1 /* GNU/Linux native-dependent code common to multiple platforms.
3 Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include "gdb_string.h"
26 #include "gdb_assert.h"
27 #ifdef HAVE_TKILL_SYSCALL
29 #include <sys/syscall.h>
31 #include <sys/ptrace.h>
32 #include "linux-nat.h"
33 #include "linux-fork.h"
34 #include "gdbthread.h"
38 #include "inf-ptrace.h"
40 #include <sys/param.h> /* for MAXPATHLEN */
41 #include <sys/procfs.h> /* for elf_gregset etc. */
42 #include "elf-bfd.h" /* for elfcore_write_* */
43 #include "gregset.h" /* for gregset */
44 #include "gdbcore.h" /* for get_exec_file */
45 #include <ctype.h> /* for isdigit */
46 #include "gdbthread.h" /* for struct thread_info etc. */
47 #include "gdb_stat.h" /* for struct stat */
48 #include <fcntl.h> /* for O_RDONLY */
50 #include "event-loop.h"
51 #include "event-top.h"
53 #include <sys/types.h>
54 #include "gdb_dirent.h"
55 #include "xml-support.h"
61 #define SPUFS_MAGIC 0x23c9b64e
64 #ifdef HAVE_PERSONALITY
65 # include <sys/personality.h>
66 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
67 # define ADDR_NO_RANDOMIZE 0x0040000
69 #endif /* HAVE_PERSONALITY */
71 /* This comment documents high-level logic of this file.
73 Waiting for events in sync mode
74 ===============================
76 When waiting for an event in a specific thread, we just use waitpid, passing
77 the specific pid, and not passing WNOHANG.
79 When waiting for an event in all threads, waitpid is not quite good. Prior to
80 version 2.4, Linux can either wait for event in main thread, or in secondary
81 threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might
82 miss an event. The solution is to use non-blocking waitpid, together with
83 sigsuspend. First, we use non-blocking waitpid to get an event in the main
84 process, if any. Second, we use non-blocking waitpid with the __WCLONED
85 flag to check for events in cloned processes. If nothing is found, we use
86 sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something
87 happened to a child process -- and SIGCHLD will be delivered both for events
88 in main debugged process and in cloned processes. As soon as we know there's
89 an event, we get back to calling nonblocking waitpid with and without __WCLONED.
91 Note that SIGCHLD should be blocked between waitpid and sigsuspend calls,
92 so that we don't miss a signal. If SIGCHLD arrives in between, when it's
93 blocked, the signal becomes pending and sigsuspend immediately
94 notices it and returns.
96 Waiting for events in async mode
97 ================================
99 In async mode, GDB should always be ready to handle both user input
100 and target events, so neither blocking waitpid nor sigsuspend are
101 viable options. Instead, we should asynchronously notify the GDB main
102 event loop whenever there's an unprocessed event from the target. We
103 detect asynchronous target events by handling SIGCHLD signals. To
104 notify the event loop about target events, the self-pipe trick is used
105 --- a pipe is registered as waitable event source in the event loop,
106 the event loop select/poll's on the read end of this pipe (as well on
107 other event sources, e.g., stdin), and the SIGCHLD handler writes a
108 byte to this pipe. This is more portable than relying on
109 pselect/ppoll, since on kernels that lack those syscalls, libc
110 emulates them with select/poll+sigprocmask, and that is racy
111 (a.k.a. plain broken).
113 Obviously, if we fail to notify the event loop if there's a target
114 event, it's bad. OTOH, if we notify the event loop when there's no
115 event from the target, linux_nat_wait will detect that there's no real
116 event to report, and return event of type TARGET_WAITKIND_IGNORE.
117 This is mostly harmless, but it will waste time and is better avoided.
119 The main design point is that every time GDB is outside linux-nat.c,
120 we have a SIGCHLD handler installed that is called when something
121 happens to the target and notifies the GDB event loop. Whenever GDB
122 core decides to handle the event, and calls into linux-nat.c, we
123 process things as in sync mode, except that the we never block in
126 While processing an event, we may end up momentarily blocked in
127 waitpid calls. Those waitpid calls, while blocking, are guarantied to
128 return quickly. E.g., in all-stop mode, before reporting to the core
129 that an LWP hit a breakpoint, all LWPs are stopped by sending them
130 SIGSTOP, and synchronously waiting for the SIGSTOP to be reported.
131 Note that this is different from blocking indefinitely waiting for the
132 next event --- here, we're already handling an event.
137 We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another
138 signal is not entirely significant; we just need for a signal to be delivered,
139 so that we can intercept it. SIGSTOP's advantage is that it can not be
140 blocked. A disadvantage is that it is not a real-time signal, so it can only
141 be queued once; we do not keep track of other sources of SIGSTOP.
143 Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't
144 use them, because they have special behavior when the signal is generated -
145 not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL
146 kills the entire thread group.
148 A delivered SIGSTOP would stop the entire thread group, not just the thread we
149 tkill'd. But we never let the SIGSTOP be delivered; we always intercept and
150 cancel it (by PTRACE_CONT without passing SIGSTOP).
152 We could use a real-time signal instead. This would solve those problems; we
153 could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB.
154 But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH
155 generates it, and there are races with trying to find a signal that is not
159 #define O_LARGEFILE 0
162 /* If the system headers did not provide the constants, hard-code the normal
164 #ifndef PTRACE_EVENT_FORK
166 #define PTRACE_SETOPTIONS 0x4200
167 #define PTRACE_GETEVENTMSG 0x4201
169 /* options set using PTRACE_SETOPTIONS */
170 #define PTRACE_O_TRACESYSGOOD 0x00000001
171 #define PTRACE_O_TRACEFORK 0x00000002
172 #define PTRACE_O_TRACEVFORK 0x00000004
173 #define PTRACE_O_TRACECLONE 0x00000008
174 #define PTRACE_O_TRACEEXEC 0x00000010
175 #define PTRACE_O_TRACEVFORKDONE 0x00000020
176 #define PTRACE_O_TRACEEXIT 0x00000040
178 /* Wait extended result codes for the above trace options. */
179 #define PTRACE_EVENT_FORK 1
180 #define PTRACE_EVENT_VFORK 2
181 #define PTRACE_EVENT_CLONE 3
182 #define PTRACE_EVENT_EXEC 4
183 #define PTRACE_EVENT_VFORK_DONE 5
184 #define PTRACE_EVENT_EXIT 6
186 #endif /* PTRACE_EVENT_FORK */
188 /* Unlike other extended result codes, WSTOPSIG (status) on
189 PTRACE_O_TRACESYSGOOD syscall events doesn't return SIGTRAP, but
190 instead SIGTRAP with bit 7 set. */
191 #define SYSCALL_SIGTRAP (SIGTRAP | 0x80)
193 /* We can't always assume that this flag is available, but all systems
194 with the ptrace event handlers also have __WALL, so it's safe to use
197 #define __WALL 0x40000000 /* Wait for any child. */
200 #ifndef PTRACE_GETSIGINFO
201 # define PTRACE_GETSIGINFO 0x4202
202 # define PTRACE_SETSIGINFO 0x4203
205 /* The single-threaded native GNU/Linux target_ops. We save a pointer for
206 the use of the multi-threaded target. */
207 static struct target_ops
*linux_ops
;
208 static struct target_ops linux_ops_saved
;
210 /* The method to call, if any, when a new thread is attached. */
211 static void (*linux_nat_new_thread
) (ptid_t
);
213 /* The method to call, if any, when the siginfo object needs to be
214 converted between the layout returned by ptrace, and the layout in
215 the architecture of the inferior. */
216 static int (*linux_nat_siginfo_fixup
) (struct siginfo
*,
220 /* The saved to_xfer_partial method, inherited from inf-ptrace.c.
221 Called by our to_xfer_partial. */
222 static LONGEST (*super_xfer_partial
) (struct target_ops
*,
224 const char *, gdb_byte
*,
228 static int debug_linux_nat
;
230 show_debug_linux_nat (struct ui_file
*file
, int from_tty
,
231 struct cmd_list_element
*c
, const char *value
)
233 fprintf_filtered (file
, _("Debugging of GNU/Linux lwp module is %s.\n"),
237 static int debug_linux_nat_async
= 0;
239 show_debug_linux_nat_async (struct ui_file
*file
, int from_tty
,
240 struct cmd_list_element
*c
, const char *value
)
242 fprintf_filtered (file
, _("Debugging of GNU/Linux async lwp module is %s.\n"),
246 static int disable_randomization
= 1;
249 show_disable_randomization (struct ui_file
*file
, int from_tty
,
250 struct cmd_list_element
*c
, const char *value
)
252 #ifdef HAVE_PERSONALITY
253 fprintf_filtered (file
, _("\
254 Disabling randomization of debuggee's virtual address space is %s.\n"),
256 #else /* !HAVE_PERSONALITY */
258 Disabling randomization of debuggee's virtual address space is unsupported on\n\
259 this platform.\n"), file
);
260 #endif /* !HAVE_PERSONALITY */
264 set_disable_randomization (char *args
, int from_tty
, struct cmd_list_element
*c
)
266 #ifndef HAVE_PERSONALITY
268 Disabling randomization of debuggee's virtual address space is unsupported on\n\
270 #endif /* !HAVE_PERSONALITY */
273 static int linux_parent_pid
;
275 struct simple_pid_list
279 struct simple_pid_list
*next
;
281 struct simple_pid_list
*stopped_pids
;
283 /* This variable is a tri-state flag: -1 for unknown, 0 if PTRACE_O_TRACEFORK
284 can not be used, 1 if it can. */
286 static int linux_supports_tracefork_flag
= -1;
288 /* This variable is a tri-state flag: -1 for unknown, 0 if PTRACE_O_TRACESYSGOOD
289 can not be used, 1 if it can. */
291 static int linux_supports_tracesysgood_flag
= -1;
293 /* If we have PTRACE_O_TRACEFORK, this flag indicates whether we also have
294 PTRACE_O_TRACEVFORKDONE. */
296 static int linux_supports_tracevforkdone_flag
= -1;
298 /* Async mode support */
300 /* Zero if the async mode, although enabled, is masked, which means
301 linux_nat_wait should behave as if async mode was off. */
302 static int linux_nat_async_mask_value
= 1;
304 /* Stores the current used ptrace() options. */
305 static int current_ptrace_options
= 0;
307 /* The read/write ends of the pipe registered as waitable file in the
309 static int linux_nat_event_pipe
[2] = { -1, -1 };
311 /* Flush the event pipe. */
314 async_file_flush (void)
321 ret
= read (linux_nat_event_pipe
[0], &buf
, 1);
323 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
326 /* Put something (anything, doesn't matter what, or how much) in event
327 pipe, so that the select/poll in the event-loop realizes we have
328 something to process. */
331 async_file_mark (void)
335 /* It doesn't really matter what the pipe contains, as long we end
336 up with something in it. Might as well flush the previous
342 ret
= write (linux_nat_event_pipe
[1], "+", 1);
344 while (ret
== -1 && errno
== EINTR
);
346 /* Ignore EAGAIN. If the pipe is full, the event loop will already
347 be awakened anyway. */
350 static void linux_nat_async (void (*callback
)
351 (enum inferior_event_type event_type
, void *context
),
353 static int linux_nat_async_mask (int mask
);
354 static int kill_lwp (int lwpid
, int signo
);
356 static int stop_callback (struct lwp_info
*lp
, void *data
);
358 static void block_child_signals (sigset_t
*prev_mask
);
359 static void restore_child_signals_mask (sigset_t
*prev_mask
);
362 static struct lwp_info
*add_lwp (ptid_t ptid
);
363 static void purge_lwp_list (int pid
);
364 static struct lwp_info
*find_lwp_pid (ptid_t ptid
);
367 /* Trivial list manipulation functions to keep track of a list of
368 new stopped processes. */
370 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
372 struct simple_pid_list
*new_pid
= xmalloc (sizeof (struct simple_pid_list
));
374 new_pid
->status
= status
;
375 new_pid
->next
= *listp
;
380 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *status
)
382 struct simple_pid_list
**p
;
384 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
385 if ((*p
)->pid
== pid
)
387 struct simple_pid_list
*next
= (*p
)->next
;
388 *status
= (*p
)->status
;
397 linux_record_stopped_pid (int pid
, int status
)
399 add_to_pid_list (&stopped_pids
, pid
, status
);
403 /* A helper function for linux_test_for_tracefork, called after fork (). */
406 linux_tracefork_child (void)
410 ptrace (PTRACE_TRACEME
, 0, 0, 0);
411 kill (getpid (), SIGSTOP
);
416 /* Wrapper function for waitpid which handles EINTR. */
419 my_waitpid (int pid
, int *status
, int flags
)
425 ret
= waitpid (pid
, status
, flags
);
427 while (ret
== -1 && errno
== EINTR
);
432 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events.
434 First, we try to enable fork tracing on ORIGINAL_PID. If this fails,
435 we know that the feature is not available. This may change the tracing
436 options for ORIGINAL_PID, but we'll be setting them shortly anyway.
438 However, if it succeeds, we don't know for sure that the feature is
439 available; old versions of PTRACE_SETOPTIONS ignored unknown options. We
440 create a child process, attach to it, use PTRACE_SETOPTIONS to enable
441 fork tracing, and let it fork. If the process exits, we assume that we
442 can't use TRACEFORK; if we get the fork notification, and we can extract
443 the new child's PID, then we assume that we can. */
446 linux_test_for_tracefork (int original_pid
)
448 int child_pid
, ret
, status
;
452 /* We don't want those ptrace calls to be interrupted. */
453 block_child_signals (&prev_mask
);
455 linux_supports_tracefork_flag
= 0;
456 linux_supports_tracevforkdone_flag
= 0;
458 ret
= ptrace (PTRACE_SETOPTIONS
, original_pid
, 0, PTRACE_O_TRACEFORK
);
461 restore_child_signals_mask (&prev_mask
);
467 perror_with_name (("fork"));
470 linux_tracefork_child ();
472 ret
= my_waitpid (child_pid
, &status
, 0);
474 perror_with_name (("waitpid"));
475 else if (ret
!= child_pid
)
476 error (_("linux_test_for_tracefork: waitpid: unexpected result %d."), ret
);
477 if (! WIFSTOPPED (status
))
478 error (_("linux_test_for_tracefork: waitpid: unexpected status %d."), status
);
480 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0, PTRACE_O_TRACEFORK
);
483 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
486 warning (_("linux_test_for_tracefork: failed to kill child"));
487 restore_child_signals_mask (&prev_mask
);
491 ret
= my_waitpid (child_pid
, &status
, 0);
492 if (ret
!= child_pid
)
493 warning (_("linux_test_for_tracefork: failed to wait for killed child"));
494 else if (!WIFSIGNALED (status
))
495 warning (_("linux_test_for_tracefork: unexpected wait status 0x%x from "
496 "killed child"), status
);
498 restore_child_signals_mask (&prev_mask
);
502 /* Check whether PTRACE_O_TRACEVFORKDONE is available. */
503 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
504 PTRACE_O_TRACEFORK
| PTRACE_O_TRACEVFORKDONE
);
505 linux_supports_tracevforkdone_flag
= (ret
== 0);
507 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
509 warning (_("linux_test_for_tracefork: failed to resume child"));
511 ret
= my_waitpid (child_pid
, &status
, 0);
513 if (ret
== child_pid
&& WIFSTOPPED (status
)
514 && status
>> 16 == PTRACE_EVENT_FORK
)
517 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
518 if (ret
== 0 && second_pid
!= 0)
522 linux_supports_tracefork_flag
= 1;
523 my_waitpid (second_pid
, &second_status
, 0);
524 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
526 warning (_("linux_test_for_tracefork: failed to kill second child"));
527 my_waitpid (second_pid
, &status
, 0);
531 warning (_("linux_test_for_tracefork: unexpected result from waitpid "
532 "(%d, status 0x%x)"), ret
, status
);
534 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
536 warning (_("linux_test_for_tracefork: failed to kill child"));
537 my_waitpid (child_pid
, &status
, 0);
539 restore_child_signals_mask (&prev_mask
);
542 /* Determine if PTRACE_O_TRACESYSGOOD can be used to follow syscalls.
544 We try to enable syscall tracing on ORIGINAL_PID. If this fails,
545 we know that the feature is not available. This may change the tracing
546 options for ORIGINAL_PID, but we'll be setting them shortly anyway. */
549 linux_test_for_tracesysgood (int original_pid
)
554 /* We don't want those ptrace calls to be interrupted. */
555 block_child_signals (&prev_mask
);
557 linux_supports_tracesysgood_flag
= 0;
559 ret
= ptrace (PTRACE_SETOPTIONS
, original_pid
, 0, PTRACE_O_TRACESYSGOOD
);
563 linux_supports_tracesysgood_flag
= 1;
565 restore_child_signals_mask (&prev_mask
);
568 /* Determine wether we support PTRACE_O_TRACESYSGOOD option available.
569 This function also sets linux_supports_tracesysgood_flag. */
572 linux_supports_tracesysgood (int pid
)
574 if (linux_supports_tracesysgood_flag
== -1)
575 linux_test_for_tracesysgood (pid
);
576 return linux_supports_tracesysgood_flag
;
579 /* Return non-zero iff we have tracefork functionality available.
580 This function also sets linux_supports_tracefork_flag. */
583 linux_supports_tracefork (int pid
)
585 if (linux_supports_tracefork_flag
== -1)
586 linux_test_for_tracefork (pid
);
587 return linux_supports_tracefork_flag
;
591 linux_supports_tracevforkdone (int pid
)
593 if (linux_supports_tracefork_flag
== -1)
594 linux_test_for_tracefork (pid
);
595 return linux_supports_tracevforkdone_flag
;
599 linux_enable_tracesysgood (ptid_t ptid
)
601 int pid
= ptid_get_lwp (ptid
);
604 pid
= ptid_get_pid (ptid
);
606 if (linux_supports_tracesysgood (pid
) == 0)
609 current_ptrace_options
|= PTRACE_O_TRACESYSGOOD
;
611 ptrace (PTRACE_SETOPTIONS
, pid
, 0, current_ptrace_options
);
616 linux_enable_event_reporting (ptid_t ptid
)
618 int pid
= ptid_get_lwp (ptid
);
621 pid
= ptid_get_pid (ptid
);
623 if (! linux_supports_tracefork (pid
))
626 current_ptrace_options
|= PTRACE_O_TRACEFORK
| PTRACE_O_TRACEVFORK
627 | PTRACE_O_TRACEEXEC
| PTRACE_O_TRACECLONE
;
629 if (linux_supports_tracevforkdone (pid
))
630 current_ptrace_options
|= PTRACE_O_TRACEVFORKDONE
;
632 /* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to support
633 read-only process state. */
635 ptrace (PTRACE_SETOPTIONS
, pid
, 0, current_ptrace_options
);
639 linux_child_post_attach (int pid
)
641 linux_enable_event_reporting (pid_to_ptid (pid
));
642 check_for_thread_db ();
643 linux_enable_tracesysgood (pid_to_ptid (pid
));
647 linux_child_post_startup_inferior (ptid_t ptid
)
649 linux_enable_event_reporting (ptid
);
650 check_for_thread_db ();
651 linux_enable_tracesysgood (ptid
);
655 linux_child_follow_fork (struct target_ops
*ops
, int follow_child
)
659 int parent_pid
, child_pid
;
661 block_child_signals (&prev_mask
);
663 has_vforked
= (inferior_thread ()->pending_follow
.kind
664 == TARGET_WAITKIND_VFORKED
);
665 parent_pid
= ptid_get_lwp (inferior_ptid
);
667 parent_pid
= ptid_get_pid (inferior_ptid
);
668 child_pid
= PIDGET (inferior_thread ()->pending_follow
.value
.related_pid
);
671 linux_enable_event_reporting (pid_to_ptid (child_pid
));
674 && !non_stop
/* Non-stop always resumes both branches. */
675 && (!target_is_async_p () || sync_execution
)
676 && !(follow_child
|| detach_fork
|| sched_multi
))
678 /* The parent stays blocked inside the vfork syscall until the
679 child execs or exits. If we don't let the child run, then
680 the parent stays blocked. If we're telling the parent to run
681 in the foreground, the user will not be able to ctrl-c to get
682 back the terminal, effectively hanging the debug session. */
683 fprintf_filtered (gdb_stderr
, _("\
684 Can not resume the parent process over vfork in the foreground while \n\
685 holding the child stopped. Try \"set detach-on-fork\" or \
686 \"set schedule-multiple\".\n"));
692 struct lwp_info
*child_lp
= NULL
;
694 /* We're already attached to the parent, by default. */
696 /* Detach new forked process? */
699 /* Before detaching from the child, remove all breakpoints
700 from it. If we forked, then this has already been taken
701 care of by infrun.c. If we vforked however, any
702 breakpoint inserted in the parent is visible in the
703 child, even those added while stopped in a vfork
704 catchpoint. This will remove the breakpoints from the
705 parent also, but they'll be reinserted below. */
708 /* keep breakpoints list in sync. */
709 remove_breakpoints_pid (GET_PID (inferior_ptid
));
712 if (info_verbose
|| debug_linux_nat
)
714 target_terminal_ours ();
715 fprintf_filtered (gdb_stdlog
,
716 "Detaching after fork from child process %d.\n",
720 ptrace (PTRACE_DETACH
, child_pid
, 0, 0);
724 struct inferior
*parent_inf
, *child_inf
;
725 struct cleanup
*old_chain
;
727 /* Add process to GDB's tables. */
728 child_inf
= add_inferior (child_pid
);
730 parent_inf
= current_inferior ();
731 child_inf
->attach_flag
= parent_inf
->attach_flag
;
732 copy_terminal_info (child_inf
, parent_inf
);
734 old_chain
= save_inferior_ptid ();
735 save_current_program_space ();
737 inferior_ptid
= ptid_build (child_pid
, child_pid
, 0);
738 add_thread (inferior_ptid
);
739 child_lp
= add_lwp (inferior_ptid
);
740 child_lp
->stopped
= 1;
741 child_lp
->resumed
= 1;
743 /* If this is a vfork child, then the address-space is
744 shared with the parent. */
747 child_inf
->pspace
= parent_inf
->pspace
;
748 child_inf
->aspace
= parent_inf
->aspace
;
750 /* The parent will be frozen until the child is done
751 with the shared region. Keep track of the
753 child_inf
->vfork_parent
= parent_inf
;
754 child_inf
->pending_detach
= 0;
755 parent_inf
->vfork_child
= child_inf
;
756 parent_inf
->pending_detach
= 0;
760 child_inf
->aspace
= new_address_space ();
761 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
762 child_inf
->removable
= 1;
763 set_current_program_space (child_inf
->pspace
);
764 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
766 /* Let the shared library layer (solib-svr4) learn about
767 this new process, relocate the cloned exec, pull in
768 shared libraries, and install the solib event
769 breakpoint. If a "cloned-VM" event was propagated
770 better throughout the core, this wouldn't be
772 solib_create_inferior_hook ();
775 /* Let the thread_db layer learn about this new process. */
776 check_for_thread_db ();
778 do_cleanups (old_chain
);
784 struct inferior
*parent_inf
;
786 parent_inf
= current_inferior ();
788 /* If we detached from the child, then we have to be careful
789 to not insert breakpoints in the parent until the child
790 is done with the shared memory region. However, if we're
791 staying attached to the child, then we can and should
792 insert breakpoints, so that we can debug it. A
793 subsequent child exec or exit is enough to know when does
794 the child stops using the parent's address space. */
795 parent_inf
->waiting_for_vfork_done
= detach_fork
;
796 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
798 lp
= find_lwp_pid (pid_to_ptid (parent_pid
));
799 gdb_assert (linux_supports_tracefork_flag
>= 0);
800 if (linux_supports_tracevforkdone (0))
803 fprintf_unfiltered (gdb_stdlog
,
804 "LCFF: waiting for VFORK_DONE on %d\n",
810 /* We'll handle the VFORK_DONE event like any other
811 event, in target_wait. */
815 /* We can't insert breakpoints until the child has
816 finished with the shared memory region. We need to
817 wait until that happens. Ideal would be to just
819 - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0);
820 - waitpid (parent_pid, &status, __WALL);
821 However, most architectures can't handle a syscall
822 being traced on the way out if it wasn't traced on
825 We might also think to loop, continuing the child
826 until it exits or gets a SIGTRAP. One problem is
827 that the child might call ptrace with PTRACE_TRACEME.
829 There's no simple and reliable way to figure out when
830 the vforked child will be done with its copy of the
831 shared memory. We could step it out of the syscall,
832 two instructions, let it go, and then single-step the
833 parent once. When we have hardware single-step, this
834 would work; with software single-step it could still
835 be made to work but we'd have to be able to insert
836 single-step breakpoints in the child, and we'd have
837 to insert -just- the single-step breakpoint in the
838 parent. Very awkward.
840 In the end, the best we can do is to make sure it
841 runs for a little while. Hopefully it will be out of
842 range of any breakpoints we reinsert. Usually this
843 is only the single-step breakpoint at vfork's return
847 fprintf_unfiltered (gdb_stdlog
,
848 "LCFF: no VFORK_DONE support, sleeping a bit\n");
852 /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event,
853 and leave it pending. The next linux_nat_resume call
854 will notice a pending event, and bypasses actually
855 resuming the inferior. */
857 lp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
861 /* If we're in async mode, need to tell the event loop
862 there's something here to process. */
863 if (target_can_async_p ())
870 struct thread_info
*tp
;
871 struct inferior
*parent_inf
, *child_inf
;
873 struct program_space
*parent_pspace
;
875 if (info_verbose
|| debug_linux_nat
)
877 target_terminal_ours ();
879 fprintf_filtered (gdb_stdlog
, _("\
880 Attaching after process %d vfork to child process %d.\n"),
881 parent_pid
, child_pid
);
883 fprintf_filtered (gdb_stdlog
, _("\
884 Attaching after process %d fork to child process %d.\n"),
885 parent_pid
, child_pid
);
888 /* Add the new inferior first, so that the target_detach below
889 doesn't unpush the target. */
891 child_inf
= add_inferior (child_pid
);
893 parent_inf
= current_inferior ();
894 child_inf
->attach_flag
= parent_inf
->attach_flag
;
895 copy_terminal_info (child_inf
, parent_inf
);
897 parent_pspace
= parent_inf
->pspace
;
899 /* If we're vforking, we want to hold on to the parent until the
900 child exits or execs. At child exec or exit time we can
901 remove the old breakpoints from the parent and detach or
902 resume debugging it. Otherwise, detach the parent now; we'll
903 want to reuse it's program/address spaces, but we can't set
904 them to the child before removing breakpoints from the
905 parent, otherwise, the breakpoints module could decide to
906 remove breakpoints from the wrong process (since they'd be
907 assigned to the same address space). */
911 gdb_assert (child_inf
->vfork_parent
== NULL
);
912 gdb_assert (parent_inf
->vfork_child
== NULL
);
913 child_inf
->vfork_parent
= parent_inf
;
914 child_inf
->pending_detach
= 0;
915 parent_inf
->vfork_child
= child_inf
;
916 parent_inf
->pending_detach
= detach_fork
;
917 parent_inf
->waiting_for_vfork_done
= 0;
919 else if (detach_fork
)
920 target_detach (NULL
, 0);
922 /* Note that the detach above makes PARENT_INF dangling. */
924 /* Add the child thread to the appropriate lists, and switch to
925 this new thread, before cloning the program space, and
926 informing the solib layer about this new process. */
928 inferior_ptid
= ptid_build (child_pid
, child_pid
, 0);
929 add_thread (inferior_ptid
);
930 lp
= add_lwp (inferior_ptid
);
934 /* If this is a vfork child, then the address-space is shared
935 with the parent. If we detached from the parent, then we can
936 reuse the parent's program/address spaces. */
937 if (has_vforked
|| detach_fork
)
939 child_inf
->pspace
= parent_pspace
;
940 child_inf
->aspace
= child_inf
->pspace
->aspace
;
944 child_inf
->aspace
= new_address_space ();
945 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
946 child_inf
->removable
= 1;
947 set_current_program_space (child_inf
->pspace
);
948 clone_program_space (child_inf
->pspace
, parent_pspace
);
950 /* Let the shared library layer (solib-svr4) learn about
951 this new process, relocate the cloned exec, pull in
952 shared libraries, and install the solib event breakpoint.
953 If a "cloned-VM" event was propagated better throughout
954 the core, this wouldn't be required. */
955 solib_create_inferior_hook ();
958 /* Let the thread_db layer learn about this new process. */
959 check_for_thread_db ();
962 restore_child_signals_mask (&prev_mask
);
968 linux_child_insert_fork_catchpoint (int pid
)
970 if (! linux_supports_tracefork (pid
))
971 error (_("Your system does not support fork catchpoints."));
975 linux_child_insert_vfork_catchpoint (int pid
)
977 if (!linux_supports_tracefork (pid
))
978 error (_("Your system does not support vfork catchpoints."));
982 linux_child_insert_exec_catchpoint (int pid
)
984 if (!linux_supports_tracefork (pid
))
985 error (_("Your system does not support exec catchpoints."));
989 linux_child_set_syscall_catchpoint (int pid
, int needed
, int any_count
,
990 int table_size
, int *table
)
992 if (! linux_supports_tracesysgood (pid
))
993 error (_("Your system does not support syscall catchpoints."));
994 /* On GNU/Linux, we ignore the arguments. It means that we only
995 enable the syscall catchpoints, but do not disable them.
997 Also, we do not use the `table' information because we do not
998 filter system calls here. We let GDB do the logic for us. */
1002 /* On GNU/Linux there are no real LWP's. The closest thing to LWP's
1003 are processes sharing the same VM space. A multi-threaded process
1004 is basically a group of such processes. However, such a grouping
1005 is almost entirely a user-space issue; the kernel doesn't enforce
1006 such a grouping at all (this might change in the future). In
1007 general, we'll rely on the threads library (i.e. the GNU/Linux
1008 Threads library) to provide such a grouping.
1010 It is perfectly well possible to write a multi-threaded application
1011 without the assistance of a threads library, by using the clone
1012 system call directly. This module should be able to give some
1013 rudimentary support for debugging such applications if developers
1014 specify the CLONE_PTRACE flag in the clone system call, and are
1015 using the Linux kernel 2.4 or above.
1017 Note that there are some peculiarities in GNU/Linux that affect
1020 - In general one should specify the __WCLONE flag to waitpid in
1021 order to make it report events for any of the cloned processes
1022 (and leave it out for the initial process). However, if a cloned
1023 process has exited the exit status is only reported if the
1024 __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but
1025 we cannot use it since GDB must work on older systems too.
1027 - When a traced, cloned process exits and is waited for by the
1028 debugger, the kernel reassigns it to the original parent and
1029 keeps it around as a "zombie". Somehow, the GNU/Linux Threads
1030 library doesn't notice this, which leads to the "zombie problem":
1031 When debugged a multi-threaded process that spawns a lot of
1032 threads will run out of processes, even if the threads exit,
1033 because the "zombies" stay around. */
1035 /* List of known LWPs. */
1036 struct lwp_info
*lwp_list
;
1039 /* Original signal mask. */
1040 static sigset_t normal_mask
;
1042 /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in
1043 _initialize_linux_nat. */
1044 static sigset_t suspend_mask
;
1046 /* Signals to block to make that sigsuspend work. */
1047 static sigset_t blocked_mask
;
1049 /* SIGCHLD action. */
1050 struct sigaction sigchld_action
;
1052 /* Block child signals (SIGCHLD and linux threads signals), and store
1053 the previous mask in PREV_MASK. */
1056 block_child_signals (sigset_t
*prev_mask
)
1058 /* Make sure SIGCHLD is blocked. */
1059 if (!sigismember (&blocked_mask
, SIGCHLD
))
1060 sigaddset (&blocked_mask
, SIGCHLD
);
1062 sigprocmask (SIG_BLOCK
, &blocked_mask
, prev_mask
);
1065 /* Restore child signals mask, previously returned by
1066 block_child_signals. */
1069 restore_child_signals_mask (sigset_t
*prev_mask
)
1071 sigprocmask (SIG_SETMASK
, prev_mask
, NULL
);
1075 /* Prototypes for local functions. */
1076 static int stop_wait_callback (struct lwp_info
*lp
, void *data
);
1077 static int linux_thread_alive (ptid_t ptid
);
1078 static char *linux_child_pid_to_exec_file (int pid
);
1079 static int cancel_breakpoint (struct lwp_info
*lp
);
1082 /* Convert wait status STATUS to a string. Used for printing debug
1086 status_to_str (int status
)
1088 static char buf
[64];
1090 if (WIFSTOPPED (status
))
1092 if (WSTOPSIG (status
) == SYSCALL_SIGTRAP
)
1093 snprintf (buf
, sizeof (buf
), "%s (stopped at syscall)",
1094 strsignal (SIGTRAP
));
1096 snprintf (buf
, sizeof (buf
), "%s (stopped)",
1097 strsignal (WSTOPSIG (status
)));
1099 else if (WIFSIGNALED (status
))
1100 snprintf (buf
, sizeof (buf
), "%s (terminated)",
1101 strsignal (WSTOPSIG (status
)));
1103 snprintf (buf
, sizeof (buf
), "%d (exited)", WEXITSTATUS (status
));
1108 /* Initialize the list of LWPs. Note that this module, contrary to
1109 what GDB's generic threads layer does for its thread list,
1110 re-initializes the LWP lists whenever we mourn or detach (which
1111 doesn't involve mourning) the inferior. */
1114 init_lwp_list (void)
1116 struct lwp_info
*lp
, *lpnext
;
1118 for (lp
= lwp_list
; lp
; lp
= lpnext
)
1127 /* Remove all LWPs belong to PID from the lwp list. */
1130 purge_lwp_list (int pid
)
1132 struct lwp_info
*lp
, *lpprev
, *lpnext
;
1136 for (lp
= lwp_list
; lp
; lp
= lpnext
)
1140 if (ptid_get_pid (lp
->ptid
) == pid
)
1143 lwp_list
= lp
->next
;
1145 lpprev
->next
= lp
->next
;
1154 /* Return the number of known LWPs in the tgid given by PID. */
1160 struct lwp_info
*lp
;
1162 for (lp
= lwp_list
; lp
; lp
= lp
->next
)
1163 if (ptid_get_pid (lp
->ptid
) == pid
)
1169 /* Add the LWP specified by PID to the list. Return a pointer to the
1170 structure describing the new LWP. The LWP should already be stopped
1171 (with an exception for the very first LWP). */
1173 static struct lwp_info
*
1174 add_lwp (ptid_t ptid
)
1176 struct lwp_info
*lp
;
1178 gdb_assert (is_lwp (ptid
));
1180 lp
= (struct lwp_info
*) xmalloc (sizeof (struct lwp_info
));
1182 memset (lp
, 0, sizeof (struct lwp_info
));
1184 lp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
1188 lp
->next
= lwp_list
;
1191 if (num_lwps (GET_PID (ptid
)) > 1 && linux_nat_new_thread
!= NULL
)
1192 linux_nat_new_thread (ptid
);
1197 /* Remove the LWP specified by PID from the list. */
1200 delete_lwp (ptid_t ptid
)
1202 struct lwp_info
*lp
, *lpprev
;
1206 for (lp
= lwp_list
; lp
; lpprev
= lp
, lp
= lp
->next
)
1207 if (ptid_equal (lp
->ptid
, ptid
))
1214 lpprev
->next
= lp
->next
;
1216 lwp_list
= lp
->next
;
1221 /* Return a pointer to the structure describing the LWP corresponding
1222 to PID. If no corresponding LWP could be found, return NULL. */
1224 static struct lwp_info
*
1225 find_lwp_pid (ptid_t ptid
)
1227 struct lwp_info
*lp
;
1231 lwp
= GET_LWP (ptid
);
1233 lwp
= GET_PID (ptid
);
1235 for (lp
= lwp_list
; lp
; lp
= lp
->next
)
1236 if (lwp
== GET_LWP (lp
->ptid
))
1242 /* Returns true if PTID matches filter FILTER. FILTER can be the wild
1243 card MINUS_ONE_PTID (all ptid match it); can be a ptid representing
1244 a process (ptid_is_pid returns true), in which case, all lwps of
1245 that give process match, lwps of other process do not; or, it can
1246 represent a specific thread, in which case, only that thread will
1247 match true. PTID must represent an LWP, it can never be a wild
1251 ptid_match (ptid_t ptid
, ptid_t filter
)
1253 /* Since both parameters have the same type, prevent easy mistakes
1255 gdb_assert (!ptid_equal (ptid
, minus_one_ptid
)
1256 && !ptid_equal (ptid
, null_ptid
));
1258 if (ptid_equal (filter
, minus_one_ptid
))
1260 if (ptid_is_pid (filter
)
1261 && ptid_get_pid (ptid
) == ptid_get_pid (filter
))
1263 else if (ptid_equal (ptid
, filter
))
1269 /* Call CALLBACK with its second argument set to DATA for every LWP in
1270 the list. If CALLBACK returns 1 for a particular LWP, return a
1271 pointer to the structure describing that LWP immediately.
1272 Otherwise return NULL. */
1275 iterate_over_lwps (ptid_t filter
,
1276 int (*callback
) (struct lwp_info
*, void *),
1279 struct lwp_info
*lp
, *lpnext
;
1281 for (lp
= lwp_list
; lp
; lp
= lpnext
)
1285 if (ptid_match (lp
->ptid
, filter
))
1287 if ((*callback
) (lp
, data
))
1295 /* Update our internal state when changing from one checkpoint to
1296 another indicated by NEW_PTID. We can only switch single-threaded
1297 applications, so we only create one new LWP, and the previous list
1301 linux_nat_switch_fork (ptid_t new_ptid
)
1303 struct lwp_info
*lp
;
1305 purge_lwp_list (GET_PID (inferior_ptid
));
1307 lp
= add_lwp (new_ptid
);
1310 /* This changes the thread's ptid while preserving the gdb thread
1311 num. Also changes the inferior pid, while preserving the
1313 thread_change_ptid (inferior_ptid
, new_ptid
);
1315 /* We've just told GDB core that the thread changed target id, but,
1316 in fact, it really is a different thread, with different register
1318 registers_changed ();
1321 /* Handle the exit of a single thread LP. */
1324 exit_lwp (struct lwp_info
*lp
)
1326 struct thread_info
*th
= find_thread_ptid (lp
->ptid
);
1330 if (print_thread_events
)
1331 printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp
->ptid
));
1333 delete_thread (lp
->ptid
);
1336 delete_lwp (lp
->ptid
);
1339 /* Return an lwp's tgid, found in `/proc/PID/status'. */
1342 linux_proc_get_tgid (int lwpid
)
1348 snprintf (buf
, sizeof (buf
), "/proc/%d/status", (int) lwpid
);
1349 status_file
= fopen (buf
, "r");
1350 if (status_file
!= NULL
)
1352 while (fgets (buf
, sizeof (buf
), status_file
))
1354 if (strncmp (buf
, "Tgid:", 5) == 0)
1356 tgid
= strtoul (buf
+ strlen ("Tgid:"), NULL
, 10);
1361 fclose (status_file
);
1367 /* Detect `T (stopped)' in `/proc/PID/status'.
1368 Other states including `T (tracing stop)' are reported as false. */
1371 pid_is_stopped (pid_t pid
)
1377 snprintf (buf
, sizeof (buf
), "/proc/%d/status", (int) pid
);
1378 status_file
= fopen (buf
, "r");
1379 if (status_file
!= NULL
)
1383 while (fgets (buf
, sizeof (buf
), status_file
))
1385 if (strncmp (buf
, "State:", 6) == 0)
1391 if (have_state
&& strstr (buf
, "T (stopped)") != NULL
)
1393 fclose (status_file
);
1398 /* Wait for the LWP specified by LP, which we have just attached to.
1399 Returns a wait status for that LWP, to cache. */
1402 linux_nat_post_attach_wait (ptid_t ptid
, int first
, int *cloned
,
1405 pid_t new_pid
, pid
= GET_LWP (ptid
);
1408 if (pid_is_stopped (pid
))
1410 if (debug_linux_nat
)
1411 fprintf_unfiltered (gdb_stdlog
,
1412 "LNPAW: Attaching to a stopped process\n");
1414 /* The process is definitely stopped. It is in a job control
1415 stop, unless the kernel predates the TASK_STOPPED /
1416 TASK_TRACED distinction, in which case it might be in a
1417 ptrace stop. Make sure it is in a ptrace stop; from there we
1418 can kill it, signal it, et cetera.
1420 First make sure there is a pending SIGSTOP. Since we are
1421 already attached, the process can not transition from stopped
1422 to running without a PTRACE_CONT; so we know this signal will
1423 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1424 probably already in the queue (unless this kernel is old
1425 enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP
1426 is not an RT signal, it can only be queued once. */
1427 kill_lwp (pid
, SIGSTOP
);
1429 /* Finally, resume the stopped process. This will deliver the SIGSTOP
1430 (or a higher priority signal, just like normal PTRACE_ATTACH). */
1431 ptrace (PTRACE_CONT
, pid
, 0, 0);
1434 /* Make sure the initial process is stopped. The user-level threads
1435 layer might want to poke around in the inferior, and that won't
1436 work if things haven't stabilized yet. */
1437 new_pid
= my_waitpid (pid
, &status
, 0);
1438 if (new_pid
== -1 && errno
== ECHILD
)
1441 warning (_("%s is a cloned process"), target_pid_to_str (ptid
));
1443 /* Try again with __WCLONE to check cloned processes. */
1444 new_pid
= my_waitpid (pid
, &status
, __WCLONE
);
1448 gdb_assert (pid
== new_pid
);
1450 if (!WIFSTOPPED (status
))
1452 /* The pid we tried to attach has apparently just exited. */
1453 if (debug_linux_nat
)
1454 fprintf_unfiltered (gdb_stdlog
, "LNPAW: Failed to stop %d: %s",
1455 pid
, status_to_str (status
));
1459 if (WSTOPSIG (status
) != SIGSTOP
)
1462 if (debug_linux_nat
)
1463 fprintf_unfiltered (gdb_stdlog
,
1464 "LNPAW: Received %s after attaching\n",
1465 status_to_str (status
));
1471 /* Attach to the LWP specified by PID. Return 0 if successful or -1
1472 if the new LWP could not be attached. */
1475 lin_lwp_attach_lwp (ptid_t ptid
)
1477 struct lwp_info
*lp
;
1480 gdb_assert (is_lwp (ptid
));
1482 block_child_signals (&prev_mask
);
1484 lp
= find_lwp_pid (ptid
);
1486 /* We assume that we're already attached to any LWP that has an id
1487 equal to the overall process id, and to any LWP that is already
1488 in our list of LWPs. If we're not seeing exit events from threads
1489 and we've had PID wraparound since we last tried to stop all threads,
1490 this assumption might be wrong; fortunately, this is very unlikely
1492 if (GET_LWP (ptid
) != GET_PID (ptid
) && lp
== NULL
)
1494 int status
, cloned
= 0, signalled
= 0;
1496 if (ptrace (PTRACE_ATTACH
, GET_LWP (ptid
), 0, 0) < 0)
1498 /* If we fail to attach to the thread, issue a warning,
1499 but continue. One way this can happen is if thread
1500 creation is interrupted; as of Linux kernel 2.6.19, a
1501 bug may place threads in the thread list and then fail
1503 warning (_("Can't attach %s: %s"), target_pid_to_str (ptid
),
1504 safe_strerror (errno
));
1505 restore_child_signals_mask (&prev_mask
);
1509 if (debug_linux_nat
)
1510 fprintf_unfiltered (gdb_stdlog
,
1511 "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n",
1512 target_pid_to_str (ptid
));
1514 status
= linux_nat_post_attach_wait (ptid
, 0, &cloned
, &signalled
);
1515 if (!WIFSTOPPED (status
))
1518 lp
= add_lwp (ptid
);
1520 lp
->cloned
= cloned
;
1521 lp
->signalled
= signalled
;
1522 if (WSTOPSIG (status
) != SIGSTOP
)
1525 lp
->status
= status
;
1528 target_post_attach (GET_LWP (lp
->ptid
));
1530 if (debug_linux_nat
)
1532 fprintf_unfiltered (gdb_stdlog
,
1533 "LLAL: waitpid %s received %s\n",
1534 target_pid_to_str (ptid
),
1535 status_to_str (status
));
1540 /* We assume that the LWP representing the original process is
1541 already stopped. Mark it as stopped in the data structure
1542 that the GNU/linux ptrace layer uses to keep track of
1543 threads. Note that this won't have already been done since
1544 the main thread will have, we assume, been stopped by an
1545 attach from a different layer. */
1547 lp
= add_lwp (ptid
);
1551 restore_child_signals_mask (&prev_mask
);
1556 linux_nat_create_inferior (struct target_ops
*ops
,
1557 char *exec_file
, char *allargs
, char **env
,
1560 #ifdef HAVE_PERSONALITY
1561 int personality_orig
= 0, personality_set
= 0;
1562 #endif /* HAVE_PERSONALITY */
1564 /* The fork_child mechanism is synchronous and calls target_wait, so
1565 we have to mask the async mode. */
1567 #ifdef HAVE_PERSONALITY
1568 if (disable_randomization
)
1571 personality_orig
= personality (0xffffffff);
1572 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
1574 personality_set
= 1;
1575 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
1577 if (errno
!= 0 || (personality_set
1578 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
1579 warning (_("Error disabling address space randomization: %s"),
1580 safe_strerror (errno
));
1582 #endif /* HAVE_PERSONALITY */
1584 linux_ops
->to_create_inferior (ops
, exec_file
, allargs
, env
, from_tty
);
1586 #ifdef HAVE_PERSONALITY
1587 if (personality_set
)
1590 personality (personality_orig
);
1592 warning (_("Error restoring address space randomization: %s"),
1593 safe_strerror (errno
));
1595 #endif /* HAVE_PERSONALITY */
1599 linux_nat_attach (struct target_ops
*ops
, char *args
, int from_tty
)
1601 struct lwp_info
*lp
;
1605 linux_ops
->to_attach (ops
, args
, from_tty
);
1607 /* The ptrace base target adds the main thread with (pid,0,0)
1608 format. Decorate it with lwp info. */
1609 ptid
= BUILD_LWP (GET_PID (inferior_ptid
), GET_PID (inferior_ptid
));
1610 thread_change_ptid (inferior_ptid
, ptid
);
1612 /* Add the initial process as the first LWP to the list. */
1613 lp
= add_lwp (ptid
);
1615 status
= linux_nat_post_attach_wait (lp
->ptid
, 1, &lp
->cloned
,
1617 if (!WIFSTOPPED (status
))
1619 if (WIFEXITED (status
))
1621 int exit_code
= WEXITSTATUS (status
);
1623 target_terminal_ours ();
1624 target_mourn_inferior ();
1626 error (_("Unable to attach: program exited normally."));
1628 error (_("Unable to attach: program exited with code %d."),
1631 else if (WIFSIGNALED (status
))
1633 enum target_signal signo
;
1635 target_terminal_ours ();
1636 target_mourn_inferior ();
1638 signo
= target_signal_from_host (WTERMSIG (status
));
1639 error (_("Unable to attach: program terminated with signal "
1641 target_signal_to_name (signo
),
1642 target_signal_to_string (signo
));
1645 internal_error (__FILE__
, __LINE__
,
1646 _("unexpected status %d for PID %ld"),
1647 status
, (long) GET_LWP (ptid
));
1652 /* Save the wait status to report later. */
1654 if (debug_linux_nat
)
1655 fprintf_unfiltered (gdb_stdlog
,
1656 "LNA: waitpid %ld, saving status %s\n",
1657 (long) GET_PID (lp
->ptid
), status_to_str (status
));
1659 lp
->status
= status
;
1661 if (target_can_async_p ())
1662 target_async (inferior_event_handler
, 0);
1665 /* Get pending status of LP. */
1667 get_pending_status (struct lwp_info
*lp
, int *status
)
1669 enum target_signal signo
= TARGET_SIGNAL_0
;
1671 /* If we paused threads momentarily, we may have stored pending
1672 events in lp->status or lp->waitstatus (see stop_wait_callback),
1673 and GDB core hasn't seen any signal for those threads.
1674 Otherwise, the last signal reported to the core is found in the
1675 thread object's stop_signal.
1677 There's a corner case that isn't handled here at present. Only
1678 if the thread stopped with a TARGET_WAITKIND_STOPPED does
1679 stop_signal make sense as a real signal to pass to the inferior.
1680 Some catchpoint related events, like
1681 TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set
1682 to TARGET_SIGNAL_SIGTRAP when the catchpoint triggers. But,
1683 those traps are debug API (ptrace in our case) related and
1684 induced; the inferior wouldn't see them if it wasn't being
1685 traced. Hence, we should never pass them to the inferior, even
1686 when set to pass state. Since this corner case isn't handled by
1687 infrun.c when proceeding with a signal, for consistency, neither
1688 do we handle it here (or elsewhere in the file we check for
1689 signal pass state). Normally SIGTRAP isn't set to pass state, so
1690 this is really a corner case. */
1692 if (lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
1693 signo
= TARGET_SIGNAL_0
; /* a pending ptrace event, not a real signal. */
1694 else if (lp
->status
)
1695 signo
= target_signal_from_host (WSTOPSIG (lp
->status
));
1696 else if (non_stop
&& !is_executing (lp
->ptid
))
1698 struct thread_info
*tp
= find_thread_ptid (lp
->ptid
);
1699 signo
= tp
->stop_signal
;
1703 struct target_waitstatus last
;
1706 get_last_target_status (&last_ptid
, &last
);
1708 if (GET_LWP (lp
->ptid
) == GET_LWP (last_ptid
))
1710 struct thread_info
*tp
= find_thread_ptid (lp
->ptid
);
1711 signo
= tp
->stop_signal
;
1717 if (signo
== TARGET_SIGNAL_0
)
1719 if (debug_linux_nat
)
1720 fprintf_unfiltered (gdb_stdlog
,
1721 "GPT: lwp %s has no pending signal\n",
1722 target_pid_to_str (lp
->ptid
));
1724 else if (!signal_pass_state (signo
))
1726 if (debug_linux_nat
)
1727 fprintf_unfiltered (gdb_stdlog
, "\
1728 GPT: lwp %s had signal %s, but it is in no pass state\n",
1729 target_pid_to_str (lp
->ptid
),
1730 target_signal_to_string (signo
));
1734 *status
= W_STOPCODE (target_signal_to_host (signo
));
1736 if (debug_linux_nat
)
1737 fprintf_unfiltered (gdb_stdlog
,
1738 "GPT: lwp %s has pending signal %s\n",
1739 target_pid_to_str (lp
->ptid
),
1740 target_signal_to_string (signo
));
1747 detach_callback (struct lwp_info
*lp
, void *data
)
1749 gdb_assert (lp
->status
== 0 || WIFSTOPPED (lp
->status
));
1751 if (debug_linux_nat
&& lp
->status
)
1752 fprintf_unfiltered (gdb_stdlog
, "DC: Pending %s for %s on detach.\n",
1753 strsignal (WSTOPSIG (lp
->status
)),
1754 target_pid_to_str (lp
->ptid
));
1756 /* If there is a pending SIGSTOP, get rid of it. */
1759 if (debug_linux_nat
)
1760 fprintf_unfiltered (gdb_stdlog
,
1761 "DC: Sending SIGCONT to %s\n",
1762 target_pid_to_str (lp
->ptid
));
1764 kill_lwp (GET_LWP (lp
->ptid
), SIGCONT
);
1768 /* We don't actually detach from the LWP that has an id equal to the
1769 overall process id just yet. */
1770 if (GET_LWP (lp
->ptid
) != GET_PID (lp
->ptid
))
1774 /* Pass on any pending signal for this LWP. */
1775 get_pending_status (lp
, &status
);
1778 if (ptrace (PTRACE_DETACH
, GET_LWP (lp
->ptid
), 0,
1779 WSTOPSIG (status
)) < 0)
1780 error (_("Can't detach %s: %s"), target_pid_to_str (lp
->ptid
),
1781 safe_strerror (errno
));
1783 if (debug_linux_nat
)
1784 fprintf_unfiltered (gdb_stdlog
,
1785 "PTRACE_DETACH (%s, %s, 0) (OK)\n",
1786 target_pid_to_str (lp
->ptid
),
1787 strsignal (WSTOPSIG (status
)));
1789 delete_lwp (lp
->ptid
);
1796 linux_nat_detach (struct target_ops
*ops
, char *args
, int from_tty
)
1800 enum target_signal sig
;
1801 struct lwp_info
*main_lwp
;
1803 pid
= GET_PID (inferior_ptid
);
1805 if (target_can_async_p ())
1806 linux_nat_async (NULL
, 0);
1808 /* Stop all threads before detaching. ptrace requires that the
1809 thread is stopped to sucessfully detach. */
1810 iterate_over_lwps (pid_to_ptid (pid
), stop_callback
, NULL
);
1811 /* ... and wait until all of them have reported back that
1812 they're no longer running. */
1813 iterate_over_lwps (pid_to_ptid (pid
), stop_wait_callback
, NULL
);
1815 iterate_over_lwps (pid_to_ptid (pid
), detach_callback
, NULL
);
1817 /* Only the initial process should be left right now. */
1818 gdb_assert (num_lwps (GET_PID (inferior_ptid
)) == 1);
1820 main_lwp
= find_lwp_pid (pid_to_ptid (pid
));
1822 /* Pass on any pending signal for the last LWP. */
1823 if ((args
== NULL
|| *args
== '\0')
1824 && get_pending_status (main_lwp
, &status
) != -1
1825 && WIFSTOPPED (status
))
1827 /* Put the signal number in ARGS so that inf_ptrace_detach will
1828 pass it along with PTRACE_DETACH. */
1830 sprintf (args
, "%d", (int) WSTOPSIG (status
));
1831 fprintf_unfiltered (gdb_stdlog
,
1832 "LND: Sending signal %s to %s\n",
1834 target_pid_to_str (main_lwp
->ptid
));
1837 delete_lwp (main_lwp
->ptid
);
1839 if (forks_exist_p ())
1841 /* Multi-fork case. The current inferior_ptid is being detached
1842 from, but there are other viable forks to debug. Detach from
1843 the current fork, and context-switch to the first
1845 linux_fork_detach (args
, from_tty
);
1847 if (non_stop
&& target_can_async_p ())
1848 target_async (inferior_event_handler
, 0);
1851 linux_ops
->to_detach (ops
, args
, from_tty
);
1857 resume_callback (struct lwp_info
*lp
, void *data
)
1859 struct inferior
*inf
= find_inferior_pid (GET_PID (lp
->ptid
));
1861 if (lp
->stopped
&& inf
->vfork_child
!= NULL
)
1863 if (debug_linux_nat
)
1864 fprintf_unfiltered (gdb_stdlog
,
1865 "RC: Not resuming %s (vfork parent)\n",
1866 target_pid_to_str (lp
->ptid
));
1868 else if (lp
->stopped
&& lp
->status
== 0)
1870 if (debug_linux_nat
)
1871 fprintf_unfiltered (gdb_stdlog
,
1872 "RC: PTRACE_CONT %s, 0, 0 (resuming sibling)\n",
1873 target_pid_to_str (lp
->ptid
));
1875 linux_ops
->to_resume (linux_ops
,
1876 pid_to_ptid (GET_LWP (lp
->ptid
)),
1877 0, TARGET_SIGNAL_0
);
1878 if (debug_linux_nat
)
1879 fprintf_unfiltered (gdb_stdlog
,
1880 "RC: PTRACE_CONT %s, 0, 0 (resume sibling)\n",
1881 target_pid_to_str (lp
->ptid
));
1884 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
1886 else if (lp
->stopped
&& debug_linux_nat
)
1887 fprintf_unfiltered (gdb_stdlog
, "RC: Not resuming sibling %s (has pending)\n",
1888 target_pid_to_str (lp
->ptid
));
1889 else if (debug_linux_nat
)
1890 fprintf_unfiltered (gdb_stdlog
, "RC: Not resuming sibling %s (not stopped)\n",
1891 target_pid_to_str (lp
->ptid
));
1897 resume_clear_callback (struct lwp_info
*lp
, void *data
)
1904 resume_set_callback (struct lwp_info
*lp
, void *data
)
1911 linux_nat_resume (struct target_ops
*ops
,
1912 ptid_t ptid
, int step
, enum target_signal signo
)
1915 struct lwp_info
*lp
;
1918 if (debug_linux_nat
)
1919 fprintf_unfiltered (gdb_stdlog
,
1920 "LLR: Preparing to %s %s, %s, inferior_ptid %s\n",
1921 step
? "step" : "resume",
1922 target_pid_to_str (ptid
),
1923 signo
? strsignal (signo
) : "0",
1924 target_pid_to_str (inferior_ptid
));
1926 block_child_signals (&prev_mask
);
1928 /* A specific PTID means `step only this process id'. */
1929 resume_many
= (ptid_equal (minus_one_ptid
, ptid
)
1930 || ptid_is_pid (ptid
));
1934 /* Mark the lwps we're resuming as resumed. */
1935 iterate_over_lwps (minus_one_ptid
, resume_clear_callback
, NULL
);
1936 iterate_over_lwps (ptid
, resume_set_callback
, NULL
);
1939 iterate_over_lwps (minus_one_ptid
, resume_set_callback
, NULL
);
1941 /* See if it's the current inferior that should be handled
1944 lp
= find_lwp_pid (inferior_ptid
);
1946 lp
= find_lwp_pid (ptid
);
1947 gdb_assert (lp
!= NULL
);
1949 /* Remember if we're stepping. */
1952 /* If we have a pending wait status for this thread, there is no
1953 point in resuming the process. But first make sure that
1954 linux_nat_wait won't preemptively handle the event - we
1955 should never take this short-circuit if we are going to
1956 leave LP running, since we have skipped resuming all the
1957 other threads. This bit of code needs to be synchronized
1958 with linux_nat_wait. */
1960 if (lp
->status
&& WIFSTOPPED (lp
->status
))
1963 struct inferior
*inf
;
1965 inf
= find_inferior_pid (ptid_get_pid (lp
->ptid
));
1967 saved_signo
= target_signal_from_host (WSTOPSIG (lp
->status
));
1969 /* Defer to common code if we're gaining control of the
1971 if (inf
->stop_soon
== NO_STOP_QUIETLY
1972 && signal_stop_state (saved_signo
) == 0
1973 && signal_print_state (saved_signo
) == 0
1974 && signal_pass_state (saved_signo
) == 1)
1976 if (debug_linux_nat
)
1977 fprintf_unfiltered (gdb_stdlog
,
1978 "LLR: Not short circuiting for ignored "
1979 "status 0x%x\n", lp
->status
);
1981 /* FIXME: What should we do if we are supposed to continue
1982 this thread with a signal? */
1983 gdb_assert (signo
== TARGET_SIGNAL_0
);
1984 signo
= saved_signo
;
1989 if (lp
->status
|| lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
1991 /* FIXME: What should we do if we are supposed to continue
1992 this thread with a signal? */
1993 gdb_assert (signo
== TARGET_SIGNAL_0
);
1995 if (debug_linux_nat
)
1996 fprintf_unfiltered (gdb_stdlog
,
1997 "LLR: Short circuiting for status 0x%x\n",
2000 restore_child_signals_mask (&prev_mask
);
2001 if (target_can_async_p ())
2003 target_async (inferior_event_handler
, 0);
2004 /* Tell the event loop we have something to process. */
2010 /* Mark LWP as not stopped to prevent it from being continued by
2015 iterate_over_lwps (ptid
, resume_callback
, NULL
);
2017 /* Convert to something the lower layer understands. */
2018 ptid
= pid_to_ptid (GET_LWP (lp
->ptid
));
2020 linux_ops
->to_resume (linux_ops
, ptid
, step
, signo
);
2021 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
2023 if (debug_linux_nat
)
2024 fprintf_unfiltered (gdb_stdlog
,
2025 "LLR: %s %s, %s (resume event thread)\n",
2026 step
? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
2027 target_pid_to_str (ptid
),
2028 signo
? strsignal (signo
) : "0");
2030 restore_child_signals_mask (&prev_mask
);
2031 if (target_can_async_p ())
2032 target_async (inferior_event_handler
, 0);
2035 /* Issue kill to specified lwp. */
2037 static int tkill_failed
;
2040 kill_lwp (int lwpid
, int signo
)
2044 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2045 fails, then we are not using nptl threads and we should be using kill. */
2047 #ifdef HAVE_TKILL_SYSCALL
2050 int ret
= syscall (__NR_tkill
, lwpid
, signo
);
2051 if (errno
!= ENOSYS
)
2058 return kill (lwpid
, signo
);
2061 /* Handle a GNU/Linux syscall trap wait response. If we see a syscall
2062 event, check if the core is interested in it: if not, ignore the
2063 event, and keep waiting; otherwise, we need to toggle the LWP's
2064 syscall entry/exit status, since the ptrace event itself doesn't
2065 indicate it, and report the trap to higher layers. */
2068 linux_handle_syscall_trap (struct lwp_info
*lp
, int stopping
)
2070 struct target_waitstatus
*ourstatus
= &lp
->waitstatus
;
2071 struct gdbarch
*gdbarch
= target_thread_architecture (lp
->ptid
);
2072 int syscall_number
= (int) gdbarch_get_syscall_number (gdbarch
, lp
->ptid
);
2076 /* If we're stopping threads, there's a SIGSTOP pending, which
2077 makes it so that the LWP reports an immediate syscall return,
2078 followed by the SIGSTOP. Skip seeing that "return" using
2079 PTRACE_CONT directly, and let stop_wait_callback collect the
2080 SIGSTOP. Later when the thread is resumed, a new syscall
2081 entry event. If we didn't do this (and returned 0), we'd
2082 leave a syscall entry pending, and our caller, by using
2083 PTRACE_CONT to collect the SIGSTOP, skips the syscall return
2084 itself. Later, when the user re-resumes this LWP, we'd see
2085 another syscall entry event and we'd mistake it for a return.
2087 If stop_wait_callback didn't force the SIGSTOP out of the LWP
2088 (leaving immediately with LWP->signalled set, without issuing
2089 a PTRACE_CONT), it would still be problematic to leave this
2090 syscall enter pending, as later when the thread is resumed,
2091 it would then see the same syscall exit mentioned above,
2092 followed by the delayed SIGSTOP, while the syscall didn't
2093 actually get to execute. It seems it would be even more
2094 confusing to the user. */
2096 if (debug_linux_nat
)
2097 fprintf_unfiltered (gdb_stdlog
,
2098 "LHST: ignoring syscall %d "
2099 "for LWP %ld (stopping threads), "
2100 "resuming with PTRACE_CONT for SIGSTOP\n",
2102 GET_LWP (lp
->ptid
));
2104 lp
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2105 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2109 if (catch_syscall_enabled ())
2111 /* Always update the entry/return state, even if this particular
2112 syscall isn't interesting to the core now. In async mode,
2113 the user could install a new catchpoint for this syscall
2114 between syscall enter/return, and we'll need to know to
2115 report a syscall return if that happens. */
2116 lp
->syscall_state
= (lp
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2117 ? TARGET_WAITKIND_SYSCALL_RETURN
2118 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2120 if (catching_syscall_number (syscall_number
))
2122 /* Alright, an event to report. */
2123 ourstatus
->kind
= lp
->syscall_state
;
2124 ourstatus
->value
.syscall_number
= syscall_number
;
2126 if (debug_linux_nat
)
2127 fprintf_unfiltered (gdb_stdlog
,
2128 "LHST: stopping for %s of syscall %d"
2130 lp
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2131 ? "entry" : "return",
2133 GET_LWP (lp
->ptid
));
2137 if (debug_linux_nat
)
2138 fprintf_unfiltered (gdb_stdlog
,
2139 "LHST: ignoring %s of syscall %d "
2141 lp
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2142 ? "entry" : "return",
2144 GET_LWP (lp
->ptid
));
2148 /* If we had been syscall tracing, and hence used PT_SYSCALL
2149 before on this LWP, it could happen that the user removes all
2150 syscall catchpoints before we get to process this event.
2151 There are two noteworthy issues here:
2153 - When stopped at a syscall entry event, resuming with
2154 PT_STEP still resumes executing the syscall and reports a
2157 - Only PT_SYSCALL catches syscall enters. If we last
2158 single-stepped this thread, then this event can't be a
2159 syscall enter. If we last single-stepped this thread, this
2160 has to be a syscall exit.
2162 The points above mean that the next resume, be it PT_STEP or
2163 PT_CONTINUE, can not trigger a syscall trace event. */
2164 if (debug_linux_nat
)
2165 fprintf_unfiltered (gdb_stdlog
,
2166 "LHST: caught syscall event with no syscall catchpoints."
2167 " %d for LWP %ld, ignoring\n",
2169 GET_LWP (lp
->ptid
));
2170 lp
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2173 /* The core isn't interested in this event. For efficiency, avoid
2174 stopping all threads only to have the core resume them all again.
2175 Since we're not stopping threads, if we're still syscall tracing
2176 and not stepping, we can't use PTRACE_CONT here, as we'd miss any
2177 subsequent syscall. Simply resume using the inf-ptrace layer,
2178 which knows when to use PT_SYSCALL or PT_CONTINUE. */
2180 /* Note that gdbarch_get_syscall_number may access registers, hence
2182 registers_changed ();
2183 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
2184 lp
->step
, TARGET_SIGNAL_0
);
2188 /* Handle a GNU/Linux extended wait response. If we see a clone
2189 event, we need to add the new LWP to our list (and not report the
2190 trap to higher layers). This function returns non-zero if the
2191 event should be ignored and we should wait again. If STOPPING is
2192 true, the new LWP remains stopped, otherwise it is continued. */
2195 linux_handle_extended_wait (struct lwp_info
*lp
, int status
,
2198 int pid
= GET_LWP (lp
->ptid
);
2199 struct target_waitstatus
*ourstatus
= &lp
->waitstatus
;
2200 struct lwp_info
*new_lp
= NULL
;
2201 int event
= status
>> 16;
2203 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
2204 || event
== PTRACE_EVENT_CLONE
)
2206 unsigned long new_pid
;
2209 ptrace (PTRACE_GETEVENTMSG
, pid
, 0, &new_pid
);
2211 /* If we haven't already seen the new PID stop, wait for it now. */
2212 if (! pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
2214 /* The new child has a pending SIGSTOP. We can't affect it until it
2215 hits the SIGSTOP, but we're already attached. */
2216 ret
= my_waitpid (new_pid
, &status
,
2217 (event
== PTRACE_EVENT_CLONE
) ? __WCLONE
: 0);
2219 perror_with_name (_("waiting for new child"));
2220 else if (ret
!= new_pid
)
2221 internal_error (__FILE__
, __LINE__
,
2222 _("wait returned unexpected PID %d"), ret
);
2223 else if (!WIFSTOPPED (status
))
2224 internal_error (__FILE__
, __LINE__
,
2225 _("wait returned unexpected status 0x%x"), status
);
2228 ourstatus
->value
.related_pid
= ptid_build (new_pid
, new_pid
, 0);
2230 if (event
== PTRACE_EVENT_FORK
2231 && linux_fork_checkpointing_p (GET_PID (lp
->ptid
)))
2233 struct fork_info
*fp
;
2235 /* Handle checkpointing by linux-fork.c here as a special
2236 case. We don't want the follow-fork-mode or 'catch fork'
2237 to interfere with this. */
2239 /* This won't actually modify the breakpoint list, but will
2240 physically remove the breakpoints from the child. */
2241 detach_breakpoints (new_pid
);
2243 /* Retain child fork in ptrace (stopped) state. */
2244 fp
= find_fork_pid (new_pid
);
2246 fp
= add_fork (new_pid
);
2248 /* Report as spurious, so that infrun doesn't want to follow
2249 this fork. We're actually doing an infcall in
2251 ourstatus
->kind
= TARGET_WAITKIND_SPURIOUS
;
2252 linux_enable_event_reporting (pid_to_ptid (new_pid
));
2254 /* Report the stop to the core. */
2258 if (event
== PTRACE_EVENT_FORK
)
2259 ourstatus
->kind
= TARGET_WAITKIND_FORKED
;
2260 else if (event
== PTRACE_EVENT_VFORK
)
2261 ourstatus
->kind
= TARGET_WAITKIND_VFORKED
;
2264 struct cleanup
*old_chain
;
2266 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2267 new_lp
= add_lwp (BUILD_LWP (new_pid
, GET_PID (lp
->ptid
)));
2269 new_lp
->stopped
= 1;
2271 if (WSTOPSIG (status
) != SIGSTOP
)
2273 /* This can happen if someone starts sending signals to
2274 the new thread before it gets a chance to run, which
2275 have a lower number than SIGSTOP (e.g. SIGUSR1).
2276 This is an unlikely case, and harder to handle for
2277 fork / vfork than for clone, so we do not try - but
2278 we handle it for clone events here. We'll send
2279 the other signal on to the thread below. */
2281 new_lp
->signalled
= 1;
2288 /* Add the new thread to GDB's lists as soon as possible
2291 1) the frontend doesn't have to wait for a stop to
2294 2) we tag it with the correct running state. */
2296 /* If the thread_db layer is active, let it know about
2297 this new thread, and add it to GDB's list. */
2298 if (!thread_db_attach_lwp (new_lp
->ptid
))
2300 /* We're not using thread_db. Add it to GDB's
2302 target_post_attach (GET_LWP (new_lp
->ptid
));
2303 add_thread (new_lp
->ptid
);
2308 set_running (new_lp
->ptid
, 1);
2309 set_executing (new_lp
->ptid
, 1);
2313 /* Note the need to use the low target ops to resume, to
2314 handle resuming with PT_SYSCALL if we have syscall
2320 new_lp
->stopped
= 0;
2321 new_lp
->resumed
= 1;
2324 ? target_signal_from_host (WSTOPSIG (status
))
2327 linux_ops
->to_resume (linux_ops
, pid_to_ptid (new_pid
),
2331 if (debug_linux_nat
)
2332 fprintf_unfiltered (gdb_stdlog
,
2333 "LHEW: Got clone event from LWP %ld, resuming\n",
2334 GET_LWP (lp
->ptid
));
2335 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
2336 0, TARGET_SIGNAL_0
);
2344 if (event
== PTRACE_EVENT_EXEC
)
2346 if (debug_linux_nat
)
2347 fprintf_unfiltered (gdb_stdlog
,
2348 "LHEW: Got exec event from LWP %ld\n",
2349 GET_LWP (lp
->ptid
));
2351 ourstatus
->kind
= TARGET_WAITKIND_EXECD
;
2352 ourstatus
->value
.execd_pathname
2353 = xstrdup (linux_child_pid_to_exec_file (pid
));
2358 if (event
== PTRACE_EVENT_VFORK_DONE
)
2360 if (current_inferior ()->waiting_for_vfork_done
)
2362 if (debug_linux_nat
)
2363 fprintf_unfiltered (gdb_stdlog
, "\
2364 LHEW: Got expected PTRACE_EVENT_VFORK_DONE from LWP %ld: stopping\n",
2365 GET_LWP (lp
->ptid
));
2367 ourstatus
->kind
= TARGET_WAITKIND_VFORK_DONE
;
2371 if (debug_linux_nat
)
2372 fprintf_unfiltered (gdb_stdlog
, "\
2373 LHEW: Got PTRACE_EVENT_VFORK_DONE from LWP %ld: resuming\n",
2374 GET_LWP (lp
->ptid
));
2375 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2379 internal_error (__FILE__
, __LINE__
,
2380 _("unknown ptrace event %d"), event
);
2383 /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has
2387 wait_lwp (struct lwp_info
*lp
)
2391 int thread_dead
= 0;
2393 gdb_assert (!lp
->stopped
);
2394 gdb_assert (lp
->status
== 0);
2396 pid
= my_waitpid (GET_LWP (lp
->ptid
), &status
, 0);
2397 if (pid
== -1 && errno
== ECHILD
)
2399 pid
= my_waitpid (GET_LWP (lp
->ptid
), &status
, __WCLONE
);
2400 if (pid
== -1 && errno
== ECHILD
)
2402 /* The thread has previously exited. We need to delete it
2403 now because, for some vendor 2.4 kernels with NPTL
2404 support backported, there won't be an exit event unless
2405 it is the main thread. 2.6 kernels will report an exit
2406 event for each thread that exits, as expected. */
2408 if (debug_linux_nat
)
2409 fprintf_unfiltered (gdb_stdlog
, "WL: %s vanished.\n",
2410 target_pid_to_str (lp
->ptid
));
2416 gdb_assert (pid
== GET_LWP (lp
->ptid
));
2418 if (debug_linux_nat
)
2420 fprintf_unfiltered (gdb_stdlog
,
2421 "WL: waitpid %s received %s\n",
2422 target_pid_to_str (lp
->ptid
),
2423 status_to_str (status
));
2427 /* Check if the thread has exited. */
2428 if (WIFEXITED (status
) || WIFSIGNALED (status
))
2431 if (debug_linux_nat
)
2432 fprintf_unfiltered (gdb_stdlog
, "WL: %s exited.\n",
2433 target_pid_to_str (lp
->ptid
));
2442 gdb_assert (WIFSTOPPED (status
));
2444 /* Handle GNU/Linux's syscall SIGTRAPs. */
2445 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SYSCALL_SIGTRAP
)
2447 /* No longer need the sysgood bit. The ptrace event ends up
2448 recorded in lp->waitstatus if we care for it. We can carry
2449 on handling the event like a regular SIGTRAP from here
2451 status
= W_STOPCODE (SIGTRAP
);
2452 if (linux_handle_syscall_trap (lp
, 1))
2453 return wait_lwp (lp
);
2456 /* Handle GNU/Linux's extended waitstatus for trace events. */
2457 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
2459 if (debug_linux_nat
)
2460 fprintf_unfiltered (gdb_stdlog
,
2461 "WL: Handling extended status 0x%06x\n",
2463 if (linux_handle_extended_wait (lp
, status
, 1))
2464 return wait_lwp (lp
);
2470 /* Save the most recent siginfo for LP. This is currently only called
2471 for SIGTRAP; some ports use the si_addr field for
2472 target_stopped_data_address. In the future, it may also be used to
2473 restore the siginfo of requeued signals. */
2476 save_siginfo (struct lwp_info
*lp
)
2479 ptrace (PTRACE_GETSIGINFO
, GET_LWP (lp
->ptid
),
2480 (PTRACE_TYPE_ARG3
) 0, &lp
->siginfo
);
2483 memset (&lp
->siginfo
, 0, sizeof (lp
->siginfo
));
2486 /* Send a SIGSTOP to LP. */
2489 stop_callback (struct lwp_info
*lp
, void *data
)
2491 if (!lp
->stopped
&& !lp
->signalled
)
2495 if (debug_linux_nat
)
2497 fprintf_unfiltered (gdb_stdlog
,
2498 "SC: kill %s **<SIGSTOP>**\n",
2499 target_pid_to_str (lp
->ptid
));
2502 ret
= kill_lwp (GET_LWP (lp
->ptid
), SIGSTOP
);
2503 if (debug_linux_nat
)
2505 fprintf_unfiltered (gdb_stdlog
,
2506 "SC: lwp kill %d %s\n",
2508 errno
? safe_strerror (errno
) : "ERRNO-OK");
2512 gdb_assert (lp
->status
== 0);
2518 /* Return non-zero if LWP PID has a pending SIGINT. */
2521 linux_nat_has_pending_sigint (int pid
)
2523 sigset_t pending
, blocked
, ignored
;
2526 linux_proc_pending_signals (pid
, &pending
, &blocked
, &ignored
);
2528 if (sigismember (&pending
, SIGINT
)
2529 && !sigismember (&ignored
, SIGINT
))
2535 /* Set a flag in LP indicating that we should ignore its next SIGINT. */
2538 set_ignore_sigint (struct lwp_info
*lp
, void *data
)
2540 /* If a thread has a pending SIGINT, consume it; otherwise, set a
2541 flag to consume the next one. */
2542 if (lp
->stopped
&& lp
->status
!= 0 && WIFSTOPPED (lp
->status
)
2543 && WSTOPSIG (lp
->status
) == SIGINT
)
2546 lp
->ignore_sigint
= 1;
2551 /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag.
2552 This function is called after we know the LWP has stopped; if the LWP
2553 stopped before the expected SIGINT was delivered, then it will never have
2554 arrived. Also, if the signal was delivered to a shared queue and consumed
2555 by a different thread, it will never be delivered to this LWP. */
2558 maybe_clear_ignore_sigint (struct lwp_info
*lp
)
2560 if (!lp
->ignore_sigint
)
2563 if (!linux_nat_has_pending_sigint (GET_LWP (lp
->ptid
)))
2565 if (debug_linux_nat
)
2566 fprintf_unfiltered (gdb_stdlog
,
2567 "MCIS: Clearing bogus flag for %s\n",
2568 target_pid_to_str (lp
->ptid
));
2569 lp
->ignore_sigint
= 0;
2573 /* Wait until LP is stopped. */
2576 stop_wait_callback (struct lwp_info
*lp
, void *data
)
2578 struct inferior
*inf
= find_inferior_pid (GET_PID (lp
->ptid
));
2580 /* If this is a vfork parent, bail out, it is not going to report
2581 any SIGSTOP until the vfork is done with. */
2582 if (inf
->vfork_child
!= NULL
)
2589 status
= wait_lwp (lp
);
2593 if (lp
->ignore_sigint
&& WIFSTOPPED (status
)
2594 && WSTOPSIG (status
) == SIGINT
)
2596 lp
->ignore_sigint
= 0;
2599 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2600 if (debug_linux_nat
)
2601 fprintf_unfiltered (gdb_stdlog
,
2602 "PTRACE_CONT %s, 0, 0 (%s) (discarding SIGINT)\n",
2603 target_pid_to_str (lp
->ptid
),
2604 errno
? safe_strerror (errno
) : "OK");
2606 return stop_wait_callback (lp
, NULL
);
2609 maybe_clear_ignore_sigint (lp
);
2611 if (WSTOPSIG (status
) != SIGSTOP
)
2613 if (WSTOPSIG (status
) == SIGTRAP
)
2615 /* If a LWP other than the LWP that we're reporting an
2616 event for has hit a GDB breakpoint (as opposed to
2617 some random trap signal), then just arrange for it to
2618 hit it again later. We don't keep the SIGTRAP status
2619 and don't forward the SIGTRAP signal to the LWP. We
2620 will handle the current event, eventually we will
2621 resume all LWPs, and this one will get its breakpoint
2624 If we do not do this, then we run the risk that the
2625 user will delete or disable the breakpoint, but the
2626 thread will have already tripped on it. */
2628 /* Save the trap's siginfo in case we need it later. */
2631 /* Now resume this LWP and get the SIGSTOP event. */
2633 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2634 if (debug_linux_nat
)
2636 fprintf_unfiltered (gdb_stdlog
,
2637 "PTRACE_CONT %s, 0, 0 (%s)\n",
2638 target_pid_to_str (lp
->ptid
),
2639 errno
? safe_strerror (errno
) : "OK");
2641 fprintf_unfiltered (gdb_stdlog
,
2642 "SWC: Candidate SIGTRAP event in %s\n",
2643 target_pid_to_str (lp
->ptid
));
2645 /* Hold this event/waitstatus while we check to see if
2646 there are any more (we still want to get that SIGSTOP). */
2647 stop_wait_callback (lp
, NULL
);
2649 /* Hold the SIGTRAP for handling by linux_nat_wait. If
2650 there's another event, throw it back into the
2654 if (debug_linux_nat
)
2655 fprintf_unfiltered (gdb_stdlog
,
2656 "SWC: kill %s, %s\n",
2657 target_pid_to_str (lp
->ptid
),
2658 status_to_str ((int) status
));
2659 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (lp
->status
));
2662 /* Save the sigtrap event. */
2663 lp
->status
= status
;
2668 /* The thread was stopped with a signal other than
2669 SIGSTOP, and didn't accidentally trip a breakpoint. */
2671 if (debug_linux_nat
)
2673 fprintf_unfiltered (gdb_stdlog
,
2674 "SWC: Pending event %s in %s\n",
2675 status_to_str ((int) status
),
2676 target_pid_to_str (lp
->ptid
));
2678 /* Now resume this LWP and get the SIGSTOP event. */
2680 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
2681 if (debug_linux_nat
)
2682 fprintf_unfiltered (gdb_stdlog
,
2683 "SWC: PTRACE_CONT %s, 0, 0 (%s)\n",
2684 target_pid_to_str (lp
->ptid
),
2685 errno
? safe_strerror (errno
) : "OK");
2687 /* Hold this event/waitstatus while we check to see if
2688 there are any more (we still want to get that SIGSTOP). */
2689 stop_wait_callback (lp
, NULL
);
2691 /* If the lp->status field is still empty, use it to
2692 hold this event. If not, then this event must be
2693 returned to the event queue of the LWP. */
2696 if (debug_linux_nat
)
2698 fprintf_unfiltered (gdb_stdlog
,
2699 "SWC: kill %s, %s\n",
2700 target_pid_to_str (lp
->ptid
),
2701 status_to_str ((int) status
));
2703 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (status
));
2706 lp
->status
= status
;
2712 /* We caught the SIGSTOP that we intended to catch, so
2713 there's no SIGSTOP pending. */
2722 /* Return non-zero if LP has a wait status pending. */
2725 status_callback (struct lwp_info
*lp
, void *data
)
2727 /* Only report a pending wait status if we pretend that this has
2728 indeed been resumed. */
2732 if (lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
2734 /* A ptrace event, like PTRACE_FORK|VFORK|EXEC, syscall event,
2735 or a a pending process exit. Note that `W_EXITCODE(0,0) ==
2736 0', so a clean process exit can not be stored pending in
2737 lp->status, it is indistinguishable from
2738 no-pending-status. */
2742 if (lp
->status
!= 0)
2748 /* Return non-zero if LP isn't stopped. */
2751 running_callback (struct lwp_info
*lp
, void *data
)
2753 return (lp
->stopped
== 0 || (lp
->status
!= 0 && lp
->resumed
));
2756 /* Count the LWP's that have had events. */
2759 count_events_callback (struct lwp_info
*lp
, void *data
)
2763 gdb_assert (count
!= NULL
);
2765 /* Count only resumed LWPs that have a SIGTRAP event pending. */
2766 if (lp
->status
!= 0 && lp
->resumed
2767 && WIFSTOPPED (lp
->status
) && WSTOPSIG (lp
->status
) == SIGTRAP
)
2773 /* Select the LWP (if any) that is currently being single-stepped. */
2776 select_singlestep_lwp_callback (struct lwp_info
*lp
, void *data
)
2778 if (lp
->step
&& lp
->status
!= 0)
2784 /* Select the Nth LWP that has had a SIGTRAP event. */
2787 select_event_lwp_callback (struct lwp_info
*lp
, void *data
)
2789 int *selector
= data
;
2791 gdb_assert (selector
!= NULL
);
2793 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2794 if (lp
->status
!= 0 && lp
->resumed
2795 && WIFSTOPPED (lp
->status
) && WSTOPSIG (lp
->status
) == SIGTRAP
)
2796 if ((*selector
)-- == 0)
2803 cancel_breakpoint (struct lwp_info
*lp
)
2805 /* Arrange for a breakpoint to be hit again later. We don't keep
2806 the SIGTRAP status and don't forward the SIGTRAP signal to the
2807 LWP. We will handle the current event, eventually we will resume
2808 this LWP, and this breakpoint will trap again.
2810 If we do not do this, then we run the risk that the user will
2811 delete or disable the breakpoint, but the LWP will have already
2814 struct regcache
*regcache
= get_thread_regcache (lp
->ptid
);
2815 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2818 pc
= regcache_read_pc (regcache
) - gdbarch_decr_pc_after_break (gdbarch
);
2819 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
2821 if (debug_linux_nat
)
2822 fprintf_unfiltered (gdb_stdlog
,
2823 "CB: Push back breakpoint for %s\n",
2824 target_pid_to_str (lp
->ptid
));
2826 /* Back up the PC if necessary. */
2827 if (gdbarch_decr_pc_after_break (gdbarch
))
2828 regcache_write_pc (regcache
, pc
);
2836 cancel_breakpoints_callback (struct lwp_info
*lp
, void *data
)
2838 struct lwp_info
*event_lp
= data
;
2840 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
2844 /* If a LWP other than the LWP that we're reporting an event for has
2845 hit a GDB breakpoint (as opposed to some random trap signal),
2846 then just arrange for it to hit it again later. We don't keep
2847 the SIGTRAP status and don't forward the SIGTRAP signal to the
2848 LWP. We will handle the current event, eventually we will resume
2849 all LWPs, and this one will get its breakpoint trap again.
2851 If we do not do this, then we run the risk that the user will
2852 delete or disable the breakpoint, but the LWP will have already
2855 if (lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
2857 && WIFSTOPPED (lp
->status
) && WSTOPSIG (lp
->status
) == SIGTRAP
2858 && cancel_breakpoint (lp
))
2859 /* Throw away the SIGTRAP. */
2865 /* Select one LWP out of those that have events pending. */
2868 select_event_lwp (ptid_t filter
, struct lwp_info
**orig_lp
, int *status
)
2871 int random_selector
;
2872 struct lwp_info
*event_lp
;
2874 /* Record the wait status for the original LWP. */
2875 (*orig_lp
)->status
= *status
;
2877 /* Give preference to any LWP that is being single-stepped. */
2878 event_lp
= iterate_over_lwps (filter
,
2879 select_singlestep_lwp_callback
, NULL
);
2880 if (event_lp
!= NULL
)
2882 if (debug_linux_nat
)
2883 fprintf_unfiltered (gdb_stdlog
,
2884 "SEL: Select single-step %s\n",
2885 target_pid_to_str (event_lp
->ptid
));
2889 /* No single-stepping LWP. Select one at random, out of those
2890 which have had SIGTRAP events. */
2892 /* First see how many SIGTRAP events we have. */
2893 iterate_over_lwps (filter
, count_events_callback
, &num_events
);
2895 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
2896 random_selector
= (int)
2897 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2899 if (debug_linux_nat
&& num_events
> 1)
2900 fprintf_unfiltered (gdb_stdlog
,
2901 "SEL: Found %d SIGTRAP events, selecting #%d\n",
2902 num_events
, random_selector
);
2904 event_lp
= iterate_over_lwps (filter
,
2905 select_event_lwp_callback
,
2909 if (event_lp
!= NULL
)
2911 /* Switch the event LWP. */
2912 *orig_lp
= event_lp
;
2913 *status
= event_lp
->status
;
2916 /* Flush the wait status for the event LWP. */
2917 (*orig_lp
)->status
= 0;
2920 /* Return non-zero if LP has been resumed. */
2923 resumed_callback (struct lwp_info
*lp
, void *data
)
2928 /* Stop an active thread, verify it still exists, then resume it. */
2931 stop_and_resume_callback (struct lwp_info
*lp
, void *data
)
2933 struct lwp_info
*ptr
;
2935 if (!lp
->stopped
&& !lp
->signalled
)
2937 stop_callback (lp
, NULL
);
2938 stop_wait_callback (lp
, NULL
);
2939 /* Resume if the lwp still exists. */
2940 for (ptr
= lwp_list
; ptr
; ptr
= ptr
->next
)
2943 resume_callback (lp
, NULL
);
2944 resume_set_callback (lp
, NULL
);
2950 /* Check if we should go on and pass this event to common code.
2951 Return the affected lwp if we are, or NULL otherwise. */
2952 static struct lwp_info
*
2953 linux_nat_filter_event (int lwpid
, int status
, int options
)
2955 struct lwp_info
*lp
;
2957 lp
= find_lwp_pid (pid_to_ptid (lwpid
));
2959 /* Check for stop events reported by a process we didn't already
2960 know about - anything not already in our LWP list.
2962 If we're expecting to receive stopped processes after
2963 fork, vfork, and clone events, then we'll just add the
2964 new one to our list and go back to waiting for the event
2965 to be reported - the stopped process might be returned
2966 from waitpid before or after the event is. */
2967 if (WIFSTOPPED (status
) && !lp
)
2969 linux_record_stopped_pid (lwpid
, status
);
2973 /* Make sure we don't report an event for the exit of an LWP not in
2974 our list, i.e. not part of the current process. This can happen
2975 if we detach from a program we original forked and then it
2977 if (!WIFSTOPPED (status
) && !lp
)
2980 /* NOTE drow/2003-06-17: This code seems to be meant for debugging
2981 CLONE_PTRACE processes which do not use the thread library -
2982 otherwise we wouldn't find the new LWP this way. That doesn't
2983 currently work, and the following code is currently unreachable
2984 due to the two blocks above. If it's fixed some day, this code
2985 should be broken out into a function so that we can also pick up
2986 LWPs from the new interface. */
2989 lp
= add_lwp (BUILD_LWP (lwpid
, GET_PID (inferior_ptid
)));
2990 if (options
& __WCLONE
)
2993 gdb_assert (WIFSTOPPED (status
)
2994 && WSTOPSIG (status
) == SIGSTOP
);
2997 if (!in_thread_list (inferior_ptid
))
2999 inferior_ptid
= BUILD_LWP (GET_PID (inferior_ptid
),
3000 GET_PID (inferior_ptid
));
3001 add_thread (inferior_ptid
);
3004 add_thread (lp
->ptid
);
3007 /* Handle GNU/Linux's syscall SIGTRAPs. */
3008 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SYSCALL_SIGTRAP
)
3010 /* No longer need the sysgood bit. The ptrace event ends up
3011 recorded in lp->waitstatus if we care for it. We can carry
3012 on handling the event like a regular SIGTRAP from here
3014 status
= W_STOPCODE (SIGTRAP
);
3015 if (linux_handle_syscall_trap (lp
, 0))
3019 /* Handle GNU/Linux's extended waitstatus for trace events. */
3020 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
3022 if (debug_linux_nat
)
3023 fprintf_unfiltered (gdb_stdlog
,
3024 "LLW: Handling extended status 0x%06x\n",
3026 if (linux_handle_extended_wait (lp
, status
, 0))
3030 /* Save the trap's siginfo in case we need it later. */
3031 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
)
3034 /* Check if the thread has exited. */
3035 if ((WIFEXITED (status
) || WIFSIGNALED (status
))
3036 && num_lwps (GET_PID (lp
->ptid
)) > 1)
3038 /* If this is the main thread, we must stop all threads and verify
3039 if they are still alive. This is because in the nptl thread model
3040 on Linux 2.4, there is no signal issued for exiting LWPs
3041 other than the main thread. We only get the main thread exit
3042 signal once all child threads have already exited. If we
3043 stop all the threads and use the stop_wait_callback to check
3044 if they have exited we can determine whether this signal
3045 should be ignored or whether it means the end of the debugged
3046 application, regardless of which threading model is being
3048 if (GET_PID (lp
->ptid
) == GET_LWP (lp
->ptid
))
3051 iterate_over_lwps (pid_to_ptid (GET_PID (lp
->ptid
)),
3052 stop_and_resume_callback
, NULL
);
3055 if (debug_linux_nat
)
3056 fprintf_unfiltered (gdb_stdlog
,
3057 "LLW: %s exited.\n",
3058 target_pid_to_str (lp
->ptid
));
3060 if (num_lwps (GET_PID (lp
->ptid
)) > 1)
3062 /* If there is at least one more LWP, then the exit signal
3063 was not the end of the debugged application and should be
3070 /* Check if the current LWP has previously exited. In the nptl
3071 thread model, LWPs other than the main thread do not issue
3072 signals when they exit so we must check whenever the thread has
3073 stopped. A similar check is made in stop_wait_callback(). */
3074 if (num_lwps (GET_PID (lp
->ptid
)) > 1 && !linux_thread_alive (lp
->ptid
))
3076 ptid_t ptid
= pid_to_ptid (GET_PID (lp
->ptid
));
3078 if (debug_linux_nat
)
3079 fprintf_unfiltered (gdb_stdlog
,
3080 "LLW: %s exited.\n",
3081 target_pid_to_str (lp
->ptid
));
3085 /* Make sure there is at least one thread running. */
3086 gdb_assert (iterate_over_lwps (ptid
, running_callback
, NULL
));
3088 /* Discard the event. */
3092 /* Make sure we don't report a SIGSTOP that we sent ourselves in
3093 an attempt to stop an LWP. */
3095 && WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGSTOP
)
3097 if (debug_linux_nat
)
3098 fprintf_unfiltered (gdb_stdlog
,
3099 "LLW: Delayed SIGSTOP caught for %s.\n",
3100 target_pid_to_str (lp
->ptid
));
3102 /* This is a delayed SIGSTOP. */
3105 registers_changed ();
3107 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3108 lp
->step
, TARGET_SIGNAL_0
);
3109 if (debug_linux_nat
)
3110 fprintf_unfiltered (gdb_stdlog
,
3111 "LLW: %s %s, 0, 0 (discard SIGSTOP)\n",
3113 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3114 target_pid_to_str (lp
->ptid
));
3117 gdb_assert (lp
->resumed
);
3119 /* Discard the event. */
3123 /* Make sure we don't report a SIGINT that we have already displayed
3124 for another thread. */
3125 if (lp
->ignore_sigint
3126 && WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGINT
)
3128 if (debug_linux_nat
)
3129 fprintf_unfiltered (gdb_stdlog
,
3130 "LLW: Delayed SIGINT caught for %s.\n",
3131 target_pid_to_str (lp
->ptid
));
3133 /* This is a delayed SIGINT. */
3134 lp
->ignore_sigint
= 0;
3136 registers_changed ();
3137 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3138 lp
->step
, TARGET_SIGNAL_0
);
3139 if (debug_linux_nat
)
3140 fprintf_unfiltered (gdb_stdlog
,
3141 "LLW: %s %s, 0, 0 (discard SIGINT)\n",
3143 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3144 target_pid_to_str (lp
->ptid
));
3147 gdb_assert (lp
->resumed
);
3149 /* Discard the event. */
3153 /* An interesting event. */
3155 lp
->status
= status
;
3160 linux_nat_wait_1 (struct target_ops
*ops
,
3161 ptid_t ptid
, struct target_waitstatus
*ourstatus
,
3164 static sigset_t prev_mask
;
3165 struct lwp_info
*lp
= NULL
;
3170 if (debug_linux_nat_async
)
3171 fprintf_unfiltered (gdb_stdlog
, "LLW: enter\n");
3173 /* The first time we get here after starting a new inferior, we may
3174 not have added it to the LWP list yet - this is the earliest
3175 moment at which we know its PID. */
3176 if (ptid_is_pid (inferior_ptid
))
3178 /* Upgrade the main thread's ptid. */
3179 thread_change_ptid (inferior_ptid
,
3180 BUILD_LWP (GET_PID (inferior_ptid
),
3181 GET_PID (inferior_ptid
)));
3183 lp
= add_lwp (inferior_ptid
);
3187 /* Make sure SIGCHLD is blocked. */
3188 block_child_signals (&prev_mask
);
3190 if (ptid_equal (ptid
, minus_one_ptid
))
3192 else if (ptid_is_pid (ptid
))
3193 /* A request to wait for a specific tgid. This is not possible
3194 with waitpid, so instead, we wait for any child, and leave
3195 children we're not interested in right now with a pending
3196 status to report later. */
3199 pid
= GET_LWP (ptid
);
3205 /* Make sure there is at least one LWP that has been resumed. */
3206 gdb_assert (iterate_over_lwps (ptid
, resumed_callback
, NULL
));
3208 /* First check if there is a LWP with a wait status pending. */
3211 /* Any LWP that's been resumed will do. */
3212 lp
= iterate_over_lwps (ptid
, status_callback
, NULL
);
3215 if (debug_linux_nat
&& lp
->status
)
3216 fprintf_unfiltered (gdb_stdlog
,
3217 "LLW: Using pending wait status %s for %s.\n",
3218 status_to_str (lp
->status
),
3219 target_pid_to_str (lp
->ptid
));
3222 /* But if we don't find one, we'll have to wait, and check both
3223 cloned and uncloned processes. We start with the cloned
3225 options
= __WCLONE
| WNOHANG
;
3227 else if (is_lwp (ptid
))
3229 if (debug_linux_nat
)
3230 fprintf_unfiltered (gdb_stdlog
,
3231 "LLW: Waiting for specific LWP %s.\n",
3232 target_pid_to_str (ptid
));
3234 /* We have a specific LWP to check. */
3235 lp
= find_lwp_pid (ptid
);
3238 if (debug_linux_nat
&& lp
->status
)
3239 fprintf_unfiltered (gdb_stdlog
,
3240 "LLW: Using pending wait status %s for %s.\n",
3241 status_to_str (lp
->status
),
3242 target_pid_to_str (lp
->ptid
));
3244 /* If we have to wait, take into account whether PID is a cloned
3245 process or not. And we have to convert it to something that
3246 the layer beneath us can understand. */
3247 options
= lp
->cloned
? __WCLONE
: 0;
3248 pid
= GET_LWP (ptid
);
3250 /* We check for lp->waitstatus in addition to lp->status,
3251 because we can have pending process exits recorded in
3252 lp->status and W_EXITCODE(0,0) == 0. We should probably have
3253 an additional lp->status_p flag. */
3254 if (lp
->status
== 0 && lp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
)
3258 if (lp
&& lp
->signalled
)
3260 /* A pending SIGSTOP may interfere with the normal stream of
3261 events. In a typical case where interference is a problem,
3262 we have a SIGSTOP signal pending for LWP A while
3263 single-stepping it, encounter an event in LWP B, and take the
3264 pending SIGSTOP while trying to stop LWP A. After processing
3265 the event in LWP B, LWP A is continued, and we'll never see
3266 the SIGTRAP associated with the last time we were
3267 single-stepping LWP A. */
3269 /* Resume the thread. It should halt immediately returning the
3271 registers_changed ();
3272 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3273 lp
->step
, TARGET_SIGNAL_0
);
3274 if (debug_linux_nat
)
3275 fprintf_unfiltered (gdb_stdlog
,
3276 "LLW: %s %s, 0, 0 (expect SIGSTOP)\n",
3277 lp
->step
? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3278 target_pid_to_str (lp
->ptid
));
3280 gdb_assert (lp
->resumed
);
3282 /* Catch the pending SIGSTOP. */
3283 status
= lp
->status
;
3286 stop_wait_callback (lp
, NULL
);
3288 /* If the lp->status field isn't empty, we caught another signal
3289 while flushing the SIGSTOP. Return it back to the event
3290 queue of the LWP, as we already have an event to handle. */
3293 if (debug_linux_nat
)
3294 fprintf_unfiltered (gdb_stdlog
,
3295 "LLW: kill %s, %s\n",
3296 target_pid_to_str (lp
->ptid
),
3297 status_to_str (lp
->status
));
3298 kill_lwp (GET_LWP (lp
->ptid
), WSTOPSIG (lp
->status
));
3301 lp
->status
= status
;
3304 if (!target_can_async_p ())
3306 /* Causes SIGINT to be passed on to the attached process. */
3310 /* Translate generic target_wait options into waitpid options. */
3311 if (target_options
& TARGET_WNOHANG
)
3318 lwpid
= my_waitpid (pid
, &status
, options
);
3322 gdb_assert (pid
== -1 || lwpid
== pid
);
3324 if (debug_linux_nat
)
3326 fprintf_unfiltered (gdb_stdlog
,
3327 "LLW: waitpid %ld received %s\n",
3328 (long) lwpid
, status_to_str (status
));
3331 lp
= linux_nat_filter_event (lwpid
, status
, options
);
3334 && ptid_is_pid (ptid
)
3335 && ptid_get_pid (lp
->ptid
) != ptid_get_pid (ptid
))
3337 if (debug_linux_nat
)
3338 fprintf (stderr
, "LWP %ld got an event %06x, leaving pending.\n",
3339 ptid_get_lwp (lp
->ptid
), status
);
3341 if (WIFSTOPPED (lp
->status
))
3343 if (WSTOPSIG (lp
->status
) != SIGSTOP
)
3345 stop_callback (lp
, NULL
);
3347 /* Resume in order to collect the sigstop. */
3348 ptrace (PTRACE_CONT
, GET_LWP (lp
->ptid
), 0, 0);
3350 stop_wait_callback (lp
, NULL
);
3358 else if (WIFEXITED (status
) || WIFSIGNALED (status
))
3360 if (debug_linux_nat
)
3361 fprintf (stderr
, "Process %ld exited while stopping LWPs\n",
3362 ptid_get_lwp (lp
->ptid
));
3364 /* This was the last lwp in the process. Since
3365 events are serialized to GDB core, and we can't
3366 report this one right now, but GDB core and the
3367 other target layers will want to be notified
3368 about the exit code/signal, leave the status
3369 pending for the next time we're able to report
3372 /* Prevent trying to stop this thread again. We'll
3373 never try to resume it because it has a pending
3377 /* Dead LWP's aren't expected to reported a pending
3381 /* Store the pending event in the waitstatus as
3382 well, because W_EXITCODE(0,0) == 0. */
3383 store_waitstatus (&lp
->waitstatus
, lp
->status
);
3397 /* waitpid did return something. Restart over. */
3398 options
|= __WCLONE
;
3406 /* Alternate between checking cloned and uncloned processes. */
3407 options
^= __WCLONE
;
3409 /* And every time we have checked both:
3410 In async mode, return to event loop;
3411 In sync mode, suspend waiting for a SIGCHLD signal. */
3412 if (options
& __WCLONE
)
3414 if (target_options
& TARGET_WNOHANG
)
3416 /* No interesting event. */
3417 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3419 if (debug_linux_nat_async
)
3420 fprintf_unfiltered (gdb_stdlog
, "LLW: exit (ignore)\n");
3422 restore_child_signals_mask (&prev_mask
);
3423 return minus_one_ptid
;
3426 sigsuspend (&suspend_mask
);
3429 else if (target_options
& TARGET_WNOHANG
)
3431 /* No interesting event for PID yet. */
3432 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3434 if (debug_linux_nat_async
)
3435 fprintf_unfiltered (gdb_stdlog
, "LLW: exit (ignore)\n");
3437 restore_child_signals_mask (&prev_mask
);
3438 return minus_one_ptid
;
3441 /* We shouldn't end up here unless we want to try again. */
3442 gdb_assert (lp
== NULL
);
3445 if (!target_can_async_p ())
3446 clear_sigint_trap ();
3450 status
= lp
->status
;
3453 /* Don't report signals that GDB isn't interested in, such as
3454 signals that are neither printed nor stopped upon. Stopping all
3455 threads can be a bit time-consuming so if we want decent
3456 performance with heavily multi-threaded programs, especially when
3457 they're using a high frequency timer, we'd better avoid it if we
3460 if (WIFSTOPPED (status
))
3462 int signo
= target_signal_from_host (WSTOPSIG (status
));
3463 struct inferior
*inf
;
3465 inf
= find_inferior_pid (ptid_get_pid (lp
->ptid
));
3468 /* Defer to common code if we get a signal while
3469 single-stepping, since that may need special care, e.g. to
3470 skip the signal handler, or, if we're gaining control of the
3473 && inf
->stop_soon
== NO_STOP_QUIETLY
3474 && signal_stop_state (signo
) == 0
3475 && signal_print_state (signo
) == 0
3476 && signal_pass_state (signo
) == 1)
3478 /* FIMXE: kettenis/2001-06-06: Should we resume all threads
3479 here? It is not clear we should. GDB may not expect
3480 other threads to run. On the other hand, not resuming
3481 newly attached threads may cause an unwanted delay in
3482 getting them running. */
3483 registers_changed ();
3484 linux_ops
->to_resume (linux_ops
, pid_to_ptid (GET_LWP (lp
->ptid
)),
3486 if (debug_linux_nat
)
3487 fprintf_unfiltered (gdb_stdlog
,
3488 "LLW: %s %s, %s (preempt 'handle')\n",
3490 "PTRACE_SINGLESTEP" : "PTRACE_CONT",
3491 target_pid_to_str (lp
->ptid
),
3492 signo
? strsignal (signo
) : "0");
3499 /* Only do the below in all-stop, as we currently use SIGINT
3500 to implement target_stop (see linux_nat_stop) in
3502 if (signo
== TARGET_SIGNAL_INT
&& signal_pass_state (signo
) == 0)
3504 /* If ^C/BREAK is typed at the tty/console, SIGINT gets
3505 forwarded to the entire process group, that is, all LWPs
3506 will receive it - unless they're using CLONE_THREAD to
3507 share signals. Since we only want to report it once, we
3508 mark it as ignored for all LWPs except this one. */
3509 iterate_over_lwps (pid_to_ptid (ptid_get_pid (ptid
)),
3510 set_ignore_sigint
, NULL
);
3511 lp
->ignore_sigint
= 0;
3514 maybe_clear_ignore_sigint (lp
);
3518 /* This LWP is stopped now. */
3521 if (debug_linux_nat
)
3522 fprintf_unfiltered (gdb_stdlog
, "LLW: Candidate event %s in %s.\n",
3523 status_to_str (status
), target_pid_to_str (lp
->ptid
));
3527 /* Now stop all other LWP's ... */
3528 iterate_over_lwps (minus_one_ptid
, stop_callback
, NULL
);
3530 /* ... and wait until all of them have reported back that
3531 they're no longer running. */
3532 iterate_over_lwps (minus_one_ptid
, stop_wait_callback
, NULL
);
3534 /* If we're not waiting for a specific LWP, choose an event LWP
3535 from among those that have had events. Giving equal priority
3536 to all LWPs that have had events helps prevent
3539 select_event_lwp (ptid
, &lp
, &status
);
3542 /* Now that we've selected our final event LWP, cancel any
3543 breakpoints in other LWPs that have hit a GDB breakpoint. See
3544 the comment in cancel_breakpoints_callback to find out why. */
3545 iterate_over_lwps (minus_one_ptid
, cancel_breakpoints_callback
, lp
);
3547 if (WIFSTOPPED (status
) && WSTOPSIG (status
) == SIGTRAP
)
3549 if (debug_linux_nat
)
3550 fprintf_unfiltered (gdb_stdlog
,
3551 "LLW: trap ptid is %s.\n",
3552 target_pid_to_str (lp
->ptid
));
3555 if (lp
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3557 *ourstatus
= lp
->waitstatus
;
3558 lp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3561 store_waitstatus (ourstatus
, status
);
3563 if (debug_linux_nat_async
)
3564 fprintf_unfiltered (gdb_stdlog
, "LLW: exit\n");
3566 restore_child_signals_mask (&prev_mask
);
3571 linux_nat_wait (struct target_ops
*ops
,
3572 ptid_t ptid
, struct target_waitstatus
*ourstatus
,
3577 if (debug_linux_nat
)
3578 fprintf_unfiltered (gdb_stdlog
, "linux_nat_wait: [%s]\n", target_pid_to_str (ptid
));
3580 /* Flush the async file first. */
3581 if (target_can_async_p ())
3582 async_file_flush ();
3584 event_ptid
= linux_nat_wait_1 (ops
, ptid
, ourstatus
, target_options
);
3586 /* If we requested any event, and something came out, assume there
3587 may be more. If we requested a specific lwp or process, also
3588 assume there may be more. */
3589 if (target_can_async_p ()
3590 && (ourstatus
->kind
!= TARGET_WAITKIND_IGNORE
3591 || !ptid_equal (ptid
, minus_one_ptid
)))
3594 /* Get ready for the next event. */
3595 if (target_can_async_p ())
3596 target_async (inferior_event_handler
, 0);
3602 kill_callback (struct lwp_info
*lp
, void *data
)
3605 ptrace (PTRACE_KILL
, GET_LWP (lp
->ptid
), 0, 0);
3606 if (debug_linux_nat
)
3607 fprintf_unfiltered (gdb_stdlog
,
3608 "KC: PTRACE_KILL %s, 0, 0 (%s)\n",
3609 target_pid_to_str (lp
->ptid
),
3610 errno
? safe_strerror (errno
) : "OK");
3616 kill_wait_callback (struct lwp_info
*lp
, void *data
)
3620 /* We must make sure that there are no pending events (delayed
3621 SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current
3622 program doesn't interfere with any following debugging session. */
3624 /* For cloned processes we must check both with __WCLONE and
3625 without, since the exit status of a cloned process isn't reported
3631 pid
= my_waitpid (GET_LWP (lp
->ptid
), NULL
, __WCLONE
);
3632 if (pid
!= (pid_t
) -1)
3634 if (debug_linux_nat
)
3635 fprintf_unfiltered (gdb_stdlog
,
3636 "KWC: wait %s received unknown.\n",
3637 target_pid_to_str (lp
->ptid
));
3638 /* The Linux kernel sometimes fails to kill a thread
3639 completely after PTRACE_KILL; that goes from the stop
3640 point in do_fork out to the one in
3641 get_signal_to_deliever and waits again. So kill it
3643 kill_callback (lp
, NULL
);
3646 while (pid
== GET_LWP (lp
->ptid
));
3648 gdb_assert (pid
== -1 && errno
== ECHILD
);
3653 pid
= my_waitpid (GET_LWP (lp
->ptid
), NULL
, 0);
3654 if (pid
!= (pid_t
) -1)
3656 if (debug_linux_nat
)
3657 fprintf_unfiltered (gdb_stdlog
,
3658 "KWC: wait %s received unk.\n",
3659 target_pid_to_str (lp
->ptid
));
3660 /* See the call to kill_callback above. */
3661 kill_callback (lp
, NULL
);
3664 while (pid
== GET_LWP (lp
->ptid
));
3666 gdb_assert (pid
== -1 && errno
== ECHILD
);
3671 linux_nat_kill (struct target_ops
*ops
)
3673 struct target_waitstatus last
;
3677 /* If we're stopped while forking and we haven't followed yet,
3678 kill the other task. We need to do this first because the
3679 parent will be sleeping if this is a vfork. */
3681 get_last_target_status (&last_ptid
, &last
);
3683 if (last
.kind
== TARGET_WAITKIND_FORKED
3684 || last
.kind
== TARGET_WAITKIND_VFORKED
)
3686 ptrace (PT_KILL
, PIDGET (last
.value
.related_pid
), 0, 0);
3690 if (forks_exist_p ())
3691 linux_fork_killall ();
3694 ptid_t ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
3695 /* Stop all threads before killing them, since ptrace requires
3696 that the thread is stopped to sucessfully PTRACE_KILL. */
3697 iterate_over_lwps (ptid
, stop_callback
, NULL
);
3698 /* ... and wait until all of them have reported back that
3699 they're no longer running. */
3700 iterate_over_lwps (ptid
, stop_wait_callback
, NULL
);
3702 /* Kill all LWP's ... */
3703 iterate_over_lwps (ptid
, kill_callback
, NULL
);
3705 /* ... and wait until we've flushed all events. */
3706 iterate_over_lwps (ptid
, kill_wait_callback
, NULL
);
3709 target_mourn_inferior ();
3713 linux_nat_mourn_inferior (struct target_ops
*ops
)
3715 purge_lwp_list (ptid_get_pid (inferior_ptid
));
3717 if (! forks_exist_p ())
3718 /* Normal case, no other forks available. */
3719 linux_ops
->to_mourn_inferior (ops
);
3721 /* Multi-fork case. The current inferior_ptid has exited, but
3722 there are other viable forks to debug. Delete the exiting
3723 one and context-switch to the first available. */
3724 linux_fork_mourn_inferior ();
3727 /* Convert a native/host siginfo object, into/from the siginfo in the
3728 layout of the inferiors' architecture. */
3731 siginfo_fixup (struct siginfo
*siginfo
, gdb_byte
*inf_siginfo
, int direction
)
3735 if (linux_nat_siginfo_fixup
!= NULL
)
3736 done
= linux_nat_siginfo_fixup (siginfo
, inf_siginfo
, direction
);
3738 /* If there was no callback, or the callback didn't do anything,
3739 then just do a straight memcpy. */
3743 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
3745 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
3750 linux_xfer_siginfo (struct target_ops
*ops
, enum target_object object
,
3751 const char *annex
, gdb_byte
*readbuf
,
3752 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
3755 struct siginfo siginfo
;
3756 gdb_byte inf_siginfo
[sizeof (struct siginfo
)];
3758 gdb_assert (object
== TARGET_OBJECT_SIGNAL_INFO
);
3759 gdb_assert (readbuf
|| writebuf
);
3761 pid
= GET_LWP (inferior_ptid
);
3763 pid
= GET_PID (inferior_ptid
);
3765 if (offset
> sizeof (siginfo
))
3769 ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
);
3773 /* When GDB is built as a 64-bit application, ptrace writes into
3774 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
3775 inferior with a 64-bit GDB should look the same as debugging it
3776 with a 32-bit GDB, we need to convert it. GDB core always sees
3777 the converted layout, so any read/write will have to be done
3779 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
3781 if (offset
+ len
> sizeof (siginfo
))
3782 len
= sizeof (siginfo
) - offset
;
3784 if (readbuf
!= NULL
)
3785 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
3788 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
3790 /* Convert back to ptrace layout before flushing it out. */
3791 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
3794 ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
);
3803 linux_nat_xfer_partial (struct target_ops
*ops
, enum target_object object
,
3804 const char *annex
, gdb_byte
*readbuf
,
3805 const gdb_byte
*writebuf
,
3806 ULONGEST offset
, LONGEST len
)
3808 struct cleanup
*old_chain
;
3811 if (object
== TARGET_OBJECT_SIGNAL_INFO
)
3812 return linux_xfer_siginfo (ops
, object
, annex
, readbuf
, writebuf
,
3815 /* The target is connected but no live inferior is selected. Pass
3816 this request down to a lower stratum (e.g., the executable
3818 if (object
== TARGET_OBJECT_MEMORY
&& ptid_equal (inferior_ptid
, null_ptid
))
3821 old_chain
= save_inferior_ptid ();
3823 if (is_lwp (inferior_ptid
))
3824 inferior_ptid
= pid_to_ptid (GET_LWP (inferior_ptid
));
3826 xfer
= linux_ops
->to_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
3829 do_cleanups (old_chain
);
3834 linux_thread_alive (ptid_t ptid
)
3838 gdb_assert (is_lwp (ptid
));
3840 /* Send signal 0 instead of anything ptrace, because ptracing a
3841 running thread errors out claiming that the thread doesn't
3843 err
= kill_lwp (GET_LWP (ptid
), 0);
3845 if (debug_linux_nat
)
3846 fprintf_unfiltered (gdb_stdlog
,
3847 "LLTA: KILL(SIG0) %s (%s)\n",
3848 target_pid_to_str (ptid
),
3849 err
? safe_strerror (err
) : "OK");
3858 linux_nat_thread_alive (struct target_ops
*ops
, ptid_t ptid
)
3860 return linux_thread_alive (ptid
);
3864 linux_nat_pid_to_str (struct target_ops
*ops
, ptid_t ptid
)
3866 static char buf
[64];
3869 && (GET_PID (ptid
) != GET_LWP (ptid
)
3870 || num_lwps (GET_PID (ptid
)) > 1))
3872 snprintf (buf
, sizeof (buf
), "LWP %ld", GET_LWP (ptid
));
3876 return normal_pid_to_str (ptid
);
3879 /* Accepts an integer PID; Returns a string representing a file that
3880 can be opened to get the symbols for the child process. */
3883 linux_child_pid_to_exec_file (int pid
)
3885 char *name1
, *name2
;
3887 name1
= xmalloc (MAXPATHLEN
);
3888 name2
= xmalloc (MAXPATHLEN
);
3889 make_cleanup (xfree
, name1
);
3890 make_cleanup (xfree
, name2
);
3891 memset (name2
, 0, MAXPATHLEN
);
3893 sprintf (name1
, "/proc/%d/exe", pid
);
3894 if (readlink (name1
, name2
, MAXPATHLEN
) > 0)
3900 /* Service function for corefiles and info proc. */
3903 read_mapping (FILE *mapfile
,
3908 char *device
, long long *inode
, char *filename
)
3910 int ret
= fscanf (mapfile
, "%llx-%llx %s %llx %s %llx",
3911 addr
, endaddr
, permissions
, offset
, device
, inode
);
3914 if (ret
> 0 && ret
!= EOF
)
3916 /* Eat everything up to EOL for the filename. This will prevent
3917 weird filenames (such as one with embedded whitespace) from
3918 confusing this code. It also makes this code more robust in
3919 respect to annotations the kernel may add after the filename.
3921 Note the filename is used for informational purposes
3923 ret
+= fscanf (mapfile
, "%[^\n]\n", filename
);
3926 return (ret
!= 0 && ret
!= EOF
);
3929 /* Fills the "to_find_memory_regions" target vector. Lists the memory
3930 regions in the inferior for a corefile. */
3933 linux_nat_find_memory_regions (int (*func
) (CORE_ADDR
,
3935 int, int, int, void *), void *obfd
)
3937 int pid
= PIDGET (inferior_ptid
);
3938 char mapsfilename
[MAXPATHLEN
];
3940 long long addr
, endaddr
, size
, offset
, inode
;
3941 char permissions
[8], device
[8], filename
[MAXPATHLEN
];
3942 int read
, write
, exec
;
3944 struct cleanup
*cleanup
;
3946 /* Compose the filename for the /proc memory map, and open it. */
3947 sprintf (mapsfilename
, "/proc/%d/maps", pid
);
3948 if ((mapsfile
= fopen (mapsfilename
, "r")) == NULL
)
3949 error (_("Could not open %s."), mapsfilename
);
3950 cleanup
= make_cleanup_fclose (mapsfile
);
3953 fprintf_filtered (gdb_stdout
,
3954 "Reading memory regions from %s\n", mapsfilename
);
3956 /* Now iterate until end-of-file. */
3957 while (read_mapping (mapsfile
, &addr
, &endaddr
, &permissions
[0],
3958 &offset
, &device
[0], &inode
, &filename
[0]))
3960 size
= endaddr
- addr
;
3962 /* Get the segment's permissions. */
3963 read
= (strchr (permissions
, 'r') != 0);
3964 write
= (strchr (permissions
, 'w') != 0);
3965 exec
= (strchr (permissions
, 'x') != 0);
3969 fprintf_filtered (gdb_stdout
,
3970 "Save segment, %lld bytes at %s (%c%c%c)",
3971 size
, paddress (target_gdbarch
, addr
),
3973 write
? 'w' : ' ', exec
? 'x' : ' ');
3975 fprintf_filtered (gdb_stdout
, " for %s", filename
);
3976 fprintf_filtered (gdb_stdout
, "\n");
3979 /* Invoke the callback function to create the corefile
3981 func (addr
, size
, read
, write
, exec
, obfd
);
3983 do_cleanups (cleanup
);
3988 find_signalled_thread (struct thread_info
*info
, void *data
)
3990 if (info
->stop_signal
!= TARGET_SIGNAL_0
3991 && ptid_get_pid (info
->ptid
) == ptid_get_pid (inferior_ptid
))
3997 static enum target_signal
3998 find_stop_signal (void)
4000 struct thread_info
*info
=
4001 iterate_over_threads (find_signalled_thread
, NULL
);
4004 return info
->stop_signal
;
4006 return TARGET_SIGNAL_0
;
4009 /* Records the thread's register state for the corefile note
4013 linux_nat_do_thread_registers (bfd
*obfd
, ptid_t ptid
,
4014 char *note_data
, int *note_size
,
4015 enum target_signal stop_signal
)
4017 gdb_gregset_t gregs
;
4018 gdb_fpregset_t fpregs
;
4019 unsigned long lwp
= ptid_get_lwp (ptid
);
4020 struct gdbarch
*gdbarch
= target_gdbarch
;
4021 struct regcache
*regcache
= get_thread_arch_regcache (ptid
, gdbarch
);
4022 const struct regset
*regset
;
4024 struct cleanup
*old_chain
;
4025 struct core_regset_section
*sect_list
;
4028 old_chain
= save_inferior_ptid ();
4029 inferior_ptid
= ptid
;
4030 target_fetch_registers (regcache
, -1);
4031 do_cleanups (old_chain
);
4033 core_regset_p
= gdbarch_regset_from_core_section_p (gdbarch
);
4034 sect_list
= gdbarch_core_regset_sections (gdbarch
);
4037 && (regset
= gdbarch_regset_from_core_section (gdbarch
, ".reg",
4038 sizeof (gregs
))) != NULL
4039 && regset
->collect_regset
!= NULL
)
4040 regset
->collect_regset (regset
, regcache
, -1,
4041 &gregs
, sizeof (gregs
));
4043 fill_gregset (regcache
, &gregs
, -1);
4045 note_data
= (char *) elfcore_write_prstatus (obfd
,
4049 stop_signal
, &gregs
);
4051 /* The loop below uses the new struct core_regset_section, which stores
4052 the supported section names and sizes for the core file. Note that
4053 note PRSTATUS needs to be treated specially. But the other notes are
4054 structurally the same, so they can benefit from the new struct. */
4055 if (core_regset_p
&& sect_list
!= NULL
)
4056 while (sect_list
->sect_name
!= NULL
)
4058 /* .reg was already handled above. */
4059 if (strcmp (sect_list
->sect_name
, ".reg") == 0)
4064 regset
= gdbarch_regset_from_core_section (gdbarch
,
4065 sect_list
->sect_name
,
4067 gdb_assert (regset
&& regset
->collect_regset
);
4068 gdb_regset
= xmalloc (sect_list
->size
);
4069 regset
->collect_regset (regset
, regcache
, -1,
4070 gdb_regset
, sect_list
->size
);
4071 note_data
= (char *) elfcore_write_register_note (obfd
,
4074 sect_list
->sect_name
,
4081 /* For architectures that does not have the struct core_regset_section
4082 implemented, we use the old method. When all the architectures have
4083 the new support, the code below should be deleted. */
4087 && (regset
= gdbarch_regset_from_core_section (gdbarch
, ".reg2",
4088 sizeof (fpregs
))) != NULL
4089 && regset
->collect_regset
!= NULL
)
4090 regset
->collect_regset (regset
, regcache
, -1,
4091 &fpregs
, sizeof (fpregs
));
4093 fill_fpregset (regcache
, &fpregs
, -1);
4095 note_data
= (char *) elfcore_write_prfpreg (obfd
,
4098 &fpregs
, sizeof (fpregs
));
4104 struct linux_nat_corefile_thread_data
4110 enum target_signal stop_signal
;
4113 /* Called by gdbthread.c once per thread. Records the thread's
4114 register state for the corefile note section. */
4117 linux_nat_corefile_thread_callback (struct lwp_info
*ti
, void *data
)
4119 struct linux_nat_corefile_thread_data
*args
= data
;
4121 args
->note_data
= linux_nat_do_thread_registers (args
->obfd
,
4131 /* Enumerate spufs IDs for process PID. */
4134 iterate_over_spus (int pid
, void (*callback
) (void *, int), void *data
)
4138 struct dirent
*entry
;
4140 xsnprintf (path
, sizeof path
, "/proc/%d/fd", pid
);
4141 dir
= opendir (path
);
4146 while ((entry
= readdir (dir
)) != NULL
)
4152 fd
= atoi (entry
->d_name
);
4156 xsnprintf (path
, sizeof path
, "/proc/%d/fd/%d", pid
, fd
);
4157 if (stat (path
, &st
) != 0)
4159 if (!S_ISDIR (st
.st_mode
))
4162 if (statfs (path
, &stfs
) != 0)
4164 if (stfs
.f_type
!= SPUFS_MAGIC
)
4167 callback (data
, fd
);
4173 /* Generate corefile notes for SPU contexts. */
4175 struct linux_spu_corefile_data
4183 linux_spu_corefile_callback (void *data
, int fd
)
4185 struct linux_spu_corefile_data
*args
= data
;
4188 static const char *spu_files
[] =
4210 for (i
= 0; i
< sizeof (spu_files
) / sizeof (spu_files
[0]); i
++)
4212 char annex
[32], note_name
[32];
4216 xsnprintf (annex
, sizeof annex
, "%d/%s", fd
, spu_files
[i
]);
4217 spu_len
= target_read_alloc (¤t_target
, TARGET_OBJECT_SPU
,
4221 xsnprintf (note_name
, sizeof note_name
, "SPU/%s", annex
);
4222 args
->note_data
= elfcore_write_note (args
->obfd
, args
->note_data
,
4223 args
->note_size
, note_name
,
4224 NT_SPU
, spu_data
, spu_len
);
4231 linux_spu_make_corefile_notes (bfd
*obfd
, char *note_data
, int *note_size
)
4233 struct linux_spu_corefile_data args
;
4235 args
.note_data
= note_data
;
4236 args
.note_size
= note_size
;
4238 iterate_over_spus (PIDGET (inferior_ptid
),
4239 linux_spu_corefile_callback
, &args
);
4241 return args
.note_data
;
4244 /* Fills the "to_make_corefile_note" target vector. Builds the note
4245 section for a corefile, and returns it in a malloc buffer. */
4248 linux_nat_make_corefile_notes (bfd
*obfd
, int *note_size
)
4250 struct linux_nat_corefile_thread_data thread_args
;
4251 struct cleanup
*old_chain
;
4252 /* The variable size must be >= sizeof (prpsinfo_t.pr_fname). */
4253 char fname
[16] = { '\0' };
4254 /* The variable size must be >= sizeof (prpsinfo_t.pr_psargs). */
4255 char psargs
[80] = { '\0' };
4256 char *note_data
= NULL
;
4257 ptid_t current_ptid
= inferior_ptid
;
4258 ptid_t filter
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
4262 if (get_exec_file (0))
4264 strncpy (fname
, strrchr (get_exec_file (0), '/') + 1, sizeof (fname
));
4265 strncpy (psargs
, get_exec_file (0), sizeof (psargs
));
4266 if (get_inferior_args ())
4269 char *psargs_end
= psargs
+ sizeof (psargs
);
4271 /* linux_elfcore_write_prpsinfo () handles zero unterminated
4273 string_end
= memchr (psargs
, 0, sizeof (psargs
));
4274 if (string_end
!= NULL
)
4276 *string_end
++ = ' ';
4277 strncpy (string_end
, get_inferior_args (),
4278 psargs_end
- string_end
);
4281 note_data
= (char *) elfcore_write_prpsinfo (obfd
,
4283 note_size
, fname
, psargs
);
4286 /* Dump information for threads. */
4287 thread_args
.obfd
= obfd
;
4288 thread_args
.note_data
= note_data
;
4289 thread_args
.note_size
= note_size
;
4290 thread_args
.num_notes
= 0;
4291 thread_args
.stop_signal
= find_stop_signal ();
4292 iterate_over_lwps (filter
, linux_nat_corefile_thread_callback
, &thread_args
);
4293 gdb_assert (thread_args
.num_notes
!= 0);
4294 note_data
= thread_args
.note_data
;
4296 auxv_len
= target_read_alloc (¤t_target
, TARGET_OBJECT_AUXV
,
4300 note_data
= elfcore_write_note (obfd
, note_data
, note_size
,
4301 "CORE", NT_AUXV
, auxv
, auxv_len
);
4305 note_data
= linux_spu_make_corefile_notes (obfd
, note_data
, note_size
);
4307 make_cleanup (xfree
, note_data
);
4311 /* Implement the "info proc" command. */
4314 linux_nat_info_proc_cmd (char *args
, int from_tty
)
4316 /* A long is used for pid instead of an int to avoid a loss of precision
4317 compiler warning from the output of strtoul. */
4318 long pid
= PIDGET (inferior_ptid
);
4321 char buffer
[MAXPATHLEN
];
4322 char fname1
[MAXPATHLEN
], fname2
[MAXPATHLEN
];
4335 /* Break up 'args' into an argv array. */
4336 argv
= gdb_buildargv (args
);
4337 make_cleanup_freeargv (argv
);
4339 while (argv
!= NULL
&& *argv
!= NULL
)
4341 if (isdigit (argv
[0][0]))
4343 pid
= strtoul (argv
[0], NULL
, 10);
4345 else if (strncmp (argv
[0], "mappings", strlen (argv
[0])) == 0)
4349 else if (strcmp (argv
[0], "status") == 0)
4353 else if (strcmp (argv
[0], "stat") == 0)
4357 else if (strcmp (argv
[0], "cmd") == 0)
4361 else if (strncmp (argv
[0], "exe", strlen (argv
[0])) == 0)
4365 else if (strcmp (argv
[0], "cwd") == 0)
4369 else if (strncmp (argv
[0], "all", strlen (argv
[0])) == 0)
4375 /* [...] (future options here) */
4380 error (_("No current process: you must name one."));
4382 sprintf (fname1
, "/proc/%ld", pid
);
4383 if (stat (fname1
, &dummy
) != 0)
4384 error (_("No /proc directory: '%s'"), fname1
);
4386 printf_filtered (_("process %ld\n"), pid
);
4387 if (cmdline_f
|| all
)
4389 sprintf (fname1
, "/proc/%ld/cmdline", pid
);
4390 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4392 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
4393 if (fgets (buffer
, sizeof (buffer
), procfile
))
4394 printf_filtered ("cmdline = '%s'\n", buffer
);
4396 warning (_("unable to read '%s'"), fname1
);
4397 do_cleanups (cleanup
);
4400 warning (_("unable to open /proc file '%s'"), fname1
);
4404 sprintf (fname1
, "/proc/%ld/cwd", pid
);
4405 memset (fname2
, 0, sizeof (fname2
));
4406 if (readlink (fname1
, fname2
, sizeof (fname2
)) > 0)
4407 printf_filtered ("cwd = '%s'\n", fname2
);
4409 warning (_("unable to read link '%s'"), fname1
);
4413 sprintf (fname1
, "/proc/%ld/exe", pid
);
4414 memset (fname2
, 0, sizeof (fname2
));
4415 if (readlink (fname1
, fname2
, sizeof (fname2
)) > 0)
4416 printf_filtered ("exe = '%s'\n", fname2
);
4418 warning (_("unable to read link '%s'"), fname1
);
4420 if (mappings_f
|| all
)
4422 sprintf (fname1
, "/proc/%ld/maps", pid
);
4423 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4425 long long addr
, endaddr
, size
, offset
, inode
;
4426 char permissions
[8], device
[8], filename
[MAXPATHLEN
];
4427 struct cleanup
*cleanup
;
4429 cleanup
= make_cleanup_fclose (procfile
);
4430 printf_filtered (_("Mapped address spaces:\n\n"));
4431 if (gdbarch_addr_bit (target_gdbarch
) == 32)
4433 printf_filtered ("\t%10s %10s %10s %10s %7s\n",
4436 " Size", " Offset", "objfile");
4440 printf_filtered (" %18s %18s %10s %10s %7s\n",
4443 " Size", " Offset", "objfile");
4446 while (read_mapping (procfile
, &addr
, &endaddr
, &permissions
[0],
4447 &offset
, &device
[0], &inode
, &filename
[0]))
4449 size
= endaddr
- addr
;
4451 /* FIXME: carlton/2003-08-27: Maybe the printf_filtered
4452 calls here (and possibly above) should be abstracted
4453 out into their own functions? Andrew suggests using
4454 a generic local_address_string instead to print out
4455 the addresses; that makes sense to me, too. */
4457 if (gdbarch_addr_bit (target_gdbarch
) == 32)
4459 printf_filtered ("\t%#10lx %#10lx %#10x %#10x %7s\n",
4460 (unsigned long) addr
, /* FIXME: pr_addr */
4461 (unsigned long) endaddr
,
4463 (unsigned int) offset
,
4464 filename
[0] ? filename
: "");
4468 printf_filtered (" %#18lx %#18lx %#10x %#10x %7s\n",
4469 (unsigned long) addr
, /* FIXME: pr_addr */
4470 (unsigned long) endaddr
,
4472 (unsigned int) offset
,
4473 filename
[0] ? filename
: "");
4477 do_cleanups (cleanup
);
4480 warning (_("unable to open /proc file '%s'"), fname1
);
4482 if (status_f
|| all
)
4484 sprintf (fname1
, "/proc/%ld/status", pid
);
4485 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4487 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
4488 while (fgets (buffer
, sizeof (buffer
), procfile
) != NULL
)
4489 puts_filtered (buffer
);
4490 do_cleanups (cleanup
);
4493 warning (_("unable to open /proc file '%s'"), fname1
);
4497 sprintf (fname1
, "/proc/%ld/stat", pid
);
4498 if ((procfile
= fopen (fname1
, "r")) != NULL
)
4503 struct cleanup
*cleanup
= make_cleanup_fclose (procfile
);
4505 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4506 printf_filtered (_("Process: %d\n"), itmp
);
4507 if (fscanf (procfile
, "(%[^)]) ", &buffer
[0]) > 0)
4508 printf_filtered (_("Exec file: %s\n"), buffer
);
4509 if (fscanf (procfile
, "%c ", &ctmp
) > 0)
4510 printf_filtered (_("State: %c\n"), ctmp
);
4511 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4512 printf_filtered (_("Parent process: %d\n"), itmp
);
4513 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4514 printf_filtered (_("Process group: %d\n"), itmp
);
4515 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4516 printf_filtered (_("Session id: %d\n"), itmp
);
4517 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4518 printf_filtered (_("TTY: %d\n"), itmp
);
4519 if (fscanf (procfile
, "%d ", &itmp
) > 0)
4520 printf_filtered (_("TTY owner process group: %d\n"), itmp
);
4521 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4522 printf_filtered (_("Flags: 0x%lx\n"), ltmp
);
4523 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4524 printf_filtered (_("Minor faults (no memory page): %lu\n"),
4525 (unsigned long) ltmp
);
4526 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4527 printf_filtered (_("Minor faults, children: %lu\n"),
4528 (unsigned long) ltmp
);
4529 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4530 printf_filtered (_("Major faults (memory page faults): %lu\n"),
4531 (unsigned long) ltmp
);
4532 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4533 printf_filtered (_("Major faults, children: %lu\n"),
4534 (unsigned long) ltmp
);
4535 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4536 printf_filtered (_("utime: %ld\n"), ltmp
);
4537 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4538 printf_filtered (_("stime: %ld\n"), ltmp
);
4539 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4540 printf_filtered (_("utime, children: %ld\n"), ltmp
);
4541 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4542 printf_filtered (_("stime, children: %ld\n"), ltmp
);
4543 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4544 printf_filtered (_("jiffies remaining in current time slice: %ld\n"),
4546 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4547 printf_filtered (_("'nice' value: %ld\n"), ltmp
);
4548 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4549 printf_filtered (_("jiffies until next timeout: %lu\n"),
4550 (unsigned long) ltmp
);
4551 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4552 printf_filtered (_("jiffies until next SIGALRM: %lu\n"),
4553 (unsigned long) ltmp
);
4554 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4555 printf_filtered (_("start time (jiffies since system boot): %ld\n"),
4557 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4558 printf_filtered (_("Virtual memory size: %lu\n"),
4559 (unsigned long) ltmp
);
4560 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4561 printf_filtered (_("Resident set size: %lu\n"), (unsigned long) ltmp
);
4562 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4563 printf_filtered (_("rlim: %lu\n"), (unsigned long) ltmp
);
4564 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4565 printf_filtered (_("Start of text: 0x%lx\n"), ltmp
);
4566 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4567 printf_filtered (_("End of text: 0x%lx\n"), ltmp
);
4568 if (fscanf (procfile
, "%lu ", <mp
) > 0)
4569 printf_filtered (_("Start of stack: 0x%lx\n"), ltmp
);
4570 #if 0 /* Don't know how architecture-dependent the rest is...
4571 Anyway the signal bitmap info is available from "status". */
4572 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
4573 printf_filtered (_("Kernel stack pointer: 0x%lx\n"), ltmp
);
4574 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
4575 printf_filtered (_("Kernel instr pointer: 0x%lx\n"), ltmp
);
4576 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4577 printf_filtered (_("Pending signals bitmap: 0x%lx\n"), ltmp
);
4578 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4579 printf_filtered (_("Blocked signals bitmap: 0x%lx\n"), ltmp
);
4580 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4581 printf_filtered (_("Ignored signals bitmap: 0x%lx\n"), ltmp
);
4582 if (fscanf (procfile
, "%ld ", <mp
) > 0)
4583 printf_filtered (_("Catched signals bitmap: 0x%lx\n"), ltmp
);
4584 if (fscanf (procfile
, "%lu ", <mp
) > 0) /* FIXME arch? */
4585 printf_filtered (_("wchan (system call): 0x%lx\n"), ltmp
);
4587 do_cleanups (cleanup
);
4590 warning (_("unable to open /proc file '%s'"), fname1
);
4594 /* Implement the to_xfer_partial interface for memory reads using the /proc
4595 filesystem. Because we can use a single read() call for /proc, this
4596 can be much more efficient than banging away at PTRACE_PEEKTEXT,
4597 but it doesn't support writes. */
4600 linux_proc_xfer_partial (struct target_ops
*ops
, enum target_object object
,
4601 const char *annex
, gdb_byte
*readbuf
,
4602 const gdb_byte
*writebuf
,
4603 ULONGEST offset
, LONGEST len
)
4609 if (object
!= TARGET_OBJECT_MEMORY
|| !readbuf
)
4612 /* Don't bother for one word. */
4613 if (len
< 3 * sizeof (long))
4616 /* We could keep this file open and cache it - possibly one per
4617 thread. That requires some juggling, but is even faster. */
4618 sprintf (filename
, "/proc/%d/mem", PIDGET (inferior_ptid
));
4619 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4623 /* If pread64 is available, use it. It's faster if the kernel
4624 supports it (only one syscall), and it's 64-bit safe even on
4625 32-bit platforms (for instance, SPARC debugging a SPARC64
4628 if (pread64 (fd
, readbuf
, len
, offset
) != len
)
4630 if (lseek (fd
, offset
, SEEK_SET
) == -1 || read (fd
, readbuf
, len
) != len
)
4641 /* Enumerate spufs IDs for process PID. */
4643 spu_enumerate_spu_ids (int pid
, gdb_byte
*buf
, ULONGEST offset
, LONGEST len
)
4645 enum bfd_endian byte_order
= gdbarch_byte_order (target_gdbarch
);
4647 LONGEST written
= 0;
4650 struct dirent
*entry
;
4652 xsnprintf (path
, sizeof path
, "/proc/%d/fd", pid
);
4653 dir
= opendir (path
);
4658 while ((entry
= readdir (dir
)) != NULL
)
4664 fd
= atoi (entry
->d_name
);
4668 xsnprintf (path
, sizeof path
, "/proc/%d/fd/%d", pid
, fd
);
4669 if (stat (path
, &st
) != 0)
4671 if (!S_ISDIR (st
.st_mode
))
4674 if (statfs (path
, &stfs
) != 0)
4676 if (stfs
.f_type
!= SPUFS_MAGIC
)
4679 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
4681 store_unsigned_integer (buf
+ pos
- offset
, 4, byte_order
, fd
);
4691 /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU
4692 object type, using the /proc file system. */
4694 linux_proc_xfer_spu (struct target_ops
*ops
, enum target_object object
,
4695 const char *annex
, gdb_byte
*readbuf
,
4696 const gdb_byte
*writebuf
,
4697 ULONGEST offset
, LONGEST len
)
4702 int pid
= PIDGET (inferior_ptid
);
4709 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
4712 xsnprintf (buf
, sizeof buf
, "/proc/%d/fd/%s", pid
, annex
);
4713 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
4718 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4725 ret
= write (fd
, writebuf
, (size_t) len
);
4727 ret
= read (fd
, readbuf
, (size_t) len
);
4734 /* Parse LINE as a signal set and add its set bits to SIGS. */
4737 add_line_to_sigset (const char *line
, sigset_t
*sigs
)
4739 int len
= strlen (line
) - 1;
4743 if (line
[len
] != '\n')
4744 error (_("Could not parse signal set: %s"), line
);
4752 if (*p
>= '0' && *p
<= '9')
4754 else if (*p
>= 'a' && *p
<= 'f')
4755 digit
= *p
- 'a' + 10;
4757 error (_("Could not parse signal set: %s"), line
);
4762 sigaddset (sigs
, signum
+ 1);
4764 sigaddset (sigs
, signum
+ 2);
4766 sigaddset (sigs
, signum
+ 3);
4768 sigaddset (sigs
, signum
+ 4);
4774 /* Find process PID's pending signals from /proc/pid/status and set
4778 linux_proc_pending_signals (int pid
, sigset_t
*pending
, sigset_t
*blocked
, sigset_t
*ignored
)
4781 char buffer
[MAXPATHLEN
], fname
[MAXPATHLEN
];
4783 struct cleanup
*cleanup
;
4785 sigemptyset (pending
);
4786 sigemptyset (blocked
);
4787 sigemptyset (ignored
);
4788 sprintf (fname
, "/proc/%d/status", pid
);
4789 procfile
= fopen (fname
, "r");
4790 if (procfile
== NULL
)
4791 error (_("Could not open %s"), fname
);
4792 cleanup
= make_cleanup_fclose (procfile
);
4794 while (fgets (buffer
, MAXPATHLEN
, procfile
) != NULL
)
4796 /* Normal queued signals are on the SigPnd line in the status
4797 file. However, 2.6 kernels also have a "shared" pending
4798 queue for delivering signals to a thread group, so check for
4801 Unfortunately some Red Hat kernels include the shared pending
4802 queue but not the ShdPnd status field. */
4804 if (strncmp (buffer
, "SigPnd:\t", 8) == 0)
4805 add_line_to_sigset (buffer
+ 8, pending
);
4806 else if (strncmp (buffer
, "ShdPnd:\t", 8) == 0)
4807 add_line_to_sigset (buffer
+ 8, pending
);
4808 else if (strncmp (buffer
, "SigBlk:\t", 8) == 0)
4809 add_line_to_sigset (buffer
+ 8, blocked
);
4810 else if (strncmp (buffer
, "SigIgn:\t", 8) == 0)
4811 add_line_to_sigset (buffer
+ 8, ignored
);
4814 do_cleanups (cleanup
);
4818 linux_nat_xfer_osdata (struct target_ops
*ops
, enum target_object object
,
4819 const char *annex
, gdb_byte
*readbuf
,
4820 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
4822 /* We make the process list snapshot when the object starts to be
4824 static const char *buf
;
4825 static LONGEST len_avail
= -1;
4826 static struct obstack obstack
;
4830 gdb_assert (object
== TARGET_OBJECT_OSDATA
);
4832 if (strcmp (annex
, "processes") != 0)
4835 gdb_assert (readbuf
&& !writebuf
);
4839 if (len_avail
!= -1 && len_avail
!= 0)
4840 obstack_free (&obstack
, NULL
);
4843 obstack_init (&obstack
);
4844 obstack_grow_str (&obstack
, "<osdata type=\"processes\">\n");
4846 dirp
= opendir ("/proc");
4850 while ((dp
= readdir (dirp
)) != NULL
)
4852 struct stat statbuf
;
4853 char procentry
[sizeof ("/proc/4294967295")];
4855 if (!isdigit (dp
->d_name
[0])
4856 || NAMELEN (dp
) > sizeof ("4294967295") - 1)
4859 sprintf (procentry
, "/proc/%s", dp
->d_name
);
4860 if (stat (procentry
, &statbuf
) == 0
4861 && S_ISDIR (statbuf
.st_mode
))
4865 char cmd
[MAXPATHLEN
+ 1];
4866 struct passwd
*entry
;
4868 pathname
= xstrprintf ("/proc/%s/cmdline", dp
->d_name
);
4869 entry
= getpwuid (statbuf
.st_uid
);
4871 if ((f
= fopen (pathname
, "r")) != NULL
)
4873 size_t len
= fread (cmd
, 1, sizeof (cmd
) - 1, f
);
4877 for (i
= 0; i
< len
; i
++)
4882 obstack_xml_printf (
4885 "<column name=\"pid\">%s</column>"
4886 "<column name=\"user\">%s</column>"
4887 "<column name=\"command\">%s</column>"
4890 entry
? entry
->pw_name
: "?",
4903 obstack_grow_str0 (&obstack
, "</osdata>\n");
4904 buf
= obstack_finish (&obstack
);
4905 len_avail
= strlen (buf
);
4908 if (offset
>= len_avail
)
4910 /* Done. Get rid of the obstack. */
4911 obstack_free (&obstack
, NULL
);
4917 if (len
> len_avail
- offset
)
4918 len
= len_avail
- offset
;
4919 memcpy (readbuf
, buf
+ offset
, len
);
4925 linux_xfer_partial (struct target_ops
*ops
, enum target_object object
,
4926 const char *annex
, gdb_byte
*readbuf
,
4927 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
4931 if (object
== TARGET_OBJECT_AUXV
)
4932 return procfs_xfer_auxv (ops
, object
, annex
, readbuf
, writebuf
,
4935 if (object
== TARGET_OBJECT_OSDATA
)
4936 return linux_nat_xfer_osdata (ops
, object
, annex
, readbuf
, writebuf
,
4939 if (object
== TARGET_OBJECT_SPU
)
4940 return linux_proc_xfer_spu (ops
, object
, annex
, readbuf
, writebuf
,
4943 /* GDB calculates all the addresses in possibly larget width of the address.
4944 Address width needs to be masked before its final use - either by
4945 linux_proc_xfer_partial or inf_ptrace_xfer_partial.
4947 Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */
4949 if (object
== TARGET_OBJECT_MEMORY
)
4951 int addr_bit
= gdbarch_addr_bit (target_gdbarch
);
4953 if (addr_bit
< (sizeof (ULONGEST
) * HOST_CHAR_BIT
))
4954 offset
&= ((ULONGEST
) 1 << addr_bit
) - 1;
4957 xfer
= linux_proc_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
4962 return super_xfer_partial (ops
, object
, annex
, readbuf
, writebuf
,
4966 /* Create a prototype generic GNU/Linux target. The client can override
4967 it with local methods. */
4970 linux_target_install_ops (struct target_ops
*t
)
4972 t
->to_insert_fork_catchpoint
= linux_child_insert_fork_catchpoint
;
4973 t
->to_insert_vfork_catchpoint
= linux_child_insert_vfork_catchpoint
;
4974 t
->to_insert_exec_catchpoint
= linux_child_insert_exec_catchpoint
;
4975 t
->to_set_syscall_catchpoint
= linux_child_set_syscall_catchpoint
;
4976 t
->to_pid_to_exec_file
= linux_child_pid_to_exec_file
;
4977 t
->to_post_startup_inferior
= linux_child_post_startup_inferior
;
4978 t
->to_post_attach
= linux_child_post_attach
;
4979 t
->to_follow_fork
= linux_child_follow_fork
;
4980 t
->to_find_memory_regions
= linux_nat_find_memory_regions
;
4981 t
->to_make_corefile_notes
= linux_nat_make_corefile_notes
;
4983 super_xfer_partial
= t
->to_xfer_partial
;
4984 t
->to_xfer_partial
= linux_xfer_partial
;
4990 struct target_ops
*t
;
4992 t
= inf_ptrace_target ();
4993 linux_target_install_ops (t
);
4999 linux_trad_target (CORE_ADDR (*register_u_offset
)(struct gdbarch
*, int, int))
5001 struct target_ops
*t
;
5003 t
= inf_ptrace_trad_target (register_u_offset
);
5004 linux_target_install_ops (t
);
5009 /* target_is_async_p implementation. */
5012 linux_nat_is_async_p (void)
5014 /* NOTE: palves 2008-03-21: We're only async when the user requests
5015 it explicitly with the "set target-async" command.
5016 Someday, linux will always be async. */
5017 if (!target_async_permitted
)
5020 /* See target.h/target_async_mask. */
5021 return linux_nat_async_mask_value
;
5024 /* target_can_async_p implementation. */
5027 linux_nat_can_async_p (void)
5029 /* NOTE: palves 2008-03-21: We're only async when the user requests
5030 it explicitly with the "set target-async" command.
5031 Someday, linux will always be async. */
5032 if (!target_async_permitted
)
5035 /* See target.h/target_async_mask. */
5036 return linux_nat_async_mask_value
;
5040 linux_nat_supports_non_stop (void)
5045 /* True if we want to support multi-process. To be removed when GDB
5046 supports multi-exec. */
5048 int linux_multi_process
= 1;
5051 linux_nat_supports_multi_process (void)
5053 return linux_multi_process
;
5056 /* target_async_mask implementation. */
5059 linux_nat_async_mask (int new_mask
)
5061 int curr_mask
= linux_nat_async_mask_value
;
5063 if (curr_mask
!= new_mask
)
5067 linux_nat_async (NULL
, 0);
5068 linux_nat_async_mask_value
= new_mask
;
5072 linux_nat_async_mask_value
= new_mask
;
5074 /* If we're going out of async-mask in all-stop, then the
5075 inferior is stopped. The next resume will call
5076 target_async. In non-stop, the target event source
5077 should be always registered in the event loop. Do so
5080 linux_nat_async (inferior_event_handler
, 0);
5087 static int async_terminal_is_ours
= 1;
5089 /* target_terminal_inferior implementation. */
5092 linux_nat_terminal_inferior (void)
5094 if (!target_is_async_p ())
5096 /* Async mode is disabled. */
5097 terminal_inferior ();
5101 terminal_inferior ();
5103 /* Calls to target_terminal_*() are meant to be idempotent. */
5104 if (!async_terminal_is_ours
)
5107 delete_file_handler (input_fd
);
5108 async_terminal_is_ours
= 0;
5112 /* target_terminal_ours implementation. */
5115 linux_nat_terminal_ours (void)
5117 if (!target_is_async_p ())
5119 /* Async mode is disabled. */
5124 /* GDB should never give the terminal to the inferior if the
5125 inferior is running in the background (run&, continue&, etc.),
5126 but claiming it sure should. */
5129 if (async_terminal_is_ours
)
5132 clear_sigint_trap ();
5133 add_file_handler (input_fd
, stdin_event_handler
, 0);
5134 async_terminal_is_ours
= 1;
5137 static void (*async_client_callback
) (enum inferior_event_type event_type
,
5139 static void *async_client_context
;
5141 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5142 so we notice when any child changes state, and notify the
5143 event-loop; it allows us to use sigsuspend in linux_nat_wait_1
5144 above to wait for the arrival of a SIGCHLD. */
5147 sigchld_handler (int signo
)
5149 int old_errno
= errno
;
5151 if (debug_linux_nat_async
)
5152 fprintf_unfiltered (gdb_stdlog
, "sigchld\n");
5154 if (signo
== SIGCHLD
5155 && linux_nat_event_pipe
[0] != -1)
5156 async_file_mark (); /* Let the event loop know that there are
5157 events to handle. */
5162 /* Callback registered with the target events file descriptor. */
5165 handle_target_event (int error
, gdb_client_data client_data
)
5167 (*async_client_callback
) (INF_REG_EVENT
, async_client_context
);
5170 /* Create/destroy the target events pipe. Returns previous state. */
5173 linux_async_pipe (int enable
)
5175 int previous
= (linux_nat_event_pipe
[0] != -1);
5177 if (previous
!= enable
)
5181 block_child_signals (&prev_mask
);
5185 if (pipe (linux_nat_event_pipe
) == -1)
5186 internal_error (__FILE__
, __LINE__
,
5187 "creating event pipe failed.");
5189 fcntl (linux_nat_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5190 fcntl (linux_nat_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5194 close (linux_nat_event_pipe
[0]);
5195 close (linux_nat_event_pipe
[1]);
5196 linux_nat_event_pipe
[0] = -1;
5197 linux_nat_event_pipe
[1] = -1;
5200 restore_child_signals_mask (&prev_mask
);
5206 /* target_async implementation. */
5209 linux_nat_async (void (*callback
) (enum inferior_event_type event_type
,
5210 void *context
), void *context
)
5212 if (linux_nat_async_mask_value
== 0 || !target_async_permitted
)
5213 internal_error (__FILE__
, __LINE__
,
5214 "Calling target_async when async is masked");
5216 if (callback
!= NULL
)
5218 async_client_callback
= callback
;
5219 async_client_context
= context
;
5220 if (!linux_async_pipe (1))
5222 add_file_handler (linux_nat_event_pipe
[0],
5223 handle_target_event
, NULL
);
5224 /* There may be pending events to handle. Tell the event loop
5231 async_client_callback
= callback
;
5232 async_client_context
= context
;
5233 delete_file_handler (linux_nat_event_pipe
[0]);
5234 linux_async_pipe (0);
5239 /* Stop an LWP, and push a TARGET_SIGNAL_0 stop status if no other
5243 linux_nat_stop_lwp (struct lwp_info
*lwp
, void *data
)
5248 ptid_t ptid
= lwp
->ptid
;
5250 if (debug_linux_nat
)
5251 fprintf_unfiltered (gdb_stdlog
,
5252 "LNSL: running -> suspending %s\n",
5253 target_pid_to_str (lwp
->ptid
));
5256 stop_callback (lwp
, NULL
);
5257 stop_wait_callback (lwp
, NULL
);
5259 /* If the lwp exits while we try to stop it, there's nothing
5261 lwp
= find_lwp_pid (ptid
);
5265 /* If we didn't collect any signal other than SIGSTOP while
5266 stopping the LWP, push a SIGNAL_0 event. In either case, the
5267 event-loop will end up calling target_wait which will collect
5269 if (lwp
->status
== 0)
5270 lwp
->status
= W_STOPCODE (0);
5275 /* Already known to be stopped; do nothing. */
5277 if (debug_linux_nat
)
5279 if (find_thread_ptid (lwp
->ptid
)->stop_requested
)
5280 fprintf_unfiltered (gdb_stdlog
, "\
5281 LNSL: already stopped/stop_requested %s\n",
5282 target_pid_to_str (lwp
->ptid
));
5284 fprintf_unfiltered (gdb_stdlog
, "\
5285 LNSL: already stopped/no stop_requested yet %s\n",
5286 target_pid_to_str (lwp
->ptid
));
5293 linux_nat_stop (ptid_t ptid
)
5296 iterate_over_lwps (ptid
, linux_nat_stop_lwp
, NULL
);
5298 linux_ops
->to_stop (ptid
);
5302 linux_nat_close (int quitting
)
5304 /* Unregister from the event loop. */
5305 if (target_is_async_p ())
5306 target_async (NULL
, 0);
5308 /* Reset the async_masking. */
5309 linux_nat_async_mask_value
= 1;
5311 if (linux_ops
->to_close
)
5312 linux_ops
->to_close (quitting
);
5315 /* When requests are passed down from the linux-nat layer to the
5316 single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are
5317 used. The address space pointer is stored in the inferior object,
5318 but the common code that is passed such ptid can't tell whether
5319 lwpid is a "main" process id or not (it assumes so). We reverse
5320 look up the "main" process id from the lwp here. */
5322 struct address_space
*
5323 linux_nat_thread_address_space (struct target_ops
*t
, ptid_t ptid
)
5325 struct lwp_info
*lwp
;
5326 struct inferior
*inf
;
5329 pid
= GET_LWP (ptid
);
5330 if (GET_LWP (ptid
) == 0)
5332 /* An (lwpid,0,0) ptid. Look up the lwp object to get at the
5334 lwp
= find_lwp_pid (ptid
);
5335 pid
= GET_PID (lwp
->ptid
);
5339 /* A (pid,lwpid,0) ptid. */
5340 pid
= GET_PID (ptid
);
5343 inf
= find_inferior_pid (pid
);
5344 gdb_assert (inf
!= NULL
);
5349 linux_nat_add_target (struct target_ops
*t
)
5351 /* Save the provided single-threaded target. We save this in a separate
5352 variable because another target we've inherited from (e.g. inf-ptrace)
5353 may have saved a pointer to T; we want to use it for the final
5354 process stratum target. */
5355 linux_ops_saved
= *t
;
5356 linux_ops
= &linux_ops_saved
;
5358 /* Override some methods for multithreading. */
5359 t
->to_create_inferior
= linux_nat_create_inferior
;
5360 t
->to_attach
= linux_nat_attach
;
5361 t
->to_detach
= linux_nat_detach
;
5362 t
->to_resume
= linux_nat_resume
;
5363 t
->to_wait
= linux_nat_wait
;
5364 t
->to_xfer_partial
= linux_nat_xfer_partial
;
5365 t
->to_kill
= linux_nat_kill
;
5366 t
->to_mourn_inferior
= linux_nat_mourn_inferior
;
5367 t
->to_thread_alive
= linux_nat_thread_alive
;
5368 t
->to_pid_to_str
= linux_nat_pid_to_str
;
5369 t
->to_has_thread_control
= tc_schedlock
;
5370 t
->to_thread_address_space
= linux_nat_thread_address_space
;
5372 t
->to_can_async_p
= linux_nat_can_async_p
;
5373 t
->to_is_async_p
= linux_nat_is_async_p
;
5374 t
->to_supports_non_stop
= linux_nat_supports_non_stop
;
5375 t
->to_async
= linux_nat_async
;
5376 t
->to_async_mask
= linux_nat_async_mask
;
5377 t
->to_terminal_inferior
= linux_nat_terminal_inferior
;
5378 t
->to_terminal_ours
= linux_nat_terminal_ours
;
5379 t
->to_close
= linux_nat_close
;
5381 /* Methods for non-stop support. */
5382 t
->to_stop
= linux_nat_stop
;
5384 t
->to_supports_multi_process
= linux_nat_supports_multi_process
;
5386 /* We don't change the stratum; this target will sit at
5387 process_stratum and thread_db will set at thread_stratum. This
5388 is a little strange, since this is a multi-threaded-capable
5389 target, but we want to be on the stack below thread_db, and we
5390 also want to be used for single-threaded processes. */
5395 /* Register a method to call whenever a new thread is attached. */
5397 linux_nat_set_new_thread (struct target_ops
*t
, void (*new_thread
) (ptid_t
))
5399 /* Save the pointer. We only support a single registered instance
5400 of the GNU/Linux native target, so we do not need to map this to
5402 linux_nat_new_thread
= new_thread
;
5405 /* Register a method that converts a siginfo object between the layout
5406 that ptrace returns, and the layout in the architecture of the
5409 linux_nat_set_siginfo_fixup (struct target_ops
*t
,
5410 int (*siginfo_fixup
) (struct siginfo
*,
5414 /* Save the pointer. */
5415 linux_nat_siginfo_fixup
= siginfo_fixup
;
5418 /* Return the saved siginfo associated with PTID. */
5420 linux_nat_get_siginfo (ptid_t ptid
)
5422 struct lwp_info
*lp
= find_lwp_pid (ptid
);
5424 gdb_assert (lp
!= NULL
);
5426 return &lp
->siginfo
;
5429 /* Provide a prototype to silence -Wmissing-prototypes. */
5430 extern initialize_file_ftype _initialize_linux_nat
;
5433 _initialize_linux_nat (void)
5437 add_info ("proc", linux_nat_info_proc_cmd
, _("\
5438 Show /proc process information about any running process.\n\
5439 Specify any process id, or use the program being debugged by default.\n\
5440 Specify any of the following keywords for detailed info:\n\
5441 mappings -- list of mapped memory regions.\n\
5442 stat -- list a bunch of random process info.\n\
5443 status -- list a different bunch of random process info.\n\
5444 all -- list all available /proc info."));
5446 add_setshow_zinteger_cmd ("lin-lwp", class_maintenance
,
5447 &debug_linux_nat
, _("\
5448 Set debugging of GNU/Linux lwp module."), _("\
5449 Show debugging of GNU/Linux lwp module."), _("\
5450 Enables printf debugging output."),
5452 show_debug_linux_nat
,
5453 &setdebuglist
, &showdebuglist
);
5455 add_setshow_zinteger_cmd ("lin-lwp-async", class_maintenance
,
5456 &debug_linux_nat_async
, _("\
5457 Set debugging of GNU/Linux async lwp module."), _("\
5458 Show debugging of GNU/Linux async lwp module."), _("\
5459 Enables printf debugging output."),
5461 show_debug_linux_nat_async
,
5462 &setdebuglist
, &showdebuglist
);
5464 /* Save this mask as the default. */
5465 sigprocmask (SIG_SETMASK
, NULL
, &normal_mask
);
5467 /* Install a SIGCHLD handler. */
5468 sigchld_action
.sa_handler
= sigchld_handler
;
5469 sigemptyset (&sigchld_action
.sa_mask
);
5470 sigchld_action
.sa_flags
= SA_RESTART
;
5472 /* Make it the default. */
5473 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
5475 /* Make sure we don't block SIGCHLD during a sigsuspend. */
5476 sigprocmask (SIG_SETMASK
, NULL
, &suspend_mask
);
5477 sigdelset (&suspend_mask
, SIGCHLD
);
5479 sigemptyset (&blocked_mask
);
5481 add_setshow_boolean_cmd ("disable-randomization", class_support
,
5482 &disable_randomization
, _("\
5483 Set disabling of debuggee's virtual address space randomization."), _("\
5484 Show disabling of debuggee's virtual address space randomization."), _("\
5485 When this mode is on (which is the default), randomization of the virtual\n\
5486 address space is disabled. Standalone programs run with the randomization\n\
5487 enabled by default on some platforms."),
5488 &set_disable_randomization
,
5489 &show_disable_randomization
,
5490 &setlist
, &showlist
);
5494 /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to
5495 the GNU/Linux Threads library and therefore doesn't really belong
5498 /* Read variable NAME in the target and return its value if found.
5499 Otherwise return zero. It is assumed that the type of the variable
5503 get_signo (const char *name
)
5505 struct minimal_symbol
*ms
;
5508 ms
= lookup_minimal_symbol (name
, NULL
, NULL
);
5512 if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms
), (gdb_byte
*) &signo
,
5513 sizeof (signo
)) != 0)
5519 /* Return the set of signals used by the threads library in *SET. */
5522 lin_thread_get_thread_signals (sigset_t
*set
)
5524 struct sigaction action
;
5525 int restart
, cancel
;
5527 sigemptyset (&blocked_mask
);
5530 restart
= get_signo ("__pthread_sig_restart");
5531 cancel
= get_signo ("__pthread_sig_cancel");
5533 /* LinuxThreads normally uses the first two RT signals, but in some legacy
5534 cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does
5535 not provide any way for the debugger to query the signal numbers -
5536 fortunately they don't change! */
5539 restart
= __SIGRTMIN
;
5542 cancel
= __SIGRTMIN
+ 1;
5544 sigaddset (set
, restart
);
5545 sigaddset (set
, cancel
);
5547 /* The GNU/Linux Threads library makes terminating threads send a
5548 special "cancel" signal instead of SIGCHLD. Make sure we catch
5549 those (to prevent them from terminating GDB itself, which is
5550 likely to be their default action) and treat them the same way as
5553 action
.sa_handler
= sigchld_handler
;
5554 sigemptyset (&action
.sa_mask
);
5555 action
.sa_flags
= SA_RESTART
;
5556 sigaction (cancel
, &action
, NULL
);
5558 /* We block the "cancel" signal throughout this code ... */
5559 sigaddset (&blocked_mask
, cancel
);
5560 sigprocmask (SIG_BLOCK
, &blocked_mask
, NULL
);
5562 /* ... except during a sigsuspend. */
5563 sigdelset (&suspend_mask
, cancel
);