1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2013 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__))
81 /* PTRACE_TEXT_ADDR and friends. */
82 #include <asm/ptrace.h>
87 #ifdef HAVE_LINUX_BTRACE
88 # include "linux-btrace.h"
91 #ifndef HAVE_ELF32_AUXV_T
92 /* Copied from glibc's elf.h. */
95 uint32_t a_type
; /* Entry type */
98 uint32_t a_val
; /* Integer value */
99 /* We use to have pointer elements added here. We cannot do that,
100 though, since it does not work when using 32-bit definitions
101 on 64-bit platforms and vice versa. */
106 #ifndef HAVE_ELF64_AUXV_T
107 /* Copied from glibc's elf.h. */
110 uint64_t a_type
; /* Entry type */
113 uint64_t a_val
; /* Integer value */
114 /* We use to have pointer elements added here. We cannot do that,
115 though, since it does not work when using 32-bit definitions
116 on 64-bit platforms and vice versa. */
121 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
122 representation of the thread ID.
124 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
125 the same as the LWP ID.
127 ``all_processes'' is keyed by the "overall process ID", which
128 GNU/Linux calls tgid, "thread group ID". */
130 struct inferior_list all_lwps
;
132 /* A list of all unknown processes which receive stop signals. Some
133 other process will presumably claim each of these as forked
134 children momentarily. */
136 struct simple_pid_list
138 /* The process ID. */
141 /* The status as reported by waitpid. */
145 struct simple_pid_list
*next
;
147 struct simple_pid_list
*stopped_pids
;
149 /* Trivial list manipulation functions to keep track of a list of new
150 stopped processes. */
153 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
155 struct simple_pid_list
*new_pid
= xmalloc (sizeof (struct simple_pid_list
));
158 new_pid
->status
= status
;
159 new_pid
->next
= *listp
;
164 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
166 struct simple_pid_list
**p
;
168 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
169 if ((*p
)->pid
== pid
)
171 struct simple_pid_list
*next
= (*p
)->next
;
173 *statusp
= (*p
)->status
;
181 enum stopping_threads_kind
183 /* Not stopping threads presently. */
184 NOT_STOPPING_THREADS
,
186 /* Stopping threads. */
189 /* Stopping and suspending threads. */
190 STOPPING_AND_SUSPENDING_THREADS
193 /* This is set while stop_all_lwps is in effect. */
194 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
196 /* FIXME make into a target method? */
197 int using_threads
= 1;
199 /* True if we're presently stabilizing threads (moving them out of
201 static int stabilizing_threads
;
203 /* This flag is true iff we've just created or attached to our first
204 inferior but it has not stopped yet. As soon as it does, we need
205 to call the low target's arch_setup callback. Doing this only on
206 the first inferior avoids reinializing the architecture on every
207 inferior, and avoids messing with the register caches of the
208 already running inferiors. NOTE: this assumes all inferiors under
209 control of gdbserver have the same architecture. */
210 static int new_inferior
;
212 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
213 int step
, int signal
, siginfo_t
*info
);
214 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
215 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
216 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
217 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
218 static void *add_lwp (ptid_t ptid
);
219 static int linux_stopped_by_watchpoint (void);
220 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
221 static void proceed_all_lwps (void);
222 static int finish_step_over (struct lwp_info
*lwp
);
223 static CORE_ADDR
get_stop_pc (struct lwp_info
*lwp
);
224 static int kill_lwp (unsigned long lwpid
, int signo
);
225 static void linux_enable_event_reporting (int pid
);
227 /* True if the low target can hardware single-step. Such targets
228 don't need a BREAKPOINT_REINSERT_ADDR callback. */
231 can_hardware_single_step (void)
233 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
236 /* True if the low target supports memory breakpoints. If so, we'll
237 have a GET_PC implementation. */
240 supports_breakpoints (void)
242 return (the_low_target
.get_pc
!= NULL
);
245 /* Returns true if this target can support fast tracepoints. This
246 does not mean that the in-process agent has been loaded in the
250 supports_fast_tracepoints (void)
252 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
255 struct pending_signals
259 struct pending_signals
*prev
;
262 #ifdef HAVE_LINUX_REGSETS
263 static char *disabled_regsets
;
264 static int num_regsets
;
267 /* The read/write ends of the pipe registered as waitable file in the
269 static int linux_event_pipe
[2] = { -1, -1 };
271 /* True if we're currently in async mode. */
272 #define target_is_async_p() (linux_event_pipe[0] != -1)
274 static void send_sigstop (struct lwp_info
*lwp
);
275 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
277 /* Return non-zero if HEADER is a 64-bit ELF file. */
280 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
282 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
283 && header
->e_ident
[EI_MAG1
] == ELFMAG1
284 && header
->e_ident
[EI_MAG2
] == ELFMAG2
285 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
287 *machine
= header
->e_machine
;
288 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
295 /* Return non-zero if FILE is a 64-bit ELF file,
296 zero if the file is not a 64-bit ELF file,
297 and -1 if the file is not accessible or doesn't exist. */
300 elf_64_file_p (const char *file
, unsigned int *machine
)
305 fd
= open (file
, O_RDONLY
);
309 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
316 return elf_64_header_p (&header
, machine
);
319 /* Accepts an integer PID; Returns true if the executable PID is
320 running is a 64-bit ELF file.. */
323 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
325 char file
[MAXPATHLEN
];
327 sprintf (file
, "/proc/%d/exe", pid
);
328 return elf_64_file_p (file
, machine
);
332 delete_lwp (struct lwp_info
*lwp
)
334 remove_thread (get_lwp_thread (lwp
));
335 remove_inferior (&all_lwps
, &lwp
->head
);
336 free (lwp
->arch_private
);
340 /* Add a process to the common process list, and set its private
343 static struct process_info
*
344 linux_add_process (int pid
, int attached
)
346 struct process_info
*proc
;
348 /* Is this the first process? If so, then set the arch. */
349 if (all_processes
.head
== NULL
)
352 proc
= add_process (pid
, attached
);
353 proc
->private = xcalloc (1, sizeof (*proc
->private));
355 if (the_low_target
.new_process
!= NULL
)
356 proc
->private->arch_private
= the_low_target
.new_process ();
361 /* Wrapper function for waitpid which handles EINTR, and emulates
362 __WALL for systems where that is not available. */
365 my_waitpid (int pid
, int *status
, int flags
)
370 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
374 sigset_t block_mask
, org_mask
, wake_mask
;
377 wnohang
= (flags
& WNOHANG
) != 0;
378 flags
&= ~(__WALL
| __WCLONE
);
381 /* Block all signals while here. This avoids knowing about
382 LinuxThread's signals. */
383 sigfillset (&block_mask
);
384 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
386 /* ... except during the sigsuspend below. */
387 sigemptyset (&wake_mask
);
391 /* Since all signals are blocked, there's no need to check
393 ret
= waitpid (pid
, status
, flags
);
396 if (ret
== -1 && out_errno
!= ECHILD
)
401 if (flags
& __WCLONE
)
403 /* We've tried both flavors now. If WNOHANG is set,
404 there's nothing else to do, just bail out. */
409 fprintf (stderr
, "blocking\n");
411 /* Block waiting for signals. */
412 sigsuspend (&wake_mask
);
418 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
423 ret
= waitpid (pid
, status
, flags
);
424 while (ret
== -1 && errno
== EINTR
);
429 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
430 pid
, flags
, status
? *status
: -1, ret
);
436 /* Handle a GNU/Linux extended wait response. If we see a clone
437 event, we need to add the new LWP to our list (and not report the
438 trap to higher layers). */
441 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
443 int event
= wstat
>> 16;
444 struct lwp_info
*new_lwp
;
446 if (event
== PTRACE_EVENT_CLONE
)
449 unsigned long new_pid
;
452 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), (PTRACE_ARG3_TYPE
) 0,
455 /* If we haven't already seen the new PID stop, wait for it now. */
456 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
458 /* The new child has a pending SIGSTOP. We can't affect it until it
459 hits the SIGSTOP, but we're already attached. */
461 ret
= my_waitpid (new_pid
, &status
, __WALL
);
464 perror_with_name ("waiting for new child");
465 else if (ret
!= new_pid
)
466 warning ("wait returned unexpected PID %d", ret
);
467 else if (!WIFSTOPPED (status
))
468 warning ("wait returned unexpected status 0x%x", status
);
471 linux_enable_event_reporting (new_pid
);
473 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
474 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
475 add_thread (ptid
, new_lwp
);
477 /* Either we're going to immediately resume the new thread
478 or leave it stopped. linux_resume_one_lwp is a nop if it
479 thinks the thread is currently running, so set this first
480 before calling linux_resume_one_lwp. */
481 new_lwp
->stopped
= 1;
483 /* If we're suspending all threads, leave this one suspended
485 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
486 new_lwp
->suspended
= 1;
488 /* Normally we will get the pending SIGSTOP. But in some cases
489 we might get another signal delivered to the group first.
490 If we do get another signal, be sure not to lose it. */
491 if (WSTOPSIG (status
) == SIGSTOP
)
493 if (stopping_threads
!= NOT_STOPPING_THREADS
)
494 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
496 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
500 new_lwp
->stop_expected
= 1;
502 if (stopping_threads
!= NOT_STOPPING_THREADS
)
504 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
505 new_lwp
->status_pending_p
= 1;
506 new_lwp
->status_pending
= status
;
509 /* Pass the signal on. This is what GDB does - except
510 shouldn't we really report it instead? */
511 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
514 /* Always resume the current thread. If we are stopping
515 threads, it will have a pending SIGSTOP; we may as well
517 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
521 /* Return the PC as read from the regcache of LWP, without any
525 get_pc (struct lwp_info
*lwp
)
527 struct thread_info
*saved_inferior
;
528 struct regcache
*regcache
;
531 if (the_low_target
.get_pc
== NULL
)
534 saved_inferior
= current_inferior
;
535 current_inferior
= get_lwp_thread (lwp
);
537 regcache
= get_thread_regcache (current_inferior
, 1);
538 pc
= (*the_low_target
.get_pc
) (regcache
);
541 fprintf (stderr
, "pc is 0x%lx\n", (long) pc
);
543 current_inferior
= saved_inferior
;
547 /* This function should only be called if LWP got a SIGTRAP.
548 The SIGTRAP could mean several things.
550 On i386, where decr_pc_after_break is non-zero:
551 If we were single-stepping this process using PTRACE_SINGLESTEP,
552 we will get only the one SIGTRAP (even if the instruction we
553 stepped over was a breakpoint). The value of $eip will be the
555 If we continue the process using PTRACE_CONT, we will get a
556 SIGTRAP when we hit a breakpoint. The value of $eip will be
557 the instruction after the breakpoint (i.e. needs to be
558 decremented). If we report the SIGTRAP to GDB, we must also
559 report the undecremented PC. If we cancel the SIGTRAP, we
560 must resume at the decremented PC.
562 (Presumably, not yet tested) On a non-decr_pc_after_break machine
563 with hardware or kernel single-step:
564 If we single-step over a breakpoint instruction, our PC will
565 point at the following instruction. If we continue and hit a
566 breakpoint instruction, our PC will point at the breakpoint
570 get_stop_pc (struct lwp_info
*lwp
)
574 if (the_low_target
.get_pc
== NULL
)
577 stop_pc
= get_pc (lwp
);
579 if (WSTOPSIG (lwp
->last_status
) == SIGTRAP
581 && !lwp
->stopped_by_watchpoint
582 && lwp
->last_status
>> 16 == 0)
583 stop_pc
-= the_low_target
.decr_pc_after_break
;
586 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
592 add_lwp (ptid_t ptid
)
594 struct lwp_info
*lwp
;
596 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
597 memset (lwp
, 0, sizeof (*lwp
));
601 if (the_low_target
.new_thread
!= NULL
)
602 lwp
->arch_private
= the_low_target
.new_thread ();
604 add_inferior_to_list (&all_lwps
, &lwp
->head
);
609 /* Start an inferior process and returns its pid.
610 ALLARGS is a vector of program-name and args. */
613 linux_create_inferior (char *program
, char **allargs
)
615 #ifdef HAVE_PERSONALITY
616 int personality_orig
= 0, personality_set
= 0;
618 struct lwp_info
*new_lwp
;
622 #ifdef HAVE_PERSONALITY
623 if (disable_randomization
)
626 personality_orig
= personality (0xffffffff);
627 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
630 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
632 if (errno
!= 0 || (personality_set
633 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
634 warning ("Error disabling address space randomization: %s",
639 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
645 perror_with_name ("fork");
649 ptrace (PTRACE_TRACEME
, 0, (PTRACE_ARG3_TYPE
) 0, (PTRACE_ARG4_TYPE
) 0);
651 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
652 signal (__SIGRTMIN
+ 1, SIG_DFL
);
657 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
658 stdout to stderr so that inferior i/o doesn't corrupt the connection.
659 Also, redirect stdin to /dev/null. */
660 if (remote_connection_is_stdio ())
663 open ("/dev/null", O_RDONLY
);
665 if (write (2, "stdin/stdout redirected\n",
666 sizeof ("stdin/stdout redirected\n") - 1) < 0)
668 /* Errors ignored. */;
672 execv (program
, allargs
);
674 execvp (program
, allargs
);
676 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
682 #ifdef HAVE_PERSONALITY
686 personality (personality_orig
);
688 warning ("Error restoring address space randomization: %s",
693 linux_add_process (pid
, 0);
695 ptid
= ptid_build (pid
, pid
, 0);
696 new_lwp
= add_lwp (ptid
);
697 add_thread (ptid
, new_lwp
);
698 new_lwp
->must_set_ptrace_flags
= 1;
703 /* Attach to an inferior process. */
706 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
709 struct lwp_info
*new_lwp
;
711 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_ARG3_TYPE
) 0, (PTRACE_ARG4_TYPE
) 0)
714 struct buffer buffer
;
718 /* If we fail to attach to an LWP, just warn. */
719 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
720 strerror (errno
), errno
);
725 /* If we fail to attach to a process, report an error. */
726 buffer_init (&buffer
);
727 linux_ptrace_attach_warnings (lwpid
, &buffer
);
728 buffer_grow_str0 (&buffer
, "");
729 error ("%sCannot attach to lwp %ld: %s (%d)", buffer_finish (&buffer
),
730 lwpid
, strerror (errno
), errno
);
734 /* If lwp is the tgid, we handle adding existing threads later.
735 Otherwise we just add lwp without bothering about any other
737 ptid
= ptid_build (lwpid
, lwpid
, 0);
740 /* Note that extracting the pid from the current inferior is
741 safe, since we're always called in the context of the same
742 process as this new thread. */
743 int pid
= pid_of (get_thread_lwp (current_inferior
));
744 ptid
= ptid_build (pid
, lwpid
, 0);
747 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
748 add_thread (ptid
, new_lwp
);
750 /* We need to wait for SIGSTOP before being able to make the next
751 ptrace call on this LWP. */
752 new_lwp
->must_set_ptrace_flags
= 1;
754 if (linux_proc_pid_is_stopped (lwpid
))
758 "Attached to a stopped process\n");
760 /* The process is definitely stopped. It is in a job control
761 stop, unless the kernel predates the TASK_STOPPED /
762 TASK_TRACED distinction, in which case it might be in a
763 ptrace stop. Make sure it is in a ptrace stop; from there we
764 can kill it, signal it, et cetera.
766 First make sure there is a pending SIGSTOP. Since we are
767 already attached, the process can not transition from stopped
768 to running without a PTRACE_CONT; so we know this signal will
769 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
770 probably already in the queue (unless this kernel is old
771 enough to use TASK_STOPPED for ptrace stops); but since
772 SIGSTOP is not an RT signal, it can only be queued once. */
773 kill_lwp (lwpid
, SIGSTOP
);
775 /* Finally, resume the stopped process. This will deliver the
776 SIGSTOP (or a higher priority signal, just like normal
777 PTRACE_ATTACH), which we'll catch later on. */
778 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_ARG3_TYPE
) 0, (PTRACE_ARG4_TYPE
) 0);
781 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
784 There are several cases to consider here:
786 1) gdbserver has already attached to the process and is being notified
787 of a new thread that is being created.
788 In this case we should ignore that SIGSTOP and resume the
789 process. This is handled below by setting stop_expected = 1,
790 and the fact that add_thread sets last_resume_kind ==
793 2) This is the first thread (the process thread), and we're attaching
794 to it via attach_inferior.
795 In this case we want the process thread to stop.
796 This is handled by having linux_attach set last_resume_kind ==
797 resume_stop after we return.
799 If the pid we are attaching to is also the tgid, we attach to and
800 stop all the existing threads. Otherwise, we attach to pid and
801 ignore any other threads in the same group as this pid.
803 3) GDB is connecting to gdbserver and is requesting an enumeration of all
805 In this case we want the thread to stop.
806 FIXME: This case is currently not properly handled.
807 We should wait for the SIGSTOP but don't. Things work apparently
808 because enough time passes between when we ptrace (ATTACH) and when
809 gdb makes the next ptrace call on the thread.
811 On the other hand, if we are currently trying to stop all threads, we
812 should treat the new thread as if we had sent it a SIGSTOP. This works
813 because we are guaranteed that the add_lwp call above added us to the
814 end of the list, and so the new thread has not yet reached
815 wait_for_sigstop (but will). */
816 new_lwp
->stop_expected
= 1;
820 linux_attach_lwp (unsigned long lwpid
)
822 linux_attach_lwp_1 (lwpid
, 0);
825 /* Attach to PID. If PID is the tgid, attach to it and all
829 linux_attach (unsigned long pid
)
831 /* Attach to PID. We will check for other threads
833 linux_attach_lwp_1 (pid
, 1);
834 linux_add_process (pid
, 1);
838 struct thread_info
*thread
;
840 /* Don't ignore the initial SIGSTOP if we just attached to this
841 process. It will be collected by wait shortly. */
842 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
843 thread
->last_resume_kind
= resume_stop
;
846 if (linux_proc_get_tgid (pid
) == pid
)
851 sprintf (pathname
, "/proc/%ld/task", pid
);
853 dir
= opendir (pathname
);
857 fprintf (stderr
, "Could not open /proc/%ld/task.\n", pid
);
862 /* At this point we attached to the tgid. Scan the task for
865 int new_threads_found
;
869 while (iterations
< 2)
871 new_threads_found
= 0;
872 /* Add all the other threads. While we go through the
873 threads, new threads may be spawned. Cycle through
874 the list of threads until we have done two iterations without
875 finding new threads. */
876 while ((dp
= readdir (dir
)) != NULL
)
879 lwp
= strtoul (dp
->d_name
, NULL
, 10);
881 /* Is this a new thread? */
883 && find_thread_ptid (ptid_build (pid
, lwp
, 0)) == NULL
)
885 linux_attach_lwp_1 (lwp
, 0);
890 Found and attached to new lwp %ld\n", lwp
);
894 if (!new_threads_found
)
915 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
917 struct counter
*counter
= args
;
919 if (ptid_get_pid (entry
->id
) == counter
->pid
)
921 if (++counter
->count
> 1)
929 last_thread_of_process_p (struct thread_info
*thread
)
931 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
932 int pid
= ptid_get_pid (ptid
);
933 struct counter counter
= { pid
, 0 };
935 return (find_inferior (&all_threads
,
936 second_thread_of_pid_p
, &counter
) == NULL
);
942 linux_kill_one_lwp (struct lwp_info
*lwp
)
944 int pid
= lwpid_of (lwp
);
946 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
947 there is no signal context, and ptrace(PTRACE_KILL) (or
948 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
949 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
950 alternative is to kill with SIGKILL. We only need one SIGKILL
951 per process, not one for each thread. But since we still support
952 linuxthreads, and we also support debugging programs using raw
953 clone without CLONE_THREAD, we send one for each thread. For
954 years, we used PTRACE_KILL only, so we're being a bit paranoid
955 about some old kernels where PTRACE_KILL might work better
956 (dubious if there are any such, but that's why it's paranoia), so
957 we try SIGKILL first, PTRACE_KILL second, and so we're fine
964 "LKL: kill (SIGKILL) %s, 0, 0 (%s)\n",
965 target_pid_to_str (ptid_of (lwp
)),
966 errno
? strerror (errno
) : "OK");
969 ptrace (PTRACE_KILL
, pid
, (PTRACE_ARG3_TYPE
) 0, (PTRACE_ARG4_TYPE
) 0);
972 "LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
973 target_pid_to_str (ptid_of (lwp
)),
974 errno
? strerror (errno
) : "OK");
977 /* Callback for `find_inferior'. Kills an lwp of a given process,
978 except the leader. */
981 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
983 struct thread_info
*thread
= (struct thread_info
*) entry
;
984 struct lwp_info
*lwp
= get_thread_lwp (thread
);
986 int pid
= * (int *) args
;
988 if (ptid_get_pid (entry
->id
) != pid
)
991 /* We avoid killing the first thread here, because of a Linux kernel (at
992 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
993 the children get a chance to be reaped, it will remain a zombie
996 if (lwpid_of (lwp
) == pid
)
999 fprintf (stderr
, "lkop: is last of process %s\n",
1000 target_pid_to_str (entry
->id
));
1006 linux_kill_one_lwp (lwp
);
1008 /* Make sure it died. The loop is most likely unnecessary. */
1009 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
1010 } while (pid
> 0 && WIFSTOPPED (wstat
));
1016 linux_kill (int pid
)
1018 struct process_info
*process
;
1019 struct lwp_info
*lwp
;
1023 process
= find_process_pid (pid
);
1024 if (process
== NULL
)
1027 /* If we're killing a running inferior, make sure it is stopped
1028 first, as PTRACE_KILL will not work otherwise. */
1029 stop_all_lwps (0, NULL
);
1031 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1033 /* See the comment in linux_kill_one_lwp. We did not kill the first
1034 thread in the list, so do so now. */
1035 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1040 fprintf (stderr
, "lk_1: cannot find lwp %ld, for pid: %d\n",
1041 lwpid_of (lwp
), pid
);
1046 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
1047 lwpid_of (lwp
), pid
);
1051 linux_kill_one_lwp (lwp
);
1053 /* Make sure it died. The loop is most likely unnecessary. */
1054 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
1055 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
1058 the_target
->mourn (process
);
1060 /* Since we presently can only stop all lwps of all processes, we
1061 need to unstop lwps of other processes. */
1062 unstop_all_lwps (0, NULL
);
1066 /* Get pending signal of THREAD, for detaching purposes. This is the
1067 signal the thread last stopped for, which we need to deliver to the
1068 thread when detaching, otherwise, it'd be suppressed/lost. */
1071 get_detach_signal (struct thread_info
*thread
)
1073 enum gdb_signal signo
= GDB_SIGNAL_0
;
1075 struct lwp_info
*lp
= get_thread_lwp (thread
);
1077 if (lp
->status_pending_p
)
1078 status
= lp
->status_pending
;
1081 /* If the thread had been suspended by gdbserver, and it stopped
1082 cleanly, then it'll have stopped with SIGSTOP. But we don't
1083 want to deliver that SIGSTOP. */
1084 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1085 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1088 /* Otherwise, we may need to deliver the signal we
1090 status
= lp
->last_status
;
1093 if (!WIFSTOPPED (status
))
1097 "GPS: lwp %s hasn't stopped: no pending signal\n",
1098 target_pid_to_str (ptid_of (lp
)));
1102 /* Extended wait statuses aren't real SIGTRAPs. */
1103 if (WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
1107 "GPS: lwp %s had stopped with extended "
1108 "status: no pending signal\n",
1109 target_pid_to_str (ptid_of (lp
)));
1113 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1115 if (program_signals_p
&& !program_signals
[signo
])
1119 "GPS: lwp %s had signal %s, but it is in nopass state\n",
1120 target_pid_to_str (ptid_of (lp
)),
1121 gdb_signal_to_string (signo
));
1124 else if (!program_signals_p
1125 /* If we have no way to know which signals GDB does not
1126 want to have passed to the program, assume
1127 SIGTRAP/SIGINT, which is GDB's default. */
1128 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1132 "GPS: lwp %s had signal %s, "
1133 "but we don't know if we should pass it. Default to not.\n",
1134 target_pid_to_str (ptid_of (lp
)),
1135 gdb_signal_to_string (signo
));
1142 "GPS: lwp %s has pending signal %s: delivering it.\n",
1143 target_pid_to_str (ptid_of (lp
)),
1144 gdb_signal_to_string (signo
));
1146 return WSTOPSIG (status
);
1151 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1153 struct thread_info
*thread
= (struct thread_info
*) entry
;
1154 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1155 int pid
= * (int *) args
;
1158 if (ptid_get_pid (entry
->id
) != pid
)
1161 /* If there is a pending SIGSTOP, get rid of it. */
1162 if (lwp
->stop_expected
)
1166 "Sending SIGCONT to %s\n",
1167 target_pid_to_str (ptid_of (lwp
)));
1169 kill_lwp (lwpid_of (lwp
), SIGCONT
);
1170 lwp
->stop_expected
= 0;
1173 /* Flush any pending changes to the process's registers. */
1174 regcache_invalidate_one ((struct inferior_list_entry
*)
1175 get_lwp_thread (lwp
));
1177 /* Pass on any pending signal for this thread. */
1178 sig
= get_detach_signal (thread
);
1180 /* Finally, let it resume. */
1181 if (the_low_target
.prepare_to_resume
!= NULL
)
1182 the_low_target
.prepare_to_resume (lwp
);
1183 if (ptrace (PTRACE_DETACH
, lwpid_of (lwp
), (PTRACE_ARG3_TYPE
) 0,
1184 (PTRACE_ARG4_TYPE
) (long) sig
) < 0)
1185 error (_("Can't detach %s: %s"),
1186 target_pid_to_str (ptid_of (lwp
)),
1194 linux_detach (int pid
)
1196 struct process_info
*process
;
1198 process
= find_process_pid (pid
);
1199 if (process
== NULL
)
1202 /* Stop all threads before detaching. First, ptrace requires that
1203 the thread is stopped to sucessfully detach. Second, thread_db
1204 may need to uninstall thread event breakpoints from memory, which
1205 only works with a stopped process anyway. */
1206 stop_all_lwps (0, NULL
);
1208 #ifdef USE_THREAD_DB
1209 thread_db_detach (process
);
1212 /* Stabilize threads (move out of jump pads). */
1213 stabilize_threads ();
1215 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1217 the_target
->mourn (process
);
1219 /* Since we presently can only stop all lwps of all processes, we
1220 need to unstop lwps of other processes. */
1221 unstop_all_lwps (0, NULL
);
1225 /* Remove all LWPs that belong to process PROC from the lwp list. */
1228 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1230 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1231 struct process_info
*process
= proc
;
1233 if (pid_of (lwp
) == pid_of (process
))
1240 linux_mourn (struct process_info
*process
)
1242 struct process_info_private
*priv
;
1244 #ifdef USE_THREAD_DB
1245 thread_db_mourn (process
);
1248 find_inferior (&all_lwps
, delete_lwp_callback
, process
);
1250 /* Freeing all private data. */
1251 priv
= process
->private;
1252 free (priv
->arch_private
);
1254 process
->private = NULL
;
1256 remove_process (process
);
1260 linux_join (int pid
)
1265 ret
= my_waitpid (pid
, &status
, 0);
1266 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1268 } while (ret
!= -1 || errno
!= ECHILD
);
1271 /* Return nonzero if the given thread is still alive. */
1273 linux_thread_alive (ptid_t ptid
)
1275 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1277 /* We assume we always know if a thread exits. If a whole process
1278 exited but we still haven't been able to report it to GDB, we'll
1279 hold on to the last lwp of the dead process. */
1286 /* Return 1 if this lwp has an interesting status pending. */
1288 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1290 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1291 ptid_t ptid
= * (ptid_t
*) arg
;
1292 struct thread_info
*thread
;
1294 /* Check if we're only interested in events from a specific process
1296 if (!ptid_equal (minus_one_ptid
, ptid
)
1297 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
1300 thread
= get_lwp_thread (lwp
);
1302 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1303 report any status pending the LWP may have. */
1304 if (thread
->last_resume_kind
== resume_stop
1305 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1308 return lwp
->status_pending_p
;
1312 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1314 ptid_t ptid
= *(ptid_t
*) data
;
1317 if (ptid_get_lwp (ptid
) != 0)
1318 lwp
= ptid_get_lwp (ptid
);
1320 lwp
= ptid_get_pid (ptid
);
1322 if (ptid_get_lwp (entry
->id
) == lwp
)
1329 find_lwp_pid (ptid_t ptid
)
1331 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
1334 static struct lwp_info
*
1335 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
1338 int to_wait_for
= -1;
1339 struct lwp_info
*child
= NULL
;
1342 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1344 if (ptid_equal (ptid
, minus_one_ptid
))
1345 to_wait_for
= -1; /* any child */
1347 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1353 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1354 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1357 perror_with_name ("waitpid");
1360 && (!WIFSTOPPED (*wstatp
)
1361 || (WSTOPSIG (*wstatp
) != 32
1362 && WSTOPSIG (*wstatp
) != 33)))
1363 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1365 child
= find_lwp_pid (pid_to_ptid (ret
));
1367 /* If we didn't find a process, one of two things presumably happened:
1368 - A process we started and then detached from has exited. Ignore it.
1369 - A process we are controlling has forked and the new child's stop
1370 was reported to us by the kernel. Save its PID. */
1371 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1373 add_to_pid_list (&stopped_pids
, ret
, *wstatp
);
1376 else if (child
== NULL
)
1381 child
->last_status
= *wstatp
;
1383 /* Architecture-specific setup after inferior is running.
1384 This needs to happen after we have attached to the inferior
1385 and it is stopped for the first time, but before we access
1386 any inferior registers. */
1389 the_low_target
.arch_setup ();
1390 #ifdef HAVE_LINUX_REGSETS
1391 memset (disabled_regsets
, 0, num_regsets
);
1396 /* Fetch the possibly triggered data watchpoint info and store it in
1399 On some archs, like x86, that use debug registers to set
1400 watchpoints, it's possible that the way to know which watched
1401 address trapped, is to check the register that is used to select
1402 which address to watch. Problem is, between setting the
1403 watchpoint and reading back which data address trapped, the user
1404 may change the set of watchpoints, and, as a consequence, GDB
1405 changes the debug registers in the inferior. To avoid reading
1406 back a stale stopped-data-address when that happens, we cache in
1407 LP the fact that a watchpoint trapped, and the corresponding data
1408 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1409 changes the debug registers meanwhile, we have the cached data we
1412 if (WIFSTOPPED (*wstatp
) && WSTOPSIG (*wstatp
) == SIGTRAP
)
1414 if (the_low_target
.stopped_by_watchpoint
== NULL
)
1416 child
->stopped_by_watchpoint
= 0;
1420 struct thread_info
*saved_inferior
;
1422 saved_inferior
= current_inferior
;
1423 current_inferior
= get_lwp_thread (child
);
1425 child
->stopped_by_watchpoint
1426 = the_low_target
.stopped_by_watchpoint ();
1428 if (child
->stopped_by_watchpoint
)
1430 if (the_low_target
.stopped_data_address
!= NULL
)
1431 child
->stopped_data_address
1432 = the_low_target
.stopped_data_address ();
1434 child
->stopped_data_address
= 0;
1437 current_inferior
= saved_inferior
;
1441 /* Store the STOP_PC, with adjustment applied. This depends on the
1442 architecture being defined already (so that CHILD has a valid
1443 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1445 if (WIFSTOPPED (*wstatp
))
1446 child
->stop_pc
= get_stop_pc (child
);
1449 && WIFSTOPPED (*wstatp
)
1450 && the_low_target
.get_pc
!= NULL
)
1452 struct thread_info
*saved_inferior
= current_inferior
;
1453 struct regcache
*regcache
;
1456 current_inferior
= get_lwp_thread (child
);
1457 regcache
= get_thread_regcache (current_inferior
, 1);
1458 pc
= (*the_low_target
.get_pc
) (regcache
);
1459 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1460 current_inferior
= saved_inferior
;
1466 /* This function should only be called if the LWP got a SIGTRAP.
1468 Handle any tracepoint steps or hits. Return true if a tracepoint
1469 event was handled, 0 otherwise. */
1472 handle_tracepoints (struct lwp_info
*lwp
)
1474 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1475 int tpoint_related_event
= 0;
1477 /* If this tracepoint hit causes a tracing stop, we'll immediately
1478 uninsert tracepoints. To do this, we temporarily pause all
1479 threads, unpatch away, and then unpause threads. We need to make
1480 sure the unpausing doesn't resume LWP too. */
1483 /* And we need to be sure that any all-threads-stopping doesn't try
1484 to move threads out of the jump pads, as it could deadlock the
1485 inferior (LWP could be in the jump pad, maybe even holding the
1488 /* Do any necessary step collect actions. */
1489 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1491 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1493 /* See if we just hit a tracepoint and do its main collect
1495 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1499 gdb_assert (lwp
->suspended
== 0);
1500 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1502 if (tpoint_related_event
)
1505 fprintf (stderr
, "got a tracepoint event\n");
1512 /* Convenience wrapper. Returns true if LWP is presently collecting a
1516 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1517 struct fast_tpoint_collect_status
*status
)
1519 CORE_ADDR thread_area
;
1521 if (the_low_target
.get_thread_area
== NULL
)
1524 /* Get the thread area address. This is used to recognize which
1525 thread is which when tracing with the in-process agent library.
1526 We don't read anything from the address, and treat it as opaque;
1527 it's the address itself that we assume is unique per-thread. */
1528 if ((*the_low_target
.get_thread_area
) (lwpid_of (lwp
), &thread_area
) == -1)
1531 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1534 /* The reason we resume in the caller, is because we want to be able
1535 to pass lwp->status_pending as WSTAT, and we need to clear
1536 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1537 refuses to resume. */
1540 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1542 struct thread_info
*saved_inferior
;
1544 saved_inferior
= current_inferior
;
1545 current_inferior
= get_lwp_thread (lwp
);
1548 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1549 && supports_fast_tracepoints ()
1550 && agent_loaded_p ())
1552 struct fast_tpoint_collect_status status
;
1557 Checking whether LWP %ld needs to move out of the jump pad.\n",
1560 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1563 || (WSTOPSIG (*wstat
) != SIGILL
1564 && WSTOPSIG (*wstat
) != SIGFPE
1565 && WSTOPSIG (*wstat
) != SIGSEGV
1566 && WSTOPSIG (*wstat
) != SIGBUS
))
1568 lwp
->collecting_fast_tracepoint
= r
;
1572 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1574 /* Haven't executed the original instruction yet.
1575 Set breakpoint there, and wait till it's hit,
1576 then single-step until exiting the jump pad. */
1577 lwp
->exit_jump_pad_bkpt
1578 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1583 Checking whether LWP %ld needs to move out of the jump pad...it does\n",
1585 current_inferior
= saved_inferior
;
1592 /* If we get a synchronous signal while collecting, *and*
1593 while executing the (relocated) original instruction,
1594 reset the PC to point at the tpoint address, before
1595 reporting to GDB. Otherwise, it's an IPA lib bug: just
1596 report the signal to GDB, and pray for the best. */
1598 lwp
->collecting_fast_tracepoint
= 0;
1601 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1602 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1605 struct regcache
*regcache
;
1607 /* The si_addr on a few signals references the address
1608 of the faulting instruction. Adjust that as
1610 if ((WSTOPSIG (*wstat
) == SIGILL
1611 || WSTOPSIG (*wstat
) == SIGFPE
1612 || WSTOPSIG (*wstat
) == SIGBUS
1613 || WSTOPSIG (*wstat
) == SIGSEGV
)
1614 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
),
1615 (PTRACE_ARG3_TYPE
) 0, &info
) == 0
1616 /* Final check just to make sure we don't clobber
1617 the siginfo of non-kernel-sent signals. */
1618 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1620 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1621 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
),
1622 (PTRACE_ARG3_TYPE
) 0, &info
);
1625 regcache
= get_thread_regcache (get_lwp_thread (lwp
), 1);
1626 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1627 lwp
->stop_pc
= status
.tpoint_addr
;
1629 /* Cancel any fast tracepoint lock this thread was
1631 force_unlock_trace_buffer ();
1634 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1638 "Cancelling fast exit-jump-pad: removing bkpt. "
1639 "stopping all threads momentarily.\n");
1641 stop_all_lwps (1, lwp
);
1642 cancel_breakpoints ();
1644 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1645 lwp
->exit_jump_pad_bkpt
= NULL
;
1647 unstop_all_lwps (1, lwp
);
1649 gdb_assert (lwp
->suspended
>= 0);
1656 Checking whether LWP %ld needs to move out of the jump pad...no\n",
1659 current_inferior
= saved_inferior
;
1663 /* Enqueue one signal in the "signals to report later when out of the
1667 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1669 struct pending_signals
*p_sig
;
1673 Deferring signal %d for LWP %ld.\n", WSTOPSIG (*wstat
), lwpid_of (lwp
));
1677 struct pending_signals
*sig
;
1679 for (sig
= lwp
->pending_signals_to_report
;
1683 " Already queued %d\n",
1686 fprintf (stderr
, " (no more currently queued signals)\n");
1689 /* Don't enqueue non-RT signals if they are already in the deferred
1690 queue. (SIGSTOP being the easiest signal to see ending up here
1692 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1694 struct pending_signals
*sig
;
1696 for (sig
= lwp
->pending_signals_to_report
;
1700 if (sig
->signal
== WSTOPSIG (*wstat
))
1704 "Not requeuing already queued non-RT signal %d"
1713 p_sig
= xmalloc (sizeof (*p_sig
));
1714 p_sig
->prev
= lwp
->pending_signals_to_report
;
1715 p_sig
->signal
= WSTOPSIG (*wstat
);
1716 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1717 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), (PTRACE_ARG3_TYPE
) 0,
1720 lwp
->pending_signals_to_report
= p_sig
;
1723 /* Dequeue one signal from the "signals to report later when out of
1724 the jump pad" list. */
1727 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1729 if (lwp
->pending_signals_to_report
!= NULL
)
1731 struct pending_signals
**p_sig
;
1733 p_sig
= &lwp
->pending_signals_to_report
;
1734 while ((*p_sig
)->prev
!= NULL
)
1735 p_sig
= &(*p_sig
)->prev
;
1737 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1738 if ((*p_sig
)->info
.si_signo
!= 0)
1739 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), (PTRACE_ARG3_TYPE
) 0,
1745 fprintf (stderr
, "Reporting deferred signal %d for LWP %ld.\n",
1746 WSTOPSIG (*wstat
), lwpid_of (lwp
));
1750 struct pending_signals
*sig
;
1752 for (sig
= lwp
->pending_signals_to_report
;
1756 " Still queued %d\n",
1759 fprintf (stderr
, " (no more queued signals)\n");
1768 /* Arrange for a breakpoint to be hit again later. We don't keep the
1769 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1770 will handle the current event, eventually we will resume this LWP,
1771 and this breakpoint will trap again. */
1774 cancel_breakpoint (struct lwp_info
*lwp
)
1776 struct thread_info
*saved_inferior
;
1778 /* There's nothing to do if we don't support breakpoints. */
1779 if (!supports_breakpoints ())
1782 /* breakpoint_at reads from current inferior. */
1783 saved_inferior
= current_inferior
;
1784 current_inferior
= get_lwp_thread (lwp
);
1786 if ((*the_low_target
.breakpoint_at
) (lwp
->stop_pc
))
1790 "CB: Push back breakpoint for %s\n",
1791 target_pid_to_str (ptid_of (lwp
)));
1793 /* Back up the PC if necessary. */
1794 if (the_low_target
.decr_pc_after_break
)
1796 struct regcache
*regcache
1797 = get_thread_regcache (current_inferior
, 1);
1798 (*the_low_target
.set_pc
) (regcache
, lwp
->stop_pc
);
1801 current_inferior
= saved_inferior
;
1808 "CB: No breakpoint found at %s for [%s]\n",
1809 paddress (lwp
->stop_pc
),
1810 target_pid_to_str (ptid_of (lwp
)));
1813 current_inferior
= saved_inferior
;
1817 /* When the event-loop is doing a step-over, this points at the thread
1819 ptid_t step_over_bkpt
;
1821 /* Wait for an event from child PID. If PID is -1, wait for any
1822 child. Store the stop status through the status pointer WSTAT.
1823 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1824 event was found and OPTIONS contains WNOHANG. Return the PID of
1825 the stopped child otherwise. */
1828 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1830 struct lwp_info
*event_child
, *requested_child
;
1834 requested_child
= NULL
;
1836 /* Check for a lwp with a pending status. */
1838 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
1840 event_child
= (struct lwp_info
*)
1841 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1842 if (debug_threads
&& event_child
)
1843 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1847 requested_child
= find_lwp_pid (ptid
);
1849 if (stopping_threads
== NOT_STOPPING_THREADS
1850 && requested_child
->status_pending_p
1851 && requested_child
->collecting_fast_tracepoint
)
1853 enqueue_one_deferred_signal (requested_child
,
1854 &requested_child
->status_pending
);
1855 requested_child
->status_pending_p
= 0;
1856 requested_child
->status_pending
= 0;
1857 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
1860 if (requested_child
->suspended
1861 && requested_child
->status_pending_p
)
1862 fatal ("requesting an event out of a suspended child?");
1864 if (requested_child
->status_pending_p
)
1865 event_child
= requested_child
;
1868 if (event_child
!= NULL
)
1871 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1872 lwpid_of (event_child
), event_child
->status_pending
);
1873 *wstat
= event_child
->status_pending
;
1874 event_child
->status_pending_p
= 0;
1875 event_child
->status_pending
= 0;
1876 current_inferior
= get_lwp_thread (event_child
);
1877 return lwpid_of (event_child
);
1880 if (ptid_is_pid (ptid
))
1882 /* A request to wait for a specific tgid. This is not possible
1883 with waitpid, so instead, we wait for any child, and leave
1884 children we're not interested in right now with a pending
1885 status to report later. */
1886 wait_ptid
= minus_one_ptid
;
1891 /* We only enter this loop if no process has a pending wait status. Thus
1892 any action taken in response to a wait status inside this loop is
1893 responding as soon as we detect the status, not after any pending
1897 event_child
= linux_wait_for_lwp (wait_ptid
, wstat
, options
);
1899 if ((options
& WNOHANG
) && event_child
== NULL
)
1902 fprintf (stderr
, "WNOHANG set, no event found\n");
1906 if (event_child
== NULL
)
1907 error ("event from unknown child");
1909 if (ptid_is_pid (ptid
)
1910 && ptid_get_pid (ptid
) != ptid_get_pid (ptid_of (event_child
)))
1912 if (! WIFSTOPPED (*wstat
))
1913 mark_lwp_dead (event_child
, *wstat
);
1916 event_child
->status_pending_p
= 1;
1917 event_child
->status_pending
= *wstat
;
1922 current_inferior
= get_lwp_thread (event_child
);
1924 /* Check for thread exit. */
1925 if (! WIFSTOPPED (*wstat
))
1928 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1930 /* If the last thread is exiting, just return. */
1931 if (last_thread_of_process_p (current_inferior
))
1934 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1935 lwpid_of (event_child
));
1936 return lwpid_of (event_child
);
1941 current_inferior
= (struct thread_info
*) all_threads
.head
;
1943 fprintf (stderr
, "Current inferior is now %ld\n",
1944 lwpid_of (get_thread_lwp (current_inferior
)));
1948 current_inferior
= NULL
;
1950 fprintf (stderr
, "Current inferior is now <NULL>\n");
1953 /* If we were waiting for this particular child to do something...
1954 well, it did something. */
1955 if (requested_child
!= NULL
)
1957 int lwpid
= lwpid_of (event_child
);
1959 /* Cancel the step-over operation --- the thread that
1960 started it is gone. */
1961 if (finish_step_over (event_child
))
1962 unstop_all_lwps (1, event_child
);
1963 delete_lwp (event_child
);
1967 delete_lwp (event_child
);
1969 /* Wait for a more interesting event. */
1973 if (event_child
->must_set_ptrace_flags
)
1975 linux_enable_event_reporting (lwpid_of (event_child
));
1976 event_child
->must_set_ptrace_flags
= 0;
1979 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1980 && *wstat
>> 16 != 0)
1982 handle_extended_wait (event_child
, *wstat
);
1986 if (WIFSTOPPED (*wstat
)
1987 && WSTOPSIG (*wstat
) == SIGSTOP
1988 && event_child
->stop_expected
)
1993 fprintf (stderr
, "Expected stop.\n");
1994 event_child
->stop_expected
= 0;
1996 should_stop
= (current_inferior
->last_resume_kind
== resume_stop
1997 || stopping_threads
!= NOT_STOPPING_THREADS
);
2001 linux_resume_one_lwp (event_child
,
2002 event_child
->stepping
, 0, NULL
);
2007 return lwpid_of (event_child
);
2014 /* Count the LWP's that have had events. */
2017 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2019 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2020 struct thread_info
*thread
= get_lwp_thread (lp
);
2023 gdb_assert (count
!= NULL
);
2025 /* Count only resumed LWPs that have a SIGTRAP event pending that
2026 should be reported to GDB. */
2027 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2028 && thread
->last_resume_kind
!= resume_stop
2029 && lp
->status_pending_p
2030 && WIFSTOPPED (lp
->status_pending
)
2031 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2032 && !breakpoint_inserted_here (lp
->stop_pc
))
2038 /* Select the LWP (if any) that is currently being single-stepped. */
2041 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2043 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2044 struct thread_info
*thread
= get_lwp_thread (lp
);
2046 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2047 && thread
->last_resume_kind
== resume_step
2048 && lp
->status_pending_p
)
2054 /* Select the Nth LWP that has had a SIGTRAP event that should be
2058 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2060 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2061 struct thread_info
*thread
= get_lwp_thread (lp
);
2062 int *selector
= data
;
2064 gdb_assert (selector
!= NULL
);
2066 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2067 if (thread
->last_resume_kind
!= resume_stop
2068 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2069 && lp
->status_pending_p
2070 && WIFSTOPPED (lp
->status_pending
)
2071 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2072 && !breakpoint_inserted_here (lp
->stop_pc
))
2073 if ((*selector
)-- == 0)
2080 cancel_breakpoints_callback (struct inferior_list_entry
*entry
, void *data
)
2082 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2083 struct thread_info
*thread
= get_lwp_thread (lp
);
2084 struct lwp_info
*event_lp
= data
;
2086 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
2090 /* If a LWP other than the LWP that we're reporting an event for has
2091 hit a GDB breakpoint (as opposed to some random trap signal),
2092 then just arrange for it to hit it again later. We don't keep
2093 the SIGTRAP status and don't forward the SIGTRAP signal to the
2094 LWP. We will handle the current event, eventually we will resume
2095 all LWPs, and this one will get its breakpoint trap again.
2097 If we do not do this, then we run the risk that the user will
2098 delete or disable the breakpoint, but the LWP will have already
2101 if (thread
->last_resume_kind
!= resume_stop
2102 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2103 && lp
->status_pending_p
2104 && WIFSTOPPED (lp
->status_pending
)
2105 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2107 && !lp
->stopped_by_watchpoint
2108 && cancel_breakpoint (lp
))
2109 /* Throw away the SIGTRAP. */
2110 lp
->status_pending_p
= 0;
2116 linux_cancel_breakpoints (void)
2118 find_inferior (&all_lwps
, cancel_breakpoints_callback
, NULL
);
2121 /* Select one LWP out of those that have events pending. */
2124 select_event_lwp (struct lwp_info
**orig_lp
)
2127 int random_selector
;
2128 struct lwp_info
*event_lp
;
2130 /* Give preference to any LWP that is being single-stepped. */
2132 = (struct lwp_info
*) find_inferior (&all_lwps
,
2133 select_singlestep_lwp_callback
, NULL
);
2134 if (event_lp
!= NULL
)
2138 "SEL: Select single-step %s\n",
2139 target_pid_to_str (ptid_of (event_lp
)));
2143 /* No single-stepping LWP. Select one at random, out of those
2144 which have had SIGTRAP events. */
2146 /* First see how many SIGTRAP events we have. */
2147 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
2149 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
2150 random_selector
= (int)
2151 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2153 if (debug_threads
&& num_events
> 1)
2155 "SEL: Found %d SIGTRAP events, selecting #%d\n",
2156 num_events
, random_selector
);
2158 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
2159 select_event_lwp_callback
,
2163 if (event_lp
!= NULL
)
2165 /* Switch the event LWP. */
2166 *orig_lp
= event_lp
;
2170 /* Decrement the suspend count of an LWP. */
2173 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2175 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2177 /* Ignore EXCEPT. */
2183 gdb_assert (lwp
->suspended
>= 0);
2187 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2191 unsuspend_all_lwps (struct lwp_info
*except
)
2193 find_inferior (&all_lwps
, unsuspend_one_lwp
, except
);
2196 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2197 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2199 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2200 static ptid_t
linux_wait_1 (ptid_t ptid
,
2201 struct target_waitstatus
*ourstatus
,
2202 int target_options
);
2204 /* Stabilize threads (move out of jump pads).
2206 If a thread is midway collecting a fast tracepoint, we need to
2207 finish the collection and move it out of the jump pad before
2208 reporting the signal.
2210 This avoids recursion while collecting (when a signal arrives
2211 midway, and the signal handler itself collects), which would trash
2212 the trace buffer. In case the user set a breakpoint in a signal
2213 handler, this avoids the backtrace showing the jump pad, etc..
2214 Most importantly, there are certain things we can't do safely if
2215 threads are stopped in a jump pad (or in its callee's). For
2218 - starting a new trace run. A thread still collecting the
2219 previous run, could trash the trace buffer when resumed. The trace
2220 buffer control structures would have been reset but the thread had
2221 no way to tell. The thread could even midway memcpy'ing to the
2222 buffer, which would mean that when resumed, it would clobber the
2223 trace buffer that had been set for a new run.
2225 - we can't rewrite/reuse the jump pads for new tracepoints
2226 safely. Say you do tstart while a thread is stopped midway while
2227 collecting. When the thread is later resumed, it finishes the
2228 collection, and returns to the jump pad, to execute the original
2229 instruction that was under the tracepoint jump at the time the
2230 older run had been started. If the jump pad had been rewritten
2231 since for something else in the new run, the thread would now
2232 execute the wrong / random instructions. */
2235 linux_stabilize_threads (void)
2237 struct thread_info
*save_inferior
;
2238 struct lwp_info
*lwp_stuck
;
2241 = (struct lwp_info
*) find_inferior (&all_lwps
,
2242 stuck_in_jump_pad_callback
, NULL
);
2243 if (lwp_stuck
!= NULL
)
2246 fprintf (stderr
, "can't stabilize, LWP %ld is stuck in jump pad\n",
2247 lwpid_of (lwp_stuck
));
2251 save_inferior
= current_inferior
;
2253 stabilizing_threads
= 1;
2256 for_each_inferior (&all_lwps
, move_out_of_jump_pad_callback
);
2258 /* Loop until all are stopped out of the jump pads. */
2259 while (find_inferior (&all_lwps
, lwp_running
, NULL
) != NULL
)
2261 struct target_waitstatus ourstatus
;
2262 struct lwp_info
*lwp
;
2265 /* Note that we go through the full wait even loop. While
2266 moving threads out of jump pad, we need to be able to step
2267 over internal breakpoints and such. */
2268 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2270 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2272 lwp
= get_thread_lwp (current_inferior
);
2277 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2278 || current_inferior
->last_resume_kind
== resume_stop
)
2280 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2281 enqueue_one_deferred_signal (lwp
, &wstat
);
2286 find_inferior (&all_lwps
, unsuspend_one_lwp
, NULL
);
2288 stabilizing_threads
= 0;
2290 current_inferior
= save_inferior
;
2295 = (struct lwp_info
*) find_inferior (&all_lwps
,
2296 stuck_in_jump_pad_callback
, NULL
);
2297 if (lwp_stuck
!= NULL
)
2298 fprintf (stderr
, "couldn't stabilize, LWP %ld got stuck in jump pad\n",
2299 lwpid_of (lwp_stuck
));
2303 /* Wait for process, returns status. */
2306 linux_wait_1 (ptid_t ptid
,
2307 struct target_waitstatus
*ourstatus
, int target_options
)
2310 struct lwp_info
*event_child
;
2313 int step_over_finished
;
2314 int bp_explains_trap
;
2315 int maybe_internal_trap
;
2319 /* Translate generic target options into linux options. */
2321 if (target_options
& TARGET_WNOHANG
)
2325 bp_explains_trap
= 0;
2327 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2329 /* If we were only supposed to resume one thread, only wait for
2330 that thread - if it's still alive. If it died, however - which
2331 can happen if we're coming from the thread death case below -
2332 then we need to make sure we restart the other threads. We could
2333 pick a thread at random or restart all; restarting all is less
2336 && !ptid_equal (cont_thread
, null_ptid
)
2337 && !ptid_equal (cont_thread
, minus_one_ptid
))
2339 struct thread_info
*thread
;
2341 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
2344 /* No stepping, no signal - unless one is pending already, of course. */
2347 struct thread_resume resume_info
;
2348 resume_info
.thread
= minus_one_ptid
;
2349 resume_info
.kind
= resume_continue
;
2350 resume_info
.sig
= 0;
2351 linux_resume (&resume_info
, 1);
2357 if (ptid_equal (step_over_bkpt
, null_ptid
))
2358 pid
= linux_wait_for_event (ptid
, &w
, options
);
2362 fprintf (stderr
, "step_over_bkpt set [%s], doing a blocking wait\n",
2363 target_pid_to_str (step_over_bkpt
));
2364 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2367 if (pid
== 0) /* only if TARGET_WNOHANG */
2370 event_child
= get_thread_lwp (current_inferior
);
2372 /* If we are waiting for a particular child, and it exited,
2373 linux_wait_for_event will return its exit status. Similarly if
2374 the last child exited. If this is not the last child, however,
2375 do not report it as exited until there is a 'thread exited' response
2376 available in the remote protocol. Instead, just wait for another event.
2377 This should be safe, because if the thread crashed we will already
2378 have reported the termination signal to GDB; that should stop any
2379 in-progress stepping operations, etc.
2381 Report the exit status of the last thread to exit. This matches
2382 LinuxThreads' behavior. */
2384 if (last_thread_of_process_p (current_inferior
))
2386 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2390 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2391 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2395 "\nChild exited with retcode = %x \n",
2400 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2401 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
2405 "\nChild terminated with signal = %x \n",
2410 return ptid_of (event_child
);
2415 if (!WIFSTOPPED (w
))
2419 /* If this event was not handled before, and is not a SIGTRAP, we
2420 report it. SIGILL and SIGSEGV are also treated as traps in case
2421 a breakpoint is inserted at the current PC. If this target does
2422 not support internal breakpoints at all, we also report the
2423 SIGTRAP without further processing; it's of no concern to us. */
2425 = (supports_breakpoints ()
2426 && (WSTOPSIG (w
) == SIGTRAP
2427 || ((WSTOPSIG (w
) == SIGILL
2428 || WSTOPSIG (w
) == SIGSEGV
)
2429 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2431 if (maybe_internal_trap
)
2433 /* Handle anything that requires bookkeeping before deciding to
2434 report the event or continue waiting. */
2436 /* First check if we can explain the SIGTRAP with an internal
2437 breakpoint, or if we should possibly report the event to GDB.
2438 Do this before anything that may remove or insert a
2440 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2442 /* We have a SIGTRAP, possibly a step-over dance has just
2443 finished. If so, tweak the state machine accordingly,
2444 reinsert breakpoints and delete any reinsert (software
2445 single-step) breakpoints. */
2446 step_over_finished
= finish_step_over (event_child
);
2448 /* Now invoke the callbacks of any internal breakpoints there. */
2449 check_breakpoints (event_child
->stop_pc
);
2451 /* Handle tracepoint data collecting. This may overflow the
2452 trace buffer, and cause a tracing stop, removing
2454 trace_event
= handle_tracepoints (event_child
);
2456 if (bp_explains_trap
)
2458 /* If we stepped or ran into an internal breakpoint, we've
2459 already handled it. So next time we resume (from this
2460 PC), we should step over it. */
2462 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2464 if (breakpoint_here (event_child
->stop_pc
))
2465 event_child
->need_step_over
= 1;
2470 /* We have some other signal, possibly a step-over dance was in
2471 progress, and it should be cancelled too. */
2472 step_over_finished
= finish_step_over (event_child
);
2475 /* We have all the data we need. Either report the event to GDB, or
2476 resume threads and keep waiting for more. */
2478 /* If we're collecting a fast tracepoint, finish the collection and
2479 move out of the jump pad before delivering a signal. See
2480 linux_stabilize_threads. */
2483 && WSTOPSIG (w
) != SIGTRAP
2484 && supports_fast_tracepoints ()
2485 && agent_loaded_p ())
2489 "Got signal %d for LWP %ld. Check if we need "
2490 "to defer or adjust it.\n",
2491 WSTOPSIG (w
), lwpid_of (event_child
));
2493 /* Allow debugging the jump pad itself. */
2494 if (current_inferior
->last_resume_kind
!= resume_step
2495 && maybe_move_out_of_jump_pad (event_child
, &w
))
2497 enqueue_one_deferred_signal (event_child
, &w
);
2501 "Signal %d for LWP %ld deferred (in jump pad)\n",
2502 WSTOPSIG (w
), lwpid_of (event_child
));
2504 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2509 if (event_child
->collecting_fast_tracepoint
)
2513 LWP %ld was trying to move out of the jump pad (%d). \
2514 Check if we're already there.\n",
2515 lwpid_of (event_child
),
2516 event_child
->collecting_fast_tracepoint
);
2520 event_child
->collecting_fast_tracepoint
2521 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2523 if (event_child
->collecting_fast_tracepoint
!= 1)
2525 /* No longer need this breakpoint. */
2526 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2530 "No longer need exit-jump-pad bkpt; removing it."
2531 "stopping all threads momentarily.\n");
2533 /* Other running threads could hit this breakpoint.
2534 We don't handle moribund locations like GDB does,
2535 instead we always pause all threads when removing
2536 breakpoints, so that any step-over or
2537 decr_pc_after_break adjustment is always taken
2538 care of while the breakpoint is still
2540 stop_all_lwps (1, event_child
);
2541 cancel_breakpoints ();
2543 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2544 event_child
->exit_jump_pad_bkpt
= NULL
;
2546 unstop_all_lwps (1, event_child
);
2548 gdb_assert (event_child
->suspended
>= 0);
2552 if (event_child
->collecting_fast_tracepoint
== 0)
2556 "fast tracepoint finished "
2557 "collecting successfully.\n");
2559 /* We may have a deferred signal to report. */
2560 if (dequeue_one_deferred_signal (event_child
, &w
))
2563 fprintf (stderr
, "dequeued one signal.\n");
2568 fprintf (stderr
, "no deferred signals.\n");
2570 if (stabilizing_threads
)
2572 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2573 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
2574 return ptid_of (event_child
);
2580 /* Check whether GDB would be interested in this event. */
2582 /* If GDB is not interested in this signal, don't stop other
2583 threads, and don't report it to GDB. Just resume the inferior
2584 right away. We do this for threading-related signals as well as
2585 any that GDB specifically requested we ignore. But never ignore
2586 SIGSTOP if we sent it ourselves, and do not ignore signals when
2587 stepping - they may require special handling to skip the signal
2589 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2592 && current_inferior
->last_resume_kind
!= resume_step
2594 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2595 (current_process ()->private->thread_db
!= NULL
2596 && (WSTOPSIG (w
) == __SIGRTMIN
2597 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2600 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
2601 && !(WSTOPSIG (w
) == SIGSTOP
2602 && current_inferior
->last_resume_kind
== resume_stop
))))
2604 siginfo_t info
, *info_p
;
2607 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
2608 WSTOPSIG (w
), lwpid_of (event_child
));
2610 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
),
2611 (PTRACE_ARG3_TYPE
) 0, &info
) == 0)
2615 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2616 WSTOPSIG (w
), info_p
);
2620 /* If GDB wanted this thread to single step, we always want to
2621 report the SIGTRAP, and let GDB handle it. Watchpoints should
2622 always be reported. So should signals we can't explain. A
2623 SIGTRAP we can't explain could be a GDB breakpoint --- we may or
2624 not support Z0 breakpoints. If we do, we're be able to handle
2625 GDB breakpoints on top of internal breakpoints, by handling the
2626 internal breakpoint and still reporting the event to GDB. If we
2627 don't, we're out of luck, GDB won't see the breakpoint hit. */
2628 report_to_gdb
= (!maybe_internal_trap
2629 || current_inferior
->last_resume_kind
== resume_step
2630 || event_child
->stopped_by_watchpoint
2631 || (!step_over_finished
2632 && !bp_explains_trap
&& !trace_event
)
2633 || (gdb_breakpoint_here (event_child
->stop_pc
)
2634 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
2635 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
)));
2637 run_breakpoint_commands (event_child
->stop_pc
);
2639 /* We found no reason GDB would want us to stop. We either hit one
2640 of our own breakpoints, or finished an internal step GDB
2641 shouldn't know about. */
2646 if (bp_explains_trap
)
2647 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2648 if (step_over_finished
)
2649 fprintf (stderr
, "Step-over finished.\n");
2651 fprintf (stderr
, "Tracepoint event.\n");
2654 /* We're not reporting this breakpoint to GDB, so apply the
2655 decr_pc_after_break adjustment to the inferior's regcache
2658 if (the_low_target
.set_pc
!= NULL
)
2660 struct regcache
*regcache
2661 = get_thread_regcache (get_lwp_thread (event_child
), 1);
2662 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2665 /* We may have finished stepping over a breakpoint. If so,
2666 we've stopped and suspended all LWPs momentarily except the
2667 stepping one. This is where we resume them all again. We're
2668 going to keep waiting, so use proceed, which handles stepping
2669 over the next breakpoint. */
2671 fprintf (stderr
, "proceeding all threads.\n");
2673 if (step_over_finished
)
2674 unsuspend_all_lwps (event_child
);
2676 proceed_all_lwps ();
2682 if (current_inferior
->last_resume_kind
== resume_step
)
2683 fprintf (stderr
, "GDB wanted to single-step, reporting event.\n");
2684 if (event_child
->stopped_by_watchpoint
)
2685 fprintf (stderr
, "Stopped by watchpoint.\n");
2686 if (gdb_breakpoint_here (event_child
->stop_pc
))
2687 fprintf (stderr
, "Stopped by GDB breakpoint.\n");
2689 fprintf (stderr
, "Hit a non-gdbserver trap event.\n");
2692 /* Alright, we're going to report a stop. */
2694 if (!non_stop
&& !stabilizing_threads
)
2696 /* In all-stop, stop all threads. */
2697 stop_all_lwps (0, NULL
);
2699 /* If we're not waiting for a specific LWP, choose an event LWP
2700 from among those that have had events. Giving equal priority
2701 to all LWPs that have had events helps prevent
2703 if (ptid_equal (ptid
, minus_one_ptid
))
2705 event_child
->status_pending_p
= 1;
2706 event_child
->status_pending
= w
;
2708 select_event_lwp (&event_child
);
2710 event_child
->status_pending_p
= 0;
2711 w
= event_child
->status_pending
;
2714 /* Now that we've selected our final event LWP, cancel any
2715 breakpoints in other LWPs that have hit a GDB breakpoint.
2716 See the comment in cancel_breakpoints_callback to find out
2718 find_inferior (&all_lwps
, cancel_breakpoints_callback
, event_child
);
2720 /* If we were going a step-over, all other threads but the stepping one
2721 had been paused in start_step_over, with their suspend counts
2722 incremented. We don't want to do a full unstop/unpause, because we're
2723 in all-stop mode (so we want threads stopped), but we still need to
2724 unsuspend the other threads, to decrement their `suspended' count
2726 if (step_over_finished
)
2727 unsuspend_all_lwps (event_child
);
2729 /* Stabilize threads (move out of jump pads). */
2730 stabilize_threads ();
2734 /* If we just finished a step-over, then all threads had been
2735 momentarily paused. In all-stop, that's fine, we want
2736 threads stopped by now anyway. In non-stop, we need to
2737 re-resume threads that GDB wanted to be running. */
2738 if (step_over_finished
)
2739 unstop_all_lwps (1, event_child
);
2742 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2744 if (current_inferior
->last_resume_kind
== resume_stop
2745 && WSTOPSIG (w
) == SIGSTOP
)
2747 /* A thread that has been requested to stop by GDB with vCont;t,
2748 and it stopped cleanly, so report as SIG0. The use of
2749 SIGSTOP is an implementation detail. */
2750 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
2752 else if (current_inferior
->last_resume_kind
== resume_stop
2753 && WSTOPSIG (w
) != SIGSTOP
)
2755 /* A thread that has been requested to stop by GDB with vCont;t,
2756 but, it stopped for other reasons. */
2757 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
2761 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
2764 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
2767 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
2768 target_pid_to_str (ptid_of (event_child
)),
2770 ourstatus
->value
.sig
);
2772 return ptid_of (event_child
);
2775 /* Get rid of any pending event in the pipe. */
2777 async_file_flush (void)
2783 ret
= read (linux_event_pipe
[0], &buf
, 1);
2784 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
2787 /* Put something in the pipe, so the event loop wakes up. */
2789 async_file_mark (void)
2793 async_file_flush ();
2796 ret
= write (linux_event_pipe
[1], "+", 1);
2797 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
2799 /* Ignore EAGAIN. If the pipe is full, the event loop will already
2800 be awakened anyway. */
2804 linux_wait (ptid_t ptid
,
2805 struct target_waitstatus
*ourstatus
, int target_options
)
2810 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
2812 /* Flush the async file first. */
2813 if (target_is_async_p ())
2814 async_file_flush ();
2816 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
2818 /* If at least one stop was reported, there may be more. A single
2819 SIGCHLD can signal more than one child stop. */
2820 if (target_is_async_p ()
2821 && (target_options
& TARGET_WNOHANG
) != 0
2822 && !ptid_equal (event_ptid
, null_ptid
))
2828 /* Send a signal to an LWP. */
2831 kill_lwp (unsigned long lwpid
, int signo
)
2833 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2834 fails, then we are not using nptl threads and we should be using kill. */
2838 static int tkill_failed
;
2845 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2846 if (errno
!= ENOSYS
)
2853 return kill (lwpid
, signo
);
2857 linux_stop_lwp (struct lwp_info
*lwp
)
2863 send_sigstop (struct lwp_info
*lwp
)
2867 pid
= lwpid_of (lwp
);
2869 /* If we already have a pending stop signal for this process, don't
2871 if (lwp
->stop_expected
)
2874 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
2880 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
2882 lwp
->stop_expected
= 1;
2883 kill_lwp (pid
, SIGSTOP
);
2887 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
2889 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2891 /* Ignore EXCEPT. */
2902 /* Increment the suspend count of an LWP, and stop it, if not stopped
2905 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
2908 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2910 /* Ignore EXCEPT. */
2916 return send_sigstop_callback (entry
, except
);
2920 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
2922 /* It's dead, really. */
2925 /* Store the exit status for later. */
2926 lwp
->status_pending_p
= 1;
2927 lwp
->status_pending
= wstat
;
2929 /* Prevent trying to stop it. */
2932 /* No further stops are expected from a dead lwp. */
2933 lwp
->stop_expected
= 0;
2937 wait_for_sigstop (struct inferior_list_entry
*entry
)
2939 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2940 struct thread_info
*saved_inferior
;
2949 fprintf (stderr
, "wait_for_sigstop: LWP %ld already stopped\n",
2954 saved_inferior
= current_inferior
;
2955 if (saved_inferior
!= NULL
)
2956 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
2958 saved_tid
= null_ptid
; /* avoid bogus unused warning */
2960 ptid
= lwp
->head
.id
;
2963 fprintf (stderr
, "wait_for_sigstop: pulling one event\n");
2965 pid
= linux_wait_for_event (ptid
, &wstat
, __WALL
);
2967 /* If we stopped with a non-SIGSTOP signal, save it for later
2968 and record the pending SIGSTOP. If the process exited, just
2970 if (WIFSTOPPED (wstat
))
2973 fprintf (stderr
, "LWP %ld stopped with signal %d\n",
2974 lwpid_of (lwp
), WSTOPSIG (wstat
));
2976 if (WSTOPSIG (wstat
) != SIGSTOP
)
2979 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
2980 lwpid_of (lwp
), wstat
);
2982 lwp
->status_pending_p
= 1;
2983 lwp
->status_pending
= wstat
;
2989 fprintf (stderr
, "Process %d exited while stopping LWPs\n", pid
);
2991 lwp
= find_lwp_pid (pid_to_ptid (pid
));
2994 /* Leave this status pending for the next time we're able to
2995 report it. In the mean time, we'll report this lwp as
2996 dead to GDB, so GDB doesn't try to read registers and
2997 memory from it. This can only happen if this was the
2998 last thread of the process; otherwise, PID is removed
2999 from the thread tables before linux_wait_for_event
3001 mark_lwp_dead (lwp
, wstat
);
3005 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
3006 current_inferior
= saved_inferior
;
3010 fprintf (stderr
, "Previously current thread died.\n");
3014 /* We can't change the current inferior behind GDB's back,
3015 otherwise, a subsequent command may apply to the wrong
3017 current_inferior
= NULL
;
3021 /* Set a valid thread as current. */
3022 set_desired_inferior (0);
3027 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3028 move it out, because we need to report the stop event to GDB. For
3029 example, if the user puts a breakpoint in the jump pad, it's
3030 because she wants to debug it. */
3033 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3035 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3036 struct thread_info
*thread
= get_lwp_thread (lwp
);
3038 gdb_assert (lwp
->suspended
== 0);
3039 gdb_assert (lwp
->stopped
);
3041 /* Allow debugging the jump pad, gdb_collect, etc.. */
3042 return (supports_fast_tracepoints ()
3043 && agent_loaded_p ()
3044 && (gdb_breakpoint_here (lwp
->stop_pc
)
3045 || lwp
->stopped_by_watchpoint
3046 || thread
->last_resume_kind
== resume_step
)
3047 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3051 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3053 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3054 struct thread_info
*thread
= get_lwp_thread (lwp
);
3057 gdb_assert (lwp
->suspended
== 0);
3058 gdb_assert (lwp
->stopped
);
3060 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3062 /* Allow debugging the jump pad, gdb_collect, etc. */
3063 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3064 && !lwp
->stopped_by_watchpoint
3065 && thread
->last_resume_kind
!= resume_step
3066 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3070 "LWP %ld needs stabilizing (in jump pad)\n",
3075 lwp
->status_pending_p
= 0;
3076 enqueue_one_deferred_signal (lwp
, wstat
);
3080 "Signal %d for LWP %ld deferred "
3082 WSTOPSIG (*wstat
), lwpid_of (lwp
));
3085 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3092 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3094 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3103 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3104 If SUSPEND, then also increase the suspend count of every LWP,
3108 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3110 /* Should not be called recursively. */
3111 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3113 stopping_threads
= (suspend
3114 ? STOPPING_AND_SUSPENDING_THREADS
3115 : STOPPING_THREADS
);
3118 find_inferior (&all_lwps
, suspend_and_send_sigstop_callback
, except
);
3120 find_inferior (&all_lwps
, send_sigstop_callback
, except
);
3121 for_each_inferior (&all_lwps
, wait_for_sigstop
);
3122 stopping_threads
= NOT_STOPPING_THREADS
;
3125 /* Resume execution of the inferior process.
3126 If STEP is nonzero, single-step it.
3127 If SIGNAL is nonzero, give it that signal. */
3130 linux_resume_one_lwp (struct lwp_info
*lwp
,
3131 int step
, int signal
, siginfo_t
*info
)
3133 struct thread_info
*saved_inferior
;
3134 int fast_tp_collecting
;
3136 if (lwp
->stopped
== 0)
3139 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3141 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3143 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3144 user used the "jump" command, or "set $pc = foo"). */
3145 if (lwp
->stop_pc
!= get_pc (lwp
))
3147 /* Collecting 'while-stepping' actions doesn't make sense
3149 release_while_stepping_state_list (get_lwp_thread (lwp
));
3152 /* If we have pending signals or status, and a new signal, enqueue the
3153 signal. Also enqueue the signal if we are waiting to reinsert a
3154 breakpoint; it will be picked up again below. */
3156 && (lwp
->status_pending_p
3157 || lwp
->pending_signals
!= NULL
3158 || lwp
->bp_reinsert
!= 0
3159 || fast_tp_collecting
))
3161 struct pending_signals
*p_sig
;
3162 p_sig
= xmalloc (sizeof (*p_sig
));
3163 p_sig
->prev
= lwp
->pending_signals
;
3164 p_sig
->signal
= signal
;
3166 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3168 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3169 lwp
->pending_signals
= p_sig
;
3172 if (lwp
->status_pending_p
)
3175 fprintf (stderr
, "Not resuming lwp %ld (%s, signal %d, stop %s);"
3176 " has pending status\n",
3177 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3178 lwp
->stop_expected
? "expected" : "not expected");
3182 saved_inferior
= current_inferior
;
3183 current_inferior
= get_lwp_thread (lwp
);
3186 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
3187 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3188 lwp
->stop_expected
? "expected" : "not expected");
3190 /* This bit needs some thinking about. If we get a signal that
3191 we must report while a single-step reinsert is still pending,
3192 we often end up resuming the thread. It might be better to
3193 (ew) allow a stack of pending events; then we could be sure that
3194 the reinsert happened right away and not lose any signals.
3196 Making this stack would also shrink the window in which breakpoints are
3197 uninserted (see comment in linux_wait_for_lwp) but not enough for
3198 complete correctness, so it won't solve that problem. It may be
3199 worthwhile just to solve this one, however. */
3200 if (lwp
->bp_reinsert
!= 0)
3203 fprintf (stderr
, " pending reinsert at 0x%s\n",
3204 paddress (lwp
->bp_reinsert
));
3206 if (can_hardware_single_step ())
3208 if (fast_tp_collecting
== 0)
3211 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
3213 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
3220 /* Postpone any pending signal. It was enqueued above. */
3224 if (fast_tp_collecting
== 1)
3228 lwp %ld wants to get out of fast tracepoint jump pad (exit-jump-pad-bkpt)\n",
3231 /* Postpone any pending signal. It was enqueued above. */
3234 else if (fast_tp_collecting
== 2)
3238 lwp %ld wants to get out of fast tracepoint jump pad single-stepping\n",
3241 if (can_hardware_single_step ())
3244 fatal ("moving out of jump pad single-stepping"
3245 " not implemented on this target");
3247 /* Postpone any pending signal. It was enqueued above. */
3251 /* If we have while-stepping actions in this thread set it stepping.
3252 If we have a signal to deliver, it may or may not be set to
3253 SIG_IGN, we don't know. Assume so, and allow collecting
3254 while-stepping into a signal handler. A possible smart thing to
3255 do would be to set an internal breakpoint at the signal return
3256 address, continue, and carry on catching this while-stepping
3257 action only when that breakpoint is hit. A future
3259 if (get_lwp_thread (lwp
)->while_stepping
!= NULL
3260 && can_hardware_single_step ())
3264 "lwp %ld has a while-stepping action -> forcing step.\n",
3269 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
3271 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
3272 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
3273 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
3276 /* If we have pending signals, consume one unless we are trying to
3277 reinsert a breakpoint or we're trying to finish a fast tracepoint
3279 if (lwp
->pending_signals
!= NULL
3280 && lwp
->bp_reinsert
== 0
3281 && fast_tp_collecting
== 0)
3283 struct pending_signals
**p_sig
;
3285 p_sig
= &lwp
->pending_signals
;
3286 while ((*p_sig
)->prev
!= NULL
)
3287 p_sig
= &(*p_sig
)->prev
;
3289 signal
= (*p_sig
)->signal
;
3290 if ((*p_sig
)->info
.si_signo
!= 0)
3291 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), (PTRACE_ARG3_TYPE
) 0,
3298 if (the_low_target
.prepare_to_resume
!= NULL
)
3299 the_low_target
.prepare_to_resume (lwp
);
3301 regcache_invalidate_one ((struct inferior_list_entry
*)
3302 get_lwp_thread (lwp
));
3305 lwp
->stopped_by_watchpoint
= 0;
3306 lwp
->stepping
= step
;
3307 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
),
3308 (PTRACE_ARG3_TYPE
) 0,
3309 /* Coerce to a uintptr_t first to avoid potential gcc warning
3310 of coercing an 8 byte integer to a 4 byte pointer. */
3311 (PTRACE_ARG4_TYPE
) (uintptr_t) signal
);
3313 current_inferior
= saved_inferior
;
3316 /* ESRCH from ptrace either means that the thread was already
3317 running (an error) or that it is gone (a race condition). If
3318 it's gone, we will get a notification the next time we wait,
3319 so we can ignore the error. We could differentiate these
3320 two, but it's tricky without waiting; the thread still exists
3321 as a zombie, so sending it signal 0 would succeed. So just
3326 perror_with_name ("ptrace");
3330 struct thread_resume_array
3332 struct thread_resume
*resume
;
3336 /* This function is called once per thread. We look up the thread
3337 in RESUME_PTR, and mark the thread with a pointer to the appropriate
3340 This algorithm is O(threads * resume elements), but resume elements
3341 is small (and will remain small at least until GDB supports thread
3344 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3346 struct lwp_info
*lwp
;
3347 struct thread_info
*thread
;
3349 struct thread_resume_array
*r
;
3351 thread
= (struct thread_info
*) entry
;
3352 lwp
= get_thread_lwp (thread
);
3355 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3357 ptid_t ptid
= r
->resume
[ndx
].thread
;
3358 if (ptid_equal (ptid
, minus_one_ptid
)
3359 || ptid_equal (ptid
, entry
->id
)
3360 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
3362 || (ptid_get_pid (ptid
) == pid_of (lwp
)
3363 && (ptid_is_pid (ptid
)
3364 || ptid_get_lwp (ptid
) == -1)))
3366 if (r
->resume
[ndx
].kind
== resume_stop
3367 && thread
->last_resume_kind
== resume_stop
)
3370 fprintf (stderr
, "already %s LWP %ld at GDB's request\n",
3371 thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
3379 lwp
->resume
= &r
->resume
[ndx
];
3380 thread
->last_resume_kind
= lwp
->resume
->kind
;
3382 /* If we had a deferred signal to report, dequeue one now.
3383 This can happen if LWP gets more than one signal while
3384 trying to get out of a jump pad. */
3386 && !lwp
->status_pending_p
3387 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3389 lwp
->status_pending_p
= 1;
3393 "Dequeueing deferred signal %d for LWP %ld, "
3394 "leaving status pending.\n",
3395 WSTOPSIG (lwp
->status_pending
), lwpid_of (lwp
));
3402 /* No resume action for this thread. */
3409 /* Set *FLAG_P if this lwp has an interesting status pending. */
3411 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3413 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3415 /* LWPs which will not be resumed are not interesting, because
3416 we might not wait for them next time through linux_wait. */
3417 if (lwp
->resume
== NULL
)
3420 if (lwp
->status_pending_p
)
3421 * (int *) flag_p
= 1;
3426 /* Return 1 if this lwp that GDB wants running is stopped at an
3427 internal breakpoint that we need to step over. It assumes that any
3428 required STOP_PC adjustment has already been propagated to the
3429 inferior's regcache. */
3432 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3434 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3435 struct thread_info
*thread
;
3436 struct thread_info
*saved_inferior
;
3439 /* LWPs which will not be resumed are not interesting, because we
3440 might not wait for them next time through linux_wait. */
3446 "Need step over [LWP %ld]? Ignoring, not stopped\n",
3451 thread
= get_lwp_thread (lwp
);
3453 if (thread
->last_resume_kind
== resume_stop
)
3457 "Need step over [LWP %ld]? Ignoring, should remain stopped\n",
3462 gdb_assert (lwp
->suspended
>= 0);
3468 "Need step over [LWP %ld]? Ignoring, suspended\n",
3473 if (!lwp
->need_step_over
)
3477 "Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
3480 if (lwp
->status_pending_p
)
3484 "Need step over [LWP %ld]? Ignoring, has pending status.\n",
3489 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3493 /* If the PC has changed since we stopped, then don't do anything,
3494 and let the breakpoint/tracepoint be hit. This happens if, for
3495 instance, GDB handled the decr_pc_after_break subtraction itself,
3496 GDB is OOL stepping this thread, or the user has issued a "jump"
3497 command, or poked thread's registers herself. */
3498 if (pc
!= lwp
->stop_pc
)
3502 "Need step over [LWP %ld]? Cancelling, PC was changed. "
3503 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3504 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
3506 lwp
->need_step_over
= 0;
3510 saved_inferior
= current_inferior
;
3511 current_inferior
= thread
;
3513 /* We can only step over breakpoints we know about. */
3514 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3516 /* Don't step over a breakpoint that GDB expects to hit
3517 though. If the condition is being evaluated on the target's side
3518 and it evaluate to false, step over this breakpoint as well. */
3519 if (gdb_breakpoint_here (pc
)
3520 && gdb_condition_true_at_breakpoint (pc
)
3521 && gdb_no_commands_at_breakpoint (pc
))
3525 "Need step over [LWP %ld]? yes, but found"
3526 " GDB breakpoint at 0x%s; skipping step over\n",
3527 lwpid_of (lwp
), paddress (pc
));
3529 current_inferior
= saved_inferior
;
3536 "Need step over [LWP %ld]? yes, "
3537 "found breakpoint at 0x%s\n",
3538 lwpid_of (lwp
), paddress (pc
));
3540 /* We've found an lwp that needs stepping over --- return 1 so
3541 that find_inferior stops looking. */
3542 current_inferior
= saved_inferior
;
3544 /* If the step over is cancelled, this is set again. */
3545 lwp
->need_step_over
= 0;
3550 current_inferior
= saved_inferior
;
3554 "Need step over [LWP %ld]? No, no breakpoint found at 0x%s\n",
3555 lwpid_of (lwp
), paddress (pc
));
3560 /* Start a step-over operation on LWP. When LWP stopped at a
3561 breakpoint, to make progress, we need to remove the breakpoint out
3562 of the way. If we let other threads run while we do that, they may
3563 pass by the breakpoint location and miss hitting it. To avoid
3564 that, a step-over momentarily stops all threads while LWP is
3565 single-stepped while the breakpoint is temporarily uninserted from
3566 the inferior. When the single-step finishes, we reinsert the
3567 breakpoint, and let all threads that are supposed to be running,
3570 On targets that don't support hardware single-step, we don't
3571 currently support full software single-stepping. Instead, we only
3572 support stepping over the thread event breakpoint, by asking the
3573 low target where to place a reinsert breakpoint. Since this
3574 routine assumes the breakpoint being stepped over is a thread event
3575 breakpoint, it usually assumes the return address of the current
3576 function is a good enough place to set the reinsert breakpoint. */
3579 start_step_over (struct lwp_info
*lwp
)
3581 struct thread_info
*saved_inferior
;
3587 "Starting step-over on LWP %ld. Stopping all threads\n",
3590 stop_all_lwps (1, lwp
);
3591 gdb_assert (lwp
->suspended
== 0);
3594 fprintf (stderr
, "Done stopping all threads for step-over.\n");
3596 /* Note, we should always reach here with an already adjusted PC,
3597 either by GDB (if we're resuming due to GDB's request), or by our
3598 caller, if we just finished handling an internal breakpoint GDB
3599 shouldn't care about. */
3602 saved_inferior
= current_inferior
;
3603 current_inferior
= get_lwp_thread (lwp
);
3605 lwp
->bp_reinsert
= pc
;
3606 uninsert_breakpoints_at (pc
);
3607 uninsert_fast_tracepoint_jumps_at (pc
);
3609 if (can_hardware_single_step ())
3615 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3616 set_reinsert_breakpoint (raddr
);
3620 current_inferior
= saved_inferior
;
3622 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3624 /* Require next event from this LWP. */
3625 step_over_bkpt
= lwp
->head
.id
;
3629 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3630 start_step_over, if still there, and delete any reinsert
3631 breakpoints we've set, on non hardware single-step targets. */
3634 finish_step_over (struct lwp_info
*lwp
)
3636 if (lwp
->bp_reinsert
!= 0)
3639 fprintf (stderr
, "Finished step over.\n");
3641 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3642 may be no breakpoint to reinsert there by now. */
3643 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3644 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3646 lwp
->bp_reinsert
= 0;
3648 /* Delete any software-single-step reinsert breakpoints. No
3649 longer needed. We don't have to worry about other threads
3650 hitting this trap, and later not being able to explain it,
3651 because we were stepping over a breakpoint, and we hold all
3652 threads but LWP stopped while doing that. */
3653 if (!can_hardware_single_step ())
3654 delete_reinsert_breakpoints ();
3656 step_over_bkpt
= null_ptid
;
3663 /* This function is called once per thread. We check the thread's resume
3664 request, which will tell us whether to resume, step, or leave the thread
3665 stopped; and what signal, if any, it should be sent.
3667 For threads which we aren't explicitly told otherwise, we preserve
3668 the stepping flag; this is used for stepping over gdbserver-placed
3671 If pending_flags was set in any thread, we queue any needed
3672 signals, since we won't actually resume. We already have a pending
3673 event to report, so we don't need to preserve any step requests;
3674 they should be re-issued if necessary. */
3677 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3679 struct lwp_info
*lwp
;
3680 struct thread_info
*thread
;
3682 int leave_all_stopped
= * (int *) arg
;
3685 thread
= (struct thread_info
*) entry
;
3686 lwp
= get_thread_lwp (thread
);
3688 if (lwp
->resume
== NULL
)
3691 if (lwp
->resume
->kind
== resume_stop
)
3694 fprintf (stderr
, "resume_stop request for LWP %ld\n", lwpid_of (lwp
));
3699 fprintf (stderr
, "stopping LWP %ld\n", lwpid_of (lwp
));
3701 /* Stop the thread, and wait for the event asynchronously,
3702 through the event loop. */
3708 fprintf (stderr
, "already stopped LWP %ld\n",
3711 /* The LWP may have been stopped in an internal event that
3712 was not meant to be notified back to GDB (e.g., gdbserver
3713 breakpoint), so we should be reporting a stop event in
3716 /* If the thread already has a pending SIGSTOP, this is a
3717 no-op. Otherwise, something later will presumably resume
3718 the thread and this will cause it to cancel any pending
3719 operation, due to last_resume_kind == resume_stop. If
3720 the thread already has a pending status to report, we
3721 will still report it the next time we wait - see
3722 status_pending_p_callback. */
3724 /* If we already have a pending signal to report, then
3725 there's no need to queue a SIGSTOP, as this means we're
3726 midway through moving the LWP out of the jumppad, and we
3727 will report the pending signal as soon as that is
3729 if (lwp
->pending_signals_to_report
== NULL
)
3733 /* For stop requests, we're done. */
3735 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3739 /* If this thread which is about to be resumed has a pending status,
3740 then don't resume any threads - we can just report the pending
3741 status. Make sure to queue any signals that would otherwise be
3742 sent. In all-stop mode, we do this decision based on if *any*
3743 thread has a pending status. If there's a thread that needs the
3744 step-over-breakpoint dance, then don't resume any other thread
3745 but that particular one. */
3746 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
3751 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
3753 step
= (lwp
->resume
->kind
== resume_step
);
3754 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
3759 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
3761 /* If we have a new signal, enqueue the signal. */
3762 if (lwp
->resume
->sig
!= 0)
3764 struct pending_signals
*p_sig
;
3765 p_sig
= xmalloc (sizeof (*p_sig
));
3766 p_sig
->prev
= lwp
->pending_signals
;
3767 p_sig
->signal
= lwp
->resume
->sig
;
3768 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3770 /* If this is the same signal we were previously stopped by,
3771 make sure to queue its siginfo. We can ignore the return
3772 value of ptrace; if it fails, we'll skip
3773 PTRACE_SETSIGINFO. */
3774 if (WIFSTOPPED (lwp
->last_status
)
3775 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
3776 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), (PTRACE_ARG3_TYPE
) 0,
3779 lwp
->pending_signals
= p_sig
;
3783 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3789 linux_resume (struct thread_resume
*resume_info
, size_t n
)
3791 struct thread_resume_array array
= { resume_info
, n
};
3792 struct lwp_info
*need_step_over
= NULL
;
3794 int leave_all_stopped
;
3796 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
3798 /* If there is a thread which would otherwise be resumed, which has
3799 a pending status, then don't resume any threads - we can just
3800 report the pending status. Make sure to queue any signals that
3801 would otherwise be sent. In non-stop mode, we'll apply this
3802 logic to each thread individually. We consume all pending events
3803 before considering to start a step-over (in all-stop). */
3806 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
3808 /* If there is a thread which would otherwise be resumed, which is
3809 stopped at a breakpoint that needs stepping over, then don't
3810 resume any threads - have it step over the breakpoint with all
3811 other threads stopped, then resume all threads again. Make sure
3812 to queue any signals that would otherwise be delivered or
3814 if (!any_pending
&& supports_breakpoints ())
3816 = (struct lwp_info
*) find_inferior (&all_lwps
,
3817 need_step_over_p
, NULL
);
3819 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
3823 if (need_step_over
!= NULL
)
3824 fprintf (stderr
, "Not resuming all, need step over\n");
3825 else if (any_pending
)
3827 "Not resuming, all-stop and found "
3828 "an LWP with pending status\n");
3830 fprintf (stderr
, "Resuming, no pending status or step over needed\n");
3833 /* Even if we're leaving threads stopped, queue all signals we'd
3834 otherwise deliver. */
3835 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
3838 start_step_over (need_step_over
);
3841 /* This function is called once per thread. We check the thread's
3842 last resume request, which will tell us whether to resume, step, or
3843 leave the thread stopped. Any signal the client requested to be
3844 delivered has already been enqueued at this point.
3846 If any thread that GDB wants running is stopped at an internal
3847 breakpoint that needs stepping over, we start a step-over operation
3848 on that particular thread, and leave all others stopped. */
3851 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3853 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3854 struct thread_info
*thread
;
3862 "proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
3867 fprintf (stderr
, " LWP %ld already running\n", lwpid_of (lwp
));
3871 thread
= get_lwp_thread (lwp
);
3873 if (thread
->last_resume_kind
== resume_stop
3874 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
3877 fprintf (stderr
, " client wants LWP to remain %ld stopped\n",
3882 if (lwp
->status_pending_p
)
3885 fprintf (stderr
, " LWP %ld has pending status, leaving stopped\n",
3890 gdb_assert (lwp
->suspended
>= 0);
3895 fprintf (stderr
, " LWP %ld is suspended\n", lwpid_of (lwp
));
3899 if (thread
->last_resume_kind
== resume_stop
3900 && lwp
->pending_signals_to_report
== NULL
3901 && lwp
->collecting_fast_tracepoint
== 0)
3903 /* We haven't reported this LWP as stopped yet (otherwise, the
3904 last_status.kind check above would catch it, and we wouldn't
3905 reach here. This LWP may have been momentarily paused by a
3906 stop_all_lwps call while handling for example, another LWP's
3907 step-over. In that case, the pending expected SIGSTOP signal
3908 that was queued at vCont;t handling time will have already
3909 been consumed by wait_for_sigstop, and so we need to requeue
3910 another one here. Note that if the LWP already has a SIGSTOP
3911 pending, this is a no-op. */
3915 "Client wants LWP %ld to stop. "
3916 "Making sure it has a SIGSTOP pending\n",
3922 step
= thread
->last_resume_kind
== resume_step
;
3923 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3928 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3930 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3936 gdb_assert (lwp
->suspended
>= 0);
3938 return proceed_one_lwp (entry
, except
);
3941 /* When we finish a step-over, set threads running again. If there's
3942 another thread that may need a step-over, now's the time to start
3943 it. Eventually, we'll move all threads past their breakpoints. */
3946 proceed_all_lwps (void)
3948 struct lwp_info
*need_step_over
;
3950 /* If there is a thread which would otherwise be resumed, which is
3951 stopped at a breakpoint that needs stepping over, then don't
3952 resume any threads - have it step over the breakpoint with all
3953 other threads stopped, then resume all threads again. */
3955 if (supports_breakpoints ())
3958 = (struct lwp_info
*) find_inferior (&all_lwps
,
3959 need_step_over_p
, NULL
);
3961 if (need_step_over
!= NULL
)
3964 fprintf (stderr
, "proceed_all_lwps: found "
3965 "thread %ld needing a step-over\n",
3966 lwpid_of (need_step_over
));
3968 start_step_over (need_step_over
);
3974 fprintf (stderr
, "Proceeding, no step-over needed\n");
3976 find_inferior (&all_lwps
, proceed_one_lwp
, NULL
);
3979 /* Stopped LWPs that the client wanted to be running, that don't have
3980 pending statuses, are set to run again, except for EXCEPT, if not
3981 NULL. This undoes a stop_all_lwps call. */
3984 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
3990 "unstopping all lwps, except=(LWP %ld)\n", lwpid_of (except
));
3993 "unstopping all lwps\n");
3997 find_inferior (&all_lwps
, unsuspend_and_proceed_one_lwp
, except
);
3999 find_inferior (&all_lwps
, proceed_one_lwp
, except
);
4003 #ifdef HAVE_LINUX_REGSETS
4005 #define use_linux_regsets 1
4008 regsets_fetch_inferior_registers (struct regcache
*regcache
)
4010 struct regset_info
*regset
;
4011 int saw_general_regs
= 0;
4015 regset
= target_regsets
;
4017 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4018 while (regset
->size
>= 0)
4023 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
4029 buf
= xmalloc (regset
->size
);
4031 nt_type
= regset
->nt_type
;
4035 iov
.iov_len
= regset
->size
;
4036 data
= (void *) &iov
;
4042 res
= ptrace (regset
->get_request
, pid
,
4043 (PTRACE_ARG3_TYPE
) (long) nt_type
, data
);
4045 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4051 /* If we get EIO on a regset, do not try it again for
4053 disabled_regsets
[regset
- target_regsets
] = 1;
4060 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4065 else if (regset
->type
== GENERAL_REGS
)
4066 saw_general_regs
= 1;
4067 regset
->store_function (regcache
, buf
);
4071 if (saw_general_regs
)
4078 regsets_store_inferior_registers (struct regcache
*regcache
)
4080 struct regset_info
*regset
;
4081 int saw_general_regs
= 0;
4085 regset
= target_regsets
;
4087 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4088 while (regset
->size
>= 0)
4093 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
4099 buf
= xmalloc (regset
->size
);
4101 /* First fill the buffer with the current register set contents,
4102 in case there are any items in the kernel's regset that are
4103 not in gdbserver's regcache. */
4105 nt_type
= regset
->nt_type
;
4109 iov
.iov_len
= regset
->size
;
4110 data
= (void *) &iov
;
4116 res
= ptrace (regset
->get_request
, pid
,
4117 (PTRACE_ARG3_TYPE
) (long) nt_type
, data
);
4119 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4124 /* Then overlay our cached registers on that. */
4125 regset
->fill_function (regcache
, buf
);
4127 /* Only now do we write the register set. */
4129 res
= ptrace (regset
->set_request
, pid
,
4130 (PTRACE_ARG3_TYPE
) (long) nt_type
, data
);
4132 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4140 /* If we get EIO on a regset, do not try it again for
4142 disabled_regsets
[regset
- target_regsets
] = 1;
4146 else if (errno
== ESRCH
)
4148 /* At this point, ESRCH should mean the process is
4149 already gone, in which case we simply ignore attempts
4150 to change its registers. See also the related
4151 comment in linux_resume_one_lwp. */
4157 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4160 else if (regset
->type
== GENERAL_REGS
)
4161 saw_general_regs
= 1;
4165 if (saw_general_regs
)
4171 #else /* !HAVE_LINUX_REGSETS */
4173 #define use_linux_regsets 0
4174 #define regsets_fetch_inferior_registers(regcache) 1
4175 #define regsets_store_inferior_registers(regcache) 1
4179 /* Return 1 if register REGNO is supported by one of the regset ptrace
4180 calls or 0 if it has to be transferred individually. */
4183 linux_register_in_regsets (int regno
)
4185 unsigned char mask
= 1 << (regno
% 8);
4186 size_t index
= regno
/ 8;
4188 return (use_linux_regsets
4189 && (the_low_target
.regset_bitmap
== NULL
4190 || (the_low_target
.regset_bitmap
[index
] & mask
) != 0));
4193 #ifdef HAVE_LINUX_USRREGS
4196 register_addr (int regnum
)
4200 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
4201 error ("Invalid register number %d.", regnum
);
4203 addr
= the_low_target
.regmap
[regnum
];
4208 /* Fetch one register. */
4210 fetch_register (struct regcache
*regcache
, int regno
)
4217 if (regno
>= the_low_target
.num_regs
)
4219 if ((*the_low_target
.cannot_fetch_register
) (regno
))
4222 regaddr
= register_addr (regno
);
4226 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4227 & -sizeof (PTRACE_XFER_TYPE
));
4228 buf
= alloca (size
);
4230 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4231 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4234 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
4235 ptrace (PTRACE_PEEKUSER
, pid
,
4236 /* Coerce to a uintptr_t first to avoid potential gcc warning
4237 of coercing an 8 byte integer to a 4 byte pointer. */
4238 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
, (PTRACE_ARG4_TYPE
) 0);
4239 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4241 error ("reading register %d: %s", regno
, strerror (errno
));
4244 if (the_low_target
.supply_ptrace_register
)
4245 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
4247 supply_register (regcache
, regno
, buf
);
4250 /* Store one register. */
4252 store_register (struct regcache
*regcache
, int regno
)
4259 if (regno
>= the_low_target
.num_regs
)
4261 if ((*the_low_target
.cannot_store_register
) (regno
))
4264 regaddr
= register_addr (regno
);
4268 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4269 & -sizeof (PTRACE_XFER_TYPE
));
4270 buf
= alloca (size
);
4271 memset (buf
, 0, size
);
4273 if (the_low_target
.collect_ptrace_register
)
4274 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
4276 collect_register (regcache
, regno
, buf
);
4278 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4279 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4282 ptrace (PTRACE_POKEUSER
, pid
,
4283 /* Coerce to a uintptr_t first to avoid potential gcc warning
4284 about coercing an 8 byte integer to a 4 byte pointer. */
4285 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
,
4286 (PTRACE_ARG4_TYPE
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
4289 /* At this point, ESRCH should mean the process is
4290 already gone, in which case we simply ignore attempts
4291 to change its registers. See also the related
4292 comment in linux_resume_one_lwp. */
4296 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
4297 error ("writing register %d: %s", regno
, strerror (errno
));
4299 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4303 /* Fetch all registers, or just one, from the child process.
4304 If REGNO is -1, do this for all registers, skipping any that are
4305 assumed to have been retrieved by regsets_fetch_inferior_registers,
4306 unless ALL is non-zero.
4307 Otherwise, REGNO specifies which register (so we can save time). */
4309 usr_fetch_inferior_registers (struct regcache
*regcache
, int regno
, int all
)
4313 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4314 if (all
|| !linux_register_in_regsets (regno
))
4315 fetch_register (regcache
, regno
);
4318 fetch_register (regcache
, regno
);
4321 /* Store our register values back into the inferior.
4322 If REGNO is -1, do this for all registers, skipping any that are
4323 assumed to have been saved by regsets_store_inferior_registers,
4324 unless ALL is non-zero.
4325 Otherwise, REGNO specifies which register (so we can save time). */
4327 usr_store_inferior_registers (struct regcache
*regcache
, int regno
, int all
)
4331 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4332 if (all
|| !linux_register_in_regsets (regno
))
4333 store_register (regcache
, regno
);
4336 store_register (regcache
, regno
);
4339 #else /* !HAVE_LINUX_USRREGS */
4341 #define usr_fetch_inferior_registers(regcache, regno, all) do {} while (0)
4342 #define usr_store_inferior_registers(regcache, regno, all) do {} while (0)
4348 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4355 if (the_low_target
.fetch_register
!= NULL
)
4356 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4357 (*the_low_target
.fetch_register
) (regcache
, regno
);
4359 all
= regsets_fetch_inferior_registers (regcache
);
4360 usr_fetch_inferior_registers (regcache
, -1, all
);
4364 if (the_low_target
.fetch_register
!= NULL
4365 && (*the_low_target
.fetch_register
) (regcache
, regno
))
4368 use_regsets
= linux_register_in_regsets (regno
);
4370 all
= regsets_fetch_inferior_registers (regcache
);
4371 if (!use_regsets
|| all
)
4372 usr_fetch_inferior_registers (regcache
, regno
, 1);
4377 linux_store_registers (struct regcache
*regcache
, int regno
)
4384 all
= regsets_store_inferior_registers (regcache
);
4385 usr_store_inferior_registers (regcache
, regno
, all
);
4389 use_regsets
= linux_register_in_regsets (regno
);
4391 all
= regsets_store_inferior_registers (regcache
);
4392 if (!use_regsets
|| all
)
4393 usr_store_inferior_registers (regcache
, regno
, 1);
4398 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4399 to debugger memory starting at MYADDR. */
4402 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4404 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4405 register PTRACE_XFER_TYPE
*buffer
;
4406 register CORE_ADDR addr
;
4413 /* Try using /proc. Don't bother for one word. */
4414 if (len
>= 3 * sizeof (long))
4418 /* We could keep this file open and cache it - possibly one per
4419 thread. That requires some juggling, but is even faster. */
4420 sprintf (filename
, "/proc/%d/mem", pid
);
4421 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4425 /* If pread64 is available, use it. It's faster if the kernel
4426 supports it (only one syscall), and it's 64-bit safe even on
4427 32-bit platforms (for instance, SPARC debugging a SPARC64
4430 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
4433 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
4434 bytes
= read (fd
, myaddr
, len
);
4441 /* Some data was read, we'll try to get the rest with ptrace. */
4451 /* Round starting address down to longword boundary. */
4452 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4453 /* Round ending address up; get number of longwords that makes. */
4454 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4455 / sizeof (PTRACE_XFER_TYPE
));
4456 /* Allocate buffer of that many longwords. */
4457 buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4459 /* Read all the longwords */
4461 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4463 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4464 about coercing an 8 byte integer to a 4 byte pointer. */
4465 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4466 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
4467 (PTRACE_ARG4_TYPE
) 0);
4473 /* Copy appropriate bytes out of the buffer. */
4476 i
*= sizeof (PTRACE_XFER_TYPE
);
4477 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
4479 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4486 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4487 memory at MEMADDR. On failure (cannot write to the inferior)
4488 returns the value of errno. Always succeeds if LEN is zero. */
4491 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4494 /* Round starting address down to longword boundary. */
4495 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4496 /* Round ending address up; get number of longwords that makes. */
4498 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4499 / sizeof (PTRACE_XFER_TYPE
);
4501 /* Allocate buffer of that many longwords. */
4502 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4503 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4505 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4509 /* Zero length write always succeeds. */
4515 /* Dump up to four bytes. */
4516 unsigned int val
= * (unsigned int *) myaddr
;
4522 val
= val
& 0xffffff;
4523 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4524 val
, (long)memaddr
);
4527 /* Fill start and end extra bytes of buffer with existing memory data. */
4530 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4531 about coercing an 8 byte integer to a 4 byte pointer. */
4532 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4533 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
4534 (PTRACE_ARG4_TYPE
) 0);
4542 = ptrace (PTRACE_PEEKTEXT
, pid
,
4543 /* Coerce to a uintptr_t first to avoid potential gcc warning
4544 about coercing an 8 byte integer to a 4 byte pointer. */
4545 (PTRACE_ARG3_TYPE
) (uintptr_t) (addr
+ (count
- 1)
4546 * sizeof (PTRACE_XFER_TYPE
)),
4547 (PTRACE_ARG4_TYPE
) 0);
4552 /* Copy data to be written over corresponding part of buffer. */
4554 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4557 /* Write the entire buffer. */
4559 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4562 ptrace (PTRACE_POKETEXT
, pid
,
4563 /* Coerce to a uintptr_t first to avoid potential gcc warning
4564 about coercing an 8 byte integer to a 4 byte pointer. */
4565 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
4566 (PTRACE_ARG4_TYPE
) buffer
[i
]);
4574 /* Non-zero if the kernel supports PTRACE_O_TRACEFORK. */
4575 static int linux_supports_tracefork_flag
;
4578 linux_enable_event_reporting (int pid
)
4580 if (!linux_supports_tracefork_flag
)
4583 ptrace (PTRACE_SETOPTIONS
, pid
, (PTRACE_ARG3_TYPE
) 0,
4584 (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
4587 /* Helper functions for linux_test_for_tracefork, called via clone (). */
4590 linux_tracefork_grandchild (void *arg
)
4595 #define STACK_SIZE 4096
4598 linux_tracefork_child (void *arg
)
4600 ptrace (PTRACE_TRACEME
, 0, (PTRACE_ARG3_TYPE
) 0, (PTRACE_ARG4_TYPE
) 0);
4601 kill (getpid (), SIGSTOP
);
4603 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4606 linux_tracefork_grandchild (NULL
);
4608 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4611 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
4612 CLONE_VM
| SIGCHLD
, NULL
);
4614 clone (linux_tracefork_grandchild
, (char *) arg
+ STACK_SIZE
,
4615 CLONE_VM
| SIGCHLD
, NULL
);
4618 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4623 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
4624 sure that we can enable the option, and that it had the desired
4628 linux_test_for_tracefork (void)
4630 int child_pid
, ret
, status
;
4632 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4633 char *stack
= xmalloc (STACK_SIZE
* 4);
4634 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4636 linux_supports_tracefork_flag
= 0;
4638 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4640 child_pid
= fork ();
4642 linux_tracefork_child (NULL
);
4644 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4646 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
4648 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
4649 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4650 #else /* !__ia64__ */
4651 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
4652 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4653 #endif /* !__ia64__ */
4655 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4657 if (child_pid
== -1)
4658 perror_with_name ("clone");
4660 ret
= my_waitpid (child_pid
, &status
, 0);
4662 perror_with_name ("waitpid");
4663 else if (ret
!= child_pid
)
4664 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
4665 if (! WIFSTOPPED (status
))
4666 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
4668 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, (PTRACE_ARG3_TYPE
) 0,
4669 (PTRACE_ARG4_TYPE
) PTRACE_O_TRACEFORK
);
4672 ret
= ptrace (PTRACE_KILL
, child_pid
, (PTRACE_ARG3_TYPE
) 0,
4673 (PTRACE_ARG4_TYPE
) 0);
4676 warning ("linux_test_for_tracefork: failed to kill child");
4680 ret
= my_waitpid (child_pid
, &status
, 0);
4681 if (ret
!= child_pid
)
4682 warning ("linux_test_for_tracefork: failed to wait for killed child");
4683 else if (!WIFSIGNALED (status
))
4684 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
4685 "killed child", status
);
4690 ret
= ptrace (PTRACE_CONT
, child_pid
, (PTRACE_ARG3_TYPE
) 0,
4691 (PTRACE_ARG4_TYPE
) 0);
4693 warning ("linux_test_for_tracefork: failed to resume child");
4695 ret
= my_waitpid (child_pid
, &status
, 0);
4697 if (ret
== child_pid
&& WIFSTOPPED (status
)
4698 && status
>> 16 == PTRACE_EVENT_FORK
)
4701 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, (PTRACE_ARG3_TYPE
) 0,
4703 if (ret
== 0 && second_pid
!= 0)
4707 linux_supports_tracefork_flag
= 1;
4708 my_waitpid (second_pid
, &second_status
, 0);
4709 ret
= ptrace (PTRACE_KILL
, second_pid
, (PTRACE_ARG3_TYPE
) 0,
4710 (PTRACE_ARG4_TYPE
) 0);
4712 warning ("linux_test_for_tracefork: failed to kill second child");
4713 my_waitpid (second_pid
, &status
, 0);
4717 warning ("linux_test_for_tracefork: unexpected result from waitpid "
4718 "(%d, status 0x%x)", ret
, status
);
4722 ret
= ptrace (PTRACE_KILL
, child_pid
, (PTRACE_ARG3_TYPE
) 0,
4723 (PTRACE_ARG4_TYPE
) 0);
4725 warning ("linux_test_for_tracefork: failed to kill child");
4726 my_waitpid (child_pid
, &status
, 0);
4728 while (WIFSTOPPED (status
));
4730 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4732 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4737 linux_look_up_symbols (void)
4739 #ifdef USE_THREAD_DB
4740 struct process_info
*proc
= current_process ();
4742 if (proc
->private->thread_db
!= NULL
)
4745 /* If the kernel supports tracing forks then it also supports tracing
4746 clones, and then we don't need to use the magic thread event breakpoint
4747 to learn about threads. */
4748 thread_db_init (!linux_supports_tracefork_flag
);
4753 linux_request_interrupt (void)
4755 extern unsigned long signal_pid
;
4757 if (!ptid_equal (cont_thread
, null_ptid
)
4758 && !ptid_equal (cont_thread
, minus_one_ptid
))
4760 struct lwp_info
*lwp
;
4763 lwp
= get_thread_lwp (current_inferior
);
4764 lwpid
= lwpid_of (lwp
);
4765 kill_lwp (lwpid
, SIGINT
);
4768 kill_lwp (signal_pid
, SIGINT
);
4771 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4772 to debugger memory starting at MYADDR. */
4775 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4777 char filename
[PATH_MAX
];
4779 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4781 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4783 fd
= open (filename
, O_RDONLY
);
4787 if (offset
!= (CORE_ADDR
) 0
4788 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4791 n
= read (fd
, myaddr
, len
);
4798 /* These breakpoint and watchpoint related wrapper functions simply
4799 pass on the function call if the target has registered a
4800 corresponding function. */
4803 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
4805 if (the_low_target
.insert_point
!= NULL
)
4806 return the_low_target
.insert_point (type
, addr
, len
);
4808 /* Unsupported (see target.h). */
4813 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
4815 if (the_low_target
.remove_point
!= NULL
)
4816 return the_low_target
.remove_point (type
, addr
, len
);
4818 /* Unsupported (see target.h). */
4823 linux_stopped_by_watchpoint (void)
4825 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4827 return lwp
->stopped_by_watchpoint
;
4831 linux_stopped_data_address (void)
4833 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4835 return lwp
->stopped_data_address
;
4838 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4839 #if ! (defined(PT_TEXT_ADDR) \
4840 || defined(PT_DATA_ADDR) \
4841 || defined(PT_TEXT_END_ADDR))
4842 #if defined(__mcoldfire__)
4843 /* These should really be defined in the kernel's ptrace.h header. */
4844 #define PT_TEXT_ADDR 49*4
4845 #define PT_DATA_ADDR 50*4
4846 #define PT_TEXT_END_ADDR 51*4
4848 #define PT_TEXT_ADDR 220
4849 #define PT_TEXT_END_ADDR 224
4850 #define PT_DATA_ADDR 228
4851 #elif defined(__TMS320C6X__)
4852 #define PT_TEXT_ADDR (0x10000*4)
4853 #define PT_DATA_ADDR (0x10004*4)
4854 #define PT_TEXT_END_ADDR (0x10008*4)
4858 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4859 to tell gdb about. */
4862 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
4864 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
4865 unsigned long text
, text_end
, data
;
4866 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4870 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_ARG3_TYPE
) PT_TEXT_ADDR
,
4871 (PTRACE_ARG4_TYPE
) 0);
4872 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_ARG3_TYPE
) PT_TEXT_END_ADDR
,
4873 (PTRACE_ARG4_TYPE
) 0);
4874 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_ARG3_TYPE
) PT_DATA_ADDR
,
4875 (PTRACE_ARG4_TYPE
) 0);
4879 /* Both text and data offsets produced at compile-time (and so
4880 used by gdb) are relative to the beginning of the program,
4881 with the data segment immediately following the text segment.
4882 However, the actual runtime layout in memory may put the data
4883 somewhere else, so when we send gdb a data base-address, we
4884 use the real data base address and subtract the compile-time
4885 data base-address from it (which is just the length of the
4886 text segment). BSS immediately follows data in both
4889 *data_p
= data
- (text_end
- text
);
4899 linux_qxfer_osdata (const char *annex
,
4900 unsigned char *readbuf
, unsigned const char *writebuf
,
4901 CORE_ADDR offset
, int len
)
4903 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
4906 /* Convert a native/host siginfo object, into/from the siginfo in the
4907 layout of the inferiors' architecture. */
4910 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
4914 if (the_low_target
.siginfo_fixup
!= NULL
)
4915 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4917 /* If there was no callback, or the callback didn't do anything,
4918 then just do a straight memcpy. */
4922 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
4924 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
4929 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
4930 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
4934 char inf_siginfo
[sizeof (siginfo_t
)];
4936 if (current_inferior
== NULL
)
4939 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4942 fprintf (stderr
, "%s siginfo for lwp %d.\n",
4943 readbuf
!= NULL
? "Reading" : "Writing",
4946 if (offset
>= sizeof (siginfo
))
4949 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_ARG3_TYPE
) 0, &siginfo
) != 0)
4952 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4953 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4954 inferior with a 64-bit GDBSERVER should look the same as debugging it
4955 with a 32-bit GDBSERVER, we need to convert it. */
4956 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4958 if (offset
+ len
> sizeof (siginfo
))
4959 len
= sizeof (siginfo
) - offset
;
4961 if (readbuf
!= NULL
)
4962 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4965 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4967 /* Convert back to ptrace layout before flushing it out. */
4968 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4970 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_ARG3_TYPE
) 0, &siginfo
) != 0)
4977 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4978 so we notice when children change state; as the handler for the
4979 sigsuspend in my_waitpid. */
4982 sigchld_handler (int signo
)
4984 int old_errno
= errno
;
4990 /* fprintf is not async-signal-safe, so call write
4992 if (write (2, "sigchld_handler\n",
4993 sizeof ("sigchld_handler\n") - 1) < 0)
4994 break; /* just ignore */
4998 if (target_is_async_p ())
4999 async_file_mark (); /* trigger a linux_wait */
5005 linux_supports_non_stop (void)
5011 linux_async (int enable
)
5013 int previous
= (linux_event_pipe
[0] != -1);
5016 fprintf (stderr
, "linux_async (%d), previous=%d\n",
5019 if (previous
!= enable
)
5022 sigemptyset (&mask
);
5023 sigaddset (&mask
, SIGCHLD
);
5025 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
5029 if (pipe (linux_event_pipe
) == -1)
5030 fatal ("creating event pipe failed.");
5032 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5033 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5035 /* Register the event loop handler. */
5036 add_file_handler (linux_event_pipe
[0],
5037 handle_target_event
, NULL
);
5039 /* Always trigger a linux_wait. */
5044 delete_file_handler (linux_event_pipe
[0]);
5046 close (linux_event_pipe
[0]);
5047 close (linux_event_pipe
[1]);
5048 linux_event_pipe
[0] = -1;
5049 linux_event_pipe
[1] = -1;
5052 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5059 linux_start_non_stop (int nonstop
)
5061 /* Register or unregister from event-loop accordingly. */
5062 linux_async (nonstop
);
5067 linux_supports_multi_process (void)
5073 linux_supports_disable_randomization (void)
5075 #ifdef HAVE_PERSONALITY
5083 linux_supports_agent (void)
5088 /* Enumerate spufs IDs for process PID. */
5090 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
5096 struct dirent
*entry
;
5098 sprintf (path
, "/proc/%ld/fd", pid
);
5099 dir
= opendir (path
);
5104 while ((entry
= readdir (dir
)) != NULL
)
5110 fd
= atoi (entry
->d_name
);
5114 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
5115 if (stat (path
, &st
) != 0)
5117 if (!S_ISDIR (st
.st_mode
))
5120 if (statfs (path
, &stfs
) != 0)
5122 if (stfs
.f_type
!= SPUFS_MAGIC
)
5125 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
5127 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
5137 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
5138 object type, using the /proc file system. */
5140 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
5141 unsigned const char *writebuf
,
5142 CORE_ADDR offset
, int len
)
5144 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
5149 if (!writebuf
&& !readbuf
)
5157 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5160 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
5161 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5166 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5173 ret
= write (fd
, writebuf
, (size_t) len
);
5175 ret
= read (fd
, readbuf
, (size_t) len
);
5181 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5182 struct target_loadseg
5184 /* Core address to which the segment is mapped. */
5186 /* VMA recorded in the program header. */
5188 /* Size of this segment in memory. */
5192 # if defined PT_GETDSBT
5193 struct target_loadmap
5195 /* Protocol version number, must be zero. */
5197 /* Pointer to the DSBT table, its size, and the DSBT index. */
5198 unsigned *dsbt_table
;
5199 unsigned dsbt_size
, dsbt_index
;
5200 /* Number of segments in this map. */
5202 /* The actual memory map. */
5203 struct target_loadseg segs
[/*nsegs*/];
5205 # define LINUX_LOADMAP PT_GETDSBT
5206 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5207 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5209 struct target_loadmap
5211 /* Protocol version number, must be zero. */
5213 /* Number of segments in this map. */
5215 /* The actual memory map. */
5216 struct target_loadseg segs
[/*nsegs*/];
5218 # define LINUX_LOADMAP PTRACE_GETFDPIC
5219 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5220 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5224 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
5225 unsigned char *myaddr
, unsigned int len
)
5227 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
5229 struct target_loadmap
*data
= NULL
;
5230 unsigned int actual_length
, copy_length
;
5232 if (strcmp (annex
, "exec") == 0)
5233 addr
= (int) LINUX_LOADMAP_EXEC
;
5234 else if (strcmp (annex
, "interp") == 0)
5235 addr
= (int) LINUX_LOADMAP_INTERP
;
5239 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
5245 actual_length
= sizeof (struct target_loadmap
)
5246 + sizeof (struct target_loadseg
) * data
->nsegs
;
5248 if (offset
< 0 || offset
> actual_length
)
5251 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
5252 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
5256 # define linux_read_loadmap NULL
5257 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5260 linux_process_qsupported (const char *query
)
5262 if (the_low_target
.process_qsupported
!= NULL
)
5263 the_low_target
.process_qsupported (query
);
5267 linux_supports_tracepoints (void)
5269 if (*the_low_target
.supports_tracepoints
== NULL
)
5272 return (*the_low_target
.supports_tracepoints
) ();
5276 linux_read_pc (struct regcache
*regcache
)
5278 if (the_low_target
.get_pc
== NULL
)
5281 return (*the_low_target
.get_pc
) (regcache
);
5285 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
5287 gdb_assert (the_low_target
.set_pc
!= NULL
);
5289 (*the_low_target
.set_pc
) (regcache
, pc
);
5293 linux_thread_stopped (struct thread_info
*thread
)
5295 return get_thread_lwp (thread
)->stopped
;
5298 /* This exposes stop-all-threads functionality to other modules. */
5301 linux_pause_all (int freeze
)
5303 stop_all_lwps (freeze
, NULL
);
5306 /* This exposes unstop-all-threads functionality to other gdbserver
5310 linux_unpause_all (int unfreeze
)
5312 unstop_all_lwps (unfreeze
, NULL
);
5316 linux_prepare_to_access_memory (void)
5318 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5321 linux_pause_all (1);
5326 linux_done_accessing_memory (void)
5328 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5331 linux_unpause_all (1);
5335 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5336 CORE_ADDR collector
,
5339 CORE_ADDR
*jump_entry
,
5340 CORE_ADDR
*trampoline
,
5341 ULONGEST
*trampoline_size
,
5342 unsigned char *jjump_pad_insn
,
5343 ULONGEST
*jjump_pad_insn_size
,
5344 CORE_ADDR
*adjusted_insn_addr
,
5345 CORE_ADDR
*adjusted_insn_addr_end
,
5348 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5349 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5350 jump_entry
, trampoline
, trampoline_size
,
5351 jjump_pad_insn
, jjump_pad_insn_size
,
5352 adjusted_insn_addr
, adjusted_insn_addr_end
,
5356 static struct emit_ops
*
5357 linux_emit_ops (void)
5359 if (the_low_target
.emit_ops
!= NULL
)
5360 return (*the_low_target
.emit_ops
) ();
5366 linux_get_min_fast_tracepoint_insn_len (void)
5368 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5371 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5374 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5375 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5377 char filename
[PATH_MAX
];
5379 const int auxv_size
= is_elf64
5380 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5381 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5383 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5385 fd
= open (filename
, O_RDONLY
);
5391 while (read (fd
, buf
, auxv_size
) == auxv_size
5392 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5396 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5398 switch (aux
->a_type
)
5401 *phdr_memaddr
= aux
->a_un
.a_val
;
5404 *num_phdr
= aux
->a_un
.a_val
;
5410 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5412 switch (aux
->a_type
)
5415 *phdr_memaddr
= aux
->a_un
.a_val
;
5418 *num_phdr
= aux
->a_un
.a_val
;
5426 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5428 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5429 "phdr_memaddr = %ld, phdr_num = %d",
5430 (long) *phdr_memaddr
, *num_phdr
);
5437 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5440 get_dynamic (const int pid
, const int is_elf64
)
5442 CORE_ADDR phdr_memaddr
, relocation
;
5444 unsigned char *phdr_buf
;
5445 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5447 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5450 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5451 phdr_buf
= alloca (num_phdr
* phdr_size
);
5453 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5456 /* Compute relocation: it is expected to be 0 for "regular" executables,
5457 non-zero for PIE ones. */
5459 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5462 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5464 if (p
->p_type
== PT_PHDR
)
5465 relocation
= phdr_memaddr
- p
->p_vaddr
;
5469 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5471 if (p
->p_type
== PT_PHDR
)
5472 relocation
= phdr_memaddr
- p
->p_vaddr
;
5475 if (relocation
== -1)
5477 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5478 any real world executables, including PIE executables, have always
5479 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5480 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5481 or present DT_DEBUG anyway (fpc binaries are statically linked).
5483 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5485 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5490 for (i
= 0; i
< num_phdr
; i
++)
5494 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5496 if (p
->p_type
== PT_DYNAMIC
)
5497 return p
->p_vaddr
+ relocation
;
5501 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5503 if (p
->p_type
== PT_DYNAMIC
)
5504 return p
->p_vaddr
+ relocation
;
5511 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5512 can be 0 if the inferior does not yet have the library list initialized.
5513 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
5514 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
5517 get_r_debug (const int pid
, const int is_elf64
)
5519 CORE_ADDR dynamic_memaddr
;
5520 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5521 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5524 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5525 if (dynamic_memaddr
== 0)
5528 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5532 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5533 #ifdef DT_MIPS_RLD_MAP
5537 unsigned char buf
[sizeof (Elf64_Xword
)];
5541 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5543 if (linux_read_memory (dyn
->d_un
.d_val
,
5544 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5549 #endif /* DT_MIPS_RLD_MAP */
5551 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5552 map
= dyn
->d_un
.d_val
;
5554 if (dyn
->d_tag
== DT_NULL
)
5559 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5560 #ifdef DT_MIPS_RLD_MAP
5564 unsigned char buf
[sizeof (Elf32_Word
)];
5568 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5570 if (linux_read_memory (dyn
->d_un
.d_val
,
5571 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5576 #endif /* DT_MIPS_RLD_MAP */
5578 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5579 map
= dyn
->d_un
.d_val
;
5581 if (dyn
->d_tag
== DT_NULL
)
5585 dynamic_memaddr
+= dyn_size
;
5591 /* Read one pointer from MEMADDR in the inferior. */
5594 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5598 /* Go through a union so this works on either big or little endian
5599 hosts, when the inferior's pointer size is smaller than the size
5600 of CORE_ADDR. It is assumed the inferior's endianness is the
5601 same of the superior's. */
5604 CORE_ADDR core_addr
;
5609 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
5612 if (ptr_size
== sizeof (CORE_ADDR
))
5613 *ptr
= addr
.core_addr
;
5614 else if (ptr_size
== sizeof (unsigned int))
5617 gdb_assert_not_reached ("unhandled pointer size");
5622 struct link_map_offsets
5624 /* Offset and size of r_debug.r_version. */
5625 int r_version_offset
;
5627 /* Offset and size of r_debug.r_map. */
5630 /* Offset to l_addr field in struct link_map. */
5633 /* Offset to l_name field in struct link_map. */
5636 /* Offset to l_ld field in struct link_map. */
5639 /* Offset to l_next field in struct link_map. */
5642 /* Offset to l_prev field in struct link_map. */
5646 /* Construct qXfer:libraries-svr4:read reply. */
5649 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5650 unsigned const char *writebuf
,
5651 CORE_ADDR offset
, int len
)
5654 unsigned document_len
;
5655 struct process_info_private
*const priv
= current_process ()->private;
5656 char filename
[PATH_MAX
];
5659 static const struct link_map_offsets lmo_32bit_offsets
=
5661 0, /* r_version offset. */
5662 4, /* r_debug.r_map offset. */
5663 0, /* l_addr offset in link_map. */
5664 4, /* l_name offset in link_map. */
5665 8, /* l_ld offset in link_map. */
5666 12, /* l_next offset in link_map. */
5667 16 /* l_prev offset in link_map. */
5670 static const struct link_map_offsets lmo_64bit_offsets
=
5672 0, /* r_version offset. */
5673 8, /* r_debug.r_map offset. */
5674 0, /* l_addr offset in link_map. */
5675 8, /* l_name offset in link_map. */
5676 16, /* l_ld offset in link_map. */
5677 24, /* l_next offset in link_map. */
5678 32 /* l_prev offset in link_map. */
5680 const struct link_map_offsets
*lmo
;
5681 unsigned int machine
;
5683 if (writebuf
!= NULL
)
5685 if (readbuf
== NULL
)
5688 pid
= lwpid_of (get_thread_lwp (current_inferior
));
5689 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5690 is_elf64
= elf_64_file_p (filename
, &machine
);
5691 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5693 if (priv
->r_debug
== 0)
5694 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5696 /* We failed to find DT_DEBUG. Such situation will not change for this
5697 inferior - do not retry it. Report it to GDB as E01, see for the reasons
5698 at the GDB solib-svr4.c side. */
5699 if (priv
->r_debug
== (CORE_ADDR
) -1)
5702 if (priv
->r_debug
== 0)
5704 document
= xstrdup ("<library-list-svr4 version=\"1.0\"/>\n");
5708 int allocated
= 1024;
5710 const int ptr_size
= is_elf64
? 8 : 4;
5711 CORE_ADDR lm_addr
, lm_prev
, l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5712 int r_version
, header_done
= 0;
5714 document
= xmalloc (allocated
);
5715 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5716 p
= document
+ strlen (document
);
5719 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5720 (unsigned char *) &r_version
,
5721 sizeof (r_version
)) != 0
5724 warning ("unexpected r_debug version %d", r_version
);
5728 if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5729 &lm_addr
, ptr_size
) != 0)
5731 warning ("unable to read r_map from 0x%lx",
5732 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5737 while (read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5738 &l_name
, ptr_size
) == 0
5739 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5740 &l_addr
, ptr_size
) == 0
5741 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5742 &l_ld
, ptr_size
) == 0
5743 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5744 &l_prev
, ptr_size
) == 0
5745 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5746 &l_next
, ptr_size
) == 0)
5748 unsigned char libname
[PATH_MAX
];
5750 if (lm_prev
!= l_prev
)
5752 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5753 (long) lm_prev
, (long) l_prev
);
5757 /* Not checking for error because reading may stop before
5758 we've got PATH_MAX worth of characters. */
5760 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5761 libname
[sizeof (libname
) - 1] = '\0';
5762 if (libname
[0] != '\0')
5764 /* 6x the size for xml_escape_text below. */
5765 size_t len
= 6 * strlen ((char *) libname
);
5770 /* Terminate `<library-list-svr4'. */
5775 while (allocated
< p
- document
+ len
+ 200)
5777 /* Expand to guarantee sufficient storage. */
5778 uintptr_t document_len
= p
- document
;
5780 document
= xrealloc (document
, 2 * allocated
);
5782 p
= document
+ document_len
;
5785 name
= xml_escape_text ((char *) libname
);
5786 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
5787 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5788 name
, (unsigned long) lm_addr
,
5789 (unsigned long) l_addr
, (unsigned long) l_ld
);
5792 else if (lm_prev
== 0)
5794 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5807 /* Empty list; terminate `<library-list-svr4'. */
5811 strcpy (p
, "</library-list-svr4>");
5814 document_len
= strlen (document
);
5815 if (offset
< document_len
)
5816 document_len
-= offset
;
5819 if (len
> document_len
)
5822 memcpy (readbuf
, document
+ offset
, len
);
5828 #ifdef HAVE_LINUX_BTRACE
5830 /* Enable branch tracing. */
5832 static struct btrace_target_info
*
5833 linux_low_enable_btrace (ptid_t ptid
)
5835 struct btrace_target_info
*tinfo
;
5837 tinfo
= linux_enable_btrace (ptid
);
5839 tinfo
->ptr_bits
= register_size (0) * 8;
5844 /* Read branch trace data as btrace xml document. */
5847 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
5850 VEC (btrace_block_s
) *btrace
;
5851 struct btrace_block
*block
;
5854 btrace
= linux_read_btrace (tinfo
, type
);
5856 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
5857 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
5859 for (i
= 0; VEC_iterate (btrace_block_s
, btrace
, i
, block
); i
++)
5860 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
5861 paddress (block
->begin
), paddress (block
->end
));
5863 buffer_grow_str (buffer
, "</btrace>\n");
5865 VEC_free (btrace_block_s
, btrace
);
5867 #endif /* HAVE_LINUX_BTRACE */
5869 static struct target_ops linux_target_ops
= {
5870 linux_create_inferior
,
5879 linux_fetch_registers
,
5880 linux_store_registers
,
5881 linux_prepare_to_access_memory
,
5882 linux_done_accessing_memory
,
5885 linux_look_up_symbols
,
5886 linux_request_interrupt
,
5890 linux_stopped_by_watchpoint
,
5891 linux_stopped_data_address
,
5892 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
5897 #ifdef USE_THREAD_DB
5898 thread_db_get_tls_address
,
5903 hostio_last_error_from_errno
,
5906 linux_supports_non_stop
,
5908 linux_start_non_stop
,
5909 linux_supports_multi_process
,
5910 #ifdef USE_THREAD_DB
5911 thread_db_handle_monitor_command
,
5915 linux_common_core_of_thread
,
5917 linux_process_qsupported
,
5918 linux_supports_tracepoints
,
5921 linux_thread_stopped
,
5925 linux_cancel_breakpoints
,
5926 linux_stabilize_threads
,
5927 linux_install_fast_tracepoint_jump_pad
,
5929 linux_supports_disable_randomization
,
5930 linux_get_min_fast_tracepoint_insn_len
,
5931 linux_qxfer_libraries_svr4
,
5932 linux_supports_agent
,
5933 #ifdef HAVE_LINUX_BTRACE
5934 linux_supports_btrace
,
5935 linux_low_enable_btrace
,
5936 linux_disable_btrace
,
5937 linux_low_read_btrace
,
5947 linux_init_signals ()
5949 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5950 to find what the cancel signal actually is. */
5951 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
5952 signal (__SIGRTMIN
+1, SIG_IGN
);
5957 initialize_low (void)
5959 struct sigaction sigchld_action
;
5960 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
5961 set_target_ops (&linux_target_ops
);
5962 set_breakpoint_data (the_low_target
.breakpoint
,
5963 the_low_target
.breakpoint_len
);
5964 linux_init_signals ();
5965 linux_test_for_tracefork ();
5966 linux_ptrace_init_warnings ();
5967 #ifdef HAVE_LINUX_REGSETS
5968 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
5970 disabled_regsets
= xmalloc (num_regsets
);
5973 sigchld_action
.sa_handler
= sigchld_handler
;
5974 sigemptyset (&sigchld_action
.sa_mask
);
5975 sigchld_action
.sa_flags
= SA_RESTART
;
5976 sigaction (SIGCHLD
, &sigchld_action
, NULL
);