1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-1996, 1998-2012 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "linux-osdata.h"
25 #include <sys/param.h>
26 #include <sys/ptrace.h>
27 #include "linux-ptrace.h"
28 #include "linux-procfs.h"
30 #include <sys/ioctl.h>
36 #include <sys/syscall.h>
40 #include <sys/types.h>
46 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
47 then ELFMAG0 will have been defined. If it didn't get included by
48 gdb_proc_service.h then including it will likely introduce a duplicate
49 definition of elf_fpregset_t. */
54 #define SPUFS_MAGIC 0x23c9b64e
57 #ifdef HAVE_PERSONALITY
58 # include <sys/personality.h>
59 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
60 # define ADDR_NO_RANDOMIZE 0x0040000
69 #define W_STOPCODE(sig) ((sig) << 8 | 0x7f)
72 /* This is the kernel's hard limit. Not to be confused with
79 #if !(defined(__UCLIBC_HAS_MMU__) || defined(__ARCH_HAS_MMU__))
84 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
85 representation of the thread ID.
87 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
88 the same as the LWP ID.
90 ``all_processes'' is keyed by the "overall process ID", which
91 GNU/Linux calls tgid, "thread group ID". */
93 struct inferior_list all_lwps
;
95 /* A list of all unknown processes which receive stop signals. Some other
96 process will presumably claim each of these as forked children
99 struct inferior_list stopped_pids
;
101 /* FIXME this is a bit of a hack, and could be removed. */
102 int stopping_threads
;
104 /* FIXME make into a target method? */
105 int using_threads
= 1;
107 /* True if we're presently stabilizing threads (moving them out of
109 static int stabilizing_threads
;
111 /* This flag is true iff we've just created or attached to our first
112 inferior but it has not stopped yet. As soon as it does, we need
113 to call the low target's arch_setup callback. Doing this only on
114 the first inferior avoids reinializing the architecture on every
115 inferior, and avoids messing with the register caches of the
116 already running inferiors. NOTE: this assumes all inferiors under
117 control of gdbserver have the same architecture. */
118 static int new_inferior
;
120 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
121 int step
, int signal
, siginfo_t
*info
);
122 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
123 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
124 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
125 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
126 static void *add_lwp (ptid_t ptid
);
127 static int linux_stopped_by_watchpoint (void);
128 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
129 static void proceed_all_lwps (void);
130 static int finish_step_over (struct lwp_info
*lwp
);
131 static CORE_ADDR
get_stop_pc (struct lwp_info
*lwp
);
132 static int kill_lwp (unsigned long lwpid
, int signo
);
133 static void linux_enable_event_reporting (int pid
);
135 /* True if the low target can hardware single-step. Such targets
136 don't need a BREAKPOINT_REINSERT_ADDR callback. */
139 can_hardware_single_step (void)
141 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
144 /* True if the low target supports memory breakpoints. If so, we'll
145 have a GET_PC implementation. */
148 supports_breakpoints (void)
150 return (the_low_target
.get_pc
!= NULL
);
153 /* Returns true if this target can support fast tracepoints. This
154 does not mean that the in-process agent has been loaded in the
158 supports_fast_tracepoints (void)
160 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
163 struct pending_signals
167 struct pending_signals
*prev
;
170 #define PTRACE_ARG3_TYPE void *
171 #define PTRACE_ARG4_TYPE void *
172 #define PTRACE_XFER_TYPE long
174 #ifdef HAVE_LINUX_REGSETS
175 static char *disabled_regsets
;
176 static int num_regsets
;
179 /* The read/write ends of the pipe registered as waitable file in the
181 static int linux_event_pipe
[2] = { -1, -1 };
183 /* True if we're currently in async mode. */
184 #define target_is_async_p() (linux_event_pipe[0] != -1)
186 static void send_sigstop (struct lwp_info
*lwp
);
187 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
189 /* Return non-zero if HEADER is a 64-bit ELF file. */
192 elf_64_header_p (const Elf64_Ehdr
*header
)
194 return (header
->e_ident
[EI_MAG0
] == ELFMAG0
195 && header
->e_ident
[EI_MAG1
] == ELFMAG1
196 && header
->e_ident
[EI_MAG2
] == ELFMAG2
197 && header
->e_ident
[EI_MAG3
] == ELFMAG3
198 && header
->e_ident
[EI_CLASS
] == ELFCLASS64
);
201 /* Return non-zero if FILE is a 64-bit ELF file,
202 zero if the file is not a 64-bit ELF file,
203 and -1 if the file is not accessible or doesn't exist. */
206 elf_64_file_p (const char *file
)
211 fd
= open (file
, O_RDONLY
);
215 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
222 return elf_64_header_p (&header
);
225 /* Accepts an integer PID; Returns true if the executable PID is
226 running is a 64-bit ELF file.. */
229 linux_pid_exe_is_elf_64_file (int pid
)
231 char file
[MAXPATHLEN
];
233 sprintf (file
, "/proc/%d/exe", pid
);
234 return elf_64_file_p (file
);
238 delete_lwp (struct lwp_info
*lwp
)
240 remove_thread (get_lwp_thread (lwp
));
241 remove_inferior (&all_lwps
, &lwp
->head
);
242 free (lwp
->arch_private
);
246 /* Add a process to the common process list, and set its private
249 static struct process_info
*
250 linux_add_process (int pid
, int attached
)
252 struct process_info
*proc
;
254 /* Is this the first process? If so, then set the arch. */
255 if (all_processes
.head
== NULL
)
258 proc
= add_process (pid
, attached
);
259 proc
->private = xcalloc (1, sizeof (*proc
->private));
261 if (the_low_target
.new_process
!= NULL
)
262 proc
->private->arch_private
= the_low_target
.new_process ();
267 /* Wrapper function for waitpid which handles EINTR, and emulates
268 __WALL for systems where that is not available. */
271 my_waitpid (int pid
, int *status
, int flags
)
276 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
280 sigset_t block_mask
, org_mask
, wake_mask
;
283 wnohang
= (flags
& WNOHANG
) != 0;
284 flags
&= ~(__WALL
| __WCLONE
);
287 /* Block all signals while here. This avoids knowing about
288 LinuxThread's signals. */
289 sigfillset (&block_mask
);
290 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
292 /* ... except during the sigsuspend below. */
293 sigemptyset (&wake_mask
);
297 /* Since all signals are blocked, there's no need to check
299 ret
= waitpid (pid
, status
, flags
);
302 if (ret
== -1 && out_errno
!= ECHILD
)
307 if (flags
& __WCLONE
)
309 /* We've tried both flavors now. If WNOHANG is set,
310 there's nothing else to do, just bail out. */
315 fprintf (stderr
, "blocking\n");
317 /* Block waiting for signals. */
318 sigsuspend (&wake_mask
);
324 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
329 ret
= waitpid (pid
, status
, flags
);
330 while (ret
== -1 && errno
== EINTR
);
335 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
336 pid
, flags
, status
? *status
: -1, ret
);
342 /* Handle a GNU/Linux extended wait response. If we see a clone
343 event, we need to add the new LWP to our list (and not report the
344 trap to higher layers). */
347 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
349 int event
= wstat
>> 16;
350 struct lwp_info
*new_lwp
;
352 if (event
== PTRACE_EVENT_CLONE
)
355 unsigned long new_pid
;
356 int ret
, status
= W_STOPCODE (SIGSTOP
);
358 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), 0, &new_pid
);
360 /* If we haven't already seen the new PID stop, wait for it now. */
361 if (! pull_pid_from_list (&stopped_pids
, new_pid
))
363 /* The new child has a pending SIGSTOP. We can't affect it until it
364 hits the SIGSTOP, but we're already attached. */
366 ret
= my_waitpid (new_pid
, &status
, __WALL
);
369 perror_with_name ("waiting for new child");
370 else if (ret
!= new_pid
)
371 warning ("wait returned unexpected PID %d", ret
);
372 else if (!WIFSTOPPED (status
))
373 warning ("wait returned unexpected status 0x%x", status
);
376 linux_enable_event_reporting (new_pid
);
378 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
379 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
380 add_thread (ptid
, new_lwp
);
382 /* Either we're going to immediately resume the new thread
383 or leave it stopped. linux_resume_one_lwp is a nop if it
384 thinks the thread is currently running, so set this first
385 before calling linux_resume_one_lwp. */
386 new_lwp
->stopped
= 1;
388 /* Normally we will get the pending SIGSTOP. But in some cases
389 we might get another signal delivered to the group first.
390 If we do get another signal, be sure not to lose it. */
391 if (WSTOPSIG (status
) == SIGSTOP
)
393 if (stopping_threads
)
394 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
396 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
400 new_lwp
->stop_expected
= 1;
402 if (stopping_threads
)
404 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
405 new_lwp
->status_pending_p
= 1;
406 new_lwp
->status_pending
= status
;
409 /* Pass the signal on. This is what GDB does - except
410 shouldn't we really report it instead? */
411 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
414 /* Always resume the current thread. If we are stopping
415 threads, it will have a pending SIGSTOP; we may as well
417 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
421 /* Return the PC as read from the regcache of LWP, without any
425 get_pc (struct lwp_info
*lwp
)
427 struct thread_info
*saved_inferior
;
428 struct regcache
*regcache
;
431 if (the_low_target
.get_pc
== NULL
)
434 saved_inferior
= current_inferior
;
435 current_inferior
= get_lwp_thread (lwp
);
437 regcache
= get_thread_regcache (current_inferior
, 1);
438 pc
= (*the_low_target
.get_pc
) (regcache
);
441 fprintf (stderr
, "pc is 0x%lx\n", (long) pc
);
443 current_inferior
= saved_inferior
;
447 /* This function should only be called if LWP got a SIGTRAP.
448 The SIGTRAP could mean several things.
450 On i386, where decr_pc_after_break is non-zero:
451 If we were single-stepping this process using PTRACE_SINGLESTEP,
452 we will get only the one SIGTRAP (even if the instruction we
453 stepped over was a breakpoint). The value of $eip will be the
455 If we continue the process using PTRACE_CONT, we will get a
456 SIGTRAP when we hit a breakpoint. The value of $eip will be
457 the instruction after the breakpoint (i.e. needs to be
458 decremented). If we report the SIGTRAP to GDB, we must also
459 report the undecremented PC. If we cancel the SIGTRAP, we
460 must resume at the decremented PC.
462 (Presumably, not yet tested) On a non-decr_pc_after_break machine
463 with hardware or kernel single-step:
464 If we single-step over a breakpoint instruction, our PC will
465 point at the following instruction. If we continue and hit a
466 breakpoint instruction, our PC will point at the breakpoint
470 get_stop_pc (struct lwp_info
*lwp
)
474 if (the_low_target
.get_pc
== NULL
)
477 stop_pc
= get_pc (lwp
);
479 if (WSTOPSIG (lwp
->last_status
) == SIGTRAP
481 && !lwp
->stopped_by_watchpoint
482 && lwp
->last_status
>> 16 == 0)
483 stop_pc
-= the_low_target
.decr_pc_after_break
;
486 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
492 add_lwp (ptid_t ptid
)
494 struct lwp_info
*lwp
;
496 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
497 memset (lwp
, 0, sizeof (*lwp
));
501 if (the_low_target
.new_thread
!= NULL
)
502 lwp
->arch_private
= the_low_target
.new_thread ();
504 add_inferior_to_list (&all_lwps
, &lwp
->head
);
509 /* Start an inferior process and returns its pid.
510 ALLARGS is a vector of program-name and args. */
513 linux_create_inferior (char *program
, char **allargs
)
515 #ifdef HAVE_PERSONALITY
516 int personality_orig
= 0, personality_set
= 0;
518 struct lwp_info
*new_lwp
;
522 #ifdef HAVE_PERSONALITY
523 if (disable_randomization
)
526 personality_orig
= personality (0xffffffff);
527 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
530 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
532 if (errno
!= 0 || (personality_set
533 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
534 warning ("Error disabling address space randomization: %s",
539 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
545 perror_with_name ("fork");
549 ptrace (PTRACE_TRACEME
, 0, 0, 0);
551 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
552 signal (__SIGRTMIN
+ 1, SIG_DFL
);
557 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
558 stdout to stderr so that inferior i/o doesn't corrupt the connection.
559 Also, redirect stdin to /dev/null. */
560 if (remote_connection_is_stdio ())
563 open ("/dev/null", O_RDONLY
);
565 if (write (2, "stdin/stdout redirected\n",
566 sizeof ("stdin/stdout redirected\n") - 1) < 0)
567 /* Errors ignored. */;
570 execv (program
, allargs
);
572 execvp (program
, allargs
);
574 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
580 #ifdef HAVE_PERSONALITY
584 personality (personality_orig
);
586 warning ("Error restoring address space randomization: %s",
591 linux_add_process (pid
, 0);
593 ptid
= ptid_build (pid
, pid
, 0);
594 new_lwp
= add_lwp (ptid
);
595 add_thread (ptid
, new_lwp
);
596 new_lwp
->must_set_ptrace_flags
= 1;
601 /* Attach to an inferior process. */
604 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
607 struct lwp_info
*new_lwp
;
609 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) != 0)
613 /* If we fail to attach to an LWP, just warn. */
614 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
615 strerror (errno
), errno
);
620 /* If we fail to attach to a process, report an error. */
621 error ("Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
622 strerror (errno
), errno
);
626 /* If lwp is the tgid, we handle adding existing threads later.
627 Otherwise we just add lwp without bothering about any other
629 ptid
= ptid_build (lwpid
, lwpid
, 0);
632 /* Note that extracting the pid from the current inferior is
633 safe, since we're always called in the context of the same
634 process as this new thread. */
635 int pid
= pid_of (get_thread_lwp (current_inferior
));
636 ptid
= ptid_build (pid
, lwpid
, 0);
639 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
640 add_thread (ptid
, new_lwp
);
642 /* We need to wait for SIGSTOP before being able to make the next
643 ptrace call on this LWP. */
644 new_lwp
->must_set_ptrace_flags
= 1;
646 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
649 There are several cases to consider here:
651 1) gdbserver has already attached to the process and is being notified
652 of a new thread that is being created.
653 In this case we should ignore that SIGSTOP and resume the
654 process. This is handled below by setting stop_expected = 1,
655 and the fact that add_thread sets last_resume_kind ==
658 2) This is the first thread (the process thread), and we're attaching
659 to it via attach_inferior.
660 In this case we want the process thread to stop.
661 This is handled by having linux_attach set last_resume_kind ==
662 resume_stop after we return.
664 If the pid we are attaching to is also the tgid, we attach to and
665 stop all the existing threads. Otherwise, we attach to pid and
666 ignore any other threads in the same group as this pid.
668 3) GDB is connecting to gdbserver and is requesting an enumeration of all
670 In this case we want the thread to stop.
671 FIXME: This case is currently not properly handled.
672 We should wait for the SIGSTOP but don't. Things work apparently
673 because enough time passes between when we ptrace (ATTACH) and when
674 gdb makes the next ptrace call on the thread.
676 On the other hand, if we are currently trying to stop all threads, we
677 should treat the new thread as if we had sent it a SIGSTOP. This works
678 because we are guaranteed that the add_lwp call above added us to the
679 end of the list, and so the new thread has not yet reached
680 wait_for_sigstop (but will). */
681 new_lwp
->stop_expected
= 1;
685 linux_attach_lwp (unsigned long lwpid
)
687 linux_attach_lwp_1 (lwpid
, 0);
690 /* Attach to PID. If PID is the tgid, attach to it and all
694 linux_attach (unsigned long pid
)
696 /* Attach to PID. We will check for other threads
698 linux_attach_lwp_1 (pid
, 1);
699 linux_add_process (pid
, 1);
703 struct thread_info
*thread
;
705 /* Don't ignore the initial SIGSTOP if we just attached to this
706 process. It will be collected by wait shortly. */
707 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
708 thread
->last_resume_kind
= resume_stop
;
711 if (linux_proc_get_tgid (pid
) == pid
)
716 sprintf (pathname
, "/proc/%ld/task", pid
);
718 dir
= opendir (pathname
);
722 fprintf (stderr
, "Could not open /proc/%ld/task.\n", pid
);
727 /* At this point we attached to the tgid. Scan the task for
730 int new_threads_found
;
734 while (iterations
< 2)
736 new_threads_found
= 0;
737 /* Add all the other threads. While we go through the
738 threads, new threads may be spawned. Cycle through
739 the list of threads until we have done two iterations without
740 finding new threads. */
741 while ((dp
= readdir (dir
)) != NULL
)
744 lwp
= strtoul (dp
->d_name
, NULL
, 10);
746 /* Is this a new thread? */
748 && find_thread_ptid (ptid_build (pid
, lwp
, 0)) == NULL
)
750 linux_attach_lwp_1 (lwp
, 0);
755 Found and attached to new lwp %ld\n", lwp
);
759 if (!new_threads_found
)
780 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
782 struct counter
*counter
= args
;
784 if (ptid_get_pid (entry
->id
) == counter
->pid
)
786 if (++counter
->count
> 1)
794 last_thread_of_process_p (struct thread_info
*thread
)
796 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
797 int pid
= ptid_get_pid (ptid
);
798 struct counter counter
= { pid
, 0 };
800 return (find_inferior (&all_threads
,
801 second_thread_of_pid_p
, &counter
) == NULL
);
804 /* Kill the inferior lwp. */
807 linux_kill_one_lwp (struct inferior_list_entry
*entry
, void *args
)
809 struct thread_info
*thread
= (struct thread_info
*) entry
;
810 struct lwp_info
*lwp
= get_thread_lwp (thread
);
812 int pid
= * (int *) args
;
814 if (ptid_get_pid (entry
->id
) != pid
)
817 /* We avoid killing the first thread here, because of a Linux kernel (at
818 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
819 the children get a chance to be reaped, it will remain a zombie
822 if (lwpid_of (lwp
) == pid
)
825 fprintf (stderr
, "lkop: is last of process %s\n",
826 target_pid_to_str (entry
->id
));
832 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
834 /* Make sure it died. The loop is most likely unnecessary. */
835 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
836 } while (pid
> 0 && WIFSTOPPED (wstat
));
844 struct process_info
*process
;
845 struct lwp_info
*lwp
;
849 process
= find_process_pid (pid
);
853 /* If we're killing a running inferior, make sure it is stopped
854 first, as PTRACE_KILL will not work otherwise. */
855 stop_all_lwps (0, NULL
);
857 find_inferior (&all_threads
, linux_kill_one_lwp
, &pid
);
859 /* See the comment in linux_kill_one_lwp. We did not kill the first
860 thread in the list, so do so now. */
861 lwp
= find_lwp_pid (pid_to_ptid (pid
));
866 fprintf (stderr
, "lk_1: cannot find lwp %ld, for pid: %d\n",
867 lwpid_of (lwp
), pid
);
872 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
873 lwpid_of (lwp
), pid
);
877 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
879 /* Make sure it died. The loop is most likely unnecessary. */
880 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
881 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
884 the_target
->mourn (process
);
886 /* Since we presently can only stop all lwps of all processes, we
887 need to unstop lwps of other processes. */
888 unstop_all_lwps (0, NULL
);
893 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
895 struct thread_info
*thread
= (struct thread_info
*) entry
;
896 struct lwp_info
*lwp
= get_thread_lwp (thread
);
897 int pid
= * (int *) args
;
899 if (ptid_get_pid (entry
->id
) != pid
)
902 /* If this process is stopped but is expecting a SIGSTOP, then make
903 sure we take care of that now. This isn't absolutely guaranteed
904 to collect the SIGSTOP, but is fairly likely to. */
905 if (lwp
->stop_expected
)
908 /* Clear stop_expected, so that the SIGSTOP will be reported. */
909 lwp
->stop_expected
= 0;
910 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
911 linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
914 /* Flush any pending changes to the process's registers. */
915 regcache_invalidate_one ((struct inferior_list_entry
*)
916 get_lwp_thread (lwp
));
918 /* Finally, let it resume. */
919 if (the_low_target
.prepare_to_resume
!= NULL
)
920 the_low_target
.prepare_to_resume (lwp
);
921 ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0, 0);
928 linux_detach (int pid
)
930 struct process_info
*process
;
932 process
= find_process_pid (pid
);
936 /* Stop all threads before detaching. First, ptrace requires that
937 the thread is stopped to sucessfully detach. Second, thread_db
938 may need to uninstall thread event breakpoints from memory, which
939 only works with a stopped process anyway. */
940 stop_all_lwps (0, NULL
);
943 thread_db_detach (process
);
946 /* Stabilize threads (move out of jump pads). */
947 stabilize_threads ();
949 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
951 the_target
->mourn (process
);
953 /* Since we presently can only stop all lwps of all processes, we
954 need to unstop lwps of other processes. */
955 unstop_all_lwps (0, NULL
);
959 /* Remove all LWPs that belong to process PROC from the lwp list. */
962 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
964 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
965 struct process_info
*process
= proc
;
967 if (pid_of (lwp
) == pid_of (process
))
974 linux_mourn (struct process_info
*process
)
976 struct process_info_private
*priv
;
979 thread_db_mourn (process
);
982 find_inferior (&all_lwps
, delete_lwp_callback
, process
);
984 /* Freeing all private data. */
985 priv
= process
->private;
986 free (priv
->arch_private
);
988 process
->private = NULL
;
990 remove_process (process
);
999 ret
= my_waitpid (pid
, &status
, 0);
1000 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1002 } while (ret
!= -1 || errno
!= ECHILD
);
1005 /* Return nonzero if the given thread is still alive. */
1007 linux_thread_alive (ptid_t ptid
)
1009 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1011 /* We assume we always know if a thread exits. If a whole process
1012 exited but we still haven't been able to report it to GDB, we'll
1013 hold on to the last lwp of the dead process. */
1020 /* Return 1 if this lwp has an interesting status pending. */
1022 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1024 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1025 ptid_t ptid
= * (ptid_t
*) arg
;
1026 struct thread_info
*thread
;
1028 /* Check if we're only interested in events from a specific process
1030 if (!ptid_equal (minus_one_ptid
, ptid
)
1031 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
1034 thread
= get_lwp_thread (lwp
);
1036 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1037 report any status pending the LWP may have. */
1038 if (thread
->last_resume_kind
== resume_stop
1039 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1042 return lwp
->status_pending_p
;
1046 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1048 ptid_t ptid
= *(ptid_t
*) data
;
1051 if (ptid_get_lwp (ptid
) != 0)
1052 lwp
= ptid_get_lwp (ptid
);
1054 lwp
= ptid_get_pid (ptid
);
1056 if (ptid_get_lwp (entry
->id
) == lwp
)
1063 find_lwp_pid (ptid_t ptid
)
1065 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
1068 static struct lwp_info
*
1069 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
1072 int to_wait_for
= -1;
1073 struct lwp_info
*child
= NULL
;
1076 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1078 if (ptid_equal (ptid
, minus_one_ptid
))
1079 to_wait_for
= -1; /* any child */
1081 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1087 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1088 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1091 perror_with_name ("waitpid");
1094 && (!WIFSTOPPED (*wstatp
)
1095 || (WSTOPSIG (*wstatp
) != 32
1096 && WSTOPSIG (*wstatp
) != 33)))
1097 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1099 child
= find_lwp_pid (pid_to_ptid (ret
));
1101 /* If we didn't find a process, one of two things presumably happened:
1102 - A process we started and then detached from has exited. Ignore it.
1103 - A process we are controlling has forked and the new child's stop
1104 was reported to us by the kernel. Save its PID. */
1105 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1107 add_pid_to_list (&stopped_pids
, ret
);
1110 else if (child
== NULL
)
1115 child
->last_status
= *wstatp
;
1117 /* Architecture-specific setup after inferior is running.
1118 This needs to happen after we have attached to the inferior
1119 and it is stopped for the first time, but before we access
1120 any inferior registers. */
1123 the_low_target
.arch_setup ();
1124 #ifdef HAVE_LINUX_REGSETS
1125 memset (disabled_regsets
, 0, num_regsets
);
1130 /* Fetch the possibly triggered data watchpoint info and store it in
1133 On some archs, like x86, that use debug registers to set
1134 watchpoints, it's possible that the way to know which watched
1135 address trapped, is to check the register that is used to select
1136 which address to watch. Problem is, between setting the
1137 watchpoint and reading back which data address trapped, the user
1138 may change the set of watchpoints, and, as a consequence, GDB
1139 changes the debug registers in the inferior. To avoid reading
1140 back a stale stopped-data-address when that happens, we cache in
1141 LP the fact that a watchpoint trapped, and the corresponding data
1142 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1143 changes the debug registers meanwhile, we have the cached data we
1146 if (WIFSTOPPED (*wstatp
) && WSTOPSIG (*wstatp
) == SIGTRAP
)
1148 if (the_low_target
.stopped_by_watchpoint
== NULL
)
1150 child
->stopped_by_watchpoint
= 0;
1154 struct thread_info
*saved_inferior
;
1156 saved_inferior
= current_inferior
;
1157 current_inferior
= get_lwp_thread (child
);
1159 child
->stopped_by_watchpoint
1160 = the_low_target
.stopped_by_watchpoint ();
1162 if (child
->stopped_by_watchpoint
)
1164 if (the_low_target
.stopped_data_address
!= NULL
)
1165 child
->stopped_data_address
1166 = the_low_target
.stopped_data_address ();
1168 child
->stopped_data_address
= 0;
1171 current_inferior
= saved_inferior
;
1175 /* Store the STOP_PC, with adjustment applied. This depends on the
1176 architecture being defined already (so that CHILD has a valid
1177 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1179 if (WIFSTOPPED (*wstatp
))
1180 child
->stop_pc
= get_stop_pc (child
);
1183 && WIFSTOPPED (*wstatp
)
1184 && the_low_target
.get_pc
!= NULL
)
1186 struct thread_info
*saved_inferior
= current_inferior
;
1187 struct regcache
*regcache
;
1190 current_inferior
= get_lwp_thread (child
);
1191 regcache
= get_thread_regcache (current_inferior
, 1);
1192 pc
= (*the_low_target
.get_pc
) (regcache
);
1193 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1194 current_inferior
= saved_inferior
;
1200 /* This function should only be called if the LWP got a SIGTRAP.
1202 Handle any tracepoint steps or hits. Return true if a tracepoint
1203 event was handled, 0 otherwise. */
1206 handle_tracepoints (struct lwp_info
*lwp
)
1208 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1209 int tpoint_related_event
= 0;
1211 /* If this tracepoint hit causes a tracing stop, we'll immediately
1212 uninsert tracepoints. To do this, we temporarily pause all
1213 threads, unpatch away, and then unpause threads. We need to make
1214 sure the unpausing doesn't resume LWP too. */
1217 /* And we need to be sure that any all-threads-stopping doesn't try
1218 to move threads out of the jump pads, as it could deadlock the
1219 inferior (LWP could be in the jump pad, maybe even holding the
1222 /* Do any necessary step collect actions. */
1223 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1225 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1227 /* See if we just hit a tracepoint and do its main collect
1229 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1233 gdb_assert (lwp
->suspended
== 0);
1234 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1236 if (tpoint_related_event
)
1239 fprintf (stderr
, "got a tracepoint event\n");
1246 /* Convenience wrapper. Returns true if LWP is presently collecting a
1250 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1251 struct fast_tpoint_collect_status
*status
)
1253 CORE_ADDR thread_area
;
1255 if (the_low_target
.get_thread_area
== NULL
)
1258 /* Get the thread area address. This is used to recognize which
1259 thread is which when tracing with the in-process agent library.
1260 We don't read anything from the address, and treat it as opaque;
1261 it's the address itself that we assume is unique per-thread. */
1262 if ((*the_low_target
.get_thread_area
) (lwpid_of (lwp
), &thread_area
) == -1)
1265 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1268 /* The reason we resume in the caller, is because we want to be able
1269 to pass lwp->status_pending as WSTAT, and we need to clear
1270 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1271 refuses to resume. */
1274 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1276 struct thread_info
*saved_inferior
;
1278 saved_inferior
= current_inferior
;
1279 current_inferior
= get_lwp_thread (lwp
);
1282 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1283 && supports_fast_tracepoints ()
1284 && in_process_agent_loaded ())
1286 struct fast_tpoint_collect_status status
;
1291 Checking whether LWP %ld needs to move out of the jump pad.\n",
1294 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1297 || (WSTOPSIG (*wstat
) != SIGILL
1298 && WSTOPSIG (*wstat
) != SIGFPE
1299 && WSTOPSIG (*wstat
) != SIGSEGV
1300 && WSTOPSIG (*wstat
) != SIGBUS
))
1302 lwp
->collecting_fast_tracepoint
= r
;
1306 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1308 /* Haven't executed the original instruction yet.
1309 Set breakpoint there, and wait till it's hit,
1310 then single-step until exiting the jump pad. */
1311 lwp
->exit_jump_pad_bkpt
1312 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1317 Checking whether LWP %ld needs to move out of the jump pad...it does\n",
1319 current_inferior
= saved_inferior
;
1326 /* If we get a synchronous signal while collecting, *and*
1327 while executing the (relocated) original instruction,
1328 reset the PC to point at the tpoint address, before
1329 reporting to GDB. Otherwise, it's an IPA lib bug: just
1330 report the signal to GDB, and pray for the best. */
1332 lwp
->collecting_fast_tracepoint
= 0;
1335 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1336 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1339 struct regcache
*regcache
;
1341 /* The si_addr on a few signals references the address
1342 of the faulting instruction. Adjust that as
1344 if ((WSTOPSIG (*wstat
) == SIGILL
1345 || WSTOPSIG (*wstat
) == SIGFPE
1346 || WSTOPSIG (*wstat
) == SIGBUS
1347 || WSTOPSIG (*wstat
) == SIGSEGV
)
1348 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &info
) == 0
1349 /* Final check just to make sure we don't clobber
1350 the siginfo of non-kernel-sent signals. */
1351 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1353 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1354 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &info
);
1357 regcache
= get_thread_regcache (get_lwp_thread (lwp
), 1);
1358 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1359 lwp
->stop_pc
= status
.tpoint_addr
;
1361 /* Cancel any fast tracepoint lock this thread was
1363 force_unlock_trace_buffer ();
1366 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1370 "Cancelling fast exit-jump-pad: removing bkpt. "
1371 "stopping all threads momentarily.\n");
1373 stop_all_lwps (1, lwp
);
1374 cancel_breakpoints ();
1376 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1377 lwp
->exit_jump_pad_bkpt
= NULL
;
1379 unstop_all_lwps (1, lwp
);
1381 gdb_assert (lwp
->suspended
>= 0);
1388 Checking whether LWP %ld needs to move out of the jump pad...no\n",
1391 current_inferior
= saved_inferior
;
1395 /* Enqueue one signal in the "signals to report later when out of the
1399 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1401 struct pending_signals
*p_sig
;
1405 Deferring signal %d for LWP %ld.\n", WSTOPSIG (*wstat
), lwpid_of (lwp
));
1409 struct pending_signals
*sig
;
1411 for (sig
= lwp
->pending_signals_to_report
;
1415 " Already queued %d\n",
1418 fprintf (stderr
, " (no more currently queued signals)\n");
1421 /* Don't enqueue non-RT signals if they are already in the deferred
1422 queue. (SIGSTOP being the easiest signal to see ending up here
1424 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1426 struct pending_signals
*sig
;
1428 for (sig
= lwp
->pending_signals_to_report
;
1432 if (sig
->signal
== WSTOPSIG (*wstat
))
1436 "Not requeuing already queued non-RT signal %d"
1445 p_sig
= xmalloc (sizeof (*p_sig
));
1446 p_sig
->prev
= lwp
->pending_signals_to_report
;
1447 p_sig
->signal
= WSTOPSIG (*wstat
);
1448 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1449 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
1451 lwp
->pending_signals_to_report
= p_sig
;
1454 /* Dequeue one signal from the "signals to report later when out of
1455 the jump pad" list. */
1458 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1460 if (lwp
->pending_signals_to_report
!= NULL
)
1462 struct pending_signals
**p_sig
;
1464 p_sig
= &lwp
->pending_signals_to_report
;
1465 while ((*p_sig
)->prev
!= NULL
)
1466 p_sig
= &(*p_sig
)->prev
;
1468 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1469 if ((*p_sig
)->info
.si_signo
!= 0)
1470 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
1475 fprintf (stderr
, "Reporting deferred signal %d for LWP %ld.\n",
1476 WSTOPSIG (*wstat
), lwpid_of (lwp
));
1480 struct pending_signals
*sig
;
1482 for (sig
= lwp
->pending_signals_to_report
;
1486 " Still queued %d\n",
1489 fprintf (stderr
, " (no more queued signals)\n");
1498 /* Arrange for a breakpoint to be hit again later. We don't keep the
1499 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1500 will handle the current event, eventually we will resume this LWP,
1501 and this breakpoint will trap again. */
1504 cancel_breakpoint (struct lwp_info
*lwp
)
1506 struct thread_info
*saved_inferior
;
1508 /* There's nothing to do if we don't support breakpoints. */
1509 if (!supports_breakpoints ())
1512 /* breakpoint_at reads from current inferior. */
1513 saved_inferior
= current_inferior
;
1514 current_inferior
= get_lwp_thread (lwp
);
1516 if ((*the_low_target
.breakpoint_at
) (lwp
->stop_pc
))
1520 "CB: Push back breakpoint for %s\n",
1521 target_pid_to_str (ptid_of (lwp
)));
1523 /* Back up the PC if necessary. */
1524 if (the_low_target
.decr_pc_after_break
)
1526 struct regcache
*regcache
1527 = get_thread_regcache (current_inferior
, 1);
1528 (*the_low_target
.set_pc
) (regcache
, lwp
->stop_pc
);
1531 current_inferior
= saved_inferior
;
1538 "CB: No breakpoint found at %s for [%s]\n",
1539 paddress (lwp
->stop_pc
),
1540 target_pid_to_str (ptid_of (lwp
)));
1543 current_inferior
= saved_inferior
;
1547 /* When the event-loop is doing a step-over, this points at the thread
1549 ptid_t step_over_bkpt
;
1551 /* Wait for an event from child PID. If PID is -1, wait for any
1552 child. Store the stop status through the status pointer WSTAT.
1553 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1554 event was found and OPTIONS contains WNOHANG. Return the PID of
1555 the stopped child otherwise. */
1558 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1560 struct lwp_info
*event_child
, *requested_child
;
1564 requested_child
= NULL
;
1566 /* Check for a lwp with a pending status. */
1568 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
1570 event_child
= (struct lwp_info
*)
1571 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1572 if (debug_threads
&& event_child
)
1573 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1577 requested_child
= find_lwp_pid (ptid
);
1579 if (!stopping_threads
1580 && requested_child
->status_pending_p
1581 && requested_child
->collecting_fast_tracepoint
)
1583 enqueue_one_deferred_signal (requested_child
,
1584 &requested_child
->status_pending
);
1585 requested_child
->status_pending_p
= 0;
1586 requested_child
->status_pending
= 0;
1587 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
1590 if (requested_child
->suspended
1591 && requested_child
->status_pending_p
)
1592 fatal ("requesting an event out of a suspended child?");
1594 if (requested_child
->status_pending_p
)
1595 event_child
= requested_child
;
1598 if (event_child
!= NULL
)
1601 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1602 lwpid_of (event_child
), event_child
->status_pending
);
1603 *wstat
= event_child
->status_pending
;
1604 event_child
->status_pending_p
= 0;
1605 event_child
->status_pending
= 0;
1606 current_inferior
= get_lwp_thread (event_child
);
1607 return lwpid_of (event_child
);
1610 if (ptid_is_pid (ptid
))
1612 /* A request to wait for a specific tgid. This is not possible
1613 with waitpid, so instead, we wait for any child, and leave
1614 children we're not interested in right now with a pending
1615 status to report later. */
1616 wait_ptid
= minus_one_ptid
;
1621 /* We only enter this loop if no process has a pending wait status. Thus
1622 any action taken in response to a wait status inside this loop is
1623 responding as soon as we detect the status, not after any pending
1627 event_child
= linux_wait_for_lwp (wait_ptid
, wstat
, options
);
1629 if ((options
& WNOHANG
) && event_child
== NULL
)
1632 fprintf (stderr
, "WNOHANG set, no event found\n");
1636 if (event_child
== NULL
)
1637 error ("event from unknown child");
1639 if (ptid_is_pid (ptid
)
1640 && ptid_get_pid (ptid
) != ptid_get_pid (ptid_of (event_child
)))
1642 if (! WIFSTOPPED (*wstat
))
1643 mark_lwp_dead (event_child
, *wstat
);
1646 event_child
->status_pending_p
= 1;
1647 event_child
->status_pending
= *wstat
;
1652 current_inferior
= get_lwp_thread (event_child
);
1654 /* Check for thread exit. */
1655 if (! WIFSTOPPED (*wstat
))
1658 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1660 /* If the last thread is exiting, just return. */
1661 if (last_thread_of_process_p (current_inferior
))
1664 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1665 lwpid_of (event_child
));
1666 return lwpid_of (event_child
);
1671 current_inferior
= (struct thread_info
*) all_threads
.head
;
1673 fprintf (stderr
, "Current inferior is now %ld\n",
1674 lwpid_of (get_thread_lwp (current_inferior
)));
1678 current_inferior
= NULL
;
1680 fprintf (stderr
, "Current inferior is now <NULL>\n");
1683 /* If we were waiting for this particular child to do something...
1684 well, it did something. */
1685 if (requested_child
!= NULL
)
1687 int lwpid
= lwpid_of (event_child
);
1689 /* Cancel the step-over operation --- the thread that
1690 started it is gone. */
1691 if (finish_step_over (event_child
))
1692 unstop_all_lwps (1, event_child
);
1693 delete_lwp (event_child
);
1697 delete_lwp (event_child
);
1699 /* Wait for a more interesting event. */
1703 if (event_child
->must_set_ptrace_flags
)
1705 linux_enable_event_reporting (lwpid_of (event_child
));
1706 event_child
->must_set_ptrace_flags
= 0;
1709 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1710 && *wstat
>> 16 != 0)
1712 handle_extended_wait (event_child
, *wstat
);
1716 if (WIFSTOPPED (*wstat
)
1717 && WSTOPSIG (*wstat
) == SIGSTOP
1718 && event_child
->stop_expected
)
1723 fprintf (stderr
, "Expected stop.\n");
1724 event_child
->stop_expected
= 0;
1726 should_stop
= (current_inferior
->last_resume_kind
== resume_stop
1727 || stopping_threads
);
1731 linux_resume_one_lwp (event_child
,
1732 event_child
->stepping
, 0, NULL
);
1737 return lwpid_of (event_child
);
1744 /* Count the LWP's that have had events. */
1747 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
1749 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1750 struct thread_info
*thread
= get_lwp_thread (lp
);
1753 gdb_assert (count
!= NULL
);
1755 /* Count only resumed LWPs that have a SIGTRAP event pending that
1756 should be reported to GDB. */
1757 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1758 && thread
->last_resume_kind
!= resume_stop
1759 && lp
->status_pending_p
1760 && WIFSTOPPED (lp
->status_pending
)
1761 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1762 && !breakpoint_inserted_here (lp
->stop_pc
))
1768 /* Select the LWP (if any) that is currently being single-stepped. */
1771 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1773 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1774 struct thread_info
*thread
= get_lwp_thread (lp
);
1776 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1777 && thread
->last_resume_kind
== resume_step
1778 && lp
->status_pending_p
)
1784 /* Select the Nth LWP that has had a SIGTRAP event that should be
1788 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1790 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1791 struct thread_info
*thread
= get_lwp_thread (lp
);
1792 int *selector
= data
;
1794 gdb_assert (selector
!= NULL
);
1796 /* Select only resumed LWPs that have a SIGTRAP event pending. */
1797 if (thread
->last_resume_kind
!= resume_stop
1798 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1799 && lp
->status_pending_p
1800 && WIFSTOPPED (lp
->status_pending
)
1801 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1802 && !breakpoint_inserted_here (lp
->stop_pc
))
1803 if ((*selector
)-- == 0)
1810 cancel_breakpoints_callback (struct inferior_list_entry
*entry
, void *data
)
1812 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1813 struct thread_info
*thread
= get_lwp_thread (lp
);
1814 struct lwp_info
*event_lp
= data
;
1816 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
1820 /* If a LWP other than the LWP that we're reporting an event for has
1821 hit a GDB breakpoint (as opposed to some random trap signal),
1822 then just arrange for it to hit it again later. We don't keep
1823 the SIGTRAP status and don't forward the SIGTRAP signal to the
1824 LWP. We will handle the current event, eventually we will resume
1825 all LWPs, and this one will get its breakpoint trap again.
1827 If we do not do this, then we run the risk that the user will
1828 delete or disable the breakpoint, but the LWP will have already
1831 if (thread
->last_resume_kind
!= resume_stop
1832 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1833 && lp
->status_pending_p
1834 && WIFSTOPPED (lp
->status_pending
)
1835 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1837 && !lp
->stopped_by_watchpoint
1838 && cancel_breakpoint (lp
))
1839 /* Throw away the SIGTRAP. */
1840 lp
->status_pending_p
= 0;
1846 linux_cancel_breakpoints (void)
1848 find_inferior (&all_lwps
, cancel_breakpoints_callback
, NULL
);
1851 /* Select one LWP out of those that have events pending. */
1854 select_event_lwp (struct lwp_info
**orig_lp
)
1857 int random_selector
;
1858 struct lwp_info
*event_lp
;
1860 /* Give preference to any LWP that is being single-stepped. */
1862 = (struct lwp_info
*) find_inferior (&all_lwps
,
1863 select_singlestep_lwp_callback
, NULL
);
1864 if (event_lp
!= NULL
)
1868 "SEL: Select single-step %s\n",
1869 target_pid_to_str (ptid_of (event_lp
)));
1873 /* No single-stepping LWP. Select one at random, out of those
1874 which have had SIGTRAP events. */
1876 /* First see how many SIGTRAP events we have. */
1877 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
1879 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
1880 random_selector
= (int)
1881 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
1883 if (debug_threads
&& num_events
> 1)
1885 "SEL: Found %d SIGTRAP events, selecting #%d\n",
1886 num_events
, random_selector
);
1888 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
1889 select_event_lwp_callback
,
1893 if (event_lp
!= NULL
)
1895 /* Switch the event LWP. */
1896 *orig_lp
= event_lp
;
1900 /* Decrement the suspend count of an LWP. */
1903 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
1905 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1907 /* Ignore EXCEPT. */
1913 gdb_assert (lwp
->suspended
>= 0);
1917 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
1921 unsuspend_all_lwps (struct lwp_info
*except
)
1923 find_inferior (&all_lwps
, unsuspend_one_lwp
, except
);
1926 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
1927 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
1929 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
1930 static ptid_t
linux_wait_1 (ptid_t ptid
,
1931 struct target_waitstatus
*ourstatus
,
1932 int target_options
);
1934 /* Stabilize threads (move out of jump pads).
1936 If a thread is midway collecting a fast tracepoint, we need to
1937 finish the collection and move it out of the jump pad before
1938 reporting the signal.
1940 This avoids recursion while collecting (when a signal arrives
1941 midway, and the signal handler itself collects), which would trash
1942 the trace buffer. In case the user set a breakpoint in a signal
1943 handler, this avoids the backtrace showing the jump pad, etc..
1944 Most importantly, there are certain things we can't do safely if
1945 threads are stopped in a jump pad (or in its callee's). For
1948 - starting a new trace run. A thread still collecting the
1949 previous run, could trash the trace buffer when resumed. The trace
1950 buffer control structures would have been reset but the thread had
1951 no way to tell. The thread could even midway memcpy'ing to the
1952 buffer, which would mean that when resumed, it would clobber the
1953 trace buffer that had been set for a new run.
1955 - we can't rewrite/reuse the jump pads for new tracepoints
1956 safely. Say you do tstart while a thread is stopped midway while
1957 collecting. When the thread is later resumed, it finishes the
1958 collection, and returns to the jump pad, to execute the original
1959 instruction that was under the tracepoint jump at the time the
1960 older run had been started. If the jump pad had been rewritten
1961 since for something else in the new run, the thread would now
1962 execute the wrong / random instructions. */
1965 linux_stabilize_threads (void)
1967 struct thread_info
*save_inferior
;
1968 struct lwp_info
*lwp_stuck
;
1971 = (struct lwp_info
*) find_inferior (&all_lwps
,
1972 stuck_in_jump_pad_callback
, NULL
);
1973 if (lwp_stuck
!= NULL
)
1976 fprintf (stderr
, "can't stabilize, LWP %ld is stuck in jump pad\n",
1977 lwpid_of (lwp_stuck
));
1981 save_inferior
= current_inferior
;
1983 stabilizing_threads
= 1;
1986 for_each_inferior (&all_lwps
, move_out_of_jump_pad_callback
);
1988 /* Loop until all are stopped out of the jump pads. */
1989 while (find_inferior (&all_lwps
, lwp_running
, NULL
) != NULL
)
1991 struct target_waitstatus ourstatus
;
1992 struct lwp_info
*lwp
;
1995 /* Note that we go through the full wait even loop. While
1996 moving threads out of jump pad, we need to be able to step
1997 over internal breakpoints and such. */
1998 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2000 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2002 lwp
= get_thread_lwp (current_inferior
);
2007 if (ourstatus
.value
.sig
!= TARGET_SIGNAL_0
2008 || current_inferior
->last_resume_kind
== resume_stop
)
2010 wstat
= W_STOPCODE (target_signal_to_host (ourstatus
.value
.sig
));
2011 enqueue_one_deferred_signal (lwp
, &wstat
);
2016 find_inferior (&all_lwps
, unsuspend_one_lwp
, NULL
);
2018 stabilizing_threads
= 0;
2020 current_inferior
= save_inferior
;
2025 = (struct lwp_info
*) find_inferior (&all_lwps
,
2026 stuck_in_jump_pad_callback
, NULL
);
2027 if (lwp_stuck
!= NULL
)
2028 fprintf (stderr
, "couldn't stabilize, LWP %ld got stuck in jump pad\n",
2029 lwpid_of (lwp_stuck
));
2033 /* Wait for process, returns status. */
2036 linux_wait_1 (ptid_t ptid
,
2037 struct target_waitstatus
*ourstatus
, int target_options
)
2040 struct lwp_info
*event_child
;
2043 int step_over_finished
;
2044 int bp_explains_trap
;
2045 int maybe_internal_trap
;
2049 /* Translate generic target options into linux options. */
2051 if (target_options
& TARGET_WNOHANG
)
2055 bp_explains_trap
= 0;
2057 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2059 /* If we were only supposed to resume one thread, only wait for
2060 that thread - if it's still alive. If it died, however - which
2061 can happen if we're coming from the thread death case below -
2062 then we need to make sure we restart the other threads. We could
2063 pick a thread at random or restart all; restarting all is less
2066 && !ptid_equal (cont_thread
, null_ptid
)
2067 && !ptid_equal (cont_thread
, minus_one_ptid
))
2069 struct thread_info
*thread
;
2071 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
2074 /* No stepping, no signal - unless one is pending already, of course. */
2077 struct thread_resume resume_info
;
2078 resume_info
.thread
= minus_one_ptid
;
2079 resume_info
.kind
= resume_continue
;
2080 resume_info
.sig
= 0;
2081 linux_resume (&resume_info
, 1);
2087 if (ptid_equal (step_over_bkpt
, null_ptid
))
2088 pid
= linux_wait_for_event (ptid
, &w
, options
);
2092 fprintf (stderr
, "step_over_bkpt set [%s], doing a blocking wait\n",
2093 target_pid_to_str (step_over_bkpt
));
2094 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2097 if (pid
== 0) /* only if TARGET_WNOHANG */
2100 event_child
= get_thread_lwp (current_inferior
);
2102 /* If we are waiting for a particular child, and it exited,
2103 linux_wait_for_event will return its exit status. Similarly if
2104 the last child exited. If this is not the last child, however,
2105 do not report it as exited until there is a 'thread exited' response
2106 available in the remote protocol. Instead, just wait for another event.
2107 This should be safe, because if the thread crashed we will already
2108 have reported the termination signal to GDB; that should stop any
2109 in-progress stepping operations, etc.
2111 Report the exit status of the last thread to exit. This matches
2112 LinuxThreads' behavior. */
2114 if (last_thread_of_process_p (current_inferior
))
2116 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2120 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2121 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2125 "\nChild exited with retcode = %x \n",
2130 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2131 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
2135 "\nChild terminated with signal = %x \n",
2140 return ptid_of (event_child
);
2145 if (!WIFSTOPPED (w
))
2149 /* If this event was not handled before, and is not a SIGTRAP, we
2150 report it. SIGILL and SIGSEGV are also treated as traps in case
2151 a breakpoint is inserted at the current PC. If this target does
2152 not support internal breakpoints at all, we also report the
2153 SIGTRAP without further processing; it's of no concern to us. */
2155 = (supports_breakpoints ()
2156 && (WSTOPSIG (w
) == SIGTRAP
2157 || ((WSTOPSIG (w
) == SIGILL
2158 || WSTOPSIG (w
) == SIGSEGV
)
2159 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2161 if (maybe_internal_trap
)
2163 /* Handle anything that requires bookkeeping before deciding to
2164 report the event or continue waiting. */
2166 /* First check if we can explain the SIGTRAP with an internal
2167 breakpoint, or if we should possibly report the event to GDB.
2168 Do this before anything that may remove or insert a
2170 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2172 /* We have a SIGTRAP, possibly a step-over dance has just
2173 finished. If so, tweak the state machine accordingly,
2174 reinsert breakpoints and delete any reinsert (software
2175 single-step) breakpoints. */
2176 step_over_finished
= finish_step_over (event_child
);
2178 /* Now invoke the callbacks of any internal breakpoints there. */
2179 check_breakpoints (event_child
->stop_pc
);
2181 /* Handle tracepoint data collecting. This may overflow the
2182 trace buffer, and cause a tracing stop, removing
2184 trace_event
= handle_tracepoints (event_child
);
2186 if (bp_explains_trap
)
2188 /* If we stepped or ran into an internal breakpoint, we've
2189 already handled it. So next time we resume (from this
2190 PC), we should step over it. */
2192 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2194 if (breakpoint_here (event_child
->stop_pc
))
2195 event_child
->need_step_over
= 1;
2200 /* We have some other signal, possibly a step-over dance was in
2201 progress, and it should be cancelled too. */
2202 step_over_finished
= finish_step_over (event_child
);
2205 /* We have all the data we need. Either report the event to GDB, or
2206 resume threads and keep waiting for more. */
2208 /* If we're collecting a fast tracepoint, finish the collection and
2209 move out of the jump pad before delivering a signal. See
2210 linux_stabilize_threads. */
2213 && WSTOPSIG (w
) != SIGTRAP
2214 && supports_fast_tracepoints ()
2215 && in_process_agent_loaded ())
2219 "Got signal %d for LWP %ld. Check if we need "
2220 "to defer or adjust it.\n",
2221 WSTOPSIG (w
), lwpid_of (event_child
));
2223 /* Allow debugging the jump pad itself. */
2224 if (current_inferior
->last_resume_kind
!= resume_step
2225 && maybe_move_out_of_jump_pad (event_child
, &w
))
2227 enqueue_one_deferred_signal (event_child
, &w
);
2231 "Signal %d for LWP %ld deferred (in jump pad)\n",
2232 WSTOPSIG (w
), lwpid_of (event_child
));
2234 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2239 if (event_child
->collecting_fast_tracepoint
)
2243 LWP %ld was trying to move out of the jump pad (%d). \
2244 Check if we're already there.\n",
2245 lwpid_of (event_child
),
2246 event_child
->collecting_fast_tracepoint
);
2250 event_child
->collecting_fast_tracepoint
2251 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2253 if (event_child
->collecting_fast_tracepoint
!= 1)
2255 /* No longer need this breakpoint. */
2256 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2260 "No longer need exit-jump-pad bkpt; removing it."
2261 "stopping all threads momentarily.\n");
2263 /* Other running threads could hit this breakpoint.
2264 We don't handle moribund locations like GDB does,
2265 instead we always pause all threads when removing
2266 breakpoints, so that any step-over or
2267 decr_pc_after_break adjustment is always taken
2268 care of while the breakpoint is still
2270 stop_all_lwps (1, event_child
);
2271 cancel_breakpoints ();
2273 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2274 event_child
->exit_jump_pad_bkpt
= NULL
;
2276 unstop_all_lwps (1, event_child
);
2278 gdb_assert (event_child
->suspended
>= 0);
2282 if (event_child
->collecting_fast_tracepoint
== 0)
2286 "fast tracepoint finished "
2287 "collecting successfully.\n");
2289 /* We may have a deferred signal to report. */
2290 if (dequeue_one_deferred_signal (event_child
, &w
))
2293 fprintf (stderr
, "dequeued one signal.\n");
2298 fprintf (stderr
, "no deferred signals.\n");
2300 if (stabilizing_threads
)
2302 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2303 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2304 return ptid_of (event_child
);
2310 /* Check whether GDB would be interested in this event. */
2312 /* If GDB is not interested in this signal, don't stop other
2313 threads, and don't report it to GDB. Just resume the inferior
2314 right away. We do this for threading-related signals as well as
2315 any that GDB specifically requested we ignore. But never ignore
2316 SIGSTOP if we sent it ourselves, and do not ignore signals when
2317 stepping - they may require special handling to skip the signal
2319 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2322 && current_inferior
->last_resume_kind
!= resume_step
2324 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2325 (current_process ()->private->thread_db
!= NULL
2326 && (WSTOPSIG (w
) == __SIGRTMIN
2327 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2330 (pass_signals
[target_signal_from_host (WSTOPSIG (w
))]
2331 && !(WSTOPSIG (w
) == SIGSTOP
2332 && current_inferior
->last_resume_kind
== resume_stop
))))
2334 siginfo_t info
, *info_p
;
2337 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
2338 WSTOPSIG (w
), lwpid_of (event_child
));
2340 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
2344 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2345 WSTOPSIG (w
), info_p
);
2349 /* If GDB wanted this thread to single step, we always want to
2350 report the SIGTRAP, and let GDB handle it. Watchpoints should
2351 always be reported. So should signals we can't explain. A
2352 SIGTRAP we can't explain could be a GDB breakpoint --- we may or
2353 not support Z0 breakpoints. If we do, we're be able to handle
2354 GDB breakpoints on top of internal breakpoints, by handling the
2355 internal breakpoint and still reporting the event to GDB. If we
2356 don't, we're out of luck, GDB won't see the breakpoint hit. */
2357 report_to_gdb
= (!maybe_internal_trap
2358 || current_inferior
->last_resume_kind
== resume_step
2359 || event_child
->stopped_by_watchpoint
2360 || (!step_over_finished
2361 && !bp_explains_trap
&& !trace_event
)
2362 || gdb_breakpoint_here (event_child
->stop_pc
));
2364 /* We found no reason GDB would want us to stop. We either hit one
2365 of our own breakpoints, or finished an internal step GDB
2366 shouldn't know about. */
2371 if (bp_explains_trap
)
2372 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2373 if (step_over_finished
)
2374 fprintf (stderr
, "Step-over finished.\n");
2376 fprintf (stderr
, "Tracepoint event.\n");
2379 /* We're not reporting this breakpoint to GDB, so apply the
2380 decr_pc_after_break adjustment to the inferior's regcache
2383 if (the_low_target
.set_pc
!= NULL
)
2385 struct regcache
*regcache
2386 = get_thread_regcache (get_lwp_thread (event_child
), 1);
2387 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2390 /* We may have finished stepping over a breakpoint. If so,
2391 we've stopped and suspended all LWPs momentarily except the
2392 stepping one. This is where we resume them all again. We're
2393 going to keep waiting, so use proceed, which handles stepping
2394 over the next breakpoint. */
2396 fprintf (stderr
, "proceeding all threads.\n");
2398 if (step_over_finished
)
2399 unsuspend_all_lwps (event_child
);
2401 proceed_all_lwps ();
2407 if (current_inferior
->last_resume_kind
== resume_step
)
2408 fprintf (stderr
, "GDB wanted to single-step, reporting event.\n");
2409 if (event_child
->stopped_by_watchpoint
)
2410 fprintf (stderr
, "Stopped by watchpoint.\n");
2411 if (gdb_breakpoint_here (event_child
->stop_pc
))
2412 fprintf (stderr
, "Stopped by GDB breakpoint.\n");
2414 fprintf (stderr
, "Hit a non-gdbserver trap event.\n");
2417 /* Alright, we're going to report a stop. */
2419 if (!non_stop
&& !stabilizing_threads
)
2421 /* In all-stop, stop all threads. */
2422 stop_all_lwps (0, NULL
);
2424 /* If we're not waiting for a specific LWP, choose an event LWP
2425 from among those that have had events. Giving equal priority
2426 to all LWPs that have had events helps prevent
2428 if (ptid_equal (ptid
, minus_one_ptid
))
2430 event_child
->status_pending_p
= 1;
2431 event_child
->status_pending
= w
;
2433 select_event_lwp (&event_child
);
2435 event_child
->status_pending_p
= 0;
2436 w
= event_child
->status_pending
;
2439 /* Now that we've selected our final event LWP, cancel any
2440 breakpoints in other LWPs that have hit a GDB breakpoint.
2441 See the comment in cancel_breakpoints_callback to find out
2443 find_inferior (&all_lwps
, cancel_breakpoints_callback
, event_child
);
2445 /* Stabilize threads (move out of jump pads). */
2446 stabilize_threads ();
2450 /* If we just finished a step-over, then all threads had been
2451 momentarily paused. In all-stop, that's fine, we want
2452 threads stopped by now anyway. In non-stop, we need to
2453 re-resume threads that GDB wanted to be running. */
2454 if (step_over_finished
)
2455 unstop_all_lwps (1, event_child
);
2458 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2460 if (current_inferior
->last_resume_kind
== resume_stop
2461 && WSTOPSIG (w
) == SIGSTOP
)
2463 /* A thread that has been requested to stop by GDB with vCont;t,
2464 and it stopped cleanly, so report as SIG0. The use of
2465 SIGSTOP is an implementation detail. */
2466 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2468 else if (current_inferior
->last_resume_kind
== resume_stop
2469 && WSTOPSIG (w
) != SIGSTOP
)
2471 /* A thread that has been requested to stop by GDB with vCont;t,
2472 but, it stopped for other reasons. */
2473 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2477 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2480 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
2483 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
2484 target_pid_to_str (ptid_of (event_child
)),
2486 ourstatus
->value
.sig
);
2488 return ptid_of (event_child
);
2491 /* Get rid of any pending event in the pipe. */
2493 async_file_flush (void)
2499 ret
= read (linux_event_pipe
[0], &buf
, 1);
2500 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
2503 /* Put something in the pipe, so the event loop wakes up. */
2505 async_file_mark (void)
2509 async_file_flush ();
2512 ret
= write (linux_event_pipe
[1], "+", 1);
2513 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
2515 /* Ignore EAGAIN. If the pipe is full, the event loop will already
2516 be awakened anyway. */
2520 linux_wait (ptid_t ptid
,
2521 struct target_waitstatus
*ourstatus
, int target_options
)
2526 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
2528 /* Flush the async file first. */
2529 if (target_is_async_p ())
2530 async_file_flush ();
2532 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
2534 /* If at least one stop was reported, there may be more. A single
2535 SIGCHLD can signal more than one child stop. */
2536 if (target_is_async_p ()
2537 && (target_options
& TARGET_WNOHANG
) != 0
2538 && !ptid_equal (event_ptid
, null_ptid
))
2544 /* Send a signal to an LWP. */
2547 kill_lwp (unsigned long lwpid
, int signo
)
2549 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2550 fails, then we are not using nptl threads and we should be using kill. */
2554 static int tkill_failed
;
2561 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2562 if (errno
!= ENOSYS
)
2569 return kill (lwpid
, signo
);
2573 linux_stop_lwp (struct lwp_info
*lwp
)
2579 send_sigstop (struct lwp_info
*lwp
)
2583 pid
= lwpid_of (lwp
);
2585 /* If we already have a pending stop signal for this process, don't
2587 if (lwp
->stop_expected
)
2590 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
2596 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
2598 lwp
->stop_expected
= 1;
2599 kill_lwp (pid
, SIGSTOP
);
2603 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
2605 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2607 /* Ignore EXCEPT. */
2618 /* Increment the suspend count of an LWP, and stop it, if not stopped
2621 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
2624 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2626 /* Ignore EXCEPT. */
2632 return send_sigstop_callback (entry
, except
);
2636 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
2638 /* It's dead, really. */
2641 /* Store the exit status for later. */
2642 lwp
->status_pending_p
= 1;
2643 lwp
->status_pending
= wstat
;
2645 /* Prevent trying to stop it. */
2648 /* No further stops are expected from a dead lwp. */
2649 lwp
->stop_expected
= 0;
2653 wait_for_sigstop (struct inferior_list_entry
*entry
)
2655 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2656 struct thread_info
*saved_inferior
;
2665 fprintf (stderr
, "wait_for_sigstop: LWP %ld already stopped\n",
2670 saved_inferior
= current_inferior
;
2671 if (saved_inferior
!= NULL
)
2672 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
2674 saved_tid
= null_ptid
; /* avoid bogus unused warning */
2676 ptid
= lwp
->head
.id
;
2679 fprintf (stderr
, "wait_for_sigstop: pulling one event\n");
2681 pid
= linux_wait_for_event (ptid
, &wstat
, __WALL
);
2683 /* If we stopped with a non-SIGSTOP signal, save it for later
2684 and record the pending SIGSTOP. If the process exited, just
2686 if (WIFSTOPPED (wstat
))
2689 fprintf (stderr
, "LWP %ld stopped with signal %d\n",
2690 lwpid_of (lwp
), WSTOPSIG (wstat
));
2692 if (WSTOPSIG (wstat
) != SIGSTOP
)
2695 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
2696 lwpid_of (lwp
), wstat
);
2698 lwp
->status_pending_p
= 1;
2699 lwp
->status_pending
= wstat
;
2705 fprintf (stderr
, "Process %d exited while stopping LWPs\n", pid
);
2707 lwp
= find_lwp_pid (pid_to_ptid (pid
));
2710 /* Leave this status pending for the next time we're able to
2711 report it. In the mean time, we'll report this lwp as
2712 dead to GDB, so GDB doesn't try to read registers and
2713 memory from it. This can only happen if this was the
2714 last thread of the process; otherwise, PID is removed
2715 from the thread tables before linux_wait_for_event
2717 mark_lwp_dead (lwp
, wstat
);
2721 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
2722 current_inferior
= saved_inferior
;
2726 fprintf (stderr
, "Previously current thread died.\n");
2730 /* We can't change the current inferior behind GDB's back,
2731 otherwise, a subsequent command may apply to the wrong
2733 current_inferior
= NULL
;
2737 /* Set a valid thread as current. */
2738 set_desired_inferior (0);
2743 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
2744 move it out, because we need to report the stop event to GDB. For
2745 example, if the user puts a breakpoint in the jump pad, it's
2746 because she wants to debug it. */
2749 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
2751 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2752 struct thread_info
*thread
= get_lwp_thread (lwp
);
2754 gdb_assert (lwp
->suspended
== 0);
2755 gdb_assert (lwp
->stopped
);
2757 /* Allow debugging the jump pad, gdb_collect, etc.. */
2758 return (supports_fast_tracepoints ()
2759 && in_process_agent_loaded ()
2760 && (gdb_breakpoint_here (lwp
->stop_pc
)
2761 || lwp
->stopped_by_watchpoint
2762 || thread
->last_resume_kind
== resume_step
)
2763 && linux_fast_tracepoint_collecting (lwp
, NULL
));
2767 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
2769 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2770 struct thread_info
*thread
= get_lwp_thread (lwp
);
2773 gdb_assert (lwp
->suspended
== 0);
2774 gdb_assert (lwp
->stopped
);
2776 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
2778 /* Allow debugging the jump pad, gdb_collect, etc. */
2779 if (!gdb_breakpoint_here (lwp
->stop_pc
)
2780 && !lwp
->stopped_by_watchpoint
2781 && thread
->last_resume_kind
!= resume_step
2782 && maybe_move_out_of_jump_pad (lwp
, wstat
))
2786 "LWP %ld needs stabilizing (in jump pad)\n",
2791 lwp
->status_pending_p
= 0;
2792 enqueue_one_deferred_signal (lwp
, wstat
);
2796 "Signal %d for LWP %ld deferred "
2798 WSTOPSIG (*wstat
), lwpid_of (lwp
));
2801 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
2808 lwp_running (struct inferior_list_entry
*entry
, void *data
)
2810 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2819 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
2820 If SUSPEND, then also increase the suspend count of every LWP,
2824 stop_all_lwps (int suspend
, struct lwp_info
*except
)
2826 stopping_threads
= 1;
2829 find_inferior (&all_lwps
, suspend_and_send_sigstop_callback
, except
);
2831 find_inferior (&all_lwps
, send_sigstop_callback
, except
);
2832 for_each_inferior (&all_lwps
, wait_for_sigstop
);
2833 stopping_threads
= 0;
2836 /* Resume execution of the inferior process.
2837 If STEP is nonzero, single-step it.
2838 If SIGNAL is nonzero, give it that signal. */
2841 linux_resume_one_lwp (struct lwp_info
*lwp
,
2842 int step
, int signal
, siginfo_t
*info
)
2844 struct thread_info
*saved_inferior
;
2845 int fast_tp_collecting
;
2847 if (lwp
->stopped
== 0)
2850 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
2852 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
2854 /* Cancel actions that rely on GDB not changing the PC (e.g., the
2855 user used the "jump" command, or "set $pc = foo"). */
2856 if (lwp
->stop_pc
!= get_pc (lwp
))
2858 /* Collecting 'while-stepping' actions doesn't make sense
2860 release_while_stepping_state_list (get_lwp_thread (lwp
));
2863 /* If we have pending signals or status, and a new signal, enqueue the
2864 signal. Also enqueue the signal if we are waiting to reinsert a
2865 breakpoint; it will be picked up again below. */
2867 && (lwp
->status_pending_p
2868 || lwp
->pending_signals
!= NULL
2869 || lwp
->bp_reinsert
!= 0
2870 || fast_tp_collecting
))
2872 struct pending_signals
*p_sig
;
2873 p_sig
= xmalloc (sizeof (*p_sig
));
2874 p_sig
->prev
= lwp
->pending_signals
;
2875 p_sig
->signal
= signal
;
2877 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
2879 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
2880 lwp
->pending_signals
= p_sig
;
2883 if (lwp
->status_pending_p
)
2886 fprintf (stderr
, "Not resuming lwp %ld (%s, signal %d, stop %s);"
2887 " has pending status\n",
2888 lwpid_of (lwp
), step
? "step" : "continue", signal
,
2889 lwp
->stop_expected
? "expected" : "not expected");
2893 saved_inferior
= current_inferior
;
2894 current_inferior
= get_lwp_thread (lwp
);
2897 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
2898 lwpid_of (lwp
), step
? "step" : "continue", signal
,
2899 lwp
->stop_expected
? "expected" : "not expected");
2901 /* This bit needs some thinking about. If we get a signal that
2902 we must report while a single-step reinsert is still pending,
2903 we often end up resuming the thread. It might be better to
2904 (ew) allow a stack of pending events; then we could be sure that
2905 the reinsert happened right away and not lose any signals.
2907 Making this stack would also shrink the window in which breakpoints are
2908 uninserted (see comment in linux_wait_for_lwp) but not enough for
2909 complete correctness, so it won't solve that problem. It may be
2910 worthwhile just to solve this one, however. */
2911 if (lwp
->bp_reinsert
!= 0)
2914 fprintf (stderr
, " pending reinsert at 0x%s\n",
2915 paddress (lwp
->bp_reinsert
));
2917 if (lwp
->bp_reinsert
!= 0 && can_hardware_single_step ())
2919 if (fast_tp_collecting
== 0)
2922 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
2924 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
2931 /* Postpone any pending signal. It was enqueued above. */
2935 if (fast_tp_collecting
== 1)
2939 lwp %ld wants to get out of fast tracepoint jump pad (exit-jump-pad-bkpt)\n",
2942 /* Postpone any pending signal. It was enqueued above. */
2945 else if (fast_tp_collecting
== 2)
2949 lwp %ld wants to get out of fast tracepoint jump pad single-stepping\n",
2952 if (can_hardware_single_step ())
2955 fatal ("moving out of jump pad single-stepping"
2956 " not implemented on this target");
2958 /* Postpone any pending signal. It was enqueued above. */
2962 /* If we have while-stepping actions in this thread set it stepping.
2963 If we have a signal to deliver, it may or may not be set to
2964 SIG_IGN, we don't know. Assume so, and allow collecting
2965 while-stepping into a signal handler. A possible smart thing to
2966 do would be to set an internal breakpoint at the signal return
2967 address, continue, and carry on catching this while-stepping
2968 action only when that breakpoint is hit. A future
2970 if (get_lwp_thread (lwp
)->while_stepping
!= NULL
2971 && can_hardware_single_step ())
2975 "lwp %ld has a while-stepping action -> forcing step.\n",
2980 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
2982 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
2983 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
2984 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
2987 /* If we have pending signals, consume one unless we are trying to
2988 reinsert a breakpoint or we're trying to finish a fast tracepoint
2990 if (lwp
->pending_signals
!= NULL
2991 && lwp
->bp_reinsert
== 0
2992 && fast_tp_collecting
== 0)
2994 struct pending_signals
**p_sig
;
2996 p_sig
= &lwp
->pending_signals
;
2997 while ((*p_sig
)->prev
!= NULL
)
2998 p_sig
= &(*p_sig
)->prev
;
3000 signal
= (*p_sig
)->signal
;
3001 if ((*p_sig
)->info
.si_signo
!= 0)
3002 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
3008 if (the_low_target
.prepare_to_resume
!= NULL
)
3009 the_low_target
.prepare_to_resume (lwp
);
3011 regcache_invalidate_one ((struct inferior_list_entry
*)
3012 get_lwp_thread (lwp
));
3015 lwp
->stopped_by_watchpoint
= 0;
3016 lwp
->stepping
= step
;
3017 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0,
3018 /* Coerce to a uintptr_t first to avoid potential gcc warning
3019 of coercing an 8 byte integer to a 4 byte pointer. */
3020 (PTRACE_ARG4_TYPE
) (uintptr_t) signal
);
3022 current_inferior
= saved_inferior
;
3025 /* ESRCH from ptrace either means that the thread was already
3026 running (an error) or that it is gone (a race condition). If
3027 it's gone, we will get a notification the next time we wait,
3028 so we can ignore the error. We could differentiate these
3029 two, but it's tricky without waiting; the thread still exists
3030 as a zombie, so sending it signal 0 would succeed. So just
3035 perror_with_name ("ptrace");
3039 struct thread_resume_array
3041 struct thread_resume
*resume
;
3045 /* This function is called once per thread. We look up the thread
3046 in RESUME_PTR, and mark the thread with a pointer to the appropriate
3049 This algorithm is O(threads * resume elements), but resume elements
3050 is small (and will remain small at least until GDB supports thread
3053 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3055 struct lwp_info
*lwp
;
3056 struct thread_info
*thread
;
3058 struct thread_resume_array
*r
;
3060 thread
= (struct thread_info
*) entry
;
3061 lwp
= get_thread_lwp (thread
);
3064 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3066 ptid_t ptid
= r
->resume
[ndx
].thread
;
3067 if (ptid_equal (ptid
, minus_one_ptid
)
3068 || ptid_equal (ptid
, entry
->id
)
3069 || (ptid_is_pid (ptid
)
3070 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
3071 || (ptid_get_lwp (ptid
) == -1
3072 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
3074 if (r
->resume
[ndx
].kind
== resume_stop
3075 && thread
->last_resume_kind
== resume_stop
)
3078 fprintf (stderr
, "already %s LWP %ld at GDB's request\n",
3079 thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
3087 lwp
->resume
= &r
->resume
[ndx
];
3088 thread
->last_resume_kind
= lwp
->resume
->kind
;
3090 /* If we had a deferred signal to report, dequeue one now.
3091 This can happen if LWP gets more than one signal while
3092 trying to get out of a jump pad. */
3094 && !lwp
->status_pending_p
3095 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3097 lwp
->status_pending_p
= 1;
3101 "Dequeueing deferred signal %d for LWP %ld, "
3102 "leaving status pending.\n",
3103 WSTOPSIG (lwp
->status_pending
), lwpid_of (lwp
));
3110 /* No resume action for this thread. */
3117 /* Set *FLAG_P if this lwp has an interesting status pending. */
3119 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3121 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3123 /* LWPs which will not be resumed are not interesting, because
3124 we might not wait for them next time through linux_wait. */
3125 if (lwp
->resume
== NULL
)
3128 if (lwp
->status_pending_p
)
3129 * (int *) flag_p
= 1;
3134 /* Return 1 if this lwp that GDB wants running is stopped at an
3135 internal breakpoint that we need to step over. It assumes that any
3136 required STOP_PC adjustment has already been propagated to the
3137 inferior's regcache. */
3140 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3142 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3143 struct thread_info
*thread
;
3144 struct thread_info
*saved_inferior
;
3147 /* LWPs which will not be resumed are not interesting, because we
3148 might not wait for them next time through linux_wait. */
3154 "Need step over [LWP %ld]? Ignoring, not stopped\n",
3159 thread
= get_lwp_thread (lwp
);
3161 if (thread
->last_resume_kind
== resume_stop
)
3165 "Need step over [LWP %ld]? Ignoring, should remain stopped\n",
3170 gdb_assert (lwp
->suspended
>= 0);
3176 "Need step over [LWP %ld]? Ignoring, suspended\n",
3181 if (!lwp
->need_step_over
)
3185 "Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
3188 if (lwp
->status_pending_p
)
3192 "Need step over [LWP %ld]? Ignoring, has pending status.\n",
3197 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3201 /* If the PC has changed since we stopped, then don't do anything,
3202 and let the breakpoint/tracepoint be hit. This happens if, for
3203 instance, GDB handled the decr_pc_after_break subtraction itself,
3204 GDB is OOL stepping this thread, or the user has issued a "jump"
3205 command, or poked thread's registers herself. */
3206 if (pc
!= lwp
->stop_pc
)
3210 "Need step over [LWP %ld]? Cancelling, PC was changed. "
3211 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3212 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
3214 lwp
->need_step_over
= 0;
3218 saved_inferior
= current_inferior
;
3219 current_inferior
= thread
;
3221 /* We can only step over breakpoints we know about. */
3222 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3224 /* Don't step over a breakpoint that GDB expects to hit
3226 if (gdb_breakpoint_here (pc
))
3230 "Need step over [LWP %ld]? yes, but found"
3231 " GDB breakpoint at 0x%s; skipping step over\n",
3232 lwpid_of (lwp
), paddress (pc
));
3234 current_inferior
= saved_inferior
;
3241 "Need step over [LWP %ld]? yes, "
3242 "found breakpoint at 0x%s\n",
3243 lwpid_of (lwp
), paddress (pc
));
3245 /* We've found an lwp that needs stepping over --- return 1 so
3246 that find_inferior stops looking. */
3247 current_inferior
= saved_inferior
;
3249 /* If the step over is cancelled, this is set again. */
3250 lwp
->need_step_over
= 0;
3255 current_inferior
= saved_inferior
;
3259 "Need step over [LWP %ld]? No, no breakpoint found at 0x%s\n",
3260 lwpid_of (lwp
), paddress (pc
));
3265 /* Start a step-over operation on LWP. When LWP stopped at a
3266 breakpoint, to make progress, we need to remove the breakpoint out
3267 of the way. If we let other threads run while we do that, they may
3268 pass by the breakpoint location and miss hitting it. To avoid
3269 that, a step-over momentarily stops all threads while LWP is
3270 single-stepped while the breakpoint is temporarily uninserted from
3271 the inferior. When the single-step finishes, we reinsert the
3272 breakpoint, and let all threads that are supposed to be running,
3275 On targets that don't support hardware single-step, we don't
3276 currently support full software single-stepping. Instead, we only
3277 support stepping over the thread event breakpoint, by asking the
3278 low target where to place a reinsert breakpoint. Since this
3279 routine assumes the breakpoint being stepped over is a thread event
3280 breakpoint, it usually assumes the return address of the current
3281 function is a good enough place to set the reinsert breakpoint. */
3284 start_step_over (struct lwp_info
*lwp
)
3286 struct thread_info
*saved_inferior
;
3292 "Starting step-over on LWP %ld. Stopping all threads\n",
3295 stop_all_lwps (1, lwp
);
3296 gdb_assert (lwp
->suspended
== 0);
3299 fprintf (stderr
, "Done stopping all threads for step-over.\n");
3301 /* Note, we should always reach here with an already adjusted PC,
3302 either by GDB (if we're resuming due to GDB's request), or by our
3303 caller, if we just finished handling an internal breakpoint GDB
3304 shouldn't care about. */
3307 saved_inferior
= current_inferior
;
3308 current_inferior
= get_lwp_thread (lwp
);
3310 lwp
->bp_reinsert
= pc
;
3311 uninsert_breakpoints_at (pc
);
3312 uninsert_fast_tracepoint_jumps_at (pc
);
3314 if (can_hardware_single_step ())
3320 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3321 set_reinsert_breakpoint (raddr
);
3325 current_inferior
= saved_inferior
;
3327 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3329 /* Require next event from this LWP. */
3330 step_over_bkpt
= lwp
->head
.id
;
3334 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3335 start_step_over, if still there, and delete any reinsert
3336 breakpoints we've set, on non hardware single-step targets. */
3339 finish_step_over (struct lwp_info
*lwp
)
3341 if (lwp
->bp_reinsert
!= 0)
3344 fprintf (stderr
, "Finished step over.\n");
3346 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3347 may be no breakpoint to reinsert there by now. */
3348 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3349 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3351 lwp
->bp_reinsert
= 0;
3353 /* Delete any software-single-step reinsert breakpoints. No
3354 longer needed. We don't have to worry about other threads
3355 hitting this trap, and later not being able to explain it,
3356 because we were stepping over a breakpoint, and we hold all
3357 threads but LWP stopped while doing that. */
3358 if (!can_hardware_single_step ())
3359 delete_reinsert_breakpoints ();
3361 step_over_bkpt
= null_ptid
;
3368 /* This function is called once per thread. We check the thread's resume
3369 request, which will tell us whether to resume, step, or leave the thread
3370 stopped; and what signal, if any, it should be sent.
3372 For threads which we aren't explicitly told otherwise, we preserve
3373 the stepping flag; this is used for stepping over gdbserver-placed
3376 If pending_flags was set in any thread, we queue any needed
3377 signals, since we won't actually resume. We already have a pending
3378 event to report, so we don't need to preserve any step requests;
3379 they should be re-issued if necessary. */
3382 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3384 struct lwp_info
*lwp
;
3385 struct thread_info
*thread
;
3387 int leave_all_stopped
= * (int *) arg
;
3390 thread
= (struct thread_info
*) entry
;
3391 lwp
= get_thread_lwp (thread
);
3393 if (lwp
->resume
== NULL
)
3396 if (lwp
->resume
->kind
== resume_stop
)
3399 fprintf (stderr
, "resume_stop request for LWP %ld\n", lwpid_of (lwp
));
3404 fprintf (stderr
, "stopping LWP %ld\n", lwpid_of (lwp
));
3406 /* Stop the thread, and wait for the event asynchronously,
3407 through the event loop. */
3413 fprintf (stderr
, "already stopped LWP %ld\n",
3416 /* The LWP may have been stopped in an internal event that
3417 was not meant to be notified back to GDB (e.g., gdbserver
3418 breakpoint), so we should be reporting a stop event in
3421 /* If the thread already has a pending SIGSTOP, this is a
3422 no-op. Otherwise, something later will presumably resume
3423 the thread and this will cause it to cancel any pending
3424 operation, due to last_resume_kind == resume_stop. If
3425 the thread already has a pending status to report, we
3426 will still report it the next time we wait - see
3427 status_pending_p_callback. */
3429 /* If we already have a pending signal to report, then
3430 there's no need to queue a SIGSTOP, as this means we're
3431 midway through moving the LWP out of the jumppad, and we
3432 will report the pending signal as soon as that is
3434 if (lwp
->pending_signals_to_report
== NULL
)
3438 /* For stop requests, we're done. */
3440 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3444 /* If this thread which is about to be resumed has a pending status,
3445 then don't resume any threads - we can just report the pending
3446 status. Make sure to queue any signals that would otherwise be
3447 sent. In all-stop mode, we do this decision based on if *any*
3448 thread has a pending status. If there's a thread that needs the
3449 step-over-breakpoint dance, then don't resume any other thread
3450 but that particular one. */
3451 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
3456 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
3458 step
= (lwp
->resume
->kind
== resume_step
);
3459 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
3464 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
3466 /* If we have a new signal, enqueue the signal. */
3467 if (lwp
->resume
->sig
!= 0)
3469 struct pending_signals
*p_sig
;
3470 p_sig
= xmalloc (sizeof (*p_sig
));
3471 p_sig
->prev
= lwp
->pending_signals
;
3472 p_sig
->signal
= lwp
->resume
->sig
;
3473 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3475 /* If this is the same signal we were previously stopped by,
3476 make sure to queue its siginfo. We can ignore the return
3477 value of ptrace; if it fails, we'll skip
3478 PTRACE_SETSIGINFO. */
3479 if (WIFSTOPPED (lwp
->last_status
)
3480 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
3481 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
3483 lwp
->pending_signals
= p_sig
;
3487 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3493 linux_resume (struct thread_resume
*resume_info
, size_t n
)
3495 struct thread_resume_array array
= { resume_info
, n
};
3496 struct lwp_info
*need_step_over
= NULL
;
3498 int leave_all_stopped
;
3500 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
3502 /* If there is a thread which would otherwise be resumed, which has
3503 a pending status, then don't resume any threads - we can just
3504 report the pending status. Make sure to queue any signals that
3505 would otherwise be sent. In non-stop mode, we'll apply this
3506 logic to each thread individually. We consume all pending events
3507 before considering to start a step-over (in all-stop). */
3510 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
3512 /* If there is a thread which would otherwise be resumed, which is
3513 stopped at a breakpoint that needs stepping over, then don't
3514 resume any threads - have it step over the breakpoint with all
3515 other threads stopped, then resume all threads again. Make sure
3516 to queue any signals that would otherwise be delivered or
3518 if (!any_pending
&& supports_breakpoints ())
3520 = (struct lwp_info
*) find_inferior (&all_lwps
,
3521 need_step_over_p
, NULL
);
3523 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
3527 if (need_step_over
!= NULL
)
3528 fprintf (stderr
, "Not resuming all, need step over\n");
3529 else if (any_pending
)
3531 "Not resuming, all-stop and found "
3532 "an LWP with pending status\n");
3534 fprintf (stderr
, "Resuming, no pending status or step over needed\n");
3537 /* Even if we're leaving threads stopped, queue all signals we'd
3538 otherwise deliver. */
3539 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
3542 start_step_over (need_step_over
);
3545 /* This function is called once per thread. We check the thread's
3546 last resume request, which will tell us whether to resume, step, or
3547 leave the thread stopped. Any signal the client requested to be
3548 delivered has already been enqueued at this point.
3550 If any thread that GDB wants running is stopped at an internal
3551 breakpoint that needs stepping over, we start a step-over operation
3552 on that particular thread, and leave all others stopped. */
3555 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3557 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3558 struct thread_info
*thread
;
3566 "proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
3571 fprintf (stderr
, " LWP %ld already running\n", lwpid_of (lwp
));
3575 thread
= get_lwp_thread (lwp
);
3577 if (thread
->last_resume_kind
== resume_stop
3578 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
3581 fprintf (stderr
, " client wants LWP to remain %ld stopped\n",
3586 if (lwp
->status_pending_p
)
3589 fprintf (stderr
, " LWP %ld has pending status, leaving stopped\n",
3594 gdb_assert (lwp
->suspended
>= 0);
3599 fprintf (stderr
, " LWP %ld is suspended\n", lwpid_of (lwp
));
3603 if (thread
->last_resume_kind
== resume_stop
3604 && lwp
->pending_signals_to_report
== NULL
3605 && lwp
->collecting_fast_tracepoint
== 0)
3607 /* We haven't reported this LWP as stopped yet (otherwise, the
3608 last_status.kind check above would catch it, and we wouldn't
3609 reach here. This LWP may have been momentarily paused by a
3610 stop_all_lwps call while handling for example, another LWP's
3611 step-over. In that case, the pending expected SIGSTOP signal
3612 that was queued at vCont;t handling time will have already
3613 been consumed by wait_for_sigstop, and so we need to requeue
3614 another one here. Note that if the LWP already has a SIGSTOP
3615 pending, this is a no-op. */
3619 "Client wants LWP %ld to stop. "
3620 "Making sure it has a SIGSTOP pending\n",
3626 step
= thread
->last_resume_kind
== resume_step
;
3627 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3632 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3634 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3640 gdb_assert (lwp
->suspended
>= 0);
3642 return proceed_one_lwp (entry
, except
);
3645 /* When we finish a step-over, set threads running again. If there's
3646 another thread that may need a step-over, now's the time to start
3647 it. Eventually, we'll move all threads past their breakpoints. */
3650 proceed_all_lwps (void)
3652 struct lwp_info
*need_step_over
;
3654 /* If there is a thread which would otherwise be resumed, which is
3655 stopped at a breakpoint that needs stepping over, then don't
3656 resume any threads - have it step over the breakpoint with all
3657 other threads stopped, then resume all threads again. */
3659 if (supports_breakpoints ())
3662 = (struct lwp_info
*) find_inferior (&all_lwps
,
3663 need_step_over_p
, NULL
);
3665 if (need_step_over
!= NULL
)
3668 fprintf (stderr
, "proceed_all_lwps: found "
3669 "thread %ld needing a step-over\n",
3670 lwpid_of (need_step_over
));
3672 start_step_over (need_step_over
);
3678 fprintf (stderr
, "Proceeding, no step-over needed\n");
3680 find_inferior (&all_lwps
, proceed_one_lwp
, NULL
);
3683 /* Stopped LWPs that the client wanted to be running, that don't have
3684 pending statuses, are set to run again, except for EXCEPT, if not
3685 NULL. This undoes a stop_all_lwps call. */
3688 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
3694 "unstopping all lwps, except=(LWP %ld)\n", lwpid_of (except
));
3697 "unstopping all lwps\n");
3701 find_inferior (&all_lwps
, unsuspend_and_proceed_one_lwp
, except
);
3703 find_inferior (&all_lwps
, proceed_one_lwp
, except
);
3706 #ifdef HAVE_LINUX_USRREGS
3709 register_addr (int regnum
)
3713 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
3714 error ("Invalid register number %d.", regnum
);
3716 addr
= the_low_target
.regmap
[regnum
];
3721 /* Fetch one register. */
3723 fetch_register (struct regcache
*regcache
, int regno
)
3730 if (regno
>= the_low_target
.num_regs
)
3732 if ((*the_low_target
.cannot_fetch_register
) (regno
))
3735 regaddr
= register_addr (regno
);
3739 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
3740 & -sizeof (PTRACE_XFER_TYPE
));
3741 buf
= alloca (size
);
3743 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3744 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
3747 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
3748 ptrace (PTRACE_PEEKUSER
, pid
,
3749 /* Coerce to a uintptr_t first to avoid potential gcc warning
3750 of coercing an 8 byte integer to a 4 byte pointer. */
3751 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
, 0);
3752 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
3754 error ("reading register %d: %s", regno
, strerror (errno
));
3757 if (the_low_target
.supply_ptrace_register
)
3758 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
3760 supply_register (regcache
, regno
, buf
);
3763 /* Store one register. */
3765 store_register (struct regcache
*regcache
, int regno
)
3772 if (regno
>= the_low_target
.num_regs
)
3774 if ((*the_low_target
.cannot_store_register
) (regno
))
3777 regaddr
= register_addr (regno
);
3781 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
3782 & -sizeof (PTRACE_XFER_TYPE
));
3783 buf
= alloca (size
);
3784 memset (buf
, 0, size
);
3786 if (the_low_target
.collect_ptrace_register
)
3787 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
3789 collect_register (regcache
, regno
, buf
);
3791 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3792 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
3795 ptrace (PTRACE_POKEUSER
, pid
,
3796 /* Coerce to a uintptr_t first to avoid potential gcc warning
3797 about coercing an 8 byte integer to a 4 byte pointer. */
3798 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
,
3799 (PTRACE_ARG4_TYPE
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
3802 /* At this point, ESRCH should mean the process is
3803 already gone, in which case we simply ignore attempts
3804 to change its registers. See also the related
3805 comment in linux_resume_one_lwp. */
3809 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
3810 error ("writing register %d: %s", regno
, strerror (errno
));
3812 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
3816 /* Fetch all registers, or just one, from the child process. */
3818 usr_fetch_inferior_registers (struct regcache
*regcache
, int regno
)
3821 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
3822 fetch_register (regcache
, regno
);
3824 fetch_register (regcache
, regno
);
3827 /* Store our register values back into the inferior.
3828 If REGNO is -1, do this for all registers.
3829 Otherwise, REGNO specifies which register (so we can save time). */
3831 usr_store_inferior_registers (struct regcache
*regcache
, int regno
)
3834 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
3835 store_register (regcache
, regno
);
3837 store_register (regcache
, regno
);
3839 #endif /* HAVE_LINUX_USRREGS */
3843 #ifdef HAVE_LINUX_REGSETS
3846 regsets_fetch_inferior_registers (struct regcache
*regcache
)
3848 struct regset_info
*regset
;
3849 int saw_general_regs
= 0;
3853 regset
= target_regsets
;
3855 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3856 while (regset
->size
>= 0)
3861 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
3867 buf
= xmalloc (regset
->size
);
3869 nt_type
= regset
->nt_type
;
3873 iov
.iov_len
= regset
->size
;
3874 data
= (void *) &iov
;
3880 res
= ptrace (regset
->get_request
, pid
, nt_type
, data
);
3882 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
3888 /* If we get EIO on a regset, do not try it again for
3890 disabled_regsets
[regset
- target_regsets
] = 1;
3897 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
3902 else if (regset
->type
== GENERAL_REGS
)
3903 saw_general_regs
= 1;
3904 regset
->store_function (regcache
, buf
);
3908 if (saw_general_regs
)
3915 regsets_store_inferior_registers (struct regcache
*regcache
)
3917 struct regset_info
*regset
;
3918 int saw_general_regs
= 0;
3922 regset
= target_regsets
;
3924 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3925 while (regset
->size
>= 0)
3930 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
3936 buf
= xmalloc (regset
->size
);
3938 /* First fill the buffer with the current register set contents,
3939 in case there are any items in the kernel's regset that are
3940 not in gdbserver's regcache. */
3942 nt_type
= regset
->nt_type
;
3946 iov
.iov_len
= regset
->size
;
3947 data
= (void *) &iov
;
3953 res
= ptrace (regset
->get_request
, pid
, nt_type
, data
);
3955 res
= ptrace (regset
->get_request
, pid
, &iov
, data
);
3960 /* Then overlay our cached registers on that. */
3961 regset
->fill_function (regcache
, buf
);
3963 /* Only now do we write the register set. */
3965 res
= ptrace (regset
->set_request
, pid
, nt_type
, data
);
3967 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
3975 /* If we get EIO on a regset, do not try it again for
3977 disabled_regsets
[regset
- target_regsets
] = 1;
3981 else if (errno
== ESRCH
)
3983 /* At this point, ESRCH should mean the process is
3984 already gone, in which case we simply ignore attempts
3985 to change its registers. See also the related
3986 comment in linux_resume_one_lwp. */
3992 perror ("Warning: ptrace(regsets_store_inferior_registers)");
3995 else if (regset
->type
== GENERAL_REGS
)
3996 saw_general_regs
= 1;
4000 if (saw_general_regs
)
4007 #endif /* HAVE_LINUX_REGSETS */
4011 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4013 #ifdef HAVE_LINUX_REGSETS
4014 if (regsets_fetch_inferior_registers (regcache
) == 0)
4017 #ifdef HAVE_LINUX_USRREGS
4018 usr_fetch_inferior_registers (regcache
, regno
);
4023 linux_store_registers (struct regcache
*regcache
, int regno
)
4025 #ifdef HAVE_LINUX_REGSETS
4026 if (regsets_store_inferior_registers (regcache
) == 0)
4029 #ifdef HAVE_LINUX_USRREGS
4030 usr_store_inferior_registers (regcache
, regno
);
4035 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4036 to debugger memory starting at MYADDR. */
4039 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4042 /* Round starting address down to longword boundary. */
4043 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4044 /* Round ending address up; get number of longwords that makes. */
4046 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4047 / sizeof (PTRACE_XFER_TYPE
);
4048 /* Allocate buffer of that many longwords. */
4049 register PTRACE_XFER_TYPE
*buffer
4050 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4053 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4055 /* Try using /proc. Don't bother for one word. */
4056 if (len
>= 3 * sizeof (long))
4058 /* We could keep this file open and cache it - possibly one per
4059 thread. That requires some juggling, but is even faster. */
4060 sprintf (filename
, "/proc/%d/mem", pid
);
4061 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4065 /* If pread64 is available, use it. It's faster if the kernel
4066 supports it (only one syscall), and it's 64-bit safe even on
4067 32-bit platforms (for instance, SPARC debugging a SPARC64
4070 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
4072 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, myaddr
, len
) != len
)
4084 /* Read all the longwords */
4085 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4088 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4089 about coercing an 8 byte integer to a 4 byte pointer. */
4090 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4091 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4096 /* Copy appropriate bytes out of the buffer. */
4098 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4104 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4105 memory at MEMADDR. On failure (cannot write to the inferior)
4106 returns the value of errno. */
4109 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4112 /* Round starting address down to longword boundary. */
4113 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4114 /* Round ending address up; get number of longwords that makes. */
4116 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4117 / sizeof (PTRACE_XFER_TYPE
);
4119 /* Allocate buffer of that many longwords. */
4120 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4121 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4123 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4127 /* Dump up to four bytes. */
4128 unsigned int val
= * (unsigned int *) myaddr
;
4134 val
= val
& 0xffffff;
4135 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4136 val
, (long)memaddr
);
4139 /* Fill start and end extra bytes of buffer with existing memory data. */
4142 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4143 about coercing an 8 byte integer to a 4 byte pointer. */
4144 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4145 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4153 = ptrace (PTRACE_PEEKTEXT
, pid
,
4154 /* Coerce to a uintptr_t first to avoid potential gcc warning
4155 about coercing an 8 byte integer to a 4 byte pointer. */
4156 (PTRACE_ARG3_TYPE
) (uintptr_t) (addr
+ (count
- 1)
4157 * sizeof (PTRACE_XFER_TYPE
)),
4163 /* Copy data to be written over corresponding part of buffer. */
4165 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4168 /* Write the entire buffer. */
4170 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4173 ptrace (PTRACE_POKETEXT
, pid
,
4174 /* Coerce to a uintptr_t first to avoid potential gcc warning
4175 about coercing an 8 byte integer to a 4 byte pointer. */
4176 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
4177 (PTRACE_ARG4_TYPE
) buffer
[i
]);
4185 /* Non-zero if the kernel supports PTRACE_O_TRACEFORK. */
4186 static int linux_supports_tracefork_flag
;
4189 linux_enable_event_reporting (int pid
)
4191 if (!linux_supports_tracefork_flag
)
4194 ptrace (PTRACE_SETOPTIONS
, pid
, 0, (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
4197 /* Helper functions for linux_test_for_tracefork, called via clone (). */
4200 linux_tracefork_grandchild (void *arg
)
4205 #define STACK_SIZE 4096
4208 linux_tracefork_child (void *arg
)
4210 ptrace (PTRACE_TRACEME
, 0, 0, 0);
4211 kill (getpid (), SIGSTOP
);
4213 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4216 linux_tracefork_grandchild (NULL
);
4218 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4221 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
4222 CLONE_VM
| SIGCHLD
, NULL
);
4224 clone (linux_tracefork_grandchild
, (char *) arg
+ STACK_SIZE
,
4225 CLONE_VM
| SIGCHLD
, NULL
);
4228 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4233 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
4234 sure that we can enable the option, and that it had the desired
4238 linux_test_for_tracefork (void)
4240 int child_pid
, ret
, status
;
4242 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4243 char *stack
= xmalloc (STACK_SIZE
* 4);
4244 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4246 linux_supports_tracefork_flag
= 0;
4248 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4250 child_pid
= fork ();
4252 linux_tracefork_child (NULL
);
4254 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4256 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
4258 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
4259 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4260 #else /* !__ia64__ */
4261 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
4262 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4263 #endif /* !__ia64__ */
4265 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4267 if (child_pid
== -1)
4268 perror_with_name ("clone");
4270 ret
= my_waitpid (child_pid
, &status
, 0);
4272 perror_with_name ("waitpid");
4273 else if (ret
!= child_pid
)
4274 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
4275 if (! WIFSTOPPED (status
))
4276 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
4278 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
4279 (PTRACE_ARG4_TYPE
) PTRACE_O_TRACEFORK
);
4282 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4285 warning ("linux_test_for_tracefork: failed to kill child");
4289 ret
= my_waitpid (child_pid
, &status
, 0);
4290 if (ret
!= child_pid
)
4291 warning ("linux_test_for_tracefork: failed to wait for killed child");
4292 else if (!WIFSIGNALED (status
))
4293 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
4294 "killed child", status
);
4299 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
4301 warning ("linux_test_for_tracefork: failed to resume child");
4303 ret
= my_waitpid (child_pid
, &status
, 0);
4305 if (ret
== child_pid
&& WIFSTOPPED (status
)
4306 && status
>> 16 == PTRACE_EVENT_FORK
)
4309 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
4310 if (ret
== 0 && second_pid
!= 0)
4314 linux_supports_tracefork_flag
= 1;
4315 my_waitpid (second_pid
, &second_status
, 0);
4316 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
4318 warning ("linux_test_for_tracefork: failed to kill second child");
4319 my_waitpid (second_pid
, &status
, 0);
4323 warning ("linux_test_for_tracefork: unexpected result from waitpid "
4324 "(%d, status 0x%x)", ret
, status
);
4328 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4330 warning ("linux_test_for_tracefork: failed to kill child");
4331 my_waitpid (child_pid
, &status
, 0);
4333 while (WIFSTOPPED (status
));
4335 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4337 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4342 linux_look_up_symbols (void)
4344 #ifdef USE_THREAD_DB
4345 struct process_info
*proc
= current_process ();
4347 if (proc
->private->thread_db
!= NULL
)
4350 /* If the kernel supports tracing forks then it also supports tracing
4351 clones, and then we don't need to use the magic thread event breakpoint
4352 to learn about threads. */
4353 thread_db_init (!linux_supports_tracefork_flag
);
4358 linux_request_interrupt (void)
4360 extern unsigned long signal_pid
;
4362 if (!ptid_equal (cont_thread
, null_ptid
)
4363 && !ptid_equal (cont_thread
, minus_one_ptid
))
4365 struct lwp_info
*lwp
;
4368 lwp
= get_thread_lwp (current_inferior
);
4369 lwpid
= lwpid_of (lwp
);
4370 kill_lwp (lwpid
, SIGINT
);
4373 kill_lwp (signal_pid
, SIGINT
);
4376 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4377 to debugger memory starting at MYADDR. */
4380 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4382 char filename
[PATH_MAX
];
4384 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4386 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4388 fd
= open (filename
, O_RDONLY
);
4392 if (offset
!= (CORE_ADDR
) 0
4393 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4396 n
= read (fd
, myaddr
, len
);
4403 /* These breakpoint and watchpoint related wrapper functions simply
4404 pass on the function call if the target has registered a
4405 corresponding function. */
4408 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
4410 if (the_low_target
.insert_point
!= NULL
)
4411 return the_low_target
.insert_point (type
, addr
, len
);
4413 /* Unsupported (see target.h). */
4418 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
4420 if (the_low_target
.remove_point
!= NULL
)
4421 return the_low_target
.remove_point (type
, addr
, len
);
4423 /* Unsupported (see target.h). */
4428 linux_stopped_by_watchpoint (void)
4430 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4432 return lwp
->stopped_by_watchpoint
;
4436 linux_stopped_data_address (void)
4438 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4440 return lwp
->stopped_data_address
;
4443 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4444 #if defined(__mcoldfire__)
4445 /* These should really be defined in the kernel's ptrace.h header. */
4446 #define PT_TEXT_ADDR 49*4
4447 #define PT_DATA_ADDR 50*4
4448 #define PT_TEXT_END_ADDR 51*4
4450 #define PT_TEXT_ADDR 220
4451 #define PT_TEXT_END_ADDR 224
4452 #define PT_DATA_ADDR 228
4453 #elif defined(__TMS320C6X__)
4454 #define PT_TEXT_ADDR (0x10000*4)
4455 #define PT_DATA_ADDR (0x10004*4)
4456 #define PT_TEXT_END_ADDR (0x10008*4)
4459 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4460 to tell gdb about. */
4463 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
4465 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
4466 unsigned long text
, text_end
, data
;
4467 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4471 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
4472 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
4473 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
4477 /* Both text and data offsets produced at compile-time (and so
4478 used by gdb) are relative to the beginning of the program,
4479 with the data segment immediately following the text segment.
4480 However, the actual runtime layout in memory may put the data
4481 somewhere else, so when we send gdb a data base-address, we
4482 use the real data base address and subtract the compile-time
4483 data base-address from it (which is just the length of the
4484 text segment). BSS immediately follows data in both
4487 *data_p
= data
- (text_end
- text
);
4497 linux_qxfer_osdata (const char *annex
,
4498 unsigned char *readbuf
, unsigned const char *writebuf
,
4499 CORE_ADDR offset
, int len
)
4501 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
4504 /* Convert a native/host siginfo object, into/from the siginfo in the
4505 layout of the inferiors' architecture. */
4508 siginfo_fixup (struct siginfo
*siginfo
, void *inf_siginfo
, int direction
)
4512 if (the_low_target
.siginfo_fixup
!= NULL
)
4513 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4515 /* If there was no callback, or the callback didn't do anything,
4516 then just do a straight memcpy. */
4520 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
4522 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
4527 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
4528 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
4531 struct siginfo siginfo
;
4532 char inf_siginfo
[sizeof (struct siginfo
)];
4534 if (current_inferior
== NULL
)
4537 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4540 fprintf (stderr
, "%s siginfo for lwp %d.\n",
4541 readbuf
!= NULL
? "Reading" : "Writing",
4544 if (offset
>= sizeof (siginfo
))
4547 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
4550 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4551 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4552 inferior with a 64-bit GDBSERVER should look the same as debugging it
4553 with a 32-bit GDBSERVER, we need to convert it. */
4554 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4556 if (offset
+ len
> sizeof (siginfo
))
4557 len
= sizeof (siginfo
) - offset
;
4559 if (readbuf
!= NULL
)
4560 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4563 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4565 /* Convert back to ptrace layout before flushing it out. */
4566 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4568 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
4575 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4576 so we notice when children change state; as the handler for the
4577 sigsuspend in my_waitpid. */
4580 sigchld_handler (int signo
)
4582 int old_errno
= errno
;
4588 /* fprintf is not async-signal-safe, so call write
4590 if (write (2, "sigchld_handler\n",
4591 sizeof ("sigchld_handler\n") - 1) < 0)
4592 break; /* just ignore */
4596 if (target_is_async_p ())
4597 async_file_mark (); /* trigger a linux_wait */
4603 linux_supports_non_stop (void)
4609 linux_async (int enable
)
4611 int previous
= (linux_event_pipe
[0] != -1);
4614 fprintf (stderr
, "linux_async (%d), previous=%d\n",
4617 if (previous
!= enable
)
4620 sigemptyset (&mask
);
4621 sigaddset (&mask
, SIGCHLD
);
4623 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
4627 if (pipe (linux_event_pipe
) == -1)
4628 fatal ("creating event pipe failed.");
4630 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
4631 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
4633 /* Register the event loop handler. */
4634 add_file_handler (linux_event_pipe
[0],
4635 handle_target_event
, NULL
);
4637 /* Always trigger a linux_wait. */
4642 delete_file_handler (linux_event_pipe
[0]);
4644 close (linux_event_pipe
[0]);
4645 close (linux_event_pipe
[1]);
4646 linux_event_pipe
[0] = -1;
4647 linux_event_pipe
[1] = -1;
4650 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
4657 linux_start_non_stop (int nonstop
)
4659 /* Register or unregister from event-loop accordingly. */
4660 linux_async (nonstop
);
4665 linux_supports_multi_process (void)
4671 linux_supports_disable_randomization (void)
4673 #ifdef HAVE_PERSONALITY
4680 /* Enumerate spufs IDs for process PID. */
4682 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
4688 struct dirent
*entry
;
4690 sprintf (path
, "/proc/%ld/fd", pid
);
4691 dir
= opendir (path
);
4696 while ((entry
= readdir (dir
)) != NULL
)
4702 fd
= atoi (entry
->d_name
);
4706 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
4707 if (stat (path
, &st
) != 0)
4709 if (!S_ISDIR (st
.st_mode
))
4712 if (statfs (path
, &stfs
) != 0)
4714 if (stfs
.f_type
!= SPUFS_MAGIC
)
4717 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
4719 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
4729 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
4730 object type, using the /proc file system. */
4732 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
4733 unsigned const char *writebuf
,
4734 CORE_ADDR offset
, int len
)
4736 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
4741 if (!writebuf
&& !readbuf
)
4749 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
4752 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
4753 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
4758 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4765 ret
= write (fd
, writebuf
, (size_t) len
);
4767 ret
= read (fd
, readbuf
, (size_t) len
);
4773 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
4774 struct target_loadseg
4776 /* Core address to which the segment is mapped. */
4778 /* VMA recorded in the program header. */
4780 /* Size of this segment in memory. */
4784 # if defined PT_GETDSBT
4785 struct target_loadmap
4787 /* Protocol version number, must be zero. */
4789 /* Pointer to the DSBT table, its size, and the DSBT index. */
4790 unsigned *dsbt_table
;
4791 unsigned dsbt_size
, dsbt_index
;
4792 /* Number of segments in this map. */
4794 /* The actual memory map. */
4795 struct target_loadseg segs
[/*nsegs*/];
4797 # define LINUX_LOADMAP PT_GETDSBT
4798 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
4799 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
4801 struct target_loadmap
4803 /* Protocol version number, must be zero. */
4805 /* Number of segments in this map. */
4807 /* The actual memory map. */
4808 struct target_loadseg segs
[/*nsegs*/];
4810 # define LINUX_LOADMAP PTRACE_GETFDPIC
4811 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
4812 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
4816 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
4817 unsigned char *myaddr
, unsigned int len
)
4819 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4821 struct target_loadmap
*data
= NULL
;
4822 unsigned int actual_length
, copy_length
;
4824 if (strcmp (annex
, "exec") == 0)
4825 addr
= (int) LINUX_LOADMAP_EXEC
;
4826 else if (strcmp (annex
, "interp") == 0)
4827 addr
= (int) LINUX_LOADMAP_INTERP
;
4831 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
4837 actual_length
= sizeof (struct target_loadmap
)
4838 + sizeof (struct target_loadseg
) * data
->nsegs
;
4840 if (offset
< 0 || offset
> actual_length
)
4843 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
4844 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
4848 # define linux_read_loadmap NULL
4849 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
4852 linux_process_qsupported (const char *query
)
4854 if (the_low_target
.process_qsupported
!= NULL
)
4855 the_low_target
.process_qsupported (query
);
4859 linux_supports_tracepoints (void)
4861 if (*the_low_target
.supports_tracepoints
== NULL
)
4864 return (*the_low_target
.supports_tracepoints
) ();
4868 linux_read_pc (struct regcache
*regcache
)
4870 if (the_low_target
.get_pc
== NULL
)
4873 return (*the_low_target
.get_pc
) (regcache
);
4877 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
4879 gdb_assert (the_low_target
.set_pc
!= NULL
);
4881 (*the_low_target
.set_pc
) (regcache
, pc
);
4885 linux_thread_stopped (struct thread_info
*thread
)
4887 return get_thread_lwp (thread
)->stopped
;
4890 /* This exposes stop-all-threads functionality to other modules. */
4893 linux_pause_all (int freeze
)
4895 stop_all_lwps (freeze
, NULL
);
4898 /* This exposes unstop-all-threads functionality to other gdbserver
4902 linux_unpause_all (int unfreeze
)
4904 unstop_all_lwps (unfreeze
, NULL
);
4908 linux_prepare_to_access_memory (void)
4910 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
4913 linux_pause_all (1);
4918 linux_done_accessing_memory (void)
4920 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
4923 linux_unpause_all (1);
4927 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
4928 CORE_ADDR collector
,
4931 CORE_ADDR
*jump_entry
,
4932 CORE_ADDR
*trampoline
,
4933 ULONGEST
*trampoline_size
,
4934 unsigned char *jjump_pad_insn
,
4935 ULONGEST
*jjump_pad_insn_size
,
4936 CORE_ADDR
*adjusted_insn_addr
,
4937 CORE_ADDR
*adjusted_insn_addr_end
,
4940 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
4941 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
4942 jump_entry
, trampoline
, trampoline_size
,
4943 jjump_pad_insn
, jjump_pad_insn_size
,
4944 adjusted_insn_addr
, adjusted_insn_addr_end
,
4948 static struct emit_ops
*
4949 linux_emit_ops (void)
4951 if (the_low_target
.emit_ops
!= NULL
)
4952 return (*the_low_target
.emit_ops
) ();
4958 linux_get_min_fast_tracepoint_insn_len (void)
4960 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
4963 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
4966 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
4967 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
4969 char filename
[PATH_MAX
];
4971 const int auxv_size
= is_elf64
4972 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
4973 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
4975 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4977 fd
= open (filename
, O_RDONLY
);
4983 while (read (fd
, buf
, auxv_size
) == auxv_size
4984 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
4988 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
4990 switch (aux
->a_type
)
4993 *phdr_memaddr
= aux
->a_un
.a_val
;
4996 *num_phdr
= aux
->a_un
.a_val
;
5002 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5004 switch (aux
->a_type
)
5007 *phdr_memaddr
= aux
->a_un
.a_val
;
5010 *num_phdr
= aux
->a_un
.a_val
;
5018 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5020 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5021 "phdr_memaddr = %ld, phdr_num = %d",
5022 (long) *phdr_memaddr
, *num_phdr
);
5029 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5032 get_dynamic (const int pid
, const int is_elf64
)
5034 CORE_ADDR phdr_memaddr
, relocation
;
5036 unsigned char *phdr_buf
;
5037 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5039 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5042 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5043 phdr_buf
= alloca (num_phdr
* phdr_size
);
5045 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5048 /* Compute relocation: it is expected to be 0 for "regular" executables,
5049 non-zero for PIE ones. */
5051 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5054 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5056 if (p
->p_type
== PT_PHDR
)
5057 relocation
= phdr_memaddr
- p
->p_vaddr
;
5061 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5063 if (p
->p_type
== PT_PHDR
)
5064 relocation
= phdr_memaddr
- p
->p_vaddr
;
5067 if (relocation
== -1)
5069 warning ("Unexpected missing PT_PHDR");
5073 for (i
= 0; i
< num_phdr
; i
++)
5077 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5079 if (p
->p_type
== PT_DYNAMIC
)
5080 return p
->p_vaddr
+ relocation
;
5084 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5086 if (p
->p_type
== PT_DYNAMIC
)
5087 return p
->p_vaddr
+ relocation
;
5094 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5095 can be 0 if the inferior does not yet have the library list initialized. */
5098 get_r_debug (const int pid
, const int is_elf64
)
5100 CORE_ADDR dynamic_memaddr
;
5101 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5102 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5104 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5105 if (dynamic_memaddr
== 0)
5106 return (CORE_ADDR
) -1;
5108 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5112 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5114 if (dyn
->d_tag
== DT_DEBUG
)
5115 return dyn
->d_un
.d_val
;
5117 if (dyn
->d_tag
== DT_NULL
)
5122 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5124 if (dyn
->d_tag
== DT_DEBUG
)
5125 return dyn
->d_un
.d_val
;
5127 if (dyn
->d_tag
== DT_NULL
)
5131 dynamic_memaddr
+= dyn_size
;
5134 return (CORE_ADDR
) -1;
5137 /* Read one pointer from MEMADDR in the inferior. */
5140 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5143 return linux_read_memory (memaddr
, (unsigned char *) ptr
, ptr_size
);
5146 struct link_map_offsets
5148 /* Offset and size of r_debug.r_version. */
5149 int r_version_offset
;
5151 /* Offset and size of r_debug.r_map. */
5154 /* Offset to l_addr field in struct link_map. */
5157 /* Offset to l_name field in struct link_map. */
5160 /* Offset to l_ld field in struct link_map. */
5163 /* Offset to l_next field in struct link_map. */
5166 /* Offset to l_prev field in struct link_map. */
5170 /* Construct qXfer:libraries:read reply. */
5173 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5174 unsigned const char *writebuf
,
5175 CORE_ADDR offset
, int len
)
5178 unsigned document_len
;
5179 struct process_info_private
*const priv
= current_process ()->private;
5180 char filename
[PATH_MAX
];
5183 static const struct link_map_offsets lmo_32bit_offsets
=
5185 0, /* r_version offset. */
5186 4, /* r_debug.r_map offset. */
5187 0, /* l_addr offset in link_map. */
5188 4, /* l_name offset in link_map. */
5189 8, /* l_ld offset in link_map. */
5190 12, /* l_next offset in link_map. */
5191 16 /* l_prev offset in link_map. */
5194 static const struct link_map_offsets lmo_64bit_offsets
=
5196 0, /* r_version offset. */
5197 8, /* r_debug.r_map offset. */
5198 0, /* l_addr offset in link_map. */
5199 8, /* l_name offset in link_map. */
5200 16, /* l_ld offset in link_map. */
5201 24, /* l_next offset in link_map. */
5202 32 /* l_prev offset in link_map. */
5204 const struct link_map_offsets
*lmo
;
5206 if (writebuf
!= NULL
)
5208 if (readbuf
== NULL
)
5211 pid
= lwpid_of (get_thread_lwp (current_inferior
));
5212 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5213 is_elf64
= elf_64_file_p (filename
);
5214 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5216 if (priv
->r_debug
== 0)
5217 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5219 if (priv
->r_debug
== (CORE_ADDR
) -1 || priv
->r_debug
== 0)
5221 document
= xstrdup ("<library-list-svr4 version=\"1.0\"/>\n");
5225 int allocated
= 1024;
5227 const int ptr_size
= is_elf64
? 8 : 4;
5228 CORE_ADDR lm_addr
, lm_prev
, l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5229 int r_version
, header_done
= 0;
5231 document
= xmalloc (allocated
);
5232 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5233 p
= document
+ strlen (document
);
5236 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5237 (unsigned char *) &r_version
,
5238 sizeof (r_version
)) != 0
5241 warning ("unexpected r_debug version %d", r_version
);
5245 if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5246 &lm_addr
, ptr_size
) != 0)
5248 warning ("unable to read r_map from 0x%lx",
5249 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5254 while (read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5255 &l_name
, ptr_size
) == 0
5256 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5257 &l_addr
, ptr_size
) == 0
5258 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5259 &l_ld
, ptr_size
) == 0
5260 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5261 &l_prev
, ptr_size
) == 0
5262 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5263 &l_next
, ptr_size
) == 0)
5265 unsigned char libname
[PATH_MAX
];
5267 if (lm_prev
!= l_prev
)
5269 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5270 (long) lm_prev
, (long) l_prev
);
5274 /* Not checking for error because reading may stop before
5275 we've got PATH_MAX worth of characters. */
5277 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5278 libname
[sizeof (libname
) - 1] = '\0';
5279 if (libname
[0] != '\0')
5281 /* 6x the size for xml_escape_text below. */
5282 size_t len
= 6 * strlen ((char *) libname
);
5287 /* Terminate `<library-list-svr4'. */
5292 while (allocated
< p
- document
+ len
+ 200)
5294 /* Expand to guarantee sufficient storage. */
5295 uintptr_t document_len
= p
- document
;
5297 document
= xrealloc (document
, 2 * allocated
);
5299 p
= document
+ document_len
;
5302 name
= xml_escape_text ((char *) libname
);
5303 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
5304 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5305 name
, (unsigned long) lm_addr
,
5306 (unsigned long) l_addr
, (unsigned long) l_ld
);
5309 else if (lm_prev
== 0)
5311 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5322 strcpy (p
, "</library-list-svr4>");
5325 document_len
= strlen (document
);
5326 if (offset
< document_len
)
5327 document_len
-= offset
;
5330 if (len
> document_len
)
5333 memcpy (readbuf
, document
+ offset
, len
);
5339 static struct target_ops linux_target_ops
= {
5340 linux_create_inferior
,
5349 linux_fetch_registers
,
5350 linux_store_registers
,
5351 linux_prepare_to_access_memory
,
5352 linux_done_accessing_memory
,
5355 linux_look_up_symbols
,
5356 linux_request_interrupt
,
5360 linux_stopped_by_watchpoint
,
5361 linux_stopped_data_address
,
5362 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
5367 #ifdef USE_THREAD_DB
5368 thread_db_get_tls_address
,
5373 hostio_last_error_from_errno
,
5376 linux_supports_non_stop
,
5378 linux_start_non_stop
,
5379 linux_supports_multi_process
,
5380 #ifdef USE_THREAD_DB
5381 thread_db_handle_monitor_command
,
5385 linux_common_core_of_thread
,
5387 linux_process_qsupported
,
5388 linux_supports_tracepoints
,
5391 linux_thread_stopped
,
5395 linux_cancel_breakpoints
,
5396 linux_stabilize_threads
,
5397 linux_install_fast_tracepoint_jump_pad
,
5399 linux_supports_disable_randomization
,
5400 linux_get_min_fast_tracepoint_insn_len
,
5401 linux_qxfer_libraries_svr4
,
5405 linux_init_signals ()
5407 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5408 to find what the cancel signal actually is. */
5409 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
5410 signal (__SIGRTMIN
+1, SIG_IGN
);
5415 initialize_low (void)
5417 struct sigaction sigchld_action
;
5418 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
5419 set_target_ops (&linux_target_ops
);
5420 set_breakpoint_data (the_low_target
.breakpoint
,
5421 the_low_target
.breakpoint_len
);
5422 linux_init_signals ();
5423 linux_test_for_tracefork ();
5424 #ifdef HAVE_LINUX_REGSETS
5425 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
5427 disabled_regsets
= xmalloc (num_regsets
);
5430 sigchld_action
.sa_handler
= sigchld_handler
;
5431 sigemptyset (&sigchld_action
.sa_mask
);
5432 sigchld_action
.sa_flags
= SA_RESTART
;
5433 sigaction (SIGCHLD
, &sigchld_action
, NULL
);