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"
26 #include <sys/param.h>
27 #include <sys/ptrace.h>
28 #include "linux-ptrace.h"
29 #include "linux-procfs.h"
31 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
47 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
48 then ELFMAG0 will have been defined. If it didn't get included by
49 gdb_proc_service.h then including it will likely introduce a duplicate
50 definition of elf_fpregset_t. */
55 #define SPUFS_MAGIC 0x23c9b64e
58 #ifdef HAVE_PERSONALITY
59 # include <sys/personality.h>
60 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
61 # define ADDR_NO_RANDOMIZE 0x0040000
70 #define W_STOPCODE(sig) ((sig) << 8 | 0x7f)
73 /* This is the kernel's hard limit. Not to be confused with
80 #if !(defined(__UCLIBC_HAS_MMU__) || defined(__ARCH_HAS_MMU__))
85 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
86 representation of the thread ID.
88 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
89 the same as the LWP ID.
91 ``all_processes'' is keyed by the "overall process ID", which
92 GNU/Linux calls tgid, "thread group ID". */
94 struct inferior_list all_lwps
;
96 /* A list of all unknown processes which receive stop signals. Some
97 other process will presumably claim each of these as forked
98 children momentarily. */
100 struct simple_pid_list
102 /* The process ID. */
105 /* The status as reported by waitpid. */
109 struct simple_pid_list
*next
;
111 struct simple_pid_list
*stopped_pids
;
113 /* Trivial list manipulation functions to keep track of a list of new
114 stopped processes. */
117 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
119 struct simple_pid_list
*new_pid
= xmalloc (sizeof (struct simple_pid_list
));
122 new_pid
->status
= status
;
123 new_pid
->next
= *listp
;
128 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
130 struct simple_pid_list
**p
;
132 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
133 if ((*p
)->pid
== pid
)
135 struct simple_pid_list
*next
= (*p
)->next
;
137 *statusp
= (*p
)->status
;
145 /* FIXME this is a bit of a hack, and could be removed. */
146 int stopping_threads
;
148 /* FIXME make into a target method? */
149 int using_threads
= 1;
151 /* True if we're presently stabilizing threads (moving them out of
153 static int stabilizing_threads
;
155 /* This flag is true iff we've just created or attached to our first
156 inferior but it has not stopped yet. As soon as it does, we need
157 to call the low target's arch_setup callback. Doing this only on
158 the first inferior avoids reinializing the architecture on every
159 inferior, and avoids messing with the register caches of the
160 already running inferiors. NOTE: this assumes all inferiors under
161 control of gdbserver have the same architecture. */
162 static int new_inferior
;
164 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
165 int step
, int signal
, siginfo_t
*info
);
166 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
167 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
168 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
169 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
170 static void *add_lwp (ptid_t ptid
);
171 static int linux_stopped_by_watchpoint (void);
172 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
173 static void proceed_all_lwps (void);
174 static int finish_step_over (struct lwp_info
*lwp
);
175 static CORE_ADDR
get_stop_pc (struct lwp_info
*lwp
);
176 static int kill_lwp (unsigned long lwpid
, int signo
);
177 static void linux_enable_event_reporting (int pid
);
179 /* True if the low target can hardware single-step. Such targets
180 don't need a BREAKPOINT_REINSERT_ADDR callback. */
183 can_hardware_single_step (void)
185 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
188 /* True if the low target supports memory breakpoints. If so, we'll
189 have a GET_PC implementation. */
192 supports_breakpoints (void)
194 return (the_low_target
.get_pc
!= NULL
);
197 /* Returns true if this target can support fast tracepoints. This
198 does not mean that the in-process agent has been loaded in the
202 supports_fast_tracepoints (void)
204 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
207 struct pending_signals
211 struct pending_signals
*prev
;
214 #define PTRACE_ARG3_TYPE void *
215 #define PTRACE_ARG4_TYPE void *
216 #define PTRACE_XFER_TYPE long
218 #ifdef HAVE_LINUX_REGSETS
219 static char *disabled_regsets
;
220 static int num_regsets
;
223 /* The read/write ends of the pipe registered as waitable file in the
225 static int linux_event_pipe
[2] = { -1, -1 };
227 /* True if we're currently in async mode. */
228 #define target_is_async_p() (linux_event_pipe[0] != -1)
230 static void send_sigstop (struct lwp_info
*lwp
);
231 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
233 /* Return non-zero if HEADER is a 64-bit ELF file. */
236 elf_64_header_p (const Elf64_Ehdr
*header
)
238 return (header
->e_ident
[EI_MAG0
] == ELFMAG0
239 && header
->e_ident
[EI_MAG1
] == ELFMAG1
240 && header
->e_ident
[EI_MAG2
] == ELFMAG2
241 && header
->e_ident
[EI_MAG3
] == ELFMAG3
242 && header
->e_ident
[EI_CLASS
] == ELFCLASS64
);
245 /* Return non-zero if FILE is a 64-bit ELF file,
246 zero if the file is not a 64-bit ELF file,
247 and -1 if the file is not accessible or doesn't exist. */
250 elf_64_file_p (const char *file
)
255 fd
= open (file
, O_RDONLY
);
259 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
266 return elf_64_header_p (&header
);
269 /* Accepts an integer PID; Returns true if the executable PID is
270 running is a 64-bit ELF file.. */
273 linux_pid_exe_is_elf_64_file (int pid
)
275 char file
[MAXPATHLEN
];
277 sprintf (file
, "/proc/%d/exe", pid
);
278 return elf_64_file_p (file
);
282 delete_lwp (struct lwp_info
*lwp
)
284 remove_thread (get_lwp_thread (lwp
));
285 remove_inferior (&all_lwps
, &lwp
->head
);
286 free (lwp
->arch_private
);
290 /* Add a process to the common process list, and set its private
293 static struct process_info
*
294 linux_add_process (int pid
, int attached
)
296 struct process_info
*proc
;
298 /* Is this the first process? If so, then set the arch. */
299 if (all_processes
.head
== NULL
)
302 proc
= add_process (pid
, attached
);
303 proc
->private = xcalloc (1, sizeof (*proc
->private));
305 if (the_low_target
.new_process
!= NULL
)
306 proc
->private->arch_private
= the_low_target
.new_process ();
311 /* Wrapper function for waitpid which handles EINTR, and emulates
312 __WALL for systems where that is not available. */
315 my_waitpid (int pid
, int *status
, int flags
)
320 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
324 sigset_t block_mask
, org_mask
, wake_mask
;
327 wnohang
= (flags
& WNOHANG
) != 0;
328 flags
&= ~(__WALL
| __WCLONE
);
331 /* Block all signals while here. This avoids knowing about
332 LinuxThread's signals. */
333 sigfillset (&block_mask
);
334 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
336 /* ... except during the sigsuspend below. */
337 sigemptyset (&wake_mask
);
341 /* Since all signals are blocked, there's no need to check
343 ret
= waitpid (pid
, status
, flags
);
346 if (ret
== -1 && out_errno
!= ECHILD
)
351 if (flags
& __WCLONE
)
353 /* We've tried both flavors now. If WNOHANG is set,
354 there's nothing else to do, just bail out. */
359 fprintf (stderr
, "blocking\n");
361 /* Block waiting for signals. */
362 sigsuspend (&wake_mask
);
368 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
373 ret
= waitpid (pid
, status
, flags
);
374 while (ret
== -1 && errno
== EINTR
);
379 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
380 pid
, flags
, status
? *status
: -1, ret
);
386 /* Handle a GNU/Linux extended wait response. If we see a clone
387 event, we need to add the new LWP to our list (and not report the
388 trap to higher layers). */
391 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
393 int event
= wstat
>> 16;
394 struct lwp_info
*new_lwp
;
396 if (event
== PTRACE_EVENT_CLONE
)
399 unsigned long new_pid
;
402 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), 0, &new_pid
);
404 /* If we haven't already seen the new PID stop, wait for it now. */
405 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
407 /* The new child has a pending SIGSTOP. We can't affect it until it
408 hits the SIGSTOP, but we're already attached. */
410 ret
= my_waitpid (new_pid
, &status
, __WALL
);
413 perror_with_name ("waiting for new child");
414 else if (ret
!= new_pid
)
415 warning ("wait returned unexpected PID %d", ret
);
416 else if (!WIFSTOPPED (status
))
417 warning ("wait returned unexpected status 0x%x", status
);
420 linux_enable_event_reporting (new_pid
);
422 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
423 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
424 add_thread (ptid
, new_lwp
);
426 /* Either we're going to immediately resume the new thread
427 or leave it stopped. linux_resume_one_lwp is a nop if it
428 thinks the thread is currently running, so set this first
429 before calling linux_resume_one_lwp. */
430 new_lwp
->stopped
= 1;
432 /* Normally we will get the pending SIGSTOP. But in some cases
433 we might get another signal delivered to the group first.
434 If we do get another signal, be sure not to lose it. */
435 if (WSTOPSIG (status
) == SIGSTOP
)
437 if (stopping_threads
)
438 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
440 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
444 new_lwp
->stop_expected
= 1;
446 if (stopping_threads
)
448 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
449 new_lwp
->status_pending_p
= 1;
450 new_lwp
->status_pending
= status
;
453 /* Pass the signal on. This is what GDB does - except
454 shouldn't we really report it instead? */
455 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
458 /* Always resume the current thread. If we are stopping
459 threads, it will have a pending SIGSTOP; we may as well
461 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
465 /* Return the PC as read from the regcache of LWP, without any
469 get_pc (struct lwp_info
*lwp
)
471 struct thread_info
*saved_inferior
;
472 struct regcache
*regcache
;
475 if (the_low_target
.get_pc
== NULL
)
478 saved_inferior
= current_inferior
;
479 current_inferior
= get_lwp_thread (lwp
);
481 regcache
= get_thread_regcache (current_inferior
, 1);
482 pc
= (*the_low_target
.get_pc
) (regcache
);
485 fprintf (stderr
, "pc is 0x%lx\n", (long) pc
);
487 current_inferior
= saved_inferior
;
491 /* This function should only be called if LWP got a SIGTRAP.
492 The SIGTRAP could mean several things.
494 On i386, where decr_pc_after_break is non-zero:
495 If we were single-stepping this process using PTRACE_SINGLESTEP,
496 we will get only the one SIGTRAP (even if the instruction we
497 stepped over was a breakpoint). The value of $eip will be the
499 If we continue the process using PTRACE_CONT, we will get a
500 SIGTRAP when we hit a breakpoint. The value of $eip will be
501 the instruction after the breakpoint (i.e. needs to be
502 decremented). If we report the SIGTRAP to GDB, we must also
503 report the undecremented PC. If we cancel the SIGTRAP, we
504 must resume at the decremented PC.
506 (Presumably, not yet tested) On a non-decr_pc_after_break machine
507 with hardware or kernel single-step:
508 If we single-step over a breakpoint instruction, our PC will
509 point at the following instruction. If we continue and hit a
510 breakpoint instruction, our PC will point at the breakpoint
514 get_stop_pc (struct lwp_info
*lwp
)
518 if (the_low_target
.get_pc
== NULL
)
521 stop_pc
= get_pc (lwp
);
523 if (WSTOPSIG (lwp
->last_status
) == SIGTRAP
525 && !lwp
->stopped_by_watchpoint
526 && lwp
->last_status
>> 16 == 0)
527 stop_pc
-= the_low_target
.decr_pc_after_break
;
530 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
536 add_lwp (ptid_t ptid
)
538 struct lwp_info
*lwp
;
540 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
541 memset (lwp
, 0, sizeof (*lwp
));
545 if (the_low_target
.new_thread
!= NULL
)
546 lwp
->arch_private
= the_low_target
.new_thread ();
548 add_inferior_to_list (&all_lwps
, &lwp
->head
);
553 /* Start an inferior process and returns its pid.
554 ALLARGS is a vector of program-name and args. */
557 linux_create_inferior (char *program
, char **allargs
)
559 #ifdef HAVE_PERSONALITY
560 int personality_orig
= 0, personality_set
= 0;
562 struct lwp_info
*new_lwp
;
566 #ifdef HAVE_PERSONALITY
567 if (disable_randomization
)
570 personality_orig
= personality (0xffffffff);
571 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
574 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
576 if (errno
!= 0 || (personality_set
577 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
578 warning ("Error disabling address space randomization: %s",
583 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
589 perror_with_name ("fork");
593 ptrace (PTRACE_TRACEME
, 0, 0, 0);
595 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
596 signal (__SIGRTMIN
+ 1, SIG_DFL
);
601 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
602 stdout to stderr so that inferior i/o doesn't corrupt the connection.
603 Also, redirect stdin to /dev/null. */
604 if (remote_connection_is_stdio ())
607 open ("/dev/null", O_RDONLY
);
609 if (write (2, "stdin/stdout redirected\n",
610 sizeof ("stdin/stdout redirected\n") - 1) < 0)
611 /* Errors ignored. */;
614 execv (program
, allargs
);
616 execvp (program
, allargs
);
618 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
624 #ifdef HAVE_PERSONALITY
628 personality (personality_orig
);
630 warning ("Error restoring address space randomization: %s",
635 linux_add_process (pid
, 0);
637 ptid
= ptid_build (pid
, pid
, 0);
638 new_lwp
= add_lwp (ptid
);
639 add_thread (ptid
, new_lwp
);
640 new_lwp
->must_set_ptrace_flags
= 1;
645 /* Attach to an inferior process. */
648 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
651 struct lwp_info
*new_lwp
;
653 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) != 0)
657 /* If we fail to attach to an LWP, just warn. */
658 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
659 strerror (errno
), errno
);
664 /* If we fail to attach to a process, report an error. */
665 error ("Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
666 strerror (errno
), errno
);
670 /* If lwp is the tgid, we handle adding existing threads later.
671 Otherwise we just add lwp without bothering about any other
673 ptid
= ptid_build (lwpid
, lwpid
, 0);
676 /* Note that extracting the pid from the current inferior is
677 safe, since we're always called in the context of the same
678 process as this new thread. */
679 int pid
= pid_of (get_thread_lwp (current_inferior
));
680 ptid
= ptid_build (pid
, lwpid
, 0);
683 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
684 add_thread (ptid
, new_lwp
);
686 /* We need to wait for SIGSTOP before being able to make the next
687 ptrace call on this LWP. */
688 new_lwp
->must_set_ptrace_flags
= 1;
690 if (linux_proc_pid_is_stopped (lwpid
))
694 "Attached to a stopped process\n");
696 /* The process is definitely stopped. It is in a job control
697 stop, unless the kernel predates the TASK_STOPPED /
698 TASK_TRACED distinction, in which case it might be in a
699 ptrace stop. Make sure it is in a ptrace stop; from there we
700 can kill it, signal it, et cetera.
702 First make sure there is a pending SIGSTOP. Since we are
703 already attached, the process can not transition from stopped
704 to running without a PTRACE_CONT; so we know this signal will
705 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
706 probably already in the queue (unless this kernel is old
707 enough to use TASK_STOPPED for ptrace stops); but since
708 SIGSTOP is not an RT signal, it can only be queued once. */
709 kill_lwp (lwpid
, SIGSTOP
);
711 /* Finally, resume the stopped process. This will deliver the
712 SIGSTOP (or a higher priority signal, just like normal
713 PTRACE_ATTACH), which we'll catch later on. */
714 ptrace (PTRACE_CONT
, lwpid
, 0, 0);
717 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
720 There are several cases to consider here:
722 1) gdbserver has already attached to the process and is being notified
723 of a new thread that is being created.
724 In this case we should ignore that SIGSTOP and resume the
725 process. This is handled below by setting stop_expected = 1,
726 and the fact that add_thread sets last_resume_kind ==
729 2) This is the first thread (the process thread), and we're attaching
730 to it via attach_inferior.
731 In this case we want the process thread to stop.
732 This is handled by having linux_attach set last_resume_kind ==
733 resume_stop after we return.
735 If the pid we are attaching to is also the tgid, we attach to and
736 stop all the existing threads. Otherwise, we attach to pid and
737 ignore any other threads in the same group as this pid.
739 3) GDB is connecting to gdbserver and is requesting an enumeration of all
741 In this case we want the thread to stop.
742 FIXME: This case is currently not properly handled.
743 We should wait for the SIGSTOP but don't. Things work apparently
744 because enough time passes between when we ptrace (ATTACH) and when
745 gdb makes the next ptrace call on the thread.
747 On the other hand, if we are currently trying to stop all threads, we
748 should treat the new thread as if we had sent it a SIGSTOP. This works
749 because we are guaranteed that the add_lwp call above added us to the
750 end of the list, and so the new thread has not yet reached
751 wait_for_sigstop (but will). */
752 new_lwp
->stop_expected
= 1;
756 linux_attach_lwp (unsigned long lwpid
)
758 linux_attach_lwp_1 (lwpid
, 0);
761 /* Attach to PID. If PID is the tgid, attach to it and all
765 linux_attach (unsigned long pid
)
767 /* Attach to PID. We will check for other threads
769 linux_attach_lwp_1 (pid
, 1);
770 linux_add_process (pid
, 1);
774 struct thread_info
*thread
;
776 /* Don't ignore the initial SIGSTOP if we just attached to this
777 process. It will be collected by wait shortly. */
778 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
779 thread
->last_resume_kind
= resume_stop
;
782 if (linux_proc_get_tgid (pid
) == pid
)
787 sprintf (pathname
, "/proc/%ld/task", pid
);
789 dir
= opendir (pathname
);
793 fprintf (stderr
, "Could not open /proc/%ld/task.\n", pid
);
798 /* At this point we attached to the tgid. Scan the task for
801 int new_threads_found
;
805 while (iterations
< 2)
807 new_threads_found
= 0;
808 /* Add all the other threads. While we go through the
809 threads, new threads may be spawned. Cycle through
810 the list of threads until we have done two iterations without
811 finding new threads. */
812 while ((dp
= readdir (dir
)) != NULL
)
815 lwp
= strtoul (dp
->d_name
, NULL
, 10);
817 /* Is this a new thread? */
819 && find_thread_ptid (ptid_build (pid
, lwp
, 0)) == NULL
)
821 linux_attach_lwp_1 (lwp
, 0);
826 Found and attached to new lwp %ld\n", lwp
);
830 if (!new_threads_found
)
851 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
853 struct counter
*counter
= args
;
855 if (ptid_get_pid (entry
->id
) == counter
->pid
)
857 if (++counter
->count
> 1)
865 last_thread_of_process_p (struct thread_info
*thread
)
867 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
868 int pid
= ptid_get_pid (ptid
);
869 struct counter counter
= { pid
, 0 };
871 return (find_inferior (&all_threads
,
872 second_thread_of_pid_p
, &counter
) == NULL
);
878 linux_kill_one_lwp (struct lwp_info
*lwp
)
880 int pid
= lwpid_of (lwp
);
882 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
883 there is no signal context, and ptrace(PTRACE_KILL) (or
884 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
885 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
886 alternative is to kill with SIGKILL. We only need one SIGKILL
887 per process, not one for each thread. But since we still support
888 linuxthreads, and we also support debugging programs using raw
889 clone without CLONE_THREAD, we send one for each thread. For
890 years, we used PTRACE_KILL only, so we're being a bit paranoid
891 about some old kernels where PTRACE_KILL might work better
892 (dubious if there are any such, but that's why it's paranoia), so
893 we try SIGKILL first, PTRACE_KILL second, and so we're fine
900 "LKL: kill (SIGKILL) %s, 0, 0 (%s)\n",
901 target_pid_to_str (ptid_of (lwp
)),
902 errno
? strerror (errno
) : "OK");
905 ptrace (PTRACE_KILL
, pid
, 0, 0);
908 "LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
909 target_pid_to_str (ptid_of (lwp
)),
910 errno
? strerror (errno
) : "OK");
913 /* Callback for `find_inferior'. Kills an lwp of a given process,
914 except the leader. */
917 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
919 struct thread_info
*thread
= (struct thread_info
*) entry
;
920 struct lwp_info
*lwp
= get_thread_lwp (thread
);
922 int pid
= * (int *) args
;
924 if (ptid_get_pid (entry
->id
) != pid
)
927 /* We avoid killing the first thread here, because of a Linux kernel (at
928 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
929 the children get a chance to be reaped, it will remain a zombie
932 if (lwpid_of (lwp
) == pid
)
935 fprintf (stderr
, "lkop: is last of process %s\n",
936 target_pid_to_str (entry
->id
));
942 linux_kill_one_lwp (lwp
);
944 /* Make sure it died. The loop is most likely unnecessary. */
945 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
946 } while (pid
> 0 && WIFSTOPPED (wstat
));
954 struct process_info
*process
;
955 struct lwp_info
*lwp
;
959 process
= find_process_pid (pid
);
963 /* If we're killing a running inferior, make sure it is stopped
964 first, as PTRACE_KILL will not work otherwise. */
965 stop_all_lwps (0, NULL
);
967 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
969 /* See the comment in linux_kill_one_lwp. We did not kill the first
970 thread in the list, so do so now. */
971 lwp
= find_lwp_pid (pid_to_ptid (pid
));
976 fprintf (stderr
, "lk_1: cannot find lwp %ld, for pid: %d\n",
977 lwpid_of (lwp
), pid
);
982 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
983 lwpid_of (lwp
), pid
);
987 linux_kill_one_lwp (lwp
);
989 /* Make sure it died. The loop is most likely unnecessary. */
990 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
991 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
994 the_target
->mourn (process
);
996 /* Since we presently can only stop all lwps of all processes, we
997 need to unstop lwps of other processes. */
998 unstop_all_lwps (0, NULL
);
1003 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1005 struct thread_info
*thread
= (struct thread_info
*) entry
;
1006 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1007 int pid
= * (int *) args
;
1009 if (ptid_get_pid (entry
->id
) != pid
)
1012 /* If this process is stopped but is expecting a SIGSTOP, then make
1013 sure we take care of that now. This isn't absolutely guaranteed
1014 to collect the SIGSTOP, but is fairly likely to. */
1015 if (lwp
->stop_expected
)
1018 /* Clear stop_expected, so that the SIGSTOP will be reported. */
1019 lwp
->stop_expected
= 0;
1020 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
1021 linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
1024 /* Flush any pending changes to the process's registers. */
1025 regcache_invalidate_one ((struct inferior_list_entry
*)
1026 get_lwp_thread (lwp
));
1028 /* Finally, let it resume. */
1029 if (the_low_target
.prepare_to_resume
!= NULL
)
1030 the_low_target
.prepare_to_resume (lwp
);
1031 ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0, 0);
1038 linux_detach (int pid
)
1040 struct process_info
*process
;
1042 process
= find_process_pid (pid
);
1043 if (process
== NULL
)
1046 /* Stop all threads before detaching. First, ptrace requires that
1047 the thread is stopped to sucessfully detach. Second, thread_db
1048 may need to uninstall thread event breakpoints from memory, which
1049 only works with a stopped process anyway. */
1050 stop_all_lwps (0, NULL
);
1052 #ifdef USE_THREAD_DB
1053 thread_db_detach (process
);
1056 /* Stabilize threads (move out of jump pads). */
1057 stabilize_threads ();
1059 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1061 the_target
->mourn (process
);
1063 /* Since we presently can only stop all lwps of all processes, we
1064 need to unstop lwps of other processes. */
1065 unstop_all_lwps (0, NULL
);
1069 /* Remove all LWPs that belong to process PROC from the lwp list. */
1072 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1074 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1075 struct process_info
*process
= proc
;
1077 if (pid_of (lwp
) == pid_of (process
))
1084 linux_mourn (struct process_info
*process
)
1086 struct process_info_private
*priv
;
1088 #ifdef USE_THREAD_DB
1089 thread_db_mourn (process
);
1092 find_inferior (&all_lwps
, delete_lwp_callback
, process
);
1094 /* Freeing all private data. */
1095 priv
= process
->private;
1096 free (priv
->arch_private
);
1098 process
->private = NULL
;
1100 remove_process (process
);
1104 linux_join (int pid
)
1109 ret
= my_waitpid (pid
, &status
, 0);
1110 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1112 } while (ret
!= -1 || errno
!= ECHILD
);
1115 /* Return nonzero if the given thread is still alive. */
1117 linux_thread_alive (ptid_t ptid
)
1119 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1121 /* We assume we always know if a thread exits. If a whole process
1122 exited but we still haven't been able to report it to GDB, we'll
1123 hold on to the last lwp of the dead process. */
1130 /* Return 1 if this lwp has an interesting status pending. */
1132 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1134 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1135 ptid_t ptid
= * (ptid_t
*) arg
;
1136 struct thread_info
*thread
;
1138 /* Check if we're only interested in events from a specific process
1140 if (!ptid_equal (minus_one_ptid
, ptid
)
1141 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
1144 thread
= get_lwp_thread (lwp
);
1146 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1147 report any status pending the LWP may have. */
1148 if (thread
->last_resume_kind
== resume_stop
1149 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1152 return lwp
->status_pending_p
;
1156 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1158 ptid_t ptid
= *(ptid_t
*) data
;
1161 if (ptid_get_lwp (ptid
) != 0)
1162 lwp
= ptid_get_lwp (ptid
);
1164 lwp
= ptid_get_pid (ptid
);
1166 if (ptid_get_lwp (entry
->id
) == lwp
)
1173 find_lwp_pid (ptid_t ptid
)
1175 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
1178 static struct lwp_info
*
1179 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
1182 int to_wait_for
= -1;
1183 struct lwp_info
*child
= NULL
;
1186 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1188 if (ptid_equal (ptid
, minus_one_ptid
))
1189 to_wait_for
= -1; /* any child */
1191 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1197 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1198 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1201 perror_with_name ("waitpid");
1204 && (!WIFSTOPPED (*wstatp
)
1205 || (WSTOPSIG (*wstatp
) != 32
1206 && WSTOPSIG (*wstatp
) != 33)))
1207 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1209 child
= find_lwp_pid (pid_to_ptid (ret
));
1211 /* If we didn't find a process, one of two things presumably happened:
1212 - A process we started and then detached from has exited. Ignore it.
1213 - A process we are controlling has forked and the new child's stop
1214 was reported to us by the kernel. Save its PID. */
1215 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1217 add_to_pid_list (&stopped_pids
, ret
, *wstatp
);
1220 else if (child
== NULL
)
1225 child
->last_status
= *wstatp
;
1227 /* Architecture-specific setup after inferior is running.
1228 This needs to happen after we have attached to the inferior
1229 and it is stopped for the first time, but before we access
1230 any inferior registers. */
1233 the_low_target
.arch_setup ();
1234 #ifdef HAVE_LINUX_REGSETS
1235 memset (disabled_regsets
, 0, num_regsets
);
1240 /* Fetch the possibly triggered data watchpoint info and store it in
1243 On some archs, like x86, that use debug registers to set
1244 watchpoints, it's possible that the way to know which watched
1245 address trapped, is to check the register that is used to select
1246 which address to watch. Problem is, between setting the
1247 watchpoint and reading back which data address trapped, the user
1248 may change the set of watchpoints, and, as a consequence, GDB
1249 changes the debug registers in the inferior. To avoid reading
1250 back a stale stopped-data-address when that happens, we cache in
1251 LP the fact that a watchpoint trapped, and the corresponding data
1252 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1253 changes the debug registers meanwhile, we have the cached data we
1256 if (WIFSTOPPED (*wstatp
) && WSTOPSIG (*wstatp
) == SIGTRAP
)
1258 if (the_low_target
.stopped_by_watchpoint
== NULL
)
1260 child
->stopped_by_watchpoint
= 0;
1264 struct thread_info
*saved_inferior
;
1266 saved_inferior
= current_inferior
;
1267 current_inferior
= get_lwp_thread (child
);
1269 child
->stopped_by_watchpoint
1270 = the_low_target
.stopped_by_watchpoint ();
1272 if (child
->stopped_by_watchpoint
)
1274 if (the_low_target
.stopped_data_address
!= NULL
)
1275 child
->stopped_data_address
1276 = the_low_target
.stopped_data_address ();
1278 child
->stopped_data_address
= 0;
1281 current_inferior
= saved_inferior
;
1285 /* Store the STOP_PC, with adjustment applied. This depends on the
1286 architecture being defined already (so that CHILD has a valid
1287 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1289 if (WIFSTOPPED (*wstatp
))
1290 child
->stop_pc
= get_stop_pc (child
);
1293 && WIFSTOPPED (*wstatp
)
1294 && the_low_target
.get_pc
!= NULL
)
1296 struct thread_info
*saved_inferior
= current_inferior
;
1297 struct regcache
*regcache
;
1300 current_inferior
= get_lwp_thread (child
);
1301 regcache
= get_thread_regcache (current_inferior
, 1);
1302 pc
= (*the_low_target
.get_pc
) (regcache
);
1303 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1304 current_inferior
= saved_inferior
;
1310 /* This function should only be called if the LWP got a SIGTRAP.
1312 Handle any tracepoint steps or hits. Return true if a tracepoint
1313 event was handled, 0 otherwise. */
1316 handle_tracepoints (struct lwp_info
*lwp
)
1318 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1319 int tpoint_related_event
= 0;
1321 /* If this tracepoint hit causes a tracing stop, we'll immediately
1322 uninsert tracepoints. To do this, we temporarily pause all
1323 threads, unpatch away, and then unpause threads. We need to make
1324 sure the unpausing doesn't resume LWP too. */
1327 /* And we need to be sure that any all-threads-stopping doesn't try
1328 to move threads out of the jump pads, as it could deadlock the
1329 inferior (LWP could be in the jump pad, maybe even holding the
1332 /* Do any necessary step collect actions. */
1333 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1335 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1337 /* See if we just hit a tracepoint and do its main collect
1339 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1343 gdb_assert (lwp
->suspended
== 0);
1344 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1346 if (tpoint_related_event
)
1349 fprintf (stderr
, "got a tracepoint event\n");
1356 /* Convenience wrapper. Returns true if LWP is presently collecting a
1360 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1361 struct fast_tpoint_collect_status
*status
)
1363 CORE_ADDR thread_area
;
1365 if (the_low_target
.get_thread_area
== NULL
)
1368 /* Get the thread area address. This is used to recognize which
1369 thread is which when tracing with the in-process agent library.
1370 We don't read anything from the address, and treat it as opaque;
1371 it's the address itself that we assume is unique per-thread. */
1372 if ((*the_low_target
.get_thread_area
) (lwpid_of (lwp
), &thread_area
) == -1)
1375 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1378 /* The reason we resume in the caller, is because we want to be able
1379 to pass lwp->status_pending as WSTAT, and we need to clear
1380 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1381 refuses to resume. */
1384 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1386 struct thread_info
*saved_inferior
;
1388 saved_inferior
= current_inferior
;
1389 current_inferior
= get_lwp_thread (lwp
);
1392 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1393 && supports_fast_tracepoints ()
1394 && agent_loaded_p ())
1396 struct fast_tpoint_collect_status status
;
1401 Checking whether LWP %ld needs to move out of the jump pad.\n",
1404 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1407 || (WSTOPSIG (*wstat
) != SIGILL
1408 && WSTOPSIG (*wstat
) != SIGFPE
1409 && WSTOPSIG (*wstat
) != SIGSEGV
1410 && WSTOPSIG (*wstat
) != SIGBUS
))
1412 lwp
->collecting_fast_tracepoint
= r
;
1416 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1418 /* Haven't executed the original instruction yet.
1419 Set breakpoint there, and wait till it's hit,
1420 then single-step until exiting the jump pad. */
1421 lwp
->exit_jump_pad_bkpt
1422 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1427 Checking whether LWP %ld needs to move out of the jump pad...it does\n",
1429 current_inferior
= saved_inferior
;
1436 /* If we get a synchronous signal while collecting, *and*
1437 while executing the (relocated) original instruction,
1438 reset the PC to point at the tpoint address, before
1439 reporting to GDB. Otherwise, it's an IPA lib bug: just
1440 report the signal to GDB, and pray for the best. */
1442 lwp
->collecting_fast_tracepoint
= 0;
1445 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1446 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1449 struct regcache
*regcache
;
1451 /* The si_addr on a few signals references the address
1452 of the faulting instruction. Adjust that as
1454 if ((WSTOPSIG (*wstat
) == SIGILL
1455 || WSTOPSIG (*wstat
) == SIGFPE
1456 || WSTOPSIG (*wstat
) == SIGBUS
1457 || WSTOPSIG (*wstat
) == SIGSEGV
)
1458 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &info
) == 0
1459 /* Final check just to make sure we don't clobber
1460 the siginfo of non-kernel-sent signals. */
1461 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1463 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1464 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &info
);
1467 regcache
= get_thread_regcache (get_lwp_thread (lwp
), 1);
1468 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1469 lwp
->stop_pc
= status
.tpoint_addr
;
1471 /* Cancel any fast tracepoint lock this thread was
1473 force_unlock_trace_buffer ();
1476 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1480 "Cancelling fast exit-jump-pad: removing bkpt. "
1481 "stopping all threads momentarily.\n");
1483 stop_all_lwps (1, lwp
);
1484 cancel_breakpoints ();
1486 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1487 lwp
->exit_jump_pad_bkpt
= NULL
;
1489 unstop_all_lwps (1, lwp
);
1491 gdb_assert (lwp
->suspended
>= 0);
1498 Checking whether LWP %ld needs to move out of the jump pad...no\n",
1501 current_inferior
= saved_inferior
;
1505 /* Enqueue one signal in the "signals to report later when out of the
1509 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1511 struct pending_signals
*p_sig
;
1515 Deferring signal %d for LWP %ld.\n", WSTOPSIG (*wstat
), lwpid_of (lwp
));
1519 struct pending_signals
*sig
;
1521 for (sig
= lwp
->pending_signals_to_report
;
1525 " Already queued %d\n",
1528 fprintf (stderr
, " (no more currently queued signals)\n");
1531 /* Don't enqueue non-RT signals if they are already in the deferred
1532 queue. (SIGSTOP being the easiest signal to see ending up here
1534 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1536 struct pending_signals
*sig
;
1538 for (sig
= lwp
->pending_signals_to_report
;
1542 if (sig
->signal
== WSTOPSIG (*wstat
))
1546 "Not requeuing already queued non-RT signal %d"
1555 p_sig
= xmalloc (sizeof (*p_sig
));
1556 p_sig
->prev
= lwp
->pending_signals_to_report
;
1557 p_sig
->signal
= WSTOPSIG (*wstat
);
1558 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1559 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
1561 lwp
->pending_signals_to_report
= p_sig
;
1564 /* Dequeue one signal from the "signals to report later when out of
1565 the jump pad" list. */
1568 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1570 if (lwp
->pending_signals_to_report
!= NULL
)
1572 struct pending_signals
**p_sig
;
1574 p_sig
= &lwp
->pending_signals_to_report
;
1575 while ((*p_sig
)->prev
!= NULL
)
1576 p_sig
= &(*p_sig
)->prev
;
1578 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1579 if ((*p_sig
)->info
.si_signo
!= 0)
1580 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
1585 fprintf (stderr
, "Reporting deferred signal %d for LWP %ld.\n",
1586 WSTOPSIG (*wstat
), lwpid_of (lwp
));
1590 struct pending_signals
*sig
;
1592 for (sig
= lwp
->pending_signals_to_report
;
1596 " Still queued %d\n",
1599 fprintf (stderr
, " (no more queued signals)\n");
1608 /* Arrange for a breakpoint to be hit again later. We don't keep the
1609 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1610 will handle the current event, eventually we will resume this LWP,
1611 and this breakpoint will trap again. */
1614 cancel_breakpoint (struct lwp_info
*lwp
)
1616 struct thread_info
*saved_inferior
;
1618 /* There's nothing to do if we don't support breakpoints. */
1619 if (!supports_breakpoints ())
1622 /* breakpoint_at reads from current inferior. */
1623 saved_inferior
= current_inferior
;
1624 current_inferior
= get_lwp_thread (lwp
);
1626 if ((*the_low_target
.breakpoint_at
) (lwp
->stop_pc
))
1630 "CB: Push back breakpoint for %s\n",
1631 target_pid_to_str (ptid_of (lwp
)));
1633 /* Back up the PC if necessary. */
1634 if (the_low_target
.decr_pc_after_break
)
1636 struct regcache
*regcache
1637 = get_thread_regcache (current_inferior
, 1);
1638 (*the_low_target
.set_pc
) (regcache
, lwp
->stop_pc
);
1641 current_inferior
= saved_inferior
;
1648 "CB: No breakpoint found at %s for [%s]\n",
1649 paddress (lwp
->stop_pc
),
1650 target_pid_to_str (ptid_of (lwp
)));
1653 current_inferior
= saved_inferior
;
1657 /* When the event-loop is doing a step-over, this points at the thread
1659 ptid_t step_over_bkpt
;
1661 /* Wait for an event from child PID. If PID is -1, wait for any
1662 child. Store the stop status through the status pointer WSTAT.
1663 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1664 event was found and OPTIONS contains WNOHANG. Return the PID of
1665 the stopped child otherwise. */
1668 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1670 struct lwp_info
*event_child
, *requested_child
;
1674 requested_child
= NULL
;
1676 /* Check for a lwp with a pending status. */
1678 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
1680 event_child
= (struct lwp_info
*)
1681 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1682 if (debug_threads
&& event_child
)
1683 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1687 requested_child
= find_lwp_pid (ptid
);
1689 if (!stopping_threads
1690 && requested_child
->status_pending_p
1691 && requested_child
->collecting_fast_tracepoint
)
1693 enqueue_one_deferred_signal (requested_child
,
1694 &requested_child
->status_pending
);
1695 requested_child
->status_pending_p
= 0;
1696 requested_child
->status_pending
= 0;
1697 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
1700 if (requested_child
->suspended
1701 && requested_child
->status_pending_p
)
1702 fatal ("requesting an event out of a suspended child?");
1704 if (requested_child
->status_pending_p
)
1705 event_child
= requested_child
;
1708 if (event_child
!= NULL
)
1711 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1712 lwpid_of (event_child
), event_child
->status_pending
);
1713 *wstat
= event_child
->status_pending
;
1714 event_child
->status_pending_p
= 0;
1715 event_child
->status_pending
= 0;
1716 current_inferior
= get_lwp_thread (event_child
);
1717 return lwpid_of (event_child
);
1720 if (ptid_is_pid (ptid
))
1722 /* A request to wait for a specific tgid. This is not possible
1723 with waitpid, so instead, we wait for any child, and leave
1724 children we're not interested in right now with a pending
1725 status to report later. */
1726 wait_ptid
= minus_one_ptid
;
1731 /* We only enter this loop if no process has a pending wait status. Thus
1732 any action taken in response to a wait status inside this loop is
1733 responding as soon as we detect the status, not after any pending
1737 event_child
= linux_wait_for_lwp (wait_ptid
, wstat
, options
);
1739 if ((options
& WNOHANG
) && event_child
== NULL
)
1742 fprintf (stderr
, "WNOHANG set, no event found\n");
1746 if (event_child
== NULL
)
1747 error ("event from unknown child");
1749 if (ptid_is_pid (ptid
)
1750 && ptid_get_pid (ptid
) != ptid_get_pid (ptid_of (event_child
)))
1752 if (! WIFSTOPPED (*wstat
))
1753 mark_lwp_dead (event_child
, *wstat
);
1756 event_child
->status_pending_p
= 1;
1757 event_child
->status_pending
= *wstat
;
1762 current_inferior
= get_lwp_thread (event_child
);
1764 /* Check for thread exit. */
1765 if (! WIFSTOPPED (*wstat
))
1768 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1770 /* If the last thread is exiting, just return. */
1771 if (last_thread_of_process_p (current_inferior
))
1774 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1775 lwpid_of (event_child
));
1776 return lwpid_of (event_child
);
1781 current_inferior
= (struct thread_info
*) all_threads
.head
;
1783 fprintf (stderr
, "Current inferior is now %ld\n",
1784 lwpid_of (get_thread_lwp (current_inferior
)));
1788 current_inferior
= NULL
;
1790 fprintf (stderr
, "Current inferior is now <NULL>\n");
1793 /* If we were waiting for this particular child to do something...
1794 well, it did something. */
1795 if (requested_child
!= NULL
)
1797 int lwpid
= lwpid_of (event_child
);
1799 /* Cancel the step-over operation --- the thread that
1800 started it is gone. */
1801 if (finish_step_over (event_child
))
1802 unstop_all_lwps (1, event_child
);
1803 delete_lwp (event_child
);
1807 delete_lwp (event_child
);
1809 /* Wait for a more interesting event. */
1813 if (event_child
->must_set_ptrace_flags
)
1815 linux_enable_event_reporting (lwpid_of (event_child
));
1816 event_child
->must_set_ptrace_flags
= 0;
1819 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1820 && *wstat
>> 16 != 0)
1822 handle_extended_wait (event_child
, *wstat
);
1826 if (WIFSTOPPED (*wstat
)
1827 && WSTOPSIG (*wstat
) == SIGSTOP
1828 && event_child
->stop_expected
)
1833 fprintf (stderr
, "Expected stop.\n");
1834 event_child
->stop_expected
= 0;
1836 should_stop
= (current_inferior
->last_resume_kind
== resume_stop
1837 || stopping_threads
);
1841 linux_resume_one_lwp (event_child
,
1842 event_child
->stepping
, 0, NULL
);
1847 return lwpid_of (event_child
);
1854 /* Count the LWP's that have had events. */
1857 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
1859 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1860 struct thread_info
*thread
= get_lwp_thread (lp
);
1863 gdb_assert (count
!= NULL
);
1865 /* Count only resumed LWPs that have a SIGTRAP event pending that
1866 should be reported to GDB. */
1867 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1868 && thread
->last_resume_kind
!= resume_stop
1869 && lp
->status_pending_p
1870 && WIFSTOPPED (lp
->status_pending
)
1871 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1872 && !breakpoint_inserted_here (lp
->stop_pc
))
1878 /* Select the LWP (if any) that is currently being single-stepped. */
1881 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1883 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1884 struct thread_info
*thread
= get_lwp_thread (lp
);
1886 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1887 && thread
->last_resume_kind
== resume_step
1888 && lp
->status_pending_p
)
1894 /* Select the Nth LWP that has had a SIGTRAP event that should be
1898 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1900 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1901 struct thread_info
*thread
= get_lwp_thread (lp
);
1902 int *selector
= data
;
1904 gdb_assert (selector
!= NULL
);
1906 /* Select only resumed LWPs that have a SIGTRAP event pending. */
1907 if (thread
->last_resume_kind
!= resume_stop
1908 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1909 && lp
->status_pending_p
1910 && WIFSTOPPED (lp
->status_pending
)
1911 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1912 && !breakpoint_inserted_here (lp
->stop_pc
))
1913 if ((*selector
)-- == 0)
1920 cancel_breakpoints_callback (struct inferior_list_entry
*entry
, void *data
)
1922 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1923 struct thread_info
*thread
= get_lwp_thread (lp
);
1924 struct lwp_info
*event_lp
= data
;
1926 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
1930 /* If a LWP other than the LWP that we're reporting an event for has
1931 hit a GDB breakpoint (as opposed to some random trap signal),
1932 then just arrange for it to hit it again later. We don't keep
1933 the SIGTRAP status and don't forward the SIGTRAP signal to the
1934 LWP. We will handle the current event, eventually we will resume
1935 all LWPs, and this one will get its breakpoint trap again.
1937 If we do not do this, then we run the risk that the user will
1938 delete or disable the breakpoint, but the LWP will have already
1941 if (thread
->last_resume_kind
!= resume_stop
1942 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1943 && lp
->status_pending_p
1944 && WIFSTOPPED (lp
->status_pending
)
1945 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1947 && !lp
->stopped_by_watchpoint
1948 && cancel_breakpoint (lp
))
1949 /* Throw away the SIGTRAP. */
1950 lp
->status_pending_p
= 0;
1956 linux_cancel_breakpoints (void)
1958 find_inferior (&all_lwps
, cancel_breakpoints_callback
, NULL
);
1961 /* Select one LWP out of those that have events pending. */
1964 select_event_lwp (struct lwp_info
**orig_lp
)
1967 int random_selector
;
1968 struct lwp_info
*event_lp
;
1970 /* Give preference to any LWP that is being single-stepped. */
1972 = (struct lwp_info
*) find_inferior (&all_lwps
,
1973 select_singlestep_lwp_callback
, NULL
);
1974 if (event_lp
!= NULL
)
1978 "SEL: Select single-step %s\n",
1979 target_pid_to_str (ptid_of (event_lp
)));
1983 /* No single-stepping LWP. Select one at random, out of those
1984 which have had SIGTRAP events. */
1986 /* First see how many SIGTRAP events we have. */
1987 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
1989 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
1990 random_selector
= (int)
1991 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
1993 if (debug_threads
&& num_events
> 1)
1995 "SEL: Found %d SIGTRAP events, selecting #%d\n",
1996 num_events
, random_selector
);
1998 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
1999 select_event_lwp_callback
,
2003 if (event_lp
!= NULL
)
2005 /* Switch the event LWP. */
2006 *orig_lp
= event_lp
;
2010 /* Decrement the suspend count of an LWP. */
2013 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2015 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2017 /* Ignore EXCEPT. */
2023 gdb_assert (lwp
->suspended
>= 0);
2027 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2031 unsuspend_all_lwps (struct lwp_info
*except
)
2033 find_inferior (&all_lwps
, unsuspend_one_lwp
, except
);
2036 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2037 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2039 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2040 static ptid_t
linux_wait_1 (ptid_t ptid
,
2041 struct target_waitstatus
*ourstatus
,
2042 int target_options
);
2044 /* Stabilize threads (move out of jump pads).
2046 If a thread is midway collecting a fast tracepoint, we need to
2047 finish the collection and move it out of the jump pad before
2048 reporting the signal.
2050 This avoids recursion while collecting (when a signal arrives
2051 midway, and the signal handler itself collects), which would trash
2052 the trace buffer. In case the user set a breakpoint in a signal
2053 handler, this avoids the backtrace showing the jump pad, etc..
2054 Most importantly, there are certain things we can't do safely if
2055 threads are stopped in a jump pad (or in its callee's). For
2058 - starting a new trace run. A thread still collecting the
2059 previous run, could trash the trace buffer when resumed. The trace
2060 buffer control structures would have been reset but the thread had
2061 no way to tell. The thread could even midway memcpy'ing to the
2062 buffer, which would mean that when resumed, it would clobber the
2063 trace buffer that had been set for a new run.
2065 - we can't rewrite/reuse the jump pads for new tracepoints
2066 safely. Say you do tstart while a thread is stopped midway while
2067 collecting. When the thread is later resumed, it finishes the
2068 collection, and returns to the jump pad, to execute the original
2069 instruction that was under the tracepoint jump at the time the
2070 older run had been started. If the jump pad had been rewritten
2071 since for something else in the new run, the thread would now
2072 execute the wrong / random instructions. */
2075 linux_stabilize_threads (void)
2077 struct thread_info
*save_inferior
;
2078 struct lwp_info
*lwp_stuck
;
2081 = (struct lwp_info
*) find_inferior (&all_lwps
,
2082 stuck_in_jump_pad_callback
, NULL
);
2083 if (lwp_stuck
!= NULL
)
2086 fprintf (stderr
, "can't stabilize, LWP %ld is stuck in jump pad\n",
2087 lwpid_of (lwp_stuck
));
2091 save_inferior
= current_inferior
;
2093 stabilizing_threads
= 1;
2096 for_each_inferior (&all_lwps
, move_out_of_jump_pad_callback
);
2098 /* Loop until all are stopped out of the jump pads. */
2099 while (find_inferior (&all_lwps
, lwp_running
, NULL
) != NULL
)
2101 struct target_waitstatus ourstatus
;
2102 struct lwp_info
*lwp
;
2105 /* Note that we go through the full wait even loop. While
2106 moving threads out of jump pad, we need to be able to step
2107 over internal breakpoints and such. */
2108 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2110 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2112 lwp
= get_thread_lwp (current_inferior
);
2117 if (ourstatus
.value
.sig
!= TARGET_SIGNAL_0
2118 || current_inferior
->last_resume_kind
== resume_stop
)
2120 wstat
= W_STOPCODE (target_signal_to_host (ourstatus
.value
.sig
));
2121 enqueue_one_deferred_signal (lwp
, &wstat
);
2126 find_inferior (&all_lwps
, unsuspend_one_lwp
, NULL
);
2128 stabilizing_threads
= 0;
2130 current_inferior
= save_inferior
;
2135 = (struct lwp_info
*) find_inferior (&all_lwps
,
2136 stuck_in_jump_pad_callback
, NULL
);
2137 if (lwp_stuck
!= NULL
)
2138 fprintf (stderr
, "couldn't stabilize, LWP %ld got stuck in jump pad\n",
2139 lwpid_of (lwp_stuck
));
2143 /* Wait for process, returns status. */
2146 linux_wait_1 (ptid_t ptid
,
2147 struct target_waitstatus
*ourstatus
, int target_options
)
2150 struct lwp_info
*event_child
;
2153 int step_over_finished
;
2154 int bp_explains_trap
;
2155 int maybe_internal_trap
;
2159 /* Translate generic target options into linux options. */
2161 if (target_options
& TARGET_WNOHANG
)
2165 bp_explains_trap
= 0;
2167 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2169 /* If we were only supposed to resume one thread, only wait for
2170 that thread - if it's still alive. If it died, however - which
2171 can happen if we're coming from the thread death case below -
2172 then we need to make sure we restart the other threads. We could
2173 pick a thread at random or restart all; restarting all is less
2176 && !ptid_equal (cont_thread
, null_ptid
)
2177 && !ptid_equal (cont_thread
, minus_one_ptid
))
2179 struct thread_info
*thread
;
2181 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
2184 /* No stepping, no signal - unless one is pending already, of course. */
2187 struct thread_resume resume_info
;
2188 resume_info
.thread
= minus_one_ptid
;
2189 resume_info
.kind
= resume_continue
;
2190 resume_info
.sig
= 0;
2191 linux_resume (&resume_info
, 1);
2197 if (ptid_equal (step_over_bkpt
, null_ptid
))
2198 pid
= linux_wait_for_event (ptid
, &w
, options
);
2202 fprintf (stderr
, "step_over_bkpt set [%s], doing a blocking wait\n",
2203 target_pid_to_str (step_over_bkpt
));
2204 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2207 if (pid
== 0) /* only if TARGET_WNOHANG */
2210 event_child
= get_thread_lwp (current_inferior
);
2212 /* If we are waiting for a particular child, and it exited,
2213 linux_wait_for_event will return its exit status. Similarly if
2214 the last child exited. If this is not the last child, however,
2215 do not report it as exited until there is a 'thread exited' response
2216 available in the remote protocol. Instead, just wait for another event.
2217 This should be safe, because if the thread crashed we will already
2218 have reported the termination signal to GDB; that should stop any
2219 in-progress stepping operations, etc.
2221 Report the exit status of the last thread to exit. This matches
2222 LinuxThreads' behavior. */
2224 if (last_thread_of_process_p (current_inferior
))
2226 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2230 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2231 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2235 "\nChild exited with retcode = %x \n",
2240 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2241 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
2245 "\nChild terminated with signal = %x \n",
2250 return ptid_of (event_child
);
2255 if (!WIFSTOPPED (w
))
2259 /* If this event was not handled before, and is not a SIGTRAP, we
2260 report it. SIGILL and SIGSEGV are also treated as traps in case
2261 a breakpoint is inserted at the current PC. If this target does
2262 not support internal breakpoints at all, we also report the
2263 SIGTRAP without further processing; it's of no concern to us. */
2265 = (supports_breakpoints ()
2266 && (WSTOPSIG (w
) == SIGTRAP
2267 || ((WSTOPSIG (w
) == SIGILL
2268 || WSTOPSIG (w
) == SIGSEGV
)
2269 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2271 if (maybe_internal_trap
)
2273 /* Handle anything that requires bookkeeping before deciding to
2274 report the event or continue waiting. */
2276 /* First check if we can explain the SIGTRAP with an internal
2277 breakpoint, or if we should possibly report the event to GDB.
2278 Do this before anything that may remove or insert a
2280 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2282 /* We have a SIGTRAP, possibly a step-over dance has just
2283 finished. If so, tweak the state machine accordingly,
2284 reinsert breakpoints and delete any reinsert (software
2285 single-step) breakpoints. */
2286 step_over_finished
= finish_step_over (event_child
);
2288 /* Now invoke the callbacks of any internal breakpoints there. */
2289 check_breakpoints (event_child
->stop_pc
);
2291 /* Handle tracepoint data collecting. This may overflow the
2292 trace buffer, and cause a tracing stop, removing
2294 trace_event
= handle_tracepoints (event_child
);
2296 if (bp_explains_trap
)
2298 /* If we stepped or ran into an internal breakpoint, we've
2299 already handled it. So next time we resume (from this
2300 PC), we should step over it. */
2302 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2304 if (breakpoint_here (event_child
->stop_pc
))
2305 event_child
->need_step_over
= 1;
2310 /* We have some other signal, possibly a step-over dance was in
2311 progress, and it should be cancelled too. */
2312 step_over_finished
= finish_step_over (event_child
);
2315 /* We have all the data we need. Either report the event to GDB, or
2316 resume threads and keep waiting for more. */
2318 /* If we're collecting a fast tracepoint, finish the collection and
2319 move out of the jump pad before delivering a signal. See
2320 linux_stabilize_threads. */
2323 && WSTOPSIG (w
) != SIGTRAP
2324 && supports_fast_tracepoints ()
2325 && agent_loaded_p ())
2329 "Got signal %d for LWP %ld. Check if we need "
2330 "to defer or adjust it.\n",
2331 WSTOPSIG (w
), lwpid_of (event_child
));
2333 /* Allow debugging the jump pad itself. */
2334 if (current_inferior
->last_resume_kind
!= resume_step
2335 && maybe_move_out_of_jump_pad (event_child
, &w
))
2337 enqueue_one_deferred_signal (event_child
, &w
);
2341 "Signal %d for LWP %ld deferred (in jump pad)\n",
2342 WSTOPSIG (w
), lwpid_of (event_child
));
2344 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2349 if (event_child
->collecting_fast_tracepoint
)
2353 LWP %ld was trying to move out of the jump pad (%d). \
2354 Check if we're already there.\n",
2355 lwpid_of (event_child
),
2356 event_child
->collecting_fast_tracepoint
);
2360 event_child
->collecting_fast_tracepoint
2361 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2363 if (event_child
->collecting_fast_tracepoint
!= 1)
2365 /* No longer need this breakpoint. */
2366 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2370 "No longer need exit-jump-pad bkpt; removing it."
2371 "stopping all threads momentarily.\n");
2373 /* Other running threads could hit this breakpoint.
2374 We don't handle moribund locations like GDB does,
2375 instead we always pause all threads when removing
2376 breakpoints, so that any step-over or
2377 decr_pc_after_break adjustment is always taken
2378 care of while the breakpoint is still
2380 stop_all_lwps (1, event_child
);
2381 cancel_breakpoints ();
2383 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2384 event_child
->exit_jump_pad_bkpt
= NULL
;
2386 unstop_all_lwps (1, event_child
);
2388 gdb_assert (event_child
->suspended
>= 0);
2392 if (event_child
->collecting_fast_tracepoint
== 0)
2396 "fast tracepoint finished "
2397 "collecting successfully.\n");
2399 /* We may have a deferred signal to report. */
2400 if (dequeue_one_deferred_signal (event_child
, &w
))
2403 fprintf (stderr
, "dequeued one signal.\n");
2408 fprintf (stderr
, "no deferred signals.\n");
2410 if (stabilizing_threads
)
2412 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2413 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2414 return ptid_of (event_child
);
2420 /* Check whether GDB would be interested in this event. */
2422 /* If GDB is not interested in this signal, don't stop other
2423 threads, and don't report it to GDB. Just resume the inferior
2424 right away. We do this for threading-related signals as well as
2425 any that GDB specifically requested we ignore. But never ignore
2426 SIGSTOP if we sent it ourselves, and do not ignore signals when
2427 stepping - they may require special handling to skip the signal
2429 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2432 && current_inferior
->last_resume_kind
!= resume_step
2434 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2435 (current_process ()->private->thread_db
!= NULL
2436 && (WSTOPSIG (w
) == __SIGRTMIN
2437 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2440 (pass_signals
[target_signal_from_host (WSTOPSIG (w
))]
2441 && !(WSTOPSIG (w
) == SIGSTOP
2442 && current_inferior
->last_resume_kind
== resume_stop
))))
2444 siginfo_t info
, *info_p
;
2447 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
2448 WSTOPSIG (w
), lwpid_of (event_child
));
2450 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
2454 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2455 WSTOPSIG (w
), info_p
);
2459 /* If GDB wanted this thread to single step, we always want to
2460 report the SIGTRAP, and let GDB handle it. Watchpoints should
2461 always be reported. So should signals we can't explain. A
2462 SIGTRAP we can't explain could be a GDB breakpoint --- we may or
2463 not support Z0 breakpoints. If we do, we're be able to handle
2464 GDB breakpoints on top of internal breakpoints, by handling the
2465 internal breakpoint and still reporting the event to GDB. If we
2466 don't, we're out of luck, GDB won't see the breakpoint hit. */
2467 report_to_gdb
= (!maybe_internal_trap
2468 || current_inferior
->last_resume_kind
== resume_step
2469 || event_child
->stopped_by_watchpoint
2470 || (!step_over_finished
2471 && !bp_explains_trap
&& !trace_event
)
2472 || (gdb_breakpoint_here (event_child
->stop_pc
)
2473 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)));
2475 /* We found no reason GDB would want us to stop. We either hit one
2476 of our own breakpoints, or finished an internal step GDB
2477 shouldn't know about. */
2482 if (bp_explains_trap
)
2483 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2484 if (step_over_finished
)
2485 fprintf (stderr
, "Step-over finished.\n");
2487 fprintf (stderr
, "Tracepoint event.\n");
2490 /* We're not reporting this breakpoint to GDB, so apply the
2491 decr_pc_after_break adjustment to the inferior's regcache
2494 if (the_low_target
.set_pc
!= NULL
)
2496 struct regcache
*regcache
2497 = get_thread_regcache (get_lwp_thread (event_child
), 1);
2498 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2501 /* We may have finished stepping over a breakpoint. If so,
2502 we've stopped and suspended all LWPs momentarily except the
2503 stepping one. This is where we resume them all again. We're
2504 going to keep waiting, so use proceed, which handles stepping
2505 over the next breakpoint. */
2507 fprintf (stderr
, "proceeding all threads.\n");
2509 if (step_over_finished
)
2510 unsuspend_all_lwps (event_child
);
2512 proceed_all_lwps ();
2518 if (current_inferior
->last_resume_kind
== resume_step
)
2519 fprintf (stderr
, "GDB wanted to single-step, reporting event.\n");
2520 if (event_child
->stopped_by_watchpoint
)
2521 fprintf (stderr
, "Stopped by watchpoint.\n");
2522 if (gdb_breakpoint_here (event_child
->stop_pc
))
2523 fprintf (stderr
, "Stopped by GDB breakpoint.\n");
2525 fprintf (stderr
, "Hit a non-gdbserver trap event.\n");
2528 /* Alright, we're going to report a stop. */
2530 if (!non_stop
&& !stabilizing_threads
)
2532 /* In all-stop, stop all threads. */
2533 stop_all_lwps (0, NULL
);
2535 /* If we're not waiting for a specific LWP, choose an event LWP
2536 from among those that have had events. Giving equal priority
2537 to all LWPs that have had events helps prevent
2539 if (ptid_equal (ptid
, minus_one_ptid
))
2541 event_child
->status_pending_p
= 1;
2542 event_child
->status_pending
= w
;
2544 select_event_lwp (&event_child
);
2546 event_child
->status_pending_p
= 0;
2547 w
= event_child
->status_pending
;
2550 /* Now that we've selected our final event LWP, cancel any
2551 breakpoints in other LWPs that have hit a GDB breakpoint.
2552 See the comment in cancel_breakpoints_callback to find out
2554 find_inferior (&all_lwps
, cancel_breakpoints_callback
, event_child
);
2556 /* If we were going a step-over, all other threads but the stepping one
2557 had been paused in start_step_over, with their suspend counts
2558 incremented. We don't want to do a full unstop/unpause, because we're
2559 in all-stop mode (so we want threads stopped), but we still need to
2560 unsuspend the other threads, to decrement their `suspended' count
2562 if (step_over_finished
)
2563 unsuspend_all_lwps (event_child
);
2565 /* Stabilize threads (move out of jump pads). */
2566 stabilize_threads ();
2570 /* If we just finished a step-over, then all threads had been
2571 momentarily paused. In all-stop, that's fine, we want
2572 threads stopped by now anyway. In non-stop, we need to
2573 re-resume threads that GDB wanted to be running. */
2574 if (step_over_finished
)
2575 unstop_all_lwps (1, event_child
);
2578 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2580 if (current_inferior
->last_resume_kind
== resume_stop
2581 && WSTOPSIG (w
) == SIGSTOP
)
2583 /* A thread that has been requested to stop by GDB with vCont;t,
2584 and it stopped cleanly, so report as SIG0. The use of
2585 SIGSTOP is an implementation detail. */
2586 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2588 else if (current_inferior
->last_resume_kind
== resume_stop
2589 && WSTOPSIG (w
) != SIGSTOP
)
2591 /* A thread that has been requested to stop by GDB with vCont;t,
2592 but, it stopped for other reasons. */
2593 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2597 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2600 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
2603 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
2604 target_pid_to_str (ptid_of (event_child
)),
2606 ourstatus
->value
.sig
);
2608 return ptid_of (event_child
);
2611 /* Get rid of any pending event in the pipe. */
2613 async_file_flush (void)
2619 ret
= read (linux_event_pipe
[0], &buf
, 1);
2620 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
2623 /* Put something in the pipe, so the event loop wakes up. */
2625 async_file_mark (void)
2629 async_file_flush ();
2632 ret
= write (linux_event_pipe
[1], "+", 1);
2633 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
2635 /* Ignore EAGAIN. If the pipe is full, the event loop will already
2636 be awakened anyway. */
2640 linux_wait (ptid_t ptid
,
2641 struct target_waitstatus
*ourstatus
, int target_options
)
2646 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
2648 /* Flush the async file first. */
2649 if (target_is_async_p ())
2650 async_file_flush ();
2652 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
2654 /* If at least one stop was reported, there may be more. A single
2655 SIGCHLD can signal more than one child stop. */
2656 if (target_is_async_p ()
2657 && (target_options
& TARGET_WNOHANG
) != 0
2658 && !ptid_equal (event_ptid
, null_ptid
))
2664 /* Send a signal to an LWP. */
2667 kill_lwp (unsigned long lwpid
, int signo
)
2669 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2670 fails, then we are not using nptl threads and we should be using kill. */
2674 static int tkill_failed
;
2681 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2682 if (errno
!= ENOSYS
)
2689 return kill (lwpid
, signo
);
2693 linux_stop_lwp (struct lwp_info
*lwp
)
2699 send_sigstop (struct lwp_info
*lwp
)
2703 pid
= lwpid_of (lwp
);
2705 /* If we already have a pending stop signal for this process, don't
2707 if (lwp
->stop_expected
)
2710 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
2716 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
2718 lwp
->stop_expected
= 1;
2719 kill_lwp (pid
, SIGSTOP
);
2723 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
2725 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2727 /* Ignore EXCEPT. */
2738 /* Increment the suspend count of an LWP, and stop it, if not stopped
2741 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
2744 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2746 /* Ignore EXCEPT. */
2752 return send_sigstop_callback (entry
, except
);
2756 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
2758 /* It's dead, really. */
2761 /* Store the exit status for later. */
2762 lwp
->status_pending_p
= 1;
2763 lwp
->status_pending
= wstat
;
2765 /* Prevent trying to stop it. */
2768 /* No further stops are expected from a dead lwp. */
2769 lwp
->stop_expected
= 0;
2773 wait_for_sigstop (struct inferior_list_entry
*entry
)
2775 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2776 struct thread_info
*saved_inferior
;
2785 fprintf (stderr
, "wait_for_sigstop: LWP %ld already stopped\n",
2790 saved_inferior
= current_inferior
;
2791 if (saved_inferior
!= NULL
)
2792 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
2794 saved_tid
= null_ptid
; /* avoid bogus unused warning */
2796 ptid
= lwp
->head
.id
;
2799 fprintf (stderr
, "wait_for_sigstop: pulling one event\n");
2801 pid
= linux_wait_for_event (ptid
, &wstat
, __WALL
);
2803 /* If we stopped with a non-SIGSTOP signal, save it for later
2804 and record the pending SIGSTOP. If the process exited, just
2806 if (WIFSTOPPED (wstat
))
2809 fprintf (stderr
, "LWP %ld stopped with signal %d\n",
2810 lwpid_of (lwp
), WSTOPSIG (wstat
));
2812 if (WSTOPSIG (wstat
) != SIGSTOP
)
2815 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
2816 lwpid_of (lwp
), wstat
);
2818 lwp
->status_pending_p
= 1;
2819 lwp
->status_pending
= wstat
;
2825 fprintf (stderr
, "Process %d exited while stopping LWPs\n", pid
);
2827 lwp
= find_lwp_pid (pid_to_ptid (pid
));
2830 /* Leave this status pending for the next time we're able to
2831 report it. In the mean time, we'll report this lwp as
2832 dead to GDB, so GDB doesn't try to read registers and
2833 memory from it. This can only happen if this was the
2834 last thread of the process; otherwise, PID is removed
2835 from the thread tables before linux_wait_for_event
2837 mark_lwp_dead (lwp
, wstat
);
2841 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
2842 current_inferior
= saved_inferior
;
2846 fprintf (stderr
, "Previously current thread died.\n");
2850 /* We can't change the current inferior behind GDB's back,
2851 otherwise, a subsequent command may apply to the wrong
2853 current_inferior
= NULL
;
2857 /* Set a valid thread as current. */
2858 set_desired_inferior (0);
2863 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
2864 move it out, because we need to report the stop event to GDB. For
2865 example, if the user puts a breakpoint in the jump pad, it's
2866 because she wants to debug it. */
2869 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
2871 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2872 struct thread_info
*thread
= get_lwp_thread (lwp
);
2874 gdb_assert (lwp
->suspended
== 0);
2875 gdb_assert (lwp
->stopped
);
2877 /* Allow debugging the jump pad, gdb_collect, etc.. */
2878 return (supports_fast_tracepoints ()
2879 && agent_loaded_p ()
2880 && (gdb_breakpoint_here (lwp
->stop_pc
)
2881 || lwp
->stopped_by_watchpoint
2882 || thread
->last_resume_kind
== resume_step
)
2883 && linux_fast_tracepoint_collecting (lwp
, NULL
));
2887 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
2889 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2890 struct thread_info
*thread
= get_lwp_thread (lwp
);
2893 gdb_assert (lwp
->suspended
== 0);
2894 gdb_assert (lwp
->stopped
);
2896 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
2898 /* Allow debugging the jump pad, gdb_collect, etc. */
2899 if (!gdb_breakpoint_here (lwp
->stop_pc
)
2900 && !lwp
->stopped_by_watchpoint
2901 && thread
->last_resume_kind
!= resume_step
2902 && maybe_move_out_of_jump_pad (lwp
, wstat
))
2906 "LWP %ld needs stabilizing (in jump pad)\n",
2911 lwp
->status_pending_p
= 0;
2912 enqueue_one_deferred_signal (lwp
, wstat
);
2916 "Signal %d for LWP %ld deferred "
2918 WSTOPSIG (*wstat
), lwpid_of (lwp
));
2921 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
2928 lwp_running (struct inferior_list_entry
*entry
, void *data
)
2930 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2939 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
2940 If SUSPEND, then also increase the suspend count of every LWP,
2944 stop_all_lwps (int suspend
, struct lwp_info
*except
)
2946 stopping_threads
= 1;
2949 find_inferior (&all_lwps
, suspend_and_send_sigstop_callback
, except
);
2951 find_inferior (&all_lwps
, send_sigstop_callback
, except
);
2952 for_each_inferior (&all_lwps
, wait_for_sigstop
);
2953 stopping_threads
= 0;
2956 /* Resume execution of the inferior process.
2957 If STEP is nonzero, single-step it.
2958 If SIGNAL is nonzero, give it that signal. */
2961 linux_resume_one_lwp (struct lwp_info
*lwp
,
2962 int step
, int signal
, siginfo_t
*info
)
2964 struct thread_info
*saved_inferior
;
2965 int fast_tp_collecting
;
2967 if (lwp
->stopped
== 0)
2970 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
2972 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
2974 /* Cancel actions that rely on GDB not changing the PC (e.g., the
2975 user used the "jump" command, or "set $pc = foo"). */
2976 if (lwp
->stop_pc
!= get_pc (lwp
))
2978 /* Collecting 'while-stepping' actions doesn't make sense
2980 release_while_stepping_state_list (get_lwp_thread (lwp
));
2983 /* If we have pending signals or status, and a new signal, enqueue the
2984 signal. Also enqueue the signal if we are waiting to reinsert a
2985 breakpoint; it will be picked up again below. */
2987 && (lwp
->status_pending_p
2988 || lwp
->pending_signals
!= NULL
2989 || lwp
->bp_reinsert
!= 0
2990 || fast_tp_collecting
))
2992 struct pending_signals
*p_sig
;
2993 p_sig
= xmalloc (sizeof (*p_sig
));
2994 p_sig
->prev
= lwp
->pending_signals
;
2995 p_sig
->signal
= signal
;
2997 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
2999 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3000 lwp
->pending_signals
= p_sig
;
3003 if (lwp
->status_pending_p
)
3006 fprintf (stderr
, "Not resuming lwp %ld (%s, signal %d, stop %s);"
3007 " has pending status\n",
3008 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3009 lwp
->stop_expected
? "expected" : "not expected");
3013 saved_inferior
= current_inferior
;
3014 current_inferior
= get_lwp_thread (lwp
);
3017 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
3018 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3019 lwp
->stop_expected
? "expected" : "not expected");
3021 /* This bit needs some thinking about. If we get a signal that
3022 we must report while a single-step reinsert is still pending,
3023 we often end up resuming the thread. It might be better to
3024 (ew) allow a stack of pending events; then we could be sure that
3025 the reinsert happened right away and not lose any signals.
3027 Making this stack would also shrink the window in which breakpoints are
3028 uninserted (see comment in linux_wait_for_lwp) but not enough for
3029 complete correctness, so it won't solve that problem. It may be
3030 worthwhile just to solve this one, however. */
3031 if (lwp
->bp_reinsert
!= 0)
3034 fprintf (stderr
, " pending reinsert at 0x%s\n",
3035 paddress (lwp
->bp_reinsert
));
3037 if (lwp
->bp_reinsert
!= 0 && can_hardware_single_step ())
3039 if (fast_tp_collecting
== 0)
3042 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
3044 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
3051 /* Postpone any pending signal. It was enqueued above. */
3055 if (fast_tp_collecting
== 1)
3059 lwp %ld wants to get out of fast tracepoint jump pad (exit-jump-pad-bkpt)\n",
3062 /* Postpone any pending signal. It was enqueued above. */
3065 else if (fast_tp_collecting
== 2)
3069 lwp %ld wants to get out of fast tracepoint jump pad single-stepping\n",
3072 if (can_hardware_single_step ())
3075 fatal ("moving out of jump pad single-stepping"
3076 " not implemented on this target");
3078 /* Postpone any pending signal. It was enqueued above. */
3082 /* If we have while-stepping actions in this thread set it stepping.
3083 If we have a signal to deliver, it may or may not be set to
3084 SIG_IGN, we don't know. Assume so, and allow collecting
3085 while-stepping into a signal handler. A possible smart thing to
3086 do would be to set an internal breakpoint at the signal return
3087 address, continue, and carry on catching this while-stepping
3088 action only when that breakpoint is hit. A future
3090 if (get_lwp_thread (lwp
)->while_stepping
!= NULL
3091 && can_hardware_single_step ())
3095 "lwp %ld has a while-stepping action -> forcing step.\n",
3100 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
3102 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
3103 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
3104 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
3107 /* If we have pending signals, consume one unless we are trying to
3108 reinsert a breakpoint or we're trying to finish a fast tracepoint
3110 if (lwp
->pending_signals
!= NULL
3111 && lwp
->bp_reinsert
== 0
3112 && fast_tp_collecting
== 0)
3114 struct pending_signals
**p_sig
;
3116 p_sig
= &lwp
->pending_signals
;
3117 while ((*p_sig
)->prev
!= NULL
)
3118 p_sig
= &(*p_sig
)->prev
;
3120 signal
= (*p_sig
)->signal
;
3121 if ((*p_sig
)->info
.si_signo
!= 0)
3122 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
3128 if (the_low_target
.prepare_to_resume
!= NULL
)
3129 the_low_target
.prepare_to_resume (lwp
);
3131 regcache_invalidate_one ((struct inferior_list_entry
*)
3132 get_lwp_thread (lwp
));
3135 lwp
->stopped_by_watchpoint
= 0;
3136 lwp
->stepping
= step
;
3137 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0,
3138 /* Coerce to a uintptr_t first to avoid potential gcc warning
3139 of coercing an 8 byte integer to a 4 byte pointer. */
3140 (PTRACE_ARG4_TYPE
) (uintptr_t) signal
);
3142 current_inferior
= saved_inferior
;
3145 /* ESRCH from ptrace either means that the thread was already
3146 running (an error) or that it is gone (a race condition). If
3147 it's gone, we will get a notification the next time we wait,
3148 so we can ignore the error. We could differentiate these
3149 two, but it's tricky without waiting; the thread still exists
3150 as a zombie, so sending it signal 0 would succeed. So just
3155 perror_with_name ("ptrace");
3159 struct thread_resume_array
3161 struct thread_resume
*resume
;
3165 /* This function is called once per thread. We look up the thread
3166 in RESUME_PTR, and mark the thread with a pointer to the appropriate
3169 This algorithm is O(threads * resume elements), but resume elements
3170 is small (and will remain small at least until GDB supports thread
3173 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3175 struct lwp_info
*lwp
;
3176 struct thread_info
*thread
;
3178 struct thread_resume_array
*r
;
3180 thread
= (struct thread_info
*) entry
;
3181 lwp
= get_thread_lwp (thread
);
3184 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3186 ptid_t ptid
= r
->resume
[ndx
].thread
;
3187 if (ptid_equal (ptid
, minus_one_ptid
)
3188 || ptid_equal (ptid
, entry
->id
)
3189 || (ptid_is_pid (ptid
)
3190 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
3191 || (ptid_get_lwp (ptid
) == -1
3192 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
3194 if (r
->resume
[ndx
].kind
== resume_stop
3195 && thread
->last_resume_kind
== resume_stop
)
3198 fprintf (stderr
, "already %s LWP %ld at GDB's request\n",
3199 thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
3207 lwp
->resume
= &r
->resume
[ndx
];
3208 thread
->last_resume_kind
= lwp
->resume
->kind
;
3210 /* If we had a deferred signal to report, dequeue one now.
3211 This can happen if LWP gets more than one signal while
3212 trying to get out of a jump pad. */
3214 && !lwp
->status_pending_p
3215 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3217 lwp
->status_pending_p
= 1;
3221 "Dequeueing deferred signal %d for LWP %ld, "
3222 "leaving status pending.\n",
3223 WSTOPSIG (lwp
->status_pending
), lwpid_of (lwp
));
3230 /* No resume action for this thread. */
3237 /* Set *FLAG_P if this lwp has an interesting status pending. */
3239 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3241 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3243 /* LWPs which will not be resumed are not interesting, because
3244 we might not wait for them next time through linux_wait. */
3245 if (lwp
->resume
== NULL
)
3248 if (lwp
->status_pending_p
)
3249 * (int *) flag_p
= 1;
3254 /* Return 1 if this lwp that GDB wants running is stopped at an
3255 internal breakpoint that we need to step over. It assumes that any
3256 required STOP_PC adjustment has already been propagated to the
3257 inferior's regcache. */
3260 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3262 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3263 struct thread_info
*thread
;
3264 struct thread_info
*saved_inferior
;
3267 /* LWPs which will not be resumed are not interesting, because we
3268 might not wait for them next time through linux_wait. */
3274 "Need step over [LWP %ld]? Ignoring, not stopped\n",
3279 thread
= get_lwp_thread (lwp
);
3281 if (thread
->last_resume_kind
== resume_stop
)
3285 "Need step over [LWP %ld]? Ignoring, should remain stopped\n",
3290 gdb_assert (lwp
->suspended
>= 0);
3296 "Need step over [LWP %ld]? Ignoring, suspended\n",
3301 if (!lwp
->need_step_over
)
3305 "Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
3308 if (lwp
->status_pending_p
)
3312 "Need step over [LWP %ld]? Ignoring, has pending status.\n",
3317 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3321 /* If the PC has changed since we stopped, then don't do anything,
3322 and let the breakpoint/tracepoint be hit. This happens if, for
3323 instance, GDB handled the decr_pc_after_break subtraction itself,
3324 GDB is OOL stepping this thread, or the user has issued a "jump"
3325 command, or poked thread's registers herself. */
3326 if (pc
!= lwp
->stop_pc
)
3330 "Need step over [LWP %ld]? Cancelling, PC was changed. "
3331 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3332 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
3334 lwp
->need_step_over
= 0;
3338 saved_inferior
= current_inferior
;
3339 current_inferior
= thread
;
3341 /* We can only step over breakpoints we know about. */
3342 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3344 /* Don't step over a breakpoint that GDB expects to hit
3345 though. If the condition is being evaluated on the target's side
3346 and it evaluate to false, step over this breakpoint as well. */
3347 if (gdb_breakpoint_here (pc
)
3348 && gdb_condition_true_at_breakpoint (pc
))
3352 "Need step over [LWP %ld]? yes, but found"
3353 " GDB breakpoint at 0x%s; skipping step over\n",
3354 lwpid_of (lwp
), paddress (pc
));
3356 current_inferior
= saved_inferior
;
3363 "Need step over [LWP %ld]? yes, "
3364 "found breakpoint at 0x%s\n",
3365 lwpid_of (lwp
), paddress (pc
));
3367 /* We've found an lwp that needs stepping over --- return 1 so
3368 that find_inferior stops looking. */
3369 current_inferior
= saved_inferior
;
3371 /* If the step over is cancelled, this is set again. */
3372 lwp
->need_step_over
= 0;
3377 current_inferior
= saved_inferior
;
3381 "Need step over [LWP %ld]? No, no breakpoint found at 0x%s\n",
3382 lwpid_of (lwp
), paddress (pc
));
3387 /* Start a step-over operation on LWP. When LWP stopped at a
3388 breakpoint, to make progress, we need to remove the breakpoint out
3389 of the way. If we let other threads run while we do that, they may
3390 pass by the breakpoint location and miss hitting it. To avoid
3391 that, a step-over momentarily stops all threads while LWP is
3392 single-stepped while the breakpoint is temporarily uninserted from
3393 the inferior. When the single-step finishes, we reinsert the
3394 breakpoint, and let all threads that are supposed to be running,
3397 On targets that don't support hardware single-step, we don't
3398 currently support full software single-stepping. Instead, we only
3399 support stepping over the thread event breakpoint, by asking the
3400 low target where to place a reinsert breakpoint. Since this
3401 routine assumes the breakpoint being stepped over is a thread event
3402 breakpoint, it usually assumes the return address of the current
3403 function is a good enough place to set the reinsert breakpoint. */
3406 start_step_over (struct lwp_info
*lwp
)
3408 struct thread_info
*saved_inferior
;
3414 "Starting step-over on LWP %ld. Stopping all threads\n",
3417 stop_all_lwps (1, lwp
);
3418 gdb_assert (lwp
->suspended
== 0);
3421 fprintf (stderr
, "Done stopping all threads for step-over.\n");
3423 /* Note, we should always reach here with an already adjusted PC,
3424 either by GDB (if we're resuming due to GDB's request), or by our
3425 caller, if we just finished handling an internal breakpoint GDB
3426 shouldn't care about. */
3429 saved_inferior
= current_inferior
;
3430 current_inferior
= get_lwp_thread (lwp
);
3432 lwp
->bp_reinsert
= pc
;
3433 uninsert_breakpoints_at (pc
);
3434 uninsert_fast_tracepoint_jumps_at (pc
);
3436 if (can_hardware_single_step ())
3442 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3443 set_reinsert_breakpoint (raddr
);
3447 current_inferior
= saved_inferior
;
3449 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3451 /* Require next event from this LWP. */
3452 step_over_bkpt
= lwp
->head
.id
;
3456 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3457 start_step_over, if still there, and delete any reinsert
3458 breakpoints we've set, on non hardware single-step targets. */
3461 finish_step_over (struct lwp_info
*lwp
)
3463 if (lwp
->bp_reinsert
!= 0)
3466 fprintf (stderr
, "Finished step over.\n");
3468 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3469 may be no breakpoint to reinsert there by now. */
3470 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3471 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3473 lwp
->bp_reinsert
= 0;
3475 /* Delete any software-single-step reinsert breakpoints. No
3476 longer needed. We don't have to worry about other threads
3477 hitting this trap, and later not being able to explain it,
3478 because we were stepping over a breakpoint, and we hold all
3479 threads but LWP stopped while doing that. */
3480 if (!can_hardware_single_step ())
3481 delete_reinsert_breakpoints ();
3483 step_over_bkpt
= null_ptid
;
3490 /* This function is called once per thread. We check the thread's resume
3491 request, which will tell us whether to resume, step, or leave the thread
3492 stopped; and what signal, if any, it should be sent.
3494 For threads which we aren't explicitly told otherwise, we preserve
3495 the stepping flag; this is used for stepping over gdbserver-placed
3498 If pending_flags was set in any thread, we queue any needed
3499 signals, since we won't actually resume. We already have a pending
3500 event to report, so we don't need to preserve any step requests;
3501 they should be re-issued if necessary. */
3504 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3506 struct lwp_info
*lwp
;
3507 struct thread_info
*thread
;
3509 int leave_all_stopped
= * (int *) arg
;
3512 thread
= (struct thread_info
*) entry
;
3513 lwp
= get_thread_lwp (thread
);
3515 if (lwp
->resume
== NULL
)
3518 if (lwp
->resume
->kind
== resume_stop
)
3521 fprintf (stderr
, "resume_stop request for LWP %ld\n", lwpid_of (lwp
));
3526 fprintf (stderr
, "stopping LWP %ld\n", lwpid_of (lwp
));
3528 /* Stop the thread, and wait for the event asynchronously,
3529 through the event loop. */
3535 fprintf (stderr
, "already stopped LWP %ld\n",
3538 /* The LWP may have been stopped in an internal event that
3539 was not meant to be notified back to GDB (e.g., gdbserver
3540 breakpoint), so we should be reporting a stop event in
3543 /* If the thread already has a pending SIGSTOP, this is a
3544 no-op. Otherwise, something later will presumably resume
3545 the thread and this will cause it to cancel any pending
3546 operation, due to last_resume_kind == resume_stop. If
3547 the thread already has a pending status to report, we
3548 will still report it the next time we wait - see
3549 status_pending_p_callback. */
3551 /* If we already have a pending signal to report, then
3552 there's no need to queue a SIGSTOP, as this means we're
3553 midway through moving the LWP out of the jumppad, and we
3554 will report the pending signal as soon as that is
3556 if (lwp
->pending_signals_to_report
== NULL
)
3560 /* For stop requests, we're done. */
3562 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3566 /* If this thread which is about to be resumed has a pending status,
3567 then don't resume any threads - we can just report the pending
3568 status. Make sure to queue any signals that would otherwise be
3569 sent. In all-stop mode, we do this decision based on if *any*
3570 thread has a pending status. If there's a thread that needs the
3571 step-over-breakpoint dance, then don't resume any other thread
3572 but that particular one. */
3573 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
3578 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
3580 step
= (lwp
->resume
->kind
== resume_step
);
3581 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
3586 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
3588 /* If we have a new signal, enqueue the signal. */
3589 if (lwp
->resume
->sig
!= 0)
3591 struct pending_signals
*p_sig
;
3592 p_sig
= xmalloc (sizeof (*p_sig
));
3593 p_sig
->prev
= lwp
->pending_signals
;
3594 p_sig
->signal
= lwp
->resume
->sig
;
3595 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3597 /* If this is the same signal we were previously stopped by,
3598 make sure to queue its siginfo. We can ignore the return
3599 value of ptrace; if it fails, we'll skip
3600 PTRACE_SETSIGINFO. */
3601 if (WIFSTOPPED (lwp
->last_status
)
3602 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
3603 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
3605 lwp
->pending_signals
= p_sig
;
3609 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3615 linux_resume (struct thread_resume
*resume_info
, size_t n
)
3617 struct thread_resume_array array
= { resume_info
, n
};
3618 struct lwp_info
*need_step_over
= NULL
;
3620 int leave_all_stopped
;
3622 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
3624 /* If there is a thread which would otherwise be resumed, which has
3625 a pending status, then don't resume any threads - we can just
3626 report the pending status. Make sure to queue any signals that
3627 would otherwise be sent. In non-stop mode, we'll apply this
3628 logic to each thread individually. We consume all pending events
3629 before considering to start a step-over (in all-stop). */
3632 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
3634 /* If there is a thread which would otherwise be resumed, which is
3635 stopped at a breakpoint that needs stepping over, then don't
3636 resume any threads - have it step over the breakpoint with all
3637 other threads stopped, then resume all threads again. Make sure
3638 to queue any signals that would otherwise be delivered or
3640 if (!any_pending
&& supports_breakpoints ())
3642 = (struct lwp_info
*) find_inferior (&all_lwps
,
3643 need_step_over_p
, NULL
);
3645 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
3649 if (need_step_over
!= NULL
)
3650 fprintf (stderr
, "Not resuming all, need step over\n");
3651 else if (any_pending
)
3653 "Not resuming, all-stop and found "
3654 "an LWP with pending status\n");
3656 fprintf (stderr
, "Resuming, no pending status or step over needed\n");
3659 /* Even if we're leaving threads stopped, queue all signals we'd
3660 otherwise deliver. */
3661 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
3664 start_step_over (need_step_over
);
3667 /* This function is called once per thread. We check the thread's
3668 last resume request, which will tell us whether to resume, step, or
3669 leave the thread stopped. Any signal the client requested to be
3670 delivered has already been enqueued at this point.
3672 If any thread that GDB wants running is stopped at an internal
3673 breakpoint that needs stepping over, we start a step-over operation
3674 on that particular thread, and leave all others stopped. */
3677 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3679 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3680 struct thread_info
*thread
;
3688 "proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
3693 fprintf (stderr
, " LWP %ld already running\n", lwpid_of (lwp
));
3697 thread
= get_lwp_thread (lwp
);
3699 if (thread
->last_resume_kind
== resume_stop
3700 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
3703 fprintf (stderr
, " client wants LWP to remain %ld stopped\n",
3708 if (lwp
->status_pending_p
)
3711 fprintf (stderr
, " LWP %ld has pending status, leaving stopped\n",
3716 gdb_assert (lwp
->suspended
>= 0);
3721 fprintf (stderr
, " LWP %ld is suspended\n", lwpid_of (lwp
));
3725 if (thread
->last_resume_kind
== resume_stop
3726 && lwp
->pending_signals_to_report
== NULL
3727 && lwp
->collecting_fast_tracepoint
== 0)
3729 /* We haven't reported this LWP as stopped yet (otherwise, the
3730 last_status.kind check above would catch it, and we wouldn't
3731 reach here. This LWP may have been momentarily paused by a
3732 stop_all_lwps call while handling for example, another LWP's
3733 step-over. In that case, the pending expected SIGSTOP signal
3734 that was queued at vCont;t handling time will have already
3735 been consumed by wait_for_sigstop, and so we need to requeue
3736 another one here. Note that if the LWP already has a SIGSTOP
3737 pending, this is a no-op. */
3741 "Client wants LWP %ld to stop. "
3742 "Making sure it has a SIGSTOP pending\n",
3748 step
= thread
->last_resume_kind
== resume_step
;
3749 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3754 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3756 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3762 gdb_assert (lwp
->suspended
>= 0);
3764 return proceed_one_lwp (entry
, except
);
3767 /* When we finish a step-over, set threads running again. If there's
3768 another thread that may need a step-over, now's the time to start
3769 it. Eventually, we'll move all threads past their breakpoints. */
3772 proceed_all_lwps (void)
3774 struct lwp_info
*need_step_over
;
3776 /* If there is a thread which would otherwise be resumed, which is
3777 stopped at a breakpoint that needs stepping over, then don't
3778 resume any threads - have it step over the breakpoint with all
3779 other threads stopped, then resume all threads again. */
3781 if (supports_breakpoints ())
3784 = (struct lwp_info
*) find_inferior (&all_lwps
,
3785 need_step_over_p
, NULL
);
3787 if (need_step_over
!= NULL
)
3790 fprintf (stderr
, "proceed_all_lwps: found "
3791 "thread %ld needing a step-over\n",
3792 lwpid_of (need_step_over
));
3794 start_step_over (need_step_over
);
3800 fprintf (stderr
, "Proceeding, no step-over needed\n");
3802 find_inferior (&all_lwps
, proceed_one_lwp
, NULL
);
3805 /* Stopped LWPs that the client wanted to be running, that don't have
3806 pending statuses, are set to run again, except for EXCEPT, if not
3807 NULL. This undoes a stop_all_lwps call. */
3810 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
3816 "unstopping all lwps, except=(LWP %ld)\n", lwpid_of (except
));
3819 "unstopping all lwps\n");
3823 find_inferior (&all_lwps
, unsuspend_and_proceed_one_lwp
, except
);
3825 find_inferior (&all_lwps
, proceed_one_lwp
, except
);
3829 #ifdef HAVE_LINUX_REGSETS
3831 #define use_linux_regsets 1
3834 regsets_fetch_inferior_registers (struct regcache
*regcache
)
3836 struct regset_info
*regset
;
3837 int saw_general_regs
= 0;
3841 regset
= target_regsets
;
3843 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3844 while (regset
->size
>= 0)
3849 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
3855 buf
= xmalloc (regset
->size
);
3857 nt_type
= regset
->nt_type
;
3861 iov
.iov_len
= regset
->size
;
3862 data
= (void *) &iov
;
3868 res
= ptrace (regset
->get_request
, pid
, nt_type
, data
);
3870 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
3876 /* If we get EIO on a regset, do not try it again for
3878 disabled_regsets
[regset
- target_regsets
] = 1;
3885 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
3890 else if (regset
->type
== GENERAL_REGS
)
3891 saw_general_regs
= 1;
3892 regset
->store_function (regcache
, buf
);
3896 if (saw_general_regs
)
3903 regsets_store_inferior_registers (struct regcache
*regcache
)
3905 struct regset_info
*regset
;
3906 int saw_general_regs
= 0;
3910 regset
= target_regsets
;
3912 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3913 while (regset
->size
>= 0)
3918 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
3924 buf
= xmalloc (regset
->size
);
3926 /* First fill the buffer with the current register set contents,
3927 in case there are any items in the kernel's regset that are
3928 not in gdbserver's regcache. */
3930 nt_type
= regset
->nt_type
;
3934 iov
.iov_len
= regset
->size
;
3935 data
= (void *) &iov
;
3941 res
= ptrace (regset
->get_request
, pid
, nt_type
, data
);
3943 res
= ptrace (regset
->get_request
, pid
, &iov
, data
);
3948 /* Then overlay our cached registers on that. */
3949 regset
->fill_function (regcache
, buf
);
3951 /* Only now do we write the register set. */
3953 res
= ptrace (regset
->set_request
, pid
, nt_type
, data
);
3955 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
3963 /* If we get EIO on a regset, do not try it again for
3965 disabled_regsets
[regset
- target_regsets
] = 1;
3969 else if (errno
== ESRCH
)
3971 /* At this point, ESRCH should mean the process is
3972 already gone, in which case we simply ignore attempts
3973 to change its registers. See also the related
3974 comment in linux_resume_one_lwp. */
3980 perror ("Warning: ptrace(regsets_store_inferior_registers)");
3983 else if (regset
->type
== GENERAL_REGS
)
3984 saw_general_regs
= 1;
3988 if (saw_general_regs
)
3994 #else /* !HAVE_LINUX_REGSETS */
3996 #define use_linux_regsets 0
3997 #define regsets_fetch_inferior_registers(regcache) 1
3998 #define regsets_store_inferior_registers(regcache) 1
4002 /* Return 1 if register REGNO is supported by one of the regset ptrace
4003 calls or 0 if it has to be transferred individually. */
4006 linux_register_in_regsets (int regno
)
4008 unsigned char mask
= 1 << (regno
% 8);
4009 size_t index
= regno
/ 8;
4011 return (use_linux_regsets
4012 && (the_low_target
.regset_bitmap
== NULL
4013 || (the_low_target
.regset_bitmap
[index
] & mask
) != 0));
4016 #ifdef HAVE_LINUX_USRREGS
4019 register_addr (int regnum
)
4023 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
4024 error ("Invalid register number %d.", regnum
);
4026 addr
= the_low_target
.regmap
[regnum
];
4031 /* Fetch one register. */
4033 fetch_register (struct regcache
*regcache
, int regno
)
4040 if (regno
>= the_low_target
.num_regs
)
4042 if ((*the_low_target
.cannot_fetch_register
) (regno
))
4045 regaddr
= register_addr (regno
);
4049 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4050 & -sizeof (PTRACE_XFER_TYPE
));
4051 buf
= alloca (size
);
4053 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4054 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4057 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
4058 ptrace (PTRACE_PEEKUSER
, pid
,
4059 /* Coerce to a uintptr_t first to avoid potential gcc warning
4060 of coercing an 8 byte integer to a 4 byte pointer. */
4061 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
, 0);
4062 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4064 error ("reading register %d: %s", regno
, strerror (errno
));
4067 if (the_low_target
.supply_ptrace_register
)
4068 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
4070 supply_register (regcache
, regno
, buf
);
4073 /* Store one register. */
4075 store_register (struct regcache
*regcache
, int regno
)
4082 if (regno
>= the_low_target
.num_regs
)
4084 if ((*the_low_target
.cannot_store_register
) (regno
))
4087 regaddr
= register_addr (regno
);
4091 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4092 & -sizeof (PTRACE_XFER_TYPE
));
4093 buf
= alloca (size
);
4094 memset (buf
, 0, size
);
4096 if (the_low_target
.collect_ptrace_register
)
4097 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
4099 collect_register (regcache
, regno
, buf
);
4101 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4102 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4105 ptrace (PTRACE_POKEUSER
, pid
,
4106 /* Coerce to a uintptr_t first to avoid potential gcc warning
4107 about coercing an 8 byte integer to a 4 byte pointer. */
4108 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
,
4109 (PTRACE_ARG4_TYPE
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
4112 /* At this point, ESRCH should mean the process is
4113 already gone, in which case we simply ignore attempts
4114 to change its registers. See also the related
4115 comment in linux_resume_one_lwp. */
4119 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
4120 error ("writing register %d: %s", regno
, strerror (errno
));
4122 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4126 /* Fetch all registers, or just one, from the child process.
4127 If REGNO is -1, do this for all registers, skipping any that are
4128 assumed to have been retrieved by regsets_fetch_inferior_registers,
4129 unless ALL is non-zero.
4130 Otherwise, REGNO specifies which register (so we can save time). */
4132 usr_fetch_inferior_registers (struct regcache
*regcache
, int regno
, int all
)
4136 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4137 if (all
|| !linux_register_in_regsets (regno
))
4138 fetch_register (regcache
, regno
);
4141 fetch_register (regcache
, regno
);
4144 /* Store our register values back into the inferior.
4145 If REGNO is -1, do this for all registers, skipping any that are
4146 assumed to have been saved by regsets_store_inferior_registers,
4147 unless ALL is non-zero.
4148 Otherwise, REGNO specifies which register (so we can save time). */
4150 usr_store_inferior_registers (struct regcache
*regcache
, int regno
, int all
)
4154 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4155 if (all
|| !linux_register_in_regsets (regno
))
4156 store_register (regcache
, regno
);
4159 store_register (regcache
, regno
);
4162 #else /* !HAVE_LINUX_USRREGS */
4164 #define usr_fetch_inferior_registers(regcache, regno, all) do {} while (0)
4165 #define usr_store_inferior_registers(regcache, regno, all) do {} while (0)
4171 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4178 all
= regsets_fetch_inferior_registers (regcache
);
4179 usr_fetch_inferior_registers (regcache
, regno
, all
);
4183 use_regsets
= linux_register_in_regsets (regno
);
4185 all
= regsets_fetch_inferior_registers (regcache
);
4186 if (!use_regsets
|| all
)
4187 usr_fetch_inferior_registers (regcache
, regno
, 1);
4192 linux_store_registers (struct regcache
*regcache
, int regno
)
4199 all
= regsets_store_inferior_registers (regcache
);
4200 usr_store_inferior_registers (regcache
, regno
, all
);
4204 use_regsets
= linux_register_in_regsets (regno
);
4206 all
= regsets_store_inferior_registers (regcache
);
4207 if (!use_regsets
|| all
)
4208 usr_store_inferior_registers (regcache
, regno
, 1);
4213 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4214 to debugger memory starting at MYADDR. */
4217 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4220 /* Round starting address down to longword boundary. */
4221 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4222 /* Round ending address up; get number of longwords that makes. */
4224 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4225 / sizeof (PTRACE_XFER_TYPE
);
4226 /* Allocate buffer of that many longwords. */
4227 register PTRACE_XFER_TYPE
*buffer
4228 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4231 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4233 /* Try using /proc. Don't bother for one word. */
4234 if (len
>= 3 * sizeof (long))
4236 /* We could keep this file open and cache it - possibly one per
4237 thread. That requires some juggling, but is even faster. */
4238 sprintf (filename
, "/proc/%d/mem", pid
);
4239 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4243 /* If pread64 is available, use it. It's faster if the kernel
4244 supports it (only one syscall), and it's 64-bit safe even on
4245 32-bit platforms (for instance, SPARC debugging a SPARC64
4248 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
4250 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, myaddr
, len
) != len
)
4262 /* Read all the longwords */
4263 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4266 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4267 about coercing an 8 byte integer to a 4 byte pointer. */
4268 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4269 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4274 /* Copy appropriate bytes out of the buffer. */
4276 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4282 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4283 memory at MEMADDR. On failure (cannot write to the inferior)
4284 returns the value of errno. */
4287 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4290 /* Round starting address down to longword boundary. */
4291 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4292 /* Round ending address up; get number of longwords that makes. */
4294 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4295 / sizeof (PTRACE_XFER_TYPE
);
4297 /* Allocate buffer of that many longwords. */
4298 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4299 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4301 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4305 /* Dump up to four bytes. */
4306 unsigned int val
= * (unsigned int *) myaddr
;
4312 val
= val
& 0xffffff;
4313 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4314 val
, (long)memaddr
);
4317 /* Fill start and end extra bytes of buffer with existing memory data. */
4320 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4321 about coercing an 8 byte integer to a 4 byte pointer. */
4322 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4323 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4331 = ptrace (PTRACE_PEEKTEXT
, pid
,
4332 /* Coerce to a uintptr_t first to avoid potential gcc warning
4333 about coercing an 8 byte integer to a 4 byte pointer. */
4334 (PTRACE_ARG3_TYPE
) (uintptr_t) (addr
+ (count
- 1)
4335 * sizeof (PTRACE_XFER_TYPE
)),
4341 /* Copy data to be written over corresponding part of buffer. */
4343 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4346 /* Write the entire buffer. */
4348 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4351 ptrace (PTRACE_POKETEXT
, pid
,
4352 /* Coerce to a uintptr_t first to avoid potential gcc warning
4353 about coercing an 8 byte integer to a 4 byte pointer. */
4354 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
4355 (PTRACE_ARG4_TYPE
) buffer
[i
]);
4363 /* Non-zero if the kernel supports PTRACE_O_TRACEFORK. */
4364 static int linux_supports_tracefork_flag
;
4367 linux_enable_event_reporting (int pid
)
4369 if (!linux_supports_tracefork_flag
)
4372 ptrace (PTRACE_SETOPTIONS
, pid
, 0, (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
4375 /* Helper functions for linux_test_for_tracefork, called via clone (). */
4378 linux_tracefork_grandchild (void *arg
)
4383 #define STACK_SIZE 4096
4386 linux_tracefork_child (void *arg
)
4388 ptrace (PTRACE_TRACEME
, 0, 0, 0);
4389 kill (getpid (), SIGSTOP
);
4391 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4394 linux_tracefork_grandchild (NULL
);
4396 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4399 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
4400 CLONE_VM
| SIGCHLD
, NULL
);
4402 clone (linux_tracefork_grandchild
, (char *) arg
+ STACK_SIZE
,
4403 CLONE_VM
| SIGCHLD
, NULL
);
4406 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4411 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
4412 sure that we can enable the option, and that it had the desired
4416 linux_test_for_tracefork (void)
4418 int child_pid
, ret
, status
;
4420 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4421 char *stack
= xmalloc (STACK_SIZE
* 4);
4422 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4424 linux_supports_tracefork_flag
= 0;
4426 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4428 child_pid
= fork ();
4430 linux_tracefork_child (NULL
);
4432 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4434 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
4436 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
4437 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4438 #else /* !__ia64__ */
4439 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
4440 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4441 #endif /* !__ia64__ */
4443 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4445 if (child_pid
== -1)
4446 perror_with_name ("clone");
4448 ret
= my_waitpid (child_pid
, &status
, 0);
4450 perror_with_name ("waitpid");
4451 else if (ret
!= child_pid
)
4452 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
4453 if (! WIFSTOPPED (status
))
4454 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
4456 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
4457 (PTRACE_ARG4_TYPE
) PTRACE_O_TRACEFORK
);
4460 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4463 warning ("linux_test_for_tracefork: failed to kill child");
4467 ret
= my_waitpid (child_pid
, &status
, 0);
4468 if (ret
!= child_pid
)
4469 warning ("linux_test_for_tracefork: failed to wait for killed child");
4470 else if (!WIFSIGNALED (status
))
4471 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
4472 "killed child", status
);
4477 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
4479 warning ("linux_test_for_tracefork: failed to resume child");
4481 ret
= my_waitpid (child_pid
, &status
, 0);
4483 if (ret
== child_pid
&& WIFSTOPPED (status
)
4484 && status
>> 16 == PTRACE_EVENT_FORK
)
4487 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
4488 if (ret
== 0 && second_pid
!= 0)
4492 linux_supports_tracefork_flag
= 1;
4493 my_waitpid (second_pid
, &second_status
, 0);
4494 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
4496 warning ("linux_test_for_tracefork: failed to kill second child");
4497 my_waitpid (second_pid
, &status
, 0);
4501 warning ("linux_test_for_tracefork: unexpected result from waitpid "
4502 "(%d, status 0x%x)", ret
, status
);
4506 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4508 warning ("linux_test_for_tracefork: failed to kill child");
4509 my_waitpid (child_pid
, &status
, 0);
4511 while (WIFSTOPPED (status
));
4513 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4515 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4520 linux_look_up_symbols (void)
4522 #ifdef USE_THREAD_DB
4523 struct process_info
*proc
= current_process ();
4525 if (proc
->private->thread_db
!= NULL
)
4528 /* If the kernel supports tracing forks then it also supports tracing
4529 clones, and then we don't need to use the magic thread event breakpoint
4530 to learn about threads. */
4531 thread_db_init (!linux_supports_tracefork_flag
);
4536 linux_request_interrupt (void)
4538 extern unsigned long signal_pid
;
4540 if (!ptid_equal (cont_thread
, null_ptid
)
4541 && !ptid_equal (cont_thread
, minus_one_ptid
))
4543 struct lwp_info
*lwp
;
4546 lwp
= get_thread_lwp (current_inferior
);
4547 lwpid
= lwpid_of (lwp
);
4548 kill_lwp (lwpid
, SIGINT
);
4551 kill_lwp (signal_pid
, SIGINT
);
4554 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4555 to debugger memory starting at MYADDR. */
4558 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4560 char filename
[PATH_MAX
];
4562 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4564 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4566 fd
= open (filename
, O_RDONLY
);
4570 if (offset
!= (CORE_ADDR
) 0
4571 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4574 n
= read (fd
, myaddr
, len
);
4581 /* These breakpoint and watchpoint related wrapper functions simply
4582 pass on the function call if the target has registered a
4583 corresponding function. */
4586 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
4588 if (the_low_target
.insert_point
!= NULL
)
4589 return the_low_target
.insert_point (type
, addr
, len
);
4591 /* Unsupported (see target.h). */
4596 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
4598 if (the_low_target
.remove_point
!= NULL
)
4599 return the_low_target
.remove_point (type
, addr
, len
);
4601 /* Unsupported (see target.h). */
4606 linux_stopped_by_watchpoint (void)
4608 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4610 return lwp
->stopped_by_watchpoint
;
4614 linux_stopped_data_address (void)
4616 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4618 return lwp
->stopped_data_address
;
4621 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4622 #if defined(__mcoldfire__)
4623 /* These should really be defined in the kernel's ptrace.h header. */
4624 #define PT_TEXT_ADDR 49*4
4625 #define PT_DATA_ADDR 50*4
4626 #define PT_TEXT_END_ADDR 51*4
4628 #define PT_TEXT_ADDR 220
4629 #define PT_TEXT_END_ADDR 224
4630 #define PT_DATA_ADDR 228
4631 #elif defined(__TMS320C6X__)
4632 #define PT_TEXT_ADDR (0x10000*4)
4633 #define PT_DATA_ADDR (0x10004*4)
4634 #define PT_TEXT_END_ADDR (0x10008*4)
4637 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4638 to tell gdb about. */
4641 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
4643 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
4644 unsigned long text
, text_end
, data
;
4645 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4649 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
4650 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
4651 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
4655 /* Both text and data offsets produced at compile-time (and so
4656 used by gdb) are relative to the beginning of the program,
4657 with the data segment immediately following the text segment.
4658 However, the actual runtime layout in memory may put the data
4659 somewhere else, so when we send gdb a data base-address, we
4660 use the real data base address and subtract the compile-time
4661 data base-address from it (which is just the length of the
4662 text segment). BSS immediately follows data in both
4665 *data_p
= data
- (text_end
- text
);
4675 linux_qxfer_osdata (const char *annex
,
4676 unsigned char *readbuf
, unsigned const char *writebuf
,
4677 CORE_ADDR offset
, int len
)
4679 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
4682 /* Convert a native/host siginfo object, into/from the siginfo in the
4683 layout of the inferiors' architecture. */
4686 siginfo_fixup (struct siginfo
*siginfo
, void *inf_siginfo
, int direction
)
4690 if (the_low_target
.siginfo_fixup
!= NULL
)
4691 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4693 /* If there was no callback, or the callback didn't do anything,
4694 then just do a straight memcpy. */
4698 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
4700 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
4705 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
4706 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
4709 struct siginfo siginfo
;
4710 char inf_siginfo
[sizeof (struct siginfo
)];
4712 if (current_inferior
== NULL
)
4715 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4718 fprintf (stderr
, "%s siginfo for lwp %d.\n",
4719 readbuf
!= NULL
? "Reading" : "Writing",
4722 if (offset
>= sizeof (siginfo
))
4725 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
4728 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4729 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4730 inferior with a 64-bit GDBSERVER should look the same as debugging it
4731 with a 32-bit GDBSERVER, we need to convert it. */
4732 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4734 if (offset
+ len
> sizeof (siginfo
))
4735 len
= sizeof (siginfo
) - offset
;
4737 if (readbuf
!= NULL
)
4738 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4741 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4743 /* Convert back to ptrace layout before flushing it out. */
4744 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4746 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
4753 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4754 so we notice when children change state; as the handler for the
4755 sigsuspend in my_waitpid. */
4758 sigchld_handler (int signo
)
4760 int old_errno
= errno
;
4766 /* fprintf is not async-signal-safe, so call write
4768 if (write (2, "sigchld_handler\n",
4769 sizeof ("sigchld_handler\n") - 1) < 0)
4770 break; /* just ignore */
4774 if (target_is_async_p ())
4775 async_file_mark (); /* trigger a linux_wait */
4781 linux_supports_non_stop (void)
4787 linux_async (int enable
)
4789 int previous
= (linux_event_pipe
[0] != -1);
4792 fprintf (stderr
, "linux_async (%d), previous=%d\n",
4795 if (previous
!= enable
)
4798 sigemptyset (&mask
);
4799 sigaddset (&mask
, SIGCHLD
);
4801 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
4805 if (pipe (linux_event_pipe
) == -1)
4806 fatal ("creating event pipe failed.");
4808 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
4809 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
4811 /* Register the event loop handler. */
4812 add_file_handler (linux_event_pipe
[0],
4813 handle_target_event
, NULL
);
4815 /* Always trigger a linux_wait. */
4820 delete_file_handler (linux_event_pipe
[0]);
4822 close (linux_event_pipe
[0]);
4823 close (linux_event_pipe
[1]);
4824 linux_event_pipe
[0] = -1;
4825 linux_event_pipe
[1] = -1;
4828 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
4835 linux_start_non_stop (int nonstop
)
4837 /* Register or unregister from event-loop accordingly. */
4838 linux_async (nonstop
);
4843 linux_supports_multi_process (void)
4849 linux_supports_disable_randomization (void)
4851 #ifdef HAVE_PERSONALITY
4859 linux_supports_agent (void)
4864 /* Enumerate spufs IDs for process PID. */
4866 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
4872 struct dirent
*entry
;
4874 sprintf (path
, "/proc/%ld/fd", pid
);
4875 dir
= opendir (path
);
4880 while ((entry
= readdir (dir
)) != NULL
)
4886 fd
= atoi (entry
->d_name
);
4890 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
4891 if (stat (path
, &st
) != 0)
4893 if (!S_ISDIR (st
.st_mode
))
4896 if (statfs (path
, &stfs
) != 0)
4898 if (stfs
.f_type
!= SPUFS_MAGIC
)
4901 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
4903 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
4913 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
4914 object type, using the /proc file system. */
4916 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
4917 unsigned const char *writebuf
,
4918 CORE_ADDR offset
, int len
)
4920 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
4925 if (!writebuf
&& !readbuf
)
4933 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
4936 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
4937 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
4942 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4949 ret
= write (fd
, writebuf
, (size_t) len
);
4951 ret
= read (fd
, readbuf
, (size_t) len
);
4957 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
4958 struct target_loadseg
4960 /* Core address to which the segment is mapped. */
4962 /* VMA recorded in the program header. */
4964 /* Size of this segment in memory. */
4968 # if defined PT_GETDSBT
4969 struct target_loadmap
4971 /* Protocol version number, must be zero. */
4973 /* Pointer to the DSBT table, its size, and the DSBT index. */
4974 unsigned *dsbt_table
;
4975 unsigned dsbt_size
, dsbt_index
;
4976 /* Number of segments in this map. */
4978 /* The actual memory map. */
4979 struct target_loadseg segs
[/*nsegs*/];
4981 # define LINUX_LOADMAP PT_GETDSBT
4982 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
4983 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
4985 struct target_loadmap
4987 /* Protocol version number, must be zero. */
4989 /* Number of segments in this map. */
4991 /* The actual memory map. */
4992 struct target_loadseg segs
[/*nsegs*/];
4994 # define LINUX_LOADMAP PTRACE_GETFDPIC
4995 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
4996 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5000 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
5001 unsigned char *myaddr
, unsigned int len
)
5003 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
5005 struct target_loadmap
*data
= NULL
;
5006 unsigned int actual_length
, copy_length
;
5008 if (strcmp (annex
, "exec") == 0)
5009 addr
= (int) LINUX_LOADMAP_EXEC
;
5010 else if (strcmp (annex
, "interp") == 0)
5011 addr
= (int) LINUX_LOADMAP_INTERP
;
5015 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
5021 actual_length
= sizeof (struct target_loadmap
)
5022 + sizeof (struct target_loadseg
) * data
->nsegs
;
5024 if (offset
< 0 || offset
> actual_length
)
5027 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
5028 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
5032 # define linux_read_loadmap NULL
5033 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5036 linux_process_qsupported (const char *query
)
5038 if (the_low_target
.process_qsupported
!= NULL
)
5039 the_low_target
.process_qsupported (query
);
5043 linux_supports_tracepoints (void)
5045 if (*the_low_target
.supports_tracepoints
== NULL
)
5048 return (*the_low_target
.supports_tracepoints
) ();
5052 linux_read_pc (struct regcache
*regcache
)
5054 if (the_low_target
.get_pc
== NULL
)
5057 return (*the_low_target
.get_pc
) (regcache
);
5061 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
5063 gdb_assert (the_low_target
.set_pc
!= NULL
);
5065 (*the_low_target
.set_pc
) (regcache
, pc
);
5069 linux_thread_stopped (struct thread_info
*thread
)
5071 return get_thread_lwp (thread
)->stopped
;
5074 /* This exposes stop-all-threads functionality to other modules. */
5077 linux_pause_all (int freeze
)
5079 stop_all_lwps (freeze
, NULL
);
5082 /* This exposes unstop-all-threads functionality to other gdbserver
5086 linux_unpause_all (int unfreeze
)
5088 unstop_all_lwps (unfreeze
, NULL
);
5092 linux_prepare_to_access_memory (void)
5094 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5097 linux_pause_all (1);
5102 linux_done_accessing_memory (void)
5104 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5107 linux_unpause_all (1);
5111 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5112 CORE_ADDR collector
,
5115 CORE_ADDR
*jump_entry
,
5116 CORE_ADDR
*trampoline
,
5117 ULONGEST
*trampoline_size
,
5118 unsigned char *jjump_pad_insn
,
5119 ULONGEST
*jjump_pad_insn_size
,
5120 CORE_ADDR
*adjusted_insn_addr
,
5121 CORE_ADDR
*adjusted_insn_addr_end
,
5124 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5125 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5126 jump_entry
, trampoline
, trampoline_size
,
5127 jjump_pad_insn
, jjump_pad_insn_size
,
5128 adjusted_insn_addr
, adjusted_insn_addr_end
,
5132 static struct emit_ops
*
5133 linux_emit_ops (void)
5135 if (the_low_target
.emit_ops
!= NULL
)
5136 return (*the_low_target
.emit_ops
) ();
5142 linux_get_min_fast_tracepoint_insn_len (void)
5144 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5147 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5150 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5151 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5153 char filename
[PATH_MAX
];
5155 const int auxv_size
= is_elf64
5156 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5157 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5159 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5161 fd
= open (filename
, O_RDONLY
);
5167 while (read (fd
, buf
, auxv_size
) == auxv_size
5168 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5172 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5174 switch (aux
->a_type
)
5177 *phdr_memaddr
= aux
->a_un
.a_val
;
5180 *num_phdr
= aux
->a_un
.a_val
;
5186 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5188 switch (aux
->a_type
)
5191 *phdr_memaddr
= aux
->a_un
.a_val
;
5194 *num_phdr
= aux
->a_un
.a_val
;
5202 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5204 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5205 "phdr_memaddr = %ld, phdr_num = %d",
5206 (long) *phdr_memaddr
, *num_phdr
);
5213 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5216 get_dynamic (const int pid
, const int is_elf64
)
5218 CORE_ADDR phdr_memaddr
, relocation
;
5220 unsigned char *phdr_buf
;
5221 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5223 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5226 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5227 phdr_buf
= alloca (num_phdr
* phdr_size
);
5229 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5232 /* Compute relocation: it is expected to be 0 for "regular" executables,
5233 non-zero for PIE ones. */
5235 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5238 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5240 if (p
->p_type
== PT_PHDR
)
5241 relocation
= phdr_memaddr
- p
->p_vaddr
;
5245 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5247 if (p
->p_type
== PT_PHDR
)
5248 relocation
= phdr_memaddr
- p
->p_vaddr
;
5251 if (relocation
== -1)
5253 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5254 any real world executables, including PIE executables, have always
5255 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5256 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5257 or present DT_DEBUG anyway (fpc binaries are statically linked).
5259 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5261 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5266 for (i
= 0; i
< num_phdr
; i
++)
5270 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5272 if (p
->p_type
== PT_DYNAMIC
)
5273 return p
->p_vaddr
+ relocation
;
5277 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5279 if (p
->p_type
== PT_DYNAMIC
)
5280 return p
->p_vaddr
+ relocation
;
5287 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5288 can be 0 if the inferior does not yet have the library list initialized. */
5291 get_r_debug (const int pid
, const int is_elf64
)
5293 CORE_ADDR dynamic_memaddr
;
5294 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5295 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5297 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5298 if (dynamic_memaddr
== 0)
5299 return (CORE_ADDR
) -1;
5301 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5305 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5307 if (dyn
->d_tag
== DT_DEBUG
)
5308 return dyn
->d_un
.d_val
;
5310 if (dyn
->d_tag
== DT_NULL
)
5315 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5317 if (dyn
->d_tag
== DT_DEBUG
)
5318 return dyn
->d_un
.d_val
;
5320 if (dyn
->d_tag
== DT_NULL
)
5324 dynamic_memaddr
+= dyn_size
;
5327 return (CORE_ADDR
) -1;
5330 /* Read one pointer from MEMADDR in the inferior. */
5333 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5336 return linux_read_memory (memaddr
, (unsigned char *) ptr
, ptr_size
);
5339 struct link_map_offsets
5341 /* Offset and size of r_debug.r_version. */
5342 int r_version_offset
;
5344 /* Offset and size of r_debug.r_map. */
5347 /* Offset to l_addr field in struct link_map. */
5350 /* Offset to l_name field in struct link_map. */
5353 /* Offset to l_ld field in struct link_map. */
5356 /* Offset to l_next field in struct link_map. */
5359 /* Offset to l_prev field in struct link_map. */
5363 /* Construct qXfer:libraries:read reply. */
5366 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5367 unsigned const char *writebuf
,
5368 CORE_ADDR offset
, int len
)
5371 unsigned document_len
;
5372 struct process_info_private
*const priv
= current_process ()->private;
5373 char filename
[PATH_MAX
];
5376 static const struct link_map_offsets lmo_32bit_offsets
=
5378 0, /* r_version offset. */
5379 4, /* r_debug.r_map offset. */
5380 0, /* l_addr offset in link_map. */
5381 4, /* l_name offset in link_map. */
5382 8, /* l_ld offset in link_map. */
5383 12, /* l_next offset in link_map. */
5384 16 /* l_prev offset in link_map. */
5387 static const struct link_map_offsets lmo_64bit_offsets
=
5389 0, /* r_version offset. */
5390 8, /* r_debug.r_map offset. */
5391 0, /* l_addr offset in link_map. */
5392 8, /* l_name offset in link_map. */
5393 16, /* l_ld offset in link_map. */
5394 24, /* l_next offset in link_map. */
5395 32 /* l_prev offset in link_map. */
5397 const struct link_map_offsets
*lmo
;
5399 if (writebuf
!= NULL
)
5401 if (readbuf
== NULL
)
5404 pid
= lwpid_of (get_thread_lwp (current_inferior
));
5405 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5406 is_elf64
= elf_64_file_p (filename
);
5407 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5409 if (priv
->r_debug
== 0)
5410 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5412 if (priv
->r_debug
== (CORE_ADDR
) -1 || priv
->r_debug
== 0)
5414 document
= xstrdup ("<library-list-svr4 version=\"1.0\"/>\n");
5418 int allocated
= 1024;
5420 const int ptr_size
= is_elf64
? 8 : 4;
5421 CORE_ADDR lm_addr
, lm_prev
, l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5422 int r_version
, header_done
= 0;
5424 document
= xmalloc (allocated
);
5425 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5426 p
= document
+ strlen (document
);
5429 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5430 (unsigned char *) &r_version
,
5431 sizeof (r_version
)) != 0
5434 warning ("unexpected r_debug version %d", r_version
);
5438 if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5439 &lm_addr
, ptr_size
) != 0)
5441 warning ("unable to read r_map from 0x%lx",
5442 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5447 while (read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5448 &l_name
, ptr_size
) == 0
5449 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5450 &l_addr
, ptr_size
) == 0
5451 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5452 &l_ld
, ptr_size
) == 0
5453 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5454 &l_prev
, ptr_size
) == 0
5455 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5456 &l_next
, ptr_size
) == 0)
5458 unsigned char libname
[PATH_MAX
];
5460 if (lm_prev
!= l_prev
)
5462 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5463 (long) lm_prev
, (long) l_prev
);
5467 /* Not checking for error because reading may stop before
5468 we've got PATH_MAX worth of characters. */
5470 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5471 libname
[sizeof (libname
) - 1] = '\0';
5472 if (libname
[0] != '\0')
5474 /* 6x the size for xml_escape_text below. */
5475 size_t len
= 6 * strlen ((char *) libname
);
5480 /* Terminate `<library-list-svr4'. */
5485 while (allocated
< p
- document
+ len
+ 200)
5487 /* Expand to guarantee sufficient storage. */
5488 uintptr_t document_len
= p
- document
;
5490 document
= xrealloc (document
, 2 * allocated
);
5492 p
= document
+ document_len
;
5495 name
= xml_escape_text ((char *) libname
);
5496 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
5497 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5498 name
, (unsigned long) lm_addr
,
5499 (unsigned long) l_addr
, (unsigned long) l_ld
);
5502 else if (lm_prev
== 0)
5504 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5515 strcpy (p
, "</library-list-svr4>");
5518 document_len
= strlen (document
);
5519 if (offset
< document_len
)
5520 document_len
-= offset
;
5523 if (len
> document_len
)
5526 memcpy (readbuf
, document
+ offset
, len
);
5532 static struct target_ops linux_target_ops
= {
5533 linux_create_inferior
,
5542 linux_fetch_registers
,
5543 linux_store_registers
,
5544 linux_prepare_to_access_memory
,
5545 linux_done_accessing_memory
,
5548 linux_look_up_symbols
,
5549 linux_request_interrupt
,
5553 linux_stopped_by_watchpoint
,
5554 linux_stopped_data_address
,
5555 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
5560 #ifdef USE_THREAD_DB
5561 thread_db_get_tls_address
,
5566 hostio_last_error_from_errno
,
5569 linux_supports_non_stop
,
5571 linux_start_non_stop
,
5572 linux_supports_multi_process
,
5573 #ifdef USE_THREAD_DB
5574 thread_db_handle_monitor_command
,
5578 linux_common_core_of_thread
,
5580 linux_process_qsupported
,
5581 linux_supports_tracepoints
,
5584 linux_thread_stopped
,
5588 linux_cancel_breakpoints
,
5589 linux_stabilize_threads
,
5590 linux_install_fast_tracepoint_jump_pad
,
5592 linux_supports_disable_randomization
,
5593 linux_get_min_fast_tracepoint_insn_len
,
5594 linux_qxfer_libraries_svr4
,
5595 linux_supports_agent
,
5599 linux_init_signals ()
5601 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5602 to find what the cancel signal actually is. */
5603 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
5604 signal (__SIGRTMIN
+1, SIG_IGN
);
5609 initialize_low (void)
5611 struct sigaction sigchld_action
;
5612 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
5613 set_target_ops (&linux_target_ops
);
5614 set_breakpoint_data (the_low_target
.breakpoint
,
5615 the_low_target
.breakpoint_len
);
5616 linux_init_signals ();
5617 linux_test_for_tracefork ();
5618 #ifdef HAVE_LINUX_REGSETS
5619 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
5621 disabled_regsets
= xmalloc (num_regsets
);
5624 sigchld_action
.sa_handler
= sigchld_handler
;
5625 sigemptyset (&sigchld_action
.sa_mask
);
5626 sigchld_action
.sa_flags
= SA_RESTART
;
5627 sigaction (SIGCHLD
, &sigchld_action
, NULL
);