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 (ptid_t ptid
, int *wstat
, int options
)
1574 struct lwp_info
*event_child
, *requested_child
;
1578 requested_child
= NULL
;
1580 /* Check for a lwp with a pending status. */
1582 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
1584 event_child
= (struct lwp_info
*)
1585 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1586 if (debug_threads
&& event_child
)
1587 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1591 requested_child
= find_lwp_pid (ptid
);
1593 if (!stopping_threads
1594 && requested_child
->status_pending_p
1595 && requested_child
->collecting_fast_tracepoint
)
1597 enqueue_one_deferred_signal (requested_child
,
1598 &requested_child
->status_pending
);
1599 requested_child
->status_pending_p
= 0;
1600 requested_child
->status_pending
= 0;
1601 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
1604 if (requested_child
->suspended
1605 && requested_child
->status_pending_p
)
1606 fatal ("requesting an event out of a suspended child?");
1608 if (requested_child
->status_pending_p
)
1609 event_child
= requested_child
;
1612 if (event_child
!= NULL
)
1615 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1616 lwpid_of (event_child
), event_child
->status_pending
);
1617 *wstat
= event_child
->status_pending
;
1618 event_child
->status_pending_p
= 0;
1619 event_child
->status_pending
= 0;
1620 current_inferior
= get_lwp_thread (event_child
);
1621 return lwpid_of (event_child
);
1624 if (ptid_is_pid (ptid
))
1626 /* A request to wait for a specific tgid. This is not possible
1627 with waitpid, so instead, we wait for any child, and leave
1628 children we're not interested in right now with a pending
1629 status to report later. */
1630 wait_ptid
= minus_one_ptid
;
1635 /* We only enter this loop if no process has a pending wait status. Thus
1636 any action taken in response to a wait status inside this loop is
1637 responding as soon as we detect the status, not after any pending
1641 event_child
= linux_wait_for_lwp (wait_ptid
, wstat
, options
);
1643 if ((options
& WNOHANG
) && event_child
== NULL
)
1646 fprintf (stderr
, "WNOHANG set, no event found\n");
1650 if (event_child
== NULL
)
1651 error ("event from unknown child");
1653 if (ptid_is_pid (ptid
)
1654 && ptid_get_pid (ptid
) != ptid_get_pid (ptid_of (event_child
)))
1656 if (! WIFSTOPPED (*wstat
))
1657 mark_lwp_dead (event_child
, *wstat
);
1660 event_child
->status_pending_p
= 1;
1661 event_child
->status_pending
= *wstat
;
1666 current_inferior
= get_lwp_thread (event_child
);
1668 /* Check for thread exit. */
1669 if (! WIFSTOPPED (*wstat
))
1672 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1674 /* If the last thread is exiting, just return. */
1675 if (last_thread_of_process_p (current_inferior
))
1678 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1679 lwpid_of (event_child
));
1680 return lwpid_of (event_child
);
1685 current_inferior
= (struct thread_info
*) all_threads
.head
;
1687 fprintf (stderr
, "Current inferior is now %ld\n",
1688 lwpid_of (get_thread_lwp (current_inferior
)));
1692 current_inferior
= NULL
;
1694 fprintf (stderr
, "Current inferior is now <NULL>\n");
1697 /* If we were waiting for this particular child to do something...
1698 well, it did something. */
1699 if (requested_child
!= NULL
)
1701 int lwpid
= lwpid_of (event_child
);
1703 /* Cancel the step-over operation --- the thread that
1704 started it is gone. */
1705 if (finish_step_over (event_child
))
1706 unstop_all_lwps (1, event_child
);
1707 delete_lwp (event_child
);
1711 delete_lwp (event_child
);
1713 /* Wait for a more interesting event. */
1717 if (event_child
->must_set_ptrace_flags
)
1719 linux_enable_event_reporting (lwpid_of (event_child
));
1720 event_child
->must_set_ptrace_flags
= 0;
1723 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1724 && *wstat
>> 16 != 0)
1726 handle_extended_wait (event_child
, *wstat
);
1730 if (WIFSTOPPED (*wstat
)
1731 && WSTOPSIG (*wstat
) == SIGSTOP
1732 && event_child
->stop_expected
)
1737 fprintf (stderr
, "Expected stop.\n");
1738 event_child
->stop_expected
= 0;
1740 should_stop
= (current_inferior
->last_resume_kind
== resume_stop
1741 || stopping_threads
);
1745 linux_resume_one_lwp (event_child
,
1746 event_child
->stepping
, 0, NULL
);
1751 return lwpid_of (event_child
);
1758 /* Count the LWP's that have had events. */
1761 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
1763 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1764 struct thread_info
*thread
= get_lwp_thread (lp
);
1767 gdb_assert (count
!= NULL
);
1769 /* Count only resumed LWPs that have a SIGTRAP event pending that
1770 should be reported to GDB. */
1771 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1772 && thread
->last_resume_kind
!= resume_stop
1773 && lp
->status_pending_p
1774 && WIFSTOPPED (lp
->status_pending
)
1775 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1776 && !breakpoint_inserted_here (lp
->stop_pc
))
1782 /* Select the LWP (if any) that is currently being single-stepped. */
1785 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1787 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1788 struct thread_info
*thread
= get_lwp_thread (lp
);
1790 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1791 && thread
->last_resume_kind
== resume_step
1792 && lp
->status_pending_p
)
1798 /* Select the Nth LWP that has had a SIGTRAP event that should be
1802 select_event_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
);
1806 int *selector
= data
;
1808 gdb_assert (selector
!= NULL
);
1810 /* Select only resumed LWPs that have a SIGTRAP event pending. */
1811 if (thread
->last_resume_kind
!= resume_stop
1812 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1813 && lp
->status_pending_p
1814 && WIFSTOPPED (lp
->status_pending
)
1815 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1816 && !breakpoint_inserted_here (lp
->stop_pc
))
1817 if ((*selector
)-- == 0)
1824 cancel_breakpoints_callback (struct inferior_list_entry
*entry
, void *data
)
1826 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1827 struct thread_info
*thread
= get_lwp_thread (lp
);
1828 struct lwp_info
*event_lp
= data
;
1830 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
1834 /* If a LWP other than the LWP that we're reporting an event for has
1835 hit a GDB breakpoint (as opposed to some random trap signal),
1836 then just arrange for it to hit it again later. We don't keep
1837 the SIGTRAP status and don't forward the SIGTRAP signal to the
1838 LWP. We will handle the current event, eventually we will resume
1839 all LWPs, and this one will get its breakpoint trap again.
1841 If we do not do this, then we run the risk that the user will
1842 delete or disable the breakpoint, but the LWP will have already
1845 if (thread
->last_resume_kind
!= resume_stop
1846 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1847 && lp
->status_pending_p
1848 && WIFSTOPPED (lp
->status_pending
)
1849 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1851 && !lp
->stopped_by_watchpoint
1852 && cancel_breakpoint (lp
))
1853 /* Throw away the SIGTRAP. */
1854 lp
->status_pending_p
= 0;
1860 linux_cancel_breakpoints (void)
1862 find_inferior (&all_lwps
, cancel_breakpoints_callback
, NULL
);
1865 /* Select one LWP out of those that have events pending. */
1868 select_event_lwp (struct lwp_info
**orig_lp
)
1871 int random_selector
;
1872 struct lwp_info
*event_lp
;
1874 /* Give preference to any LWP that is being single-stepped. */
1876 = (struct lwp_info
*) find_inferior (&all_lwps
,
1877 select_singlestep_lwp_callback
, NULL
);
1878 if (event_lp
!= NULL
)
1882 "SEL: Select single-step %s\n",
1883 target_pid_to_str (ptid_of (event_lp
)));
1887 /* No single-stepping LWP. Select one at random, out of those
1888 which have had SIGTRAP events. */
1890 /* First see how many SIGTRAP events we have. */
1891 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
1893 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
1894 random_selector
= (int)
1895 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
1897 if (debug_threads
&& num_events
> 1)
1899 "SEL: Found %d SIGTRAP events, selecting #%d\n",
1900 num_events
, random_selector
);
1902 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
1903 select_event_lwp_callback
,
1907 if (event_lp
!= NULL
)
1909 /* Switch the event LWP. */
1910 *orig_lp
= event_lp
;
1914 /* Decrement the suspend count of an LWP. */
1917 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
1919 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1921 /* Ignore EXCEPT. */
1927 gdb_assert (lwp
->suspended
>= 0);
1931 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
1935 unsuspend_all_lwps (struct lwp_info
*except
)
1937 find_inferior (&all_lwps
, unsuspend_one_lwp
, except
);
1940 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
1941 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
1943 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
1944 static ptid_t
linux_wait_1 (ptid_t ptid
,
1945 struct target_waitstatus
*ourstatus
,
1946 int target_options
);
1948 /* Stabilize threads (move out of jump pads).
1950 If a thread is midway collecting a fast tracepoint, we need to
1951 finish the collection and move it out of the jump pad before
1952 reporting the signal.
1954 This avoids recursion while collecting (when a signal arrives
1955 midway, and the signal handler itself collects), which would trash
1956 the trace buffer. In case the user set a breakpoint in a signal
1957 handler, this avoids the backtrace showing the jump pad, etc..
1958 Most importantly, there are certain things we can't do safely if
1959 threads are stopped in a jump pad (or in its callee's). For
1962 - starting a new trace run. A thread still collecting the
1963 previous run, could trash the trace buffer when resumed. The trace
1964 buffer control structures would have been reset but the thread had
1965 no way to tell. The thread could even midway memcpy'ing to the
1966 buffer, which would mean that when resumed, it would clobber the
1967 trace buffer that had been set for a new run.
1969 - we can't rewrite/reuse the jump pads for new tracepoints
1970 safely. Say you do tstart while a thread is stopped midway while
1971 collecting. When the thread is later resumed, it finishes the
1972 collection, and returns to the jump pad, to execute the original
1973 instruction that was under the tracepoint jump at the time the
1974 older run had been started. If the jump pad had been rewritten
1975 since for something else in the new run, the thread would now
1976 execute the wrong / random instructions. */
1979 linux_stabilize_threads (void)
1981 struct thread_info
*save_inferior
;
1982 struct lwp_info
*lwp_stuck
;
1985 = (struct lwp_info
*) find_inferior (&all_lwps
,
1986 stuck_in_jump_pad_callback
, NULL
);
1987 if (lwp_stuck
!= NULL
)
1990 fprintf (stderr
, "can't stabilize, LWP %ld is stuck in jump pad\n",
1991 lwpid_of (lwp_stuck
));
1995 save_inferior
= current_inferior
;
1997 stabilizing_threads
= 1;
2000 for_each_inferior (&all_lwps
, move_out_of_jump_pad_callback
);
2002 /* Loop until all are stopped out of the jump pads. */
2003 while (find_inferior (&all_lwps
, lwp_running
, NULL
) != NULL
)
2005 struct target_waitstatus ourstatus
;
2006 struct lwp_info
*lwp
;
2009 /* Note that we go through the full wait even loop. While
2010 moving threads out of jump pad, we need to be able to step
2011 over internal breakpoints and such. */
2012 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2014 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2016 lwp
= get_thread_lwp (current_inferior
);
2021 if (ourstatus
.value
.sig
!= TARGET_SIGNAL_0
2022 || current_inferior
->last_resume_kind
== resume_stop
)
2024 wstat
= W_STOPCODE (target_signal_to_host (ourstatus
.value
.sig
));
2025 enqueue_one_deferred_signal (lwp
, &wstat
);
2030 find_inferior (&all_lwps
, unsuspend_one_lwp
, NULL
);
2032 stabilizing_threads
= 0;
2034 current_inferior
= save_inferior
;
2039 = (struct lwp_info
*) find_inferior (&all_lwps
,
2040 stuck_in_jump_pad_callback
, NULL
);
2041 if (lwp_stuck
!= NULL
)
2042 fprintf (stderr
, "couldn't stabilize, LWP %ld got stuck in jump pad\n",
2043 lwpid_of (lwp_stuck
));
2047 /* Wait for process, returns status. */
2050 linux_wait_1 (ptid_t ptid
,
2051 struct target_waitstatus
*ourstatus
, int target_options
)
2054 struct lwp_info
*event_child
;
2057 int step_over_finished
;
2058 int bp_explains_trap
;
2059 int maybe_internal_trap
;
2063 /* Translate generic target options into linux options. */
2065 if (target_options
& TARGET_WNOHANG
)
2069 bp_explains_trap
= 0;
2071 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2073 /* If we were only supposed to resume one thread, only wait for
2074 that thread - if it's still alive. If it died, however - which
2075 can happen if we're coming from the thread death case below -
2076 then we need to make sure we restart the other threads. We could
2077 pick a thread at random or restart all; restarting all is less
2080 && !ptid_equal (cont_thread
, null_ptid
)
2081 && !ptid_equal (cont_thread
, minus_one_ptid
))
2083 struct thread_info
*thread
;
2085 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
2088 /* No stepping, no signal - unless one is pending already, of course. */
2091 struct thread_resume resume_info
;
2092 resume_info
.thread
= minus_one_ptid
;
2093 resume_info
.kind
= resume_continue
;
2094 resume_info
.sig
= 0;
2095 linux_resume (&resume_info
, 1);
2101 if (ptid_equal (step_over_bkpt
, null_ptid
))
2102 pid
= linux_wait_for_event (ptid
, &w
, options
);
2106 fprintf (stderr
, "step_over_bkpt set [%s], doing a blocking wait\n",
2107 target_pid_to_str (step_over_bkpt
));
2108 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2111 if (pid
== 0) /* only if TARGET_WNOHANG */
2114 event_child
= get_thread_lwp (current_inferior
);
2116 /* If we are waiting for a particular child, and it exited,
2117 linux_wait_for_event will return its exit status. Similarly if
2118 the last child exited. If this is not the last child, however,
2119 do not report it as exited until there is a 'thread exited' response
2120 available in the remote protocol. Instead, just wait for another event.
2121 This should be safe, because if the thread crashed we will already
2122 have reported the termination signal to GDB; that should stop any
2123 in-progress stepping operations, etc.
2125 Report the exit status of the last thread to exit. This matches
2126 LinuxThreads' behavior. */
2128 if (last_thread_of_process_p (current_inferior
))
2130 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2134 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2135 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2139 "\nChild exited with retcode = %x \n",
2144 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2145 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
2149 "\nChild terminated with signal = %x \n",
2154 return ptid_of (event_child
);
2159 if (!WIFSTOPPED (w
))
2163 /* If this event was not handled before, and is not a SIGTRAP, we
2164 report it. SIGILL and SIGSEGV are also treated as traps in case
2165 a breakpoint is inserted at the current PC. If this target does
2166 not support internal breakpoints at all, we also report the
2167 SIGTRAP without further processing; it's of no concern to us. */
2169 = (supports_breakpoints ()
2170 && (WSTOPSIG (w
) == SIGTRAP
2171 || ((WSTOPSIG (w
) == SIGILL
2172 || WSTOPSIG (w
) == SIGSEGV
)
2173 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2175 if (maybe_internal_trap
)
2177 /* Handle anything that requires bookkeeping before deciding to
2178 report the event or continue waiting. */
2180 /* First check if we can explain the SIGTRAP with an internal
2181 breakpoint, or if we should possibly report the event to GDB.
2182 Do this before anything that may remove or insert a
2184 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2186 /* We have a SIGTRAP, possibly a step-over dance has just
2187 finished. If so, tweak the state machine accordingly,
2188 reinsert breakpoints and delete any reinsert (software
2189 single-step) breakpoints. */
2190 step_over_finished
= finish_step_over (event_child
);
2192 /* Now invoke the callbacks of any internal breakpoints there. */
2193 check_breakpoints (event_child
->stop_pc
);
2195 /* Handle tracepoint data collecting. This may overflow the
2196 trace buffer, and cause a tracing stop, removing
2198 trace_event
= handle_tracepoints (event_child
);
2200 if (bp_explains_trap
)
2202 /* If we stepped or ran into an internal breakpoint, we've
2203 already handled it. So next time we resume (from this
2204 PC), we should step over it. */
2206 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2208 if (breakpoint_here (event_child
->stop_pc
))
2209 event_child
->need_step_over
= 1;
2214 /* We have some other signal, possibly a step-over dance was in
2215 progress, and it should be cancelled too. */
2216 step_over_finished
= finish_step_over (event_child
);
2219 /* We have all the data we need. Either report the event to GDB, or
2220 resume threads and keep waiting for more. */
2222 /* If we're collecting a fast tracepoint, finish the collection and
2223 move out of the jump pad before delivering a signal. See
2224 linux_stabilize_threads. */
2227 && WSTOPSIG (w
) != SIGTRAP
2228 && supports_fast_tracepoints ()
2229 && in_process_agent_loaded ())
2233 "Got signal %d for LWP %ld. Check if we need "
2234 "to defer or adjust it.\n",
2235 WSTOPSIG (w
), lwpid_of (event_child
));
2237 /* Allow debugging the jump pad itself. */
2238 if (current_inferior
->last_resume_kind
!= resume_step
2239 && maybe_move_out_of_jump_pad (event_child
, &w
))
2241 enqueue_one_deferred_signal (event_child
, &w
);
2245 "Signal %d for LWP %ld deferred (in jump pad)\n",
2246 WSTOPSIG (w
), lwpid_of (event_child
));
2248 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2253 if (event_child
->collecting_fast_tracepoint
)
2257 LWP %ld was trying to move out of the jump pad (%d). \
2258 Check if we're already there.\n",
2259 lwpid_of (event_child
),
2260 event_child
->collecting_fast_tracepoint
);
2264 event_child
->collecting_fast_tracepoint
2265 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2267 if (event_child
->collecting_fast_tracepoint
!= 1)
2269 /* No longer need this breakpoint. */
2270 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2274 "No longer need exit-jump-pad bkpt; removing it."
2275 "stopping all threads momentarily.\n");
2277 /* Other running threads could hit this breakpoint.
2278 We don't handle moribund locations like GDB does,
2279 instead we always pause all threads when removing
2280 breakpoints, so that any step-over or
2281 decr_pc_after_break adjustment is always taken
2282 care of while the breakpoint is still
2284 stop_all_lwps (1, event_child
);
2285 cancel_breakpoints ();
2287 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2288 event_child
->exit_jump_pad_bkpt
= NULL
;
2290 unstop_all_lwps (1, event_child
);
2292 gdb_assert (event_child
->suspended
>= 0);
2296 if (event_child
->collecting_fast_tracepoint
== 0)
2300 "fast tracepoint finished "
2301 "collecting successfully.\n");
2303 /* We may have a deferred signal to report. */
2304 if (dequeue_one_deferred_signal (event_child
, &w
))
2307 fprintf (stderr
, "dequeued one signal.\n");
2312 fprintf (stderr
, "no deferred signals.\n");
2314 if (stabilizing_threads
)
2316 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2317 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2318 return ptid_of (event_child
);
2324 /* Check whether GDB would be interested in this event. */
2326 /* If GDB is not interested in this signal, don't stop other
2327 threads, and don't report it to GDB. Just resume the inferior
2328 right away. We do this for threading-related signals as well as
2329 any that GDB specifically requested we ignore. But never ignore
2330 SIGSTOP if we sent it ourselves, and do not ignore signals when
2331 stepping - they may require special handling to skip the signal
2333 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2336 && current_inferior
->last_resume_kind
!= resume_step
2338 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2339 (current_process ()->private->thread_db
!= NULL
2340 && (WSTOPSIG (w
) == __SIGRTMIN
2341 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2344 (pass_signals
[target_signal_from_host (WSTOPSIG (w
))]
2345 && !(WSTOPSIG (w
) == SIGSTOP
2346 && current_inferior
->last_resume_kind
== resume_stop
))))
2348 siginfo_t info
, *info_p
;
2351 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
2352 WSTOPSIG (w
), lwpid_of (event_child
));
2354 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
2358 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2359 WSTOPSIG (w
), info_p
);
2363 /* If GDB wanted this thread to single step, we always want to
2364 report the SIGTRAP, and let GDB handle it. Watchpoints should
2365 always be reported. So should signals we can't explain. A
2366 SIGTRAP we can't explain could be a GDB breakpoint --- we may or
2367 not support Z0 breakpoints. If we do, we're be able to handle
2368 GDB breakpoints on top of internal breakpoints, by handling the
2369 internal breakpoint and still reporting the event to GDB. If we
2370 don't, we're out of luck, GDB won't see the breakpoint hit. */
2371 report_to_gdb
= (!maybe_internal_trap
2372 || current_inferior
->last_resume_kind
== resume_step
2373 || event_child
->stopped_by_watchpoint
2374 || (!step_over_finished
2375 && !bp_explains_trap
&& !trace_event
)
2376 || gdb_breakpoint_here (event_child
->stop_pc
));
2378 /* We found no reason GDB would want us to stop. We either hit one
2379 of our own breakpoints, or finished an internal step GDB
2380 shouldn't know about. */
2385 if (bp_explains_trap
)
2386 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2387 if (step_over_finished
)
2388 fprintf (stderr
, "Step-over finished.\n");
2390 fprintf (stderr
, "Tracepoint event.\n");
2393 /* We're not reporting this breakpoint to GDB, so apply the
2394 decr_pc_after_break adjustment to the inferior's regcache
2397 if (the_low_target
.set_pc
!= NULL
)
2399 struct regcache
*regcache
2400 = get_thread_regcache (get_lwp_thread (event_child
), 1);
2401 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2404 /* We may have finished stepping over a breakpoint. If so,
2405 we've stopped and suspended all LWPs momentarily except the
2406 stepping one. This is where we resume them all again. We're
2407 going to keep waiting, so use proceed, which handles stepping
2408 over the next breakpoint. */
2410 fprintf (stderr
, "proceeding all threads.\n");
2412 if (step_over_finished
)
2413 unsuspend_all_lwps (event_child
);
2415 proceed_all_lwps ();
2421 if (current_inferior
->last_resume_kind
== resume_step
)
2422 fprintf (stderr
, "GDB wanted to single-step, reporting event.\n");
2423 if (event_child
->stopped_by_watchpoint
)
2424 fprintf (stderr
, "Stopped by watchpoint.\n");
2425 if (gdb_breakpoint_here (event_child
->stop_pc
))
2426 fprintf (stderr
, "Stopped by GDB breakpoint.\n");
2428 fprintf (stderr
, "Hit a non-gdbserver trap event.\n");
2431 /* Alright, we're going to report a stop. */
2433 if (!non_stop
&& !stabilizing_threads
)
2435 /* In all-stop, stop all threads. */
2436 stop_all_lwps (0, NULL
);
2438 /* If we're not waiting for a specific LWP, choose an event LWP
2439 from among those that have had events. Giving equal priority
2440 to all LWPs that have had events helps prevent
2442 if (ptid_equal (ptid
, minus_one_ptid
))
2444 event_child
->status_pending_p
= 1;
2445 event_child
->status_pending
= w
;
2447 select_event_lwp (&event_child
);
2449 event_child
->status_pending_p
= 0;
2450 w
= event_child
->status_pending
;
2453 /* Now that we've selected our final event LWP, cancel any
2454 breakpoints in other LWPs that have hit a GDB breakpoint.
2455 See the comment in cancel_breakpoints_callback to find out
2457 find_inferior (&all_lwps
, cancel_breakpoints_callback
, event_child
);
2459 /* Stabilize threads (move out of jump pads). */
2460 stabilize_threads ();
2464 /* If we just finished a step-over, then all threads had been
2465 momentarily paused. In all-stop, that's fine, we want
2466 threads stopped by now anyway. In non-stop, we need to
2467 re-resume threads that GDB wanted to be running. */
2468 if (step_over_finished
)
2469 unstop_all_lwps (1, event_child
);
2472 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2474 if (current_inferior
->last_resume_kind
== resume_stop
2475 && WSTOPSIG (w
) == SIGSTOP
)
2477 /* A thread that has been requested to stop by GDB with vCont;t,
2478 and it stopped cleanly, so report as SIG0. The use of
2479 SIGSTOP is an implementation detail. */
2480 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2482 else if (current_inferior
->last_resume_kind
== resume_stop
2483 && WSTOPSIG (w
) != SIGSTOP
)
2485 /* A thread that has been requested to stop by GDB with vCont;t,
2486 but, it stopped for other reasons. */
2487 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2491 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2494 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
2497 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
2498 target_pid_to_str (ptid_of (event_child
)),
2500 ourstatus
->value
.sig
);
2502 return ptid_of (event_child
);
2505 /* Get rid of any pending event in the pipe. */
2507 async_file_flush (void)
2513 ret
= read (linux_event_pipe
[0], &buf
, 1);
2514 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
2517 /* Put something in the pipe, so the event loop wakes up. */
2519 async_file_mark (void)
2523 async_file_flush ();
2526 ret
= write (linux_event_pipe
[1], "+", 1);
2527 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
2529 /* Ignore EAGAIN. If the pipe is full, the event loop will already
2530 be awakened anyway. */
2534 linux_wait (ptid_t ptid
,
2535 struct target_waitstatus
*ourstatus
, int target_options
)
2540 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
2542 /* Flush the async file first. */
2543 if (target_is_async_p ())
2544 async_file_flush ();
2546 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
2548 /* If at least one stop was reported, there may be more. A single
2549 SIGCHLD can signal more than one child stop. */
2550 if (target_is_async_p ()
2551 && (target_options
& TARGET_WNOHANG
) != 0
2552 && !ptid_equal (event_ptid
, null_ptid
))
2558 /* Send a signal to an LWP. */
2561 kill_lwp (unsigned long lwpid
, int signo
)
2563 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2564 fails, then we are not using nptl threads and we should be using kill. */
2568 static int tkill_failed
;
2575 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2576 if (errno
!= ENOSYS
)
2583 return kill (lwpid
, signo
);
2587 linux_stop_lwp (struct lwp_info
*lwp
)
2593 send_sigstop (struct lwp_info
*lwp
)
2597 pid
= lwpid_of (lwp
);
2599 /* If we already have a pending stop signal for this process, don't
2601 if (lwp
->stop_expected
)
2604 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
2610 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
2612 lwp
->stop_expected
= 1;
2613 kill_lwp (pid
, SIGSTOP
);
2617 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
2619 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2621 /* Ignore EXCEPT. */
2632 /* Increment the suspend count of an LWP, and stop it, if not stopped
2635 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
2638 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2640 /* Ignore EXCEPT. */
2646 return send_sigstop_callback (entry
, except
);
2650 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
2652 /* It's dead, really. */
2655 /* Store the exit status for later. */
2656 lwp
->status_pending_p
= 1;
2657 lwp
->status_pending
= wstat
;
2659 /* Prevent trying to stop it. */
2662 /* No further stops are expected from a dead lwp. */
2663 lwp
->stop_expected
= 0;
2667 wait_for_sigstop (struct inferior_list_entry
*entry
)
2669 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2670 struct thread_info
*saved_inferior
;
2679 fprintf (stderr
, "wait_for_sigstop: LWP %ld already stopped\n",
2684 saved_inferior
= current_inferior
;
2685 if (saved_inferior
!= NULL
)
2686 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
2688 saved_tid
= null_ptid
; /* avoid bogus unused warning */
2690 ptid
= lwp
->head
.id
;
2693 fprintf (stderr
, "wait_for_sigstop: pulling one event\n");
2695 pid
= linux_wait_for_event (ptid
, &wstat
, __WALL
);
2697 /* If we stopped with a non-SIGSTOP signal, save it for later
2698 and record the pending SIGSTOP. If the process exited, just
2700 if (WIFSTOPPED (wstat
))
2703 fprintf (stderr
, "LWP %ld stopped with signal %d\n",
2704 lwpid_of (lwp
), WSTOPSIG (wstat
));
2706 if (WSTOPSIG (wstat
) != SIGSTOP
)
2709 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
2710 lwpid_of (lwp
), wstat
);
2712 lwp
->status_pending_p
= 1;
2713 lwp
->status_pending
= wstat
;
2719 fprintf (stderr
, "Process %d exited while stopping LWPs\n", pid
);
2721 lwp
= find_lwp_pid (pid_to_ptid (pid
));
2724 /* Leave this status pending for the next time we're able to
2725 report it. In the mean time, we'll report this lwp as
2726 dead to GDB, so GDB doesn't try to read registers and
2727 memory from it. This can only happen if this was the
2728 last thread of the process; otherwise, PID is removed
2729 from the thread tables before linux_wait_for_event
2731 mark_lwp_dead (lwp
, wstat
);
2735 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
2736 current_inferior
= saved_inferior
;
2740 fprintf (stderr
, "Previously current thread died.\n");
2744 /* We can't change the current inferior behind GDB's back,
2745 otherwise, a subsequent command may apply to the wrong
2747 current_inferior
= NULL
;
2751 /* Set a valid thread as current. */
2752 set_desired_inferior (0);
2757 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
2758 move it out, because we need to report the stop event to GDB. For
2759 example, if the user puts a breakpoint in the jump pad, it's
2760 because she wants to debug it. */
2763 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
2765 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2766 struct thread_info
*thread
= get_lwp_thread (lwp
);
2768 gdb_assert (lwp
->suspended
== 0);
2769 gdb_assert (lwp
->stopped
);
2771 /* Allow debugging the jump pad, gdb_collect, etc.. */
2772 return (supports_fast_tracepoints ()
2773 && in_process_agent_loaded ()
2774 && (gdb_breakpoint_here (lwp
->stop_pc
)
2775 || lwp
->stopped_by_watchpoint
2776 || thread
->last_resume_kind
== resume_step
)
2777 && linux_fast_tracepoint_collecting (lwp
, NULL
));
2781 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
2783 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2784 struct thread_info
*thread
= get_lwp_thread (lwp
);
2787 gdb_assert (lwp
->suspended
== 0);
2788 gdb_assert (lwp
->stopped
);
2790 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
2792 /* Allow debugging the jump pad, gdb_collect, etc. */
2793 if (!gdb_breakpoint_here (lwp
->stop_pc
)
2794 && !lwp
->stopped_by_watchpoint
2795 && thread
->last_resume_kind
!= resume_step
2796 && maybe_move_out_of_jump_pad (lwp
, wstat
))
2800 "LWP %ld needs stabilizing (in jump pad)\n",
2805 lwp
->status_pending_p
= 0;
2806 enqueue_one_deferred_signal (lwp
, wstat
);
2810 "Signal %d for LWP %ld deferred "
2812 WSTOPSIG (*wstat
), lwpid_of (lwp
));
2815 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
2822 lwp_running (struct inferior_list_entry
*entry
, void *data
)
2824 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2833 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
2834 If SUSPEND, then also increase the suspend count of every LWP,
2838 stop_all_lwps (int suspend
, struct lwp_info
*except
)
2840 stopping_threads
= 1;
2843 find_inferior (&all_lwps
, suspend_and_send_sigstop_callback
, except
);
2845 find_inferior (&all_lwps
, send_sigstop_callback
, except
);
2846 for_each_inferior (&all_lwps
, wait_for_sigstop
);
2847 stopping_threads
= 0;
2850 /* Resume execution of the inferior process.
2851 If STEP is nonzero, single-step it.
2852 If SIGNAL is nonzero, give it that signal. */
2855 linux_resume_one_lwp (struct lwp_info
*lwp
,
2856 int step
, int signal
, siginfo_t
*info
)
2858 struct thread_info
*saved_inferior
;
2859 int fast_tp_collecting
;
2861 if (lwp
->stopped
== 0)
2864 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
2866 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
2868 /* Cancel actions that rely on GDB not changing the PC (e.g., the
2869 user used the "jump" command, or "set $pc = foo"). */
2870 if (lwp
->stop_pc
!= get_pc (lwp
))
2872 /* Collecting 'while-stepping' actions doesn't make sense
2874 release_while_stepping_state_list (get_lwp_thread (lwp
));
2877 /* If we have pending signals or status, and a new signal, enqueue the
2878 signal. Also enqueue the signal if we are waiting to reinsert a
2879 breakpoint; it will be picked up again below. */
2881 && (lwp
->status_pending_p
2882 || lwp
->pending_signals
!= NULL
2883 || lwp
->bp_reinsert
!= 0
2884 || fast_tp_collecting
))
2886 struct pending_signals
*p_sig
;
2887 p_sig
= xmalloc (sizeof (*p_sig
));
2888 p_sig
->prev
= lwp
->pending_signals
;
2889 p_sig
->signal
= signal
;
2891 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
2893 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
2894 lwp
->pending_signals
= p_sig
;
2897 if (lwp
->status_pending_p
)
2900 fprintf (stderr
, "Not resuming lwp %ld (%s, signal %d, stop %s);"
2901 " has pending status\n",
2902 lwpid_of (lwp
), step
? "step" : "continue", signal
,
2903 lwp
->stop_expected
? "expected" : "not expected");
2907 saved_inferior
= current_inferior
;
2908 current_inferior
= get_lwp_thread (lwp
);
2911 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
2912 lwpid_of (lwp
), step
? "step" : "continue", signal
,
2913 lwp
->stop_expected
? "expected" : "not expected");
2915 /* This bit needs some thinking about. If we get a signal that
2916 we must report while a single-step reinsert is still pending,
2917 we often end up resuming the thread. It might be better to
2918 (ew) allow a stack of pending events; then we could be sure that
2919 the reinsert happened right away and not lose any signals.
2921 Making this stack would also shrink the window in which breakpoints are
2922 uninserted (see comment in linux_wait_for_lwp) but not enough for
2923 complete correctness, so it won't solve that problem. It may be
2924 worthwhile just to solve this one, however. */
2925 if (lwp
->bp_reinsert
!= 0)
2928 fprintf (stderr
, " pending reinsert at 0x%s\n",
2929 paddress (lwp
->bp_reinsert
));
2931 if (lwp
->bp_reinsert
!= 0 && can_hardware_single_step ())
2933 if (fast_tp_collecting
== 0)
2936 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
2938 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
2945 /* Postpone any pending signal. It was enqueued above. */
2949 if (fast_tp_collecting
== 1)
2953 lwp %ld wants to get out of fast tracepoint jump pad (exit-jump-pad-bkpt)\n",
2956 /* Postpone any pending signal. It was enqueued above. */
2959 else if (fast_tp_collecting
== 2)
2963 lwp %ld wants to get out of fast tracepoint jump pad single-stepping\n",
2966 if (can_hardware_single_step ())
2969 fatal ("moving out of jump pad single-stepping"
2970 " not implemented on this target");
2972 /* Postpone any pending signal. It was enqueued above. */
2976 /* If we have while-stepping actions in this thread set it stepping.
2977 If we have a signal to deliver, it may or may not be set to
2978 SIG_IGN, we don't know. Assume so, and allow collecting
2979 while-stepping into a signal handler. A possible smart thing to
2980 do would be to set an internal breakpoint at the signal return
2981 address, continue, and carry on catching this while-stepping
2982 action only when that breakpoint is hit. A future
2984 if (get_lwp_thread (lwp
)->while_stepping
!= NULL
2985 && can_hardware_single_step ())
2989 "lwp %ld has a while-stepping action -> forcing step.\n",
2994 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
2996 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
2997 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
2998 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
3001 /* If we have pending signals, consume one unless we are trying to
3002 reinsert a breakpoint or we're trying to finish a fast tracepoint
3004 if (lwp
->pending_signals
!= NULL
3005 && lwp
->bp_reinsert
== 0
3006 && fast_tp_collecting
== 0)
3008 struct pending_signals
**p_sig
;
3010 p_sig
= &lwp
->pending_signals
;
3011 while ((*p_sig
)->prev
!= NULL
)
3012 p_sig
= &(*p_sig
)->prev
;
3014 signal
= (*p_sig
)->signal
;
3015 if ((*p_sig
)->info
.si_signo
!= 0)
3016 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
3022 if (the_low_target
.prepare_to_resume
!= NULL
)
3023 the_low_target
.prepare_to_resume (lwp
);
3025 regcache_invalidate_one ((struct inferior_list_entry
*)
3026 get_lwp_thread (lwp
));
3029 lwp
->stopped_by_watchpoint
= 0;
3030 lwp
->stepping
= step
;
3031 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0,
3032 /* Coerce to a uintptr_t first to avoid potential gcc warning
3033 of coercing an 8 byte integer to a 4 byte pointer. */
3034 (PTRACE_ARG4_TYPE
) (uintptr_t) signal
);
3036 current_inferior
= saved_inferior
;
3039 /* ESRCH from ptrace either means that the thread was already
3040 running (an error) or that it is gone (a race condition). If
3041 it's gone, we will get a notification the next time we wait,
3042 so we can ignore the error. We could differentiate these
3043 two, but it's tricky without waiting; the thread still exists
3044 as a zombie, so sending it signal 0 would succeed. So just
3049 perror_with_name ("ptrace");
3053 struct thread_resume_array
3055 struct thread_resume
*resume
;
3059 /* This function is called once per thread. We look up the thread
3060 in RESUME_PTR, and mark the thread with a pointer to the appropriate
3063 This algorithm is O(threads * resume elements), but resume elements
3064 is small (and will remain small at least until GDB supports thread
3067 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3069 struct lwp_info
*lwp
;
3070 struct thread_info
*thread
;
3072 struct thread_resume_array
*r
;
3074 thread
= (struct thread_info
*) entry
;
3075 lwp
= get_thread_lwp (thread
);
3078 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3080 ptid_t ptid
= r
->resume
[ndx
].thread
;
3081 if (ptid_equal (ptid
, minus_one_ptid
)
3082 || ptid_equal (ptid
, entry
->id
)
3083 || (ptid_is_pid (ptid
)
3084 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
3085 || (ptid_get_lwp (ptid
) == -1
3086 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
3088 if (r
->resume
[ndx
].kind
== resume_stop
3089 && thread
->last_resume_kind
== resume_stop
)
3092 fprintf (stderr
, "already %s LWP %ld at GDB's request\n",
3093 thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
3101 lwp
->resume
= &r
->resume
[ndx
];
3102 thread
->last_resume_kind
= lwp
->resume
->kind
;
3104 /* If we had a deferred signal to report, dequeue one now.
3105 This can happen if LWP gets more than one signal while
3106 trying to get out of a jump pad. */
3108 && !lwp
->status_pending_p
3109 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3111 lwp
->status_pending_p
= 1;
3115 "Dequeueing deferred signal %d for LWP %ld, "
3116 "leaving status pending.\n",
3117 WSTOPSIG (lwp
->status_pending
), lwpid_of (lwp
));
3124 /* No resume action for this thread. */
3131 /* Set *FLAG_P if this lwp has an interesting status pending. */
3133 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3135 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3137 /* LWPs which will not be resumed are not interesting, because
3138 we might not wait for them next time through linux_wait. */
3139 if (lwp
->resume
== NULL
)
3142 if (lwp
->status_pending_p
)
3143 * (int *) flag_p
= 1;
3148 /* Return 1 if this lwp that GDB wants running is stopped at an
3149 internal breakpoint that we need to step over. It assumes that any
3150 required STOP_PC adjustment has already been propagated to the
3151 inferior's regcache. */
3154 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3156 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3157 struct thread_info
*thread
;
3158 struct thread_info
*saved_inferior
;
3161 /* LWPs which will not be resumed are not interesting, because we
3162 might not wait for them next time through linux_wait. */
3168 "Need step over [LWP %ld]? Ignoring, not stopped\n",
3173 thread
= get_lwp_thread (lwp
);
3175 if (thread
->last_resume_kind
== resume_stop
)
3179 "Need step over [LWP %ld]? Ignoring, should remain stopped\n",
3184 gdb_assert (lwp
->suspended
>= 0);
3190 "Need step over [LWP %ld]? Ignoring, suspended\n",
3195 if (!lwp
->need_step_over
)
3199 "Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
3202 if (lwp
->status_pending_p
)
3206 "Need step over [LWP %ld]? Ignoring, has pending status.\n",
3211 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3215 /* If the PC has changed since we stopped, then don't do anything,
3216 and let the breakpoint/tracepoint be hit. This happens if, for
3217 instance, GDB handled the decr_pc_after_break subtraction itself,
3218 GDB is OOL stepping this thread, or the user has issued a "jump"
3219 command, or poked thread's registers herself. */
3220 if (pc
!= lwp
->stop_pc
)
3224 "Need step over [LWP %ld]? Cancelling, PC was changed. "
3225 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3226 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
3228 lwp
->need_step_over
= 0;
3232 saved_inferior
= current_inferior
;
3233 current_inferior
= thread
;
3235 /* We can only step over breakpoints we know about. */
3236 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3238 /* Don't step over a breakpoint that GDB expects to hit
3240 if (gdb_breakpoint_here (pc
))
3244 "Need step over [LWP %ld]? yes, but found"
3245 " GDB breakpoint at 0x%s; skipping step over\n",
3246 lwpid_of (lwp
), paddress (pc
));
3248 current_inferior
= saved_inferior
;
3255 "Need step over [LWP %ld]? yes, "
3256 "found breakpoint at 0x%s\n",
3257 lwpid_of (lwp
), paddress (pc
));
3259 /* We've found an lwp that needs stepping over --- return 1 so
3260 that find_inferior stops looking. */
3261 current_inferior
= saved_inferior
;
3263 /* If the step over is cancelled, this is set again. */
3264 lwp
->need_step_over
= 0;
3269 current_inferior
= saved_inferior
;
3273 "Need step over [LWP %ld]? No, no breakpoint found at 0x%s\n",
3274 lwpid_of (lwp
), paddress (pc
));
3279 /* Start a step-over operation on LWP. When LWP stopped at a
3280 breakpoint, to make progress, we need to remove the breakpoint out
3281 of the way. If we let other threads run while we do that, they may
3282 pass by the breakpoint location and miss hitting it. To avoid
3283 that, a step-over momentarily stops all threads while LWP is
3284 single-stepped while the breakpoint is temporarily uninserted from
3285 the inferior. When the single-step finishes, we reinsert the
3286 breakpoint, and let all threads that are supposed to be running,
3289 On targets that don't support hardware single-step, we don't
3290 currently support full software single-stepping. Instead, we only
3291 support stepping over the thread event breakpoint, by asking the
3292 low target where to place a reinsert breakpoint. Since this
3293 routine assumes the breakpoint being stepped over is a thread event
3294 breakpoint, it usually assumes the return address of the current
3295 function is a good enough place to set the reinsert breakpoint. */
3298 start_step_over (struct lwp_info
*lwp
)
3300 struct thread_info
*saved_inferior
;
3306 "Starting step-over on LWP %ld. Stopping all threads\n",
3309 stop_all_lwps (1, lwp
);
3310 gdb_assert (lwp
->suspended
== 0);
3313 fprintf (stderr
, "Done stopping all threads for step-over.\n");
3315 /* Note, we should always reach here with an already adjusted PC,
3316 either by GDB (if we're resuming due to GDB's request), or by our
3317 caller, if we just finished handling an internal breakpoint GDB
3318 shouldn't care about. */
3321 saved_inferior
= current_inferior
;
3322 current_inferior
= get_lwp_thread (lwp
);
3324 lwp
->bp_reinsert
= pc
;
3325 uninsert_breakpoints_at (pc
);
3326 uninsert_fast_tracepoint_jumps_at (pc
);
3328 if (can_hardware_single_step ())
3334 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3335 set_reinsert_breakpoint (raddr
);
3339 current_inferior
= saved_inferior
;
3341 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3343 /* Require next event from this LWP. */
3344 step_over_bkpt
= lwp
->head
.id
;
3348 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3349 start_step_over, if still there, and delete any reinsert
3350 breakpoints we've set, on non hardware single-step targets. */
3353 finish_step_over (struct lwp_info
*lwp
)
3355 if (lwp
->bp_reinsert
!= 0)
3358 fprintf (stderr
, "Finished step over.\n");
3360 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3361 may be no breakpoint to reinsert there by now. */
3362 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3363 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3365 lwp
->bp_reinsert
= 0;
3367 /* Delete any software-single-step reinsert breakpoints. No
3368 longer needed. We don't have to worry about other threads
3369 hitting this trap, and later not being able to explain it,
3370 because we were stepping over a breakpoint, and we hold all
3371 threads but LWP stopped while doing that. */
3372 if (!can_hardware_single_step ())
3373 delete_reinsert_breakpoints ();
3375 step_over_bkpt
= null_ptid
;
3382 /* This function is called once per thread. We check the thread's resume
3383 request, which will tell us whether to resume, step, or leave the thread
3384 stopped; and what signal, if any, it should be sent.
3386 For threads which we aren't explicitly told otherwise, we preserve
3387 the stepping flag; this is used for stepping over gdbserver-placed
3390 If pending_flags was set in any thread, we queue any needed
3391 signals, since we won't actually resume. We already have a pending
3392 event to report, so we don't need to preserve any step requests;
3393 they should be re-issued if necessary. */
3396 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3398 struct lwp_info
*lwp
;
3399 struct thread_info
*thread
;
3401 int leave_all_stopped
= * (int *) arg
;
3404 thread
= (struct thread_info
*) entry
;
3405 lwp
= get_thread_lwp (thread
);
3407 if (lwp
->resume
== NULL
)
3410 if (lwp
->resume
->kind
== resume_stop
)
3413 fprintf (stderr
, "resume_stop request for LWP %ld\n", lwpid_of (lwp
));
3418 fprintf (stderr
, "stopping LWP %ld\n", lwpid_of (lwp
));
3420 /* Stop the thread, and wait for the event asynchronously,
3421 through the event loop. */
3427 fprintf (stderr
, "already stopped LWP %ld\n",
3430 /* The LWP may have been stopped in an internal event that
3431 was not meant to be notified back to GDB (e.g., gdbserver
3432 breakpoint), so we should be reporting a stop event in
3435 /* If the thread already has a pending SIGSTOP, this is a
3436 no-op. Otherwise, something later will presumably resume
3437 the thread and this will cause it to cancel any pending
3438 operation, due to last_resume_kind == resume_stop. If
3439 the thread already has a pending status to report, we
3440 will still report it the next time we wait - see
3441 status_pending_p_callback. */
3443 /* If we already have a pending signal to report, then
3444 there's no need to queue a SIGSTOP, as this means we're
3445 midway through moving the LWP out of the jumppad, and we
3446 will report the pending signal as soon as that is
3448 if (lwp
->pending_signals_to_report
== NULL
)
3452 /* For stop requests, we're done. */
3454 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3458 /* If this thread which is about to be resumed has a pending status,
3459 then don't resume any threads - we can just report the pending
3460 status. Make sure to queue any signals that would otherwise be
3461 sent. In all-stop mode, we do this decision based on if *any*
3462 thread has a pending status. If there's a thread that needs the
3463 step-over-breakpoint dance, then don't resume any other thread
3464 but that particular one. */
3465 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
3470 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
3472 step
= (lwp
->resume
->kind
== resume_step
);
3473 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
3478 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
3480 /* If we have a new signal, enqueue the signal. */
3481 if (lwp
->resume
->sig
!= 0)
3483 struct pending_signals
*p_sig
;
3484 p_sig
= xmalloc (sizeof (*p_sig
));
3485 p_sig
->prev
= lwp
->pending_signals
;
3486 p_sig
->signal
= lwp
->resume
->sig
;
3487 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3489 /* If this is the same signal we were previously stopped by,
3490 make sure to queue its siginfo. We can ignore the return
3491 value of ptrace; if it fails, we'll skip
3492 PTRACE_SETSIGINFO. */
3493 if (WIFSTOPPED (lwp
->last_status
)
3494 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
3495 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
3497 lwp
->pending_signals
= p_sig
;
3501 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3507 linux_resume (struct thread_resume
*resume_info
, size_t n
)
3509 struct thread_resume_array array
= { resume_info
, n
};
3510 struct lwp_info
*need_step_over
= NULL
;
3512 int leave_all_stopped
;
3514 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
3516 /* If there is a thread which would otherwise be resumed, which has
3517 a pending status, then don't resume any threads - we can just
3518 report the pending status. Make sure to queue any signals that
3519 would otherwise be sent. In non-stop mode, we'll apply this
3520 logic to each thread individually. We consume all pending events
3521 before considering to start a step-over (in all-stop). */
3524 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
3526 /* If there is a thread which would otherwise be resumed, which is
3527 stopped at a breakpoint that needs stepping over, then don't
3528 resume any threads - have it step over the breakpoint with all
3529 other threads stopped, then resume all threads again. Make sure
3530 to queue any signals that would otherwise be delivered or
3532 if (!any_pending
&& supports_breakpoints ())
3534 = (struct lwp_info
*) find_inferior (&all_lwps
,
3535 need_step_over_p
, NULL
);
3537 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
3541 if (need_step_over
!= NULL
)
3542 fprintf (stderr
, "Not resuming all, need step over\n");
3543 else if (any_pending
)
3545 "Not resuming, all-stop and found "
3546 "an LWP with pending status\n");
3548 fprintf (stderr
, "Resuming, no pending status or step over needed\n");
3551 /* Even if we're leaving threads stopped, queue all signals we'd
3552 otherwise deliver. */
3553 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
3556 start_step_over (need_step_over
);
3559 /* This function is called once per thread. We check the thread's
3560 last resume request, which will tell us whether to resume, step, or
3561 leave the thread stopped. Any signal the client requested to be
3562 delivered has already been enqueued at this point.
3564 If any thread that GDB wants running is stopped at an internal
3565 breakpoint that needs stepping over, we start a step-over operation
3566 on that particular thread, and leave all others stopped. */
3569 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3571 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3572 struct thread_info
*thread
;
3580 "proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
3585 fprintf (stderr
, " LWP %ld already running\n", lwpid_of (lwp
));
3589 thread
= get_lwp_thread (lwp
);
3591 if (thread
->last_resume_kind
== resume_stop
3592 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
3595 fprintf (stderr
, " client wants LWP to remain %ld stopped\n",
3600 if (lwp
->status_pending_p
)
3603 fprintf (stderr
, " LWP %ld has pending status, leaving stopped\n",
3608 gdb_assert (lwp
->suspended
>= 0);
3613 fprintf (stderr
, " LWP %ld is suspended\n", lwpid_of (lwp
));
3617 if (thread
->last_resume_kind
== resume_stop
3618 && lwp
->pending_signals_to_report
== NULL
3619 && lwp
->collecting_fast_tracepoint
== 0)
3621 /* We haven't reported this LWP as stopped yet (otherwise, the
3622 last_status.kind check above would catch it, and we wouldn't
3623 reach here. This LWP may have been momentarily paused by a
3624 stop_all_lwps call while handling for example, another LWP's
3625 step-over. In that case, the pending expected SIGSTOP signal
3626 that was queued at vCont;t handling time will have already
3627 been consumed by wait_for_sigstop, and so we need to requeue
3628 another one here. Note that if the LWP already has a SIGSTOP
3629 pending, this is a no-op. */
3633 "Client wants LWP %ld to stop. "
3634 "Making sure it has a SIGSTOP pending\n",
3640 step
= thread
->last_resume_kind
== resume_step
;
3641 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3646 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3648 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3654 gdb_assert (lwp
->suspended
>= 0);
3656 return proceed_one_lwp (entry
, except
);
3659 /* When we finish a step-over, set threads running again. If there's
3660 another thread that may need a step-over, now's the time to start
3661 it. Eventually, we'll move all threads past their breakpoints. */
3664 proceed_all_lwps (void)
3666 struct lwp_info
*need_step_over
;
3668 /* If there is a thread which would otherwise be resumed, which is
3669 stopped at a breakpoint that needs stepping over, then don't
3670 resume any threads - have it step over the breakpoint with all
3671 other threads stopped, then resume all threads again. */
3673 if (supports_breakpoints ())
3676 = (struct lwp_info
*) find_inferior (&all_lwps
,
3677 need_step_over_p
, NULL
);
3679 if (need_step_over
!= NULL
)
3682 fprintf (stderr
, "proceed_all_lwps: found "
3683 "thread %ld needing a step-over\n",
3684 lwpid_of (need_step_over
));
3686 start_step_over (need_step_over
);
3692 fprintf (stderr
, "Proceeding, no step-over needed\n");
3694 find_inferior (&all_lwps
, proceed_one_lwp
, NULL
);
3697 /* Stopped LWPs that the client wanted to be running, that don't have
3698 pending statuses, are set to run again, except for EXCEPT, if not
3699 NULL. This undoes a stop_all_lwps call. */
3702 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
3708 "unstopping all lwps, except=(LWP %ld)\n", lwpid_of (except
));
3711 "unstopping all lwps\n");
3715 find_inferior (&all_lwps
, unsuspend_and_proceed_one_lwp
, except
);
3717 find_inferior (&all_lwps
, proceed_one_lwp
, except
);
3720 #ifdef HAVE_LINUX_USRREGS
3723 register_addr (int regnum
)
3727 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
3728 error ("Invalid register number %d.", regnum
);
3730 addr
= the_low_target
.regmap
[regnum
];
3735 /* Fetch one register. */
3737 fetch_register (struct regcache
*regcache
, int regno
)
3744 if (regno
>= the_low_target
.num_regs
)
3746 if ((*the_low_target
.cannot_fetch_register
) (regno
))
3749 regaddr
= register_addr (regno
);
3753 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
3754 & -sizeof (PTRACE_XFER_TYPE
));
3755 buf
= alloca (size
);
3757 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3758 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
3761 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
3762 ptrace (PTRACE_PEEKUSER
, pid
,
3763 /* Coerce to a uintptr_t first to avoid potential gcc warning
3764 of coercing an 8 byte integer to a 4 byte pointer. */
3765 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
, 0);
3766 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
3768 error ("reading register %d: %s", regno
, strerror (errno
));
3771 if (the_low_target
.supply_ptrace_register
)
3772 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
3774 supply_register (regcache
, regno
, buf
);
3777 /* Store one register. */
3779 store_register (struct regcache
*regcache
, int regno
)
3786 if (regno
>= the_low_target
.num_regs
)
3788 if ((*the_low_target
.cannot_store_register
) (regno
))
3791 regaddr
= register_addr (regno
);
3795 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
3796 & -sizeof (PTRACE_XFER_TYPE
));
3797 buf
= alloca (size
);
3798 memset (buf
, 0, size
);
3800 if (the_low_target
.collect_ptrace_register
)
3801 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
3803 collect_register (regcache
, regno
, buf
);
3805 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3806 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
3809 ptrace (PTRACE_POKEUSER
, pid
,
3810 /* Coerce to a uintptr_t first to avoid potential gcc warning
3811 about coercing an 8 byte integer to a 4 byte pointer. */
3812 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
,
3813 (PTRACE_ARG4_TYPE
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
3816 /* At this point, ESRCH should mean the process is
3817 already gone, in which case we simply ignore attempts
3818 to change its registers. See also the related
3819 comment in linux_resume_one_lwp. */
3823 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
3824 error ("writing register %d: %s", regno
, strerror (errno
));
3826 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
3830 /* Fetch all registers, or just one, from the child process. */
3832 usr_fetch_inferior_registers (struct regcache
*regcache
, int regno
)
3835 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
3836 fetch_register (regcache
, regno
);
3838 fetch_register (regcache
, regno
);
3841 /* Store our register values back into the inferior.
3842 If REGNO is -1, do this for all registers.
3843 Otherwise, REGNO specifies which register (so we can save time). */
3845 usr_store_inferior_registers (struct regcache
*regcache
, int regno
)
3848 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
3849 store_register (regcache
, regno
);
3851 store_register (regcache
, regno
);
3853 #endif /* HAVE_LINUX_USRREGS */
3857 #ifdef HAVE_LINUX_REGSETS
3860 regsets_fetch_inferior_registers (struct regcache
*regcache
)
3862 struct regset_info
*regset
;
3863 int saw_general_regs
= 0;
3867 regset
= target_regsets
;
3869 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3870 while (regset
->size
>= 0)
3875 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
3881 buf
= xmalloc (regset
->size
);
3883 nt_type
= regset
->nt_type
;
3887 iov
.iov_len
= regset
->size
;
3888 data
= (void *) &iov
;
3894 res
= ptrace (regset
->get_request
, pid
, nt_type
, data
);
3896 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
3902 /* If we get EIO on a regset, do not try it again for
3904 disabled_regsets
[regset
- target_regsets
] = 1;
3911 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
3916 else if (regset
->type
== GENERAL_REGS
)
3917 saw_general_regs
= 1;
3918 regset
->store_function (regcache
, buf
);
3922 if (saw_general_regs
)
3929 regsets_store_inferior_registers (struct regcache
*regcache
)
3931 struct regset_info
*regset
;
3932 int saw_general_regs
= 0;
3936 regset
= target_regsets
;
3938 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3939 while (regset
->size
>= 0)
3944 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
3950 buf
= xmalloc (regset
->size
);
3952 /* First fill the buffer with the current register set contents,
3953 in case there are any items in the kernel's regset that are
3954 not in gdbserver's regcache. */
3956 nt_type
= regset
->nt_type
;
3960 iov
.iov_len
= regset
->size
;
3961 data
= (void *) &iov
;
3967 res
= ptrace (regset
->get_request
, pid
, nt_type
, data
);
3969 res
= ptrace (regset
->get_request
, pid
, &iov
, data
);
3974 /* Then overlay our cached registers on that. */
3975 regset
->fill_function (regcache
, buf
);
3977 /* Only now do we write the register set. */
3979 res
= ptrace (regset
->set_request
, pid
, nt_type
, data
);
3981 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
3989 /* If we get EIO on a regset, do not try it again for
3991 disabled_regsets
[regset
- target_regsets
] = 1;
3995 else if (errno
== ESRCH
)
3997 /* At this point, ESRCH should mean the process is
3998 already gone, in which case we simply ignore attempts
3999 to change its registers. See also the related
4000 comment in linux_resume_one_lwp. */
4006 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4009 else if (regset
->type
== GENERAL_REGS
)
4010 saw_general_regs
= 1;
4014 if (saw_general_regs
)
4021 #endif /* HAVE_LINUX_REGSETS */
4025 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4027 #ifdef HAVE_LINUX_REGSETS
4028 if (regsets_fetch_inferior_registers (regcache
) == 0)
4031 #ifdef HAVE_LINUX_USRREGS
4032 usr_fetch_inferior_registers (regcache
, regno
);
4037 linux_store_registers (struct regcache
*regcache
, int regno
)
4039 #ifdef HAVE_LINUX_REGSETS
4040 if (regsets_store_inferior_registers (regcache
) == 0)
4043 #ifdef HAVE_LINUX_USRREGS
4044 usr_store_inferior_registers (regcache
, regno
);
4049 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4050 to debugger memory starting at MYADDR. */
4053 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4056 /* Round starting address down to longword boundary. */
4057 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4058 /* Round ending address up; get number of longwords that makes. */
4060 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4061 / sizeof (PTRACE_XFER_TYPE
);
4062 /* Allocate buffer of that many longwords. */
4063 register PTRACE_XFER_TYPE
*buffer
4064 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4067 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4069 /* Try using /proc. Don't bother for one word. */
4070 if (len
>= 3 * sizeof (long))
4072 /* We could keep this file open and cache it - possibly one per
4073 thread. That requires some juggling, but is even faster. */
4074 sprintf (filename
, "/proc/%d/mem", pid
);
4075 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4079 /* If pread64 is available, use it. It's faster if the kernel
4080 supports it (only one syscall), and it's 64-bit safe even on
4081 32-bit platforms (for instance, SPARC debugging a SPARC64
4084 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
4086 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, myaddr
, len
) != len
)
4098 /* Read all the longwords */
4099 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4102 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4103 about coercing an 8 byte integer to a 4 byte pointer. */
4104 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4105 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4110 /* Copy appropriate bytes out of the buffer. */
4112 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4118 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4119 memory at MEMADDR. On failure (cannot write to the inferior)
4120 returns the value of errno. */
4123 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4126 /* Round starting address down to longword boundary. */
4127 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4128 /* Round ending address up; get number of longwords that makes. */
4130 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4131 / sizeof (PTRACE_XFER_TYPE
);
4133 /* Allocate buffer of that many longwords. */
4134 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4135 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4137 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4141 /* Dump up to four bytes. */
4142 unsigned int val
= * (unsigned int *) myaddr
;
4148 val
= val
& 0xffffff;
4149 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4150 val
, (long)memaddr
);
4153 /* Fill start and end extra bytes of buffer with existing memory data. */
4156 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4157 about coercing an 8 byte integer to a 4 byte pointer. */
4158 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4159 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4167 = ptrace (PTRACE_PEEKTEXT
, pid
,
4168 /* Coerce to a uintptr_t first to avoid potential gcc warning
4169 about coercing an 8 byte integer to a 4 byte pointer. */
4170 (PTRACE_ARG3_TYPE
) (uintptr_t) (addr
+ (count
- 1)
4171 * sizeof (PTRACE_XFER_TYPE
)),
4177 /* Copy data to be written over corresponding part of buffer. */
4179 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4182 /* Write the entire buffer. */
4184 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4187 ptrace (PTRACE_POKETEXT
, pid
,
4188 /* Coerce to a uintptr_t first to avoid potential gcc warning
4189 about coercing an 8 byte integer to a 4 byte pointer. */
4190 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
4191 (PTRACE_ARG4_TYPE
) buffer
[i
]);
4199 /* Non-zero if the kernel supports PTRACE_O_TRACEFORK. */
4200 static int linux_supports_tracefork_flag
;
4203 linux_enable_event_reporting (int pid
)
4205 if (!linux_supports_tracefork_flag
)
4208 ptrace (PTRACE_SETOPTIONS
, pid
, 0, (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
4211 /* Helper functions for linux_test_for_tracefork, called via clone (). */
4214 linux_tracefork_grandchild (void *arg
)
4219 #define STACK_SIZE 4096
4222 linux_tracefork_child (void *arg
)
4224 ptrace (PTRACE_TRACEME
, 0, 0, 0);
4225 kill (getpid (), SIGSTOP
);
4227 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4230 linux_tracefork_grandchild (NULL
);
4232 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4235 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
4236 CLONE_VM
| SIGCHLD
, NULL
);
4238 clone (linux_tracefork_grandchild
, (char *) arg
+ STACK_SIZE
,
4239 CLONE_VM
| SIGCHLD
, NULL
);
4242 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4247 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
4248 sure that we can enable the option, and that it had the desired
4252 linux_test_for_tracefork (void)
4254 int child_pid
, ret
, status
;
4256 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4257 char *stack
= xmalloc (STACK_SIZE
* 4);
4258 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4260 linux_supports_tracefork_flag
= 0;
4262 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4264 child_pid
= fork ();
4266 linux_tracefork_child (NULL
);
4268 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4270 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
4272 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
4273 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4274 #else /* !__ia64__ */
4275 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
4276 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4277 #endif /* !__ia64__ */
4279 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4281 if (child_pid
== -1)
4282 perror_with_name ("clone");
4284 ret
= my_waitpid (child_pid
, &status
, 0);
4286 perror_with_name ("waitpid");
4287 else if (ret
!= child_pid
)
4288 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
4289 if (! WIFSTOPPED (status
))
4290 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
4292 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
4293 (PTRACE_ARG4_TYPE
) PTRACE_O_TRACEFORK
);
4296 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4299 warning ("linux_test_for_tracefork: failed to kill child");
4303 ret
= my_waitpid (child_pid
, &status
, 0);
4304 if (ret
!= child_pid
)
4305 warning ("linux_test_for_tracefork: failed to wait for killed child");
4306 else if (!WIFSIGNALED (status
))
4307 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
4308 "killed child", status
);
4313 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
4315 warning ("linux_test_for_tracefork: failed to resume child");
4317 ret
= my_waitpid (child_pid
, &status
, 0);
4319 if (ret
== child_pid
&& WIFSTOPPED (status
)
4320 && status
>> 16 == PTRACE_EVENT_FORK
)
4323 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
4324 if (ret
== 0 && second_pid
!= 0)
4328 linux_supports_tracefork_flag
= 1;
4329 my_waitpid (second_pid
, &second_status
, 0);
4330 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
4332 warning ("linux_test_for_tracefork: failed to kill second child");
4333 my_waitpid (second_pid
, &status
, 0);
4337 warning ("linux_test_for_tracefork: unexpected result from waitpid "
4338 "(%d, status 0x%x)", ret
, status
);
4342 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4344 warning ("linux_test_for_tracefork: failed to kill child");
4345 my_waitpid (child_pid
, &status
, 0);
4347 while (WIFSTOPPED (status
));
4349 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4351 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4356 linux_look_up_symbols (void)
4358 #ifdef USE_THREAD_DB
4359 struct process_info
*proc
= current_process ();
4361 if (proc
->private->thread_db
!= NULL
)
4364 /* If the kernel supports tracing forks then it also supports tracing
4365 clones, and then we don't need to use the magic thread event breakpoint
4366 to learn about threads. */
4367 thread_db_init (!linux_supports_tracefork_flag
);
4372 linux_request_interrupt (void)
4374 extern unsigned long signal_pid
;
4376 if (!ptid_equal (cont_thread
, null_ptid
)
4377 && !ptid_equal (cont_thread
, minus_one_ptid
))
4379 struct lwp_info
*lwp
;
4382 lwp
= get_thread_lwp (current_inferior
);
4383 lwpid
= lwpid_of (lwp
);
4384 kill_lwp (lwpid
, SIGINT
);
4387 kill_lwp (signal_pid
, SIGINT
);
4390 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4391 to debugger memory starting at MYADDR. */
4394 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4396 char filename
[PATH_MAX
];
4398 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4400 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4402 fd
= open (filename
, O_RDONLY
);
4406 if (offset
!= (CORE_ADDR
) 0
4407 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4410 n
= read (fd
, myaddr
, len
);
4417 /* These breakpoint and watchpoint related wrapper functions simply
4418 pass on the function call if the target has registered a
4419 corresponding function. */
4422 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
4424 if (the_low_target
.insert_point
!= NULL
)
4425 return the_low_target
.insert_point (type
, addr
, len
);
4427 /* Unsupported (see target.h). */
4432 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
4434 if (the_low_target
.remove_point
!= NULL
)
4435 return the_low_target
.remove_point (type
, addr
, len
);
4437 /* Unsupported (see target.h). */
4442 linux_stopped_by_watchpoint (void)
4444 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4446 return lwp
->stopped_by_watchpoint
;
4450 linux_stopped_data_address (void)
4452 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4454 return lwp
->stopped_data_address
;
4457 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4458 #if defined(__mcoldfire__)
4459 /* These should really be defined in the kernel's ptrace.h header. */
4460 #define PT_TEXT_ADDR 49*4
4461 #define PT_DATA_ADDR 50*4
4462 #define PT_TEXT_END_ADDR 51*4
4464 #define PT_TEXT_ADDR 220
4465 #define PT_TEXT_END_ADDR 224
4466 #define PT_DATA_ADDR 228
4467 #elif defined(__TMS320C6X__)
4468 #define PT_TEXT_ADDR (0x10000*4)
4469 #define PT_DATA_ADDR (0x10004*4)
4470 #define PT_TEXT_END_ADDR (0x10008*4)
4473 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4474 to tell gdb about. */
4477 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
4479 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
4480 unsigned long text
, text_end
, data
;
4481 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4485 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
4486 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
4487 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
4491 /* Both text and data offsets produced at compile-time (and so
4492 used by gdb) are relative to the beginning of the program,
4493 with the data segment immediately following the text segment.
4494 However, the actual runtime layout in memory may put the data
4495 somewhere else, so when we send gdb a data base-address, we
4496 use the real data base address and subtract the compile-time
4497 data base-address from it (which is just the length of the
4498 text segment). BSS immediately follows data in both
4501 *data_p
= data
- (text_end
- text
);
4511 linux_qxfer_osdata (const char *annex
,
4512 unsigned char *readbuf
, unsigned const char *writebuf
,
4513 CORE_ADDR offset
, int len
)
4515 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
4518 /* Convert a native/host siginfo object, into/from the siginfo in the
4519 layout of the inferiors' architecture. */
4522 siginfo_fixup (struct siginfo
*siginfo
, void *inf_siginfo
, int direction
)
4526 if (the_low_target
.siginfo_fixup
!= NULL
)
4527 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4529 /* If there was no callback, or the callback didn't do anything,
4530 then just do a straight memcpy. */
4534 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
4536 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
4541 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
4542 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
4545 struct siginfo siginfo
;
4546 char inf_siginfo
[sizeof (struct siginfo
)];
4548 if (current_inferior
== NULL
)
4551 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4554 fprintf (stderr
, "%s siginfo for lwp %d.\n",
4555 readbuf
!= NULL
? "Reading" : "Writing",
4558 if (offset
>= sizeof (siginfo
))
4561 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
4564 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4565 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4566 inferior with a 64-bit GDBSERVER should look the same as debugging it
4567 with a 32-bit GDBSERVER, we need to convert it. */
4568 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4570 if (offset
+ len
> sizeof (siginfo
))
4571 len
= sizeof (siginfo
) - offset
;
4573 if (readbuf
!= NULL
)
4574 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4577 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4579 /* Convert back to ptrace layout before flushing it out. */
4580 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4582 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
4589 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4590 so we notice when children change state; as the handler for the
4591 sigsuspend in my_waitpid. */
4594 sigchld_handler (int signo
)
4596 int old_errno
= errno
;
4602 /* fprintf is not async-signal-safe, so call write
4604 if (write (2, "sigchld_handler\n",
4605 sizeof ("sigchld_handler\n") - 1) < 0)
4606 break; /* just ignore */
4610 if (target_is_async_p ())
4611 async_file_mark (); /* trigger a linux_wait */
4617 linux_supports_non_stop (void)
4623 linux_async (int enable
)
4625 int previous
= (linux_event_pipe
[0] != -1);
4628 fprintf (stderr
, "linux_async (%d), previous=%d\n",
4631 if (previous
!= enable
)
4634 sigemptyset (&mask
);
4635 sigaddset (&mask
, SIGCHLD
);
4637 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
4641 if (pipe (linux_event_pipe
) == -1)
4642 fatal ("creating event pipe failed.");
4644 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
4645 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
4647 /* Register the event loop handler. */
4648 add_file_handler (linux_event_pipe
[0],
4649 handle_target_event
, NULL
);
4651 /* Always trigger a linux_wait. */
4656 delete_file_handler (linux_event_pipe
[0]);
4658 close (linux_event_pipe
[0]);
4659 close (linux_event_pipe
[1]);
4660 linux_event_pipe
[0] = -1;
4661 linux_event_pipe
[1] = -1;
4664 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
4671 linux_start_non_stop (int nonstop
)
4673 /* Register or unregister from event-loop accordingly. */
4674 linux_async (nonstop
);
4679 linux_supports_multi_process (void)
4685 linux_supports_disable_randomization (void)
4687 #ifdef HAVE_PERSONALITY
4694 /* Enumerate spufs IDs for process PID. */
4696 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
4702 struct dirent
*entry
;
4704 sprintf (path
, "/proc/%ld/fd", pid
);
4705 dir
= opendir (path
);
4710 while ((entry
= readdir (dir
)) != NULL
)
4716 fd
= atoi (entry
->d_name
);
4720 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
4721 if (stat (path
, &st
) != 0)
4723 if (!S_ISDIR (st
.st_mode
))
4726 if (statfs (path
, &stfs
) != 0)
4728 if (stfs
.f_type
!= SPUFS_MAGIC
)
4731 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
4733 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
4743 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
4744 object type, using the /proc file system. */
4746 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
4747 unsigned const char *writebuf
,
4748 CORE_ADDR offset
, int len
)
4750 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
4755 if (!writebuf
&& !readbuf
)
4763 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
4766 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
4767 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
4772 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4779 ret
= write (fd
, writebuf
, (size_t) len
);
4781 ret
= read (fd
, readbuf
, (size_t) len
);
4787 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
4788 struct target_loadseg
4790 /* Core address to which the segment is mapped. */
4792 /* VMA recorded in the program header. */
4794 /* Size of this segment in memory. */
4798 # if defined PT_GETDSBT
4799 struct target_loadmap
4801 /* Protocol version number, must be zero. */
4803 /* Pointer to the DSBT table, its size, and the DSBT index. */
4804 unsigned *dsbt_table
;
4805 unsigned dsbt_size
, dsbt_index
;
4806 /* Number of segments in this map. */
4808 /* The actual memory map. */
4809 struct target_loadseg segs
[/*nsegs*/];
4811 # define LINUX_LOADMAP PT_GETDSBT
4812 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
4813 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
4815 struct target_loadmap
4817 /* Protocol version number, must be zero. */
4819 /* Number of segments in this map. */
4821 /* The actual memory map. */
4822 struct target_loadseg segs
[/*nsegs*/];
4824 # define LINUX_LOADMAP PTRACE_GETFDPIC
4825 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
4826 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
4830 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
4831 unsigned char *myaddr
, unsigned int len
)
4833 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4835 struct target_loadmap
*data
= NULL
;
4836 unsigned int actual_length
, copy_length
;
4838 if (strcmp (annex
, "exec") == 0)
4839 addr
= (int) LINUX_LOADMAP_EXEC
;
4840 else if (strcmp (annex
, "interp") == 0)
4841 addr
= (int) LINUX_LOADMAP_INTERP
;
4845 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
4851 actual_length
= sizeof (struct target_loadmap
)
4852 + sizeof (struct target_loadseg
) * data
->nsegs
;
4854 if (offset
< 0 || offset
> actual_length
)
4857 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
4858 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
4862 # define linux_read_loadmap NULL
4863 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
4866 linux_process_qsupported (const char *query
)
4868 if (the_low_target
.process_qsupported
!= NULL
)
4869 the_low_target
.process_qsupported (query
);
4873 linux_supports_tracepoints (void)
4875 if (*the_low_target
.supports_tracepoints
== NULL
)
4878 return (*the_low_target
.supports_tracepoints
) ();
4882 linux_read_pc (struct regcache
*regcache
)
4884 if (the_low_target
.get_pc
== NULL
)
4887 return (*the_low_target
.get_pc
) (regcache
);
4891 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
4893 gdb_assert (the_low_target
.set_pc
!= NULL
);
4895 (*the_low_target
.set_pc
) (regcache
, pc
);
4899 linux_thread_stopped (struct thread_info
*thread
)
4901 return get_thread_lwp (thread
)->stopped
;
4904 /* This exposes stop-all-threads functionality to other modules. */
4907 linux_pause_all (int freeze
)
4909 stop_all_lwps (freeze
, NULL
);
4912 /* This exposes unstop-all-threads functionality to other gdbserver
4916 linux_unpause_all (int unfreeze
)
4918 unstop_all_lwps (unfreeze
, NULL
);
4922 linux_prepare_to_access_memory (void)
4924 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
4927 linux_pause_all (1);
4932 linux_done_accessing_memory (void)
4934 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
4937 linux_unpause_all (1);
4941 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
4942 CORE_ADDR collector
,
4945 CORE_ADDR
*jump_entry
,
4946 CORE_ADDR
*trampoline
,
4947 ULONGEST
*trampoline_size
,
4948 unsigned char *jjump_pad_insn
,
4949 ULONGEST
*jjump_pad_insn_size
,
4950 CORE_ADDR
*adjusted_insn_addr
,
4951 CORE_ADDR
*adjusted_insn_addr_end
,
4954 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
4955 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
4956 jump_entry
, trampoline
, trampoline_size
,
4957 jjump_pad_insn
, jjump_pad_insn_size
,
4958 adjusted_insn_addr
, adjusted_insn_addr_end
,
4962 static struct emit_ops
*
4963 linux_emit_ops (void)
4965 if (the_low_target
.emit_ops
!= NULL
)
4966 return (*the_low_target
.emit_ops
) ();
4972 linux_get_min_fast_tracepoint_insn_len (void)
4974 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
4977 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
4980 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
4981 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
4983 char filename
[PATH_MAX
];
4985 const int auxv_size
= is_elf64
4986 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
4987 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
4989 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4991 fd
= open (filename
, O_RDONLY
);
4997 while (read (fd
, buf
, auxv_size
) == auxv_size
4998 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5002 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5004 switch (aux
->a_type
)
5007 *phdr_memaddr
= aux
->a_un
.a_val
;
5010 *num_phdr
= aux
->a_un
.a_val
;
5016 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5018 switch (aux
->a_type
)
5021 *phdr_memaddr
= aux
->a_un
.a_val
;
5024 *num_phdr
= aux
->a_un
.a_val
;
5032 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5034 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5035 "phdr_memaddr = %ld, phdr_num = %d",
5036 (long) *phdr_memaddr
, *num_phdr
);
5043 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5046 get_dynamic (const int pid
, const int is_elf64
)
5048 CORE_ADDR phdr_memaddr
, relocation
;
5050 unsigned char *phdr_buf
;
5051 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5053 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5056 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5057 phdr_buf
= alloca (num_phdr
* phdr_size
);
5059 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5062 /* Compute relocation: it is expected to be 0 for "regular" executables,
5063 non-zero for PIE ones. */
5065 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5068 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5070 if (p
->p_type
== PT_PHDR
)
5071 relocation
= phdr_memaddr
- p
->p_vaddr
;
5075 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5077 if (p
->p_type
== PT_PHDR
)
5078 relocation
= phdr_memaddr
- p
->p_vaddr
;
5081 if (relocation
== -1)
5083 warning ("Unexpected missing PT_PHDR");
5087 for (i
= 0; i
< num_phdr
; i
++)
5091 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5093 if (p
->p_type
== PT_DYNAMIC
)
5094 return p
->p_vaddr
+ relocation
;
5098 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5100 if (p
->p_type
== PT_DYNAMIC
)
5101 return p
->p_vaddr
+ relocation
;
5108 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5109 can be 0 if the inferior does not yet have the library list initialized. */
5112 get_r_debug (const int pid
, const int is_elf64
)
5114 CORE_ADDR dynamic_memaddr
;
5115 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5116 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5118 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5119 if (dynamic_memaddr
== 0)
5120 return (CORE_ADDR
) -1;
5122 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5126 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5128 if (dyn
->d_tag
== DT_DEBUG
)
5129 return dyn
->d_un
.d_val
;
5131 if (dyn
->d_tag
== DT_NULL
)
5136 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5138 if (dyn
->d_tag
== DT_DEBUG
)
5139 return dyn
->d_un
.d_val
;
5141 if (dyn
->d_tag
== DT_NULL
)
5145 dynamic_memaddr
+= dyn_size
;
5148 return (CORE_ADDR
) -1;
5151 /* Read one pointer from MEMADDR in the inferior. */
5154 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5157 return linux_read_memory (memaddr
, (unsigned char *) ptr
, ptr_size
);
5160 struct link_map_offsets
5162 /* Offset and size of r_debug.r_version. */
5163 int r_version_offset
;
5165 /* Offset and size of r_debug.r_map. */
5168 /* Offset to l_addr field in struct link_map. */
5171 /* Offset to l_name field in struct link_map. */
5174 /* Offset to l_ld field in struct link_map. */
5177 /* Offset to l_next field in struct link_map. */
5180 /* Offset to l_prev field in struct link_map. */
5184 /* Construct qXfer:libraries:read reply. */
5187 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5188 unsigned const char *writebuf
,
5189 CORE_ADDR offset
, int len
)
5192 unsigned document_len
;
5193 struct process_info_private
*const priv
= current_process ()->private;
5194 char filename
[PATH_MAX
];
5197 static const struct link_map_offsets lmo_32bit_offsets
=
5199 0, /* r_version offset. */
5200 4, /* r_debug.r_map offset. */
5201 0, /* l_addr offset in link_map. */
5202 4, /* l_name offset in link_map. */
5203 8, /* l_ld offset in link_map. */
5204 12, /* l_next offset in link_map. */
5205 16 /* l_prev offset in link_map. */
5208 static const struct link_map_offsets lmo_64bit_offsets
=
5210 0, /* r_version offset. */
5211 8, /* r_debug.r_map offset. */
5212 0, /* l_addr offset in link_map. */
5213 8, /* l_name offset in link_map. */
5214 16, /* l_ld offset in link_map. */
5215 24, /* l_next offset in link_map. */
5216 32 /* l_prev offset in link_map. */
5218 const struct link_map_offsets
*lmo
;
5220 if (writebuf
!= NULL
)
5222 if (readbuf
== NULL
)
5225 pid
= lwpid_of (get_thread_lwp (current_inferior
));
5226 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5227 is_elf64
= elf_64_file_p (filename
);
5228 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5230 if (priv
->r_debug
== 0)
5231 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5233 if (priv
->r_debug
== (CORE_ADDR
) -1 || priv
->r_debug
== 0)
5235 document
= xstrdup ("<library-list-svr4 version=\"1.0\"/>\n");
5239 int allocated
= 1024;
5241 const int ptr_size
= is_elf64
? 8 : 4;
5242 CORE_ADDR lm_addr
, lm_prev
, l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5243 int r_version
, header_done
= 0;
5245 document
= xmalloc (allocated
);
5246 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5247 p
= document
+ strlen (document
);
5250 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5251 (unsigned char *) &r_version
,
5252 sizeof (r_version
)) != 0
5255 warning ("unexpected r_debug version %d", r_version
);
5259 if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5260 &lm_addr
, ptr_size
) != 0)
5262 warning ("unable to read r_map from 0x%lx",
5263 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5268 while (read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5269 &l_name
, ptr_size
) == 0
5270 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5271 &l_addr
, ptr_size
) == 0
5272 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5273 &l_ld
, ptr_size
) == 0
5274 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5275 &l_prev
, ptr_size
) == 0
5276 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5277 &l_next
, ptr_size
) == 0)
5279 unsigned char libname
[PATH_MAX
];
5281 if (lm_prev
!= l_prev
)
5283 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5284 (long) lm_prev
, (long) l_prev
);
5288 /* Not checking for error because reading may stop before
5289 we've got PATH_MAX worth of characters. */
5291 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5292 libname
[sizeof (libname
) - 1] = '\0';
5293 if (libname
[0] != '\0')
5295 /* 6x the size for xml_escape_text below. */
5296 size_t len
= 6 * strlen ((char *) libname
);
5301 /* Terminate `<library-list-svr4'. */
5306 while (allocated
< p
- document
+ len
+ 200)
5308 /* Expand to guarantee sufficient storage. */
5309 uintptr_t document_len
= p
- document
;
5311 document
= xrealloc (document
, 2 * allocated
);
5313 p
= document
+ document_len
;
5316 name
= xml_escape_text ((char *) libname
);
5317 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
5318 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5319 name
, (unsigned long) lm_addr
,
5320 (unsigned long) l_addr
, (unsigned long) l_ld
);
5323 else if (lm_prev
== 0)
5325 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5336 strcpy (p
, "</library-list-svr4>");
5339 document_len
= strlen (document
);
5340 if (offset
< document_len
)
5341 document_len
-= offset
;
5344 if (len
> document_len
)
5347 memcpy (readbuf
, document
+ offset
, len
);
5353 static struct target_ops linux_target_ops
= {
5354 linux_create_inferior
,
5363 linux_fetch_registers
,
5364 linux_store_registers
,
5365 linux_prepare_to_access_memory
,
5366 linux_done_accessing_memory
,
5369 linux_look_up_symbols
,
5370 linux_request_interrupt
,
5374 linux_stopped_by_watchpoint
,
5375 linux_stopped_data_address
,
5376 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
5381 #ifdef USE_THREAD_DB
5382 thread_db_get_tls_address
,
5387 hostio_last_error_from_errno
,
5390 linux_supports_non_stop
,
5392 linux_start_non_stop
,
5393 linux_supports_multi_process
,
5394 #ifdef USE_THREAD_DB
5395 thread_db_handle_monitor_command
,
5399 linux_common_core_of_thread
,
5401 linux_process_qsupported
,
5402 linux_supports_tracepoints
,
5405 linux_thread_stopped
,
5409 linux_cancel_breakpoints
,
5410 linux_stabilize_threads
,
5411 linux_install_fast_tracepoint_jump_pad
,
5413 linux_supports_disable_randomization
,
5414 linux_get_min_fast_tracepoint_insn_len
,
5415 linux_qxfer_libraries_svr4
,
5419 linux_init_signals ()
5421 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5422 to find what the cancel signal actually is. */
5423 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
5424 signal (__SIGRTMIN
+1, SIG_IGN
);
5429 initialize_low (void)
5431 struct sigaction sigchld_action
;
5432 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
5433 set_target_ops (&linux_target_ops
);
5434 set_breakpoint_data (the_low_target
.breakpoint
,
5435 the_low_target
.breakpoint_len
);
5436 linux_init_signals ();
5437 linux_test_for_tracefork ();
5438 #ifdef HAVE_LINUX_REGSETS
5439 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
5441 disabled_regsets
= xmalloc (num_regsets
);
5444 sigchld_action
.sa_handler
= sigchld_handler
;
5445 sigemptyset (&sigchld_action
.sa_mask
);
5446 sigchld_action
.sa_flags
= SA_RESTART
;
5447 sigaction (SIGCHLD
, &sigchld_action
, NULL
);