1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995, 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
3 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 #include "linux-low.h"
22 #include "ansidecl.h" /* For ATTRIBUTE_PACKED, must be bug in external.h. */
23 #include "elf/common.h"
24 #include "elf/external.h"
28 #include <sys/param.h>
29 #include <sys/ptrace.h>
31 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
47 #define SPUFS_MAGIC 0x23c9b64e
50 #ifndef PTRACE_GETSIGINFO
51 # define PTRACE_GETSIGINFO 0x4202
52 # define PTRACE_SETSIGINFO 0x4203
59 /* If the system headers did not provide the constants, hard-code the normal
61 #ifndef PTRACE_EVENT_FORK
63 #define PTRACE_SETOPTIONS 0x4200
64 #define PTRACE_GETEVENTMSG 0x4201
66 /* options set using PTRACE_SETOPTIONS */
67 #define PTRACE_O_TRACESYSGOOD 0x00000001
68 #define PTRACE_O_TRACEFORK 0x00000002
69 #define PTRACE_O_TRACEVFORK 0x00000004
70 #define PTRACE_O_TRACECLONE 0x00000008
71 #define PTRACE_O_TRACEEXEC 0x00000010
72 #define PTRACE_O_TRACEVFORKDONE 0x00000020
73 #define PTRACE_O_TRACEEXIT 0x00000040
75 /* Wait extended result codes for the above trace options. */
76 #define PTRACE_EVENT_FORK 1
77 #define PTRACE_EVENT_VFORK 2
78 #define PTRACE_EVENT_CLONE 3
79 #define PTRACE_EVENT_EXEC 4
80 #define PTRACE_EVENT_VFORK_DONE 5
81 #define PTRACE_EVENT_EXIT 6
83 #endif /* PTRACE_EVENT_FORK */
85 /* We can't always assume that this flag is available, but all systems
86 with the ptrace event handlers also have __WALL, so it's safe to use
89 #define __WALL 0x40000000 /* Wait for any child. */
93 #if !(defined(__UCLIBC_HAS_MMU__) || defined(__ARCH_HAS_MMU__))
98 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
99 representation of the thread ID.
101 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
102 the same as the LWP ID.
104 ``all_processes'' is keyed by the "overall process ID", which
105 GNU/Linux calls tgid, "thread group ID". */
107 struct inferior_list all_lwps
;
109 /* A list of all unknown processes which receive stop signals. Some other
110 process will presumably claim each of these as forked children
113 struct inferior_list stopped_pids
;
115 /* FIXME this is a bit of a hack, and could be removed. */
116 int stopping_threads
;
118 /* FIXME make into a target method? */
119 int using_threads
= 1;
121 /* This flag is true iff we've just created or attached to our first
122 inferior but it has not stopped yet. As soon as it does, we need
123 to call the low target's arch_setup callback. Doing this only on
124 the first inferior avoids reinializing the architecture on every
125 inferior, and avoids messing with the register caches of the
126 already running inferiors. NOTE: this assumes all inferiors under
127 control of gdbserver have the same architecture. */
128 static int new_inferior
;
130 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
131 int step
, int signal
, siginfo_t
*info
);
132 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
133 static void stop_all_lwps (void);
134 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
135 static int check_removed_breakpoint (struct lwp_info
*event_child
);
136 static void *add_lwp (ptid_t ptid
);
137 static int linux_stopped_by_watchpoint (void);
138 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
140 struct pending_signals
144 struct pending_signals
*prev
;
147 #define PTRACE_ARG3_TYPE long
148 #define PTRACE_XFER_TYPE long
150 #ifdef HAVE_LINUX_REGSETS
151 static char *disabled_regsets
;
152 static int num_regsets
;
155 /* The read/write ends of the pipe registered as waitable file in the
157 static int linux_event_pipe
[2] = { -1, -1 };
159 /* True if we're currently in async mode. */
160 #define target_is_async_p() (linux_event_pipe[0] != -1)
162 static void send_sigstop (struct inferior_list_entry
*entry
);
163 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
165 /* Accepts an integer PID; Returns a string representing a file that
166 can be opened to get info for the child process.
167 Space for the result is malloc'd, caller must free. */
170 linux_child_pid_to_exec_file (int pid
)
174 name1
= xmalloc (MAXPATHLEN
);
175 name2
= xmalloc (MAXPATHLEN
);
176 memset (name2
, 0, MAXPATHLEN
);
178 sprintf (name1
, "/proc/%d/exe", pid
);
179 if (readlink (name1
, name2
, MAXPATHLEN
) > 0)
191 /* Return non-zero if HEADER is a 64-bit ELF file. */
194 elf_64_header_p (const Elf64_External_Ehdr
*header
)
196 return (header
->e_ident
[EI_MAG0
] == ELFMAG0
197 && header
->e_ident
[EI_MAG1
] == ELFMAG1
198 && header
->e_ident
[EI_MAG2
] == ELFMAG2
199 && header
->e_ident
[EI_MAG3
] == ELFMAG3
200 && header
->e_ident
[EI_CLASS
] == ELFCLASS64
);
203 /* Return non-zero if FILE is a 64-bit ELF file,
204 zero if the file is not a 64-bit ELF file,
205 and -1 if the file is not accessible or doesn't exist. */
208 elf_64_file_p (const char *file
)
210 Elf64_External_Ehdr header
;
213 fd
= open (file
, O_RDONLY
);
217 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
224 return elf_64_header_p (&header
);
228 delete_lwp (struct lwp_info
*lwp
)
230 remove_thread (get_lwp_thread (lwp
));
231 remove_inferior (&all_lwps
, &lwp
->head
);
232 free (lwp
->arch_private
);
236 /* Add a process to the common process list, and set its private
239 static struct process_info
*
240 linux_add_process (int pid
, int attached
)
242 struct process_info
*proc
;
244 /* Is this the first process? If so, then set the arch. */
245 if (all_processes
.head
== NULL
)
248 proc
= add_process (pid
, attached
);
249 proc
->private = xcalloc (1, sizeof (*proc
->private));
251 if (the_low_target
.new_process
!= NULL
)
252 proc
->private->arch_private
= the_low_target
.new_process ();
257 /* Remove a process from the common process list,
258 also freeing all private data. */
261 linux_remove_process (struct process_info
*process
, int detaching
)
263 struct process_info_private
*priv
= process
->private;
266 thread_db_free (process
, detaching
);
269 free (priv
->arch_private
);
271 remove_process (process
);
274 /* Wrapper function for waitpid which handles EINTR, and emulates
275 __WALL for systems where that is not available. */
278 my_waitpid (int pid
, int *status
, int flags
)
283 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
287 sigset_t block_mask
, org_mask
, wake_mask
;
290 wnohang
= (flags
& WNOHANG
) != 0;
291 flags
&= ~(__WALL
| __WCLONE
);
294 /* Block all signals while here. This avoids knowing about
295 LinuxThread's signals. */
296 sigfillset (&block_mask
);
297 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
299 /* ... except during the sigsuspend below. */
300 sigemptyset (&wake_mask
);
304 /* Since all signals are blocked, there's no need to check
306 ret
= waitpid (pid
, status
, flags
);
309 if (ret
== -1 && out_errno
!= ECHILD
)
314 if (flags
& __WCLONE
)
316 /* We've tried both flavors now. If WNOHANG is set,
317 there's nothing else to do, just bail out. */
322 fprintf (stderr
, "blocking\n");
324 /* Block waiting for signals. */
325 sigsuspend (&wake_mask
);
331 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
336 ret
= waitpid (pid
, status
, flags
);
337 while (ret
== -1 && errno
== EINTR
);
342 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
343 pid
, flags
, status
? *status
: -1, ret
);
349 /* Handle a GNU/Linux extended wait response. If we see a clone
350 event, we need to add the new LWP to our list (and not report the
351 trap to higher layers). */
354 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
356 int event
= wstat
>> 16;
357 struct lwp_info
*new_lwp
;
359 if (event
== PTRACE_EVENT_CLONE
)
362 unsigned long new_pid
;
363 int ret
, status
= W_STOPCODE (SIGSTOP
);
365 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), 0, &new_pid
);
367 /* If we haven't already seen the new PID stop, wait for it now. */
368 if (! pull_pid_from_list (&stopped_pids
, new_pid
))
370 /* The new child has a pending SIGSTOP. We can't affect it until it
371 hits the SIGSTOP, but we're already attached. */
373 ret
= my_waitpid (new_pid
, &status
, __WALL
);
376 perror_with_name ("waiting for new child");
377 else if (ret
!= new_pid
)
378 warning ("wait returned unexpected PID %d", ret
);
379 else if (!WIFSTOPPED (status
))
380 warning ("wait returned unexpected status 0x%x", status
);
383 ptrace (PTRACE_SETOPTIONS
, new_pid
, 0, PTRACE_O_TRACECLONE
);
385 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
386 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
387 add_thread (ptid
, new_lwp
);
389 /* Either we're going to immediately resume the new thread
390 or leave it stopped. linux_resume_one_lwp is a nop if it
391 thinks the thread is currently running, so set this first
392 before calling linux_resume_one_lwp. */
393 new_lwp
->stopped
= 1;
395 /* Normally we will get the pending SIGSTOP. But in some cases
396 we might get another signal delivered to the group first.
397 If we do get another signal, be sure not to lose it. */
398 if (WSTOPSIG (status
) == SIGSTOP
)
400 if (! stopping_threads
)
401 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
405 new_lwp
->stop_expected
= 1;
406 if (stopping_threads
)
408 new_lwp
->status_pending_p
= 1;
409 new_lwp
->status_pending
= status
;
412 /* Pass the signal on. This is what GDB does - except
413 shouldn't we really report it instead? */
414 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
417 /* Always resume the current thread. If we are stopping
418 threads, it will have a pending SIGSTOP; we may as well
420 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
424 /* This function should only be called if the process got a SIGTRAP.
425 The SIGTRAP could mean several things.
427 On i386, where decr_pc_after_break is non-zero:
428 If we were single-stepping this process using PTRACE_SINGLESTEP,
429 we will get only the one SIGTRAP (even if the instruction we
430 stepped over was a breakpoint). The value of $eip will be the
432 If we continue the process using PTRACE_CONT, we will get a
433 SIGTRAP when we hit a breakpoint. The value of $eip will be
434 the instruction after the breakpoint (i.e. needs to be
435 decremented). If we report the SIGTRAP to GDB, we must also
436 report the undecremented PC. If we cancel the SIGTRAP, we
437 must resume at the decremented PC.
439 (Presumably, not yet tested) On a non-decr_pc_after_break machine
440 with hardware or kernel single-step:
441 If we single-step over a breakpoint instruction, our PC will
442 point at the following instruction. If we continue and hit a
443 breakpoint instruction, our PC will point at the breakpoint
449 CORE_ADDR stop_pc
= (*the_low_target
.get_pc
) ();
451 if (! get_thread_lwp (current_inferior
)->stepping
)
452 stop_pc
-= the_low_target
.decr_pc_after_break
;
455 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
461 add_lwp (ptid_t ptid
)
463 struct lwp_info
*lwp
;
465 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
466 memset (lwp
, 0, sizeof (*lwp
));
470 if (the_low_target
.new_thread
!= NULL
)
471 lwp
->arch_private
= the_low_target
.new_thread ();
473 add_inferior_to_list (&all_lwps
, &lwp
->head
);
478 /* Start an inferior process and returns its pid.
479 ALLARGS is a vector of program-name and args. */
482 linux_create_inferior (char *program
, char **allargs
)
484 struct lwp_info
*new_lwp
;
488 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
494 perror_with_name ("fork");
498 ptrace (PTRACE_TRACEME
, 0, 0, 0);
500 signal (__SIGRTMIN
+ 1, SIG_DFL
);
504 execv (program
, allargs
);
506 execvp (program
, allargs
);
508 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
514 linux_add_process (pid
, 0);
516 ptid
= ptid_build (pid
, pid
, 0);
517 new_lwp
= add_lwp (ptid
);
518 add_thread (ptid
, new_lwp
);
519 new_lwp
->must_set_ptrace_flags
= 1;
524 /* Attach to an inferior process. */
527 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
530 struct lwp_info
*new_lwp
;
532 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) != 0)
536 /* If we fail to attach to an LWP, just warn. */
537 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
538 strerror (errno
), errno
);
543 /* If we fail to attach to a process, report an error. */
544 error ("Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
545 strerror (errno
), errno
);
549 /* NOTE/FIXME: This lwp might have not been the tgid. */
550 ptid
= ptid_build (lwpid
, lwpid
, 0);
553 /* Note that extracting the pid from the current inferior is
554 safe, since we're always called in the context of the same
555 process as this new thread. */
556 int pid
= pid_of (get_thread_lwp (current_inferior
));
557 ptid
= ptid_build (pid
, lwpid
, 0);
560 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
561 add_thread (ptid
, new_lwp
);
563 /* We need to wait for SIGSTOP before being able to make the next
564 ptrace call on this LWP. */
565 new_lwp
->must_set_ptrace_flags
= 1;
567 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
570 There are several cases to consider here:
572 1) gdbserver has already attached to the process and is being notified
573 of a new thread that is being created.
574 In this case we should ignore that SIGSTOP and resume the process.
575 This is handled below by setting stop_expected = 1.
577 2) This is the first thread (the process thread), and we're attaching
578 to it via attach_inferior.
579 In this case we want the process thread to stop.
580 This is handled by having linux_attach clear stop_expected after
582 ??? If the process already has several threads we leave the other
585 3) GDB is connecting to gdbserver and is requesting an enumeration of all
587 In this case we want the thread to stop.
588 FIXME: This case is currently not properly handled.
589 We should wait for the SIGSTOP but don't. Things work apparently
590 because enough time passes between when we ptrace (ATTACH) and when
591 gdb makes the next ptrace call on the thread.
593 On the other hand, if we are currently trying to stop all threads, we
594 should treat the new thread as if we had sent it a SIGSTOP. This works
595 because we are guaranteed that the add_lwp call above added us to the
596 end of the list, and so the new thread has not yet reached
597 wait_for_sigstop (but will). */
598 if (! stopping_threads
)
599 new_lwp
->stop_expected
= 1;
603 linux_attach_lwp (unsigned long lwpid
)
605 linux_attach_lwp_1 (lwpid
, 0);
609 linux_attach (unsigned long pid
)
611 struct lwp_info
*lwp
;
613 linux_attach_lwp_1 (pid
, 1);
615 linux_add_process (pid
, 1);
619 /* Don't ignore the initial SIGSTOP if we just attached to this
620 process. It will be collected by wait shortly. */
621 lwp
= (struct lwp_info
*) find_inferior_id (&all_lwps
,
622 ptid_build (pid
, pid
, 0));
623 lwp
->stop_expected
= 0;
636 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
638 struct counter
*counter
= args
;
640 if (ptid_get_pid (entry
->id
) == counter
->pid
)
642 if (++counter
->count
> 1)
650 last_thread_of_process_p (struct thread_info
*thread
)
652 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
653 int pid
= ptid_get_pid (ptid
);
654 struct counter counter
= { pid
, 0 };
656 return (find_inferior (&all_threads
,
657 second_thread_of_pid_p
, &counter
) == NULL
);
660 /* Kill the inferior lwp. */
663 linux_kill_one_lwp (struct inferior_list_entry
*entry
, void *args
)
665 struct thread_info
*thread
= (struct thread_info
*) entry
;
666 struct lwp_info
*lwp
= get_thread_lwp (thread
);
668 int pid
= * (int *) args
;
670 if (ptid_get_pid (entry
->id
) != pid
)
673 /* We avoid killing the first thread here, because of a Linux kernel (at
674 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
675 the children get a chance to be reaped, it will remain a zombie
678 if (lwpid_of (lwp
) == pid
)
681 fprintf (stderr
, "lkop: is last of process %s\n",
682 target_pid_to_str (entry
->id
));
686 /* If we're killing a running inferior, make sure it is stopped
687 first, as PTRACE_KILL will not work otherwise. */
689 send_sigstop (&lwp
->head
);
693 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
695 /* Make sure it died. The loop is most likely unnecessary. */
696 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
697 } while (pid
> 0 && WIFSTOPPED (wstat
));
705 struct process_info
*process
;
706 struct lwp_info
*lwp
;
707 struct thread_info
*thread
;
711 process
= find_process_pid (pid
);
715 find_inferior (&all_threads
, linux_kill_one_lwp
, &pid
);
717 /* See the comment in linux_kill_one_lwp. We did not kill the first
718 thread in the list, so do so now. */
719 lwp
= find_lwp_pid (pid_to_ptid (pid
));
720 thread
= get_lwp_thread (lwp
);
723 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
724 lwpid_of (lwp
), pid
);
726 /* If we're killing a running inferior, make sure it is stopped
727 first, as PTRACE_KILL will not work otherwise. */
729 send_sigstop (&lwp
->head
);
733 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
735 /* Make sure it died. The loop is most likely unnecessary. */
736 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
737 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
740 linux_remove_process (process
, 0);
745 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
747 struct thread_info
*thread
= (struct thread_info
*) entry
;
748 struct lwp_info
*lwp
= get_thread_lwp (thread
);
749 int pid
= * (int *) args
;
751 if (ptid_get_pid (entry
->id
) != pid
)
754 /* If we're detaching from a running inferior, make sure it is
755 stopped first, as PTRACE_DETACH will not work otherwise. */
758 int lwpid
= lwpid_of (lwp
);
760 stopping_threads
= 1;
761 send_sigstop (&lwp
->head
);
763 /* If this detects a new thread through a clone event, the new
764 thread is appended to the end of the lwp list, so we'll
765 eventually detach from it. */
766 wait_for_sigstop (&lwp
->head
);
767 stopping_threads
= 0;
769 /* If LWP exits while we're trying to stop it, there's nothing
771 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
776 /* Make sure the process isn't stopped at a breakpoint that's
778 check_removed_breakpoint (lwp
);
780 /* If this process is stopped but is expecting a SIGSTOP, then make
781 sure we take care of that now. This isn't absolutely guaranteed
782 to collect the SIGSTOP, but is fairly likely to. */
783 if (lwp
->stop_expected
)
786 /* Clear stop_expected, so that the SIGSTOP will be reported. */
787 lwp
->stop_expected
= 0;
789 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
790 linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
793 /* Flush any pending changes to the process's registers. */
794 regcache_invalidate_one ((struct inferior_list_entry
*)
795 get_lwp_thread (lwp
));
797 /* Finally, let it resume. */
798 ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0, 0);
805 any_thread_of (struct inferior_list_entry
*entry
, void *args
)
809 if (ptid_get_pid (entry
->id
) == *pid_p
)
816 linux_detach (int pid
)
818 struct process_info
*process
;
820 process
= find_process_pid (pid
);
825 (struct thread_info
*) find_inferior (&all_threads
, any_thread_of
, &pid
);
827 delete_all_breakpoints ();
828 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
829 linux_remove_process (process
, 1);
837 struct process_info
*process
;
839 process
= find_process_pid (pid
);
844 ret
= my_waitpid (pid
, &status
, 0);
845 if (WIFEXITED (status
) || WIFSIGNALED (status
))
847 } while (ret
!= -1 || errno
!= ECHILD
);
850 /* Return nonzero if the given thread is still alive. */
852 linux_thread_alive (ptid_t ptid
)
854 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
856 /* We assume we always know if a thread exits. If a whole process
857 exited but we still haven't been able to report it to GDB, we'll
858 hold on to the last lwp of the dead process. */
865 /* Return nonzero if this process stopped at a breakpoint which
866 no longer appears to be inserted. Also adjust the PC
867 appropriately to resume where the breakpoint used to be. */
869 check_removed_breakpoint (struct lwp_info
*event_child
)
872 struct thread_info
*saved_inferior
;
874 if (event_child
->pending_is_breakpoint
== 0)
878 fprintf (stderr
, "Checking for breakpoint in lwp %ld.\n",
879 lwpid_of (event_child
));
881 saved_inferior
= current_inferior
;
882 current_inferior
= get_lwp_thread (event_child
);
884 stop_pc
= get_stop_pc ();
886 /* If the PC has changed since we stopped, then we shouldn't do
887 anything. This happens if, for instance, GDB handled the
888 decr_pc_after_break subtraction itself. */
889 if (stop_pc
!= event_child
->pending_stop_pc
)
892 fprintf (stderr
, "Ignoring, PC was changed. Old PC was 0x%08llx\n",
893 event_child
->pending_stop_pc
);
895 event_child
->pending_is_breakpoint
= 0;
896 current_inferior
= saved_inferior
;
900 /* If the breakpoint is still there, we will report hitting it. */
901 if ((*the_low_target
.breakpoint_at
) (stop_pc
))
904 fprintf (stderr
, "Ignoring, breakpoint is still present.\n");
905 current_inferior
= saved_inferior
;
910 fprintf (stderr
, "Removed breakpoint.\n");
912 /* For decr_pc_after_break targets, here is where we perform the
913 decrement. We go immediately from this function to resuming,
914 and can not safely call get_stop_pc () again. */
915 if (the_low_target
.set_pc
!= NULL
)
918 fprintf (stderr
, "Set pc to 0x%lx\n", (long) stop_pc
);
919 (*the_low_target
.set_pc
) (stop_pc
);
922 /* We consumed the pending SIGTRAP. */
923 event_child
->pending_is_breakpoint
= 0;
924 event_child
->status_pending_p
= 0;
925 event_child
->status_pending
= 0;
927 current_inferior
= saved_inferior
;
931 /* Return 1 if this lwp has an interesting status pending. This
932 function may silently resume an inferior lwp. */
934 status_pending_p (struct inferior_list_entry
*entry
, void *arg
)
936 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
937 ptid_t ptid
= * (ptid_t
*) arg
;
939 /* Check if we're only interested in events from a specific process
941 if (!ptid_equal (minus_one_ptid
, ptid
)
942 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
945 if (lwp
->status_pending_p
&& !lwp
->suspended
)
946 if (check_removed_breakpoint (lwp
))
948 /* This thread was stopped at a breakpoint, and the breakpoint
949 is now gone. We were told to continue (or step...) all threads,
950 so GDB isn't trying to single-step past this breakpoint.
951 So instead of reporting the old SIGTRAP, pretend we got to
952 the breakpoint just after it was removed instead of just
953 before; resume the process. */
954 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
958 return (lwp
->status_pending_p
&& !lwp
->suspended
);
962 same_lwp (struct inferior_list_entry
*entry
, void *data
)
964 ptid_t ptid
= *(ptid_t
*) data
;
967 if (ptid_get_lwp (ptid
) != 0)
968 lwp
= ptid_get_lwp (ptid
);
970 lwp
= ptid_get_pid (ptid
);
972 if (ptid_get_lwp (entry
->id
) == lwp
)
979 find_lwp_pid (ptid_t ptid
)
981 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
984 static struct lwp_info
*
985 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
988 int to_wait_for
= -1;
989 struct lwp_info
*child
= NULL
;
992 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
994 if (ptid_equal (ptid
, minus_one_ptid
))
995 to_wait_for
= -1; /* any child */
997 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1003 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1004 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1007 perror_with_name ("waitpid");
1010 && (!WIFSTOPPED (*wstatp
)
1011 || (WSTOPSIG (*wstatp
) != 32
1012 && WSTOPSIG (*wstatp
) != 33)))
1013 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1015 child
= find_lwp_pid (pid_to_ptid (ret
));
1017 /* If we didn't find a process, one of two things presumably happened:
1018 - A process we started and then detached from has exited. Ignore it.
1019 - A process we are controlling has forked and the new child's stop
1020 was reported to us by the kernel. Save its PID. */
1021 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1023 add_pid_to_list (&stopped_pids
, ret
);
1026 else if (child
== NULL
)
1030 child
->pending_is_breakpoint
= 0;
1032 child
->last_status
= *wstatp
;
1034 /* Architecture-specific setup after inferior is running.
1035 This needs to happen after we have attached to the inferior
1036 and it is stopped for the first time, but before we access
1037 any inferior registers. */
1040 the_low_target
.arch_setup ();
1041 #ifdef HAVE_LINUX_REGSETS
1042 memset (disabled_regsets
, 0, num_regsets
);
1048 && WIFSTOPPED (*wstatp
)
1049 && the_low_target
.get_pc
!= NULL
)
1051 struct thread_info
*saved_inferior
= current_inferior
;
1054 current_inferior
= (struct thread_info
*)
1055 find_inferior_id (&all_threads
, child
->head
.id
);
1056 pc
= (*the_low_target
.get_pc
) ();
1057 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1058 current_inferior
= saved_inferior
;
1064 /* Wait for an event from child PID. If PID is -1, wait for any
1065 child. Store the stop status through the status pointer WSTAT.
1066 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1067 event was found and OPTIONS contains WNOHANG. Return the PID of
1068 the stopped child otherwise. */
1071 linux_wait_for_event_1 (ptid_t ptid
, int *wstat
, int options
)
1074 struct lwp_info
*event_child
= NULL
;
1076 struct lwp_info
*requested_child
= NULL
;
1078 /* Check for a lwp with a pending status. */
1079 /* It is possible that the user changed the pending task's registers since
1080 it stopped. We correctly handle the change of PC if we hit a breakpoint
1081 (in check_removed_breakpoint); signals should be reported anyway. */
1083 if (ptid_equal (ptid
, minus_one_ptid
)
1084 || ptid_equal (pid_to_ptid (ptid_get_pid (ptid
)), ptid
))
1086 event_child
= (struct lwp_info
*)
1087 find_inferior (&all_lwps
, status_pending_p
, &ptid
);
1088 if (debug_threads
&& event_child
)
1089 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1093 requested_child
= find_lwp_pid (ptid
);
1094 if (requested_child
->status_pending_p
1095 && !check_removed_breakpoint (requested_child
))
1096 event_child
= requested_child
;
1099 if (event_child
!= NULL
)
1102 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1103 lwpid_of (event_child
), event_child
->status_pending
);
1104 *wstat
= event_child
->status_pending
;
1105 event_child
->status_pending_p
= 0;
1106 event_child
->status_pending
= 0;
1107 current_inferior
= get_lwp_thread (event_child
);
1108 return lwpid_of (event_child
);
1111 /* We only enter this loop if no process has a pending wait status. Thus
1112 any action taken in response to a wait status inside this loop is
1113 responding as soon as we detect the status, not after any pending
1117 event_child
= linux_wait_for_lwp (ptid
, wstat
, options
);
1119 if ((options
& WNOHANG
) && event_child
== NULL
)
1122 if (event_child
== NULL
)
1123 error ("event from unknown child");
1125 current_inferior
= get_lwp_thread (event_child
);
1127 /* Check for thread exit. */
1128 if (! WIFSTOPPED (*wstat
))
1131 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1133 /* If the last thread is exiting, just return. */
1134 if (last_thread_of_process_p (current_inferior
))
1137 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1138 lwpid_of (event_child
));
1139 return lwpid_of (event_child
);
1142 delete_lwp (event_child
);
1146 current_inferior
= (struct thread_info
*) all_threads
.head
;
1148 fprintf (stderr
, "Current inferior is now %ld\n",
1149 lwpid_of (get_thread_lwp (current_inferior
)));
1153 current_inferior
= NULL
;
1155 fprintf (stderr
, "Current inferior is now <NULL>\n");
1158 /* If we were waiting for this particular child to do something...
1159 well, it did something. */
1160 if (requested_child
!= NULL
)
1161 return lwpid_of (event_child
);
1163 /* Wait for a more interesting event. */
1167 if (event_child
->must_set_ptrace_flags
)
1169 ptrace (PTRACE_SETOPTIONS
, lwpid_of (event_child
),
1170 0, PTRACE_O_TRACECLONE
);
1171 event_child
->must_set_ptrace_flags
= 0;
1174 if (WIFSTOPPED (*wstat
)
1175 && WSTOPSIG (*wstat
) == SIGSTOP
1176 && event_child
->stop_expected
)
1179 fprintf (stderr
, "Expected stop.\n");
1180 event_child
->stop_expected
= 0;
1181 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
1185 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1186 && *wstat
>> 16 != 0)
1188 handle_extended_wait (event_child
, *wstat
);
1192 /* If GDB is not interested in this signal, don't stop other
1193 threads, and don't report it to GDB. Just resume the
1194 inferior right away. We do this for threading-related
1195 signals as well as any that GDB specifically requested we
1196 ignore. But never ignore SIGSTOP if we sent it ourselves,
1197 and do not ignore signals when stepping - they may require
1198 special handling to skip the signal handler. */
1199 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
1201 if (WIFSTOPPED (*wstat
)
1202 && !event_child
->stepping
1204 #ifdef USE_THREAD_DB
1205 (current_process ()->private->thread_db
!= NULL
1206 && (WSTOPSIG (*wstat
) == __SIGRTMIN
1207 || WSTOPSIG (*wstat
) == __SIGRTMIN
+ 1))
1210 (pass_signals
[target_signal_from_host (WSTOPSIG (*wstat
))]
1211 && (WSTOPSIG (*wstat
) != SIGSTOP
|| !stopping_threads
))))
1213 siginfo_t info
, *info_p
;
1216 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
1217 WSTOPSIG (*wstat
), lwpid_of (event_child
));
1219 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
1223 linux_resume_one_lwp (event_child
,
1224 event_child
->stepping
,
1225 WSTOPSIG (*wstat
), info_p
);
1229 /* If this event was not handled above, and is not a SIGTRAP, report
1231 if (!WIFSTOPPED (*wstat
) || WSTOPSIG (*wstat
) != SIGTRAP
)
1232 return lwpid_of (event_child
);
1234 /* If this target does not support breakpoints, we simply report the
1235 SIGTRAP; it's of no concern to us. */
1236 if (the_low_target
.get_pc
== NULL
)
1237 return lwpid_of (event_child
);
1239 stop_pc
= get_stop_pc ();
1241 /* bp_reinsert will only be set if we were single-stepping.
1242 Notice that we will resume the process after hitting
1243 a gdbserver breakpoint; single-stepping to/over one
1244 is not supported (yet). */
1245 if (event_child
->bp_reinsert
!= 0)
1248 fprintf (stderr
, "Reinserted breakpoint.\n");
1249 reinsert_breakpoint (event_child
->bp_reinsert
);
1250 event_child
->bp_reinsert
= 0;
1252 /* Clear the single-stepping flag and SIGTRAP as we resume. */
1253 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1257 bp_status
= check_breakpoints (stop_pc
);
1262 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
1264 /* We hit one of our own breakpoints. We mark it as a pending
1265 breakpoint, so that check_removed_breakpoint () will do the PC
1266 adjustment for us at the appropriate time. */
1267 event_child
->pending_is_breakpoint
= 1;
1268 event_child
->pending_stop_pc
= stop_pc
;
1270 /* We may need to put the breakpoint back. We continue in the event
1271 loop instead of simply replacing the breakpoint right away,
1272 in order to not lose signals sent to the thread that hit the
1273 breakpoint. Unfortunately this increases the window where another
1274 thread could sneak past the removed breakpoint. For the current
1275 use of server-side breakpoints (thread creation) this is
1276 acceptable; but it needs to be considered before this breakpoint
1277 mechanism can be used in more general ways. For some breakpoints
1278 it may be necessary to stop all other threads, but that should
1279 be avoided where possible.
1281 If breakpoint_reinsert_addr is NULL, that means that we can
1282 use PTRACE_SINGLESTEP on this platform. Uninsert the breakpoint,
1283 mark it for reinsertion, and single-step.
1285 Otherwise, call the target function to figure out where we need
1286 our temporary breakpoint, create it, and continue executing this
1289 /* NOTE: we're lifting breakpoints in non-stop mode. This
1290 is currently only used for thread event breakpoints, so
1291 it isn't that bad as long as we have PTRACE_EVENT_CLONE
1294 /* No need to reinsert. */
1295 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1296 else if (the_low_target
.breakpoint_reinsert_addr
== NULL
)
1298 event_child
->bp_reinsert
= stop_pc
;
1299 uninsert_breakpoint (stop_pc
);
1300 linux_resume_one_lwp (event_child
, 1, 0, NULL
);
1304 reinsert_breakpoint_by_bp
1305 (stop_pc
, (*the_low_target
.breakpoint_reinsert_addr
) ());
1306 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1313 fprintf (stderr
, "Hit a non-gdbserver breakpoint.\n");
1315 /* If we were single-stepping, we definitely want to report the
1316 SIGTRAP. Although the single-step operation has completed,
1317 do not clear clear the stepping flag yet; we need to check it
1318 in wait_for_sigstop. */
1319 if (event_child
->stepping
)
1320 return lwpid_of (event_child
);
1322 /* A SIGTRAP that we can't explain. It may have been a breakpoint.
1323 Check if it is a breakpoint, and if so mark the process information
1324 accordingly. This will handle both the necessary fiddling with the
1325 PC on decr_pc_after_break targets and suppressing extra threads
1326 hitting a breakpoint if two hit it at once and then GDB removes it
1327 after the first is reported. Arguably it would be better to report
1328 multiple threads hitting breakpoints simultaneously, but the current
1329 remote protocol does not allow this. */
1330 if ((*the_low_target
.breakpoint_at
) (stop_pc
))
1332 event_child
->pending_is_breakpoint
= 1;
1333 event_child
->pending_stop_pc
= stop_pc
;
1336 return lwpid_of (event_child
);
1344 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1348 if (ptid_is_pid (ptid
))
1350 /* A request to wait for a specific tgid. This is not possible
1351 with waitpid, so instead, we wait for any child, and leave
1352 children we're not interested in right now with a pending
1353 status to report later. */
1354 wait_ptid
= minus_one_ptid
;
1363 event_pid
= linux_wait_for_event_1 (wait_ptid
, wstat
, options
);
1366 && ptid_is_pid (ptid
) && ptid_get_pid (ptid
) != event_pid
)
1368 struct lwp_info
*event_child
= find_lwp_pid (pid_to_ptid (event_pid
));
1370 if (! WIFSTOPPED (*wstat
))
1371 mark_lwp_dead (event_child
, *wstat
);
1374 event_child
->status_pending_p
= 1;
1375 event_child
->status_pending
= *wstat
;
1383 /* Wait for process, returns status. */
1386 linux_wait_1 (ptid_t ptid
,
1387 struct target_waitstatus
*ourstatus
, int target_options
)
1390 struct thread_info
*thread
= NULL
;
1391 struct lwp_info
*lwp
= NULL
;
1395 /* Translate generic target options into linux options. */
1397 if (target_options
& TARGET_WNOHANG
)
1401 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
1403 /* If we were only supposed to resume one thread, only wait for
1404 that thread - if it's still alive. If it died, however - which
1405 can happen if we're coming from the thread death case below -
1406 then we need to make sure we restart the other threads. We could
1407 pick a thread at random or restart all; restarting all is less
1410 && !ptid_equal (cont_thread
, null_ptid
)
1411 && !ptid_equal (cont_thread
, minus_one_ptid
))
1413 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
1416 /* No stepping, no signal - unless one is pending already, of course. */
1419 struct thread_resume resume_info
;
1420 resume_info
.thread
= minus_one_ptid
;
1421 resume_info
.kind
= resume_continue
;
1422 resume_info
.sig
= 0;
1423 linux_resume (&resume_info
, 1);
1429 pid
= linux_wait_for_event (ptid
, &w
, options
);
1430 if (pid
== 0) /* only if TARGET_WNOHANG */
1433 lwp
= get_thread_lwp (current_inferior
);
1435 /* If we are waiting for a particular child, and it exited,
1436 linux_wait_for_event will return its exit status. Similarly if
1437 the last child exited. If this is not the last child, however,
1438 do not report it as exited until there is a 'thread exited' response
1439 available in the remote protocol. Instead, just wait for another event.
1440 This should be safe, because if the thread crashed we will already
1441 have reported the termination signal to GDB; that should stop any
1442 in-progress stepping operations, etc.
1444 Report the exit status of the last thread to exit. This matches
1445 LinuxThreads' behavior. */
1447 if (last_thread_of_process_p (current_inferior
))
1449 if (WIFEXITED (w
) || WIFSIGNALED (w
))
1451 int pid
= pid_of (lwp
);
1452 struct process_info
*process
= find_process_pid (pid
);
1455 linux_remove_process (process
, 0);
1457 current_inferior
= NULL
;
1461 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
1462 ourstatus
->value
.integer
= WEXITSTATUS (w
);
1465 fprintf (stderr
, "\nChild exited with retcode = %x \n", WEXITSTATUS (w
));
1469 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
1470 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
1473 fprintf (stderr
, "\nChild terminated with signal = %x \n", WTERMSIG (w
));
1477 return pid_to_ptid (pid
);
1482 if (!WIFSTOPPED (w
))
1486 /* In all-stop, stop all threads. Be careful to only do this if
1487 we're about to report an event to GDB. */
1491 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
1493 if (lwp
->suspended
&& WSTOPSIG (w
) == SIGSTOP
)
1495 /* A thread that has been requested to stop by GDB with vCont;t,
1496 and it stopped cleanly, so report as SIG0. The use of
1497 SIGSTOP is an implementation detail. */
1498 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
1500 else if (lwp
->suspended
&& WSTOPSIG (w
) != SIGSTOP
)
1502 /* A thread that has been requested to stop by GDB with vCont;t,
1503 but, it stopped for other reasons. Set stop_expected so the
1504 pending SIGSTOP is ignored and the LWP is resumed. */
1505 lwp
->stop_expected
= 1;
1506 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
1510 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
1514 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
1515 target_pid_to_str (lwp
->head
.id
),
1517 ourstatus
->value
.sig
);
1519 return lwp
->head
.id
;
1522 /* Get rid of any pending event in the pipe. */
1524 async_file_flush (void)
1530 ret
= read (linux_event_pipe
[0], &buf
, 1);
1531 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
1534 /* Put something in the pipe, so the event loop wakes up. */
1536 async_file_mark (void)
1540 async_file_flush ();
1543 ret
= write (linux_event_pipe
[1], "+", 1);
1544 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
1546 /* Ignore EAGAIN. If the pipe is full, the event loop will already
1547 be awakened anyway. */
1551 linux_wait (ptid_t ptid
,
1552 struct target_waitstatus
*ourstatus
, int target_options
)
1557 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
1559 /* Flush the async file first. */
1560 if (target_is_async_p ())
1561 async_file_flush ();
1563 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
1565 /* If at least one stop was reported, there may be more. A single
1566 SIGCHLD can signal more than one child stop. */
1567 if (target_is_async_p ()
1568 && (target_options
& TARGET_WNOHANG
) != 0
1569 && !ptid_equal (event_ptid
, null_ptid
))
1575 /* Send a signal to an LWP. For LinuxThreads, kill is enough; however, if
1576 thread groups are in use, we need to use tkill. */
1579 kill_lwp (unsigned long lwpid
, int signo
)
1581 static int tkill_failed
;
1588 int ret
= syscall (SYS_tkill
, lwpid
, signo
);
1589 if (errno
!= ENOSYS
)
1596 return kill (lwpid
, signo
);
1600 send_sigstop (struct inferior_list_entry
*entry
)
1602 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1608 pid
= lwpid_of (lwp
);
1610 /* If we already have a pending stop signal for this process, don't
1612 if (lwp
->stop_expected
)
1615 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
1617 /* We clear the stop_expected flag so that wait_for_sigstop
1618 will receive the SIGSTOP event (instead of silently resuming and
1619 waiting again). It'll be reset below. */
1620 lwp
->stop_expected
= 0;
1625 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
1627 kill_lwp (pid
, SIGSTOP
);
1631 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
1633 /* It's dead, really. */
1636 /* Store the exit status for later. */
1637 lwp
->status_pending_p
= 1;
1638 lwp
->status_pending
= wstat
;
1640 /* So that check_removed_breakpoint doesn't try to figure out if
1641 this is stopped at a breakpoint. */
1642 lwp
->pending_is_breakpoint
= 0;
1644 /* Prevent trying to stop it. */
1647 /* No further stops are expected from a dead lwp. */
1648 lwp
->stop_expected
= 0;
1652 wait_for_sigstop (struct inferior_list_entry
*entry
)
1654 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1655 struct thread_info
*saved_inferior
;
1663 saved_inferior
= current_inferior
;
1664 if (saved_inferior
!= NULL
)
1665 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
1667 saved_tid
= null_ptid
; /* avoid bogus unused warning */
1669 ptid
= lwp
->head
.id
;
1671 linux_wait_for_event (ptid
, &wstat
, __WALL
);
1673 /* If we stopped with a non-SIGSTOP signal, save it for later
1674 and record the pending SIGSTOP. If the process exited, just
1676 if (WIFSTOPPED (wstat
)
1677 && WSTOPSIG (wstat
) != SIGSTOP
)
1680 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
1681 lwpid_of (lwp
), wstat
);
1683 /* Do not leave a pending single-step finish to be reported to
1684 the client. The client will give us a new action for this
1685 thread, possibly a continue request --- otherwise, the client
1686 would consider this pending SIGTRAP reported later a spurious
1688 if (WSTOPSIG (wstat
) == SIGTRAP
1690 && !linux_stopped_by_watchpoint ())
1693 fprintf (stderr
, " single-step SIGTRAP ignored\n");
1697 lwp
->status_pending_p
= 1;
1698 lwp
->status_pending
= wstat
;
1700 lwp
->stop_expected
= 1;
1702 else if (!WIFSTOPPED (wstat
))
1705 fprintf (stderr
, "Process %ld exited while stopping LWPs\n",
1708 /* Leave this status pending for the next time we're able to
1709 report it. In the mean time, we'll report this lwp as dead
1710 to GDB, so GDB doesn't try to read registers and memory from
1712 mark_lwp_dead (lwp
, wstat
);
1715 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
1716 current_inferior
= saved_inferior
;
1720 fprintf (stderr
, "Previously current thread died.\n");
1724 /* We can't change the current inferior behind GDB's back,
1725 otherwise, a subsequent command may apply to the wrong
1727 current_inferior
= NULL
;
1731 /* Set a valid thread as current. */
1732 set_desired_inferior (0);
1738 stop_all_lwps (void)
1740 stopping_threads
= 1;
1741 for_each_inferior (&all_lwps
, send_sigstop
);
1742 for_each_inferior (&all_lwps
, wait_for_sigstop
);
1743 stopping_threads
= 0;
1746 /* Resume execution of the inferior process.
1747 If STEP is nonzero, single-step it.
1748 If SIGNAL is nonzero, give it that signal. */
1751 linux_resume_one_lwp (struct lwp_info
*lwp
,
1752 int step
, int signal
, siginfo_t
*info
)
1754 struct thread_info
*saved_inferior
;
1756 if (lwp
->stopped
== 0)
1759 /* If we have pending signals or status, and a new signal, enqueue the
1760 signal. Also enqueue the signal if we are waiting to reinsert a
1761 breakpoint; it will be picked up again below. */
1763 && (lwp
->status_pending_p
|| lwp
->pending_signals
!= NULL
1764 || lwp
->bp_reinsert
!= 0))
1766 struct pending_signals
*p_sig
;
1767 p_sig
= xmalloc (sizeof (*p_sig
));
1768 p_sig
->prev
= lwp
->pending_signals
;
1769 p_sig
->signal
= signal
;
1771 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1773 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
1774 lwp
->pending_signals
= p_sig
;
1777 if (lwp
->status_pending_p
&& !check_removed_breakpoint (lwp
))
1780 saved_inferior
= current_inferior
;
1781 current_inferior
= get_lwp_thread (lwp
);
1784 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
1785 lwpid_of (lwp
), step
? "step" : "continue", signal
,
1786 lwp
->stop_expected
? "expected" : "not expected");
1788 /* This bit needs some thinking about. If we get a signal that
1789 we must report while a single-step reinsert is still pending,
1790 we often end up resuming the thread. It might be better to
1791 (ew) allow a stack of pending events; then we could be sure that
1792 the reinsert happened right away and not lose any signals.
1794 Making this stack would also shrink the window in which breakpoints are
1795 uninserted (see comment in linux_wait_for_lwp) but not enough for
1796 complete correctness, so it won't solve that problem. It may be
1797 worthwhile just to solve this one, however. */
1798 if (lwp
->bp_reinsert
!= 0)
1801 fprintf (stderr
, " pending reinsert at %08lx", (long)lwp
->bp_reinsert
);
1803 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
1806 /* Postpone any pending signal. It was enqueued above. */
1810 check_removed_breakpoint (lwp
);
1812 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
1814 CORE_ADDR pc
= (*the_low_target
.get_pc
) ();
1815 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
1818 /* If we have pending signals, consume one unless we are trying to reinsert
1820 if (lwp
->pending_signals
!= NULL
&& lwp
->bp_reinsert
== 0)
1822 struct pending_signals
**p_sig
;
1824 p_sig
= &lwp
->pending_signals
;
1825 while ((*p_sig
)->prev
!= NULL
)
1826 p_sig
= &(*p_sig
)->prev
;
1828 signal
= (*p_sig
)->signal
;
1829 if ((*p_sig
)->info
.si_signo
!= 0)
1830 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
1836 if (the_low_target
.prepare_to_resume
!= NULL
)
1837 the_low_target
.prepare_to_resume (lwp
);
1839 regcache_invalidate_one ((struct inferior_list_entry
*)
1840 get_lwp_thread (lwp
));
1843 lwp
->stepping
= step
;
1844 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0, signal
);
1846 current_inferior
= saved_inferior
;
1849 /* ESRCH from ptrace either means that the thread was already
1850 running (an error) or that it is gone (a race condition). If
1851 it's gone, we will get a notification the next time we wait,
1852 so we can ignore the error. We could differentiate these
1853 two, but it's tricky without waiting; the thread still exists
1854 as a zombie, so sending it signal 0 would succeed. So just
1859 perror_with_name ("ptrace");
1863 struct thread_resume_array
1865 struct thread_resume
*resume
;
1869 /* This function is called once per thread. We look up the thread
1870 in RESUME_PTR, and mark the thread with a pointer to the appropriate
1873 This algorithm is O(threads * resume elements), but resume elements
1874 is small (and will remain small at least until GDB supports thread
1877 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
1879 struct lwp_info
*lwp
;
1880 struct thread_info
*thread
;
1882 struct thread_resume_array
*r
;
1884 thread
= (struct thread_info
*) entry
;
1885 lwp
= get_thread_lwp (thread
);
1888 for (ndx
= 0; ndx
< r
->n
; ndx
++)
1890 ptid_t ptid
= r
->resume
[ndx
].thread
;
1891 if (ptid_equal (ptid
, minus_one_ptid
)
1892 || ptid_equal (ptid
, entry
->id
)
1893 || (ptid_is_pid (ptid
)
1894 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
1895 || (ptid_get_lwp (ptid
) == -1
1896 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
1898 lwp
->resume
= &r
->resume
[ndx
];
1903 /* No resume action for this thread. */
1910 /* Set *FLAG_P if this lwp has an interesting status pending. */
1912 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
1914 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1916 /* LWPs which will not be resumed are not interesting, because
1917 we might not wait for them next time through linux_wait. */
1918 if (lwp
->resume
== NULL
)
1921 /* If this thread has a removed breakpoint, we won't have any
1922 events to report later, so check now. check_removed_breakpoint
1923 may clear status_pending_p. We avoid calling check_removed_breakpoint
1924 for any thread that we are not otherwise going to resume - this
1925 lets us preserve stopped status when two threads hit a breakpoint.
1926 GDB removes the breakpoint to single-step a particular thread
1927 past it, then re-inserts it and resumes all threads. We want
1928 to report the second thread without resuming it in the interim. */
1929 if (lwp
->status_pending_p
)
1930 check_removed_breakpoint (lwp
);
1932 if (lwp
->status_pending_p
)
1933 * (int *) flag_p
= 1;
1938 /* This function is called once per thread. We check the thread's resume
1939 request, which will tell us whether to resume, step, or leave the thread
1940 stopped; and what signal, if any, it should be sent.
1942 For threads which we aren't explicitly told otherwise, we preserve
1943 the stepping flag; this is used for stepping over gdbserver-placed
1946 If pending_flags was set in any thread, we queue any needed
1947 signals, since we won't actually resume. We already have a pending
1948 event to report, so we don't need to preserve any step requests;
1949 they should be re-issued if necessary. */
1952 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
1954 struct lwp_info
*lwp
;
1955 struct thread_info
*thread
;
1957 int pending_flag
= * (int *) arg
;
1959 thread
= (struct thread_info
*) entry
;
1960 lwp
= get_thread_lwp (thread
);
1962 if (lwp
->resume
== NULL
)
1965 if (lwp
->resume
->kind
== resume_stop
)
1968 fprintf (stderr
, "suspending LWP %ld\n", lwpid_of (lwp
));
1973 fprintf (stderr
, "running -> suspending LWP %ld\n", lwpid_of (lwp
));
1976 send_sigstop (&lwp
->head
);
1983 fprintf (stderr
, "already stopped/suspended LWP %ld\n",
1986 fprintf (stderr
, "already stopped/not suspended LWP %ld\n",
1990 /* Make sure we leave the LWP suspended, so we don't try to
1991 resume it without GDB telling us to. FIXME: The LWP may
1992 have been stopped in an internal event that was not meant
1993 to be notified back to GDB (e.g., gdbserver breakpoint),
1994 so we should be reporting a stop event in that case
1999 /* For stop requests, we're done. */
2006 /* If this thread which is about to be resumed has a pending status,
2007 then don't resume any threads - we can just report the pending
2008 status. Make sure to queue any signals that would otherwise be
2009 sent. In all-stop mode, we do this decision based on if *any*
2010 thread has a pending status. */
2012 resume_status_pending_p (&lwp
->head
, &pending_flag
);
2017 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
2019 if (ptid_equal (lwp
->resume
->thread
, minus_one_ptid
)
2021 && lwp
->pending_is_breakpoint
)
2024 step
= (lwp
->resume
->kind
== resume_step
);
2026 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
2031 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
2033 /* If we have a new signal, enqueue the signal. */
2034 if (lwp
->resume
->sig
!= 0)
2036 struct pending_signals
*p_sig
;
2037 p_sig
= xmalloc (sizeof (*p_sig
));
2038 p_sig
->prev
= lwp
->pending_signals
;
2039 p_sig
->signal
= lwp
->resume
->sig
;
2040 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
2042 /* If this is the same signal we were previously stopped by,
2043 make sure to queue its siginfo. We can ignore the return
2044 value of ptrace; if it fails, we'll skip
2045 PTRACE_SETSIGINFO. */
2046 if (WIFSTOPPED (lwp
->last_status
)
2047 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
2048 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
2050 lwp
->pending_signals
= p_sig
;
2059 linux_resume (struct thread_resume
*resume_info
, size_t n
)
2062 struct thread_resume_array array
= { resume_info
, n
};
2064 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
2066 /* If there is a thread which would otherwise be resumed, which
2067 has a pending status, then don't resume any threads - we can just
2068 report the pending status. Make sure to queue any signals
2069 that would otherwise be sent. In non-stop mode, we'll apply this
2070 logic to each thread individually. */
2073 find_inferior (&all_lwps
, resume_status_pending_p
, &pending_flag
);
2078 fprintf (stderr
, "Not resuming, pending status\n");
2080 fprintf (stderr
, "Resuming, no pending status\n");
2083 find_inferior (&all_threads
, linux_resume_one_thread
, &pending_flag
);
2086 #ifdef HAVE_LINUX_USRREGS
2089 register_addr (int regnum
)
2093 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
2094 error ("Invalid register number %d.", regnum
);
2096 addr
= the_low_target
.regmap
[regnum
];
2101 /* Fetch one register. */
2103 fetch_register (int regno
)
2110 if (regno
>= the_low_target
.num_regs
)
2112 if ((*the_low_target
.cannot_fetch_register
) (regno
))
2115 regaddr
= register_addr (regno
);
2119 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2120 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2121 & - sizeof (PTRACE_XFER_TYPE
));
2122 buf
= alloca (size
);
2123 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
2126 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
2127 ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_ARG3_TYPE
) regaddr
, 0);
2128 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
2131 /* Warning, not error, in case we are attached; sometimes the
2132 kernel doesn't let us at the registers. */
2133 char *err
= strerror (errno
);
2134 char *msg
= alloca (strlen (err
) + 128);
2135 sprintf (msg
, "reading register %d: %s", regno
, err
);
2141 if (the_low_target
.supply_ptrace_register
)
2142 the_low_target
.supply_ptrace_register (regno
, buf
);
2144 supply_register (regno
, buf
);
2149 /* Fetch all registers, or just one, from the child process. */
2151 usr_fetch_inferior_registers (int regno
)
2154 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
2155 fetch_register (regno
);
2157 fetch_register (regno
);
2160 /* Store our register values back into the inferior.
2161 If REGNO is -1, do this for all registers.
2162 Otherwise, REGNO specifies which register (so we can save time). */
2164 usr_store_inferior_registers (int regno
)
2173 if (regno
>= the_low_target
.num_regs
)
2176 if ((*the_low_target
.cannot_store_register
) (regno
) == 1)
2179 regaddr
= register_addr (regno
);
2183 size
= (register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2184 & - sizeof (PTRACE_XFER_TYPE
);
2185 buf
= alloca (size
);
2186 memset (buf
, 0, size
);
2188 if (the_low_target
.collect_ptrace_register
)
2189 the_low_target
.collect_ptrace_register (regno
, buf
);
2191 collect_register (regno
, buf
);
2193 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2194 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
2197 ptrace (PTRACE_POKEUSER
, pid
, (PTRACE_ARG3_TYPE
) regaddr
,
2198 *(PTRACE_XFER_TYPE
*) (buf
+ i
));
2201 /* At this point, ESRCH should mean the process is
2202 already gone, in which case we simply ignore attempts
2203 to change its registers. See also the related
2204 comment in linux_resume_one_lwp. */
2208 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
2210 char *err
= strerror (errno
);
2211 char *msg
= alloca (strlen (err
) + 128);
2212 sprintf (msg
, "writing register %d: %s",
2218 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
2222 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
2223 usr_store_inferior_registers (regno
);
2225 #endif /* HAVE_LINUX_USRREGS */
2229 #ifdef HAVE_LINUX_REGSETS
2232 regsets_fetch_inferior_registers ()
2234 struct regset_info
*regset
;
2235 int saw_general_regs
= 0;
2238 regset
= target_regsets
;
2240 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2241 while (regset
->size
>= 0)
2246 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
2252 buf
= xmalloc (regset
->size
);
2254 res
= ptrace (regset
->get_request
, pid
, 0, buf
);
2256 res
= ptrace (regset
->get_request
, pid
, buf
, 0);
2262 /* If we get EIO on a regset, do not try it again for
2264 disabled_regsets
[regset
- target_regsets
] = 1;
2271 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
2276 else if (regset
->type
== GENERAL_REGS
)
2277 saw_general_regs
= 1;
2278 regset
->store_function (buf
);
2282 if (saw_general_regs
)
2289 regsets_store_inferior_registers ()
2291 struct regset_info
*regset
;
2292 int saw_general_regs
= 0;
2295 regset
= target_regsets
;
2297 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2298 while (regset
->size
>= 0)
2303 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
2309 buf
= xmalloc (regset
->size
);
2311 /* First fill the buffer with the current register set contents,
2312 in case there are any items in the kernel's regset that are
2313 not in gdbserver's regcache. */
2315 res
= ptrace (regset
->get_request
, pid
, 0, buf
);
2317 res
= ptrace (regset
->get_request
, pid
, buf
, 0);
2322 /* Then overlay our cached registers on that. */
2323 regset
->fill_function (buf
);
2325 /* Only now do we write the register set. */
2327 res
= ptrace (regset
->set_request
, pid
, 0, buf
);
2329 res
= ptrace (regset
->set_request
, pid
, buf
, 0);
2337 /* If we get EIO on a regset, do not try it again for
2339 disabled_regsets
[regset
- target_regsets
] = 1;
2343 else if (errno
== ESRCH
)
2345 /* At this point, ESRCH should mean the process is
2346 already gone, in which case we simply ignore attempts
2347 to change its registers. See also the related
2348 comment in linux_resume_one_lwp. */
2354 perror ("Warning: ptrace(regsets_store_inferior_registers)");
2357 else if (regset
->type
== GENERAL_REGS
)
2358 saw_general_regs
= 1;
2362 if (saw_general_regs
)
2369 #endif /* HAVE_LINUX_REGSETS */
2373 linux_fetch_registers (int regno
)
2375 #ifdef HAVE_LINUX_REGSETS
2376 if (regsets_fetch_inferior_registers () == 0)
2379 #ifdef HAVE_LINUX_USRREGS
2380 usr_fetch_inferior_registers (regno
);
2385 linux_store_registers (int regno
)
2387 #ifdef HAVE_LINUX_REGSETS
2388 if (regsets_store_inferior_registers () == 0)
2391 #ifdef HAVE_LINUX_USRREGS
2392 usr_store_inferior_registers (regno
);
2397 /* Copy LEN bytes from inferior's memory starting at MEMADDR
2398 to debugger memory starting at MYADDR. */
2401 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
2404 /* Round starting address down to longword boundary. */
2405 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
2406 /* Round ending address up; get number of longwords that makes. */
2408 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2409 / sizeof (PTRACE_XFER_TYPE
);
2410 /* Allocate buffer of that many longwords. */
2411 register PTRACE_XFER_TYPE
*buffer
2412 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
2415 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2417 /* Try using /proc. Don't bother for one word. */
2418 if (len
>= 3 * sizeof (long))
2420 /* We could keep this file open and cache it - possibly one per
2421 thread. That requires some juggling, but is even faster. */
2422 sprintf (filename
, "/proc/%d/mem", pid
);
2423 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
2427 /* If pread64 is available, use it. It's faster if the kernel
2428 supports it (only one syscall), and it's 64-bit safe even on
2429 32-bit platforms (for instance, SPARC debugging a SPARC64
2432 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
2434 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, myaddr
, len
) != len
)
2446 /* Read all the longwords */
2447 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
2450 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
, (PTRACE_ARG3_TYPE
) addr
, 0);
2455 /* Copy appropriate bytes out of the buffer. */
2457 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
2463 /* Copy LEN bytes of data from debugger memory at MYADDR
2464 to inferior's memory at MEMADDR.
2465 On failure (cannot write the inferior)
2466 returns the value of errno. */
2469 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
2472 /* Round starting address down to longword boundary. */
2473 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
2474 /* Round ending address up; get number of longwords that makes. */
2476 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1) / sizeof (PTRACE_XFER_TYPE
);
2477 /* Allocate buffer of that many longwords. */
2478 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
2479 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2483 /* Dump up to four bytes. */
2484 unsigned int val
= * (unsigned int *) myaddr
;
2490 val
= val
& 0xffffff;
2491 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
2492 val
, (long)memaddr
);
2495 /* Fill start and end extra bytes of buffer with existing memory data. */
2497 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
, (PTRACE_ARG3_TYPE
) addr
, 0);
2502 = ptrace (PTRACE_PEEKTEXT
, pid
,
2503 (PTRACE_ARG3_TYPE
) (addr
+ (count
- 1)
2504 * sizeof (PTRACE_XFER_TYPE
)),
2508 /* Copy data to be written over corresponding part of buffer */
2510 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)), myaddr
, len
);
2512 /* Write the entire buffer. */
2514 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
2517 ptrace (PTRACE_POKETEXT
, pid
, (PTRACE_ARG3_TYPE
) addr
, buffer
[i
]);
2525 static int linux_supports_tracefork_flag
;
2527 /* Helper functions for linux_test_for_tracefork, called via clone (). */
2530 linux_tracefork_grandchild (void *arg
)
2535 #define STACK_SIZE 4096
2538 linux_tracefork_child (void *arg
)
2540 ptrace (PTRACE_TRACEME
, 0, 0, 0);
2541 kill (getpid (), SIGSTOP
);
2543 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
2544 CLONE_VM
| SIGCHLD
, NULL
);
2546 clone (linux_tracefork_grandchild
, arg
+ STACK_SIZE
,
2547 CLONE_VM
| SIGCHLD
, NULL
);
2552 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
2553 sure that we can enable the option, and that it had the desired
2557 linux_test_for_tracefork (void)
2559 int child_pid
, ret
, status
;
2561 char *stack
= xmalloc (STACK_SIZE
* 4);
2563 linux_supports_tracefork_flag
= 0;
2565 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
2567 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
2568 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
2570 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
2571 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
2573 if (child_pid
== -1)
2574 perror_with_name ("clone");
2576 ret
= my_waitpid (child_pid
, &status
, 0);
2578 perror_with_name ("waitpid");
2579 else if (ret
!= child_pid
)
2580 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
2581 if (! WIFSTOPPED (status
))
2582 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
2584 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0, PTRACE_O_TRACEFORK
);
2587 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
2590 warning ("linux_test_for_tracefork: failed to kill child");
2594 ret
= my_waitpid (child_pid
, &status
, 0);
2595 if (ret
!= child_pid
)
2596 warning ("linux_test_for_tracefork: failed to wait for killed child");
2597 else if (!WIFSIGNALED (status
))
2598 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
2599 "killed child", status
);
2604 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
2606 warning ("linux_test_for_tracefork: failed to resume child");
2608 ret
= my_waitpid (child_pid
, &status
, 0);
2610 if (ret
== child_pid
&& WIFSTOPPED (status
)
2611 && status
>> 16 == PTRACE_EVENT_FORK
)
2614 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
2615 if (ret
== 0 && second_pid
!= 0)
2619 linux_supports_tracefork_flag
= 1;
2620 my_waitpid (second_pid
, &second_status
, 0);
2621 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
2623 warning ("linux_test_for_tracefork: failed to kill second child");
2624 my_waitpid (second_pid
, &status
, 0);
2628 warning ("linux_test_for_tracefork: unexpected result from waitpid "
2629 "(%d, status 0x%x)", ret
, status
);
2633 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
2635 warning ("linux_test_for_tracefork: failed to kill child");
2636 my_waitpid (child_pid
, &status
, 0);
2638 while (WIFSTOPPED (status
));
2645 linux_look_up_symbols (void)
2647 #ifdef USE_THREAD_DB
2648 struct process_info
*proc
= current_process ();
2650 if (proc
->private->thread_db
!= NULL
)
2653 thread_db_init (!linux_supports_tracefork_flag
);
2658 linux_request_interrupt (void)
2660 extern unsigned long signal_pid
;
2662 if (!ptid_equal (cont_thread
, null_ptid
)
2663 && !ptid_equal (cont_thread
, minus_one_ptid
))
2665 struct lwp_info
*lwp
;
2668 lwp
= get_thread_lwp (current_inferior
);
2669 lwpid
= lwpid_of (lwp
);
2670 kill_lwp (lwpid
, SIGINT
);
2673 kill_lwp (signal_pid
, SIGINT
);
2676 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
2677 to debugger memory starting at MYADDR. */
2680 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
2682 char filename
[PATH_MAX
];
2684 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2686 snprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
2688 fd
= open (filename
, O_RDONLY
);
2692 if (offset
!= (CORE_ADDR
) 0
2693 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
2696 n
= read (fd
, myaddr
, len
);
2703 /* These breakpoint and watchpoint related wrapper functions simply
2704 pass on the function call if the target has registered a
2705 corresponding function. */
2708 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
2710 if (the_low_target
.insert_point
!= NULL
)
2711 return the_low_target
.insert_point (type
, addr
, len
);
2713 /* Unsupported (see target.h). */
2718 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
2720 if (the_low_target
.remove_point
!= NULL
)
2721 return the_low_target
.remove_point (type
, addr
, len
);
2723 /* Unsupported (see target.h). */
2728 linux_stopped_by_watchpoint (void)
2730 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2731 return the_low_target
.stopped_by_watchpoint ();
2737 linux_stopped_data_address (void)
2739 if (the_low_target
.stopped_data_address
!= NULL
)
2740 return the_low_target
.stopped_data_address ();
2745 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
2746 #if defined(__mcoldfire__)
2747 /* These should really be defined in the kernel's ptrace.h header. */
2748 #define PT_TEXT_ADDR 49*4
2749 #define PT_DATA_ADDR 50*4
2750 #define PT_TEXT_END_ADDR 51*4
2753 /* Under uClinux, programs are loaded at non-zero offsets, which we need
2754 to tell gdb about. */
2757 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
2759 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
2760 unsigned long text
, text_end
, data
;
2761 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2765 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
2766 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
2767 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
2771 /* Both text and data offsets produced at compile-time (and so
2772 used by gdb) are relative to the beginning of the program,
2773 with the data segment immediately following the text segment.
2774 However, the actual runtime layout in memory may put the data
2775 somewhere else, so when we send gdb a data base-address, we
2776 use the real data base address and subtract the compile-time
2777 data base-address from it (which is just the length of the
2778 text segment). BSS immediately follows data in both
2781 *data_p
= data
- (text_end
- text
);
2791 linux_qxfer_osdata (const char *annex
,
2792 unsigned char *readbuf
, unsigned const char *writebuf
,
2793 CORE_ADDR offset
, int len
)
2795 /* We make the process list snapshot when the object starts to be
2797 static const char *buf
;
2798 static long len_avail
= -1;
2799 static struct buffer buffer
;
2803 if (strcmp (annex
, "processes") != 0)
2806 if (!readbuf
|| writebuf
)
2811 if (len_avail
!= -1 && len_avail
!= 0)
2812 buffer_free (&buffer
);
2815 buffer_init (&buffer
);
2816 buffer_grow_str (&buffer
, "<osdata type=\"processes\">");
2818 dirp
= opendir ("/proc");
2822 while ((dp
= readdir (dirp
)) != NULL
)
2824 struct stat statbuf
;
2825 char procentry
[sizeof ("/proc/4294967295")];
2827 if (!isdigit (dp
->d_name
[0])
2828 || strlen (dp
->d_name
) > sizeof ("4294967295") - 1)
2831 sprintf (procentry
, "/proc/%s", dp
->d_name
);
2832 if (stat (procentry
, &statbuf
) == 0
2833 && S_ISDIR (statbuf
.st_mode
))
2837 char cmd
[MAXPATHLEN
+ 1];
2838 struct passwd
*entry
;
2840 sprintf (pathname
, "/proc/%s/cmdline", dp
->d_name
);
2841 entry
= getpwuid (statbuf
.st_uid
);
2843 if ((f
= fopen (pathname
, "r")) != NULL
)
2845 size_t len
= fread (cmd
, 1, sizeof (cmd
) - 1, f
);
2849 for (i
= 0; i
< len
; i
++)
2857 "<column name=\"pid\">%s</column>"
2858 "<column name=\"user\">%s</column>"
2859 "<column name=\"command\">%s</column>"
2862 entry
? entry
->pw_name
: "?",
2872 buffer_grow_str0 (&buffer
, "</osdata>\n");
2873 buf
= buffer_finish (&buffer
);
2874 len_avail
= strlen (buf
);
2877 if (offset
>= len_avail
)
2879 /* Done. Get rid of the data. */
2880 buffer_free (&buffer
);
2886 if (len
> len_avail
- offset
)
2887 len
= len_avail
- offset
;
2888 memcpy (readbuf
, buf
+ offset
, len
);
2893 /* Convert a native/host siginfo object, into/from the siginfo in the
2894 layout of the inferiors' architecture. */
2897 siginfo_fixup (struct siginfo
*siginfo
, void *inf_siginfo
, int direction
)
2901 if (the_low_target
.siginfo_fixup
!= NULL
)
2902 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
2904 /* If there was no callback, or the callback didn't do anything,
2905 then just do a straight memcpy. */
2909 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
2911 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
2916 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
2917 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
2920 struct siginfo siginfo
;
2921 char inf_siginfo
[sizeof (struct siginfo
)];
2923 if (current_inferior
== NULL
)
2926 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2929 fprintf (stderr
, "%s siginfo for lwp %d.\n",
2930 readbuf
!= NULL
? "Reading" : "Writing",
2933 if (offset
> sizeof (siginfo
))
2936 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
2939 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
2940 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
2941 inferior with a 64-bit GDBSERVER should look the same as debugging it
2942 with a 32-bit GDBSERVER, we need to convert it. */
2943 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
2945 if (offset
+ len
> sizeof (siginfo
))
2946 len
= sizeof (siginfo
) - offset
;
2948 if (readbuf
!= NULL
)
2949 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
2952 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
2954 /* Convert back to ptrace layout before flushing it out. */
2955 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
2957 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
2964 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
2965 so we notice when children change state; as the handler for the
2966 sigsuspend in my_waitpid. */
2969 sigchld_handler (int signo
)
2971 int old_errno
= errno
;
2974 /* fprintf is not async-signal-safe, so call write directly. */
2975 write (2, "sigchld_handler\n", sizeof ("sigchld_handler\n") - 1);
2977 if (target_is_async_p ())
2978 async_file_mark (); /* trigger a linux_wait */
2984 linux_supports_non_stop (void)
2990 linux_async (int enable
)
2992 int previous
= (linux_event_pipe
[0] != -1);
2994 if (previous
!= enable
)
2997 sigemptyset (&mask
);
2998 sigaddset (&mask
, SIGCHLD
);
3000 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
3004 if (pipe (linux_event_pipe
) == -1)
3005 fatal ("creating event pipe failed.");
3007 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
3008 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
3010 /* Register the event loop handler. */
3011 add_file_handler (linux_event_pipe
[0],
3012 handle_target_event
, NULL
);
3014 /* Always trigger a linux_wait. */
3019 delete_file_handler (linux_event_pipe
[0]);
3021 close (linux_event_pipe
[0]);
3022 close (linux_event_pipe
[1]);
3023 linux_event_pipe
[0] = -1;
3024 linux_event_pipe
[1] = -1;
3027 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
3034 linux_start_non_stop (int nonstop
)
3036 /* Register or unregister from event-loop accordingly. */
3037 linux_async (nonstop
);
3042 linux_supports_multi_process (void)
3048 /* Enumerate spufs IDs for process PID. */
3050 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
3056 struct dirent
*entry
;
3058 sprintf (path
, "/proc/%ld/fd", pid
);
3059 dir
= opendir (path
);
3064 while ((entry
= readdir (dir
)) != NULL
)
3070 fd
= atoi (entry
->d_name
);
3074 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
3075 if (stat (path
, &st
) != 0)
3077 if (!S_ISDIR (st
.st_mode
))
3080 if (statfs (path
, &stfs
) != 0)
3082 if (stfs
.f_type
!= SPUFS_MAGIC
)
3085 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
3087 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
3097 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
3098 object type, using the /proc file system. */
3100 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
3101 unsigned const char *writebuf
,
3102 CORE_ADDR offset
, int len
)
3104 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
3109 if (!writebuf
&& !readbuf
)
3117 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
3120 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
3121 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
3126 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
3133 ret
= write (fd
, writebuf
, (size_t) len
);
3135 ret
= read (fd
, readbuf
, (size_t) len
);
3141 static struct target_ops linux_target_ops
= {
3142 linux_create_inferior
,
3150 linux_fetch_registers
,
3151 linux_store_registers
,
3154 linux_look_up_symbols
,
3155 linux_request_interrupt
,
3159 linux_stopped_by_watchpoint
,
3160 linux_stopped_data_address
,
3161 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
3166 #ifdef USE_THREAD_DB
3167 thread_db_get_tls_address
,
3172 hostio_last_error_from_errno
,
3175 linux_supports_non_stop
,
3177 linux_start_non_stop
,
3178 linux_supports_multi_process
,
3179 #ifdef USE_THREAD_DB
3180 thread_db_handle_monitor_command
3187 linux_init_signals ()
3189 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
3190 to find what the cancel signal actually is. */
3191 signal (__SIGRTMIN
+1, SIG_IGN
);
3195 initialize_low (void)
3197 struct sigaction sigchld_action
;
3198 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
3199 set_target_ops (&linux_target_ops
);
3200 set_breakpoint_data (the_low_target
.breakpoint
,
3201 the_low_target
.breakpoint_len
);
3202 linux_init_signals ();
3203 linux_test_for_tracefork ();
3204 #ifdef HAVE_LINUX_REGSETS
3205 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
3207 disabled_regsets
= xmalloc (num_regsets
);
3210 sigchld_action
.sa_handler
= sigchld_handler
;
3211 sigemptyset (&sigchld_action
.sa_mask
);
3212 sigchld_action
.sa_flags
= SA_RESTART
;
3213 sigaction (SIGCHLD
, &sigchld_action
, NULL
);