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, 2010 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"
25 #include <sys/param.h>
26 #include <sys/ptrace.h>
28 #include <sys/ioctl.h>
34 #include <sys/syscall.h>
38 #include <sys/types.h>
43 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
44 then ELFMAG0 will have been defined. If it didn't get included by
45 gdb_proc_service.h then including it will likely introduce a duplicate
46 definition of elf_fpregset_t. */
51 #define SPUFS_MAGIC 0x23c9b64e
54 #ifndef PTRACE_GETSIGINFO
55 # define PTRACE_GETSIGINFO 0x4202
56 # define PTRACE_SETSIGINFO 0x4203
63 /* If the system headers did not provide the constants, hard-code the normal
65 #ifndef PTRACE_EVENT_FORK
67 #define PTRACE_SETOPTIONS 0x4200
68 #define PTRACE_GETEVENTMSG 0x4201
70 /* options set using PTRACE_SETOPTIONS */
71 #define PTRACE_O_TRACESYSGOOD 0x00000001
72 #define PTRACE_O_TRACEFORK 0x00000002
73 #define PTRACE_O_TRACEVFORK 0x00000004
74 #define PTRACE_O_TRACECLONE 0x00000008
75 #define PTRACE_O_TRACEEXEC 0x00000010
76 #define PTRACE_O_TRACEVFORKDONE 0x00000020
77 #define PTRACE_O_TRACEEXIT 0x00000040
79 /* Wait extended result codes for the above trace options. */
80 #define PTRACE_EVENT_FORK 1
81 #define PTRACE_EVENT_VFORK 2
82 #define PTRACE_EVENT_CLONE 3
83 #define PTRACE_EVENT_EXEC 4
84 #define PTRACE_EVENT_VFORK_DONE 5
85 #define PTRACE_EVENT_EXIT 6
87 #endif /* PTRACE_EVENT_FORK */
89 /* We can't always assume that this flag is available, but all systems
90 with the ptrace event handlers also have __WALL, so it's safe to use
93 #define __WALL 0x40000000 /* Wait for any child. */
97 #if !(defined(__UCLIBC_HAS_MMU__) || defined(__ARCH_HAS_MMU__))
102 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
103 representation of the thread ID.
105 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
106 the same as the LWP ID.
108 ``all_processes'' is keyed by the "overall process ID", which
109 GNU/Linux calls tgid, "thread group ID". */
111 struct inferior_list all_lwps
;
113 /* A list of all unknown processes which receive stop signals. Some other
114 process will presumably claim each of these as forked children
117 struct inferior_list stopped_pids
;
119 /* FIXME this is a bit of a hack, and could be removed. */
120 int stopping_threads
;
122 /* FIXME make into a target method? */
123 int using_threads
= 1;
125 /* This flag is true iff we've just created or attached to our first
126 inferior but it has not stopped yet. As soon as it does, we need
127 to call the low target's arch_setup callback. Doing this only on
128 the first inferior avoids reinializing the architecture on every
129 inferior, and avoids messing with the register caches of the
130 already running inferiors. NOTE: this assumes all inferiors under
131 control of gdbserver have the same architecture. */
132 static int new_inferior
;
134 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
135 int step
, int signal
, siginfo_t
*info
);
136 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
137 static void stop_all_lwps (void);
138 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
139 static int check_removed_breakpoint (struct lwp_info
*event_child
);
140 static void *add_lwp (ptid_t ptid
);
141 static int linux_stopped_by_watchpoint (void);
142 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
144 struct pending_signals
148 struct pending_signals
*prev
;
151 #define PTRACE_ARG3_TYPE long
152 #define PTRACE_XFER_TYPE long
154 #ifdef HAVE_LINUX_REGSETS
155 static char *disabled_regsets
;
156 static int num_regsets
;
159 /* The read/write ends of the pipe registered as waitable file in the
161 static int linux_event_pipe
[2] = { -1, -1 };
163 /* True if we're currently in async mode. */
164 #define target_is_async_p() (linux_event_pipe[0] != -1)
166 static void send_sigstop (struct inferior_list_entry
*entry
);
167 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
169 /* Accepts an integer PID; Returns a string representing a file that
170 can be opened to get info for the child process.
171 Space for the result is malloc'd, caller must free. */
174 linux_child_pid_to_exec_file (int pid
)
178 name1
= xmalloc (MAXPATHLEN
);
179 name2
= xmalloc (MAXPATHLEN
);
180 memset (name2
, 0, MAXPATHLEN
);
182 sprintf (name1
, "/proc/%d/exe", pid
);
183 if (readlink (name1
, name2
, MAXPATHLEN
) > 0)
195 /* Return non-zero if HEADER is a 64-bit ELF file. */
198 elf_64_header_p (const Elf64_Ehdr
*header
)
200 return (header
->e_ident
[EI_MAG0
] == ELFMAG0
201 && header
->e_ident
[EI_MAG1
] == ELFMAG1
202 && header
->e_ident
[EI_MAG2
] == ELFMAG2
203 && header
->e_ident
[EI_MAG3
] == ELFMAG3
204 && header
->e_ident
[EI_CLASS
] == ELFCLASS64
);
207 /* Return non-zero if FILE is a 64-bit ELF file,
208 zero if the file is not a 64-bit ELF file,
209 and -1 if the file is not accessible or doesn't exist. */
212 elf_64_file_p (const char *file
)
217 fd
= open (file
, O_RDONLY
);
221 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
228 return elf_64_header_p (&header
);
232 delete_lwp (struct lwp_info
*lwp
)
234 remove_thread (get_lwp_thread (lwp
));
235 remove_inferior (&all_lwps
, &lwp
->head
);
236 free (lwp
->arch_private
);
240 /* Add a process to the common process list, and set its private
243 static struct process_info
*
244 linux_add_process (int pid
, int attached
)
246 struct process_info
*proc
;
248 /* Is this the first process? If so, then set the arch. */
249 if (all_processes
.head
== NULL
)
252 proc
= add_process (pid
, attached
);
253 proc
->private = xcalloc (1, sizeof (*proc
->private));
255 if (the_low_target
.new_process
!= NULL
)
256 proc
->private->arch_private
= the_low_target
.new_process ();
261 /* Remove a process from the common process list,
262 also freeing all private data. */
265 linux_remove_process (struct process_info
*process
)
267 struct process_info_private
*priv
= process
->private;
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 thread_db_free (process
, 0);
743 linux_remove_process (process
);
748 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
750 struct thread_info
*thread
= (struct thread_info
*) entry
;
751 struct lwp_info
*lwp
= get_thread_lwp (thread
);
752 int pid
= * (int *) args
;
754 if (ptid_get_pid (entry
->id
) != pid
)
757 /* If we're detaching from a running inferior, make sure it is
758 stopped first, as PTRACE_DETACH will not work otherwise. */
761 int lwpid
= lwpid_of (lwp
);
763 stopping_threads
= 1;
764 send_sigstop (&lwp
->head
);
766 /* If this detects a new thread through a clone event, the new
767 thread is appended to the end of the lwp list, so we'll
768 eventually detach from it. */
769 wait_for_sigstop (&lwp
->head
);
770 stopping_threads
= 0;
772 /* If LWP exits while we're trying to stop it, there's nothing
774 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
779 /* Make sure the process isn't stopped at a breakpoint that's
781 check_removed_breakpoint (lwp
);
783 /* If this process is stopped but is expecting a SIGSTOP, then make
784 sure we take care of that now. This isn't absolutely guaranteed
785 to collect the SIGSTOP, but is fairly likely to. */
786 if (lwp
->stop_expected
)
789 /* Clear stop_expected, so that the SIGSTOP will be reported. */
790 lwp
->stop_expected
= 0;
792 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
793 linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
796 /* Flush any pending changes to the process's registers. */
797 regcache_invalidate_one ((struct inferior_list_entry
*)
798 get_lwp_thread (lwp
));
800 /* Finally, let it resume. */
801 ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0, 0);
808 any_thread_of (struct inferior_list_entry
*entry
, void *args
)
812 if (ptid_get_pid (entry
->id
) == *pid_p
)
819 linux_detach (int pid
)
821 struct process_info
*process
;
823 process
= find_process_pid (pid
);
828 thread_db_free (process
, 1);
832 (struct thread_info
*) find_inferior (&all_threads
, any_thread_of
, &pid
);
834 delete_all_breakpoints ();
835 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
836 linux_remove_process (process
);
844 struct process_info
*process
;
846 process
= find_process_pid (pid
);
851 ret
= my_waitpid (pid
, &status
, 0);
852 if (WIFEXITED (status
) || WIFSIGNALED (status
))
854 } while (ret
!= -1 || errno
!= ECHILD
);
857 /* Return nonzero if the given thread is still alive. */
859 linux_thread_alive (ptid_t ptid
)
861 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
863 /* We assume we always know if a thread exits. If a whole process
864 exited but we still haven't been able to report it to GDB, we'll
865 hold on to the last lwp of the dead process. */
872 /* Return nonzero if this process stopped at a breakpoint which
873 no longer appears to be inserted. Also adjust the PC
874 appropriately to resume where the breakpoint used to be. */
876 check_removed_breakpoint (struct lwp_info
*event_child
)
879 struct thread_info
*saved_inferior
;
881 if (event_child
->pending_is_breakpoint
== 0)
885 fprintf (stderr
, "Checking for breakpoint in lwp %ld.\n",
886 lwpid_of (event_child
));
888 saved_inferior
= current_inferior
;
889 current_inferior
= get_lwp_thread (event_child
);
891 stop_pc
= get_stop_pc ();
893 /* If the PC has changed since we stopped, then we shouldn't do
894 anything. This happens if, for instance, GDB handled the
895 decr_pc_after_break subtraction itself. */
896 if (stop_pc
!= event_child
->pending_stop_pc
)
899 fprintf (stderr
, "Ignoring, PC was changed. Old PC was 0x%08llx\n",
900 event_child
->pending_stop_pc
);
902 event_child
->pending_is_breakpoint
= 0;
903 current_inferior
= saved_inferior
;
907 /* If the breakpoint is still there, we will report hitting it. */
908 if ((*the_low_target
.breakpoint_at
) (stop_pc
))
911 fprintf (stderr
, "Ignoring, breakpoint is still present.\n");
912 current_inferior
= saved_inferior
;
917 fprintf (stderr
, "Removed breakpoint.\n");
919 /* For decr_pc_after_break targets, here is where we perform the
920 decrement. We go immediately from this function to resuming,
921 and can not safely call get_stop_pc () again. */
922 if (the_low_target
.set_pc
!= NULL
)
925 fprintf (stderr
, "Set pc to 0x%lx\n", (long) stop_pc
);
926 (*the_low_target
.set_pc
) (stop_pc
);
929 /* We consumed the pending SIGTRAP. */
930 event_child
->pending_is_breakpoint
= 0;
931 event_child
->status_pending_p
= 0;
932 event_child
->status_pending
= 0;
934 current_inferior
= saved_inferior
;
938 /* Return 1 if this lwp has an interesting status pending. This
939 function may silently resume an inferior lwp. */
941 status_pending_p (struct inferior_list_entry
*entry
, void *arg
)
943 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
944 ptid_t ptid
= * (ptid_t
*) arg
;
946 /* Check if we're only interested in events from a specific process
948 if (!ptid_equal (minus_one_ptid
, ptid
)
949 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
952 if (lwp
->status_pending_p
&& !lwp
->suspended
)
953 if (check_removed_breakpoint (lwp
))
955 /* This thread was stopped at a breakpoint, and the breakpoint
956 is now gone. We were told to continue (or step...) all threads,
957 so GDB isn't trying to single-step past this breakpoint.
958 So instead of reporting the old SIGTRAP, pretend we got to
959 the breakpoint just after it was removed instead of just
960 before; resume the process. */
961 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
965 return (lwp
->status_pending_p
&& !lwp
->suspended
);
969 same_lwp (struct inferior_list_entry
*entry
, void *data
)
971 ptid_t ptid
= *(ptid_t
*) data
;
974 if (ptid_get_lwp (ptid
) != 0)
975 lwp
= ptid_get_lwp (ptid
);
977 lwp
= ptid_get_pid (ptid
);
979 if (ptid_get_lwp (entry
->id
) == lwp
)
986 find_lwp_pid (ptid_t ptid
)
988 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
991 static struct lwp_info
*
992 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
995 int to_wait_for
= -1;
996 struct lwp_info
*child
= NULL
;
999 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1001 if (ptid_equal (ptid
, minus_one_ptid
))
1002 to_wait_for
= -1; /* any child */
1004 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1010 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1011 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1014 perror_with_name ("waitpid");
1017 && (!WIFSTOPPED (*wstatp
)
1018 || (WSTOPSIG (*wstatp
) != 32
1019 && WSTOPSIG (*wstatp
) != 33)))
1020 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1022 child
= find_lwp_pid (pid_to_ptid (ret
));
1024 /* If we didn't find a process, one of two things presumably happened:
1025 - A process we started and then detached from has exited. Ignore it.
1026 - A process we are controlling has forked and the new child's stop
1027 was reported to us by the kernel. Save its PID. */
1028 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1030 add_pid_to_list (&stopped_pids
, ret
);
1033 else if (child
== NULL
)
1037 child
->pending_is_breakpoint
= 0;
1039 child
->last_status
= *wstatp
;
1041 /* Architecture-specific setup after inferior is running.
1042 This needs to happen after we have attached to the inferior
1043 and it is stopped for the first time, but before we access
1044 any inferior registers. */
1047 the_low_target
.arch_setup ();
1048 #ifdef HAVE_LINUX_REGSETS
1049 memset (disabled_regsets
, 0, num_regsets
);
1055 && WIFSTOPPED (*wstatp
)
1056 && the_low_target
.get_pc
!= NULL
)
1058 struct thread_info
*saved_inferior
= current_inferior
;
1061 current_inferior
= (struct thread_info
*)
1062 find_inferior_id (&all_threads
, child
->head
.id
);
1063 pc
= (*the_low_target
.get_pc
) ();
1064 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1065 current_inferior
= saved_inferior
;
1071 /* Wait for an event from child PID. If PID is -1, wait for any
1072 child. Store the stop status through the status pointer WSTAT.
1073 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1074 event was found and OPTIONS contains WNOHANG. Return the PID of
1075 the stopped child otherwise. */
1078 linux_wait_for_event_1 (ptid_t ptid
, int *wstat
, int options
)
1081 struct lwp_info
*event_child
= NULL
;
1083 struct lwp_info
*requested_child
= NULL
;
1085 /* Check for a lwp with a pending status. */
1086 /* It is possible that the user changed the pending task's registers since
1087 it stopped. We correctly handle the change of PC if we hit a breakpoint
1088 (in check_removed_breakpoint); signals should be reported anyway. */
1090 if (ptid_equal (ptid
, minus_one_ptid
)
1091 || ptid_equal (pid_to_ptid (ptid_get_pid (ptid
)), ptid
))
1093 event_child
= (struct lwp_info
*)
1094 find_inferior (&all_lwps
, status_pending_p
, &ptid
);
1095 if (debug_threads
&& event_child
)
1096 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1100 requested_child
= find_lwp_pid (ptid
);
1101 if (requested_child
->status_pending_p
1102 && !check_removed_breakpoint (requested_child
))
1103 event_child
= requested_child
;
1106 if (event_child
!= NULL
)
1109 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1110 lwpid_of (event_child
), event_child
->status_pending
);
1111 *wstat
= event_child
->status_pending
;
1112 event_child
->status_pending_p
= 0;
1113 event_child
->status_pending
= 0;
1114 current_inferior
= get_lwp_thread (event_child
);
1115 return lwpid_of (event_child
);
1118 /* We only enter this loop if no process has a pending wait status. Thus
1119 any action taken in response to a wait status inside this loop is
1120 responding as soon as we detect the status, not after any pending
1124 event_child
= linux_wait_for_lwp (ptid
, wstat
, options
);
1126 if ((options
& WNOHANG
) && event_child
== NULL
)
1129 if (event_child
== NULL
)
1130 error ("event from unknown child");
1132 current_inferior
= get_lwp_thread (event_child
);
1134 /* Check for thread exit. */
1135 if (! WIFSTOPPED (*wstat
))
1138 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1140 /* If the last thread is exiting, just return. */
1141 if (last_thread_of_process_p (current_inferior
))
1144 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1145 lwpid_of (event_child
));
1146 return lwpid_of (event_child
);
1149 delete_lwp (event_child
);
1153 current_inferior
= (struct thread_info
*) all_threads
.head
;
1155 fprintf (stderr
, "Current inferior is now %ld\n",
1156 lwpid_of (get_thread_lwp (current_inferior
)));
1160 current_inferior
= NULL
;
1162 fprintf (stderr
, "Current inferior is now <NULL>\n");
1165 /* If we were waiting for this particular child to do something...
1166 well, it did something. */
1167 if (requested_child
!= NULL
)
1168 return lwpid_of (event_child
);
1170 /* Wait for a more interesting event. */
1174 if (event_child
->must_set_ptrace_flags
)
1176 ptrace (PTRACE_SETOPTIONS
, lwpid_of (event_child
),
1177 0, PTRACE_O_TRACECLONE
);
1178 event_child
->must_set_ptrace_flags
= 0;
1181 if (WIFSTOPPED (*wstat
)
1182 && WSTOPSIG (*wstat
) == SIGSTOP
1183 && event_child
->stop_expected
)
1186 fprintf (stderr
, "Expected stop.\n");
1187 event_child
->stop_expected
= 0;
1188 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
1192 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1193 && *wstat
>> 16 != 0)
1195 handle_extended_wait (event_child
, *wstat
);
1199 /* If GDB is not interested in this signal, don't stop other
1200 threads, and don't report it to GDB. Just resume the
1201 inferior right away. We do this for threading-related
1202 signals as well as any that GDB specifically requested we
1203 ignore. But never ignore SIGSTOP if we sent it ourselves,
1204 and do not ignore signals when stepping - they may require
1205 special handling to skip the signal handler. */
1206 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
1208 if (WIFSTOPPED (*wstat
)
1209 && !event_child
->stepping
1211 #ifdef USE_THREAD_DB
1212 (current_process ()->private->thread_db
!= NULL
1213 && (WSTOPSIG (*wstat
) == __SIGRTMIN
1214 || WSTOPSIG (*wstat
) == __SIGRTMIN
+ 1))
1217 (pass_signals
[target_signal_from_host (WSTOPSIG (*wstat
))]
1218 && (WSTOPSIG (*wstat
) != SIGSTOP
|| !stopping_threads
))))
1220 siginfo_t info
, *info_p
;
1223 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
1224 WSTOPSIG (*wstat
), lwpid_of (event_child
));
1226 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
1230 linux_resume_one_lwp (event_child
,
1231 event_child
->stepping
,
1232 WSTOPSIG (*wstat
), info_p
);
1236 /* If this event was not handled above, and is not a SIGTRAP, report
1238 if (!WIFSTOPPED (*wstat
) || WSTOPSIG (*wstat
) != SIGTRAP
)
1239 return lwpid_of (event_child
);
1241 /* If this target does not support breakpoints, we simply report the
1242 SIGTRAP; it's of no concern to us. */
1243 if (the_low_target
.get_pc
== NULL
)
1244 return lwpid_of (event_child
);
1246 stop_pc
= get_stop_pc ();
1248 /* bp_reinsert will only be set if we were single-stepping.
1249 Notice that we will resume the process after hitting
1250 a gdbserver breakpoint; single-stepping to/over one
1251 is not supported (yet). */
1252 if (event_child
->bp_reinsert
!= 0)
1255 fprintf (stderr
, "Reinserted breakpoint.\n");
1256 reinsert_breakpoint (event_child
->bp_reinsert
);
1257 event_child
->bp_reinsert
= 0;
1259 /* Clear the single-stepping flag and SIGTRAP as we resume. */
1260 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1264 bp_status
= check_breakpoints (stop_pc
);
1269 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
1271 /* We hit one of our own breakpoints. We mark it as a pending
1272 breakpoint, so that check_removed_breakpoint () will do the PC
1273 adjustment for us at the appropriate time. */
1274 event_child
->pending_is_breakpoint
= 1;
1275 event_child
->pending_stop_pc
= stop_pc
;
1277 /* We may need to put the breakpoint back. We continue in the event
1278 loop instead of simply replacing the breakpoint right away,
1279 in order to not lose signals sent to the thread that hit the
1280 breakpoint. Unfortunately this increases the window where another
1281 thread could sneak past the removed breakpoint. For the current
1282 use of server-side breakpoints (thread creation) this is
1283 acceptable; but it needs to be considered before this breakpoint
1284 mechanism can be used in more general ways. For some breakpoints
1285 it may be necessary to stop all other threads, but that should
1286 be avoided where possible.
1288 If breakpoint_reinsert_addr is NULL, that means that we can
1289 use PTRACE_SINGLESTEP on this platform. Uninsert the breakpoint,
1290 mark it for reinsertion, and single-step.
1292 Otherwise, call the target function to figure out where we need
1293 our temporary breakpoint, create it, and continue executing this
1296 /* NOTE: we're lifting breakpoints in non-stop mode. This
1297 is currently only used for thread event breakpoints, so
1298 it isn't that bad as long as we have PTRACE_EVENT_CLONE
1301 /* No need to reinsert. */
1302 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1303 else if (the_low_target
.breakpoint_reinsert_addr
== NULL
)
1305 event_child
->bp_reinsert
= stop_pc
;
1306 uninsert_breakpoint (stop_pc
);
1307 linux_resume_one_lwp (event_child
, 1, 0, NULL
);
1311 reinsert_breakpoint_by_bp
1312 (stop_pc
, (*the_low_target
.breakpoint_reinsert_addr
) ());
1313 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1320 fprintf (stderr
, "Hit a non-gdbserver breakpoint.\n");
1322 /* If we were single-stepping, we definitely want to report the
1323 SIGTRAP. Although the single-step operation has completed,
1324 do not clear clear the stepping flag yet; we need to check it
1325 in wait_for_sigstop. */
1326 if (event_child
->stepping
)
1327 return lwpid_of (event_child
);
1329 /* A SIGTRAP that we can't explain. It may have been a breakpoint.
1330 Check if it is a breakpoint, and if so mark the process information
1331 accordingly. This will handle both the necessary fiddling with the
1332 PC on decr_pc_after_break targets and suppressing extra threads
1333 hitting a breakpoint if two hit it at once and then GDB removes it
1334 after the first is reported. Arguably it would be better to report
1335 multiple threads hitting breakpoints simultaneously, but the current
1336 remote protocol does not allow this. */
1337 if ((*the_low_target
.breakpoint_at
) (stop_pc
))
1339 event_child
->pending_is_breakpoint
= 1;
1340 event_child
->pending_stop_pc
= stop_pc
;
1343 return lwpid_of (event_child
);
1351 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1355 if (ptid_is_pid (ptid
))
1357 /* A request to wait for a specific tgid. This is not possible
1358 with waitpid, so instead, we wait for any child, and leave
1359 children we're not interested in right now with a pending
1360 status to report later. */
1361 wait_ptid
= minus_one_ptid
;
1370 event_pid
= linux_wait_for_event_1 (wait_ptid
, wstat
, options
);
1373 && ptid_is_pid (ptid
) && ptid_get_pid (ptid
) != event_pid
)
1375 struct lwp_info
*event_child
= find_lwp_pid (pid_to_ptid (event_pid
));
1377 if (! WIFSTOPPED (*wstat
))
1378 mark_lwp_dead (event_child
, *wstat
);
1381 event_child
->status_pending_p
= 1;
1382 event_child
->status_pending
= *wstat
;
1390 /* Wait for process, returns status. */
1393 linux_wait_1 (ptid_t ptid
,
1394 struct target_waitstatus
*ourstatus
, int target_options
)
1397 struct thread_info
*thread
= NULL
;
1398 struct lwp_info
*lwp
= NULL
;
1402 /* Translate generic target options into linux options. */
1404 if (target_options
& TARGET_WNOHANG
)
1408 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
1410 /* If we were only supposed to resume one thread, only wait for
1411 that thread - if it's still alive. If it died, however - which
1412 can happen if we're coming from the thread death case below -
1413 then we need to make sure we restart the other threads. We could
1414 pick a thread at random or restart all; restarting all is less
1417 && !ptid_equal (cont_thread
, null_ptid
)
1418 && !ptid_equal (cont_thread
, minus_one_ptid
))
1420 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
1423 /* No stepping, no signal - unless one is pending already, of course. */
1426 struct thread_resume resume_info
;
1427 resume_info
.thread
= minus_one_ptid
;
1428 resume_info
.kind
= resume_continue
;
1429 resume_info
.sig
= 0;
1430 linux_resume (&resume_info
, 1);
1436 pid
= linux_wait_for_event (ptid
, &w
, options
);
1437 if (pid
== 0) /* only if TARGET_WNOHANG */
1440 lwp
= get_thread_lwp (current_inferior
);
1442 /* If we are waiting for a particular child, and it exited,
1443 linux_wait_for_event will return its exit status. Similarly if
1444 the last child exited. If this is not the last child, however,
1445 do not report it as exited until there is a 'thread exited' response
1446 available in the remote protocol. Instead, just wait for another event.
1447 This should be safe, because if the thread crashed we will already
1448 have reported the termination signal to GDB; that should stop any
1449 in-progress stepping operations, etc.
1451 Report the exit status of the last thread to exit. This matches
1452 LinuxThreads' behavior. */
1454 if (last_thread_of_process_p (current_inferior
))
1456 if (WIFEXITED (w
) || WIFSIGNALED (w
))
1458 int pid
= pid_of (lwp
);
1459 struct process_info
*process
= find_process_pid (pid
);
1461 #ifdef USE_THREAD_DB
1462 thread_db_free (process
, 0);
1465 linux_remove_process (process
);
1467 current_inferior
= NULL
;
1471 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
1472 ourstatus
->value
.integer
= WEXITSTATUS (w
);
1475 fprintf (stderr
, "\nChild exited with retcode = %x \n", WEXITSTATUS (w
));
1479 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
1480 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
1483 fprintf (stderr
, "\nChild terminated with signal = %x \n", WTERMSIG (w
));
1487 return pid_to_ptid (pid
);
1492 if (!WIFSTOPPED (w
))
1496 /* In all-stop, stop all threads. Be careful to only do this if
1497 we're about to report an event to GDB. */
1501 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
1503 if (lwp
->suspended
&& WSTOPSIG (w
) == SIGSTOP
)
1505 /* A thread that has been requested to stop by GDB with vCont;t,
1506 and it stopped cleanly, so report as SIG0. The use of
1507 SIGSTOP is an implementation detail. */
1508 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
1510 else if (lwp
->suspended
&& WSTOPSIG (w
) != SIGSTOP
)
1512 /* A thread that has been requested to stop by GDB with vCont;t,
1513 but, it stopped for other reasons. Set stop_expected so the
1514 pending SIGSTOP is ignored and the LWP is resumed. */
1515 lwp
->stop_expected
= 1;
1516 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
1520 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
1524 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
1525 target_pid_to_str (lwp
->head
.id
),
1527 ourstatus
->value
.sig
);
1529 return lwp
->head
.id
;
1532 /* Get rid of any pending event in the pipe. */
1534 async_file_flush (void)
1540 ret
= read (linux_event_pipe
[0], &buf
, 1);
1541 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
1544 /* Put something in the pipe, so the event loop wakes up. */
1546 async_file_mark (void)
1550 async_file_flush ();
1553 ret
= write (linux_event_pipe
[1], "+", 1);
1554 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
1556 /* Ignore EAGAIN. If the pipe is full, the event loop will already
1557 be awakened anyway. */
1561 linux_wait (ptid_t ptid
,
1562 struct target_waitstatus
*ourstatus
, int target_options
)
1567 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
1569 /* Flush the async file first. */
1570 if (target_is_async_p ())
1571 async_file_flush ();
1573 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
1575 /* If at least one stop was reported, there may be more. A single
1576 SIGCHLD can signal more than one child stop. */
1577 if (target_is_async_p ()
1578 && (target_options
& TARGET_WNOHANG
) != 0
1579 && !ptid_equal (event_ptid
, null_ptid
))
1585 /* Send a signal to an LWP. */
1588 kill_lwp (unsigned long lwpid
, int signo
)
1590 /* Use tkill, if possible, in case we are using nptl threads. If tkill
1591 fails, then we are not using nptl threads and we should be using kill. */
1595 static int tkill_failed
;
1602 ret
= syscall (__NR_tkill
, lwpid
, signo
);
1603 if (errno
!= ENOSYS
)
1610 return kill (lwpid
, signo
);
1614 send_sigstop (struct inferior_list_entry
*entry
)
1616 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1622 pid
= lwpid_of (lwp
);
1624 /* If we already have a pending stop signal for this process, don't
1626 if (lwp
->stop_expected
)
1629 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
1631 /* We clear the stop_expected flag so that wait_for_sigstop
1632 will receive the SIGSTOP event (instead of silently resuming and
1633 waiting again). It'll be reset below. */
1634 lwp
->stop_expected
= 0;
1639 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
1641 kill_lwp (pid
, SIGSTOP
);
1645 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
1647 /* It's dead, really. */
1650 /* Store the exit status for later. */
1651 lwp
->status_pending_p
= 1;
1652 lwp
->status_pending
= wstat
;
1654 /* So that check_removed_breakpoint doesn't try to figure out if
1655 this is stopped at a breakpoint. */
1656 lwp
->pending_is_breakpoint
= 0;
1658 /* Prevent trying to stop it. */
1661 /* No further stops are expected from a dead lwp. */
1662 lwp
->stop_expected
= 0;
1666 wait_for_sigstop (struct inferior_list_entry
*entry
)
1668 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1669 struct thread_info
*saved_inferior
;
1677 saved_inferior
= current_inferior
;
1678 if (saved_inferior
!= NULL
)
1679 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
1681 saved_tid
= null_ptid
; /* avoid bogus unused warning */
1683 ptid
= lwp
->head
.id
;
1685 linux_wait_for_event (ptid
, &wstat
, __WALL
);
1687 /* If we stopped with a non-SIGSTOP signal, save it for later
1688 and record the pending SIGSTOP. If the process exited, just
1690 if (WIFSTOPPED (wstat
)
1691 && WSTOPSIG (wstat
) != SIGSTOP
)
1694 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
1695 lwpid_of (lwp
), wstat
);
1697 /* Do not leave a pending single-step finish to be reported to
1698 the client. The client will give us a new action for this
1699 thread, possibly a continue request --- otherwise, the client
1700 would consider this pending SIGTRAP reported later a spurious
1702 if (WSTOPSIG (wstat
) == SIGTRAP
1704 && !linux_stopped_by_watchpoint ())
1707 fprintf (stderr
, " single-step SIGTRAP ignored\n");
1711 lwp
->status_pending_p
= 1;
1712 lwp
->status_pending
= wstat
;
1714 lwp
->stop_expected
= 1;
1716 else if (!WIFSTOPPED (wstat
))
1719 fprintf (stderr
, "Process %ld exited while stopping LWPs\n",
1722 /* Leave this status pending for the next time we're able to
1723 report it. In the mean time, we'll report this lwp as dead
1724 to GDB, so GDB doesn't try to read registers and memory from
1726 mark_lwp_dead (lwp
, wstat
);
1729 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
1730 current_inferior
= saved_inferior
;
1734 fprintf (stderr
, "Previously current thread died.\n");
1738 /* We can't change the current inferior behind GDB's back,
1739 otherwise, a subsequent command may apply to the wrong
1741 current_inferior
= NULL
;
1745 /* Set a valid thread as current. */
1746 set_desired_inferior (0);
1752 stop_all_lwps (void)
1754 stopping_threads
= 1;
1755 for_each_inferior (&all_lwps
, send_sigstop
);
1756 for_each_inferior (&all_lwps
, wait_for_sigstop
);
1757 stopping_threads
= 0;
1760 /* Resume execution of the inferior process.
1761 If STEP is nonzero, single-step it.
1762 If SIGNAL is nonzero, give it that signal. */
1765 linux_resume_one_lwp (struct lwp_info
*lwp
,
1766 int step
, int signal
, siginfo_t
*info
)
1768 struct thread_info
*saved_inferior
;
1770 if (lwp
->stopped
== 0)
1773 /* If we have pending signals or status, and a new signal, enqueue the
1774 signal. Also enqueue the signal if we are waiting to reinsert a
1775 breakpoint; it will be picked up again below. */
1777 && (lwp
->status_pending_p
|| lwp
->pending_signals
!= NULL
1778 || lwp
->bp_reinsert
!= 0))
1780 struct pending_signals
*p_sig
;
1781 p_sig
= xmalloc (sizeof (*p_sig
));
1782 p_sig
->prev
= lwp
->pending_signals
;
1783 p_sig
->signal
= signal
;
1785 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1787 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
1788 lwp
->pending_signals
= p_sig
;
1791 if (lwp
->status_pending_p
&& !check_removed_breakpoint (lwp
))
1794 saved_inferior
= current_inferior
;
1795 current_inferior
= get_lwp_thread (lwp
);
1798 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
1799 lwpid_of (lwp
), step
? "step" : "continue", signal
,
1800 lwp
->stop_expected
? "expected" : "not expected");
1802 /* This bit needs some thinking about. If we get a signal that
1803 we must report while a single-step reinsert is still pending,
1804 we often end up resuming the thread. It might be better to
1805 (ew) allow a stack of pending events; then we could be sure that
1806 the reinsert happened right away and not lose any signals.
1808 Making this stack would also shrink the window in which breakpoints are
1809 uninserted (see comment in linux_wait_for_lwp) but not enough for
1810 complete correctness, so it won't solve that problem. It may be
1811 worthwhile just to solve this one, however. */
1812 if (lwp
->bp_reinsert
!= 0)
1815 fprintf (stderr
, " pending reinsert at %08lx", (long)lwp
->bp_reinsert
);
1817 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
1820 /* Postpone any pending signal. It was enqueued above. */
1824 check_removed_breakpoint (lwp
);
1826 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
1828 CORE_ADDR pc
= (*the_low_target
.get_pc
) ();
1829 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
1832 /* If we have pending signals, consume one unless we are trying to reinsert
1834 if (lwp
->pending_signals
!= NULL
&& lwp
->bp_reinsert
== 0)
1836 struct pending_signals
**p_sig
;
1838 p_sig
= &lwp
->pending_signals
;
1839 while ((*p_sig
)->prev
!= NULL
)
1840 p_sig
= &(*p_sig
)->prev
;
1842 signal
= (*p_sig
)->signal
;
1843 if ((*p_sig
)->info
.si_signo
!= 0)
1844 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
1850 if (the_low_target
.prepare_to_resume
!= NULL
)
1851 the_low_target
.prepare_to_resume (lwp
);
1853 regcache_invalidate_one ((struct inferior_list_entry
*)
1854 get_lwp_thread (lwp
));
1857 lwp
->stepping
= step
;
1858 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0, signal
);
1860 current_inferior
= saved_inferior
;
1863 /* ESRCH from ptrace either means that the thread was already
1864 running (an error) or that it is gone (a race condition). If
1865 it's gone, we will get a notification the next time we wait,
1866 so we can ignore the error. We could differentiate these
1867 two, but it's tricky without waiting; the thread still exists
1868 as a zombie, so sending it signal 0 would succeed. So just
1873 perror_with_name ("ptrace");
1877 struct thread_resume_array
1879 struct thread_resume
*resume
;
1883 /* This function is called once per thread. We look up the thread
1884 in RESUME_PTR, and mark the thread with a pointer to the appropriate
1887 This algorithm is O(threads * resume elements), but resume elements
1888 is small (and will remain small at least until GDB supports thread
1891 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
1893 struct lwp_info
*lwp
;
1894 struct thread_info
*thread
;
1896 struct thread_resume_array
*r
;
1898 thread
= (struct thread_info
*) entry
;
1899 lwp
= get_thread_lwp (thread
);
1902 for (ndx
= 0; ndx
< r
->n
; ndx
++)
1904 ptid_t ptid
= r
->resume
[ndx
].thread
;
1905 if (ptid_equal (ptid
, minus_one_ptid
)
1906 || ptid_equal (ptid
, entry
->id
)
1907 || (ptid_is_pid (ptid
)
1908 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
1909 || (ptid_get_lwp (ptid
) == -1
1910 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
1912 lwp
->resume
= &r
->resume
[ndx
];
1917 /* No resume action for this thread. */
1924 /* Set *FLAG_P if this lwp has an interesting status pending. */
1926 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
1928 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1930 /* LWPs which will not be resumed are not interesting, because
1931 we might not wait for them next time through linux_wait. */
1932 if (lwp
->resume
== NULL
)
1935 /* If this thread has a removed breakpoint, we won't have any
1936 events to report later, so check now. check_removed_breakpoint
1937 may clear status_pending_p. We avoid calling check_removed_breakpoint
1938 for any thread that we are not otherwise going to resume - this
1939 lets us preserve stopped status when two threads hit a breakpoint.
1940 GDB removes the breakpoint to single-step a particular thread
1941 past it, then re-inserts it and resumes all threads. We want
1942 to report the second thread without resuming it in the interim. */
1943 if (lwp
->status_pending_p
)
1944 check_removed_breakpoint (lwp
);
1946 if (lwp
->status_pending_p
)
1947 * (int *) flag_p
= 1;
1952 /* This function is called once per thread. We check the thread's resume
1953 request, which will tell us whether to resume, step, or leave the thread
1954 stopped; and what signal, if any, it should be sent.
1956 For threads which we aren't explicitly told otherwise, we preserve
1957 the stepping flag; this is used for stepping over gdbserver-placed
1960 If pending_flags was set in any thread, we queue any needed
1961 signals, since we won't actually resume. We already have a pending
1962 event to report, so we don't need to preserve any step requests;
1963 they should be re-issued if necessary. */
1966 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
1968 struct lwp_info
*lwp
;
1969 struct thread_info
*thread
;
1971 int pending_flag
= * (int *) arg
;
1973 thread
= (struct thread_info
*) entry
;
1974 lwp
= get_thread_lwp (thread
);
1976 if (lwp
->resume
== NULL
)
1979 if (lwp
->resume
->kind
== resume_stop
)
1982 fprintf (stderr
, "suspending LWP %ld\n", lwpid_of (lwp
));
1987 fprintf (stderr
, "running -> suspending LWP %ld\n", lwpid_of (lwp
));
1990 send_sigstop (&lwp
->head
);
1997 fprintf (stderr
, "already stopped/suspended LWP %ld\n",
2000 fprintf (stderr
, "already stopped/not suspended LWP %ld\n",
2004 /* Make sure we leave the LWP suspended, so we don't try to
2005 resume it without GDB telling us to. FIXME: The LWP may
2006 have been stopped in an internal event that was not meant
2007 to be notified back to GDB (e.g., gdbserver breakpoint),
2008 so we should be reporting a stop event in that case
2013 /* For stop requests, we're done. */
2020 /* If this thread which is about to be resumed has a pending status,
2021 then don't resume any threads - we can just report the pending
2022 status. Make sure to queue any signals that would otherwise be
2023 sent. In all-stop mode, we do this decision based on if *any*
2024 thread has a pending status. */
2026 resume_status_pending_p (&lwp
->head
, &pending_flag
);
2031 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
2033 if (ptid_equal (lwp
->resume
->thread
, minus_one_ptid
)
2035 && lwp
->pending_is_breakpoint
)
2038 step
= (lwp
->resume
->kind
== resume_step
);
2040 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
2045 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
2047 /* If we have a new signal, enqueue the signal. */
2048 if (lwp
->resume
->sig
!= 0)
2050 struct pending_signals
*p_sig
;
2051 p_sig
= xmalloc (sizeof (*p_sig
));
2052 p_sig
->prev
= lwp
->pending_signals
;
2053 p_sig
->signal
= lwp
->resume
->sig
;
2054 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
2056 /* If this is the same signal we were previously stopped by,
2057 make sure to queue its siginfo. We can ignore the return
2058 value of ptrace; if it fails, we'll skip
2059 PTRACE_SETSIGINFO. */
2060 if (WIFSTOPPED (lwp
->last_status
)
2061 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
2062 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
2064 lwp
->pending_signals
= p_sig
;
2073 linux_resume (struct thread_resume
*resume_info
, size_t n
)
2076 struct thread_resume_array array
= { resume_info
, n
};
2078 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
2080 /* If there is a thread which would otherwise be resumed, which
2081 has a pending status, then don't resume any threads - we can just
2082 report the pending status. Make sure to queue any signals
2083 that would otherwise be sent. In non-stop mode, we'll apply this
2084 logic to each thread individually. */
2087 find_inferior (&all_lwps
, resume_status_pending_p
, &pending_flag
);
2092 fprintf (stderr
, "Not resuming, pending status\n");
2094 fprintf (stderr
, "Resuming, no pending status\n");
2097 find_inferior (&all_threads
, linux_resume_one_thread
, &pending_flag
);
2100 #ifdef HAVE_LINUX_USRREGS
2103 register_addr (int regnum
)
2107 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
2108 error ("Invalid register number %d.", regnum
);
2110 addr
= the_low_target
.regmap
[regnum
];
2115 /* Fetch one register. */
2117 fetch_register (int regno
)
2124 if (regno
>= the_low_target
.num_regs
)
2126 if ((*the_low_target
.cannot_fetch_register
) (regno
))
2129 regaddr
= register_addr (regno
);
2133 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2134 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2135 & - sizeof (PTRACE_XFER_TYPE
));
2136 buf
= alloca (size
);
2137 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
2140 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
2141 ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_ARG3_TYPE
) regaddr
, 0);
2142 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
2145 /* Warning, not error, in case we are attached; sometimes the
2146 kernel doesn't let us at the registers. */
2147 char *err
= strerror (errno
);
2148 char *msg
= alloca (strlen (err
) + 128);
2149 sprintf (msg
, "reading register %d: %s", regno
, err
);
2155 if (the_low_target
.supply_ptrace_register
)
2156 the_low_target
.supply_ptrace_register (regno
, buf
);
2158 supply_register (regno
, buf
);
2163 /* Fetch all registers, or just one, from the child process. */
2165 usr_fetch_inferior_registers (int regno
)
2168 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
2169 fetch_register (regno
);
2171 fetch_register (regno
);
2174 /* Store our register values back into the inferior.
2175 If REGNO is -1, do this for all registers.
2176 Otherwise, REGNO specifies which register (so we can save time). */
2178 usr_store_inferior_registers (int regno
)
2187 if (regno
>= the_low_target
.num_regs
)
2190 if ((*the_low_target
.cannot_store_register
) (regno
) == 1)
2193 regaddr
= register_addr (regno
);
2197 size
= (register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2198 & - sizeof (PTRACE_XFER_TYPE
);
2199 buf
= alloca (size
);
2200 memset (buf
, 0, size
);
2202 if (the_low_target
.collect_ptrace_register
)
2203 the_low_target
.collect_ptrace_register (regno
, buf
);
2205 collect_register (regno
, buf
);
2207 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2208 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
2211 ptrace (PTRACE_POKEUSER
, pid
, (PTRACE_ARG3_TYPE
) regaddr
,
2212 *(PTRACE_XFER_TYPE
*) (buf
+ i
));
2215 /* At this point, ESRCH should mean the process is
2216 already gone, in which case we simply ignore attempts
2217 to change its registers. See also the related
2218 comment in linux_resume_one_lwp. */
2222 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
2224 char *err
= strerror (errno
);
2225 char *msg
= alloca (strlen (err
) + 128);
2226 sprintf (msg
, "writing register %d: %s",
2232 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
2236 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
2237 usr_store_inferior_registers (regno
);
2239 #endif /* HAVE_LINUX_USRREGS */
2243 #ifdef HAVE_LINUX_REGSETS
2246 regsets_fetch_inferior_registers ()
2248 struct regset_info
*regset
;
2249 int saw_general_regs
= 0;
2252 regset
= target_regsets
;
2254 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2255 while (regset
->size
>= 0)
2260 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
2266 buf
= xmalloc (regset
->size
);
2268 res
= ptrace (regset
->get_request
, pid
, 0, buf
);
2270 res
= ptrace (regset
->get_request
, pid
, buf
, 0);
2276 /* If we get EIO on a regset, do not try it again for
2278 disabled_regsets
[regset
- target_regsets
] = 1;
2285 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
2290 else if (regset
->type
== GENERAL_REGS
)
2291 saw_general_regs
= 1;
2292 regset
->store_function (buf
);
2296 if (saw_general_regs
)
2303 regsets_store_inferior_registers ()
2305 struct regset_info
*regset
;
2306 int saw_general_regs
= 0;
2309 regset
= target_regsets
;
2311 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2312 while (regset
->size
>= 0)
2317 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
2323 buf
= xmalloc (regset
->size
);
2325 /* First fill the buffer with the current register set contents,
2326 in case there are any items in the kernel's regset that are
2327 not in gdbserver's regcache. */
2329 res
= ptrace (regset
->get_request
, pid
, 0, buf
);
2331 res
= ptrace (regset
->get_request
, pid
, buf
, 0);
2336 /* Then overlay our cached registers on that. */
2337 regset
->fill_function (buf
);
2339 /* Only now do we write the register set. */
2341 res
= ptrace (regset
->set_request
, pid
, 0, buf
);
2343 res
= ptrace (regset
->set_request
, pid
, buf
, 0);
2351 /* If we get EIO on a regset, do not try it again for
2353 disabled_regsets
[regset
- target_regsets
] = 1;
2357 else if (errno
== ESRCH
)
2359 /* At this point, ESRCH should mean the process is
2360 already gone, in which case we simply ignore attempts
2361 to change its registers. See also the related
2362 comment in linux_resume_one_lwp. */
2368 perror ("Warning: ptrace(regsets_store_inferior_registers)");
2371 else if (regset
->type
== GENERAL_REGS
)
2372 saw_general_regs
= 1;
2376 if (saw_general_regs
)
2383 #endif /* HAVE_LINUX_REGSETS */
2387 linux_fetch_registers (int regno
)
2389 #ifdef HAVE_LINUX_REGSETS
2390 if (regsets_fetch_inferior_registers () == 0)
2393 #ifdef HAVE_LINUX_USRREGS
2394 usr_fetch_inferior_registers (regno
);
2399 linux_store_registers (int regno
)
2401 #ifdef HAVE_LINUX_REGSETS
2402 if (regsets_store_inferior_registers () == 0)
2405 #ifdef HAVE_LINUX_USRREGS
2406 usr_store_inferior_registers (regno
);
2411 /* Copy LEN bytes from inferior's memory starting at MEMADDR
2412 to debugger memory starting at MYADDR. */
2415 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
2418 /* Round starting address down to longword boundary. */
2419 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
2420 /* Round ending address up; get number of longwords that makes. */
2422 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2423 / sizeof (PTRACE_XFER_TYPE
);
2424 /* Allocate buffer of that many longwords. */
2425 register PTRACE_XFER_TYPE
*buffer
2426 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
2429 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2431 /* Try using /proc. Don't bother for one word. */
2432 if (len
>= 3 * sizeof (long))
2434 /* We could keep this file open and cache it - possibly one per
2435 thread. That requires some juggling, but is even faster. */
2436 sprintf (filename
, "/proc/%d/mem", pid
);
2437 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
2441 /* If pread64 is available, use it. It's faster if the kernel
2442 supports it (only one syscall), and it's 64-bit safe even on
2443 32-bit platforms (for instance, SPARC debugging a SPARC64
2446 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
2448 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, myaddr
, len
) != len
)
2460 /* Read all the longwords */
2461 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
2464 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
, (PTRACE_ARG3_TYPE
) addr
, 0);
2469 /* Copy appropriate bytes out of the buffer. */
2471 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
2477 /* Copy LEN bytes of data from debugger memory at MYADDR
2478 to inferior's memory at MEMADDR.
2479 On failure (cannot write the inferior)
2480 returns the value of errno. */
2483 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
2486 /* Round starting address down to longword boundary. */
2487 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
2488 /* Round ending address up; get number of longwords that makes. */
2490 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1) / sizeof (PTRACE_XFER_TYPE
);
2491 /* Allocate buffer of that many longwords. */
2492 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
2493 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2497 /* Dump up to four bytes. */
2498 unsigned int val
= * (unsigned int *) myaddr
;
2504 val
= val
& 0xffffff;
2505 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
2506 val
, (long)memaddr
);
2509 /* Fill start and end extra bytes of buffer with existing memory data. */
2511 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
, (PTRACE_ARG3_TYPE
) addr
, 0);
2516 = ptrace (PTRACE_PEEKTEXT
, pid
,
2517 (PTRACE_ARG3_TYPE
) (addr
+ (count
- 1)
2518 * sizeof (PTRACE_XFER_TYPE
)),
2522 /* Copy data to be written over corresponding part of buffer */
2524 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)), myaddr
, len
);
2526 /* Write the entire buffer. */
2528 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
2531 ptrace (PTRACE_POKETEXT
, pid
, (PTRACE_ARG3_TYPE
) addr
, buffer
[i
]);
2539 static int linux_supports_tracefork_flag
;
2541 /* Helper functions for linux_test_for_tracefork, called via clone (). */
2544 linux_tracefork_grandchild (void *arg
)
2549 #define STACK_SIZE 4096
2552 linux_tracefork_child (void *arg
)
2554 ptrace (PTRACE_TRACEME
, 0, 0, 0);
2555 kill (getpid (), SIGSTOP
);
2557 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
2558 CLONE_VM
| SIGCHLD
, NULL
);
2560 clone (linux_tracefork_grandchild
, arg
+ STACK_SIZE
,
2561 CLONE_VM
| SIGCHLD
, NULL
);
2566 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
2567 sure that we can enable the option, and that it had the desired
2571 linux_test_for_tracefork (void)
2573 int child_pid
, ret
, status
;
2575 char *stack
= xmalloc (STACK_SIZE
* 4);
2577 linux_supports_tracefork_flag
= 0;
2579 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
2581 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
2582 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
2584 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
2585 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
2587 if (child_pid
== -1)
2588 perror_with_name ("clone");
2590 ret
= my_waitpid (child_pid
, &status
, 0);
2592 perror_with_name ("waitpid");
2593 else if (ret
!= child_pid
)
2594 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
2595 if (! WIFSTOPPED (status
))
2596 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
2598 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0, PTRACE_O_TRACEFORK
);
2601 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
2604 warning ("linux_test_for_tracefork: failed to kill child");
2608 ret
= my_waitpid (child_pid
, &status
, 0);
2609 if (ret
!= child_pid
)
2610 warning ("linux_test_for_tracefork: failed to wait for killed child");
2611 else if (!WIFSIGNALED (status
))
2612 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
2613 "killed child", status
);
2618 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
2620 warning ("linux_test_for_tracefork: failed to resume child");
2622 ret
= my_waitpid (child_pid
, &status
, 0);
2624 if (ret
== child_pid
&& WIFSTOPPED (status
)
2625 && status
>> 16 == PTRACE_EVENT_FORK
)
2628 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
2629 if (ret
== 0 && second_pid
!= 0)
2633 linux_supports_tracefork_flag
= 1;
2634 my_waitpid (second_pid
, &second_status
, 0);
2635 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
2637 warning ("linux_test_for_tracefork: failed to kill second child");
2638 my_waitpid (second_pid
, &status
, 0);
2642 warning ("linux_test_for_tracefork: unexpected result from waitpid "
2643 "(%d, status 0x%x)", ret
, status
);
2647 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
2649 warning ("linux_test_for_tracefork: failed to kill child");
2650 my_waitpid (child_pid
, &status
, 0);
2652 while (WIFSTOPPED (status
));
2659 linux_look_up_symbols (void)
2661 #ifdef USE_THREAD_DB
2662 struct process_info
*proc
= current_process ();
2664 if (proc
->private->thread_db
!= NULL
)
2667 thread_db_init (!linux_supports_tracefork_flag
);
2672 linux_request_interrupt (void)
2674 extern unsigned long signal_pid
;
2676 if (!ptid_equal (cont_thread
, null_ptid
)
2677 && !ptid_equal (cont_thread
, minus_one_ptid
))
2679 struct lwp_info
*lwp
;
2682 lwp
= get_thread_lwp (current_inferior
);
2683 lwpid
= lwpid_of (lwp
);
2684 kill_lwp (lwpid
, SIGINT
);
2687 kill_lwp (signal_pid
, SIGINT
);
2690 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
2691 to debugger memory starting at MYADDR. */
2694 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
2696 char filename
[PATH_MAX
];
2698 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2700 snprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
2702 fd
= open (filename
, O_RDONLY
);
2706 if (offset
!= (CORE_ADDR
) 0
2707 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
2710 n
= read (fd
, myaddr
, len
);
2717 /* These breakpoint and watchpoint related wrapper functions simply
2718 pass on the function call if the target has registered a
2719 corresponding function. */
2722 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
2724 if (the_low_target
.insert_point
!= NULL
)
2725 return the_low_target
.insert_point (type
, addr
, len
);
2727 /* Unsupported (see target.h). */
2732 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
2734 if (the_low_target
.remove_point
!= NULL
)
2735 return the_low_target
.remove_point (type
, addr
, len
);
2737 /* Unsupported (see target.h). */
2742 linux_stopped_by_watchpoint (void)
2744 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2745 return the_low_target
.stopped_by_watchpoint ();
2751 linux_stopped_data_address (void)
2753 if (the_low_target
.stopped_data_address
!= NULL
)
2754 return the_low_target
.stopped_data_address ();
2759 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
2760 #if defined(__mcoldfire__)
2761 /* These should really be defined in the kernel's ptrace.h header. */
2762 #define PT_TEXT_ADDR 49*4
2763 #define PT_DATA_ADDR 50*4
2764 #define PT_TEXT_END_ADDR 51*4
2767 /* Under uClinux, programs are loaded at non-zero offsets, which we need
2768 to tell gdb about. */
2771 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
2773 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
2774 unsigned long text
, text_end
, data
;
2775 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2779 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
2780 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
2781 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
2785 /* Both text and data offsets produced at compile-time (and so
2786 used by gdb) are relative to the beginning of the program,
2787 with the data segment immediately following the text segment.
2788 However, the actual runtime layout in memory may put the data
2789 somewhere else, so when we send gdb a data base-address, we
2790 use the real data base address and subtract the compile-time
2791 data base-address from it (which is just the length of the
2792 text segment). BSS immediately follows data in both
2795 *data_p
= data
- (text_end
- text
);
2805 linux_qxfer_osdata (const char *annex
,
2806 unsigned char *readbuf
, unsigned const char *writebuf
,
2807 CORE_ADDR offset
, int len
)
2809 /* We make the process list snapshot when the object starts to be
2811 static const char *buf
;
2812 static long len_avail
= -1;
2813 static struct buffer buffer
;
2817 if (strcmp (annex
, "processes") != 0)
2820 if (!readbuf
|| writebuf
)
2825 if (len_avail
!= -1 && len_avail
!= 0)
2826 buffer_free (&buffer
);
2829 buffer_init (&buffer
);
2830 buffer_grow_str (&buffer
, "<osdata type=\"processes\">");
2832 dirp
= opendir ("/proc");
2836 while ((dp
= readdir (dirp
)) != NULL
)
2838 struct stat statbuf
;
2839 char procentry
[sizeof ("/proc/4294967295")];
2841 if (!isdigit (dp
->d_name
[0])
2842 || strlen (dp
->d_name
) > sizeof ("4294967295") - 1)
2845 sprintf (procentry
, "/proc/%s", dp
->d_name
);
2846 if (stat (procentry
, &statbuf
) == 0
2847 && S_ISDIR (statbuf
.st_mode
))
2851 char cmd
[MAXPATHLEN
+ 1];
2852 struct passwd
*entry
;
2854 sprintf (pathname
, "/proc/%s/cmdline", dp
->d_name
);
2855 entry
= getpwuid (statbuf
.st_uid
);
2857 if ((f
= fopen (pathname
, "r")) != NULL
)
2859 size_t len
= fread (cmd
, 1, sizeof (cmd
) - 1, f
);
2863 for (i
= 0; i
< len
; i
++)
2871 "<column name=\"pid\">%s</column>"
2872 "<column name=\"user\">%s</column>"
2873 "<column name=\"command\">%s</column>"
2876 entry
? entry
->pw_name
: "?",
2886 buffer_grow_str0 (&buffer
, "</osdata>\n");
2887 buf
= buffer_finish (&buffer
);
2888 len_avail
= strlen (buf
);
2891 if (offset
>= len_avail
)
2893 /* Done. Get rid of the data. */
2894 buffer_free (&buffer
);
2900 if (len
> len_avail
- offset
)
2901 len
= len_avail
- offset
;
2902 memcpy (readbuf
, buf
+ offset
, len
);
2907 /* Convert a native/host siginfo object, into/from the siginfo in the
2908 layout of the inferiors' architecture. */
2911 siginfo_fixup (struct siginfo
*siginfo
, void *inf_siginfo
, int direction
)
2915 if (the_low_target
.siginfo_fixup
!= NULL
)
2916 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
2918 /* If there was no callback, or the callback didn't do anything,
2919 then just do a straight memcpy. */
2923 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
2925 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
2930 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
2931 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
2934 struct siginfo siginfo
;
2935 char inf_siginfo
[sizeof (struct siginfo
)];
2937 if (current_inferior
== NULL
)
2940 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2943 fprintf (stderr
, "%s siginfo for lwp %d.\n",
2944 readbuf
!= NULL
? "Reading" : "Writing",
2947 if (offset
> sizeof (siginfo
))
2950 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
2953 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
2954 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
2955 inferior with a 64-bit GDBSERVER should look the same as debugging it
2956 with a 32-bit GDBSERVER, we need to convert it. */
2957 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
2959 if (offset
+ len
> sizeof (siginfo
))
2960 len
= sizeof (siginfo
) - offset
;
2962 if (readbuf
!= NULL
)
2963 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
2966 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
2968 /* Convert back to ptrace layout before flushing it out. */
2969 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
2971 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
2978 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
2979 so we notice when children change state; as the handler for the
2980 sigsuspend in my_waitpid. */
2983 sigchld_handler (int signo
)
2985 int old_errno
= errno
;
2988 /* fprintf is not async-signal-safe, so call write directly. */
2989 write (2, "sigchld_handler\n", sizeof ("sigchld_handler\n") - 1);
2991 if (target_is_async_p ())
2992 async_file_mark (); /* trigger a linux_wait */
2998 linux_supports_non_stop (void)
3004 linux_async (int enable
)
3006 int previous
= (linux_event_pipe
[0] != -1);
3008 if (previous
!= enable
)
3011 sigemptyset (&mask
);
3012 sigaddset (&mask
, SIGCHLD
);
3014 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
3018 if (pipe (linux_event_pipe
) == -1)
3019 fatal ("creating event pipe failed.");
3021 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
3022 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
3024 /* Register the event loop handler. */
3025 add_file_handler (linux_event_pipe
[0],
3026 handle_target_event
, NULL
);
3028 /* Always trigger a linux_wait. */
3033 delete_file_handler (linux_event_pipe
[0]);
3035 close (linux_event_pipe
[0]);
3036 close (linux_event_pipe
[1]);
3037 linux_event_pipe
[0] = -1;
3038 linux_event_pipe
[1] = -1;
3041 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
3048 linux_start_non_stop (int nonstop
)
3050 /* Register or unregister from event-loop accordingly. */
3051 linux_async (nonstop
);
3056 linux_supports_multi_process (void)
3062 /* Enumerate spufs IDs for process PID. */
3064 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
3070 struct dirent
*entry
;
3072 sprintf (path
, "/proc/%ld/fd", pid
);
3073 dir
= opendir (path
);
3078 while ((entry
= readdir (dir
)) != NULL
)
3084 fd
= atoi (entry
->d_name
);
3088 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
3089 if (stat (path
, &st
) != 0)
3091 if (!S_ISDIR (st
.st_mode
))
3094 if (statfs (path
, &stfs
) != 0)
3096 if (stfs
.f_type
!= SPUFS_MAGIC
)
3099 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
3101 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
3111 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
3112 object type, using the /proc file system. */
3114 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
3115 unsigned const char *writebuf
,
3116 CORE_ADDR offset
, int len
)
3118 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
3123 if (!writebuf
&& !readbuf
)
3131 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
3134 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
3135 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
3140 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
3147 ret
= write (fd
, writebuf
, (size_t) len
);
3149 ret
= read (fd
, readbuf
, (size_t) len
);
3155 static struct target_ops linux_target_ops
= {
3156 linux_create_inferior
,
3164 linux_fetch_registers
,
3165 linux_store_registers
,
3168 linux_look_up_symbols
,
3169 linux_request_interrupt
,
3173 linux_stopped_by_watchpoint
,
3174 linux_stopped_data_address
,
3175 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
3180 #ifdef USE_THREAD_DB
3181 thread_db_get_tls_address
,
3186 hostio_last_error_from_errno
,
3189 linux_supports_non_stop
,
3191 linux_start_non_stop
,
3192 linux_supports_multi_process
,
3193 #ifdef USE_THREAD_DB
3194 thread_db_handle_monitor_command
3201 linux_init_signals ()
3203 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
3204 to find what the cancel signal actually is. */
3205 signal (__SIGRTMIN
+1, SIG_IGN
);
3209 initialize_low (void)
3211 struct sigaction sigchld_action
;
3212 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
3213 set_target_ops (&linux_target_ops
);
3214 set_breakpoint_data (the_low_target
.breakpoint
,
3215 the_low_target
.breakpoint_len
);
3216 linux_init_signals ();
3217 linux_test_for_tracefork ();
3218 #ifdef HAVE_LINUX_REGSETS
3219 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
3221 disabled_regsets
= xmalloc (num_regsets
);
3224 sigchld_action
.sa_handler
= sigchld_handler
;
3225 sigemptyset (&sigchld_action
.sa_mask
);
3226 sigchld_action
.sa_flags
= SA_RESTART
;
3227 sigaction (SIGCHLD
, &sigchld_action
, NULL
);