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
);
143 static int linux_core_of_thread (ptid_t ptid
);
145 struct pending_signals
149 struct pending_signals
*prev
;
152 #define PTRACE_ARG3_TYPE long
153 #define PTRACE_XFER_TYPE long
155 #ifdef HAVE_LINUX_REGSETS
156 static char *disabled_regsets
;
157 static int num_regsets
;
160 /* The read/write ends of the pipe registered as waitable file in the
162 static int linux_event_pipe
[2] = { -1, -1 };
164 /* True if we're currently in async mode. */
165 #define target_is_async_p() (linux_event_pipe[0] != -1)
167 static void send_sigstop (struct inferior_list_entry
*entry
);
168 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
170 /* Accepts an integer PID; Returns a string representing a file that
171 can be opened to get info for the child process.
172 Space for the result is malloc'd, caller must free. */
175 linux_child_pid_to_exec_file (int pid
)
179 name1
= xmalloc (MAXPATHLEN
);
180 name2
= xmalloc (MAXPATHLEN
);
181 memset (name2
, 0, MAXPATHLEN
);
183 sprintf (name1
, "/proc/%d/exe", pid
);
184 if (readlink (name1
, name2
, MAXPATHLEN
) > 0)
196 /* Return non-zero if HEADER is a 64-bit ELF file. */
199 elf_64_header_p (const Elf64_Ehdr
*header
)
201 return (header
->e_ident
[EI_MAG0
] == ELFMAG0
202 && header
->e_ident
[EI_MAG1
] == ELFMAG1
203 && header
->e_ident
[EI_MAG2
] == ELFMAG2
204 && header
->e_ident
[EI_MAG3
] == ELFMAG3
205 && header
->e_ident
[EI_CLASS
] == ELFCLASS64
);
208 /* Return non-zero if FILE is a 64-bit ELF file,
209 zero if the file is not a 64-bit ELF file,
210 and -1 if the file is not accessible or doesn't exist. */
213 elf_64_file_p (const char *file
)
218 fd
= open (file
, O_RDONLY
);
222 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
229 return elf_64_header_p (&header
);
233 delete_lwp (struct lwp_info
*lwp
)
235 remove_thread (get_lwp_thread (lwp
));
236 remove_inferior (&all_lwps
, &lwp
->head
);
237 free (lwp
->arch_private
);
241 /* Add a process to the common process list, and set its private
244 static struct process_info
*
245 linux_add_process (int pid
, int attached
)
247 struct process_info
*proc
;
249 /* Is this the first process? If so, then set the arch. */
250 if (all_processes
.head
== NULL
)
253 proc
= add_process (pid
, attached
);
254 proc
->private = xcalloc (1, sizeof (*proc
->private));
256 if (the_low_target
.new_process
!= NULL
)
257 proc
->private->arch_private
= the_low_target
.new_process ();
262 /* Remove a process from the common process list,
263 also freeing all private data. */
266 linux_remove_process (struct process_info
*process
)
268 struct process_info_private
*priv
= process
->private;
270 free (priv
->arch_private
);
272 remove_process (process
);
275 /* Wrapper function for waitpid which handles EINTR, and emulates
276 __WALL for systems where that is not available. */
279 my_waitpid (int pid
, int *status
, int flags
)
284 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
288 sigset_t block_mask
, org_mask
, wake_mask
;
291 wnohang
= (flags
& WNOHANG
) != 0;
292 flags
&= ~(__WALL
| __WCLONE
);
295 /* Block all signals while here. This avoids knowing about
296 LinuxThread's signals. */
297 sigfillset (&block_mask
);
298 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
300 /* ... except during the sigsuspend below. */
301 sigemptyset (&wake_mask
);
305 /* Since all signals are blocked, there's no need to check
307 ret
= waitpid (pid
, status
, flags
);
310 if (ret
== -1 && out_errno
!= ECHILD
)
315 if (flags
& __WCLONE
)
317 /* We've tried both flavors now. If WNOHANG is set,
318 there's nothing else to do, just bail out. */
323 fprintf (stderr
, "blocking\n");
325 /* Block waiting for signals. */
326 sigsuspend (&wake_mask
);
332 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
337 ret
= waitpid (pid
, status
, flags
);
338 while (ret
== -1 && errno
== EINTR
);
343 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
344 pid
, flags
, status
? *status
: -1, ret
);
350 /* Handle a GNU/Linux extended wait response. If we see a clone
351 event, we need to add the new LWP to our list (and not report the
352 trap to higher layers). */
355 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
357 int event
= wstat
>> 16;
358 struct lwp_info
*new_lwp
;
360 if (event
== PTRACE_EVENT_CLONE
)
363 unsigned long new_pid
;
364 int ret
, status
= W_STOPCODE (SIGSTOP
);
366 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), 0, &new_pid
);
368 /* If we haven't already seen the new PID stop, wait for it now. */
369 if (! pull_pid_from_list (&stopped_pids
, new_pid
))
371 /* The new child has a pending SIGSTOP. We can't affect it until it
372 hits the SIGSTOP, but we're already attached. */
374 ret
= my_waitpid (new_pid
, &status
, __WALL
);
377 perror_with_name ("waiting for new child");
378 else if (ret
!= new_pid
)
379 warning ("wait returned unexpected PID %d", ret
);
380 else if (!WIFSTOPPED (status
))
381 warning ("wait returned unexpected status 0x%x", status
);
384 ptrace (PTRACE_SETOPTIONS
, new_pid
, 0, PTRACE_O_TRACECLONE
);
386 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
387 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
388 add_thread (ptid
, new_lwp
);
390 /* Either we're going to immediately resume the new thread
391 or leave it stopped. linux_resume_one_lwp is a nop if it
392 thinks the thread is currently running, so set this first
393 before calling linux_resume_one_lwp. */
394 new_lwp
->stopped
= 1;
396 /* Normally we will get the pending SIGSTOP. But in some cases
397 we might get another signal delivered to the group first.
398 If we do get another signal, be sure not to lose it. */
399 if (WSTOPSIG (status
) == SIGSTOP
)
401 if (! stopping_threads
)
402 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
406 new_lwp
->stop_expected
= 1;
407 if (stopping_threads
)
409 new_lwp
->status_pending_p
= 1;
410 new_lwp
->status_pending
= status
;
413 /* Pass the signal on. This is what GDB does - except
414 shouldn't we really report it instead? */
415 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
418 /* Always resume the current thread. If we are stopping
419 threads, it will have a pending SIGSTOP; we may as well
421 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
425 /* This function should only be called if the process got a SIGTRAP.
426 The SIGTRAP could mean several things.
428 On i386, where decr_pc_after_break is non-zero:
429 If we were single-stepping this process using PTRACE_SINGLESTEP,
430 we will get only the one SIGTRAP (even if the instruction we
431 stepped over was a breakpoint). The value of $eip will be the
433 If we continue the process using PTRACE_CONT, we will get a
434 SIGTRAP when we hit a breakpoint. The value of $eip will be
435 the instruction after the breakpoint (i.e. needs to be
436 decremented). If we report the SIGTRAP to GDB, we must also
437 report the undecremented PC. If we cancel the SIGTRAP, we
438 must resume at the decremented PC.
440 (Presumably, not yet tested) On a non-decr_pc_after_break machine
441 with hardware or kernel single-step:
442 If we single-step over a breakpoint instruction, our PC will
443 point at the following instruction. If we continue and hit a
444 breakpoint instruction, our PC will point at the breakpoint
450 CORE_ADDR stop_pc
= (*the_low_target
.get_pc
) ();
452 if (! get_thread_lwp (current_inferior
)->stepping
)
453 stop_pc
-= the_low_target
.decr_pc_after_break
;
456 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
462 add_lwp (ptid_t ptid
)
464 struct lwp_info
*lwp
;
466 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
467 memset (lwp
, 0, sizeof (*lwp
));
471 if (the_low_target
.new_thread
!= NULL
)
472 lwp
->arch_private
= the_low_target
.new_thread ();
474 add_inferior_to_list (&all_lwps
, &lwp
->head
);
479 /* Start an inferior process and returns its pid.
480 ALLARGS is a vector of program-name and args. */
483 linux_create_inferior (char *program
, char **allargs
)
485 struct lwp_info
*new_lwp
;
489 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
495 perror_with_name ("fork");
499 ptrace (PTRACE_TRACEME
, 0, 0, 0);
501 signal (__SIGRTMIN
+ 1, SIG_DFL
);
505 execv (program
, allargs
);
507 execvp (program
, allargs
);
509 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
515 linux_add_process (pid
, 0);
517 ptid
= ptid_build (pid
, pid
, 0);
518 new_lwp
= add_lwp (ptid
);
519 add_thread (ptid
, new_lwp
);
520 new_lwp
->must_set_ptrace_flags
= 1;
525 /* Attach to an inferior process. */
528 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
531 struct lwp_info
*new_lwp
;
533 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) != 0)
537 /* If we fail to attach to an LWP, just warn. */
538 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
539 strerror (errno
), errno
);
544 /* If we fail to attach to a process, report an error. */
545 error ("Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
546 strerror (errno
), errno
);
550 /* NOTE/FIXME: This lwp might have not been the tgid. */
551 ptid
= ptid_build (lwpid
, lwpid
, 0);
554 /* Note that extracting the pid from the current inferior is
555 safe, since we're always called in the context of the same
556 process as this new thread. */
557 int pid
= pid_of (get_thread_lwp (current_inferior
));
558 ptid
= ptid_build (pid
, lwpid
, 0);
561 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
562 add_thread (ptid
, new_lwp
);
564 /* We need to wait for SIGSTOP before being able to make the next
565 ptrace call on this LWP. */
566 new_lwp
->must_set_ptrace_flags
= 1;
568 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
571 There are several cases to consider here:
573 1) gdbserver has already attached to the process and is being notified
574 of a new thread that is being created.
575 In this case we should ignore that SIGSTOP and resume the process.
576 This is handled below by setting stop_expected = 1.
578 2) This is the first thread (the process thread), and we're attaching
579 to it via attach_inferior.
580 In this case we want the process thread to stop.
581 This is handled by having linux_attach clear stop_expected after
583 ??? If the process already has several threads we leave the other
586 3) GDB is connecting to gdbserver and is requesting an enumeration of all
588 In this case we want the thread to stop.
589 FIXME: This case is currently not properly handled.
590 We should wait for the SIGSTOP but don't. Things work apparently
591 because enough time passes between when we ptrace (ATTACH) and when
592 gdb makes the next ptrace call on the thread.
594 On the other hand, if we are currently trying to stop all threads, we
595 should treat the new thread as if we had sent it a SIGSTOP. This works
596 because we are guaranteed that the add_lwp call above added us to the
597 end of the list, and so the new thread has not yet reached
598 wait_for_sigstop (but will). */
599 if (! stopping_threads
)
600 new_lwp
->stop_expected
= 1;
604 linux_attach_lwp (unsigned long lwpid
)
606 linux_attach_lwp_1 (lwpid
, 0);
610 linux_attach (unsigned long pid
)
612 struct lwp_info
*lwp
;
614 linux_attach_lwp_1 (pid
, 1);
616 linux_add_process (pid
, 1);
620 /* Don't ignore the initial SIGSTOP if we just attached to this
621 process. It will be collected by wait shortly. */
622 lwp
= (struct lwp_info
*) find_inferior_id (&all_lwps
,
623 ptid_build (pid
, pid
, 0));
624 lwp
->stop_expected
= 0;
637 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
639 struct counter
*counter
= args
;
641 if (ptid_get_pid (entry
->id
) == counter
->pid
)
643 if (++counter
->count
> 1)
651 last_thread_of_process_p (struct thread_info
*thread
)
653 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
654 int pid
= ptid_get_pid (ptid
);
655 struct counter counter
= { pid
, 0 };
657 return (find_inferior (&all_threads
,
658 second_thread_of_pid_p
, &counter
) == NULL
);
661 /* Kill the inferior lwp. */
664 linux_kill_one_lwp (struct inferior_list_entry
*entry
, void *args
)
666 struct thread_info
*thread
= (struct thread_info
*) entry
;
667 struct lwp_info
*lwp
= get_thread_lwp (thread
);
669 int pid
= * (int *) args
;
671 if (ptid_get_pid (entry
->id
) != pid
)
674 /* We avoid killing the first thread here, because of a Linux kernel (at
675 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
676 the children get a chance to be reaped, it will remain a zombie
679 if (lwpid_of (lwp
) == pid
)
682 fprintf (stderr
, "lkop: is last of process %s\n",
683 target_pid_to_str (entry
->id
));
687 /* If we're killing a running inferior, make sure it is stopped
688 first, as PTRACE_KILL will not work otherwise. */
690 send_sigstop (&lwp
->head
);
694 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
696 /* Make sure it died. The loop is most likely unnecessary. */
697 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
698 } while (pid
> 0 && WIFSTOPPED (wstat
));
706 struct process_info
*process
;
707 struct lwp_info
*lwp
;
708 struct thread_info
*thread
;
712 process
= find_process_pid (pid
);
716 find_inferior (&all_threads
, linux_kill_one_lwp
, &pid
);
718 /* See the comment in linux_kill_one_lwp. We did not kill the first
719 thread in the list, so do so now. */
720 lwp
= find_lwp_pid (pid_to_ptid (pid
));
721 thread
= get_lwp_thread (lwp
);
724 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
725 lwpid_of (lwp
), pid
);
727 /* If we're killing a running inferior, make sure it is stopped
728 first, as PTRACE_KILL will not work otherwise. */
730 send_sigstop (&lwp
->head
);
734 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
736 /* Make sure it died. The loop is most likely unnecessary. */
737 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
738 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
741 thread_db_free (process
, 0);
744 linux_remove_process (process
);
749 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
751 struct thread_info
*thread
= (struct thread_info
*) entry
;
752 struct lwp_info
*lwp
= get_thread_lwp (thread
);
753 int pid
= * (int *) args
;
755 if (ptid_get_pid (entry
->id
) != pid
)
758 /* If we're detaching from a running inferior, make sure it is
759 stopped first, as PTRACE_DETACH will not work otherwise. */
762 int lwpid
= lwpid_of (lwp
);
764 stopping_threads
= 1;
765 send_sigstop (&lwp
->head
);
767 /* If this detects a new thread through a clone event, the new
768 thread is appended to the end of the lwp list, so we'll
769 eventually detach from it. */
770 wait_for_sigstop (&lwp
->head
);
771 stopping_threads
= 0;
773 /* If LWP exits while we're trying to stop it, there's nothing
775 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
780 /* Make sure the process isn't stopped at a breakpoint that's
782 check_removed_breakpoint (lwp
);
784 /* If this process is stopped but is expecting a SIGSTOP, then make
785 sure we take care of that now. This isn't absolutely guaranteed
786 to collect the SIGSTOP, but is fairly likely to. */
787 if (lwp
->stop_expected
)
790 /* Clear stop_expected, so that the SIGSTOP will be reported. */
791 lwp
->stop_expected
= 0;
793 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
794 linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
797 /* Flush any pending changes to the process's registers. */
798 regcache_invalidate_one ((struct inferior_list_entry
*)
799 get_lwp_thread (lwp
));
801 /* Finally, let it resume. */
802 ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0, 0);
809 any_thread_of (struct inferior_list_entry
*entry
, void *args
)
813 if (ptid_get_pid (entry
->id
) == *pid_p
)
820 linux_detach (int pid
)
822 struct process_info
*process
;
824 process
= find_process_pid (pid
);
829 thread_db_free (process
, 1);
833 (struct thread_info
*) find_inferior (&all_threads
, any_thread_of
, &pid
);
835 delete_all_breakpoints ();
836 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
837 linux_remove_process (process
);
845 struct process_info
*process
;
847 process
= find_process_pid (pid
);
852 ret
= my_waitpid (pid
, &status
, 0);
853 if (WIFEXITED (status
) || WIFSIGNALED (status
))
855 } while (ret
!= -1 || errno
!= ECHILD
);
858 /* Return nonzero if the given thread is still alive. */
860 linux_thread_alive (ptid_t ptid
)
862 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
864 /* We assume we always know if a thread exits. If a whole process
865 exited but we still haven't been able to report it to GDB, we'll
866 hold on to the last lwp of the dead process. */
873 /* Return nonzero if this process stopped at a breakpoint which
874 no longer appears to be inserted. Also adjust the PC
875 appropriately to resume where the breakpoint used to be. */
877 check_removed_breakpoint (struct lwp_info
*event_child
)
880 struct thread_info
*saved_inferior
;
882 if (event_child
->pending_is_breakpoint
== 0)
886 fprintf (stderr
, "Checking for breakpoint in lwp %ld.\n",
887 lwpid_of (event_child
));
889 saved_inferior
= current_inferior
;
890 current_inferior
= get_lwp_thread (event_child
);
892 stop_pc
= get_stop_pc ();
894 /* If the PC has changed since we stopped, then we shouldn't do
895 anything. This happens if, for instance, GDB handled the
896 decr_pc_after_break subtraction itself. */
897 if (stop_pc
!= event_child
->pending_stop_pc
)
900 fprintf (stderr
, "Ignoring, PC was changed. Old PC was 0x%08llx\n",
901 event_child
->pending_stop_pc
);
903 event_child
->pending_is_breakpoint
= 0;
904 current_inferior
= saved_inferior
;
908 /* If the breakpoint is still there, we will report hitting it. */
909 if ((*the_low_target
.breakpoint_at
) (stop_pc
))
912 fprintf (stderr
, "Ignoring, breakpoint is still present.\n");
913 current_inferior
= saved_inferior
;
918 fprintf (stderr
, "Removed breakpoint.\n");
920 /* For decr_pc_after_break targets, here is where we perform the
921 decrement. We go immediately from this function to resuming,
922 and can not safely call get_stop_pc () again. */
923 if (the_low_target
.set_pc
!= NULL
)
926 fprintf (stderr
, "Set pc to 0x%lx\n", (long) stop_pc
);
927 (*the_low_target
.set_pc
) (stop_pc
);
930 /* We consumed the pending SIGTRAP. */
931 event_child
->pending_is_breakpoint
= 0;
932 event_child
->status_pending_p
= 0;
933 event_child
->status_pending
= 0;
935 current_inferior
= saved_inferior
;
939 /* Return 1 if this lwp has an interesting status pending. This
940 function may silently resume an inferior lwp. */
942 status_pending_p (struct inferior_list_entry
*entry
, void *arg
)
944 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
945 ptid_t ptid
= * (ptid_t
*) arg
;
947 /* Check if we're only interested in events from a specific process
949 if (!ptid_equal (minus_one_ptid
, ptid
)
950 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
953 if (lwp
->status_pending_p
&& !lwp
->suspended
)
954 if (check_removed_breakpoint (lwp
))
956 /* This thread was stopped at a breakpoint, and the breakpoint
957 is now gone. We were told to continue (or step...) all threads,
958 so GDB isn't trying to single-step past this breakpoint.
959 So instead of reporting the old SIGTRAP, pretend we got to
960 the breakpoint just after it was removed instead of just
961 before; resume the process. */
962 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
966 return (lwp
->status_pending_p
&& !lwp
->suspended
);
970 same_lwp (struct inferior_list_entry
*entry
, void *data
)
972 ptid_t ptid
= *(ptid_t
*) data
;
975 if (ptid_get_lwp (ptid
) != 0)
976 lwp
= ptid_get_lwp (ptid
);
978 lwp
= ptid_get_pid (ptid
);
980 if (ptid_get_lwp (entry
->id
) == lwp
)
987 find_lwp_pid (ptid_t ptid
)
989 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
992 static struct lwp_info
*
993 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
996 int to_wait_for
= -1;
997 struct lwp_info
*child
= NULL
;
1000 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1002 if (ptid_equal (ptid
, minus_one_ptid
))
1003 to_wait_for
= -1; /* any child */
1005 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1011 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1012 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1015 perror_with_name ("waitpid");
1018 && (!WIFSTOPPED (*wstatp
)
1019 || (WSTOPSIG (*wstatp
) != 32
1020 && WSTOPSIG (*wstatp
) != 33)))
1021 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1023 child
= find_lwp_pid (pid_to_ptid (ret
));
1025 /* If we didn't find a process, one of two things presumably happened:
1026 - A process we started and then detached from has exited. Ignore it.
1027 - A process we are controlling has forked and the new child's stop
1028 was reported to us by the kernel. Save its PID. */
1029 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1031 add_pid_to_list (&stopped_pids
, ret
);
1034 else if (child
== NULL
)
1038 child
->pending_is_breakpoint
= 0;
1040 child
->last_status
= *wstatp
;
1042 /* Architecture-specific setup after inferior is running.
1043 This needs to happen after we have attached to the inferior
1044 and it is stopped for the first time, but before we access
1045 any inferior registers. */
1048 the_low_target
.arch_setup ();
1049 #ifdef HAVE_LINUX_REGSETS
1050 memset (disabled_regsets
, 0, num_regsets
);
1056 && WIFSTOPPED (*wstatp
)
1057 && the_low_target
.get_pc
!= NULL
)
1059 struct thread_info
*saved_inferior
= current_inferior
;
1062 current_inferior
= (struct thread_info
*)
1063 find_inferior_id (&all_threads
, child
->head
.id
);
1064 pc
= (*the_low_target
.get_pc
) ();
1065 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1066 current_inferior
= saved_inferior
;
1072 /* Wait for an event from child PID. If PID is -1, wait for any
1073 child. Store the stop status through the status pointer WSTAT.
1074 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1075 event was found and OPTIONS contains WNOHANG. Return the PID of
1076 the stopped child otherwise. */
1079 linux_wait_for_event_1 (ptid_t ptid
, int *wstat
, int options
)
1082 struct lwp_info
*event_child
= NULL
;
1084 struct lwp_info
*requested_child
= NULL
;
1086 /* Check for a lwp with a pending status. */
1087 /* It is possible that the user changed the pending task's registers since
1088 it stopped. We correctly handle the change of PC if we hit a breakpoint
1089 (in check_removed_breakpoint); signals should be reported anyway. */
1091 if (ptid_equal (ptid
, minus_one_ptid
)
1092 || ptid_equal (pid_to_ptid (ptid_get_pid (ptid
)), ptid
))
1094 event_child
= (struct lwp_info
*)
1095 find_inferior (&all_lwps
, status_pending_p
, &ptid
);
1096 if (debug_threads
&& event_child
)
1097 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1101 requested_child
= find_lwp_pid (ptid
);
1102 if (requested_child
->status_pending_p
1103 && !check_removed_breakpoint (requested_child
))
1104 event_child
= requested_child
;
1107 if (event_child
!= NULL
)
1110 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1111 lwpid_of (event_child
), event_child
->status_pending
);
1112 *wstat
= event_child
->status_pending
;
1113 event_child
->status_pending_p
= 0;
1114 event_child
->status_pending
= 0;
1115 current_inferior
= get_lwp_thread (event_child
);
1116 return lwpid_of (event_child
);
1119 /* We only enter this loop if no process has a pending wait status. Thus
1120 any action taken in response to a wait status inside this loop is
1121 responding as soon as we detect the status, not after any pending
1125 event_child
= linux_wait_for_lwp (ptid
, wstat
, options
);
1127 if ((options
& WNOHANG
) && event_child
== NULL
)
1130 if (event_child
== NULL
)
1131 error ("event from unknown child");
1133 current_inferior
= get_lwp_thread (event_child
);
1135 /* Check for thread exit. */
1136 if (! WIFSTOPPED (*wstat
))
1139 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1141 /* If the last thread is exiting, just return. */
1142 if (last_thread_of_process_p (current_inferior
))
1145 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1146 lwpid_of (event_child
));
1147 return lwpid_of (event_child
);
1150 delete_lwp (event_child
);
1154 current_inferior
= (struct thread_info
*) all_threads
.head
;
1156 fprintf (stderr
, "Current inferior is now %ld\n",
1157 lwpid_of (get_thread_lwp (current_inferior
)));
1161 current_inferior
= NULL
;
1163 fprintf (stderr
, "Current inferior is now <NULL>\n");
1166 /* If we were waiting for this particular child to do something...
1167 well, it did something. */
1168 if (requested_child
!= NULL
)
1169 return lwpid_of (event_child
);
1171 /* Wait for a more interesting event. */
1175 if (event_child
->must_set_ptrace_flags
)
1177 ptrace (PTRACE_SETOPTIONS
, lwpid_of (event_child
),
1178 0, PTRACE_O_TRACECLONE
);
1179 event_child
->must_set_ptrace_flags
= 0;
1182 if (WIFSTOPPED (*wstat
)
1183 && WSTOPSIG (*wstat
) == SIGSTOP
1184 && event_child
->stop_expected
)
1187 fprintf (stderr
, "Expected stop.\n");
1188 event_child
->stop_expected
= 0;
1189 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
1193 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1194 && *wstat
>> 16 != 0)
1196 handle_extended_wait (event_child
, *wstat
);
1200 /* If GDB is not interested in this signal, don't stop other
1201 threads, and don't report it to GDB. Just resume the
1202 inferior right away. We do this for threading-related
1203 signals as well as any that GDB specifically requested we
1204 ignore. But never ignore SIGSTOP if we sent it ourselves,
1205 and do not ignore signals when stepping - they may require
1206 special handling to skip the signal handler. */
1207 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
1209 if (WIFSTOPPED (*wstat
)
1210 && !event_child
->stepping
1212 #ifdef USE_THREAD_DB
1213 (current_process ()->private->thread_db
!= NULL
1214 && (WSTOPSIG (*wstat
) == __SIGRTMIN
1215 || WSTOPSIG (*wstat
) == __SIGRTMIN
+ 1))
1218 (pass_signals
[target_signal_from_host (WSTOPSIG (*wstat
))]
1219 && (WSTOPSIG (*wstat
) != SIGSTOP
|| !stopping_threads
))))
1221 siginfo_t info
, *info_p
;
1224 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
1225 WSTOPSIG (*wstat
), lwpid_of (event_child
));
1227 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
1231 linux_resume_one_lwp (event_child
,
1232 event_child
->stepping
,
1233 WSTOPSIG (*wstat
), info_p
);
1237 /* If this event was not handled above, and is not a SIGTRAP, report
1239 if (!WIFSTOPPED (*wstat
) || WSTOPSIG (*wstat
) != SIGTRAP
)
1240 return lwpid_of (event_child
);
1242 /* If this target does not support breakpoints, we simply report the
1243 SIGTRAP; it's of no concern to us. */
1244 if (the_low_target
.get_pc
== NULL
)
1245 return lwpid_of (event_child
);
1247 stop_pc
= get_stop_pc ();
1249 /* bp_reinsert will only be set if we were single-stepping.
1250 Notice that we will resume the process after hitting
1251 a gdbserver breakpoint; single-stepping to/over one
1252 is not supported (yet). */
1253 if (event_child
->bp_reinsert
!= 0)
1256 fprintf (stderr
, "Reinserted breakpoint.\n");
1257 reinsert_breakpoint (event_child
->bp_reinsert
);
1258 event_child
->bp_reinsert
= 0;
1260 /* Clear the single-stepping flag and SIGTRAP as we resume. */
1261 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1265 bp_status
= check_breakpoints (stop_pc
);
1270 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
1272 /* We hit one of our own breakpoints. We mark it as a pending
1273 breakpoint, so that check_removed_breakpoint () will do the PC
1274 adjustment for us at the appropriate time. */
1275 event_child
->pending_is_breakpoint
= 1;
1276 event_child
->pending_stop_pc
= stop_pc
;
1278 /* We may need to put the breakpoint back. We continue in the event
1279 loop instead of simply replacing the breakpoint right away,
1280 in order to not lose signals sent to the thread that hit the
1281 breakpoint. Unfortunately this increases the window where another
1282 thread could sneak past the removed breakpoint. For the current
1283 use of server-side breakpoints (thread creation) this is
1284 acceptable; but it needs to be considered before this breakpoint
1285 mechanism can be used in more general ways. For some breakpoints
1286 it may be necessary to stop all other threads, but that should
1287 be avoided where possible.
1289 If breakpoint_reinsert_addr is NULL, that means that we can
1290 use PTRACE_SINGLESTEP on this platform. Uninsert the breakpoint,
1291 mark it for reinsertion, and single-step.
1293 Otherwise, call the target function to figure out where we need
1294 our temporary breakpoint, create it, and continue executing this
1297 /* NOTE: we're lifting breakpoints in non-stop mode. This
1298 is currently only used for thread event breakpoints, so
1299 it isn't that bad as long as we have PTRACE_EVENT_CLONE
1302 /* No need to reinsert. */
1303 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1304 else if (the_low_target
.breakpoint_reinsert_addr
== NULL
)
1306 event_child
->bp_reinsert
= stop_pc
;
1307 uninsert_breakpoint (stop_pc
);
1308 linux_resume_one_lwp (event_child
, 1, 0, NULL
);
1312 reinsert_breakpoint_by_bp
1313 (stop_pc
, (*the_low_target
.breakpoint_reinsert_addr
) ());
1314 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1321 fprintf (stderr
, "Hit a non-gdbserver breakpoint.\n");
1323 /* If we were single-stepping, we definitely want to report the
1324 SIGTRAP. Although the single-step operation has completed,
1325 do not clear clear the stepping flag yet; we need to check it
1326 in wait_for_sigstop. */
1327 if (event_child
->stepping
)
1328 return lwpid_of (event_child
);
1330 /* A SIGTRAP that we can't explain. It may have been a breakpoint.
1331 Check if it is a breakpoint, and if so mark the process information
1332 accordingly. This will handle both the necessary fiddling with the
1333 PC on decr_pc_after_break targets and suppressing extra threads
1334 hitting a breakpoint if two hit it at once and then GDB removes it
1335 after the first is reported. Arguably it would be better to report
1336 multiple threads hitting breakpoints simultaneously, but the current
1337 remote protocol does not allow this. */
1338 if ((*the_low_target
.breakpoint_at
) (stop_pc
))
1340 event_child
->pending_is_breakpoint
= 1;
1341 event_child
->pending_stop_pc
= stop_pc
;
1344 return lwpid_of (event_child
);
1352 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1356 if (ptid_is_pid (ptid
))
1358 /* A request to wait for a specific tgid. This is not possible
1359 with waitpid, so instead, we wait for any child, and leave
1360 children we're not interested in right now with a pending
1361 status to report later. */
1362 wait_ptid
= minus_one_ptid
;
1371 event_pid
= linux_wait_for_event_1 (wait_ptid
, wstat
, options
);
1374 && ptid_is_pid (ptid
) && ptid_get_pid (ptid
) != event_pid
)
1376 struct lwp_info
*event_child
= find_lwp_pid (pid_to_ptid (event_pid
));
1378 if (! WIFSTOPPED (*wstat
))
1379 mark_lwp_dead (event_child
, *wstat
);
1382 event_child
->status_pending_p
= 1;
1383 event_child
->status_pending
= *wstat
;
1391 /* Wait for process, returns status. */
1394 linux_wait_1 (ptid_t ptid
,
1395 struct target_waitstatus
*ourstatus
, int target_options
)
1398 struct thread_info
*thread
= NULL
;
1399 struct lwp_info
*lwp
= NULL
;
1403 /* Translate generic target options into linux options. */
1405 if (target_options
& TARGET_WNOHANG
)
1409 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
1411 /* If we were only supposed to resume one thread, only wait for
1412 that thread - if it's still alive. If it died, however - which
1413 can happen if we're coming from the thread death case below -
1414 then we need to make sure we restart the other threads. We could
1415 pick a thread at random or restart all; restarting all is less
1418 && !ptid_equal (cont_thread
, null_ptid
)
1419 && !ptid_equal (cont_thread
, minus_one_ptid
))
1421 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
1424 /* No stepping, no signal - unless one is pending already, of course. */
1427 struct thread_resume resume_info
;
1428 resume_info
.thread
= minus_one_ptid
;
1429 resume_info
.kind
= resume_continue
;
1430 resume_info
.sig
= 0;
1431 linux_resume (&resume_info
, 1);
1437 pid
= linux_wait_for_event (ptid
, &w
, options
);
1438 if (pid
== 0) /* only if TARGET_WNOHANG */
1441 lwp
= get_thread_lwp (current_inferior
);
1443 /* If we are waiting for a particular child, and it exited,
1444 linux_wait_for_event will return its exit status. Similarly if
1445 the last child exited. If this is not the last child, however,
1446 do not report it as exited until there is a 'thread exited' response
1447 available in the remote protocol. Instead, just wait for another event.
1448 This should be safe, because if the thread crashed we will already
1449 have reported the termination signal to GDB; that should stop any
1450 in-progress stepping operations, etc.
1452 Report the exit status of the last thread to exit. This matches
1453 LinuxThreads' behavior. */
1455 if (last_thread_of_process_p (current_inferior
))
1457 if (WIFEXITED (w
) || WIFSIGNALED (w
))
1459 int pid
= pid_of (lwp
);
1460 struct process_info
*process
= find_process_pid (pid
);
1462 #ifdef USE_THREAD_DB
1463 thread_db_free (process
, 0);
1466 linux_remove_process (process
);
1468 current_inferior
= NULL
;
1472 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
1473 ourstatus
->value
.integer
= WEXITSTATUS (w
);
1476 fprintf (stderr
, "\nChild exited with retcode = %x \n", WEXITSTATUS (w
));
1480 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
1481 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
1484 fprintf (stderr
, "\nChild terminated with signal = %x \n", WTERMSIG (w
));
1488 return pid_to_ptid (pid
);
1493 if (!WIFSTOPPED (w
))
1497 /* In all-stop, stop all threads. Be careful to only do this if
1498 we're about to report an event to GDB. */
1502 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
1504 if (lwp
->suspended
&& WSTOPSIG (w
) == SIGSTOP
)
1506 /* A thread that has been requested to stop by GDB with vCont;t,
1507 and it stopped cleanly, so report as SIG0. The use of
1508 SIGSTOP is an implementation detail. */
1509 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
1511 else if (lwp
->suspended
&& WSTOPSIG (w
) != SIGSTOP
)
1513 /* A thread that has been requested to stop by GDB with vCont;t,
1514 but, it stopped for other reasons. Set stop_expected so the
1515 pending SIGSTOP is ignored and the LWP is resumed. */
1516 lwp
->stop_expected
= 1;
1517 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
1521 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
1525 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
1526 target_pid_to_str (lwp
->head
.id
),
1528 ourstatus
->value
.sig
);
1530 return lwp
->head
.id
;
1533 /* Get rid of any pending event in the pipe. */
1535 async_file_flush (void)
1541 ret
= read (linux_event_pipe
[0], &buf
, 1);
1542 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
1545 /* Put something in the pipe, so the event loop wakes up. */
1547 async_file_mark (void)
1551 async_file_flush ();
1554 ret
= write (linux_event_pipe
[1], "+", 1);
1555 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
1557 /* Ignore EAGAIN. If the pipe is full, the event loop will already
1558 be awakened anyway. */
1562 linux_wait (ptid_t ptid
,
1563 struct target_waitstatus
*ourstatus
, int target_options
)
1568 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
1570 /* Flush the async file first. */
1571 if (target_is_async_p ())
1572 async_file_flush ();
1574 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
1576 /* If at least one stop was reported, there may be more. A single
1577 SIGCHLD can signal more than one child stop. */
1578 if (target_is_async_p ()
1579 && (target_options
& TARGET_WNOHANG
) != 0
1580 && !ptid_equal (event_ptid
, null_ptid
))
1586 /* Send a signal to an LWP. */
1589 kill_lwp (unsigned long lwpid
, int signo
)
1591 /* Use tkill, if possible, in case we are using nptl threads. If tkill
1592 fails, then we are not using nptl threads and we should be using kill. */
1596 static int tkill_failed
;
1603 ret
= syscall (__NR_tkill
, lwpid
, signo
);
1604 if (errno
!= ENOSYS
)
1611 return kill (lwpid
, signo
);
1615 send_sigstop (struct inferior_list_entry
*entry
)
1617 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1623 pid
= lwpid_of (lwp
);
1625 /* If we already have a pending stop signal for this process, don't
1627 if (lwp
->stop_expected
)
1630 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
1632 /* We clear the stop_expected flag so that wait_for_sigstop
1633 will receive the SIGSTOP event (instead of silently resuming and
1634 waiting again). It'll be reset below. */
1635 lwp
->stop_expected
= 0;
1640 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
1642 kill_lwp (pid
, SIGSTOP
);
1646 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
1648 /* It's dead, really. */
1651 /* Store the exit status for later. */
1652 lwp
->status_pending_p
= 1;
1653 lwp
->status_pending
= wstat
;
1655 /* So that check_removed_breakpoint doesn't try to figure out if
1656 this is stopped at a breakpoint. */
1657 lwp
->pending_is_breakpoint
= 0;
1659 /* Prevent trying to stop it. */
1662 /* No further stops are expected from a dead lwp. */
1663 lwp
->stop_expected
= 0;
1667 wait_for_sigstop (struct inferior_list_entry
*entry
)
1669 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1670 struct thread_info
*saved_inferior
;
1678 saved_inferior
= current_inferior
;
1679 if (saved_inferior
!= NULL
)
1680 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
1682 saved_tid
= null_ptid
; /* avoid bogus unused warning */
1684 ptid
= lwp
->head
.id
;
1686 linux_wait_for_event (ptid
, &wstat
, __WALL
);
1688 /* If we stopped with a non-SIGSTOP signal, save it for later
1689 and record the pending SIGSTOP. If the process exited, just
1691 if (WIFSTOPPED (wstat
)
1692 && WSTOPSIG (wstat
) != SIGSTOP
)
1695 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
1696 lwpid_of (lwp
), wstat
);
1698 /* Do not leave a pending single-step finish to be reported to
1699 the client. The client will give us a new action for this
1700 thread, possibly a continue request --- otherwise, the client
1701 would consider this pending SIGTRAP reported later a spurious
1703 if (WSTOPSIG (wstat
) == SIGTRAP
1705 && !linux_stopped_by_watchpoint ())
1708 fprintf (stderr
, " single-step SIGTRAP ignored\n");
1712 lwp
->status_pending_p
= 1;
1713 lwp
->status_pending
= wstat
;
1715 lwp
->stop_expected
= 1;
1717 else if (!WIFSTOPPED (wstat
))
1720 fprintf (stderr
, "Process %ld exited while stopping LWPs\n",
1723 /* Leave this status pending for the next time we're able to
1724 report it. In the mean time, we'll report this lwp as dead
1725 to GDB, so GDB doesn't try to read registers and memory from
1727 mark_lwp_dead (lwp
, wstat
);
1730 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
1731 current_inferior
= saved_inferior
;
1735 fprintf (stderr
, "Previously current thread died.\n");
1739 /* We can't change the current inferior behind GDB's back,
1740 otherwise, a subsequent command may apply to the wrong
1742 current_inferior
= NULL
;
1746 /* Set a valid thread as current. */
1747 set_desired_inferior (0);
1753 stop_all_lwps (void)
1755 stopping_threads
= 1;
1756 for_each_inferior (&all_lwps
, send_sigstop
);
1757 for_each_inferior (&all_lwps
, wait_for_sigstop
);
1758 stopping_threads
= 0;
1761 /* Resume execution of the inferior process.
1762 If STEP is nonzero, single-step it.
1763 If SIGNAL is nonzero, give it that signal. */
1766 linux_resume_one_lwp (struct lwp_info
*lwp
,
1767 int step
, int signal
, siginfo_t
*info
)
1769 struct thread_info
*saved_inferior
;
1771 if (lwp
->stopped
== 0)
1774 /* If we have pending signals or status, and a new signal, enqueue the
1775 signal. Also enqueue the signal if we are waiting to reinsert a
1776 breakpoint; it will be picked up again below. */
1778 && (lwp
->status_pending_p
|| lwp
->pending_signals
!= NULL
1779 || lwp
->bp_reinsert
!= 0))
1781 struct pending_signals
*p_sig
;
1782 p_sig
= xmalloc (sizeof (*p_sig
));
1783 p_sig
->prev
= lwp
->pending_signals
;
1784 p_sig
->signal
= signal
;
1786 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1788 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
1789 lwp
->pending_signals
= p_sig
;
1792 if (lwp
->status_pending_p
&& !check_removed_breakpoint (lwp
))
1795 saved_inferior
= current_inferior
;
1796 current_inferior
= get_lwp_thread (lwp
);
1799 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
1800 lwpid_of (lwp
), step
? "step" : "continue", signal
,
1801 lwp
->stop_expected
? "expected" : "not expected");
1803 /* This bit needs some thinking about. If we get a signal that
1804 we must report while a single-step reinsert is still pending,
1805 we often end up resuming the thread. It might be better to
1806 (ew) allow a stack of pending events; then we could be sure that
1807 the reinsert happened right away and not lose any signals.
1809 Making this stack would also shrink the window in which breakpoints are
1810 uninserted (see comment in linux_wait_for_lwp) but not enough for
1811 complete correctness, so it won't solve that problem. It may be
1812 worthwhile just to solve this one, however. */
1813 if (lwp
->bp_reinsert
!= 0)
1816 fprintf (stderr
, " pending reinsert at %08lx", (long)lwp
->bp_reinsert
);
1818 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
1821 /* Postpone any pending signal. It was enqueued above. */
1825 check_removed_breakpoint (lwp
);
1827 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
1829 CORE_ADDR pc
= (*the_low_target
.get_pc
) ();
1830 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
1833 /* If we have pending signals, consume one unless we are trying to reinsert
1835 if (lwp
->pending_signals
!= NULL
&& lwp
->bp_reinsert
== 0)
1837 struct pending_signals
**p_sig
;
1839 p_sig
= &lwp
->pending_signals
;
1840 while ((*p_sig
)->prev
!= NULL
)
1841 p_sig
= &(*p_sig
)->prev
;
1843 signal
= (*p_sig
)->signal
;
1844 if ((*p_sig
)->info
.si_signo
!= 0)
1845 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
1851 if (the_low_target
.prepare_to_resume
!= NULL
)
1852 the_low_target
.prepare_to_resume (lwp
);
1854 regcache_invalidate_one ((struct inferior_list_entry
*)
1855 get_lwp_thread (lwp
));
1858 lwp
->stepping
= step
;
1859 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0, signal
);
1861 current_inferior
= saved_inferior
;
1864 /* ESRCH from ptrace either means that the thread was already
1865 running (an error) or that it is gone (a race condition). If
1866 it's gone, we will get a notification the next time we wait,
1867 so we can ignore the error. We could differentiate these
1868 two, but it's tricky without waiting; the thread still exists
1869 as a zombie, so sending it signal 0 would succeed. So just
1874 perror_with_name ("ptrace");
1878 struct thread_resume_array
1880 struct thread_resume
*resume
;
1884 /* This function is called once per thread. We look up the thread
1885 in RESUME_PTR, and mark the thread with a pointer to the appropriate
1888 This algorithm is O(threads * resume elements), but resume elements
1889 is small (and will remain small at least until GDB supports thread
1892 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
1894 struct lwp_info
*lwp
;
1895 struct thread_info
*thread
;
1897 struct thread_resume_array
*r
;
1899 thread
= (struct thread_info
*) entry
;
1900 lwp
= get_thread_lwp (thread
);
1903 for (ndx
= 0; ndx
< r
->n
; ndx
++)
1905 ptid_t ptid
= r
->resume
[ndx
].thread
;
1906 if (ptid_equal (ptid
, minus_one_ptid
)
1907 || ptid_equal (ptid
, entry
->id
)
1908 || (ptid_is_pid (ptid
)
1909 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
1910 || (ptid_get_lwp (ptid
) == -1
1911 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
1913 lwp
->resume
= &r
->resume
[ndx
];
1918 /* No resume action for this thread. */
1925 /* Set *FLAG_P if this lwp has an interesting status pending. */
1927 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
1929 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1931 /* LWPs which will not be resumed are not interesting, because
1932 we might not wait for them next time through linux_wait. */
1933 if (lwp
->resume
== NULL
)
1936 /* If this thread has a removed breakpoint, we won't have any
1937 events to report later, so check now. check_removed_breakpoint
1938 may clear status_pending_p. We avoid calling check_removed_breakpoint
1939 for any thread that we are not otherwise going to resume - this
1940 lets us preserve stopped status when two threads hit a breakpoint.
1941 GDB removes the breakpoint to single-step a particular thread
1942 past it, then re-inserts it and resumes all threads. We want
1943 to report the second thread without resuming it in the interim. */
1944 if (lwp
->status_pending_p
)
1945 check_removed_breakpoint (lwp
);
1947 if (lwp
->status_pending_p
)
1948 * (int *) flag_p
= 1;
1953 /* This function is called once per thread. We check the thread's resume
1954 request, which will tell us whether to resume, step, or leave the thread
1955 stopped; and what signal, if any, it should be sent.
1957 For threads which we aren't explicitly told otherwise, we preserve
1958 the stepping flag; this is used for stepping over gdbserver-placed
1961 If pending_flags was set in any thread, we queue any needed
1962 signals, since we won't actually resume. We already have a pending
1963 event to report, so we don't need to preserve any step requests;
1964 they should be re-issued if necessary. */
1967 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
1969 struct lwp_info
*lwp
;
1970 struct thread_info
*thread
;
1972 int pending_flag
= * (int *) arg
;
1974 thread
= (struct thread_info
*) entry
;
1975 lwp
= get_thread_lwp (thread
);
1977 if (lwp
->resume
== NULL
)
1980 if (lwp
->resume
->kind
== resume_stop
)
1983 fprintf (stderr
, "suspending LWP %ld\n", lwpid_of (lwp
));
1988 fprintf (stderr
, "running -> suspending LWP %ld\n", lwpid_of (lwp
));
1991 send_sigstop (&lwp
->head
);
1998 fprintf (stderr
, "already stopped/suspended LWP %ld\n",
2001 fprintf (stderr
, "already stopped/not suspended LWP %ld\n",
2005 /* Make sure we leave the LWP suspended, so we don't try to
2006 resume it without GDB telling us to. FIXME: The LWP may
2007 have been stopped in an internal event that was not meant
2008 to be notified back to GDB (e.g., gdbserver breakpoint),
2009 so we should be reporting a stop event in that case
2014 /* For stop requests, we're done. */
2021 /* If this thread which is about to be resumed has a pending status,
2022 then don't resume any threads - we can just report the pending
2023 status. Make sure to queue any signals that would otherwise be
2024 sent. In all-stop mode, we do this decision based on if *any*
2025 thread has a pending status. */
2027 resume_status_pending_p (&lwp
->head
, &pending_flag
);
2032 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
2034 if (ptid_equal (lwp
->resume
->thread
, minus_one_ptid
)
2036 && lwp
->pending_is_breakpoint
)
2039 step
= (lwp
->resume
->kind
== resume_step
);
2041 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
2046 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
2048 /* If we have a new signal, enqueue the signal. */
2049 if (lwp
->resume
->sig
!= 0)
2051 struct pending_signals
*p_sig
;
2052 p_sig
= xmalloc (sizeof (*p_sig
));
2053 p_sig
->prev
= lwp
->pending_signals
;
2054 p_sig
->signal
= lwp
->resume
->sig
;
2055 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
2057 /* If this is the same signal we were previously stopped by,
2058 make sure to queue its siginfo. We can ignore the return
2059 value of ptrace; if it fails, we'll skip
2060 PTRACE_SETSIGINFO. */
2061 if (WIFSTOPPED (lwp
->last_status
)
2062 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
2063 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
2065 lwp
->pending_signals
= p_sig
;
2074 linux_resume (struct thread_resume
*resume_info
, size_t n
)
2077 struct thread_resume_array array
= { resume_info
, n
};
2079 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
2081 /* If there is a thread which would otherwise be resumed, which
2082 has a pending status, then don't resume any threads - we can just
2083 report the pending status. Make sure to queue any signals
2084 that would otherwise be sent. In non-stop mode, we'll apply this
2085 logic to each thread individually. */
2088 find_inferior (&all_lwps
, resume_status_pending_p
, &pending_flag
);
2093 fprintf (stderr
, "Not resuming, pending status\n");
2095 fprintf (stderr
, "Resuming, no pending status\n");
2098 find_inferior (&all_threads
, linux_resume_one_thread
, &pending_flag
);
2101 #ifdef HAVE_LINUX_USRREGS
2104 register_addr (int regnum
)
2108 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
2109 error ("Invalid register number %d.", regnum
);
2111 addr
= the_low_target
.regmap
[regnum
];
2116 /* Fetch one register. */
2118 fetch_register (int regno
)
2125 if (regno
>= the_low_target
.num_regs
)
2127 if ((*the_low_target
.cannot_fetch_register
) (regno
))
2130 regaddr
= register_addr (regno
);
2134 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2135 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2136 & - sizeof (PTRACE_XFER_TYPE
));
2137 buf
= alloca (size
);
2138 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
2141 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
2142 ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_ARG3_TYPE
) regaddr
, 0);
2143 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
2146 /* Warning, not error, in case we are attached; sometimes the
2147 kernel doesn't let us at the registers. */
2148 char *err
= strerror (errno
);
2149 char *msg
= alloca (strlen (err
) + 128);
2150 sprintf (msg
, "reading register %d: %s", regno
, err
);
2156 if (the_low_target
.supply_ptrace_register
)
2157 the_low_target
.supply_ptrace_register (regno
, buf
);
2159 supply_register (regno
, buf
);
2164 /* Fetch all registers, or just one, from the child process. */
2166 usr_fetch_inferior_registers (int regno
)
2169 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
2170 fetch_register (regno
);
2172 fetch_register (regno
);
2175 /* Store our register values back into the inferior.
2176 If REGNO is -1, do this for all registers.
2177 Otherwise, REGNO specifies which register (so we can save time). */
2179 usr_store_inferior_registers (int regno
)
2188 if (regno
>= the_low_target
.num_regs
)
2191 if ((*the_low_target
.cannot_store_register
) (regno
) == 1)
2194 regaddr
= register_addr (regno
);
2198 size
= (register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2199 & - sizeof (PTRACE_XFER_TYPE
);
2200 buf
= alloca (size
);
2201 memset (buf
, 0, size
);
2203 if (the_low_target
.collect_ptrace_register
)
2204 the_low_target
.collect_ptrace_register (regno
, buf
);
2206 collect_register (regno
, buf
);
2208 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2209 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
2212 ptrace (PTRACE_POKEUSER
, pid
, (PTRACE_ARG3_TYPE
) regaddr
,
2213 *(PTRACE_XFER_TYPE
*) (buf
+ i
));
2216 /* At this point, ESRCH should mean the process is
2217 already gone, in which case we simply ignore attempts
2218 to change its registers. See also the related
2219 comment in linux_resume_one_lwp. */
2223 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
2225 char *err
= strerror (errno
);
2226 char *msg
= alloca (strlen (err
) + 128);
2227 sprintf (msg
, "writing register %d: %s",
2233 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
2237 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
2238 usr_store_inferior_registers (regno
);
2240 #endif /* HAVE_LINUX_USRREGS */
2244 #ifdef HAVE_LINUX_REGSETS
2247 regsets_fetch_inferior_registers ()
2249 struct regset_info
*regset
;
2250 int saw_general_regs
= 0;
2253 regset
= target_regsets
;
2255 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2256 while (regset
->size
>= 0)
2261 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
2267 buf
= xmalloc (regset
->size
);
2269 res
= ptrace (regset
->get_request
, pid
, 0, buf
);
2271 res
= ptrace (regset
->get_request
, pid
, buf
, 0);
2277 /* If we get EIO on a regset, do not try it again for
2279 disabled_regsets
[regset
- target_regsets
] = 1;
2286 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
2291 else if (regset
->type
== GENERAL_REGS
)
2292 saw_general_regs
= 1;
2293 regset
->store_function (buf
);
2297 if (saw_general_regs
)
2304 regsets_store_inferior_registers ()
2306 struct regset_info
*regset
;
2307 int saw_general_regs
= 0;
2310 regset
= target_regsets
;
2312 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2313 while (regset
->size
>= 0)
2318 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
2324 buf
= xmalloc (regset
->size
);
2326 /* First fill the buffer with the current register set contents,
2327 in case there are any items in the kernel's regset that are
2328 not in gdbserver's regcache. */
2330 res
= ptrace (regset
->get_request
, pid
, 0, buf
);
2332 res
= ptrace (regset
->get_request
, pid
, buf
, 0);
2337 /* Then overlay our cached registers on that. */
2338 regset
->fill_function (buf
);
2340 /* Only now do we write the register set. */
2342 res
= ptrace (regset
->set_request
, pid
, 0, buf
);
2344 res
= ptrace (regset
->set_request
, pid
, buf
, 0);
2352 /* If we get EIO on a regset, do not try it again for
2354 disabled_regsets
[regset
- target_regsets
] = 1;
2358 else if (errno
== ESRCH
)
2360 /* At this point, ESRCH should mean the process is
2361 already gone, in which case we simply ignore attempts
2362 to change its registers. See also the related
2363 comment in linux_resume_one_lwp. */
2369 perror ("Warning: ptrace(regsets_store_inferior_registers)");
2372 else if (regset
->type
== GENERAL_REGS
)
2373 saw_general_regs
= 1;
2377 if (saw_general_regs
)
2384 #endif /* HAVE_LINUX_REGSETS */
2388 linux_fetch_registers (int regno
)
2390 #ifdef HAVE_LINUX_REGSETS
2391 if (regsets_fetch_inferior_registers () == 0)
2394 #ifdef HAVE_LINUX_USRREGS
2395 usr_fetch_inferior_registers (regno
);
2400 linux_store_registers (int regno
)
2402 #ifdef HAVE_LINUX_REGSETS
2403 if (regsets_store_inferior_registers () == 0)
2406 #ifdef HAVE_LINUX_USRREGS
2407 usr_store_inferior_registers (regno
);
2412 /* Copy LEN bytes from inferior's memory starting at MEMADDR
2413 to debugger memory starting at MYADDR. */
2416 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
2419 /* Round starting address down to longword boundary. */
2420 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
2421 /* Round ending address up; get number of longwords that makes. */
2423 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2424 / sizeof (PTRACE_XFER_TYPE
);
2425 /* Allocate buffer of that many longwords. */
2426 register PTRACE_XFER_TYPE
*buffer
2427 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
2430 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2432 /* Try using /proc. Don't bother for one word. */
2433 if (len
>= 3 * sizeof (long))
2435 /* We could keep this file open and cache it - possibly one per
2436 thread. That requires some juggling, but is even faster. */
2437 sprintf (filename
, "/proc/%d/mem", pid
);
2438 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
2442 /* If pread64 is available, use it. It's faster if the kernel
2443 supports it (only one syscall), and it's 64-bit safe even on
2444 32-bit platforms (for instance, SPARC debugging a SPARC64
2447 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
2449 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, myaddr
, len
) != len
)
2461 /* Read all the longwords */
2462 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
2465 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
, (PTRACE_ARG3_TYPE
) addr
, 0);
2470 /* Copy appropriate bytes out of the buffer. */
2472 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
2478 /* Copy LEN bytes of data from debugger memory at MYADDR
2479 to inferior's memory at MEMADDR.
2480 On failure (cannot write the inferior)
2481 returns the value of errno. */
2484 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
2487 /* Round starting address down to longword boundary. */
2488 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
2489 /* Round ending address up; get number of longwords that makes. */
2491 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1) / sizeof (PTRACE_XFER_TYPE
);
2492 /* Allocate buffer of that many longwords. */
2493 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
2494 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2498 /* Dump up to four bytes. */
2499 unsigned int val
= * (unsigned int *) myaddr
;
2505 val
= val
& 0xffffff;
2506 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
2507 val
, (long)memaddr
);
2510 /* Fill start and end extra bytes of buffer with existing memory data. */
2512 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
, (PTRACE_ARG3_TYPE
) addr
, 0);
2517 = ptrace (PTRACE_PEEKTEXT
, pid
,
2518 (PTRACE_ARG3_TYPE
) (addr
+ (count
- 1)
2519 * sizeof (PTRACE_XFER_TYPE
)),
2523 /* Copy data to be written over corresponding part of buffer */
2525 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)), myaddr
, len
);
2527 /* Write the entire buffer. */
2529 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
2532 ptrace (PTRACE_POKETEXT
, pid
, (PTRACE_ARG3_TYPE
) addr
, buffer
[i
]);
2540 static int linux_supports_tracefork_flag
;
2542 /* Helper functions for linux_test_for_tracefork, called via clone (). */
2545 linux_tracefork_grandchild (void *arg
)
2550 #define STACK_SIZE 4096
2553 linux_tracefork_child (void *arg
)
2555 ptrace (PTRACE_TRACEME
, 0, 0, 0);
2556 kill (getpid (), SIGSTOP
);
2558 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
2559 CLONE_VM
| SIGCHLD
, NULL
);
2561 clone (linux_tracefork_grandchild
, arg
+ STACK_SIZE
,
2562 CLONE_VM
| SIGCHLD
, NULL
);
2567 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
2568 sure that we can enable the option, and that it had the desired
2572 linux_test_for_tracefork (void)
2574 int child_pid
, ret
, status
;
2576 char *stack
= xmalloc (STACK_SIZE
* 4);
2578 linux_supports_tracefork_flag
= 0;
2580 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
2582 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
2583 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
2585 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
2586 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
2588 if (child_pid
== -1)
2589 perror_with_name ("clone");
2591 ret
= my_waitpid (child_pid
, &status
, 0);
2593 perror_with_name ("waitpid");
2594 else if (ret
!= child_pid
)
2595 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
2596 if (! WIFSTOPPED (status
))
2597 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
2599 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0, PTRACE_O_TRACEFORK
);
2602 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
2605 warning ("linux_test_for_tracefork: failed to kill child");
2609 ret
= my_waitpid (child_pid
, &status
, 0);
2610 if (ret
!= child_pid
)
2611 warning ("linux_test_for_tracefork: failed to wait for killed child");
2612 else if (!WIFSIGNALED (status
))
2613 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
2614 "killed child", status
);
2619 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
2621 warning ("linux_test_for_tracefork: failed to resume child");
2623 ret
= my_waitpid (child_pid
, &status
, 0);
2625 if (ret
== child_pid
&& WIFSTOPPED (status
)
2626 && status
>> 16 == PTRACE_EVENT_FORK
)
2629 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
2630 if (ret
== 0 && second_pid
!= 0)
2634 linux_supports_tracefork_flag
= 1;
2635 my_waitpid (second_pid
, &second_status
, 0);
2636 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
2638 warning ("linux_test_for_tracefork: failed to kill second child");
2639 my_waitpid (second_pid
, &status
, 0);
2643 warning ("linux_test_for_tracefork: unexpected result from waitpid "
2644 "(%d, status 0x%x)", ret
, status
);
2648 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
2650 warning ("linux_test_for_tracefork: failed to kill child");
2651 my_waitpid (child_pid
, &status
, 0);
2653 while (WIFSTOPPED (status
));
2660 linux_look_up_symbols (void)
2662 #ifdef USE_THREAD_DB
2663 struct process_info
*proc
= current_process ();
2665 if (proc
->private->thread_db
!= NULL
)
2668 thread_db_init (!linux_supports_tracefork_flag
);
2673 linux_request_interrupt (void)
2675 extern unsigned long signal_pid
;
2677 if (!ptid_equal (cont_thread
, null_ptid
)
2678 && !ptid_equal (cont_thread
, minus_one_ptid
))
2680 struct lwp_info
*lwp
;
2683 lwp
= get_thread_lwp (current_inferior
);
2684 lwpid
= lwpid_of (lwp
);
2685 kill_lwp (lwpid
, SIGINT
);
2688 kill_lwp (signal_pid
, SIGINT
);
2691 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
2692 to debugger memory starting at MYADDR. */
2695 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
2697 char filename
[PATH_MAX
];
2699 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2701 snprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
2703 fd
= open (filename
, O_RDONLY
);
2707 if (offset
!= (CORE_ADDR
) 0
2708 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
2711 n
= read (fd
, myaddr
, len
);
2718 /* These breakpoint and watchpoint related wrapper functions simply
2719 pass on the function call if the target has registered a
2720 corresponding function. */
2723 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
2725 if (the_low_target
.insert_point
!= NULL
)
2726 return the_low_target
.insert_point (type
, addr
, len
);
2728 /* Unsupported (see target.h). */
2733 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
2735 if (the_low_target
.remove_point
!= NULL
)
2736 return the_low_target
.remove_point (type
, addr
, len
);
2738 /* Unsupported (see target.h). */
2743 linux_stopped_by_watchpoint (void)
2745 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2746 return the_low_target
.stopped_by_watchpoint ();
2752 linux_stopped_data_address (void)
2754 if (the_low_target
.stopped_data_address
!= NULL
)
2755 return the_low_target
.stopped_data_address ();
2760 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
2761 #if defined(__mcoldfire__)
2762 /* These should really be defined in the kernel's ptrace.h header. */
2763 #define PT_TEXT_ADDR 49*4
2764 #define PT_DATA_ADDR 50*4
2765 #define PT_TEXT_END_ADDR 51*4
2768 /* Under uClinux, programs are loaded at non-zero offsets, which we need
2769 to tell gdb about. */
2772 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
2774 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
2775 unsigned long text
, text_end
, data
;
2776 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2780 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
2781 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
2782 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
2786 /* Both text and data offsets produced at compile-time (and so
2787 used by gdb) are relative to the beginning of the program,
2788 with the data segment immediately following the text segment.
2789 However, the actual runtime layout in memory may put the data
2790 somewhere else, so when we send gdb a data base-address, we
2791 use the real data base address and subtract the compile-time
2792 data base-address from it (which is just the length of the
2793 text segment). BSS immediately follows data in both
2796 *data_p
= data
- (text_end
- text
);
2806 compare_ints (const void *xa
, const void *xb
)
2808 int a
= *(const int *)xa
;
2809 int b
= *(const int *)xb
;
2815 unique (int *b
, int *e
)
2824 /* Given PID, iterates over all threads in that process.
2826 Information about each thread, in a format suitable for qXfer:osdata:thread
2827 is printed to BUFFER, if it's not NULL. BUFFER is assumed to be already
2828 initialized, and the caller is responsible for finishing and appending '\0'
2831 The list of cores that threads are running on is assigned to *CORES, if it
2832 is not NULL. If no cores are found, *CORES will be set to NULL. Caller
2833 should free *CORES. */
2836 list_threads (int pid
, struct buffer
*buffer
, char **cores
)
2840 int *core_numbers
= xmalloc (sizeof (int) * allocated
);
2844 struct stat statbuf
;
2846 sprintf (pathname
, "/proc/%d/task", pid
);
2847 if (stat (pathname
, &statbuf
) == 0 && S_ISDIR (statbuf
.st_mode
))
2849 dir
= opendir (pathname
);
2852 free (core_numbers
);
2856 while ((dp
= readdir (dir
)) != NULL
)
2858 unsigned long lwp
= strtoul (dp
->d_name
, NULL
, 10);
2862 unsigned core
= linux_core_of_thread (ptid_build (pid
, lwp
, 0));
2866 char s
[sizeof ("4294967295")];
2867 sprintf (s
, "%u", core
);
2869 if (count
== allocated
)
2872 core_numbers
= realloc (core_numbers
,
2873 sizeof (int) * allocated
);
2875 core_numbers
[count
++] = core
;
2877 buffer_xml_printf (buffer
,
2879 "<column name=\"pid\">%d</column>"
2880 "<column name=\"tid\">%s</column>"
2881 "<column name=\"core\">%s</column>"
2882 "</item>", pid
, dp
->d_name
, s
);
2887 buffer_xml_printf (buffer
,
2889 "<column name=\"pid\">%d</column>"
2890 "<column name=\"tid\">%s</column>"
2891 "</item>", pid
, dp
->d_name
);
2902 struct buffer buffer2
;
2905 qsort (core_numbers
, count
, sizeof (int), compare_ints
);
2907 /* Remove duplicates. */
2909 e
= unique (b
, core_numbers
+ count
);
2911 buffer_init (&buffer2
);
2913 for (b
= core_numbers
; b
!= e
; ++b
)
2915 char number
[sizeof ("4294967295")];
2916 sprintf (number
, "%u", *b
);
2917 buffer_xml_printf (&buffer2
, "%s%s",
2918 (b
== core_numbers
) ? "" : ",", number
);
2920 buffer_grow_str0 (&buffer2
, "");
2922 *cores
= buffer_finish (&buffer2
);
2925 free (core_numbers
);
2929 show_process (int pid
, const char *username
, struct buffer
*buffer
)
2933 char cmd
[MAXPATHLEN
+ 1];
2935 sprintf (pathname
, "/proc/%d/cmdline", pid
);
2937 if ((f
= fopen (pathname
, "r")) != NULL
)
2939 size_t len
= fread (cmd
, 1, sizeof (cmd
) - 1, f
);
2944 for (i
= 0; i
< len
; i
++)
2949 buffer_xml_printf (buffer
,
2951 "<column name=\"pid\">%d</column>"
2952 "<column name=\"user\">%s</column>"
2953 "<column name=\"command\">%s</column>",
2958 /* This only collects core numbers, and does not print threads. */
2959 list_threads (pid
, NULL
, &cores
);
2963 buffer_xml_printf (buffer
,
2964 "<column name=\"cores\">%s</column>", cores
);
2968 buffer_xml_printf (buffer
, "</item>");
2975 linux_qxfer_osdata (const char *annex
,
2976 unsigned char *readbuf
, unsigned const char *writebuf
,
2977 CORE_ADDR offset
, int len
)
2979 /* We make the process list snapshot when the object starts to be
2981 static const char *buf
;
2982 static long len_avail
= -1;
2983 static struct buffer buffer
;
2989 if (strcmp (annex
, "processes") == 0)
2991 else if (strcmp (annex
, "threads") == 0)
2996 if (!readbuf
|| writebuf
)
3001 if (len_avail
!= -1 && len_avail
!= 0)
3002 buffer_free (&buffer
);
3005 buffer_init (&buffer
);
3007 buffer_grow_str (&buffer
, "<osdata type=\"processes\">");
3009 buffer_grow_str (&buffer
, "<osdata type=\"threads\">");
3011 dirp
= opendir ("/proc");
3015 while ((dp
= readdir (dirp
)) != NULL
)
3017 struct stat statbuf
;
3018 char procentry
[sizeof ("/proc/4294967295")];
3020 if (!isdigit (dp
->d_name
[0])
3021 || strlen (dp
->d_name
) > sizeof ("4294967295") - 1)
3024 sprintf (procentry
, "/proc/%s", dp
->d_name
);
3025 if (stat (procentry
, &statbuf
) == 0
3026 && S_ISDIR (statbuf
.st_mode
))
3028 int pid
= (int) strtoul (dp
->d_name
, NULL
, 10);
3032 struct passwd
*entry
= getpwuid (statbuf
.st_uid
);
3033 show_process (pid
, entry
? entry
->pw_name
: "?", &buffer
);
3037 list_threads (pid
, &buffer
, NULL
);
3044 buffer_grow_str0 (&buffer
, "</osdata>\n");
3045 buf
= buffer_finish (&buffer
);
3046 len_avail
= strlen (buf
);
3049 if (offset
>= len_avail
)
3051 /* Done. Get rid of the data. */
3052 buffer_free (&buffer
);
3058 if (len
> len_avail
- offset
)
3059 len
= len_avail
- offset
;
3060 memcpy (readbuf
, buf
+ offset
, len
);
3065 /* Convert a native/host siginfo object, into/from the siginfo in the
3066 layout of the inferiors' architecture. */
3069 siginfo_fixup (struct siginfo
*siginfo
, void *inf_siginfo
, int direction
)
3073 if (the_low_target
.siginfo_fixup
!= NULL
)
3074 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
3076 /* If there was no callback, or the callback didn't do anything,
3077 then just do a straight memcpy. */
3081 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
3083 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
3088 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
3089 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
3092 struct siginfo siginfo
;
3093 char inf_siginfo
[sizeof (struct siginfo
)];
3095 if (current_inferior
== NULL
)
3098 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3101 fprintf (stderr
, "%s siginfo for lwp %d.\n",
3102 readbuf
!= NULL
? "Reading" : "Writing",
3105 if (offset
> sizeof (siginfo
))
3108 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
3111 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
3112 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
3113 inferior with a 64-bit GDBSERVER should look the same as debugging it
3114 with a 32-bit GDBSERVER, we need to convert it. */
3115 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
3117 if (offset
+ len
> sizeof (siginfo
))
3118 len
= sizeof (siginfo
) - offset
;
3120 if (readbuf
!= NULL
)
3121 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
3124 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
3126 /* Convert back to ptrace layout before flushing it out. */
3127 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
3129 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
3136 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
3137 so we notice when children change state; as the handler for the
3138 sigsuspend in my_waitpid. */
3141 sigchld_handler (int signo
)
3143 int old_errno
= errno
;
3146 /* fprintf is not async-signal-safe, so call write directly. */
3147 write (2, "sigchld_handler\n", sizeof ("sigchld_handler\n") - 1);
3149 if (target_is_async_p ())
3150 async_file_mark (); /* trigger a linux_wait */
3156 linux_supports_non_stop (void)
3162 linux_async (int enable
)
3164 int previous
= (linux_event_pipe
[0] != -1);
3166 if (previous
!= enable
)
3169 sigemptyset (&mask
);
3170 sigaddset (&mask
, SIGCHLD
);
3172 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
3176 if (pipe (linux_event_pipe
) == -1)
3177 fatal ("creating event pipe failed.");
3179 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
3180 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
3182 /* Register the event loop handler. */
3183 add_file_handler (linux_event_pipe
[0],
3184 handle_target_event
, NULL
);
3186 /* Always trigger a linux_wait. */
3191 delete_file_handler (linux_event_pipe
[0]);
3193 close (linux_event_pipe
[0]);
3194 close (linux_event_pipe
[1]);
3195 linux_event_pipe
[0] = -1;
3196 linux_event_pipe
[1] = -1;
3199 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
3206 linux_start_non_stop (int nonstop
)
3208 /* Register or unregister from event-loop accordingly. */
3209 linux_async (nonstop
);
3214 linux_supports_multi_process (void)
3220 /* Enumerate spufs IDs for process PID. */
3222 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
3228 struct dirent
*entry
;
3230 sprintf (path
, "/proc/%ld/fd", pid
);
3231 dir
= opendir (path
);
3236 while ((entry
= readdir (dir
)) != NULL
)
3242 fd
= atoi (entry
->d_name
);
3246 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
3247 if (stat (path
, &st
) != 0)
3249 if (!S_ISDIR (st
.st_mode
))
3252 if (statfs (path
, &stfs
) != 0)
3254 if (stfs
.f_type
!= SPUFS_MAGIC
)
3257 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
3259 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
3269 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
3270 object type, using the /proc file system. */
3272 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
3273 unsigned const char *writebuf
,
3274 CORE_ADDR offset
, int len
)
3276 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
3281 if (!writebuf
&& !readbuf
)
3289 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
3292 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
3293 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
3298 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
3305 ret
= write (fd
, writebuf
, (size_t) len
);
3307 ret
= read (fd
, readbuf
, (size_t) len
);
3314 linux_core_of_thread (ptid_t ptid
)
3316 char filename
[sizeof ("/proc//task//stat")
3317 + 2 * 20 /* decimal digits for 2 numbers, max 2^64 bit each */
3320 char *content
= NULL
;
3323 int content_read
= 0;
3327 sprintf (filename
, "/proc/%d/task/%ld/stat",
3328 ptid_get_pid (ptid
), ptid_get_lwp (ptid
));
3329 f
= fopen (filename
, "r");
3336 content
= realloc (content
, content_read
+ 1024);
3337 n
= fread (content
+ content_read
, 1, 1024, f
);
3341 content
[content_read
] = '\0';
3346 p
= strchr (content
, '(');
3347 p
= strchr (p
, ')') + 2; /* skip ")" and a whitespace. */
3349 p
= strtok_r (p
, " ", &ts
);
3350 for (i
= 0; i
!= 36; ++i
)
3351 p
= strtok_r (NULL
, " ", &ts
);
3353 if (sscanf (p
, "%d", &core
) == 0)
3362 static struct target_ops linux_target_ops
= {
3363 linux_create_inferior
,
3371 linux_fetch_registers
,
3372 linux_store_registers
,
3375 linux_look_up_symbols
,
3376 linux_request_interrupt
,
3380 linux_stopped_by_watchpoint
,
3381 linux_stopped_data_address
,
3382 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
3387 #ifdef USE_THREAD_DB
3388 thread_db_get_tls_address
,
3393 hostio_last_error_from_errno
,
3396 linux_supports_non_stop
,
3398 linux_start_non_stop
,
3399 linux_supports_multi_process
,
3400 #ifdef USE_THREAD_DB
3401 thread_db_handle_monitor_command
,
3405 linux_core_of_thread
3409 linux_init_signals ()
3411 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
3412 to find what the cancel signal actually is. */
3413 signal (__SIGRTMIN
+1, SIG_IGN
);
3417 initialize_low (void)
3419 struct sigaction sigchld_action
;
3420 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
3421 set_target_ops (&linux_target_ops
);
3422 set_breakpoint_data (the_low_target
.breakpoint
,
3423 the_low_target
.breakpoint_len
);
3424 linux_init_signals ();
3425 linux_test_for_tracefork ();
3426 #ifdef HAVE_LINUX_REGSETS
3427 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
3429 disabled_regsets
= xmalloc (num_regsets
);
3432 sigchld_action
.sa_handler
= sigchld_handler
;
3433 sigemptyset (&sigchld_action
.sa_mask
);
3434 sigchld_action
.sa_flags
= SA_RESTART
;
3435 sigaction (SIGCHLD
, &sigchld_action
, NULL
);