptrace in our case) related and
1632 induced; the inferior wouldn't see them if it wasn't being
1633 traced. Hence, we should never pass them to the inferior, even
1634 when set to pass state. Since this corner case isn't handled by
1635 infrun.c when proceeding with a signal, for consistency, neither
1636 do we handle it here (or elsewhere in the file we check for
1637 signal pass state). Normally SIGTRAP isn't set to pass state, so
1638 this is really a corner case. */
1640 if (lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
1641 signo
= TARGET_SIGNAL_0
; /* a pending ptrace event, not a real signal. */
1642 else if (lp
->status
)
1643 signo
= target_signal_from_host (WSTOPSIG (lp
->status
));
1644 else if (non_stop
&& !is_executing (lp
->ptid
))
1646 struct thread_info
*tp
= find_thread_ptid (lp
->ptid
);
1648 signo
= tp
->suspend
.stop_signal
;
1652 struct target_waitstatus last
;
1655 get_last_target_status (&last_ptid
, &last
);
1657 if (GET_LWP (lp
->ptid
) == GET_LWP (last_ptid
))
1659 struct thread_info
*tp
= find_thread_ptid (lp
->ptid
);
1661 signo
= tp
->suspend
.stop_signal
;
1667 if (signo
== TARGET_SIGNAL_0
)
1669 if (debug_linux_nat
)
1670 fprintf_unfiltered (gdb_stdlog
,
1671 "GPT: lwp %s has no pending signal\n",
1672 target_pid_to_str (lp
->ptid
));
1674 else if (!signal_pass_state (signo
))
1676 if (debug_linux_nat
)
1677 fprintf_unfiltered (gdb_stdlog
,
1678 "GPT: lwp %s had signal %s, "
1679 "but it is in no pass state\n",
1680 target_pid_to_str (lp
->ptid
),
1681 target_signal_to_string (signo
));
1685 *status
= W_STOPCODE (target_signal_to_host (signo
));
1687 if (debug_linux_nat
)
1688 fprintf_unfiltered (gdb_stdlog
,
1689 "GPT: lwp %s has pending signal %s\n",
1690 target_pid_to_str (lp
->ptid
),
1691 target_signal_to_string (signo
));
1698 detach_callback (struct lwp_info
*lp
, void *data
)
1700 gdb_assert (lp
->status
== 0 || WIFSTOPPED (lp
->status
));
1702 if (debug_linux_nat
&& lp
->status
)
1703 fprintf_unfiltered (gdb_stdlog
, "DC: Pending %s for %s on detach.\n",
1704 strsignal (WSTOPSIG (lp
->status
)),
1705 target_pid_to_str (lp
->ptid
));
1707 /* If there is a pending SIGSTOP, get rid of it. */
1710 if (debug_linux_nat
)
1711 fprintf_unfiltered (gdb_stdlog
,
1712 "DC: Sending SIGCONT to %s\n",
1713 target_pid_to_str (lp
->ptid
));
1715 kill_lwp (GET_LWP (lp
->ptid
), SIGCONT
);
1719 /* We don't actually detach from the LWP that has an id equal to the
1720 overall process id just yet. */
1721 if (GET_LWP (lp
->ptid
) != GET_PID (lp
->ptid
))
1725 /* Pass on any pending signal for this LWP. */
1726 get_pending_status (lp
, &status
);
1729 if (ptrace (PTRACE_DETACH
, GET_LWP (lp
->ptid
), 0,
1730 WSTOPSIG (status
)) < 0)
1731 error (_("Can't detach %s: %s"), target_pid_to_str (lp
->ptid
),
1732 safe_strerror (errno
));
1734 if (debug_linux_nat
)
1735 fprintf_unfiltered (gdb_stdlog
,
1736 "PTRACE_DETACH (%s, %s, 0) (OK)\n",
1737 target_pid_to_str (lp
->ptid
),
1738 strsignal (WSTOPSIG (status
)));
1740 delete_lwp (lp
->ptid
);
1747 linux_nat_detach (struct target_ops
*ops
, char *args
, int from_tty
)
1751 struct lwp_info
*main_lwp
;
1753 pid
= GET_PID (inferior_ptid
);
1755 if (target_can_async_p ())
1756 linux_nat_async (NULL
, 0);
1758 /* Stop all threads before detaching. ptrace requires that the
1759 thread is stopped to sucessfully detach. */
1760 iterate_over_lwps (pid_to_ptid (pid
), stop_callback
, NULL
);
1761 /* ... and wait until all of them have reported back that
1762 they're no longer running. */
1763 iterate_over_lwps (pid_to_ptid (pid
), stop_wait_callback
, NULL
);
1765 iterate_over_lwps (pid_to_ptid (pid
), detach_callback
, NULL
);
1767 /* Only the initial process should be left right now. */
1768 gdb_assert (num_lwps (GET_PID (inferior_ptid
)) == 1);
1770 main_lwp
= find_lwp_pid (pid_to_ptid (pid
));
1772 /* Pass on any pending signal for the last LWP. */
1773 if ((args
== NULL
|| *args
== '\0')
1774 && get_pending_status (main_lwp
, &status
) != -1
1775 && WIFSTOPPED (status
))
1777 /* Put the signal number in ARGS so that inf_ptrace_detach will
1778 pass it along with PTRACE_DETACH. */
1780 sprintf (args
, "%d", (int) WSTOPSIG (status
));
1781 if (debug_linux_nat
)
1782 fprintf_unfiltered (gdb_stdlog
,
1783 "LND: Sending signal %s to %s\n",
1785 target_pid_to_str (main_lwp
->ptid
));
1788 delete_lwp (main_lwp
->ptid
);
1790 if (forks_exist_p ())
1792 /* Multi-fork case. The current inferior_ptid is being detached
1793 from, but there are other viable forks to debug. Detach from
1794 the current fork, and context-switch to the first
1796 linux_fork_detach (args
, from_tty
);
1798 if (non_stop
&& target_can_async_p ())
1799 target_async (inferior_event_handler
, 0);
1802 linux_ops
->to_detach (ops
, args
, from_tty
);
1808 resume_lwp (struct lwp_info
*lp
, int step
)
1812 struct inferior
*inf
= find_inferior_pid (GET_PID (lp
->ptid
));
1814 if (inf
->vfork_child
!= NULL
)
1816 if (debug_linux_nat
)
1817 fprintf_unfiltered (gdb_stdlog
,
1818 "RC: Not resuming %s (vfork parent)\n",
1819 target_pid_to_str (lp
->ptid
));
1821 else if (lp
->status
== 0
1822 && lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
)
1824 if (debug_linux_nat
)
1825 fprintf_unfiltered (gdb_stdlog
,
1826 "RC: PTRACE_CONT %s, 0, 0 (resuming sibling)\n",
1827 target_pid_to_str (lp
->ptid
));
1829 linux_ops
->to_resume (linux_ops
,
1830 pid_to_ptid (GET_LWP (lp
->ptid
)),
1831 step
, TARGET_SIGNAL_0
);
1834 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
1835 lp
->stopped_by_watchpoint
= 0;
1839 if (debug_linux_nat
)
1840 fprintf_unfiltered (gdb_stdlog
,
1841 "RC: Not resuming sibling %s (has pending)\n",
1842 target_pid_to_str (lp
->ptid
));
1847 if (debug_linux_nat
)
1848 fprintf_unfiltered (gdb_stdlog
,
1849 "RC: Not resuming sibling %s (not stopped)\n",
1850 target_pid_to_str (lp
->ptid
));
1855 resume_callback (struct lwp_info
*lp
, void *data
)
1862 resume_clear_callback (struct lwp_info
*lp
, void *data
)
1865 lp
->last_resume_kind
= resume_stop
;
1870 resume_set_callback (struct lwp_info
*lp
, void *data
)
1873 lp
->last_resume_kind
= resume_continue
;
1878 linux_nat_resume (struct target_ops
*ops
,
1879 ptid_t ptid
, int step
, enum target_signal signo
)
1882 struct lwp_info
*lp
;
1885 if (debug_linux_nat
)
1886 fprintf_unfiltered (gdb_stdlog
,
1887 "LLR: Preparing to %s %s, %s, inferior_ptid %s\n",
1888 step
? "step" : "resume",
1889 target_pid_to_str (ptid
),
1890 (signo
!= TARGET_SIGNAL_0
1891 ? strsignal (target_signal_to_host (signo
)) : "0"),
1892 target_pid_to_str (inferior_ptid
));
1894 block_child_signals (&prev_mask
);
1896 /* A specific PTID means `step only this process id'. */
1897 resume_many
= (ptid_equal (minus_one_ptid
, ptid
)
1898 || ptid_is_pid (ptid
));
1900 /* Mark the lwps we're resuming as resumed. */
1901 iterate_over_lwps (ptid
, resume_set_callback
, NULL
);
1903 /* See if it's the current inferior that should be handled
1906 lp
= find_lwp_pid (inferior_ptid
);
1908 lp
= find_lwp_pid (ptid
);
1909 gdb_assert (lp
!= NULL
);
1911 /* Remember if we're stepping. */
1913 lp
->last_resume_kind
= step
? resume_step
: resume_continue
;
1915 /* If we have a pending wait status for this thread, there is no
1916 point in resuming the process. But first make sure that
1917 linux_nat_wait won't preemptively handle the event - we
1918 should never take this short-circuit if we are going to
1919 leave LP running, since we have skipped resuming all the
1920 other threads. This bit of code needs to be synchronized
1921 with linux_nat_wait. */
1923 if (lp
->status
&& WIFSTOPPED (lp
->status
))
1926 && WSTOPSIG (lp
->status
)
1927 && sigismember (&pass_mask
, WSTOPSIG (lp
->status
)))
1929 if (debug_linux_nat
)
1930 fprintf_unfiltered (gdb_stdlog
,
1931 "LLR: Not short circuiting for ignored "
1932 "status 0x%x\n", lp
->status
);
1934 /* FIXME: What should we do if we are supposed to continue
1935 this thread with a signal? */
1936 gdb_assert (signo
== TARGET_SIGNAL_0
);
1937 signo
= target_signal_from_host (WSTOPSIG (lp
->status
));
1942 if (lp
->status
|| lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
1944 /* FIXME: What should we do if we are supposed to continue
1945 this thread with a signal? */
1946 gdb_assert (signo
== TARGET_SIGNAL_0
);
1948 if (debug_linux_nat
)
1949 fprintf_unfiltered (gdb_stdlog
,
1950 "LLR: Short circuiting for status 0x%x\n",
1953 restore_child_signals_mask (&prev_mask
);
1954 if (target_can_async_p ())
1956 target_async (inferior_event_handler
, 0);
1957 /* Tell the event loop we have something to process. */
1963 /* Mark LWP as not stopped to prevent it from being continued by
1968 iterate_over_lwps (ptid
, resume_callback
, NULL
);
1970 /* Convert to something the lower layer understands. */
1971 ptid
= pid_to_ptid (GET_LWP (lp
->ptid
));
1973 linux_ops
->to_resume (linux_ops
, ptid
, step
, signo
);
1974 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
1975 lp
->stopped_by_watchpoint
= 0;
1977 if (debug_linux_nat
)
1978 fprintf_unfiltered (gdb_stdlog
,
1979 "LLR: %s %s, %s (resume event thread)\n",
1980 step
? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
1981 target_pid_to_str (ptid
),
1982 (signo
!= TARGET_SIGNAL_0
1983 ? strsignal (target_signal_to_host (signo
)) : "0"));
1985 restore_child_signals_mask (&prev_mask
);
1986 if (target_can_async_p ())
1987 target_async (inferior_event_handler
, 0);
1990 /* Send a signal to an LWP. */
1993 kill_lwp (int lwpid
, int signo
)
1995 /* Use tkill, if possible, in case we are using nptl threads. If tkill
1996 fails, then we are not using nptl threads and we should be using kill. */
1998 #ifdef HAVE_TKILL_SYSCALL
2000 static int tkill_failed
;
2007 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2008 if (errno
!= ENOSYS
)
2015 return kill (lwpid
, signo
);
2018 /* Handle a GNU/Linux syscall trap wait response. If we see a syscall
2019 event, check if the core is interested in it: if not, ignore the
2020 event, and keep waiting; otherwise, we need to toggle the LWP's
2021 syscall entry/exit status, since the ptrace event itself doesn't
2022 indicate it, and report the trap to higher layers. */
2025 linux_handle_syscall_trap (struct lwp_info
*lp
, int stopping
)
2027 struct target_waitstatus
*ourstatus
= &lp
->waitstatus
;
2028 struct gdbarch
*gdbarch
= target_thread_architecture (lp
->ptid
);
2029 int syscall_number
= (int) gdbarch_get_syscall_number (gdbarch
, lp
->ptid
);
2033 /* If we're stopping threads, there's a SIGSTOP pending, which
2034 makes it so that the LWP reports an immediate syscall return,
2035 followed by the SIGSTOP. Skip seeing that "return" using
2036 PTRACE_CONT directly, and let stop_wait_callback collect the
2037 SIGSTOP. Later when the thread is resumed, a new syscall
2038 entry event. If we didn't do this (and returned 0), we'd
2039 leave a syscall entry pending, and our caller, by using
2040 PTRACE_CONT to collect the SIGSTOP, skips the syscall return
2041 itself. Later, when the user re-resumes this LWP, we'd see
2042 another syscall entry event and we'd mistake it for a return.
2044 If stop_wait_callback didn't force the SIGSTOP out of the LWP
2045 (leaving immediately with LWP->signalled set, without issuing
2046 a PTRACE_CONT), it would still be problematic to leave this
2047 syscall enter pending, as later when the thread is resumed,
2048 it would then see the same syscall exit mentioned above,
2049 followed by the delayed SIGSTOP, while the syscall didn't
2050 actually get to execute. It seems it would be even more
2051 confusing to the user. */
2053 if (debug_linux_nat
)
2054 fprintf_unfiltered (gdb_stdlog
,
2055 "LHST: ignoring syscall %d "
2056 "for LWP %ld (stopping threads), "
2057 "resuming with PTRACE_CONT for SIGSTOP\n",
2059 GET_LWP (lp
->ptid
));
2061 lp
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2062 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2066 if (catch_syscall_enabled ())
2068 /* Always update the entry/return state, even if this particular
2069 syscall isn't interesting to the core now. In async mode,
2070 the user could install a new catchpoint for this syscall
2071 between syscall enter/return, and we'll need to know to
2072 report a syscall return if that happens. */
2073 lp
->syscall_state
= (lp
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2074 ? TARGET_WAITKIND_SYSCALL_RETURN
2075 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2077 if (catching_syscall_number (syscall_number
))
2079 /* Alright, an event to report. */
2080 ourstatus
->kind
= lp
->syscall_state
;
2081 ourstatus
->value
.syscall_number
= syscall_number
;
2083 if (debug_linux_nat
)
2084 fprintf_unfiltered (gdb_stdlog
,
2085 "LHST: stopping for %s of syscall %d"
2088 == TARGET_WAITKIND_SYSCALL_ENTRY
2089 ? "entry" : "return",
2091 GET_LWP (lp
->ptid
));
2095 if (debug_linux_nat
)
2096 fprintf_unfiltered (gdb_stdlog
,
2097 "LHST: ignoring %s of syscall %d "
2099 lp
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2100 ? "entry" : "return",
2102 GET_LWP (lp
->ptid
));
2106 /* If we had been syscall tracing, and hence used PT_SYSCALL
2107 before on this LWP, it could happen that the user removes all
2108 syscall catchpoints before we get to process this event.
2109 There are two noteworthy issues here:
2111 - When stopped at a syscall entry event, resuming with
2112 PT_STEP still resumes executing the syscall and reports a
2115 - Only PT_SYSCALL catches syscall enters. If we last
2116 single-stepped this thread, then this event can't be a
2117 syscall enter. If we last single-stepped this thread, this
2118 has to be a syscall exit.
2120 The points above mean that the next resume, be it PT_STEP or
2121 PT_CONTINUE, can not trigger a syscall trace event. */
2122 if (debug_linux_nat
)
2123 fprintf_unfiltered (gdb_stdlog
,
2124 "LHST: caught syscall event "
2125 "with no syscall catchpoints."
2126 " %d for LWP %ld, ignoring\n",
2128 GET_LWP (lp
->ptid
));
2129 lp
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2132 /* The core isn't interested in this event. For efficiency, avoid
2133 stopping all threads only to have the core resume them all again.
2134 Since we're not stopping threads, if we're still syscall tracing
2135 and not stepping, we can't use PTRACE_CONT here, as we'd miss any
2136 subsequent syscall. Simply resume using the inf-ptrace layer,
2137 which knows when to use PT_SYSCALL or PT_CONTINUE. */
2139 /* Note that gdbarch_get_syscall_number may access registers, hence
2141 registers_changed ();
2142 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
2143 lp
->step
, TARGET_SIGNAL_0
);
2147 /* Handle a GNU/Linux extended wait response. If we see a clone
2148 event, we need to add the new LWP to our list (and not report the
2149 trap to higher layers). This function returns non-zero if the
2150 event should be ignored and we should wait again. If STOPPING is
2151 true, the new LWP remains stopped, otherwise it is continued. */
2154 linux_handle_extended_wait (struct lwp_info
*lp
, int status
,
2157 int pid
= GET_LWP (lp
->ptid
);
2158 struct target_waitstatus
*ourstatus
= &lp
->waitstatus
;
2159 int event
= status
>> 16;
2161 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
2162 || event
== PTRACE_EVENT_CLONE
)
2164 unsigned long new_pid
;
2167 ptrace (PTRACE_GETEVENTMSG
, pid
, 0, &new_pid
);
2169 /* If we haven't already seen the new PID stop, wait for it now. */
2170 if (! pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
2172 /* The new child has a pending SIGSTOP. We can't affect it until it
2173 hits the SIGSTOP, but we're already attached. */
2174 ret
= my_waitpid (new_pid
, &status
,
2175 (event
== PTRACE_EVENT_CLONE
) ? __WCLONE
: 0);
2177 perror_with_name (_("waiting for new child"));
2178 else if (ret
!= new_pid
)
2179 internal_error (__FILE__
, __LINE__
,
2180 _("wait returned unexpected PID %d"), ret
);
2181 else if (!WIFSTOPPED (status
))
2182 internal_error (__FILE__
, __LINE__
,
2183 _("wait returned unexpected status 0x%x"), status
);
2186 ourstatus
->value
.related_pid
= ptid_build (new_pid
, new_pid
, 0);
2188 if (event
== PTRACE_EVENT_FORK
2189 && linux_fork_checkpointing_p (GET_PID (lp
->ptid
)))
2191 /* Handle checkpointing by linux-fork.c here as a special
2192 case. We don't want the follow-fork-mode or 'catch fork'
2193 to interfere with this. */
2195 /* This won't actually modify the breakpoint list, but will
2196 physically remove the breakpoints from the child. */
2197 detach_breakpoints (new_pid
);
2199 /* Retain child fork in ptrace (stopped) state. */
2200 if (!find_fork_pid (new_pid
))
2203 /* Report as spurious, so that infrun doesn't want to follow
2204 this fork. We're actually doing an infcall in
2206 ourstatus
->kind
= TARGET_WAITKIND_SPURIOUS
;
2207 linux_enable_event_reporting (pid_to_ptid (new_pid
));
2209 /* Report the stop to the core. */
2213 if (event
== PTRACE_EVENT_FORK
)
2214 ourstatus
->kind
= TARGET_WAITKIND_FORKED
;
2215 else if (event
== PTRACE_EVENT_VFORK
)
2216 ourstatus
->kind
= TARGET_WAITKIND_VFORKED
;
2219 struct lwp_info
*new_lp
;
2221 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2223 new_lp
= add_lwp (BUILD_LWP (new_pid
, GET_PID (lp
->ptid
)));
2225 new_lp
->stopped
= 1;
2227 if (WSTOPSIG (status
) != SIGSTOP
)
2229 /* This can happen if someone starts sending signals to
2230 the new thread before it gets a chance to run, which
2231 have a lower number than SIGSTOP (e.g. SIGUSR1).
2232 This is an unlikely case, and harder to handle for
2233 fork / vfork than for clone, so we do not try - but
2234 we handle it for clone events here. We'll send
2235 the other signal on to the thread below. */
2237 new_lp
->signalled
= 1;
2241 struct thread_info
*tp
;
2243 /* When we stop for an event in some other thread, and
2244 pull the thread list just as this thread has cloned,
2245 we'll have seen the new thread in the thread_db list
2246 before handling the CLONE event (glibc's
2247 pthread_create adds the new thread to the thread list
2248 before clone'ing, and has the kernel fill in the
2249 thread's tid on the clone call with
2250 CLONE_PARENT_SETTID). If that happened, and the core
2251 had requested the new thread to stop, we'll have
2252 killed it with SIGSTOP. But since SIGSTOP is not an
2253 RT signal, it can only be queued once. We need to be
2254 careful to not resume the LWP if we wanted it to
2255 stop. In that case, we'll leave the SIGSTOP pending.
2256 It will later be reported as TARGET_SIGNAL_0. */
2257 tp
= find_thread_ptid (new_lp
->ptid
);
2258 if (tp
!= NULL
&& tp
->stop_requested
)
2259 new_lp
->last_resume_kind
= resume_stop
;
2266 /* Add the new thread to GDB's lists as soon as possible
2269 1) the frontend doesn't have to wait for a stop to
2272 2) we tag it with the correct running state. */
2274 /* If the thread_db layer is active, let it know about
2275 this new thread, and add it to GDB's list. */
2276 if (!thread_db_attach_lwp (new_lp
->ptid
))
2278 /* We're not using thread_db. Add it to GDB's
2280 target_post_attach (GET_LWP (new_lp
->ptid
));
2281 add_thread (new_lp
->ptid
);
2286 set_running (new_lp
->ptid
, 1);
2287 set_executing (new_lp
->ptid
, 1);
2293 /* We created NEW_LP so it cannot yet contain STATUS. */
2294 gdb_assert (new_lp
->status
== 0);
2296 /* Save the wait status to report later. */
2297 if (debug_linux_nat
)
2298 fprintf_unfiltered (gdb_stdlog
,
2299 "LHEW: waitpid of new LWP %ld, "
2300 "saving status %s\n",
2301 (long) GET_LWP (new_lp
->ptid
),
2302 status_to_str (status
));
2303 new_lp
->status
= status
;
2306 /* Note the need to use the low target ops to resume, to
2307 handle resuming with PT_SYSCALL if we have syscall
2311 new_lp
->resumed
= 1;
2315 if (debug_linux_nat
)
2316 fprintf_unfiltered (gdb_stdlog
,
2317 "LHEW: resuming new LWP %ld\n",
2318 GET_LWP (new_lp
->ptid
));
2319 linux_ops
->to_resume (linux_ops
, pid_to_ptid (new_pid
),
2320 0, TARGET_SIGNAL_0
);
2321 new_lp
->stopped
= 0;
2325 if (debug_linux_nat
)
2326 fprintf_unfiltered (gdb_stdlog
,
2327 "LHEW: Got clone event "
2328 "from LWP %ld, resuming\n",
2329 GET_LWP (lp
->ptid
));
2330 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
2331 0, TARGET_SIGNAL_0
);
2339 if (event
== PTRACE_EVENT_EXEC
)
2341 if (debug_linux_nat
)
2342 fprintf_unfiltered (gdb_stdlog
,
2343 "LHEW: Got exec event from LWP %ld\n",
2344 GET_LWP (lp
->ptid
));
2346 ourstatus
->kind
= TARGET_WAITKIND_EXECD
;
2347 ourstatus
->value
.execd_pathname
2348 = xstrdup (linux_child_pid_to_exec_file (pid
));
2353 if (event
== PTRACE_EVENT_VFORK_DONE
)
2355 if (current_inferior ()->waiting_for_vfork_done
)
2357 if (debug_linux_nat
)
2358 fprintf_unfiltered (gdb_stdlog
,
2359 "LHEW: Got expected PTRACE_EVENT_"
2360 "VFORK_DONE from LWP %ld: stopping\n",
2361 GET_LWP (lp
->ptid
));
2363 ourstatus
->kind
= TARGET_WAITKIND_VFORK_DONE
;
2367 if (debug_linux_nat
)
2368 fprintf_unfiltered (gdb_stdlog
,
2369 "LHEW: Got PTRACE_EVENT_VFORK_DONE "
2370 "from LWP %ld: resuming\n",
2371 GET_LWP (lp
->ptid
));
2372 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2376 internal_error (__FILE__
, __LINE__
,
2377 _("unknown ptrace event %d"), event
);
2380 /* Return non-zero if LWP is a zombie. */
2383 linux_lwp_is_zombie (long lwp
)
2385 char buffer
[MAXPATHLEN
];
2389 xsnprintf (buffer
, sizeof (buffer
), "/proc/%ld/status", lwp
);
2390 procfile
= fopen (buffer
, "r");
2391 if (procfile
== NULL
)
2393 warning (_("unable to open /proc file '%s'"), buffer
);
2396 while (fgets (buffer
, sizeof (buffer
), procfile
) != NULL
)
2397 if (strcmp (buffer
, "State:\tZ (zombie)\n") == 0)
2407 /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has
2411 wait_lwp (struct lwp_info
*lp
)
2415 int thread_dead
= 0;
2418 gdb_assert (!lp
->stopped
);
2419 gdb_assert (lp
->status
== 0);
2421 /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */
2422 block_child_signals (&prev_mask
);
2426 /* If my_waitpid returns 0 it means the __WCLONE vs. non-__WCLONE kind
2427 was right and we should just call sigsuspend. */
2429 pid
= my_waitpid (GET_LWP (lp
->ptid
), &status
, WNOHANG
);
2430 if (pid
== -1 && errno
== ECHILD
)
2431 pid
= my_waitpid (GET_LWP (lp
->ptid
), &status
, __WCLONE
| WNOHANG
);
2432 if (pid
== -1 && errno
== ECHILD
)
2434 /* The thread has previously exited. We need to delete it
2435 now because, for some vendor 2.4 kernels with NPTL
2436 support backported, there won't be an exit event unless
2437 it is the main thread. 2.6 kernels will report an exit
2438 event for each thread that exits, as expected. */
2440 if (debug_linux_nat
)
2441 fprintf_unfiltered (gdb_stdlog
, "WL: %s vanished.\n",
2442 target_pid_to_str (lp
->ptid
));
2447 /* Bugs 10970, 12702.
2448 Thread group leader may have exited in which case we'll lock up in
2449 waitpid if there are other threads, even if they are all zombies too.
2450 Basically, we're not supposed to use waitpid this way.
2451 __WCLONE is not applicable for the leader so we can't use that.
2452 LINUX_NAT_THREAD_ALIVE cannot be used here as it requires a STOPPED
2453 process; it gets ESRCH both for the zombie and for running processes.
2455 As a workaround, check if we're waiting for the thread group leader and
2456 if it's a zombie, and avoid calling waitpid if it is.
2458 This is racy, what if the tgl becomes a zombie right after we check?
2459 Therefore always use WNOHANG with sigsuspend - it is equivalent to
2460 waiting waitpid but the linux_lwp_is_zombie is safe this way. */
2462 if (GET_PID (lp
->ptid
) == GET_LWP (lp
->ptid
)
2463 && linux_lwp_is_zombie (GET_LWP (lp
->ptid
)))
2466 if (debug_linux_nat
)
2467 fprintf_unfiltered (gdb_stdlog
,
2468 "WL: Thread group leader %s vanished.\n",
2469 target_pid_to_str (lp
->ptid
));
2473 /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers
2474 get invoked despite our caller had them intentionally blocked by
2475 block_child_signals. This is sensitive only to the loop of
2476 linux_nat_wait_1 and there if we get called my_waitpid gets called
2477 again before it gets to sigsuspend so we can safely let the handlers
2478 get executed here. */
2480 sigsuspend (&suspend_mask
);
2483 restore_child_signals_mask (&prev_mask
);
2487 gdb_assert (pid
== GET_LWP (lp
->ptid
));
2489 if (debug_linux_nat
)
2491 fprintf_unfiltered (gdb_stdlog
,
2492 "WL: waitpid %s received %s\n",
2493 target_pid_to_str (lp
->ptid
),
2494 status_to_str (status
));
2497 /* Check if the thread has exited. */
2498 if (WIFEXITED (status
) || WIFSIGNALED (status
))
2501 if (debug_linux_nat
)
2502 fprintf_unfiltered (gdb_stdlog
, "WL: %s exited.\n",
2503 target_pid_to_str (lp
->ptid
));
2513 gdb_assert (WIFSTOPPED (status
));
2515 /* Handle GNU/Linux's syscall SIGTRAPs. */
2516 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SYSCALL_SIGTRAP
)
2518 /* No longer need the sysgood bit. The ptrace event ends up
2519 recorded in lp->waitstatus if we care for it. We can carry
2520 on handling the event like a regular SIGTRAP from here
2522 status
= W_STOPCODE (SIGTRAP
);
2523 if (linux_handle_syscall_trap (lp
, 1))
2524 return wait_lwp (lp
);
2527 /* Handle GNU/Linux's extended waitstatus for trace events. */
2528 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
2530 if (debug_linux_nat
)
2531 fprintf_unfiltered (gdb_stdlog
,
2532 "WL: Handling extended status 0x%06x\n",
2534 if (linux_handle_extended_wait (lp
, status
, 1))
2535 return wait_lwp (lp
);
2541 /* Save the most recent siginfo for LP. This is currently only called
2542 for SIGTRAP; some ports use the si_addr field for
2543 target_stopped_data_address. In the future, it may also be used to
2544 restore the siginfo of requeued signals. */
2547 save_siginfo (struct lwp_info
*lp
)
2550 ptrace (PTRACE_GETSIGINFO
, GET_LWP (lp
->ptid
),
2551 (PTRACE_TYPE_ARG3
) 0, &lp
->siginfo
);
2554 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
2557 /* Send a SIGSTOP to LP. */
2560 stop_callback (struct lwp_info
*lp
, void *data
)
2562 if (!lp
->stopped
&& !lp
->signalled
)
2566 if (debug_linux_nat
)
2568 fprintf_unfiltered (gdb_stdlog
,
2569 "SC: kill %s **<SIGSTOP>**\n",
2570 target_pid_to_str (lp
->ptid
));
2573 ret
= kill_lwp (GET_LWP (lp
->ptid
), SIGSTOP
);
2574 if (debug_linux_nat
)
2576 fprintf_unfiltered (gdb_stdlog
,
2577 "SC: lwp kill %d %s\n",
2579 errno
? safe_strerror (errno
) : "ERRNO-OK");
2583 gdb_assert (lp
->status
== 0);
2589 /* Return non-zero if LWP PID has a pending SIGINT. */
2592 linux_nat_has_pending_sigint (int pid
)
2594 sigset_t pending
, blocked
, ignored
;
2596 linux_proc_pending_signals (pid
, &pending
, &blocked
, &ignored
);
2598 if (sigismember (&pending
, SIGINT
)
2599 && !sigismember (&ignored
, SIGINT
))
2605 /* Set a flag in LP indicating that we should ignore its next SIGINT. */
2608 set_ignore_sigint (struct lwp_info
*lp
, void *data
)
2610 /* If a thread has a pending SIGINT, consume it; otherwise, set a
2611 flag to consume the next one. */
2612 if (lp
->stopped
&& lp
->status
!= 0 && WIFSTOPPED (lp
->status
)
2613 && WSTOPSIG (lp
->status
) == SIGINT
)
2616 lp
->ignore_sigint
= 1;
2621 /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag.
2622 This function is called after we know the LWP has stopped; if the LWP
2623 stopped before the expected SIGINT was delivered, then it will never have
2624 arrived. Also, if the signal was delivered to a shared queue and consumed
2625 by a different thread, it will never be delivered to this LWP. */
2628 maybe_clear_ignore_sigint (struct lwp_info
*lp
)
2630 if (!lp
->ignore_sigint
)
2633 if (!linux_nat_has_pending_sigint (GET_LWP (lp
->ptid
)))
2635 if (debug_linux_nat
)
2636 fprintf_unfiltered (gdb_stdlog
,
2637 "MCIS: Clearing bogus flag for %s\n",
2638 target_pid_to_str (lp
->ptid
));
2639 lp
->ignore_sigint
= 0;
2643 /* Fetch the possible triggered data watchpoint info and store it in
2646 On some archs, like x86, that use debug registers to set
2647 watchpoints, it's possible that the way to know which watched
2648 address trapped, is to check the register that is used to select
2649 which address to watch. Problem is, between setting the watchpoint
2650 and reading back which data address trapped, the user may change
2651 the set of watchpoints, and, as a consequence, GDB changes the
2652 debug registers in the inferior. To avoid reading back a stale
2653 stopped-data-address when that happens, we cache in LP the fact
2654 that a watchpoint trapped, and the corresponding data address, as
2655 soon as we see LP stop with a SIGTRAP. If GDB changes the debug
2656 registers meanwhile, we have the cached data we can rely on. */
2659 save_sigtrap (struct lwp_info
*lp
)
2661 struct cleanup
*old_chain
;
2663 if (linux_ops
->to_stopped_by_watchpoint
== NULL
)
2665 lp
->stopped_by_watchpoint
= 0;
2669 old_chain
= save_inferior_ptid ();
2670 inferior_ptid
= lp
->ptid
;
2672 lp
->stopped_by_watchpoint
= linux_ops
->to_stopped_by_watchpoint ();
2674 if (lp
->stopped_by_watchpoint
)
2676 if (linux_ops
->to_stopped_data_address
!= NULL
)
2677 lp
->stopped_data_address_p
=
2678 linux_ops
->to_stopped_data_address (¤t_target
,
2679 &lp
->stopped_data_address
);
2681 lp
->stopped_data_address_p
= 0;
2684 do_cleanups (old_chain
);
2687 /* See save_sigtrap. */
2690 linux_nat_stopped_by_watchpoint (void)
2692 struct lwp_info
*lp
= find_lwp_pid (inferior_ptid
);
2694 gdb_assert (lp
!= NULL
);
2696 return lp
->stopped_by_watchpoint
;
2700 linux_nat_stopped_data_address (struct target_ops
*ops
, CORE_ADDR
*addr_p
)
2702 struct lwp_info
*lp
= find_lwp_pid (inferior_ptid
);
2704 gdb_assert (lp
!= NULL
);
2706 *addr_p
= lp
->stopped_data_address
;
2708 return lp
->stopped_data_address_p
;
2711 /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */
2714 sigtrap_is_event (int status
)
2716 return WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
;
2719 /* SIGTRAP-like events recognizer. */
2721 static int (*linux_nat_status_is_event
) (int status
) = sigtrap_is_event
;
2723 /* Check for SIGTRAP-like events in LP. */
2726 linux_nat_lp_status_is_event (struct lwp_info
*lp
)
2728 /* We check for lp->waitstatus in addition to lp->status, because we can
2729 have pending process exits recorded in lp->status
2730 and W_EXITCODE(0,0) == 0. We should probably have an additional
2731 lp->status_p flag. */
2733 return (lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
2734 && linux_nat_status_is_event (lp
->status
));
2737 /* Set alternative SIGTRAP-like events recognizer. If
2738 breakpoint_inserted_here_p there then gdbarch_decr_pc_after_break will be
2742 linux_nat_set_status_is_event (struct target_ops
*t
,
2743 int (*status_is_event
) (int status
))
2745 linux_nat_status_is_event
= status_is_event
;
2748 /* Wait until LP is stopped. */
2751 stop_wait_callback (struct lwp_info
*lp
, void *data
)
2753 struct inferior
*inf
= find_inferior_pid (GET_PID (lp
->ptid
));
2755 /* If this is a vfork parent, bail out, it is not going to report
2756 any SIGSTOP until the vfork is done with. */
2757 if (inf
->vfork_child
!= NULL
)
2764 status
= wait_lwp (lp
);
2768 if (lp
->ignore_sigint
&& WIFSTOPPED (status
)
2769 && WSTOPSIG (status
) == SIGINT
)
2771 lp
->ignore_sigint
= 0;
2774 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2775 if (debug_linux_nat
)
2776 fprintf_unfiltered (gdb_stdlog
,
2777 "PTRACE_CONT %s, 0, 0 (%s) "
2778 "(discarding SIGINT)\n",
2779 target_pid_to_str (lp
->ptid
),
2780 errno
? safe_strerror (errno
) : "OK");
2782 return stop_wait_callback (lp
, NULL
);
2785 maybe_clear_ignore_sigint (lp
);
2787 if (WSTOPSIG (status
) != SIGSTOP
)
2789 if (linux_nat_status_is_event (status
))
2791 /* If a LWP other than the LWP that we're reporting an
2792 event for has hit a GDB breakpoint (as opposed to
2793 some random trap signal), then just arrange for it to
2794 hit it again later. We don't keep the SIGTRAP status
2795 and don't forward the SIGTRAP signal to the LWP. We
2796 will handle the current event, eventually we will
2797 resume all LWPs, and this one will get its breakpoint
2800 If we do not do this, then we run the risk that the
2801 user will delete or disable the breakpoint, but the
2802 thread will have already tripped on it. */
2804 /* Save the trap's siginfo in case we need it later. */
2809 /* Now resume this LWP and get the SIGSTOP event. */
2811 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2812 if (debug_linux_nat
)
2814 fprintf_unfiltered (gdb_stdlog
,
2815 "PTRACE_CONT %s, 0, 0 (%s)\n",
2816 target_pid_to_str (lp
->ptid
),
2817 errno
? safe_strerror (errno
) : "OK");
2819 fprintf_unfiltered (gdb_stdlog
,
2820 "SWC: Candidate SIGTRAP event in %s\n",
2821 target_pid_to_str (lp
->ptid
));
2823 /* Hold this event/waitstatus while we check to see if
2824 there are any more (we still want to get that SIGSTOP). */
2825 stop_wait_callback (lp
, NULL
);
2827 /* Hold the SIGTRAP for handling by linux_nat_wait. If
2828 there's another event, throw it back into the
2832 if (debug_linux_nat
)
2833 fprintf_unfiltered (gdb_stdlog
,
2834 "SWC: kill %s, %s\n",
2835 target_pid_to_str (lp
->ptid
),
2836 status_to_str ((int) status
));
2837 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (lp
->status
));
2840 /* Save the sigtrap event. */
2841 lp
->status
= status
;
2846 /* The thread was stopped with a signal other than
2847 SIGSTOP, and didn't accidentally trip a breakpoint. */
2849 if (debug_linux_nat
)
2851 fprintf_unfiltered (gdb_stdlog
,
2852 "SWC: Pending event %s in %s\n",
2853 status_to_str ((int) status
),
2854 target_pid_to_str (lp
->ptid
));
2856 /* Now resume this LWP and get the SIGSTOP event. */
2858 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2859 if (debug_linux_nat
)
2860 fprintf_unfiltered (gdb_stdlog
,
2861 "SWC: PTRACE_CONT %s, 0, 0 (%s)\n",
2862 target_pid_to_str (lp
->ptid
),
2863 errno
? safe_strerror (errno
) : "OK");
2865 /* Hold this event/waitstatus while we check to see if
2866 there are any more (we still want to get that SIGSTOP). */
2867 stop_wait_callback (lp
, NULL
);
2869 /* If the lp->status field is still empty, use it to
2870 hold this event. If not, then this event must be
2871 returned to the event queue of the LWP. */
2874 if (debug_linux_nat
)
2876 fprintf_unfiltered (gdb_stdlog
,
2877 "SWC: kill %s, %s\n",
2878 target_pid_to_str (lp
->ptid
),
2879 status_to_str ((int) status
));
2881 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (status
));
2884 lp
->status
= status
;
2890 /* We caught the SIGSTOP that we intended to catch, so
2891 there's no SIGSTOP pending. */
2900 /* Return non-zero if LP has a wait status pending. */
2903 status_callback (struct lwp_info
*lp
, void *data
)
2905 /* Only report a pending wait status if we pretend that this has
2906 indeed been resumed. */
2910 if (lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
2912 /* A ptrace event, like PTRACE_FORK|VFORK|EXEC, syscall event,
2913 or a pending process exit. Note that `W_EXITCODE(0,0) ==
2914 0', so a clean process exit can not be stored pending in
2915 lp->status, it is indistinguishable from
2916 no-pending-status. */
2920 if (lp
->status
!= 0)
2926 /* Return non-zero if LP isn't stopped. */
2929 running_callback (struct lwp_info
*lp
, void *data
)
2931 return (!lp
->stopped
2932 || ((lp
->status
!= 0
2933 || lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
2937 /* Count the LWP's that have had events. */
2940 count_events_callback (struct lwp_info
*lp
, void *data
)
2944 gdb_assert (count
!= NULL
);
2946 /* Count only resumed LWPs that have a SIGTRAP event pending. */
2947 if (lp
->resumed
&& linux_nat_lp_status_is_event (lp
))
2953 /* Select the LWP (if any) that is currently being single-stepped. */
2956 select_singlestep_lwp_callback (struct lwp_info
*lp
, void *data
)
2958 if (lp
->last_resume_kind
== resume_step
2965 /* Select the Nth LWP that has had a SIGTRAP event. */
2968 select_event_lwp_callback (struct lwp_info
*lp
, void *data
)
2970 int *selector
= data
;
2972 gdb_assert (selector
!= NULL
);
2974 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2975 if (lp
->resumed
&& linux_nat_lp_status_is_event (lp
))
2976 if ((*selector
)-- == 0)
2983 cancel_breakpoint (struct lwp_info
*lp
)
2985 /* Arrange for a breakpoint to be hit again later. We don't keep
2986 the SIGTRAP status and don't forward the SIGTRAP signal to the
2987 LWP. We will handle the current event, eventually we will resume
2988 this LWP, and this breakpoint will trap again.
2990 If we do not do this, then we run the risk that the user will
2991 delete or disable the breakpoint, but the LWP will have already
2994 struct regcache
*regcache
= get_thread_regcache (lp
->ptid
);
2995 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2998 pc
= regcache_read_pc (regcache
) - gdbarch_decr_pc_after_break (gdbarch
);
2999 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3001 if (debug_linux_nat
)
3002 fprintf_unfiltered (gdb_stdlog
,
3003 "CB: Push back breakpoint for %s\n",
3004 target_pid_to_str (lp
->ptid
));
3006 /* Back up the PC if necessary. */
3007 if (gdbarch_decr_pc_after_break (gdbarch
))
3008 regcache_write_pc (regcache
, pc
);
3016 cancel_breakpoints_callback (struct lwp_info
*lp
, void *data
)
3018 struct lwp_info
*event_lp
= data
;
3020 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
3024 /* If a LWP other than the LWP that we're reporting an event for has
3025 hit a GDB breakpoint (as opposed to some random trap signal),
3026 then just arrange for it to hit it again later. We don't keep
3027 the SIGTRAP status and don't forward the SIGTRAP signal to the
3028 LWP. We will handle the current event, eventually we will resume
3029 all LWPs, and this one will get its breakpoint trap again.
3031 If we do not do this, then we run the risk that the user will
3032 delete or disable the breakpoint, but the LWP will have already
3035 if (linux_nat_lp_status_is_event (lp
)
3036 && cancel_breakpoint (lp
))
3037 /* Throw away the SIGTRAP. */
3043 /* Select one LWP out of those that have events pending. */
3046 select_event_lwp (ptid_t filter
, struct lwp_info
**orig_lp
, int *status
)
3049 int random_selector
;
3050 struct lwp_info
*event_lp
;
3052 /* Record the wait status for the original LWP. */
3053 (*orig_lp
)->status
= *status
;
3055 /* Give preference to any LWP that is being single-stepped. */
3056 event_lp
= iterate_over_lwps (filter
,
3057 select_singlestep_lwp_callback
, NULL
);
3058 if (event_lp
!= NULL
)
3060 if (debug_linux_nat
)
3061 fprintf_unfiltered (gdb_stdlog
,
3062 "SEL: Select single-step %s\n",
3063 target_pid_to_str (event_lp
->ptid
));
3067 /* No single-stepping LWP. Select one at random, out of those
3068 which have had SIGTRAP events. */
3070 /* First see how many SIGTRAP events we have. */
3071 iterate_over_lwps (filter
, count_events_callback
, &num_events
);
3073 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
3074 random_selector
= (int)
3075 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3077 if (debug_linux_nat
&& num_events
> 1)
3078 fprintf_unfiltered (gdb_stdlog
,
3079 "SEL: Found %d SIGTRAP events, selecting #%d\n",
3080 num_events
, random_selector
);
3082 event_lp
= iterate_over_lwps (filter
,
3083 select_event_lwp_callback
,
3087 if (event_lp
!= NULL
)
3089 /* Switch the event LWP. */
3090 *orig_lp
= event_lp
;
3091 *status
= event_lp
->status
;
3094 /* Flush the wait status for the event LWP. */
3095 (*orig_lp
)->status
= 0;
3098 /* Return non-zero if LP has been resumed. */
3101 resumed_callback (struct lwp_info
*lp
, void *data
)
3106 /* Stop an active thread, verify it still exists, then resume it. */
3109 stop_and_resume_callback (struct lwp_info
*lp
, void *data
)
3113 enum resume_kind last_resume_kind
= lp
->last_resume_kind
;
3114 ptid_t ptid
= lp
->ptid
;
3116 stop_callback (lp
, NULL
);
3117 stop_wait_callback (lp
, NULL
);
3119 /* Resume if the lwp still exists, and the core wanted it
3121 if (last_resume_kind
!= resume_stop
)
3123 lp
= find_lwp_pid (ptid
);
3125 resume_lwp (lp
, lp
->step
);
3131 /* Check if we should go on and pass this event to common code.
3132 Return the affected lwp if we are, or NULL otherwise. */
3133 static struct lwp_info
*
3134 linux_nat_filter_event (int lwpid
, int status
, int options
)
3136 struct lwp_info
*lp
;
3138 lp
= find_lwp_pid (pid_to_ptid (lwpid
));
3140 /* Check for stop events reported by a process we didn't already
3141 know about - anything not already in our LWP list.
3143 If we're expecting to receive stopped processes after
3144 fork, vfork, and clone events, then we'll just add the
3145 new one to our list and go back to waiting for the event
3146 to be reported - the stopped process might be returned
3147 from waitpid before or after the event is. */
3148 if (WIFSTOPPED (status
) && !lp
)
3150 add_to_pid_list (&stopped_pids
, lwpid
, status
);
3154 /* Make sure we don't report an event for the exit of an LWP not in
3155 our list, i.e. not part of the current process. This can happen
3156 if we detach from a program we originally forked and then it
3158 if (!WIFSTOPPED (status
) && !lp
)
3161 /* NOTE drow/2003-06-17: This code seems to be meant for debugging
3162 CLONE_PTRACE processes which do not use the thread library -
3163 otherwise we wouldn't find the new LWP this way. That doesn't
3164 currently work, and the following code is currently unreachable
3165 due to the two blocks above. If it's fixed some day, this code
3166 should be broken out into a function so that we can also pick up
3167 LWPs from the new interface. */
3170 lp
= add_lwp (BUILD_LWP (lwpid
, GET_PID (inferior_ptid
)));
3171 if (options
& __WCLONE
)
3174 gdb_assert (WIFSTOPPED (status
)
3175 && WSTOPSIG (status
) == SIGSTOP
);
3178 if (!in_thread_list (inferior_ptid
))
3180 inferior_ptid
= BUILD_LWP (GET_PID (inferior_ptid
),
3181 GET_PID (inferior_ptid
));
3182 add_thread (inferior_ptid
);
3185 add_thread (lp
->ptid
);
3188 /* Handle GNU/Linux's syscall SIGTRAPs. */
3189 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SYSCALL_SIGTRAP
)
3191 /* No longer need the sysgood bit. The ptrace event ends up
3192 recorded in lp->waitstatus if we care for it. We can carry
3193 on handling the event like a regular SIGTRAP from here
3195 status
= W_STOPCODE (SIGTRAP
);
3196 if (linux_handle_syscall_trap (lp
, 0))
3200 /* Handle GNU/Linux's extended waitstatus for trace events. */
3201 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
3203 if (debug_linux_nat
)
3204 fprintf_unfiltered (gdb_stdlog
,
3205 "LLW: Handling extended status 0x%06x\n",
3207 if (linux_handle_extended_wait (lp
, status
, 0))
3211 if (linux_nat_status_is_event (status
))
3213 /* Save the trap's siginfo in case we need it later. */
3219 /* Check if the thread has exited. */
3220 if ((WIFEXITED (status
) || WIFSIGNALED (status
))
3221 && num_lwps (GET_PID (lp
->ptid
)) > 1)
3223 /* If this is the main thread, we must stop all threads and verify
3224 if they are still alive. This is because in the nptl thread model
3225 on Linux 2.4, there is no signal issued for exiting LWPs
3226 other than the main thread. We only get the main thread exit
3227 signal once all child threads have already exited. If we
3228 stop all the threads and use the stop_wait_callback to check
3229 if they have exited we can determine whether this signal
3230 should be ignored or whether it means the end of the debugged
3231 application, regardless of which threading model is being
3233 if (GET_PID (lp
->ptid
) == GET_LWP (lp
->ptid
))
3236 iterate_over_lwps (pid_to_ptid (GET_PID (lp
->ptid
)),
3237 stop_and_resume_callback
, NULL
);
3240 if (debug_linux_nat
)
3241 fprintf_unfiltered (gdb_stdlog
,
3242 "LLW: %s exited.\n",
3243 target_pid_to_str (lp
->ptid
));
3245 if (num_lwps (GET_PID (lp
->ptid
)) > 1)
3247 /* If there is at least one more LWP, then the exit signal
3248 was not the end of the debugged application and should be
3255 /* Check if the current LWP has previously exited. In the nptl
3256 thread model, LWPs other than the main thread do not issue
3257 signals when they exit so we must check whenever the thread has
3258 stopped. A similar check is made in stop_wait_callback(). */
3259 if (num_lwps (GET_PID (lp
->ptid
)) > 1 && !linux_thread_alive (lp
->ptid
))
3261 ptid_t ptid
= pid_to_ptid (GET_PID (lp
->ptid
));
3263 if (debug_linux_nat
)
3264 fprintf_unfiltered (gdb_stdlog
,
3265 "LLW: %s exited.\n",
3266 target_pid_to_str (lp
->ptid
));
3270 /* Make sure there is at least one thread running. */
3271 gdb_assert (iterate_over_lwps (ptid
, running_callback
, NULL
));
3273 /* Discard the event. */
3277 /* Make sure we don't report a SIGSTOP that we sent ourselves in
3278 an attempt to stop an LWP. */
3280 && WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGSTOP
)
3282 if (debug_linux_nat
)
3283 fprintf_unfiltered (gdb_stdlog
,
3284 "LLW: Delayed SIGSTOP caught for %s.\n",
3285 target_pid_to_str (lp
->ptid
));
3289 if (lp
->last_resume_kind
!= resume_stop
)
3291 /* This is a delayed SIGSTOP. */
3293 registers_changed ();
3295 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3296 lp
->step
, TARGET_SIGNAL_0
);
3297 if (debug_linux_nat
)
3298 fprintf_unfiltered (gdb_stdlog
,
3299 "LLW: %s %s, 0, 0 (discard SIGSTOP)\n",
3301 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3302 target_pid_to_str (lp
->ptid
));
3305 gdb_assert (lp
->resumed
);
3307 /* Discard the event. */
3312 /* Make sure we don't report a SIGINT that we have already displayed
3313 for another thread. */
3314 if (lp
->ignore_sigint
3315 && WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGINT
)
3317 if (debug_linux_nat
)
3318 fprintf_unfiltered (gdb_stdlog
,
3319 "LLW: Delayed SIGINT caught for %s.\n",
3320 target_pid_to_str (lp
->ptid
));
3322 /* This is a delayed SIGINT. */
3323 lp
->ignore_sigint
= 0;
3325 registers_changed ();
3326 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3327 lp
->step
, TARGET_SIGNAL_0
);
3328 if (debug_linux_nat
)
3329 fprintf_unfiltered (gdb_stdlog
,
3330 "LLW: %s %s, 0, 0 (discard SIGINT)\n",
3332 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3333 target_pid_to_str (lp
->ptid
));
3336 gdb_assert (lp
->resumed
);
3338 /* Discard the event. */
3342 /* An interesting event. */
3344 lp
->status
= status
;
3349 linux_nat_wait_1 (struct target_ops
*ops
,
3350 ptid_t ptid
, struct target_waitstatus
*ourstatus
,
3353 static sigset_t prev_mask
;
3354 enum resume_kind last_resume_kind
;
3355 struct lwp_info
*lp
= NULL
;
3360 if (debug_linux_nat
)
3361 fprintf_unfiltered (gdb_stdlog
, "LLW: enter\n");
3363 /* The first time we get here after starting a new inferior, we may
3364 not have added it to the LWP list yet - this is the earliest
3365 moment at which we know its PID. */
3366 if (ptid_is_pid (inferior_ptid
))
3368 /* Upgrade the main thread's ptid. */
3369 thread_change_ptid (inferior_ptid
,
3370 BUILD_LWP (GET_PID (inferior_ptid
),
3371 GET_PID (inferior_ptid
)));
3373 lp
= add_lwp (inferior_ptid
);
3377 /* Make sure SIGCHLD is blocked. */
3378 block_child_signals (&prev_mask
);
3380 if (ptid_equal (ptid
, minus_one_ptid
))
3382 else if (ptid_is_pid (ptid
))
3383 /* A request to wait for a specific tgid. This is not possible
3384 with waitpid, so instead, we wait for any child, and leave
3385 children we're not interested in right now with a pending
3386 status to report later. */
3389 pid
= GET_LWP (ptid
);
3395 /* Make sure that of those LWPs we want to get an event from, there
3396 is at least one LWP that has been resumed. If there's none, just
3397 bail out. The core may just be flushing asynchronously all
3399 if (iterate_over_lwps (ptid
, resumed_callback
, NULL
) == NULL
)
3401 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3403 if (debug_linux_nat
)
3404 fprintf_unfiltered (gdb_stdlog
, "LLW: exit (no resumed LWP)\n");
3406 restore_child_signals_mask (&prev_mask
);
3407 return minus_one_ptid
;
3410 /* First check if there is a LWP with a wait status pending. */
3413 /* Any LWP that's been resumed will do. */
3414 lp
= iterate_over_lwps (ptid
, status_callback
, NULL
);
3417 if (debug_linux_nat
&& lp
->status
)
3418 fprintf_unfiltered (gdb_stdlog
,
3419 "LLW: Using pending wait status %s for %s.\n",
3420 status_to_str (lp
->status
),
3421 target_pid_to_str (lp
->ptid
));
3424 /* But if we don't find one, we'll have to wait, and check both
3425 cloned and uncloned processes. We start with the cloned
3427 options
= __WCLONE
| WNOHANG
;
3429 else if (is_lwp (ptid
))
3431 if (debug_linux_nat
)
3432 fprintf_unfiltered (gdb_stdlog
,
3433 "LLW: Waiting for specific LWP %s.\n",
3434 target_pid_to_str (ptid
));
3436 /* We have a specific LWP to check. */
3437 lp
= find_lwp_pid (ptid
);
3440 if (debug_linux_nat
&& lp
->status
)
3441 fprintf_unfiltered (gdb_stdlog
,
3442 "LLW: Using pending wait status %s for %s.\n",
3443 status_to_str (lp
->status
),
3444 target_pid_to_str (lp
->ptid
));
3446 /* If we have to wait, take into account whether PID is a cloned
3447 process or not. And we have to convert it to something that
3448 the layer beneath us can understand. */
3449 options
= lp
->cloned
? __WCLONE
: 0;
3450 pid
= GET_LWP (ptid
);
3452 /* We check for lp->waitstatus in addition to lp->status,
3453 because we can have pending process exits recorded in
3454 lp->status and W_EXITCODE(0,0) == 0. We should probably have
3455 an additional lp->status_p flag. */
3456 if (lp
->status
== 0 && lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
)
3460 if (lp
&& lp
->signalled
&& lp
->last_resume_kind
!= resume_stop
)
3462 /* A pending SIGSTOP may interfere with the normal stream of
3463 events. In a typical case where interference is a problem,
3464 we have a SIGSTOP signal pending for LWP A while
3465 single-stepping it, encounter an event in LWP B, and take the
3466 pending SIGSTOP while trying to stop LWP A. After processing
3467 the event in LWP B, LWP A is continued, and we'll never see
3468 the SIGTRAP associated with the last time we were
3469 single-stepping LWP A. */
3471 /* Resume the thread. It should halt immediately returning the
3473 registers_changed ();
3474 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3475 lp
->step
, TARGET_SIGNAL_0
);
3476 if (debug_linux_nat
)
3477 fprintf_unfiltered (gdb_stdlog
,
3478 "LLW: %s %s, 0, 0 (expect SIGSTOP)\n",
3479 lp
->step
? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3480 target_pid_to_str (lp
->ptid
));
3482 gdb_assert (lp
->resumed
);
3484 /* Catch the pending SIGSTOP. */
3485 status
= lp
->status
;
3488 stop_wait_callback (lp
, NULL
);
3490 /* If the lp->status field isn't empty, we caught another signal
3491 while flushing the SIGSTOP. Return it back to the event
3492 queue of the LWP, as we already have an event to handle. */
3495 if (debug_linux_nat
)
3496 fprintf_unfiltered (gdb_stdlog
,
3497 "LLW: kill %s, %s\n",
3498 target_pid_to_str (lp
->ptid
),
3499 status_to_str (lp
->status
));
3500 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (lp
->status
));
3503 lp
->status
= status
;
3506 if (!target_can_async_p ())
3508 /* Causes SIGINT to be passed on to the attached process. */
3512 /* Translate generic target_wait options into waitpid options. */
3513 if (target_options
& TARGET_WNOHANG
)
3520 lwpid
= my_waitpid (pid
, &status
, options
);
3524 gdb_assert (pid
== -1 || lwpid
== pid
);
3526 if (debug_linux_nat
)
3528 fprintf_unfiltered (gdb_stdlog
,
3529 "LLW: waitpid %ld received %s\n",
3530 (long) lwpid
, status_to_str (status
));
3533 lp
= linux_nat_filter_event (lwpid
, status
, options
);
3535 /* STATUS is now no longer valid, use LP->STATUS instead. */
3539 && ptid_is_pid (ptid
)
3540 && ptid_get_pid (lp
->ptid
) != ptid_get_pid (ptid
))
3542 gdb_assert (lp
->resumed
);
3544 if (debug_linux_nat
)
3546 "LWP %ld got an event %06x, leaving pending.\n",
3547 ptid_get_lwp (lp
->ptid
), lp
->status
);
3549 if (WIFSTOPPED (lp
->status
))
3551 if (WSTOPSIG (lp
->status
) != SIGSTOP
)
3553 /* Cancel breakpoint hits. The breakpoint may
3554 be removed before we fetch events from this
3555 process to report to the core. It is best
3556 not to assume the moribund breakpoints
3557 heuristic always handles these cases --- it
3558 could be too many events go through to the
3559 core before this one is handled. All-stop
3560 always cancels breakpoint hits in all
3563 && linux_nat_lp_status_is_event (lp
)
3564 && cancel_breakpoint (lp
))
3566 /* Throw away the SIGTRAP. */
3569 if (debug_linux_nat
)
3571 "LLW: LWP %ld hit a breakpoint while"
3572 " waiting for another process;"
3574 ptid_get_lwp (lp
->ptid
));
3584 else if (WIFEXITED (lp
->status
) || WIFSIGNALED (lp
->status
))
3586 if (debug_linux_nat
)
3588 "Process %ld exited while stopping LWPs\n",
3589 ptid_get_lwp (lp
->ptid
));
3591 /* This was the last lwp in the process. Since
3592 events are serialized to GDB core, and we can't
3593 report this one right now, but GDB core and the
3594 other target layers will want to be notified
3595 about the exit code/signal, leave the status
3596 pending for the next time we're able to report
3599 /* Prevent trying to stop this thread again. We'll
3600 never try to resume it because it has a pending
3604 /* Dead LWP's aren't expected to reported a pending
3608 /* Store the pending event in the waitstatus as
3609 well, because W_EXITCODE(0,0) == 0. */
3610 store_waitstatus (&lp
->waitstatus
, lp
->status
);
3624 /* waitpid did return something. Restart over. */
3625 options
|= __WCLONE
;
3633 /* Alternate between checking cloned and uncloned processes. */
3634 options
^= __WCLONE
;
3636 /* And every time we have checked both:
3637 In async mode, return to event loop;
3638 In sync mode, suspend waiting for a SIGCHLD signal. */
3639 if (options
& __WCLONE
)
3641 if (target_options
& TARGET_WNOHANG
)
3643 /* No interesting event. */
3644 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3646 if (debug_linux_nat
)
3647 fprintf_unfiltered (gdb_stdlog
, "LLW: exit (ignore)\n");
3649 restore_child_signals_mask (&prev_mask
);
3650 return minus_one_ptid
;
3653 sigsuspend (&suspend_mask
);
3656 else if (target_options
& TARGET_WNOHANG
)
3658 /* No interesting event for PID yet. */
3659 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3661 if (debug_linux_nat
)
3662 fprintf_unfiltered (gdb_stdlog
, "LLW: exit (ignore)\n");
3664 restore_child_signals_mask (&prev_mask
);
3665 return minus_one_ptid
;
3668 /* We shouldn't end up here unless we want to try again. */
3669 gdb_assert (lp
== NULL
);
3672 if (!target_can_async_p ())
3673 clear_sigint_trap ();
3677 status
= lp
->status
;
3680 /* Don't report signals that GDB isn't interested in, such as
3681 signals that are neither printed nor stopped upon. Stopping all
3682 threads can be a bit time-consuming so if we want decent
3683 performance with heavily multi-threaded programs, especially when
3684 they're using a high frequency timer, we'd better avoid it if we
3687 if (WIFSTOPPED (status
))
3689 enum target_signal signo
= target_signal_from_host (WSTOPSIG (status
));
3691 /* When using hardware single-step, we need to report every signal.
3692 Otherwise, signals in pass_mask may be short-circuited. */
3694 && WSTOPSIG (status
) && sigismember (&pass_mask
, WSTOPSIG (status
)))
3696 /* FIMXE: kettenis/2001-06-06: Should we resume all threads
3697 here? It is not clear we should. GDB may not expect
3698 other threads to run. On the other hand, not resuming
3699 newly attached threads may cause an unwanted delay in
3700 getting them running. */
3701 registers_changed ();
3702 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3704 if (debug_linux_nat
)
3705 fprintf_unfiltered (gdb_stdlog
,
3706 "LLW: %s %s, %s (preempt 'handle')\n",
3708 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3709 target_pid_to_str (lp
->ptid
),
3710 (signo
!= TARGET_SIGNAL_0
3711 ? strsignal (target_signal_to_host (signo
))
3719 /* Only do the below in all-stop, as we currently use SIGINT
3720 to implement target_stop (see linux_nat_stop) in
3722 if (signo
== TARGET_SIGNAL_INT
&& signal_pass_state (signo
) == 0)
3724 /* If ^C/BREAK is typed at the tty/console, SIGINT gets
3725 forwarded to the entire process group, that is, all LWPs
3726 will receive it - unless they're using CLONE_THREAD to
3727 share signals. Since we only want to report it once, we
3728 mark it as ignored for all LWPs except this one. */
3729 iterate_over_lwps (pid_to_ptid (ptid_get_pid (ptid
)),
3730 set_ignore_sigint
, NULL
);
3731 lp
->ignore_sigint
= 0;
3734 maybe_clear_ignore_sigint (lp
);
3738 /* This LWP is stopped now. */
3741 if (debug_linux_nat
)
3742 fprintf_unfiltered (gdb_stdlog
, "LLW: Candidate event %s in %s.\n",
3743 status_to_str (status
), target_pid_to_str (lp
->ptid
));
3747 /* Now stop all other LWP's ... */
3748 iterate_over_lwps (minus_one_ptid
, stop_callback
, NULL
);
3750 /* ... and wait until all of them have reported back that
3751 they're no longer running. */
3752 iterate_over_lwps (minus_one_ptid
, stop_wait_callback
, NULL
);
3754 /* If we're not waiting for a specific LWP, choose an event LWP
3755 from among those that have had events. Giving equal priority
3756 to all LWPs that have had events helps prevent
3759 select_event_lwp (ptid
, &lp
, &status
);
3761 /* Now that we've selected our final event LWP, cancel any
3762 breakpoints in other LWPs that have hit a GDB breakpoint.
3763 See the comment in cancel_breakpoints_callback to find out
3765 iterate_over_lwps (minus_one_ptid
, cancel_breakpoints_callback
, lp
);
3767 /* We'll need this to determine whether to report a SIGSTOP as
3768 TARGET_WAITKIND_0. Need to take a copy because
3769 resume_clear_callback clears it. */
3770 last_resume_kind
= lp
->last_resume_kind
;
3772 /* In all-stop, from the core's perspective, all LWPs are now
3773 stopped until a new resume action is sent over. */
3774 iterate_over_lwps (minus_one_ptid
, resume_clear_callback
, NULL
);
3779 last_resume_kind
= lp
->last_resume_kind
;
3780 resume_clear_callback (lp
, NULL
);
3783 if (linux_nat_status_is_event (status
))
3785 if (debug_linux_nat
)
3786 fprintf_unfiltered (gdb_stdlog
,
3787 "LLW: trap ptid is %s.\n",
3788 target_pid_to_str (lp
->ptid
));
3791 if (lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3793 *ourstatus
= lp
->waitstatus
;
3794 lp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3797 store_waitstatus (ourstatus
, status
);
3799 if (debug_linux_nat
)
3800 fprintf_unfiltered (gdb_stdlog
, "LLW: exit\n");
3802 restore_child_signals_mask (&prev_mask
);
3804 if (last_resume_kind
== resume_stop
3805 && ourstatus
->kind
== TARGET_WAITKIND_STOPPED
3806 && WSTOPSIG (status
) == SIGSTOP
)
3808 /* A thread that has been requested to stop by GDB with
3809 target_stop, and it stopped cleanly, so report as SIG0. The
3810 use of SIGSTOP is an implementation detail. */
3811 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
3814 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
3815 || ourstatus
->kind
== TARGET_WAITKIND_SIGNALLED
)
3818 lp
->core
= linux_nat_core_of_thread_1 (lp
->ptid
);
3823 /* Resume LWPs that are currently stopped without any pending status
3824 to report, but are resumed from the core's perspective. */
3827 resume_stopped_resumed_lwps (struct lwp_info
*lp
, void *data
)
3829 ptid_t
*wait_ptid_p
= data
;
3834 && lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
)
3836 gdb_assert (is_executing (lp
->ptid
));
3838 /* Don't bother if there's a breakpoint at PC that we'd hit
3839 immediately, and we're not waiting for this LWP. */
3840 if (!ptid_match (lp
->ptid
, *wait_ptid_p
))
3842 struct regcache
*regcache
= get_thread_regcache (lp
->ptid
);
3843 CORE_ADDR pc
= regcache_read_pc (regcache
);
3845 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3849 if (debug_linux_nat
)
3850 fprintf_unfiltered (gdb_stdlog
,
3851 "RSRL: resuming stopped-resumed LWP %s\n",
3852 target_pid_to_str (lp
->ptid
));
3854 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3855 lp
->step
, TARGET_SIGNAL_0
);
3857 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
3858 lp
->stopped_by_watchpoint
= 0;
3865 linux_nat_wait (struct target_ops
*ops
,
3866 ptid_t ptid
, struct target_waitstatus
*ourstatus
,
3871 if (debug_linux_nat
)
3872 fprintf_unfiltered (gdb_stdlog
,
3873 "linux_nat_wait: [%s]\n", target_pid_to_str (ptid
));
3875 /* Flush the async file first. */
3876 if (target_can_async_p ())
3877 async_file_flush ();
3879 /* Resume LWPs that are currently stopped without any pending status
3880 to report, but are resumed from the core's perspective. LWPs get
3881 in this state if we find them stopping at a time we're not
3882 interested in reporting the event (target_wait on a
3883 specific_process, for example, see linux_nat_wait_1), and
3884 meanwhile the event became uninteresting. Don't bother resuming
3885 LWPs we're not going to wait for if they'd stop immediately. */
3887 iterate_over_lwps (minus_one_ptid
, resume_stopped_resumed_lwps
, &ptid
);
3889 event_ptid
= linux_nat_wait_1 (ops
, ptid
, ourstatus
, target_options
);
3891 /* If we requested any event, and something came out, assume there
3892 may be more. If we requested a specific lwp or process, also
3893 assume there may be more. */
3894 if (target_can_async_p ()
3895 && (ourstatus
->kind
!= TARGET_WAITKIND_IGNORE
3896 || !ptid_equal (ptid
, minus_one_ptid
)))
3899 /* Get ready for the next event. */
3900 if (target_can_async_p ())
3901 target_async (inferior_event_handler
, 0);
3907 kill_callback (struct lwp_info
*lp
, void *data
)
3909 /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */
3912 kill (GET_LWP (lp
->ptid
), SIGKILL
);
3913 if (debug_linux_nat
)
3914 fprintf_unfiltered (gdb_stdlog
,
3915 "KC: kill (SIGKILL) %s, 0, 0 (%s)\n",
3916 target_pid_to_str (lp
->ptid
),
3917 errno
? safe_strerror (errno
) : "OK");
3919 /* Some kernels ignore even SIGKILL for processes under ptrace. */
3922 ptrace (PTRACE_KILL
, GET_LWP (lp
->ptid
), 0, 0);
3923 if (debug_linux_nat
)
3924 fprintf_unfiltered (gdb_stdlog
,
3925 "KC: PTRACE_KILL %s, 0, 0 (%s)\n",
3926 target_pid_to_str (lp
->ptid
),
3927 errno
? safe_strerror (errno
) : "OK");
3933 kill_wait_callback (struct lwp_info
*lp
, void *data
)
3937 /* We must make sure that there are no pending events (delayed
3938 SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current
3939 program doesn't interfere with any following debugging session. */
3941 /* For cloned processes we must check both with __WCLONE and
3942 without, since the exit status of a cloned process isn't reported
3948 pid
= my_waitpid (GET_LWP (lp
->ptid
), NULL
, __WCLONE
);
3949 if (pid
!= (pid_t
) -1)
3951 if (debug_linux_nat
)
3952 fprintf_unfiltered (gdb_stdlog
,
3953 "KWC: wait %s received unknown.\n",
3954 target_pid_to_str (lp
->ptid
));
3955 /* The Linux kernel sometimes fails to kill a thread
3956 completely after PTRACE_KILL; that goes from the stop
3957 point in do_fork out to the one in
3958 get_signal_to_deliever and waits again. So kill it
3960 kill_callback (lp
, NULL
);
3963 while (pid
== GET_LWP (lp
->ptid
));
3965 gdb_assert (pid
== -1 && errno
== ECHILD
);
3970 pid
= my_waitpid (GET_LWP (lp
->ptid
), NULL
, 0);
3971 if (pid
!= (pid_t
) -1)
3973 if (debug_linux_nat
)
3974 fprintf_unfiltered (gdb_stdlog
,
3975 "KWC: wait %s received unk.\n",
3976 target_pid_to_str (lp
->ptid
));
3977 /* See the call to kill_callback above. */
3978 kill_callback (lp
, NULL
);
3981 while (pid
== GET_LWP (lp
->ptid
));
3983 gdb_assert (pid
== -1 && errno
== ECHILD
);
3988 linux_nat_kill (struct target_ops
*ops
)
3990 struct target_waitstatus last
;
3994 /* If we're stopped while forking and we haven't followed yet,
3995 kill the other task. We need to do this first because the
3996 parent will be sleeping if this is a vfork. */
3998 get_last_target_status (&last_ptid
, &last
);
4000 if (last
.kind
== TARGET_WAITKIND_FORKED
4001 || last
.kind
== TARGET_WAITKIND_VFORKED
)
4003 ptrace (PT_KILL
, PIDGET (last
.value
.related_pid
), 0, 0);
4007 if (forks_exist_p ())
4008 linux_fork_killall ();
4011 ptid_t ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
4013 /* Stop all threads before killing them, since ptrace requires
4014 that the thread is stopped to sucessfully PTRACE_KILL. */
4015 iterate_over_lwps (ptid
, stop_callback
, NULL
);
4016 /* ... and wait until all of them have reported back that
4017 they're no longer running. */
4018 iterate_over_lwps (ptid
, stop_wait_callback
, NULL
);
4020 /* Kill all LWP's ... */
4021 iterate_over_lwps (ptid
, kill_callback
, NULL
);
4023 /* ... and wait until we've flushed all events. */
4024 iterate_over_lwps (ptid
, kill_wait_callback
, NULL
);
4027 target_mourn_inferior ();
4031 linux_nat_mourn_inferior (struct target_ops
*ops
)
4033 purge_lwp_list (ptid_get_pid (inferior_ptid
));
4035 if (! forks_exist_p ())
4036 /* Normal case, no other forks available. */
4037 linux_ops
->to_mourn_inferior (ops
);
4039 /* Multi-fork case. The current inferior_ptid has exited, but
4040 there are other viable forks to debug. Delete the exiting
4041 one and context-switch to the first available. */
4042 linux_fork_mourn_inferior ();
4045 /* Convert a native/host siginfo object, into/from the siginfo in the
4046 layout of the inferiors' architecture. */
4049 siginfo_fixup (struct siginfo
*siginfo
, gdb_byte
*inf_siginfo
, int direction
)
4053 if (linux_nat_siginfo_fixup
!= NULL
)
4054 done
= linux_nat_siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4056 /* If there was no callback, or the callback didn't do anything,
4057 then just do a straight memcpy. */
4061 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
4063 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
4068 linux_xfer_siginfo (struct target_ops
*ops
, enum target_object object
,
4069 const char *annex
, gdb_byte
*readbuf
,
4070 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
4073 struct siginfo siginfo
;
4074 gdb_byte inf_siginfo
[sizeof (struct siginfo
)];
4076 gdb_assert (object
== TARGET_OBJECT_SIGNAL_INFO
);
4077 gdb_assert (readbuf
|| writebuf
);
4079 pid
= GET_LWP (inferior_ptid
);
4081 pid
= GET_PID (inferior_ptid
);
4083 if (offset
> sizeof (siginfo
))
4087 ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
);
4091 /* When GDB is built as a 64-bit application, ptrace writes into
4092 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4093 inferior with a 64-bit GDB should look the same as debugging it
4094 with a 32-bit GDB, we need to convert it. GDB core always sees
4095 the converted layout, so any read/write will have to be done
4097 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4099 if (offset
+ len
> sizeof (siginfo
))
4100 len
= sizeof (siginfo
) - offset
;
4102 if (readbuf
!= NULL
)
4103 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4106 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4108 /* Convert back to ptrace layout before flushing it out. */
4109 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4112 ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
);
4121 linux_nat_xfer_partial (struct target_ops
*ops
, enum target_object object
,
4122 const char *annex
, gdb_byte
*readbuf
,
4123 const gdb_byte
*writebuf
,
4124 ULONGEST offset
, LONGEST len
)
4126 struct cleanup
*old_chain
;
4129 if (object
== TARGET_OBJECT_SIGNAL_INFO
)
4130 return linux_xfer_siginfo (ops
, object
, annex
, readbuf
, writebuf
,
4133 /* The target is connected but no live inferior is selected. Pass
4134 this request down to a lower stratum (e.g., the executable
4136 if (object
== TARGET_OBJECT_MEMORY
&& ptid_equal (inferior_ptid
, null_ptid
))
4139 old_chain
= save_inferior_ptid ();
4141 if (is_lwp (inferior_ptid
))
4142 inferior_ptid
= pid_to_ptid (GET_LWP (inferior_ptid
));
4144 xfer
= linux_ops
->to_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
4147 do_cleanups (old_chain
);
4152 linux_thread_alive (ptid_t ptid
)
4156 gdb_assert (is_lwp (ptid
));
4158 /* Send signal 0 instead of anything ptrace, because ptracing a
4159 running thread errors out claiming that the thread doesn't
4161 err
= kill_lwp (GET_LWP (ptid
), 0);
4163 if (debug_linux_nat
)
4164 fprintf_unfiltered (gdb_stdlog
,
4165 "LLTA: KILL(SIG0) %s (%s)\n",
4166 target_pid_to_str (ptid
),
4167 err
? safe_strerror (tmp_errno
) : "OK");
4176 linux_nat_thread_alive (struct target_ops
*ops
, ptid_t ptid
)
4178 return linux_thread_alive (ptid
);
4182 linux_nat_pid_to_str (struct target_ops
*ops
, ptid_t ptid
)
4184 static char buf
[64];
4187 && (GET_PID (ptid
) != GET_LWP (ptid
)
4188 || num_lwps (GET_PID (ptid
)) > 1))
4190 snprintf (buf
, sizeof (buf
), "LWP %ld", GET_LWP (ptid
));
4194 return normal_pid_to_str (ptid
);
4198 linux_nat_thread_name (struct thread_info
*thr
)
4200 int pid
= ptid_get_pid (thr
->ptid
);
4201 long lwp
= ptid_get_lwp (thr
->ptid
);
4202 #define FORMAT "/proc/%d/task/%ld/comm"
4203 char buf
[sizeof (FORMAT
) + 30];
4205 char *result
= NULL
;
4207 snprintf (buf
, sizeof (buf
), FORMAT
, pid
, lwp
);
4208 comm_file
= fopen (buf
, "r");
4211 /* Not exported by the kernel, so we define it here. */
4213 static char line
[COMM_LEN
+ 1];
4215 if (fgets (line
, sizeof (line
), comm_file
))
4217 char *nl
= strchr (line
, '\n');
4234 /* Accepts an integer PID; Returns a string representing a file that
4235 can be opened to get the symbols for the child process. */
4238 linux_child_pid_to_exec_file (int pid
)
4240 char *name1
, *name2
;
4242 name1
= xmalloc (MAXPATHLEN
);
4243 name2
= xmalloc (MAXPATHLEN
);
4244 make_cleanup (xfree
, name1
);
4245 make_cleanup (xfree
, name2
);
4246 memset (name2
, 0, MAXPATHLEN
);
4248 sprintf (name1
, "/proc/%d/exe", pid
);
4249 if (readlink (name1
, name2
, MAXPATHLEN
) > 0)
4255 /* Service function for corefiles and info proc. */
4258 read_mapping (FILE *mapfile
,
4263 char *device
, long long *inode
, char *filename
)
4265 int ret
= fscanf (mapfile
, "%llx-%llx %s %llx %s %llx",
4266 addr
, endaddr
, permissions
, offset
, device
, inode
);
4269 if (ret
> 0 && ret
!= EOF
)
4271 /* Eat everything up to EOL for the filename. This will prevent
4272 weird filenames (such as one with embedded whitespace) from
4273 confusing this code. It also makes this code more robust in
4274 respect to annotations the kernel may add after the filename.
4276 Note the filename is used for informational purposes
4278 ret
+= fscanf (mapfile
, "%[^\n]\n", filename
);
4281 return (ret
!= 0 && ret
!= EOF
);
4284 /* Fills the "to_find_memory_regions" target vector. Lists the memory
4285 regions in the inferior for a corefile. */
4288 linux_nat_find_memory_regions (find_memory_region_ftype func
, void *obfd
)
4290 int pid
= PIDGET (inferior_ptid
);
4291 char mapsfilename
[MAXPATHLEN
];
4293 long long addr
, endaddr
, size
, offset
, inode
;
4294 char permissions
[8], device
[8], filename
[MAXPATHLEN
];
4295 int read
, write
, exec
;
4296 struct cleanup
*cleanup
;
4298 /* Compose the filename for the /proc memory map, and open it. */
4299 sprintf (mapsfilename
, "/proc/%d/maps", pid
);
4300 if ((mapsfile
= fopen (mapsfilename
, "r")) == NULL
)
4301 error (_("Could not open %s."), mapsfilename
);
4302 cleanup
= make_cleanup_fclose (mapsfile
);
4305 fprintf_filtered (gdb_stdout
,
4306 "Reading memory regions from %s\n", mapsfilename
);
4308 /* Now iterate until end-of-file. */
4309 while (read_mapping (mapsfile
, &addr
, &endaddr
, &permissions
[0],
4310 &offset
, &device
[0], &inode
, &filename
[0]))
4312 size
= endaddr
- addr
;
4314 /* Get the segment's permissions. */
4315 read
= (strchr (permissions
, 'r') != 0);
4316 write
= (strchr (permissions
, 'w') != 0);
4317 exec
= (strchr (permissions
, 'x') != 0);
4321 fprintf_filtered (gdb_stdout
,
4322 "Save segment, %s bytes at %s (%c%c%c)",
4323 plongest (size
), paddress (target_gdbarch
, addr
),
4325 write
? 'w' : ' ', exec
? 'x' : ' ');
4327 fprintf_filtered (gdb_stdout
, " for %s", filename
);
4328 fprintf_filtered (gdb_stdout
, "\n");
4331 /* Invoke the callback function to create the corefile
4333 func (addr
, size
, read
, write
, exec
, obfd
);
4335 do_cleanups (cleanup
);
4340 find_signalled_thread (struct thread_info
*info
, void *data
)
4342 if (info
->suspend
.stop_signal
!= TARGET_SIGNAL_0
4343 && ptid_get_pid (info
->ptid
) == ptid_get_pid (inferior_ptid
))
4349 static enum target_signal
4350 find_stop_signal (void)
4352 struct thread_info
*info
=
4353 iterate_over_threads (find_signalled_thread
, NULL
);
4356 return info
->suspend
.stop_signal
;
4358 return TARGET_SIGNAL_0
;
4361 /* Records the thread's register state for the corefile note
4365 linux_nat_do_thread_registers (bfd
*obfd
, ptid_t ptid
,
4366 char *note_data
, int *note_size
,
4367 enum target_signal stop_signal
)
4369 unsigned long lwp
= ptid_get_lwp (ptid
);
4370 struct gdbarch
*gdbarch
= target_gdbarch
;
4371 struct regcache
*regcache
= get_thread_arch_regcache (ptid
, gdbarch
);
4372 const struct regset
*regset
;
4374 struct cleanup
*old_chain
;
4375 struct core_regset_section
*sect_list
;
4378 old_chain
= save_inferior_ptid ();
4379 inferior_ptid
= ptid
;
4380 target_fetch_registers (regcache
, -1);
4381 do_cleanups (old_chain
);
4383 core_regset_p
= gdbarch_regset_from_core_section_p (gdbarch
);
4384 sect_list
= gdbarch_core_regset_sections (gdbarch
);
4386 /* The loop below uses the new struct core_regset_section, which stores
4387 the supported section names and sizes for the core file. Note that
4388 note PRSTATUS needs to be treated specially. But the other notes are
4389 structurally the same, so they can benefit from the new struct. */
4390 if (core_regset_p
&& sect_list
!= NULL
)
4391 while (sect_list
->sect_name
!= NULL
)
4393 regset
= gdbarch_regset_from_core_section (gdbarch
,
4394 sect_list
->sect_name
,
4396 gdb_assert (regset
&& regset
->collect_regset
);
4397 gdb_regset
= xmalloc (sect_list
->size
);
4398 regset
->collect_regset (regset
, regcache
, -1,
4399 gdb_regset
, sect_list
->size
);
4401 if (strcmp (sect_list
->sect_name
, ".reg") == 0)
4402 note_data
= (char *) elfcore_write_prstatus
4403 (obfd
, note_data
, note_size
,
4404 lwp
, target_signal_to_host (stop_signal
),
4407 note_data
= (char *) elfcore_write_register_note
4408 (obfd
, note_data
, note_size
,
4409 sect_list
->sect_name
, gdb_regset
,
4415 /* For architectures that does not have the struct core_regset_section
4416 implemented, we use the old method. When all the architectures have
4417 the new support, the code below should be deleted. */
4420 gdb_gregset_t gregs
;
4421 gdb_fpregset_t fpregs
;
4424 && (regset
= gdbarch_regset_from_core_section (gdbarch
, ".reg",
4426 != NULL
&& regset
->collect_regset
!= NULL
)
4427 regset
->collect_regset (regset
, regcache
, -1,
4428 &gregs
, sizeof (gregs
));
4430 fill_gregset (regcache
, &gregs
, -1);
4432 note_data
= (char *) elfcore_write_prstatus
4433 (obfd
, note_data
, note_size
, lwp
, target_signal_to_host (stop_signal
),
4437 && (regset
= gdbarch_regset_from_core_section (gdbarch
, ".reg2",
4439 != NULL
&& regset
->collect_regset
!= NULL
)
4440 regset
->collect_regset (regset
, regcache
, -1,
4441 &fpregs
, sizeof (fpregs
));
4443 fill_fpregset (regcache
, &fpregs
, -1);
4445 note_data
= (char *) elfcore_write_prfpreg (obfd
,
4448 &fpregs
, sizeof (fpregs
));
4454 struct linux_nat_corefile_thread_data
4460 enum target_signal stop_signal
;
4463 /* Called by gdbthread.c once per thread. Records the thread's
4464 register state for the corefile note section. */
4467 linux_nat_corefile_thread_callback (struct lwp_info
*ti
, void *data
)
4469 struct linux_nat_corefile_thread_data
*args
= data
;
4471 args
->note_data
= linux_nat_do_thread_registers (args
->obfd
,
4481 /* Enumerate spufs IDs for process PID. */
4484 iterate_over_spus (int pid
, void (*callback
) (void *, int), void *data
)
4488 struct dirent
*entry
;
4490 xsnprintf (path
, sizeof path
, "/proc/%d/fd", pid
);
4491 dir
= opendir (path
);
4496 while ((entry
= readdir (dir
)) != NULL
)
4502 fd
= atoi (entry
->d_name
);
4506 xsnprintf (path
, sizeof path
, "/proc/%d/fd/%d", pid
, fd
);
4507 if (stat (path
, &st
) != 0)
4509 if (!S_ISDIR (st
.st_mode
))
4512 if (statfs (path
, &stfs
) != 0)
4514 if (stfs
.f_type
!= SPUFS_MAGIC
)
4517 callback (data
, fd
);
4523 /* Generate corefile notes for SPU contexts. */
4525 struct linux_spu_corefile_data
4533 linux_spu_corefile_callback (void *data
, int fd
)
4535 struct linux_spu_corefile_data
*args
= data
;
4538 static const char *spu_files
[] =
4560 for (i
= 0; i
< sizeof (spu_files
) / sizeof (spu_files
[0]); i
++)
4562 char annex
[32], note_name
[32];
4566 xsnprintf (annex
, sizeof annex
, "%d/%s", fd
, spu_files
[i
]);
4567 spu_len
= target_read_alloc (¤t_target
, TARGET_OBJECT_SPU
,
4571 xsnprintf (note_name
, sizeof note_name
, "SPU/%s", annex
);
4572 args
->note_data
= elfcore_write_note (args
->obfd
, args
->note_data
,
4573 args
->note_size
, note_name
,
4574 NT_SPU
, spu_data
, spu_len
);
4581 linux_spu_make_corefile_notes (bfd
*obfd
, char *note_data
, int *note_size
)
4583 struct linux_spu_corefile_data args
;
4586 args
.note_data
= note_data
;
4587 args
.note_size
= note_size
;
4589 iterate_over_spus (PIDGET (inferior_ptid
),
4590 linux_spu_corefile_callback
, &args
);
4592 return args
.note_data
;
4595 /* Fills the "to_make_corefile_note" target vector. Builds the note
4596 section for a corefile, and returns it in a malloc buffer. */
4599 linux_nat_make_corefile_notes (bfd
*obfd
, int *note_size
)
4601 struct linux_nat_corefile_thread_data thread_args
;
4602 /* The variable size must be >= sizeof (prpsinfo_t.pr_fname). */
4603 char fname
[16] = { '\0' };
4604 /* The variable size must be >= sizeof (prpsinfo_t.pr_psargs). */
4605 char psargs
[80] = { '\0' };
4606 char *note_data
= NULL
;
4607 ptid_t filter
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
4611 if (get_exec_file (0))
4613 strncpy (fname
, lbasename (get_exec_file (0)), sizeof (fname
));
4614 strncpy (psargs
, get_exec_file (0), sizeof (psargs
));
4615 if (get_inferior_args ())
4618 char *psargs_end
= psargs
+ sizeof (psargs
);
4620 /* linux_elfcore_write_prpsinfo () handles zero unterminated
4622 string_end
= memchr (psargs
, 0, sizeof (psargs
));
4623 if (string_end
!= NULL
)
4625 *string_end
++ = ' ';
4626 strncpy (string_end
, get_inferior_args (),
4627 psargs_end
- string_end
);
4630 note_data
= (char *) elfcore_write_prpsinfo (obfd
,
4632 note_size
, fname
, psargs
);
4635 /* Dump information for threads. */
4636 thread_args
.obfd
= obfd
;
4637 thread_args
.note_data
= note_data
;
4638 thread_args
.note_size
= note_size
;
4639 thread_args
.num_notes
= 0;
4640 thread_args
.stop_signal
= find_stop_signal ();
4641 iterate_over_lwps (filter
, linux_nat_corefile_thread_callback
, &thread_args
);
4642 gdb_assert (thread_args
.num_notes
!= 0);
4643 note_data
= thread_args
.note_data
;
4645 auxv_len
= target_read_alloc (¤t_target
, TARGET_OBJECT_AUXV
,
4649 note_data
= elfcore_write_note (obfd
, note_data
, note_size
,
4650 "CORE", NT_AUXV
, auxv
, auxv_len
);
4654 note_data
= linux_spu_make_corefile_notes (obfd
, note_data
, note_size
);
4656 make_cleanup (xfree
, note_data
);
4660 /* Implement the "info proc" command. */
4663 linux_nat_info_proc_cmd (char *args
, int from_tty
)
4665 /* A long is used for pid instead of an int to avoid a loss of precision
4666 compiler warning from the output of strtoul. */
4667 long pid
= PIDGET (inferior_ptid
);
4670 char buffer
[MAXPATHLEN
];
4671 char fname1
[MAXPATHLEN
], fname2
[MAXPATHLEN
];
4683 /* Break up 'args' into an argv array. */
4684 argv
= gdb_buildargv (args
);
4685 make_cleanup_freeargv (argv
);
4687 while (argv
!= NULL
&& *argv
!= NULL
)
4689 if (isdigit (argv
[0][0]))
4691 pid
= strtoul (argv
[0], NULL
, 10);
4693 else if (strncmp (argv
[0], "mappings", strlen (argv
[0])) == 0)
4697 else if (strcmp (argv
[0], "status") == 0)
4701 else if (strcmp (argv
[0], "stat") == 0)
4705 else if (strcmp (argv
[0], "cmd") == 0)
4709 else if (strncmp (argv
[0], "exe", strlen (argv
[0])) == 0)
4713 else if (strcmp (argv
[0], "cwd") == 0)
4717 else if (strncmp (argv
[0], "all", strlen (argv
[0])) == 0)
4723 /* [...] (future options here). */
4728 error (_("No current process: you must name one."));
4730 sprintf (fname1
, "/proc/%ld", pid
);
4731 if (stat (fname1
, &dummy
) != 0)
4732 error (_("No /proc directory: '%s'"), fname1
);
4734 printf_filtered (_("process %ld\n"), pid
);
4735 if (cmdline_f
|| all
)
4737 sprintf (fname1
, "/proc/%ld/cmdline", pid
);
4738 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4740 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
4742 if (fgets (buffer
, sizeof (buffer
), procfile
))
4743 printf_filtered ("cmdline = '%s'\n", buffer
);
4745 warning (_("unable to read '%s'"), fname1
);
4746 do_cleanups (cleanup
);
4749 warning (_("unable to open /proc file '%s'"), fname1
);
4753 sprintf (fname1
, "/proc/%ld/cwd", pid
);
4754 memset (fname2
, 0, sizeof (fname2
));
4755 if (readlink (fname1
, fname2
, sizeof (fname2
)) > 0)
4756 printf_filtered ("cwd = '%s'\n", fname2
);
4758 warning (_("unable to read link '%s'"), fname1
);
4762 sprintf (fname1
, "/proc/%ld/exe", pid
);
4763 memset (fname2
, 0, sizeof (fname2
));
4764 if (readlink (fname1
, fname2
, sizeof (fname2
)) > 0)
4765 printf_filtered ("exe = '%s'\n", fname2
);
4767 warning (_("unable to read link '%s'"), fname1
);
4769 if (mappings_f
|| all
)
4771 sprintf (fname1
, "/proc/%ld/maps", pid
);
4772 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4774 long long addr
, endaddr
, size
, offset
, inode
;
4775 char permissions
[8], device
[8], filename
[MAXPATHLEN
];
4776 struct cleanup
*cleanup
;
4778 cleanup
= make_cleanup_fclose (procfile
);
4779 printf_filtered (_("Mapped address spaces:\n\n"));
4780 if (gdbarch_addr_bit (target_gdbarch
) == 32)
4782 printf_filtered ("\t%10s %10s %10s %10s %7s\n",
4785 " Size", " Offset", "objfile");
4789 printf_filtered (" %18s %18s %10s %10s %7s\n",
4792 " Size", " Offset", "objfile");
4795 while (read_mapping (procfile
, &addr
, &endaddr
, &permissions
[0],
4796 &offset
, &device
[0], &inode
, &filename
[0]))
4798 size
= endaddr
- addr
;
4800 /* FIXME: carlton/2003-08-27: Maybe the printf_filtered
4801 calls here (and possibly above) should be abstracted
4802 out into their own functions? Andrew suggests using
4803 a generic local_address_string instead to print out
4804 the addresses; that makes sense to me, too. */
4806 if (gdbarch_addr_bit (target_gdbarch
) == 32)
4808 printf_filtered ("\t%#10lx %#10lx %#10x %#10x %7s\n",
4809 (unsigned long) addr
, /* FIXME: pr_addr */
4810 (unsigned long) endaddr
,
4812 (unsigned int) offset
,
4813 filename
[0] ? filename
: "");
4817 printf_filtered (" %#18lx %#18lx %#10x %#10x %7s\n",
4818 (unsigned long) addr
, /* FIXME: pr_addr */
4819 (unsigned long) endaddr
,
4821 (unsigned int) offset
,
4822 filename
[0] ? filename
: "");
4826 do_cleanups (cleanup
);
4829 warning (_("unable to open /proc file '%s'"), fname1
);
4831 if (status_f
|| all
)
4833 sprintf (fname1
, "/proc/%ld/status", pid
);
4834 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4836 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
4838 while (fgets (buffer
, sizeof (buffer
), procfile
) != NULL
)
4839 puts_filtered (buffer
);
4840 do_cleanups (cleanup
);
4843 warning (_("unable to open /proc file '%s'"), fname1
);
4847 sprintf (fname1
, "/proc/%ld/stat", pid
);
4848 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4853 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
4855 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4856 printf_filtered (_("Process: %d\n"), itmp
);
4857 if (fscanf (procfile
, "(%[^)]) ", &buffer
[0]) > 0)
4858 printf_filtered (_("Exec file: %s\n"), buffer
);
4859 if (fscanf (procfile
, "%c ", &ctmp
) > 0)
4860 printf_filtered (_("State: %c\n"), ctmp
);
4861 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4862 printf_filtered (_("Parent process: %d\n"), itmp
);
4863 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4864 printf_filtered (_("Process group: %d\n"), itmp
);
4865 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4866 printf_filtered (_("Session id: %d\n"), itmp
);
4867 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4868 printf_filtered (_("TTY: %d\n"), itmp
);
4869 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4870 printf_filtered (_("TTY owner process group: %d\n"), itmp
);
4871 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4872 printf_filtered (_("Flags: 0x%lx\n"), ltmp
);
4873 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4874 printf_filtered (_("Minor faults (no memory page): %lu\n"),
4875 (unsigned long) ltmp
);
4876 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4877 printf_filtered (_("Minor faults, children: %lu\n"),
4878 (unsigned long) ltmp
);
4879 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4880 printf_filtered (_("Major faults (memory page faults): %lu\n"),
4881 (unsigned long) ltmp
);
4882 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4883 printf_filtered (_("Major faults, children: %lu\n"),
4884 (unsigned long) ltmp
);
4885 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4886 printf_filtered (_("utime: %ld\n"), ltmp
);
4887 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4888 printf_filtered (_("stime: %ld\n"), ltmp
);
4889 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4890 printf_filtered (_("utime, children: %ld\n"), ltmp
);
4891 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4892 printf_filtered (_("stime, children: %ld\n"), ltmp
);
4893 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4894 printf_filtered (_("jiffies remaining in current "
4895 "time slice: %ld\n"), ltmp
);
4896 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4897 printf_filtered (_("'nice' value: %ld\n"), ltmp
);
4898 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4899 printf_filtered (_("jiffies until next timeout: %lu\n"),
4900 (unsigned long) ltmp
);
4901 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4902 printf_filtered (_("jiffies until next SIGALRM: %lu\n"),
4903 (unsigned long) ltmp
);
4904 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4905 printf_filtered (_("start time (jiffies since "
4906 "system boot): %ld\n"), ltmp
);
4907 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4908 printf_filtered (_("Virtual memory size: %lu\n"),
4909 (unsigned long) ltmp
);
4910 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4911 printf_filtered (_("Resident set size: %lu\n"),
4912 (unsigned long) ltmp
);
4913 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4914 printf_filtered (_("rlim: %lu\n"), (unsigned long) ltmp
);
4915 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4916 printf_filtered (_("Start of text: 0x%lx\n"), ltmp
);
4917 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4918 printf_filtered (_("End of text: 0x%lx\n"), ltmp
);
4919 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4920 printf_filtered (_("Start of stack: 0x%lx\n"), ltmp
);
4921 #if 0 /* Don't know how architecture-dependent the rest is...
4922 Anyway the signal bitmap info is available from "status". */
4923 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
4924 printf_filtered (_("Kernel stack pointer: 0x%lx\n"), ltmp
);
4925 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
4926 printf_filtered (_("Kernel instr pointer: 0x%lx\n"), ltmp
);
4927 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4928 printf_filtered (_("Pending signals bitmap: 0x%lx\n"), ltmp
);
4929 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4930 printf_filtered (_("Blocked signals bitmap: 0x%lx\n"), ltmp
);
4931 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4932 printf_filtered (_("Ignored signals bitmap: 0x%lx\n"), ltmp
);
4933 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4934 printf_filtered (_("Catched signals bitmap: 0x%lx\n"), ltmp
);
4935 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
4936 printf_filtered (_("wchan (system call): 0x%lx\n"), ltmp
);
4938 do_cleanups (cleanup
);
4941 warning (_("unable to open /proc file '%s'"), fname1
);
4945 /* Implement the to_xfer_partial interface for memory reads using the /proc
4946 filesystem. Because we can use a single read() call for /proc, this
4947 can be much more efficient than banging away at PTRACE_PEEKTEXT,
4948 but it doesn't support writes. */
4951 linux_proc_xfer_partial (struct target_ops
*ops
, enum target_object object
,
4952 const char *annex
, gdb_byte
*readbuf
,
4953 const gdb_byte
*writebuf
,
4954 ULONGEST offset
, LONGEST len
)
4960 if (object
!= TARGET_OBJECT_MEMORY
|| !readbuf
)
4963 /* Don't bother for one word. */
4964 if (len
< 3 * sizeof (long))
4967 /* We could keep this file open and cache it - possibly one per
4968 thread. That requires some juggling, but is even faster. */
4969 sprintf (filename
, "/proc/%d/mem", PIDGET (inferior_ptid
));
4970 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4974 /* If pread64 is available, use it. It's faster if the kernel
4975 supports it (only one syscall), and it's 64-bit safe even on
4976 32-bit platforms (for instance, SPARC debugging a SPARC64
4979 if (pread64 (fd
, readbuf
, len
, offset
) != len
)
4981 if (lseek (fd
, offset
, SEEK_SET
) == -1 || read (fd
, readbuf
, len
) != len
)
4992 /* Enumerate spufs IDs for process PID. */
4994 spu_enumerate_spu_ids (int pid
, gdb_byte
*buf
, ULONGEST offset
, LONGEST len
)
4996 enum bfd_endian byte_order
= gdbarch_byte_order (target_gdbarch
);
4998 LONGEST written
= 0;
5001 struct dirent
*entry
;
5003 xsnprintf (path
, sizeof path
, "/proc/%d/fd", pid
);
5004 dir
= opendir (path
);
5009 while ((entry
= readdir (dir
)) != NULL
)
5015 fd
= atoi (entry
->d_name
);
5019 xsnprintf (path
, sizeof path
, "/proc/%d/fd/%d", pid
, fd
);
5020 if (stat (path
, &st
) != 0)
5022 if (!S_ISDIR (st
.st_mode
))
5025 if (statfs (path
, &stfs
) != 0)
5027 if (stfs
.f_type
!= SPUFS_MAGIC
)
5030 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
5032 store_unsigned_integer (buf
+ pos
- offset
, 4, byte_order
, fd
);
5042 /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU
5043 object type, using the /proc file system. */
5045 linux_proc_xfer_spu (struct target_ops
*ops
, enum target_object object
,
5046 const char *annex
, gdb_byte
*readbuf
,
5047 const gdb_byte
*writebuf
,
5048 ULONGEST offset
, LONGEST len
)
5053 int pid
= PIDGET (inferior_ptid
);
5060 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5063 xsnprintf (buf
, sizeof buf
, "/proc/%d/fd/%s", pid
, annex
);
5064 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5069 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5076 ret
= write (fd
, writebuf
, (size_t) len
);
5078 ret
= read (fd
, readbuf
, (size_t) len
);
5085 /* Parse LINE as a signal set and add its set bits to SIGS. */
5088 add_line_to_sigset (const char *line
, sigset_t
*sigs
)
5090 int len
= strlen (line
) - 1;
5094 if (line
[len
] != '\n')
5095 error (_("Could not parse signal set: %s"), line
);
5103 if (*p
>= '0' && *p
<= '9')
5105 else if (*p
>= 'a' && *p
<= 'f')
5106 digit
= *p
- 'a' + 10;
5108 error (_("Could not parse signal set: %s"), line
);
5113 sigaddset (sigs
, signum
+ 1);
5115 sigaddset (sigs
, signum
+ 2);
5117 sigaddset (sigs
, signum
+ 3);
5119 sigaddset (sigs
, signum
+ 4);
5125 /* Find process PID's pending signals from /proc/pid/status and set
5129 linux_proc_pending_signals (int pid
, sigset_t
*pending
,
5130 sigset_t
*blocked
, sigset_t
*ignored
)
5133 char buffer
[MAXPATHLEN
], fname
[MAXPATHLEN
];
5134 struct cleanup
*cleanup
;
5136 sigemptyset (pending
);
5137 sigemptyset (blocked
);
5138 sigemptyset (ignored
);
5139 sprintf (fname
, "/proc/%d/status", pid
);
5140 procfile
= fopen (fname
, "r");
5141 if (procfile
== NULL
)
5142 error (_("Could not open %s"), fname
);
5143 cleanup
= make_cleanup_fclose (procfile
);
5145 while (fgets (buffer
, MAXPATHLEN
, procfile
) != NULL
)
5147 /* Normal queued signals are on the SigPnd line in the status
5148 file. However, 2.6 kernels also have a "shared" pending
5149 queue for delivering signals to a thread group, so check for
5152 Unfortunately some Red Hat kernels include the shared pending
5153 queue but not the ShdPnd status field. */
5155 if (strncmp (buffer
, "SigPnd:\t", 8) == 0)
5156 add_line_to_sigset (buffer
+ 8, pending
);
5157 else if (strncmp (buffer
, "ShdPnd:\t", 8) == 0)
5158 add_line_to_sigset (buffer
+ 8, pending
);
5159 else if (strncmp (buffer
, "SigBlk:\t", 8) == 0)
5160 add_line_to_sigset (buffer
+ 8, blocked
);
5161 else if (strncmp (buffer
, "SigIgn:\t", 8) == 0)
5162 add_line_to_sigset (buffer
+ 8, ignored
);
5165 do_cleanups (cleanup
);
5169 linux_nat_xfer_osdata (struct target_ops
*ops
, enum target_object object
,
5170 const char *annex
, gdb_byte
*readbuf
,
5171 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
5173 gdb_assert (object
== TARGET_OBJECT_OSDATA
);
5175 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5179 linux_xfer_partial (struct target_ops
*ops
, enum target_object object
,
5180 const char *annex
, gdb_byte
*readbuf
,
5181 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
5185 if (object
== TARGET_OBJECT_AUXV
)
5186 return memory_xfer_auxv (ops
, object
, annex
, readbuf
, writebuf
,
5189 if (object
== TARGET_OBJECT_OSDATA
)
5190 return linux_nat_xfer_osdata (ops
, object
, annex
, readbuf
, writebuf
,
5193 if (object
== TARGET_OBJECT_SPU
)
5194 return linux_proc_xfer_spu (ops
, object
, annex
, readbuf
, writebuf
,
5197 /* GDB calculates all the addresses in possibly larget width of the address.
5198 Address width needs to be masked before its final use - either by
5199 linux_proc_xfer_partial or inf_ptrace_xfer_partial.
5201 Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */
5203 if (object
== TARGET_OBJECT_MEMORY
)
5205 int addr_bit
= gdbarch_addr_bit (target_gdbarch
);
5207 if (addr_bit
< (sizeof (ULONGEST
) * HOST_CHAR_BIT
))
5208 offset
&= ((ULONGEST
) 1 << addr_bit
) - 1;
5211 xfer
= linux_proc_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
5216 return super_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
5220 /* Create a prototype generic GNU/Linux target. The client can override
5221 it with local methods. */
5224 linux_target_install_ops (struct target_ops
*t
)
5226 t
->to_insert_fork_catchpoint
= linux_child_insert_fork_catchpoint
;
5227 t
->to_remove_fork_catchpoint
= linux_child_remove_fork_catchpoint
;
5228 t
->to_insert_vfork_catchpoint
= linux_child_insert_vfork_catchpoint
;
5229 t
->to_remove_vfork_catchpoint
= linux_child_remove_vfork_catchpoint
;
5230 t
->to_insert_exec_catchpoint
= linux_child_insert_exec_catchpoint
;
5231 t
->to_remove_exec_catchpoint
= linux_child_remove_exec_catchpoint
;
5232 t
->to_set_syscall_catchpoint
= linux_child_set_syscall_catchpoint
;
5233 t
->to_pid_to_exec_file
= linux_child_pid_to_exec_file
;
5234 t
->to_post_startup_inferior
= linux_child_post_startup_inferior
;
5235 t
->to_post_attach
= linux_child_post_attach
;
5236 t
->to_follow_fork
= linux_child_follow_fork
;
5237 t
->to_find_memory_regions
= linux_nat_find_memory_regions
;
5238 t
->to_make_corefile_notes
= linux_nat_make_corefile_notes
;
5240 super_xfer_partial
= t
->to_xfer_partial
;
5241 t
->to_xfer_partial
= linux_xfer_partial
;
5247 struct target_ops
*t
;
5249 t
= inf_ptrace_target ();
5250 linux_target_install_ops (t
);
5256 linux_trad_target (CORE_ADDR (*register_u_offset
)(struct gdbarch
*, int, int))
5258 struct target_ops
*t
;
5260 t
= inf_ptrace_trad_target (register_u_offset
);
5261 linux_target_install_ops (t
);
5266 /* target_is_async_p implementation. */
5269 linux_nat_is_async_p (void)
5271 /* NOTE: palves 2008-03-21: We're only async when the user requests
5272 it explicitly with the "set target-async" command.
5273 Someday, linux will always be async. */
5274 return target_async_permitted
;
5277 /* target_can_async_p implementation. */
5280 linux_nat_can_async_p (void)
5282 /* NOTE: palves 2008-03-21: We're only async when the user requests
5283 it explicitly with the "set target-async" command.
5284 Someday, linux will always be async. */
5285 return target_async_permitted
;
5289 linux_nat_supports_non_stop (void)
5294 /* True if we want to support multi-process. To be removed when GDB
5295 supports multi-exec. */
5297 int linux_multi_process
= 1;
5300 linux_nat_supports_multi_process (void)
5302 return linux_multi_process
;
5306 linux_nat_supports_disable_randomization (void)
5308 #ifdef HAVE_PERSONALITY
5315 static int async_terminal_is_ours
= 1;
5317 /* target_terminal_inferior implementation. */
5320 linux_nat_terminal_inferior (void)
5322 if (!target_is_async_p ())
5324 /* Async mode is disabled. */
5325 terminal_inferior ();
5329 terminal_inferior ();
5331 /* Calls to target_terminal_*() are meant to be idempotent. */
5332 if (!async_terminal_is_ours
)
5335 delete_file_handler (input_fd
);
5336 async_terminal_is_ours
= 0;
5340 /* target_terminal_ours implementation. */
5343 linux_nat_terminal_ours (void)
5345 if (!target_is_async_p ())
5347 /* Async mode is disabled. */
5352 /* GDB should never give the terminal to the inferior if the
5353 inferior is running in the background (run&, continue&, etc.),
5354 but claiming it sure should. */
5357 if (async_terminal_is_ours
)
5360 clear_sigint_trap ();
5361 add_file_handler (input_fd
, stdin_event_handler
, 0);
5362 async_terminal_is_ours
= 1;
5365 static void (*async_client_callback
) (enum inferior_event_type event_type
,
5367 static void *async_client_context
;
5369 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5370 so we notice when any child changes state, and notify the
5371 event-loop; it allows us to use sigsuspend in linux_nat_wait_1
5372 above to wait for the arrival of a SIGCHLD. */
5375 sigchld_handler (int signo
)
5377 int old_errno
= errno
;
5379 if (debug_linux_nat
)
5380 ui_file_write_async_safe (gdb_stdlog
,
5381 "sigchld\n", sizeof ("sigchld\n") - 1);
5383 if (signo
== SIGCHLD
5384 && linux_nat_event_pipe
[0] != -1)
5385 async_file_mark (); /* Let the event loop know that there are
5386 events to handle. */
5391 /* Callback registered with the target events file descriptor. */
5394 handle_target_event (int error
, gdb_client_data client_data
)
5396 (*async_client_callback
) (INF_REG_EVENT
, async_client_context
);
5399 /* Create/destroy the target events pipe. Returns previous state. */
5402 linux_async_pipe (int enable
)
5404 int previous
= (linux_nat_event_pipe
[0] != -1);
5406 if (previous
!= enable
)
5410 block_child_signals (&prev_mask
);
5414 if (pipe (linux_nat_event_pipe
) == -1)
5415 internal_error (__FILE__
, __LINE__
,
5416 "creating event pipe failed.");
5418 fcntl (linux_nat_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5419 fcntl (linux_nat_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5423 close (linux_nat_event_pipe
[0]);
5424 close (linux_nat_event_pipe
[1]);
5425 linux_nat_event_pipe
[0] = -1;
5426 linux_nat_event_pipe
[1] = -1;
5429 restore_child_signals_mask (&prev_mask
);
5435 /* target_async implementation. */
5438 linux_nat_async (void (*callback
) (enum inferior_event_type event_type
,
5439 void *context
), void *context
)
5441 if (callback
!= NULL
)
5443 async_client_callback
= callback
;
5444 async_client_context
= context
;
5445 if (!linux_async_pipe (1))
5447 add_file_handler (linux_nat_event_pipe
[0],
5448 handle_target_event
, NULL
);
5449 /* There may be pending events to handle. Tell the event loop
5456 async_client_callback
= callback
;
5457 async_client_context
= context
;
5458 delete_file_handler (linux_nat_event_pipe
[0]);
5459 linux_async_pipe (0);
5464 /* Stop an LWP, and push a TARGET_SIGNAL_0 stop status if no other
5468 linux_nat_stop_lwp (struct lwp_info
*lwp
, void *data
)
5472 ptid_t ptid
= lwp
->ptid
;
5474 if (debug_linux_nat
)
5475 fprintf_unfiltered (gdb_stdlog
,
5476 "LNSL: running -> suspending %s\n",
5477 target_pid_to_str (lwp
->ptid
));
5480 if (lwp
->last_resume_kind
== resume_stop
)
5482 if (debug_linux_nat
)
5483 fprintf_unfiltered (gdb_stdlog
,
5484 "linux-nat: already stopping LWP %ld at "
5486 ptid_get_lwp (lwp
->ptid
));
5490 stop_callback (lwp
, NULL
);
5491 lwp
->last_resume_kind
= resume_stop
;
5495 /* Already known to be stopped; do nothing. */
5497 if (debug_linux_nat
)
5499 if (find_thread_ptid (lwp
->ptid
)->stop_requested
)
5500 fprintf_unfiltered (gdb_stdlog
,
5501 "LNSL: already stopped/stop_requested %s\n",
5502 target_pid_to_str (lwp
->ptid
));
5504 fprintf_unfiltered (gdb_stdlog
,
5505 "LNSL: already stopped/no "
5506 "stop_requested yet %s\n",
5507 target_pid_to_str (lwp
->ptid
));
5514 linux_nat_stop (ptid_t ptid
)
5517 iterate_over_lwps (ptid
, linux_nat_stop_lwp
, NULL
);
5519 linux_ops
->to_stop (ptid
);
5523 linux_nat_close (int quitting
)
5525 /* Unregister from the event loop. */
5526 if (target_is_async_p ())
5527 target_async (NULL
, 0);
5529 if (linux_ops
->to_close
)
5530 linux_ops
->to_close (quitting
);
5533 /* When requests are passed down from the linux-nat layer to the
5534 single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are
5535 used. The address space pointer is stored in the inferior object,
5536 but the common code that is passed such ptid can't tell whether
5537 lwpid is a "main" process id or not (it assumes so). We reverse
5538 look up the "main" process id from the lwp here. */
5540 struct address_space
*
5541 linux_nat_thread_address_space (struct target_ops
*t
, ptid_t ptid
)
5543 struct lwp_info
*lwp
;
5544 struct inferior
*inf
;
5547 pid
= GET_LWP (ptid
);
5548 if (GET_LWP (ptid
) == 0)
5550 /* An (lwpid,0,0) ptid. Look up the lwp object to get at the
5552 lwp
= find_lwp_pid (ptid
);
5553 pid
= GET_PID (lwp
->ptid
);
5557 /* A (pid,lwpid,0) ptid. */
5558 pid
= GET_PID (ptid
);
5561 inf
= find_inferior_pid (pid
);
5562 gdb_assert (inf
!= NULL
);
5567 linux_nat_core_of_thread_1 (ptid_t ptid
)
5569 struct cleanup
*back_to
;
5572 char *content
= NULL
;
5575 int content_read
= 0;
5579 filename
= xstrprintf ("/proc/%d/task/%ld/stat",
5580 GET_PID (ptid
), GET_LWP (ptid
));
5581 back_to
= make_cleanup (xfree
, filename
);
5583 f
= fopen (filename
, "r");
5586 do_cleanups (back_to
);
5590 make_cleanup_fclose (f
);
5596 content
= xrealloc (content
, content_read
+ 1024);
5597 n
= fread (content
+ content_read
, 1, 1024, f
);
5601 content
[content_read
] = '\0';
5606 make_cleanup (xfree
, content
);
5608 p
= strchr (content
, '(');
5612 p
= strchr (p
, ')');
5616 /* If the first field after program name has index 0, then core number is
5617 the field with index 36. There's no constant for that anywhere. */
5619 p
= strtok_r (p
, " ", &ts
);
5620 for (i
= 0; p
!= NULL
&& i
!= 36; ++i
)
5621 p
= strtok_r (NULL
, " ", &ts
);
5623 if (p
== NULL
|| sscanf (p
, "%d", &core
) == 0)
5626 do_cleanups (back_to
);
5631 /* Return the cached value of the processor core for thread PTID. */
5634 linux_nat_core_of_thread (struct target_ops
*ops
, ptid_t ptid
)
5636 struct lwp_info
*info
= find_lwp_pid (ptid
);
5644 linux_nat_add_target (struct target_ops
*t
)
5646 /* Save the provided single-threaded target. We save this in a separate
5647 variable because another target we've inherited from (e.g. inf-ptrace)
5648 may have saved a pointer to T; we want to use it for the final
5649 process stratum target. */
5650 linux_ops_saved
= *t
;
5651 linux_ops
= &linux_ops_saved
;
5653 /* Override some methods for multithreading. */
5654 t
->to_create_inferior
= linux_nat_create_inferior
;
5655 t
->to_attach
= linux_nat_attach
;
5656 t
->to_detach
= linux_nat_detach
;
5657 t
->to_resume
= linux_nat_resume
;
5658 t
->to_wait
= linux_nat_wait
;
5659 t
->to_pass_signals
= linux_nat_pass_signals
;
5660 t
->to_xfer_partial
= linux_nat_xfer_partial
;
5661 t
->to_kill
= linux_nat_kill
;
5662 t
->to_mourn_inferior
= linux_nat_mourn_inferior
;
5663 t
->to_thread_alive
= linux_nat_thread_alive
;
5664 t
->to_pid_to_str
= linux_nat_pid_to_str
;
5665 t
->to_thread_name
= linux_nat_thread_name
;
5666 t
->to_has_thread_control
= tc_schedlock
;
5667 t
->to_thread_address_space
= linux_nat_thread_address_space
;
5668 t
->to_stopped_by_watchpoint
= linux_nat_stopped_by_watchpoint
;
5669 t
->to_stopped_data_address
= linux_nat_stopped_data_address
;
5671 t
->to_can_async_p
= linux_nat_can_async_p
;
5672 t
->to_is_async_p
= linux_nat_is_async_p
;
5673 t
->to_supports_non_stop
= linux_nat_supports_non_stop
;
5674 t
->to_async
= linux_nat_async
;
5675 t
->to_terminal_inferior
= linux_nat_terminal_inferior
;
5676 t
->to_terminal_ours
= linux_nat_terminal_ours
;
5677 t
->to_close
= linux_nat_close
;
5679 /* Methods for non-stop support. */
5680 t
->to_stop
= linux_nat_stop
;
5682 t
->to_supports_multi_process
= linux_nat_supports_multi_process
;
5684 t
->to_supports_disable_randomization
5685 = linux_nat_supports_disable_randomization
;
5687 t
->to_core_of_thread
= linux_nat_core_of_thread
;
5689 /* We don't change the stratum; this target will sit at
5690 process_stratum and thread_db will set at thread_stratum. This
5691 is a little strange, since this is a multi-threaded-capable
5692 target, but we want to be on the stack below thread_db, and we
5693 also want to be used for single-threaded processes. */
5698 /* Register a method to call whenever a new thread is attached. */
5700 linux_nat_set_new_thread (struct target_ops
*t
, void (*new_thread
) (ptid_t
))
5702 /* Save the pointer. We only support a single registered instance
5703 of the GNU/Linux native target, so we do not need to map this to
5705 linux_nat_new_thread
= new_thread
;
5708 /* Register a method that converts a siginfo object between the layout
5709 that ptrace returns, and the layout in the architecture of the
5712 linux_nat_set_siginfo_fixup (struct target_ops
*t
,
5713 int (*siginfo_fixup
) (struct siginfo
*,
5717 /* Save the pointer. */
5718 linux_nat_siginfo_fixup
= siginfo_fixup
;
5721 /* Return the saved siginfo associated with PTID. */
5723 linux_nat_get_siginfo (ptid_t ptid
)
5725 struct lwp_info
*lp
= find_lwp_pid (ptid
);
5727 gdb_assert (lp
!= NULL
);
5729 return &lp
->siginfo
;
5732 /* Provide a prototype to silence -Wmissing-prototypes. */
5733 extern initialize_file_ftype _initialize_linux_nat
;
5736 _initialize_linux_nat (void)
5738 add_info ("proc", linux_nat_info_proc_cmd
, _("\
5739 Show /proc process information about any running process.\n\
5740 Specify any process id, or use the program being debugged by default.\n\
5741 Specify any of the following keywords for detailed info:\n\
5742 mappings -- list of mapped memory regions.\n\
5743 stat -- list a bunch of random process info.\n\
5744 status -- list a different bunch of random process info.\n\
5745 all -- list all available /proc info."));
5747 add_setshow_zinteger_cmd ("lin-lwp", class_maintenance
,
5748 &debug_linux_nat
, _("\
5749 Set debugging of GNU/Linux lwp module."), _("\
5750 Show debugging of GNU/Linux lwp module."), _("\
5751 Enables printf debugging output."),
5753 show_debug_linux_nat
,
5754 &setdebuglist
, &showdebuglist
);
5756 /* Save this mask as the default. */
5757 sigprocmask (SIG_SETMASK
, NULL
, &normal_mask
);
5759 /* Install a SIGCHLD handler. */
5760 sigchld_action
.sa_handler
= sigchld_handler
;
5761 sigemptyset (&sigchld_action
.sa_mask
);
5762 sigchld_action
.sa_flags
= SA_RESTART
;
5764 /* Make it the default. */
5765 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
5767 /* Make sure we don't block SIGCHLD during a sigsuspend. */
5768 sigprocmask (SIG_SETMASK
, NULL
, &suspend_mask
);
5769 sigdelset (&suspend_mask
, SIGCHLD
);
5771 sigemptyset (&blocked_mask
);
5775 /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to
5776 the GNU/Linux Threads library and therefore doesn't really belong
5779 /* Read variable NAME in the target and return its value if found.
5780 Otherwise return zero. It is assumed that the type of the variable
5784 get_signo (const char *name
)
5786 struct minimal_symbol
*ms
;
5789 ms
= lookup_minimal_symbol (name
, NULL
, NULL
);
5793 if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms
), (gdb_byte
*) &signo
,
5794 sizeof (signo
)) != 0)
5800 /* Return the set of signals used by the threads library in *SET. */
5803 lin_thread_get_thread_signals (sigset_t
*set
)
5805 struct sigaction action
;
5806 int restart
, cancel
;
5808 sigemptyset (&blocked_mask
);
5811 restart
= get_signo ("__pthread_sig_restart");
5812 cancel
= get_signo ("__pthread_sig_cancel");
5814 /* LinuxThreads normally uses the first two RT signals, but in some legacy
5815 cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does
5816 not provide any way for the debugger to query the signal numbers -
5817 fortunately they don't change! */
5820 restart
= __SIGRTMIN
;
5823 cancel
= __SIGRTMIN
+ 1;
5825 sigaddset (set
, restart
);
5826 sigaddset (set
, cancel
);
5828 /* The GNU/Linux Threads library makes terminating threads send a
5829 special "cancel" signal instead of SIGCHLD. Make sure we catch
5830 those (to prevent them from terminating GDB itself, which is
5831 likely to be their default action) and treat them the same way as
5834 action
.sa_handler
= sigchld_handler
;
5835 sigemptyset (&action
.sa_mask
);
5836 action
.sa_flags
= SA_RESTART
;
5837 sigaction (cancel
, &action
, NULL
);
5839 /* We block the "cancel" signal throughout this code ... */
5840 sigaddset (&blocked_mask
, cancel
);
5841 sigprocmask (SIG_BLOCK
, &blocked_mask
, NULL
);
5843 /* ... except during a sigsuspend. */
5844 sigdelset (&suspend_mask
, cancel
);