1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-1996, 1998-2012 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "linux-osdata.h"
25 #include <sys/param.h>
26 #include <sys/ptrace.h>
27 #include "linux-ptrace.h"
28 #include "linux-procfs.h"
30 #include <sys/ioctl.h>
36 #include <sys/syscall.h>
40 #include <sys/types.h>
46 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
47 then ELFMAG0 will have been defined. If it didn't get included by
48 gdb_proc_service.h then including it will likely introduce a duplicate
49 definition of elf_fpregset_t. */
54 #define SPUFS_MAGIC 0x23c9b64e
57 #ifdef HAVE_PERSONALITY
58 # include <sys/personality.h>
59 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
60 # define ADDR_NO_RANDOMIZE 0x0040000
69 #define W_STOPCODE(sig) ((sig) << 8 | 0x7f)
72 /* This is the kernel's hard limit. Not to be confused with
79 #if !(defined(__UCLIBC_HAS_MMU__) || defined(__ARCH_HAS_MMU__))
84 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
85 representation of the thread ID.
87 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
88 the same as the LWP ID.
90 ``all_processes'' is keyed by the "overall process ID", which
91 GNU/Linux calls tgid, "thread group ID". */
93 struct inferior_list all_lwps
;
95 /* A list of all unknown processes which receive stop signals. Some other
96 process will presumably claim each of these as forked children
99 struct inferior_list stopped_pids
;
101 /* FIXME this is a bit of a hack, and could be removed. */
102 int stopping_threads
;
104 /* FIXME make into a target method? */
105 int using_threads
= 1;
107 /* True if we're presently stabilizing threads (moving them out of
109 static int stabilizing_threads
;
111 /* This flag is true iff we've just created or attached to our first
112 inferior but it has not stopped yet. As soon as it does, we need
113 to call the low target's arch_setup callback. Doing this only on
114 the first inferior avoids reinializing the architecture on every
115 inferior, and avoids messing with the register caches of the
116 already running inferiors. NOTE: this assumes all inferiors under
117 control of gdbserver have the same architecture. */
118 static int new_inferior
;
120 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
121 int step
, int signal
, siginfo_t
*info
);
122 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
123 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
124 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
125 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
126 static void *add_lwp (ptid_t ptid
);
127 static int linux_stopped_by_watchpoint (void);
128 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
129 static void proceed_all_lwps (void);
130 static int finish_step_over (struct lwp_info
*lwp
);
131 static CORE_ADDR
get_stop_pc (struct lwp_info
*lwp
);
132 static int kill_lwp (unsigned long lwpid
, int signo
);
133 static void linux_enable_event_reporting (int pid
);
135 /* True if the low target can hardware single-step. Such targets
136 don't need a BREAKPOINT_REINSERT_ADDR callback. */
139 can_hardware_single_step (void)
141 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
144 /* True if the low target supports memory breakpoints. If so, we'll
145 have a GET_PC implementation. */
148 supports_breakpoints (void)
150 return (the_low_target
.get_pc
!= NULL
);
153 /* Returns true if this target can support fast tracepoints. This
154 does not mean that the in-process agent has been loaded in the
158 supports_fast_tracepoints (void)
160 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
163 struct pending_signals
167 struct pending_signals
*prev
;
170 #define PTRACE_ARG3_TYPE void *
171 #define PTRACE_ARG4_TYPE void *
172 #define PTRACE_XFER_TYPE long
174 #ifdef HAVE_LINUX_REGSETS
175 static char *disabled_regsets
;
176 static int num_regsets
;
179 /* The read/write ends of the pipe registered as waitable file in the
181 static int linux_event_pipe
[2] = { -1, -1 };
183 /* True if we're currently in async mode. */
184 #define target_is_async_p() (linux_event_pipe[0] != -1)
186 static void send_sigstop (struct lwp_info
*lwp
);
187 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
189 /* Accepts an integer PID; Returns a string representing a file that
190 can be opened to get info for the child process.
191 Space for the result is malloc'd, caller must free. */
194 linux_child_pid_to_exec_file (int pid
)
198 name1
= xmalloc (MAXPATHLEN
);
199 name2
= xmalloc (MAXPATHLEN
);
200 memset (name2
, 0, MAXPATHLEN
);
202 sprintf (name1
, "/proc/%d/exe", pid
);
203 if (readlink (name1
, name2
, MAXPATHLEN
) > 0)
215 /* Return non-zero if HEADER is a 64-bit ELF file. */
218 elf_64_header_p (const Elf64_Ehdr
*header
)
220 return (header
->e_ident
[EI_MAG0
] == ELFMAG0
221 && header
->e_ident
[EI_MAG1
] == ELFMAG1
222 && header
->e_ident
[EI_MAG2
] == ELFMAG2
223 && header
->e_ident
[EI_MAG3
] == ELFMAG3
224 && header
->e_ident
[EI_CLASS
] == ELFCLASS64
);
227 /* Return non-zero if FILE is a 64-bit ELF file,
228 zero if the file is not a 64-bit ELF file,
229 and -1 if the file is not accessible or doesn't exist. */
232 elf_64_file_p (const char *file
)
237 fd
= open (file
, O_RDONLY
);
241 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
248 return elf_64_header_p (&header
);
252 delete_lwp (struct lwp_info
*lwp
)
254 remove_thread (get_lwp_thread (lwp
));
255 remove_inferior (&all_lwps
, &lwp
->head
);
256 free (lwp
->arch_private
);
260 /* Add a process to the common process list, and set its private
263 static struct process_info
*
264 linux_add_process (int pid
, int attached
)
266 struct process_info
*proc
;
268 /* Is this the first process? If so, then set the arch. */
269 if (all_processes
.head
== NULL
)
272 proc
= add_process (pid
, attached
);
273 proc
->private = xcalloc (1, sizeof (*proc
->private));
275 if (the_low_target
.new_process
!= NULL
)
276 proc
->private->arch_private
= the_low_target
.new_process ();
281 /* Wrapper function for waitpid which handles EINTR, and emulates
282 __WALL for systems where that is not available. */
285 my_waitpid (int pid
, int *status
, int flags
)
290 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
294 sigset_t block_mask
, org_mask
, wake_mask
;
297 wnohang
= (flags
& WNOHANG
) != 0;
298 flags
&= ~(__WALL
| __WCLONE
);
301 /* Block all signals while here. This avoids knowing about
302 LinuxThread's signals. */
303 sigfillset (&block_mask
);
304 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
306 /* ... except during the sigsuspend below. */
307 sigemptyset (&wake_mask
);
311 /* Since all signals are blocked, there's no need to check
313 ret
= waitpid (pid
, status
, flags
);
316 if (ret
== -1 && out_errno
!= ECHILD
)
321 if (flags
& __WCLONE
)
323 /* We've tried both flavors now. If WNOHANG is set,
324 there's nothing else to do, just bail out. */
329 fprintf (stderr
, "blocking\n");
331 /* Block waiting for signals. */
332 sigsuspend (&wake_mask
);
338 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
343 ret
= waitpid (pid
, status
, flags
);
344 while (ret
== -1 && errno
== EINTR
);
349 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
350 pid
, flags
, status
? *status
: -1, ret
);
356 /* Handle a GNU/Linux extended wait response. If we see a clone
357 event, we need to add the new LWP to our list (and not report the
358 trap to higher layers). */
361 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
363 int event
= wstat
>> 16;
364 struct lwp_info
*new_lwp
;
366 if (event
== PTRACE_EVENT_CLONE
)
369 unsigned long new_pid
;
370 int ret
, status
= W_STOPCODE (SIGSTOP
);
372 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), 0, &new_pid
);
374 /* If we haven't already seen the new PID stop, wait for it now. */
375 if (! pull_pid_from_list (&stopped_pids
, new_pid
))
377 /* The new child has a pending SIGSTOP. We can't affect it until it
378 hits the SIGSTOP, but we're already attached. */
380 ret
= my_waitpid (new_pid
, &status
, __WALL
);
383 perror_with_name ("waiting for new child");
384 else if (ret
!= new_pid
)
385 warning ("wait returned unexpected PID %d", ret
);
386 else if (!WIFSTOPPED (status
))
387 warning ("wait returned unexpected status 0x%x", status
);
390 linux_enable_event_reporting (new_pid
);
392 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
393 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
394 add_thread (ptid
, new_lwp
);
396 /* Either we're going to immediately resume the new thread
397 or leave it stopped. linux_resume_one_lwp is a nop if it
398 thinks the thread is currently running, so set this first
399 before calling linux_resume_one_lwp. */
400 new_lwp
->stopped
= 1;
402 /* Normally we will get the pending SIGSTOP. But in some cases
403 we might get another signal delivered to the group first.
404 If we do get another signal, be sure not to lose it. */
405 if (WSTOPSIG (status
) == SIGSTOP
)
407 if (stopping_threads
)
408 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
410 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
414 new_lwp
->stop_expected
= 1;
416 if (stopping_threads
)
418 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
419 new_lwp
->status_pending_p
= 1;
420 new_lwp
->status_pending
= status
;
423 /* Pass the signal on. This is what GDB does - except
424 shouldn't we really report it instead? */
425 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
428 /* Always resume the current thread. If we are stopping
429 threads, it will have a pending SIGSTOP; we may as well
431 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
435 /* Return the PC as read from the regcache of LWP, without any
439 get_pc (struct lwp_info
*lwp
)
441 struct thread_info
*saved_inferior
;
442 struct regcache
*regcache
;
445 if (the_low_target
.get_pc
== NULL
)
448 saved_inferior
= current_inferior
;
449 current_inferior
= get_lwp_thread (lwp
);
451 regcache
= get_thread_regcache (current_inferior
, 1);
452 pc
= (*the_low_target
.get_pc
) (regcache
);
455 fprintf (stderr
, "pc is 0x%lx\n", (long) pc
);
457 current_inferior
= saved_inferior
;
461 /* This function should only be called if LWP got a SIGTRAP.
462 The SIGTRAP could mean several things.
464 On i386, where decr_pc_after_break is non-zero:
465 If we were single-stepping this process using PTRACE_SINGLESTEP,
466 we will get only the one SIGTRAP (even if the instruction we
467 stepped over was a breakpoint). The value of $eip will be the
469 If we continue the process using PTRACE_CONT, we will get a
470 SIGTRAP when we hit a breakpoint. The value of $eip will be
471 the instruction after the breakpoint (i.e. needs to be
472 decremented). If we report the SIGTRAP to GDB, we must also
473 report the undecremented PC. If we cancel the SIGTRAP, we
474 must resume at the decremented PC.
476 (Presumably, not yet tested) On a non-decr_pc_after_break machine
477 with hardware or kernel single-step:
478 If we single-step over a breakpoint instruction, our PC will
479 point at the following instruction. If we continue and hit a
480 breakpoint instruction, our PC will point at the breakpoint
484 get_stop_pc (struct lwp_info
*lwp
)
488 if (the_low_target
.get_pc
== NULL
)
491 stop_pc
= get_pc (lwp
);
493 if (WSTOPSIG (lwp
->last_status
) == SIGTRAP
495 && !lwp
->stopped_by_watchpoint
496 && lwp
->last_status
>> 16 == 0)
497 stop_pc
-= the_low_target
.decr_pc_after_break
;
500 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
506 add_lwp (ptid_t ptid
)
508 struct lwp_info
*lwp
;
510 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
511 memset (lwp
, 0, sizeof (*lwp
));
515 if (the_low_target
.new_thread
!= NULL
)
516 lwp
->arch_private
= the_low_target
.new_thread ();
518 add_inferior_to_list (&all_lwps
, &lwp
->head
);
523 /* Start an inferior process and returns its pid.
524 ALLARGS is a vector of program-name and args. */
527 linux_create_inferior (char *program
, char **allargs
)
529 #ifdef HAVE_PERSONALITY
530 int personality_orig
= 0, personality_set
= 0;
532 struct lwp_info
*new_lwp
;
536 #ifdef HAVE_PERSONALITY
537 if (disable_randomization
)
540 personality_orig
= personality (0xffffffff);
541 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
544 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
546 if (errno
!= 0 || (personality_set
547 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
548 warning ("Error disabling address space randomization: %s",
553 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
559 perror_with_name ("fork");
563 ptrace (PTRACE_TRACEME
, 0, 0, 0);
565 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
566 signal (__SIGRTMIN
+ 1, SIG_DFL
);
571 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
572 stdout to stderr so that inferior i/o doesn't corrupt the connection.
573 Also, redirect stdin to /dev/null. */
574 if (remote_connection_is_stdio ())
577 open ("/dev/null", O_RDONLY
);
579 if (write (2, "stdin/stdout redirected\n",
580 sizeof ("stdin/stdout redirected\n") - 1) < 0)
581 /* Errors ignored. */;
584 execv (program
, allargs
);
586 execvp (program
, allargs
);
588 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
594 #ifdef HAVE_PERSONALITY
598 personality (personality_orig
);
600 warning ("Error restoring address space randomization: %s",
605 linux_add_process (pid
, 0);
607 ptid
= ptid_build (pid
, pid
, 0);
608 new_lwp
= add_lwp (ptid
);
609 add_thread (ptid
, new_lwp
);
610 new_lwp
->must_set_ptrace_flags
= 1;
615 /* Attach to an inferior process. */
618 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
621 struct lwp_info
*new_lwp
;
623 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) != 0)
627 /* If we fail to attach to an LWP, just warn. */
628 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
629 strerror (errno
), errno
);
634 /* If we fail to attach to a process, report an error. */
635 error ("Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
636 strerror (errno
), errno
);
640 /* If lwp is the tgid, we handle adding existing threads later.
641 Otherwise we just add lwp without bothering about any other
643 ptid
= ptid_build (lwpid
, lwpid
, 0);
646 /* Note that extracting the pid from the current inferior is
647 safe, since we're always called in the context of the same
648 process as this new thread. */
649 int pid
= pid_of (get_thread_lwp (current_inferior
));
650 ptid
= ptid_build (pid
, lwpid
, 0);
653 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
654 add_thread (ptid
, new_lwp
);
656 /* We need to wait for SIGSTOP before being able to make the next
657 ptrace call on this LWP. */
658 new_lwp
->must_set_ptrace_flags
= 1;
660 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
663 There are several cases to consider here:
665 1) gdbserver has already attached to the process and is being notified
666 of a new thread that is being created.
667 In this case we should ignore that SIGSTOP and resume the
668 process. This is handled below by setting stop_expected = 1,
669 and the fact that add_thread sets last_resume_kind ==
672 2) This is the first thread (the process thread), and we're attaching
673 to it via attach_inferior.
674 In this case we want the process thread to stop.
675 This is handled by having linux_attach set last_resume_kind ==
676 resume_stop after we return.
678 If the pid we are attaching to is also the tgid, we attach to and
679 stop all the existing threads. Otherwise, we attach to pid and
680 ignore any other threads in the same group as this pid.
682 3) GDB is connecting to gdbserver and is requesting an enumeration of all
684 In this case we want the thread to stop.
685 FIXME: This case is currently not properly handled.
686 We should wait for the SIGSTOP but don't. Things work apparently
687 because enough time passes between when we ptrace (ATTACH) and when
688 gdb makes the next ptrace call on the thread.
690 On the other hand, if we are currently trying to stop all threads, we
691 should treat the new thread as if we had sent it a SIGSTOP. This works
692 because we are guaranteed that the add_lwp call above added us to the
693 end of the list, and so the new thread has not yet reached
694 wait_for_sigstop (but will). */
695 new_lwp
->stop_expected
= 1;
699 linux_attach_lwp (unsigned long lwpid
)
701 linux_attach_lwp_1 (lwpid
, 0);
704 /* Attach to PID. If PID is the tgid, attach to it and all
708 linux_attach (unsigned long pid
)
710 /* Attach to PID. We will check for other threads
712 linux_attach_lwp_1 (pid
, 1);
713 linux_add_process (pid
, 1);
717 struct thread_info
*thread
;
719 /* Don't ignore the initial SIGSTOP if we just attached to this
720 process. It will be collected by wait shortly. */
721 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
722 thread
->last_resume_kind
= resume_stop
;
725 if (linux_proc_get_tgid (pid
) == pid
)
730 sprintf (pathname
, "/proc/%ld/task", pid
);
732 dir
= opendir (pathname
);
736 fprintf (stderr
, "Could not open /proc/%ld/task.\n", pid
);
741 /* At this point we attached to the tgid. Scan the task for
744 int new_threads_found
;
748 while (iterations
< 2)
750 new_threads_found
= 0;
751 /* Add all the other threads. While we go through the
752 threads, new threads may be spawned. Cycle through
753 the list of threads until we have done two iterations without
754 finding new threads. */
755 while ((dp
= readdir (dir
)) != NULL
)
758 lwp
= strtoul (dp
->d_name
, NULL
, 10);
760 /* Is this a new thread? */
762 && find_thread_ptid (ptid_build (pid
, lwp
, 0)) == NULL
)
764 linux_attach_lwp_1 (lwp
, 0);
769 Found and attached to new lwp %ld\n", lwp
);
773 if (!new_threads_found
)
794 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
796 struct counter
*counter
= args
;
798 if (ptid_get_pid (entry
->id
) == counter
->pid
)
800 if (++counter
->count
> 1)
808 last_thread_of_process_p (struct thread_info
*thread
)
810 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
811 int pid
= ptid_get_pid (ptid
);
812 struct counter counter
= { pid
, 0 };
814 return (find_inferior (&all_threads
,
815 second_thread_of_pid_p
, &counter
) == NULL
);
818 /* Kill the inferior lwp. */
821 linux_kill_one_lwp (struct inferior_list_entry
*entry
, void *args
)
823 struct thread_info
*thread
= (struct thread_info
*) entry
;
824 struct lwp_info
*lwp
= get_thread_lwp (thread
);
826 int pid
= * (int *) args
;
828 if (ptid_get_pid (entry
->id
) != pid
)
831 /* We avoid killing the first thread here, because of a Linux kernel (at
832 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
833 the children get a chance to be reaped, it will remain a zombie
836 if (lwpid_of (lwp
) == pid
)
839 fprintf (stderr
, "lkop: is last of process %s\n",
840 target_pid_to_str (entry
->id
));
846 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
848 /* Make sure it died. The loop is most likely unnecessary. */
849 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
850 } while (pid
> 0 && WIFSTOPPED (wstat
));
858 struct process_info
*process
;
859 struct lwp_info
*lwp
;
863 process
= find_process_pid (pid
);
867 /* If we're killing a running inferior, make sure it is stopped
868 first, as PTRACE_KILL will not work otherwise. */
869 stop_all_lwps (0, NULL
);
871 find_inferior (&all_threads
, linux_kill_one_lwp
, &pid
);
873 /* See the comment in linux_kill_one_lwp. We did not kill the first
874 thread in the list, so do so now. */
875 lwp
= find_lwp_pid (pid_to_ptid (pid
));
880 fprintf (stderr
, "lk_1: cannot find lwp %ld, for pid: %d\n",
881 lwpid_of (lwp
), pid
);
886 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
887 lwpid_of (lwp
), pid
);
891 ptrace (PTRACE_KILL
, lwpid_of (lwp
), 0, 0);
893 /* Make sure it died. The loop is most likely unnecessary. */
894 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
895 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
898 the_target
->mourn (process
);
900 /* Since we presently can only stop all lwps of all processes, we
901 need to unstop lwps of other processes. */
902 unstop_all_lwps (0, NULL
);
907 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
909 struct thread_info
*thread
= (struct thread_info
*) entry
;
910 struct lwp_info
*lwp
= get_thread_lwp (thread
);
911 int pid
= * (int *) args
;
913 if (ptid_get_pid (entry
->id
) != pid
)
916 /* If this process is stopped but is expecting a SIGSTOP, then make
917 sure we take care of that now. This isn't absolutely guaranteed
918 to collect the SIGSTOP, but is fairly likely to. */
919 if (lwp
->stop_expected
)
922 /* Clear stop_expected, so that the SIGSTOP will be reported. */
923 lwp
->stop_expected
= 0;
924 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
925 linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
928 /* Flush any pending changes to the process's registers. */
929 regcache_invalidate_one ((struct inferior_list_entry
*)
930 get_lwp_thread (lwp
));
932 /* Finally, let it resume. */
933 if (the_low_target
.prepare_to_resume
!= NULL
)
934 the_low_target
.prepare_to_resume (lwp
);
935 ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0, 0);
942 linux_detach (int pid
)
944 struct process_info
*process
;
946 process
= find_process_pid (pid
);
950 /* Stop all threads before detaching. First, ptrace requires that
951 the thread is stopped to sucessfully detach. Second, thread_db
952 may need to uninstall thread event breakpoints from memory, which
953 only works with a stopped process anyway. */
954 stop_all_lwps (0, NULL
);
957 thread_db_detach (process
);
960 /* Stabilize threads (move out of jump pads). */
961 stabilize_threads ();
963 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
965 the_target
->mourn (process
);
967 /* Since we presently can only stop all lwps of all processes, we
968 need to unstop lwps of other processes. */
969 unstop_all_lwps (0, NULL
);
973 /* Remove all LWPs that belong to process PROC from the lwp list. */
976 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
978 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
979 struct process_info
*process
= proc
;
981 if (pid_of (lwp
) == pid_of (process
))
988 linux_mourn (struct process_info
*process
)
990 struct process_info_private
*priv
;
993 thread_db_mourn (process
);
996 find_inferior (&all_lwps
, delete_lwp_callback
, process
);
998 /* Freeing all private data. */
999 priv
= process
->private;
1000 free (priv
->arch_private
);
1002 process
->private = NULL
;
1004 remove_process (process
);
1008 linux_join (int pid
)
1013 ret
= my_waitpid (pid
, &status
, 0);
1014 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1016 } while (ret
!= -1 || errno
!= ECHILD
);
1019 /* Return nonzero if the given thread is still alive. */
1021 linux_thread_alive (ptid_t ptid
)
1023 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1025 /* We assume we always know if a thread exits. If a whole process
1026 exited but we still haven't been able to report it to GDB, we'll
1027 hold on to the last lwp of the dead process. */
1034 /* Return 1 if this lwp has an interesting status pending. */
1036 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1038 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1039 ptid_t ptid
= * (ptid_t
*) arg
;
1040 struct thread_info
*thread
;
1042 /* Check if we're only interested in events from a specific process
1044 if (!ptid_equal (minus_one_ptid
, ptid
)
1045 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
1048 thread
= get_lwp_thread (lwp
);
1050 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1051 report any status pending the LWP may have. */
1052 if (thread
->last_resume_kind
== resume_stop
1053 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1056 return lwp
->status_pending_p
;
1060 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1062 ptid_t ptid
= *(ptid_t
*) data
;
1065 if (ptid_get_lwp (ptid
) != 0)
1066 lwp
= ptid_get_lwp (ptid
);
1068 lwp
= ptid_get_pid (ptid
);
1070 if (ptid_get_lwp (entry
->id
) == lwp
)
1077 find_lwp_pid (ptid_t ptid
)
1079 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
1082 static struct lwp_info
*
1083 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
1086 int to_wait_for
= -1;
1087 struct lwp_info
*child
= NULL
;
1090 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1092 if (ptid_equal (ptid
, minus_one_ptid
))
1093 to_wait_for
= -1; /* any child */
1095 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1101 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1102 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1105 perror_with_name ("waitpid");
1108 && (!WIFSTOPPED (*wstatp
)
1109 || (WSTOPSIG (*wstatp
) != 32
1110 && WSTOPSIG (*wstatp
) != 33)))
1111 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1113 child
= find_lwp_pid (pid_to_ptid (ret
));
1115 /* If we didn't find a process, one of two things presumably happened:
1116 - A process we started and then detached from has exited. Ignore it.
1117 - A process we are controlling has forked and the new child's stop
1118 was reported to us by the kernel. Save its PID. */
1119 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1121 add_pid_to_list (&stopped_pids
, ret
);
1124 else if (child
== NULL
)
1129 child
->last_status
= *wstatp
;
1131 /* Architecture-specific setup after inferior is running.
1132 This needs to happen after we have attached to the inferior
1133 and it is stopped for the first time, but before we access
1134 any inferior registers. */
1137 the_low_target
.arch_setup ();
1138 #ifdef HAVE_LINUX_REGSETS
1139 memset (disabled_regsets
, 0, num_regsets
);
1144 /* Fetch the possibly triggered data watchpoint info and store it in
1147 On some archs, like x86, that use debug registers to set
1148 watchpoints, it's possible that the way to know which watched
1149 address trapped, is to check the register that is used to select
1150 which address to watch. Problem is, between setting the
1151 watchpoint and reading back which data address trapped, the user
1152 may change the set of watchpoints, and, as a consequence, GDB
1153 changes the debug registers in the inferior. To avoid reading
1154 back a stale stopped-data-address when that happens, we cache in
1155 LP the fact that a watchpoint trapped, and the corresponding data
1156 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1157 changes the debug registers meanwhile, we have the cached data we
1160 if (WIFSTOPPED (*wstatp
) && WSTOPSIG (*wstatp
) == SIGTRAP
)
1162 if (the_low_target
.stopped_by_watchpoint
== NULL
)
1164 child
->stopped_by_watchpoint
= 0;
1168 struct thread_info
*saved_inferior
;
1170 saved_inferior
= current_inferior
;
1171 current_inferior
= get_lwp_thread (child
);
1173 child
->stopped_by_watchpoint
1174 = the_low_target
.stopped_by_watchpoint ();
1176 if (child
->stopped_by_watchpoint
)
1178 if (the_low_target
.stopped_data_address
!= NULL
)
1179 child
->stopped_data_address
1180 = the_low_target
.stopped_data_address ();
1182 child
->stopped_data_address
= 0;
1185 current_inferior
= saved_inferior
;
1189 /* Store the STOP_PC, with adjustment applied. This depends on the
1190 architecture being defined already (so that CHILD has a valid
1191 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1193 if (WIFSTOPPED (*wstatp
))
1194 child
->stop_pc
= get_stop_pc (child
);
1197 && WIFSTOPPED (*wstatp
)
1198 && the_low_target
.get_pc
!= NULL
)
1200 struct thread_info
*saved_inferior
= current_inferior
;
1201 struct regcache
*regcache
;
1204 current_inferior
= get_lwp_thread (child
);
1205 regcache
= get_thread_regcache (current_inferior
, 1);
1206 pc
= (*the_low_target
.get_pc
) (regcache
);
1207 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1208 current_inferior
= saved_inferior
;
1214 /* This function should only be called if the LWP got a SIGTRAP.
1216 Handle any tracepoint steps or hits. Return true if a tracepoint
1217 event was handled, 0 otherwise. */
1220 handle_tracepoints (struct lwp_info
*lwp
)
1222 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1223 int tpoint_related_event
= 0;
1225 /* If this tracepoint hit causes a tracing stop, we'll immediately
1226 uninsert tracepoints. To do this, we temporarily pause all
1227 threads, unpatch away, and then unpause threads. We need to make
1228 sure the unpausing doesn't resume LWP too. */
1231 /* And we need to be sure that any all-threads-stopping doesn't try
1232 to move threads out of the jump pads, as it could deadlock the
1233 inferior (LWP could be in the jump pad, maybe even holding the
1236 /* Do any necessary step collect actions. */
1237 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1239 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1241 /* See if we just hit a tracepoint and do its main collect
1243 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1247 gdb_assert (lwp
->suspended
== 0);
1248 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1250 if (tpoint_related_event
)
1253 fprintf (stderr
, "got a tracepoint event\n");
1260 /* Convenience wrapper. Returns true if LWP is presently collecting a
1264 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1265 struct fast_tpoint_collect_status
*status
)
1267 CORE_ADDR thread_area
;
1269 if (the_low_target
.get_thread_area
== NULL
)
1272 /* Get the thread area address. This is used to recognize which
1273 thread is which when tracing with the in-process agent library.
1274 We don't read anything from the address, and treat it as opaque;
1275 it's the address itself that we assume is unique per-thread. */
1276 if ((*the_low_target
.get_thread_area
) (lwpid_of (lwp
), &thread_area
) == -1)
1279 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1282 /* The reason we resume in the caller, is because we want to be able
1283 to pass lwp->status_pending as WSTAT, and we need to clear
1284 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1285 refuses to resume. */
1288 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1290 struct thread_info
*saved_inferior
;
1292 saved_inferior
= current_inferior
;
1293 current_inferior
= get_lwp_thread (lwp
);
1296 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1297 && supports_fast_tracepoints ()
1298 && in_process_agent_loaded ())
1300 struct fast_tpoint_collect_status status
;
1305 Checking whether LWP %ld needs to move out of the jump pad.\n",
1308 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1311 || (WSTOPSIG (*wstat
) != SIGILL
1312 && WSTOPSIG (*wstat
) != SIGFPE
1313 && WSTOPSIG (*wstat
) != SIGSEGV
1314 && WSTOPSIG (*wstat
) != SIGBUS
))
1316 lwp
->collecting_fast_tracepoint
= r
;
1320 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1322 /* Haven't executed the original instruction yet.
1323 Set breakpoint there, and wait till it's hit,
1324 then single-step until exiting the jump pad. */
1325 lwp
->exit_jump_pad_bkpt
1326 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1331 Checking whether LWP %ld needs to move out of the jump pad...it does\n",
1333 current_inferior
= saved_inferior
;
1340 /* If we get a synchronous signal while collecting, *and*
1341 while executing the (relocated) original instruction,
1342 reset the PC to point at the tpoint address, before
1343 reporting to GDB. Otherwise, it's an IPA lib bug: just
1344 report the signal to GDB, and pray for the best. */
1346 lwp
->collecting_fast_tracepoint
= 0;
1349 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1350 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1353 struct regcache
*regcache
;
1355 /* The si_addr on a few signals references the address
1356 of the faulting instruction. Adjust that as
1358 if ((WSTOPSIG (*wstat
) == SIGILL
1359 || WSTOPSIG (*wstat
) == SIGFPE
1360 || WSTOPSIG (*wstat
) == SIGBUS
1361 || WSTOPSIG (*wstat
) == SIGSEGV
)
1362 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &info
) == 0
1363 /* Final check just to make sure we don't clobber
1364 the siginfo of non-kernel-sent signals. */
1365 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1367 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1368 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &info
);
1371 regcache
= get_thread_regcache (get_lwp_thread (lwp
), 1);
1372 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1373 lwp
->stop_pc
= status
.tpoint_addr
;
1375 /* Cancel any fast tracepoint lock this thread was
1377 force_unlock_trace_buffer ();
1380 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1384 "Cancelling fast exit-jump-pad: removing bkpt. "
1385 "stopping all threads momentarily.\n");
1387 stop_all_lwps (1, lwp
);
1388 cancel_breakpoints ();
1390 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1391 lwp
->exit_jump_pad_bkpt
= NULL
;
1393 unstop_all_lwps (1, lwp
);
1395 gdb_assert (lwp
->suspended
>= 0);
1402 Checking whether LWP %ld needs to move out of the jump pad...no\n",
1405 current_inferior
= saved_inferior
;
1409 /* Enqueue one signal in the "signals to report later when out of the
1413 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1415 struct pending_signals
*p_sig
;
1419 Deferring signal %d for LWP %ld.\n", WSTOPSIG (*wstat
), lwpid_of (lwp
));
1423 struct pending_signals
*sig
;
1425 for (sig
= lwp
->pending_signals_to_report
;
1429 " Already queued %d\n",
1432 fprintf (stderr
, " (no more currently queued signals)\n");
1435 /* Don't enqueue non-RT signals if they are already in the deferred
1436 queue. (SIGSTOP being the easiest signal to see ending up here
1438 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1440 struct pending_signals
*sig
;
1442 for (sig
= lwp
->pending_signals_to_report
;
1446 if (sig
->signal
== WSTOPSIG (*wstat
))
1450 "Not requeuing already queued non-RT signal %d"
1459 p_sig
= xmalloc (sizeof (*p_sig
));
1460 p_sig
->prev
= lwp
->pending_signals_to_report
;
1461 p_sig
->signal
= WSTOPSIG (*wstat
);
1462 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1463 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
1465 lwp
->pending_signals_to_report
= p_sig
;
1468 /* Dequeue one signal from the "signals to report later when out of
1469 the jump pad" list. */
1472 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1474 if (lwp
->pending_signals_to_report
!= NULL
)
1476 struct pending_signals
**p_sig
;
1478 p_sig
= &lwp
->pending_signals_to_report
;
1479 while ((*p_sig
)->prev
!= NULL
)
1480 p_sig
= &(*p_sig
)->prev
;
1482 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1483 if ((*p_sig
)->info
.si_signo
!= 0)
1484 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
1489 fprintf (stderr
, "Reporting deferred signal %d for LWP %ld.\n",
1490 WSTOPSIG (*wstat
), lwpid_of (lwp
));
1494 struct pending_signals
*sig
;
1496 for (sig
= lwp
->pending_signals_to_report
;
1500 " Still queued %d\n",
1503 fprintf (stderr
, " (no more queued signals)\n");
1512 /* Arrange for a breakpoint to be hit again later. We don't keep the
1513 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1514 will handle the current event, eventually we will resume this LWP,
1515 and this breakpoint will trap again. */
1518 cancel_breakpoint (struct lwp_info
*lwp
)
1520 struct thread_info
*saved_inferior
;
1522 /* There's nothing to do if we don't support breakpoints. */
1523 if (!supports_breakpoints ())
1526 /* breakpoint_at reads from current inferior. */
1527 saved_inferior
= current_inferior
;
1528 current_inferior
= get_lwp_thread (lwp
);
1530 if ((*the_low_target
.breakpoint_at
) (lwp
->stop_pc
))
1534 "CB: Push back breakpoint for %s\n",
1535 target_pid_to_str (ptid_of (lwp
)));
1537 /* Back up the PC if necessary. */
1538 if (the_low_target
.decr_pc_after_break
)
1540 struct regcache
*regcache
1541 = get_thread_regcache (current_inferior
, 1);
1542 (*the_low_target
.set_pc
) (regcache
, lwp
->stop_pc
);
1545 current_inferior
= saved_inferior
;
1552 "CB: No breakpoint found at %s for [%s]\n",
1553 paddress (lwp
->stop_pc
),
1554 target_pid_to_str (ptid_of (lwp
)));
1557 current_inferior
= saved_inferior
;
1561 /* When the event-loop is doing a step-over, this points at the thread
1563 ptid_t step_over_bkpt
;
1565 /* Wait for an event from child PID. If PID is -1, wait for any
1566 child. Store the stop status through the status pointer WSTAT.
1567 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1568 event was found and OPTIONS contains WNOHANG. Return the PID of
1569 the stopped child otherwise. */
1572 linux_wait_for_event_1 (ptid_t ptid
, int *wstat
, int options
)
1574 struct lwp_info
*event_child
, *requested_child
;
1577 requested_child
= NULL
;
1579 /* Check for a lwp with a pending status. */
1581 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
1583 event_child
= (struct lwp_info
*)
1584 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1585 if (debug_threads
&& event_child
)
1586 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1590 requested_child
= find_lwp_pid (ptid
);
1592 if (!stopping_threads
1593 && requested_child
->status_pending_p
1594 && requested_child
->collecting_fast_tracepoint
)
1596 enqueue_one_deferred_signal (requested_child
,
1597 &requested_child
->status_pending
);
1598 requested_child
->status_pending_p
= 0;
1599 requested_child
->status_pending
= 0;
1600 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
1603 if (requested_child
->suspended
1604 && requested_child
->status_pending_p
)
1605 fatal ("requesting an event out of a suspended child?");
1607 if (requested_child
->status_pending_p
)
1608 event_child
= requested_child
;
1611 if (event_child
!= NULL
)
1614 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1615 lwpid_of (event_child
), event_child
->status_pending
);
1616 *wstat
= event_child
->status_pending
;
1617 event_child
->status_pending_p
= 0;
1618 event_child
->status_pending
= 0;
1619 current_inferior
= get_lwp_thread (event_child
);
1620 return lwpid_of (event_child
);
1623 /* We only enter this loop if no process has a pending wait status. Thus
1624 any action taken in response to a wait status inside this loop is
1625 responding as soon as we detect the status, not after any pending
1629 event_child
= linux_wait_for_lwp (ptid
, wstat
, options
);
1631 if ((options
& WNOHANG
) && event_child
== NULL
)
1634 fprintf (stderr
, "WNOHANG set, no event found\n");
1638 if (event_child
== NULL
)
1639 error ("event from unknown child");
1641 current_inferior
= get_lwp_thread (event_child
);
1643 /* Check for thread exit. */
1644 if (! WIFSTOPPED (*wstat
))
1647 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1649 /* If the last thread is exiting, just return. */
1650 if (last_thread_of_process_p (current_inferior
))
1653 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1654 lwpid_of (event_child
));
1655 return lwpid_of (event_child
);
1660 current_inferior
= (struct thread_info
*) all_threads
.head
;
1662 fprintf (stderr
, "Current inferior is now %ld\n",
1663 lwpid_of (get_thread_lwp (current_inferior
)));
1667 current_inferior
= NULL
;
1669 fprintf (stderr
, "Current inferior is now <NULL>\n");
1672 /* If we were waiting for this particular child to do something...
1673 well, it did something. */
1674 if (requested_child
!= NULL
)
1676 int lwpid
= lwpid_of (event_child
);
1678 /* Cancel the step-over operation --- the thread that
1679 started it is gone. */
1680 if (finish_step_over (event_child
))
1681 unstop_all_lwps (1, event_child
);
1682 delete_lwp (event_child
);
1686 delete_lwp (event_child
);
1688 /* Wait for a more interesting event. */
1692 if (event_child
->must_set_ptrace_flags
)
1694 linux_enable_event_reporting (lwpid_of (event_child
));
1695 event_child
->must_set_ptrace_flags
= 0;
1698 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1699 && *wstat
>> 16 != 0)
1701 handle_extended_wait (event_child
, *wstat
);
1705 if (WIFSTOPPED (*wstat
)
1706 && WSTOPSIG (*wstat
) == SIGSTOP
1707 && event_child
->stop_expected
)
1712 fprintf (stderr
, "Expected stop.\n");
1713 event_child
->stop_expected
= 0;
1715 should_stop
= (current_inferior
->last_resume_kind
== resume_stop
1716 || stopping_threads
);
1720 linux_resume_one_lwp (event_child
,
1721 event_child
->stepping
, 0, NULL
);
1726 return lwpid_of (event_child
);
1734 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1738 if (ptid_is_pid (ptid
))
1740 /* A request to wait for a specific tgid. This is not possible
1741 with waitpid, so instead, we wait for any child, and leave
1742 children we're not interested in right now with a pending
1743 status to report later. */
1744 wait_ptid
= minus_one_ptid
;
1753 event_pid
= linux_wait_for_event_1 (wait_ptid
, wstat
, options
);
1756 && ptid_is_pid (ptid
) && ptid_get_pid (ptid
) != event_pid
)
1758 struct lwp_info
*event_child
1759 = find_lwp_pid (pid_to_ptid (event_pid
));
1761 if (! WIFSTOPPED (*wstat
))
1762 mark_lwp_dead (event_child
, *wstat
);
1765 event_child
->status_pending_p
= 1;
1766 event_child
->status_pending
= *wstat
;
1775 /* Count the LWP's that have had events. */
1778 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
1780 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1781 struct thread_info
*thread
= get_lwp_thread (lp
);
1784 gdb_assert (count
!= NULL
);
1786 /* Count only resumed LWPs that have a SIGTRAP event pending that
1787 should be reported to GDB. */
1788 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1789 && thread
->last_resume_kind
!= resume_stop
1790 && lp
->status_pending_p
1791 && WIFSTOPPED (lp
->status_pending
)
1792 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1793 && !breakpoint_inserted_here (lp
->stop_pc
))
1799 /* Select the LWP (if any) that is currently being single-stepped. */
1802 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1804 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1805 struct thread_info
*thread
= get_lwp_thread (lp
);
1807 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1808 && thread
->last_resume_kind
== resume_step
1809 && lp
->status_pending_p
)
1815 /* Select the Nth LWP that has had a SIGTRAP event that should be
1819 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1821 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1822 struct thread_info
*thread
= get_lwp_thread (lp
);
1823 int *selector
= data
;
1825 gdb_assert (selector
!= NULL
);
1827 /* Select only resumed LWPs that have a SIGTRAP event pending. */
1828 if (thread
->last_resume_kind
!= resume_stop
1829 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1830 && lp
->status_pending_p
1831 && WIFSTOPPED (lp
->status_pending
)
1832 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1833 && !breakpoint_inserted_here (lp
->stop_pc
))
1834 if ((*selector
)-- == 0)
1841 cancel_breakpoints_callback (struct inferior_list_entry
*entry
, void *data
)
1843 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1844 struct thread_info
*thread
= get_lwp_thread (lp
);
1845 struct lwp_info
*event_lp
= data
;
1847 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
1851 /* If a LWP other than the LWP that we're reporting an event for has
1852 hit a GDB breakpoint (as opposed to some random trap signal),
1853 then just arrange for it to hit it again later. We don't keep
1854 the SIGTRAP status and don't forward the SIGTRAP signal to the
1855 LWP. We will handle the current event, eventually we will resume
1856 all LWPs, and this one will get its breakpoint trap again.
1858 If we do not do this, then we run the risk that the user will
1859 delete or disable the breakpoint, but the LWP will have already
1862 if (thread
->last_resume_kind
!= resume_stop
1863 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1864 && lp
->status_pending_p
1865 && WIFSTOPPED (lp
->status_pending
)
1866 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1868 && !lp
->stopped_by_watchpoint
1869 && cancel_breakpoint (lp
))
1870 /* Throw away the SIGTRAP. */
1871 lp
->status_pending_p
= 0;
1877 linux_cancel_breakpoints (void)
1879 find_inferior (&all_lwps
, cancel_breakpoints_callback
, NULL
);
1882 /* Select one LWP out of those that have events pending. */
1885 select_event_lwp (struct lwp_info
**orig_lp
)
1888 int random_selector
;
1889 struct lwp_info
*event_lp
;
1891 /* Give preference to any LWP that is being single-stepped. */
1893 = (struct lwp_info
*) find_inferior (&all_lwps
,
1894 select_singlestep_lwp_callback
, NULL
);
1895 if (event_lp
!= NULL
)
1899 "SEL: Select single-step %s\n",
1900 target_pid_to_str (ptid_of (event_lp
)));
1904 /* No single-stepping LWP. Select one at random, out of those
1905 which have had SIGTRAP events. */
1907 /* First see how many SIGTRAP events we have. */
1908 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
1910 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
1911 random_selector
= (int)
1912 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
1914 if (debug_threads
&& num_events
> 1)
1916 "SEL: Found %d SIGTRAP events, selecting #%d\n",
1917 num_events
, random_selector
);
1919 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
1920 select_event_lwp_callback
,
1924 if (event_lp
!= NULL
)
1926 /* Switch the event LWP. */
1927 *orig_lp
= event_lp
;
1931 /* Decrement the suspend count of an LWP. */
1934 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
1936 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1938 /* Ignore EXCEPT. */
1944 gdb_assert (lwp
->suspended
>= 0);
1948 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
1952 unsuspend_all_lwps (struct lwp_info
*except
)
1954 find_inferior (&all_lwps
, unsuspend_one_lwp
, except
);
1957 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
1958 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
1960 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
1961 static ptid_t
linux_wait_1 (ptid_t ptid
,
1962 struct target_waitstatus
*ourstatus
,
1963 int target_options
);
1965 /* Stabilize threads (move out of jump pads).
1967 If a thread is midway collecting a fast tracepoint, we need to
1968 finish the collection and move it out of the jump pad before
1969 reporting the signal.
1971 This avoids recursion while collecting (when a signal arrives
1972 midway, and the signal handler itself collects), which would trash
1973 the trace buffer. In case the user set a breakpoint in a signal
1974 handler, this avoids the backtrace showing the jump pad, etc..
1975 Most importantly, there are certain things we can't do safely if
1976 threads are stopped in a jump pad (or in its callee's). For
1979 - starting a new trace run. A thread still collecting the
1980 previous run, could trash the trace buffer when resumed. The trace
1981 buffer control structures would have been reset but the thread had
1982 no way to tell. The thread could even midway memcpy'ing to the
1983 buffer, which would mean that when resumed, it would clobber the
1984 trace buffer that had been set for a new run.
1986 - we can't rewrite/reuse the jump pads for new tracepoints
1987 safely. Say you do tstart while a thread is stopped midway while
1988 collecting. When the thread is later resumed, it finishes the
1989 collection, and returns to the jump pad, to execute the original
1990 instruction that was under the tracepoint jump at the time the
1991 older run had been started. If the jump pad had been rewritten
1992 since for something else in the new run, the thread would now
1993 execute the wrong / random instructions. */
1996 linux_stabilize_threads (void)
1998 struct thread_info
*save_inferior
;
1999 struct lwp_info
*lwp_stuck
;
2002 = (struct lwp_info
*) find_inferior (&all_lwps
,
2003 stuck_in_jump_pad_callback
, NULL
);
2004 if (lwp_stuck
!= NULL
)
2007 fprintf (stderr
, "can't stabilize, LWP %ld is stuck in jump pad\n",
2008 lwpid_of (lwp_stuck
));
2012 save_inferior
= current_inferior
;
2014 stabilizing_threads
= 1;
2017 for_each_inferior (&all_lwps
, move_out_of_jump_pad_callback
);
2019 /* Loop until all are stopped out of the jump pads. */
2020 while (find_inferior (&all_lwps
, lwp_running
, NULL
) != NULL
)
2022 struct target_waitstatus ourstatus
;
2023 struct lwp_info
*lwp
;
2026 /* Note that we go through the full wait even loop. While
2027 moving threads out of jump pad, we need to be able to step
2028 over internal breakpoints and such. */
2029 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2031 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2033 lwp
= get_thread_lwp (current_inferior
);
2038 if (ourstatus
.value
.sig
!= TARGET_SIGNAL_0
2039 || current_inferior
->last_resume_kind
== resume_stop
)
2041 wstat
= W_STOPCODE (target_signal_to_host (ourstatus
.value
.sig
));
2042 enqueue_one_deferred_signal (lwp
, &wstat
);
2047 find_inferior (&all_lwps
, unsuspend_one_lwp
, NULL
);
2049 stabilizing_threads
= 0;
2051 current_inferior
= save_inferior
;
2056 = (struct lwp_info
*) find_inferior (&all_lwps
,
2057 stuck_in_jump_pad_callback
, NULL
);
2058 if (lwp_stuck
!= NULL
)
2059 fprintf (stderr
, "couldn't stabilize, LWP %ld got stuck in jump pad\n",
2060 lwpid_of (lwp_stuck
));
2064 /* Wait for process, returns status. */
2067 linux_wait_1 (ptid_t ptid
,
2068 struct target_waitstatus
*ourstatus
, int target_options
)
2071 struct lwp_info
*event_child
;
2074 int step_over_finished
;
2075 int bp_explains_trap
;
2076 int maybe_internal_trap
;
2080 /* Translate generic target options into linux options. */
2082 if (target_options
& TARGET_WNOHANG
)
2086 bp_explains_trap
= 0;
2088 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2090 /* If we were only supposed to resume one thread, only wait for
2091 that thread - if it's still alive. If it died, however - which
2092 can happen if we're coming from the thread death case below -
2093 then we need to make sure we restart the other threads. We could
2094 pick a thread at random or restart all; restarting all is less
2097 && !ptid_equal (cont_thread
, null_ptid
)
2098 && !ptid_equal (cont_thread
, minus_one_ptid
))
2100 struct thread_info
*thread
;
2102 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
2105 /* No stepping, no signal - unless one is pending already, of course. */
2108 struct thread_resume resume_info
;
2109 resume_info
.thread
= minus_one_ptid
;
2110 resume_info
.kind
= resume_continue
;
2111 resume_info
.sig
= 0;
2112 linux_resume (&resume_info
, 1);
2118 if (ptid_equal (step_over_bkpt
, null_ptid
))
2119 pid
= linux_wait_for_event (ptid
, &w
, options
);
2123 fprintf (stderr
, "step_over_bkpt set [%s], doing a blocking wait\n",
2124 target_pid_to_str (step_over_bkpt
));
2125 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2128 if (pid
== 0) /* only if TARGET_WNOHANG */
2131 event_child
= get_thread_lwp (current_inferior
);
2133 /* If we are waiting for a particular child, and it exited,
2134 linux_wait_for_event will return its exit status. Similarly if
2135 the last child exited. If this is not the last child, however,
2136 do not report it as exited until there is a 'thread exited' response
2137 available in the remote protocol. Instead, just wait for another event.
2138 This should be safe, because if the thread crashed we will already
2139 have reported the termination signal to GDB; that should stop any
2140 in-progress stepping operations, etc.
2142 Report the exit status of the last thread to exit. This matches
2143 LinuxThreads' behavior. */
2145 if (last_thread_of_process_p (current_inferior
))
2147 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2151 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2152 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2156 "\nChild exited with retcode = %x \n",
2161 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2162 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
2166 "\nChild terminated with signal = %x \n",
2171 return ptid_of (event_child
);
2176 if (!WIFSTOPPED (w
))
2180 /* If this event was not handled before, and is not a SIGTRAP, we
2181 report it. SIGILL and SIGSEGV are also treated as traps in case
2182 a breakpoint is inserted at the current PC. If this target does
2183 not support internal breakpoints at all, we also report the
2184 SIGTRAP without further processing; it's of no concern to us. */
2186 = (supports_breakpoints ()
2187 && (WSTOPSIG (w
) == SIGTRAP
2188 || ((WSTOPSIG (w
) == SIGILL
2189 || WSTOPSIG (w
) == SIGSEGV
)
2190 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2192 if (maybe_internal_trap
)
2194 /* Handle anything that requires bookkeeping before deciding to
2195 report the event or continue waiting. */
2197 /* First check if we can explain the SIGTRAP with an internal
2198 breakpoint, or if we should possibly report the event to GDB.
2199 Do this before anything that may remove or insert a
2201 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2203 /* We have a SIGTRAP, possibly a step-over dance has just
2204 finished. If so, tweak the state machine accordingly,
2205 reinsert breakpoints and delete any reinsert (software
2206 single-step) breakpoints. */
2207 step_over_finished
= finish_step_over (event_child
);
2209 /* Now invoke the callbacks of any internal breakpoints there. */
2210 check_breakpoints (event_child
->stop_pc
);
2212 /* Handle tracepoint data collecting. This may overflow the
2213 trace buffer, and cause a tracing stop, removing
2215 trace_event
= handle_tracepoints (event_child
);
2217 if (bp_explains_trap
)
2219 /* If we stepped or ran into an internal breakpoint, we've
2220 already handled it. So next time we resume (from this
2221 PC), we should step over it. */
2223 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2225 if (breakpoint_here (event_child
->stop_pc
))
2226 event_child
->need_step_over
= 1;
2231 /* We have some other signal, possibly a step-over dance was in
2232 progress, and it should be cancelled too. */
2233 step_over_finished
= finish_step_over (event_child
);
2236 /* We have all the data we need. Either report the event to GDB, or
2237 resume threads and keep waiting for more. */
2239 /* If we're collecting a fast tracepoint, finish the collection and
2240 move out of the jump pad before delivering a signal. See
2241 linux_stabilize_threads. */
2244 && WSTOPSIG (w
) != SIGTRAP
2245 && supports_fast_tracepoints ()
2246 && in_process_agent_loaded ())
2250 "Got signal %d for LWP %ld. Check if we need "
2251 "to defer or adjust it.\n",
2252 WSTOPSIG (w
), lwpid_of (event_child
));
2254 /* Allow debugging the jump pad itself. */
2255 if (current_inferior
->last_resume_kind
!= resume_step
2256 && maybe_move_out_of_jump_pad (event_child
, &w
))
2258 enqueue_one_deferred_signal (event_child
, &w
);
2262 "Signal %d for LWP %ld deferred (in jump pad)\n",
2263 WSTOPSIG (w
), lwpid_of (event_child
));
2265 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2270 if (event_child
->collecting_fast_tracepoint
)
2274 LWP %ld was trying to move out of the jump pad (%d). \
2275 Check if we're already there.\n",
2276 lwpid_of (event_child
),
2277 event_child
->collecting_fast_tracepoint
);
2281 event_child
->collecting_fast_tracepoint
2282 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2284 if (event_child
->collecting_fast_tracepoint
!= 1)
2286 /* No longer need this breakpoint. */
2287 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2291 "No longer need exit-jump-pad bkpt; removing it."
2292 "stopping all threads momentarily.\n");
2294 /* Other running threads could hit this breakpoint.
2295 We don't handle moribund locations like GDB does,
2296 instead we always pause all threads when removing
2297 breakpoints, so that any step-over or
2298 decr_pc_after_break adjustment is always taken
2299 care of while the breakpoint is still
2301 stop_all_lwps (1, event_child
);
2302 cancel_breakpoints ();
2304 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2305 event_child
->exit_jump_pad_bkpt
= NULL
;
2307 unstop_all_lwps (1, event_child
);
2309 gdb_assert (event_child
->suspended
>= 0);
2313 if (event_child
->collecting_fast_tracepoint
== 0)
2317 "fast tracepoint finished "
2318 "collecting successfully.\n");
2320 /* We may have a deferred signal to report. */
2321 if (dequeue_one_deferred_signal (event_child
, &w
))
2324 fprintf (stderr
, "dequeued one signal.\n");
2329 fprintf (stderr
, "no deferred signals.\n");
2331 if (stabilizing_threads
)
2333 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2334 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2335 return ptid_of (event_child
);
2341 /* Check whether GDB would be interested in this event. */
2343 /* If GDB is not interested in this signal, don't stop other
2344 threads, and don't report it to GDB. Just resume the inferior
2345 right away. We do this for threading-related signals as well as
2346 any that GDB specifically requested we ignore. But never ignore
2347 SIGSTOP if we sent it ourselves, and do not ignore signals when
2348 stepping - they may require special handling to skip the signal
2350 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2353 && current_inferior
->last_resume_kind
!= resume_step
2355 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2356 (current_process ()->private->thread_db
!= NULL
2357 && (WSTOPSIG (w
) == __SIGRTMIN
2358 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2361 (pass_signals
[target_signal_from_host (WSTOPSIG (w
))]
2362 && !(WSTOPSIG (w
) == SIGSTOP
2363 && current_inferior
->last_resume_kind
== resume_stop
))))
2365 siginfo_t info
, *info_p
;
2368 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
2369 WSTOPSIG (w
), lwpid_of (event_child
));
2371 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
2375 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2376 WSTOPSIG (w
), info_p
);
2380 /* If GDB wanted this thread to single step, we always want to
2381 report the SIGTRAP, and let GDB handle it. Watchpoints should
2382 always be reported. So should signals we can't explain. A
2383 SIGTRAP we can't explain could be a GDB breakpoint --- we may or
2384 not support Z0 breakpoints. If we do, we're be able to handle
2385 GDB breakpoints on top of internal breakpoints, by handling the
2386 internal breakpoint and still reporting the event to GDB. If we
2387 don't, we're out of luck, GDB won't see the breakpoint hit. */
2388 report_to_gdb
= (!maybe_internal_trap
2389 || current_inferior
->last_resume_kind
== resume_step
2390 || event_child
->stopped_by_watchpoint
2391 || (!step_over_finished
2392 && !bp_explains_trap
&& !trace_event
)
2393 || gdb_breakpoint_here (event_child
->stop_pc
));
2395 /* We found no reason GDB would want us to stop. We either hit one
2396 of our own breakpoints, or finished an internal step GDB
2397 shouldn't know about. */
2402 if (bp_explains_trap
)
2403 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2404 if (step_over_finished
)
2405 fprintf (stderr
, "Step-over finished.\n");
2407 fprintf (stderr
, "Tracepoint event.\n");
2410 /* We're not reporting this breakpoint to GDB, so apply the
2411 decr_pc_after_break adjustment to the inferior's regcache
2414 if (the_low_target
.set_pc
!= NULL
)
2416 struct regcache
*regcache
2417 = get_thread_regcache (get_lwp_thread (event_child
), 1);
2418 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2421 /* We may have finished stepping over a breakpoint. If so,
2422 we've stopped and suspended all LWPs momentarily except the
2423 stepping one. This is where we resume them all again. We're
2424 going to keep waiting, so use proceed, which handles stepping
2425 over the next breakpoint. */
2427 fprintf (stderr
, "proceeding all threads.\n");
2429 if (step_over_finished
)
2430 unsuspend_all_lwps (event_child
);
2432 proceed_all_lwps ();
2438 if (current_inferior
->last_resume_kind
== resume_step
)
2439 fprintf (stderr
, "GDB wanted to single-step, reporting event.\n");
2440 if (event_child
->stopped_by_watchpoint
)
2441 fprintf (stderr
, "Stopped by watchpoint.\n");
2442 if (gdb_breakpoint_here (event_child
->stop_pc
))
2443 fprintf (stderr
, "Stopped by GDB breakpoint.\n");
2445 fprintf (stderr
, "Hit a non-gdbserver trap event.\n");
2448 /* Alright, we're going to report a stop. */
2450 if (!non_stop
&& !stabilizing_threads
)
2452 /* In all-stop, stop all threads. */
2453 stop_all_lwps (0, NULL
);
2455 /* If we're not waiting for a specific LWP, choose an event LWP
2456 from among those that have had events. Giving equal priority
2457 to all LWPs that have had events helps prevent
2459 if (ptid_equal (ptid
, minus_one_ptid
))
2461 event_child
->status_pending_p
= 1;
2462 event_child
->status_pending
= w
;
2464 select_event_lwp (&event_child
);
2466 event_child
->status_pending_p
= 0;
2467 w
= event_child
->status_pending
;
2470 /* Now that we've selected our final event LWP, cancel any
2471 breakpoints in other LWPs that have hit a GDB breakpoint.
2472 See the comment in cancel_breakpoints_callback to find out
2474 find_inferior (&all_lwps
, cancel_breakpoints_callback
, event_child
);
2476 /* Stabilize threads (move out of jump pads). */
2477 stabilize_threads ();
2481 /* If we just finished a step-over, then all threads had been
2482 momentarily paused. In all-stop, that's fine, we want
2483 threads stopped by now anyway. In non-stop, we need to
2484 re-resume threads that GDB wanted to be running. */
2485 if (step_over_finished
)
2486 unstop_all_lwps (1, event_child
);
2489 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2491 if (current_inferior
->last_resume_kind
== resume_stop
2492 && WSTOPSIG (w
) == SIGSTOP
)
2494 /* A thread that has been requested to stop by GDB with vCont;t,
2495 and it stopped cleanly, so report as SIG0. The use of
2496 SIGSTOP is an implementation detail. */
2497 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2499 else if (current_inferior
->last_resume_kind
== resume_stop
2500 && WSTOPSIG (w
) != SIGSTOP
)
2502 /* A thread that has been requested to stop by GDB with vCont;t,
2503 but, it stopped for other reasons. */
2504 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2508 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2511 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
2514 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
2515 target_pid_to_str (ptid_of (event_child
)),
2517 ourstatus
->value
.sig
);
2519 return ptid_of (event_child
);
2522 /* Get rid of any pending event in the pipe. */
2524 async_file_flush (void)
2530 ret
= read (linux_event_pipe
[0], &buf
, 1);
2531 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
2534 /* Put something in the pipe, so the event loop wakes up. */
2536 async_file_mark (void)
2540 async_file_flush ();
2543 ret
= write (linux_event_pipe
[1], "+", 1);
2544 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
2546 /* Ignore EAGAIN. If the pipe is full, the event loop will already
2547 be awakened anyway. */
2551 linux_wait (ptid_t ptid
,
2552 struct target_waitstatus
*ourstatus
, int target_options
)
2557 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
2559 /* Flush the async file first. */
2560 if (target_is_async_p ())
2561 async_file_flush ();
2563 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
2565 /* If at least one stop was reported, there may be more. A single
2566 SIGCHLD can signal more than one child stop. */
2567 if (target_is_async_p ()
2568 && (target_options
& TARGET_WNOHANG
) != 0
2569 && !ptid_equal (event_ptid
, null_ptid
))
2575 /* Send a signal to an LWP. */
2578 kill_lwp (unsigned long lwpid
, int signo
)
2580 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2581 fails, then we are not using nptl threads and we should be using kill. */
2585 static int tkill_failed
;
2592 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2593 if (errno
!= ENOSYS
)
2600 return kill (lwpid
, signo
);
2604 linux_stop_lwp (struct lwp_info
*lwp
)
2610 send_sigstop (struct lwp_info
*lwp
)
2614 pid
= lwpid_of (lwp
);
2616 /* If we already have a pending stop signal for this process, don't
2618 if (lwp
->stop_expected
)
2621 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
2627 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
2629 lwp
->stop_expected
= 1;
2630 kill_lwp (pid
, SIGSTOP
);
2634 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
2636 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2638 /* Ignore EXCEPT. */
2649 /* Increment the suspend count of an LWP, and stop it, if not stopped
2652 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
2655 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2657 /* Ignore EXCEPT. */
2663 return send_sigstop_callback (entry
, except
);
2667 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
2669 /* It's dead, really. */
2672 /* Store the exit status for later. */
2673 lwp
->status_pending_p
= 1;
2674 lwp
->status_pending
= wstat
;
2676 /* Prevent trying to stop it. */
2679 /* No further stops are expected from a dead lwp. */
2680 lwp
->stop_expected
= 0;
2684 wait_for_sigstop (struct inferior_list_entry
*entry
)
2686 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2687 struct thread_info
*saved_inferior
;
2696 fprintf (stderr
, "wait_for_sigstop: LWP %ld already stopped\n",
2701 saved_inferior
= current_inferior
;
2702 if (saved_inferior
!= NULL
)
2703 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
2705 saved_tid
= null_ptid
; /* avoid bogus unused warning */
2707 ptid
= lwp
->head
.id
;
2710 fprintf (stderr
, "wait_for_sigstop: pulling one event\n");
2712 pid
= linux_wait_for_event (ptid
, &wstat
, __WALL
);
2714 /* If we stopped with a non-SIGSTOP signal, save it for later
2715 and record the pending SIGSTOP. If the process exited, just
2717 if (WIFSTOPPED (wstat
))
2720 fprintf (stderr
, "LWP %ld stopped with signal %d\n",
2721 lwpid_of (lwp
), WSTOPSIG (wstat
));
2723 if (WSTOPSIG (wstat
) != SIGSTOP
)
2726 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
2727 lwpid_of (lwp
), wstat
);
2729 lwp
->status_pending_p
= 1;
2730 lwp
->status_pending
= wstat
;
2736 fprintf (stderr
, "Process %d exited while stopping LWPs\n", pid
);
2738 lwp
= find_lwp_pid (pid_to_ptid (pid
));
2741 /* Leave this status pending for the next time we're able to
2742 report it. In the mean time, we'll report this lwp as
2743 dead to GDB, so GDB doesn't try to read registers and
2744 memory from it. This can only happen if this was the
2745 last thread of the process; otherwise, PID is removed
2746 from the thread tables before linux_wait_for_event
2748 mark_lwp_dead (lwp
, wstat
);
2752 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
2753 current_inferior
= saved_inferior
;
2757 fprintf (stderr
, "Previously current thread died.\n");
2761 /* We can't change the current inferior behind GDB's back,
2762 otherwise, a subsequent command may apply to the wrong
2764 current_inferior
= NULL
;
2768 /* Set a valid thread as current. */
2769 set_desired_inferior (0);
2774 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
2775 move it out, because we need to report the stop event to GDB. For
2776 example, if the user puts a breakpoint in the jump pad, it's
2777 because she wants to debug it. */
2780 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
2782 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2783 struct thread_info
*thread
= get_lwp_thread (lwp
);
2785 gdb_assert (lwp
->suspended
== 0);
2786 gdb_assert (lwp
->stopped
);
2788 /* Allow debugging the jump pad, gdb_collect, etc.. */
2789 return (supports_fast_tracepoints ()
2790 && in_process_agent_loaded ()
2791 && (gdb_breakpoint_here (lwp
->stop_pc
)
2792 || lwp
->stopped_by_watchpoint
2793 || thread
->last_resume_kind
== resume_step
)
2794 && linux_fast_tracepoint_collecting (lwp
, NULL
));
2798 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
2800 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2801 struct thread_info
*thread
= get_lwp_thread (lwp
);
2804 gdb_assert (lwp
->suspended
== 0);
2805 gdb_assert (lwp
->stopped
);
2807 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
2809 /* Allow debugging the jump pad, gdb_collect, etc. */
2810 if (!gdb_breakpoint_here (lwp
->stop_pc
)
2811 && !lwp
->stopped_by_watchpoint
2812 && thread
->last_resume_kind
!= resume_step
2813 && maybe_move_out_of_jump_pad (lwp
, wstat
))
2817 "LWP %ld needs stabilizing (in jump pad)\n",
2822 lwp
->status_pending_p
= 0;
2823 enqueue_one_deferred_signal (lwp
, wstat
);
2827 "Signal %d for LWP %ld deferred "
2829 WSTOPSIG (*wstat
), lwpid_of (lwp
));
2832 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
2839 lwp_running (struct inferior_list_entry
*entry
, void *data
)
2841 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2850 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
2851 If SUSPEND, then also increase the suspend count of every LWP,
2855 stop_all_lwps (int suspend
, struct lwp_info
*except
)
2857 stopping_threads
= 1;
2860 find_inferior (&all_lwps
, suspend_and_send_sigstop_callback
, except
);
2862 find_inferior (&all_lwps
, send_sigstop_callback
, except
);
2863 for_each_inferior (&all_lwps
, wait_for_sigstop
);
2864 stopping_threads
= 0;
2867 /* Resume execution of the inferior process.
2868 If STEP is nonzero, single-step it.
2869 If SIGNAL is nonzero, give it that signal. */
2872 linux_resume_one_lwp (struct lwp_info
*lwp
,
2873 int step
, int signal
, siginfo_t
*info
)
2875 struct thread_info
*saved_inferior
;
2876 int fast_tp_collecting
;
2878 if (lwp
->stopped
== 0)
2881 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
2883 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
2885 /* Cancel actions that rely on GDB not changing the PC (e.g., the
2886 user used the "jump" command, or "set $pc = foo"). */
2887 if (lwp
->stop_pc
!= get_pc (lwp
))
2889 /* Collecting 'while-stepping' actions doesn't make sense
2891 release_while_stepping_state_list (get_lwp_thread (lwp
));
2894 /* If we have pending signals or status, and a new signal, enqueue the
2895 signal. Also enqueue the signal if we are waiting to reinsert a
2896 breakpoint; it will be picked up again below. */
2898 && (lwp
->status_pending_p
2899 || lwp
->pending_signals
!= NULL
2900 || lwp
->bp_reinsert
!= 0
2901 || fast_tp_collecting
))
2903 struct pending_signals
*p_sig
;
2904 p_sig
= xmalloc (sizeof (*p_sig
));
2905 p_sig
->prev
= lwp
->pending_signals
;
2906 p_sig
->signal
= signal
;
2908 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
2910 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
2911 lwp
->pending_signals
= p_sig
;
2914 if (lwp
->status_pending_p
)
2917 fprintf (stderr
, "Not resuming lwp %ld (%s, signal %d, stop %s);"
2918 " has pending status\n",
2919 lwpid_of (lwp
), step
? "step" : "continue", signal
,
2920 lwp
->stop_expected
? "expected" : "not expected");
2924 saved_inferior
= current_inferior
;
2925 current_inferior
= get_lwp_thread (lwp
);
2928 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
2929 lwpid_of (lwp
), step
? "step" : "continue", signal
,
2930 lwp
->stop_expected
? "expected" : "not expected");
2932 /* This bit needs some thinking about. If we get a signal that
2933 we must report while a single-step reinsert is still pending,
2934 we often end up resuming the thread. It might be better to
2935 (ew) allow a stack of pending events; then we could be sure that
2936 the reinsert happened right away and not lose any signals.
2938 Making this stack would also shrink the window in which breakpoints are
2939 uninserted (see comment in linux_wait_for_lwp) but not enough for
2940 complete correctness, so it won't solve that problem. It may be
2941 worthwhile just to solve this one, however. */
2942 if (lwp
->bp_reinsert
!= 0)
2945 fprintf (stderr
, " pending reinsert at 0x%s\n",
2946 paddress (lwp
->bp_reinsert
));
2948 if (lwp
->bp_reinsert
!= 0 && can_hardware_single_step ())
2950 if (fast_tp_collecting
== 0)
2953 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
2955 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
2962 /* Postpone any pending signal. It was enqueued above. */
2966 if (fast_tp_collecting
== 1)
2970 lwp %ld wants to get out of fast tracepoint jump pad (exit-jump-pad-bkpt)\n",
2973 /* Postpone any pending signal. It was enqueued above. */
2976 else if (fast_tp_collecting
== 2)
2980 lwp %ld wants to get out of fast tracepoint jump pad single-stepping\n",
2983 if (can_hardware_single_step ())
2986 fatal ("moving out of jump pad single-stepping"
2987 " not implemented on this target");
2989 /* Postpone any pending signal. It was enqueued above. */
2993 /* If we have while-stepping actions in this thread set it stepping.
2994 If we have a signal to deliver, it may or may not be set to
2995 SIG_IGN, we don't know. Assume so, and allow collecting
2996 while-stepping into a signal handler. A possible smart thing to
2997 do would be to set an internal breakpoint at the signal return
2998 address, continue, and carry on catching this while-stepping
2999 action only when that breakpoint is hit. A future
3001 if (get_lwp_thread (lwp
)->while_stepping
!= NULL
3002 && can_hardware_single_step ())
3006 "lwp %ld has a while-stepping action -> forcing step.\n",
3011 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
3013 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
3014 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
3015 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
3018 /* If we have pending signals, consume one unless we are trying to
3019 reinsert a breakpoint or we're trying to finish a fast tracepoint
3021 if (lwp
->pending_signals
!= NULL
3022 && lwp
->bp_reinsert
== 0
3023 && fast_tp_collecting
== 0)
3025 struct pending_signals
**p_sig
;
3027 p_sig
= &lwp
->pending_signals
;
3028 while ((*p_sig
)->prev
!= NULL
)
3029 p_sig
= &(*p_sig
)->prev
;
3031 signal
= (*p_sig
)->signal
;
3032 if ((*p_sig
)->info
.si_signo
!= 0)
3033 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
3039 if (the_low_target
.prepare_to_resume
!= NULL
)
3040 the_low_target
.prepare_to_resume (lwp
);
3042 regcache_invalidate_one ((struct inferior_list_entry
*)
3043 get_lwp_thread (lwp
));
3046 lwp
->stopped_by_watchpoint
= 0;
3047 lwp
->stepping
= step
;
3048 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0,
3049 /* Coerce to a uintptr_t first to avoid potential gcc warning
3050 of coercing an 8 byte integer to a 4 byte pointer. */
3051 (PTRACE_ARG4_TYPE
) (uintptr_t) signal
);
3053 current_inferior
= saved_inferior
;
3056 /* ESRCH from ptrace either means that the thread was already
3057 running (an error) or that it is gone (a race condition). If
3058 it's gone, we will get a notification the next time we wait,
3059 so we can ignore the error. We could differentiate these
3060 two, but it's tricky without waiting; the thread still exists
3061 as a zombie, so sending it signal 0 would succeed. So just
3066 perror_with_name ("ptrace");
3070 struct thread_resume_array
3072 struct thread_resume
*resume
;
3076 /* This function is called once per thread. We look up the thread
3077 in RESUME_PTR, and mark the thread with a pointer to the appropriate
3080 This algorithm is O(threads * resume elements), but resume elements
3081 is small (and will remain small at least until GDB supports thread
3084 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3086 struct lwp_info
*lwp
;
3087 struct thread_info
*thread
;
3089 struct thread_resume_array
*r
;
3091 thread
= (struct thread_info
*) entry
;
3092 lwp
= get_thread_lwp (thread
);
3095 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3097 ptid_t ptid
= r
->resume
[ndx
].thread
;
3098 if (ptid_equal (ptid
, minus_one_ptid
)
3099 || ptid_equal (ptid
, entry
->id
)
3100 || (ptid_is_pid (ptid
)
3101 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
3102 || (ptid_get_lwp (ptid
) == -1
3103 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
3105 if (r
->resume
[ndx
].kind
== resume_stop
3106 && thread
->last_resume_kind
== resume_stop
)
3109 fprintf (stderr
, "already %s LWP %ld at GDB's request\n",
3110 thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
3118 lwp
->resume
= &r
->resume
[ndx
];
3119 thread
->last_resume_kind
= lwp
->resume
->kind
;
3121 /* If we had a deferred signal to report, dequeue one now.
3122 This can happen if LWP gets more than one signal while
3123 trying to get out of a jump pad. */
3125 && !lwp
->status_pending_p
3126 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3128 lwp
->status_pending_p
= 1;
3132 "Dequeueing deferred signal %d for LWP %ld, "
3133 "leaving status pending.\n",
3134 WSTOPSIG (lwp
->status_pending
), lwpid_of (lwp
));
3141 /* No resume action for this thread. */
3148 /* Set *FLAG_P if this lwp has an interesting status pending. */
3150 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3152 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3154 /* LWPs which will not be resumed are not interesting, because
3155 we might not wait for them next time through linux_wait. */
3156 if (lwp
->resume
== NULL
)
3159 if (lwp
->status_pending_p
)
3160 * (int *) flag_p
= 1;
3165 /* Return 1 if this lwp that GDB wants running is stopped at an
3166 internal breakpoint that we need to step over. It assumes that any
3167 required STOP_PC adjustment has already been propagated to the
3168 inferior's regcache. */
3171 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3173 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3174 struct thread_info
*thread
;
3175 struct thread_info
*saved_inferior
;
3178 /* LWPs which will not be resumed are not interesting, because we
3179 might not wait for them next time through linux_wait. */
3185 "Need step over [LWP %ld]? Ignoring, not stopped\n",
3190 thread
= get_lwp_thread (lwp
);
3192 if (thread
->last_resume_kind
== resume_stop
)
3196 "Need step over [LWP %ld]? Ignoring, should remain stopped\n",
3201 gdb_assert (lwp
->suspended
>= 0);
3207 "Need step over [LWP %ld]? Ignoring, suspended\n",
3212 if (!lwp
->need_step_over
)
3216 "Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
3219 if (lwp
->status_pending_p
)
3223 "Need step over [LWP %ld]? Ignoring, has pending status.\n",
3228 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3232 /* If the PC has changed since we stopped, then don't do anything,
3233 and let the breakpoint/tracepoint be hit. This happens if, for
3234 instance, GDB handled the decr_pc_after_break subtraction itself,
3235 GDB is OOL stepping this thread, or the user has issued a "jump"
3236 command, or poked thread's registers herself. */
3237 if (pc
!= lwp
->stop_pc
)
3241 "Need step over [LWP %ld]? Cancelling, PC was changed. "
3242 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3243 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
3245 lwp
->need_step_over
= 0;
3249 saved_inferior
= current_inferior
;
3250 current_inferior
= thread
;
3252 /* We can only step over breakpoints we know about. */
3253 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3255 /* Don't step over a breakpoint that GDB expects to hit
3257 if (gdb_breakpoint_here (pc
))
3261 "Need step over [LWP %ld]? yes, but found"
3262 " GDB breakpoint at 0x%s; skipping step over\n",
3263 lwpid_of (lwp
), paddress (pc
));
3265 current_inferior
= saved_inferior
;
3272 "Need step over [LWP %ld]? yes, "
3273 "found breakpoint at 0x%s\n",
3274 lwpid_of (lwp
), paddress (pc
));
3276 /* We've found an lwp that needs stepping over --- return 1 so
3277 that find_inferior stops looking. */
3278 current_inferior
= saved_inferior
;
3280 /* If the step over is cancelled, this is set again. */
3281 lwp
->need_step_over
= 0;
3286 current_inferior
= saved_inferior
;
3290 "Need step over [LWP %ld]? No, no breakpoint found at 0x%s\n",
3291 lwpid_of (lwp
), paddress (pc
));
3296 /* Start a step-over operation on LWP. When LWP stopped at a
3297 breakpoint, to make progress, we need to remove the breakpoint out
3298 of the way. If we let other threads run while we do that, they may
3299 pass by the breakpoint location and miss hitting it. To avoid
3300 that, a step-over momentarily stops all threads while LWP is
3301 single-stepped while the breakpoint is temporarily uninserted from
3302 the inferior. When the single-step finishes, we reinsert the
3303 breakpoint, and let all threads that are supposed to be running,
3306 On targets that don't support hardware single-step, we don't
3307 currently support full software single-stepping. Instead, we only
3308 support stepping over the thread event breakpoint, by asking the
3309 low target where to place a reinsert breakpoint. Since this
3310 routine assumes the breakpoint being stepped over is a thread event
3311 breakpoint, it usually assumes the return address of the current
3312 function is a good enough place to set the reinsert breakpoint. */
3315 start_step_over (struct lwp_info
*lwp
)
3317 struct thread_info
*saved_inferior
;
3323 "Starting step-over on LWP %ld. Stopping all threads\n",
3326 stop_all_lwps (1, lwp
);
3327 gdb_assert (lwp
->suspended
== 0);
3330 fprintf (stderr
, "Done stopping all threads for step-over.\n");
3332 /* Note, we should always reach here with an already adjusted PC,
3333 either by GDB (if we're resuming due to GDB's request), or by our
3334 caller, if we just finished handling an internal breakpoint GDB
3335 shouldn't care about. */
3338 saved_inferior
= current_inferior
;
3339 current_inferior
= get_lwp_thread (lwp
);
3341 lwp
->bp_reinsert
= pc
;
3342 uninsert_breakpoints_at (pc
);
3343 uninsert_fast_tracepoint_jumps_at (pc
);
3345 if (can_hardware_single_step ())
3351 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3352 set_reinsert_breakpoint (raddr
);
3356 current_inferior
= saved_inferior
;
3358 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3360 /* Require next event from this LWP. */
3361 step_over_bkpt
= lwp
->head
.id
;
3365 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3366 start_step_over, if still there, and delete any reinsert
3367 breakpoints we've set, on non hardware single-step targets. */
3370 finish_step_over (struct lwp_info
*lwp
)
3372 if (lwp
->bp_reinsert
!= 0)
3375 fprintf (stderr
, "Finished step over.\n");
3377 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3378 may be no breakpoint to reinsert there by now. */
3379 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3380 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3382 lwp
->bp_reinsert
= 0;
3384 /* Delete any software-single-step reinsert breakpoints. No
3385 longer needed. We don't have to worry about other threads
3386 hitting this trap, and later not being able to explain it,
3387 because we were stepping over a breakpoint, and we hold all
3388 threads but LWP stopped while doing that. */
3389 if (!can_hardware_single_step ())
3390 delete_reinsert_breakpoints ();
3392 step_over_bkpt
= null_ptid
;
3399 /* This function is called once per thread. We check the thread's resume
3400 request, which will tell us whether to resume, step, or leave the thread
3401 stopped; and what signal, if any, it should be sent.
3403 For threads which we aren't explicitly told otherwise, we preserve
3404 the stepping flag; this is used for stepping over gdbserver-placed
3407 If pending_flags was set in any thread, we queue any needed
3408 signals, since we won't actually resume. We already have a pending
3409 event to report, so we don't need to preserve any step requests;
3410 they should be re-issued if necessary. */
3413 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3415 struct lwp_info
*lwp
;
3416 struct thread_info
*thread
;
3418 int leave_all_stopped
= * (int *) arg
;
3421 thread
= (struct thread_info
*) entry
;
3422 lwp
= get_thread_lwp (thread
);
3424 if (lwp
->resume
== NULL
)
3427 if (lwp
->resume
->kind
== resume_stop
)
3430 fprintf (stderr
, "resume_stop request for LWP %ld\n", lwpid_of (lwp
));
3435 fprintf (stderr
, "stopping LWP %ld\n", lwpid_of (lwp
));
3437 /* Stop the thread, and wait for the event asynchronously,
3438 through the event loop. */
3444 fprintf (stderr
, "already stopped LWP %ld\n",
3447 /* The LWP may have been stopped in an internal event that
3448 was not meant to be notified back to GDB (e.g., gdbserver
3449 breakpoint), so we should be reporting a stop event in
3452 /* If the thread already has a pending SIGSTOP, this is a
3453 no-op. Otherwise, something later will presumably resume
3454 the thread and this will cause it to cancel any pending
3455 operation, due to last_resume_kind == resume_stop. If
3456 the thread already has a pending status to report, we
3457 will still report it the next time we wait - see
3458 status_pending_p_callback. */
3460 /* If we already have a pending signal to report, then
3461 there's no need to queue a SIGSTOP, as this means we're
3462 midway through moving the LWP out of the jumppad, and we
3463 will report the pending signal as soon as that is
3465 if (lwp
->pending_signals_to_report
== NULL
)
3469 /* For stop requests, we're done. */
3471 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3475 /* If this thread which is about to be resumed has a pending status,
3476 then don't resume any threads - we can just report the pending
3477 status. Make sure to queue any signals that would otherwise be
3478 sent. In all-stop mode, we do this decision based on if *any*
3479 thread has a pending status. If there's a thread that needs the
3480 step-over-breakpoint dance, then don't resume any other thread
3481 but that particular one. */
3482 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
3487 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
3489 step
= (lwp
->resume
->kind
== resume_step
);
3490 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
3495 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
3497 /* If we have a new signal, enqueue the signal. */
3498 if (lwp
->resume
->sig
!= 0)
3500 struct pending_signals
*p_sig
;
3501 p_sig
= xmalloc (sizeof (*p_sig
));
3502 p_sig
->prev
= lwp
->pending_signals
;
3503 p_sig
->signal
= lwp
->resume
->sig
;
3504 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3506 /* If this is the same signal we were previously stopped by,
3507 make sure to queue its siginfo. We can ignore the return
3508 value of ptrace; if it fails, we'll skip
3509 PTRACE_SETSIGINFO. */
3510 if (WIFSTOPPED (lwp
->last_status
)
3511 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
3512 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
3514 lwp
->pending_signals
= p_sig
;
3518 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3524 linux_resume (struct thread_resume
*resume_info
, size_t n
)
3526 struct thread_resume_array array
= { resume_info
, n
};
3527 struct lwp_info
*need_step_over
= NULL
;
3529 int leave_all_stopped
;
3531 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
3533 /* If there is a thread which would otherwise be resumed, which has
3534 a pending status, then don't resume any threads - we can just
3535 report the pending status. Make sure to queue any signals that
3536 would otherwise be sent. In non-stop mode, we'll apply this
3537 logic to each thread individually. We consume all pending events
3538 before considering to start a step-over (in all-stop). */
3541 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
3543 /* If there is a thread which would otherwise be resumed, which is
3544 stopped at a breakpoint that needs stepping over, then don't
3545 resume any threads - have it step over the breakpoint with all
3546 other threads stopped, then resume all threads again. Make sure
3547 to queue any signals that would otherwise be delivered or
3549 if (!any_pending
&& supports_breakpoints ())
3551 = (struct lwp_info
*) find_inferior (&all_lwps
,
3552 need_step_over_p
, NULL
);
3554 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
3558 if (need_step_over
!= NULL
)
3559 fprintf (stderr
, "Not resuming all, need step over\n");
3560 else if (any_pending
)
3562 "Not resuming, all-stop and found "
3563 "an LWP with pending status\n");
3565 fprintf (stderr
, "Resuming, no pending status or step over needed\n");
3568 /* Even if we're leaving threads stopped, queue all signals we'd
3569 otherwise deliver. */
3570 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
3573 start_step_over (need_step_over
);
3576 /* This function is called once per thread. We check the thread's
3577 last resume request, which will tell us whether to resume, step, or
3578 leave the thread stopped. Any signal the client requested to be
3579 delivered has already been enqueued at this point.
3581 If any thread that GDB wants running is stopped at an internal
3582 breakpoint that needs stepping over, we start a step-over operation
3583 on that particular thread, and leave all others stopped. */
3586 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3588 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3589 struct thread_info
*thread
;
3597 "proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
3602 fprintf (stderr
, " LWP %ld already running\n", lwpid_of (lwp
));
3606 thread
= get_lwp_thread (lwp
);
3608 if (thread
->last_resume_kind
== resume_stop
3609 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
3612 fprintf (stderr
, " client wants LWP to remain %ld stopped\n",
3617 if (lwp
->status_pending_p
)
3620 fprintf (stderr
, " LWP %ld has pending status, leaving stopped\n",
3625 gdb_assert (lwp
->suspended
>= 0);
3630 fprintf (stderr
, " LWP %ld is suspended\n", lwpid_of (lwp
));
3634 if (thread
->last_resume_kind
== resume_stop
3635 && lwp
->pending_signals_to_report
== NULL
3636 && lwp
->collecting_fast_tracepoint
== 0)
3638 /* We haven't reported this LWP as stopped yet (otherwise, the
3639 last_status.kind check above would catch it, and we wouldn't
3640 reach here. This LWP may have been momentarily paused by a
3641 stop_all_lwps call while handling for example, another LWP's
3642 step-over. In that case, the pending expected SIGSTOP signal
3643 that was queued at vCont;t handling time will have already
3644 been consumed by wait_for_sigstop, and so we need to requeue
3645 another one here. Note that if the LWP already has a SIGSTOP
3646 pending, this is a no-op. */
3650 "Client wants LWP %ld to stop. "
3651 "Making sure it has a SIGSTOP pending\n",
3657 step
= thread
->last_resume_kind
== resume_step
;
3658 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3663 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3665 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3671 gdb_assert (lwp
->suspended
>= 0);
3673 return proceed_one_lwp (entry
, except
);
3676 /* When we finish a step-over, set threads running again. If there's
3677 another thread that may need a step-over, now's the time to start
3678 it. Eventually, we'll move all threads past their breakpoints. */
3681 proceed_all_lwps (void)
3683 struct lwp_info
*need_step_over
;
3685 /* If there is a thread which would otherwise be resumed, which is
3686 stopped at a breakpoint that needs stepping over, then don't
3687 resume any threads - have it step over the breakpoint with all
3688 other threads stopped, then resume all threads again. */
3690 if (supports_breakpoints ())
3693 = (struct lwp_info
*) find_inferior (&all_lwps
,
3694 need_step_over_p
, NULL
);
3696 if (need_step_over
!= NULL
)
3699 fprintf (stderr
, "proceed_all_lwps: found "
3700 "thread %ld needing a step-over\n",
3701 lwpid_of (need_step_over
));
3703 start_step_over (need_step_over
);
3709 fprintf (stderr
, "Proceeding, no step-over needed\n");
3711 find_inferior (&all_lwps
, proceed_one_lwp
, NULL
);
3714 /* Stopped LWPs that the client wanted to be running, that don't have
3715 pending statuses, are set to run again, except for EXCEPT, if not
3716 NULL. This undoes a stop_all_lwps call. */
3719 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
3725 "unstopping all lwps, except=(LWP %ld)\n", lwpid_of (except
));
3728 "unstopping all lwps\n");
3732 find_inferior (&all_lwps
, unsuspend_and_proceed_one_lwp
, except
);
3734 find_inferior (&all_lwps
, proceed_one_lwp
, except
);
3737 #ifdef HAVE_LINUX_USRREGS
3740 register_addr (int regnum
)
3744 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
3745 error ("Invalid register number %d.", regnum
);
3747 addr
= the_low_target
.regmap
[regnum
];
3752 /* Fetch one register. */
3754 fetch_register (struct regcache
*regcache
, int regno
)
3761 if (regno
>= the_low_target
.num_regs
)
3763 if ((*the_low_target
.cannot_fetch_register
) (regno
))
3766 regaddr
= register_addr (regno
);
3770 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
3771 & -sizeof (PTRACE_XFER_TYPE
));
3772 buf
= alloca (size
);
3774 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3775 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
3778 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
3779 ptrace (PTRACE_PEEKUSER
, pid
,
3780 /* Coerce to a uintptr_t first to avoid potential gcc warning
3781 of coercing an 8 byte integer to a 4 byte pointer. */
3782 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
, 0);
3783 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
3785 error ("reading register %d: %s", regno
, strerror (errno
));
3788 if (the_low_target
.supply_ptrace_register
)
3789 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
3791 supply_register (regcache
, regno
, buf
);
3794 /* Store one register. */
3796 store_register (struct regcache
*regcache
, int regno
)
3803 if (regno
>= the_low_target
.num_regs
)
3805 if ((*the_low_target
.cannot_store_register
) (regno
))
3808 regaddr
= register_addr (regno
);
3812 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
3813 & -sizeof (PTRACE_XFER_TYPE
));
3814 buf
= alloca (size
);
3815 memset (buf
, 0, size
);
3817 if (the_low_target
.collect_ptrace_register
)
3818 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
3820 collect_register (regcache
, regno
, buf
);
3822 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3823 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
3826 ptrace (PTRACE_POKEUSER
, pid
,
3827 /* Coerce to a uintptr_t first to avoid potential gcc warning
3828 about coercing an 8 byte integer to a 4 byte pointer. */
3829 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
,
3830 (PTRACE_ARG4_TYPE
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
3833 /* At this point, ESRCH should mean the process is
3834 already gone, in which case we simply ignore attempts
3835 to change its registers. See also the related
3836 comment in linux_resume_one_lwp. */
3840 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
3841 error ("writing register %d: %s", regno
, strerror (errno
));
3843 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
3847 /* Fetch all registers, or just one, from the child process. */
3849 usr_fetch_inferior_registers (struct regcache
*regcache
, int regno
)
3852 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
3853 fetch_register (regcache
, regno
);
3855 fetch_register (regcache
, regno
);
3858 /* Store our register values back into the inferior.
3859 If REGNO is -1, do this for all registers.
3860 Otherwise, REGNO specifies which register (so we can save time). */
3862 usr_store_inferior_registers (struct regcache
*regcache
, int regno
)
3865 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
3866 store_register (regcache
, regno
);
3868 store_register (regcache
, regno
);
3870 #endif /* HAVE_LINUX_USRREGS */
3874 #ifdef HAVE_LINUX_REGSETS
3877 regsets_fetch_inferior_registers (struct regcache
*regcache
)
3879 struct regset_info
*regset
;
3880 int saw_general_regs
= 0;
3884 regset
= target_regsets
;
3886 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3887 while (regset
->size
>= 0)
3892 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
3898 buf
= xmalloc (regset
->size
);
3900 nt_type
= regset
->nt_type
;
3904 iov
.iov_len
= regset
->size
;
3905 data
= (void *) &iov
;
3911 res
= ptrace (regset
->get_request
, pid
, nt_type
, data
);
3913 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
3919 /* If we get EIO on a regset, do not try it again for
3921 disabled_regsets
[regset
- target_regsets
] = 1;
3928 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
3933 else if (regset
->type
== GENERAL_REGS
)
3934 saw_general_regs
= 1;
3935 regset
->store_function (regcache
, buf
);
3939 if (saw_general_regs
)
3946 regsets_store_inferior_registers (struct regcache
*regcache
)
3948 struct regset_info
*regset
;
3949 int saw_general_regs
= 0;
3953 regset
= target_regsets
;
3955 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3956 while (regset
->size
>= 0)
3961 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
3967 buf
= xmalloc (regset
->size
);
3969 /* First fill the buffer with the current register set contents,
3970 in case there are any items in the kernel's regset that are
3971 not in gdbserver's regcache. */
3973 nt_type
= regset
->nt_type
;
3977 iov
.iov_len
= regset
->size
;
3978 data
= (void *) &iov
;
3984 res
= ptrace (regset
->get_request
, pid
, nt_type
, data
);
3986 res
= ptrace (regset
->get_request
, pid
, &iov
, data
);
3991 /* Then overlay our cached registers on that. */
3992 regset
->fill_function (regcache
, buf
);
3994 /* Only now do we write the register set. */
3996 res
= ptrace (regset
->set_request
, pid
, nt_type
, data
);
3998 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4006 /* If we get EIO on a regset, do not try it again for
4008 disabled_regsets
[regset
- target_regsets
] = 1;
4012 else if (errno
== ESRCH
)
4014 /* At this point, ESRCH should mean the process is
4015 already gone, in which case we simply ignore attempts
4016 to change its registers. See also the related
4017 comment in linux_resume_one_lwp. */
4023 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4026 else if (regset
->type
== GENERAL_REGS
)
4027 saw_general_regs
= 1;
4031 if (saw_general_regs
)
4038 #endif /* HAVE_LINUX_REGSETS */
4042 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4044 #ifdef HAVE_LINUX_REGSETS
4045 if (regsets_fetch_inferior_registers (regcache
) == 0)
4048 #ifdef HAVE_LINUX_USRREGS
4049 usr_fetch_inferior_registers (regcache
, regno
);
4054 linux_store_registers (struct regcache
*regcache
, int regno
)
4056 #ifdef HAVE_LINUX_REGSETS
4057 if (regsets_store_inferior_registers (regcache
) == 0)
4060 #ifdef HAVE_LINUX_USRREGS
4061 usr_store_inferior_registers (regcache
, regno
);
4066 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4067 to debugger memory starting at MYADDR. */
4070 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4073 /* Round starting address down to longword boundary. */
4074 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4075 /* Round ending address up; get number of longwords that makes. */
4077 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4078 / sizeof (PTRACE_XFER_TYPE
);
4079 /* Allocate buffer of that many longwords. */
4080 register PTRACE_XFER_TYPE
*buffer
4081 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4084 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4086 /* Try using /proc. Don't bother for one word. */
4087 if (len
>= 3 * sizeof (long))
4089 /* We could keep this file open and cache it - possibly one per
4090 thread. That requires some juggling, but is even faster. */
4091 sprintf (filename
, "/proc/%d/mem", pid
);
4092 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4096 /* If pread64 is available, use it. It's faster if the kernel
4097 supports it (only one syscall), and it's 64-bit safe even on
4098 32-bit platforms (for instance, SPARC debugging a SPARC64
4101 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
4103 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, myaddr
, len
) != len
)
4115 /* Read all the longwords */
4116 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4119 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4120 about coercing an 8 byte integer to a 4 byte pointer. */
4121 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4122 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4127 /* Copy appropriate bytes out of the buffer. */
4129 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4135 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4136 memory at MEMADDR. On failure (cannot write to the inferior)
4137 returns the value of errno. */
4140 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4143 /* Round starting address down to longword boundary. */
4144 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4145 /* Round ending address up; get number of longwords that makes. */
4147 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4148 / sizeof (PTRACE_XFER_TYPE
);
4150 /* Allocate buffer of that many longwords. */
4151 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4152 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4154 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4158 /* Dump up to four bytes. */
4159 unsigned int val
= * (unsigned int *) myaddr
;
4165 val
= val
& 0xffffff;
4166 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4167 val
, (long)memaddr
);
4170 /* Fill start and end extra bytes of buffer with existing memory data. */
4173 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4174 about coercing an 8 byte integer to a 4 byte pointer. */
4175 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4176 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4184 = ptrace (PTRACE_PEEKTEXT
, pid
,
4185 /* Coerce to a uintptr_t first to avoid potential gcc warning
4186 about coercing an 8 byte integer to a 4 byte pointer. */
4187 (PTRACE_ARG3_TYPE
) (uintptr_t) (addr
+ (count
- 1)
4188 * sizeof (PTRACE_XFER_TYPE
)),
4194 /* Copy data to be written over corresponding part of buffer. */
4196 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4199 /* Write the entire buffer. */
4201 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4204 ptrace (PTRACE_POKETEXT
, pid
,
4205 /* Coerce to a uintptr_t first to avoid potential gcc warning
4206 about coercing an 8 byte integer to a 4 byte pointer. */
4207 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
4208 (PTRACE_ARG4_TYPE
) buffer
[i
]);
4216 /* Non-zero if the kernel supports PTRACE_O_TRACEFORK. */
4217 static int linux_supports_tracefork_flag
;
4220 linux_enable_event_reporting (int pid
)
4222 if (!linux_supports_tracefork_flag
)
4225 ptrace (PTRACE_SETOPTIONS
, pid
, 0, (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
4228 /* Helper functions for linux_test_for_tracefork, called via clone (). */
4231 linux_tracefork_grandchild (void *arg
)
4236 #define STACK_SIZE 4096
4239 linux_tracefork_child (void *arg
)
4241 ptrace (PTRACE_TRACEME
, 0, 0, 0);
4242 kill (getpid (), SIGSTOP
);
4244 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4247 linux_tracefork_grandchild (NULL
);
4249 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4252 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
4253 CLONE_VM
| SIGCHLD
, NULL
);
4255 clone (linux_tracefork_grandchild
, (char *) arg
+ STACK_SIZE
,
4256 CLONE_VM
| SIGCHLD
, NULL
);
4259 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4264 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
4265 sure that we can enable the option, and that it had the desired
4269 linux_test_for_tracefork (void)
4271 int child_pid
, ret
, status
;
4273 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4274 char *stack
= xmalloc (STACK_SIZE
* 4);
4275 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4277 linux_supports_tracefork_flag
= 0;
4279 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4281 child_pid
= fork ();
4283 linux_tracefork_child (NULL
);
4285 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4287 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
4289 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
4290 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4291 #else /* !__ia64__ */
4292 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
4293 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4294 #endif /* !__ia64__ */
4296 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4298 if (child_pid
== -1)
4299 perror_with_name ("clone");
4301 ret
= my_waitpid (child_pid
, &status
, 0);
4303 perror_with_name ("waitpid");
4304 else if (ret
!= child_pid
)
4305 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
4306 if (! WIFSTOPPED (status
))
4307 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
4309 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
4310 (PTRACE_ARG4_TYPE
) PTRACE_O_TRACEFORK
);
4313 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4316 warning ("linux_test_for_tracefork: failed to kill child");
4320 ret
= my_waitpid (child_pid
, &status
, 0);
4321 if (ret
!= child_pid
)
4322 warning ("linux_test_for_tracefork: failed to wait for killed child");
4323 else if (!WIFSIGNALED (status
))
4324 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
4325 "killed child", status
);
4330 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
4332 warning ("linux_test_for_tracefork: failed to resume child");
4334 ret
= my_waitpid (child_pid
, &status
, 0);
4336 if (ret
== child_pid
&& WIFSTOPPED (status
)
4337 && status
>> 16 == PTRACE_EVENT_FORK
)
4340 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
4341 if (ret
== 0 && second_pid
!= 0)
4345 linux_supports_tracefork_flag
= 1;
4346 my_waitpid (second_pid
, &second_status
, 0);
4347 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
4349 warning ("linux_test_for_tracefork: failed to kill second child");
4350 my_waitpid (second_pid
, &status
, 0);
4354 warning ("linux_test_for_tracefork: unexpected result from waitpid "
4355 "(%d, status 0x%x)", ret
, status
);
4359 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4361 warning ("linux_test_for_tracefork: failed to kill child");
4362 my_waitpid (child_pid
, &status
, 0);
4364 while (WIFSTOPPED (status
));
4366 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4368 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4373 linux_look_up_symbols (void)
4375 #ifdef USE_THREAD_DB
4376 struct process_info
*proc
= current_process ();
4378 if (proc
->private->thread_db
!= NULL
)
4381 /* If the kernel supports tracing forks then it also supports tracing
4382 clones, and then we don't need to use the magic thread event breakpoint
4383 to learn about threads. */
4384 thread_db_init (!linux_supports_tracefork_flag
);
4389 linux_request_interrupt (void)
4391 extern unsigned long signal_pid
;
4393 if (!ptid_equal (cont_thread
, null_ptid
)
4394 && !ptid_equal (cont_thread
, minus_one_ptid
))
4396 struct lwp_info
*lwp
;
4399 lwp
= get_thread_lwp (current_inferior
);
4400 lwpid
= lwpid_of (lwp
);
4401 kill_lwp (lwpid
, SIGINT
);
4404 kill_lwp (signal_pid
, SIGINT
);
4407 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4408 to debugger memory starting at MYADDR. */
4411 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4413 char filename
[PATH_MAX
];
4415 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4417 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4419 fd
= open (filename
, O_RDONLY
);
4423 if (offset
!= (CORE_ADDR
) 0
4424 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4427 n
= read (fd
, myaddr
, len
);
4434 /* These breakpoint and watchpoint related wrapper functions simply
4435 pass on the function call if the target has registered a
4436 corresponding function. */
4439 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
4441 if (the_low_target
.insert_point
!= NULL
)
4442 return the_low_target
.insert_point (type
, addr
, len
);
4444 /* Unsupported (see target.h). */
4449 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
4451 if (the_low_target
.remove_point
!= NULL
)
4452 return the_low_target
.remove_point (type
, addr
, len
);
4454 /* Unsupported (see target.h). */
4459 linux_stopped_by_watchpoint (void)
4461 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4463 return lwp
->stopped_by_watchpoint
;
4467 linux_stopped_data_address (void)
4469 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4471 return lwp
->stopped_data_address
;
4474 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4475 #if defined(__mcoldfire__)
4476 /* These should really be defined in the kernel's ptrace.h header. */
4477 #define PT_TEXT_ADDR 49*4
4478 #define PT_DATA_ADDR 50*4
4479 #define PT_TEXT_END_ADDR 51*4
4481 #define PT_TEXT_ADDR 220
4482 #define PT_TEXT_END_ADDR 224
4483 #define PT_DATA_ADDR 228
4484 #elif defined(__TMS320C6X__)
4485 #define PT_TEXT_ADDR (0x10000*4)
4486 #define PT_DATA_ADDR (0x10004*4)
4487 #define PT_TEXT_END_ADDR (0x10008*4)
4490 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4491 to tell gdb about. */
4494 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
4496 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
4497 unsigned long text
, text_end
, data
;
4498 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4502 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
4503 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
4504 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
4508 /* Both text and data offsets produced at compile-time (and so
4509 used by gdb) are relative to the beginning of the program,
4510 with the data segment immediately following the text segment.
4511 However, the actual runtime layout in memory may put the data
4512 somewhere else, so when we send gdb a data base-address, we
4513 use the real data base address and subtract the compile-time
4514 data base-address from it (which is just the length of the
4515 text segment). BSS immediately follows data in both
4518 *data_p
= data
- (text_end
- text
);
4528 linux_qxfer_osdata (const char *annex
,
4529 unsigned char *readbuf
, unsigned const char *writebuf
,
4530 CORE_ADDR offset
, int len
)
4532 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
4535 /* Convert a native/host siginfo object, into/from the siginfo in the
4536 layout of the inferiors' architecture. */
4539 siginfo_fixup (struct siginfo
*siginfo
, void *inf_siginfo
, int direction
)
4543 if (the_low_target
.siginfo_fixup
!= NULL
)
4544 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4546 /* If there was no callback, or the callback didn't do anything,
4547 then just do a straight memcpy. */
4551 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
4553 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
4558 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
4559 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
4562 struct siginfo siginfo
;
4563 char inf_siginfo
[sizeof (struct siginfo
)];
4565 if (current_inferior
== NULL
)
4568 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4571 fprintf (stderr
, "%s siginfo for lwp %d.\n",
4572 readbuf
!= NULL
? "Reading" : "Writing",
4575 if (offset
>= sizeof (siginfo
))
4578 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
4581 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4582 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4583 inferior with a 64-bit GDBSERVER should look the same as debugging it
4584 with a 32-bit GDBSERVER, we need to convert it. */
4585 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4587 if (offset
+ len
> sizeof (siginfo
))
4588 len
= sizeof (siginfo
) - offset
;
4590 if (readbuf
!= NULL
)
4591 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4594 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4596 /* Convert back to ptrace layout before flushing it out. */
4597 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4599 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
4606 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4607 so we notice when children change state; as the handler for the
4608 sigsuspend in my_waitpid. */
4611 sigchld_handler (int signo
)
4613 int old_errno
= errno
;
4619 /* fprintf is not async-signal-safe, so call write
4621 if (write (2, "sigchld_handler\n",
4622 sizeof ("sigchld_handler\n") - 1) < 0)
4623 break; /* just ignore */
4627 if (target_is_async_p ())
4628 async_file_mark (); /* trigger a linux_wait */
4634 linux_supports_non_stop (void)
4640 linux_async (int enable
)
4642 int previous
= (linux_event_pipe
[0] != -1);
4645 fprintf (stderr
, "linux_async (%d), previous=%d\n",
4648 if (previous
!= enable
)
4651 sigemptyset (&mask
);
4652 sigaddset (&mask
, SIGCHLD
);
4654 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
4658 if (pipe (linux_event_pipe
) == -1)
4659 fatal ("creating event pipe failed.");
4661 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
4662 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
4664 /* Register the event loop handler. */
4665 add_file_handler (linux_event_pipe
[0],
4666 handle_target_event
, NULL
);
4668 /* Always trigger a linux_wait. */
4673 delete_file_handler (linux_event_pipe
[0]);
4675 close (linux_event_pipe
[0]);
4676 close (linux_event_pipe
[1]);
4677 linux_event_pipe
[0] = -1;
4678 linux_event_pipe
[1] = -1;
4681 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
4688 linux_start_non_stop (int nonstop
)
4690 /* Register or unregister from event-loop accordingly. */
4691 linux_async (nonstop
);
4696 linux_supports_multi_process (void)
4702 linux_supports_disable_randomization (void)
4704 #ifdef HAVE_PERSONALITY
4711 /* Enumerate spufs IDs for process PID. */
4713 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
4719 struct dirent
*entry
;
4721 sprintf (path
, "/proc/%ld/fd", pid
);
4722 dir
= opendir (path
);
4727 while ((entry
= readdir (dir
)) != NULL
)
4733 fd
= atoi (entry
->d_name
);
4737 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
4738 if (stat (path
, &st
) != 0)
4740 if (!S_ISDIR (st
.st_mode
))
4743 if (statfs (path
, &stfs
) != 0)
4745 if (stfs
.f_type
!= SPUFS_MAGIC
)
4748 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
4750 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
4760 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
4761 object type, using the /proc file system. */
4763 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
4764 unsigned const char *writebuf
,
4765 CORE_ADDR offset
, int len
)
4767 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
4772 if (!writebuf
&& !readbuf
)
4780 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
4783 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
4784 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
4789 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4796 ret
= write (fd
, writebuf
, (size_t) len
);
4798 ret
= read (fd
, readbuf
, (size_t) len
);
4804 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
4805 struct target_loadseg
4807 /* Core address to which the segment is mapped. */
4809 /* VMA recorded in the program header. */
4811 /* Size of this segment in memory. */
4815 # if defined PT_GETDSBT
4816 struct target_loadmap
4818 /* Protocol version number, must be zero. */
4820 /* Pointer to the DSBT table, its size, and the DSBT index. */
4821 unsigned *dsbt_table
;
4822 unsigned dsbt_size
, dsbt_index
;
4823 /* Number of segments in this map. */
4825 /* The actual memory map. */
4826 struct target_loadseg segs
[/*nsegs*/];
4828 # define LINUX_LOADMAP PT_GETDSBT
4829 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
4830 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
4832 struct target_loadmap
4834 /* Protocol version number, must be zero. */
4836 /* Number of segments in this map. */
4838 /* The actual memory map. */
4839 struct target_loadseg segs
[/*nsegs*/];
4841 # define LINUX_LOADMAP PTRACE_GETFDPIC
4842 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
4843 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
4847 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
4848 unsigned char *myaddr
, unsigned int len
)
4850 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4852 struct target_loadmap
*data
= NULL
;
4853 unsigned int actual_length
, copy_length
;
4855 if (strcmp (annex
, "exec") == 0)
4856 addr
= (int) LINUX_LOADMAP_EXEC
;
4857 else if (strcmp (annex
, "interp") == 0)
4858 addr
= (int) LINUX_LOADMAP_INTERP
;
4862 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
4868 actual_length
= sizeof (struct target_loadmap
)
4869 + sizeof (struct target_loadseg
) * data
->nsegs
;
4871 if (offset
< 0 || offset
> actual_length
)
4874 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
4875 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
4879 # define linux_read_loadmap NULL
4880 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
4883 linux_process_qsupported (const char *query
)
4885 if (the_low_target
.process_qsupported
!= NULL
)
4886 the_low_target
.process_qsupported (query
);
4890 linux_supports_tracepoints (void)
4892 if (*the_low_target
.supports_tracepoints
== NULL
)
4895 return (*the_low_target
.supports_tracepoints
) ();
4899 linux_read_pc (struct regcache
*regcache
)
4901 if (the_low_target
.get_pc
== NULL
)
4904 return (*the_low_target
.get_pc
) (regcache
);
4908 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
4910 gdb_assert (the_low_target
.set_pc
!= NULL
);
4912 (*the_low_target
.set_pc
) (regcache
, pc
);
4916 linux_thread_stopped (struct thread_info
*thread
)
4918 return get_thread_lwp (thread
)->stopped
;
4921 /* This exposes stop-all-threads functionality to other modules. */
4924 linux_pause_all (int freeze
)
4926 stop_all_lwps (freeze
, NULL
);
4929 /* This exposes unstop-all-threads functionality to other gdbserver
4933 linux_unpause_all (int unfreeze
)
4935 unstop_all_lwps (unfreeze
, NULL
);
4939 linux_prepare_to_access_memory (void)
4941 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
4944 linux_pause_all (1);
4949 linux_done_accessing_memory (void)
4951 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
4954 linux_unpause_all (1);
4958 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
4959 CORE_ADDR collector
,
4962 CORE_ADDR
*jump_entry
,
4963 CORE_ADDR
*trampoline
,
4964 ULONGEST
*trampoline_size
,
4965 unsigned char *jjump_pad_insn
,
4966 ULONGEST
*jjump_pad_insn_size
,
4967 CORE_ADDR
*adjusted_insn_addr
,
4968 CORE_ADDR
*adjusted_insn_addr_end
,
4971 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
4972 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
4973 jump_entry
, trampoline
, trampoline_size
,
4974 jjump_pad_insn
, jjump_pad_insn_size
,
4975 adjusted_insn_addr
, adjusted_insn_addr_end
,
4979 static struct emit_ops
*
4980 linux_emit_ops (void)
4982 if (the_low_target
.emit_ops
!= NULL
)
4983 return (*the_low_target
.emit_ops
) ();
4989 linux_get_min_fast_tracepoint_insn_len (void)
4991 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
4994 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
4997 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
4998 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5000 char filename
[PATH_MAX
];
5002 const int auxv_size
= is_elf64
5003 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5004 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5006 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5008 fd
= open (filename
, O_RDONLY
);
5014 while (read (fd
, buf
, auxv_size
) == auxv_size
5015 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5019 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5021 switch (aux
->a_type
)
5024 *phdr_memaddr
= aux
->a_un
.a_val
;
5027 *num_phdr
= aux
->a_un
.a_val
;
5033 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5035 switch (aux
->a_type
)
5038 *phdr_memaddr
= aux
->a_un
.a_val
;
5041 *num_phdr
= aux
->a_un
.a_val
;
5049 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5051 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5052 "phdr_memaddr = %ld, phdr_num = %d",
5053 (long) *phdr_memaddr
, *num_phdr
);
5060 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5063 get_dynamic (const int pid
, const int is_elf64
)
5065 CORE_ADDR phdr_memaddr
, relocation
;
5067 unsigned char *phdr_buf
;
5068 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5070 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5073 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5074 phdr_buf
= alloca (num_phdr
* phdr_size
);
5076 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5079 /* Compute relocation: it is expected to be 0 for "regular" executables,
5080 non-zero for PIE ones. */
5082 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5085 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5087 if (p
->p_type
== PT_PHDR
)
5088 relocation
= phdr_memaddr
- p
->p_vaddr
;
5092 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5094 if (p
->p_type
== PT_PHDR
)
5095 relocation
= phdr_memaddr
- p
->p_vaddr
;
5098 if (relocation
== -1)
5100 warning ("Unexpected missing PT_PHDR");
5104 for (i
= 0; i
< num_phdr
; i
++)
5108 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5110 if (p
->p_type
== PT_DYNAMIC
)
5111 return p
->p_vaddr
+ relocation
;
5115 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5117 if (p
->p_type
== PT_DYNAMIC
)
5118 return p
->p_vaddr
+ relocation
;
5125 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5126 can be 0 if the inferior does not yet have the library list initialized. */
5129 get_r_debug (const int pid
, const int is_elf64
)
5131 CORE_ADDR dynamic_memaddr
;
5132 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5133 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5135 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5136 if (dynamic_memaddr
== 0)
5137 return (CORE_ADDR
) -1;
5139 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5143 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5145 if (dyn
->d_tag
== DT_DEBUG
)
5146 return dyn
->d_un
.d_val
;
5148 if (dyn
->d_tag
== DT_NULL
)
5153 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5155 if (dyn
->d_tag
== DT_DEBUG
)
5156 return dyn
->d_un
.d_val
;
5158 if (dyn
->d_tag
== DT_NULL
)
5162 dynamic_memaddr
+= dyn_size
;
5165 return (CORE_ADDR
) -1;
5168 /* Read one pointer from MEMADDR in the inferior. */
5171 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5174 return linux_read_memory (memaddr
, (unsigned char *) ptr
, ptr_size
);
5177 struct link_map_offsets
5179 /* Offset and size of r_debug.r_version. */
5180 int r_version_offset
;
5182 /* Offset and size of r_debug.r_map. */
5185 /* Offset to l_addr field in struct link_map. */
5188 /* Offset to l_name field in struct link_map. */
5191 /* Offset to l_ld field in struct link_map. */
5194 /* Offset to l_next field in struct link_map. */
5197 /* Offset to l_prev field in struct link_map. */
5201 /* Construct qXfer:libraries:read reply. */
5204 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5205 unsigned const char *writebuf
,
5206 CORE_ADDR offset
, int len
)
5209 unsigned document_len
;
5210 struct process_info_private
*const priv
= current_process ()->private;
5211 char filename
[PATH_MAX
];
5214 static const struct link_map_offsets lmo_32bit_offsets
=
5216 0, /* r_version offset. */
5217 4, /* r_debug.r_map offset. */
5218 0, /* l_addr offset in link_map. */
5219 4, /* l_name offset in link_map. */
5220 8, /* l_ld offset in link_map. */
5221 12, /* l_next offset in link_map. */
5222 16 /* l_prev offset in link_map. */
5225 static const struct link_map_offsets lmo_64bit_offsets
=
5227 0, /* r_version offset. */
5228 8, /* r_debug.r_map offset. */
5229 0, /* l_addr offset in link_map. */
5230 8, /* l_name offset in link_map. */
5231 16, /* l_ld offset in link_map. */
5232 24, /* l_next offset in link_map. */
5233 32 /* l_prev offset in link_map. */
5235 const struct link_map_offsets
*lmo
;
5237 if (writebuf
!= NULL
)
5239 if (readbuf
== NULL
)
5242 pid
= lwpid_of (get_thread_lwp (current_inferior
));
5243 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5244 is_elf64
= elf_64_file_p (filename
);
5245 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5247 if (priv
->r_debug
== 0)
5248 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5250 if (priv
->r_debug
== (CORE_ADDR
) -1 || priv
->r_debug
== 0)
5252 document
= xstrdup ("<library-list-svr4 version=\"1.0\"/>\n");
5256 int allocated
= 1024;
5258 const int ptr_size
= is_elf64
? 8 : 4;
5259 CORE_ADDR lm_addr
, lm_prev
, l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5260 int r_version
, header_done
= 0;
5262 document
= xmalloc (allocated
);
5263 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5264 p
= document
+ strlen (document
);
5267 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5268 (unsigned char *) &r_version
,
5269 sizeof (r_version
)) != 0
5272 warning ("unexpected r_debug version %d", r_version
);
5276 if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5277 &lm_addr
, ptr_size
) != 0)
5279 warning ("unable to read r_map from 0x%lx",
5280 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5285 while (read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5286 &l_name
, ptr_size
) == 0
5287 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5288 &l_addr
, ptr_size
) == 0
5289 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5290 &l_ld
, ptr_size
) == 0
5291 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5292 &l_prev
, ptr_size
) == 0
5293 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5294 &l_next
, ptr_size
) == 0)
5296 unsigned char libname
[PATH_MAX
];
5298 if (lm_prev
!= l_prev
)
5300 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5301 (long) lm_prev
, (long) l_prev
);
5305 /* Not checking for error because reading may stop before
5306 we've got PATH_MAX worth of characters. */
5308 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5309 libname
[sizeof (libname
) - 1] = '\0';
5310 if (libname
[0] != '\0')
5312 /* 6x the size for xml_escape_text below. */
5313 size_t len
= 6 * strlen ((char *) libname
);
5318 /* Terminate `<library-list-svr4'. */
5323 while (allocated
< p
- document
+ len
+ 200)
5325 /* Expand to guarantee sufficient storage. */
5326 uintptr_t document_len
= p
- document
;
5328 document
= xrealloc (document
, 2 * allocated
);
5330 p
= document
+ document_len
;
5333 name
= xml_escape_text ((char *) libname
);
5334 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
5335 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5336 name
, (unsigned long) lm_addr
,
5337 (unsigned long) l_addr
, (unsigned long) l_ld
);
5340 else if (lm_prev
== 0)
5342 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5353 strcpy (p
, "</library-list-svr4>");
5356 document_len
= strlen (document
);
5357 if (offset
< document_len
)
5358 document_len
-= offset
;
5361 if (len
> document_len
)
5364 memcpy (readbuf
, document
+ offset
, len
);
5370 static struct target_ops linux_target_ops
= {
5371 linux_create_inferior
,
5380 linux_fetch_registers
,
5381 linux_store_registers
,
5382 linux_prepare_to_access_memory
,
5383 linux_done_accessing_memory
,
5386 linux_look_up_symbols
,
5387 linux_request_interrupt
,
5391 linux_stopped_by_watchpoint
,
5392 linux_stopped_data_address
,
5393 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
5398 #ifdef USE_THREAD_DB
5399 thread_db_get_tls_address
,
5404 hostio_last_error_from_errno
,
5407 linux_supports_non_stop
,
5409 linux_start_non_stop
,
5410 linux_supports_multi_process
,
5411 #ifdef USE_THREAD_DB
5412 thread_db_handle_monitor_command
,
5416 linux_common_core_of_thread
,
5418 linux_process_qsupported
,
5419 linux_supports_tracepoints
,
5422 linux_thread_stopped
,
5426 linux_cancel_breakpoints
,
5427 linux_stabilize_threads
,
5428 linux_install_fast_tracepoint_jump_pad
,
5430 linux_supports_disable_randomization
,
5431 linux_get_min_fast_tracepoint_insn_len
,
5432 linux_qxfer_libraries_svr4
,
5436 linux_init_signals ()
5438 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5439 to find what the cancel signal actually is. */
5440 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
5441 signal (__SIGRTMIN
+1, SIG_IGN
);
5446 initialize_low (void)
5448 struct sigaction sigchld_action
;
5449 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
5450 set_target_ops (&linux_target_ops
);
5451 set_breakpoint_data (the_low_target
.breakpoint
,
5452 the_low_target
.breakpoint_len
);
5453 linux_init_signals ();
5454 linux_test_for_tracefork ();
5455 #ifdef HAVE_LINUX_REGSETS
5456 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
5458 disabled_regsets
= xmalloc (num_regsets
);
5461 sigchld_action
.sa_handler
= sigchld_handler
;
5462 sigemptyset (&sigchld_action
.sa_mask
);
5463 sigchld_action
.sa_flags
= SA_RESTART
;
5464 sigaction (SIGCHLD
, &sigchld_action
, NULL
);