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 /* Return non-zero if HEADER is a 64-bit ELF file. */
192 elf_64_header_p (const Elf64_Ehdr
*header
)
194 return (header
->e_ident
[EI_MAG0
] == ELFMAG0
195 && header
->e_ident
[EI_MAG1
] == ELFMAG1
196 && header
->e_ident
[EI_MAG2
] == ELFMAG2
197 && header
->e_ident
[EI_MAG3
] == ELFMAG3
198 && header
->e_ident
[EI_CLASS
] == ELFCLASS64
);
201 /* Return non-zero if FILE is a 64-bit ELF file,
202 zero if the file is not a 64-bit ELF file,
203 and -1 if the file is not accessible or doesn't exist. */
206 elf_64_file_p (const char *file
)
211 fd
= open (file
, O_RDONLY
);
215 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
222 return elf_64_header_p (&header
);
225 /* Accepts an integer PID; Returns true if the executable PID is
226 running is a 64-bit ELF file.. */
229 linux_pid_exe_is_elf_64_file (int pid
)
231 char file
[MAXPATHLEN
];
233 sprintf (file
, "/proc/%d/exe", pid
);
234 return elf_64_file_p (file
);
238 delete_lwp (struct lwp_info
*lwp
)
240 remove_thread (get_lwp_thread (lwp
));
241 remove_inferior (&all_lwps
, &lwp
->head
);
242 free (lwp
->arch_private
);
246 /* Add a process to the common process list, and set its private
249 static struct process_info
*
250 linux_add_process (int pid
, int attached
)
252 struct process_info
*proc
;
254 /* Is this the first process? If so, then set the arch. */
255 if (all_processes
.head
== NULL
)
258 proc
= add_process (pid
, attached
);
259 proc
->private = xcalloc (1, sizeof (*proc
->private));
261 if (the_low_target
.new_process
!= NULL
)
262 proc
->private->arch_private
= the_low_target
.new_process ();
267 /* Wrapper function for waitpid which handles EINTR, and emulates
268 __WALL for systems where that is not available. */
271 my_waitpid (int pid
, int *status
, int flags
)
276 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
280 sigset_t block_mask
, org_mask
, wake_mask
;
283 wnohang
= (flags
& WNOHANG
) != 0;
284 flags
&= ~(__WALL
| __WCLONE
);
287 /* Block all signals while here. This avoids knowing about
288 LinuxThread's signals. */
289 sigfillset (&block_mask
);
290 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
292 /* ... except during the sigsuspend below. */
293 sigemptyset (&wake_mask
);
297 /* Since all signals are blocked, there's no need to check
299 ret
= waitpid (pid
, status
, flags
);
302 if (ret
== -1 && out_errno
!= ECHILD
)
307 if (flags
& __WCLONE
)
309 /* We've tried both flavors now. If WNOHANG is set,
310 there's nothing else to do, just bail out. */
315 fprintf (stderr
, "blocking\n");
317 /* Block waiting for signals. */
318 sigsuspend (&wake_mask
);
324 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
329 ret
= waitpid (pid
, status
, flags
);
330 while (ret
== -1 && errno
== EINTR
);
335 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
336 pid
, flags
, status
? *status
: -1, ret
);
342 /* Handle a GNU/Linux extended wait response. If we see a clone
343 event, we need to add the new LWP to our list (and not report the
344 trap to higher layers). */
347 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
349 int event
= wstat
>> 16;
350 struct lwp_info
*new_lwp
;
352 if (event
== PTRACE_EVENT_CLONE
)
355 unsigned long new_pid
;
356 int ret
, status
= W_STOPCODE (SIGSTOP
);
358 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), 0, &new_pid
);
360 /* If we haven't already seen the new PID stop, wait for it now. */
361 if (! pull_pid_from_list (&stopped_pids
, new_pid
))
363 /* The new child has a pending SIGSTOP. We can't affect it until it
364 hits the SIGSTOP, but we're already attached. */
366 ret
= my_waitpid (new_pid
, &status
, __WALL
);
369 perror_with_name ("waiting for new child");
370 else if (ret
!= new_pid
)
371 warning ("wait returned unexpected PID %d", ret
);
372 else if (!WIFSTOPPED (status
))
373 warning ("wait returned unexpected status 0x%x", status
);
376 linux_enable_event_reporting (new_pid
);
378 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
379 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
380 add_thread (ptid
, new_lwp
);
382 /* Either we're going to immediately resume the new thread
383 or leave it stopped. linux_resume_one_lwp is a nop if it
384 thinks the thread is currently running, so set this first
385 before calling linux_resume_one_lwp. */
386 new_lwp
->stopped
= 1;
388 /* Normally we will get the pending SIGSTOP. But in some cases
389 we might get another signal delivered to the group first.
390 If we do get another signal, be sure not to lose it. */
391 if (WSTOPSIG (status
) == SIGSTOP
)
393 if (stopping_threads
)
394 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
396 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
400 new_lwp
->stop_expected
= 1;
402 if (stopping_threads
)
404 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
405 new_lwp
->status_pending_p
= 1;
406 new_lwp
->status_pending
= status
;
409 /* Pass the signal on. This is what GDB does - except
410 shouldn't we really report it instead? */
411 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
414 /* Always resume the current thread. If we are stopping
415 threads, it will have a pending SIGSTOP; we may as well
417 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
421 /* Return the PC as read from the regcache of LWP, without any
425 get_pc (struct lwp_info
*lwp
)
427 struct thread_info
*saved_inferior
;
428 struct regcache
*regcache
;
431 if (the_low_target
.get_pc
== NULL
)
434 saved_inferior
= current_inferior
;
435 current_inferior
= get_lwp_thread (lwp
);
437 regcache
= get_thread_regcache (current_inferior
, 1);
438 pc
= (*the_low_target
.get_pc
) (regcache
);
441 fprintf (stderr
, "pc is 0x%lx\n", (long) pc
);
443 current_inferior
= saved_inferior
;
447 /* This function should only be called if LWP got a SIGTRAP.
448 The SIGTRAP could mean several things.
450 On i386, where decr_pc_after_break is non-zero:
451 If we were single-stepping this process using PTRACE_SINGLESTEP,
452 we will get only the one SIGTRAP (even if the instruction we
453 stepped over was a breakpoint). The value of $eip will be the
455 If we continue the process using PTRACE_CONT, we will get a
456 SIGTRAP when we hit a breakpoint. The value of $eip will be
457 the instruction after the breakpoint (i.e. needs to be
458 decremented). If we report the SIGTRAP to GDB, we must also
459 report the undecremented PC. If we cancel the SIGTRAP, we
460 must resume at the decremented PC.
462 (Presumably, not yet tested) On a non-decr_pc_after_break machine
463 with hardware or kernel single-step:
464 If we single-step over a breakpoint instruction, our PC will
465 point at the following instruction. If we continue and hit a
466 breakpoint instruction, our PC will point at the breakpoint
470 get_stop_pc (struct lwp_info
*lwp
)
474 if (the_low_target
.get_pc
== NULL
)
477 stop_pc
= get_pc (lwp
);
479 if (WSTOPSIG (lwp
->last_status
) == SIGTRAP
481 && !lwp
->stopped_by_watchpoint
482 && lwp
->last_status
>> 16 == 0)
483 stop_pc
-= the_low_target
.decr_pc_after_break
;
486 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
492 add_lwp (ptid_t ptid
)
494 struct lwp_info
*lwp
;
496 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
497 memset (lwp
, 0, sizeof (*lwp
));
501 if (the_low_target
.new_thread
!= NULL
)
502 lwp
->arch_private
= the_low_target
.new_thread ();
504 add_inferior_to_list (&all_lwps
, &lwp
->head
);
509 /* Start an inferior process and returns its pid.
510 ALLARGS is a vector of program-name and args. */
513 linux_create_inferior (char *program
, char **allargs
)
515 #ifdef HAVE_PERSONALITY
516 int personality_orig
= 0, personality_set
= 0;
518 struct lwp_info
*new_lwp
;
522 #ifdef HAVE_PERSONALITY
523 if (disable_randomization
)
526 personality_orig
= personality (0xffffffff);
527 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
530 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
532 if (errno
!= 0 || (personality_set
533 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
534 warning ("Error disabling address space randomization: %s",
539 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
545 perror_with_name ("fork");
549 ptrace (PTRACE_TRACEME
, 0, 0, 0);
551 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
552 signal (__SIGRTMIN
+ 1, SIG_DFL
);
557 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
558 stdout to stderr so that inferior i/o doesn't corrupt the connection.
559 Also, redirect stdin to /dev/null. */
560 if (remote_connection_is_stdio ())
563 open ("/dev/null", O_RDONLY
);
565 if (write (2, "stdin/stdout redirected\n",
566 sizeof ("stdin/stdout redirected\n") - 1) < 0)
567 /* Errors ignored. */;
570 execv (program
, allargs
);
572 execvp (program
, allargs
);
574 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
580 #ifdef HAVE_PERSONALITY
584 personality (personality_orig
);
586 warning ("Error restoring address space randomization: %s",
591 linux_add_process (pid
, 0);
593 ptid
= ptid_build (pid
, pid
, 0);
594 new_lwp
= add_lwp (ptid
);
595 add_thread (ptid
, new_lwp
);
596 new_lwp
->must_set_ptrace_flags
= 1;
601 /* Detect `T (stopped)' in `/proc/PID/status'.
602 Other states including `T (tracing stop)' are reported as false. */
605 pid_is_stopped (pid_t pid
)
611 snprintf (buf
, sizeof (buf
), "/proc/%d/status", (int) pid
);
612 status_file
= fopen (buf
, "r");
613 if (status_file
!= NULL
)
617 while (fgets (buf
, sizeof (buf
), status_file
))
619 if (strncmp (buf
, "State:", 6) == 0)
625 if (have_state
&& strstr (buf
, "T (stopped)") != NULL
)
627 fclose (status_file
);
632 /* Attach to an inferior process. */
635 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
638 struct lwp_info
*new_lwp
;
640 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) != 0)
644 /* If we fail to attach to an LWP, just warn. */
645 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
646 strerror (errno
), errno
);
651 /* If we fail to attach to a process, report an error. */
652 error ("Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
653 strerror (errno
), errno
);
657 /* If lwp is the tgid, we handle adding existing threads later.
658 Otherwise we just add lwp without bothering about any other
660 ptid
= ptid_build (lwpid
, lwpid
, 0);
663 /* Note that extracting the pid from the current inferior is
664 safe, since we're always called in the context of the same
665 process as this new thread. */
666 int pid
= pid_of (get_thread_lwp (current_inferior
));
667 ptid
= ptid_build (pid
, lwpid
, 0);
670 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
671 add_thread (ptid
, new_lwp
);
673 /* We need to wait for SIGSTOP before being able to make the next
674 ptrace call on this LWP. */
675 new_lwp
->must_set_ptrace_flags
= 1;
677 if (pid_is_stopped (lwpid
))
681 "Attached to a stopped process\n");
683 /* The process is definitely stopped. It is in a job control
684 stop, unless the kernel predates the TASK_STOPPED /
685 TASK_TRACED distinction, in which case it might be in a
686 ptrace stop. Make sure it is in a ptrace stop; from there we
687 can kill it, signal it, et cetera.
689 First make sure there is a pending SIGSTOP. Since we are
690 already attached, the process can not transition from stopped
691 to running without a PTRACE_CONT; so we know this signal will
692 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
693 probably already in the queue (unless this kernel is old
694 enough to use TASK_STOPPED for ptrace stops); but since
695 SIGSTOP is not an RT signal, it can only be queued once. */
696 kill_lwp (lwpid
, SIGSTOP
);
698 /* Finally, resume the stopped process. This will deliver the
699 SIGSTOP (or a higher priority signal, just like normal
700 PTRACE_ATTACH), which we'll catch later on. */
701 ptrace (PTRACE_CONT
, lwpid
, 0, 0);
704 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
707 There are several cases to consider here:
709 1) gdbserver has already attached to the process and is being notified
710 of a new thread that is being created.
711 In this case we should ignore that SIGSTOP and resume the
712 process. This is handled below by setting stop_expected = 1,
713 and the fact that add_thread sets last_resume_kind ==
716 2) This is the first thread (the process thread), and we're attaching
717 to it via attach_inferior.
718 In this case we want the process thread to stop.
719 This is handled by having linux_attach set last_resume_kind ==
720 resume_stop after we return.
722 If the pid we are attaching to is also the tgid, we attach to and
723 stop all the existing threads. Otherwise, we attach to pid and
724 ignore any other threads in the same group as this pid.
726 3) GDB is connecting to gdbserver and is requesting an enumeration of all
728 In this case we want the thread to stop.
729 FIXME: This case is currently not properly handled.
730 We should wait for the SIGSTOP but don't. Things work apparently
731 because enough time passes between when we ptrace (ATTACH) and when
732 gdb makes the next ptrace call on the thread.
734 On the other hand, if we are currently trying to stop all threads, we
735 should treat the new thread as if we had sent it a SIGSTOP. This works
736 because we are guaranteed that the add_lwp call above added us to the
737 end of the list, and so the new thread has not yet reached
738 wait_for_sigstop (but will). */
739 new_lwp
->stop_expected
= 1;
743 linux_attach_lwp (unsigned long lwpid
)
745 linux_attach_lwp_1 (lwpid
, 0);
748 /* Attach to PID. If PID is the tgid, attach to it and all
752 linux_attach (unsigned long pid
)
754 /* Attach to PID. We will check for other threads
756 linux_attach_lwp_1 (pid
, 1);
757 linux_add_process (pid
, 1);
761 struct thread_info
*thread
;
763 /* Don't ignore the initial SIGSTOP if we just attached to this
764 process. It will be collected by wait shortly. */
765 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
766 thread
->last_resume_kind
= resume_stop
;
769 if (linux_proc_get_tgid (pid
) == pid
)
774 sprintf (pathname
, "/proc/%ld/task", pid
);
776 dir
= opendir (pathname
);
780 fprintf (stderr
, "Could not open /proc/%ld/task.\n", pid
);
785 /* At this point we attached to the tgid. Scan the task for
788 int new_threads_found
;
792 while (iterations
< 2)
794 new_threads_found
= 0;
795 /* Add all the other threads. While we go through the
796 threads, new threads may be spawned. Cycle through
797 the list of threads until we have done two iterations without
798 finding new threads. */
799 while ((dp
= readdir (dir
)) != NULL
)
802 lwp
= strtoul (dp
->d_name
, NULL
, 10);
804 /* Is this a new thread? */
806 && find_thread_ptid (ptid_build (pid
, lwp
, 0)) == NULL
)
808 linux_attach_lwp_1 (lwp
, 0);
813 Found and attached to new lwp %ld\n", lwp
);
817 if (!new_threads_found
)
838 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
840 struct counter
*counter
= args
;
842 if (ptid_get_pid (entry
->id
) == counter
->pid
)
844 if (++counter
->count
> 1)
852 last_thread_of_process_p (struct thread_info
*thread
)
854 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
855 int pid
= ptid_get_pid (ptid
);
856 struct counter counter
= { pid
, 0 };
858 return (find_inferior (&all_threads
,
859 second_thread_of_pid_p
, &counter
) == NULL
);
865 linux_kill_one_lwp (struct lwp_info
*lwp
)
867 int pid
= lwpid_of (lwp
);
869 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
870 there is no signal context, and ptrace(PTRACE_KILL) (or
871 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
872 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
873 alternative is to kill with SIGKILL. We only need one SIGKILL
874 per process, not one for each thread. But since we still support
875 linuxthreads, and we also support debugging programs using raw
876 clone without CLONE_THREAD, we send one for each thread. For
877 years, we used PTRACE_KILL only, so we're being a bit paranoid
878 about some old kernels where PTRACE_KILL might work better
879 (dubious if there are any such, but that's why it's paranoia), so
880 we try SIGKILL first, PTRACE_KILL second, and so we're fine
887 "LKL: kill (SIGKILL) %s, 0, 0 (%s)\n",
888 target_pid_to_str (ptid_of (lwp
)),
889 errno
? strerror (errno
) : "OK");
892 ptrace (PTRACE_KILL
, pid
, 0, 0);
895 "LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
896 target_pid_to_str (ptid_of (lwp
)),
897 errno
? strerror (errno
) : "OK");
900 /* Callback for `find_inferior'. Kills an lwp of a given process,
901 except the leader. */
904 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
906 struct thread_info
*thread
= (struct thread_info
*) entry
;
907 struct lwp_info
*lwp
= get_thread_lwp (thread
);
909 int pid
= * (int *) args
;
911 if (ptid_get_pid (entry
->id
) != pid
)
914 /* We avoid killing the first thread here, because of a Linux kernel (at
915 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
916 the children get a chance to be reaped, it will remain a zombie
919 if (lwpid_of (lwp
) == pid
)
922 fprintf (stderr
, "lkop: is last of process %s\n",
923 target_pid_to_str (entry
->id
));
929 linux_kill_one_lwp (lwp
);
931 /* Make sure it died. The loop is most likely unnecessary. */
932 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
933 } while (pid
> 0 && WIFSTOPPED (wstat
));
941 struct process_info
*process
;
942 struct lwp_info
*lwp
;
946 process
= find_process_pid (pid
);
950 /* If we're killing a running inferior, make sure it is stopped
951 first, as PTRACE_KILL will not work otherwise. */
952 stop_all_lwps (0, NULL
);
954 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
956 /* See the comment in linux_kill_one_lwp. We did not kill the first
957 thread in the list, so do so now. */
958 lwp
= find_lwp_pid (pid_to_ptid (pid
));
963 fprintf (stderr
, "lk_1: cannot find lwp %ld, for pid: %d\n",
964 lwpid_of (lwp
), pid
);
969 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
970 lwpid_of (lwp
), pid
);
974 linux_kill_one_lwp (lwp
);
976 /* Make sure it died. The loop is most likely unnecessary. */
977 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
978 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
981 the_target
->mourn (process
);
983 /* Since we presently can only stop all lwps of all processes, we
984 need to unstop lwps of other processes. */
985 unstop_all_lwps (0, NULL
);
990 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
992 struct thread_info
*thread
= (struct thread_info
*) entry
;
993 struct lwp_info
*lwp
= get_thread_lwp (thread
);
994 int pid
= * (int *) args
;
996 if (ptid_get_pid (entry
->id
) != pid
)
999 /* If this process is stopped but is expecting a SIGSTOP, then make
1000 sure we take care of that now. This isn't absolutely guaranteed
1001 to collect the SIGSTOP, but is fairly likely to. */
1002 if (lwp
->stop_expected
)
1005 /* Clear stop_expected, so that the SIGSTOP will be reported. */
1006 lwp
->stop_expected
= 0;
1007 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
1008 linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
1011 /* Flush any pending changes to the process's registers. */
1012 regcache_invalidate_one ((struct inferior_list_entry
*)
1013 get_lwp_thread (lwp
));
1015 /* Finally, let it resume. */
1016 if (the_low_target
.prepare_to_resume
!= NULL
)
1017 the_low_target
.prepare_to_resume (lwp
);
1018 ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0, 0);
1025 linux_detach (int pid
)
1027 struct process_info
*process
;
1029 process
= find_process_pid (pid
);
1030 if (process
== NULL
)
1033 /* Stop all threads before detaching. First, ptrace requires that
1034 the thread is stopped to sucessfully detach. Second, thread_db
1035 may need to uninstall thread event breakpoints from memory, which
1036 only works with a stopped process anyway. */
1037 stop_all_lwps (0, NULL
);
1039 #ifdef USE_THREAD_DB
1040 thread_db_detach (process
);
1043 /* Stabilize threads (move out of jump pads). */
1044 stabilize_threads ();
1046 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1048 the_target
->mourn (process
);
1050 /* Since we presently can only stop all lwps of all processes, we
1051 need to unstop lwps of other processes. */
1052 unstop_all_lwps (0, NULL
);
1056 /* Remove all LWPs that belong to process PROC from the lwp list. */
1059 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1061 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1062 struct process_info
*process
= proc
;
1064 if (pid_of (lwp
) == pid_of (process
))
1071 linux_mourn (struct process_info
*process
)
1073 struct process_info_private
*priv
;
1075 #ifdef USE_THREAD_DB
1076 thread_db_mourn (process
);
1079 find_inferior (&all_lwps
, delete_lwp_callback
, process
);
1081 /* Freeing all private data. */
1082 priv
= process
->private;
1083 free (priv
->arch_private
);
1085 process
->private = NULL
;
1087 remove_process (process
);
1091 linux_join (int pid
)
1096 ret
= my_waitpid (pid
, &status
, 0);
1097 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1099 } while (ret
!= -1 || errno
!= ECHILD
);
1102 /* Return nonzero if the given thread is still alive. */
1104 linux_thread_alive (ptid_t ptid
)
1106 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1108 /* We assume we always know if a thread exits. If a whole process
1109 exited but we still haven't been able to report it to GDB, we'll
1110 hold on to the last lwp of the dead process. */
1117 /* Return 1 if this lwp has an interesting status pending. */
1119 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1121 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1122 ptid_t ptid
= * (ptid_t
*) arg
;
1123 struct thread_info
*thread
;
1125 /* Check if we're only interested in events from a specific process
1127 if (!ptid_equal (minus_one_ptid
, ptid
)
1128 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
1131 thread
= get_lwp_thread (lwp
);
1133 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1134 report any status pending the LWP may have. */
1135 if (thread
->last_resume_kind
== resume_stop
1136 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1139 return lwp
->status_pending_p
;
1143 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1145 ptid_t ptid
= *(ptid_t
*) data
;
1148 if (ptid_get_lwp (ptid
) != 0)
1149 lwp
= ptid_get_lwp (ptid
);
1151 lwp
= ptid_get_pid (ptid
);
1153 if (ptid_get_lwp (entry
->id
) == lwp
)
1160 find_lwp_pid (ptid_t ptid
)
1162 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
1165 static struct lwp_info
*
1166 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
1169 int to_wait_for
= -1;
1170 struct lwp_info
*child
= NULL
;
1173 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1175 if (ptid_equal (ptid
, minus_one_ptid
))
1176 to_wait_for
= -1; /* any child */
1178 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1184 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1185 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1188 perror_with_name ("waitpid");
1191 && (!WIFSTOPPED (*wstatp
)
1192 || (WSTOPSIG (*wstatp
) != 32
1193 && WSTOPSIG (*wstatp
) != 33)))
1194 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1196 child
= find_lwp_pid (pid_to_ptid (ret
));
1198 /* If we didn't find a process, one of two things presumably happened:
1199 - A process we started and then detached from has exited. Ignore it.
1200 - A process we are controlling has forked and the new child's stop
1201 was reported to us by the kernel. Save its PID. */
1202 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1204 add_pid_to_list (&stopped_pids
, ret
);
1207 else if (child
== NULL
)
1212 child
->last_status
= *wstatp
;
1214 /* Architecture-specific setup after inferior is running.
1215 This needs to happen after we have attached to the inferior
1216 and it is stopped for the first time, but before we access
1217 any inferior registers. */
1220 the_low_target
.arch_setup ();
1221 #ifdef HAVE_LINUX_REGSETS
1222 memset (disabled_regsets
, 0, num_regsets
);
1227 /* Fetch the possibly triggered data watchpoint info and store it in
1230 On some archs, like x86, that use debug registers to set
1231 watchpoints, it's possible that the way to know which watched
1232 address trapped, is to check the register that is used to select
1233 which address to watch. Problem is, between setting the
1234 watchpoint and reading back which data address trapped, the user
1235 may change the set of watchpoints, and, as a consequence, GDB
1236 changes the debug registers in the inferior. To avoid reading
1237 back a stale stopped-data-address when that happens, we cache in
1238 LP the fact that a watchpoint trapped, and the corresponding data
1239 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1240 changes the debug registers meanwhile, we have the cached data we
1243 if (WIFSTOPPED (*wstatp
) && WSTOPSIG (*wstatp
) == SIGTRAP
)
1245 if (the_low_target
.stopped_by_watchpoint
== NULL
)
1247 child
->stopped_by_watchpoint
= 0;
1251 struct thread_info
*saved_inferior
;
1253 saved_inferior
= current_inferior
;
1254 current_inferior
= get_lwp_thread (child
);
1256 child
->stopped_by_watchpoint
1257 = the_low_target
.stopped_by_watchpoint ();
1259 if (child
->stopped_by_watchpoint
)
1261 if (the_low_target
.stopped_data_address
!= NULL
)
1262 child
->stopped_data_address
1263 = the_low_target
.stopped_data_address ();
1265 child
->stopped_data_address
= 0;
1268 current_inferior
= saved_inferior
;
1272 /* Store the STOP_PC, with adjustment applied. This depends on the
1273 architecture being defined already (so that CHILD has a valid
1274 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1276 if (WIFSTOPPED (*wstatp
))
1277 child
->stop_pc
= get_stop_pc (child
);
1280 && WIFSTOPPED (*wstatp
)
1281 && the_low_target
.get_pc
!= NULL
)
1283 struct thread_info
*saved_inferior
= current_inferior
;
1284 struct regcache
*regcache
;
1287 current_inferior
= get_lwp_thread (child
);
1288 regcache
= get_thread_regcache (current_inferior
, 1);
1289 pc
= (*the_low_target
.get_pc
) (regcache
);
1290 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1291 current_inferior
= saved_inferior
;
1297 /* This function should only be called if the LWP got a SIGTRAP.
1299 Handle any tracepoint steps or hits. Return true if a tracepoint
1300 event was handled, 0 otherwise. */
1303 handle_tracepoints (struct lwp_info
*lwp
)
1305 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1306 int tpoint_related_event
= 0;
1308 /* If this tracepoint hit causes a tracing stop, we'll immediately
1309 uninsert tracepoints. To do this, we temporarily pause all
1310 threads, unpatch away, and then unpause threads. We need to make
1311 sure the unpausing doesn't resume LWP too. */
1314 /* And we need to be sure that any all-threads-stopping doesn't try
1315 to move threads out of the jump pads, as it could deadlock the
1316 inferior (LWP could be in the jump pad, maybe even holding the
1319 /* Do any necessary step collect actions. */
1320 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1322 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1324 /* See if we just hit a tracepoint and do its main collect
1326 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1330 gdb_assert (lwp
->suspended
== 0);
1331 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1333 if (tpoint_related_event
)
1336 fprintf (stderr
, "got a tracepoint event\n");
1343 /* Convenience wrapper. Returns true if LWP is presently collecting a
1347 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1348 struct fast_tpoint_collect_status
*status
)
1350 CORE_ADDR thread_area
;
1352 if (the_low_target
.get_thread_area
== NULL
)
1355 /* Get the thread area address. This is used to recognize which
1356 thread is which when tracing with the in-process agent library.
1357 We don't read anything from the address, and treat it as opaque;
1358 it's the address itself that we assume is unique per-thread. */
1359 if ((*the_low_target
.get_thread_area
) (lwpid_of (lwp
), &thread_area
) == -1)
1362 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1365 /* The reason we resume in the caller, is because we want to be able
1366 to pass lwp->status_pending as WSTAT, and we need to clear
1367 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1368 refuses to resume. */
1371 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1373 struct thread_info
*saved_inferior
;
1375 saved_inferior
= current_inferior
;
1376 current_inferior
= get_lwp_thread (lwp
);
1379 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1380 && supports_fast_tracepoints ()
1381 && in_process_agent_loaded ())
1383 struct fast_tpoint_collect_status status
;
1388 Checking whether LWP %ld needs to move out of the jump pad.\n",
1391 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1394 || (WSTOPSIG (*wstat
) != SIGILL
1395 && WSTOPSIG (*wstat
) != SIGFPE
1396 && WSTOPSIG (*wstat
) != SIGSEGV
1397 && WSTOPSIG (*wstat
) != SIGBUS
))
1399 lwp
->collecting_fast_tracepoint
= r
;
1403 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1405 /* Haven't executed the original instruction yet.
1406 Set breakpoint there, and wait till it's hit,
1407 then single-step until exiting the jump pad. */
1408 lwp
->exit_jump_pad_bkpt
1409 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1414 Checking whether LWP %ld needs to move out of the jump pad...it does\n",
1416 current_inferior
= saved_inferior
;
1423 /* If we get a synchronous signal while collecting, *and*
1424 while executing the (relocated) original instruction,
1425 reset the PC to point at the tpoint address, before
1426 reporting to GDB. Otherwise, it's an IPA lib bug: just
1427 report the signal to GDB, and pray for the best. */
1429 lwp
->collecting_fast_tracepoint
= 0;
1432 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1433 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1436 struct regcache
*regcache
;
1438 /* The si_addr on a few signals references the address
1439 of the faulting instruction. Adjust that as
1441 if ((WSTOPSIG (*wstat
) == SIGILL
1442 || WSTOPSIG (*wstat
) == SIGFPE
1443 || WSTOPSIG (*wstat
) == SIGBUS
1444 || WSTOPSIG (*wstat
) == SIGSEGV
)
1445 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &info
) == 0
1446 /* Final check just to make sure we don't clobber
1447 the siginfo of non-kernel-sent signals. */
1448 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1450 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1451 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &info
);
1454 regcache
= get_thread_regcache (get_lwp_thread (lwp
), 1);
1455 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1456 lwp
->stop_pc
= status
.tpoint_addr
;
1458 /* Cancel any fast tracepoint lock this thread was
1460 force_unlock_trace_buffer ();
1463 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1467 "Cancelling fast exit-jump-pad: removing bkpt. "
1468 "stopping all threads momentarily.\n");
1470 stop_all_lwps (1, lwp
);
1471 cancel_breakpoints ();
1473 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1474 lwp
->exit_jump_pad_bkpt
= NULL
;
1476 unstop_all_lwps (1, lwp
);
1478 gdb_assert (lwp
->suspended
>= 0);
1485 Checking whether LWP %ld needs to move out of the jump pad...no\n",
1488 current_inferior
= saved_inferior
;
1492 /* Enqueue one signal in the "signals to report later when out of the
1496 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1498 struct pending_signals
*p_sig
;
1502 Deferring signal %d for LWP %ld.\n", WSTOPSIG (*wstat
), lwpid_of (lwp
));
1506 struct pending_signals
*sig
;
1508 for (sig
= lwp
->pending_signals_to_report
;
1512 " Already queued %d\n",
1515 fprintf (stderr
, " (no more currently queued signals)\n");
1518 /* Don't enqueue non-RT signals if they are already in the deferred
1519 queue. (SIGSTOP being the easiest signal to see ending up here
1521 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1523 struct pending_signals
*sig
;
1525 for (sig
= lwp
->pending_signals_to_report
;
1529 if (sig
->signal
== WSTOPSIG (*wstat
))
1533 "Not requeuing already queued non-RT signal %d"
1542 p_sig
= xmalloc (sizeof (*p_sig
));
1543 p_sig
->prev
= lwp
->pending_signals_to_report
;
1544 p_sig
->signal
= WSTOPSIG (*wstat
);
1545 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1546 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
1548 lwp
->pending_signals_to_report
= p_sig
;
1551 /* Dequeue one signal from the "signals to report later when out of
1552 the jump pad" list. */
1555 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1557 if (lwp
->pending_signals_to_report
!= NULL
)
1559 struct pending_signals
**p_sig
;
1561 p_sig
= &lwp
->pending_signals_to_report
;
1562 while ((*p_sig
)->prev
!= NULL
)
1563 p_sig
= &(*p_sig
)->prev
;
1565 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1566 if ((*p_sig
)->info
.si_signo
!= 0)
1567 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
1572 fprintf (stderr
, "Reporting deferred signal %d for LWP %ld.\n",
1573 WSTOPSIG (*wstat
), lwpid_of (lwp
));
1577 struct pending_signals
*sig
;
1579 for (sig
= lwp
->pending_signals_to_report
;
1583 " Still queued %d\n",
1586 fprintf (stderr
, " (no more queued signals)\n");
1595 /* Arrange for a breakpoint to be hit again later. We don't keep the
1596 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1597 will handle the current event, eventually we will resume this LWP,
1598 and this breakpoint will trap again. */
1601 cancel_breakpoint (struct lwp_info
*lwp
)
1603 struct thread_info
*saved_inferior
;
1605 /* There's nothing to do if we don't support breakpoints. */
1606 if (!supports_breakpoints ())
1609 /* breakpoint_at reads from current inferior. */
1610 saved_inferior
= current_inferior
;
1611 current_inferior
= get_lwp_thread (lwp
);
1613 if ((*the_low_target
.breakpoint_at
) (lwp
->stop_pc
))
1617 "CB: Push back breakpoint for %s\n",
1618 target_pid_to_str (ptid_of (lwp
)));
1620 /* Back up the PC if necessary. */
1621 if (the_low_target
.decr_pc_after_break
)
1623 struct regcache
*regcache
1624 = get_thread_regcache (current_inferior
, 1);
1625 (*the_low_target
.set_pc
) (regcache
, lwp
->stop_pc
);
1628 current_inferior
= saved_inferior
;
1635 "CB: No breakpoint found at %s for [%s]\n",
1636 paddress (lwp
->stop_pc
),
1637 target_pid_to_str (ptid_of (lwp
)));
1640 current_inferior
= saved_inferior
;
1644 /* When the event-loop is doing a step-over, this points at the thread
1646 ptid_t step_over_bkpt
;
1648 /* Wait for an event from child PID. If PID is -1, wait for any
1649 child. Store the stop status through the status pointer WSTAT.
1650 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1651 event was found and OPTIONS contains WNOHANG. Return the PID of
1652 the stopped child otherwise. */
1655 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1657 struct lwp_info
*event_child
, *requested_child
;
1661 requested_child
= NULL
;
1663 /* Check for a lwp with a pending status. */
1665 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
1667 event_child
= (struct lwp_info
*)
1668 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1669 if (debug_threads
&& event_child
)
1670 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1674 requested_child
= find_lwp_pid (ptid
);
1676 if (!stopping_threads
1677 && requested_child
->status_pending_p
1678 && requested_child
->collecting_fast_tracepoint
)
1680 enqueue_one_deferred_signal (requested_child
,
1681 &requested_child
->status_pending
);
1682 requested_child
->status_pending_p
= 0;
1683 requested_child
->status_pending
= 0;
1684 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
1687 if (requested_child
->suspended
1688 && requested_child
->status_pending_p
)
1689 fatal ("requesting an event out of a suspended child?");
1691 if (requested_child
->status_pending_p
)
1692 event_child
= requested_child
;
1695 if (event_child
!= NULL
)
1698 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1699 lwpid_of (event_child
), event_child
->status_pending
);
1700 *wstat
= event_child
->status_pending
;
1701 event_child
->status_pending_p
= 0;
1702 event_child
->status_pending
= 0;
1703 current_inferior
= get_lwp_thread (event_child
);
1704 return lwpid_of (event_child
);
1707 if (ptid_is_pid (ptid
))
1709 /* A request to wait for a specific tgid. This is not possible
1710 with waitpid, so instead, we wait for any child, and leave
1711 children we're not interested in right now with a pending
1712 status to report later. */
1713 wait_ptid
= minus_one_ptid
;
1718 /* We only enter this loop if no process has a pending wait status. Thus
1719 any action taken in response to a wait status inside this loop is
1720 responding as soon as we detect the status, not after any pending
1724 event_child
= linux_wait_for_lwp (wait_ptid
, wstat
, options
);
1726 if ((options
& WNOHANG
) && event_child
== NULL
)
1729 fprintf (stderr
, "WNOHANG set, no event found\n");
1733 if (event_child
== NULL
)
1734 error ("event from unknown child");
1736 if (ptid_is_pid (ptid
)
1737 && ptid_get_pid (ptid
) != ptid_get_pid (ptid_of (event_child
)))
1739 if (! WIFSTOPPED (*wstat
))
1740 mark_lwp_dead (event_child
, *wstat
);
1743 event_child
->status_pending_p
= 1;
1744 event_child
->status_pending
= *wstat
;
1749 current_inferior
= get_lwp_thread (event_child
);
1751 /* Check for thread exit. */
1752 if (! WIFSTOPPED (*wstat
))
1755 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1757 /* If the last thread is exiting, just return. */
1758 if (last_thread_of_process_p (current_inferior
))
1761 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1762 lwpid_of (event_child
));
1763 return lwpid_of (event_child
);
1768 current_inferior
= (struct thread_info
*) all_threads
.head
;
1770 fprintf (stderr
, "Current inferior is now %ld\n",
1771 lwpid_of (get_thread_lwp (current_inferior
)));
1775 current_inferior
= NULL
;
1777 fprintf (stderr
, "Current inferior is now <NULL>\n");
1780 /* If we were waiting for this particular child to do something...
1781 well, it did something. */
1782 if (requested_child
!= NULL
)
1784 int lwpid
= lwpid_of (event_child
);
1786 /* Cancel the step-over operation --- the thread that
1787 started it is gone. */
1788 if (finish_step_over (event_child
))
1789 unstop_all_lwps (1, event_child
);
1790 delete_lwp (event_child
);
1794 delete_lwp (event_child
);
1796 /* Wait for a more interesting event. */
1800 if (event_child
->must_set_ptrace_flags
)
1802 linux_enable_event_reporting (lwpid_of (event_child
));
1803 event_child
->must_set_ptrace_flags
= 0;
1806 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1807 && *wstat
>> 16 != 0)
1809 handle_extended_wait (event_child
, *wstat
);
1813 if (WIFSTOPPED (*wstat
)
1814 && WSTOPSIG (*wstat
) == SIGSTOP
1815 && event_child
->stop_expected
)
1820 fprintf (stderr
, "Expected stop.\n");
1821 event_child
->stop_expected
= 0;
1823 should_stop
= (current_inferior
->last_resume_kind
== resume_stop
1824 || stopping_threads
);
1828 linux_resume_one_lwp (event_child
,
1829 event_child
->stepping
, 0, NULL
);
1834 return lwpid_of (event_child
);
1841 /* Count the LWP's that have had events. */
1844 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
1846 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1847 struct thread_info
*thread
= get_lwp_thread (lp
);
1850 gdb_assert (count
!= NULL
);
1852 /* Count only resumed LWPs that have a SIGTRAP event pending that
1853 should be reported to GDB. */
1854 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1855 && thread
->last_resume_kind
!= resume_stop
1856 && lp
->status_pending_p
1857 && WIFSTOPPED (lp
->status_pending
)
1858 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1859 && !breakpoint_inserted_here (lp
->stop_pc
))
1865 /* Select the LWP (if any) that is currently being single-stepped. */
1868 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1870 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1871 struct thread_info
*thread
= get_lwp_thread (lp
);
1873 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1874 && thread
->last_resume_kind
== resume_step
1875 && lp
->status_pending_p
)
1881 /* Select the Nth LWP that has had a SIGTRAP event that should be
1885 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1887 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1888 struct thread_info
*thread
= get_lwp_thread (lp
);
1889 int *selector
= data
;
1891 gdb_assert (selector
!= NULL
);
1893 /* Select only resumed LWPs that have a SIGTRAP event pending. */
1894 if (thread
->last_resume_kind
!= resume_stop
1895 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1896 && lp
->status_pending_p
1897 && WIFSTOPPED (lp
->status_pending
)
1898 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1899 && !breakpoint_inserted_here (lp
->stop_pc
))
1900 if ((*selector
)-- == 0)
1907 cancel_breakpoints_callback (struct inferior_list_entry
*entry
, void *data
)
1909 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1910 struct thread_info
*thread
= get_lwp_thread (lp
);
1911 struct lwp_info
*event_lp
= data
;
1913 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
1917 /* If a LWP other than the LWP that we're reporting an event for has
1918 hit a GDB breakpoint (as opposed to some random trap signal),
1919 then just arrange for it to hit it again later. We don't keep
1920 the SIGTRAP status and don't forward the SIGTRAP signal to the
1921 LWP. We will handle the current event, eventually we will resume
1922 all LWPs, and this one will get its breakpoint trap again.
1924 If we do not do this, then we run the risk that the user will
1925 delete or disable the breakpoint, but the LWP will have already
1928 if (thread
->last_resume_kind
!= resume_stop
1929 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1930 && lp
->status_pending_p
1931 && WIFSTOPPED (lp
->status_pending
)
1932 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1934 && !lp
->stopped_by_watchpoint
1935 && cancel_breakpoint (lp
))
1936 /* Throw away the SIGTRAP. */
1937 lp
->status_pending_p
= 0;
1943 linux_cancel_breakpoints (void)
1945 find_inferior (&all_lwps
, cancel_breakpoints_callback
, NULL
);
1948 /* Select one LWP out of those that have events pending. */
1951 select_event_lwp (struct lwp_info
**orig_lp
)
1954 int random_selector
;
1955 struct lwp_info
*event_lp
;
1957 /* Give preference to any LWP that is being single-stepped. */
1959 = (struct lwp_info
*) find_inferior (&all_lwps
,
1960 select_singlestep_lwp_callback
, NULL
);
1961 if (event_lp
!= NULL
)
1965 "SEL: Select single-step %s\n",
1966 target_pid_to_str (ptid_of (event_lp
)));
1970 /* No single-stepping LWP. Select one at random, out of those
1971 which have had SIGTRAP events. */
1973 /* First see how many SIGTRAP events we have. */
1974 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
1976 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
1977 random_selector
= (int)
1978 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
1980 if (debug_threads
&& num_events
> 1)
1982 "SEL: Found %d SIGTRAP events, selecting #%d\n",
1983 num_events
, random_selector
);
1985 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
1986 select_event_lwp_callback
,
1990 if (event_lp
!= NULL
)
1992 /* Switch the event LWP. */
1993 *orig_lp
= event_lp
;
1997 /* Decrement the suspend count of an LWP. */
2000 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2002 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2004 /* Ignore EXCEPT. */
2010 gdb_assert (lwp
->suspended
>= 0);
2014 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2018 unsuspend_all_lwps (struct lwp_info
*except
)
2020 find_inferior (&all_lwps
, unsuspend_one_lwp
, except
);
2023 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2024 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2026 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2027 static ptid_t
linux_wait_1 (ptid_t ptid
,
2028 struct target_waitstatus
*ourstatus
,
2029 int target_options
);
2031 /* Stabilize threads (move out of jump pads).
2033 If a thread is midway collecting a fast tracepoint, we need to
2034 finish the collection and move it out of the jump pad before
2035 reporting the signal.
2037 This avoids recursion while collecting (when a signal arrives
2038 midway, and the signal handler itself collects), which would trash
2039 the trace buffer. In case the user set a breakpoint in a signal
2040 handler, this avoids the backtrace showing the jump pad, etc..
2041 Most importantly, there are certain things we can't do safely if
2042 threads are stopped in a jump pad (or in its callee's). For
2045 - starting a new trace run. A thread still collecting the
2046 previous run, could trash the trace buffer when resumed. The trace
2047 buffer control structures would have been reset but the thread had
2048 no way to tell. The thread could even midway memcpy'ing to the
2049 buffer, which would mean that when resumed, it would clobber the
2050 trace buffer that had been set for a new run.
2052 - we can't rewrite/reuse the jump pads for new tracepoints
2053 safely. Say you do tstart while a thread is stopped midway while
2054 collecting. When the thread is later resumed, it finishes the
2055 collection, and returns to the jump pad, to execute the original
2056 instruction that was under the tracepoint jump at the time the
2057 older run had been started. If the jump pad had been rewritten
2058 since for something else in the new run, the thread would now
2059 execute the wrong / random instructions. */
2062 linux_stabilize_threads (void)
2064 struct thread_info
*save_inferior
;
2065 struct lwp_info
*lwp_stuck
;
2068 = (struct lwp_info
*) find_inferior (&all_lwps
,
2069 stuck_in_jump_pad_callback
, NULL
);
2070 if (lwp_stuck
!= NULL
)
2073 fprintf (stderr
, "can't stabilize, LWP %ld is stuck in jump pad\n",
2074 lwpid_of (lwp_stuck
));
2078 save_inferior
= current_inferior
;
2080 stabilizing_threads
= 1;
2083 for_each_inferior (&all_lwps
, move_out_of_jump_pad_callback
);
2085 /* Loop until all are stopped out of the jump pads. */
2086 while (find_inferior (&all_lwps
, lwp_running
, NULL
) != NULL
)
2088 struct target_waitstatus ourstatus
;
2089 struct lwp_info
*lwp
;
2092 /* Note that we go through the full wait even loop. While
2093 moving threads out of jump pad, we need to be able to step
2094 over internal breakpoints and such. */
2095 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2097 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2099 lwp
= get_thread_lwp (current_inferior
);
2104 if (ourstatus
.value
.sig
!= TARGET_SIGNAL_0
2105 || current_inferior
->last_resume_kind
== resume_stop
)
2107 wstat
= W_STOPCODE (target_signal_to_host (ourstatus
.value
.sig
));
2108 enqueue_one_deferred_signal (lwp
, &wstat
);
2113 find_inferior (&all_lwps
, unsuspend_one_lwp
, NULL
);
2115 stabilizing_threads
= 0;
2117 current_inferior
= save_inferior
;
2122 = (struct lwp_info
*) find_inferior (&all_lwps
,
2123 stuck_in_jump_pad_callback
, NULL
);
2124 if (lwp_stuck
!= NULL
)
2125 fprintf (stderr
, "couldn't stabilize, LWP %ld got stuck in jump pad\n",
2126 lwpid_of (lwp_stuck
));
2130 /* Wait for process, returns status. */
2133 linux_wait_1 (ptid_t ptid
,
2134 struct target_waitstatus
*ourstatus
, int target_options
)
2137 struct lwp_info
*event_child
;
2140 int step_over_finished
;
2141 int bp_explains_trap
;
2142 int maybe_internal_trap
;
2146 /* Translate generic target options into linux options. */
2148 if (target_options
& TARGET_WNOHANG
)
2152 bp_explains_trap
= 0;
2154 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2156 /* If we were only supposed to resume one thread, only wait for
2157 that thread - if it's still alive. If it died, however - which
2158 can happen if we're coming from the thread death case below -
2159 then we need to make sure we restart the other threads. We could
2160 pick a thread at random or restart all; restarting all is less
2163 && !ptid_equal (cont_thread
, null_ptid
)
2164 && !ptid_equal (cont_thread
, minus_one_ptid
))
2166 struct thread_info
*thread
;
2168 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
2171 /* No stepping, no signal - unless one is pending already, of course. */
2174 struct thread_resume resume_info
;
2175 resume_info
.thread
= minus_one_ptid
;
2176 resume_info
.kind
= resume_continue
;
2177 resume_info
.sig
= 0;
2178 linux_resume (&resume_info
, 1);
2184 if (ptid_equal (step_over_bkpt
, null_ptid
))
2185 pid
= linux_wait_for_event (ptid
, &w
, options
);
2189 fprintf (stderr
, "step_over_bkpt set [%s], doing a blocking wait\n",
2190 target_pid_to_str (step_over_bkpt
));
2191 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2194 if (pid
== 0) /* only if TARGET_WNOHANG */
2197 event_child
= get_thread_lwp (current_inferior
);
2199 /* If we are waiting for a particular child, and it exited,
2200 linux_wait_for_event will return its exit status. Similarly if
2201 the last child exited. If this is not the last child, however,
2202 do not report it as exited until there is a 'thread exited' response
2203 available in the remote protocol. Instead, just wait for another event.
2204 This should be safe, because if the thread crashed we will already
2205 have reported the termination signal to GDB; that should stop any
2206 in-progress stepping operations, etc.
2208 Report the exit status of the last thread to exit. This matches
2209 LinuxThreads' behavior. */
2211 if (last_thread_of_process_p (current_inferior
))
2213 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2217 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2218 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2222 "\nChild exited with retcode = %x \n",
2227 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2228 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
2232 "\nChild terminated with signal = %x \n",
2237 return ptid_of (event_child
);
2242 if (!WIFSTOPPED (w
))
2246 /* If this event was not handled before, and is not a SIGTRAP, we
2247 report it. SIGILL and SIGSEGV are also treated as traps in case
2248 a breakpoint is inserted at the current PC. If this target does
2249 not support internal breakpoints at all, we also report the
2250 SIGTRAP without further processing; it's of no concern to us. */
2252 = (supports_breakpoints ()
2253 && (WSTOPSIG (w
) == SIGTRAP
2254 || ((WSTOPSIG (w
) == SIGILL
2255 || WSTOPSIG (w
) == SIGSEGV
)
2256 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2258 if (maybe_internal_trap
)
2260 /* Handle anything that requires bookkeeping before deciding to
2261 report the event or continue waiting. */
2263 /* First check if we can explain the SIGTRAP with an internal
2264 breakpoint, or if we should possibly report the event to GDB.
2265 Do this before anything that may remove or insert a
2267 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2269 /* We have a SIGTRAP, possibly a step-over dance has just
2270 finished. If so, tweak the state machine accordingly,
2271 reinsert breakpoints and delete any reinsert (software
2272 single-step) breakpoints. */
2273 step_over_finished
= finish_step_over (event_child
);
2275 /* Now invoke the callbacks of any internal breakpoints there. */
2276 check_breakpoints (event_child
->stop_pc
);
2278 /* Handle tracepoint data collecting. This may overflow the
2279 trace buffer, and cause a tracing stop, removing
2281 trace_event
= handle_tracepoints (event_child
);
2283 if (bp_explains_trap
)
2285 /* If we stepped or ran into an internal breakpoint, we've
2286 already handled it. So next time we resume (from this
2287 PC), we should step over it. */
2289 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2291 if (breakpoint_here (event_child
->stop_pc
))
2292 event_child
->need_step_over
= 1;
2297 /* We have some other signal, possibly a step-over dance was in
2298 progress, and it should be cancelled too. */
2299 step_over_finished
= finish_step_over (event_child
);
2302 /* We have all the data we need. Either report the event to GDB, or
2303 resume threads and keep waiting for more. */
2305 /* If we're collecting a fast tracepoint, finish the collection and
2306 move out of the jump pad before delivering a signal. See
2307 linux_stabilize_threads. */
2310 && WSTOPSIG (w
) != SIGTRAP
2311 && supports_fast_tracepoints ()
2312 && in_process_agent_loaded ())
2316 "Got signal %d for LWP %ld. Check if we need "
2317 "to defer or adjust it.\n",
2318 WSTOPSIG (w
), lwpid_of (event_child
));
2320 /* Allow debugging the jump pad itself. */
2321 if (current_inferior
->last_resume_kind
!= resume_step
2322 && maybe_move_out_of_jump_pad (event_child
, &w
))
2324 enqueue_one_deferred_signal (event_child
, &w
);
2328 "Signal %d for LWP %ld deferred (in jump pad)\n",
2329 WSTOPSIG (w
), lwpid_of (event_child
));
2331 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2336 if (event_child
->collecting_fast_tracepoint
)
2340 LWP %ld was trying to move out of the jump pad (%d). \
2341 Check if we're already there.\n",
2342 lwpid_of (event_child
),
2343 event_child
->collecting_fast_tracepoint
);
2347 event_child
->collecting_fast_tracepoint
2348 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2350 if (event_child
->collecting_fast_tracepoint
!= 1)
2352 /* No longer need this breakpoint. */
2353 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2357 "No longer need exit-jump-pad bkpt; removing it."
2358 "stopping all threads momentarily.\n");
2360 /* Other running threads could hit this breakpoint.
2361 We don't handle moribund locations like GDB does,
2362 instead we always pause all threads when removing
2363 breakpoints, so that any step-over or
2364 decr_pc_after_break adjustment is always taken
2365 care of while the breakpoint is still
2367 stop_all_lwps (1, event_child
);
2368 cancel_breakpoints ();
2370 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2371 event_child
->exit_jump_pad_bkpt
= NULL
;
2373 unstop_all_lwps (1, event_child
);
2375 gdb_assert (event_child
->suspended
>= 0);
2379 if (event_child
->collecting_fast_tracepoint
== 0)
2383 "fast tracepoint finished "
2384 "collecting successfully.\n");
2386 /* We may have a deferred signal to report. */
2387 if (dequeue_one_deferred_signal (event_child
, &w
))
2390 fprintf (stderr
, "dequeued one signal.\n");
2395 fprintf (stderr
, "no deferred signals.\n");
2397 if (stabilizing_threads
)
2399 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2400 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2401 return ptid_of (event_child
);
2407 /* Check whether GDB would be interested in this event. */
2409 /* If GDB is not interested in this signal, don't stop other
2410 threads, and don't report it to GDB. Just resume the inferior
2411 right away. We do this for threading-related signals as well as
2412 any that GDB specifically requested we ignore. But never ignore
2413 SIGSTOP if we sent it ourselves, and do not ignore signals when
2414 stepping - they may require special handling to skip the signal
2416 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2419 && current_inferior
->last_resume_kind
!= resume_step
2421 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2422 (current_process ()->private->thread_db
!= NULL
2423 && (WSTOPSIG (w
) == __SIGRTMIN
2424 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2427 (pass_signals
[target_signal_from_host (WSTOPSIG (w
))]
2428 && !(WSTOPSIG (w
) == SIGSTOP
2429 && current_inferior
->last_resume_kind
== resume_stop
))))
2431 siginfo_t info
, *info_p
;
2434 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
2435 WSTOPSIG (w
), lwpid_of (event_child
));
2437 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
2441 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2442 WSTOPSIG (w
), info_p
);
2446 /* If GDB wanted this thread to single step, we always want to
2447 report the SIGTRAP, and let GDB handle it. Watchpoints should
2448 always be reported. So should signals we can't explain. A
2449 SIGTRAP we can't explain could be a GDB breakpoint --- we may or
2450 not support Z0 breakpoints. If we do, we're be able to handle
2451 GDB breakpoints on top of internal breakpoints, by handling the
2452 internal breakpoint and still reporting the event to GDB. If we
2453 don't, we're out of luck, GDB won't see the breakpoint hit. */
2454 report_to_gdb
= (!maybe_internal_trap
2455 || current_inferior
->last_resume_kind
== resume_step
2456 || event_child
->stopped_by_watchpoint
2457 || (!step_over_finished
2458 && !bp_explains_trap
&& !trace_event
)
2459 || (gdb_breakpoint_here (event_child
->stop_pc
)
2460 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)));
2462 /* We found no reason GDB would want us to stop. We either hit one
2463 of our own breakpoints, or finished an internal step GDB
2464 shouldn't know about. */
2469 if (bp_explains_trap
)
2470 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2471 if (step_over_finished
)
2472 fprintf (stderr
, "Step-over finished.\n");
2474 fprintf (stderr
, "Tracepoint event.\n");
2477 /* We're not reporting this breakpoint to GDB, so apply the
2478 decr_pc_after_break adjustment to the inferior's regcache
2481 if (the_low_target
.set_pc
!= NULL
)
2483 struct regcache
*regcache
2484 = get_thread_regcache (get_lwp_thread (event_child
), 1);
2485 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2488 /* We may have finished stepping over a breakpoint. If so,
2489 we've stopped and suspended all LWPs momentarily except the
2490 stepping one. This is where we resume them all again. We're
2491 going to keep waiting, so use proceed, which handles stepping
2492 over the next breakpoint. */
2494 fprintf (stderr
, "proceeding all threads.\n");
2496 if (step_over_finished
)
2497 unsuspend_all_lwps (event_child
);
2499 proceed_all_lwps ();
2505 if (current_inferior
->last_resume_kind
== resume_step
)
2506 fprintf (stderr
, "GDB wanted to single-step, reporting event.\n");
2507 if (event_child
->stopped_by_watchpoint
)
2508 fprintf (stderr
, "Stopped by watchpoint.\n");
2509 if (gdb_breakpoint_here (event_child
->stop_pc
))
2510 fprintf (stderr
, "Stopped by GDB breakpoint.\n");
2512 fprintf (stderr
, "Hit a non-gdbserver trap event.\n");
2515 /* Alright, we're going to report a stop. */
2517 if (!non_stop
&& !stabilizing_threads
)
2519 /* In all-stop, stop all threads. */
2520 stop_all_lwps (0, NULL
);
2522 /* If we're not waiting for a specific LWP, choose an event LWP
2523 from among those that have had events. Giving equal priority
2524 to all LWPs that have had events helps prevent
2526 if (ptid_equal (ptid
, minus_one_ptid
))
2528 event_child
->status_pending_p
= 1;
2529 event_child
->status_pending
= w
;
2531 select_event_lwp (&event_child
);
2533 event_child
->status_pending_p
= 0;
2534 w
= event_child
->status_pending
;
2537 /* Now that we've selected our final event LWP, cancel any
2538 breakpoints in other LWPs that have hit a GDB breakpoint.
2539 See the comment in cancel_breakpoints_callback to find out
2541 find_inferior (&all_lwps
, cancel_breakpoints_callback
, event_child
);
2543 /* Stabilize threads (move out of jump pads). */
2544 stabilize_threads ();
2548 /* If we just finished a step-over, then all threads had been
2549 momentarily paused. In all-stop, that's fine, we want
2550 threads stopped by now anyway. In non-stop, we need to
2551 re-resume threads that GDB wanted to be running. */
2552 if (step_over_finished
)
2553 unstop_all_lwps (1, event_child
);
2556 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2558 if (current_inferior
->last_resume_kind
== resume_stop
2559 && WSTOPSIG (w
) == SIGSTOP
)
2561 /* A thread that has been requested to stop by GDB with vCont;t,
2562 and it stopped cleanly, so report as SIG0. The use of
2563 SIGSTOP is an implementation detail. */
2564 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2566 else if (current_inferior
->last_resume_kind
== resume_stop
2567 && WSTOPSIG (w
) != SIGSTOP
)
2569 /* A thread that has been requested to stop by GDB with vCont;t,
2570 but, it stopped for other reasons. */
2571 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2575 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2578 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
2581 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
2582 target_pid_to_str (ptid_of (event_child
)),
2584 ourstatus
->value
.sig
);
2586 return ptid_of (event_child
);
2589 /* Get rid of any pending event in the pipe. */
2591 async_file_flush (void)
2597 ret
= read (linux_event_pipe
[0], &buf
, 1);
2598 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
2601 /* Put something in the pipe, so the event loop wakes up. */
2603 async_file_mark (void)
2607 async_file_flush ();
2610 ret
= write (linux_event_pipe
[1], "+", 1);
2611 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
2613 /* Ignore EAGAIN. If the pipe is full, the event loop will already
2614 be awakened anyway. */
2618 linux_wait (ptid_t ptid
,
2619 struct target_waitstatus
*ourstatus
, int target_options
)
2624 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
2626 /* Flush the async file first. */
2627 if (target_is_async_p ())
2628 async_file_flush ();
2630 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
2632 /* If at least one stop was reported, there may be more. A single
2633 SIGCHLD can signal more than one child stop. */
2634 if (target_is_async_p ()
2635 && (target_options
& TARGET_WNOHANG
) != 0
2636 && !ptid_equal (event_ptid
, null_ptid
))
2642 /* Send a signal to an LWP. */
2645 kill_lwp (unsigned long lwpid
, int signo
)
2647 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2648 fails, then we are not using nptl threads and we should be using kill. */
2652 static int tkill_failed
;
2659 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2660 if (errno
!= ENOSYS
)
2667 return kill (lwpid
, signo
);
2671 linux_stop_lwp (struct lwp_info
*lwp
)
2677 send_sigstop (struct lwp_info
*lwp
)
2681 pid
= lwpid_of (lwp
);
2683 /* If we already have a pending stop signal for this process, don't
2685 if (lwp
->stop_expected
)
2688 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
2694 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
2696 lwp
->stop_expected
= 1;
2697 kill_lwp (pid
, SIGSTOP
);
2701 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
2703 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2705 /* Ignore EXCEPT. */
2716 /* Increment the suspend count of an LWP, and stop it, if not stopped
2719 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
2722 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2724 /* Ignore EXCEPT. */
2730 return send_sigstop_callback (entry
, except
);
2734 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
2736 /* It's dead, really. */
2739 /* Store the exit status for later. */
2740 lwp
->status_pending_p
= 1;
2741 lwp
->status_pending
= wstat
;
2743 /* Prevent trying to stop it. */
2746 /* No further stops are expected from a dead lwp. */
2747 lwp
->stop_expected
= 0;
2751 wait_for_sigstop (struct inferior_list_entry
*entry
)
2753 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2754 struct thread_info
*saved_inferior
;
2763 fprintf (stderr
, "wait_for_sigstop: LWP %ld already stopped\n",
2768 saved_inferior
= current_inferior
;
2769 if (saved_inferior
!= NULL
)
2770 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
2772 saved_tid
= null_ptid
; /* avoid bogus unused warning */
2774 ptid
= lwp
->head
.id
;
2777 fprintf (stderr
, "wait_for_sigstop: pulling one event\n");
2779 pid
= linux_wait_for_event (ptid
, &wstat
, __WALL
);
2781 /* If we stopped with a non-SIGSTOP signal, save it for later
2782 and record the pending SIGSTOP. If the process exited, just
2784 if (WIFSTOPPED (wstat
))
2787 fprintf (stderr
, "LWP %ld stopped with signal %d\n",
2788 lwpid_of (lwp
), WSTOPSIG (wstat
));
2790 if (WSTOPSIG (wstat
) != SIGSTOP
)
2793 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
2794 lwpid_of (lwp
), wstat
);
2796 lwp
->status_pending_p
= 1;
2797 lwp
->status_pending
= wstat
;
2803 fprintf (stderr
, "Process %d exited while stopping LWPs\n", pid
);
2805 lwp
= find_lwp_pid (pid_to_ptid (pid
));
2808 /* Leave this status pending for the next time we're able to
2809 report it. In the mean time, we'll report this lwp as
2810 dead to GDB, so GDB doesn't try to read registers and
2811 memory from it. This can only happen if this was the
2812 last thread of the process; otherwise, PID is removed
2813 from the thread tables before linux_wait_for_event
2815 mark_lwp_dead (lwp
, wstat
);
2819 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
2820 current_inferior
= saved_inferior
;
2824 fprintf (stderr
, "Previously current thread died.\n");
2828 /* We can't change the current inferior behind GDB's back,
2829 otherwise, a subsequent command may apply to the wrong
2831 current_inferior
= NULL
;
2835 /* Set a valid thread as current. */
2836 set_desired_inferior (0);
2841 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
2842 move it out, because we need to report the stop event to GDB. For
2843 example, if the user puts a breakpoint in the jump pad, it's
2844 because she wants to debug it. */
2847 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
2849 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2850 struct thread_info
*thread
= get_lwp_thread (lwp
);
2852 gdb_assert (lwp
->suspended
== 0);
2853 gdb_assert (lwp
->stopped
);
2855 /* Allow debugging the jump pad, gdb_collect, etc.. */
2856 return (supports_fast_tracepoints ()
2857 && in_process_agent_loaded ()
2858 && (gdb_breakpoint_here (lwp
->stop_pc
)
2859 || lwp
->stopped_by_watchpoint
2860 || thread
->last_resume_kind
== resume_step
)
2861 && linux_fast_tracepoint_collecting (lwp
, NULL
));
2865 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
2867 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2868 struct thread_info
*thread
= get_lwp_thread (lwp
);
2871 gdb_assert (lwp
->suspended
== 0);
2872 gdb_assert (lwp
->stopped
);
2874 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
2876 /* Allow debugging the jump pad, gdb_collect, etc. */
2877 if (!gdb_breakpoint_here (lwp
->stop_pc
)
2878 && !lwp
->stopped_by_watchpoint
2879 && thread
->last_resume_kind
!= resume_step
2880 && maybe_move_out_of_jump_pad (lwp
, wstat
))
2884 "LWP %ld needs stabilizing (in jump pad)\n",
2889 lwp
->status_pending_p
= 0;
2890 enqueue_one_deferred_signal (lwp
, wstat
);
2894 "Signal %d for LWP %ld deferred "
2896 WSTOPSIG (*wstat
), lwpid_of (lwp
));
2899 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
2906 lwp_running (struct inferior_list_entry
*entry
, void *data
)
2908 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2917 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
2918 If SUSPEND, then also increase the suspend count of every LWP,
2922 stop_all_lwps (int suspend
, struct lwp_info
*except
)
2924 stopping_threads
= 1;
2927 find_inferior (&all_lwps
, suspend_and_send_sigstop_callback
, except
);
2929 find_inferior (&all_lwps
, send_sigstop_callback
, except
);
2930 for_each_inferior (&all_lwps
, wait_for_sigstop
);
2931 stopping_threads
= 0;
2934 /* Resume execution of the inferior process.
2935 If STEP is nonzero, single-step it.
2936 If SIGNAL is nonzero, give it that signal. */
2939 linux_resume_one_lwp (struct lwp_info
*lwp
,
2940 int step
, int signal
, siginfo_t
*info
)
2942 struct thread_info
*saved_inferior
;
2943 int fast_tp_collecting
;
2945 if (lwp
->stopped
== 0)
2948 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
2950 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
2952 /* Cancel actions that rely on GDB not changing the PC (e.g., the
2953 user used the "jump" command, or "set $pc = foo"). */
2954 if (lwp
->stop_pc
!= get_pc (lwp
))
2956 /* Collecting 'while-stepping' actions doesn't make sense
2958 release_while_stepping_state_list (get_lwp_thread (lwp
));
2961 /* If we have pending signals or status, and a new signal, enqueue the
2962 signal. Also enqueue the signal if we are waiting to reinsert a
2963 breakpoint; it will be picked up again below. */
2965 && (lwp
->status_pending_p
2966 || lwp
->pending_signals
!= NULL
2967 || lwp
->bp_reinsert
!= 0
2968 || fast_tp_collecting
))
2970 struct pending_signals
*p_sig
;
2971 p_sig
= xmalloc (sizeof (*p_sig
));
2972 p_sig
->prev
= lwp
->pending_signals
;
2973 p_sig
->signal
= signal
;
2975 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
2977 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
2978 lwp
->pending_signals
= p_sig
;
2981 if (lwp
->status_pending_p
)
2984 fprintf (stderr
, "Not resuming lwp %ld (%s, signal %d, stop %s);"
2985 " has pending status\n",
2986 lwpid_of (lwp
), step
? "step" : "continue", signal
,
2987 lwp
->stop_expected
? "expected" : "not expected");
2991 saved_inferior
= current_inferior
;
2992 current_inferior
= get_lwp_thread (lwp
);
2995 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
2996 lwpid_of (lwp
), step
? "step" : "continue", signal
,
2997 lwp
->stop_expected
? "expected" : "not expected");
2999 /* This bit needs some thinking about. If we get a signal that
3000 we must report while a single-step reinsert is still pending,
3001 we often end up resuming the thread. It might be better to
3002 (ew) allow a stack of pending events; then we could be sure that
3003 the reinsert happened right away and not lose any signals.
3005 Making this stack would also shrink the window in which breakpoints are
3006 uninserted (see comment in linux_wait_for_lwp) but not enough for
3007 complete correctness, so it won't solve that problem. It may be
3008 worthwhile just to solve this one, however. */
3009 if (lwp
->bp_reinsert
!= 0)
3012 fprintf (stderr
, " pending reinsert at 0x%s\n",
3013 paddress (lwp
->bp_reinsert
));
3015 if (lwp
->bp_reinsert
!= 0 && can_hardware_single_step ())
3017 if (fast_tp_collecting
== 0)
3020 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
3022 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
3029 /* Postpone any pending signal. It was enqueued above. */
3033 if (fast_tp_collecting
== 1)
3037 lwp %ld wants to get out of fast tracepoint jump pad (exit-jump-pad-bkpt)\n",
3040 /* Postpone any pending signal. It was enqueued above. */
3043 else if (fast_tp_collecting
== 2)
3047 lwp %ld wants to get out of fast tracepoint jump pad single-stepping\n",
3050 if (can_hardware_single_step ())
3053 fatal ("moving out of jump pad single-stepping"
3054 " not implemented on this target");
3056 /* Postpone any pending signal. It was enqueued above. */
3060 /* If we have while-stepping actions in this thread set it stepping.
3061 If we have a signal to deliver, it may or may not be set to
3062 SIG_IGN, we don't know. Assume so, and allow collecting
3063 while-stepping into a signal handler. A possible smart thing to
3064 do would be to set an internal breakpoint at the signal return
3065 address, continue, and carry on catching this while-stepping
3066 action only when that breakpoint is hit. A future
3068 if (get_lwp_thread (lwp
)->while_stepping
!= NULL
3069 && can_hardware_single_step ())
3073 "lwp %ld has a while-stepping action -> forcing step.\n",
3078 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
3080 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
3081 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
3082 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
3085 /* If we have pending signals, consume one unless we are trying to
3086 reinsert a breakpoint or we're trying to finish a fast tracepoint
3088 if (lwp
->pending_signals
!= NULL
3089 && lwp
->bp_reinsert
== 0
3090 && fast_tp_collecting
== 0)
3092 struct pending_signals
**p_sig
;
3094 p_sig
= &lwp
->pending_signals
;
3095 while ((*p_sig
)->prev
!= NULL
)
3096 p_sig
= &(*p_sig
)->prev
;
3098 signal
= (*p_sig
)->signal
;
3099 if ((*p_sig
)->info
.si_signo
!= 0)
3100 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
3106 if (the_low_target
.prepare_to_resume
!= NULL
)
3107 the_low_target
.prepare_to_resume (lwp
);
3109 regcache_invalidate_one ((struct inferior_list_entry
*)
3110 get_lwp_thread (lwp
));
3113 lwp
->stopped_by_watchpoint
= 0;
3114 lwp
->stepping
= step
;
3115 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0,
3116 /* Coerce to a uintptr_t first to avoid potential gcc warning
3117 of coercing an 8 byte integer to a 4 byte pointer. */
3118 (PTRACE_ARG4_TYPE
) (uintptr_t) signal
);
3120 current_inferior
= saved_inferior
;
3123 /* ESRCH from ptrace either means that the thread was already
3124 running (an error) or that it is gone (a race condition). If
3125 it's gone, we will get a notification the next time we wait,
3126 so we can ignore the error. We could differentiate these
3127 two, but it's tricky without waiting; the thread still exists
3128 as a zombie, so sending it signal 0 would succeed. So just
3133 perror_with_name ("ptrace");
3137 struct thread_resume_array
3139 struct thread_resume
*resume
;
3143 /* This function is called once per thread. We look up the thread
3144 in RESUME_PTR, and mark the thread with a pointer to the appropriate
3147 This algorithm is O(threads * resume elements), but resume elements
3148 is small (and will remain small at least until GDB supports thread
3151 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3153 struct lwp_info
*lwp
;
3154 struct thread_info
*thread
;
3156 struct thread_resume_array
*r
;
3158 thread
= (struct thread_info
*) entry
;
3159 lwp
= get_thread_lwp (thread
);
3162 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3164 ptid_t ptid
= r
->resume
[ndx
].thread
;
3165 if (ptid_equal (ptid
, minus_one_ptid
)
3166 || ptid_equal (ptid
, entry
->id
)
3167 || (ptid_is_pid (ptid
)
3168 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
3169 || (ptid_get_lwp (ptid
) == -1
3170 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
3172 if (r
->resume
[ndx
].kind
== resume_stop
3173 && thread
->last_resume_kind
== resume_stop
)
3176 fprintf (stderr
, "already %s LWP %ld at GDB's request\n",
3177 thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
3185 lwp
->resume
= &r
->resume
[ndx
];
3186 thread
->last_resume_kind
= lwp
->resume
->kind
;
3188 /* If we had a deferred signal to report, dequeue one now.
3189 This can happen if LWP gets more than one signal while
3190 trying to get out of a jump pad. */
3192 && !lwp
->status_pending_p
3193 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3195 lwp
->status_pending_p
= 1;
3199 "Dequeueing deferred signal %d for LWP %ld, "
3200 "leaving status pending.\n",
3201 WSTOPSIG (lwp
->status_pending
), lwpid_of (lwp
));
3208 /* No resume action for this thread. */
3215 /* Set *FLAG_P if this lwp has an interesting status pending. */
3217 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3219 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3221 /* LWPs which will not be resumed are not interesting, because
3222 we might not wait for them next time through linux_wait. */
3223 if (lwp
->resume
== NULL
)
3226 if (lwp
->status_pending_p
)
3227 * (int *) flag_p
= 1;
3232 /* Return 1 if this lwp that GDB wants running is stopped at an
3233 internal breakpoint that we need to step over. It assumes that any
3234 required STOP_PC adjustment has already been propagated to the
3235 inferior's regcache. */
3238 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3240 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3241 struct thread_info
*thread
;
3242 struct thread_info
*saved_inferior
;
3245 /* LWPs which will not be resumed are not interesting, because we
3246 might not wait for them next time through linux_wait. */
3252 "Need step over [LWP %ld]? Ignoring, not stopped\n",
3257 thread
= get_lwp_thread (lwp
);
3259 if (thread
->last_resume_kind
== resume_stop
)
3263 "Need step over [LWP %ld]? Ignoring, should remain stopped\n",
3268 gdb_assert (lwp
->suspended
>= 0);
3274 "Need step over [LWP %ld]? Ignoring, suspended\n",
3279 if (!lwp
->need_step_over
)
3283 "Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
3286 if (lwp
->status_pending_p
)
3290 "Need step over [LWP %ld]? Ignoring, has pending status.\n",
3295 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3299 /* If the PC has changed since we stopped, then don't do anything,
3300 and let the breakpoint/tracepoint be hit. This happens if, for
3301 instance, GDB handled the decr_pc_after_break subtraction itself,
3302 GDB is OOL stepping this thread, or the user has issued a "jump"
3303 command, or poked thread's registers herself. */
3304 if (pc
!= lwp
->stop_pc
)
3308 "Need step over [LWP %ld]? Cancelling, PC was changed. "
3309 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3310 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
3312 lwp
->need_step_over
= 0;
3316 saved_inferior
= current_inferior
;
3317 current_inferior
= thread
;
3319 /* We can only step over breakpoints we know about. */
3320 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3322 /* Don't step over a breakpoint that GDB expects to hit
3323 though. If the condition is being evaluated on the target's side
3324 and it evaluate to false, step over this breakpoint as well. */
3325 if (gdb_breakpoint_here (pc
)
3326 && gdb_condition_true_at_breakpoint (pc
))
3330 "Need step over [LWP %ld]? yes, but found"
3331 " GDB breakpoint at 0x%s; skipping step over\n",
3332 lwpid_of (lwp
), paddress (pc
));
3334 current_inferior
= saved_inferior
;
3341 "Need step over [LWP %ld]? yes, "
3342 "found breakpoint at 0x%s\n",
3343 lwpid_of (lwp
), paddress (pc
));
3345 /* We've found an lwp that needs stepping over --- return 1 so
3346 that find_inferior stops looking. */
3347 current_inferior
= saved_inferior
;
3349 /* If the step over is cancelled, this is set again. */
3350 lwp
->need_step_over
= 0;
3355 current_inferior
= saved_inferior
;
3359 "Need step over [LWP %ld]? No, no breakpoint found at 0x%s\n",
3360 lwpid_of (lwp
), paddress (pc
));
3365 /* Start a step-over operation on LWP. When LWP stopped at a
3366 breakpoint, to make progress, we need to remove the breakpoint out
3367 of the way. If we let other threads run while we do that, they may
3368 pass by the breakpoint location and miss hitting it. To avoid
3369 that, a step-over momentarily stops all threads while LWP is
3370 single-stepped while the breakpoint is temporarily uninserted from
3371 the inferior. When the single-step finishes, we reinsert the
3372 breakpoint, and let all threads that are supposed to be running,
3375 On targets that don't support hardware single-step, we don't
3376 currently support full software single-stepping. Instead, we only
3377 support stepping over the thread event breakpoint, by asking the
3378 low target where to place a reinsert breakpoint. Since this
3379 routine assumes the breakpoint being stepped over is a thread event
3380 breakpoint, it usually assumes the return address of the current
3381 function is a good enough place to set the reinsert breakpoint. */
3384 start_step_over (struct lwp_info
*lwp
)
3386 struct thread_info
*saved_inferior
;
3392 "Starting step-over on LWP %ld. Stopping all threads\n",
3395 stop_all_lwps (1, lwp
);
3396 gdb_assert (lwp
->suspended
== 0);
3399 fprintf (stderr
, "Done stopping all threads for step-over.\n");
3401 /* Note, we should always reach here with an already adjusted PC,
3402 either by GDB (if we're resuming due to GDB's request), or by our
3403 caller, if we just finished handling an internal breakpoint GDB
3404 shouldn't care about. */
3407 saved_inferior
= current_inferior
;
3408 current_inferior
= get_lwp_thread (lwp
);
3410 lwp
->bp_reinsert
= pc
;
3411 uninsert_breakpoints_at (pc
);
3412 uninsert_fast_tracepoint_jumps_at (pc
);
3414 if (can_hardware_single_step ())
3420 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3421 set_reinsert_breakpoint (raddr
);
3425 current_inferior
= saved_inferior
;
3427 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3429 /* Require next event from this LWP. */
3430 step_over_bkpt
= lwp
->head
.id
;
3434 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3435 start_step_over, if still there, and delete any reinsert
3436 breakpoints we've set, on non hardware single-step targets. */
3439 finish_step_over (struct lwp_info
*lwp
)
3441 if (lwp
->bp_reinsert
!= 0)
3444 fprintf (stderr
, "Finished step over.\n");
3446 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3447 may be no breakpoint to reinsert there by now. */
3448 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3449 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3451 lwp
->bp_reinsert
= 0;
3453 /* Delete any software-single-step reinsert breakpoints. No
3454 longer needed. We don't have to worry about other threads
3455 hitting this trap, and later not being able to explain it,
3456 because we were stepping over a breakpoint, and we hold all
3457 threads but LWP stopped while doing that. */
3458 if (!can_hardware_single_step ())
3459 delete_reinsert_breakpoints ();
3461 step_over_bkpt
= null_ptid
;
3468 /* This function is called once per thread. We check the thread's resume
3469 request, which will tell us whether to resume, step, or leave the thread
3470 stopped; and what signal, if any, it should be sent.
3472 For threads which we aren't explicitly told otherwise, we preserve
3473 the stepping flag; this is used for stepping over gdbserver-placed
3476 If pending_flags was set in any thread, we queue any needed
3477 signals, since we won't actually resume. We already have a pending
3478 event to report, so we don't need to preserve any step requests;
3479 they should be re-issued if necessary. */
3482 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3484 struct lwp_info
*lwp
;
3485 struct thread_info
*thread
;
3487 int leave_all_stopped
= * (int *) arg
;
3490 thread
= (struct thread_info
*) entry
;
3491 lwp
= get_thread_lwp (thread
);
3493 if (lwp
->resume
== NULL
)
3496 if (lwp
->resume
->kind
== resume_stop
)
3499 fprintf (stderr
, "resume_stop request for LWP %ld\n", lwpid_of (lwp
));
3504 fprintf (stderr
, "stopping LWP %ld\n", lwpid_of (lwp
));
3506 /* Stop the thread, and wait for the event asynchronously,
3507 through the event loop. */
3513 fprintf (stderr
, "already stopped LWP %ld\n",
3516 /* The LWP may have been stopped in an internal event that
3517 was not meant to be notified back to GDB (e.g., gdbserver
3518 breakpoint), so we should be reporting a stop event in
3521 /* If the thread already has a pending SIGSTOP, this is a
3522 no-op. Otherwise, something later will presumably resume
3523 the thread and this will cause it to cancel any pending
3524 operation, due to last_resume_kind == resume_stop. If
3525 the thread already has a pending status to report, we
3526 will still report it the next time we wait - see
3527 status_pending_p_callback. */
3529 /* If we already have a pending signal to report, then
3530 there's no need to queue a SIGSTOP, as this means we're
3531 midway through moving the LWP out of the jumppad, and we
3532 will report the pending signal as soon as that is
3534 if (lwp
->pending_signals_to_report
== NULL
)
3538 /* For stop requests, we're done. */
3540 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3544 /* If this thread which is about to be resumed has a pending status,
3545 then don't resume any threads - we can just report the pending
3546 status. Make sure to queue any signals that would otherwise be
3547 sent. In all-stop mode, we do this decision based on if *any*
3548 thread has a pending status. If there's a thread that needs the
3549 step-over-breakpoint dance, then don't resume any other thread
3550 but that particular one. */
3551 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
3556 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
3558 step
= (lwp
->resume
->kind
== resume_step
);
3559 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
3564 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
3566 /* If we have a new signal, enqueue the signal. */
3567 if (lwp
->resume
->sig
!= 0)
3569 struct pending_signals
*p_sig
;
3570 p_sig
= xmalloc (sizeof (*p_sig
));
3571 p_sig
->prev
= lwp
->pending_signals
;
3572 p_sig
->signal
= lwp
->resume
->sig
;
3573 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3575 /* If this is the same signal we were previously stopped by,
3576 make sure to queue its siginfo. We can ignore the return
3577 value of ptrace; if it fails, we'll skip
3578 PTRACE_SETSIGINFO. */
3579 if (WIFSTOPPED (lwp
->last_status
)
3580 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
3581 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
3583 lwp
->pending_signals
= p_sig
;
3587 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3593 linux_resume (struct thread_resume
*resume_info
, size_t n
)
3595 struct thread_resume_array array
= { resume_info
, n
};
3596 struct lwp_info
*need_step_over
= NULL
;
3598 int leave_all_stopped
;
3600 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
3602 /* If there is a thread which would otherwise be resumed, which has
3603 a pending status, then don't resume any threads - we can just
3604 report the pending status. Make sure to queue any signals that
3605 would otherwise be sent. In non-stop mode, we'll apply this
3606 logic to each thread individually. We consume all pending events
3607 before considering to start a step-over (in all-stop). */
3610 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
3612 /* If there is a thread which would otherwise be resumed, which is
3613 stopped at a breakpoint that needs stepping over, then don't
3614 resume any threads - have it step over the breakpoint with all
3615 other threads stopped, then resume all threads again. Make sure
3616 to queue any signals that would otherwise be delivered or
3618 if (!any_pending
&& supports_breakpoints ())
3620 = (struct lwp_info
*) find_inferior (&all_lwps
,
3621 need_step_over_p
, NULL
);
3623 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
3627 if (need_step_over
!= NULL
)
3628 fprintf (stderr
, "Not resuming all, need step over\n");
3629 else if (any_pending
)
3631 "Not resuming, all-stop and found "
3632 "an LWP with pending status\n");
3634 fprintf (stderr
, "Resuming, no pending status or step over needed\n");
3637 /* Even if we're leaving threads stopped, queue all signals we'd
3638 otherwise deliver. */
3639 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
3642 start_step_over (need_step_over
);
3645 /* This function is called once per thread. We check the thread's
3646 last resume request, which will tell us whether to resume, step, or
3647 leave the thread stopped. Any signal the client requested to be
3648 delivered has already been enqueued at this point.
3650 If any thread that GDB wants running is stopped at an internal
3651 breakpoint that needs stepping over, we start a step-over operation
3652 on that particular thread, and leave all others stopped. */
3655 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3657 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3658 struct thread_info
*thread
;
3666 "proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
3671 fprintf (stderr
, " LWP %ld already running\n", lwpid_of (lwp
));
3675 thread
= get_lwp_thread (lwp
);
3677 if (thread
->last_resume_kind
== resume_stop
3678 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
3681 fprintf (stderr
, " client wants LWP to remain %ld stopped\n",
3686 if (lwp
->status_pending_p
)
3689 fprintf (stderr
, " LWP %ld has pending status, leaving stopped\n",
3694 gdb_assert (lwp
->suspended
>= 0);
3699 fprintf (stderr
, " LWP %ld is suspended\n", lwpid_of (lwp
));
3703 if (thread
->last_resume_kind
== resume_stop
3704 && lwp
->pending_signals_to_report
== NULL
3705 && lwp
->collecting_fast_tracepoint
== 0)
3707 /* We haven't reported this LWP as stopped yet (otherwise, the
3708 last_status.kind check above would catch it, and we wouldn't
3709 reach here. This LWP may have been momentarily paused by a
3710 stop_all_lwps call while handling for example, another LWP's
3711 step-over. In that case, the pending expected SIGSTOP signal
3712 that was queued at vCont;t handling time will have already
3713 been consumed by wait_for_sigstop, and so we need to requeue
3714 another one here. Note that if the LWP already has a SIGSTOP
3715 pending, this is a no-op. */
3719 "Client wants LWP %ld to stop. "
3720 "Making sure it has a SIGSTOP pending\n",
3726 step
= thread
->last_resume_kind
== resume_step
;
3727 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3732 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3734 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3740 gdb_assert (lwp
->suspended
>= 0);
3742 return proceed_one_lwp (entry
, except
);
3745 /* When we finish a step-over, set threads running again. If there's
3746 another thread that may need a step-over, now's the time to start
3747 it. Eventually, we'll move all threads past their breakpoints. */
3750 proceed_all_lwps (void)
3752 struct lwp_info
*need_step_over
;
3754 /* If there is a thread which would otherwise be resumed, which is
3755 stopped at a breakpoint that needs stepping over, then don't
3756 resume any threads - have it step over the breakpoint with all
3757 other threads stopped, then resume all threads again. */
3759 if (supports_breakpoints ())
3762 = (struct lwp_info
*) find_inferior (&all_lwps
,
3763 need_step_over_p
, NULL
);
3765 if (need_step_over
!= NULL
)
3768 fprintf (stderr
, "proceed_all_lwps: found "
3769 "thread %ld needing a step-over\n",
3770 lwpid_of (need_step_over
));
3772 start_step_over (need_step_over
);
3778 fprintf (stderr
, "Proceeding, no step-over needed\n");
3780 find_inferior (&all_lwps
, proceed_one_lwp
, NULL
);
3783 /* Stopped LWPs that the client wanted to be running, that don't have
3784 pending statuses, are set to run again, except for EXCEPT, if not
3785 NULL. This undoes a stop_all_lwps call. */
3788 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
3794 "unstopping all lwps, except=(LWP %ld)\n", lwpid_of (except
));
3797 "unstopping all lwps\n");
3801 find_inferior (&all_lwps
, unsuspend_and_proceed_one_lwp
, except
);
3803 find_inferior (&all_lwps
, proceed_one_lwp
, except
);
3806 #ifdef HAVE_LINUX_USRREGS
3809 register_addr (int regnum
)
3813 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
3814 error ("Invalid register number %d.", regnum
);
3816 addr
= the_low_target
.regmap
[regnum
];
3821 /* Fetch one register. */
3823 fetch_register (struct regcache
*regcache
, int regno
)
3830 if (regno
>= the_low_target
.num_regs
)
3832 if ((*the_low_target
.cannot_fetch_register
) (regno
))
3835 regaddr
= register_addr (regno
);
3839 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
3840 & -sizeof (PTRACE_XFER_TYPE
));
3841 buf
= alloca (size
);
3843 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3844 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
3847 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
3848 ptrace (PTRACE_PEEKUSER
, pid
,
3849 /* Coerce to a uintptr_t first to avoid potential gcc warning
3850 of coercing an 8 byte integer to a 4 byte pointer. */
3851 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
, 0);
3852 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
3854 error ("reading register %d: %s", regno
, strerror (errno
));
3857 if (the_low_target
.supply_ptrace_register
)
3858 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
3860 supply_register (regcache
, regno
, buf
);
3863 /* Store one register. */
3865 store_register (struct regcache
*regcache
, int regno
)
3872 if (regno
>= the_low_target
.num_regs
)
3874 if ((*the_low_target
.cannot_store_register
) (regno
))
3877 regaddr
= register_addr (regno
);
3881 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
3882 & -sizeof (PTRACE_XFER_TYPE
));
3883 buf
= alloca (size
);
3884 memset (buf
, 0, size
);
3886 if (the_low_target
.collect_ptrace_register
)
3887 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
3889 collect_register (regcache
, regno
, buf
);
3891 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3892 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
3895 ptrace (PTRACE_POKEUSER
, pid
,
3896 /* Coerce to a uintptr_t first to avoid potential gcc warning
3897 about coercing an 8 byte integer to a 4 byte pointer. */
3898 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
,
3899 (PTRACE_ARG4_TYPE
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
3902 /* At this point, ESRCH should mean the process is
3903 already gone, in which case we simply ignore attempts
3904 to change its registers. See also the related
3905 comment in linux_resume_one_lwp. */
3909 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
3910 error ("writing register %d: %s", regno
, strerror (errno
));
3912 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
3916 /* Fetch all registers, or just one, from the child process. */
3918 usr_fetch_inferior_registers (struct regcache
*regcache
, int regno
)
3921 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
3922 fetch_register (regcache
, regno
);
3924 fetch_register (regcache
, regno
);
3927 /* Store our register values back into the inferior.
3928 If REGNO is -1, do this for all registers.
3929 Otherwise, REGNO specifies which register (so we can save time). */
3931 usr_store_inferior_registers (struct regcache
*regcache
, int regno
)
3934 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
3935 store_register (regcache
, regno
);
3937 store_register (regcache
, regno
);
3939 #endif /* HAVE_LINUX_USRREGS */
3943 #ifdef HAVE_LINUX_REGSETS
3946 regsets_fetch_inferior_registers (struct regcache
*regcache
)
3948 struct regset_info
*regset
;
3949 int saw_general_regs
= 0;
3953 regset
= target_regsets
;
3955 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3956 while (regset
->size
>= 0)
3961 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
3967 buf
= xmalloc (regset
->size
);
3969 nt_type
= regset
->nt_type
;
3973 iov
.iov_len
= regset
->size
;
3974 data
= (void *) &iov
;
3980 res
= ptrace (regset
->get_request
, pid
, nt_type
, data
);
3982 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
3988 /* If we get EIO on a regset, do not try it again for
3990 disabled_regsets
[regset
- target_regsets
] = 1;
3997 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4002 else if (regset
->type
== GENERAL_REGS
)
4003 saw_general_regs
= 1;
4004 regset
->store_function (regcache
, buf
);
4008 if (saw_general_regs
)
4015 regsets_store_inferior_registers (struct regcache
*regcache
)
4017 struct regset_info
*regset
;
4018 int saw_general_regs
= 0;
4022 regset
= target_regsets
;
4024 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4025 while (regset
->size
>= 0)
4030 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
4036 buf
= xmalloc (regset
->size
);
4038 /* First fill the buffer with the current register set contents,
4039 in case there are any items in the kernel's regset that are
4040 not in gdbserver's regcache. */
4042 nt_type
= regset
->nt_type
;
4046 iov
.iov_len
= regset
->size
;
4047 data
= (void *) &iov
;
4053 res
= ptrace (regset
->get_request
, pid
, nt_type
, data
);
4055 res
= ptrace (regset
->get_request
, pid
, &iov
, data
);
4060 /* Then overlay our cached registers on that. */
4061 regset
->fill_function (regcache
, buf
);
4063 /* Only now do we write the register set. */
4065 res
= ptrace (regset
->set_request
, pid
, nt_type
, data
);
4067 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4075 /* If we get EIO on a regset, do not try it again for
4077 disabled_regsets
[regset
- target_regsets
] = 1;
4081 else if (errno
== ESRCH
)
4083 /* At this point, ESRCH should mean the process is
4084 already gone, in which case we simply ignore attempts
4085 to change its registers. See also the related
4086 comment in linux_resume_one_lwp. */
4092 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4095 else if (regset
->type
== GENERAL_REGS
)
4096 saw_general_regs
= 1;
4100 if (saw_general_regs
)
4107 #endif /* HAVE_LINUX_REGSETS */
4111 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4113 #ifdef HAVE_LINUX_REGSETS
4114 if (regsets_fetch_inferior_registers (regcache
) == 0)
4117 #ifdef HAVE_LINUX_USRREGS
4118 usr_fetch_inferior_registers (regcache
, regno
);
4123 linux_store_registers (struct regcache
*regcache
, int regno
)
4125 #ifdef HAVE_LINUX_REGSETS
4126 if (regsets_store_inferior_registers (regcache
) == 0)
4129 #ifdef HAVE_LINUX_USRREGS
4130 usr_store_inferior_registers (regcache
, regno
);
4135 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4136 to debugger memory starting at MYADDR. */
4139 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4142 /* Round starting address down to longword boundary. */
4143 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4144 /* Round ending address up; get number of longwords that makes. */
4146 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4147 / sizeof (PTRACE_XFER_TYPE
);
4148 /* Allocate buffer of that many longwords. */
4149 register PTRACE_XFER_TYPE
*buffer
4150 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4153 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4155 /* Try using /proc. Don't bother for one word. */
4156 if (len
>= 3 * sizeof (long))
4158 /* We could keep this file open and cache it - possibly one per
4159 thread. That requires some juggling, but is even faster. */
4160 sprintf (filename
, "/proc/%d/mem", pid
);
4161 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4165 /* If pread64 is available, use it. It's faster if the kernel
4166 supports it (only one syscall), and it's 64-bit safe even on
4167 32-bit platforms (for instance, SPARC debugging a SPARC64
4170 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
4172 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, myaddr
, len
) != len
)
4184 /* Read all the longwords */
4185 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4188 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4189 about coercing an 8 byte integer to a 4 byte pointer. */
4190 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4191 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4196 /* Copy appropriate bytes out of the buffer. */
4198 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4204 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4205 memory at MEMADDR. On failure (cannot write to the inferior)
4206 returns the value of errno. */
4209 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4212 /* Round starting address down to longword boundary. */
4213 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4214 /* Round ending address up; get number of longwords that makes. */
4216 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4217 / sizeof (PTRACE_XFER_TYPE
);
4219 /* Allocate buffer of that many longwords. */
4220 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4221 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4223 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4227 /* Dump up to four bytes. */
4228 unsigned int val
= * (unsigned int *) myaddr
;
4234 val
= val
& 0xffffff;
4235 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4236 val
, (long)memaddr
);
4239 /* Fill start and end extra bytes of buffer with existing memory data. */
4242 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4243 about coercing an 8 byte integer to a 4 byte pointer. */
4244 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4245 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4253 = ptrace (PTRACE_PEEKTEXT
, pid
,
4254 /* Coerce to a uintptr_t first to avoid potential gcc warning
4255 about coercing an 8 byte integer to a 4 byte pointer. */
4256 (PTRACE_ARG3_TYPE
) (uintptr_t) (addr
+ (count
- 1)
4257 * sizeof (PTRACE_XFER_TYPE
)),
4263 /* Copy data to be written over corresponding part of buffer. */
4265 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4268 /* Write the entire buffer. */
4270 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4273 ptrace (PTRACE_POKETEXT
, pid
,
4274 /* Coerce to a uintptr_t first to avoid potential gcc warning
4275 about coercing an 8 byte integer to a 4 byte pointer. */
4276 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
4277 (PTRACE_ARG4_TYPE
) buffer
[i
]);
4285 /* Non-zero if the kernel supports PTRACE_O_TRACEFORK. */
4286 static int linux_supports_tracefork_flag
;
4289 linux_enable_event_reporting (int pid
)
4291 if (!linux_supports_tracefork_flag
)
4294 ptrace (PTRACE_SETOPTIONS
, pid
, 0, (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
4297 /* Helper functions for linux_test_for_tracefork, called via clone (). */
4300 linux_tracefork_grandchild (void *arg
)
4305 #define STACK_SIZE 4096
4308 linux_tracefork_child (void *arg
)
4310 ptrace (PTRACE_TRACEME
, 0, 0, 0);
4311 kill (getpid (), SIGSTOP
);
4313 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4316 linux_tracefork_grandchild (NULL
);
4318 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4321 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
4322 CLONE_VM
| SIGCHLD
, NULL
);
4324 clone (linux_tracefork_grandchild
, (char *) arg
+ STACK_SIZE
,
4325 CLONE_VM
| SIGCHLD
, NULL
);
4328 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4333 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
4334 sure that we can enable the option, and that it had the desired
4338 linux_test_for_tracefork (void)
4340 int child_pid
, ret
, status
;
4342 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4343 char *stack
= xmalloc (STACK_SIZE
* 4);
4344 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4346 linux_supports_tracefork_flag
= 0;
4348 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4350 child_pid
= fork ();
4352 linux_tracefork_child (NULL
);
4354 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4356 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
4358 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
4359 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4360 #else /* !__ia64__ */
4361 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
4362 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4363 #endif /* !__ia64__ */
4365 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4367 if (child_pid
== -1)
4368 perror_with_name ("clone");
4370 ret
= my_waitpid (child_pid
, &status
, 0);
4372 perror_with_name ("waitpid");
4373 else if (ret
!= child_pid
)
4374 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
4375 if (! WIFSTOPPED (status
))
4376 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
4378 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
4379 (PTRACE_ARG4_TYPE
) PTRACE_O_TRACEFORK
);
4382 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4385 warning ("linux_test_for_tracefork: failed to kill child");
4389 ret
= my_waitpid (child_pid
, &status
, 0);
4390 if (ret
!= child_pid
)
4391 warning ("linux_test_for_tracefork: failed to wait for killed child");
4392 else if (!WIFSIGNALED (status
))
4393 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
4394 "killed child", status
);
4399 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
4401 warning ("linux_test_for_tracefork: failed to resume child");
4403 ret
= my_waitpid (child_pid
, &status
, 0);
4405 if (ret
== child_pid
&& WIFSTOPPED (status
)
4406 && status
>> 16 == PTRACE_EVENT_FORK
)
4409 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
4410 if (ret
== 0 && second_pid
!= 0)
4414 linux_supports_tracefork_flag
= 1;
4415 my_waitpid (second_pid
, &second_status
, 0);
4416 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
4418 warning ("linux_test_for_tracefork: failed to kill second child");
4419 my_waitpid (second_pid
, &status
, 0);
4423 warning ("linux_test_for_tracefork: unexpected result from waitpid "
4424 "(%d, status 0x%x)", ret
, status
);
4428 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4430 warning ("linux_test_for_tracefork: failed to kill child");
4431 my_waitpid (child_pid
, &status
, 0);
4433 while (WIFSTOPPED (status
));
4435 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4437 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4442 linux_look_up_symbols (void)
4444 #ifdef USE_THREAD_DB
4445 struct process_info
*proc
= current_process ();
4447 if (proc
->private->thread_db
!= NULL
)
4450 /* If the kernel supports tracing forks then it also supports tracing
4451 clones, and then we don't need to use the magic thread event breakpoint
4452 to learn about threads. */
4453 thread_db_init (!linux_supports_tracefork_flag
);
4458 linux_request_interrupt (void)
4460 extern unsigned long signal_pid
;
4462 if (!ptid_equal (cont_thread
, null_ptid
)
4463 && !ptid_equal (cont_thread
, minus_one_ptid
))
4465 struct lwp_info
*lwp
;
4468 lwp
= get_thread_lwp (current_inferior
);
4469 lwpid
= lwpid_of (lwp
);
4470 kill_lwp (lwpid
, SIGINT
);
4473 kill_lwp (signal_pid
, SIGINT
);
4476 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4477 to debugger memory starting at MYADDR. */
4480 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4482 char filename
[PATH_MAX
];
4484 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4486 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4488 fd
= open (filename
, O_RDONLY
);
4492 if (offset
!= (CORE_ADDR
) 0
4493 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4496 n
= read (fd
, myaddr
, len
);
4503 /* These breakpoint and watchpoint related wrapper functions simply
4504 pass on the function call if the target has registered a
4505 corresponding function. */
4508 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
4510 if (the_low_target
.insert_point
!= NULL
)
4511 return the_low_target
.insert_point (type
, addr
, len
);
4513 /* Unsupported (see target.h). */
4518 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
4520 if (the_low_target
.remove_point
!= NULL
)
4521 return the_low_target
.remove_point (type
, addr
, len
);
4523 /* Unsupported (see target.h). */
4528 linux_stopped_by_watchpoint (void)
4530 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4532 return lwp
->stopped_by_watchpoint
;
4536 linux_stopped_data_address (void)
4538 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4540 return lwp
->stopped_data_address
;
4543 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4544 #if defined(__mcoldfire__)
4545 /* These should really be defined in the kernel's ptrace.h header. */
4546 #define PT_TEXT_ADDR 49*4
4547 #define PT_DATA_ADDR 50*4
4548 #define PT_TEXT_END_ADDR 51*4
4550 #define PT_TEXT_ADDR 220
4551 #define PT_TEXT_END_ADDR 224
4552 #define PT_DATA_ADDR 228
4553 #elif defined(__TMS320C6X__)
4554 #define PT_TEXT_ADDR (0x10000*4)
4555 #define PT_DATA_ADDR (0x10004*4)
4556 #define PT_TEXT_END_ADDR (0x10008*4)
4559 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4560 to tell gdb about. */
4563 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
4565 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
4566 unsigned long text
, text_end
, data
;
4567 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4571 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
4572 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
4573 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
4577 /* Both text and data offsets produced at compile-time (and so
4578 used by gdb) are relative to the beginning of the program,
4579 with the data segment immediately following the text segment.
4580 However, the actual runtime layout in memory may put the data
4581 somewhere else, so when we send gdb a data base-address, we
4582 use the real data base address and subtract the compile-time
4583 data base-address from it (which is just the length of the
4584 text segment). BSS immediately follows data in both
4587 *data_p
= data
- (text_end
- text
);
4597 linux_qxfer_osdata (const char *annex
,
4598 unsigned char *readbuf
, unsigned const char *writebuf
,
4599 CORE_ADDR offset
, int len
)
4601 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
4604 /* Convert a native/host siginfo object, into/from the siginfo in the
4605 layout of the inferiors' architecture. */
4608 siginfo_fixup (struct siginfo
*siginfo
, void *inf_siginfo
, int direction
)
4612 if (the_low_target
.siginfo_fixup
!= NULL
)
4613 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4615 /* If there was no callback, or the callback didn't do anything,
4616 then just do a straight memcpy. */
4620 memcpy (siginfo
, inf_siginfo
, sizeof (struct siginfo
));
4622 memcpy (inf_siginfo
, siginfo
, sizeof (struct siginfo
));
4627 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
4628 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
4631 struct siginfo siginfo
;
4632 char inf_siginfo
[sizeof (struct siginfo
)];
4634 if (current_inferior
== NULL
)
4637 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4640 fprintf (stderr
, "%s siginfo for lwp %d.\n",
4641 readbuf
!= NULL
? "Reading" : "Writing",
4644 if (offset
>= sizeof (siginfo
))
4647 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
4650 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4651 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4652 inferior with a 64-bit GDBSERVER should look the same as debugging it
4653 with a 32-bit GDBSERVER, we need to convert it. */
4654 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4656 if (offset
+ len
> sizeof (siginfo
))
4657 len
= sizeof (siginfo
) - offset
;
4659 if (readbuf
!= NULL
)
4660 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4663 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4665 /* Convert back to ptrace layout before flushing it out. */
4666 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4668 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
4675 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4676 so we notice when children change state; as the handler for the
4677 sigsuspend in my_waitpid. */
4680 sigchld_handler (int signo
)
4682 int old_errno
= errno
;
4688 /* fprintf is not async-signal-safe, so call write
4690 if (write (2, "sigchld_handler\n",
4691 sizeof ("sigchld_handler\n") - 1) < 0)
4692 break; /* just ignore */
4696 if (target_is_async_p ())
4697 async_file_mark (); /* trigger a linux_wait */
4703 linux_supports_non_stop (void)
4709 linux_async (int enable
)
4711 int previous
= (linux_event_pipe
[0] != -1);
4714 fprintf (stderr
, "linux_async (%d), previous=%d\n",
4717 if (previous
!= enable
)
4720 sigemptyset (&mask
);
4721 sigaddset (&mask
, SIGCHLD
);
4723 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
4727 if (pipe (linux_event_pipe
) == -1)
4728 fatal ("creating event pipe failed.");
4730 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
4731 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
4733 /* Register the event loop handler. */
4734 add_file_handler (linux_event_pipe
[0],
4735 handle_target_event
, NULL
);
4737 /* Always trigger a linux_wait. */
4742 delete_file_handler (linux_event_pipe
[0]);
4744 close (linux_event_pipe
[0]);
4745 close (linux_event_pipe
[1]);
4746 linux_event_pipe
[0] = -1;
4747 linux_event_pipe
[1] = -1;
4750 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
4757 linux_start_non_stop (int nonstop
)
4759 /* Register or unregister from event-loop accordingly. */
4760 linux_async (nonstop
);
4765 linux_supports_multi_process (void)
4771 linux_supports_disable_randomization (void)
4773 #ifdef HAVE_PERSONALITY
4780 /* Enumerate spufs IDs for process PID. */
4782 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
4788 struct dirent
*entry
;
4790 sprintf (path
, "/proc/%ld/fd", pid
);
4791 dir
= opendir (path
);
4796 while ((entry
= readdir (dir
)) != NULL
)
4802 fd
= atoi (entry
->d_name
);
4806 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
4807 if (stat (path
, &st
) != 0)
4809 if (!S_ISDIR (st
.st_mode
))
4812 if (statfs (path
, &stfs
) != 0)
4814 if (stfs
.f_type
!= SPUFS_MAGIC
)
4817 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
4819 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
4829 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
4830 object type, using the /proc file system. */
4832 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
4833 unsigned const char *writebuf
,
4834 CORE_ADDR offset
, int len
)
4836 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
4841 if (!writebuf
&& !readbuf
)
4849 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
4852 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
4853 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
4858 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4865 ret
= write (fd
, writebuf
, (size_t) len
);
4867 ret
= read (fd
, readbuf
, (size_t) len
);
4873 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
4874 struct target_loadseg
4876 /* Core address to which the segment is mapped. */
4878 /* VMA recorded in the program header. */
4880 /* Size of this segment in memory. */
4884 # if defined PT_GETDSBT
4885 struct target_loadmap
4887 /* Protocol version number, must be zero. */
4889 /* Pointer to the DSBT table, its size, and the DSBT index. */
4890 unsigned *dsbt_table
;
4891 unsigned dsbt_size
, dsbt_index
;
4892 /* Number of segments in this map. */
4894 /* The actual memory map. */
4895 struct target_loadseg segs
[/*nsegs*/];
4897 # define LINUX_LOADMAP PT_GETDSBT
4898 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
4899 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
4901 struct target_loadmap
4903 /* Protocol version number, must be zero. */
4905 /* Number of segments in this map. */
4907 /* The actual memory map. */
4908 struct target_loadseg segs
[/*nsegs*/];
4910 # define LINUX_LOADMAP PTRACE_GETFDPIC
4911 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
4912 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
4916 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
4917 unsigned char *myaddr
, unsigned int len
)
4919 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4921 struct target_loadmap
*data
= NULL
;
4922 unsigned int actual_length
, copy_length
;
4924 if (strcmp (annex
, "exec") == 0)
4925 addr
= (int) LINUX_LOADMAP_EXEC
;
4926 else if (strcmp (annex
, "interp") == 0)
4927 addr
= (int) LINUX_LOADMAP_INTERP
;
4931 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
4937 actual_length
= sizeof (struct target_loadmap
)
4938 + sizeof (struct target_loadseg
) * data
->nsegs
;
4940 if (offset
< 0 || offset
> actual_length
)
4943 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
4944 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
4948 # define linux_read_loadmap NULL
4949 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
4952 linux_process_qsupported (const char *query
)
4954 if (the_low_target
.process_qsupported
!= NULL
)
4955 the_low_target
.process_qsupported (query
);
4959 linux_supports_tracepoints (void)
4961 if (*the_low_target
.supports_tracepoints
== NULL
)
4964 return (*the_low_target
.supports_tracepoints
) ();
4968 linux_read_pc (struct regcache
*regcache
)
4970 if (the_low_target
.get_pc
== NULL
)
4973 return (*the_low_target
.get_pc
) (regcache
);
4977 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
4979 gdb_assert (the_low_target
.set_pc
!= NULL
);
4981 (*the_low_target
.set_pc
) (regcache
, pc
);
4985 linux_thread_stopped (struct thread_info
*thread
)
4987 return get_thread_lwp (thread
)->stopped
;
4990 /* This exposes stop-all-threads functionality to other modules. */
4993 linux_pause_all (int freeze
)
4995 stop_all_lwps (freeze
, NULL
);
4998 /* This exposes unstop-all-threads functionality to other gdbserver
5002 linux_unpause_all (int unfreeze
)
5004 unstop_all_lwps (unfreeze
, NULL
);
5008 linux_prepare_to_access_memory (void)
5010 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5013 linux_pause_all (1);
5018 linux_done_accessing_memory (void)
5020 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5023 linux_unpause_all (1);
5027 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5028 CORE_ADDR collector
,
5031 CORE_ADDR
*jump_entry
,
5032 CORE_ADDR
*trampoline
,
5033 ULONGEST
*trampoline_size
,
5034 unsigned char *jjump_pad_insn
,
5035 ULONGEST
*jjump_pad_insn_size
,
5036 CORE_ADDR
*adjusted_insn_addr
,
5037 CORE_ADDR
*adjusted_insn_addr_end
,
5040 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5041 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5042 jump_entry
, trampoline
, trampoline_size
,
5043 jjump_pad_insn
, jjump_pad_insn_size
,
5044 adjusted_insn_addr
, adjusted_insn_addr_end
,
5048 static struct emit_ops
*
5049 linux_emit_ops (void)
5051 if (the_low_target
.emit_ops
!= NULL
)
5052 return (*the_low_target
.emit_ops
) ();
5058 linux_get_min_fast_tracepoint_insn_len (void)
5060 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5063 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5066 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5067 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5069 char filename
[PATH_MAX
];
5071 const int auxv_size
= is_elf64
5072 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5073 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5075 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5077 fd
= open (filename
, O_RDONLY
);
5083 while (read (fd
, buf
, auxv_size
) == auxv_size
5084 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5088 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5090 switch (aux
->a_type
)
5093 *phdr_memaddr
= aux
->a_un
.a_val
;
5096 *num_phdr
= aux
->a_un
.a_val
;
5102 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5104 switch (aux
->a_type
)
5107 *phdr_memaddr
= aux
->a_un
.a_val
;
5110 *num_phdr
= aux
->a_un
.a_val
;
5118 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5120 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5121 "phdr_memaddr = %ld, phdr_num = %d",
5122 (long) *phdr_memaddr
, *num_phdr
);
5129 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5132 get_dynamic (const int pid
, const int is_elf64
)
5134 CORE_ADDR phdr_memaddr
, relocation
;
5136 unsigned char *phdr_buf
;
5137 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5139 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5142 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5143 phdr_buf
= alloca (num_phdr
* phdr_size
);
5145 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5148 /* Compute relocation: it is expected to be 0 for "regular" executables,
5149 non-zero for PIE ones. */
5151 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5154 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5156 if (p
->p_type
== PT_PHDR
)
5157 relocation
= phdr_memaddr
- p
->p_vaddr
;
5161 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5163 if (p
->p_type
== PT_PHDR
)
5164 relocation
= phdr_memaddr
- p
->p_vaddr
;
5167 if (relocation
== -1)
5169 warning ("Unexpected missing PT_PHDR");
5173 for (i
= 0; i
< num_phdr
; i
++)
5177 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5179 if (p
->p_type
== PT_DYNAMIC
)
5180 return p
->p_vaddr
+ relocation
;
5184 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5186 if (p
->p_type
== PT_DYNAMIC
)
5187 return p
->p_vaddr
+ relocation
;
5194 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5195 can be 0 if the inferior does not yet have the library list initialized. */
5198 get_r_debug (const int pid
, const int is_elf64
)
5200 CORE_ADDR dynamic_memaddr
;
5201 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5202 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5204 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5205 if (dynamic_memaddr
== 0)
5206 return (CORE_ADDR
) -1;
5208 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5212 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5214 if (dyn
->d_tag
== DT_DEBUG
)
5215 return dyn
->d_un
.d_val
;
5217 if (dyn
->d_tag
== DT_NULL
)
5222 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5224 if (dyn
->d_tag
== DT_DEBUG
)
5225 return dyn
->d_un
.d_val
;
5227 if (dyn
->d_tag
== DT_NULL
)
5231 dynamic_memaddr
+= dyn_size
;
5234 return (CORE_ADDR
) -1;
5237 /* Read one pointer from MEMADDR in the inferior. */
5240 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5243 return linux_read_memory (memaddr
, (unsigned char *) ptr
, ptr_size
);
5246 struct link_map_offsets
5248 /* Offset and size of r_debug.r_version. */
5249 int r_version_offset
;
5251 /* Offset and size of r_debug.r_map. */
5254 /* Offset to l_addr field in struct link_map. */
5257 /* Offset to l_name field in struct link_map. */
5260 /* Offset to l_ld field in struct link_map. */
5263 /* Offset to l_next field in struct link_map. */
5266 /* Offset to l_prev field in struct link_map. */
5270 /* Construct qXfer:libraries:read reply. */
5273 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5274 unsigned const char *writebuf
,
5275 CORE_ADDR offset
, int len
)
5278 unsigned document_len
;
5279 struct process_info_private
*const priv
= current_process ()->private;
5280 char filename
[PATH_MAX
];
5283 static const struct link_map_offsets lmo_32bit_offsets
=
5285 0, /* r_version offset. */
5286 4, /* r_debug.r_map offset. */
5287 0, /* l_addr offset in link_map. */
5288 4, /* l_name offset in link_map. */
5289 8, /* l_ld offset in link_map. */
5290 12, /* l_next offset in link_map. */
5291 16 /* l_prev offset in link_map. */
5294 static const struct link_map_offsets lmo_64bit_offsets
=
5296 0, /* r_version offset. */
5297 8, /* r_debug.r_map offset. */
5298 0, /* l_addr offset in link_map. */
5299 8, /* l_name offset in link_map. */
5300 16, /* l_ld offset in link_map. */
5301 24, /* l_next offset in link_map. */
5302 32 /* l_prev offset in link_map. */
5304 const struct link_map_offsets
*lmo
;
5306 if (writebuf
!= NULL
)
5308 if (readbuf
== NULL
)
5311 pid
= lwpid_of (get_thread_lwp (current_inferior
));
5312 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5313 is_elf64
= elf_64_file_p (filename
);
5314 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5316 if (priv
->r_debug
== 0)
5317 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5319 if (priv
->r_debug
== (CORE_ADDR
) -1 || priv
->r_debug
== 0)
5321 document
= xstrdup ("<library-list-svr4 version=\"1.0\"/>\n");
5325 int allocated
= 1024;
5327 const int ptr_size
= is_elf64
? 8 : 4;
5328 CORE_ADDR lm_addr
, lm_prev
, l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5329 int r_version
, header_done
= 0;
5331 document
= xmalloc (allocated
);
5332 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5333 p
= document
+ strlen (document
);
5336 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5337 (unsigned char *) &r_version
,
5338 sizeof (r_version
)) != 0
5341 warning ("unexpected r_debug version %d", r_version
);
5345 if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5346 &lm_addr
, ptr_size
) != 0)
5348 warning ("unable to read r_map from 0x%lx",
5349 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5354 while (read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5355 &l_name
, ptr_size
) == 0
5356 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5357 &l_addr
, ptr_size
) == 0
5358 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5359 &l_ld
, ptr_size
) == 0
5360 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5361 &l_prev
, ptr_size
) == 0
5362 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5363 &l_next
, ptr_size
) == 0)
5365 unsigned char libname
[PATH_MAX
];
5367 if (lm_prev
!= l_prev
)
5369 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5370 (long) lm_prev
, (long) l_prev
);
5374 /* Not checking for error because reading may stop before
5375 we've got PATH_MAX worth of characters. */
5377 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5378 libname
[sizeof (libname
) - 1] = '\0';
5379 if (libname
[0] != '\0')
5381 /* 6x the size for xml_escape_text below. */
5382 size_t len
= 6 * strlen ((char *) libname
);
5387 /* Terminate `<library-list-svr4'. */
5392 while (allocated
< p
- document
+ len
+ 200)
5394 /* Expand to guarantee sufficient storage. */
5395 uintptr_t document_len
= p
- document
;
5397 document
= xrealloc (document
, 2 * allocated
);
5399 p
= document
+ document_len
;
5402 name
= xml_escape_text ((char *) libname
);
5403 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
5404 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5405 name
, (unsigned long) lm_addr
,
5406 (unsigned long) l_addr
, (unsigned long) l_ld
);
5409 else if (lm_prev
== 0)
5411 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5422 strcpy (p
, "</library-list-svr4>");
5425 document_len
= strlen (document
);
5426 if (offset
< document_len
)
5427 document_len
-= offset
;
5430 if (len
> document_len
)
5433 memcpy (readbuf
, document
+ offset
, len
);
5439 static struct target_ops linux_target_ops
= {
5440 linux_create_inferior
,
5449 linux_fetch_registers
,
5450 linux_store_registers
,
5451 linux_prepare_to_access_memory
,
5452 linux_done_accessing_memory
,
5455 linux_look_up_symbols
,
5456 linux_request_interrupt
,
5460 linux_stopped_by_watchpoint
,
5461 linux_stopped_data_address
,
5462 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
5467 #ifdef USE_THREAD_DB
5468 thread_db_get_tls_address
,
5473 hostio_last_error_from_errno
,
5476 linux_supports_non_stop
,
5478 linux_start_non_stop
,
5479 linux_supports_multi_process
,
5480 #ifdef USE_THREAD_DB
5481 thread_db_handle_monitor_command
,
5485 linux_common_core_of_thread
,
5487 linux_process_qsupported
,
5488 linux_supports_tracepoints
,
5491 linux_thread_stopped
,
5495 linux_cancel_breakpoints
,
5496 linux_stabilize_threads
,
5497 linux_install_fast_tracepoint_jump_pad
,
5499 linux_supports_disable_randomization
,
5500 linux_get_min_fast_tracepoint_insn_len
,
5501 linux_qxfer_libraries_svr4
,
5505 linux_init_signals ()
5507 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5508 to find what the cancel signal actually is. */
5509 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
5510 signal (__SIGRTMIN
+1, SIG_IGN
);
5515 initialize_low (void)
5517 struct sigaction sigchld_action
;
5518 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
5519 set_target_ops (&linux_target_ops
);
5520 set_breakpoint_data (the_low_target
.breakpoint
,
5521 the_low_target
.breakpoint_len
);
5522 linux_init_signals ();
5523 linux_test_for_tracefork ();
5524 #ifdef HAVE_LINUX_REGSETS
5525 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
5527 disabled_regsets
= xmalloc (num_regsets
);
5530 sigchld_action
.sa_handler
= sigchld_handler
;
5531 sigemptyset (&sigchld_action
.sa_mask
);
5532 sigchld_action
.sa_flags
= SA_RESTART
;
5533 sigaction (SIGCHLD
, &sigchld_action
, NULL
);