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 #define W_STOPCODE(sig) ((sig) << 8 | 0x7f)
101 #if !(defined(__UCLIBC_HAS_MMU__) || defined(__ARCH_HAS_MMU__))
106 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
107 representation of the thread ID.
109 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
110 the same as the LWP ID.
112 ``all_processes'' is keyed by the "overall process ID", which
113 GNU/Linux calls tgid, "thread group ID". */
115 struct inferior_list all_lwps
;
117 /* A list of all unknown processes which receive stop signals. Some other
118 process will presumably claim each of these as forked children
121 struct inferior_list stopped_pids
;
123 /* FIXME this is a bit of a hack, and could be removed. */
124 int stopping_threads
;
126 /* FIXME make into a target method? */
127 int using_threads
= 1;
129 /* This flag is true iff we've just created or attached to our first
130 inferior but it has not stopped yet. As soon as it does, we need
131 to call the low target's arch_setup callback. Doing this only on
132 the first inferior avoids reinializing the architecture on every
133 inferior, and avoids messing with the register caches of the
134 already running inferiors. NOTE: this assumes all inferiors under
135 control of gdbserver have the same architecture. */
136 static int new_inferior
;
138 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
139 int step
, int signal
, siginfo_t
*info
);
140 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
141 static void stop_all_lwps (void);
142 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
143 static int check_removed_breakpoint (struct lwp_info
*event_child
);
144 static void *add_lwp (ptid_t ptid
);
145 static int linux_stopped_by_watchpoint (void);
146 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
147 static int linux_core_of_thread (ptid_t ptid
);
149 struct pending_signals
153 struct pending_signals
*prev
;
156 #define PTRACE_ARG3_TYPE void *
157 #define PTRACE_ARG4_TYPE void *
158 #define PTRACE_XFER_TYPE long
160 #ifdef HAVE_LINUX_REGSETS
161 static char *disabled_regsets
;
162 static int num_regsets
;
165 /* The read/write ends of the pipe registered as waitable file in the
167 static int linux_event_pipe
[2] = { -1, -1 };
169 /* True if we're currently in async mode. */
170 #define target_is_async_p() (linux_event_pipe[0] != -1)
172 static void send_sigstop (struct inferior_list_entry
*entry
);
173 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
175 /* Accepts an integer PID; Returns a string representing a file that
176 can be opened to get info for the child process.
177 Space for the result is malloc'd, caller must free. */
180 linux_child_pid_to_exec_file (int pid
)
184 name1
= xmalloc (MAXPATHLEN
);
185 name2
= xmalloc (MAXPATHLEN
);
186 memset (name2
, 0, MAXPATHLEN
);
188 sprintf (name1
, "/proc/%d/exe", pid
);
189 if (readlink (name1
, name2
, MAXPATHLEN
) > 0)
201 /* Return non-zero if HEADER is a 64-bit ELF file. */
204 elf_64_header_p (const Elf64_Ehdr
*header
)
206 return (header
->e_ident
[EI_MAG0
] == ELFMAG0
207 && header
->e_ident
[EI_MAG1
] == ELFMAG1
208 && header
->e_ident
[EI_MAG2
] == ELFMAG2
209 && header
->e_ident
[EI_MAG3
] == ELFMAG3
210 && header
->e_ident
[EI_CLASS
] == ELFCLASS64
);
213 /* Return non-zero if FILE is a 64-bit ELF file,
214 zero if the file is not a 64-bit ELF file,
215 and -1 if the file is not accessible or doesn't exist. */
218 elf_64_file_p (const char *file
)
223 fd
= open (file
, O_RDONLY
);
227 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
234 return elf_64_header_p (&header
);
238 delete_lwp (struct lwp_info
*lwp
)
240 remove_thread (get_lwp_thread (lwp
));
241 remove_inferior (&all_lwps
, &lwp
->head
);
242 free (lwp
->arch_private
);
246 /* Add a process to the common process list, and set its private
249 static struct process_info
*
250 linux_add_process (int pid
, int attached
)
252 struct process_info
*proc
;
254 /* Is this the first process? If so, then set the arch. */
255 if (all_processes
.head
== NULL
)
258 proc
= add_process (pid
, attached
);
259 proc
->private = xcalloc (1, sizeof (*proc
->private));
261 if (the_low_target
.new_process
!= NULL
)
262 proc
->private->arch_private
= the_low_target
.new_process ();
267 /* Remove a process from the common process list,
268 also freeing all private data. */
271 linux_remove_process (struct process_info
*process
)
273 struct process_info_private
*priv
= process
->private;
275 free (priv
->arch_private
);
277 remove_process (process
);
280 /* Wrapper function for waitpid which handles EINTR, and emulates
281 __WALL for systems where that is not available. */
284 my_waitpid (int pid
, int *status
, int flags
)
289 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
293 sigset_t block_mask
, org_mask
, wake_mask
;
296 wnohang
= (flags
& WNOHANG
) != 0;
297 flags
&= ~(__WALL
| __WCLONE
);
300 /* Block all signals while here. This avoids knowing about
301 LinuxThread's signals. */
302 sigfillset (&block_mask
);
303 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
305 /* ... except during the sigsuspend below. */
306 sigemptyset (&wake_mask
);
310 /* Since all signals are blocked, there's no need to check
312 ret
= waitpid (pid
, status
, flags
);
315 if (ret
== -1 && out_errno
!= ECHILD
)
320 if (flags
& __WCLONE
)
322 /* We've tried both flavors now. If WNOHANG is set,
323 there's nothing else to do, just bail out. */
328 fprintf (stderr
, "blocking\n");
330 /* Block waiting for signals. */
331 sigsuspend (&wake_mask
);
337 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
342 ret
= waitpid (pid
, status
, flags
);
343 while (ret
== -1 && errno
== EINTR
);
348 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
349 pid
, flags
, status
? *status
: -1, ret
);
355 /* Handle a GNU/Linux extended wait response. If we see a clone
356 event, we need to add the new LWP to our list (and not report the
357 trap to higher layers). */
360 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
362 int event
= wstat
>> 16;
363 struct lwp_info
*new_lwp
;
365 if (event
== PTRACE_EVENT_CLONE
)
368 unsigned long new_pid
;
369 int ret
, status
= W_STOPCODE (SIGSTOP
);
371 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), 0, &new_pid
);
373 /* If we haven't already seen the new PID stop, wait for it now. */
374 if (! pull_pid_from_list (&stopped_pids
, new_pid
))
376 /* The new child has a pending SIGSTOP. We can't affect it until it
377 hits the SIGSTOP, but we're already attached. */
379 ret
= my_waitpid (new_pid
, &status
, __WALL
);
382 perror_with_name ("waiting for new child");
383 else if (ret
!= new_pid
)
384 warning ("wait returned unexpected PID %d", ret
);
385 else if (!WIFSTOPPED (status
))
386 warning ("wait returned unexpected status 0x%x", status
);
389 ptrace (PTRACE_SETOPTIONS
, new_pid
, 0, (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
391 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
392 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
393 add_thread (ptid
, new_lwp
);
395 /* Either we're going to immediately resume the new thread
396 or leave it stopped. linux_resume_one_lwp is a nop if it
397 thinks the thread is currently running, so set this first
398 before calling linux_resume_one_lwp. */
399 new_lwp
->stopped
= 1;
401 /* Normally we will get the pending SIGSTOP. But in some cases
402 we might get another signal delivered to the group first.
403 If we do get another signal, be sure not to lose it. */
404 if (WSTOPSIG (status
) == SIGSTOP
)
406 if (! stopping_threads
)
407 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
411 new_lwp
->stop_expected
= 1;
412 if (stopping_threads
)
414 new_lwp
->status_pending_p
= 1;
415 new_lwp
->status_pending
= status
;
418 /* Pass the signal on. This is what GDB does - except
419 shouldn't we really report it instead? */
420 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
423 /* Always resume the current thread. If we are stopping
424 threads, it will have a pending SIGSTOP; we may as well
426 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
430 /* This function should only be called if the process got a SIGTRAP.
431 The SIGTRAP could mean several things.
433 On i386, where decr_pc_after_break is non-zero:
434 If we were single-stepping this process using PTRACE_SINGLESTEP,
435 we will get only the one SIGTRAP (even if the instruction we
436 stepped over was a breakpoint). The value of $eip will be the
438 If we continue the process using PTRACE_CONT, we will get a
439 SIGTRAP when we hit a breakpoint. The value of $eip will be
440 the instruction after the breakpoint (i.e. needs to be
441 decremented). If we report the SIGTRAP to GDB, we must also
442 report the undecremented PC. If we cancel the SIGTRAP, we
443 must resume at the decremented PC.
445 (Presumably, not yet tested) On a non-decr_pc_after_break machine
446 with hardware or kernel single-step:
447 If we single-step over a breakpoint instruction, our PC will
448 point at the following instruction. If we continue and hit a
449 breakpoint instruction, our PC will point at the breakpoint
455 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
456 CORE_ADDR stop_pc
= (*the_low_target
.get_pc
) (regcache
);
458 if (! get_thread_lwp (current_inferior
)->stepping
)
459 stop_pc
-= the_low_target
.decr_pc_after_break
;
462 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
468 add_lwp (ptid_t ptid
)
470 struct lwp_info
*lwp
;
472 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
473 memset (lwp
, 0, sizeof (*lwp
));
477 if (the_low_target
.new_thread
!= NULL
)
478 lwp
->arch_private
= the_low_target
.new_thread ();
480 add_inferior_to_list (&all_lwps
, &lwp
->head
);
485 /* Start an inferior process and returns its pid.
486 ALLARGS is a vector of program-name and args. */
489 linux_create_inferior (char *program
, char **allargs
)
491 struct lwp_info
*new_lwp
;
495 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
501 perror_with_name ("fork");
505 ptrace (PTRACE_TRACEME
, 0, 0, 0);
507 #ifdef __SIGRTMIN /* Bionic doesn't use SIGRTMIN the way glibc does. */
508 signal (__SIGRTMIN
+ 1, SIG_DFL
);
513 execv (program
, allargs
);
515 execvp (program
, allargs
);
517 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
523 linux_add_process (pid
, 0);
525 ptid
= ptid_build (pid
, pid
, 0);
526 new_lwp
= add_lwp (ptid
);
527 add_thread (ptid
, new_lwp
);
528 new_lwp
->must_set_ptrace_flags
= 1;
533 /* Attach to an inferior process. */
536 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
539 struct lwp_info
*new_lwp
;
541 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) != 0)
545 /* If we fail to attach to an LWP, just warn. */
546 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
547 strerror (errno
), errno
);
552 /* If we fail to attach to a process, report an error. */
553 error ("Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
554 strerror (errno
), errno
);
558 /* NOTE/FIXME: This lwp might have not been the tgid. */
559 ptid
= ptid_build (lwpid
, lwpid
, 0);
562 /* Note that extracting the pid from the current inferior is
563 safe, since we're always called in the context of the same
564 process as this new thread. */
565 int pid
= pid_of (get_thread_lwp (current_inferior
));
566 ptid
= ptid_build (pid
, lwpid
, 0);
569 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
570 add_thread (ptid
, new_lwp
);
572 /* We need to wait for SIGSTOP before being able to make the next
573 ptrace call on this LWP. */
574 new_lwp
->must_set_ptrace_flags
= 1;
576 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
579 There are several cases to consider here:
581 1) gdbserver has already attached to the process and is being notified
582 of a new thread that is being created.
583 In this case we should ignore that SIGSTOP and resume the process.
584 This is handled below by setting stop_expected = 1.
586 2) This is the first thread (the process thread), and we're attaching
587 to it via attach_inferior.
588 In this case we want the process thread to stop.
589 This is handled by having linux_attach clear stop_expected after
591 ??? If the process already has several threads we leave the other
594 3) GDB is connecting to gdbserver and is requesting an enumeration of all
596 In this case we want the thread to stop.
597 FIXME: This case is currently not properly handled.
598 We should wait for the SIGSTOP but don't. Things work apparently
599 because enough time passes between when we ptrace (ATTACH) and when
600 gdb makes the next ptrace call on the thread.
602 On the other hand, if we are currently trying to stop all threads, we
603 should treat the new thread as if we had sent it a SIGSTOP. This works
604 because we are guaranteed that the add_lwp call above added us to the
605 end of the list, and so the new thread has not yet reached
606 wait_for_sigstop (but will). */
607 if (! stopping_threads
)
608 new_lwp
->stop_expected
= 1;
612 linux_attach_lwp (unsigned long lwpid
)
614 linux_attach_lwp_1 (lwpid
, 0);
618 linux_attach (unsigned long pid
)
620 struct lwp_info
*lwp
;
622 linux_attach_lwp_1 (pid
, 1);
624 linux_add_process (pid
, 1);
628 /* Don't ignore the initial SIGSTOP if we just attached to this
629 process. It will be collected by wait shortly. */
630 lwp
= (struct lwp_info
*) find_inferior_id (&all_lwps
,
631 ptid_build (pid
, pid
, 0));
632 lwp
->stop_expected
= 0;
645 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
647 struct counter
*counter
= args
;
649 if (ptid_get_pid (entry
->id
) == counter
->pid
)
651 if (++counter
->count
> 1)
659 last_thread_of_process_p (struct thread_info
*thread
)
661 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
662 int pid
= ptid_get_pid (ptid
);
663 struct counter counter
= { pid
, 0 };
665 return (find_inferior (&all_threads
,
666 second_thread_of_pid_p
, &counter
) == NULL
);
669 /* Kill the inferior lwp. */
672 linux_kill_one_lwp (struct inferior_list_entry
*entry
, void *args
)
674 struct thread_info
*thread
= (struct thread_info
*) entry
;
675 struct lwp_info
*lwp
= get_thread_lwp (thread
);
677 int pid
= * (int *) args
;
679 if (ptid_get_pid (entry
->id
) != pid
)
682 /* We avoid killing the first thread here, because of a Linux kernel (at
683 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
684 the children get a chance to be reaped, it will remain a zombie
687 if (lwpid_of (lwp
) == pid
)
690 fprintf (stderr
, "lkop: is last of process %s\n",
691 target_pid_to_str (entry
->id
));
695 /* If we're killing a running inferior, make sure it is stopped
696 first, as PTRACE_KILL will not work otherwise. */
698 send_sigstop (&lwp
->head
);
702 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
704 /* Make sure it died. The loop is most likely unnecessary. */
705 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
706 } while (pid
> 0 && WIFSTOPPED (wstat
));
714 struct process_info
*process
;
715 struct lwp_info
*lwp
;
716 struct thread_info
*thread
;
720 process
= find_process_pid (pid
);
724 find_inferior (&all_threads
, linux_kill_one_lwp
, &pid
);
726 /* See the comment in linux_kill_one_lwp. We did not kill the first
727 thread in the list, so do so now. */
728 lwp
= find_lwp_pid (pid_to_ptid (pid
));
729 thread
= get_lwp_thread (lwp
);
732 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
733 lwpid_of (lwp
), pid
);
735 /* If we're killing a running inferior, make sure it is stopped
736 first, as PTRACE_KILL will not work otherwise. */
738 send_sigstop (&lwp
->head
);
742 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
744 /* Make sure it died. The loop is most likely unnecessary. */
745 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
746 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
749 thread_db_free (process
, 0);
752 linux_remove_process (process
);
757 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
759 struct thread_info
*thread
= (struct thread_info
*) entry
;
760 struct lwp_info
*lwp
= get_thread_lwp (thread
);
761 int pid
= * (int *) args
;
763 if (ptid_get_pid (entry
->id
) != pid
)
766 /* If we're detaching from a running inferior, make sure it is
767 stopped first, as PTRACE_DETACH will not work otherwise. */
770 int lwpid
= lwpid_of (lwp
);
772 stopping_threads
= 1;
773 send_sigstop (&lwp
->head
);
775 /* If this detects a new thread through a clone event, the new
776 thread is appended to the end of the lwp list, so we'll
777 eventually detach from it. */
778 wait_for_sigstop (&lwp
->head
);
779 stopping_threads
= 0;
781 /* If LWP exits while we're trying to stop it, there's nothing
783 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
788 /* Make sure the process isn't stopped at a breakpoint that's
790 check_removed_breakpoint (lwp
);
792 /* If this process is stopped but is expecting a SIGSTOP, then make
793 sure we take care of that now. This isn't absolutely guaranteed
794 to collect the SIGSTOP, but is fairly likely to. */
795 if (lwp
->stop_expected
)
798 /* Clear stop_expected, so that the SIGSTOP will be reported. */
799 lwp
->stop_expected
= 0;
801 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
802 linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
805 /* Flush any pending changes to the process's registers. */
806 regcache_invalidate_one ((struct inferior_list_entry
*)
807 get_lwp_thread (lwp
));
809 /* Finally, let it resume. */
810 ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0, 0);
817 any_thread_of (struct inferior_list_entry
*entry
, void *args
)
821 if (ptid_get_pid (entry
->id
) == *pid_p
)
828 linux_detach (int pid
)
830 struct process_info
*process
;
832 process
= find_process_pid (pid
);
837 thread_db_free (process
, 1);
841 (struct thread_info
*) find_inferior (&all_threads
, any_thread_of
, &pid
);
843 delete_all_breakpoints ();
844 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
845 linux_remove_process (process
);
853 struct process_info
*process
;
855 process
= find_process_pid (pid
);
860 ret
= my_waitpid (pid
, &status
, 0);
861 if (WIFEXITED (status
) || WIFSIGNALED (status
))
863 } while (ret
!= -1 || errno
!= ECHILD
);
866 /* Return nonzero if the given thread is still alive. */
868 linux_thread_alive (ptid_t ptid
)
870 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
872 /* We assume we always know if a thread exits. If a whole process
873 exited but we still haven't been able to report it to GDB, we'll
874 hold on to the last lwp of the dead process. */
881 /* Return nonzero if this process stopped at a breakpoint which
882 no longer appears to be inserted. Also adjust the PC
883 appropriately to resume where the breakpoint used to be. */
885 check_removed_breakpoint (struct lwp_info
*event_child
)
888 struct thread_info
*saved_inferior
;
889 struct regcache
*regcache
;
891 if (event_child
->pending_is_breakpoint
== 0)
895 fprintf (stderr
, "Checking for breakpoint in lwp %ld.\n",
896 lwpid_of (event_child
));
898 saved_inferior
= current_inferior
;
899 current_inferior
= get_lwp_thread (event_child
);
900 regcache
= get_thread_regcache (current_inferior
, 1);
901 stop_pc
= get_stop_pc ();
903 /* If the PC has changed since we stopped, then we shouldn't do
904 anything. This happens if, for instance, GDB handled the
905 decr_pc_after_break subtraction itself. */
906 if (stop_pc
!= event_child
->pending_stop_pc
)
909 fprintf (stderr
, "Ignoring, PC was changed. Old PC was 0x%08llx\n",
910 event_child
->pending_stop_pc
);
912 event_child
->pending_is_breakpoint
= 0;
913 current_inferior
= saved_inferior
;
917 /* If the breakpoint is still there, we will report hitting it. */
918 if ((*the_low_target
.breakpoint_at
) (stop_pc
))
921 fprintf (stderr
, "Ignoring, breakpoint is still present.\n");
922 current_inferior
= saved_inferior
;
927 fprintf (stderr
, "Removed breakpoint.\n");
929 /* For decr_pc_after_break targets, here is where we perform the
930 decrement. We go immediately from this function to resuming,
931 and can not safely call get_stop_pc () again. */
932 if (the_low_target
.set_pc
!= NULL
)
935 fprintf (stderr
, "Set pc to 0x%lx\n", (long) stop_pc
);
936 (*the_low_target
.set_pc
) (regcache
, stop_pc
);
939 /* We consumed the pending SIGTRAP. */
940 event_child
->pending_is_breakpoint
= 0;
941 event_child
->status_pending_p
= 0;
942 event_child
->status_pending
= 0;
944 current_inferior
= saved_inferior
;
948 /* Return 1 if this lwp has an interesting status pending. This
949 function may silently resume an inferior lwp. */
951 status_pending_p (struct inferior_list_entry
*entry
, void *arg
)
953 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
954 ptid_t ptid
= * (ptid_t
*) arg
;
956 /* Check if we're only interested in events from a specific process
958 if (!ptid_equal (minus_one_ptid
, ptid
)
959 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
962 if (lwp
->status_pending_p
&& !lwp
->suspended
)
963 if (check_removed_breakpoint (lwp
))
965 /* This thread was stopped at a breakpoint, and the breakpoint
966 is now gone. We were told to continue (or step...) all threads,
967 so GDB isn't trying to single-step past this breakpoint.
968 So instead of reporting the old SIGTRAP, pretend we got to
969 the breakpoint just after it was removed instead of just
970 before; resume the process. */
971 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
975 return (lwp
->status_pending_p
&& !lwp
->suspended
);
979 same_lwp (struct inferior_list_entry
*entry
, void *data
)
981 ptid_t ptid
= *(ptid_t
*) data
;
984 if (ptid_get_lwp (ptid
) != 0)
985 lwp
= ptid_get_lwp (ptid
);
987 lwp
= ptid_get_pid (ptid
);
989 if (ptid_get_lwp (entry
->id
) == lwp
)
996 find_lwp_pid (ptid_t ptid
)
998 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
1001 static struct lwp_info
*
1002 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
1005 int to_wait_for
= -1;
1006 struct lwp_info
*child
= NULL
;
1009 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1011 if (ptid_equal (ptid
, minus_one_ptid
))
1012 to_wait_for
= -1; /* any child */
1014 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1020 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1021 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1024 perror_with_name ("waitpid");
1027 && (!WIFSTOPPED (*wstatp
)
1028 || (WSTOPSIG (*wstatp
) != 32
1029 && WSTOPSIG (*wstatp
) != 33)))
1030 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1032 child
= find_lwp_pid (pid_to_ptid (ret
));
1034 /* If we didn't find a process, one of two things presumably happened:
1035 - A process we started and then detached from has exited. Ignore it.
1036 - A process we are controlling has forked and the new child's stop
1037 was reported to us by the kernel. Save its PID. */
1038 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1040 add_pid_to_list (&stopped_pids
, ret
);
1043 else if (child
== NULL
)
1047 child
->pending_is_breakpoint
= 0;
1049 child
->last_status
= *wstatp
;
1051 /* Architecture-specific setup after inferior is running.
1052 This needs to happen after we have attached to the inferior
1053 and it is stopped for the first time, but before we access
1054 any inferior registers. */
1057 the_low_target
.arch_setup ();
1058 #ifdef HAVE_LINUX_REGSETS
1059 memset (disabled_regsets
, 0, num_regsets
);
1065 && WIFSTOPPED (*wstatp
)
1066 && the_low_target
.get_pc
!= NULL
)
1068 struct thread_info
*saved_inferior
= current_inferior
;
1069 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
1072 current_inferior
= (struct thread_info
*)
1073 find_inferior_id (&all_threads
, child
->head
.id
);
1074 pc
= (*the_low_target
.get_pc
) (regcache
);
1075 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1076 current_inferior
= saved_inferior
;
1082 /* Wait for an event from child PID. If PID is -1, wait for any
1083 child. Store the stop status through the status pointer WSTAT.
1084 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1085 event was found and OPTIONS contains WNOHANG. Return the PID of
1086 the stopped child otherwise. */
1089 linux_wait_for_event_1 (ptid_t ptid
, int *wstat
, int options
)
1092 struct lwp_info
*event_child
= NULL
;
1094 struct lwp_info
*requested_child
= NULL
;
1096 /* Check for a lwp with a pending status. */
1097 /* It is possible that the user changed the pending task's registers since
1098 it stopped. We correctly handle the change of PC if we hit a breakpoint
1099 (in check_removed_breakpoint); signals should be reported anyway. */
1101 if (ptid_equal (ptid
, minus_one_ptid
)
1102 || ptid_equal (pid_to_ptid (ptid_get_pid (ptid
)), ptid
))
1104 event_child
= (struct lwp_info
*)
1105 find_inferior (&all_lwps
, status_pending_p
, &ptid
);
1106 if (debug_threads
&& event_child
)
1107 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1111 requested_child
= find_lwp_pid (ptid
);
1112 if (requested_child
->status_pending_p
1113 && !check_removed_breakpoint (requested_child
))
1114 event_child
= requested_child
;
1117 if (event_child
!= NULL
)
1120 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1121 lwpid_of (event_child
), event_child
->status_pending
);
1122 *wstat
= event_child
->status_pending
;
1123 event_child
->status_pending_p
= 0;
1124 event_child
->status_pending
= 0;
1125 current_inferior
= get_lwp_thread (event_child
);
1126 return lwpid_of (event_child
);
1129 /* We only enter this loop if no process has a pending wait status. Thus
1130 any action taken in response to a wait status inside this loop is
1131 responding as soon as we detect the status, not after any pending
1135 event_child
= linux_wait_for_lwp (ptid
, wstat
, options
);
1137 if ((options
& WNOHANG
) && event_child
== NULL
)
1140 if (event_child
== NULL
)
1141 error ("event from unknown child");
1143 current_inferior
= get_lwp_thread (event_child
);
1145 /* Check for thread exit. */
1146 if (! WIFSTOPPED (*wstat
))
1149 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1151 /* If the last thread is exiting, just return. */
1152 if (last_thread_of_process_p (current_inferior
))
1155 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1156 lwpid_of (event_child
));
1157 return lwpid_of (event_child
);
1160 delete_lwp (event_child
);
1164 current_inferior
= (struct thread_info
*) all_threads
.head
;
1166 fprintf (stderr
, "Current inferior is now %ld\n",
1167 lwpid_of (get_thread_lwp (current_inferior
)));
1171 current_inferior
= NULL
;
1173 fprintf (stderr
, "Current inferior is now <NULL>\n");
1176 /* If we were waiting for this particular child to do something...
1177 well, it did something. */
1178 if (requested_child
!= NULL
)
1179 return lwpid_of (event_child
);
1181 /* Wait for a more interesting event. */
1185 if (event_child
->must_set_ptrace_flags
)
1187 ptrace (PTRACE_SETOPTIONS
, lwpid_of (event_child
),
1188 0, (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
1189 event_child
->must_set_ptrace_flags
= 0;
1192 if (WIFSTOPPED (*wstat
)
1193 && WSTOPSIG (*wstat
) == SIGSTOP
1194 && event_child
->stop_expected
)
1197 fprintf (stderr
, "Expected stop.\n");
1198 event_child
->stop_expected
= 0;
1199 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
1203 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1204 && *wstat
>> 16 != 0)
1206 handle_extended_wait (event_child
, *wstat
);
1210 /* If GDB is not interested in this signal, don't stop other
1211 threads, and don't report it to GDB. Just resume the
1212 inferior right away. We do this for threading-related
1213 signals as well as any that GDB specifically requested we
1214 ignore. But never ignore SIGSTOP if we sent it ourselves,
1215 and do not ignore signals when stepping - they may require
1216 special handling to skip the signal handler. */
1217 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
1219 if (WIFSTOPPED (*wstat
)
1220 && !event_child
->stepping
1222 #if defined (USE_THREAD_DB) && defined (__SIGRTMIN)
1223 (current_process ()->private->thread_db
!= NULL
1224 && (WSTOPSIG (*wstat
) == __SIGRTMIN
1225 || WSTOPSIG (*wstat
) == __SIGRTMIN
+ 1))
1228 (pass_signals
[target_signal_from_host (WSTOPSIG (*wstat
))]
1229 && (WSTOPSIG (*wstat
) != SIGSTOP
|| !stopping_threads
))))
1231 siginfo_t info
, *info_p
;
1234 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
1235 WSTOPSIG (*wstat
), lwpid_of (event_child
));
1237 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
1241 linux_resume_one_lwp (event_child
,
1242 event_child
->stepping
,
1243 WSTOPSIG (*wstat
), info_p
);
1247 /* If this event was not handled above, and is not a SIGTRAP, report
1249 if (!WIFSTOPPED (*wstat
) || WSTOPSIG (*wstat
) != SIGTRAP
)
1250 return lwpid_of (event_child
);
1252 /* If this target does not support breakpoints, we simply report the
1253 SIGTRAP; it's of no concern to us. */
1254 if (the_low_target
.get_pc
== NULL
)
1255 return lwpid_of (event_child
);
1257 stop_pc
= get_stop_pc ();
1259 /* bp_reinsert will only be set if we were single-stepping.
1260 Notice that we will resume the process after hitting
1261 a gdbserver breakpoint; single-stepping to/over one
1262 is not supported (yet). */
1263 if (event_child
->bp_reinsert
!= 0)
1266 fprintf (stderr
, "Reinserted breakpoint.\n");
1267 reinsert_breakpoint (event_child
->bp_reinsert
);
1268 event_child
->bp_reinsert
= 0;
1270 /* Clear the single-stepping flag and SIGTRAP as we resume. */
1271 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1275 bp_status
= check_breakpoints (stop_pc
);
1280 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
1282 /* We hit one of our own breakpoints. We mark it as a pending
1283 breakpoint, so that check_removed_breakpoint () will do the PC
1284 adjustment for us at the appropriate time. */
1285 event_child
->pending_is_breakpoint
= 1;
1286 event_child
->pending_stop_pc
= stop_pc
;
1288 /* We may need to put the breakpoint back. We continue in the event
1289 loop instead of simply replacing the breakpoint right away,
1290 in order to not lose signals sent to the thread that hit the
1291 breakpoint. Unfortunately this increases the window where another
1292 thread could sneak past the removed breakpoint. For the current
1293 use of server-side breakpoints (thread creation) this is
1294 acceptable; but it needs to be considered before this breakpoint
1295 mechanism can be used in more general ways. For some breakpoints
1296 it may be necessary to stop all other threads, but that should
1297 be avoided where possible.
1299 If breakpoint_reinsert_addr is NULL, that means that we can
1300 use PTRACE_SINGLESTEP on this platform. Uninsert the breakpoint,
1301 mark it for reinsertion, and single-step.
1303 Otherwise, call the target function to figure out where we need
1304 our temporary breakpoint, create it, and continue executing this
1307 /* NOTE: we're lifting breakpoints in non-stop mode. This
1308 is currently only used for thread event breakpoints, so
1309 it isn't that bad as long as we have PTRACE_EVENT_CLONE
1312 /* No need to reinsert. */
1313 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1314 else if (the_low_target
.breakpoint_reinsert_addr
== NULL
)
1316 event_child
->bp_reinsert
= stop_pc
;
1317 uninsert_breakpoint (stop_pc
);
1318 linux_resume_one_lwp (event_child
, 1, 0, NULL
);
1322 reinsert_breakpoint_by_bp
1323 (stop_pc
, (*the_low_target
.breakpoint_reinsert_addr
) ());
1324 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1331 fprintf (stderr
, "Hit a non-gdbserver breakpoint.\n");
1333 /* If we were single-stepping, we definitely want to report the
1334 SIGTRAP. Although the single-step operation has completed,
1335 do not clear clear the stepping flag yet; we need to check it
1336 in wait_for_sigstop. */
1337 if (event_child
->stepping
)
1338 return lwpid_of (event_child
);
1340 /* A SIGTRAP that we can't explain. It may have been a breakpoint.
1341 Check if it is a breakpoint, and if so mark the process information
1342 accordingly. This will handle both the necessary fiddling with the
1343 PC on decr_pc_after_break targets and suppressing extra threads
1344 hitting a breakpoint if two hit it at once and then GDB removes it
1345 after the first is reported. Arguably it would be better to report
1346 multiple threads hitting breakpoints simultaneously, but the current
1347 remote protocol does not allow this. */
1348 if ((*the_low_target
.breakpoint_at
) (stop_pc
))
1350 event_child
->pending_is_breakpoint
= 1;
1351 event_child
->pending_stop_pc
= stop_pc
;
1354 return lwpid_of (event_child
);
1362 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1366 if (ptid_is_pid (ptid
))
1368 /* A request to wait for a specific tgid. This is not possible
1369 with waitpid, so instead, we wait for any child, and leave
1370 children we're not interested in right now with a pending
1371 status to report later. */
1372 wait_ptid
= minus_one_ptid
;
1381 event_pid
= linux_wait_for_event_1 (wait_ptid
, wstat
, options
);
1384 && ptid_is_pid (ptid
) && ptid_get_pid (ptid
) != event_pid
)
1386 struct lwp_info
*event_child
= find_lwp_pid (pid_to_ptid (event_pid
));
1388 if (! WIFSTOPPED (*wstat
))
1389 mark_lwp_dead (event_child
, *wstat
);
1392 event_child
->status_pending_p
= 1;
1393 event_child
->status_pending
= *wstat
;
1401 /* Wait for process, returns status. */
1404 linux_wait_1 (ptid_t ptid
,
1405 struct target_waitstatus
*ourstatus
, int target_options
)
1408 struct thread_info
*thread
= NULL
;
1409 struct lwp_info
*lwp
= NULL
;
1413 /* Translate generic target options into linux options. */
1415 if (target_options
& TARGET_WNOHANG
)
1419 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
1421 /* If we were only supposed to resume one thread, only wait for
1422 that thread - if it's still alive. If it died, however - which
1423 can happen if we're coming from the thread death case below -
1424 then we need to make sure we restart the other threads. We could
1425 pick a thread at random or restart all; restarting all is less
1428 && !ptid_equal (cont_thread
, null_ptid
)
1429 && !ptid_equal (cont_thread
, minus_one_ptid
))
1431 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
1434 /* No stepping, no signal - unless one is pending already, of course. */
1437 struct thread_resume resume_info
;
1438 resume_info
.thread
= minus_one_ptid
;
1439 resume_info
.kind
= resume_continue
;
1440 resume_info
.sig
= 0;
1441 linux_resume (&resume_info
, 1);
1447 pid
= linux_wait_for_event (ptid
, &w
, options
);
1448 if (pid
== 0) /* only if TARGET_WNOHANG */
1451 lwp
= get_thread_lwp (current_inferior
);
1453 /* If we are waiting for a particular child, and it exited,
1454 linux_wait_for_event will return its exit status. Similarly if
1455 the last child exited. If this is not the last child, however,
1456 do not report it as exited until there is a 'thread exited' response
1457 available in the remote protocol. Instead, just wait for another event.
1458 This should be safe, because if the thread crashed we will already
1459 have reported the termination signal to GDB; that should stop any
1460 in-progress stepping operations, etc.
1462 Report the exit status of the last thread to exit. This matches
1463 LinuxThreads' behavior. */
1465 if (last_thread_of_process_p (current_inferior
))
1467 if (WIFEXITED (w
) || WIFSIGNALED (w
))
1469 int pid
= pid_of (lwp
);
1470 struct process_info
*process
= find_process_pid (pid
);
1472 #ifdef USE_THREAD_DB
1473 thread_db_free (process
, 0);
1476 linux_remove_process (process
);
1478 current_inferior
= NULL
;
1482 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
1483 ourstatus
->value
.integer
= WEXITSTATUS (w
);
1486 fprintf (stderr
, "\nChild exited with retcode = %x \n", WEXITSTATUS (w
));
1490 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
1491 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
1494 fprintf (stderr
, "\nChild terminated with signal = %x \n", WTERMSIG (w
));
1498 return pid_to_ptid (pid
);
1503 if (!WIFSTOPPED (w
))
1507 /* In all-stop, stop all threads. Be careful to only do this if
1508 we're about to report an event to GDB. */
1512 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
1514 if (lwp
->suspended
&& WSTOPSIG (w
) == SIGSTOP
)
1516 /* A thread that has been requested to stop by GDB with vCont;t,
1517 and it stopped cleanly, so report as SIG0. The use of
1518 SIGSTOP is an implementation detail. */
1519 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
1521 else if (lwp
->suspended
&& WSTOPSIG (w
) != SIGSTOP
)
1523 /* A thread that has been requested to stop by GDB with vCont;t,
1524 but, it stopped for other reasons. Set stop_expected so the
1525 pending SIGSTOP is ignored and the LWP is resumed. */
1526 lwp
->stop_expected
= 1;
1527 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
1531 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
1535 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
1536 target_pid_to_str (lwp
->head
.id
),
1538 ourstatus
->value
.sig
);
1540 return lwp
->head
.id
;
1543 /* Get rid of any pending event in the pipe. */
1545 async_file_flush (void)
1551 ret
= read (linux_event_pipe
[0], &buf
, 1);
1552 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
1555 /* Put something in the pipe, so the event loop wakes up. */
1557 async_file_mark (void)
1561 async_file_flush ();
1564 ret
= write (linux_event_pipe
[1], "+", 1);
1565 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
1567 /* Ignore EAGAIN. If the pipe is full, the event loop will already
1568 be awakened anyway. */
1572 linux_wait (ptid_t ptid
,
1573 struct target_waitstatus
*ourstatus
, int target_options
)
1578 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
1580 /* Flush the async file first. */
1581 if (target_is_async_p ())
1582 async_file_flush ();
1584 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
1586 /* If at least one stop was reported, there may be more. A single
1587 SIGCHLD can signal more than one child stop. */
1588 if (target_is_async_p ()
1589 && (target_options
& TARGET_WNOHANG
) != 0
1590 && !ptid_equal (event_ptid
, null_ptid
))
1596 /* Send a signal to an LWP. */
1599 kill_lwp (unsigned long lwpid
, int signo
)
1601 /* Use tkill, if possible, in case we are using nptl threads. If tkill
1602 fails, then we are not using nptl threads and we should be using kill. */
1606 static int tkill_failed
;
1613 ret
= syscall (__NR_tkill
, lwpid
, signo
);
1614 if (errno
!= ENOSYS
)
1621 return kill (lwpid
, signo
);
1625 send_sigstop (struct inferior_list_entry
*entry
)
1627 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1633 pid
= lwpid_of (lwp
);
1635 /* If we already have a pending stop signal for this process, don't
1637 if (lwp
->stop_expected
)
1640 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
1642 /* We clear the stop_expected flag so that wait_for_sigstop
1643 will receive the SIGSTOP event (instead of silently resuming and
1644 waiting again). It'll be reset below. */
1645 lwp
->stop_expected
= 0;
1650 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
1652 kill_lwp (pid
, SIGSTOP
);
1656 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
1658 /* It's dead, really. */
1661 /* Store the exit status for later. */
1662 lwp
->status_pending_p
= 1;
1663 lwp
->status_pending
= wstat
;
1665 /* So that check_removed_breakpoint doesn't try to figure out if
1666 this is stopped at a breakpoint. */
1667 lwp
->pending_is_breakpoint
= 0;
1669 /* Prevent trying to stop it. */
1672 /* No further stops are expected from a dead lwp. */
1673 lwp
->stop_expected
= 0;
1677 wait_for_sigstop (struct inferior_list_entry
*entry
)
1679 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1680 struct thread_info
*saved_inferior
;
1688 saved_inferior
= current_inferior
;
1689 if (saved_inferior
!= NULL
)
1690 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
1692 saved_tid
= null_ptid
; /* avoid bogus unused warning */
1694 ptid
= lwp
->head
.id
;
1696 linux_wait_for_event (ptid
, &wstat
, __WALL
);
1698 /* If we stopped with a non-SIGSTOP signal, save it for later
1699 and record the pending SIGSTOP. If the process exited, just
1701 if (WIFSTOPPED (wstat
)
1702 && WSTOPSIG (wstat
) != SIGSTOP
)
1705 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
1706 lwpid_of (lwp
), wstat
);
1708 /* Do not leave a pending single-step finish to be reported to
1709 the client. The client will give us a new action for this
1710 thread, possibly a continue request --- otherwise, the client
1711 would consider this pending SIGTRAP reported later a spurious
1713 if (WSTOPSIG (wstat
) == SIGTRAP
1715 && !linux_stopped_by_watchpoint ())
1718 fprintf (stderr
, " single-step SIGTRAP ignored\n");
1722 lwp
->status_pending_p
= 1;
1723 lwp
->status_pending
= wstat
;
1725 lwp
->stop_expected
= 1;
1727 else if (!WIFSTOPPED (wstat
))
1730 fprintf (stderr
, "Process %ld exited while stopping LWPs\n",
1733 /* Leave this status pending for the next time we're able to
1734 report it. In the mean time, we'll report this lwp as dead
1735 to GDB, so GDB doesn't try to read registers and memory from
1737 mark_lwp_dead (lwp
, wstat
);
1740 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
1741 current_inferior
= saved_inferior
;
1745 fprintf (stderr
, "Previously current thread died.\n");
1749 /* We can't change the current inferior behind GDB's back,
1750 otherwise, a subsequent command may apply to the wrong
1752 current_inferior
= NULL
;
1756 /* Set a valid thread as current. */
1757 set_desired_inferior (0);
1763 stop_all_lwps (void)
1765 stopping_threads
= 1;
1766 for_each_inferior (&all_lwps
, send_sigstop
);
1767 for_each_inferior (&all_lwps
, wait_for_sigstop
);
1768 stopping_threads
= 0;
1771 /* Resume execution of the inferior process.
1772 If STEP is nonzero, single-step it.
1773 If SIGNAL is nonzero, give it that signal. */
1776 linux_resume_one_lwp (struct lwp_info
*lwp
,
1777 int step
, int signal
, siginfo_t
*info
)
1779 struct thread_info
*saved_inferior
;
1781 if (lwp
->stopped
== 0)
1784 /* If we have pending signals or status, and a new signal, enqueue the
1785 signal. Also enqueue the signal if we are waiting to reinsert a
1786 breakpoint; it will be picked up again below. */
1788 && (lwp
->status_pending_p
|| lwp
->pending_signals
!= NULL
1789 || lwp
->bp_reinsert
!= 0))
1791 struct pending_signals
*p_sig
;
1792 p_sig
= xmalloc (sizeof (*p_sig
));
1793 p_sig
->prev
= lwp
->pending_signals
;
1794 p_sig
->signal
= signal
;
1796 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1798 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
1799 lwp
->pending_signals
= p_sig
;
1802 if (lwp
->status_pending_p
&& !check_removed_breakpoint (lwp
))
1805 saved_inferior
= current_inferior
;
1806 current_inferior
= get_lwp_thread (lwp
);
1809 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
1810 lwpid_of (lwp
), step
? "step" : "continue", signal
,
1811 lwp
->stop_expected
? "expected" : "not expected");
1813 /* This bit needs some thinking about. If we get a signal that
1814 we must report while a single-step reinsert is still pending,
1815 we often end up resuming the thread. It might be better to
1816 (ew) allow a stack of pending events; then we could be sure that
1817 the reinsert happened right away and not lose any signals.
1819 Making this stack would also shrink the window in which breakpoints are
1820 uninserted (see comment in linux_wait_for_lwp) but not enough for
1821 complete correctness, so it won't solve that problem. It may be
1822 worthwhile just to solve this one, however. */
1823 if (lwp
->bp_reinsert
!= 0)
1826 fprintf (stderr
, " pending reinsert at %08lx", (long)lwp
->bp_reinsert
);
1828 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
1831 /* Postpone any pending signal. It was enqueued above. */
1835 check_removed_breakpoint (lwp
);
1837 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
1839 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
1840 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
1841 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
1844 /* If we have pending signals, consume one unless we are trying to reinsert
1846 if (lwp
->pending_signals
!= NULL
&& lwp
->bp_reinsert
== 0)
1848 struct pending_signals
**p_sig
;
1850 p_sig
= &lwp
->pending_signals
;
1851 while ((*p_sig
)->prev
!= NULL
)
1852 p_sig
= &(*p_sig
)->prev
;
1854 signal
= (*p_sig
)->signal
;
1855 if ((*p_sig
)->info
.si_signo
!= 0)
1856 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
1862 if (the_low_target
.prepare_to_resume
!= NULL
)
1863 the_low_target
.prepare_to_resume (lwp
);
1865 regcache_invalidate_one ((struct inferior_list_entry
*)
1866 get_lwp_thread (lwp
));
1869 lwp
->stepping
= step
;
1870 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0,
1871 /* Coerce to a uintptr_t first to avoid potential gcc warning
1872 of coercing an 8 byte integer to a 4 byte pointer. */
1873 (PTRACE_ARG4_TYPE
) (uintptr_t) signal
);
1875 current_inferior
= saved_inferior
;
1878 /* ESRCH from ptrace either means that the thread was already
1879 running (an error) or that it is gone (a race condition). If
1880 it's gone, we will get a notification the next time we wait,
1881 so we can ignore the error. We could differentiate these
1882 two, but it's tricky without waiting; the thread still exists
1883 as a zombie, so sending it signal 0 would succeed. So just
1888 perror_with_name ("ptrace");
1892 struct thread_resume_array
1894 struct thread_resume
*resume
;
1898 /* This function is called once per thread. We look up the thread
1899 in RESUME_PTR, and mark the thread with a pointer to the appropriate
1902 This algorithm is O(threads * resume elements), but resume elements
1903 is small (and will remain small at least until GDB supports thread
1906 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
1908 struct lwp_info
*lwp
;
1909 struct thread_info
*thread
;
1911 struct thread_resume_array
*r
;
1913 thread
= (struct thread_info
*) entry
;
1914 lwp
= get_thread_lwp (thread
);
1917 for (ndx
= 0; ndx
< r
->n
; ndx
++)
1919 ptid_t ptid
= r
->resume
[ndx
].thread
;
1920 if (ptid_equal (ptid
, minus_one_ptid
)
1921 || ptid_equal (ptid
, entry
->id
)
1922 || (ptid_is_pid (ptid
)
1923 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
1924 || (ptid_get_lwp (ptid
) == -1
1925 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
1927 lwp
->resume
= &r
->resume
[ndx
];
1932 /* No resume action for this thread. */
1939 /* Set *FLAG_P if this lwp has an interesting status pending. */
1941 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
1943 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1945 /* LWPs which will not be resumed are not interesting, because
1946 we might not wait for them next time through linux_wait. */
1947 if (lwp
->resume
== NULL
)
1950 /* If this thread has a removed breakpoint, we won't have any
1951 events to report later, so check now. check_removed_breakpoint
1952 may clear status_pending_p. We avoid calling check_removed_breakpoint
1953 for any thread that we are not otherwise going to resume - this
1954 lets us preserve stopped status when two threads hit a breakpoint.
1955 GDB removes the breakpoint to single-step a particular thread
1956 past it, then re-inserts it and resumes all threads. We want
1957 to report the second thread without resuming it in the interim. */
1958 if (lwp
->status_pending_p
)
1959 check_removed_breakpoint (lwp
);
1961 if (lwp
->status_pending_p
)
1962 * (int *) flag_p
= 1;
1967 /* This function is called once per thread. We check the thread's resume
1968 request, which will tell us whether to resume, step, or leave the thread
1969 stopped; and what signal, if any, it should be sent.
1971 For threads which we aren't explicitly told otherwise, we preserve
1972 the stepping flag; this is used for stepping over gdbserver-placed
1975 If pending_flags was set in any thread, we queue any needed
1976 signals, since we won't actually resume. We already have a pending
1977 event to report, so we don't need to preserve any step requests;
1978 they should be re-issued if necessary. */
1981 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
1983 struct lwp_info
*lwp
;
1984 struct thread_info
*thread
;
1986 int pending_flag
= * (int *) arg
;
1988 thread
= (struct thread_info
*) entry
;
1989 lwp
= get_thread_lwp (thread
);
1991 if (lwp
->resume
== NULL
)
1994 if (lwp
->resume
->kind
== resume_stop
)
1997 fprintf (stderr
, "suspending LWP %ld\n", lwpid_of (lwp
));
2002 fprintf (stderr
, "running -> suspending LWP %ld\n", lwpid_of (lwp
));
2005 send_sigstop (&lwp
->head
);
2012 fprintf (stderr
, "already stopped/suspended LWP %ld\n",
2015 fprintf (stderr
, "already stopped/not suspended LWP %ld\n",
2019 /* Make sure we leave the LWP suspended, so we don't try to
2020 resume it without GDB telling us to. FIXME: The LWP may
2021 have been stopped in an internal event that was not meant
2022 to be notified back to GDB (e.g., gdbserver breakpoint),
2023 so we should be reporting a stop event in that case
2028 /* For stop requests, we're done. */
2035 /* If this thread which is about to be resumed has a pending status,
2036 then don't resume any threads - we can just report the pending
2037 status. Make sure to queue any signals that would otherwise be
2038 sent. In all-stop mode, we do this decision based on if *any*
2039 thread has a pending status. */
2041 resume_status_pending_p (&lwp
->head
, &pending_flag
);
2046 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
2048 if (ptid_equal (lwp
->resume
->thread
, minus_one_ptid
)
2050 && lwp
->pending_is_breakpoint
)
2053 step
= (lwp
->resume
->kind
== resume_step
);
2055 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
2060 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
2062 /* If we have a new signal, enqueue the signal. */
2063 if (lwp
->resume
->sig
!= 0)
2065 struct pending_signals
*p_sig
;
2066 p_sig
= xmalloc (sizeof (*p_sig
));
2067 p_sig
->prev
= lwp
->pending_signals
;
2068 p_sig
->signal
= lwp
->resume
->sig
;
2069 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
2071 /* If this is the same signal we were previously stopped by,
2072 make sure to queue its siginfo. We can ignore the return
2073 value of ptrace; if it fails, we'll skip
2074 PTRACE_SETSIGINFO. */
2075 if (WIFSTOPPED (lwp
->last_status
)
2076 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
2077 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
2079 lwp
->pending_signals
= p_sig
;
2088 linux_resume (struct thread_resume
*resume_info
, size_t n
)
2091 struct thread_resume_array array
= { resume_info
, n
};
2093 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
2095 /* If there is a thread which would otherwise be resumed, which
2096 has a pending status, then don't resume any threads - we can just
2097 report the pending status. Make sure to queue any signals
2098 that would otherwise be sent. In non-stop mode, we'll apply this
2099 logic to each thread individually. */
2102 find_inferior (&all_lwps
, resume_status_pending_p
, &pending_flag
);
2107 fprintf (stderr
, "Not resuming, pending status\n");
2109 fprintf (stderr
, "Resuming, no pending status\n");
2112 find_inferior (&all_threads
, linux_resume_one_thread
, &pending_flag
);
2115 #ifdef HAVE_LINUX_USRREGS
2118 register_addr (int regnum
)
2122 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
2123 error ("Invalid register number %d.", regnum
);
2125 addr
= the_low_target
.regmap
[regnum
];
2130 /* Fetch one register. */
2132 fetch_register (struct regcache
*regcache
, int regno
)
2139 if (regno
>= the_low_target
.num_regs
)
2141 if ((*the_low_target
.cannot_fetch_register
) (regno
))
2144 regaddr
= register_addr (regno
);
2148 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2149 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2150 & - sizeof (PTRACE_XFER_TYPE
));
2151 buf
= alloca (size
);
2152 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
2155 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
2156 ptrace (PTRACE_PEEKUSER
, pid
,
2157 /* Coerce to a uintptr_t first to avoid potential gcc warning
2158 of coercing an 8 byte integer to a 4 byte pointer. */
2159 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
, 0);
2160 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
2163 /* Warning, not error, in case we are attached; sometimes the
2164 kernel doesn't let us at the registers. */
2165 char *err
= strerror (errno
);
2166 char *msg
= alloca (strlen (err
) + 128);
2167 sprintf (msg
, "reading register %d: %s", regno
, err
);
2173 if (the_low_target
.supply_ptrace_register
)
2174 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
2176 supply_register (regcache
, regno
, buf
);
2181 /* Fetch all registers, or just one, from the child process. */
2183 usr_fetch_inferior_registers (struct regcache
*regcache
, int regno
)
2186 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
2187 fetch_register (regcache
, regno
);
2189 fetch_register (regcache
, regno
);
2192 /* Store our register values back into the inferior.
2193 If REGNO is -1, do this for all registers.
2194 Otherwise, REGNO specifies which register (so we can save time). */
2196 usr_store_inferior_registers (struct regcache
*regcache
, int regno
)
2205 if (regno
>= the_low_target
.num_regs
)
2208 if ((*the_low_target
.cannot_store_register
) (regno
) == 1)
2211 regaddr
= register_addr (regno
);
2215 size
= (register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2216 & - sizeof (PTRACE_XFER_TYPE
);
2217 buf
= alloca (size
);
2218 memset (buf
, 0, size
);
2220 if (the_low_target
.collect_ptrace_register
)
2221 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
2223 collect_register (regcache
, regno
, buf
);
2225 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2226 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
2229 ptrace (PTRACE_POKEUSER
, pid
,
2230 /* Coerce to a uintptr_t first to avoid potential gcc warning
2231 about coercing an 8 byte integer to a 4 byte pointer. */
2232 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
,
2233 (PTRACE_ARG4_TYPE
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
2236 /* At this point, ESRCH should mean the process is
2237 already gone, in which case we simply ignore attempts
2238 to change its registers. See also the related
2239 comment in linux_resume_one_lwp. */
2243 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
2245 char *err
= strerror (errno
);
2246 char *msg
= alloca (strlen (err
) + 128);
2247 sprintf (msg
, "writing register %d: %s",
2253 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
2257 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
2258 usr_store_inferior_registers (regcache
, regno
);
2260 #endif /* HAVE_LINUX_USRREGS */
2264 #ifdef HAVE_LINUX_REGSETS
2267 regsets_fetch_inferior_registers (struct regcache
*regcache
)
2269 struct regset_info
*regset
;
2270 int saw_general_regs
= 0;
2273 regset
= target_regsets
;
2275 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2276 while (regset
->size
>= 0)
2281 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
2287 buf
= xmalloc (regset
->size
);
2289 res
= ptrace (regset
->get_request
, pid
, 0, buf
);
2291 res
= ptrace (regset
->get_request
, pid
, buf
, 0);
2297 /* If we get EIO on a regset, do not try it again for
2299 disabled_regsets
[regset
- target_regsets
] = 1;
2306 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
2311 else if (regset
->type
== GENERAL_REGS
)
2312 saw_general_regs
= 1;
2313 regset
->store_function (regcache
, buf
);
2317 if (saw_general_regs
)
2324 regsets_store_inferior_registers (struct regcache
*regcache
)
2326 struct regset_info
*regset
;
2327 int saw_general_regs
= 0;
2330 regset
= target_regsets
;
2332 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2333 while (regset
->size
>= 0)
2338 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
2344 buf
= xmalloc (regset
->size
);
2346 /* First fill the buffer with the current register set contents,
2347 in case there are any items in the kernel's regset that are
2348 not in gdbserver's regcache. */
2350 res
= ptrace (regset
->get_request
, pid
, 0, buf
);
2352 res
= ptrace (regset
->get_request
, pid
, buf
, 0);
2357 /* Then overlay our cached registers on that. */
2358 regset
->fill_function (regcache
, buf
);
2360 /* Only now do we write the register set. */
2362 res
= ptrace (regset
->set_request
, pid
, 0, buf
);
2364 res
= ptrace (regset
->set_request
, pid
, buf
, 0);
2372 /* If we get EIO on a regset, do not try it again for
2374 disabled_regsets
[regset
- target_regsets
] = 1;
2378 else if (errno
== ESRCH
)
2380 /* At this point, ESRCH should mean the process is
2381 already gone, in which case we simply ignore attempts
2382 to change its registers. See also the related
2383 comment in linux_resume_one_lwp. */
2389 perror ("Warning: ptrace(regsets_store_inferior_registers)");
2392 else if (regset
->type
== GENERAL_REGS
)
2393 saw_general_regs
= 1;
2397 if (saw_general_regs
)
2404 #endif /* HAVE_LINUX_REGSETS */
2408 linux_fetch_registers (struct regcache
*regcache
, int regno
)
2410 #ifdef HAVE_LINUX_REGSETS
2411 if (regsets_fetch_inferior_registers (regcache
) == 0)
2414 #ifdef HAVE_LINUX_USRREGS
2415 usr_fetch_inferior_registers (regcache
, regno
);
2420 linux_store_registers (struct regcache
*regcache
, int regno
)
2422 #ifdef HAVE_LINUX_REGSETS
2423 if (regsets_store_inferior_registers (regcache
) == 0)
2426 #ifdef HAVE_LINUX_USRREGS
2427 usr_store_inferior_registers (regcache
, regno
);
2432 /* Copy LEN bytes from inferior's memory starting at MEMADDR
2433 to debugger memory starting at MYADDR. */
2436 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
2439 /* Round starting address down to longword boundary. */
2440 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
2441 /* Round ending address up; get number of longwords that makes. */
2443 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2444 / sizeof (PTRACE_XFER_TYPE
);
2445 /* Allocate buffer of that many longwords. */
2446 register PTRACE_XFER_TYPE
*buffer
2447 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
2450 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2452 /* Try using /proc. Don't bother for one word. */
2453 if (len
>= 3 * sizeof (long))
2455 /* We could keep this file open and cache it - possibly one per
2456 thread. That requires some juggling, but is even faster. */
2457 sprintf (filename
, "/proc/%d/mem", pid
);
2458 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
2462 /* If pread64 is available, use it. It's faster if the kernel
2463 supports it (only one syscall), and it's 64-bit safe even on
2464 32-bit platforms (for instance, SPARC debugging a SPARC64
2467 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
2469 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, myaddr
, len
) != len
)
2481 /* Read all the longwords */
2482 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
2485 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
2486 about coercing an 8 byte integer to a 4 byte pointer. */
2487 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
2488 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
2493 /* Copy appropriate bytes out of the buffer. */
2495 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
2501 /* Copy LEN bytes of data from debugger memory at MYADDR
2502 to inferior's memory at MEMADDR.
2503 On failure (cannot write the inferior)
2504 returns the value of errno. */
2507 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
2510 /* Round starting address down to longword boundary. */
2511 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
2512 /* Round ending address up; get number of longwords that makes. */
2514 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1) / sizeof (PTRACE_XFER_TYPE
);
2515 /* Allocate buffer of that many longwords. */
2516 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
2517 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2521 /* Dump up to four bytes. */
2522 unsigned int val
= * (unsigned int *) myaddr
;
2528 val
= val
& 0xffffff;
2529 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
2530 val
, (long)memaddr
);
2533 /* Fill start and end extra bytes of buffer with existing memory data. */
2535 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
2536 about coercing an 8 byte integer to a 4 byte pointer. */
2537 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
2538 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
2543 = ptrace (PTRACE_PEEKTEXT
, pid
,
2544 /* Coerce to a uintptr_t first to avoid potential gcc warning
2545 about coercing an 8 byte integer to a 4 byte pointer. */
2546 (PTRACE_ARG3_TYPE
) (uintptr_t) (addr
+ (count
- 1)
2547 * sizeof (PTRACE_XFER_TYPE
)),
2551 /* Copy data to be written over corresponding part of buffer */
2553 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)), myaddr
, len
);
2555 /* Write the entire buffer. */
2557 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
2560 ptrace (PTRACE_POKETEXT
, pid
,
2561 /* Coerce to a uintptr_t first to avoid potential gcc warning
2562 about coercing an 8 byte integer to a 4 byte pointer. */
2563 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
2564 (PTRACE_ARG4_TYPE
) buffer
[i
]);
2572 static int linux_supports_tracefork_flag
;
2574 /* Helper functions for linux_test_for_tracefork, called via clone (). */
2577 linux_tracefork_grandchild (void *arg
)
2582 #define STACK_SIZE 4096
2585 linux_tracefork_child (void *arg
)
2587 ptrace (PTRACE_TRACEME
, 0, 0, 0);
2588 kill (getpid (), SIGSTOP
);
2590 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
2591 CLONE_VM
| SIGCHLD
, NULL
);
2593 clone (linux_tracefork_grandchild
, arg
+ STACK_SIZE
,
2594 CLONE_VM
| SIGCHLD
, NULL
);
2599 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
2600 sure that we can enable the option, and that it had the desired
2604 linux_test_for_tracefork (void)
2606 int child_pid
, ret
, status
;
2608 char *stack
= xmalloc (STACK_SIZE
* 4);
2610 linux_supports_tracefork_flag
= 0;
2612 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
2614 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
2615 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
2617 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
2618 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
2620 if (child_pid
== -1)
2621 perror_with_name ("clone");
2623 ret
= my_waitpid (child_pid
, &status
, 0);
2625 perror_with_name ("waitpid");
2626 else if (ret
!= child_pid
)
2627 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
2628 if (! WIFSTOPPED (status
))
2629 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
2631 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
2632 (PTRACE_ARG4_TYPE
) PTRACE_O_TRACEFORK
);
2635 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
2638 warning ("linux_test_for_tracefork: failed to kill child");
2642 ret
= my_waitpid (child_pid
, &status
, 0);
2643 if (ret
!= child_pid
)
2644 warning ("linux_test_for_tracefork: failed to wait for killed child");
2645 else if (!WIFSIGNALED (status
))
2646 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
2647 "killed child", status
);
2652 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
2654 warning ("linux_test_for_tracefork: failed to resume child");
2656 ret
= my_waitpid (child_pid
, &status
, 0);
2658 if (ret
== child_pid
&& WIFSTOPPED (status
)
2659 && status
>> 16 == PTRACE_EVENT_FORK
)
2662 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
2663 if (ret
== 0 && second_pid
!= 0)
2667 linux_supports_tracefork_flag
= 1;
2668 my_waitpid (second_pid
, &second_status
, 0);
2669 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
2671 warning ("linux_test_for_tracefork: failed to kill second child");
2672 my_waitpid (second_pid
, &status
, 0);
2676 warning ("linux_test_for_tracefork: unexpected result from waitpid "
2677 "(%d, status 0x%x)", ret
, status
);
2681 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
2683 warning ("linux_test_for_tracefork: failed to kill child");
2684 my_waitpid (child_pid
, &status
, 0);
2686 while (WIFSTOPPED (status
));
2693 linux_look_up_symbols (void)
2695 #ifdef USE_THREAD_DB
2696 struct process_info
*proc
= current_process ();
2698 if (proc
->private->thread_db
!= NULL
)
2701 thread_db_init (!linux_supports_tracefork_flag
);
2706 linux_request_interrupt (void)
2708 extern unsigned long signal_pid
;
2710 if (!ptid_equal (cont_thread
, null_ptid
)
2711 && !ptid_equal (cont_thread
, minus_one_ptid
))
2713 struct lwp_info
*lwp
;
2716 lwp
= get_thread_lwp (current_inferior
);
2717 lwpid
= lwpid_of (lwp
);
2718 kill_lwp (lwpid
, SIGINT
);
2721 kill_lwp (signal_pid
, SIGINT
);
2724 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
2725 to debugger memory starting at MYADDR. */
2728 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
2730 char filename
[PATH_MAX
];
2732 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2734 snprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
2736 fd
= open (filename
, O_RDONLY
);
2740 if (offset
!= (CORE_ADDR
) 0
2741 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
2744 n
= read (fd
, myaddr
, len
);
2751 /* These breakpoint and watchpoint related wrapper functions simply
2752 pass on the function call if the target has registered a
2753 corresponding function. */
2756 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
2758 if (the_low_target
.insert_point
!= NULL
)
2759 return the_low_target
.insert_point (type
, addr
, len
);
2761 /* Unsupported (see target.h). */
2766 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
2768 if (the_low_target
.remove_point
!= NULL
)
2769 return the_low_target
.remove_point (type
, addr
, len
);
2771 /* Unsupported (see target.h). */
2776 linux_stopped_by_watchpoint (void)
2778 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2779 return the_low_target
.stopped_by_watchpoint ();
2785 linux_stopped_data_address (void)
2787 if (the_low_target
.stopped_data_address
!= NULL
)
2788 return the_low_target
.stopped_data_address ();
2793 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
2794 #if defined(__mcoldfire__)
2795 /* These should really be defined in the kernel's ptrace.h header. */
2796 #define PT_TEXT_ADDR 49*4
2797 #define PT_DATA_ADDR 50*4
2798 #define PT_TEXT_END_ADDR 51*4
2801 /* Under uClinux, programs are loaded at non-zero offsets, which we need
2802 to tell gdb about. */
2805 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
2807 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
2808 unsigned long text
, text_end
, data
;
2809 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2813 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
2814 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
2815 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
2819 /* Both text and data offsets produced at compile-time (and so
2820 used by gdb) are relative to the beginning of the program,
2821 with the data segment immediately following the text segment.
2822 However, the actual runtime layout in memory may put the data
2823 somewhere else, so when we send gdb a data base-address, we
2824 use the real data base address and subtract the compile-time
2825 data base-address from it (which is just the length of the
2826 text segment). BSS immediately follows data in both
2829 *data_p
= data
- (text_end
- text
);
2839 compare_ints (const void *xa
, const void *xb
)
2841 int a
= *(const int *)xa
;
2842 int b
= *(const int *)xb
;
2848 unique (int *b
, int *e
)
2857 /* Given PID, iterates over all threads in that process.
2859 Information about each thread, in a format suitable for qXfer:osdata:thread
2860 is printed to BUFFER, if it's not NULL. BUFFER is assumed to be already
2861 initialized, and the caller is responsible for finishing and appending '\0'
2864 The list of cores that threads are running on is assigned to *CORES, if it
2865 is not NULL. If no cores are found, *CORES will be set to NULL. Caller
2866 should free *CORES. */
2869 list_threads (int pid
, struct buffer
*buffer
, char **cores
)
2873 int *core_numbers
= xmalloc (sizeof (int) * allocated
);
2877 struct stat statbuf
;
2879 sprintf (pathname
, "/proc/%d/task", pid
);
2880 if (stat (pathname
, &statbuf
) == 0 && S_ISDIR (statbuf
.st_mode
))
2882 dir
= opendir (pathname
);
2885 free (core_numbers
);
2889 while ((dp
= readdir (dir
)) != NULL
)
2891 unsigned long lwp
= strtoul (dp
->d_name
, NULL
, 10);
2895 unsigned core
= linux_core_of_thread (ptid_build (pid
, lwp
, 0));
2899 char s
[sizeof ("4294967295")];
2900 sprintf (s
, "%u", core
);
2902 if (count
== allocated
)
2905 core_numbers
= realloc (core_numbers
,
2906 sizeof (int) * allocated
);
2908 core_numbers
[count
++] = core
;
2910 buffer_xml_printf (buffer
,
2912 "<column name=\"pid\">%d</column>"
2913 "<column name=\"tid\">%s</column>"
2914 "<column name=\"core\">%s</column>"
2915 "</item>", pid
, dp
->d_name
, s
);
2920 buffer_xml_printf (buffer
,
2922 "<column name=\"pid\">%d</column>"
2923 "<column name=\"tid\">%s</column>"
2924 "</item>", pid
, dp
->d_name
);
2935 struct buffer buffer2
;
2938 qsort (core_numbers
, count
, sizeof (int), compare_ints
);
2940 /* Remove duplicates. */
2942 e
= unique (b
, core_numbers
+ count
);
2944 buffer_init (&buffer2
);
2946 for (b
= core_numbers
; b
!= e
; ++b
)
2948 char number
[sizeof ("4294967295")];
2949 sprintf (number
, "%u", *b
);
2950 buffer_xml_printf (&buffer2
, "%s%s",
2951 (b
== core_numbers
) ? "" : ",", number
);
2953 buffer_grow_str0 (&buffer2
, "");
2955 *cores
= buffer_finish (&buffer2
);
2958 free (core_numbers
);
2962 show_process (int pid
, const char *username
, struct buffer
*buffer
)
2966 char cmd
[MAXPATHLEN
+ 1];
2968 sprintf (pathname
, "/proc/%d/cmdline", pid
);
2970 if ((f
= fopen (pathname
, "r")) != NULL
)
2972 size_t len
= fread (cmd
, 1, sizeof (cmd
) - 1, f
);
2977 for (i
= 0; i
< len
; i
++)
2982 buffer_xml_printf (buffer
,
2984 "<column name=\"pid\">%d</column>"
2985 "<column name=\"user\">%s</column>"
2986 "<column name=\"command\">%s</column>",
2991 /* This only collects core numbers, and does not print threads. */
2992 list_threads (pid
, NULL
, &cores
);
2996 buffer_xml_printf (buffer
,
2997 "<column name=\"cores\">%s</column>", cores
);
3001 buffer_xml_printf (buffer
, "</item>");
3008 linux_qxfer_osdata (const char *annex
,
3009 unsigned char *readbuf
, unsigned const char *writebuf
,
3010 CORE_ADDR offset
, int len
)
3012 /* We make the process list snapshot when the object starts to be
3014 static const char *buf
;
3015 static long len_avail
= -1;
3016 static struct buffer buffer
;
3022 if (strcmp (annex
, "processes") == 0)
3024 else if (strcmp (annex
, "threads") == 0)
3029 if (!readbuf
|| writebuf
)
3034 if (len_avail
!= -1 && len_avail
!= 0)
3035 buffer_free (&buffer
);
3038 buffer_init (&buffer
);
3040 buffer_grow_str (&buffer
, "<osdata type=\"processes\">");
3042 buffer_grow_str (&buffer
, "<osdata type=\"threads\">");
3044 dirp
= opendir ("/proc");
3048 while ((dp
= readdir (dirp
)) != NULL
)
3050 struct stat statbuf
;
3051 char procentry
[sizeof ("/proc/4294967295")];
3053 if (!isdigit (dp
->d_name
[0])
3054 || strlen (dp
->d_name
) > sizeof ("4294967295") - 1)
3057 sprintf (procentry
, "/proc/%s", dp
->d_name
);
3058 if (stat (procentry
, &statbuf
) == 0
3059 && S_ISDIR (statbuf
.st_mode
))
3061 int pid
= (int) strtoul (dp
->d_name
, NULL
, 10);
3065 struct passwd
*entry
= getpwuid (statbuf
.st_uid
);
3066 show_process (pid
, entry
? entry
->pw_name
: "?", &buffer
);
3070 list_threads (pid
, &buffer
, NULL
);
3077 buffer_grow_str0 (&buffer
, "</osdata>\n");
3078 buf
= buffer_finish (&buffer
);
3079 len_avail
= strlen (buf
);
3082 if (offset
>= len_avail
)
3084 /* Done. Get rid of the data. */
3085 buffer_free (&buffer
);
3091 if (len
> len_avail
- offset
)
3092 len
= len_avail
- offset
;
3093 memcpy (readbuf
, buf
+ offset
, len
);
3098 /* Convert a native/host siginfo object, into/from the siginfo in the
3099 layout of the inferiors' architecture. */
3102 siginfo_fixup (struct siginfo
*siginfo
, void *inf_siginfo
, int direction
)
3106 if (the_low_target
.siginfo_fixup
!= NULL
)
3107 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
3109 /* If there was no callback, or the callback didn't do anything,
3110 then just do a straight memcpy. */
3114 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
3116 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
3121 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
3122 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
3125 struct siginfo siginfo
;
3126 char inf_siginfo
[sizeof (struct siginfo
)];
3128 if (current_inferior
== NULL
)
3131 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3134 fprintf (stderr
, "%s siginfo for lwp %d.\n",
3135 readbuf
!= NULL
? "Reading" : "Writing",
3138 if (offset
> sizeof (siginfo
))
3141 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
3144 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
3145 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
3146 inferior with a 64-bit GDBSERVER should look the same as debugging it
3147 with a 32-bit GDBSERVER, we need to convert it. */
3148 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
3150 if (offset
+ len
> sizeof (siginfo
))
3151 len
= sizeof (siginfo
) - offset
;
3153 if (readbuf
!= NULL
)
3154 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
3157 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
3159 /* Convert back to ptrace layout before flushing it out. */
3160 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
3162 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
3169 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
3170 so we notice when children change state; as the handler for the
3171 sigsuspend in my_waitpid. */
3174 sigchld_handler (int signo
)
3176 int old_errno
= errno
;
3179 /* fprintf is not async-signal-safe, so call write directly. */
3180 write (2, "sigchld_handler\n", sizeof ("sigchld_handler\n") - 1);
3182 if (target_is_async_p ())
3183 async_file_mark (); /* trigger a linux_wait */
3189 linux_supports_non_stop (void)
3195 linux_async (int enable
)
3197 int previous
= (linux_event_pipe
[0] != -1);
3199 if (previous
!= enable
)
3202 sigemptyset (&mask
);
3203 sigaddset (&mask
, SIGCHLD
);
3205 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
3209 if (pipe (linux_event_pipe
) == -1)
3210 fatal ("creating event pipe failed.");
3212 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
3213 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
3215 /* Register the event loop handler. */
3216 add_file_handler (linux_event_pipe
[0],
3217 handle_target_event
, NULL
);
3219 /* Always trigger a linux_wait. */
3224 delete_file_handler (linux_event_pipe
[0]);
3226 close (linux_event_pipe
[0]);
3227 close (linux_event_pipe
[1]);
3228 linux_event_pipe
[0] = -1;
3229 linux_event_pipe
[1] = -1;
3232 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
3239 linux_start_non_stop (int nonstop
)
3241 /* Register or unregister from event-loop accordingly. */
3242 linux_async (nonstop
);
3247 linux_supports_multi_process (void)
3253 /* Enumerate spufs IDs for process PID. */
3255 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
3261 struct dirent
*entry
;
3263 sprintf (path
, "/proc/%ld/fd", pid
);
3264 dir
= opendir (path
);
3269 while ((entry
= readdir (dir
)) != NULL
)
3275 fd
= atoi (entry
->d_name
);
3279 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
3280 if (stat (path
, &st
) != 0)
3282 if (!S_ISDIR (st
.st_mode
))
3285 if (statfs (path
, &stfs
) != 0)
3287 if (stfs
.f_type
!= SPUFS_MAGIC
)
3290 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
3292 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
3302 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
3303 object type, using the /proc file system. */
3305 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
3306 unsigned const char *writebuf
,
3307 CORE_ADDR offset
, int len
)
3309 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
3314 if (!writebuf
&& !readbuf
)
3322 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
3325 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
3326 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
3331 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
3338 ret
= write (fd
, writebuf
, (size_t) len
);
3340 ret
= read (fd
, readbuf
, (size_t) len
);
3347 linux_core_of_thread (ptid_t ptid
)
3349 char filename
[sizeof ("/proc//task//stat")
3350 + 2 * 20 /* decimal digits for 2 numbers, max 2^64 bit each */
3353 char *content
= NULL
;
3356 int content_read
= 0;
3360 sprintf (filename
, "/proc/%d/task/%ld/stat",
3361 ptid_get_pid (ptid
), ptid_get_lwp (ptid
));
3362 f
= fopen (filename
, "r");
3369 content
= realloc (content
, content_read
+ 1024);
3370 n
= fread (content
+ content_read
, 1, 1024, f
);
3374 content
[content_read
] = '\0';
3379 p
= strchr (content
, '(');
3380 p
= strchr (p
, ')') + 2; /* skip ")" and a whitespace. */
3382 p
= strtok_r (p
, " ", &ts
);
3383 for (i
= 0; i
!= 36; ++i
)
3384 p
= strtok_r (NULL
, " ", &ts
);
3386 if (sscanf (p
, "%d", &core
) == 0)
3395 static struct target_ops linux_target_ops
= {
3396 linux_create_inferior
,
3404 linux_fetch_registers
,
3405 linux_store_registers
,
3408 linux_look_up_symbols
,
3409 linux_request_interrupt
,
3413 linux_stopped_by_watchpoint
,
3414 linux_stopped_data_address
,
3415 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
3420 #ifdef USE_THREAD_DB
3421 thread_db_get_tls_address
,
3426 hostio_last_error_from_errno
,
3429 linux_supports_non_stop
,
3431 linux_start_non_stop
,
3432 linux_supports_multi_process
,
3433 #ifdef USE_THREAD_DB
3434 thread_db_handle_monitor_command
,
3438 linux_core_of_thread
3442 linux_init_signals ()
3444 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
3445 to find what the cancel signal actually is. */
3446 #ifdef __SIGRTMIN /* Bionic doesn't use SIGRTMIN the way glibc does. */
3447 signal (__SIGRTMIN
+1, SIG_IGN
);
3452 initialize_low (void)
3454 struct sigaction sigchld_action
;
3455 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
3456 set_target_ops (&linux_target_ops
);
3457 set_breakpoint_data (the_low_target
.breakpoint
,
3458 the_low_target
.breakpoint_len
);
3459 linux_init_signals ();
3460 linux_test_for_tracefork ();
3461 #ifdef HAVE_LINUX_REGSETS
3462 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
3464 disabled_regsets
= xmalloc (num_regsets
);
3467 sigchld_action
.sa_handler
= sigchld_handler
;
3468 sigemptyset (&sigchld_action
.sa_mask
);
3469 sigchld_action
.sa_flags
= SA_RESTART
;
3470 sigaction (SIGCHLD
, &sigchld_action
, NULL
);