1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995, 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
3 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 #include "linux-low.h"
22 #include "ansidecl.h" /* For ATTRIBUTE_PACKED, must be bug in external.h. */
23 #include "elf/common.h"
24 #include "elf/external.h"
28 #include <sys/param.h>
29 #include <sys/ptrace.h>
31 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
47 #define SPUFS_MAGIC 0x23c9b64e
50 #ifndef PTRACE_GETSIGINFO
51 # define PTRACE_GETSIGINFO 0x4202
52 # define PTRACE_SETSIGINFO 0x4203
59 /* If the system headers did not provide the constants, hard-code the normal
61 #ifndef PTRACE_EVENT_FORK
63 #define PTRACE_SETOPTIONS 0x4200
64 #define PTRACE_GETEVENTMSG 0x4201
66 /* options set using PTRACE_SETOPTIONS */
67 #define PTRACE_O_TRACESYSGOOD 0x00000001
68 #define PTRACE_O_TRACEFORK 0x00000002
69 #define PTRACE_O_TRACEVFORK 0x00000004
70 #define PTRACE_O_TRACECLONE 0x00000008
71 #define PTRACE_O_TRACEEXEC 0x00000010
72 #define PTRACE_O_TRACEVFORKDONE 0x00000020
73 #define PTRACE_O_TRACEEXIT 0x00000040
75 /* Wait extended result codes for the above trace options. */
76 #define PTRACE_EVENT_FORK 1
77 #define PTRACE_EVENT_VFORK 2
78 #define PTRACE_EVENT_CLONE 3
79 #define PTRACE_EVENT_EXEC 4
80 #define PTRACE_EVENT_VFORK_DONE 5
81 #define PTRACE_EVENT_EXIT 6
83 #endif /* PTRACE_EVENT_FORK */
85 /* We can't always assume that this flag is available, but all systems
86 with the ptrace event handlers also have __WALL, so it's safe to use
89 #define __WALL 0x40000000 /* Wait for any child. */
93 #if !(defined(__UCLIBC_HAS_MMU__) || defined(__ARCH_HAS_MMU__))
98 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
99 representation of the thread ID.
101 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
102 the same as the LWP ID.
104 ``all_processes'' is keyed by the "overall process ID", which
105 GNU/Linux calls tgid, "thread group ID". */
107 struct inferior_list all_lwps
;
109 /* A list of all unknown processes which receive stop signals. Some other
110 process will presumably claim each of these as forked children
113 struct inferior_list stopped_pids
;
115 /* FIXME this is a bit of a hack, and could be removed. */
116 int stopping_threads
;
118 /* FIXME make into a target method? */
119 int using_threads
= 1;
121 /* This flag is true iff we've just created or attached to our first
122 inferior but it has not stopped yet. As soon as it does, we need
123 to call the low target's arch_setup callback. Doing this only on
124 the first inferior avoids reinializing the architecture on every
125 inferior, and avoids messing with the register caches of the
126 already running inferiors. NOTE: this assumes all inferiors under
127 control of gdbserver have the same architecture. */
128 static int new_inferior
;
130 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
131 int step
, int signal
, siginfo_t
*info
);
132 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
133 static void stop_all_lwps (void);
134 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
135 static int check_removed_breakpoint (struct lwp_info
*event_child
);
136 static void *add_lwp (ptid_t ptid
);
137 static int my_waitpid (int pid
, int *status
, int flags
);
138 static int linux_stopped_by_watchpoint (void);
139 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
141 struct pending_signals
145 struct pending_signals
*prev
;
148 #define PTRACE_ARG3_TYPE long
149 #define PTRACE_XFER_TYPE long
151 #ifdef HAVE_LINUX_REGSETS
152 static char *disabled_regsets
;
153 static int num_regsets
;
156 /* The read/write ends of the pipe registered as waitable file in the
158 static int linux_event_pipe
[2] = { -1, -1 };
160 /* True if we're currently in async mode. */
161 #define target_is_async_p() (linux_event_pipe[0] != -1)
163 static void send_sigstop (struct inferior_list_entry
*entry
);
164 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
166 /* Accepts an integer PID; Returns a string representing a file that
167 can be opened to get info for the child process.
168 Space for the result is malloc'd, caller must free. */
171 linux_child_pid_to_exec_file (int pid
)
175 name1
= xmalloc (MAXPATHLEN
);
176 name2
= xmalloc (MAXPATHLEN
);
177 memset (name2
, 0, MAXPATHLEN
);
179 sprintf (name1
, "/proc/%d/exe", pid
);
180 if (readlink (name1
, name2
, MAXPATHLEN
) > 0)
192 /* Return non-zero if HEADER is a 64-bit ELF file. */
195 elf_64_header_p (const Elf64_External_Ehdr
*header
)
197 return (header
->e_ident
[EI_MAG0
] == ELFMAG0
198 && header
->e_ident
[EI_MAG1
] == ELFMAG1
199 && header
->e_ident
[EI_MAG2
] == ELFMAG2
200 && header
->e_ident
[EI_MAG3
] == ELFMAG3
201 && header
->e_ident
[EI_CLASS
] == ELFCLASS64
);
204 /* Return non-zero if FILE is a 64-bit ELF file,
205 zero if the file is not a 64-bit ELF file,
206 and -1 if the file is not accessible or doesn't exist. */
209 elf_64_file_p (const char *file
)
211 Elf64_External_Ehdr header
;
214 fd
= open (file
, O_RDONLY
);
218 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
225 return elf_64_header_p (&header
);
229 delete_lwp (struct lwp_info
*lwp
)
231 remove_thread (get_lwp_thread (lwp
));
232 remove_inferior (&all_lwps
, &lwp
->head
);
233 free (lwp
->arch_private
);
237 /* Add a process to the common process list, and set its private
240 static struct process_info
*
241 linux_add_process (int pid
, int attached
)
243 struct process_info
*proc
;
245 /* Is this the first process? If so, then set the arch. */
246 if (all_processes
.head
== NULL
)
249 proc
= add_process (pid
, attached
);
250 proc
->private = xcalloc (1, sizeof (*proc
->private));
252 if (the_low_target
.new_process
!= NULL
)
253 proc
->private->arch_private
= the_low_target
.new_process ();
258 /* Remove a process from the common process list,
259 also freeing all private data. */
262 linux_remove_process (struct process_info
*process
)
264 free (process
->private->arch_private
);
265 free (process
->private);
266 remove_process (process
);
269 /* Handle a GNU/Linux extended wait response. If we see a clone
270 event, we need to add the new LWP to our list (and not report the
271 trap to higher layers). */
274 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
276 int event
= wstat
>> 16;
277 struct lwp_info
*new_lwp
;
279 if (event
== PTRACE_EVENT_CLONE
)
282 unsigned long new_pid
;
283 int ret
, status
= W_STOPCODE (SIGSTOP
);
285 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), 0, &new_pid
);
287 /* If we haven't already seen the new PID stop, wait for it now. */
288 if (! pull_pid_from_list (&stopped_pids
, new_pid
))
290 /* The new child has a pending SIGSTOP. We can't affect it until it
291 hits the SIGSTOP, but we're already attached. */
293 ret
= my_waitpid (new_pid
, &status
, __WALL
);
296 perror_with_name ("waiting for new child");
297 else if (ret
!= new_pid
)
298 warning ("wait returned unexpected PID %d", ret
);
299 else if (!WIFSTOPPED (status
))
300 warning ("wait returned unexpected status 0x%x", status
);
303 ptrace (PTRACE_SETOPTIONS
, new_pid
, 0, PTRACE_O_TRACECLONE
);
305 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
306 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
307 add_thread (ptid
, new_lwp
);
309 /* Either we're going to immediately resume the new thread
310 or leave it stopped. linux_resume_one_lwp is a nop if it
311 thinks the thread is currently running, so set this first
312 before calling linux_resume_one_lwp. */
313 new_lwp
->stopped
= 1;
315 /* Normally we will get the pending SIGSTOP. But in some cases
316 we might get another signal delivered to the group first.
317 If we do get another signal, be sure not to lose it. */
318 if (WSTOPSIG (status
) == SIGSTOP
)
320 if (! stopping_threads
)
321 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
325 new_lwp
->stop_expected
= 1;
326 if (stopping_threads
)
328 new_lwp
->status_pending_p
= 1;
329 new_lwp
->status_pending
= status
;
332 /* Pass the signal on. This is what GDB does - except
333 shouldn't we really report it instead? */
334 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
337 /* Always resume the current thread. If we are stopping
338 threads, it will have a pending SIGSTOP; we may as well
340 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
344 /* This function should only be called if the process got a SIGTRAP.
345 The SIGTRAP could mean several things.
347 On i386, where decr_pc_after_break is non-zero:
348 If we were single-stepping this process using PTRACE_SINGLESTEP,
349 we will get only the one SIGTRAP (even if the instruction we
350 stepped over was a breakpoint). The value of $eip will be the
352 If we continue the process using PTRACE_CONT, we will get a
353 SIGTRAP when we hit a breakpoint. The value of $eip will be
354 the instruction after the breakpoint (i.e. needs to be
355 decremented). If we report the SIGTRAP to GDB, we must also
356 report the undecremented PC. If we cancel the SIGTRAP, we
357 must resume at the decremented PC.
359 (Presumably, not yet tested) On a non-decr_pc_after_break machine
360 with hardware or kernel single-step:
361 If we single-step over a breakpoint instruction, our PC will
362 point at the following instruction. If we continue and hit a
363 breakpoint instruction, our PC will point at the breakpoint
369 CORE_ADDR stop_pc
= (*the_low_target
.get_pc
) ();
371 if (! get_thread_lwp (current_inferior
)->stepping
)
372 stop_pc
-= the_low_target
.decr_pc_after_break
;
375 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
381 add_lwp (ptid_t ptid
)
383 struct lwp_info
*lwp
;
385 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
386 memset (lwp
, 0, sizeof (*lwp
));
390 if (the_low_target
.new_thread
!= NULL
)
391 lwp
->arch_private
= the_low_target
.new_thread ();
393 add_inferior_to_list (&all_lwps
, &lwp
->head
);
398 /* Start an inferior process and returns its pid.
399 ALLARGS is a vector of program-name and args. */
402 linux_create_inferior (char *program
, char **allargs
)
404 struct lwp_info
*new_lwp
;
408 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
414 perror_with_name ("fork");
418 ptrace (PTRACE_TRACEME
, 0, 0, 0);
420 signal (__SIGRTMIN
+ 1, SIG_DFL
);
424 execv (program
, allargs
);
426 execvp (program
, allargs
);
428 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
434 linux_add_process (pid
, 0);
436 ptid
= ptid_build (pid
, pid
, 0);
437 new_lwp
= add_lwp (ptid
);
438 add_thread (ptid
, new_lwp
);
439 new_lwp
->must_set_ptrace_flags
= 1;
444 /* Attach to an inferior process. */
447 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
450 struct lwp_info
*new_lwp
;
452 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) != 0)
456 /* If we fail to attach to an LWP, just warn. */
457 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
458 strerror (errno
), errno
);
463 /* If we fail to attach to a process, report an error. */
464 error ("Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
465 strerror (errno
), errno
);
469 /* NOTE/FIXME: This lwp might have not been the tgid. */
470 ptid
= ptid_build (lwpid
, lwpid
, 0);
473 /* Note that extracting the pid from the current inferior is
474 safe, since we're always called in the context of the same
475 process as this new thread. */
476 int pid
= pid_of (get_thread_lwp (current_inferior
));
477 ptid
= ptid_build (pid
, lwpid
, 0);
480 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
481 add_thread (ptid
, new_lwp
);
483 /* We need to wait for SIGSTOP before being able to make the next
484 ptrace call on this LWP. */
485 new_lwp
->must_set_ptrace_flags
= 1;
487 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
490 There are several cases to consider here:
492 1) gdbserver has already attached to the process and is being notified
493 of a new thread that is being created.
494 In this case we should ignore that SIGSTOP and resume the process.
495 This is handled below by setting stop_expected = 1.
497 2) This is the first thread (the process thread), and we're attaching
498 to it via attach_inferior.
499 In this case we want the process thread to stop.
500 This is handled by having linux_attach clear stop_expected after
502 ??? If the process already has several threads we leave the other
505 3) GDB is connecting to gdbserver and is requesting an enumeration of all
507 In this case we want the thread to stop.
508 FIXME: This case is currently not properly handled.
509 We should wait for the SIGSTOP but don't. Things work apparently
510 because enough time passes between when we ptrace (ATTACH) and when
511 gdb makes the next ptrace call on the thread.
513 On the other hand, if we are currently trying to stop all threads, we
514 should treat the new thread as if we had sent it a SIGSTOP. This works
515 because we are guaranteed that the add_lwp call above added us to the
516 end of the list, and so the new thread has not yet reached
517 wait_for_sigstop (but will). */
518 if (! stopping_threads
)
519 new_lwp
->stop_expected
= 1;
523 linux_attach_lwp (unsigned long lwpid
)
525 linux_attach_lwp_1 (lwpid
, 0);
529 linux_attach (unsigned long pid
)
531 struct lwp_info
*lwp
;
533 linux_attach_lwp_1 (pid
, 1);
535 linux_add_process (pid
, 1);
539 /* Don't ignore the initial SIGSTOP if we just attached to this
540 process. It will be collected by wait shortly. */
541 lwp
= (struct lwp_info
*) find_inferior_id (&all_lwps
,
542 ptid_build (pid
, pid
, 0));
543 lwp
->stop_expected
= 0;
556 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
558 struct counter
*counter
= args
;
560 if (ptid_get_pid (entry
->id
) == counter
->pid
)
562 if (++counter
->count
> 1)
570 last_thread_of_process_p (struct thread_info
*thread
)
572 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
573 int pid
= ptid_get_pid (ptid
);
574 struct counter counter
= { pid
, 0 };
576 return (find_inferior (&all_threads
,
577 second_thread_of_pid_p
, &counter
) == NULL
);
580 /* Kill the inferior lwp. */
583 linux_kill_one_lwp (struct inferior_list_entry
*entry
, void *args
)
585 struct thread_info
*thread
= (struct thread_info
*) entry
;
586 struct lwp_info
*lwp
= get_thread_lwp (thread
);
588 int pid
= * (int *) args
;
590 if (ptid_get_pid (entry
->id
) != pid
)
593 /* We avoid killing the first thread here, because of a Linux kernel (at
594 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
595 the children get a chance to be reaped, it will remain a zombie
598 if (lwpid_of (lwp
) == pid
)
601 fprintf (stderr
, "lkop: is last of process %s\n",
602 target_pid_to_str (entry
->id
));
606 /* If we're killing a running inferior, make sure it is stopped
607 first, as PTRACE_KILL will not work otherwise. */
609 send_sigstop (&lwp
->head
);
613 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
615 /* Make sure it died. The loop is most likely unnecessary. */
616 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
617 } while (pid
> 0 && WIFSTOPPED (wstat
));
625 struct process_info
*process
;
626 struct lwp_info
*lwp
;
627 struct thread_info
*thread
;
631 process
= find_process_pid (pid
);
635 find_inferior (&all_threads
, linux_kill_one_lwp
, &pid
);
637 /* See the comment in linux_kill_one_lwp. We did not kill the first
638 thread in the list, so do so now. */
639 lwp
= find_lwp_pid (pid_to_ptid (pid
));
640 thread
= get_lwp_thread (lwp
);
643 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
644 lwpid_of (lwp
), pid
);
646 /* If we're killing a running inferior, make sure it is stopped
647 first, as PTRACE_KILL will not work otherwise. */
649 send_sigstop (&lwp
->head
);
653 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
655 /* Make sure it died. The loop is most likely unnecessary. */
656 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
657 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
660 linux_remove_process (process
);
665 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
667 struct thread_info
*thread
= (struct thread_info
*) entry
;
668 struct lwp_info
*lwp
= get_thread_lwp (thread
);
669 int pid
= * (int *) args
;
671 if (ptid_get_pid (entry
->id
) != pid
)
674 /* If we're detaching from a running inferior, make sure it is
675 stopped first, as PTRACE_DETACH will not work otherwise. */
678 int lwpid
= lwpid_of (lwp
);
680 stopping_threads
= 1;
681 send_sigstop (&lwp
->head
);
683 /* If this detects a new thread through a clone event, the new
684 thread is appended to the end of the lwp list, so we'll
685 eventually detach from it. */
686 wait_for_sigstop (&lwp
->head
);
687 stopping_threads
= 0;
689 /* If LWP exits while we're trying to stop it, there's nothing
691 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
696 /* Make sure the process isn't stopped at a breakpoint that's
698 check_removed_breakpoint (lwp
);
700 /* If this process is stopped but is expecting a SIGSTOP, then make
701 sure we take care of that now. This isn't absolutely guaranteed
702 to collect the SIGSTOP, but is fairly likely to. */
703 if (lwp
->stop_expected
)
706 /* Clear stop_expected, so that the SIGSTOP will be reported. */
707 lwp
->stop_expected
= 0;
709 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
710 linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
713 /* Flush any pending changes to the process's registers. */
714 regcache_invalidate_one ((struct inferior_list_entry
*)
715 get_lwp_thread (lwp
));
717 /* Finally, let it resume. */
718 ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0, 0);
725 any_thread_of (struct inferior_list_entry
*entry
, void *args
)
729 if (ptid_get_pid (entry
->id
) == *pid_p
)
736 linux_detach (int pid
)
738 struct process_info
*process
;
740 process
= find_process_pid (pid
);
745 (struct thread_info
*) find_inferior (&all_threads
, any_thread_of
, &pid
);
747 delete_all_breakpoints ();
748 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
749 linux_remove_process (process
);
757 struct process_info
*process
;
759 process
= find_process_pid (pid
);
764 ret
= my_waitpid (pid
, &status
, 0);
765 if (WIFEXITED (status
) || WIFSIGNALED (status
))
767 } while (ret
!= -1 || errno
!= ECHILD
);
770 /* Return nonzero if the given thread is still alive. */
772 linux_thread_alive (ptid_t ptid
)
774 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
776 /* We assume we always know if a thread exits. If a whole process
777 exited but we still haven't been able to report it to GDB, we'll
778 hold on to the last lwp of the dead process. */
785 /* Return nonzero if this process stopped at a breakpoint which
786 no longer appears to be inserted. Also adjust the PC
787 appropriately to resume where the breakpoint used to be. */
789 check_removed_breakpoint (struct lwp_info
*event_child
)
792 struct thread_info
*saved_inferior
;
794 if (event_child
->pending_is_breakpoint
== 0)
798 fprintf (stderr
, "Checking for breakpoint in lwp %ld.\n",
799 lwpid_of (event_child
));
801 saved_inferior
= current_inferior
;
802 current_inferior
= get_lwp_thread (event_child
);
804 stop_pc
= get_stop_pc ();
806 /* If the PC has changed since we stopped, then we shouldn't do
807 anything. This happens if, for instance, GDB handled the
808 decr_pc_after_break subtraction itself. */
809 if (stop_pc
!= event_child
->pending_stop_pc
)
812 fprintf (stderr
, "Ignoring, PC was changed. Old PC was 0x%08llx\n",
813 event_child
->pending_stop_pc
);
815 event_child
->pending_is_breakpoint
= 0;
816 current_inferior
= saved_inferior
;
820 /* If the breakpoint is still there, we will report hitting it. */
821 if ((*the_low_target
.breakpoint_at
) (stop_pc
))
824 fprintf (stderr
, "Ignoring, breakpoint is still present.\n");
825 current_inferior
= saved_inferior
;
830 fprintf (stderr
, "Removed breakpoint.\n");
832 /* For decr_pc_after_break targets, here is where we perform the
833 decrement. We go immediately from this function to resuming,
834 and can not safely call get_stop_pc () again. */
835 if (the_low_target
.set_pc
!= NULL
)
838 fprintf (stderr
, "Set pc to 0x%lx\n", (long) stop_pc
);
839 (*the_low_target
.set_pc
) (stop_pc
);
842 /* We consumed the pending SIGTRAP. */
843 event_child
->pending_is_breakpoint
= 0;
844 event_child
->status_pending_p
= 0;
845 event_child
->status_pending
= 0;
847 current_inferior
= saved_inferior
;
851 /* Return 1 if this lwp has an interesting status pending. This
852 function may silently resume an inferior lwp. */
854 status_pending_p (struct inferior_list_entry
*entry
, void *arg
)
856 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
857 ptid_t ptid
= * (ptid_t
*) arg
;
859 /* Check if we're only interested in events from a specific process
861 if (!ptid_equal (minus_one_ptid
, ptid
)
862 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
865 if (lwp
->status_pending_p
&& !lwp
->suspended
)
866 if (check_removed_breakpoint (lwp
))
868 /* This thread was stopped at a breakpoint, and the breakpoint
869 is now gone. We were told to continue (or step...) all threads,
870 so GDB isn't trying to single-step past this breakpoint.
871 So instead of reporting the old SIGTRAP, pretend we got to
872 the breakpoint just after it was removed instead of just
873 before; resume the process. */
874 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
878 return (lwp
->status_pending_p
&& !lwp
->suspended
);
882 same_lwp (struct inferior_list_entry
*entry
, void *data
)
884 ptid_t ptid
= *(ptid_t
*) data
;
887 if (ptid_get_lwp (ptid
) != 0)
888 lwp
= ptid_get_lwp (ptid
);
890 lwp
= ptid_get_pid (ptid
);
892 if (ptid_get_lwp (entry
->id
) == lwp
)
899 find_lwp_pid (ptid_t ptid
)
901 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
904 static struct lwp_info
*
905 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
908 int to_wait_for
= -1;
909 struct lwp_info
*child
= NULL
;
912 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
914 if (ptid_equal (ptid
, minus_one_ptid
))
915 to_wait_for
= -1; /* any child */
917 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
923 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
924 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
927 perror_with_name ("waitpid");
930 && (!WIFSTOPPED (*wstatp
)
931 || (WSTOPSIG (*wstatp
) != 32
932 && WSTOPSIG (*wstatp
) != 33)))
933 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
935 child
= find_lwp_pid (pid_to_ptid (ret
));
937 /* If we didn't find a process, one of two things presumably happened:
938 - A process we started and then detached from has exited. Ignore it.
939 - A process we are controlling has forked and the new child's stop
940 was reported to us by the kernel. Save its PID. */
941 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
943 add_pid_to_list (&stopped_pids
, ret
);
946 else if (child
== NULL
)
950 child
->pending_is_breakpoint
= 0;
952 child
->last_status
= *wstatp
;
954 /* Architecture-specific setup after inferior is running.
955 This needs to happen after we have attached to the inferior
956 and it is stopped for the first time, but before we access
957 any inferior registers. */
960 the_low_target
.arch_setup ();
961 #ifdef HAVE_LINUX_REGSETS
962 memset (disabled_regsets
, 0, num_regsets
);
968 && WIFSTOPPED (*wstatp
)
969 && the_low_target
.get_pc
!= NULL
)
971 struct thread_info
*saved_inferior
= current_inferior
;
974 current_inferior
= (struct thread_info
*)
975 find_inferior_id (&all_threads
, child
->head
.id
);
976 pc
= (*the_low_target
.get_pc
) ();
977 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
978 current_inferior
= saved_inferior
;
984 /* Wait for an event from child PID. If PID is -1, wait for any
985 child. Store the stop status through the status pointer WSTAT.
986 OPTIONS is passed to the waitpid call. Return 0 if no child stop
987 event was found and OPTIONS contains WNOHANG. Return the PID of
988 the stopped child otherwise. */
991 linux_wait_for_event_1 (ptid_t ptid
, int *wstat
, int options
)
994 struct lwp_info
*event_child
= NULL
;
996 struct lwp_info
*requested_child
= NULL
;
998 /* Check for a lwp with a pending status. */
999 /* It is possible that the user changed the pending task's registers since
1000 it stopped. We correctly handle the change of PC if we hit a breakpoint
1001 (in check_removed_breakpoint); signals should be reported anyway. */
1003 if (ptid_equal (ptid
, minus_one_ptid
)
1004 || ptid_equal (pid_to_ptid (ptid_get_pid (ptid
)), ptid
))
1006 event_child
= (struct lwp_info
*)
1007 find_inferior (&all_lwps
, status_pending_p
, &ptid
);
1008 if (debug_threads
&& event_child
)
1009 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1013 requested_child
= find_lwp_pid (ptid
);
1014 if (requested_child
->status_pending_p
1015 && !check_removed_breakpoint (requested_child
))
1016 event_child
= requested_child
;
1019 if (event_child
!= NULL
)
1022 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1023 lwpid_of (event_child
), event_child
->status_pending
);
1024 *wstat
= event_child
->status_pending
;
1025 event_child
->status_pending_p
= 0;
1026 event_child
->status_pending
= 0;
1027 current_inferior
= get_lwp_thread (event_child
);
1028 return lwpid_of (event_child
);
1031 /* We only enter this loop if no process has a pending wait status. Thus
1032 any action taken in response to a wait status inside this loop is
1033 responding as soon as we detect the status, not after any pending
1037 event_child
= linux_wait_for_lwp (ptid
, wstat
, options
);
1039 if ((options
& WNOHANG
) && event_child
== NULL
)
1042 if (event_child
== NULL
)
1043 error ("event from unknown child");
1045 current_inferior
= get_lwp_thread (event_child
);
1047 /* Check for thread exit. */
1048 if (! WIFSTOPPED (*wstat
))
1051 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1053 /* If the last thread is exiting, just return. */
1054 if (last_thread_of_process_p (current_inferior
))
1057 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1058 lwpid_of (event_child
));
1059 return lwpid_of (event_child
);
1062 delete_lwp (event_child
);
1066 current_inferior
= (struct thread_info
*) all_threads
.head
;
1068 fprintf (stderr
, "Current inferior is now %ld\n",
1069 lwpid_of (get_thread_lwp (current_inferior
)));
1073 current_inferior
= NULL
;
1075 fprintf (stderr
, "Current inferior is now <NULL>\n");
1078 /* If we were waiting for this particular child to do something...
1079 well, it did something. */
1080 if (requested_child
!= NULL
)
1081 return lwpid_of (event_child
);
1083 /* Wait for a more interesting event. */
1087 if (event_child
->must_set_ptrace_flags
)
1089 ptrace (PTRACE_SETOPTIONS
, lwpid_of (event_child
),
1090 0, PTRACE_O_TRACECLONE
);
1091 event_child
->must_set_ptrace_flags
= 0;
1094 if (WIFSTOPPED (*wstat
)
1095 && WSTOPSIG (*wstat
) == SIGSTOP
1096 && event_child
->stop_expected
)
1099 fprintf (stderr
, "Expected stop.\n");
1100 event_child
->stop_expected
= 0;
1101 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
1105 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1106 && *wstat
>> 16 != 0)
1108 handle_extended_wait (event_child
, *wstat
);
1112 /* If GDB is not interested in this signal, don't stop other
1113 threads, and don't report it to GDB. Just resume the
1114 inferior right away. We do this for threading-related
1115 signals as well as any that GDB specifically requested we
1116 ignore. But never ignore SIGSTOP if we sent it ourselves,
1117 and do not ignore signals when stepping - they may require
1118 special handling to skip the signal handler. */
1119 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
1121 if (WIFSTOPPED (*wstat
)
1122 && !event_child
->stepping
1124 #ifdef USE_THREAD_DB
1125 (current_process ()->private->thread_db_active
1126 && (WSTOPSIG (*wstat
) == __SIGRTMIN
1127 || WSTOPSIG (*wstat
) == __SIGRTMIN
+ 1))
1130 (pass_signals
[target_signal_from_host (WSTOPSIG (*wstat
))]
1131 && (WSTOPSIG (*wstat
) != SIGSTOP
|| !stopping_threads
))))
1133 siginfo_t info
, *info_p
;
1136 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
1137 WSTOPSIG (*wstat
), lwpid_of (event_child
));
1139 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
1143 linux_resume_one_lwp (event_child
,
1144 event_child
->stepping
,
1145 WSTOPSIG (*wstat
), info_p
);
1149 /* If this event was not handled above, and is not a SIGTRAP, report
1151 if (!WIFSTOPPED (*wstat
) || WSTOPSIG (*wstat
) != SIGTRAP
)
1152 return lwpid_of (event_child
);
1154 /* If this target does not support breakpoints, we simply report the
1155 SIGTRAP; it's of no concern to us. */
1156 if (the_low_target
.get_pc
== NULL
)
1157 return lwpid_of (event_child
);
1159 stop_pc
= get_stop_pc ();
1161 /* bp_reinsert will only be set if we were single-stepping.
1162 Notice that we will resume the process after hitting
1163 a gdbserver breakpoint; single-stepping to/over one
1164 is not supported (yet). */
1165 if (event_child
->bp_reinsert
!= 0)
1168 fprintf (stderr
, "Reinserted breakpoint.\n");
1169 reinsert_breakpoint (event_child
->bp_reinsert
);
1170 event_child
->bp_reinsert
= 0;
1172 /* Clear the single-stepping flag and SIGTRAP as we resume. */
1173 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1177 bp_status
= check_breakpoints (stop_pc
);
1182 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
1184 /* We hit one of our own breakpoints. We mark it as a pending
1185 breakpoint, so that check_removed_breakpoint () will do the PC
1186 adjustment for us at the appropriate time. */
1187 event_child
->pending_is_breakpoint
= 1;
1188 event_child
->pending_stop_pc
= stop_pc
;
1190 /* We may need to put the breakpoint back. We continue in the event
1191 loop instead of simply replacing the breakpoint right away,
1192 in order to not lose signals sent to the thread that hit the
1193 breakpoint. Unfortunately this increases the window where another
1194 thread could sneak past the removed breakpoint. For the current
1195 use of server-side breakpoints (thread creation) this is
1196 acceptable; but it needs to be considered before this breakpoint
1197 mechanism can be used in more general ways. For some breakpoints
1198 it may be necessary to stop all other threads, but that should
1199 be avoided where possible.
1201 If breakpoint_reinsert_addr is NULL, that means that we can
1202 use PTRACE_SINGLESTEP on this platform. Uninsert the breakpoint,
1203 mark it for reinsertion, and single-step.
1205 Otherwise, call the target function to figure out where we need
1206 our temporary breakpoint, create it, and continue executing this
1209 /* NOTE: we're lifting breakpoints in non-stop mode. This
1210 is currently only used for thread event breakpoints, so
1211 it isn't that bad as long as we have PTRACE_EVENT_CLONE
1214 /* No need to reinsert. */
1215 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1216 else if (the_low_target
.breakpoint_reinsert_addr
== NULL
)
1218 event_child
->bp_reinsert
= stop_pc
;
1219 uninsert_breakpoint (stop_pc
);
1220 linux_resume_one_lwp (event_child
, 1, 0, NULL
);
1224 reinsert_breakpoint_by_bp
1225 (stop_pc
, (*the_low_target
.breakpoint_reinsert_addr
) ());
1226 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
1233 fprintf (stderr
, "Hit a non-gdbserver breakpoint.\n");
1235 /* If we were single-stepping, we definitely want to report the
1236 SIGTRAP. Although the single-step operation has completed,
1237 do not clear clear the stepping flag yet; we need to check it
1238 in wait_for_sigstop. */
1239 if (event_child
->stepping
)
1240 return lwpid_of (event_child
);
1242 /* A SIGTRAP that we can't explain. It may have been a breakpoint.
1243 Check if it is a breakpoint, and if so mark the process information
1244 accordingly. This will handle both the necessary fiddling with the
1245 PC on decr_pc_after_break targets and suppressing extra threads
1246 hitting a breakpoint if two hit it at once and then GDB removes it
1247 after the first is reported. Arguably it would be better to report
1248 multiple threads hitting breakpoints simultaneously, but the current
1249 remote protocol does not allow this. */
1250 if ((*the_low_target
.breakpoint_at
) (stop_pc
))
1252 event_child
->pending_is_breakpoint
= 1;
1253 event_child
->pending_stop_pc
= stop_pc
;
1256 return lwpid_of (event_child
);
1264 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1268 if (ptid_is_pid (ptid
))
1270 /* A request to wait for a specific tgid. This is not possible
1271 with waitpid, so instead, we wait for any child, and leave
1272 children we're not interested in right now with a pending
1273 status to report later. */
1274 wait_ptid
= minus_one_ptid
;
1283 event_pid
= linux_wait_for_event_1 (wait_ptid
, wstat
, options
);
1286 && ptid_is_pid (ptid
) && ptid_get_pid (ptid
) != event_pid
)
1288 struct lwp_info
*event_child
= find_lwp_pid (pid_to_ptid (event_pid
));
1290 if (! WIFSTOPPED (*wstat
))
1291 mark_lwp_dead (event_child
, *wstat
);
1294 event_child
->status_pending_p
= 1;
1295 event_child
->status_pending
= *wstat
;
1303 /* Wait for process, returns status. */
1306 linux_wait_1 (ptid_t ptid
,
1307 struct target_waitstatus
*ourstatus
, int target_options
)
1310 struct thread_info
*thread
= NULL
;
1311 struct lwp_info
*lwp
= NULL
;
1315 /* Translate generic target options into linux options. */
1317 if (target_options
& TARGET_WNOHANG
)
1321 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
1323 /* If we were only supposed to resume one thread, only wait for
1324 that thread - if it's still alive. If it died, however - which
1325 can happen if we're coming from the thread death case below -
1326 then we need to make sure we restart the other threads. We could
1327 pick a thread at random or restart all; restarting all is less
1330 && !ptid_equal (cont_thread
, null_ptid
)
1331 && !ptid_equal (cont_thread
, minus_one_ptid
))
1333 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
1336 /* No stepping, no signal - unless one is pending already, of course. */
1339 struct thread_resume resume_info
;
1340 resume_info
.thread
= minus_one_ptid
;
1341 resume_info
.kind
= resume_continue
;
1342 resume_info
.sig
= 0;
1343 linux_resume (&resume_info
, 1);
1349 pid
= linux_wait_for_event (ptid
, &w
, options
);
1350 if (pid
== 0) /* only if TARGET_WNOHANG */
1353 lwp
= get_thread_lwp (current_inferior
);
1355 /* If we are waiting for a particular child, and it exited,
1356 linux_wait_for_event will return its exit status. Similarly if
1357 the last child exited. If this is not the last child, however,
1358 do not report it as exited until there is a 'thread exited' response
1359 available in the remote protocol. Instead, just wait for another event.
1360 This should be safe, because if the thread crashed we will already
1361 have reported the termination signal to GDB; that should stop any
1362 in-progress stepping operations, etc.
1364 Report the exit status of the last thread to exit. This matches
1365 LinuxThreads' behavior. */
1367 if (last_thread_of_process_p (current_inferior
))
1369 if (WIFEXITED (w
) || WIFSIGNALED (w
))
1371 int pid
= pid_of (lwp
);
1372 struct process_info
*process
= find_process_pid (pid
);
1375 linux_remove_process (process
);
1377 current_inferior
= NULL
;
1381 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
1382 ourstatus
->value
.integer
= WEXITSTATUS (w
);
1385 fprintf (stderr
, "\nChild exited with retcode = %x \n", WEXITSTATUS (w
));
1389 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
1390 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
1393 fprintf (stderr
, "\nChild terminated with signal = %x \n", WTERMSIG (w
));
1397 return pid_to_ptid (pid
);
1402 if (!WIFSTOPPED (w
))
1406 /* In all-stop, stop all threads. Be careful to only do this if
1407 we're about to report an event to GDB. */
1411 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
1413 if (lwp
->suspended
&& WSTOPSIG (w
) == SIGSTOP
)
1415 /* A thread that has been requested to stop by GDB with vCont;t,
1416 and it stopped cleanly, so report as SIG0. The use of
1417 SIGSTOP is an implementation detail. */
1418 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
1420 else if (lwp
->suspended
&& WSTOPSIG (w
) != SIGSTOP
)
1422 /* A thread that has been requested to stop by GDB with vCont;t,
1423 but, it stopped for other reasons. Set stop_expected so the
1424 pending SIGSTOP is ignored and the LWP is resumed. */
1425 lwp
->stop_expected
= 1;
1426 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
1430 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
1434 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
1435 target_pid_to_str (lwp
->head
.id
),
1437 ourstatus
->value
.sig
);
1439 return lwp
->head
.id
;
1442 /* Get rid of any pending event in the pipe. */
1444 async_file_flush (void)
1450 ret
= read (linux_event_pipe
[0], &buf
, 1);
1451 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
1454 /* Put something in the pipe, so the event loop wakes up. */
1456 async_file_mark (void)
1460 async_file_flush ();
1463 ret
= write (linux_event_pipe
[1], "+", 1);
1464 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
1466 /* Ignore EAGAIN. If the pipe is full, the event loop will already
1467 be awakened anyway. */
1471 linux_wait (ptid_t ptid
,
1472 struct target_waitstatus
*ourstatus
, int target_options
)
1477 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
1479 /* Flush the async file first. */
1480 if (target_is_async_p ())
1481 async_file_flush ();
1483 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
1485 /* If at least one stop was reported, there may be more. A single
1486 SIGCHLD can signal more than one child stop. */
1487 if (target_is_async_p ()
1488 && (target_options
& TARGET_WNOHANG
) != 0
1489 && !ptid_equal (event_ptid
, null_ptid
))
1495 /* Send a signal to an LWP. For LinuxThreads, kill is enough; however, if
1496 thread groups are in use, we need to use tkill. */
1499 kill_lwp (unsigned long lwpid
, int signo
)
1501 static int tkill_failed
;
1508 int ret
= syscall (SYS_tkill
, lwpid
, signo
);
1509 if (errno
!= ENOSYS
)
1516 return kill (lwpid
, signo
);
1520 send_sigstop (struct inferior_list_entry
*entry
)
1522 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1528 pid
= lwpid_of (lwp
);
1530 /* If we already have a pending stop signal for this process, don't
1532 if (lwp
->stop_expected
)
1535 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
1537 /* We clear the stop_expected flag so that wait_for_sigstop
1538 will receive the SIGSTOP event (instead of silently resuming and
1539 waiting again). It'll be reset below. */
1540 lwp
->stop_expected
= 0;
1545 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
1547 kill_lwp (pid
, SIGSTOP
);
1551 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
1553 /* It's dead, really. */
1556 /* Store the exit status for later. */
1557 lwp
->status_pending_p
= 1;
1558 lwp
->status_pending
= wstat
;
1560 /* So that check_removed_breakpoint doesn't try to figure out if
1561 this is stopped at a breakpoint. */
1562 lwp
->pending_is_breakpoint
= 0;
1564 /* Prevent trying to stop it. */
1567 /* No further stops are expected from a dead lwp. */
1568 lwp
->stop_expected
= 0;
1572 wait_for_sigstop (struct inferior_list_entry
*entry
)
1574 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1575 struct thread_info
*saved_inferior
;
1583 saved_inferior
= current_inferior
;
1584 if (saved_inferior
!= NULL
)
1585 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
1587 saved_tid
= null_ptid
; /* avoid bogus unused warning */
1589 ptid
= lwp
->head
.id
;
1591 linux_wait_for_event (ptid
, &wstat
, __WALL
);
1593 /* If we stopped with a non-SIGSTOP signal, save it for later
1594 and record the pending SIGSTOP. If the process exited, just
1596 if (WIFSTOPPED (wstat
)
1597 && WSTOPSIG (wstat
) != SIGSTOP
)
1600 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
1601 lwpid_of (lwp
), wstat
);
1603 /* Do not leave a pending single-step finish to be reported to
1604 the client. The client will give us a new action for this
1605 thread, possibly a continue request --- otherwise, the client
1606 would consider this pending SIGTRAP reported later a spurious
1608 if (WSTOPSIG (wstat
) == SIGTRAP
1610 && !linux_stopped_by_watchpoint ())
1613 fprintf (stderr
, " single-step SIGTRAP ignored\n");
1617 lwp
->status_pending_p
= 1;
1618 lwp
->status_pending
= wstat
;
1620 lwp
->stop_expected
= 1;
1622 else if (!WIFSTOPPED (wstat
))
1625 fprintf (stderr
, "Process %ld exited while stopping LWPs\n",
1628 /* Leave this status pending for the next time we're able to
1629 report it. In the mean time, we'll report this lwp as dead
1630 to GDB, so GDB doesn't try to read registers and memory from
1632 mark_lwp_dead (lwp
, wstat
);
1635 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
1636 current_inferior
= saved_inferior
;
1640 fprintf (stderr
, "Previously current thread died.\n");
1644 /* We can't change the current inferior behind GDB's back,
1645 otherwise, a subsequent command may apply to the wrong
1647 current_inferior
= NULL
;
1651 /* Set a valid thread as current. */
1652 set_desired_inferior (0);
1658 stop_all_lwps (void)
1660 stopping_threads
= 1;
1661 for_each_inferior (&all_lwps
, send_sigstop
);
1662 for_each_inferior (&all_lwps
, wait_for_sigstop
);
1663 stopping_threads
= 0;
1666 /* Resume execution of the inferior process.
1667 If STEP is nonzero, single-step it.
1668 If SIGNAL is nonzero, give it that signal. */
1671 linux_resume_one_lwp (struct lwp_info
*lwp
,
1672 int step
, int signal
, siginfo_t
*info
)
1674 struct thread_info
*saved_inferior
;
1676 if (lwp
->stopped
== 0)
1679 /* If we have pending signals or status, and a new signal, enqueue the
1680 signal. Also enqueue the signal if we are waiting to reinsert a
1681 breakpoint; it will be picked up again below. */
1683 && (lwp
->status_pending_p
|| lwp
->pending_signals
!= NULL
1684 || lwp
->bp_reinsert
!= 0))
1686 struct pending_signals
*p_sig
;
1687 p_sig
= xmalloc (sizeof (*p_sig
));
1688 p_sig
->prev
= lwp
->pending_signals
;
1689 p_sig
->signal
= signal
;
1691 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1693 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
1694 lwp
->pending_signals
= p_sig
;
1697 if (lwp
->status_pending_p
&& !check_removed_breakpoint (lwp
))
1700 saved_inferior
= current_inferior
;
1701 current_inferior
= get_lwp_thread (lwp
);
1704 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
1705 lwpid_of (lwp
), step
? "step" : "continue", signal
,
1706 lwp
->stop_expected
? "expected" : "not expected");
1708 /* This bit needs some thinking about. If we get a signal that
1709 we must report while a single-step reinsert is still pending,
1710 we often end up resuming the thread. It might be better to
1711 (ew) allow a stack of pending events; then we could be sure that
1712 the reinsert happened right away and not lose any signals.
1714 Making this stack would also shrink the window in which breakpoints are
1715 uninserted (see comment in linux_wait_for_lwp) but not enough for
1716 complete correctness, so it won't solve that problem. It may be
1717 worthwhile just to solve this one, however. */
1718 if (lwp
->bp_reinsert
!= 0)
1721 fprintf (stderr
, " pending reinsert at %08lx", (long)lwp
->bp_reinsert
);
1723 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
1726 /* Postpone any pending signal. It was enqueued above. */
1730 check_removed_breakpoint (lwp
);
1732 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
1734 CORE_ADDR pc
= (*the_low_target
.get_pc
) ();
1735 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
1738 /* If we have pending signals, consume one unless we are trying to reinsert
1740 if (lwp
->pending_signals
!= NULL
&& lwp
->bp_reinsert
== 0)
1742 struct pending_signals
**p_sig
;
1744 p_sig
= &lwp
->pending_signals
;
1745 while ((*p_sig
)->prev
!= NULL
)
1746 p_sig
= &(*p_sig
)->prev
;
1748 signal
= (*p_sig
)->signal
;
1749 if ((*p_sig
)->info
.si_signo
!= 0)
1750 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
1756 if (the_low_target
.prepare_to_resume
!= NULL
)
1757 the_low_target
.prepare_to_resume (lwp
);
1759 regcache_invalidate_one ((struct inferior_list_entry
*)
1760 get_lwp_thread (lwp
));
1763 lwp
->stepping
= step
;
1764 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0, signal
);
1766 current_inferior
= saved_inferior
;
1769 /* ESRCH from ptrace either means that the thread was already
1770 running (an error) or that it is gone (a race condition). If
1771 it's gone, we will get a notification the next time we wait,
1772 so we can ignore the error. We could differentiate these
1773 two, but it's tricky without waiting; the thread still exists
1774 as a zombie, so sending it signal 0 would succeed. So just
1779 perror_with_name ("ptrace");
1783 struct thread_resume_array
1785 struct thread_resume
*resume
;
1789 /* This function is called once per thread. We look up the thread
1790 in RESUME_PTR, and mark the thread with a pointer to the appropriate
1793 This algorithm is O(threads * resume elements), but resume elements
1794 is small (and will remain small at least until GDB supports thread
1797 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
1799 struct lwp_info
*lwp
;
1800 struct thread_info
*thread
;
1802 struct thread_resume_array
*r
;
1804 thread
= (struct thread_info
*) entry
;
1805 lwp
= get_thread_lwp (thread
);
1808 for (ndx
= 0; ndx
< r
->n
; ndx
++)
1810 ptid_t ptid
= r
->resume
[ndx
].thread
;
1811 if (ptid_equal (ptid
, minus_one_ptid
)
1812 || ptid_equal (ptid
, entry
->id
)
1813 || (ptid_is_pid (ptid
)
1814 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
1815 || (ptid_get_lwp (ptid
) == -1
1816 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
1818 lwp
->resume
= &r
->resume
[ndx
];
1823 /* No resume action for this thread. */
1830 /* Set *FLAG_P if this lwp has an interesting status pending. */
1832 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
1834 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1836 /* LWPs which will not be resumed are not interesting, because
1837 we might not wait for them next time through linux_wait. */
1838 if (lwp
->resume
== NULL
)
1841 /* If this thread has a removed breakpoint, we won't have any
1842 events to report later, so check now. check_removed_breakpoint
1843 may clear status_pending_p. We avoid calling check_removed_breakpoint
1844 for any thread that we are not otherwise going to resume - this
1845 lets us preserve stopped status when two threads hit a breakpoint.
1846 GDB removes the breakpoint to single-step a particular thread
1847 past it, then re-inserts it and resumes all threads. We want
1848 to report the second thread without resuming it in the interim. */
1849 if (lwp
->status_pending_p
)
1850 check_removed_breakpoint (lwp
);
1852 if (lwp
->status_pending_p
)
1853 * (int *) flag_p
= 1;
1858 /* This function is called once per thread. We check the thread's resume
1859 request, which will tell us whether to resume, step, or leave the thread
1860 stopped; and what signal, if any, it should be sent.
1862 For threads which we aren't explicitly told otherwise, we preserve
1863 the stepping flag; this is used for stepping over gdbserver-placed
1866 If pending_flags was set in any thread, we queue any needed
1867 signals, since we won't actually resume. We already have a pending
1868 event to report, so we don't need to preserve any step requests;
1869 they should be re-issued if necessary. */
1872 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
1874 struct lwp_info
*lwp
;
1875 struct thread_info
*thread
;
1877 int pending_flag
= * (int *) arg
;
1879 thread
= (struct thread_info
*) entry
;
1880 lwp
= get_thread_lwp (thread
);
1882 if (lwp
->resume
== NULL
)
1885 if (lwp
->resume
->kind
== resume_stop
)
1888 fprintf (stderr
, "suspending LWP %ld\n", lwpid_of (lwp
));
1893 fprintf (stderr
, "running -> suspending LWP %ld\n", lwpid_of (lwp
));
1896 send_sigstop (&lwp
->head
);
1903 fprintf (stderr
, "already stopped/suspended LWP %ld\n",
1906 fprintf (stderr
, "already stopped/not suspended LWP %ld\n",
1910 /* Make sure we leave the LWP suspended, so we don't try to
1911 resume it without GDB telling us to. FIXME: The LWP may
1912 have been stopped in an internal event that was not meant
1913 to be notified back to GDB (e.g., gdbserver breakpoint),
1914 so we should be reporting a stop event in that case
1919 /* For stop requests, we're done. */
1926 /* If this thread which is about to be resumed has a pending status,
1927 then don't resume any threads - we can just report the pending
1928 status. Make sure to queue any signals that would otherwise be
1929 sent. In all-stop mode, we do this decision based on if *any*
1930 thread has a pending status. */
1932 resume_status_pending_p (&lwp
->head
, &pending_flag
);
1937 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
1939 if (ptid_equal (lwp
->resume
->thread
, minus_one_ptid
)
1941 && lwp
->pending_is_breakpoint
)
1944 step
= (lwp
->resume
->kind
== resume_step
);
1946 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
1951 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
1953 /* If we have a new signal, enqueue the signal. */
1954 if (lwp
->resume
->sig
!= 0)
1956 struct pending_signals
*p_sig
;
1957 p_sig
= xmalloc (sizeof (*p_sig
));
1958 p_sig
->prev
= lwp
->pending_signals
;
1959 p_sig
->signal
= lwp
->resume
->sig
;
1960 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1962 /* If this is the same signal we were previously stopped by,
1963 make sure to queue its siginfo. We can ignore the return
1964 value of ptrace; if it fails, we'll skip
1965 PTRACE_SETSIGINFO. */
1966 if (WIFSTOPPED (lwp
->last_status
)
1967 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
1968 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
1970 lwp
->pending_signals
= p_sig
;
1979 linux_resume (struct thread_resume
*resume_info
, size_t n
)
1982 struct thread_resume_array array
= { resume_info
, n
};
1984 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
1986 /* If there is a thread which would otherwise be resumed, which
1987 has a pending status, then don't resume any threads - we can just
1988 report the pending status. Make sure to queue any signals
1989 that would otherwise be sent. In non-stop mode, we'll apply this
1990 logic to each thread individually. */
1993 find_inferior (&all_lwps
, resume_status_pending_p
, &pending_flag
);
1998 fprintf (stderr
, "Not resuming, pending status\n");
2000 fprintf (stderr
, "Resuming, no pending status\n");
2003 find_inferior (&all_threads
, linux_resume_one_thread
, &pending_flag
);
2006 #ifdef HAVE_LINUX_USRREGS
2009 register_addr (int regnum
)
2013 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
2014 error ("Invalid register number %d.", regnum
);
2016 addr
= the_low_target
.regmap
[regnum
];
2021 /* Fetch one register. */
2023 fetch_register (int regno
)
2030 if (regno
>= the_low_target
.num_regs
)
2032 if ((*the_low_target
.cannot_fetch_register
) (regno
))
2035 regaddr
= register_addr (regno
);
2039 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2040 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2041 & - sizeof (PTRACE_XFER_TYPE
));
2042 buf
= alloca (size
);
2043 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
2046 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
2047 ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_ARG3_TYPE
) regaddr
, 0);
2048 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
2051 /* Warning, not error, in case we are attached; sometimes the
2052 kernel doesn't let us at the registers. */
2053 char *err
= strerror (errno
);
2054 char *msg
= alloca (strlen (err
) + 128);
2055 sprintf (msg
, "reading register %d: %s", regno
, err
);
2061 if (the_low_target
.supply_ptrace_register
)
2062 the_low_target
.supply_ptrace_register (regno
, buf
);
2064 supply_register (regno
, buf
);
2069 /* Fetch all registers, or just one, from the child process. */
2071 usr_fetch_inferior_registers (int regno
)
2074 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
2075 fetch_register (regno
);
2077 fetch_register (regno
);
2080 /* Store our register values back into the inferior.
2081 If REGNO is -1, do this for all registers.
2082 Otherwise, REGNO specifies which register (so we can save time). */
2084 usr_store_inferior_registers (int regno
)
2093 if (regno
>= the_low_target
.num_regs
)
2096 if ((*the_low_target
.cannot_store_register
) (regno
) == 1)
2099 regaddr
= register_addr (regno
);
2103 size
= (register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2104 & - sizeof (PTRACE_XFER_TYPE
);
2105 buf
= alloca (size
);
2106 memset (buf
, 0, size
);
2108 if (the_low_target
.collect_ptrace_register
)
2109 the_low_target
.collect_ptrace_register (regno
, buf
);
2111 collect_register (regno
, buf
);
2113 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2114 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
2117 ptrace (PTRACE_POKEUSER
, pid
, (PTRACE_ARG3_TYPE
) regaddr
,
2118 *(PTRACE_XFER_TYPE
*) (buf
+ i
));
2121 /* At this point, ESRCH should mean the process is
2122 already gone, in which case we simply ignore attempts
2123 to change its registers. See also the related
2124 comment in linux_resume_one_lwp. */
2128 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
2130 char *err
= strerror (errno
);
2131 char *msg
= alloca (strlen (err
) + 128);
2132 sprintf (msg
, "writing register %d: %s",
2138 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
2142 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
2143 usr_store_inferior_registers (regno
);
2145 #endif /* HAVE_LINUX_USRREGS */
2149 #ifdef HAVE_LINUX_REGSETS
2152 regsets_fetch_inferior_registers ()
2154 struct regset_info
*regset
;
2155 int saw_general_regs
= 0;
2158 regset
= target_regsets
;
2160 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2161 while (regset
->size
>= 0)
2166 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
2172 buf
= xmalloc (regset
->size
);
2174 res
= ptrace (regset
->get_request
, pid
, 0, buf
);
2176 res
= ptrace (regset
->get_request
, pid
, buf
, 0);
2182 /* If we get EIO on a regset, do not try it again for
2184 disabled_regsets
[regset
- target_regsets
] = 1;
2191 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
2196 else if (regset
->type
== GENERAL_REGS
)
2197 saw_general_regs
= 1;
2198 regset
->store_function (buf
);
2202 if (saw_general_regs
)
2209 regsets_store_inferior_registers ()
2211 struct regset_info
*regset
;
2212 int saw_general_regs
= 0;
2215 regset
= target_regsets
;
2217 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2218 while (regset
->size
>= 0)
2223 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
2229 buf
= xmalloc (regset
->size
);
2231 /* First fill the buffer with the current register set contents,
2232 in case there are any items in the kernel's regset that are
2233 not in gdbserver's regcache. */
2235 res
= ptrace (regset
->get_request
, pid
, 0, buf
);
2237 res
= ptrace (regset
->get_request
, pid
, buf
, 0);
2242 /* Then overlay our cached registers on that. */
2243 regset
->fill_function (buf
);
2245 /* Only now do we write the register set. */
2247 res
= ptrace (regset
->set_request
, pid
, 0, buf
);
2249 res
= ptrace (regset
->set_request
, pid
, buf
, 0);
2257 /* If we get EIO on a regset, do not try it again for
2259 disabled_regsets
[regset
- target_regsets
] = 1;
2263 else if (errno
== ESRCH
)
2265 /* At this point, ESRCH should mean the process is
2266 already gone, in which case we simply ignore attempts
2267 to change its registers. See also the related
2268 comment in linux_resume_one_lwp. */
2274 perror ("Warning: ptrace(regsets_store_inferior_registers)");
2277 else if (regset
->type
== GENERAL_REGS
)
2278 saw_general_regs
= 1;
2282 if (saw_general_regs
)
2289 #endif /* HAVE_LINUX_REGSETS */
2293 linux_fetch_registers (int regno
)
2295 #ifdef HAVE_LINUX_REGSETS
2296 if (regsets_fetch_inferior_registers () == 0)
2299 #ifdef HAVE_LINUX_USRREGS
2300 usr_fetch_inferior_registers (regno
);
2305 linux_store_registers (int regno
)
2307 #ifdef HAVE_LINUX_REGSETS
2308 if (regsets_store_inferior_registers () == 0)
2311 #ifdef HAVE_LINUX_USRREGS
2312 usr_store_inferior_registers (regno
);
2317 /* Copy LEN bytes from inferior's memory starting at MEMADDR
2318 to debugger memory starting at MYADDR. */
2321 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
2324 /* Round starting address down to longword boundary. */
2325 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
2326 /* Round ending address up; get number of longwords that makes. */
2328 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
2329 / sizeof (PTRACE_XFER_TYPE
);
2330 /* Allocate buffer of that many longwords. */
2331 register PTRACE_XFER_TYPE
*buffer
2332 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
2335 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2337 /* Try using /proc. Don't bother for one word. */
2338 if (len
>= 3 * sizeof (long))
2340 /* We could keep this file open and cache it - possibly one per
2341 thread. That requires some juggling, but is even faster. */
2342 sprintf (filename
, "/proc/%d/mem", pid
);
2343 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
2347 /* If pread64 is available, use it. It's faster if the kernel
2348 supports it (only one syscall), and it's 64-bit safe even on
2349 32-bit platforms (for instance, SPARC debugging a SPARC64
2352 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
2354 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, memaddr
, len
) != len
)
2366 /* Read all the longwords */
2367 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
2370 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
, (PTRACE_ARG3_TYPE
) addr
, 0);
2375 /* Copy appropriate bytes out of the buffer. */
2377 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
2383 /* Copy LEN bytes of data from debugger memory at MYADDR
2384 to inferior's memory at MEMADDR.
2385 On failure (cannot write the inferior)
2386 returns the value of errno. */
2389 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
2392 /* Round starting address down to longword boundary. */
2393 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
2394 /* Round ending address up; get number of longwords that makes. */
2396 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1) / sizeof (PTRACE_XFER_TYPE
);
2397 /* Allocate buffer of that many longwords. */
2398 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
2399 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2403 /* Dump up to four bytes. */
2404 unsigned int val
= * (unsigned int *) myaddr
;
2410 val
= val
& 0xffffff;
2411 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
2412 val
, (long)memaddr
);
2415 /* Fill start and end extra bytes of buffer with existing memory data. */
2417 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
, (PTRACE_ARG3_TYPE
) addr
, 0);
2422 = ptrace (PTRACE_PEEKTEXT
, pid
,
2423 (PTRACE_ARG3_TYPE
) (addr
+ (count
- 1)
2424 * sizeof (PTRACE_XFER_TYPE
)),
2428 /* Copy data to be written over corresponding part of buffer */
2430 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)), myaddr
, len
);
2432 /* Write the entire buffer. */
2434 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
2437 ptrace (PTRACE_POKETEXT
, pid
, (PTRACE_ARG3_TYPE
) addr
, buffer
[i
]);
2445 static int linux_supports_tracefork_flag
;
2447 /* Helper functions for linux_test_for_tracefork, called via clone (). */
2450 linux_tracefork_grandchild (void *arg
)
2455 #define STACK_SIZE 4096
2458 linux_tracefork_child (void *arg
)
2460 ptrace (PTRACE_TRACEME
, 0, 0, 0);
2461 kill (getpid (), SIGSTOP
);
2463 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
2464 CLONE_VM
| SIGCHLD
, NULL
);
2466 clone (linux_tracefork_grandchild
, arg
+ STACK_SIZE
,
2467 CLONE_VM
| SIGCHLD
, NULL
);
2472 /* Wrapper function for waitpid which handles EINTR, and emulates
2473 __WALL for systems where that is not available. */
2476 my_waitpid (int pid
, int *status
, int flags
)
2481 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
2485 sigset_t block_mask
, org_mask
, wake_mask
;
2488 wnohang
= (flags
& WNOHANG
) != 0;
2489 flags
&= ~(__WALL
| __WCLONE
);
2492 /* Block all signals while here. This avoids knowing about
2493 LinuxThread's signals. */
2494 sigfillset (&block_mask
);
2495 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
2497 /* ... except during the sigsuspend below. */
2498 sigemptyset (&wake_mask
);
2502 /* Since all signals are blocked, there's no need to check
2504 ret
= waitpid (pid
, status
, flags
);
2507 if (ret
== -1 && out_errno
!= ECHILD
)
2512 if (flags
& __WCLONE
)
2514 /* We've tried both flavors now. If WNOHANG is set,
2515 there's nothing else to do, just bail out. */
2520 fprintf (stderr
, "blocking\n");
2522 /* Block waiting for signals. */
2523 sigsuspend (&wake_mask
);
2529 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
2534 ret
= waitpid (pid
, status
, flags
);
2535 while (ret
== -1 && errno
== EINTR
);
2540 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
2541 pid
, flags
, status
? *status
: -1, ret
);
2547 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
2548 sure that we can enable the option, and that it had the desired
2552 linux_test_for_tracefork (void)
2554 int child_pid
, ret
, status
;
2556 char *stack
= xmalloc (STACK_SIZE
* 4);
2558 linux_supports_tracefork_flag
= 0;
2560 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
2562 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
2563 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
2565 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
2566 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
2568 if (child_pid
== -1)
2569 perror_with_name ("clone");
2571 ret
= my_waitpid (child_pid
, &status
, 0);
2573 perror_with_name ("waitpid");
2574 else if (ret
!= child_pid
)
2575 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
2576 if (! WIFSTOPPED (status
))
2577 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
2579 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0, PTRACE_O_TRACEFORK
);
2582 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
2585 warning ("linux_test_for_tracefork: failed to kill child");
2589 ret
= my_waitpid (child_pid
, &status
, 0);
2590 if (ret
!= child_pid
)
2591 warning ("linux_test_for_tracefork: failed to wait for killed child");
2592 else if (!WIFSIGNALED (status
))
2593 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
2594 "killed child", status
);
2599 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
2601 warning ("linux_test_for_tracefork: failed to resume child");
2603 ret
= my_waitpid (child_pid
, &status
, 0);
2605 if (ret
== child_pid
&& WIFSTOPPED (status
)
2606 && status
>> 16 == PTRACE_EVENT_FORK
)
2609 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
2610 if (ret
== 0 && second_pid
!= 0)
2614 linux_supports_tracefork_flag
= 1;
2615 my_waitpid (second_pid
, &second_status
, 0);
2616 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
2618 warning ("linux_test_for_tracefork: failed to kill second child");
2619 my_waitpid (second_pid
, &status
, 0);
2623 warning ("linux_test_for_tracefork: unexpected result from waitpid "
2624 "(%d, status 0x%x)", ret
, status
);
2628 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
2630 warning ("linux_test_for_tracefork: failed to kill child");
2631 my_waitpid (child_pid
, &status
, 0);
2633 while (WIFSTOPPED (status
));
2640 linux_look_up_symbols (void)
2642 #ifdef USE_THREAD_DB
2643 struct process_info
*proc
= current_process ();
2645 if (proc
->private->thread_db_active
)
2648 proc
->private->thread_db_active
2649 = thread_db_init (!linux_supports_tracefork_flag
);
2654 linux_request_interrupt (void)
2656 extern unsigned long signal_pid
;
2658 if (!ptid_equal (cont_thread
, null_ptid
)
2659 && !ptid_equal (cont_thread
, minus_one_ptid
))
2661 struct lwp_info
*lwp
;
2664 lwp
= get_thread_lwp (current_inferior
);
2665 lwpid
= lwpid_of (lwp
);
2666 kill_lwp (lwpid
, SIGINT
);
2669 kill_lwp (signal_pid
, SIGINT
);
2672 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
2673 to debugger memory starting at MYADDR. */
2676 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
2678 char filename
[PATH_MAX
];
2680 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2682 snprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
2684 fd
= open (filename
, O_RDONLY
);
2688 if (offset
!= (CORE_ADDR
) 0
2689 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
2692 n
= read (fd
, myaddr
, len
);
2699 /* These breakpoint and watchpoint related wrapper functions simply
2700 pass on the function call if the target has registered a
2701 corresponding function. */
2704 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
2706 if (the_low_target
.insert_point
!= NULL
)
2707 return the_low_target
.insert_point (type
, addr
, len
);
2709 /* Unsupported (see target.h). */
2714 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
2716 if (the_low_target
.remove_point
!= NULL
)
2717 return the_low_target
.remove_point (type
, addr
, len
);
2719 /* Unsupported (see target.h). */
2724 linux_stopped_by_watchpoint (void)
2726 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2727 return the_low_target
.stopped_by_watchpoint ();
2733 linux_stopped_data_address (void)
2735 if (the_low_target
.stopped_data_address
!= NULL
)
2736 return the_low_target
.stopped_data_address ();
2741 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
2742 #if defined(__mcoldfire__)
2743 /* These should really be defined in the kernel's ptrace.h header. */
2744 #define PT_TEXT_ADDR 49*4
2745 #define PT_DATA_ADDR 50*4
2746 #define PT_TEXT_END_ADDR 51*4
2749 /* Under uClinux, programs are loaded at non-zero offsets, which we need
2750 to tell gdb about. */
2753 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
2755 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
2756 unsigned long text
, text_end
, data
;
2757 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
2761 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
2762 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
2763 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
2767 /* Both text and data offsets produced at compile-time (and so
2768 used by gdb) are relative to the beginning of the program,
2769 with the data segment immediately following the text segment.
2770 However, the actual runtime layout in memory may put the data
2771 somewhere else, so when we send gdb a data base-address, we
2772 use the real data base address and subtract the compile-time
2773 data base-address from it (which is just the length of the
2774 text segment). BSS immediately follows data in both
2777 *data_p
= data
- (text_end
- text
);
2787 linux_qxfer_osdata (const char *annex
,
2788 unsigned char *readbuf
, unsigned const char *writebuf
,
2789 CORE_ADDR offset
, int len
)
2791 /* We make the process list snapshot when the object starts to be
2793 static const char *buf
;
2794 static long len_avail
= -1;
2795 static struct buffer buffer
;
2799 if (strcmp (annex
, "processes") != 0)
2802 if (!readbuf
|| writebuf
)
2807 if (len_avail
!= -1 && len_avail
!= 0)
2808 buffer_free (&buffer
);
2811 buffer_init (&buffer
);
2812 buffer_grow_str (&buffer
, "<osdata type=\"processes\">");
2814 dirp
= opendir ("/proc");
2818 while ((dp
= readdir (dirp
)) != NULL
)
2820 struct stat statbuf
;
2821 char procentry
[sizeof ("/proc/4294967295")];
2823 if (!isdigit (dp
->d_name
[0])
2824 || strlen (dp
->d_name
) > sizeof ("4294967295") - 1)
2827 sprintf (procentry
, "/proc/%s", dp
->d_name
);
2828 if (stat (procentry
, &statbuf
) == 0
2829 && S_ISDIR (statbuf
.st_mode
))
2833 char cmd
[MAXPATHLEN
+ 1];
2834 struct passwd
*entry
;
2836 sprintf (pathname
, "/proc/%s/cmdline", dp
->d_name
);
2837 entry
= getpwuid (statbuf
.st_uid
);
2839 if ((f
= fopen (pathname
, "r")) != NULL
)
2841 size_t len
= fread (cmd
, 1, sizeof (cmd
) - 1, f
);
2845 for (i
= 0; i
< len
; i
++)
2853 "<column name=\"pid\">%s</column>"
2854 "<column name=\"user\">%s</column>"
2855 "<column name=\"command\">%s</column>"
2858 entry
? entry
->pw_name
: "?",
2868 buffer_grow_str0 (&buffer
, "</osdata>\n");
2869 buf
= buffer_finish (&buffer
);
2870 len_avail
= strlen (buf
);
2873 if (offset
>= len_avail
)
2875 /* Done. Get rid of the data. */
2876 buffer_free (&buffer
);
2882 if (len
> len_avail
- offset
)
2883 len
= len_avail
- offset
;
2884 memcpy (readbuf
, buf
+ offset
, len
);
2889 /* Convert a native/host siginfo object, into/from the siginfo in the
2890 layout of the inferiors' architecture. */
2893 siginfo_fixup (struct siginfo
*siginfo
, void *inf_siginfo
, int direction
)
2897 if (the_low_target
.siginfo_fixup
!= NULL
)
2898 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
2900 /* If there was no callback, or the callback didn't do anything,
2901 then just do a straight memcpy. */
2905 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
2907 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
2912 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
2913 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
2916 struct siginfo siginfo
;
2917 char inf_siginfo
[sizeof (struct siginfo
)];
2919 if (current_inferior
== NULL
)
2922 pid
= lwpid_of (get_thread_lwp (current_inferior
));
2925 fprintf (stderr
, "%s siginfo for lwp %d.\n",
2926 readbuf
!= NULL
? "Reading" : "Writing",
2929 if (offset
> sizeof (siginfo
))
2932 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
2935 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
2936 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
2937 inferior with a 64-bit GDBSERVER should look the same as debugging it
2938 with a 32-bit GDBSERVER, we need to convert it. */
2939 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
2941 if (offset
+ len
> sizeof (siginfo
))
2942 len
= sizeof (siginfo
) - offset
;
2944 if (readbuf
!= NULL
)
2945 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
2948 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
2950 /* Convert back to ptrace layout before flushing it out. */
2951 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
2953 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
2960 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
2961 so we notice when children change state; as the handler for the
2962 sigsuspend in my_waitpid. */
2965 sigchld_handler (int signo
)
2967 int old_errno
= errno
;
2970 /* fprintf is not async-signal-safe, so call write directly. */
2971 write (2, "sigchld_handler\n", sizeof ("sigchld_handler\n") - 1);
2973 if (target_is_async_p ())
2974 async_file_mark (); /* trigger a linux_wait */
2980 linux_supports_non_stop (void)
2986 linux_async (int enable
)
2988 int previous
= (linux_event_pipe
[0] != -1);
2990 if (previous
!= enable
)
2993 sigemptyset (&mask
);
2994 sigaddset (&mask
, SIGCHLD
);
2996 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
3000 if (pipe (linux_event_pipe
) == -1)
3001 fatal ("creating event pipe failed.");
3003 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
3004 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
3006 /* Register the event loop handler. */
3007 add_file_handler (linux_event_pipe
[0],
3008 handle_target_event
, NULL
);
3010 /* Always trigger a linux_wait. */
3015 delete_file_handler (linux_event_pipe
[0]);
3017 close (linux_event_pipe
[0]);
3018 close (linux_event_pipe
[1]);
3019 linux_event_pipe
[0] = -1;
3020 linux_event_pipe
[1] = -1;
3023 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
3030 linux_start_non_stop (int nonstop
)
3032 /* Register or unregister from event-loop accordingly. */
3033 linux_async (nonstop
);
3038 linux_supports_multi_process (void)
3044 /* Enumerate spufs IDs for process PID. */
3046 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
3052 struct dirent
*entry
;
3054 sprintf (path
, "/proc/%ld/fd", pid
);
3055 dir
= opendir (path
);
3060 while ((entry
= readdir (dir
)) != NULL
)
3066 fd
= atoi (entry
->d_name
);
3070 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
3071 if (stat (path
, &st
) != 0)
3073 if (!S_ISDIR (st
.st_mode
))
3076 if (statfs (path
, &stfs
) != 0)
3078 if (stfs
.f_type
!= SPUFS_MAGIC
)
3081 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
3083 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
3093 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
3094 object type, using the /proc file system. */
3096 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
3097 unsigned const char *writebuf
,
3098 CORE_ADDR offset
, int len
)
3100 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
3105 if (!writebuf
&& !readbuf
)
3113 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
3116 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
3117 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
3122 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
3129 ret
= write (fd
, writebuf
, (size_t) len
);
3131 ret
= read (fd
, readbuf
, (size_t) len
);
3137 static struct target_ops linux_target_ops
= {
3138 linux_create_inferior
,
3146 linux_fetch_registers
,
3147 linux_store_registers
,
3150 linux_look_up_symbols
,
3151 linux_request_interrupt
,
3155 linux_stopped_by_watchpoint
,
3156 linux_stopped_data_address
,
3157 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
3162 #ifdef USE_THREAD_DB
3163 thread_db_get_tls_address
,
3168 hostio_last_error_from_errno
,
3171 linux_supports_non_stop
,
3173 linux_start_non_stop
,
3174 linux_supports_multi_process
3178 linux_init_signals ()
3180 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
3181 to find what the cancel signal actually is. */
3182 signal (__SIGRTMIN
+1, SIG_IGN
);
3186 initialize_low (void)
3188 struct sigaction sigchld_action
;
3189 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
3190 set_target_ops (&linux_target_ops
);
3191 set_breakpoint_data (the_low_target
.breakpoint
,
3192 the_low_target
.breakpoint_len
);
3193 linux_init_signals ();
3194 linux_test_for_tracefork ();
3195 #ifdef HAVE_LINUX_REGSETS
3196 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
3198 disabled_regsets
= xmalloc (num_regsets
);
3201 sigchld_action
.sa_handler
= sigchld_handler
;
3202 sigemptyset (&sigchld_action
.sa_mask
);
3203 sigchld_action
.sa_flags
= SA_RESTART
;
3204 sigaction (SIGCHLD
, &sigchld_action
, NULL
);