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
);
1832 if (debug_linux_nat
)
1833 fprintf_unfiltered (gdb_stdlog
,
1834 "RC: PTRACE_CONT %s, 0, 0 (resume sibling)\n",
1835 target_pid_to_str (lp
->ptid
));
1838 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
1839 lp
->stopped_by_watchpoint
= 0;
1843 if (debug_linux_nat
)
1844 fprintf_unfiltered (gdb_stdlog
,
1845 "RC: Not resuming sibling %s (has pending)\n",
1846 target_pid_to_str (lp
->ptid
));
1851 if (debug_linux_nat
)
1852 fprintf_unfiltered (gdb_stdlog
,
1853 "RC: Not resuming sibling %s (not stopped)\n",
1854 target_pid_to_str (lp
->ptid
));
1859 resume_callback (struct lwp_info
*lp
, void *data
)
1866 resume_clear_callback (struct lwp_info
*lp
, void *data
)
1869 lp
->last_resume_kind
= resume_stop
;
1874 resume_set_callback (struct lwp_info
*lp
, void *data
)
1877 lp
->last_resume_kind
= resume_continue
;
1882 linux_nat_resume (struct target_ops
*ops
,
1883 ptid_t ptid
, int step
, enum target_signal signo
)
1886 struct lwp_info
*lp
;
1889 if (debug_linux_nat
)
1890 fprintf_unfiltered (gdb_stdlog
,
1891 "LLR: Preparing to %s %s, %s, inferior_ptid %s\n",
1892 step
? "step" : "resume",
1893 target_pid_to_str (ptid
),
1894 (signo
!= TARGET_SIGNAL_0
1895 ? strsignal (target_signal_to_host (signo
)) : "0"),
1896 target_pid_to_str (inferior_ptid
));
1898 block_child_signals (&prev_mask
);
1900 /* A specific PTID means `step only this process id'. */
1901 resume_many
= (ptid_equal (minus_one_ptid
, ptid
)
1902 || ptid_is_pid (ptid
));
1904 /* Mark the lwps we're resuming as resumed. */
1905 iterate_over_lwps (ptid
, resume_set_callback
, NULL
);
1907 /* See if it's the current inferior that should be handled
1910 lp
= find_lwp_pid (inferior_ptid
);
1912 lp
= find_lwp_pid (ptid
);
1913 gdb_assert (lp
!= NULL
);
1915 /* Remember if we're stepping. */
1917 lp
->last_resume_kind
= step
? resume_step
: resume_continue
;
1919 /* If we have a pending wait status for this thread, there is no
1920 point in resuming the process. But first make sure that
1921 linux_nat_wait won't preemptively handle the event - we
1922 should never take this short-circuit if we are going to
1923 leave LP running, since we have skipped resuming all the
1924 other threads. This bit of code needs to be synchronized
1925 with linux_nat_wait. */
1927 if (lp
->status
&& WIFSTOPPED (lp
->status
))
1930 && WSTOPSIG (lp
->status
)
1931 && sigismember (&pass_mask
, WSTOPSIG (lp
->status
)))
1933 if (debug_linux_nat
)
1934 fprintf_unfiltered (gdb_stdlog
,
1935 "LLR: Not short circuiting for ignored "
1936 "status 0x%x\n", lp
->status
);
1938 /* FIXME: What should we do if we are supposed to continue
1939 this thread with a signal? */
1940 gdb_assert (signo
== TARGET_SIGNAL_0
);
1941 signo
= target_signal_from_host (WSTOPSIG (lp
->status
));
1946 if (lp
->status
|| lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
1948 /* FIXME: What should we do if we are supposed to continue
1949 this thread with a signal? */
1950 gdb_assert (signo
== TARGET_SIGNAL_0
);
1952 if (debug_linux_nat
)
1953 fprintf_unfiltered (gdb_stdlog
,
1954 "LLR: Short circuiting for status 0x%x\n",
1957 restore_child_signals_mask (&prev_mask
);
1958 if (target_can_async_p ())
1960 target_async (inferior_event_handler
, 0);
1961 /* Tell the event loop we have something to process. */
1967 /* Mark LWP as not stopped to prevent it from being continued by
1972 iterate_over_lwps (ptid
, resume_callback
, NULL
);
1974 /* Convert to something the lower layer understands. */
1975 ptid
= pid_to_ptid (GET_LWP (lp
->ptid
));
1977 linux_ops
->to_resume (linux_ops
, ptid
, step
, signo
);
1978 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
1979 lp
->stopped_by_watchpoint
= 0;
1981 if (debug_linux_nat
)
1982 fprintf_unfiltered (gdb_stdlog
,
1983 "LLR: %s %s, %s (resume event thread)\n",
1984 step
? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
1985 target_pid_to_str (ptid
),
1986 (signo
!= TARGET_SIGNAL_0
1987 ? strsignal (target_signal_to_host (signo
)) : "0"));
1989 restore_child_signals_mask (&prev_mask
);
1990 if (target_can_async_p ())
1991 target_async (inferior_event_handler
, 0);
1994 /* Send a signal to an LWP. */
1997 kill_lwp (int lwpid
, int signo
)
1999 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2000 fails, then we are not using nptl threads and we should be using kill. */
2002 #ifdef HAVE_TKILL_SYSCALL
2004 static int tkill_failed
;
2011 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2012 if (errno
!= ENOSYS
)
2019 return kill (lwpid
, signo
);
2022 /* Handle a GNU/Linux syscall trap wait response. If we see a syscall
2023 event, check if the core is interested in it: if not, ignore the
2024 event, and keep waiting; otherwise, we need to toggle the LWP's
2025 syscall entry/exit status, since the ptrace event itself doesn't
2026 indicate it, and report the trap to higher layers. */
2029 linux_handle_syscall_trap (struct lwp_info
*lp
, int stopping
)
2031 struct target_waitstatus
*ourstatus
= &lp
->waitstatus
;
2032 struct gdbarch
*gdbarch
= target_thread_architecture (lp
->ptid
);
2033 int syscall_number
= (int) gdbarch_get_syscall_number (gdbarch
, lp
->ptid
);
2037 /* If we're stopping threads, there's a SIGSTOP pending, which
2038 makes it so that the LWP reports an immediate syscall return,
2039 followed by the SIGSTOP. Skip seeing that "return" using
2040 PTRACE_CONT directly, and let stop_wait_callback collect the
2041 SIGSTOP. Later when the thread is resumed, a new syscall
2042 entry event. If we didn't do this (and returned 0), we'd
2043 leave a syscall entry pending, and our caller, by using
2044 PTRACE_CONT to collect the SIGSTOP, skips the syscall return
2045 itself. Later, when the user re-resumes this LWP, we'd see
2046 another syscall entry event and we'd mistake it for a return.
2048 If stop_wait_callback didn't force the SIGSTOP out of the LWP
2049 (leaving immediately with LWP->signalled set, without issuing
2050 a PTRACE_CONT), it would still be problematic to leave this
2051 syscall enter pending, as later when the thread is resumed,
2052 it would then see the same syscall exit mentioned above,
2053 followed by the delayed SIGSTOP, while the syscall didn't
2054 actually get to execute. It seems it would be even more
2055 confusing to the user. */
2057 if (debug_linux_nat
)
2058 fprintf_unfiltered (gdb_stdlog
,
2059 "LHST: ignoring syscall %d "
2060 "for LWP %ld (stopping threads), "
2061 "resuming with PTRACE_CONT for SIGSTOP\n",
2063 GET_LWP (lp
->ptid
));
2065 lp
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2066 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2070 if (catch_syscall_enabled ())
2072 /* Always update the entry/return state, even if this particular
2073 syscall isn't interesting to the core now. In async mode,
2074 the user could install a new catchpoint for this syscall
2075 between syscall enter/return, and we'll need to know to
2076 report a syscall return if that happens. */
2077 lp
->syscall_state
= (lp
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2078 ? TARGET_WAITKIND_SYSCALL_RETURN
2079 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2081 if (catching_syscall_number (syscall_number
))
2083 /* Alright, an event to report. */
2084 ourstatus
->kind
= lp
->syscall_state
;
2085 ourstatus
->value
.syscall_number
= syscall_number
;
2087 if (debug_linux_nat
)
2088 fprintf_unfiltered (gdb_stdlog
,
2089 "LHST: stopping for %s of syscall %d"
2092 == TARGET_WAITKIND_SYSCALL_ENTRY
2093 ? "entry" : "return",
2095 GET_LWP (lp
->ptid
));
2099 if (debug_linux_nat
)
2100 fprintf_unfiltered (gdb_stdlog
,
2101 "LHST: ignoring %s of syscall %d "
2103 lp
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2104 ? "entry" : "return",
2106 GET_LWP (lp
->ptid
));
2110 /* If we had been syscall tracing, and hence used PT_SYSCALL
2111 before on this LWP, it could happen that the user removes all
2112 syscall catchpoints before we get to process this event.
2113 There are two noteworthy issues here:
2115 - When stopped at a syscall entry event, resuming with
2116 PT_STEP still resumes executing the syscall and reports a
2119 - Only PT_SYSCALL catches syscall enters. If we last
2120 single-stepped this thread, then this event can't be a
2121 syscall enter. If we last single-stepped this thread, this
2122 has to be a syscall exit.
2124 The points above mean that the next resume, be it PT_STEP or
2125 PT_CONTINUE, can not trigger a syscall trace event. */
2126 if (debug_linux_nat
)
2127 fprintf_unfiltered (gdb_stdlog
,
2128 "LHST: caught syscall event "
2129 "with no syscall catchpoints."
2130 " %d for LWP %ld, ignoring\n",
2132 GET_LWP (lp
->ptid
));
2133 lp
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2136 /* The core isn't interested in this event. For efficiency, avoid
2137 stopping all threads only to have the core resume them all again.
2138 Since we're not stopping threads, if we're still syscall tracing
2139 and not stepping, we can't use PTRACE_CONT here, as we'd miss any
2140 subsequent syscall. Simply resume using the inf-ptrace layer,
2141 which knows when to use PT_SYSCALL or PT_CONTINUE. */
2143 /* Note that gdbarch_get_syscall_number may access registers, hence
2145 registers_changed ();
2146 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
2147 lp
->step
, TARGET_SIGNAL_0
);
2151 /* Handle a GNU/Linux extended wait response. If we see a clone
2152 event, we need to add the new LWP to our list (and not report the
2153 trap to higher layers). This function returns non-zero if the
2154 event should be ignored and we should wait again. If STOPPING is
2155 true, the new LWP remains stopped, otherwise it is continued. */
2158 linux_handle_extended_wait (struct lwp_info
*lp
, int status
,
2161 int pid
= GET_LWP (lp
->ptid
);
2162 struct target_waitstatus
*ourstatus
= &lp
->waitstatus
;
2163 int event
= status
>> 16;
2165 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
2166 || event
== PTRACE_EVENT_CLONE
)
2168 unsigned long new_pid
;
2171 ptrace (PTRACE_GETEVENTMSG
, pid
, 0, &new_pid
);
2173 /* If we haven't already seen the new PID stop, wait for it now. */
2174 if (! pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
2176 /* The new child has a pending SIGSTOP. We can't affect it until it
2177 hits the SIGSTOP, but we're already attached. */
2178 ret
= my_waitpid (new_pid
, &status
,
2179 (event
== PTRACE_EVENT_CLONE
) ? __WCLONE
: 0);
2181 perror_with_name (_("waiting for new child"));
2182 else if (ret
!= new_pid
)
2183 internal_error (__FILE__
, __LINE__
,
2184 _("wait returned unexpected PID %d"), ret
);
2185 else if (!WIFSTOPPED (status
))
2186 internal_error (__FILE__
, __LINE__
,
2187 _("wait returned unexpected status 0x%x"), status
);
2190 ourstatus
->value
.related_pid
= ptid_build (new_pid
, new_pid
, 0);
2192 if (event
== PTRACE_EVENT_FORK
2193 && linux_fork_checkpointing_p (GET_PID (lp
->ptid
)))
2195 /* Handle checkpointing by linux-fork.c here as a special
2196 case. We don't want the follow-fork-mode or 'catch fork'
2197 to interfere with this. */
2199 /* This won't actually modify the breakpoint list, but will
2200 physically remove the breakpoints from the child. */
2201 detach_breakpoints (new_pid
);
2203 /* Retain child fork in ptrace (stopped) state. */
2204 if (!find_fork_pid (new_pid
))
2207 /* Report as spurious, so that infrun doesn't want to follow
2208 this fork. We're actually doing an infcall in
2210 ourstatus
->kind
= TARGET_WAITKIND_SPURIOUS
;
2211 linux_enable_event_reporting (pid_to_ptid (new_pid
));
2213 /* Report the stop to the core. */
2217 if (event
== PTRACE_EVENT_FORK
)
2218 ourstatus
->kind
= TARGET_WAITKIND_FORKED
;
2219 else if (event
== PTRACE_EVENT_VFORK
)
2220 ourstatus
->kind
= TARGET_WAITKIND_VFORKED
;
2223 struct lwp_info
*new_lp
;
2225 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2227 new_lp
= add_lwp (BUILD_LWP (new_pid
, GET_PID (lp
->ptid
)));
2229 new_lp
->stopped
= 1;
2231 if (WSTOPSIG (status
) != SIGSTOP
)
2233 /* This can happen if someone starts sending signals to
2234 the new thread before it gets a chance to run, which
2235 have a lower number than SIGSTOP (e.g. SIGUSR1).
2236 This is an unlikely case, and harder to handle for
2237 fork / vfork than for clone, so we do not try - but
2238 we handle it for clone events here. We'll send
2239 the other signal on to the thread below. */
2241 new_lp
->signalled
= 1;
2248 /* Add the new thread to GDB's lists as soon as possible
2251 1) the frontend doesn't have to wait for a stop to
2254 2) we tag it with the correct running state. */
2256 /* If the thread_db layer is active, let it know about
2257 this new thread, and add it to GDB's list. */
2258 if (!thread_db_attach_lwp (new_lp
->ptid
))
2260 /* We're not using thread_db. Add it to GDB's
2262 target_post_attach (GET_LWP (new_lp
->ptid
));
2263 add_thread (new_lp
->ptid
);
2268 set_running (new_lp
->ptid
, 1);
2269 set_executing (new_lp
->ptid
, 1);
2273 /* Note the need to use the low target ops to resume, to
2274 handle resuming with PT_SYSCALL if we have syscall
2278 enum target_signal signo
;
2280 new_lp
->stopped
= 0;
2281 new_lp
->resumed
= 1;
2282 new_lp
->last_resume_kind
= resume_continue
;
2285 ? target_signal_from_host (WSTOPSIG (status
))
2288 linux_ops
->to_resume (linux_ops
, pid_to_ptid (new_pid
),
2295 /* We created NEW_LP so it cannot yet contain STATUS. */
2296 gdb_assert (new_lp
->status
== 0);
2298 /* Save the wait status to report later. */
2299 if (debug_linux_nat
)
2300 fprintf_unfiltered (gdb_stdlog
,
2301 "LHEW: waitpid of new LWP %ld, "
2302 "saving status %s\n",
2303 (long) GET_LWP (new_lp
->ptid
),
2304 status_to_str (status
));
2305 new_lp
->status
= status
;
2309 if (debug_linux_nat
)
2310 fprintf_unfiltered (gdb_stdlog
,
2311 "LHEW: Got clone event "
2312 "from LWP %ld, resuming\n",
2313 GET_LWP (lp
->ptid
));
2314 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
2315 0, TARGET_SIGNAL_0
);
2323 if (event
== PTRACE_EVENT_EXEC
)
2325 if (debug_linux_nat
)
2326 fprintf_unfiltered (gdb_stdlog
,
2327 "LHEW: Got exec event from LWP %ld\n",
2328 GET_LWP (lp
->ptid
));
2330 ourstatus
->kind
= TARGET_WAITKIND_EXECD
;
2331 ourstatus
->value
.execd_pathname
2332 = xstrdup (linux_child_pid_to_exec_file (pid
));
2337 if (event
== PTRACE_EVENT_VFORK_DONE
)
2339 if (current_inferior ()->waiting_for_vfork_done
)
2341 if (debug_linux_nat
)
2342 fprintf_unfiltered (gdb_stdlog
,
2343 "LHEW: Got expected PTRACE_EVENT_"
2344 "VFORK_DONE from LWP %ld: stopping\n",
2345 GET_LWP (lp
->ptid
));
2347 ourstatus
->kind
= TARGET_WAITKIND_VFORK_DONE
;
2351 if (debug_linux_nat
)
2352 fprintf_unfiltered (gdb_stdlog
,
2353 "LHEW: Got PTRACE_EVENT_VFORK_DONE "
2354 "from LWP %ld: resuming\n",
2355 GET_LWP (lp
->ptid
));
2356 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2360 internal_error (__FILE__
, __LINE__
,
2361 _("unknown ptrace event %d"), event
);
2364 /* Return non-zero if LWP is a zombie. */
2367 linux_lwp_is_zombie (long lwp
)
2369 char buffer
[MAXPATHLEN
];
2373 xsnprintf (buffer
, sizeof (buffer
), "/proc/%ld/status", lwp
);
2374 procfile
= fopen (buffer
, "r");
2375 if (procfile
== NULL
)
2377 warning (_("unable to open /proc file '%s'"), buffer
);
2380 while (fgets (buffer
, sizeof (buffer
), procfile
) != NULL
)
2381 if (strcmp (buffer
, "State:\tZ (zombie)\n") == 0)
2391 /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has
2395 wait_lwp (struct lwp_info
*lp
)
2399 int thread_dead
= 0;
2402 gdb_assert (!lp
->stopped
);
2403 gdb_assert (lp
->status
== 0);
2405 /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */
2406 block_child_signals (&prev_mask
);
2410 /* If my_waitpid returns 0 it means the __WCLONE vs. non-__WCLONE kind
2411 was right and we should just call sigsuspend. */
2413 pid
= my_waitpid (GET_LWP (lp
->ptid
), &status
, WNOHANG
);
2414 if (pid
== -1 && errno
== ECHILD
)
2415 pid
= my_waitpid (GET_LWP (lp
->ptid
), &status
, __WCLONE
| WNOHANG
);
2416 if (pid
== -1 && errno
== ECHILD
)
2418 /* The thread has previously exited. We need to delete it
2419 now because, for some vendor 2.4 kernels with NPTL
2420 support backported, there won't be an exit event unless
2421 it is the main thread. 2.6 kernels will report an exit
2422 event for each thread that exits, as expected. */
2424 if (debug_linux_nat
)
2425 fprintf_unfiltered (gdb_stdlog
, "WL: %s vanished.\n",
2426 target_pid_to_str (lp
->ptid
));
2431 /* Bugs 10970, 12702.
2432 Thread group leader may have exited in which case we'll lock up in
2433 waitpid if there are other threads, even if they are all zombies too.
2434 Basically, we're not supposed to use waitpid this way.
2435 __WCLONE is not applicable for the leader so we can't use that.
2436 LINUX_NAT_THREAD_ALIVE cannot be used here as it requires a STOPPED
2437 process; it gets ESRCH both for the zombie and for running processes.
2439 As a workaround, check if we're waiting for the thread group leader and
2440 if it's a zombie, and avoid calling waitpid if it is.
2442 This is racy, what if the tgl becomes a zombie right after we check?
2443 Therefore always use WNOHANG with sigsuspend - it is equivalent to
2444 waiting waitpid but the linux_lwp_is_zombie is safe this way. */
2446 if (GET_PID (lp
->ptid
) == GET_LWP (lp
->ptid
)
2447 && linux_lwp_is_zombie (GET_LWP (lp
->ptid
)))
2450 if (debug_linux_nat
)
2451 fprintf_unfiltered (gdb_stdlog
,
2452 "WL: Thread group leader %s vanished.\n",
2453 target_pid_to_str (lp
->ptid
));
2457 /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers
2458 get invoked despite our caller had them intentionally blocked by
2459 block_child_signals. This is sensitive only to the loop of
2460 linux_nat_wait_1 and there if we get called my_waitpid gets called
2461 again before it gets to sigsuspend so we can safely let the handlers
2462 get executed here. */
2464 sigsuspend (&suspend_mask
);
2467 restore_child_signals_mask (&prev_mask
);
2471 gdb_assert (pid
== GET_LWP (lp
->ptid
));
2473 if (debug_linux_nat
)
2475 fprintf_unfiltered (gdb_stdlog
,
2476 "WL: waitpid %s received %s\n",
2477 target_pid_to_str (lp
->ptid
),
2478 status_to_str (status
));
2481 /* Check if the thread has exited. */
2482 if (WIFEXITED (status
) || WIFSIGNALED (status
))
2485 if (debug_linux_nat
)
2486 fprintf_unfiltered (gdb_stdlog
, "WL: %s exited.\n",
2487 target_pid_to_str (lp
->ptid
));
2497 gdb_assert (WIFSTOPPED (status
));
2499 /* Handle GNU/Linux's syscall SIGTRAPs. */
2500 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SYSCALL_SIGTRAP
)
2502 /* No longer need the sysgood bit. The ptrace event ends up
2503 recorded in lp->waitstatus if we care for it. We can carry
2504 on handling the event like a regular SIGTRAP from here
2506 status
= W_STOPCODE (SIGTRAP
);
2507 if (linux_handle_syscall_trap (lp
, 1))
2508 return wait_lwp (lp
);
2511 /* Handle GNU/Linux's extended waitstatus for trace events. */
2512 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
2514 if (debug_linux_nat
)
2515 fprintf_unfiltered (gdb_stdlog
,
2516 "WL: Handling extended status 0x%06x\n",
2518 if (linux_handle_extended_wait (lp
, status
, 1))
2519 return wait_lwp (lp
);
2525 /* Save the most recent siginfo for LP. This is currently only called
2526 for SIGTRAP; some ports use the si_addr field for
2527 target_stopped_data_address. In the future, it may also be used to
2528 restore the siginfo of requeued signals. */
2531 save_siginfo (struct lwp_info
*lp
)
2534 ptrace (PTRACE_GETSIGINFO
, GET_LWP (lp
->ptid
),
2535 (PTRACE_TYPE_ARG3
) 0, &lp
->siginfo
);
2538 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
2541 /* Send a SIGSTOP to LP. */
2544 stop_callback (struct lwp_info
*lp
, void *data
)
2546 if (!lp
->stopped
&& !lp
->signalled
)
2550 if (debug_linux_nat
)
2552 fprintf_unfiltered (gdb_stdlog
,
2553 "SC: kill %s **<SIGSTOP>**\n",
2554 target_pid_to_str (lp
->ptid
));
2557 ret
= kill_lwp (GET_LWP (lp
->ptid
), SIGSTOP
);
2558 if (debug_linux_nat
)
2560 fprintf_unfiltered (gdb_stdlog
,
2561 "SC: lwp kill %d %s\n",
2563 errno
? safe_strerror (errno
) : "ERRNO-OK");
2567 gdb_assert (lp
->status
== 0);
2573 /* Return non-zero if LWP PID has a pending SIGINT. */
2576 linux_nat_has_pending_sigint (int pid
)
2578 sigset_t pending
, blocked
, ignored
;
2580 linux_proc_pending_signals (pid
, &pending
, &blocked
, &ignored
);
2582 if (sigismember (&pending
, SIGINT
)
2583 && !sigismember (&ignored
, SIGINT
))
2589 /* Set a flag in LP indicating that we should ignore its next SIGINT. */
2592 set_ignore_sigint (struct lwp_info
*lp
, void *data
)
2594 /* If a thread has a pending SIGINT, consume it; otherwise, set a
2595 flag to consume the next one. */
2596 if (lp
->stopped
&& lp
->status
!= 0 && WIFSTOPPED (lp
->status
)
2597 && WSTOPSIG (lp
->status
) == SIGINT
)
2600 lp
->ignore_sigint
= 1;
2605 /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag.
2606 This function is called after we know the LWP has stopped; if the LWP
2607 stopped before the expected SIGINT was delivered, then it will never have
2608 arrived. Also, if the signal was delivered to a shared queue and consumed
2609 by a different thread, it will never be delivered to this LWP. */
2612 maybe_clear_ignore_sigint (struct lwp_info
*lp
)
2614 if (!lp
->ignore_sigint
)
2617 if (!linux_nat_has_pending_sigint (GET_LWP (lp
->ptid
)))
2619 if (debug_linux_nat
)
2620 fprintf_unfiltered (gdb_stdlog
,
2621 "MCIS: Clearing bogus flag for %s\n",
2622 target_pid_to_str (lp
->ptid
));
2623 lp
->ignore_sigint
= 0;
2627 /* Fetch the possible triggered data watchpoint info and store it in
2630 On some archs, like x86, that use debug registers to set
2631 watchpoints, it's possible that the way to know which watched
2632 address trapped, is to check the register that is used to select
2633 which address to watch. Problem is, between setting the watchpoint
2634 and reading back which data address trapped, the user may change
2635 the set of watchpoints, and, as a consequence, GDB changes the
2636 debug registers in the inferior. To avoid reading back a stale
2637 stopped-data-address when that happens, we cache in LP the fact
2638 that a watchpoint trapped, and the corresponding data address, as
2639 soon as we see LP stop with a SIGTRAP. If GDB changes the debug
2640 registers meanwhile, we have the cached data we can rely on. */
2643 save_sigtrap (struct lwp_info
*lp
)
2645 struct cleanup
*old_chain
;
2647 if (linux_ops
->to_stopped_by_watchpoint
== NULL
)
2649 lp
->stopped_by_watchpoint
= 0;
2653 old_chain
= save_inferior_ptid ();
2654 inferior_ptid
= lp
->ptid
;
2656 lp
->stopped_by_watchpoint
= linux_ops
->to_stopped_by_watchpoint ();
2658 if (lp
->stopped_by_watchpoint
)
2660 if (linux_ops
->to_stopped_data_address
!= NULL
)
2661 lp
->stopped_data_address_p
=
2662 linux_ops
->to_stopped_data_address (¤t_target
,
2663 &lp
->stopped_data_address
);
2665 lp
->stopped_data_address_p
= 0;
2668 do_cleanups (old_chain
);
2671 /* See save_sigtrap. */
2674 linux_nat_stopped_by_watchpoint (void)
2676 struct lwp_info
*lp
= find_lwp_pid (inferior_ptid
);
2678 gdb_assert (lp
!= NULL
);
2680 return lp
->stopped_by_watchpoint
;
2684 linux_nat_stopped_data_address (struct target_ops
*ops
, CORE_ADDR
*addr_p
)
2686 struct lwp_info
*lp
= find_lwp_pid (inferior_ptid
);
2688 gdb_assert (lp
!= NULL
);
2690 *addr_p
= lp
->stopped_data_address
;
2692 return lp
->stopped_data_address_p
;
2695 /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */
2698 sigtrap_is_event (int status
)
2700 return WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
;
2703 /* SIGTRAP-like events recognizer. */
2705 static int (*linux_nat_status_is_event
) (int status
) = sigtrap_is_event
;
2707 /* Check for SIGTRAP-like events in LP. */
2710 linux_nat_lp_status_is_event (struct lwp_info
*lp
)
2712 /* We check for lp->waitstatus in addition to lp->status, because we can
2713 have pending process exits recorded in lp->status
2714 and W_EXITCODE(0,0) == 0. We should probably have an additional
2715 lp->status_p flag. */
2717 return (lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
2718 && linux_nat_status_is_event (lp
->status
));
2721 /* Set alternative SIGTRAP-like events recognizer. If
2722 breakpoint_inserted_here_p there then gdbarch_decr_pc_after_break will be
2726 linux_nat_set_status_is_event (struct target_ops
*t
,
2727 int (*status_is_event
) (int status
))
2729 linux_nat_status_is_event
= status_is_event
;
2732 /* Wait until LP is stopped. */
2735 stop_wait_callback (struct lwp_info
*lp
, void *data
)
2737 struct inferior
*inf
= find_inferior_pid (GET_PID (lp
->ptid
));
2739 /* If this is a vfork parent, bail out, it is not going to report
2740 any SIGSTOP until the vfork is done with. */
2741 if (inf
->vfork_child
!= NULL
)
2748 status
= wait_lwp (lp
);
2752 if (lp
->ignore_sigint
&& WIFSTOPPED (status
)
2753 && WSTOPSIG (status
) == SIGINT
)
2755 lp
->ignore_sigint
= 0;
2758 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2759 if (debug_linux_nat
)
2760 fprintf_unfiltered (gdb_stdlog
,
2761 "PTRACE_CONT %s, 0, 0 (%s) "
2762 "(discarding SIGINT)\n",
2763 target_pid_to_str (lp
->ptid
),
2764 errno
? safe_strerror (errno
) : "OK");
2766 return stop_wait_callback (lp
, NULL
);
2769 maybe_clear_ignore_sigint (lp
);
2771 if (WSTOPSIG (status
) != SIGSTOP
)
2773 if (linux_nat_status_is_event (status
))
2775 /* If a LWP other than the LWP that we're reporting an
2776 event for has hit a GDB breakpoint (as opposed to
2777 some random trap signal), then just arrange for it to
2778 hit it again later. We don't keep the SIGTRAP status
2779 and don't forward the SIGTRAP signal to the LWP. We
2780 will handle the current event, eventually we will
2781 resume all LWPs, and this one will get its breakpoint
2784 If we do not do this, then we run the risk that the
2785 user will delete or disable the breakpoint, but the
2786 thread will have already tripped on it. */
2788 /* Save the trap's siginfo in case we need it later. */
2793 /* Now resume this LWP and get the SIGSTOP event. */
2795 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2796 if (debug_linux_nat
)
2798 fprintf_unfiltered (gdb_stdlog
,
2799 "PTRACE_CONT %s, 0, 0 (%s)\n",
2800 target_pid_to_str (lp
->ptid
),
2801 errno
? safe_strerror (errno
) : "OK");
2803 fprintf_unfiltered (gdb_stdlog
,
2804 "SWC: Candidate SIGTRAP event in %s\n",
2805 target_pid_to_str (lp
->ptid
));
2807 /* Hold this event/waitstatus while we check to see if
2808 there are any more (we still want to get that SIGSTOP). */
2809 stop_wait_callback (lp
, NULL
);
2811 /* Hold the SIGTRAP for handling by linux_nat_wait. If
2812 there's another event, throw it back into the
2816 if (debug_linux_nat
)
2817 fprintf_unfiltered (gdb_stdlog
,
2818 "SWC: kill %s, %s\n",
2819 target_pid_to_str (lp
->ptid
),
2820 status_to_str ((int) status
));
2821 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (lp
->status
));
2824 /* Save the sigtrap event. */
2825 lp
->status
= status
;
2830 /* The thread was stopped with a signal other than
2831 SIGSTOP, and didn't accidentally trip a breakpoint. */
2833 if (debug_linux_nat
)
2835 fprintf_unfiltered (gdb_stdlog
,
2836 "SWC: Pending event %s in %s\n",
2837 status_to_str ((int) status
),
2838 target_pid_to_str (lp
->ptid
));
2840 /* Now resume this LWP and get the SIGSTOP event. */
2842 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2843 if (debug_linux_nat
)
2844 fprintf_unfiltered (gdb_stdlog
,
2845 "SWC: PTRACE_CONT %s, 0, 0 (%s)\n",
2846 target_pid_to_str (lp
->ptid
),
2847 errno
? safe_strerror (errno
) : "OK");
2849 /* Hold this event/waitstatus while we check to see if
2850 there are any more (we still want to get that SIGSTOP). */
2851 stop_wait_callback (lp
, NULL
);
2853 /* If the lp->status field is still empty, use it to
2854 hold this event. If not, then this event must be
2855 returned to the event queue of the LWP. */
2858 if (debug_linux_nat
)
2860 fprintf_unfiltered (gdb_stdlog
,
2861 "SWC: kill %s, %s\n",
2862 target_pid_to_str (lp
->ptid
),
2863 status_to_str ((int) status
));
2865 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (status
));
2868 lp
->status
= status
;
2874 /* We caught the SIGSTOP that we intended to catch, so
2875 there's no SIGSTOP pending. */
2884 /* Return non-zero if LP has a wait status pending. */
2887 status_callback (struct lwp_info
*lp
, void *data
)
2889 /* Only report a pending wait status if we pretend that this has
2890 indeed been resumed. */
2894 if (lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
2896 /* A ptrace event, like PTRACE_FORK|VFORK|EXEC, syscall event,
2897 or a pending process exit. Note that `W_EXITCODE(0,0) ==
2898 0', so a clean process exit can not be stored pending in
2899 lp->status, it is indistinguishable from
2900 no-pending-status. */
2904 if (lp
->status
!= 0)
2910 /* Return non-zero if LP isn't stopped. */
2913 running_callback (struct lwp_info
*lp
, void *data
)
2915 return (!lp
->stopped
2916 || ((lp
->status
!= 0
2917 || lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
2921 /* Count the LWP's that have had events. */
2924 count_events_callback (struct lwp_info
*lp
, void *data
)
2928 gdb_assert (count
!= NULL
);
2930 /* Count only resumed LWPs that have a SIGTRAP event pending. */
2931 if (lp
->resumed
&& linux_nat_lp_status_is_event (lp
))
2937 /* Select the LWP (if any) that is currently being single-stepped. */
2940 select_singlestep_lwp_callback (struct lwp_info
*lp
, void *data
)
2942 if (lp
->last_resume_kind
== resume_step
2949 /* Select the Nth LWP that has had a SIGTRAP event. */
2952 select_event_lwp_callback (struct lwp_info
*lp
, void *data
)
2954 int *selector
= data
;
2956 gdb_assert (selector
!= NULL
);
2958 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2959 if (lp
->resumed
&& linux_nat_lp_status_is_event (lp
))
2960 if ((*selector
)-- == 0)
2967 cancel_breakpoint (struct lwp_info
*lp
)
2969 /* Arrange for a breakpoint to be hit again later. We don't keep
2970 the SIGTRAP status and don't forward the SIGTRAP signal to the
2971 LWP. We will handle the current event, eventually we will resume
2972 this LWP, and this breakpoint will trap again.
2974 If we do not do this, then we run the risk that the user will
2975 delete or disable the breakpoint, but the LWP will have already
2978 struct regcache
*regcache
= get_thread_regcache (lp
->ptid
);
2979 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2982 pc
= regcache_read_pc (regcache
) - gdbarch_decr_pc_after_break (gdbarch
);
2983 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
2985 if (debug_linux_nat
)
2986 fprintf_unfiltered (gdb_stdlog
,
2987 "CB: Push back breakpoint for %s\n",
2988 target_pid_to_str (lp
->ptid
));
2990 /* Back up the PC if necessary. */
2991 if (gdbarch_decr_pc_after_break (gdbarch
))
2992 regcache_write_pc (regcache
, pc
);
3000 cancel_breakpoints_callback (struct lwp_info
*lp
, void *data
)
3002 struct lwp_info
*event_lp
= data
;
3004 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
3008 /* If a LWP other than the LWP that we're reporting an event for has
3009 hit a GDB breakpoint (as opposed to some random trap signal),
3010 then just arrange for it to hit it again later. We don't keep
3011 the SIGTRAP status and don't forward the SIGTRAP signal to the
3012 LWP. We will handle the current event, eventually we will resume
3013 all LWPs, and this one will get its breakpoint trap again.
3015 If we do not do this, then we run the risk that the user will
3016 delete or disable the breakpoint, but the LWP will have already
3019 if (linux_nat_lp_status_is_event (lp
)
3020 && cancel_breakpoint (lp
))
3021 /* Throw away the SIGTRAP. */
3027 /* Select one LWP out of those that have events pending. */
3030 select_event_lwp (ptid_t filter
, struct lwp_info
**orig_lp
, int *status
)
3033 int random_selector
;
3034 struct lwp_info
*event_lp
;
3036 /* Record the wait status for the original LWP. */
3037 (*orig_lp
)->status
= *status
;
3039 /* Give preference to any LWP that is being single-stepped. */
3040 event_lp
= iterate_over_lwps (filter
,
3041 select_singlestep_lwp_callback
, NULL
);
3042 if (event_lp
!= NULL
)
3044 if (debug_linux_nat
)
3045 fprintf_unfiltered (gdb_stdlog
,
3046 "SEL: Select single-step %s\n",
3047 target_pid_to_str (event_lp
->ptid
));
3051 /* No single-stepping LWP. Select one at random, out of those
3052 which have had SIGTRAP events. */
3054 /* First see how many SIGTRAP events we have. */
3055 iterate_over_lwps (filter
, count_events_callback
, &num_events
);
3057 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
3058 random_selector
= (int)
3059 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3061 if (debug_linux_nat
&& num_events
> 1)
3062 fprintf_unfiltered (gdb_stdlog
,
3063 "SEL: Found %d SIGTRAP events, selecting #%d\n",
3064 num_events
, random_selector
);
3066 event_lp
= iterate_over_lwps (filter
,
3067 select_event_lwp_callback
,
3071 if (event_lp
!= NULL
)
3073 /* Switch the event LWP. */
3074 *orig_lp
= event_lp
;
3075 *status
= event_lp
->status
;
3078 /* Flush the wait status for the event LWP. */
3079 (*orig_lp
)->status
= 0;
3082 /* Return non-zero if LP has been resumed. */
3085 resumed_callback (struct lwp_info
*lp
, void *data
)
3090 /* Stop an active thread, verify it still exists, then resume it. */
3093 stop_and_resume_callback (struct lwp_info
*lp
, void *data
)
3097 enum resume_kind last_resume_kind
= lp
->last_resume_kind
;
3098 ptid_t ptid
= lp
->ptid
;
3100 stop_callback (lp
, NULL
);
3101 stop_wait_callback (lp
, NULL
);
3103 /* Resume if the lwp still exists, and the core wanted it
3105 if (last_resume_kind
!= resume_stop
)
3107 lp
= find_lwp_pid (ptid
);
3109 resume_lwp (lp
, lp
->step
);
3115 /* Check if we should go on and pass this event to common code.
3116 Return the affected lwp if we are, or NULL otherwise. */
3117 static struct lwp_info
*
3118 linux_nat_filter_event (int lwpid
, int status
, int options
)
3120 struct lwp_info
*lp
;
3122 lp
= find_lwp_pid (pid_to_ptid (lwpid
));
3124 /* Check for stop events reported by a process we didn't already
3125 know about - anything not already in our LWP list.
3127 If we're expecting to receive stopped processes after
3128 fork, vfork, and clone events, then we'll just add the
3129 new one to our list and go back to waiting for the event
3130 to be reported - the stopped process might be returned
3131 from waitpid before or after the event is. */
3132 if (WIFSTOPPED (status
) && !lp
)
3134 add_to_pid_list (&stopped_pids
, lwpid
, status
);
3138 /* Make sure we don't report an event for the exit of an LWP not in
3139 our list, i.e. not part of the current process. This can happen
3140 if we detach from a program we originally forked and then it
3142 if (!WIFSTOPPED (status
) && !lp
)
3145 /* NOTE drow/2003-06-17: This code seems to be meant for debugging
3146 CLONE_PTRACE processes which do not use the thread library -
3147 otherwise we wouldn't find the new LWP this way. That doesn't
3148 currently work, and the following code is currently unreachable
3149 due to the two blocks above. If it's fixed some day, this code
3150 should be broken out into a function so that we can also pick up
3151 LWPs from the new interface. */
3154 lp
= add_lwp (BUILD_LWP (lwpid
, GET_PID (inferior_ptid
)));
3155 if (options
& __WCLONE
)
3158 gdb_assert (WIFSTOPPED (status
)
3159 && WSTOPSIG (status
) == SIGSTOP
);
3162 if (!in_thread_list (inferior_ptid
))
3164 inferior_ptid
= BUILD_LWP (GET_PID (inferior_ptid
),
3165 GET_PID (inferior_ptid
));
3166 add_thread (inferior_ptid
);
3169 add_thread (lp
->ptid
);
3172 /* Handle GNU/Linux's syscall SIGTRAPs. */
3173 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SYSCALL_SIGTRAP
)
3175 /* No longer need the sysgood bit. The ptrace event ends up
3176 recorded in lp->waitstatus if we care for it. We can carry
3177 on handling the event like a regular SIGTRAP from here
3179 status
= W_STOPCODE (SIGTRAP
);
3180 if (linux_handle_syscall_trap (lp
, 0))
3184 /* Handle GNU/Linux's extended waitstatus for trace events. */
3185 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
3187 if (debug_linux_nat
)
3188 fprintf_unfiltered (gdb_stdlog
,
3189 "LLW: Handling extended status 0x%06x\n",
3191 if (linux_handle_extended_wait (lp
, status
, 0))
3195 if (linux_nat_status_is_event (status
))
3197 /* Save the trap's siginfo in case we need it later. */
3203 /* Check if the thread has exited. */
3204 if ((WIFEXITED (status
) || WIFSIGNALED (status
))
3205 && num_lwps (GET_PID (lp
->ptid
)) > 1)
3207 /* If this is the main thread, we must stop all threads and verify
3208 if they are still alive. This is because in the nptl thread model
3209 on Linux 2.4, there is no signal issued for exiting LWPs
3210 other than the main thread. We only get the main thread exit
3211 signal once all child threads have already exited. If we
3212 stop all the threads and use the stop_wait_callback to check
3213 if they have exited we can determine whether this signal
3214 should be ignored or whether it means the end of the debugged
3215 application, regardless of which threading model is being
3217 if (GET_PID (lp
->ptid
) == GET_LWP (lp
->ptid
))
3220 iterate_over_lwps (pid_to_ptid (GET_PID (lp
->ptid
)),
3221 stop_and_resume_callback
, NULL
);
3224 if (debug_linux_nat
)
3225 fprintf_unfiltered (gdb_stdlog
,
3226 "LLW: %s exited.\n",
3227 target_pid_to_str (lp
->ptid
));
3229 if (num_lwps (GET_PID (lp
->ptid
)) > 1)
3231 /* If there is at least one more LWP, then the exit signal
3232 was not the end of the debugged application and should be
3239 /* Check if the current LWP has previously exited. In the nptl
3240 thread model, LWPs other than the main thread do not issue
3241 signals when they exit so we must check whenever the thread has
3242 stopped. A similar check is made in stop_wait_callback(). */
3243 if (num_lwps (GET_PID (lp
->ptid
)) > 1 && !linux_thread_alive (lp
->ptid
))
3245 ptid_t ptid
= pid_to_ptid (GET_PID (lp
->ptid
));
3247 if (debug_linux_nat
)
3248 fprintf_unfiltered (gdb_stdlog
,
3249 "LLW: %s exited.\n",
3250 target_pid_to_str (lp
->ptid
));
3254 /* Make sure there is at least one thread running. */
3255 gdb_assert (iterate_over_lwps (ptid
, running_callback
, NULL
));
3257 /* Discard the event. */
3261 /* Make sure we don't report a SIGSTOP that we sent ourselves in
3262 an attempt to stop an LWP. */
3264 && WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGSTOP
)
3266 if (debug_linux_nat
)
3267 fprintf_unfiltered (gdb_stdlog
,
3268 "LLW: Delayed SIGSTOP caught for %s.\n",
3269 target_pid_to_str (lp
->ptid
));
3273 if (lp
->last_resume_kind
!= resume_stop
)
3275 /* This is a delayed SIGSTOP. */
3277 registers_changed ();
3279 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3280 lp
->step
, TARGET_SIGNAL_0
);
3281 if (debug_linux_nat
)
3282 fprintf_unfiltered (gdb_stdlog
,
3283 "LLW: %s %s, 0, 0 (discard SIGSTOP)\n",
3285 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3286 target_pid_to_str (lp
->ptid
));
3289 gdb_assert (lp
->resumed
);
3291 /* Discard the event. */
3296 /* Make sure we don't report a SIGINT that we have already displayed
3297 for another thread. */
3298 if (lp
->ignore_sigint
3299 && WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGINT
)
3301 if (debug_linux_nat
)
3302 fprintf_unfiltered (gdb_stdlog
,
3303 "LLW: Delayed SIGINT caught for %s.\n",
3304 target_pid_to_str (lp
->ptid
));
3306 /* This is a delayed SIGINT. */
3307 lp
->ignore_sigint
= 0;
3309 registers_changed ();
3310 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3311 lp
->step
, TARGET_SIGNAL_0
);
3312 if (debug_linux_nat
)
3313 fprintf_unfiltered (gdb_stdlog
,
3314 "LLW: %s %s, 0, 0 (discard SIGINT)\n",
3316 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3317 target_pid_to_str (lp
->ptid
));
3320 gdb_assert (lp
->resumed
);
3322 /* Discard the event. */
3326 /* An interesting event. */
3328 lp
->status
= status
;
3333 linux_nat_wait_1 (struct target_ops
*ops
,
3334 ptid_t ptid
, struct target_waitstatus
*ourstatus
,
3337 static sigset_t prev_mask
;
3338 struct lwp_info
*lp
= NULL
;
3343 if (debug_linux_nat
)
3344 fprintf_unfiltered (gdb_stdlog
, "LLW: enter\n");
3346 /* The first time we get here after starting a new inferior, we may
3347 not have added it to the LWP list yet - this is the earliest
3348 moment at which we know its PID. */
3349 if (ptid_is_pid (inferior_ptid
))
3351 /* Upgrade the main thread's ptid. */
3352 thread_change_ptid (inferior_ptid
,
3353 BUILD_LWP (GET_PID (inferior_ptid
),
3354 GET_PID (inferior_ptid
)));
3356 lp
= add_lwp (inferior_ptid
);
3360 /* Make sure SIGCHLD is blocked. */
3361 block_child_signals (&prev_mask
);
3363 if (ptid_equal (ptid
, minus_one_ptid
))
3365 else if (ptid_is_pid (ptid
))
3366 /* A request to wait for a specific tgid. This is not possible
3367 with waitpid, so instead, we wait for any child, and leave
3368 children we're not interested in right now with a pending
3369 status to report later. */
3372 pid
= GET_LWP (ptid
);
3378 /* Make sure that of those LWPs we want to get an event from, there
3379 is at least one LWP that has been resumed. If there's none, just
3380 bail out. The core may just be flushing asynchronously all
3382 if (iterate_over_lwps (ptid
, resumed_callback
, NULL
) == NULL
)
3384 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3386 if (debug_linux_nat
)
3387 fprintf_unfiltered (gdb_stdlog
, "LLW: exit (no resumed LWP)\n");
3389 restore_child_signals_mask (&prev_mask
);
3390 return minus_one_ptid
;
3393 /* First check if there is a LWP with a wait status pending. */
3396 /* Any LWP that's been resumed will do. */
3397 lp
= iterate_over_lwps (ptid
, status_callback
, NULL
);
3400 if (debug_linux_nat
&& lp
->status
)
3401 fprintf_unfiltered (gdb_stdlog
,
3402 "LLW: Using pending wait status %s for %s.\n",
3403 status_to_str (lp
->status
),
3404 target_pid_to_str (lp
->ptid
));
3407 /* But if we don't find one, we'll have to wait, and check both
3408 cloned and uncloned processes. We start with the cloned
3410 options
= __WCLONE
| WNOHANG
;
3412 else if (is_lwp (ptid
))
3414 if (debug_linux_nat
)
3415 fprintf_unfiltered (gdb_stdlog
,
3416 "LLW: Waiting for specific LWP %s.\n",
3417 target_pid_to_str (ptid
));
3419 /* We have a specific LWP to check. */
3420 lp
= find_lwp_pid (ptid
);
3423 if (debug_linux_nat
&& lp
->status
)
3424 fprintf_unfiltered (gdb_stdlog
,
3425 "LLW: Using pending wait status %s for %s.\n",
3426 status_to_str (lp
->status
),
3427 target_pid_to_str (lp
->ptid
));
3429 /* If we have to wait, take into account whether PID is a cloned
3430 process or not. And we have to convert it to something that
3431 the layer beneath us can understand. */
3432 options
= lp
->cloned
? __WCLONE
: 0;
3433 pid
= GET_LWP (ptid
);
3435 /* We check for lp->waitstatus in addition to lp->status,
3436 because we can have pending process exits recorded in
3437 lp->status and W_EXITCODE(0,0) == 0. We should probably have
3438 an additional lp->status_p flag. */
3439 if (lp
->status
== 0 && lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
)
3443 if (lp
&& lp
->signalled
&& lp
->last_resume_kind
!= resume_stop
)
3445 /* A pending SIGSTOP may interfere with the normal stream of
3446 events. In a typical case where interference is a problem,
3447 we have a SIGSTOP signal pending for LWP A while
3448 single-stepping it, encounter an event in LWP B, and take the
3449 pending SIGSTOP while trying to stop LWP A. After processing
3450 the event in LWP B, LWP A is continued, and we'll never see
3451 the SIGTRAP associated with the last time we were
3452 single-stepping LWP A. */
3454 /* Resume the thread. It should halt immediately returning the
3456 registers_changed ();
3457 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3458 lp
->step
, TARGET_SIGNAL_0
);
3459 if (debug_linux_nat
)
3460 fprintf_unfiltered (gdb_stdlog
,
3461 "LLW: %s %s, 0, 0 (expect SIGSTOP)\n",
3462 lp
->step
? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3463 target_pid_to_str (lp
->ptid
));
3465 gdb_assert (lp
->resumed
);
3467 /* Catch the pending SIGSTOP. */
3468 status
= lp
->status
;
3471 stop_wait_callback (lp
, NULL
);
3473 /* If the lp->status field isn't empty, we caught another signal
3474 while flushing the SIGSTOP. Return it back to the event
3475 queue of the LWP, as we already have an event to handle. */
3478 if (debug_linux_nat
)
3479 fprintf_unfiltered (gdb_stdlog
,
3480 "LLW: kill %s, %s\n",
3481 target_pid_to_str (lp
->ptid
),
3482 status_to_str (lp
->status
));
3483 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (lp
->status
));
3486 lp
->status
= status
;
3489 if (!target_can_async_p ())
3491 /* Causes SIGINT to be passed on to the attached process. */
3495 /* Translate generic target_wait options into waitpid options. */
3496 if (target_options
& TARGET_WNOHANG
)
3503 lwpid
= my_waitpid (pid
, &status
, options
);
3507 gdb_assert (pid
== -1 || lwpid
== pid
);
3509 if (debug_linux_nat
)
3511 fprintf_unfiltered (gdb_stdlog
,
3512 "LLW: waitpid %ld received %s\n",
3513 (long) lwpid
, status_to_str (status
));
3516 lp
= linux_nat_filter_event (lwpid
, status
, options
);
3518 /* STATUS is now no longer valid, use LP->STATUS instead. */
3522 && ptid_is_pid (ptid
)
3523 && ptid_get_pid (lp
->ptid
) != ptid_get_pid (ptid
))
3525 gdb_assert (lp
->resumed
);
3527 if (debug_linux_nat
)
3529 "LWP %ld got an event %06x, leaving pending.\n",
3530 ptid_get_lwp (lp
->ptid
), lp
->status
);
3532 if (WIFSTOPPED (lp
->status
))
3534 if (WSTOPSIG (lp
->status
) != SIGSTOP
)
3536 /* Cancel breakpoint hits. The breakpoint may
3537 be removed before we fetch events from this
3538 process to report to the core. It is best
3539 not to assume the moribund breakpoints
3540 heuristic always handles these cases --- it
3541 could be too many events go through to the
3542 core before this one is handled. All-stop
3543 always cancels breakpoint hits in all
3546 && linux_nat_lp_status_is_event (lp
)
3547 && cancel_breakpoint (lp
))
3549 /* Throw away the SIGTRAP. */
3552 if (debug_linux_nat
)
3554 "LLW: LWP %ld hit a breakpoint while"
3555 " waiting for another process;"
3557 ptid_get_lwp (lp
->ptid
));
3567 else if (WIFEXITED (lp
->status
) || WIFSIGNALED (lp
->status
))
3569 if (debug_linux_nat
)
3571 "Process %ld exited while stopping LWPs\n",
3572 ptid_get_lwp (lp
->ptid
));
3574 /* This was the last lwp in the process. Since
3575 events are serialized to GDB core, and we can't
3576 report this one right now, but GDB core and the
3577 other target layers will want to be notified
3578 about the exit code/signal, leave the status
3579 pending for the next time we're able to report
3582 /* Prevent trying to stop this thread again. We'll
3583 never try to resume it because it has a pending
3587 /* Dead LWP's aren't expected to reported a pending
3591 /* Store the pending event in the waitstatus as
3592 well, because W_EXITCODE(0,0) == 0. */
3593 store_waitstatus (&lp
->waitstatus
, lp
->status
);
3607 /* waitpid did return something. Restart over. */
3608 options
|= __WCLONE
;
3616 /* Alternate between checking cloned and uncloned processes. */
3617 options
^= __WCLONE
;
3619 /* And every time we have checked both:
3620 In async mode, return to event loop;
3621 In sync mode, suspend waiting for a SIGCHLD signal. */
3622 if (options
& __WCLONE
)
3624 if (target_options
& TARGET_WNOHANG
)
3626 /* No interesting event. */
3627 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3629 if (debug_linux_nat
)
3630 fprintf_unfiltered (gdb_stdlog
, "LLW: exit (ignore)\n");
3632 restore_child_signals_mask (&prev_mask
);
3633 return minus_one_ptid
;
3636 sigsuspend (&suspend_mask
);
3639 else if (target_options
& TARGET_WNOHANG
)
3641 /* No interesting event for PID yet. */
3642 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3644 if (debug_linux_nat
)
3645 fprintf_unfiltered (gdb_stdlog
, "LLW: exit (ignore)\n");
3647 restore_child_signals_mask (&prev_mask
);
3648 return minus_one_ptid
;
3651 /* We shouldn't end up here unless we want to try again. */
3652 gdb_assert (lp
== NULL
);
3655 if (!target_can_async_p ())
3656 clear_sigint_trap ();
3660 status
= lp
->status
;
3663 /* Don't report signals that GDB isn't interested in, such as
3664 signals that are neither printed nor stopped upon. Stopping all
3665 threads can be a bit time-consuming so if we want decent
3666 performance with heavily multi-threaded programs, especially when
3667 they're using a high frequency timer, we'd better avoid it if we
3670 if (WIFSTOPPED (status
))
3672 enum target_signal signo
= target_signal_from_host (WSTOPSIG (status
));
3674 /* When using hardware single-step, we need to report every signal.
3675 Otherwise, signals in pass_mask may be short-circuited. */
3677 && WSTOPSIG (status
) && sigismember (&pass_mask
, WSTOPSIG (status
)))
3679 /* FIMXE: kettenis/2001-06-06: Should we resume all threads
3680 here? It is not clear we should. GDB may not expect
3681 other threads to run. On the other hand, not resuming
3682 newly attached threads may cause an unwanted delay in
3683 getting them running. */
3684 registers_changed ();
3685 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3687 if (debug_linux_nat
)
3688 fprintf_unfiltered (gdb_stdlog
,
3689 "LLW: %s %s, %s (preempt 'handle')\n",
3691 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3692 target_pid_to_str (lp
->ptid
),
3693 (signo
!= TARGET_SIGNAL_0
3694 ? strsignal (target_signal_to_host (signo
))
3702 /* Only do the below in all-stop, as we currently use SIGINT
3703 to implement target_stop (see linux_nat_stop) in
3705 if (signo
== TARGET_SIGNAL_INT
&& signal_pass_state (signo
) == 0)
3707 /* If ^C/BREAK is typed at the tty/console, SIGINT gets
3708 forwarded to the entire process group, that is, all LWPs
3709 will receive it - unless they're using CLONE_THREAD to
3710 share signals. Since we only want to report it once, we
3711 mark it as ignored for all LWPs except this one. */
3712 iterate_over_lwps (pid_to_ptid (ptid_get_pid (ptid
)),
3713 set_ignore_sigint
, NULL
);
3714 lp
->ignore_sigint
= 0;
3717 maybe_clear_ignore_sigint (lp
);
3721 /* This LWP is stopped now. */
3724 if (debug_linux_nat
)
3725 fprintf_unfiltered (gdb_stdlog
, "LLW: Candidate event %s in %s.\n",
3726 status_to_str (status
), target_pid_to_str (lp
->ptid
));
3730 /* Now stop all other LWP's ... */
3731 iterate_over_lwps (minus_one_ptid
, stop_callback
, NULL
);
3733 /* ... and wait until all of them have reported back that
3734 they're no longer running. */
3735 iterate_over_lwps (minus_one_ptid
, stop_wait_callback
, NULL
);
3737 /* If we're not waiting for a specific LWP, choose an event LWP
3738 from among those that have had events. Giving equal priority
3739 to all LWPs that have had events helps prevent
3742 select_event_lwp (ptid
, &lp
, &status
);
3744 /* Now that we've selected our final event LWP, cancel any
3745 breakpoints in other LWPs that have hit a GDB breakpoint.
3746 See the comment in cancel_breakpoints_callback to find out
3748 iterate_over_lwps (minus_one_ptid
, cancel_breakpoints_callback
, lp
);
3750 /* In all-stop, from the core's perspective, all LWPs are now
3751 stopped until a new resume action is sent over. */
3752 iterate_over_lwps (minus_one_ptid
, resume_clear_callback
, NULL
);
3757 lp
->last_resume_kind
= resume_stop
;
3760 if (linux_nat_status_is_event (status
))
3762 if (debug_linux_nat
)
3763 fprintf_unfiltered (gdb_stdlog
,
3764 "LLW: trap ptid is %s.\n",
3765 target_pid_to_str (lp
->ptid
));
3768 if (lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3770 *ourstatus
= lp
->waitstatus
;
3771 lp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3774 store_waitstatus (ourstatus
, status
);
3776 if (debug_linux_nat
)
3777 fprintf_unfiltered (gdb_stdlog
, "LLW: exit\n");
3779 restore_child_signals_mask (&prev_mask
);
3781 if (lp
->last_resume_kind
== resume_stop
3782 && ourstatus
->kind
== TARGET_WAITKIND_STOPPED
3783 && WSTOPSIG (status
) == SIGSTOP
)
3785 /* A thread that has been requested to stop by GDB with
3786 target_stop, and it stopped cleanly, so report as SIG0. The
3787 use of SIGSTOP is an implementation detail. */
3788 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
3791 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
3792 || ourstatus
->kind
== TARGET_WAITKIND_SIGNALLED
)
3795 lp
->core
= linux_nat_core_of_thread_1 (lp
->ptid
);
3800 /* Resume LWPs that are currently stopped without any pending status
3801 to report, but are resumed from the core's perspective. */
3804 resume_stopped_resumed_lwps (struct lwp_info
*lp
, void *data
)
3806 ptid_t
*wait_ptid_p
= data
;
3811 && lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
)
3813 gdb_assert (is_executing (lp
->ptid
));
3815 /* Don't bother if there's a breakpoint at PC that we'd hit
3816 immediately, and we're not waiting for this LWP. */
3817 if (!ptid_match (lp
->ptid
, *wait_ptid_p
))
3819 struct regcache
*regcache
= get_thread_regcache (lp
->ptid
);
3820 CORE_ADDR pc
= regcache_read_pc (regcache
);
3822 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3826 if (debug_linux_nat
)
3827 fprintf_unfiltered (gdb_stdlog
,
3828 "RSRL: resuming stopped-resumed LWP %s\n",
3829 target_pid_to_str (lp
->ptid
));
3831 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3832 lp
->step
, TARGET_SIGNAL_0
);
3834 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
3835 lp
->stopped_by_watchpoint
= 0;
3842 linux_nat_wait (struct target_ops
*ops
,
3843 ptid_t ptid
, struct target_waitstatus
*ourstatus
,
3848 if (debug_linux_nat
)
3849 fprintf_unfiltered (gdb_stdlog
,
3850 "linux_nat_wait: [%s]\n", target_pid_to_str (ptid
));
3852 /* Flush the async file first. */
3853 if (target_can_async_p ())
3854 async_file_flush ();
3856 /* Resume LWPs that are currently stopped without any pending status
3857 to report, but are resumed from the core's perspective. LWPs get
3858 in this state if we find them stopping at a time we're not
3859 interested in reporting the event (target_wait on a
3860 specific_process, for example, see linux_nat_wait_1), and
3861 meanwhile the event became uninteresting. Don't bother resuming
3862 LWPs we're not going to wait for if they'd stop immediately. */
3864 iterate_over_lwps (minus_one_ptid
, resume_stopped_resumed_lwps
, &ptid
);
3866 event_ptid
= linux_nat_wait_1 (ops
, ptid
, ourstatus
, target_options
);
3868 /* If we requested any event, and something came out, assume there
3869 may be more. If we requested a specific lwp or process, also
3870 assume there may be more. */
3871 if (target_can_async_p ()
3872 && (ourstatus
->kind
!= TARGET_WAITKIND_IGNORE
3873 || !ptid_equal (ptid
, minus_one_ptid
)))
3876 /* Get ready for the next event. */
3877 if (target_can_async_p ())
3878 target_async (inferior_event_handler
, 0);
3884 kill_callback (struct lwp_info
*lp
, void *data
)
3886 /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */
3889 kill (GET_LWP (lp
->ptid
), SIGKILL
);
3890 if (debug_linux_nat
)
3891 fprintf_unfiltered (gdb_stdlog
,
3892 "KC: kill (SIGKILL) %s, 0, 0 (%s)\n",
3893 target_pid_to_str (lp
->ptid
),
3894 errno
? safe_strerror (errno
) : "OK");
3896 /* Some kernels ignore even SIGKILL for processes under ptrace. */
3899 ptrace (PTRACE_KILL
, GET_LWP (lp
->ptid
), 0, 0);
3900 if (debug_linux_nat
)
3901 fprintf_unfiltered (gdb_stdlog
,
3902 "KC: PTRACE_KILL %s, 0, 0 (%s)\n",
3903 target_pid_to_str (lp
->ptid
),
3904 errno
? safe_strerror (errno
) : "OK");
3910 kill_wait_callback (struct lwp_info
*lp
, void *data
)
3914 /* We must make sure that there are no pending events (delayed
3915 SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current
3916 program doesn't interfere with any following debugging session. */
3918 /* For cloned processes we must check both with __WCLONE and
3919 without, since the exit status of a cloned process isn't reported
3925 pid
= my_waitpid (GET_LWP (lp
->ptid
), NULL
, __WCLONE
);
3926 if (pid
!= (pid_t
) -1)
3928 if (debug_linux_nat
)
3929 fprintf_unfiltered (gdb_stdlog
,
3930 "KWC: wait %s received unknown.\n",
3931 target_pid_to_str (lp
->ptid
));
3932 /* The Linux kernel sometimes fails to kill a thread
3933 completely after PTRACE_KILL; that goes from the stop
3934 point in do_fork out to the one in
3935 get_signal_to_deliever and waits again. So kill it
3937 kill_callback (lp
, NULL
);
3940 while (pid
== GET_LWP (lp
->ptid
));
3942 gdb_assert (pid
== -1 && errno
== ECHILD
);
3947 pid
= my_waitpid (GET_LWP (lp
->ptid
), NULL
, 0);
3948 if (pid
!= (pid_t
) -1)
3950 if (debug_linux_nat
)
3951 fprintf_unfiltered (gdb_stdlog
,
3952 "KWC: wait %s received unk.\n",
3953 target_pid_to_str (lp
->ptid
));
3954 /* See the call to kill_callback above. */
3955 kill_callback (lp
, NULL
);
3958 while (pid
== GET_LWP (lp
->ptid
));
3960 gdb_assert (pid
== -1 && errno
== ECHILD
);
3965 linux_nat_kill (struct target_ops
*ops
)
3967 struct target_waitstatus last
;
3971 /* If we're stopped while forking and we haven't followed yet,
3972 kill the other task. We need to do this first because the
3973 parent will be sleeping if this is a vfork. */
3975 get_last_target_status (&last_ptid
, &last
);
3977 if (last
.kind
== TARGET_WAITKIND_FORKED
3978 || last
.kind
== TARGET_WAITKIND_VFORKED
)
3980 ptrace (PT_KILL
, PIDGET (last
.value
.related_pid
), 0, 0);
3984 if (forks_exist_p ())
3985 linux_fork_killall ();
3988 ptid_t ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
3990 /* Stop all threads before killing them, since ptrace requires
3991 that the thread is stopped to sucessfully PTRACE_KILL. */
3992 iterate_over_lwps (ptid
, stop_callback
, NULL
);
3993 /* ... and wait until all of them have reported back that
3994 they're no longer running. */
3995 iterate_over_lwps (ptid
, stop_wait_callback
, NULL
);
3997 /* Kill all LWP's ... */
3998 iterate_over_lwps (ptid
, kill_callback
, NULL
);
4000 /* ... and wait until we've flushed all events. */
4001 iterate_over_lwps (ptid
, kill_wait_callback
, NULL
);
4004 target_mourn_inferior ();
4008 linux_nat_mourn_inferior (struct target_ops
*ops
)
4010 purge_lwp_list (ptid_get_pid (inferior_ptid
));
4012 if (! forks_exist_p ())
4013 /* Normal case, no other forks available. */
4014 linux_ops
->to_mourn_inferior (ops
);
4016 /* Multi-fork case. The current inferior_ptid has exited, but
4017 there are other viable forks to debug. Delete the exiting
4018 one and context-switch to the first available. */
4019 linux_fork_mourn_inferior ();
4022 /* Convert a native/host siginfo object, into/from the siginfo in the
4023 layout of the inferiors' architecture. */
4026 siginfo_fixup (struct siginfo
*siginfo
, gdb_byte
*inf_siginfo
, int direction
)
4030 if (linux_nat_siginfo_fixup
!= NULL
)
4031 done
= linux_nat_siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4033 /* If there was no callback, or the callback didn't do anything,
4034 then just do a straight memcpy. */
4038 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
4040 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
4045 linux_xfer_siginfo (struct target_ops
*ops
, enum target_object object
,
4046 const char *annex
, gdb_byte
*readbuf
,
4047 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
4050 struct siginfo siginfo
;
4051 gdb_byte inf_siginfo
[sizeof (struct siginfo
)];
4053 gdb_assert (object
== TARGET_OBJECT_SIGNAL_INFO
);
4054 gdb_assert (readbuf
|| writebuf
);
4056 pid
= GET_LWP (inferior_ptid
);
4058 pid
= GET_PID (inferior_ptid
);
4060 if (offset
> sizeof (siginfo
))
4064 ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
);
4068 /* When GDB is built as a 64-bit application, ptrace writes into
4069 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4070 inferior with a 64-bit GDB should look the same as debugging it
4071 with a 32-bit GDB, we need to convert it. GDB core always sees
4072 the converted layout, so any read/write will have to be done
4074 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4076 if (offset
+ len
> sizeof (siginfo
))
4077 len
= sizeof (siginfo
) - offset
;
4079 if (readbuf
!= NULL
)
4080 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4083 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4085 /* Convert back to ptrace layout before flushing it out. */
4086 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4089 ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
);
4098 linux_nat_xfer_partial (struct target_ops
*ops
, enum target_object object
,
4099 const char *annex
, gdb_byte
*readbuf
,
4100 const gdb_byte
*writebuf
,
4101 ULONGEST offset
, LONGEST len
)
4103 struct cleanup
*old_chain
;
4106 if (object
== TARGET_OBJECT_SIGNAL_INFO
)
4107 return linux_xfer_siginfo (ops
, object
, annex
, readbuf
, writebuf
,
4110 /* The target is connected but no live inferior is selected. Pass
4111 this request down to a lower stratum (e.g., the executable
4113 if (object
== TARGET_OBJECT_MEMORY
&& ptid_equal (inferior_ptid
, null_ptid
))
4116 old_chain
= save_inferior_ptid ();
4118 if (is_lwp (inferior_ptid
))
4119 inferior_ptid
= pid_to_ptid (GET_LWP (inferior_ptid
));
4121 xfer
= linux_ops
->to_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
4124 do_cleanups (old_chain
);
4129 linux_thread_alive (ptid_t ptid
)
4133 gdb_assert (is_lwp (ptid
));
4135 /* Send signal 0 instead of anything ptrace, because ptracing a
4136 running thread errors out claiming that the thread doesn't
4138 err
= kill_lwp (GET_LWP (ptid
), 0);
4140 if (debug_linux_nat
)
4141 fprintf_unfiltered (gdb_stdlog
,
4142 "LLTA: KILL(SIG0) %s (%s)\n",
4143 target_pid_to_str (ptid
),
4144 err
? safe_strerror (tmp_errno
) : "OK");
4153 linux_nat_thread_alive (struct target_ops
*ops
, ptid_t ptid
)
4155 return linux_thread_alive (ptid
);
4159 linux_nat_pid_to_str (struct target_ops
*ops
, ptid_t ptid
)
4161 static char buf
[64];
4164 && (GET_PID (ptid
) != GET_LWP (ptid
)
4165 || num_lwps (GET_PID (ptid
)) > 1))
4167 snprintf (buf
, sizeof (buf
), "LWP %ld", GET_LWP (ptid
));
4171 return normal_pid_to_str (ptid
);
4175 linux_nat_thread_name (struct thread_info
*thr
)
4177 int pid
= ptid_get_pid (thr
->ptid
);
4178 long lwp
= ptid_get_lwp (thr
->ptid
);
4179 #define FORMAT "/proc/%d/task/%ld/comm"
4180 char buf
[sizeof (FORMAT
) + 30];
4182 char *result
= NULL
;
4184 snprintf (buf
, sizeof (buf
), FORMAT
, pid
, lwp
);
4185 comm_file
= fopen (buf
, "r");
4188 /* Not exported by the kernel, so we define it here. */
4190 static char line
[COMM_LEN
+ 1];
4192 if (fgets (line
, sizeof (line
), comm_file
))
4194 char *nl
= strchr (line
, '\n');
4211 /* Accepts an integer PID; Returns a string representing a file that
4212 can be opened to get the symbols for the child process. */
4215 linux_child_pid_to_exec_file (int pid
)
4217 char *name1
, *name2
;
4219 name1
= xmalloc (MAXPATHLEN
);
4220 name2
= xmalloc (MAXPATHLEN
);
4221 make_cleanup (xfree
, name1
);
4222 make_cleanup (xfree
, name2
);
4223 memset (name2
, 0, MAXPATHLEN
);
4225 sprintf (name1
, "/proc/%d/exe", pid
);
4226 if (readlink (name1
, name2
, MAXPATHLEN
) > 0)
4232 /* Service function for corefiles and info proc. */
4235 read_mapping (FILE *mapfile
,
4240 char *device
, long long *inode
, char *filename
)
4242 int ret
= fscanf (mapfile
, "%llx-%llx %s %llx %s %llx",
4243 addr
, endaddr
, permissions
, offset
, device
, inode
);
4246 if (ret
> 0 && ret
!= EOF
)
4248 /* Eat everything up to EOL for the filename. This will prevent
4249 weird filenames (such as one with embedded whitespace) from
4250 confusing this code. It also makes this code more robust in
4251 respect to annotations the kernel may add after the filename.
4253 Note the filename is used for informational purposes
4255 ret
+= fscanf (mapfile
, "%[^\n]\n", filename
);
4258 return (ret
!= 0 && ret
!= EOF
);
4261 /* Fills the "to_find_memory_regions" target vector. Lists the memory
4262 regions in the inferior for a corefile. */
4265 linux_nat_find_memory_regions (find_memory_region_ftype func
, void *obfd
)
4267 int pid
= PIDGET (inferior_ptid
);
4268 char mapsfilename
[MAXPATHLEN
];
4270 long long addr
, endaddr
, size
, offset
, inode
;
4271 char permissions
[8], device
[8], filename
[MAXPATHLEN
];
4272 int read
, write
, exec
;
4273 struct cleanup
*cleanup
;
4275 /* Compose the filename for the /proc memory map, and open it. */
4276 sprintf (mapsfilename
, "/proc/%d/maps", pid
);
4277 if ((mapsfile
= fopen (mapsfilename
, "r")) == NULL
)
4278 error (_("Could not open %s."), mapsfilename
);
4279 cleanup
= make_cleanup_fclose (mapsfile
);
4282 fprintf_filtered (gdb_stdout
,
4283 "Reading memory regions from %s\n", mapsfilename
);
4285 /* Now iterate until end-of-file. */
4286 while (read_mapping (mapsfile
, &addr
, &endaddr
, &permissions
[0],
4287 &offset
, &device
[0], &inode
, &filename
[0]))
4289 size
= endaddr
- addr
;
4291 /* Get the segment's permissions. */
4292 read
= (strchr (permissions
, 'r') != 0);
4293 write
= (strchr (permissions
, 'w') != 0);
4294 exec
= (strchr (permissions
, 'x') != 0);
4298 fprintf_filtered (gdb_stdout
,
4299 "Save segment, %s bytes at %s (%c%c%c)",
4300 plongest (size
), paddress (target_gdbarch
, addr
),
4302 write
? 'w' : ' ', exec
? 'x' : ' ');
4304 fprintf_filtered (gdb_stdout
, " for %s", filename
);
4305 fprintf_filtered (gdb_stdout
, "\n");
4308 /* Invoke the callback function to create the corefile
4310 func (addr
, size
, read
, write
, exec
, obfd
);
4312 do_cleanups (cleanup
);
4317 find_signalled_thread (struct thread_info
*info
, void *data
)
4319 if (info
->suspend
.stop_signal
!= TARGET_SIGNAL_0
4320 && ptid_get_pid (info
->ptid
) == ptid_get_pid (inferior_ptid
))
4326 static enum target_signal
4327 find_stop_signal (void)
4329 struct thread_info
*info
=
4330 iterate_over_threads (find_signalled_thread
, NULL
);
4333 return info
->suspend
.stop_signal
;
4335 return TARGET_SIGNAL_0
;
4338 /* Records the thread's register state for the corefile note
4342 linux_nat_do_thread_registers (bfd
*obfd
, ptid_t ptid
,
4343 char *note_data
, int *note_size
,
4344 enum target_signal stop_signal
)
4346 unsigned long lwp
= ptid_get_lwp (ptid
);
4347 struct gdbarch
*gdbarch
= target_gdbarch
;
4348 struct regcache
*regcache
= get_thread_arch_regcache (ptid
, gdbarch
);
4349 const struct regset
*regset
;
4351 struct cleanup
*old_chain
;
4352 struct core_regset_section
*sect_list
;
4355 old_chain
= save_inferior_ptid ();
4356 inferior_ptid
= ptid
;
4357 target_fetch_registers (regcache
, -1);
4358 do_cleanups (old_chain
);
4360 core_regset_p
= gdbarch_regset_from_core_section_p (gdbarch
);
4361 sect_list
= gdbarch_core_regset_sections (gdbarch
);
4363 /* The loop below uses the new struct core_regset_section, which stores
4364 the supported section names and sizes for the core file. Note that
4365 note PRSTATUS needs to be treated specially. But the other notes are
4366 structurally the same, so they can benefit from the new struct. */
4367 if (core_regset_p
&& sect_list
!= NULL
)
4368 while (sect_list
->sect_name
!= NULL
)
4370 regset
= gdbarch_regset_from_core_section (gdbarch
,
4371 sect_list
->sect_name
,
4373 gdb_assert (regset
&& regset
->collect_regset
);
4374 gdb_regset
= xmalloc (sect_list
->size
);
4375 regset
->collect_regset (regset
, regcache
, -1,
4376 gdb_regset
, sect_list
->size
);
4378 if (strcmp (sect_list
->sect_name
, ".reg") == 0)
4379 note_data
= (char *) elfcore_write_prstatus
4380 (obfd
, note_data
, note_size
,
4381 lwp
, target_signal_to_host (stop_signal
),
4384 note_data
= (char *) elfcore_write_register_note
4385 (obfd
, note_data
, note_size
,
4386 sect_list
->sect_name
, gdb_regset
,
4392 /* For architectures that does not have the struct core_regset_section
4393 implemented, we use the old method. When all the architectures have
4394 the new support, the code below should be deleted. */
4397 gdb_gregset_t gregs
;
4398 gdb_fpregset_t fpregs
;
4401 && (regset
= gdbarch_regset_from_core_section (gdbarch
, ".reg",
4403 != NULL
&& regset
->collect_regset
!= NULL
)
4404 regset
->collect_regset (regset
, regcache
, -1,
4405 &gregs
, sizeof (gregs
));
4407 fill_gregset (regcache
, &gregs
, -1);
4409 note_data
= (char *) elfcore_write_prstatus
4410 (obfd
, note_data
, note_size
, lwp
, target_signal_to_host (stop_signal
),
4414 && (regset
= gdbarch_regset_from_core_section (gdbarch
, ".reg2",
4416 != NULL
&& regset
->collect_regset
!= NULL
)
4417 regset
->collect_regset (regset
, regcache
, -1,
4418 &fpregs
, sizeof (fpregs
));
4420 fill_fpregset (regcache
, &fpregs
, -1);
4422 note_data
= (char *) elfcore_write_prfpreg (obfd
,
4425 &fpregs
, sizeof (fpregs
));
4431 struct linux_nat_corefile_thread_data
4437 enum target_signal stop_signal
;
4440 /* Called by gdbthread.c once per thread. Records the thread's
4441 register state for the corefile note section. */
4444 linux_nat_corefile_thread_callback (struct lwp_info
*ti
, void *data
)
4446 struct linux_nat_corefile_thread_data
*args
= data
;
4448 args
->note_data
= linux_nat_do_thread_registers (args
->obfd
,
4458 /* Enumerate spufs IDs for process PID. */
4461 iterate_over_spus (int pid
, void (*callback
) (void *, int), void *data
)
4465 struct dirent
*entry
;
4467 xsnprintf (path
, sizeof path
, "/proc/%d/fd", pid
);
4468 dir
= opendir (path
);
4473 while ((entry
= readdir (dir
)) != NULL
)
4479 fd
= atoi (entry
->d_name
);
4483 xsnprintf (path
, sizeof path
, "/proc/%d/fd/%d", pid
, fd
);
4484 if (stat (path
, &st
) != 0)
4486 if (!S_ISDIR (st
.st_mode
))
4489 if (statfs (path
, &stfs
) != 0)
4491 if (stfs
.f_type
!= SPUFS_MAGIC
)
4494 callback (data
, fd
);
4500 /* Generate corefile notes for SPU contexts. */
4502 struct linux_spu_corefile_data
4510 linux_spu_corefile_callback (void *data
, int fd
)
4512 struct linux_spu_corefile_data
*args
= data
;
4515 static const char *spu_files
[] =
4537 for (i
= 0; i
< sizeof (spu_files
) / sizeof (spu_files
[0]); i
++)
4539 char annex
[32], note_name
[32];
4543 xsnprintf (annex
, sizeof annex
, "%d/%s", fd
, spu_files
[i
]);
4544 spu_len
= target_read_alloc (¤t_target
, TARGET_OBJECT_SPU
,
4548 xsnprintf (note_name
, sizeof note_name
, "SPU/%s", annex
);
4549 args
->note_data
= elfcore_write_note (args
->obfd
, args
->note_data
,
4550 args
->note_size
, note_name
,
4551 NT_SPU
, spu_data
, spu_len
);
4558 linux_spu_make_corefile_notes (bfd
*obfd
, char *note_data
, int *note_size
)
4560 struct linux_spu_corefile_data args
;
4563 args
.note_data
= note_data
;
4564 args
.note_size
= note_size
;
4566 iterate_over_spus (PIDGET (inferior_ptid
),
4567 linux_spu_corefile_callback
, &args
);
4569 return args
.note_data
;
4572 /* Fills the "to_make_corefile_note" target vector. Builds the note
4573 section for a corefile, and returns it in a malloc buffer. */
4576 linux_nat_make_corefile_notes (bfd
*obfd
, int *note_size
)
4578 struct linux_nat_corefile_thread_data thread_args
;
4579 /* The variable size must be >= sizeof (prpsinfo_t.pr_fname). */
4580 char fname
[16] = { '\0' };
4581 /* The variable size must be >= sizeof (prpsinfo_t.pr_psargs). */
4582 char psargs
[80] = { '\0' };
4583 char *note_data
= NULL
;
4584 ptid_t filter
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
4588 if (get_exec_file (0))
4590 strncpy (fname
, lbasename (get_exec_file (0)), sizeof (fname
));
4591 strncpy (psargs
, get_exec_file (0), sizeof (psargs
));
4592 if (get_inferior_args ())
4595 char *psargs_end
= psargs
+ sizeof (psargs
);
4597 /* linux_elfcore_write_prpsinfo () handles zero unterminated
4599 string_end
= memchr (psargs
, 0, sizeof (psargs
));
4600 if (string_end
!= NULL
)
4602 *string_end
++ = ' ';
4603 strncpy (string_end
, get_inferior_args (),
4604 psargs_end
- string_end
);
4607 note_data
= (char *) elfcore_write_prpsinfo (obfd
,
4609 note_size
, fname
, psargs
);
4612 /* Dump information for threads. */
4613 thread_args
.obfd
= obfd
;
4614 thread_args
.note_data
= note_data
;
4615 thread_args
.note_size
= note_size
;
4616 thread_args
.num_notes
= 0;
4617 thread_args
.stop_signal
= find_stop_signal ();
4618 iterate_over_lwps (filter
, linux_nat_corefile_thread_callback
, &thread_args
);
4619 gdb_assert (thread_args
.num_notes
!= 0);
4620 note_data
= thread_args
.note_data
;
4622 auxv_len
= target_read_alloc (¤t_target
, TARGET_OBJECT_AUXV
,
4626 note_data
= elfcore_write_note (obfd
, note_data
, note_size
,
4627 "CORE", NT_AUXV
, auxv
, auxv_len
);
4631 note_data
= linux_spu_make_corefile_notes (obfd
, note_data
, note_size
);
4633 make_cleanup (xfree
, note_data
);
4637 /* Implement the "info proc" command. */
4640 linux_nat_info_proc_cmd (char *args
, int from_tty
)
4642 /* A long is used for pid instead of an int to avoid a loss of precision
4643 compiler warning from the output of strtoul. */
4644 long pid
= PIDGET (inferior_ptid
);
4647 char buffer
[MAXPATHLEN
];
4648 char fname1
[MAXPATHLEN
], fname2
[MAXPATHLEN
];
4660 /* Break up 'args' into an argv array. */
4661 argv
= gdb_buildargv (args
);
4662 make_cleanup_freeargv (argv
);
4664 while (argv
!= NULL
&& *argv
!= NULL
)
4666 if (isdigit (argv
[0][0]))
4668 pid
= strtoul (argv
[0], NULL
, 10);
4670 else if (strncmp (argv
[0], "mappings", strlen (argv
[0])) == 0)
4674 else if (strcmp (argv
[0], "status") == 0)
4678 else if (strcmp (argv
[0], "stat") == 0)
4682 else if (strcmp (argv
[0], "cmd") == 0)
4686 else if (strncmp (argv
[0], "exe", strlen (argv
[0])) == 0)
4690 else if (strcmp (argv
[0], "cwd") == 0)
4694 else if (strncmp (argv
[0], "all", strlen (argv
[0])) == 0)
4700 /* [...] (future options here). */
4705 error (_("No current process: you must name one."));
4707 sprintf (fname1
, "/proc/%ld", pid
);
4708 if (stat (fname1
, &dummy
) != 0)
4709 error (_("No /proc directory: '%s'"), fname1
);
4711 printf_filtered (_("process %ld\n"), pid
);
4712 if (cmdline_f
|| all
)
4714 sprintf (fname1
, "/proc/%ld/cmdline", pid
);
4715 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4717 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
4719 if (fgets (buffer
, sizeof (buffer
), procfile
))
4720 printf_filtered ("cmdline = '%s'\n", buffer
);
4722 warning (_("unable to read '%s'"), fname1
);
4723 do_cleanups (cleanup
);
4726 warning (_("unable to open /proc file '%s'"), fname1
);
4730 sprintf (fname1
, "/proc/%ld/cwd", pid
);
4731 memset (fname2
, 0, sizeof (fname2
));
4732 if (readlink (fname1
, fname2
, sizeof (fname2
)) > 0)
4733 printf_filtered ("cwd = '%s'\n", fname2
);
4735 warning (_("unable to read link '%s'"), fname1
);
4739 sprintf (fname1
, "/proc/%ld/exe", pid
);
4740 memset (fname2
, 0, sizeof (fname2
));
4741 if (readlink (fname1
, fname2
, sizeof (fname2
)) > 0)
4742 printf_filtered ("exe = '%s'\n", fname2
);
4744 warning (_("unable to read link '%s'"), fname1
);
4746 if (mappings_f
|| all
)
4748 sprintf (fname1
, "/proc/%ld/maps", pid
);
4749 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4751 long long addr
, endaddr
, size
, offset
, inode
;
4752 char permissions
[8], device
[8], filename
[MAXPATHLEN
];
4753 struct cleanup
*cleanup
;
4755 cleanup
= make_cleanup_fclose (procfile
);
4756 printf_filtered (_("Mapped address spaces:\n\n"));
4757 if (gdbarch_addr_bit (target_gdbarch
) == 32)
4759 printf_filtered ("\t%10s %10s %10s %10s %7s\n",
4762 " Size", " Offset", "objfile");
4766 printf_filtered (" %18s %18s %10s %10s %7s\n",
4769 " Size", " Offset", "objfile");
4772 while (read_mapping (procfile
, &addr
, &endaddr
, &permissions
[0],
4773 &offset
, &device
[0], &inode
, &filename
[0]))
4775 size
= endaddr
- addr
;
4777 /* FIXME: carlton/2003-08-27: Maybe the printf_filtered
4778 calls here (and possibly above) should be abstracted
4779 out into their own functions? Andrew suggests using
4780 a generic local_address_string instead to print out
4781 the addresses; that makes sense to me, too. */
4783 if (gdbarch_addr_bit (target_gdbarch
) == 32)
4785 printf_filtered ("\t%#10lx %#10lx %#10x %#10x %7s\n",
4786 (unsigned long) addr
, /* FIXME: pr_addr */
4787 (unsigned long) endaddr
,
4789 (unsigned int) offset
,
4790 filename
[0] ? filename
: "");
4794 printf_filtered (" %#18lx %#18lx %#10x %#10x %7s\n",
4795 (unsigned long) addr
, /* FIXME: pr_addr */
4796 (unsigned long) endaddr
,
4798 (unsigned int) offset
,
4799 filename
[0] ? filename
: "");
4803 do_cleanups (cleanup
);
4806 warning (_("unable to open /proc file '%s'"), fname1
);
4808 if (status_f
|| all
)
4810 sprintf (fname1
, "/proc/%ld/status", pid
);
4811 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4813 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
4815 while (fgets (buffer
, sizeof (buffer
), procfile
) != NULL
)
4816 puts_filtered (buffer
);
4817 do_cleanups (cleanup
);
4820 warning (_("unable to open /proc file '%s'"), fname1
);
4824 sprintf (fname1
, "/proc/%ld/stat", pid
);
4825 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4830 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
4832 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4833 printf_filtered (_("Process: %d\n"), itmp
);
4834 if (fscanf (procfile
, "(%[^)]) ", &buffer
[0]) > 0)
4835 printf_filtered (_("Exec file: %s\n"), buffer
);
4836 if (fscanf (procfile
, "%c ", &ctmp
) > 0)
4837 printf_filtered (_("State: %c\n"), ctmp
);
4838 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4839 printf_filtered (_("Parent process: %d\n"), itmp
);
4840 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4841 printf_filtered (_("Process group: %d\n"), itmp
);
4842 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4843 printf_filtered (_("Session id: %d\n"), itmp
);
4844 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4845 printf_filtered (_("TTY: %d\n"), itmp
);
4846 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4847 printf_filtered (_("TTY owner process group: %d\n"), itmp
);
4848 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4849 printf_filtered (_("Flags: 0x%lx\n"), ltmp
);
4850 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4851 printf_filtered (_("Minor faults (no memory page): %lu\n"),
4852 (unsigned long) ltmp
);
4853 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4854 printf_filtered (_("Minor faults, children: %lu\n"),
4855 (unsigned long) ltmp
);
4856 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4857 printf_filtered (_("Major faults (memory page faults): %lu\n"),
4858 (unsigned long) ltmp
);
4859 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4860 printf_filtered (_("Major faults, children: %lu\n"),
4861 (unsigned long) ltmp
);
4862 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4863 printf_filtered (_("utime: %ld\n"), ltmp
);
4864 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4865 printf_filtered (_("stime: %ld\n"), ltmp
);
4866 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4867 printf_filtered (_("utime, children: %ld\n"), ltmp
);
4868 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4869 printf_filtered (_("stime, children: %ld\n"), ltmp
);
4870 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4871 printf_filtered (_("jiffies remaining in current "
4872 "time slice: %ld\n"), ltmp
);
4873 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4874 printf_filtered (_("'nice' value: %ld\n"), ltmp
);
4875 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4876 printf_filtered (_("jiffies until next timeout: %lu\n"),
4877 (unsigned long) ltmp
);
4878 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4879 printf_filtered (_("jiffies until next SIGALRM: %lu\n"),
4880 (unsigned long) ltmp
);
4881 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4882 printf_filtered (_("start time (jiffies since "
4883 "system boot): %ld\n"), ltmp
);
4884 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4885 printf_filtered (_("Virtual memory size: %lu\n"),
4886 (unsigned long) ltmp
);
4887 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4888 printf_filtered (_("Resident set size: %lu\n"),
4889 (unsigned long) ltmp
);
4890 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4891 printf_filtered (_("rlim: %lu\n"), (unsigned long) ltmp
);
4892 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4893 printf_filtered (_("Start of text: 0x%lx\n"), ltmp
);
4894 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4895 printf_filtered (_("End of text: 0x%lx\n"), ltmp
);
4896 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4897 printf_filtered (_("Start of stack: 0x%lx\n"), ltmp
);
4898 #if 0 /* Don't know how architecture-dependent the rest is...
4899 Anyway the signal bitmap info is available from "status". */
4900 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
4901 printf_filtered (_("Kernel stack pointer: 0x%lx\n"), ltmp
);
4902 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
4903 printf_filtered (_("Kernel instr pointer: 0x%lx\n"), ltmp
);
4904 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4905 printf_filtered (_("Pending signals bitmap: 0x%lx\n"), ltmp
);
4906 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4907 printf_filtered (_("Blocked signals bitmap: 0x%lx\n"), ltmp
);
4908 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4909 printf_filtered (_("Ignored signals bitmap: 0x%lx\n"), ltmp
);
4910 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4911 printf_filtered (_("Catched signals bitmap: 0x%lx\n"), ltmp
);
4912 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
4913 printf_filtered (_("wchan (system call): 0x%lx\n"), ltmp
);
4915 do_cleanups (cleanup
);
4918 warning (_("unable to open /proc file '%s'"), fname1
);
4922 /* Implement the to_xfer_partial interface for memory reads using the /proc
4923 filesystem. Because we can use a single read() call for /proc, this
4924 can be much more efficient than banging away at PTRACE_PEEKTEXT,
4925 but it doesn't support writes. */
4928 linux_proc_xfer_partial (struct target_ops
*ops
, enum target_object object
,
4929 const char *annex
, gdb_byte
*readbuf
,
4930 const gdb_byte
*writebuf
,
4931 ULONGEST offset
, LONGEST len
)
4937 if (object
!= TARGET_OBJECT_MEMORY
|| !readbuf
)
4940 /* Don't bother for one word. */
4941 if (len
< 3 * sizeof (long))
4944 /* We could keep this file open and cache it - possibly one per
4945 thread. That requires some juggling, but is even faster. */
4946 sprintf (filename
, "/proc/%d/mem", PIDGET (inferior_ptid
));
4947 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4951 /* If pread64 is available, use it. It's faster if the kernel
4952 supports it (only one syscall), and it's 64-bit safe even on
4953 32-bit platforms (for instance, SPARC debugging a SPARC64
4956 if (pread64 (fd
, readbuf
, len
, offset
) != len
)
4958 if (lseek (fd
, offset
, SEEK_SET
) == -1 || read (fd
, readbuf
, len
) != len
)
4969 /* Enumerate spufs IDs for process PID. */
4971 spu_enumerate_spu_ids (int pid
, gdb_byte
*buf
, ULONGEST offset
, LONGEST len
)
4973 enum bfd_endian byte_order
= gdbarch_byte_order (target_gdbarch
);
4975 LONGEST written
= 0;
4978 struct dirent
*entry
;
4980 xsnprintf (path
, sizeof path
, "/proc/%d/fd", pid
);
4981 dir
= opendir (path
);
4986 while ((entry
= readdir (dir
)) != NULL
)
4992 fd
= atoi (entry
->d_name
);
4996 xsnprintf (path
, sizeof path
, "/proc/%d/fd/%d", pid
, fd
);
4997 if (stat (path
, &st
) != 0)
4999 if (!S_ISDIR (st
.st_mode
))
5002 if (statfs (path
, &stfs
) != 0)
5004 if (stfs
.f_type
!= SPUFS_MAGIC
)
5007 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
5009 store_unsigned_integer (buf
+ pos
- offset
, 4, byte_order
, fd
);
5019 /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU
5020 object type, using the /proc file system. */
5022 linux_proc_xfer_spu (struct target_ops
*ops
, enum target_object object
,
5023 const char *annex
, gdb_byte
*readbuf
,
5024 const gdb_byte
*writebuf
,
5025 ULONGEST offset
, LONGEST len
)
5030 int pid
= PIDGET (inferior_ptid
);
5037 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5040 xsnprintf (buf
, sizeof buf
, "/proc/%d/fd/%s", pid
, annex
);
5041 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5046 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5053 ret
= write (fd
, writebuf
, (size_t) len
);
5055 ret
= read (fd
, readbuf
, (size_t) len
);
5062 /* Parse LINE as a signal set and add its set bits to SIGS. */
5065 add_line_to_sigset (const char *line
, sigset_t
*sigs
)
5067 int len
= strlen (line
) - 1;
5071 if (line
[len
] != '\n')
5072 error (_("Could not parse signal set: %s"), line
);
5080 if (*p
>= '0' && *p
<= '9')
5082 else if (*p
>= 'a' && *p
<= 'f')
5083 digit
= *p
- 'a' + 10;
5085 error (_("Could not parse signal set: %s"), line
);
5090 sigaddset (sigs
, signum
+ 1);
5092 sigaddset (sigs
, signum
+ 2);
5094 sigaddset (sigs
, signum
+ 3);
5096 sigaddset (sigs
, signum
+ 4);
5102 /* Find process PID's pending signals from /proc/pid/status and set
5106 linux_proc_pending_signals (int pid
, sigset_t
*pending
,
5107 sigset_t
*blocked
, sigset_t
*ignored
)
5110 char buffer
[MAXPATHLEN
], fname
[MAXPATHLEN
];
5111 struct cleanup
*cleanup
;
5113 sigemptyset (pending
);
5114 sigemptyset (blocked
);
5115 sigemptyset (ignored
);
5116 sprintf (fname
, "/proc/%d/status", pid
);
5117 procfile
= fopen (fname
, "r");
5118 if (procfile
== NULL
)
5119 error (_("Could not open %s"), fname
);
5120 cleanup
= make_cleanup_fclose (procfile
);
5122 while (fgets (buffer
, MAXPATHLEN
, procfile
) != NULL
)
5124 /* Normal queued signals are on the SigPnd line in the status
5125 file. However, 2.6 kernels also have a "shared" pending
5126 queue for delivering signals to a thread group, so check for
5129 Unfortunately some Red Hat kernels include the shared pending
5130 queue but not the ShdPnd status field. */
5132 if (strncmp (buffer
, "SigPnd:\t", 8) == 0)
5133 add_line_to_sigset (buffer
+ 8, pending
);
5134 else if (strncmp (buffer
, "ShdPnd:\t", 8) == 0)
5135 add_line_to_sigset (buffer
+ 8, pending
);
5136 else if (strncmp (buffer
, "SigBlk:\t", 8) == 0)
5137 add_line_to_sigset (buffer
+ 8, blocked
);
5138 else if (strncmp (buffer
, "SigIgn:\t", 8) == 0)
5139 add_line_to_sigset (buffer
+ 8, ignored
);
5142 do_cleanups (cleanup
);
5146 linux_nat_xfer_osdata (struct target_ops
*ops
, enum target_object object
,
5147 const char *annex
, gdb_byte
*readbuf
,
5148 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
5150 gdb_assert (object
== TARGET_OBJECT_OSDATA
);
5152 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5156 linux_xfer_partial (struct target_ops
*ops
, enum target_object object
,
5157 const char *annex
, gdb_byte
*readbuf
,
5158 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
5162 if (object
== TARGET_OBJECT_AUXV
)
5163 return memory_xfer_auxv (ops
, object
, annex
, readbuf
, writebuf
,
5166 if (object
== TARGET_OBJECT_OSDATA
)
5167 return linux_nat_xfer_osdata (ops
, object
, annex
, readbuf
, writebuf
,
5170 if (object
== TARGET_OBJECT_SPU
)
5171 return linux_proc_xfer_spu (ops
, object
, annex
, readbuf
, writebuf
,
5174 /* GDB calculates all the addresses in possibly larget width of the address.
5175 Address width needs to be masked before its final use - either by
5176 linux_proc_xfer_partial or inf_ptrace_xfer_partial.
5178 Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */
5180 if (object
== TARGET_OBJECT_MEMORY
)
5182 int addr_bit
= gdbarch_addr_bit (target_gdbarch
);
5184 if (addr_bit
< (sizeof (ULONGEST
) * HOST_CHAR_BIT
))
5185 offset
&= ((ULONGEST
) 1 << addr_bit
) - 1;
5188 xfer
= linux_proc_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
5193 return super_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
5197 /* Create a prototype generic GNU/Linux target. The client can override
5198 it with local methods. */
5201 linux_target_install_ops (struct target_ops
*t
)
5203 t
->to_insert_fork_catchpoint
= linux_child_insert_fork_catchpoint
;
5204 t
->to_remove_fork_catchpoint
= linux_child_remove_fork_catchpoint
;
5205 t
->to_insert_vfork_catchpoint
= linux_child_insert_vfork_catchpoint
;
5206 t
->to_remove_vfork_catchpoint
= linux_child_remove_vfork_catchpoint
;
5207 t
->to_insert_exec_catchpoint
= linux_child_insert_exec_catchpoint
;
5208 t
->to_remove_exec_catchpoint
= linux_child_remove_exec_catchpoint
;
5209 t
->to_set_syscall_catchpoint
= linux_child_set_syscall_catchpoint
;
5210 t
->to_pid_to_exec_file
= linux_child_pid_to_exec_file
;
5211 t
->to_post_startup_inferior
= linux_child_post_startup_inferior
;
5212 t
->to_post_attach
= linux_child_post_attach
;
5213 t
->to_follow_fork
= linux_child_follow_fork
;
5214 t
->to_find_memory_regions
= linux_nat_find_memory_regions
;
5215 t
->to_make_corefile_notes
= linux_nat_make_corefile_notes
;
5217 super_xfer_partial
= t
->to_xfer_partial
;
5218 t
->to_xfer_partial
= linux_xfer_partial
;
5224 struct target_ops
*t
;
5226 t
= inf_ptrace_target ();
5227 linux_target_install_ops (t
);
5233 linux_trad_target (CORE_ADDR (*register_u_offset
)(struct gdbarch
*, int, int))
5235 struct target_ops
*t
;
5237 t
= inf_ptrace_trad_target (register_u_offset
);
5238 linux_target_install_ops (t
);
5243 /* target_is_async_p implementation. */
5246 linux_nat_is_async_p (void)
5248 /* NOTE: palves 2008-03-21: We're only async when the user requests
5249 it explicitly with the "set target-async" command.
5250 Someday, linux will always be async. */
5251 return target_async_permitted
;
5254 /* target_can_async_p implementation. */
5257 linux_nat_can_async_p (void)
5259 /* NOTE: palves 2008-03-21: We're only async when the user requests
5260 it explicitly with the "set target-async" command.
5261 Someday, linux will always be async. */
5262 return target_async_permitted
;
5266 linux_nat_supports_non_stop (void)
5271 /* True if we want to support multi-process. To be removed when GDB
5272 supports multi-exec. */
5274 int linux_multi_process
= 1;
5277 linux_nat_supports_multi_process (void)
5279 return linux_multi_process
;
5283 linux_nat_supports_disable_randomization (void)
5285 #ifdef HAVE_PERSONALITY
5292 static int async_terminal_is_ours
= 1;
5294 /* target_terminal_inferior implementation. */
5297 linux_nat_terminal_inferior (void)
5299 if (!target_is_async_p ())
5301 /* Async mode is disabled. */
5302 terminal_inferior ();
5306 terminal_inferior ();
5308 /* Calls to target_terminal_*() are meant to be idempotent. */
5309 if (!async_terminal_is_ours
)
5312 delete_file_handler (input_fd
);
5313 async_terminal_is_ours
= 0;
5317 /* target_terminal_ours implementation. */
5320 linux_nat_terminal_ours (void)
5322 if (!target_is_async_p ())
5324 /* Async mode is disabled. */
5329 /* GDB should never give the terminal to the inferior if the
5330 inferior is running in the background (run&, continue&, etc.),
5331 but claiming it sure should. */
5334 if (async_terminal_is_ours
)
5337 clear_sigint_trap ();
5338 add_file_handler (input_fd
, stdin_event_handler
, 0);
5339 async_terminal_is_ours
= 1;
5342 static void (*async_client_callback
) (enum inferior_event_type event_type
,
5344 static void *async_client_context
;
5346 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5347 so we notice when any child changes state, and notify the
5348 event-loop; it allows us to use sigsuspend in linux_nat_wait_1
5349 above to wait for the arrival of a SIGCHLD. */
5352 sigchld_handler (int signo
)
5354 int old_errno
= errno
;
5356 if (debug_linux_nat
)
5357 ui_file_write_async_safe (gdb_stdlog
,
5358 "sigchld\n", sizeof ("sigchld\n") - 1);
5360 if (signo
== SIGCHLD
5361 && linux_nat_event_pipe
[0] != -1)
5362 async_file_mark (); /* Let the event loop know that there are
5363 events to handle. */
5368 /* Callback registered with the target events file descriptor. */
5371 handle_target_event (int error
, gdb_client_data client_data
)
5373 (*async_client_callback
) (INF_REG_EVENT
, async_client_context
);
5376 /* Create/destroy the target events pipe. Returns previous state. */
5379 linux_async_pipe (int enable
)
5381 int previous
= (linux_nat_event_pipe
[0] != -1);
5383 if (previous
!= enable
)
5387 block_child_signals (&prev_mask
);
5391 if (pipe (linux_nat_event_pipe
) == -1)
5392 internal_error (__FILE__
, __LINE__
,
5393 "creating event pipe failed.");
5395 fcntl (linux_nat_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5396 fcntl (linux_nat_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5400 close (linux_nat_event_pipe
[0]);
5401 close (linux_nat_event_pipe
[1]);
5402 linux_nat_event_pipe
[0] = -1;
5403 linux_nat_event_pipe
[1] = -1;
5406 restore_child_signals_mask (&prev_mask
);
5412 /* target_async implementation. */
5415 linux_nat_async (void (*callback
) (enum inferior_event_type event_type
,
5416 void *context
), void *context
)
5418 if (callback
!= NULL
)
5420 async_client_callback
= callback
;
5421 async_client_context
= context
;
5422 if (!linux_async_pipe (1))
5424 add_file_handler (linux_nat_event_pipe
[0],
5425 handle_target_event
, NULL
);
5426 /* There may be pending events to handle. Tell the event loop
5433 async_client_callback
= callback
;
5434 async_client_context
= context
;
5435 delete_file_handler (linux_nat_event_pipe
[0]);
5436 linux_async_pipe (0);
5441 /* Stop an LWP, and push a TARGET_SIGNAL_0 stop status if no other
5445 linux_nat_stop_lwp (struct lwp_info
*lwp
, void *data
)
5449 ptid_t ptid
= lwp
->ptid
;
5451 if (debug_linux_nat
)
5452 fprintf_unfiltered (gdb_stdlog
,
5453 "LNSL: running -> suspending %s\n",
5454 target_pid_to_str (lwp
->ptid
));
5457 if (lwp
->last_resume_kind
== resume_stop
)
5459 if (debug_linux_nat
)
5460 fprintf_unfiltered (gdb_stdlog
,
5461 "linux-nat: already stopping LWP %ld at "
5463 ptid_get_lwp (lwp
->ptid
));
5467 stop_callback (lwp
, NULL
);
5468 lwp
->last_resume_kind
= resume_stop
;
5472 /* Already known to be stopped; do nothing. */
5474 if (debug_linux_nat
)
5476 if (find_thread_ptid (lwp
->ptid
)->stop_requested
)
5477 fprintf_unfiltered (gdb_stdlog
,
5478 "LNSL: already stopped/stop_requested %s\n",
5479 target_pid_to_str (lwp
->ptid
));
5481 fprintf_unfiltered (gdb_stdlog
,
5482 "LNSL: already stopped/no "
5483 "stop_requested yet %s\n",
5484 target_pid_to_str (lwp
->ptid
));
5491 linux_nat_stop (ptid_t ptid
)
5494 iterate_over_lwps (ptid
, linux_nat_stop_lwp
, NULL
);
5496 linux_ops
->to_stop (ptid
);
5500 linux_nat_close (int quitting
)
5502 /* Unregister from the event loop. */
5503 if (target_is_async_p ())
5504 target_async (NULL
, 0);
5506 if (linux_ops
->to_close
)
5507 linux_ops
->to_close (quitting
);
5510 /* When requests are passed down from the linux-nat layer to the
5511 single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are
5512 used. The address space pointer is stored in the inferior object,
5513 but the common code that is passed such ptid can't tell whether
5514 lwpid is a "main" process id or not (it assumes so). We reverse
5515 look up the "main" process id from the lwp here. */
5517 struct address_space
*
5518 linux_nat_thread_address_space (struct target_ops
*t
, ptid_t ptid
)
5520 struct lwp_info
*lwp
;
5521 struct inferior
*inf
;
5524 pid
= GET_LWP (ptid
);
5525 if (GET_LWP (ptid
) == 0)
5527 /* An (lwpid,0,0) ptid. Look up the lwp object to get at the
5529 lwp
= find_lwp_pid (ptid
);
5530 pid
= GET_PID (lwp
->ptid
);
5534 /* A (pid,lwpid,0) ptid. */
5535 pid
= GET_PID (ptid
);
5538 inf
= find_inferior_pid (pid
);
5539 gdb_assert (inf
!= NULL
);
5544 linux_nat_core_of_thread_1 (ptid_t ptid
)
5546 struct cleanup
*back_to
;
5549 char *content
= NULL
;
5552 int content_read
= 0;
5556 filename
= xstrprintf ("/proc/%d/task/%ld/stat",
5557 GET_PID (ptid
), GET_LWP (ptid
));
5558 back_to
= make_cleanup (xfree
, filename
);
5560 f
= fopen (filename
, "r");
5563 do_cleanups (back_to
);
5567 make_cleanup_fclose (f
);
5573 content
= xrealloc (content
, content_read
+ 1024);
5574 n
= fread (content
+ content_read
, 1, 1024, f
);
5578 content
[content_read
] = '\0';
5583 make_cleanup (xfree
, content
);
5585 p
= strchr (content
, '(');
5589 p
= strchr (p
, ')');
5593 /* If the first field after program name has index 0, then core number is
5594 the field with index 36. There's no constant for that anywhere. */
5596 p
= strtok_r (p
, " ", &ts
);
5597 for (i
= 0; p
!= NULL
&& i
!= 36; ++i
)
5598 p
= strtok_r (NULL
, " ", &ts
);
5600 if (p
== NULL
|| sscanf (p
, "%d", &core
) == 0)
5603 do_cleanups (back_to
);
5608 /* Return the cached value of the processor core for thread PTID. */
5611 linux_nat_core_of_thread (struct target_ops
*ops
, ptid_t ptid
)
5613 struct lwp_info
*info
= find_lwp_pid (ptid
);
5621 linux_nat_add_target (struct target_ops
*t
)
5623 /* Save the provided single-threaded target. We save this in a separate
5624 variable because another target we've inherited from (e.g. inf-ptrace)
5625 may have saved a pointer to T; we want to use it for the final
5626 process stratum target. */
5627 linux_ops_saved
= *t
;
5628 linux_ops
= &linux_ops_saved
;
5630 /* Override some methods for multithreading. */
5631 t
->to_create_inferior
= linux_nat_create_inferior
;
5632 t
->to_attach
= linux_nat_attach
;
5633 t
->to_detach
= linux_nat_detach
;
5634 t
->to_resume
= linux_nat_resume
;
5635 t
->to_wait
= linux_nat_wait
;
5636 t
->to_pass_signals
= linux_nat_pass_signals
;
5637 t
->to_xfer_partial
= linux_nat_xfer_partial
;
5638 t
->to_kill
= linux_nat_kill
;
5639 t
->to_mourn_inferior
= linux_nat_mourn_inferior
;
5640 t
->to_thread_alive
= linux_nat_thread_alive
;
5641 t
->to_pid_to_str
= linux_nat_pid_to_str
;
5642 t
->to_thread_name
= linux_nat_thread_name
;
5643 t
->to_has_thread_control
= tc_schedlock
;
5644 t
->to_thread_address_space
= linux_nat_thread_address_space
;
5645 t
->to_stopped_by_watchpoint
= linux_nat_stopped_by_watchpoint
;
5646 t
->to_stopped_data_address
= linux_nat_stopped_data_address
;
5648 t
->to_can_async_p
= linux_nat_can_async_p
;
5649 t
->to_is_async_p
= linux_nat_is_async_p
;
5650 t
->to_supports_non_stop
= linux_nat_supports_non_stop
;
5651 t
->to_async
= linux_nat_async
;
5652 t
->to_terminal_inferior
= linux_nat_terminal_inferior
;
5653 t
->to_terminal_ours
= linux_nat_terminal_ours
;
5654 t
->to_close
= linux_nat_close
;
5656 /* Methods for non-stop support. */
5657 t
->to_stop
= linux_nat_stop
;
5659 t
->to_supports_multi_process
= linux_nat_supports_multi_process
;
5661 t
->to_supports_disable_randomization
5662 = linux_nat_supports_disable_randomization
;
5664 t
->to_core_of_thread
= linux_nat_core_of_thread
;
5666 /* We don't change the stratum; this target will sit at
5667 process_stratum and thread_db will set at thread_stratum. This
5668 is a little strange, since this is a multi-threaded-capable
5669 target, but we want to be on the stack below thread_db, and we
5670 also want to be used for single-threaded processes. */
5675 /* Register a method to call whenever a new thread is attached. */
5677 linux_nat_set_new_thread (struct target_ops
*t
, void (*new_thread
) (ptid_t
))
5679 /* Save the pointer. We only support a single registered instance
5680 of the GNU/Linux native target, so we do not need to map this to
5682 linux_nat_new_thread
= new_thread
;
5685 /* Register a method that converts a siginfo object between the layout
5686 that ptrace returns, and the layout in the architecture of the
5689 linux_nat_set_siginfo_fixup (struct target_ops
*t
,
5690 int (*siginfo_fixup
) (struct siginfo
*,
5694 /* Save the pointer. */
5695 linux_nat_siginfo_fixup
= siginfo_fixup
;
5698 /* Return the saved siginfo associated with PTID. */
5700 linux_nat_get_siginfo (ptid_t ptid
)
5702 struct lwp_info
*lp
= find_lwp_pid (ptid
);
5704 gdb_assert (lp
!= NULL
);
5706 return &lp
->siginfo
;
5709 /* Provide a prototype to silence -Wmissing-prototypes. */
5710 extern initialize_file_ftype _initialize_linux_nat
;
5713 _initialize_linux_nat (void)
5715 add_info ("proc", linux_nat_info_proc_cmd
, _("\
5716 Show /proc process information about any running process.\n\
5717 Specify any process id, or use the program being debugged by default.\n\
5718 Specify any of the following keywords for detailed info:\n\
5719 mappings -- list of mapped memory regions.\n\
5720 stat -- list a bunch of random process info.\n\
5721 status -- list a different bunch of random process info.\n\
5722 all -- list all available /proc info."));
5724 add_setshow_zinteger_cmd ("lin-lwp", class_maintenance
,
5725 &debug_linux_nat
, _("\
5726 Set debugging of GNU/Linux lwp module."), _("\
5727 Show debugging of GNU/Linux lwp module."), _("\
5728 Enables printf debugging output."),
5730 show_debug_linux_nat
,
5731 &setdebuglist
, &showdebuglist
);
5733 /* Save this mask as the default. */
5734 sigprocmask (SIG_SETMASK
, NULL
, &normal_mask
);
5736 /* Install a SIGCHLD handler. */
5737 sigchld_action
.sa_handler
= sigchld_handler
;
5738 sigemptyset (&sigchld_action
.sa_mask
);
5739 sigchld_action
.sa_flags
= SA_RESTART
;
5741 /* Make it the default. */
5742 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
5744 /* Make sure we don't block SIGCHLD during a sigsuspend. */
5745 sigprocmask (SIG_SETMASK
, NULL
, &suspend_mask
);
5746 sigdelset (&suspend_mask
, SIGCHLD
);
5748 sigemptyset (&blocked_mask
);
5752 /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to
5753 the GNU/Linux Threads library and therefore doesn't really belong
5756 /* Read variable NAME in the target and return its value if found.
5757 Otherwise return zero. It is assumed that the type of the variable
5761 get_signo (const char *name
)
5763 struct minimal_symbol
*ms
;
5766 ms
= lookup_minimal_symbol (name
, NULL
, NULL
);
5770 if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms
), (gdb_byte
*) &signo
,
5771 sizeof (signo
)) != 0)
5777 /* Return the set of signals used by the threads library in *SET. */
5780 lin_thread_get_thread_signals (sigset_t
*set
)
5782 struct sigaction action
;
5783 int restart
, cancel
;
5785 sigemptyset (&blocked_mask
);
5788 restart
= get_signo ("__pthread_sig_restart");
5789 cancel
= get_signo ("__pthread_sig_cancel");
5791 /* LinuxThreads normally uses the first two RT signals, but in some legacy
5792 cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does
5793 not provide any way for the debugger to query the signal numbers -
5794 fortunately they don't change! */
5797 restart
= __SIGRTMIN
;
5800 cancel
= __SIGRTMIN
+ 1;
5802 sigaddset (set
, restart
);
5803 sigaddset (set
, cancel
);
5805 /* The GNU/Linux Threads library makes terminating threads send a
5806 special "cancel" signal instead of SIGCHLD. Make sure we catch
5807 those (to prevent them from terminating GDB itself, which is
5808 likely to be their default action) and treat them the same way as
5811 action
.sa_handler
= sigchld_handler
;
5812 sigemptyset (&action
.sa_mask
);
5813 action
.sa_flags
= SA_RESTART
;
5814 sigaction (cancel
, &action
, NULL
);
5816 /* We block the "cancel" signal throughout this code ... */
5817 sigaddset (&blocked_mask
, cancel
);
5818 sigprocmask (SIG_BLOCK
, &blocked_mask
, NULL
);
5820 /* ... except during a sigsuspend. */
5821 sigdelset (&suspend_mask
, cancel
);