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 void *add_lwp (ptid_t ptid
);
144 static int linux_stopped_by_watchpoint (void);
145 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
146 static int linux_core_of_thread (ptid_t ptid
);
147 static void proceed_all_lwps (void);
148 static void unstop_all_lwps (struct lwp_info
*except
);
149 static int finish_step_over (struct lwp_info
*lwp
);
150 static CORE_ADDR
get_stop_pc (struct lwp_info
*lwp
);
151 static int kill_lwp (unsigned long lwpid
, int signo
);
153 /* True if the low target can hardware single-step. Such targets
154 don't need a BREAKPOINT_REINSERT_ADDR callback. */
157 can_hardware_single_step (void)
159 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
162 /* True if the low target supports memory breakpoints. If so, we'll
163 have a GET_PC implementation. */
166 supports_breakpoints (void)
168 return (the_low_target
.get_pc
!= NULL
);
171 struct pending_signals
175 struct pending_signals
*prev
;
178 #define PTRACE_ARG3_TYPE void *
179 #define PTRACE_ARG4_TYPE void *
180 #define PTRACE_XFER_TYPE long
182 #ifdef HAVE_LINUX_REGSETS
183 static char *disabled_regsets
;
184 static int num_regsets
;
187 /* The read/write ends of the pipe registered as waitable file in the
189 static int linux_event_pipe
[2] = { -1, -1 };
191 /* True if we're currently in async mode. */
192 #define target_is_async_p() (linux_event_pipe[0] != -1)
194 static void send_sigstop (struct inferior_list_entry
*entry
);
195 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
197 /* Accepts an integer PID; Returns a string representing a file that
198 can be opened to get info for the child process.
199 Space for the result is malloc'd, caller must free. */
202 linux_child_pid_to_exec_file (int pid
)
206 name1
= xmalloc (MAXPATHLEN
);
207 name2
= xmalloc (MAXPATHLEN
);
208 memset (name2
, 0, MAXPATHLEN
);
210 sprintf (name1
, "/proc/%d/exe", pid
);
211 if (readlink (name1
, name2
, MAXPATHLEN
) > 0)
223 /* Return non-zero if HEADER is a 64-bit ELF file. */
226 elf_64_header_p (const Elf64_Ehdr
*header
)
228 return (header
->e_ident
[EI_MAG0
] == ELFMAG0
229 && header
->e_ident
[EI_MAG1
] == ELFMAG1
230 && header
->e_ident
[EI_MAG2
] == ELFMAG2
231 && header
->e_ident
[EI_MAG3
] == ELFMAG3
232 && header
->e_ident
[EI_CLASS
] == ELFCLASS64
);
235 /* Return non-zero if FILE is a 64-bit ELF file,
236 zero if the file is not a 64-bit ELF file,
237 and -1 if the file is not accessible or doesn't exist. */
240 elf_64_file_p (const char *file
)
245 fd
= open (file
, O_RDONLY
);
249 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
256 return elf_64_header_p (&header
);
260 delete_lwp (struct lwp_info
*lwp
)
262 remove_thread (get_lwp_thread (lwp
));
263 remove_inferior (&all_lwps
, &lwp
->head
);
264 free (lwp
->arch_private
);
268 /* Add a process to the common process list, and set its private
271 static struct process_info
*
272 linux_add_process (int pid
, int attached
)
274 struct process_info
*proc
;
276 /* Is this the first process? If so, then set the arch. */
277 if (all_processes
.head
== NULL
)
280 proc
= add_process (pid
, attached
);
281 proc
->private = xcalloc (1, sizeof (*proc
->private));
283 if (the_low_target
.new_process
!= NULL
)
284 proc
->private->arch_private
= the_low_target
.new_process ();
289 /* Remove a process from the common process list,
290 also freeing all private data. */
293 linux_remove_process (struct process_info
*process
)
295 struct process_info_private
*priv
= process
->private;
297 free (priv
->arch_private
);
299 remove_process (process
);
302 /* Wrapper function for waitpid which handles EINTR, and emulates
303 __WALL for systems where that is not available. */
306 my_waitpid (int pid
, int *status
, int flags
)
311 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
315 sigset_t block_mask
, org_mask
, wake_mask
;
318 wnohang
= (flags
& WNOHANG
) != 0;
319 flags
&= ~(__WALL
| __WCLONE
);
322 /* Block all signals while here. This avoids knowing about
323 LinuxThread's signals. */
324 sigfillset (&block_mask
);
325 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
327 /* ... except during the sigsuspend below. */
328 sigemptyset (&wake_mask
);
332 /* Since all signals are blocked, there's no need to check
334 ret
= waitpid (pid
, status
, flags
);
337 if (ret
== -1 && out_errno
!= ECHILD
)
342 if (flags
& __WCLONE
)
344 /* We've tried both flavors now. If WNOHANG is set,
345 there's nothing else to do, just bail out. */
350 fprintf (stderr
, "blocking\n");
352 /* Block waiting for signals. */
353 sigsuspend (&wake_mask
);
359 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
364 ret
= waitpid (pid
, status
, flags
);
365 while (ret
== -1 && errno
== EINTR
);
370 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
371 pid
, flags
, status
? *status
: -1, ret
);
377 /* Handle a GNU/Linux extended wait response. If we see a clone
378 event, we need to add the new LWP to our list (and not report the
379 trap to higher layers). */
382 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
384 int event
= wstat
>> 16;
385 struct lwp_info
*new_lwp
;
387 if (event
== PTRACE_EVENT_CLONE
)
390 unsigned long new_pid
;
391 int ret
, status
= W_STOPCODE (SIGSTOP
);
393 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), 0, &new_pid
);
395 /* If we haven't already seen the new PID stop, wait for it now. */
396 if (! pull_pid_from_list (&stopped_pids
, new_pid
))
398 /* The new child has a pending SIGSTOP. We can't affect it until it
399 hits the SIGSTOP, but we're already attached. */
401 ret
= my_waitpid (new_pid
, &status
, __WALL
);
404 perror_with_name ("waiting for new child");
405 else if (ret
!= new_pid
)
406 warning ("wait returned unexpected PID %d", ret
);
407 else if (!WIFSTOPPED (status
))
408 warning ("wait returned unexpected status 0x%x", status
);
411 ptrace (PTRACE_SETOPTIONS
, new_pid
, 0, (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
413 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
414 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
415 add_thread (ptid
, new_lwp
);
417 /* Either we're going to immediately resume the new thread
418 or leave it stopped. linux_resume_one_lwp is a nop if it
419 thinks the thread is currently running, so set this first
420 before calling linux_resume_one_lwp. */
421 new_lwp
->stopped
= 1;
423 /* Normally we will get the pending SIGSTOP. But in some cases
424 we might get another signal delivered to the group first.
425 If we do get another signal, be sure not to lose it. */
426 if (WSTOPSIG (status
) == SIGSTOP
)
428 if (stopping_threads
)
429 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
431 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
435 new_lwp
->stop_expected
= 1;
437 if (stopping_threads
)
439 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
440 new_lwp
->status_pending_p
= 1;
441 new_lwp
->status_pending
= status
;
444 /* Pass the signal on. This is what GDB does - except
445 shouldn't we really report it instead? */
446 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
449 /* Always resume the current thread. If we are stopping
450 threads, it will have a pending SIGSTOP; we may as well
452 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
456 /* Return the PC as read from the regcache of LWP, without any
460 get_pc (struct lwp_info
*lwp
)
462 struct thread_info
*saved_inferior
;
463 struct regcache
*regcache
;
466 if (the_low_target
.get_pc
== NULL
)
469 saved_inferior
= current_inferior
;
470 current_inferior
= get_lwp_thread (lwp
);
472 regcache
= get_thread_regcache (current_inferior
, 1);
473 pc
= (*the_low_target
.get_pc
) (regcache
);
476 fprintf (stderr
, "pc is 0x%lx\n", (long) pc
);
478 current_inferior
= saved_inferior
;
482 /* This function should only be called if LWP got a SIGTRAP.
483 The SIGTRAP could mean several things.
485 On i386, where decr_pc_after_break is non-zero:
486 If we were single-stepping this process using PTRACE_SINGLESTEP,
487 we will get only the one SIGTRAP (even if the instruction we
488 stepped over was a breakpoint). The value of $eip will be the
490 If we continue the process using PTRACE_CONT, we will get a
491 SIGTRAP when we hit a breakpoint. The value of $eip will be
492 the instruction after the breakpoint (i.e. needs to be
493 decremented). If we report the SIGTRAP to GDB, we must also
494 report the undecremented PC. If we cancel the SIGTRAP, we
495 must resume at the decremented PC.
497 (Presumably, not yet tested) On a non-decr_pc_after_break machine
498 with hardware or kernel single-step:
499 If we single-step over a breakpoint instruction, our PC will
500 point at the following instruction. If we continue and hit a
501 breakpoint instruction, our PC will point at the breakpoint
505 get_stop_pc (struct lwp_info
*lwp
)
509 if (the_low_target
.get_pc
== NULL
)
512 stop_pc
= get_pc (lwp
);
514 if (WSTOPSIG (lwp
->last_status
) == SIGTRAP
&& !lwp
->stepping
)
515 stop_pc
-= the_low_target
.decr_pc_after_break
;
518 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
524 add_lwp (ptid_t ptid
)
526 struct lwp_info
*lwp
;
528 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
529 memset (lwp
, 0, sizeof (*lwp
));
533 lwp
->last_resume_kind
= resume_continue
;
535 if (the_low_target
.new_thread
!= NULL
)
536 lwp
->arch_private
= the_low_target
.new_thread ();
538 add_inferior_to_list (&all_lwps
, &lwp
->head
);
543 /* Start an inferior process and returns its pid.
544 ALLARGS is a vector of program-name and args. */
547 linux_create_inferior (char *program
, char **allargs
)
549 struct lwp_info
*new_lwp
;
553 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
559 perror_with_name ("fork");
563 ptrace (PTRACE_TRACEME
, 0, 0, 0);
565 #ifdef __SIGRTMIN /* Bionic doesn't use SIGRTMIN the way glibc does. */
566 signal (__SIGRTMIN
+ 1, SIG_DFL
);
571 execv (program
, allargs
);
573 execvp (program
, allargs
);
575 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
581 linux_add_process (pid
, 0);
583 ptid
= ptid_build (pid
, pid
, 0);
584 new_lwp
= add_lwp (ptid
);
585 add_thread (ptid
, new_lwp
);
586 new_lwp
->must_set_ptrace_flags
= 1;
591 /* Attach to an inferior process. */
594 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
597 struct lwp_info
*new_lwp
;
599 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) != 0)
603 /* If we fail to attach to an LWP, just warn. */
604 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
605 strerror (errno
), errno
);
610 /* If we fail to attach to a process, report an error. */
611 error ("Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
612 strerror (errno
), errno
);
616 /* NOTE/FIXME: This lwp might have not been the tgid. */
617 ptid
= ptid_build (lwpid
, lwpid
, 0);
620 /* Note that extracting the pid from the current inferior is
621 safe, since we're always called in the context of the same
622 process as this new thread. */
623 int pid
= pid_of (get_thread_lwp (current_inferior
));
624 ptid
= ptid_build (pid
, lwpid
, 0);
627 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
628 add_thread (ptid
, new_lwp
);
630 /* We need to wait for SIGSTOP before being able to make the next
631 ptrace call on this LWP. */
632 new_lwp
->must_set_ptrace_flags
= 1;
634 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
637 There are several cases to consider here:
639 1) gdbserver has already attached to the process and is being notified
640 of a new thread that is being created.
641 In this case we should ignore that SIGSTOP and resume the
642 process. This is handled below by setting stop_expected = 1,
643 and the fact that add_lwp sets last_resume_kind ==
646 2) This is the first thread (the process thread), and we're attaching
647 to it via attach_inferior.
648 In this case we want the process thread to stop.
649 This is handled by having linux_attach set last_resume_kind ==
650 resume_stop after we return.
651 ??? If the process already has several threads we leave the other
654 3) GDB is connecting to gdbserver and is requesting an enumeration of all
656 In this case we want the thread to stop.
657 FIXME: This case is currently not properly handled.
658 We should wait for the SIGSTOP but don't. Things work apparently
659 because enough time passes between when we ptrace (ATTACH) and when
660 gdb makes the next ptrace call on the thread.
662 On the other hand, if we are currently trying to stop all threads, we
663 should treat the new thread as if we had sent it a SIGSTOP. This works
664 because we are guaranteed that the add_lwp call above added us to the
665 end of the list, and so the new thread has not yet reached
666 wait_for_sigstop (but will). */
667 new_lwp
->stop_expected
= 1;
671 linux_attach_lwp (unsigned long lwpid
)
673 linux_attach_lwp_1 (lwpid
, 0);
677 linux_attach (unsigned long pid
)
679 struct lwp_info
*lwp
;
681 linux_attach_lwp_1 (pid
, 1);
683 linux_add_process (pid
, 1);
687 /* Don't ignore the initial SIGSTOP if we just attached to this
688 process. It will be collected by wait shortly. */
689 lwp
= (struct lwp_info
*) find_inferior_id (&all_lwps
,
690 ptid_build (pid
, pid
, 0));
691 lwp
->last_resume_kind
= resume_stop
;
704 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
706 struct counter
*counter
= args
;
708 if (ptid_get_pid (entry
->id
) == counter
->pid
)
710 if (++counter
->count
> 1)
718 last_thread_of_process_p (struct thread_info
*thread
)
720 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
721 int pid
= ptid_get_pid (ptid
);
722 struct counter counter
= { pid
, 0 };
724 return (find_inferior (&all_threads
,
725 second_thread_of_pid_p
, &counter
) == NULL
);
728 /* Kill the inferior lwp. */
731 linux_kill_one_lwp (struct inferior_list_entry
*entry
, void *args
)
733 struct thread_info
*thread
= (struct thread_info
*) entry
;
734 struct lwp_info
*lwp
= get_thread_lwp (thread
);
736 int pid
= * (int *) args
;
738 if (ptid_get_pid (entry
->id
) != pid
)
741 /* We avoid killing the first thread here, because of a Linux kernel (at
742 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
743 the children get a chance to be reaped, it will remain a zombie
746 if (lwpid_of (lwp
) == pid
)
749 fprintf (stderr
, "lkop: is last of process %s\n",
750 target_pid_to_str (entry
->id
));
754 /* If we're killing a running inferior, make sure it is stopped
755 first, as PTRACE_KILL will not work otherwise. */
757 send_sigstop (&lwp
->head
);
761 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
763 /* Make sure it died. The loop is most likely unnecessary. */
764 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
765 } while (pid
> 0 && WIFSTOPPED (wstat
));
773 struct process_info
*process
;
774 struct lwp_info
*lwp
;
775 struct thread_info
*thread
;
779 process
= find_process_pid (pid
);
783 find_inferior (&all_threads
, linux_kill_one_lwp
, &pid
);
785 /* See the comment in linux_kill_one_lwp. We did not kill the first
786 thread in the list, so do so now. */
787 lwp
= find_lwp_pid (pid_to_ptid (pid
));
788 thread
= get_lwp_thread (lwp
);
791 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
792 lwpid_of (lwp
), pid
);
794 /* If we're killing a running inferior, make sure it is stopped
795 first, as PTRACE_KILL will not work otherwise. */
797 send_sigstop (&lwp
->head
);
801 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
803 /* Make sure it died. The loop is most likely unnecessary. */
804 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
805 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
808 thread_db_free (process
, 0);
811 linux_remove_process (process
);
816 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
818 struct thread_info
*thread
= (struct thread_info
*) entry
;
819 struct lwp_info
*lwp
= get_thread_lwp (thread
);
820 int pid
= * (int *) args
;
822 if (ptid_get_pid (entry
->id
) != pid
)
825 /* If we're detaching from a running inferior, make sure it is
826 stopped first, as PTRACE_DETACH will not work otherwise. */
829 int lwpid
= lwpid_of (lwp
);
831 stopping_threads
= 1;
832 send_sigstop (&lwp
->head
);
834 /* If this detects a new thread through a clone event, the new
835 thread is appended to the end of the lwp list, so we'll
836 eventually detach from it. */
837 wait_for_sigstop (&lwp
->head
);
838 stopping_threads
= 0;
840 /* If LWP exits while we're trying to stop it, there's nothing
842 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
847 /* If this process is stopped but is expecting a SIGSTOP, then make
848 sure we take care of that now. This isn't absolutely guaranteed
849 to collect the SIGSTOP, but is fairly likely to. */
850 if (lwp
->stop_expected
)
853 /* Clear stop_expected, so that the SIGSTOP will be reported. */
854 lwp
->stop_expected
= 0;
856 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
857 linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
860 /* Flush any pending changes to the process's registers. */
861 regcache_invalidate_one ((struct inferior_list_entry
*)
862 get_lwp_thread (lwp
));
864 /* Finally, let it resume. */
865 ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0, 0);
872 any_thread_of (struct inferior_list_entry
*entry
, void *args
)
876 if (ptid_get_pid (entry
->id
) == *pid_p
)
883 linux_detach (int pid
)
885 struct process_info
*process
;
887 process
= find_process_pid (pid
);
892 thread_db_free (process
, 1);
896 (struct thread_info
*) find_inferior (&all_threads
, any_thread_of
, &pid
);
898 delete_all_breakpoints ();
899 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
900 linux_remove_process (process
);
908 struct process_info
*process
;
910 process
= find_process_pid (pid
);
915 ret
= my_waitpid (pid
, &status
, 0);
916 if (WIFEXITED (status
) || WIFSIGNALED (status
))
918 } while (ret
!= -1 || errno
!= ECHILD
);
921 /* Return nonzero if the given thread is still alive. */
923 linux_thread_alive (ptid_t ptid
)
925 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
927 /* We assume we always know if a thread exits. If a whole process
928 exited but we still haven't been able to report it to GDB, we'll
929 hold on to the last lwp of the dead process. */
936 /* Return 1 if this lwp has an interesting status pending. */
938 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
940 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
941 ptid_t ptid
= * (ptid_t
*) arg
;
942 struct thread_info
*thread
= get_lwp_thread (lwp
);
944 /* Check if we're only interested in events from a specific process
946 if (!ptid_equal (minus_one_ptid
, ptid
)
947 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
950 thread
= get_lwp_thread (lwp
);
952 /* If we got a `vCont;t', but we haven't reported a stop yet, do
953 report any status pending the LWP may have. */
954 if (lwp
->last_resume_kind
== resume_stop
955 && thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
)
958 return lwp
->status_pending_p
;
962 same_lwp (struct inferior_list_entry
*entry
, void *data
)
964 ptid_t ptid
= *(ptid_t
*) data
;
967 if (ptid_get_lwp (ptid
) != 0)
968 lwp
= ptid_get_lwp (ptid
);
970 lwp
= ptid_get_pid (ptid
);
972 if (ptid_get_lwp (entry
->id
) == lwp
)
979 find_lwp_pid (ptid_t ptid
)
981 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
984 static struct lwp_info
*
985 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
988 int to_wait_for
= -1;
989 struct lwp_info
*child
= NULL
;
992 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
994 if (ptid_equal (ptid
, minus_one_ptid
))
995 to_wait_for
= -1; /* any child */
997 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1003 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1004 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1007 perror_with_name ("waitpid");
1010 && (!WIFSTOPPED (*wstatp
)
1011 || (WSTOPSIG (*wstatp
) != 32
1012 && WSTOPSIG (*wstatp
) != 33)))
1013 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1015 child
= find_lwp_pid (pid_to_ptid (ret
));
1017 /* If we didn't find a process, one of two things presumably happened:
1018 - A process we started and then detached from has exited. Ignore it.
1019 - A process we are controlling has forked and the new child's stop
1020 was reported to us by the kernel. Save its PID. */
1021 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1023 add_pid_to_list (&stopped_pids
, ret
);
1026 else if (child
== NULL
)
1031 child
->last_status
= *wstatp
;
1033 /* Architecture-specific setup after inferior is running.
1034 This needs to happen after we have attached to the inferior
1035 and it is stopped for the first time, but before we access
1036 any inferior registers. */
1039 the_low_target
.arch_setup ();
1040 #ifdef HAVE_LINUX_REGSETS
1041 memset (disabled_regsets
, 0, num_regsets
);
1046 /* Fetch the possibly triggered data watchpoint info and store it in
1049 On some archs, like x86, that use debug registers to set
1050 watchpoints, it's possible that the way to know which watched
1051 address trapped, is to check the register that is used to select
1052 which address to watch. Problem is, between setting the
1053 watchpoint and reading back which data address trapped, the user
1054 may change the set of watchpoints, and, as a consequence, GDB
1055 changes the debug registers in the inferior. To avoid reading
1056 back a stale stopped-data-address when that happens, we cache in
1057 LP the fact that a watchpoint trapped, and the corresponding data
1058 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1059 changes the debug registers meanwhile, we have the cached data we
1062 if (WIFSTOPPED (*wstatp
) && WSTOPSIG (*wstatp
) == SIGTRAP
)
1064 if (the_low_target
.stopped_by_watchpoint
== NULL
)
1066 child
->stopped_by_watchpoint
= 0;
1070 struct thread_info
*saved_inferior
;
1072 saved_inferior
= current_inferior
;
1073 current_inferior
= get_lwp_thread (child
);
1075 child
->stopped_by_watchpoint
1076 = the_low_target
.stopped_by_watchpoint ();
1078 if (child
->stopped_by_watchpoint
)
1080 if (the_low_target
.stopped_data_address
!= NULL
)
1081 child
->stopped_data_address
1082 = the_low_target
.stopped_data_address ();
1084 child
->stopped_data_address
= 0;
1087 current_inferior
= saved_inferior
;
1091 /* Store the STOP_PC, with adjustment applied. This depends on the
1092 architecture being defined already (so that CHILD has a valid
1093 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1095 if (WIFSTOPPED (*wstatp
))
1096 child
->stop_pc
= get_stop_pc (child
);
1099 && WIFSTOPPED (*wstatp
)
1100 && the_low_target
.get_pc
!= NULL
)
1102 struct thread_info
*saved_inferior
= current_inferior
;
1103 struct regcache
*regcache
;
1106 current_inferior
= get_lwp_thread (child
);
1107 regcache
= get_thread_regcache (current_inferior
, 1);
1108 pc
= (*the_low_target
.get_pc
) (regcache
);
1109 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1110 current_inferior
= saved_inferior
;
1116 /* Arrange for a breakpoint to be hit again later. We don't keep the
1117 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1118 will handle the current event, eventually we will resume this LWP,
1119 and this breakpoint will trap again. */
1122 cancel_breakpoint (struct lwp_info
*lwp
)
1124 struct thread_info
*saved_inferior
;
1125 struct regcache
*regcache
;
1127 /* There's nothing to do if we don't support breakpoints. */
1128 if (!supports_breakpoints ())
1135 "CB: [%s] is stepping\n",
1136 target_pid_to_str (lwp
->head
.id
));
1140 regcache
= get_thread_regcache (get_lwp_thread (lwp
), 1);
1142 /* breakpoint_at reads from current inferior. */
1143 saved_inferior
= current_inferior
;
1144 current_inferior
= get_lwp_thread (lwp
);
1146 if ((*the_low_target
.breakpoint_at
) (lwp
->stop_pc
))
1150 "CB: Push back breakpoint for %s\n",
1151 target_pid_to_str (lwp
->head
.id
));
1153 /* Back up the PC if necessary. */
1154 if (the_low_target
.decr_pc_after_break
)
1156 struct regcache
*regcache
1157 = get_thread_regcache (get_lwp_thread (lwp
), 1);
1158 (*the_low_target
.set_pc
) (regcache
, lwp
->stop_pc
);
1161 current_inferior
= saved_inferior
;
1168 "CB: No breakpoint found at %s for [%s]\n",
1169 paddress (lwp
->stop_pc
),
1170 target_pid_to_str (lwp
->head
.id
));
1173 current_inferior
= saved_inferior
;
1177 /* When the event-loop is doing a step-over, this points at the thread
1179 ptid_t step_over_bkpt
;
1181 /* Wait for an event from child PID. If PID is -1, wait for any
1182 child. Store the stop status through the status pointer WSTAT.
1183 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1184 event was found and OPTIONS contains WNOHANG. Return the PID of
1185 the stopped child otherwise. */
1188 linux_wait_for_event_1 (ptid_t ptid
, int *wstat
, int options
)
1190 struct lwp_info
*event_child
, *requested_child
;
1193 requested_child
= NULL
;
1195 /* Check for a lwp with a pending status. */
1197 if (ptid_equal (ptid
, minus_one_ptid
)
1198 || ptid_equal (pid_to_ptid (ptid_get_pid (ptid
)), ptid
))
1200 event_child
= (struct lwp_info
*)
1201 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1202 if (debug_threads
&& event_child
)
1203 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1207 requested_child
= find_lwp_pid (ptid
);
1209 if (requested_child
->status_pending_p
)
1210 event_child
= requested_child
;
1213 if (event_child
!= NULL
)
1216 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1217 lwpid_of (event_child
), event_child
->status_pending
);
1218 *wstat
= event_child
->status_pending
;
1219 event_child
->status_pending_p
= 0;
1220 event_child
->status_pending
= 0;
1221 current_inferior
= get_lwp_thread (event_child
);
1222 return lwpid_of (event_child
);
1225 /* We only enter this loop if no process has a pending wait status. Thus
1226 any action taken in response to a wait status inside this loop is
1227 responding as soon as we detect the status, not after any pending
1231 event_child
= linux_wait_for_lwp (ptid
, wstat
, options
);
1233 if ((options
& WNOHANG
) && event_child
== NULL
)
1236 fprintf (stderr
, "WNOHANG set, no event found\n");
1240 if (event_child
== NULL
)
1241 error ("event from unknown child");
1243 current_inferior
= get_lwp_thread (event_child
);
1245 /* Check for thread exit. */
1246 if (! WIFSTOPPED (*wstat
))
1249 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1251 /* If the last thread is exiting, just return. */
1252 if (last_thread_of_process_p (current_inferior
))
1255 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1256 lwpid_of (event_child
));
1257 return lwpid_of (event_child
);
1262 current_inferior
= (struct thread_info
*) all_threads
.head
;
1264 fprintf (stderr
, "Current inferior is now %ld\n",
1265 lwpid_of (get_thread_lwp (current_inferior
)));
1269 current_inferior
= NULL
;
1271 fprintf (stderr
, "Current inferior is now <NULL>\n");
1274 /* If we were waiting for this particular child to do something...
1275 well, it did something. */
1276 if (requested_child
!= NULL
)
1278 int lwpid
= lwpid_of (event_child
);
1280 /* Cancel the step-over operation --- the thread that
1281 started it is gone. */
1282 if (finish_step_over (event_child
))
1283 unstop_all_lwps (event_child
);
1284 delete_lwp (event_child
);
1288 delete_lwp (event_child
);
1290 /* Wait for a more interesting event. */
1294 if (event_child
->must_set_ptrace_flags
)
1296 ptrace (PTRACE_SETOPTIONS
, lwpid_of (event_child
),
1297 0, (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
1298 event_child
->must_set_ptrace_flags
= 0;
1301 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1302 && *wstat
>> 16 != 0)
1304 handle_extended_wait (event_child
, *wstat
);
1308 /* If GDB is not interested in this signal, don't stop other
1309 threads, and don't report it to GDB. Just resume the
1310 inferior right away. We do this for threading-related
1311 signals as well as any that GDB specifically requested we
1312 ignore. But never ignore SIGSTOP if we sent it ourselves,
1313 and do not ignore signals when stepping - they may require
1314 special handling to skip the signal handler. */
1315 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
1317 if (WIFSTOPPED (*wstat
)
1318 && !event_child
->stepping
1320 #if defined (USE_THREAD_DB) && defined (__SIGRTMIN)
1321 (current_process ()->private->thread_db
!= NULL
1322 && (WSTOPSIG (*wstat
) == __SIGRTMIN
1323 || WSTOPSIG (*wstat
) == __SIGRTMIN
+ 1))
1326 (pass_signals
[target_signal_from_host (WSTOPSIG (*wstat
))]
1327 && !(WSTOPSIG (*wstat
) == SIGSTOP
1328 && event_child
->stop_expected
))))
1330 siginfo_t info
, *info_p
;
1333 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
1334 WSTOPSIG (*wstat
), lwpid_of (event_child
));
1336 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
1340 linux_resume_one_lwp (event_child
, event_child
->stepping
,
1341 WSTOPSIG (*wstat
), info_p
);
1345 if (WIFSTOPPED (*wstat
)
1346 && WSTOPSIG (*wstat
) == SIGSTOP
1347 && event_child
->stop_expected
)
1352 fprintf (stderr
, "Expected stop.\n");
1353 event_child
->stop_expected
= 0;
1355 should_stop
= (event_child
->last_resume_kind
== resume_stop
1356 || stopping_threads
);
1360 linux_resume_one_lwp (event_child
,
1361 event_child
->stepping
, 0, NULL
);
1366 return lwpid_of (event_child
);
1374 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1378 if (ptid_is_pid (ptid
))
1380 /* A request to wait for a specific tgid. This is not possible
1381 with waitpid, so instead, we wait for any child, and leave
1382 children we're not interested in right now with a pending
1383 status to report later. */
1384 wait_ptid
= minus_one_ptid
;
1393 event_pid
= linux_wait_for_event_1 (wait_ptid
, wstat
, options
);
1396 && ptid_is_pid (ptid
) && ptid_get_pid (ptid
) != event_pid
)
1398 struct lwp_info
*event_child
= find_lwp_pid (pid_to_ptid (event_pid
));
1400 if (! WIFSTOPPED (*wstat
))
1401 mark_lwp_dead (event_child
, *wstat
);
1404 event_child
->status_pending_p
= 1;
1405 event_child
->status_pending
= *wstat
;
1414 /* Count the LWP's that have had events. */
1417 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
1419 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1422 gdb_assert (count
!= NULL
);
1424 /* Count only resumed LWPs that have a SIGTRAP event pending that
1425 should be reported to GDB. */
1426 if (get_lwp_thread (lp
)->last_status
.kind
== TARGET_WAITKIND_IGNORE
1427 && lp
->last_resume_kind
!= resume_stop
1428 && lp
->status_pending_p
1429 && WIFSTOPPED (lp
->status_pending
)
1430 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1431 && !breakpoint_inserted_here (lp
->stop_pc
))
1437 /* Select the LWP (if any) that is currently being single-stepped. */
1440 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1442 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1444 if (get_lwp_thread (lp
)->last_status
.kind
== TARGET_WAITKIND_IGNORE
1445 && lp
->last_resume_kind
== resume_step
1446 && lp
->status_pending_p
)
1452 /* Select the Nth LWP that has had a SIGTRAP event that should be
1456 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1458 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1459 int *selector
= data
;
1461 gdb_assert (selector
!= NULL
);
1463 /* Select only resumed LWPs that have a SIGTRAP event pending. */
1464 if (lp
->last_resume_kind
!= resume_stop
1465 && get_lwp_thread (lp
)->last_status
.kind
== TARGET_WAITKIND_IGNORE
1466 && lp
->status_pending_p
1467 && WIFSTOPPED (lp
->status_pending
)
1468 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1469 && !breakpoint_inserted_here (lp
->stop_pc
))
1470 if ((*selector
)-- == 0)
1477 cancel_breakpoints_callback (struct inferior_list_entry
*entry
, void *data
)
1479 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1480 struct lwp_info
*event_lp
= data
;
1482 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
1486 /* If a LWP other than the LWP that we're reporting an event for has
1487 hit a GDB breakpoint (as opposed to some random trap signal),
1488 then just arrange for it to hit it again later. We don't keep
1489 the SIGTRAP status and don't forward the SIGTRAP signal to the
1490 LWP. We will handle the current event, eventually we will resume
1491 all LWPs, and this one will get its breakpoint trap again.
1493 If we do not do this, then we run the risk that the user will
1494 delete or disable the breakpoint, but the LWP will have already
1497 if (lp
->last_resume_kind
!= resume_stop
1498 && get_lwp_thread (lp
)->last_status
.kind
== TARGET_WAITKIND_IGNORE
1499 && lp
->status_pending_p
1500 && WIFSTOPPED (lp
->status_pending
)
1501 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1502 && cancel_breakpoint (lp
))
1503 /* Throw away the SIGTRAP. */
1504 lp
->status_pending_p
= 0;
1509 /* Select one LWP out of those that have events pending. */
1512 select_event_lwp (struct lwp_info
**orig_lp
)
1515 int random_selector
;
1516 struct lwp_info
*event_lp
;
1518 /* Give preference to any LWP that is being single-stepped. */
1520 = (struct lwp_info
*) find_inferior (&all_lwps
,
1521 select_singlestep_lwp_callback
, NULL
);
1522 if (event_lp
!= NULL
)
1526 "SEL: Select single-step %s\n",
1527 target_pid_to_str (ptid_of (event_lp
)));
1531 /* No single-stepping LWP. Select one at random, out of those
1532 which have had SIGTRAP events. */
1534 /* First see how many SIGTRAP events we have. */
1535 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
1537 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
1538 random_selector
= (int)
1539 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
1541 if (debug_threads
&& num_events
> 1)
1543 "SEL: Found %d SIGTRAP events, selecting #%d\n",
1544 num_events
, random_selector
);
1546 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
1547 select_event_lwp_callback
,
1551 if (event_lp
!= NULL
)
1553 /* Switch the event LWP. */
1554 *orig_lp
= event_lp
;
1558 /* Set this inferior LWP's state as "want-stopped". We won't resume
1559 this LWP until the client gives us another action for it. */
1562 gdb_wants_lwp_stopped (struct inferior_list_entry
*entry
)
1564 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1565 struct thread_info
*thread
= get_lwp_thread (lwp
);
1567 /* Most threads are stopped implicitly (all-stop); tag that with
1568 signal 0. The thread being explicitly reported stopped to the
1569 client, gets it's status fixed up afterwards. */
1570 thread
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
1571 thread
->last_status
.value
.sig
= TARGET_SIGNAL_0
;
1573 lwp
->last_resume_kind
= resume_stop
;
1576 /* Set all LWP's states as "want-stopped". */
1579 gdb_wants_all_stopped (void)
1581 for_each_inferior (&all_lwps
, gdb_wants_lwp_stopped
);
1584 /* Wait for process, returns status. */
1587 linux_wait_1 (ptid_t ptid
,
1588 struct target_waitstatus
*ourstatus
, int target_options
)
1591 struct thread_info
*thread
= NULL
;
1592 struct lwp_info
*event_child
= NULL
;
1595 int step_over_finished
;
1596 int bp_explains_trap
;
1597 int maybe_internal_trap
;
1600 /* Translate generic target options into linux options. */
1602 if (target_options
& TARGET_WNOHANG
)
1606 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
1608 /* If we were only supposed to resume one thread, only wait for
1609 that thread - if it's still alive. If it died, however - which
1610 can happen if we're coming from the thread death case below -
1611 then we need to make sure we restart the other threads. We could
1612 pick a thread at random or restart all; restarting all is less
1615 && !ptid_equal (cont_thread
, null_ptid
)
1616 && !ptid_equal (cont_thread
, minus_one_ptid
))
1618 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
1621 /* No stepping, no signal - unless one is pending already, of course. */
1624 struct thread_resume resume_info
;
1625 resume_info
.thread
= minus_one_ptid
;
1626 resume_info
.kind
= resume_continue
;
1627 resume_info
.sig
= 0;
1628 linux_resume (&resume_info
, 1);
1634 if (ptid_equal (step_over_bkpt
, null_ptid
))
1635 pid
= linux_wait_for_event (ptid
, &w
, options
);
1639 fprintf (stderr
, "step_over_bkpt set [%s], doing a blocking wait\n",
1640 target_pid_to_str (step_over_bkpt
));
1641 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
1644 if (pid
== 0) /* only if TARGET_WNOHANG */
1647 event_child
= get_thread_lwp (current_inferior
);
1649 /* If we are waiting for a particular child, and it exited,
1650 linux_wait_for_event will return its exit status. Similarly if
1651 the last child exited. If this is not the last child, however,
1652 do not report it as exited until there is a 'thread exited' response
1653 available in the remote protocol. Instead, just wait for another event.
1654 This should be safe, because if the thread crashed we will already
1655 have reported the termination signal to GDB; that should stop any
1656 in-progress stepping operations, etc.
1658 Report the exit status of the last thread to exit. This matches
1659 LinuxThreads' behavior. */
1661 if (last_thread_of_process_p (current_inferior
))
1663 if (WIFEXITED (w
) || WIFSIGNALED (w
))
1665 int pid
= pid_of (event_child
);
1666 struct process_info
*process
= find_process_pid (pid
);
1668 #ifdef USE_THREAD_DB
1669 thread_db_free (process
, 0);
1671 delete_lwp (event_child
);
1672 linux_remove_process (process
);
1674 current_inferior
= NULL
;
1678 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
1679 ourstatus
->value
.integer
= WEXITSTATUS (w
);
1682 fprintf (stderr
, "\nChild exited with retcode = %x \n", WEXITSTATUS (w
));
1686 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
1687 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
1690 fprintf (stderr
, "\nChild terminated with signal = %x \n", WTERMSIG (w
));
1694 return pid_to_ptid (pid
);
1699 if (!WIFSTOPPED (w
))
1703 /* If this event was not handled before, and is not a SIGTRAP, we
1704 report it. SIGILL and SIGSEGV are also treated as traps in case
1705 a breakpoint is inserted at the current PC. If this target does
1706 not support internal breakpoints at all, we also report the
1707 SIGTRAP without further processing; it's of no concern to us. */
1709 = (supports_breakpoints ()
1710 && (WSTOPSIG (w
) == SIGTRAP
1711 || ((WSTOPSIG (w
) == SIGILL
1712 || WSTOPSIG (w
) == SIGSEGV
)
1713 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
1715 if (maybe_internal_trap
)
1717 /* Handle anything that requires bookkeeping before deciding to
1718 report the event or continue waiting. */
1720 /* First check if we can explain the SIGTRAP with an internal
1721 breakpoint, or if we should possibly report the event to GDB.
1722 Do this before anything that may remove or insert a
1724 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
1726 /* We have a SIGTRAP, possibly a step-over dance has just
1727 finished. If so, tweak the state machine accordingly,
1728 reinsert breakpoints and delete any reinsert (software
1729 single-step) breakpoints. */
1730 step_over_finished
= finish_step_over (event_child
);
1732 /* Now invoke the callbacks of any internal breakpoints there. */
1733 check_breakpoints (event_child
->stop_pc
);
1735 if (bp_explains_trap
)
1737 /* If we stepped or ran into an internal breakpoint, we've
1738 already handled it. So next time we resume (from this
1739 PC), we should step over it. */
1741 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
1743 event_child
->need_step_over
= 1;
1748 /* We have some other signal, possibly a step-over dance was in
1749 progress, and it should be cancelled too. */
1750 step_over_finished
= finish_step_over (event_child
);
1753 /* We have all the data we need. Either report the event to GDB, or
1754 resume threads and keep waiting for more. */
1756 /* Check If GDB would be interested in this event. If GDB wanted
1757 this thread to single step, we always want to report the SIGTRAP,
1758 and let GDB handle it. */
1759 report_to_gdb
= (!maybe_internal_trap
1760 || event_child
->last_resume_kind
== resume_step
1761 || event_child
->stopped_by_watchpoint
1762 || (!step_over_finished
&& !bp_explains_trap
));
1764 /* We found no reason GDB would want us to stop. We either hit one
1765 of our own breakpoints, or finished an internal step GDB
1766 shouldn't know about. */
1771 if (bp_explains_trap
)
1772 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
1773 if (step_over_finished
)
1774 fprintf (stderr
, "Step-over finished.\n");
1777 /* We're not reporting this breakpoint to GDB, so apply the
1778 decr_pc_after_break adjustment to the inferior's regcache
1781 if (the_low_target
.set_pc
!= NULL
)
1783 struct regcache
*regcache
1784 = get_thread_regcache (get_lwp_thread (event_child
), 1);
1785 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
1788 /* We've finished stepping over a breakpoint. We've stopped all
1789 LWPs momentarily except the stepping one. This is where we
1790 resume them all again. We're going to keep waiting, so use
1791 proceed, which handles stepping over the next breakpoint. */
1793 fprintf (stderr
, "proceeding all threads.\n");
1794 proceed_all_lwps ();
1800 if (event_child
->last_resume_kind
== resume_step
)
1801 fprintf (stderr
, "GDB wanted to single-step, reporting event.\n");
1802 if (event_child
->stopped_by_watchpoint
)
1803 fprintf (stderr
, "Stopped by watchpoint.\n");
1805 fprintf (stderr
, "Hit a non-gdbserver trap event.\n");
1808 /* Alright, we're going to report a stop. */
1812 /* In all-stop, stop all threads. */
1815 /* If we're not waiting for a specific LWP, choose an event LWP
1816 from among those that have had events. Giving equal priority
1817 to all LWPs that have had events helps prevent
1819 if (ptid_equal (ptid
, minus_one_ptid
))
1821 event_child
->status_pending_p
= 1;
1822 event_child
->status_pending
= w
;
1824 select_event_lwp (&event_child
);
1826 event_child
->status_pending_p
= 0;
1827 w
= event_child
->status_pending
;
1830 /* Now that we've selected our final event LWP, cancel any
1831 breakpoints in other LWPs that have hit a GDB breakpoint.
1832 See the comment in cancel_breakpoints_callback to find out
1834 find_inferior (&all_lwps
, cancel_breakpoints_callback
, event_child
);
1838 /* If we just finished a step-over, then all threads had been
1839 momentarily paused. In all-stop, that's fine, we want
1840 threads stopped by now anyway. In non-stop, we need to
1841 re-resume threads that GDB wanted to be running. */
1842 if (step_over_finished
)
1843 unstop_all_lwps (event_child
);
1846 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
1848 /* Do this before the gdb_wants_all_stopped calls below, since they
1849 always set last_resume_kind to resume_stop. */
1850 if (event_child
->last_resume_kind
== resume_stop
&& WSTOPSIG (w
) == SIGSTOP
)
1852 /* A thread that has been requested to stop by GDB with vCont;t,
1853 and it stopped cleanly, so report as SIG0. The use of
1854 SIGSTOP is an implementation detail. */
1855 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
1857 else if (event_child
->last_resume_kind
== resume_stop
&& WSTOPSIG (w
) != SIGSTOP
)
1859 /* A thread that has been requested to stop by GDB with vCont;t,
1860 but, it stopped for other reasons. */
1861 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
1865 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
1868 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
1872 /* From GDB's perspective, all-stop mode always stops all
1873 threads implicitly. Tag all threads as "want-stopped". */
1874 gdb_wants_all_stopped ();
1878 /* We're reporting this LWP as stopped. Update it's
1879 "want-stopped" state to what the client wants, until it gets
1880 a new resume action. */
1881 gdb_wants_lwp_stopped (&event_child
->head
);
1885 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
1886 target_pid_to_str (ptid_of (event_child
)),
1888 ourstatus
->value
.sig
);
1890 get_lwp_thread (event_child
)->last_status
= *ourstatus
;
1891 return ptid_of (event_child
);
1894 /* Get rid of any pending event in the pipe. */
1896 async_file_flush (void)
1902 ret
= read (linux_event_pipe
[0], &buf
, 1);
1903 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
1906 /* Put something in the pipe, so the event loop wakes up. */
1908 async_file_mark (void)
1912 async_file_flush ();
1915 ret
= write (linux_event_pipe
[1], "+", 1);
1916 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
1918 /* Ignore EAGAIN. If the pipe is full, the event loop will already
1919 be awakened anyway. */
1923 linux_wait (ptid_t ptid
,
1924 struct target_waitstatus
*ourstatus
, int target_options
)
1929 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
1931 /* Flush the async file first. */
1932 if (target_is_async_p ())
1933 async_file_flush ();
1935 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
1937 /* If at least one stop was reported, there may be more. A single
1938 SIGCHLD can signal more than one child stop. */
1939 if (target_is_async_p ()
1940 && (target_options
& TARGET_WNOHANG
) != 0
1941 && !ptid_equal (event_ptid
, null_ptid
))
1947 /* Send a signal to an LWP. */
1950 kill_lwp (unsigned long lwpid
, int signo
)
1952 /* Use tkill, if possible, in case we are using nptl threads. If tkill
1953 fails, then we are not using nptl threads and we should be using kill. */
1957 static int tkill_failed
;
1964 ret
= syscall (__NR_tkill
, lwpid
, signo
);
1965 if (errno
!= ENOSYS
)
1972 return kill (lwpid
, signo
);
1976 send_sigstop (struct inferior_list_entry
*entry
)
1978 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1984 pid
= lwpid_of (lwp
);
1986 /* If we already have a pending stop signal for this process, don't
1988 if (lwp
->stop_expected
)
1991 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
1997 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
1999 lwp
->stop_expected
= 1;
2000 kill_lwp (pid
, SIGSTOP
);
2004 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
2006 /* It's dead, really. */
2009 /* Store the exit status for later. */
2010 lwp
->status_pending_p
= 1;
2011 lwp
->status_pending
= wstat
;
2013 /* Prevent trying to stop it. */
2016 /* No further stops are expected from a dead lwp. */
2017 lwp
->stop_expected
= 0;
2021 wait_for_sigstop (struct inferior_list_entry
*entry
)
2023 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2024 struct thread_info
*saved_inferior
;
2033 fprintf (stderr
, "wait_for_sigstop: LWP %ld already stopped\n",
2038 saved_inferior
= current_inferior
;
2039 if (saved_inferior
!= NULL
)
2040 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
2042 saved_tid
= null_ptid
; /* avoid bogus unused warning */
2044 ptid
= lwp
->head
.id
;
2047 fprintf (stderr
, "wait_for_sigstop: pulling one event\n");
2049 pid
= linux_wait_for_event (ptid
, &wstat
, __WALL
);
2051 /* If we stopped with a non-SIGSTOP signal, save it for later
2052 and record the pending SIGSTOP. If the process exited, just
2054 if (WIFSTOPPED (wstat
))
2057 fprintf (stderr
, "LWP %ld stopped with signal %d\n",
2058 lwpid_of (lwp
), WSTOPSIG (wstat
));
2060 if (WSTOPSIG (wstat
) != SIGSTOP
)
2063 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
2064 lwpid_of (lwp
), wstat
);
2066 lwp
->status_pending_p
= 1;
2067 lwp
->status_pending
= wstat
;
2073 fprintf (stderr
, "Process %d exited while stopping LWPs\n", pid
);
2075 lwp
= find_lwp_pid (pid_to_ptid (pid
));
2078 /* Leave this status pending for the next time we're able to
2079 report it. In the mean time, we'll report this lwp as
2080 dead to GDB, so GDB doesn't try to read registers and
2081 memory from it. This can only happen if this was the
2082 last thread of the process; otherwise, PID is removed
2083 from the thread tables before linux_wait_for_event
2085 mark_lwp_dead (lwp
, wstat
);
2089 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
2090 current_inferior
= saved_inferior
;
2094 fprintf (stderr
, "Previously current thread died.\n");
2098 /* We can't change the current inferior behind GDB's back,
2099 otherwise, a subsequent command may apply to the wrong
2101 current_inferior
= NULL
;
2105 /* Set a valid thread as current. */
2106 set_desired_inferior (0);
2112 stop_all_lwps (void)
2114 stopping_threads
= 1;
2115 for_each_inferior (&all_lwps
, send_sigstop
);
2116 for_each_inferior (&all_lwps
, wait_for_sigstop
);
2117 stopping_threads
= 0;
2120 /* Resume execution of the inferior process.
2121 If STEP is nonzero, single-step it.
2122 If SIGNAL is nonzero, give it that signal. */
2125 linux_resume_one_lwp (struct lwp_info
*lwp
,
2126 int step
, int signal
, siginfo_t
*info
)
2128 struct thread_info
*saved_inferior
;
2130 if (lwp
->stopped
== 0)
2133 /* If we have pending signals or status, and a new signal, enqueue the
2134 signal. Also enqueue the signal if we are waiting to reinsert a
2135 breakpoint; it will be picked up again below. */
2137 && (lwp
->status_pending_p
|| lwp
->pending_signals
!= NULL
2138 || lwp
->bp_reinsert
!= 0))
2140 struct pending_signals
*p_sig
;
2141 p_sig
= xmalloc (sizeof (*p_sig
));
2142 p_sig
->prev
= lwp
->pending_signals
;
2143 p_sig
->signal
= signal
;
2145 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
2147 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
2148 lwp
->pending_signals
= p_sig
;
2151 if (lwp
->status_pending_p
)
2154 fprintf (stderr
, "Not resuming lwp %ld (%s, signal %d, stop %s);"
2155 " has pending status\n",
2156 lwpid_of (lwp
), step
? "step" : "continue", signal
,
2157 lwp
->stop_expected
? "expected" : "not expected");
2161 saved_inferior
= current_inferior
;
2162 current_inferior
= get_lwp_thread (lwp
);
2165 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
2166 lwpid_of (lwp
), step
? "step" : "continue", signal
,
2167 lwp
->stop_expected
? "expected" : "not expected");
2169 /* This bit needs some thinking about. If we get a signal that
2170 we must report while a single-step reinsert is still pending,
2171 we often end up resuming the thread. It might be better to
2172 (ew) allow a stack of pending events; then we could be sure that
2173 the reinsert happened right away and not lose any signals.
2175 Making this stack would also shrink the window in which breakpoints are
2176 uninserted (see comment in linux_wait_for_lwp) but not enough for
2177 complete correctness, so it won't solve that problem. It may be
2178 worthwhile just to solve this one, however. */
2179 if (lwp
->bp_reinsert
!= 0)
2182 fprintf (stderr
, " pending reinsert at 0x%s\n",
2183 paddress (lwp
->bp_reinsert
));
2185 if (lwp
->bp_reinsert
!= 0 && can_hardware_single_step ())
2188 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
2193 /* Postpone any pending signal. It was enqueued above. */
2197 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
2199 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
2200 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
2201 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
2204 /* If we have pending signals, consume one unless we are trying to reinsert
2206 if (lwp
->pending_signals
!= NULL
&& lwp
->bp_reinsert
== 0)
2208 struct pending_signals
**p_sig
;
2210 p_sig
= &lwp
->pending_signals
;
2211 while ((*p_sig
)->prev
!= NULL
)
2212 p_sig
= &(*p_sig
)->prev
;
2214 signal
= (*p_sig
)->signal
;
2215 if ((*p_sig
)->info
.si_signo
!= 0)
2216 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
2222 if (the_low_target
.prepare_to_resume
!= NULL
)
2223 the_low_target
.prepare_to_resume (lwp
);
2225 regcache_invalidate_one ((struct inferior_list_entry
*)
2226 get_lwp_thread (lwp
));
2229 lwp
->stopped_by_watchpoint
= 0;
2230 lwp
->stepping
= step
;
2231 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0,
2232 /* Coerce to a uintptr_t first to avoid potential gcc warning
2233 of coercing an 8 byte integer to a 4 byte pointer. */
2234 (PTRACE_ARG4_TYPE
) (uintptr_t) signal
);
2236 current_inferior
= saved_inferior
;
2239 /* ESRCH from ptrace either means that the thread was already
2240 running (an error) or that it is gone (a race condition). If
2241 it's gone, we will get a notification the next time we wait,
2242 so we can ignore the error. We could differentiate these
2243 two, but it's tricky without waiting; the thread still exists
2244 as a zombie, so sending it signal 0 would succeed. So just
2249 perror_with_name ("ptrace");
2253 struct thread_resume_array
2255 struct thread_resume
*resume
;
2259 /* This function is called once per thread. We look up the thread
2260 in RESUME_PTR, and mark the thread with a pointer to the appropriate
2263 This algorithm is O(threads * resume elements), but resume elements
2264 is small (and will remain small at least until GDB supports thread
2267 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
2269 struct lwp_info
*lwp
;
2270 struct thread_info
*thread
;
2272 struct thread_resume_array
*r
;
2274 thread
= (struct thread_info
*) entry
;
2275 lwp
= get_thread_lwp (thread
);
2278 for (ndx
= 0; ndx
< r
->n
; ndx
++)
2280 ptid_t ptid
= r
->resume
[ndx
].thread
;
2281 if (ptid_equal (ptid
, minus_one_ptid
)
2282 || ptid_equal (ptid
, entry
->id
)
2283 || (ptid_is_pid (ptid
)
2284 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
2285 || (ptid_get_lwp (ptid
) == -1
2286 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
2288 if (r
->resume
[ndx
].kind
== resume_stop
2289 && lwp
->last_resume_kind
== resume_stop
)
2292 fprintf (stderr
, "already %s LWP %ld at GDB's request\n",
2293 thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
2301 lwp
->resume
= &r
->resume
[ndx
];
2302 lwp
->last_resume_kind
= lwp
->resume
->kind
;
2307 /* No resume action for this thread. */
2314 /* Set *FLAG_P if this lwp has an interesting status pending. */
2316 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
2318 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2320 /* LWPs which will not be resumed are not interesting, because
2321 we might not wait for them next time through linux_wait. */
2322 if (lwp
->resume
== NULL
)
2325 if (lwp
->status_pending_p
)
2326 * (int *) flag_p
= 1;
2331 /* Return 1 if this lwp that GDB wants running is stopped at an
2332 internal breakpoint that we need to step over. It assumes that any
2333 required STOP_PC adjustment has already been propagated to the
2334 inferior's regcache. */
2337 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
2339 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2340 struct thread_info
*saved_inferior
;
2343 /* LWPs which will not be resumed are not interesting, because we
2344 might not wait for them next time through linux_wait. */
2350 "Need step over [LWP %ld]? Ignoring, not stopped\n",
2355 if (lwp
->last_resume_kind
== resume_stop
)
2359 "Need step over [LWP %ld]? Ignoring, should remain stopped\n",
2364 if (!lwp
->need_step_over
)
2368 "Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
2371 if (lwp
->status_pending_p
)
2375 "Need step over [LWP %ld]? Ignoring, has pending status.\n",
2380 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
2384 /* If the PC has changed since we stopped, then don't do anything,
2385 and let the breakpoint/tracepoint be hit. This happens if, for
2386 instance, GDB handled the decr_pc_after_break subtraction itself,
2387 GDB is OOL stepping this thread, or the user has issued a "jump"
2388 command, or poked thread's registers herself. */
2389 if (pc
!= lwp
->stop_pc
)
2393 "Need step over [LWP %ld]? Cancelling, PC was changed. "
2394 "Old stop_pc was 0x%s, PC is now 0x%s\n",
2395 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
2397 lwp
->need_step_over
= 0;
2401 saved_inferior
= current_inferior
;
2402 current_inferior
= get_lwp_thread (lwp
);
2404 /* We only step over our breakpoints. */
2405 if (breakpoint_here (pc
))
2409 "Need step over [LWP %ld]? yes, found breakpoint at 0x%s\n",
2410 lwpid_of (lwp
), paddress (pc
));
2412 /* We've found an lwp that needs stepping over --- return 1 so
2413 that find_inferior stops looking. */
2414 current_inferior
= saved_inferior
;
2416 /* If the step over is cancelled, this is set again. */
2417 lwp
->need_step_over
= 0;
2421 current_inferior
= saved_inferior
;
2425 "Need step over [LWP %ld]? No, no breakpoint found at 0x%s\n",
2426 lwpid_of (lwp
), paddress (pc
));
2431 /* Start a step-over operation on LWP. When LWP stopped at a
2432 breakpoint, to make progress, we need to remove the breakpoint out
2433 of the way. If we let other threads run while we do that, they may
2434 pass by the breakpoint location and miss hitting it. To avoid
2435 that, a step-over momentarily stops all threads while LWP is
2436 single-stepped while the breakpoint is temporarily uninserted from
2437 the inferior. When the single-step finishes, we reinsert the
2438 breakpoint, and let all threads that are supposed to be running,
2441 On targets that don't support hardware single-step, we don't
2442 currently support full software single-stepping. Instead, we only
2443 support stepping over the thread event breakpoint, by asking the
2444 low target where to place a reinsert breakpoint. Since this
2445 routine assumes the breakpoint being stepped over is a thread event
2446 breakpoint, it usually assumes the return address of the current
2447 function is a good enough place to set the reinsert breakpoint. */
2450 start_step_over (struct lwp_info
*lwp
)
2452 struct thread_info
*saved_inferior
;
2458 "Starting step-over on LWP %ld. Stopping all threads\n",
2464 fprintf (stderr
, "Done stopping all threads for step-over.\n");
2466 /* Note, we should always reach here with an already adjusted PC,
2467 either by GDB (if we're resuming due to GDB's request), or by our
2468 caller, if we just finished handling an internal breakpoint GDB
2469 shouldn't care about. */
2472 saved_inferior
= current_inferior
;
2473 current_inferior
= get_lwp_thread (lwp
);
2475 lwp
->bp_reinsert
= pc
;
2476 uninsert_breakpoints_at (pc
);
2478 if (can_hardware_single_step ())
2484 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
2485 set_reinsert_breakpoint (raddr
);
2489 current_inferior
= saved_inferior
;
2491 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
2493 /* Require next event from this LWP. */
2494 step_over_bkpt
= lwp
->head
.id
;
2498 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
2499 start_step_over, if still there, and delete any reinsert
2500 breakpoints we've set, on non hardware single-step targets. */
2503 finish_step_over (struct lwp_info
*lwp
)
2505 if (lwp
->bp_reinsert
!= 0)
2508 fprintf (stderr
, "Finished step over.\n");
2510 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
2511 may be no breakpoint to reinsert there by now. */
2512 reinsert_breakpoints_at (lwp
->bp_reinsert
);
2514 lwp
->bp_reinsert
= 0;
2516 /* Delete any software-single-step reinsert breakpoints. No
2517 longer needed. We don't have to worry about other threads
2518 hitting this trap, and later not being able to explain it,
2519 because we were stepping over a breakpoint, and we hold all
2520 threads but LWP stopped while doing that. */
2521 if (!can_hardware_single_step ())
2522 delete_reinsert_breakpoints ();
2524 step_over_bkpt
= null_ptid
;
2531 /* This function is called once per thread. We check the thread's resume
2532 request, which will tell us whether to resume, step, or leave the thread
2533 stopped; and what signal, if any, it should be sent.
2535 For threads which we aren't explicitly told otherwise, we preserve
2536 the stepping flag; this is used for stepping over gdbserver-placed
2539 If pending_flags was set in any thread, we queue any needed
2540 signals, since we won't actually resume. We already have a pending
2541 event to report, so we don't need to preserve any step requests;
2542 they should be re-issued if necessary. */
2545 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
2547 struct lwp_info
*lwp
;
2548 struct thread_info
*thread
;
2550 int leave_all_stopped
= * (int *) arg
;
2553 thread
= (struct thread_info
*) entry
;
2554 lwp
= get_thread_lwp (thread
);
2556 if (lwp
->resume
== NULL
)
2559 if (lwp
->resume
->kind
== resume_stop
)
2562 fprintf (stderr
, "resume_stop request for LWP %ld\n", lwpid_of (lwp
));
2567 fprintf (stderr
, "stopping LWP %ld\n", lwpid_of (lwp
));
2569 /* Stop the thread, and wait for the event asynchronously,
2570 through the event loop. */
2571 send_sigstop (&lwp
->head
);
2576 fprintf (stderr
, "already stopped LWP %ld\n",
2579 /* The LWP may have been stopped in an internal event that
2580 was not meant to be notified back to GDB (e.g., gdbserver
2581 breakpoint), so we should be reporting a stop event in
2584 /* If the thread already has a pending SIGSTOP, this is a
2585 no-op. Otherwise, something later will presumably resume
2586 the thread and this will cause it to cancel any pending
2587 operation, due to last_resume_kind == resume_stop. If
2588 the thread already has a pending status to report, we
2589 will still report it the next time we wait - see
2590 status_pending_p_callback. */
2591 send_sigstop (&lwp
->head
);
2594 /* For stop requests, we're done. */
2596 get_lwp_thread (lwp
)->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
2600 /* If this thread which is about to be resumed has a pending status,
2601 then don't resume any threads - we can just report the pending
2602 status. Make sure to queue any signals that would otherwise be
2603 sent. In all-stop mode, we do this decision based on if *any*
2604 thread has a pending status. If there's a thread that needs the
2605 step-over-breakpoint dance, then don't resume any other thread
2606 but that particular one. */
2607 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
2612 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
2614 step
= (lwp
->resume
->kind
== resume_step
);
2615 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
2616 get_lwp_thread (lwp
)->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
2621 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
2623 /* If we have a new signal, enqueue the signal. */
2624 if (lwp
->resume
->sig
!= 0)
2626 struct pending_signals
*p_sig
;
2627 p_sig
= xmalloc (sizeof (*p_sig
));
2628 p_sig
->prev
= lwp
->pending_signals
;
2629 p_sig
->signal
= lwp
->resume
->sig
;
2630 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
2632 /* If this is the same signal we were previously stopped by,
2633 make sure to queue its siginfo. We can ignore the return
2634 value of ptrace; if it fails, we'll skip
2635 PTRACE_SETSIGINFO. */
2636 if (WIFSTOPPED (lwp
->last_status
)
2637 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
2638 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
2640 lwp
->pending_signals
= p_sig
;
2649 linux_resume (struct thread_resume
*resume_info
, size_t n
)
2651 struct thread_resume_array array
= { resume_info
, n
};
2652 struct lwp_info
*need_step_over
= NULL
;
2654 int leave_all_stopped
;
2656 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
2658 /* If there is a thread which would otherwise be resumed, which has
2659 a pending status, then don't resume any threads - we can just
2660 report the pending status. Make sure to queue any signals that
2661 would otherwise be sent. In non-stop mode, we'll apply this
2662 logic to each thread individually. We consume all pending events
2663 before considering to start a step-over (in all-stop). */
2666 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
2668 /* If there is a thread which would otherwise be resumed, which is
2669 stopped at a breakpoint that needs stepping over, then don't
2670 resume any threads - have it step over the breakpoint with all
2671 other threads stopped, then resume all threads again. Make sure
2672 to queue any signals that would otherwise be delivered or
2674 if (!any_pending
&& supports_breakpoints ())
2676 = (struct lwp_info
*) find_inferior (&all_lwps
,
2677 need_step_over_p
, NULL
);
2679 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
2683 if (need_step_over
!= NULL
)
2684 fprintf (stderr
, "Not resuming all, need step over\n");
2685 else if (any_pending
)
2687 "Not resuming, all-stop and found "
2688 "an LWP with pending status\n");
2690 fprintf (stderr
, "Resuming, no pending status or step over needed\n");
2693 /* Even if we're leaving threads stopped, queue all signals we'd
2694 otherwise deliver. */
2695 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
2698 start_step_over (need_step_over
);
2701 /* This function is called once per thread. We check the thread's
2702 last resume request, which will tell us whether to resume, step, or
2703 leave the thread stopped. Any signal the client requested to be
2704 delivered has already been enqueued at this point.
2706 If any thread that GDB wants running is stopped at an internal
2707 breakpoint that needs stepping over, we start a step-over operation
2708 on that particular thread, and leave all others stopped. */
2711 proceed_one_lwp (struct inferior_list_entry
*entry
)
2713 struct lwp_info
*lwp
;
2716 lwp
= (struct lwp_info
*) entry
;
2720 "proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
2725 fprintf (stderr
, " LWP %ld already running\n", lwpid_of (lwp
));
2729 if (lwp
->last_resume_kind
== resume_stop
)
2732 fprintf (stderr
, " client wants LWP %ld stopped\n", lwpid_of (lwp
));
2736 if (lwp
->status_pending_p
)
2739 fprintf (stderr
, " LWP %ld has pending status, leaving stopped\n",
2747 fprintf (stderr
, " LWP %ld is suspended\n", lwpid_of (lwp
));
2751 step
= lwp
->last_resume_kind
== resume_step
;
2752 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
2755 /* When we finish a step-over, set threads running again. If there's
2756 another thread that may need a step-over, now's the time to start
2757 it. Eventually, we'll move all threads past their breakpoints. */
2760 proceed_all_lwps (void)
2762 struct lwp_info
*need_step_over
;
2764 /* If there is a thread which would otherwise be resumed, which is
2765 stopped at a breakpoint that needs stepping over, then don't
2766 resume any threads - have it step over the breakpoint with all
2767 other threads stopped, then resume all threads again. */
2769 if (supports_breakpoints ())
2772 = (struct lwp_info
*) find_inferior (&all_lwps
,
2773 need_step_over_p
, NULL
);
2775 if (need_step_over
!= NULL
)
2778 fprintf (stderr
, "proceed_all_lwps: found "
2779 "thread %ld needing a step-over\n",
2780 lwpid_of (need_step_over
));
2782 start_step_over (need_step_over
);
2788 fprintf (stderr
, "Proceeding, no step-over needed\n");
2790 for_each_inferior (&all_lwps
, proceed_one_lwp
);
2793 /* Stopped LWPs that the client wanted to be running, that don't have
2794 pending statuses, are set to run again, except for EXCEPT, if not
2795 NULL. This undoes a stop_all_lwps call. */
2798 unstop_all_lwps (struct lwp_info
*except
)
2804 "unstopping all lwps, except=(LWP %ld)\n", lwpid_of (except
));
2807 "unstopping all lwps\n");
2810 /* Make sure proceed_one_lwp doesn't try to resume this thread. */
2812 ++except
->suspended
;
2814 for_each_inferior (&all_lwps
, proceed_one_lwp
);
2817 --except
->suspended
;
2820 #ifdef HAVE_LINUX_USRREGS
2823 register_addr (int regnum
)
2827 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
2828 error ("Invalid register number %d.", regnum
);
2830 addr
= the_low_target
.regmap
[regnum
];
2835 /* Fetch one register. */
2837 fetch_register (struct regcache
*regcache
, int regno
)
2844 if (regno
>= the_low_target
.num_regs
)
2846 if ((*the_low_target
.cannot_fetch_register
) (regno
))
2849 regaddr
= register_addr (regno
);
2853 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2854 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2855 & - sizeof (PTRACE_XFER_TYPE
));
2856 buf
= alloca (size
);
2857 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
2860 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
2861 ptrace (PTRACE_PEEKUSER
, pid
,
2862 /* Coerce to a uintptr_t first to avoid potential gcc warning
2863 of coercing an 8 byte integer to a 4 byte pointer. */
2864 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
, 0);
2865 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
2867 error ("reading register %d: %s", regno
, strerror (errno
));
2870 if (the_low_target
.supply_ptrace_register
)
2871 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
2873 supply_register (regcache
, regno
, buf
);
2876 /* Fetch all registers, or just one, from the child process. */
2878 usr_fetch_inferior_registers (struct regcache
*regcache
, int regno
)
2881 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
2882 fetch_register (regcache
, regno
);
2884 fetch_register (regcache
, regno
);
2887 /* Store our register values back into the inferior.
2888 If REGNO is -1, do this for all registers.
2889 Otherwise, REGNO specifies which register (so we can save time). */
2891 usr_store_inferior_registers (struct regcache
*regcache
, int regno
)
2900 if (regno
>= the_low_target
.num_regs
)
2903 if ((*the_low_target
.cannot_store_register
) (regno
) == 1)
2906 regaddr
= register_addr (regno
);
2910 size
= (register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2911 & - sizeof (PTRACE_XFER_TYPE
);
2912 buf
= alloca (size
);
2913 memset (buf
, 0, size
);
2915 if (the_low_target
.collect_ptrace_register
)
2916 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
2918 collect_register (regcache
, regno
, buf
);
2920 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2921 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
2924 ptrace (PTRACE_POKEUSER
, pid
,
2925 /* Coerce to a uintptr_t first to avoid potential gcc warning
2926 about coercing an 8 byte integer to a 4 byte pointer. */
2927 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
,
2928 (PTRACE_ARG4_TYPE
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
2931 /* At this point, ESRCH should mean the process is
2932 already gone, in which case we simply ignore attempts
2933 to change its registers. See also the related
2934 comment in linux_resume_one_lwp. */
2938 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
2939 error ("writing register %d: %s", regno
, strerror (errno
));
2941 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
2945 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
2946 usr_store_inferior_registers (regcache
, regno
);
2948 #endif /* HAVE_LINUX_USRREGS */
2952 #ifdef HAVE_LINUX_REGSETS
2955 regsets_fetch_inferior_registers (struct regcache
*regcache
)
2957 struct regset_info
*regset
;
2958 int saw_general_regs
= 0;
2961 regset
= target_regsets
;
2963 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2964 while (regset
->size
>= 0)
2969 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
2975 buf
= xmalloc (regset
->size
);
2977 res
= ptrace (regset
->get_request
, pid
, 0, buf
);
2979 res
= ptrace (regset
->get_request
, pid
, buf
, 0);
2985 /* If we get EIO on a regset, do not try it again for
2987 disabled_regsets
[regset
- target_regsets
] = 1;
2994 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
2999 else if (regset
->type
== GENERAL_REGS
)
3000 saw_general_regs
= 1;
3001 regset
->store_function (regcache
, buf
);
3005 if (saw_general_regs
)
3012 regsets_store_inferior_registers (struct regcache
*regcache
)
3014 struct regset_info
*regset
;
3015 int saw_general_regs
= 0;
3018 regset
= target_regsets
;
3020 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3021 while (regset
->size
>= 0)
3026 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
3032 buf
= xmalloc (regset
->size
);
3034 /* First fill the buffer with the current register set contents,
3035 in case there are any items in the kernel's regset that are
3036 not in gdbserver's regcache. */
3038 res
= ptrace (regset
->get_request
, pid
, 0, buf
);
3040 res
= ptrace (regset
->get_request
, pid
, buf
, 0);
3045 /* Then overlay our cached registers on that. */
3046 regset
->fill_function (regcache
, buf
);
3048 /* Only now do we write the register set. */
3050 res
= ptrace (regset
->set_request
, pid
, 0, buf
);
3052 res
= ptrace (regset
->set_request
, pid
, buf
, 0);
3060 /* If we get EIO on a regset, do not try it again for
3062 disabled_regsets
[regset
- target_regsets
] = 1;
3066 else if (errno
== ESRCH
)
3068 /* At this point, ESRCH should mean the process is
3069 already gone, in which case we simply ignore attempts
3070 to change its registers. See also the related
3071 comment in linux_resume_one_lwp. */
3077 perror ("Warning: ptrace(regsets_store_inferior_registers)");
3080 else if (regset
->type
== GENERAL_REGS
)
3081 saw_general_regs
= 1;
3085 if (saw_general_regs
)
3092 #endif /* HAVE_LINUX_REGSETS */
3096 linux_fetch_registers (struct regcache
*regcache
, int regno
)
3098 #ifdef HAVE_LINUX_REGSETS
3099 if (regsets_fetch_inferior_registers (regcache
) == 0)
3102 #ifdef HAVE_LINUX_USRREGS
3103 usr_fetch_inferior_registers (regcache
, regno
);
3108 linux_store_registers (struct regcache
*regcache
, int regno
)
3110 #ifdef HAVE_LINUX_REGSETS
3111 if (regsets_store_inferior_registers (regcache
) == 0)
3114 #ifdef HAVE_LINUX_USRREGS
3115 usr_store_inferior_registers (regcache
, regno
);
3120 /* Copy LEN bytes from inferior's memory starting at MEMADDR
3121 to debugger memory starting at MYADDR. */
3124 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
3127 /* Round starting address down to longword boundary. */
3128 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
3129 /* Round ending address up; get number of longwords that makes. */
3131 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
3132 / sizeof (PTRACE_XFER_TYPE
);
3133 /* Allocate buffer of that many longwords. */
3134 register PTRACE_XFER_TYPE
*buffer
3135 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
3138 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
3140 /* Try using /proc. Don't bother for one word. */
3141 if (len
>= 3 * sizeof (long))
3143 /* We could keep this file open and cache it - possibly one per
3144 thread. That requires some juggling, but is even faster. */
3145 sprintf (filename
, "/proc/%d/mem", pid
);
3146 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
3150 /* If pread64 is available, use it. It's faster if the kernel
3151 supports it (only one syscall), and it's 64-bit safe even on
3152 32-bit platforms (for instance, SPARC debugging a SPARC64
3155 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
3157 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, myaddr
, len
) != len
)
3169 /* Read all the longwords */
3170 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
3173 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
3174 about coercing an 8 byte integer to a 4 byte pointer. */
3175 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
3176 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
3181 /* Copy appropriate bytes out of the buffer. */
3183 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
3189 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
3190 memory at MEMADDR. On failure (cannot write to the inferior)
3191 returns the value of errno. */
3194 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
3197 /* Round starting address down to longword boundary. */
3198 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
3199 /* Round ending address up; get number of longwords that makes. */
3201 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1) / sizeof (PTRACE_XFER_TYPE
);
3202 /* Allocate buffer of that many longwords. */
3203 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
3204 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
3208 /* Dump up to four bytes. */
3209 unsigned int val
= * (unsigned int *) myaddr
;
3215 val
= val
& 0xffffff;
3216 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
3217 val
, (long)memaddr
);
3220 /* Fill start and end extra bytes of buffer with existing memory data. */
3223 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
3224 about coercing an 8 byte integer to a 4 byte pointer. */
3225 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
3226 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
3234 = ptrace (PTRACE_PEEKTEXT
, pid
,
3235 /* Coerce to a uintptr_t first to avoid potential gcc warning
3236 about coercing an 8 byte integer to a 4 byte pointer. */
3237 (PTRACE_ARG3_TYPE
) (uintptr_t) (addr
+ (count
- 1)
3238 * sizeof (PTRACE_XFER_TYPE
)),
3244 /* Copy data to be written over corresponding part of buffer. */
3246 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)), myaddr
, len
);
3248 /* Write the entire buffer. */
3250 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
3253 ptrace (PTRACE_POKETEXT
, pid
,
3254 /* Coerce to a uintptr_t first to avoid potential gcc warning
3255 about coercing an 8 byte integer to a 4 byte pointer. */
3256 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
3257 (PTRACE_ARG4_TYPE
) buffer
[i
]);
3265 /* Non-zero if the kernel supports PTRACE_O_TRACEFORK. */
3266 static int linux_supports_tracefork_flag
;
3268 /* Helper functions for linux_test_for_tracefork, called via clone (). */
3271 linux_tracefork_grandchild (void *arg
)
3276 #define STACK_SIZE 4096
3279 linux_tracefork_child (void *arg
)
3281 ptrace (PTRACE_TRACEME
, 0, 0, 0);
3282 kill (getpid (), SIGSTOP
);
3284 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
3287 linux_tracefork_grandchild (NULL
);
3289 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
3292 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
3293 CLONE_VM
| SIGCHLD
, NULL
);
3295 clone (linux_tracefork_grandchild
, arg
+ STACK_SIZE
,
3296 CLONE_VM
| SIGCHLD
, NULL
);
3299 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
3304 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
3305 sure that we can enable the option, and that it had the desired
3309 linux_test_for_tracefork (void)
3311 int child_pid
, ret
, status
;
3313 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
3314 char *stack
= xmalloc (STACK_SIZE
* 4);
3315 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
3317 linux_supports_tracefork_flag
= 0;
3319 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
3321 child_pid
= fork ();
3323 linux_tracefork_child (NULL
);
3325 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
3327 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
3329 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
3330 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
3331 #else /* !__ia64__ */
3332 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
3333 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
3334 #endif /* !__ia64__ */
3336 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
3338 if (child_pid
== -1)
3339 perror_with_name ("clone");
3341 ret
= my_waitpid (child_pid
, &status
, 0);
3343 perror_with_name ("waitpid");
3344 else if (ret
!= child_pid
)
3345 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
3346 if (! WIFSTOPPED (status
))
3347 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
3349 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
3350 (PTRACE_ARG4_TYPE
) PTRACE_O_TRACEFORK
);
3353 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
3356 warning ("linux_test_for_tracefork: failed to kill child");
3360 ret
= my_waitpid (child_pid
, &status
, 0);
3361 if (ret
!= child_pid
)
3362 warning ("linux_test_for_tracefork: failed to wait for killed child");
3363 else if (!WIFSIGNALED (status
))
3364 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
3365 "killed child", status
);
3370 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
3372 warning ("linux_test_for_tracefork: failed to resume child");
3374 ret
= my_waitpid (child_pid
, &status
, 0);
3376 if (ret
== child_pid
&& WIFSTOPPED (status
)
3377 && status
>> 16 == PTRACE_EVENT_FORK
)
3380 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
3381 if (ret
== 0 && second_pid
!= 0)
3385 linux_supports_tracefork_flag
= 1;
3386 my_waitpid (second_pid
, &second_status
, 0);
3387 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
3389 warning ("linux_test_for_tracefork: failed to kill second child");
3390 my_waitpid (second_pid
, &status
, 0);
3394 warning ("linux_test_for_tracefork: unexpected result from waitpid "
3395 "(%d, status 0x%x)", ret
, status
);
3399 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
3401 warning ("linux_test_for_tracefork: failed to kill child");
3402 my_waitpid (child_pid
, &status
, 0);
3404 while (WIFSTOPPED (status
));
3406 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
3408 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
3413 linux_look_up_symbols (void)
3415 #ifdef USE_THREAD_DB
3416 struct process_info
*proc
= current_process ();
3418 if (proc
->private->thread_db
!= NULL
)
3421 /* If the kernel supports tracing forks then it also supports tracing
3422 clones, and then we don't need to use the magic thread event breakpoint
3423 to learn about threads. */
3424 thread_db_init (!linux_supports_tracefork_flag
);
3429 linux_request_interrupt (void)
3431 extern unsigned long signal_pid
;
3433 if (!ptid_equal (cont_thread
, null_ptid
)
3434 && !ptid_equal (cont_thread
, minus_one_ptid
))
3436 struct lwp_info
*lwp
;
3439 lwp
= get_thread_lwp (current_inferior
);
3440 lwpid
= lwpid_of (lwp
);
3441 kill_lwp (lwpid
, SIGINT
);
3444 kill_lwp (signal_pid
, SIGINT
);
3447 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
3448 to debugger memory starting at MYADDR. */
3451 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
3453 char filename
[PATH_MAX
];
3455 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
3457 snprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
3459 fd
= open (filename
, O_RDONLY
);
3463 if (offset
!= (CORE_ADDR
) 0
3464 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
3467 n
= read (fd
, myaddr
, len
);
3474 /* These breakpoint and watchpoint related wrapper functions simply
3475 pass on the function call if the target has registered a
3476 corresponding function. */
3479 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
3481 if (the_low_target
.insert_point
!= NULL
)
3482 return the_low_target
.insert_point (type
, addr
, len
);
3484 /* Unsupported (see target.h). */
3489 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
3491 if (the_low_target
.remove_point
!= NULL
)
3492 return the_low_target
.remove_point (type
, addr
, len
);
3494 /* Unsupported (see target.h). */
3499 linux_stopped_by_watchpoint (void)
3501 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
3503 return lwp
->stopped_by_watchpoint
;
3507 linux_stopped_data_address (void)
3509 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
3511 return lwp
->stopped_data_address
;
3514 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
3515 #if defined(__mcoldfire__)
3516 /* These should really be defined in the kernel's ptrace.h header. */
3517 #define PT_TEXT_ADDR 49*4
3518 #define PT_DATA_ADDR 50*4
3519 #define PT_TEXT_END_ADDR 51*4
3522 /* Under uClinux, programs are loaded at non-zero offsets, which we need
3523 to tell gdb about. */
3526 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
3528 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
3529 unsigned long text
, text_end
, data
;
3530 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
3534 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
3535 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
3536 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
3540 /* Both text and data offsets produced at compile-time (and so
3541 used by gdb) are relative to the beginning of the program,
3542 with the data segment immediately following the text segment.
3543 However, the actual runtime layout in memory may put the data
3544 somewhere else, so when we send gdb a data base-address, we
3545 use the real data base address and subtract the compile-time
3546 data base-address from it (which is just the length of the
3547 text segment). BSS immediately follows data in both
3550 *data_p
= data
- (text_end
- text
);
3560 compare_ints (const void *xa
, const void *xb
)
3562 int a
= *(const int *)xa
;
3563 int b
= *(const int *)xb
;
3569 unique (int *b
, int *e
)
3578 /* Given PID, iterates over all threads in that process.
3580 Information about each thread, in a format suitable for qXfer:osdata:thread
3581 is printed to BUFFER, if it's not NULL. BUFFER is assumed to be already
3582 initialized, and the caller is responsible for finishing and appending '\0'
3585 The list of cores that threads are running on is assigned to *CORES, if it
3586 is not NULL. If no cores are found, *CORES will be set to NULL. Caller
3587 should free *CORES. */
3590 list_threads (int pid
, struct buffer
*buffer
, char **cores
)
3594 int *core_numbers
= xmalloc (sizeof (int) * allocated
);
3598 struct stat statbuf
;
3600 sprintf (pathname
, "/proc/%d/task", pid
);
3601 if (stat (pathname
, &statbuf
) == 0 && S_ISDIR (statbuf
.st_mode
))
3603 dir
= opendir (pathname
);
3606 free (core_numbers
);
3610 while ((dp
= readdir (dir
)) != NULL
)
3612 unsigned long lwp
= strtoul (dp
->d_name
, NULL
, 10);
3616 unsigned core
= linux_core_of_thread (ptid_build (pid
, lwp
, 0));
3620 char s
[sizeof ("4294967295")];
3621 sprintf (s
, "%u", core
);
3623 if (count
== allocated
)
3626 core_numbers
= realloc (core_numbers
,
3627 sizeof (int) * allocated
);
3629 core_numbers
[count
++] = core
;
3631 buffer_xml_printf (buffer
,
3633 "<column name=\"pid\">%d</column>"
3634 "<column name=\"tid\">%s</column>"
3635 "<column name=\"core\">%s</column>"
3636 "</item>", pid
, dp
->d_name
, s
);
3641 buffer_xml_printf (buffer
,
3643 "<column name=\"pid\">%d</column>"
3644 "<column name=\"tid\">%s</column>"
3645 "</item>", pid
, dp
->d_name
);
3656 struct buffer buffer2
;
3659 qsort (core_numbers
, count
, sizeof (int), compare_ints
);
3661 /* Remove duplicates. */
3663 e
= unique (b
, core_numbers
+ count
);
3665 buffer_init (&buffer2
);
3667 for (b
= core_numbers
; b
!= e
; ++b
)
3669 char number
[sizeof ("4294967295")];
3670 sprintf (number
, "%u", *b
);
3671 buffer_xml_printf (&buffer2
, "%s%s",
3672 (b
== core_numbers
) ? "" : ",", number
);
3674 buffer_grow_str0 (&buffer2
, "");
3676 *cores
= buffer_finish (&buffer2
);
3679 free (core_numbers
);
3683 show_process (int pid
, const char *username
, struct buffer
*buffer
)
3687 char cmd
[MAXPATHLEN
+ 1];
3689 sprintf (pathname
, "/proc/%d/cmdline", pid
);
3691 if ((f
= fopen (pathname
, "r")) != NULL
)
3693 size_t len
= fread (cmd
, 1, sizeof (cmd
) - 1, f
);
3698 for (i
= 0; i
< len
; i
++)
3703 buffer_xml_printf (buffer
,
3705 "<column name=\"pid\">%d</column>"
3706 "<column name=\"user\">%s</column>"
3707 "<column name=\"command\">%s</column>",
3712 /* This only collects core numbers, and does not print threads. */
3713 list_threads (pid
, NULL
, &cores
);
3717 buffer_xml_printf (buffer
,
3718 "<column name=\"cores\">%s</column>", cores
);
3722 buffer_xml_printf (buffer
, "</item>");
3729 linux_qxfer_osdata (const char *annex
,
3730 unsigned char *readbuf
, unsigned const char *writebuf
,
3731 CORE_ADDR offset
, int len
)
3733 /* We make the process list snapshot when the object starts to be
3735 static const char *buf
;
3736 static long len_avail
= -1;
3737 static struct buffer buffer
;
3743 if (strcmp (annex
, "processes") == 0)
3745 else if (strcmp (annex
, "threads") == 0)
3750 if (!readbuf
|| writebuf
)
3755 if (len_avail
!= -1 && len_avail
!= 0)
3756 buffer_free (&buffer
);
3759 buffer_init (&buffer
);
3761 buffer_grow_str (&buffer
, "<osdata type=\"processes\">");
3763 buffer_grow_str (&buffer
, "<osdata type=\"threads\">");
3765 dirp
= opendir ("/proc");
3769 while ((dp
= readdir (dirp
)) != NULL
)
3771 struct stat statbuf
;
3772 char procentry
[sizeof ("/proc/4294967295")];
3774 if (!isdigit (dp
->d_name
[0])
3775 || strlen (dp
->d_name
) > sizeof ("4294967295") - 1)
3778 sprintf (procentry
, "/proc/%s", dp
->d_name
);
3779 if (stat (procentry
, &statbuf
) == 0
3780 && S_ISDIR (statbuf
.st_mode
))
3782 int pid
= (int) strtoul (dp
->d_name
, NULL
, 10);
3786 struct passwd
*entry
= getpwuid (statbuf
.st_uid
);
3787 show_process (pid
, entry
? entry
->pw_name
: "?", &buffer
);
3791 list_threads (pid
, &buffer
, NULL
);
3798 buffer_grow_str0 (&buffer
, "</osdata>\n");
3799 buf
= buffer_finish (&buffer
);
3800 len_avail
= strlen (buf
);
3803 if (offset
>= len_avail
)
3805 /* Done. Get rid of the data. */
3806 buffer_free (&buffer
);
3812 if (len
> len_avail
- offset
)
3813 len
= len_avail
- offset
;
3814 memcpy (readbuf
, buf
+ offset
, len
);
3819 /* Convert a native/host siginfo object, into/from the siginfo in the
3820 layout of the inferiors' architecture. */
3823 siginfo_fixup (struct siginfo
*siginfo
, void *inf_siginfo
, int direction
)
3827 if (the_low_target
.siginfo_fixup
!= NULL
)
3828 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
3830 /* If there was no callback, or the callback didn't do anything,
3831 then just do a straight memcpy. */
3835 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
3837 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
3842 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
3843 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
3846 struct siginfo siginfo
;
3847 char inf_siginfo
[sizeof (struct siginfo
)];
3849 if (current_inferior
== NULL
)
3852 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3855 fprintf (stderr
, "%s siginfo for lwp %d.\n",
3856 readbuf
!= NULL
? "Reading" : "Writing",
3859 if (offset
> sizeof (siginfo
))
3862 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
3865 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
3866 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
3867 inferior with a 64-bit GDBSERVER should look the same as debugging it
3868 with a 32-bit GDBSERVER, we need to convert it. */
3869 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
3871 if (offset
+ len
> sizeof (siginfo
))
3872 len
= sizeof (siginfo
) - offset
;
3874 if (readbuf
!= NULL
)
3875 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
3878 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
3880 /* Convert back to ptrace layout before flushing it out. */
3881 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
3883 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
3890 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
3891 so we notice when children change state; as the handler for the
3892 sigsuspend in my_waitpid. */
3895 sigchld_handler (int signo
)
3897 int old_errno
= errno
;
3900 /* fprintf is not async-signal-safe, so call write directly. */
3901 write (2, "sigchld_handler\n", sizeof ("sigchld_handler\n") - 1);
3903 if (target_is_async_p ())
3904 async_file_mark (); /* trigger a linux_wait */
3910 linux_supports_non_stop (void)
3916 linux_async (int enable
)
3918 int previous
= (linux_event_pipe
[0] != -1);
3920 if (previous
!= enable
)
3923 sigemptyset (&mask
);
3924 sigaddset (&mask
, SIGCHLD
);
3926 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
3930 if (pipe (linux_event_pipe
) == -1)
3931 fatal ("creating event pipe failed.");
3933 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
3934 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
3936 /* Register the event loop handler. */
3937 add_file_handler (linux_event_pipe
[0],
3938 handle_target_event
, NULL
);
3940 /* Always trigger a linux_wait. */
3945 delete_file_handler (linux_event_pipe
[0]);
3947 close (linux_event_pipe
[0]);
3948 close (linux_event_pipe
[1]);
3949 linux_event_pipe
[0] = -1;
3950 linux_event_pipe
[1] = -1;
3953 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
3960 linux_start_non_stop (int nonstop
)
3962 /* Register or unregister from event-loop accordingly. */
3963 linux_async (nonstop
);
3968 linux_supports_multi_process (void)
3974 /* Enumerate spufs IDs for process PID. */
3976 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
3982 struct dirent
*entry
;
3984 sprintf (path
, "/proc/%ld/fd", pid
);
3985 dir
= opendir (path
);
3990 while ((entry
= readdir (dir
)) != NULL
)
3996 fd
= atoi (entry
->d_name
);
4000 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
4001 if (stat (path
, &st
) != 0)
4003 if (!S_ISDIR (st
.st_mode
))
4006 if (statfs (path
, &stfs
) != 0)
4008 if (stfs
.f_type
!= SPUFS_MAGIC
)
4011 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
4013 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
4023 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
4024 object type, using the /proc file system. */
4026 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
4027 unsigned const char *writebuf
,
4028 CORE_ADDR offset
, int len
)
4030 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
4035 if (!writebuf
&& !readbuf
)
4043 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
4046 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
4047 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
4052 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4059 ret
= write (fd
, writebuf
, (size_t) len
);
4061 ret
= read (fd
, readbuf
, (size_t) len
);
4068 linux_core_of_thread (ptid_t ptid
)
4070 char filename
[sizeof ("/proc//task//stat")
4071 + 2 * 20 /* decimal digits for 2 numbers, max 2^64 bit each */
4074 char *content
= NULL
;
4077 int content_read
= 0;
4081 sprintf (filename
, "/proc/%d/task/%ld/stat",
4082 ptid_get_pid (ptid
), ptid_get_lwp (ptid
));
4083 f
= fopen (filename
, "r");
4090 content
= realloc (content
, content_read
+ 1024);
4091 n
= fread (content
+ content_read
, 1, 1024, f
);
4095 content
[content_read
] = '\0';
4100 p
= strchr (content
, '(');
4101 p
= strchr (p
, ')') + 2; /* skip ")" and a whitespace. */
4103 p
= strtok_r (p
, " ", &ts
);
4104 for (i
= 0; i
!= 36; ++i
)
4105 p
= strtok_r (NULL
, " ", &ts
);
4107 if (sscanf (p
, "%d", &core
) == 0)
4116 static struct target_ops linux_target_ops
= {
4117 linux_create_inferior
,
4125 linux_fetch_registers
,
4126 linux_store_registers
,
4129 linux_look_up_symbols
,
4130 linux_request_interrupt
,
4134 linux_stopped_by_watchpoint
,
4135 linux_stopped_data_address
,
4136 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4141 #ifdef USE_THREAD_DB
4142 thread_db_get_tls_address
,
4147 hostio_last_error_from_errno
,
4150 linux_supports_non_stop
,
4152 linux_start_non_stop
,
4153 linux_supports_multi_process
,
4154 #ifdef USE_THREAD_DB
4155 thread_db_handle_monitor_command
,
4159 linux_core_of_thread
4163 linux_init_signals ()
4165 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
4166 to find what the cancel signal actually is. */
4167 #ifdef __SIGRTMIN /* Bionic doesn't use SIGRTMIN the way glibc does. */
4168 signal (__SIGRTMIN
+1, SIG_IGN
);
4173 initialize_low (void)
4175 struct sigaction sigchld_action
;
4176 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
4177 set_target_ops (&linux_target_ops
);
4178 set_breakpoint_data (the_low_target
.breakpoint
,
4179 the_low_target
.breakpoint_len
);
4180 linux_init_signals ();
4181 linux_test_for_tracefork ();
4182 #ifdef HAVE_LINUX_REGSETS
4183 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
4185 disabled_regsets
= xmalloc (num_regsets
);
4188 sigchld_action
.sa_handler
= sigchld_handler
;
4189 sigemptyset (&sigchld_action
.sa_mask
);
4190 sigchld_action
.sa_flags
= SA_RESTART
;
4191 sigaction (SIGCHLD
, &sigchld_action
, NULL
);