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 #ifndef HAVE_ELF32_AUXV_T
86 /* Copied from glibc's elf.h. */
89 uint32_t a_type
; /* Entry type */
92 uint32_t a_val
; /* Integer value */
93 /* We use to have pointer elements added here. We cannot do that,
94 though, since it does not work when using 32-bit definitions
95 on 64-bit platforms and vice versa. */
100 #ifndef HAVE_ELF64_AUXV_T
101 /* Copied from glibc's elf.h. */
104 uint64_t a_type
; /* Entry type */
107 uint64_t a_val
; /* Integer value */
108 /* We use to have pointer elements added here. We cannot do that,
109 though, since it does not work when using 32-bit definitions
110 on 64-bit platforms and vice versa. */
115 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
116 representation of the thread ID.
118 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
119 the same as the LWP ID.
121 ``all_processes'' is keyed by the "overall process ID", which
122 GNU/Linux calls tgid, "thread group ID". */
124 struct inferior_list all_lwps
;
126 /* A list of all unknown processes which receive stop signals. Some
127 other process will presumably claim each of these as forked
128 children momentarily. */
130 struct simple_pid_list
132 /* The process ID. */
135 /* The status as reported by waitpid. */
139 struct simple_pid_list
*next
;
141 struct simple_pid_list
*stopped_pids
;
143 /* Trivial list manipulation functions to keep track of a list of new
144 stopped processes. */
147 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
149 struct simple_pid_list
*new_pid
= xmalloc (sizeof (struct simple_pid_list
));
152 new_pid
->status
= status
;
153 new_pid
->next
= *listp
;
158 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
160 struct simple_pid_list
**p
;
162 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
163 if ((*p
)->pid
== pid
)
165 struct simple_pid_list
*next
= (*p
)->next
;
167 *statusp
= (*p
)->status
;
175 /* FIXME this is a bit of a hack, and could be removed. */
176 int stopping_threads
;
178 /* FIXME make into a target method? */
179 int using_threads
= 1;
181 /* True if we're presently stabilizing threads (moving them out of
183 static int stabilizing_threads
;
185 /* This flag is true iff we've just created or attached to our first
186 inferior but it has not stopped yet. As soon as it does, we need
187 to call the low target's arch_setup callback. Doing this only on
188 the first inferior avoids reinializing the architecture on every
189 inferior, and avoids messing with the register caches of the
190 already running inferiors. NOTE: this assumes all inferiors under
191 control of gdbserver have the same architecture. */
192 static int new_inferior
;
194 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
195 int step
, int signal
, siginfo_t
*info
);
196 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
197 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
198 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
199 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
200 static void *add_lwp (ptid_t ptid
);
201 static int linux_stopped_by_watchpoint (void);
202 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
203 static void proceed_all_lwps (void);
204 static int finish_step_over (struct lwp_info
*lwp
);
205 static CORE_ADDR
get_stop_pc (struct lwp_info
*lwp
);
206 static int kill_lwp (unsigned long lwpid
, int signo
);
207 static void linux_enable_event_reporting (int pid
);
209 /* True if the low target can hardware single-step. Such targets
210 don't need a BREAKPOINT_REINSERT_ADDR callback. */
213 can_hardware_single_step (void)
215 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
218 /* True if the low target supports memory breakpoints. If so, we'll
219 have a GET_PC implementation. */
222 supports_breakpoints (void)
224 return (the_low_target
.get_pc
!= NULL
);
227 /* Returns true if this target can support fast tracepoints. This
228 does not mean that the in-process agent has been loaded in the
232 supports_fast_tracepoints (void)
234 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
237 struct pending_signals
241 struct pending_signals
*prev
;
244 #define PTRACE_ARG3_TYPE void *
245 #define PTRACE_ARG4_TYPE void *
246 #define PTRACE_XFER_TYPE long
248 #ifdef HAVE_LINUX_REGSETS
249 static char *disabled_regsets
;
250 static int num_regsets
;
253 /* The read/write ends of the pipe registered as waitable file in the
255 static int linux_event_pipe
[2] = { -1, -1 };
257 /* True if we're currently in async mode. */
258 #define target_is_async_p() (linux_event_pipe[0] != -1)
260 static void send_sigstop (struct lwp_info
*lwp
);
261 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
263 /* Return non-zero if HEADER is a 64-bit ELF file. */
266 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
268 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
269 && header
->e_ident
[EI_MAG1
] == ELFMAG1
270 && header
->e_ident
[EI_MAG2
] == ELFMAG2
271 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
273 *machine
= header
->e_machine
;
274 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
281 /* Return non-zero if FILE is a 64-bit ELF file,
282 zero if the file is not a 64-bit ELF file,
283 and -1 if the file is not accessible or doesn't exist. */
286 elf_64_file_p (const char *file
, unsigned int *machine
)
291 fd
= open (file
, O_RDONLY
);
295 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
302 return elf_64_header_p (&header
, machine
);
305 /* Accepts an integer PID; Returns true if the executable PID is
306 running is a 64-bit ELF file.. */
309 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
311 char file
[MAXPATHLEN
];
313 sprintf (file
, "/proc/%d/exe", pid
);
314 return elf_64_file_p (file
, machine
);
318 delete_lwp (struct lwp_info
*lwp
)
320 remove_thread (get_lwp_thread (lwp
));
321 remove_inferior (&all_lwps
, &lwp
->head
);
322 free (lwp
->arch_private
);
326 /* Add a process to the common process list, and set its private
329 static struct process_info
*
330 linux_add_process (int pid
, int attached
)
332 struct process_info
*proc
;
334 /* Is this the first process? If so, then set the arch. */
335 if (all_processes
.head
== NULL
)
338 proc
= add_process (pid
, attached
);
339 proc
->private = xcalloc (1, sizeof (*proc
->private));
341 if (the_low_target
.new_process
!= NULL
)
342 proc
->private->arch_private
= the_low_target
.new_process ();
347 /* Wrapper function for waitpid which handles EINTR, and emulates
348 __WALL for systems where that is not available. */
351 my_waitpid (int pid
, int *status
, int flags
)
356 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
360 sigset_t block_mask
, org_mask
, wake_mask
;
363 wnohang
= (flags
& WNOHANG
) != 0;
364 flags
&= ~(__WALL
| __WCLONE
);
367 /* Block all signals while here. This avoids knowing about
368 LinuxThread's signals. */
369 sigfillset (&block_mask
);
370 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
372 /* ... except during the sigsuspend below. */
373 sigemptyset (&wake_mask
);
377 /* Since all signals are blocked, there's no need to check
379 ret
= waitpid (pid
, status
, flags
);
382 if (ret
== -1 && out_errno
!= ECHILD
)
387 if (flags
& __WCLONE
)
389 /* We've tried both flavors now. If WNOHANG is set,
390 there's nothing else to do, just bail out. */
395 fprintf (stderr
, "blocking\n");
397 /* Block waiting for signals. */
398 sigsuspend (&wake_mask
);
404 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
409 ret
= waitpid (pid
, status
, flags
);
410 while (ret
== -1 && errno
== EINTR
);
415 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
416 pid
, flags
, status
? *status
: -1, ret
);
422 /* Handle a GNU/Linux extended wait response. If we see a clone
423 event, we need to add the new LWP to our list (and not report the
424 trap to higher layers). */
427 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
429 int event
= wstat
>> 16;
430 struct lwp_info
*new_lwp
;
432 if (event
== PTRACE_EVENT_CLONE
)
435 unsigned long new_pid
;
438 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), 0, &new_pid
);
440 /* If we haven't already seen the new PID stop, wait for it now. */
441 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
443 /* The new child has a pending SIGSTOP. We can't affect it until it
444 hits the SIGSTOP, but we're already attached. */
446 ret
= my_waitpid (new_pid
, &status
, __WALL
);
449 perror_with_name ("waiting for new child");
450 else if (ret
!= new_pid
)
451 warning ("wait returned unexpected PID %d", ret
);
452 else if (!WIFSTOPPED (status
))
453 warning ("wait returned unexpected status 0x%x", status
);
456 linux_enable_event_reporting (new_pid
);
458 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
459 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
460 add_thread (ptid
, new_lwp
);
462 /* Either we're going to immediately resume the new thread
463 or leave it stopped. linux_resume_one_lwp is a nop if it
464 thinks the thread is currently running, so set this first
465 before calling linux_resume_one_lwp. */
466 new_lwp
->stopped
= 1;
468 /* Normally we will get the pending SIGSTOP. But in some cases
469 we might get another signal delivered to the group first.
470 If we do get another signal, be sure not to lose it. */
471 if (WSTOPSIG (status
) == SIGSTOP
)
473 if (stopping_threads
)
474 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
476 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
480 new_lwp
->stop_expected
= 1;
482 if (stopping_threads
)
484 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
485 new_lwp
->status_pending_p
= 1;
486 new_lwp
->status_pending
= status
;
489 /* Pass the signal on. This is what GDB does - except
490 shouldn't we really report it instead? */
491 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
494 /* Always resume the current thread. If we are stopping
495 threads, it will have a pending SIGSTOP; we may as well
497 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
501 /* Return the PC as read from the regcache of LWP, without any
505 get_pc (struct lwp_info
*lwp
)
507 struct thread_info
*saved_inferior
;
508 struct regcache
*regcache
;
511 if (the_low_target
.get_pc
== NULL
)
514 saved_inferior
= current_inferior
;
515 current_inferior
= get_lwp_thread (lwp
);
517 regcache
= get_thread_regcache (current_inferior
, 1);
518 pc
= (*the_low_target
.get_pc
) (regcache
);
521 fprintf (stderr
, "pc is 0x%lx\n", (long) pc
);
523 current_inferior
= saved_inferior
;
527 /* This function should only be called if LWP got a SIGTRAP.
528 The SIGTRAP could mean several things.
530 On i386, where decr_pc_after_break is non-zero:
531 If we were single-stepping this process using PTRACE_SINGLESTEP,
532 we will get only the one SIGTRAP (even if the instruction we
533 stepped over was a breakpoint). The value of $eip will be the
535 If we continue the process using PTRACE_CONT, we will get a
536 SIGTRAP when we hit a breakpoint. The value of $eip will be
537 the instruction after the breakpoint (i.e. needs to be
538 decremented). If we report the SIGTRAP to GDB, we must also
539 report the undecremented PC. If we cancel the SIGTRAP, we
540 must resume at the decremented PC.
542 (Presumably, not yet tested) On a non-decr_pc_after_break machine
543 with hardware or kernel single-step:
544 If we single-step over a breakpoint instruction, our PC will
545 point at the following instruction. If we continue and hit a
546 breakpoint instruction, our PC will point at the breakpoint
550 get_stop_pc (struct lwp_info
*lwp
)
554 if (the_low_target
.get_pc
== NULL
)
557 stop_pc
= get_pc (lwp
);
559 if (WSTOPSIG (lwp
->last_status
) == SIGTRAP
561 && !lwp
->stopped_by_watchpoint
562 && lwp
->last_status
>> 16 == 0)
563 stop_pc
-= the_low_target
.decr_pc_after_break
;
566 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
572 add_lwp (ptid_t ptid
)
574 struct lwp_info
*lwp
;
576 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
577 memset (lwp
, 0, sizeof (*lwp
));
581 if (the_low_target
.new_thread
!= NULL
)
582 lwp
->arch_private
= the_low_target
.new_thread ();
584 add_inferior_to_list (&all_lwps
, &lwp
->head
);
589 /* Start an inferior process and returns its pid.
590 ALLARGS is a vector of program-name and args. */
593 linux_create_inferior (char *program
, char **allargs
)
595 #ifdef HAVE_PERSONALITY
596 int personality_orig
= 0, personality_set
= 0;
598 struct lwp_info
*new_lwp
;
602 #ifdef HAVE_PERSONALITY
603 if (disable_randomization
)
606 personality_orig
= personality (0xffffffff);
607 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
610 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
612 if (errno
!= 0 || (personality_set
613 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
614 warning ("Error disabling address space randomization: %s",
619 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
625 perror_with_name ("fork");
629 ptrace (PTRACE_TRACEME
, 0, 0, 0);
631 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
632 signal (__SIGRTMIN
+ 1, SIG_DFL
);
637 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
638 stdout to stderr so that inferior i/o doesn't corrupt the connection.
639 Also, redirect stdin to /dev/null. */
640 if (remote_connection_is_stdio ())
643 open ("/dev/null", O_RDONLY
);
645 if (write (2, "stdin/stdout redirected\n",
646 sizeof ("stdin/stdout redirected\n") - 1) < 0)
647 /* Errors ignored. */;
650 execv (program
, allargs
);
652 execvp (program
, allargs
);
654 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
660 #ifdef HAVE_PERSONALITY
664 personality (personality_orig
);
666 warning ("Error restoring address space randomization: %s",
671 linux_add_process (pid
, 0);
673 ptid
= ptid_build (pid
, pid
, 0);
674 new_lwp
= add_lwp (ptid
);
675 add_thread (ptid
, new_lwp
);
676 new_lwp
->must_set_ptrace_flags
= 1;
681 /* Attach to an inferior process. */
684 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
687 struct lwp_info
*new_lwp
;
689 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) != 0)
691 struct buffer buffer
;
695 /* If we fail to attach to an LWP, just warn. */
696 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
697 strerror (errno
), errno
);
702 /* If we fail to attach to a process, report an error. */
703 buffer_init (&buffer
);
704 linux_ptrace_attach_warnings (lwpid
, &buffer
);
705 buffer_grow_str0 (&buffer
, "");
706 error ("%sCannot attach to lwp %ld: %s (%d)", buffer_finish (&buffer
),
707 lwpid
, strerror (errno
), errno
);
711 /* If lwp is the tgid, we handle adding existing threads later.
712 Otherwise we just add lwp without bothering about any other
714 ptid
= ptid_build (lwpid
, lwpid
, 0);
717 /* Note that extracting the pid from the current inferior is
718 safe, since we're always called in the context of the same
719 process as this new thread. */
720 int pid
= pid_of (get_thread_lwp (current_inferior
));
721 ptid
= ptid_build (pid
, lwpid
, 0);
724 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
725 add_thread (ptid
, new_lwp
);
727 /* We need to wait for SIGSTOP before being able to make the next
728 ptrace call on this LWP. */
729 new_lwp
->must_set_ptrace_flags
= 1;
731 if (linux_proc_pid_is_stopped (lwpid
))
735 "Attached to a stopped process\n");
737 /* The process is definitely stopped. It is in a job control
738 stop, unless the kernel predates the TASK_STOPPED /
739 TASK_TRACED distinction, in which case it might be in a
740 ptrace stop. Make sure it is in a ptrace stop; from there we
741 can kill it, signal it, et cetera.
743 First make sure there is a pending SIGSTOP. Since we are
744 already attached, the process can not transition from stopped
745 to running without a PTRACE_CONT; so we know this signal will
746 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
747 probably already in the queue (unless this kernel is old
748 enough to use TASK_STOPPED for ptrace stops); but since
749 SIGSTOP is not an RT signal, it can only be queued once. */
750 kill_lwp (lwpid
, SIGSTOP
);
752 /* Finally, resume the stopped process. This will deliver the
753 SIGSTOP (or a higher priority signal, just like normal
754 PTRACE_ATTACH), which we'll catch later on. */
755 ptrace (PTRACE_CONT
, lwpid
, 0, 0);
758 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
761 There are several cases to consider here:
763 1) gdbserver has already attached to the process and is being notified
764 of a new thread that is being created.
765 In this case we should ignore that SIGSTOP and resume the
766 process. This is handled below by setting stop_expected = 1,
767 and the fact that add_thread sets last_resume_kind ==
770 2) This is the first thread (the process thread), and we're attaching
771 to it via attach_inferior.
772 In this case we want the process thread to stop.
773 This is handled by having linux_attach set last_resume_kind ==
774 resume_stop after we return.
776 If the pid we are attaching to is also the tgid, we attach to and
777 stop all the existing threads. Otherwise, we attach to pid and
778 ignore any other threads in the same group as this pid.
780 3) GDB is connecting to gdbserver and is requesting an enumeration of all
782 In this case we want the thread to stop.
783 FIXME: This case is currently not properly handled.
784 We should wait for the SIGSTOP but don't. Things work apparently
785 because enough time passes between when we ptrace (ATTACH) and when
786 gdb makes the next ptrace call on the thread.
788 On the other hand, if we are currently trying to stop all threads, we
789 should treat the new thread as if we had sent it a SIGSTOP. This works
790 because we are guaranteed that the add_lwp call above added us to the
791 end of the list, and so the new thread has not yet reached
792 wait_for_sigstop (but will). */
793 new_lwp
->stop_expected
= 1;
797 linux_attach_lwp (unsigned long lwpid
)
799 linux_attach_lwp_1 (lwpid
, 0);
802 /* Attach to PID. If PID is the tgid, attach to it and all
806 linux_attach (unsigned long pid
)
808 /* Attach to PID. We will check for other threads
810 linux_attach_lwp_1 (pid
, 1);
811 linux_add_process (pid
, 1);
815 struct thread_info
*thread
;
817 /* Don't ignore the initial SIGSTOP if we just attached to this
818 process. It will be collected by wait shortly. */
819 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
820 thread
->last_resume_kind
= resume_stop
;
823 if (linux_proc_get_tgid (pid
) == pid
)
828 sprintf (pathname
, "/proc/%ld/task", pid
);
830 dir
= opendir (pathname
);
834 fprintf (stderr
, "Could not open /proc/%ld/task.\n", pid
);
839 /* At this point we attached to the tgid. Scan the task for
842 int new_threads_found
;
846 while (iterations
< 2)
848 new_threads_found
= 0;
849 /* Add all the other threads. While we go through the
850 threads, new threads may be spawned. Cycle through
851 the list of threads until we have done two iterations without
852 finding new threads. */
853 while ((dp
= readdir (dir
)) != NULL
)
856 lwp
= strtoul (dp
->d_name
, NULL
, 10);
858 /* Is this a new thread? */
860 && find_thread_ptid (ptid_build (pid
, lwp
, 0)) == NULL
)
862 linux_attach_lwp_1 (lwp
, 0);
867 Found and attached to new lwp %ld\n", lwp
);
871 if (!new_threads_found
)
892 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
894 struct counter
*counter
= args
;
896 if (ptid_get_pid (entry
->id
) == counter
->pid
)
898 if (++counter
->count
> 1)
906 last_thread_of_process_p (struct thread_info
*thread
)
908 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
909 int pid
= ptid_get_pid (ptid
);
910 struct counter counter
= { pid
, 0 };
912 return (find_inferior (&all_threads
,
913 second_thread_of_pid_p
, &counter
) == NULL
);
919 linux_kill_one_lwp (struct lwp_info
*lwp
)
921 int pid
= lwpid_of (lwp
);
923 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
924 there is no signal context, and ptrace(PTRACE_KILL) (or
925 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
926 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
927 alternative is to kill with SIGKILL. We only need one SIGKILL
928 per process, not one for each thread. But since we still support
929 linuxthreads, and we also support debugging programs using raw
930 clone without CLONE_THREAD, we send one for each thread. For
931 years, we used PTRACE_KILL only, so we're being a bit paranoid
932 about some old kernels where PTRACE_KILL might work better
933 (dubious if there are any such, but that's why it's paranoia), so
934 we try SIGKILL first, PTRACE_KILL second, and so we're fine
941 "LKL: kill (SIGKILL) %s, 0, 0 (%s)\n",
942 target_pid_to_str (ptid_of (lwp
)),
943 errno
? strerror (errno
) : "OK");
946 ptrace (PTRACE_KILL
, pid
, 0, 0);
949 "LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
950 target_pid_to_str (ptid_of (lwp
)),
951 errno
? strerror (errno
) : "OK");
954 /* Callback for `find_inferior'. Kills an lwp of a given process,
955 except the leader. */
958 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
960 struct thread_info
*thread
= (struct thread_info
*) entry
;
961 struct lwp_info
*lwp
= get_thread_lwp (thread
);
963 int pid
= * (int *) args
;
965 if (ptid_get_pid (entry
->id
) != pid
)
968 /* We avoid killing the first thread here, because of a Linux kernel (at
969 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
970 the children get a chance to be reaped, it will remain a zombie
973 if (lwpid_of (lwp
) == pid
)
976 fprintf (stderr
, "lkop: is last of process %s\n",
977 target_pid_to_str (entry
->id
));
983 linux_kill_one_lwp (lwp
);
985 /* Make sure it died. The loop is most likely unnecessary. */
986 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
987 } while (pid
> 0 && WIFSTOPPED (wstat
));
995 struct process_info
*process
;
996 struct lwp_info
*lwp
;
1000 process
= find_process_pid (pid
);
1001 if (process
== NULL
)
1004 /* If we're killing a running inferior, make sure it is stopped
1005 first, as PTRACE_KILL will not work otherwise. */
1006 stop_all_lwps (0, NULL
);
1008 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1010 /* See the comment in linux_kill_one_lwp. We did not kill the first
1011 thread in the list, so do so now. */
1012 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1017 fprintf (stderr
, "lk_1: cannot find lwp %ld, for pid: %d\n",
1018 lwpid_of (lwp
), pid
);
1023 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
1024 lwpid_of (lwp
), pid
);
1028 linux_kill_one_lwp (lwp
);
1030 /* Make sure it died. The loop is most likely unnecessary. */
1031 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
1032 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
1035 the_target
->mourn (process
);
1037 /* Since we presently can only stop all lwps of all processes, we
1038 need to unstop lwps of other processes. */
1039 unstop_all_lwps (0, NULL
);
1043 /* Get pending signal of THREAD, for detaching purposes. This is the
1044 signal the thread last stopped for, which we need to deliver to the
1045 thread when detaching, otherwise, it'd be suppressed/lost. */
1048 get_detach_signal (struct thread_info
*thread
)
1050 enum target_signal signo
= TARGET_SIGNAL_0
;
1052 struct lwp_info
*lp
= get_thread_lwp (thread
);
1054 if (lp
->status_pending_p
)
1055 status
= lp
->status_pending
;
1058 /* If the thread had been suspended by gdbserver, and it stopped
1059 cleanly, then it'll have stopped with SIGSTOP. But we don't
1060 want to deliver that SIGSTOP. */
1061 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1062 || thread
->last_status
.value
.sig
== TARGET_SIGNAL_0
)
1065 /* Otherwise, we may need to deliver the signal we
1067 status
= lp
->last_status
;
1070 if (!WIFSTOPPED (status
))
1074 "GPS: lwp %s hasn't stopped: no pending signal\n",
1075 target_pid_to_str (ptid_of (lp
)));
1079 /* Extended wait statuses aren't real SIGTRAPs. */
1080 if (WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
1084 "GPS: lwp %s had stopped with extended "
1085 "status: no pending signal\n",
1086 target_pid_to_str (ptid_of (lp
)));
1090 signo
= target_signal_from_host (WSTOPSIG (status
));
1092 if (program_signals_p
&& !program_signals
[signo
])
1096 "GPS: lwp %s had signal %s, but it is in nopass state\n",
1097 target_pid_to_str (ptid_of (lp
)),
1098 target_signal_to_string (signo
));
1101 else if (!program_signals_p
1102 /* If we have no way to know which signals GDB does not
1103 want to have passed to the program, assume
1104 SIGTRAP/SIGINT, which is GDB's default. */
1105 && (signo
== TARGET_SIGNAL_TRAP
|| signo
== TARGET_SIGNAL_INT
))
1109 "GPS: lwp %s had signal %s, "
1110 "but we don't know if we should pass it. Default to not.\n",
1111 target_pid_to_str (ptid_of (lp
)),
1112 target_signal_to_string (signo
));
1119 "GPS: lwp %s has pending signal %s: delivering it.\n",
1120 target_pid_to_str (ptid_of (lp
)),
1121 target_signal_to_string (signo
));
1123 return WSTOPSIG (status
);
1128 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1130 struct thread_info
*thread
= (struct thread_info
*) entry
;
1131 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1132 int pid
= * (int *) args
;
1135 if (ptid_get_pid (entry
->id
) != pid
)
1138 /* If there is a pending SIGSTOP, get rid of it. */
1139 if (lwp
->stop_expected
)
1143 "Sending SIGCONT to %s\n",
1144 target_pid_to_str (ptid_of (lwp
)));
1146 kill_lwp (lwpid_of (lwp
), SIGCONT
);
1147 lwp
->stop_expected
= 0;
1150 /* Flush any pending changes to the process's registers. */
1151 regcache_invalidate_one ((struct inferior_list_entry
*)
1152 get_lwp_thread (lwp
));
1154 /* Pass on any pending signal for this thread. */
1155 sig
= get_detach_signal (thread
);
1157 /* Finally, let it resume. */
1158 if (the_low_target
.prepare_to_resume
!= NULL
)
1159 the_low_target
.prepare_to_resume (lwp
);
1160 if (ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0, sig
) < 0)
1161 error (_("Can't detach %s: %s"),
1162 target_pid_to_str (ptid_of (lwp
)),
1170 linux_detach (int pid
)
1172 struct process_info
*process
;
1174 process
= find_process_pid (pid
);
1175 if (process
== NULL
)
1178 /* Stop all threads before detaching. First, ptrace requires that
1179 the thread is stopped to sucessfully detach. Second, thread_db
1180 may need to uninstall thread event breakpoints from memory, which
1181 only works with a stopped process anyway. */
1182 stop_all_lwps (0, NULL
);
1184 #ifdef USE_THREAD_DB
1185 thread_db_detach (process
);
1188 /* Stabilize threads (move out of jump pads). */
1189 stabilize_threads ();
1191 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1193 the_target
->mourn (process
);
1195 /* Since we presently can only stop all lwps of all processes, we
1196 need to unstop lwps of other processes. */
1197 unstop_all_lwps (0, NULL
);
1201 /* Remove all LWPs that belong to process PROC from the lwp list. */
1204 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1206 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1207 struct process_info
*process
= proc
;
1209 if (pid_of (lwp
) == pid_of (process
))
1216 linux_mourn (struct process_info
*process
)
1218 struct process_info_private
*priv
;
1220 #ifdef USE_THREAD_DB
1221 thread_db_mourn (process
);
1224 find_inferior (&all_lwps
, delete_lwp_callback
, process
);
1226 /* Freeing all private data. */
1227 priv
= process
->private;
1228 free (priv
->arch_private
);
1230 process
->private = NULL
;
1232 remove_process (process
);
1236 linux_join (int pid
)
1241 ret
= my_waitpid (pid
, &status
, 0);
1242 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1244 } while (ret
!= -1 || errno
!= ECHILD
);
1247 /* Return nonzero if the given thread is still alive. */
1249 linux_thread_alive (ptid_t ptid
)
1251 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1253 /* We assume we always know if a thread exits. If a whole process
1254 exited but we still haven't been able to report it to GDB, we'll
1255 hold on to the last lwp of the dead process. */
1262 /* Return 1 if this lwp has an interesting status pending. */
1264 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1266 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1267 ptid_t ptid
= * (ptid_t
*) arg
;
1268 struct thread_info
*thread
;
1270 /* Check if we're only interested in events from a specific process
1272 if (!ptid_equal (minus_one_ptid
, ptid
)
1273 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
1276 thread
= get_lwp_thread (lwp
);
1278 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1279 report any status pending the LWP may have. */
1280 if (thread
->last_resume_kind
== resume_stop
1281 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1284 return lwp
->status_pending_p
;
1288 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1290 ptid_t ptid
= *(ptid_t
*) data
;
1293 if (ptid_get_lwp (ptid
) != 0)
1294 lwp
= ptid_get_lwp (ptid
);
1296 lwp
= ptid_get_pid (ptid
);
1298 if (ptid_get_lwp (entry
->id
) == lwp
)
1305 find_lwp_pid (ptid_t ptid
)
1307 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
1310 static struct lwp_info
*
1311 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
1314 int to_wait_for
= -1;
1315 struct lwp_info
*child
= NULL
;
1318 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1320 if (ptid_equal (ptid
, minus_one_ptid
))
1321 to_wait_for
= -1; /* any child */
1323 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1329 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1330 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1333 perror_with_name ("waitpid");
1336 && (!WIFSTOPPED (*wstatp
)
1337 || (WSTOPSIG (*wstatp
) != 32
1338 && WSTOPSIG (*wstatp
) != 33)))
1339 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1341 child
= find_lwp_pid (pid_to_ptid (ret
));
1343 /* If we didn't find a process, one of two things presumably happened:
1344 - A process we started and then detached from has exited. Ignore it.
1345 - A process we are controlling has forked and the new child's stop
1346 was reported to us by the kernel. Save its PID. */
1347 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1349 add_to_pid_list (&stopped_pids
, ret
, *wstatp
);
1352 else if (child
== NULL
)
1357 child
->last_status
= *wstatp
;
1359 /* Architecture-specific setup after inferior is running.
1360 This needs to happen after we have attached to the inferior
1361 and it is stopped for the first time, but before we access
1362 any inferior registers. */
1365 the_low_target
.arch_setup ();
1366 #ifdef HAVE_LINUX_REGSETS
1367 memset (disabled_regsets
, 0, num_regsets
);
1372 /* Fetch the possibly triggered data watchpoint info and store it in
1375 On some archs, like x86, that use debug registers to set
1376 watchpoints, it's possible that the way to know which watched
1377 address trapped, is to check the register that is used to select
1378 which address to watch. Problem is, between setting the
1379 watchpoint and reading back which data address trapped, the user
1380 may change the set of watchpoints, and, as a consequence, GDB
1381 changes the debug registers in the inferior. To avoid reading
1382 back a stale stopped-data-address when that happens, we cache in
1383 LP the fact that a watchpoint trapped, and the corresponding data
1384 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1385 changes the debug registers meanwhile, we have the cached data we
1388 if (WIFSTOPPED (*wstatp
) && WSTOPSIG (*wstatp
) == SIGTRAP
)
1390 if (the_low_target
.stopped_by_watchpoint
== NULL
)
1392 child
->stopped_by_watchpoint
= 0;
1396 struct thread_info
*saved_inferior
;
1398 saved_inferior
= current_inferior
;
1399 current_inferior
= get_lwp_thread (child
);
1401 child
->stopped_by_watchpoint
1402 = the_low_target
.stopped_by_watchpoint ();
1404 if (child
->stopped_by_watchpoint
)
1406 if (the_low_target
.stopped_data_address
!= NULL
)
1407 child
->stopped_data_address
1408 = the_low_target
.stopped_data_address ();
1410 child
->stopped_data_address
= 0;
1413 current_inferior
= saved_inferior
;
1417 /* Store the STOP_PC, with adjustment applied. This depends on the
1418 architecture being defined already (so that CHILD has a valid
1419 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1421 if (WIFSTOPPED (*wstatp
))
1422 child
->stop_pc
= get_stop_pc (child
);
1425 && WIFSTOPPED (*wstatp
)
1426 && the_low_target
.get_pc
!= NULL
)
1428 struct thread_info
*saved_inferior
= current_inferior
;
1429 struct regcache
*regcache
;
1432 current_inferior
= get_lwp_thread (child
);
1433 regcache
= get_thread_regcache (current_inferior
, 1);
1434 pc
= (*the_low_target
.get_pc
) (regcache
);
1435 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1436 current_inferior
= saved_inferior
;
1442 /* This function should only be called if the LWP got a SIGTRAP.
1444 Handle any tracepoint steps or hits. Return true if a tracepoint
1445 event was handled, 0 otherwise. */
1448 handle_tracepoints (struct lwp_info
*lwp
)
1450 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1451 int tpoint_related_event
= 0;
1453 /* If this tracepoint hit causes a tracing stop, we'll immediately
1454 uninsert tracepoints. To do this, we temporarily pause all
1455 threads, unpatch away, and then unpause threads. We need to make
1456 sure the unpausing doesn't resume LWP too. */
1459 /* And we need to be sure that any all-threads-stopping doesn't try
1460 to move threads out of the jump pads, as it could deadlock the
1461 inferior (LWP could be in the jump pad, maybe even holding the
1464 /* Do any necessary step collect actions. */
1465 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1467 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1469 /* See if we just hit a tracepoint and do its main collect
1471 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1475 gdb_assert (lwp
->suspended
== 0);
1476 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1478 if (tpoint_related_event
)
1481 fprintf (stderr
, "got a tracepoint event\n");
1488 /* Convenience wrapper. Returns true if LWP is presently collecting a
1492 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1493 struct fast_tpoint_collect_status
*status
)
1495 CORE_ADDR thread_area
;
1497 if (the_low_target
.get_thread_area
== NULL
)
1500 /* Get the thread area address. This is used to recognize which
1501 thread is which when tracing with the in-process agent library.
1502 We don't read anything from the address, and treat it as opaque;
1503 it's the address itself that we assume is unique per-thread. */
1504 if ((*the_low_target
.get_thread_area
) (lwpid_of (lwp
), &thread_area
) == -1)
1507 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1510 /* The reason we resume in the caller, is because we want to be able
1511 to pass lwp->status_pending as WSTAT, and we need to clear
1512 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1513 refuses to resume. */
1516 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1518 struct thread_info
*saved_inferior
;
1520 saved_inferior
= current_inferior
;
1521 current_inferior
= get_lwp_thread (lwp
);
1524 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1525 && supports_fast_tracepoints ()
1526 && agent_loaded_p ())
1528 struct fast_tpoint_collect_status status
;
1533 Checking whether LWP %ld needs to move out of the jump pad.\n",
1536 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1539 || (WSTOPSIG (*wstat
) != SIGILL
1540 && WSTOPSIG (*wstat
) != SIGFPE
1541 && WSTOPSIG (*wstat
) != SIGSEGV
1542 && WSTOPSIG (*wstat
) != SIGBUS
))
1544 lwp
->collecting_fast_tracepoint
= r
;
1548 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1550 /* Haven't executed the original instruction yet.
1551 Set breakpoint there, and wait till it's hit,
1552 then single-step until exiting the jump pad. */
1553 lwp
->exit_jump_pad_bkpt
1554 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1559 Checking whether LWP %ld needs to move out of the jump pad...it does\n",
1561 current_inferior
= saved_inferior
;
1568 /* If we get a synchronous signal while collecting, *and*
1569 while executing the (relocated) original instruction,
1570 reset the PC to point at the tpoint address, before
1571 reporting to GDB. Otherwise, it's an IPA lib bug: just
1572 report the signal to GDB, and pray for the best. */
1574 lwp
->collecting_fast_tracepoint
= 0;
1577 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1578 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1581 struct regcache
*regcache
;
1583 /* The si_addr on a few signals references the address
1584 of the faulting instruction. Adjust that as
1586 if ((WSTOPSIG (*wstat
) == SIGILL
1587 || WSTOPSIG (*wstat
) == SIGFPE
1588 || WSTOPSIG (*wstat
) == SIGBUS
1589 || WSTOPSIG (*wstat
) == SIGSEGV
)
1590 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &info
) == 0
1591 /* Final check just to make sure we don't clobber
1592 the siginfo of non-kernel-sent signals. */
1593 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1595 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1596 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &info
);
1599 regcache
= get_thread_regcache (get_lwp_thread (lwp
), 1);
1600 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1601 lwp
->stop_pc
= status
.tpoint_addr
;
1603 /* Cancel any fast tracepoint lock this thread was
1605 force_unlock_trace_buffer ();
1608 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1612 "Cancelling fast exit-jump-pad: removing bkpt. "
1613 "stopping all threads momentarily.\n");
1615 stop_all_lwps (1, lwp
);
1616 cancel_breakpoints ();
1618 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1619 lwp
->exit_jump_pad_bkpt
= NULL
;
1621 unstop_all_lwps (1, lwp
);
1623 gdb_assert (lwp
->suspended
>= 0);
1630 Checking whether LWP %ld needs to move out of the jump pad...no\n",
1633 current_inferior
= saved_inferior
;
1637 /* Enqueue one signal in the "signals to report later when out of the
1641 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1643 struct pending_signals
*p_sig
;
1647 Deferring signal %d for LWP %ld.\n", WSTOPSIG (*wstat
), lwpid_of (lwp
));
1651 struct pending_signals
*sig
;
1653 for (sig
= lwp
->pending_signals_to_report
;
1657 " Already queued %d\n",
1660 fprintf (stderr
, " (no more currently queued signals)\n");
1663 /* Don't enqueue non-RT signals if they are already in the deferred
1664 queue. (SIGSTOP being the easiest signal to see ending up here
1666 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1668 struct pending_signals
*sig
;
1670 for (sig
= lwp
->pending_signals_to_report
;
1674 if (sig
->signal
== WSTOPSIG (*wstat
))
1678 "Not requeuing already queued non-RT signal %d"
1687 p_sig
= xmalloc (sizeof (*p_sig
));
1688 p_sig
->prev
= lwp
->pending_signals_to_report
;
1689 p_sig
->signal
= WSTOPSIG (*wstat
);
1690 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1691 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
1693 lwp
->pending_signals_to_report
= p_sig
;
1696 /* Dequeue one signal from the "signals to report later when out of
1697 the jump pad" list. */
1700 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1702 if (lwp
->pending_signals_to_report
!= NULL
)
1704 struct pending_signals
**p_sig
;
1706 p_sig
= &lwp
->pending_signals_to_report
;
1707 while ((*p_sig
)->prev
!= NULL
)
1708 p_sig
= &(*p_sig
)->prev
;
1710 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1711 if ((*p_sig
)->info
.si_signo
!= 0)
1712 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
1717 fprintf (stderr
, "Reporting deferred signal %d for LWP %ld.\n",
1718 WSTOPSIG (*wstat
), lwpid_of (lwp
));
1722 struct pending_signals
*sig
;
1724 for (sig
= lwp
->pending_signals_to_report
;
1728 " Still queued %d\n",
1731 fprintf (stderr
, " (no more queued signals)\n");
1740 /* Arrange for a breakpoint to be hit again later. We don't keep the
1741 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1742 will handle the current event, eventually we will resume this LWP,
1743 and this breakpoint will trap again. */
1746 cancel_breakpoint (struct lwp_info
*lwp
)
1748 struct thread_info
*saved_inferior
;
1750 /* There's nothing to do if we don't support breakpoints. */
1751 if (!supports_breakpoints ())
1754 /* breakpoint_at reads from current inferior. */
1755 saved_inferior
= current_inferior
;
1756 current_inferior
= get_lwp_thread (lwp
);
1758 if ((*the_low_target
.breakpoint_at
) (lwp
->stop_pc
))
1762 "CB: Push back breakpoint for %s\n",
1763 target_pid_to_str (ptid_of (lwp
)));
1765 /* Back up the PC if necessary. */
1766 if (the_low_target
.decr_pc_after_break
)
1768 struct regcache
*regcache
1769 = get_thread_regcache (current_inferior
, 1);
1770 (*the_low_target
.set_pc
) (regcache
, lwp
->stop_pc
);
1773 current_inferior
= saved_inferior
;
1780 "CB: No breakpoint found at %s for [%s]\n",
1781 paddress (lwp
->stop_pc
),
1782 target_pid_to_str (ptid_of (lwp
)));
1785 current_inferior
= saved_inferior
;
1789 /* When the event-loop is doing a step-over, this points at the thread
1791 ptid_t step_over_bkpt
;
1793 /* Wait for an event from child PID. If PID is -1, wait for any
1794 child. Store the stop status through the status pointer WSTAT.
1795 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1796 event was found and OPTIONS contains WNOHANG. Return the PID of
1797 the stopped child otherwise. */
1800 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1802 struct lwp_info
*event_child
, *requested_child
;
1806 requested_child
= NULL
;
1808 /* Check for a lwp with a pending status. */
1810 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
1812 event_child
= (struct lwp_info
*)
1813 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1814 if (debug_threads
&& event_child
)
1815 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1819 requested_child
= find_lwp_pid (ptid
);
1821 if (!stopping_threads
1822 && requested_child
->status_pending_p
1823 && requested_child
->collecting_fast_tracepoint
)
1825 enqueue_one_deferred_signal (requested_child
,
1826 &requested_child
->status_pending
);
1827 requested_child
->status_pending_p
= 0;
1828 requested_child
->status_pending
= 0;
1829 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
1832 if (requested_child
->suspended
1833 && requested_child
->status_pending_p
)
1834 fatal ("requesting an event out of a suspended child?");
1836 if (requested_child
->status_pending_p
)
1837 event_child
= requested_child
;
1840 if (event_child
!= NULL
)
1843 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1844 lwpid_of (event_child
), event_child
->status_pending
);
1845 *wstat
= event_child
->status_pending
;
1846 event_child
->status_pending_p
= 0;
1847 event_child
->status_pending
= 0;
1848 current_inferior
= get_lwp_thread (event_child
);
1849 return lwpid_of (event_child
);
1852 if (ptid_is_pid (ptid
))
1854 /* A request to wait for a specific tgid. This is not possible
1855 with waitpid, so instead, we wait for any child, and leave
1856 children we're not interested in right now with a pending
1857 status to report later. */
1858 wait_ptid
= minus_one_ptid
;
1863 /* We only enter this loop if no process has a pending wait status. Thus
1864 any action taken in response to a wait status inside this loop is
1865 responding as soon as we detect the status, not after any pending
1869 event_child
= linux_wait_for_lwp (wait_ptid
, wstat
, options
);
1871 if ((options
& WNOHANG
) && event_child
== NULL
)
1874 fprintf (stderr
, "WNOHANG set, no event found\n");
1878 if (event_child
== NULL
)
1879 error ("event from unknown child");
1881 if (ptid_is_pid (ptid
)
1882 && ptid_get_pid (ptid
) != ptid_get_pid (ptid_of (event_child
)))
1884 if (! WIFSTOPPED (*wstat
))
1885 mark_lwp_dead (event_child
, *wstat
);
1888 event_child
->status_pending_p
= 1;
1889 event_child
->status_pending
= *wstat
;
1894 current_inferior
= get_lwp_thread (event_child
);
1896 /* Check for thread exit. */
1897 if (! WIFSTOPPED (*wstat
))
1900 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1902 /* If the last thread is exiting, just return. */
1903 if (last_thread_of_process_p (current_inferior
))
1906 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1907 lwpid_of (event_child
));
1908 return lwpid_of (event_child
);
1913 current_inferior
= (struct thread_info
*) all_threads
.head
;
1915 fprintf (stderr
, "Current inferior is now %ld\n",
1916 lwpid_of (get_thread_lwp (current_inferior
)));
1920 current_inferior
= NULL
;
1922 fprintf (stderr
, "Current inferior is now <NULL>\n");
1925 /* If we were waiting for this particular child to do something...
1926 well, it did something. */
1927 if (requested_child
!= NULL
)
1929 int lwpid
= lwpid_of (event_child
);
1931 /* Cancel the step-over operation --- the thread that
1932 started it is gone. */
1933 if (finish_step_over (event_child
))
1934 unstop_all_lwps (1, event_child
);
1935 delete_lwp (event_child
);
1939 delete_lwp (event_child
);
1941 /* Wait for a more interesting event. */
1945 if (event_child
->must_set_ptrace_flags
)
1947 linux_enable_event_reporting (lwpid_of (event_child
));
1948 event_child
->must_set_ptrace_flags
= 0;
1951 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1952 && *wstat
>> 16 != 0)
1954 handle_extended_wait (event_child
, *wstat
);
1958 if (WIFSTOPPED (*wstat
)
1959 && WSTOPSIG (*wstat
) == SIGSTOP
1960 && event_child
->stop_expected
)
1965 fprintf (stderr
, "Expected stop.\n");
1966 event_child
->stop_expected
= 0;
1968 should_stop
= (current_inferior
->last_resume_kind
== resume_stop
1969 || stopping_threads
);
1973 linux_resume_one_lwp (event_child
,
1974 event_child
->stepping
, 0, NULL
);
1979 return lwpid_of (event_child
);
1986 /* Count the LWP's that have had events. */
1989 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
1991 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1992 struct thread_info
*thread
= get_lwp_thread (lp
);
1995 gdb_assert (count
!= NULL
);
1997 /* Count only resumed LWPs that have a SIGTRAP event pending that
1998 should be reported to GDB. */
1999 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2000 && thread
->last_resume_kind
!= resume_stop
2001 && lp
->status_pending_p
2002 && WIFSTOPPED (lp
->status_pending
)
2003 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2004 && !breakpoint_inserted_here (lp
->stop_pc
))
2010 /* Select the LWP (if any) that is currently being single-stepped. */
2013 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2015 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2016 struct thread_info
*thread
= get_lwp_thread (lp
);
2018 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2019 && thread
->last_resume_kind
== resume_step
2020 && lp
->status_pending_p
)
2026 /* Select the Nth LWP that has had a SIGTRAP event that should be
2030 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2032 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2033 struct thread_info
*thread
= get_lwp_thread (lp
);
2034 int *selector
= data
;
2036 gdb_assert (selector
!= NULL
);
2038 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2039 if (thread
->last_resume_kind
!= resume_stop
2040 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2041 && lp
->status_pending_p
2042 && WIFSTOPPED (lp
->status_pending
)
2043 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2044 && !breakpoint_inserted_here (lp
->stop_pc
))
2045 if ((*selector
)-- == 0)
2052 cancel_breakpoints_callback (struct inferior_list_entry
*entry
, void *data
)
2054 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2055 struct thread_info
*thread
= get_lwp_thread (lp
);
2056 struct lwp_info
*event_lp
= data
;
2058 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
2062 /* If a LWP other than the LWP that we're reporting an event for has
2063 hit a GDB breakpoint (as opposed to some random trap signal),
2064 then just arrange for it to hit it again later. We don't keep
2065 the SIGTRAP status and don't forward the SIGTRAP signal to the
2066 LWP. We will handle the current event, eventually we will resume
2067 all LWPs, and this one will get its breakpoint trap again.
2069 If we do not do this, then we run the risk that the user will
2070 delete or disable the breakpoint, but the LWP will have already
2073 if (thread
->last_resume_kind
!= resume_stop
2074 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2075 && lp
->status_pending_p
2076 && WIFSTOPPED (lp
->status_pending
)
2077 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2079 && !lp
->stopped_by_watchpoint
2080 && cancel_breakpoint (lp
))
2081 /* Throw away the SIGTRAP. */
2082 lp
->status_pending_p
= 0;
2088 linux_cancel_breakpoints (void)
2090 find_inferior (&all_lwps
, cancel_breakpoints_callback
, NULL
);
2093 /* Select one LWP out of those that have events pending. */
2096 select_event_lwp (struct lwp_info
**orig_lp
)
2099 int random_selector
;
2100 struct lwp_info
*event_lp
;
2102 /* Give preference to any LWP that is being single-stepped. */
2104 = (struct lwp_info
*) find_inferior (&all_lwps
,
2105 select_singlestep_lwp_callback
, NULL
);
2106 if (event_lp
!= NULL
)
2110 "SEL: Select single-step %s\n",
2111 target_pid_to_str (ptid_of (event_lp
)));
2115 /* No single-stepping LWP. Select one at random, out of those
2116 which have had SIGTRAP events. */
2118 /* First see how many SIGTRAP events we have. */
2119 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
2121 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
2122 random_selector
= (int)
2123 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2125 if (debug_threads
&& num_events
> 1)
2127 "SEL: Found %d SIGTRAP events, selecting #%d\n",
2128 num_events
, random_selector
);
2130 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
2131 select_event_lwp_callback
,
2135 if (event_lp
!= NULL
)
2137 /* Switch the event LWP. */
2138 *orig_lp
= event_lp
;
2142 /* Decrement the suspend count of an LWP. */
2145 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2147 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2149 /* Ignore EXCEPT. */
2155 gdb_assert (lwp
->suspended
>= 0);
2159 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2163 unsuspend_all_lwps (struct lwp_info
*except
)
2165 find_inferior (&all_lwps
, unsuspend_one_lwp
, except
);
2168 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2169 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2171 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2172 static ptid_t
linux_wait_1 (ptid_t ptid
,
2173 struct target_waitstatus
*ourstatus
,
2174 int target_options
);
2176 /* Stabilize threads (move out of jump pads).
2178 If a thread is midway collecting a fast tracepoint, we need to
2179 finish the collection and move it out of the jump pad before
2180 reporting the signal.
2182 This avoids recursion while collecting (when a signal arrives
2183 midway, and the signal handler itself collects), which would trash
2184 the trace buffer. In case the user set a breakpoint in a signal
2185 handler, this avoids the backtrace showing the jump pad, etc..
2186 Most importantly, there are certain things we can't do safely if
2187 threads are stopped in a jump pad (or in its callee's). For
2190 - starting a new trace run. A thread still collecting the
2191 previous run, could trash the trace buffer when resumed. The trace
2192 buffer control structures would have been reset but the thread had
2193 no way to tell. The thread could even midway memcpy'ing to the
2194 buffer, which would mean that when resumed, it would clobber the
2195 trace buffer that had been set for a new run.
2197 - we can't rewrite/reuse the jump pads for new tracepoints
2198 safely. Say you do tstart while a thread is stopped midway while
2199 collecting. When the thread is later resumed, it finishes the
2200 collection, and returns to the jump pad, to execute the original
2201 instruction that was under the tracepoint jump at the time the
2202 older run had been started. If the jump pad had been rewritten
2203 since for something else in the new run, the thread would now
2204 execute the wrong / random instructions. */
2207 linux_stabilize_threads (void)
2209 struct thread_info
*save_inferior
;
2210 struct lwp_info
*lwp_stuck
;
2213 = (struct lwp_info
*) find_inferior (&all_lwps
,
2214 stuck_in_jump_pad_callback
, NULL
);
2215 if (lwp_stuck
!= NULL
)
2218 fprintf (stderr
, "can't stabilize, LWP %ld is stuck in jump pad\n",
2219 lwpid_of (lwp_stuck
));
2223 save_inferior
= current_inferior
;
2225 stabilizing_threads
= 1;
2228 for_each_inferior (&all_lwps
, move_out_of_jump_pad_callback
);
2230 /* Loop until all are stopped out of the jump pads. */
2231 while (find_inferior (&all_lwps
, lwp_running
, NULL
) != NULL
)
2233 struct target_waitstatus ourstatus
;
2234 struct lwp_info
*lwp
;
2237 /* Note that we go through the full wait even loop. While
2238 moving threads out of jump pad, we need to be able to step
2239 over internal breakpoints and such. */
2240 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2242 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2244 lwp
= get_thread_lwp (current_inferior
);
2249 if (ourstatus
.value
.sig
!= TARGET_SIGNAL_0
2250 || current_inferior
->last_resume_kind
== resume_stop
)
2252 wstat
= W_STOPCODE (target_signal_to_host (ourstatus
.value
.sig
));
2253 enqueue_one_deferred_signal (lwp
, &wstat
);
2258 find_inferior (&all_lwps
, unsuspend_one_lwp
, NULL
);
2260 stabilizing_threads
= 0;
2262 current_inferior
= save_inferior
;
2267 = (struct lwp_info
*) find_inferior (&all_lwps
,
2268 stuck_in_jump_pad_callback
, NULL
);
2269 if (lwp_stuck
!= NULL
)
2270 fprintf (stderr
, "couldn't stabilize, LWP %ld got stuck in jump pad\n",
2271 lwpid_of (lwp_stuck
));
2275 /* Wait for process, returns status. */
2278 linux_wait_1 (ptid_t ptid
,
2279 struct target_waitstatus
*ourstatus
, int target_options
)
2282 struct lwp_info
*event_child
;
2285 int step_over_finished
;
2286 int bp_explains_trap
;
2287 int maybe_internal_trap
;
2291 /* Translate generic target options into linux options. */
2293 if (target_options
& TARGET_WNOHANG
)
2297 bp_explains_trap
= 0;
2299 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2301 /* If we were only supposed to resume one thread, only wait for
2302 that thread - if it's still alive. If it died, however - which
2303 can happen if we're coming from the thread death case below -
2304 then we need to make sure we restart the other threads. We could
2305 pick a thread at random or restart all; restarting all is less
2308 && !ptid_equal (cont_thread
, null_ptid
)
2309 && !ptid_equal (cont_thread
, minus_one_ptid
))
2311 struct thread_info
*thread
;
2313 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
2316 /* No stepping, no signal - unless one is pending already, of course. */
2319 struct thread_resume resume_info
;
2320 resume_info
.thread
= minus_one_ptid
;
2321 resume_info
.kind
= resume_continue
;
2322 resume_info
.sig
= 0;
2323 linux_resume (&resume_info
, 1);
2329 if (ptid_equal (step_over_bkpt
, null_ptid
))
2330 pid
= linux_wait_for_event (ptid
, &w
, options
);
2334 fprintf (stderr
, "step_over_bkpt set [%s], doing a blocking wait\n",
2335 target_pid_to_str (step_over_bkpt
));
2336 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2339 if (pid
== 0) /* only if TARGET_WNOHANG */
2342 event_child
= get_thread_lwp (current_inferior
);
2344 /* If we are waiting for a particular child, and it exited,
2345 linux_wait_for_event will return its exit status. Similarly if
2346 the last child exited. If this is not the last child, however,
2347 do not report it as exited until there is a 'thread exited' response
2348 available in the remote protocol. Instead, just wait for another event.
2349 This should be safe, because if the thread crashed we will already
2350 have reported the termination signal to GDB; that should stop any
2351 in-progress stepping operations, etc.
2353 Report the exit status of the last thread to exit. This matches
2354 LinuxThreads' behavior. */
2356 if (last_thread_of_process_p (current_inferior
))
2358 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2362 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2363 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2367 "\nChild exited with retcode = %x \n",
2372 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2373 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
2377 "\nChild terminated with signal = %x \n",
2382 return ptid_of (event_child
);
2387 if (!WIFSTOPPED (w
))
2391 /* If this event was not handled before, and is not a SIGTRAP, we
2392 report it. SIGILL and SIGSEGV are also treated as traps in case
2393 a breakpoint is inserted at the current PC. If this target does
2394 not support internal breakpoints at all, we also report the
2395 SIGTRAP without further processing; it's of no concern to us. */
2397 = (supports_breakpoints ()
2398 && (WSTOPSIG (w
) == SIGTRAP
2399 || ((WSTOPSIG (w
) == SIGILL
2400 || WSTOPSIG (w
) == SIGSEGV
)
2401 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2403 if (maybe_internal_trap
)
2405 /* Handle anything that requires bookkeeping before deciding to
2406 report the event or continue waiting. */
2408 /* First check if we can explain the SIGTRAP with an internal
2409 breakpoint, or if we should possibly report the event to GDB.
2410 Do this before anything that may remove or insert a
2412 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2414 /* We have a SIGTRAP, possibly a step-over dance has just
2415 finished. If so, tweak the state machine accordingly,
2416 reinsert breakpoints and delete any reinsert (software
2417 single-step) breakpoints. */
2418 step_over_finished
= finish_step_over (event_child
);
2420 /* Now invoke the callbacks of any internal breakpoints there. */
2421 check_breakpoints (event_child
->stop_pc
);
2423 /* Handle tracepoint data collecting. This may overflow the
2424 trace buffer, and cause a tracing stop, removing
2426 trace_event
= handle_tracepoints (event_child
);
2428 if (bp_explains_trap
)
2430 /* If we stepped or ran into an internal breakpoint, we've
2431 already handled it. So next time we resume (from this
2432 PC), we should step over it. */
2434 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2436 if (breakpoint_here (event_child
->stop_pc
))
2437 event_child
->need_step_over
= 1;
2442 /* We have some other signal, possibly a step-over dance was in
2443 progress, and it should be cancelled too. */
2444 step_over_finished
= finish_step_over (event_child
);
2447 /* We have all the data we need. Either report the event to GDB, or
2448 resume threads and keep waiting for more. */
2450 /* If we're collecting a fast tracepoint, finish the collection and
2451 move out of the jump pad before delivering a signal. See
2452 linux_stabilize_threads. */
2455 && WSTOPSIG (w
) != SIGTRAP
2456 && supports_fast_tracepoints ()
2457 && agent_loaded_p ())
2461 "Got signal %d for LWP %ld. Check if we need "
2462 "to defer or adjust it.\n",
2463 WSTOPSIG (w
), lwpid_of (event_child
));
2465 /* Allow debugging the jump pad itself. */
2466 if (current_inferior
->last_resume_kind
!= resume_step
2467 && maybe_move_out_of_jump_pad (event_child
, &w
))
2469 enqueue_one_deferred_signal (event_child
, &w
);
2473 "Signal %d for LWP %ld deferred (in jump pad)\n",
2474 WSTOPSIG (w
), lwpid_of (event_child
));
2476 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2481 if (event_child
->collecting_fast_tracepoint
)
2485 LWP %ld was trying to move out of the jump pad (%d). \
2486 Check if we're already there.\n",
2487 lwpid_of (event_child
),
2488 event_child
->collecting_fast_tracepoint
);
2492 event_child
->collecting_fast_tracepoint
2493 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2495 if (event_child
->collecting_fast_tracepoint
!= 1)
2497 /* No longer need this breakpoint. */
2498 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2502 "No longer need exit-jump-pad bkpt; removing it."
2503 "stopping all threads momentarily.\n");
2505 /* Other running threads could hit this breakpoint.
2506 We don't handle moribund locations like GDB does,
2507 instead we always pause all threads when removing
2508 breakpoints, so that any step-over or
2509 decr_pc_after_break adjustment is always taken
2510 care of while the breakpoint is still
2512 stop_all_lwps (1, event_child
);
2513 cancel_breakpoints ();
2515 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2516 event_child
->exit_jump_pad_bkpt
= NULL
;
2518 unstop_all_lwps (1, event_child
);
2520 gdb_assert (event_child
->suspended
>= 0);
2524 if (event_child
->collecting_fast_tracepoint
== 0)
2528 "fast tracepoint finished "
2529 "collecting successfully.\n");
2531 /* We may have a deferred signal to report. */
2532 if (dequeue_one_deferred_signal (event_child
, &w
))
2535 fprintf (stderr
, "dequeued one signal.\n");
2540 fprintf (stderr
, "no deferred signals.\n");
2542 if (stabilizing_threads
)
2544 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2545 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2546 return ptid_of (event_child
);
2552 /* Check whether GDB would be interested in this event. */
2554 /* If GDB is not interested in this signal, don't stop other
2555 threads, and don't report it to GDB. Just resume the inferior
2556 right away. We do this for threading-related signals as well as
2557 any that GDB specifically requested we ignore. But never ignore
2558 SIGSTOP if we sent it ourselves, and do not ignore signals when
2559 stepping - they may require special handling to skip the signal
2561 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2564 && current_inferior
->last_resume_kind
!= resume_step
2566 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2567 (current_process ()->private->thread_db
!= NULL
2568 && (WSTOPSIG (w
) == __SIGRTMIN
2569 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2572 (pass_signals
[target_signal_from_host (WSTOPSIG (w
))]
2573 && !(WSTOPSIG (w
) == SIGSTOP
2574 && current_inferior
->last_resume_kind
== resume_stop
))))
2576 siginfo_t info
, *info_p
;
2579 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
2580 WSTOPSIG (w
), lwpid_of (event_child
));
2582 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
2586 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2587 WSTOPSIG (w
), info_p
);
2591 /* If GDB wanted this thread to single step, we always want to
2592 report the SIGTRAP, and let GDB handle it. Watchpoints should
2593 always be reported. So should signals we can't explain. A
2594 SIGTRAP we can't explain could be a GDB breakpoint --- we may or
2595 not support Z0 breakpoints. If we do, we're be able to handle
2596 GDB breakpoints on top of internal breakpoints, by handling the
2597 internal breakpoint and still reporting the event to GDB. If we
2598 don't, we're out of luck, GDB won't see the breakpoint hit. */
2599 report_to_gdb
= (!maybe_internal_trap
2600 || current_inferior
->last_resume_kind
== resume_step
2601 || event_child
->stopped_by_watchpoint
2602 || (!step_over_finished
2603 && !bp_explains_trap
&& !trace_event
)
2604 || (gdb_breakpoint_here (event_child
->stop_pc
)
2605 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)));
2607 /* We found no reason GDB would want us to stop. We either hit one
2608 of our own breakpoints, or finished an internal step GDB
2609 shouldn't know about. */
2614 if (bp_explains_trap
)
2615 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2616 if (step_over_finished
)
2617 fprintf (stderr
, "Step-over finished.\n");
2619 fprintf (stderr
, "Tracepoint event.\n");
2622 /* We're not reporting this breakpoint to GDB, so apply the
2623 decr_pc_after_break adjustment to the inferior's regcache
2626 if (the_low_target
.set_pc
!= NULL
)
2628 struct regcache
*regcache
2629 = get_thread_regcache (get_lwp_thread (event_child
), 1);
2630 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2633 /* We may have finished stepping over a breakpoint. If so,
2634 we've stopped and suspended all LWPs momentarily except the
2635 stepping one. This is where we resume them all again. We're
2636 going to keep waiting, so use proceed, which handles stepping
2637 over the next breakpoint. */
2639 fprintf (stderr
, "proceeding all threads.\n");
2641 if (step_over_finished
)
2642 unsuspend_all_lwps (event_child
);
2644 proceed_all_lwps ();
2650 if (current_inferior
->last_resume_kind
== resume_step
)
2651 fprintf (stderr
, "GDB wanted to single-step, reporting event.\n");
2652 if (event_child
->stopped_by_watchpoint
)
2653 fprintf (stderr
, "Stopped by watchpoint.\n");
2654 if (gdb_breakpoint_here (event_child
->stop_pc
))
2655 fprintf (stderr
, "Stopped by GDB breakpoint.\n");
2657 fprintf (stderr
, "Hit a non-gdbserver trap event.\n");
2660 /* Alright, we're going to report a stop. */
2662 if (!non_stop
&& !stabilizing_threads
)
2664 /* In all-stop, stop all threads. */
2665 stop_all_lwps (0, NULL
);
2667 /* If we're not waiting for a specific LWP, choose an event LWP
2668 from among those that have had events. Giving equal priority
2669 to all LWPs that have had events helps prevent
2671 if (ptid_equal (ptid
, minus_one_ptid
))
2673 event_child
->status_pending_p
= 1;
2674 event_child
->status_pending
= w
;
2676 select_event_lwp (&event_child
);
2678 event_child
->status_pending_p
= 0;
2679 w
= event_child
->status_pending
;
2682 /* Now that we've selected our final event LWP, cancel any
2683 breakpoints in other LWPs that have hit a GDB breakpoint.
2684 See the comment in cancel_breakpoints_callback to find out
2686 find_inferior (&all_lwps
, cancel_breakpoints_callback
, event_child
);
2688 /* If we were going a step-over, all other threads but the stepping one
2689 had been paused in start_step_over, with their suspend counts
2690 incremented. We don't want to do a full unstop/unpause, because we're
2691 in all-stop mode (so we want threads stopped), but we still need to
2692 unsuspend the other threads, to decrement their `suspended' count
2694 if (step_over_finished
)
2695 unsuspend_all_lwps (event_child
);
2697 /* Stabilize threads (move out of jump pads). */
2698 stabilize_threads ();
2702 /* If we just finished a step-over, then all threads had been
2703 momentarily paused. In all-stop, that's fine, we want
2704 threads stopped by now anyway. In non-stop, we need to
2705 re-resume threads that GDB wanted to be running. */
2706 if (step_over_finished
)
2707 unstop_all_lwps (1, event_child
);
2710 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2712 if (current_inferior
->last_resume_kind
== resume_stop
2713 && WSTOPSIG (w
) == SIGSTOP
)
2715 /* A thread that has been requested to stop by GDB with vCont;t,
2716 and it stopped cleanly, so report as SIG0. The use of
2717 SIGSTOP is an implementation detail. */
2718 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2720 else if (current_inferior
->last_resume_kind
== resume_stop
2721 && WSTOPSIG (w
) != SIGSTOP
)
2723 /* A thread that has been requested to stop by GDB with vCont;t,
2724 but, it stopped for other reasons. */
2725 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2729 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2732 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
2735 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
2736 target_pid_to_str (ptid_of (event_child
)),
2738 ourstatus
->value
.sig
);
2740 return ptid_of (event_child
);
2743 /* Get rid of any pending event in the pipe. */
2745 async_file_flush (void)
2751 ret
= read (linux_event_pipe
[0], &buf
, 1);
2752 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
2755 /* Put something in the pipe, so the event loop wakes up. */
2757 async_file_mark (void)
2761 async_file_flush ();
2764 ret
= write (linux_event_pipe
[1], "+", 1);
2765 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
2767 /* Ignore EAGAIN. If the pipe is full, the event loop will already
2768 be awakened anyway. */
2772 linux_wait (ptid_t ptid
,
2773 struct target_waitstatus
*ourstatus
, int target_options
)
2778 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
2780 /* Flush the async file first. */
2781 if (target_is_async_p ())
2782 async_file_flush ();
2784 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
2786 /* If at least one stop was reported, there may be more. A single
2787 SIGCHLD can signal more than one child stop. */
2788 if (target_is_async_p ()
2789 && (target_options
& TARGET_WNOHANG
) != 0
2790 && !ptid_equal (event_ptid
, null_ptid
))
2796 /* Send a signal to an LWP. */
2799 kill_lwp (unsigned long lwpid
, int signo
)
2801 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2802 fails, then we are not using nptl threads and we should be using kill. */
2806 static int tkill_failed
;
2813 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2814 if (errno
!= ENOSYS
)
2821 return kill (lwpid
, signo
);
2825 linux_stop_lwp (struct lwp_info
*lwp
)
2831 send_sigstop (struct lwp_info
*lwp
)
2835 pid
= lwpid_of (lwp
);
2837 /* If we already have a pending stop signal for this process, don't
2839 if (lwp
->stop_expected
)
2842 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
2848 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
2850 lwp
->stop_expected
= 1;
2851 kill_lwp (pid
, SIGSTOP
);
2855 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
2857 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2859 /* Ignore EXCEPT. */
2870 /* Increment the suspend count of an LWP, and stop it, if not stopped
2873 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
2876 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2878 /* Ignore EXCEPT. */
2884 return send_sigstop_callback (entry
, except
);
2888 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
2890 /* It's dead, really. */
2893 /* Store the exit status for later. */
2894 lwp
->status_pending_p
= 1;
2895 lwp
->status_pending
= wstat
;
2897 /* Prevent trying to stop it. */
2900 /* No further stops are expected from a dead lwp. */
2901 lwp
->stop_expected
= 0;
2905 wait_for_sigstop (struct inferior_list_entry
*entry
)
2907 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2908 struct thread_info
*saved_inferior
;
2917 fprintf (stderr
, "wait_for_sigstop: LWP %ld already stopped\n",
2922 saved_inferior
= current_inferior
;
2923 if (saved_inferior
!= NULL
)
2924 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
2926 saved_tid
= null_ptid
; /* avoid bogus unused warning */
2928 ptid
= lwp
->head
.id
;
2931 fprintf (stderr
, "wait_for_sigstop: pulling one event\n");
2933 pid
= linux_wait_for_event (ptid
, &wstat
, __WALL
);
2935 /* If we stopped with a non-SIGSTOP signal, save it for later
2936 and record the pending SIGSTOP. If the process exited, just
2938 if (WIFSTOPPED (wstat
))
2941 fprintf (stderr
, "LWP %ld stopped with signal %d\n",
2942 lwpid_of (lwp
), WSTOPSIG (wstat
));
2944 if (WSTOPSIG (wstat
) != SIGSTOP
)
2947 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
2948 lwpid_of (lwp
), wstat
);
2950 lwp
->status_pending_p
= 1;
2951 lwp
->status_pending
= wstat
;
2957 fprintf (stderr
, "Process %d exited while stopping LWPs\n", pid
);
2959 lwp
= find_lwp_pid (pid_to_ptid (pid
));
2962 /* Leave this status pending for the next time we're able to
2963 report it. In the mean time, we'll report this lwp as
2964 dead to GDB, so GDB doesn't try to read registers and
2965 memory from it. This can only happen if this was the
2966 last thread of the process; otherwise, PID is removed
2967 from the thread tables before linux_wait_for_event
2969 mark_lwp_dead (lwp
, wstat
);
2973 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
2974 current_inferior
= saved_inferior
;
2978 fprintf (stderr
, "Previously current thread died.\n");
2982 /* We can't change the current inferior behind GDB's back,
2983 otherwise, a subsequent command may apply to the wrong
2985 current_inferior
= NULL
;
2989 /* Set a valid thread as current. */
2990 set_desired_inferior (0);
2995 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
2996 move it out, because we need to report the stop event to GDB. For
2997 example, if the user puts a breakpoint in the jump pad, it's
2998 because she wants to debug it. */
3001 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3003 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3004 struct thread_info
*thread
= get_lwp_thread (lwp
);
3006 gdb_assert (lwp
->suspended
== 0);
3007 gdb_assert (lwp
->stopped
);
3009 /* Allow debugging the jump pad, gdb_collect, etc.. */
3010 return (supports_fast_tracepoints ()
3011 && agent_loaded_p ()
3012 && (gdb_breakpoint_here (lwp
->stop_pc
)
3013 || lwp
->stopped_by_watchpoint
3014 || thread
->last_resume_kind
== resume_step
)
3015 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3019 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3021 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3022 struct thread_info
*thread
= get_lwp_thread (lwp
);
3025 gdb_assert (lwp
->suspended
== 0);
3026 gdb_assert (lwp
->stopped
);
3028 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3030 /* Allow debugging the jump pad, gdb_collect, etc. */
3031 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3032 && !lwp
->stopped_by_watchpoint
3033 && thread
->last_resume_kind
!= resume_step
3034 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3038 "LWP %ld needs stabilizing (in jump pad)\n",
3043 lwp
->status_pending_p
= 0;
3044 enqueue_one_deferred_signal (lwp
, wstat
);
3048 "Signal %d for LWP %ld deferred "
3050 WSTOPSIG (*wstat
), lwpid_of (lwp
));
3053 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3060 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3062 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3071 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3072 If SUSPEND, then also increase the suspend count of every LWP,
3076 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3078 stopping_threads
= 1;
3081 find_inferior (&all_lwps
, suspend_and_send_sigstop_callback
, except
);
3083 find_inferior (&all_lwps
, send_sigstop_callback
, except
);
3084 for_each_inferior (&all_lwps
, wait_for_sigstop
);
3085 stopping_threads
= 0;
3088 /* Resume execution of the inferior process.
3089 If STEP is nonzero, single-step it.
3090 If SIGNAL is nonzero, give it that signal. */
3093 linux_resume_one_lwp (struct lwp_info
*lwp
,
3094 int step
, int signal
, siginfo_t
*info
)
3096 struct thread_info
*saved_inferior
;
3097 int fast_tp_collecting
;
3099 if (lwp
->stopped
== 0)
3102 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3104 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3106 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3107 user used the "jump" command, or "set $pc = foo"). */
3108 if (lwp
->stop_pc
!= get_pc (lwp
))
3110 /* Collecting 'while-stepping' actions doesn't make sense
3112 release_while_stepping_state_list (get_lwp_thread (lwp
));
3115 /* If we have pending signals or status, and a new signal, enqueue the
3116 signal. Also enqueue the signal if we are waiting to reinsert a
3117 breakpoint; it will be picked up again below. */
3119 && (lwp
->status_pending_p
3120 || lwp
->pending_signals
!= NULL
3121 || lwp
->bp_reinsert
!= 0
3122 || fast_tp_collecting
))
3124 struct pending_signals
*p_sig
;
3125 p_sig
= xmalloc (sizeof (*p_sig
));
3126 p_sig
->prev
= lwp
->pending_signals
;
3127 p_sig
->signal
= signal
;
3129 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3131 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3132 lwp
->pending_signals
= p_sig
;
3135 if (lwp
->status_pending_p
)
3138 fprintf (stderr
, "Not resuming lwp %ld (%s, signal %d, stop %s);"
3139 " has pending status\n",
3140 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3141 lwp
->stop_expected
? "expected" : "not expected");
3145 saved_inferior
= current_inferior
;
3146 current_inferior
= get_lwp_thread (lwp
);
3149 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
3150 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3151 lwp
->stop_expected
? "expected" : "not expected");
3153 /* This bit needs some thinking about. If we get a signal that
3154 we must report while a single-step reinsert is still pending,
3155 we often end up resuming the thread. It might be better to
3156 (ew) allow a stack of pending events; then we could be sure that
3157 the reinsert happened right away and not lose any signals.
3159 Making this stack would also shrink the window in which breakpoints are
3160 uninserted (see comment in linux_wait_for_lwp) but not enough for
3161 complete correctness, so it won't solve that problem. It may be
3162 worthwhile just to solve this one, however. */
3163 if (lwp
->bp_reinsert
!= 0)
3166 fprintf (stderr
, " pending reinsert at 0x%s\n",
3167 paddress (lwp
->bp_reinsert
));
3169 if (lwp
->bp_reinsert
!= 0 && can_hardware_single_step ())
3171 if (fast_tp_collecting
== 0)
3174 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
3176 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
3183 /* Postpone any pending signal. It was enqueued above. */
3187 if (fast_tp_collecting
== 1)
3191 lwp %ld wants to get out of fast tracepoint jump pad (exit-jump-pad-bkpt)\n",
3194 /* Postpone any pending signal. It was enqueued above. */
3197 else if (fast_tp_collecting
== 2)
3201 lwp %ld wants to get out of fast tracepoint jump pad single-stepping\n",
3204 if (can_hardware_single_step ())
3207 fatal ("moving out of jump pad single-stepping"
3208 " not implemented on this target");
3210 /* Postpone any pending signal. It was enqueued above. */
3214 /* If we have while-stepping actions in this thread set it stepping.
3215 If we have a signal to deliver, it may or may not be set to
3216 SIG_IGN, we don't know. Assume so, and allow collecting
3217 while-stepping into a signal handler. A possible smart thing to
3218 do would be to set an internal breakpoint at the signal return
3219 address, continue, and carry on catching this while-stepping
3220 action only when that breakpoint is hit. A future
3222 if (get_lwp_thread (lwp
)->while_stepping
!= NULL
3223 && can_hardware_single_step ())
3227 "lwp %ld has a while-stepping action -> forcing step.\n",
3232 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
3234 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
3235 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
3236 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
3239 /* If we have pending signals, consume one unless we are trying to
3240 reinsert a breakpoint or we're trying to finish a fast tracepoint
3242 if (lwp
->pending_signals
!= NULL
3243 && lwp
->bp_reinsert
== 0
3244 && fast_tp_collecting
== 0)
3246 struct pending_signals
**p_sig
;
3248 p_sig
= &lwp
->pending_signals
;
3249 while ((*p_sig
)->prev
!= NULL
)
3250 p_sig
= &(*p_sig
)->prev
;
3252 signal
= (*p_sig
)->signal
;
3253 if ((*p_sig
)->info
.si_signo
!= 0)
3254 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
3260 if (the_low_target
.prepare_to_resume
!= NULL
)
3261 the_low_target
.prepare_to_resume (lwp
);
3263 regcache_invalidate_one ((struct inferior_list_entry
*)
3264 get_lwp_thread (lwp
));
3267 lwp
->stopped_by_watchpoint
= 0;
3268 lwp
->stepping
= step
;
3269 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0,
3270 /* Coerce to a uintptr_t first to avoid potential gcc warning
3271 of coercing an 8 byte integer to a 4 byte pointer. */
3272 (PTRACE_ARG4_TYPE
) (uintptr_t) signal
);
3274 current_inferior
= saved_inferior
;
3277 /* ESRCH from ptrace either means that the thread was already
3278 running (an error) or that it is gone (a race condition). If
3279 it's gone, we will get a notification the next time we wait,
3280 so we can ignore the error. We could differentiate these
3281 two, but it's tricky without waiting; the thread still exists
3282 as a zombie, so sending it signal 0 would succeed. So just
3287 perror_with_name ("ptrace");
3291 struct thread_resume_array
3293 struct thread_resume
*resume
;
3297 /* This function is called once per thread. We look up the thread
3298 in RESUME_PTR, and mark the thread with a pointer to the appropriate
3301 This algorithm is O(threads * resume elements), but resume elements
3302 is small (and will remain small at least until GDB supports thread
3305 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3307 struct lwp_info
*lwp
;
3308 struct thread_info
*thread
;
3310 struct thread_resume_array
*r
;
3312 thread
= (struct thread_info
*) entry
;
3313 lwp
= get_thread_lwp (thread
);
3316 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3318 ptid_t ptid
= r
->resume
[ndx
].thread
;
3319 if (ptid_equal (ptid
, minus_one_ptid
)
3320 || ptid_equal (ptid
, entry
->id
)
3321 || (ptid_is_pid (ptid
)
3322 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
3323 || (ptid_get_lwp (ptid
) == -1
3324 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
3326 if (r
->resume
[ndx
].kind
== resume_stop
3327 && thread
->last_resume_kind
== resume_stop
)
3330 fprintf (stderr
, "already %s LWP %ld at GDB's request\n",
3331 thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
3339 lwp
->resume
= &r
->resume
[ndx
];
3340 thread
->last_resume_kind
= lwp
->resume
->kind
;
3342 /* If we had a deferred signal to report, dequeue one now.
3343 This can happen if LWP gets more than one signal while
3344 trying to get out of a jump pad. */
3346 && !lwp
->status_pending_p
3347 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3349 lwp
->status_pending_p
= 1;
3353 "Dequeueing deferred signal %d for LWP %ld, "
3354 "leaving status pending.\n",
3355 WSTOPSIG (lwp
->status_pending
), lwpid_of (lwp
));
3362 /* No resume action for this thread. */
3369 /* Set *FLAG_P if this lwp has an interesting status pending. */
3371 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3373 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3375 /* LWPs which will not be resumed are not interesting, because
3376 we might not wait for them next time through linux_wait. */
3377 if (lwp
->resume
== NULL
)
3380 if (lwp
->status_pending_p
)
3381 * (int *) flag_p
= 1;
3386 /* Return 1 if this lwp that GDB wants running is stopped at an
3387 internal breakpoint that we need to step over. It assumes that any
3388 required STOP_PC adjustment has already been propagated to the
3389 inferior's regcache. */
3392 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3394 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3395 struct thread_info
*thread
;
3396 struct thread_info
*saved_inferior
;
3399 /* LWPs which will not be resumed are not interesting, because we
3400 might not wait for them next time through linux_wait. */
3406 "Need step over [LWP %ld]? Ignoring, not stopped\n",
3411 thread
= get_lwp_thread (lwp
);
3413 if (thread
->last_resume_kind
== resume_stop
)
3417 "Need step over [LWP %ld]? Ignoring, should remain stopped\n",
3422 gdb_assert (lwp
->suspended
>= 0);
3428 "Need step over [LWP %ld]? Ignoring, suspended\n",
3433 if (!lwp
->need_step_over
)
3437 "Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
3440 if (lwp
->status_pending_p
)
3444 "Need step over [LWP %ld]? Ignoring, has pending status.\n",
3449 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3453 /* If the PC has changed since we stopped, then don't do anything,
3454 and let the breakpoint/tracepoint be hit. This happens if, for
3455 instance, GDB handled the decr_pc_after_break subtraction itself,
3456 GDB is OOL stepping this thread, or the user has issued a "jump"
3457 command, or poked thread's registers herself. */
3458 if (pc
!= lwp
->stop_pc
)
3462 "Need step over [LWP %ld]? Cancelling, PC was changed. "
3463 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3464 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
3466 lwp
->need_step_over
= 0;
3470 saved_inferior
= current_inferior
;
3471 current_inferior
= thread
;
3473 /* We can only step over breakpoints we know about. */
3474 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3476 /* Don't step over a breakpoint that GDB expects to hit
3477 though. If the condition is being evaluated on the target's side
3478 and it evaluate to false, step over this breakpoint as well. */
3479 if (gdb_breakpoint_here (pc
)
3480 && gdb_condition_true_at_breakpoint (pc
))
3484 "Need step over [LWP %ld]? yes, but found"
3485 " GDB breakpoint at 0x%s; skipping step over\n",
3486 lwpid_of (lwp
), paddress (pc
));
3488 current_inferior
= saved_inferior
;
3495 "Need step over [LWP %ld]? yes, "
3496 "found breakpoint at 0x%s\n",
3497 lwpid_of (lwp
), paddress (pc
));
3499 /* We've found an lwp that needs stepping over --- return 1 so
3500 that find_inferior stops looking. */
3501 current_inferior
= saved_inferior
;
3503 /* If the step over is cancelled, this is set again. */
3504 lwp
->need_step_over
= 0;
3509 current_inferior
= saved_inferior
;
3513 "Need step over [LWP %ld]? No, no breakpoint found at 0x%s\n",
3514 lwpid_of (lwp
), paddress (pc
));
3519 /* Start a step-over operation on LWP. When LWP stopped at a
3520 breakpoint, to make progress, we need to remove the breakpoint out
3521 of the way. If we let other threads run while we do that, they may
3522 pass by the breakpoint location and miss hitting it. To avoid
3523 that, a step-over momentarily stops all threads while LWP is
3524 single-stepped while the breakpoint is temporarily uninserted from
3525 the inferior. When the single-step finishes, we reinsert the
3526 breakpoint, and let all threads that are supposed to be running,
3529 On targets that don't support hardware single-step, we don't
3530 currently support full software single-stepping. Instead, we only
3531 support stepping over the thread event breakpoint, by asking the
3532 low target where to place a reinsert breakpoint. Since this
3533 routine assumes the breakpoint being stepped over is a thread event
3534 breakpoint, it usually assumes the return address of the current
3535 function is a good enough place to set the reinsert breakpoint. */
3538 start_step_over (struct lwp_info
*lwp
)
3540 struct thread_info
*saved_inferior
;
3546 "Starting step-over on LWP %ld. Stopping all threads\n",
3549 stop_all_lwps (1, lwp
);
3550 gdb_assert (lwp
->suspended
== 0);
3553 fprintf (stderr
, "Done stopping all threads for step-over.\n");
3555 /* Note, we should always reach here with an already adjusted PC,
3556 either by GDB (if we're resuming due to GDB's request), or by our
3557 caller, if we just finished handling an internal breakpoint GDB
3558 shouldn't care about. */
3561 saved_inferior
= current_inferior
;
3562 current_inferior
= get_lwp_thread (lwp
);
3564 lwp
->bp_reinsert
= pc
;
3565 uninsert_breakpoints_at (pc
);
3566 uninsert_fast_tracepoint_jumps_at (pc
);
3568 if (can_hardware_single_step ())
3574 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3575 set_reinsert_breakpoint (raddr
);
3579 current_inferior
= saved_inferior
;
3581 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3583 /* Require next event from this LWP. */
3584 step_over_bkpt
= lwp
->head
.id
;
3588 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3589 start_step_over, if still there, and delete any reinsert
3590 breakpoints we've set, on non hardware single-step targets. */
3593 finish_step_over (struct lwp_info
*lwp
)
3595 if (lwp
->bp_reinsert
!= 0)
3598 fprintf (stderr
, "Finished step over.\n");
3600 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3601 may be no breakpoint to reinsert there by now. */
3602 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3603 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3605 lwp
->bp_reinsert
= 0;
3607 /* Delete any software-single-step reinsert breakpoints. No
3608 longer needed. We don't have to worry about other threads
3609 hitting this trap, and later not being able to explain it,
3610 because we were stepping over a breakpoint, and we hold all
3611 threads but LWP stopped while doing that. */
3612 if (!can_hardware_single_step ())
3613 delete_reinsert_breakpoints ();
3615 step_over_bkpt
= null_ptid
;
3622 /* This function is called once per thread. We check the thread's resume
3623 request, which will tell us whether to resume, step, or leave the thread
3624 stopped; and what signal, if any, it should be sent.
3626 For threads which we aren't explicitly told otherwise, we preserve
3627 the stepping flag; this is used for stepping over gdbserver-placed
3630 If pending_flags was set in any thread, we queue any needed
3631 signals, since we won't actually resume. We already have a pending
3632 event to report, so we don't need to preserve any step requests;
3633 they should be re-issued if necessary. */
3636 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3638 struct lwp_info
*lwp
;
3639 struct thread_info
*thread
;
3641 int leave_all_stopped
= * (int *) arg
;
3644 thread
= (struct thread_info
*) entry
;
3645 lwp
= get_thread_lwp (thread
);
3647 if (lwp
->resume
== NULL
)
3650 if (lwp
->resume
->kind
== resume_stop
)
3653 fprintf (stderr
, "resume_stop request for LWP %ld\n", lwpid_of (lwp
));
3658 fprintf (stderr
, "stopping LWP %ld\n", lwpid_of (lwp
));
3660 /* Stop the thread, and wait for the event asynchronously,
3661 through the event loop. */
3667 fprintf (stderr
, "already stopped LWP %ld\n",
3670 /* The LWP may have been stopped in an internal event that
3671 was not meant to be notified back to GDB (e.g., gdbserver
3672 breakpoint), so we should be reporting a stop event in
3675 /* If the thread already has a pending SIGSTOP, this is a
3676 no-op. Otherwise, something later will presumably resume
3677 the thread and this will cause it to cancel any pending
3678 operation, due to last_resume_kind == resume_stop. If
3679 the thread already has a pending status to report, we
3680 will still report it the next time we wait - see
3681 status_pending_p_callback. */
3683 /* If we already have a pending signal to report, then
3684 there's no need to queue a SIGSTOP, as this means we're
3685 midway through moving the LWP out of the jumppad, and we
3686 will report the pending signal as soon as that is
3688 if (lwp
->pending_signals_to_report
== NULL
)
3692 /* For stop requests, we're done. */
3694 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3698 /* If this thread which is about to be resumed has a pending status,
3699 then don't resume any threads - we can just report the pending
3700 status. Make sure to queue any signals that would otherwise be
3701 sent. In all-stop mode, we do this decision based on if *any*
3702 thread has a pending status. If there's a thread that needs the
3703 step-over-breakpoint dance, then don't resume any other thread
3704 but that particular one. */
3705 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
3710 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
3712 step
= (lwp
->resume
->kind
== resume_step
);
3713 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
3718 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
3720 /* If we have a new signal, enqueue the signal. */
3721 if (lwp
->resume
->sig
!= 0)
3723 struct pending_signals
*p_sig
;
3724 p_sig
= xmalloc (sizeof (*p_sig
));
3725 p_sig
->prev
= lwp
->pending_signals
;
3726 p_sig
->signal
= lwp
->resume
->sig
;
3727 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3729 /* If this is the same signal we were previously stopped by,
3730 make sure to queue its siginfo. We can ignore the return
3731 value of ptrace; if it fails, we'll skip
3732 PTRACE_SETSIGINFO. */
3733 if (WIFSTOPPED (lwp
->last_status
)
3734 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
3735 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
3737 lwp
->pending_signals
= p_sig
;
3741 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3747 linux_resume (struct thread_resume
*resume_info
, size_t n
)
3749 struct thread_resume_array array
= { resume_info
, n
};
3750 struct lwp_info
*need_step_over
= NULL
;
3752 int leave_all_stopped
;
3754 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
3756 /* If there is a thread which would otherwise be resumed, which has
3757 a pending status, then don't resume any threads - we can just
3758 report the pending status. Make sure to queue any signals that
3759 would otherwise be sent. In non-stop mode, we'll apply this
3760 logic to each thread individually. We consume all pending events
3761 before considering to start a step-over (in all-stop). */
3764 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
3766 /* If there is a thread which would otherwise be resumed, which is
3767 stopped at a breakpoint that needs stepping over, then don't
3768 resume any threads - have it step over the breakpoint with all
3769 other threads stopped, then resume all threads again. Make sure
3770 to queue any signals that would otherwise be delivered or
3772 if (!any_pending
&& supports_breakpoints ())
3774 = (struct lwp_info
*) find_inferior (&all_lwps
,
3775 need_step_over_p
, NULL
);
3777 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
3781 if (need_step_over
!= NULL
)
3782 fprintf (stderr
, "Not resuming all, need step over\n");
3783 else if (any_pending
)
3785 "Not resuming, all-stop and found "
3786 "an LWP with pending status\n");
3788 fprintf (stderr
, "Resuming, no pending status or step over needed\n");
3791 /* Even if we're leaving threads stopped, queue all signals we'd
3792 otherwise deliver. */
3793 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
3796 start_step_over (need_step_over
);
3799 /* This function is called once per thread. We check the thread's
3800 last resume request, which will tell us whether to resume, step, or
3801 leave the thread stopped. Any signal the client requested to be
3802 delivered has already been enqueued at this point.
3804 If any thread that GDB wants running is stopped at an internal
3805 breakpoint that needs stepping over, we start a step-over operation
3806 on that particular thread, and leave all others stopped. */
3809 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3811 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3812 struct thread_info
*thread
;
3820 "proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
3825 fprintf (stderr
, " LWP %ld already running\n", lwpid_of (lwp
));
3829 thread
= get_lwp_thread (lwp
);
3831 if (thread
->last_resume_kind
== resume_stop
3832 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
3835 fprintf (stderr
, " client wants LWP to remain %ld stopped\n",
3840 if (lwp
->status_pending_p
)
3843 fprintf (stderr
, " LWP %ld has pending status, leaving stopped\n",
3848 gdb_assert (lwp
->suspended
>= 0);
3853 fprintf (stderr
, " LWP %ld is suspended\n", lwpid_of (lwp
));
3857 if (thread
->last_resume_kind
== resume_stop
3858 && lwp
->pending_signals_to_report
== NULL
3859 && lwp
->collecting_fast_tracepoint
== 0)
3861 /* We haven't reported this LWP as stopped yet (otherwise, the
3862 last_status.kind check above would catch it, and we wouldn't
3863 reach here. This LWP may have been momentarily paused by a
3864 stop_all_lwps call while handling for example, another LWP's
3865 step-over. In that case, the pending expected SIGSTOP signal
3866 that was queued at vCont;t handling time will have already
3867 been consumed by wait_for_sigstop, and so we need to requeue
3868 another one here. Note that if the LWP already has a SIGSTOP
3869 pending, this is a no-op. */
3873 "Client wants LWP %ld to stop. "
3874 "Making sure it has a SIGSTOP pending\n",
3880 step
= thread
->last_resume_kind
== resume_step
;
3881 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3886 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3888 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3894 gdb_assert (lwp
->suspended
>= 0);
3896 return proceed_one_lwp (entry
, except
);
3899 /* When we finish a step-over, set threads running again. If there's
3900 another thread that may need a step-over, now's the time to start
3901 it. Eventually, we'll move all threads past their breakpoints. */
3904 proceed_all_lwps (void)
3906 struct lwp_info
*need_step_over
;
3908 /* If there is a thread which would otherwise be resumed, which is
3909 stopped at a breakpoint that needs stepping over, then don't
3910 resume any threads - have it step over the breakpoint with all
3911 other threads stopped, then resume all threads again. */
3913 if (supports_breakpoints ())
3916 = (struct lwp_info
*) find_inferior (&all_lwps
,
3917 need_step_over_p
, NULL
);
3919 if (need_step_over
!= NULL
)
3922 fprintf (stderr
, "proceed_all_lwps: found "
3923 "thread %ld needing a step-over\n",
3924 lwpid_of (need_step_over
));
3926 start_step_over (need_step_over
);
3932 fprintf (stderr
, "Proceeding, no step-over needed\n");
3934 find_inferior (&all_lwps
, proceed_one_lwp
, NULL
);
3937 /* Stopped LWPs that the client wanted to be running, that don't have
3938 pending statuses, are set to run again, except for EXCEPT, if not
3939 NULL. This undoes a stop_all_lwps call. */
3942 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
3948 "unstopping all lwps, except=(LWP %ld)\n", lwpid_of (except
));
3951 "unstopping all lwps\n");
3955 find_inferior (&all_lwps
, unsuspend_and_proceed_one_lwp
, except
);
3957 find_inferior (&all_lwps
, proceed_one_lwp
, except
);
3961 #ifdef HAVE_LINUX_REGSETS
3963 #define use_linux_regsets 1
3966 regsets_fetch_inferior_registers (struct regcache
*regcache
)
3968 struct regset_info
*regset
;
3969 int saw_general_regs
= 0;
3973 regset
= target_regsets
;
3975 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3976 while (regset
->size
>= 0)
3981 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
3987 buf
= xmalloc (regset
->size
);
3989 nt_type
= regset
->nt_type
;
3993 iov
.iov_len
= regset
->size
;
3994 data
= (void *) &iov
;
4000 res
= ptrace (regset
->get_request
, pid
, nt_type
, data
);
4002 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4008 /* If we get EIO on a regset, do not try it again for
4010 disabled_regsets
[regset
- target_regsets
] = 1;
4017 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4022 else if (regset
->type
== GENERAL_REGS
)
4023 saw_general_regs
= 1;
4024 regset
->store_function (regcache
, buf
);
4028 if (saw_general_regs
)
4035 regsets_store_inferior_registers (struct regcache
*regcache
)
4037 struct regset_info
*regset
;
4038 int saw_general_regs
= 0;
4042 regset
= target_regsets
;
4044 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4045 while (regset
->size
>= 0)
4050 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
4056 buf
= xmalloc (regset
->size
);
4058 /* First fill the buffer with the current register set contents,
4059 in case there are any items in the kernel's regset that are
4060 not in gdbserver's regcache. */
4062 nt_type
= regset
->nt_type
;
4066 iov
.iov_len
= regset
->size
;
4067 data
= (void *) &iov
;
4073 res
= ptrace (regset
->get_request
, pid
, nt_type
, data
);
4075 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4080 /* Then overlay our cached registers on that. */
4081 regset
->fill_function (regcache
, buf
);
4083 /* Only now do we write the register set. */
4085 res
= ptrace (regset
->set_request
, pid
, nt_type
, data
);
4087 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4095 /* If we get EIO on a regset, do not try it again for
4097 disabled_regsets
[regset
- target_regsets
] = 1;
4101 else if (errno
== ESRCH
)
4103 /* At this point, ESRCH should mean the process is
4104 already gone, in which case we simply ignore attempts
4105 to change its registers. See also the related
4106 comment in linux_resume_one_lwp. */
4112 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4115 else if (regset
->type
== GENERAL_REGS
)
4116 saw_general_regs
= 1;
4120 if (saw_general_regs
)
4126 #else /* !HAVE_LINUX_REGSETS */
4128 #define use_linux_regsets 0
4129 #define regsets_fetch_inferior_registers(regcache) 1
4130 #define regsets_store_inferior_registers(regcache) 1
4134 /* Return 1 if register REGNO is supported by one of the regset ptrace
4135 calls or 0 if it has to be transferred individually. */
4138 linux_register_in_regsets (int regno
)
4140 unsigned char mask
= 1 << (regno
% 8);
4141 size_t index
= regno
/ 8;
4143 return (use_linux_regsets
4144 && (the_low_target
.regset_bitmap
== NULL
4145 || (the_low_target
.regset_bitmap
[index
] & mask
) != 0));
4148 #ifdef HAVE_LINUX_USRREGS
4151 register_addr (int regnum
)
4155 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
4156 error ("Invalid register number %d.", regnum
);
4158 addr
= the_low_target
.regmap
[regnum
];
4163 /* Fetch one register. */
4165 fetch_register (struct regcache
*regcache
, int regno
)
4172 if (regno
>= the_low_target
.num_regs
)
4174 if ((*the_low_target
.cannot_fetch_register
) (regno
))
4177 regaddr
= register_addr (regno
);
4181 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4182 & -sizeof (PTRACE_XFER_TYPE
));
4183 buf
= alloca (size
);
4185 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4186 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4189 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
4190 ptrace (PTRACE_PEEKUSER
, pid
,
4191 /* Coerce to a uintptr_t first to avoid potential gcc warning
4192 of coercing an 8 byte integer to a 4 byte pointer. */
4193 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
, 0);
4194 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4196 error ("reading register %d: %s", regno
, strerror (errno
));
4199 if (the_low_target
.supply_ptrace_register
)
4200 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
4202 supply_register (regcache
, regno
, buf
);
4205 /* Store one register. */
4207 store_register (struct regcache
*regcache
, int regno
)
4214 if (regno
>= the_low_target
.num_regs
)
4216 if ((*the_low_target
.cannot_store_register
) (regno
))
4219 regaddr
= register_addr (regno
);
4223 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4224 & -sizeof (PTRACE_XFER_TYPE
));
4225 buf
= alloca (size
);
4226 memset (buf
, 0, size
);
4228 if (the_low_target
.collect_ptrace_register
)
4229 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
4231 collect_register (regcache
, regno
, buf
);
4233 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4234 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4237 ptrace (PTRACE_POKEUSER
, pid
,
4238 /* Coerce to a uintptr_t first to avoid potential gcc warning
4239 about coercing an 8 byte integer to a 4 byte pointer. */
4240 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
,
4241 (PTRACE_ARG4_TYPE
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
4244 /* At this point, ESRCH should mean the process is
4245 already gone, in which case we simply ignore attempts
4246 to change its registers. See also the related
4247 comment in linux_resume_one_lwp. */
4251 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
4252 error ("writing register %d: %s", regno
, strerror (errno
));
4254 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4258 /* Fetch all registers, or just one, from the child process.
4259 If REGNO is -1, do this for all registers, skipping any that are
4260 assumed to have been retrieved by regsets_fetch_inferior_registers,
4261 unless ALL is non-zero.
4262 Otherwise, REGNO specifies which register (so we can save time). */
4264 usr_fetch_inferior_registers (struct regcache
*regcache
, int regno
, int all
)
4268 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4269 if (all
|| !linux_register_in_regsets (regno
))
4270 fetch_register (regcache
, regno
);
4273 fetch_register (regcache
, regno
);
4276 /* Store our register values back into the inferior.
4277 If REGNO is -1, do this for all registers, skipping any that are
4278 assumed to have been saved by regsets_store_inferior_registers,
4279 unless ALL is non-zero.
4280 Otherwise, REGNO specifies which register (so we can save time). */
4282 usr_store_inferior_registers (struct regcache
*regcache
, int regno
, int all
)
4286 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4287 if (all
|| !linux_register_in_regsets (regno
))
4288 store_register (regcache
, regno
);
4291 store_register (regcache
, regno
);
4294 #else /* !HAVE_LINUX_USRREGS */
4296 #define usr_fetch_inferior_registers(regcache, regno, all) do {} while (0)
4297 #define usr_store_inferior_registers(regcache, regno, all) do {} while (0)
4303 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4310 if (the_low_target
.fetch_register
!= NULL
)
4311 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4312 (*the_low_target
.fetch_register
) (regcache
, regno
);
4314 all
= regsets_fetch_inferior_registers (regcache
);
4315 usr_fetch_inferior_registers (regcache
, -1, all
);
4319 if (the_low_target
.fetch_register
!= NULL
4320 && (*the_low_target
.fetch_register
) (regcache
, regno
))
4323 use_regsets
= linux_register_in_regsets (regno
);
4325 all
= regsets_fetch_inferior_registers (regcache
);
4326 if (!use_regsets
|| all
)
4327 usr_fetch_inferior_registers (regcache
, regno
, 1);
4332 linux_store_registers (struct regcache
*regcache
, int regno
)
4339 all
= regsets_store_inferior_registers (regcache
);
4340 usr_store_inferior_registers (regcache
, regno
, all
);
4344 use_regsets
= linux_register_in_regsets (regno
);
4346 all
= regsets_store_inferior_registers (regcache
);
4347 if (!use_regsets
|| all
)
4348 usr_store_inferior_registers (regcache
, regno
, 1);
4353 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4354 to debugger memory starting at MYADDR. */
4357 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4360 /* Round starting address down to longword boundary. */
4361 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4362 /* Round ending address up; get number of longwords that makes. */
4364 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4365 / sizeof (PTRACE_XFER_TYPE
);
4366 /* Allocate buffer of that many longwords. */
4367 register PTRACE_XFER_TYPE
*buffer
4368 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4371 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4373 /* Try using /proc. Don't bother for one word. */
4374 if (len
>= 3 * sizeof (long))
4376 /* We could keep this file open and cache it - possibly one per
4377 thread. That requires some juggling, but is even faster. */
4378 sprintf (filename
, "/proc/%d/mem", pid
);
4379 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4383 /* If pread64 is available, use it. It's faster if the kernel
4384 supports it (only one syscall), and it's 64-bit safe even on
4385 32-bit platforms (for instance, SPARC debugging a SPARC64
4388 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
4390 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, myaddr
, len
) != len
)
4402 /* Read all the longwords */
4403 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4406 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4407 about coercing an 8 byte integer to a 4 byte pointer. */
4408 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4409 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4414 /* Copy appropriate bytes out of the buffer. */
4416 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4422 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4423 memory at MEMADDR. On failure (cannot write to the inferior)
4424 returns the value of errno. */
4427 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4430 /* Round starting address down to longword boundary. */
4431 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4432 /* Round ending address up; get number of longwords that makes. */
4434 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4435 / sizeof (PTRACE_XFER_TYPE
);
4437 /* Allocate buffer of that many longwords. */
4438 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4439 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4441 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4445 /* Dump up to four bytes. */
4446 unsigned int val
= * (unsigned int *) myaddr
;
4452 val
= val
& 0xffffff;
4453 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4454 val
, (long)memaddr
);
4457 /* Fill start and end extra bytes of buffer with existing memory data. */
4460 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4461 about coercing an 8 byte integer to a 4 byte pointer. */
4462 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4463 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4471 = ptrace (PTRACE_PEEKTEXT
, pid
,
4472 /* Coerce to a uintptr_t first to avoid potential gcc warning
4473 about coercing an 8 byte integer to a 4 byte pointer. */
4474 (PTRACE_ARG3_TYPE
) (uintptr_t) (addr
+ (count
- 1)
4475 * sizeof (PTRACE_XFER_TYPE
)),
4481 /* Copy data to be written over corresponding part of buffer. */
4483 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4486 /* Write the entire buffer. */
4488 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4491 ptrace (PTRACE_POKETEXT
, pid
,
4492 /* Coerce to a uintptr_t first to avoid potential gcc warning
4493 about coercing an 8 byte integer to a 4 byte pointer. */
4494 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
4495 (PTRACE_ARG4_TYPE
) buffer
[i
]);
4503 /* Non-zero if the kernel supports PTRACE_O_TRACEFORK. */
4504 static int linux_supports_tracefork_flag
;
4507 linux_enable_event_reporting (int pid
)
4509 if (!linux_supports_tracefork_flag
)
4512 ptrace (PTRACE_SETOPTIONS
, pid
, 0, (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
4515 /* Helper functions for linux_test_for_tracefork, called via clone (). */
4518 linux_tracefork_grandchild (void *arg
)
4523 #define STACK_SIZE 4096
4526 linux_tracefork_child (void *arg
)
4528 ptrace (PTRACE_TRACEME
, 0, 0, 0);
4529 kill (getpid (), SIGSTOP
);
4531 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4534 linux_tracefork_grandchild (NULL
);
4536 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4539 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
4540 CLONE_VM
| SIGCHLD
, NULL
);
4542 clone (linux_tracefork_grandchild
, (char *) arg
+ STACK_SIZE
,
4543 CLONE_VM
| SIGCHLD
, NULL
);
4546 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4551 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
4552 sure that we can enable the option, and that it had the desired
4556 linux_test_for_tracefork (void)
4558 int child_pid
, ret
, status
;
4560 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4561 char *stack
= xmalloc (STACK_SIZE
* 4);
4562 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4564 linux_supports_tracefork_flag
= 0;
4566 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4568 child_pid
= fork ();
4570 linux_tracefork_child (NULL
);
4572 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4574 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
4576 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
4577 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4578 #else /* !__ia64__ */
4579 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
4580 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4581 #endif /* !__ia64__ */
4583 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4585 if (child_pid
== -1)
4586 perror_with_name ("clone");
4588 ret
= my_waitpid (child_pid
, &status
, 0);
4590 perror_with_name ("waitpid");
4591 else if (ret
!= child_pid
)
4592 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
4593 if (! WIFSTOPPED (status
))
4594 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
4596 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
4597 (PTRACE_ARG4_TYPE
) PTRACE_O_TRACEFORK
);
4600 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4603 warning ("linux_test_for_tracefork: failed to kill child");
4607 ret
= my_waitpid (child_pid
, &status
, 0);
4608 if (ret
!= child_pid
)
4609 warning ("linux_test_for_tracefork: failed to wait for killed child");
4610 else if (!WIFSIGNALED (status
))
4611 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
4612 "killed child", status
);
4617 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
4619 warning ("linux_test_for_tracefork: failed to resume child");
4621 ret
= my_waitpid (child_pid
, &status
, 0);
4623 if (ret
== child_pid
&& WIFSTOPPED (status
)
4624 && status
>> 16 == PTRACE_EVENT_FORK
)
4627 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
4628 if (ret
== 0 && second_pid
!= 0)
4632 linux_supports_tracefork_flag
= 1;
4633 my_waitpid (second_pid
, &second_status
, 0);
4634 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
4636 warning ("linux_test_for_tracefork: failed to kill second child");
4637 my_waitpid (second_pid
, &status
, 0);
4641 warning ("linux_test_for_tracefork: unexpected result from waitpid "
4642 "(%d, status 0x%x)", ret
, status
);
4646 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4648 warning ("linux_test_for_tracefork: failed to kill child");
4649 my_waitpid (child_pid
, &status
, 0);
4651 while (WIFSTOPPED (status
));
4653 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4655 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4660 linux_look_up_symbols (void)
4662 #ifdef USE_THREAD_DB
4663 struct process_info
*proc
= current_process ();
4665 if (proc
->private->thread_db
!= NULL
)
4668 /* If the kernel supports tracing forks then it also supports tracing
4669 clones, and then we don't need to use the magic thread event breakpoint
4670 to learn about threads. */
4671 thread_db_init (!linux_supports_tracefork_flag
);
4676 linux_request_interrupt (void)
4678 extern unsigned long signal_pid
;
4680 if (!ptid_equal (cont_thread
, null_ptid
)
4681 && !ptid_equal (cont_thread
, minus_one_ptid
))
4683 struct lwp_info
*lwp
;
4686 lwp
= get_thread_lwp (current_inferior
);
4687 lwpid
= lwpid_of (lwp
);
4688 kill_lwp (lwpid
, SIGINT
);
4691 kill_lwp (signal_pid
, SIGINT
);
4694 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4695 to debugger memory starting at MYADDR. */
4698 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4700 char filename
[PATH_MAX
];
4702 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4704 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4706 fd
= open (filename
, O_RDONLY
);
4710 if (offset
!= (CORE_ADDR
) 0
4711 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4714 n
= read (fd
, myaddr
, len
);
4721 /* These breakpoint and watchpoint related wrapper functions simply
4722 pass on the function call if the target has registered a
4723 corresponding function. */
4726 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
4728 if (the_low_target
.insert_point
!= NULL
)
4729 return the_low_target
.insert_point (type
, addr
, len
);
4731 /* Unsupported (see target.h). */
4736 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
4738 if (the_low_target
.remove_point
!= NULL
)
4739 return the_low_target
.remove_point (type
, addr
, len
);
4741 /* Unsupported (see target.h). */
4746 linux_stopped_by_watchpoint (void)
4748 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4750 return lwp
->stopped_by_watchpoint
;
4754 linux_stopped_data_address (void)
4756 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4758 return lwp
->stopped_data_address
;
4761 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4762 #if defined(__mcoldfire__)
4763 /* These should really be defined in the kernel's ptrace.h header. */
4764 #define PT_TEXT_ADDR 49*4
4765 #define PT_DATA_ADDR 50*4
4766 #define PT_TEXT_END_ADDR 51*4
4768 #define PT_TEXT_ADDR 220
4769 #define PT_TEXT_END_ADDR 224
4770 #define PT_DATA_ADDR 228
4771 #elif defined(__TMS320C6X__)
4772 #define PT_TEXT_ADDR (0x10000*4)
4773 #define PT_DATA_ADDR (0x10004*4)
4774 #define PT_TEXT_END_ADDR (0x10008*4)
4777 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4778 to tell gdb about. */
4781 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
4783 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
4784 unsigned long text
, text_end
, data
;
4785 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4789 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
4790 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
4791 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
4795 /* Both text and data offsets produced at compile-time (and so
4796 used by gdb) are relative to the beginning of the program,
4797 with the data segment immediately following the text segment.
4798 However, the actual runtime layout in memory may put the data
4799 somewhere else, so when we send gdb a data base-address, we
4800 use the real data base address and subtract the compile-time
4801 data base-address from it (which is just the length of the
4802 text segment). BSS immediately follows data in both
4805 *data_p
= data
- (text_end
- text
);
4815 linux_qxfer_osdata (const char *annex
,
4816 unsigned char *readbuf
, unsigned const char *writebuf
,
4817 CORE_ADDR offset
, int len
)
4819 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
4822 /* Convert a native/host siginfo object, into/from the siginfo in the
4823 layout of the inferiors' architecture. */
4826 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
4830 if (the_low_target
.siginfo_fixup
!= NULL
)
4831 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4833 /* If there was no callback, or the callback didn't do anything,
4834 then just do a straight memcpy. */
4838 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
4840 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
4845 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
4846 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
4850 char inf_siginfo
[sizeof (siginfo_t
)];
4852 if (current_inferior
== NULL
)
4855 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4858 fprintf (stderr
, "%s siginfo for lwp %d.\n",
4859 readbuf
!= NULL
? "Reading" : "Writing",
4862 if (offset
>= sizeof (siginfo
))
4865 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
4868 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4869 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4870 inferior with a 64-bit GDBSERVER should look the same as debugging it
4871 with a 32-bit GDBSERVER, we need to convert it. */
4872 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4874 if (offset
+ len
> sizeof (siginfo
))
4875 len
= sizeof (siginfo
) - offset
;
4877 if (readbuf
!= NULL
)
4878 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4881 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4883 /* Convert back to ptrace layout before flushing it out. */
4884 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4886 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
4893 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4894 so we notice when children change state; as the handler for the
4895 sigsuspend in my_waitpid. */
4898 sigchld_handler (int signo
)
4900 int old_errno
= errno
;
4906 /* fprintf is not async-signal-safe, so call write
4908 if (write (2, "sigchld_handler\n",
4909 sizeof ("sigchld_handler\n") - 1) < 0)
4910 break; /* just ignore */
4914 if (target_is_async_p ())
4915 async_file_mark (); /* trigger a linux_wait */
4921 linux_supports_non_stop (void)
4927 linux_async (int enable
)
4929 int previous
= (linux_event_pipe
[0] != -1);
4932 fprintf (stderr
, "linux_async (%d), previous=%d\n",
4935 if (previous
!= enable
)
4938 sigemptyset (&mask
);
4939 sigaddset (&mask
, SIGCHLD
);
4941 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
4945 if (pipe (linux_event_pipe
) == -1)
4946 fatal ("creating event pipe failed.");
4948 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
4949 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
4951 /* Register the event loop handler. */
4952 add_file_handler (linux_event_pipe
[0],
4953 handle_target_event
, NULL
);
4955 /* Always trigger a linux_wait. */
4960 delete_file_handler (linux_event_pipe
[0]);
4962 close (linux_event_pipe
[0]);
4963 close (linux_event_pipe
[1]);
4964 linux_event_pipe
[0] = -1;
4965 linux_event_pipe
[1] = -1;
4968 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
4975 linux_start_non_stop (int nonstop
)
4977 /* Register or unregister from event-loop accordingly. */
4978 linux_async (nonstop
);
4983 linux_supports_multi_process (void)
4989 linux_supports_disable_randomization (void)
4991 #ifdef HAVE_PERSONALITY
4999 linux_supports_agent (void)
5004 /* Enumerate spufs IDs for process PID. */
5006 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
5012 struct dirent
*entry
;
5014 sprintf (path
, "/proc/%ld/fd", pid
);
5015 dir
= opendir (path
);
5020 while ((entry
= readdir (dir
)) != NULL
)
5026 fd
= atoi (entry
->d_name
);
5030 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
5031 if (stat (path
, &st
) != 0)
5033 if (!S_ISDIR (st
.st_mode
))
5036 if (statfs (path
, &stfs
) != 0)
5038 if (stfs
.f_type
!= SPUFS_MAGIC
)
5041 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
5043 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
5053 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
5054 object type, using the /proc file system. */
5056 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
5057 unsigned const char *writebuf
,
5058 CORE_ADDR offset
, int len
)
5060 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
5065 if (!writebuf
&& !readbuf
)
5073 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5076 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
5077 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5082 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5089 ret
= write (fd
, writebuf
, (size_t) len
);
5091 ret
= read (fd
, readbuf
, (size_t) len
);
5097 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5098 struct target_loadseg
5100 /* Core address to which the segment is mapped. */
5102 /* VMA recorded in the program header. */
5104 /* Size of this segment in memory. */
5108 # if defined PT_GETDSBT
5109 struct target_loadmap
5111 /* Protocol version number, must be zero. */
5113 /* Pointer to the DSBT table, its size, and the DSBT index. */
5114 unsigned *dsbt_table
;
5115 unsigned dsbt_size
, dsbt_index
;
5116 /* Number of segments in this map. */
5118 /* The actual memory map. */
5119 struct target_loadseg segs
[/*nsegs*/];
5121 # define LINUX_LOADMAP PT_GETDSBT
5122 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5123 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5125 struct target_loadmap
5127 /* Protocol version number, must be zero. */
5129 /* Number of segments in this map. */
5131 /* The actual memory map. */
5132 struct target_loadseg segs
[/*nsegs*/];
5134 # define LINUX_LOADMAP PTRACE_GETFDPIC
5135 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5136 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5140 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
5141 unsigned char *myaddr
, unsigned int len
)
5143 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
5145 struct target_loadmap
*data
= NULL
;
5146 unsigned int actual_length
, copy_length
;
5148 if (strcmp (annex
, "exec") == 0)
5149 addr
= (int) LINUX_LOADMAP_EXEC
;
5150 else if (strcmp (annex
, "interp") == 0)
5151 addr
= (int) LINUX_LOADMAP_INTERP
;
5155 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
5161 actual_length
= sizeof (struct target_loadmap
)
5162 + sizeof (struct target_loadseg
) * data
->nsegs
;
5164 if (offset
< 0 || offset
> actual_length
)
5167 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
5168 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
5172 # define linux_read_loadmap NULL
5173 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5176 linux_process_qsupported (const char *query
)
5178 if (the_low_target
.process_qsupported
!= NULL
)
5179 the_low_target
.process_qsupported (query
);
5183 linux_supports_tracepoints (void)
5185 if (*the_low_target
.supports_tracepoints
== NULL
)
5188 return (*the_low_target
.supports_tracepoints
) ();
5192 linux_read_pc (struct regcache
*regcache
)
5194 if (the_low_target
.get_pc
== NULL
)
5197 return (*the_low_target
.get_pc
) (regcache
);
5201 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
5203 gdb_assert (the_low_target
.set_pc
!= NULL
);
5205 (*the_low_target
.set_pc
) (regcache
, pc
);
5209 linux_thread_stopped (struct thread_info
*thread
)
5211 return get_thread_lwp (thread
)->stopped
;
5214 /* This exposes stop-all-threads functionality to other modules. */
5217 linux_pause_all (int freeze
)
5219 stop_all_lwps (freeze
, NULL
);
5222 /* This exposes unstop-all-threads functionality to other gdbserver
5226 linux_unpause_all (int unfreeze
)
5228 unstop_all_lwps (unfreeze
, NULL
);
5232 linux_prepare_to_access_memory (void)
5234 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5237 linux_pause_all (1);
5242 linux_done_accessing_memory (void)
5244 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5247 linux_unpause_all (1);
5251 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5252 CORE_ADDR collector
,
5255 CORE_ADDR
*jump_entry
,
5256 CORE_ADDR
*trampoline
,
5257 ULONGEST
*trampoline_size
,
5258 unsigned char *jjump_pad_insn
,
5259 ULONGEST
*jjump_pad_insn_size
,
5260 CORE_ADDR
*adjusted_insn_addr
,
5261 CORE_ADDR
*adjusted_insn_addr_end
,
5264 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5265 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5266 jump_entry
, trampoline
, trampoline_size
,
5267 jjump_pad_insn
, jjump_pad_insn_size
,
5268 adjusted_insn_addr
, adjusted_insn_addr_end
,
5272 static struct emit_ops
*
5273 linux_emit_ops (void)
5275 if (the_low_target
.emit_ops
!= NULL
)
5276 return (*the_low_target
.emit_ops
) ();
5282 linux_get_min_fast_tracepoint_insn_len (void)
5284 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5287 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5290 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5291 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5293 char filename
[PATH_MAX
];
5295 const int auxv_size
= is_elf64
5296 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5297 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5299 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5301 fd
= open (filename
, O_RDONLY
);
5307 while (read (fd
, buf
, auxv_size
) == auxv_size
5308 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5312 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5314 switch (aux
->a_type
)
5317 *phdr_memaddr
= aux
->a_un
.a_val
;
5320 *num_phdr
= aux
->a_un
.a_val
;
5326 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5328 switch (aux
->a_type
)
5331 *phdr_memaddr
= aux
->a_un
.a_val
;
5334 *num_phdr
= aux
->a_un
.a_val
;
5342 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5344 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5345 "phdr_memaddr = %ld, phdr_num = %d",
5346 (long) *phdr_memaddr
, *num_phdr
);
5353 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5356 get_dynamic (const int pid
, const int is_elf64
)
5358 CORE_ADDR phdr_memaddr
, relocation
;
5360 unsigned char *phdr_buf
;
5361 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5363 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5366 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5367 phdr_buf
= alloca (num_phdr
* phdr_size
);
5369 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5372 /* Compute relocation: it is expected to be 0 for "regular" executables,
5373 non-zero for PIE ones. */
5375 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5378 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5380 if (p
->p_type
== PT_PHDR
)
5381 relocation
= phdr_memaddr
- p
->p_vaddr
;
5385 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5387 if (p
->p_type
== PT_PHDR
)
5388 relocation
= phdr_memaddr
- p
->p_vaddr
;
5391 if (relocation
== -1)
5393 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5394 any real world executables, including PIE executables, have always
5395 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5396 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5397 or present DT_DEBUG anyway (fpc binaries are statically linked).
5399 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5401 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5406 for (i
= 0; i
< num_phdr
; i
++)
5410 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5412 if (p
->p_type
== PT_DYNAMIC
)
5413 return p
->p_vaddr
+ relocation
;
5417 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5419 if (p
->p_type
== PT_DYNAMIC
)
5420 return p
->p_vaddr
+ relocation
;
5427 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5428 can be 0 if the inferior does not yet have the library list initialized.
5429 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
5430 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
5433 get_r_debug (const int pid
, const int is_elf64
)
5435 CORE_ADDR dynamic_memaddr
;
5436 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5437 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5440 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5441 if (dynamic_memaddr
== 0)
5444 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5448 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5452 unsigned char buf
[sizeof (Elf64_Xword
)];
5456 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5458 if (linux_read_memory (dyn
->d_un
.d_val
,
5459 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5465 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5466 map
= dyn
->d_un
.d_val
;
5468 if (dyn
->d_tag
== DT_NULL
)
5473 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5477 unsigned char buf
[sizeof (Elf32_Word
)];
5481 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5483 if (linux_read_memory (dyn
->d_un
.d_val
,
5484 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5490 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5491 map
= dyn
->d_un
.d_val
;
5493 if (dyn
->d_tag
== DT_NULL
)
5497 dynamic_memaddr
+= dyn_size
;
5503 /* Read one pointer from MEMADDR in the inferior. */
5506 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5510 /* Go through a union so this works on either big or little endian
5511 hosts, when the inferior's pointer size is smaller than the size
5512 of CORE_ADDR. It is assumed the inferior's endianness is the
5513 same of the superior's. */
5516 CORE_ADDR core_addr
;
5521 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
5524 if (ptr_size
== sizeof (CORE_ADDR
))
5525 *ptr
= addr
.core_addr
;
5526 else if (ptr_size
== sizeof (unsigned int))
5529 gdb_assert_not_reached ("unhandled pointer size");
5534 struct link_map_offsets
5536 /* Offset and size of r_debug.r_version. */
5537 int r_version_offset
;
5539 /* Offset and size of r_debug.r_map. */
5542 /* Offset to l_addr field in struct link_map. */
5545 /* Offset to l_name field in struct link_map. */
5548 /* Offset to l_ld field in struct link_map. */
5551 /* Offset to l_next field in struct link_map. */
5554 /* Offset to l_prev field in struct link_map. */
5558 /* Construct qXfer:libraries-svr4:read reply. */
5561 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5562 unsigned const char *writebuf
,
5563 CORE_ADDR offset
, int len
)
5566 unsigned document_len
;
5567 struct process_info_private
*const priv
= current_process ()->private;
5568 char filename
[PATH_MAX
];
5571 static const struct link_map_offsets lmo_32bit_offsets
=
5573 0, /* r_version offset. */
5574 4, /* r_debug.r_map offset. */
5575 0, /* l_addr offset in link_map. */
5576 4, /* l_name offset in link_map. */
5577 8, /* l_ld offset in link_map. */
5578 12, /* l_next offset in link_map. */
5579 16 /* l_prev offset in link_map. */
5582 static const struct link_map_offsets lmo_64bit_offsets
=
5584 0, /* r_version offset. */
5585 8, /* r_debug.r_map offset. */
5586 0, /* l_addr offset in link_map. */
5587 8, /* l_name offset in link_map. */
5588 16, /* l_ld offset in link_map. */
5589 24, /* l_next offset in link_map. */
5590 32 /* l_prev offset in link_map. */
5592 const struct link_map_offsets
*lmo
;
5593 unsigned int machine
;
5595 if (writebuf
!= NULL
)
5597 if (readbuf
== NULL
)
5600 pid
= lwpid_of (get_thread_lwp (current_inferior
));
5601 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5602 is_elf64
= elf_64_file_p (filename
, &machine
);
5603 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5605 if (priv
->r_debug
== 0)
5606 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5608 if (priv
->r_debug
== (CORE_ADDR
) -1 || priv
->r_debug
== 0)
5610 document
= xstrdup ("<library-list-svr4 version=\"1.0\"/>\n");
5614 int allocated
= 1024;
5616 const int ptr_size
= is_elf64
? 8 : 4;
5617 CORE_ADDR lm_addr
, lm_prev
, l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5618 int r_version
, header_done
= 0;
5620 document
= xmalloc (allocated
);
5621 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5622 p
= document
+ strlen (document
);
5625 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5626 (unsigned char *) &r_version
,
5627 sizeof (r_version
)) != 0
5630 warning ("unexpected r_debug version %d", r_version
);
5634 if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5635 &lm_addr
, ptr_size
) != 0)
5637 warning ("unable to read r_map from 0x%lx",
5638 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5643 while (read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5644 &l_name
, ptr_size
) == 0
5645 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5646 &l_addr
, ptr_size
) == 0
5647 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5648 &l_ld
, ptr_size
) == 0
5649 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5650 &l_prev
, ptr_size
) == 0
5651 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5652 &l_next
, ptr_size
) == 0)
5654 unsigned char libname
[PATH_MAX
];
5656 if (lm_prev
!= l_prev
)
5658 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5659 (long) lm_prev
, (long) l_prev
);
5663 /* Not checking for error because reading may stop before
5664 we've got PATH_MAX worth of characters. */
5666 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5667 libname
[sizeof (libname
) - 1] = '\0';
5668 if (libname
[0] != '\0')
5670 /* 6x the size for xml_escape_text below. */
5671 size_t len
= 6 * strlen ((char *) libname
);
5676 /* Terminate `<library-list-svr4'. */
5681 while (allocated
< p
- document
+ len
+ 200)
5683 /* Expand to guarantee sufficient storage. */
5684 uintptr_t document_len
= p
- document
;
5686 document
= xrealloc (document
, 2 * allocated
);
5688 p
= document
+ document_len
;
5691 name
= xml_escape_text ((char *) libname
);
5692 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
5693 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5694 name
, (unsigned long) lm_addr
,
5695 (unsigned long) l_addr
, (unsigned long) l_ld
);
5698 else if (lm_prev
== 0)
5700 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5713 /* Empty list; terminate `<library-list-svr4'. */
5717 strcpy (p
, "</library-list-svr4>");
5720 document_len
= strlen (document
);
5721 if (offset
< document_len
)
5722 document_len
-= offset
;
5725 if (len
> document_len
)
5728 memcpy (readbuf
, document
+ offset
, len
);
5734 static struct target_ops linux_target_ops
= {
5735 linux_create_inferior
,
5744 linux_fetch_registers
,
5745 linux_store_registers
,
5746 linux_prepare_to_access_memory
,
5747 linux_done_accessing_memory
,
5750 linux_look_up_symbols
,
5751 linux_request_interrupt
,
5755 linux_stopped_by_watchpoint
,
5756 linux_stopped_data_address
,
5757 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
5762 #ifdef USE_THREAD_DB
5763 thread_db_get_tls_address
,
5768 hostio_last_error_from_errno
,
5771 linux_supports_non_stop
,
5773 linux_start_non_stop
,
5774 linux_supports_multi_process
,
5775 #ifdef USE_THREAD_DB
5776 thread_db_handle_monitor_command
,
5780 linux_common_core_of_thread
,
5782 linux_process_qsupported
,
5783 linux_supports_tracepoints
,
5786 linux_thread_stopped
,
5790 linux_cancel_breakpoints
,
5791 linux_stabilize_threads
,
5792 linux_install_fast_tracepoint_jump_pad
,
5794 linux_supports_disable_randomization
,
5795 linux_get_min_fast_tracepoint_insn_len
,
5796 linux_qxfer_libraries_svr4
,
5797 linux_supports_agent
,
5801 linux_init_signals ()
5803 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5804 to find what the cancel signal actually is. */
5805 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
5806 signal (__SIGRTMIN
+1, SIG_IGN
);
5811 initialize_low (void)
5813 struct sigaction sigchld_action
;
5814 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
5815 set_target_ops (&linux_target_ops
);
5816 set_breakpoint_data (the_low_target
.breakpoint
,
5817 the_low_target
.breakpoint_len
);
5818 linux_init_signals ();
5819 linux_test_for_tracefork ();
5820 #ifdef HAVE_LINUX_REGSETS
5821 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
5823 disabled_regsets
= xmalloc (num_regsets
);
5826 sigchld_action
.sa_handler
= sigchld_handler
;
5827 sigemptyset (&sigchld_action
.sa_mask
);
5828 sigchld_action
.sa_flags
= SA_RESTART
;
5829 sigaction (SIGCHLD
, &sigchld_action
, NULL
);