1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2013 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "linux-osdata.h"
26 #include <sys/param.h>
27 #include <sys/ptrace.h>
28 #include "linux-ptrace.h"
29 #include "linux-procfs.h"
31 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
47 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
48 then ELFMAG0 will have been defined. If it didn't get included by
49 gdb_proc_service.h then including it will likely introduce a duplicate
50 definition of elf_fpregset_t. */
55 #define SPUFS_MAGIC 0x23c9b64e
58 #ifdef HAVE_PERSONALITY
59 # include <sys/personality.h>
60 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
61 # define ADDR_NO_RANDOMIZE 0x0040000
70 #define W_STOPCODE(sig) ((sig) << 8 | 0x7f)
73 /* This is the kernel's hard limit. Not to be confused with
80 #if !(defined(__UCLIBC_HAS_MMU__) || defined(__ARCH_HAS_MMU__))
81 /* PTRACE_TEXT_ADDR and friends. */
82 #include <asm/ptrace.h>
87 #ifndef HAVE_ELF32_AUXV_T
88 /* Copied from glibc's elf.h. */
91 uint32_t a_type
; /* Entry type */
94 uint32_t a_val
; /* Integer value */
95 /* We use to have pointer elements added here. We cannot do that,
96 though, since it does not work when using 32-bit definitions
97 on 64-bit platforms and vice versa. */
102 #ifndef HAVE_ELF64_AUXV_T
103 /* Copied from glibc's elf.h. */
106 uint64_t a_type
; /* Entry type */
109 uint64_t a_val
; /* Integer value */
110 /* We use to have pointer elements added here. We cannot do that,
111 though, since it does not work when using 32-bit definitions
112 on 64-bit platforms and vice versa. */
117 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
118 representation of the thread ID.
120 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
121 the same as the LWP ID.
123 ``all_processes'' is keyed by the "overall process ID", which
124 GNU/Linux calls tgid, "thread group ID". */
126 struct inferior_list all_lwps
;
128 /* A list of all unknown processes which receive stop signals. Some
129 other process will presumably claim each of these as forked
130 children momentarily. */
132 struct simple_pid_list
134 /* The process ID. */
137 /* The status as reported by waitpid. */
141 struct simple_pid_list
*next
;
143 struct simple_pid_list
*stopped_pids
;
145 /* Trivial list manipulation functions to keep track of a list of new
146 stopped processes. */
149 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
151 struct simple_pid_list
*new_pid
= xmalloc (sizeof (struct simple_pid_list
));
154 new_pid
->status
= status
;
155 new_pid
->next
= *listp
;
160 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
162 struct simple_pid_list
**p
;
164 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
165 if ((*p
)->pid
== pid
)
167 struct simple_pid_list
*next
= (*p
)->next
;
169 *statusp
= (*p
)->status
;
177 enum stopping_threads_kind
179 /* Not stopping threads presently. */
180 NOT_STOPPING_THREADS
,
182 /* Stopping threads. */
185 /* Stopping and suspending threads. */
186 STOPPING_AND_SUSPENDING_THREADS
189 /* This is set while stop_all_lwps is in effect. */
190 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
192 /* FIXME make into a target method? */
193 int using_threads
= 1;
195 /* True if we're presently stabilizing threads (moving them out of
197 static int stabilizing_threads
;
199 /* This flag is true iff we've just created or attached to our first
200 inferior but it has not stopped yet. As soon as it does, we need
201 to call the low target's arch_setup callback. Doing this only on
202 the first inferior avoids reinializing the architecture on every
203 inferior, and avoids messing with the register caches of the
204 already running inferiors. NOTE: this assumes all inferiors under
205 control of gdbserver have the same architecture. */
206 static int new_inferior
;
208 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
209 int step
, int signal
, siginfo_t
*info
);
210 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
211 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
212 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
213 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
214 static void *add_lwp (ptid_t ptid
);
215 static int linux_stopped_by_watchpoint (void);
216 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
217 static void proceed_all_lwps (void);
218 static int finish_step_over (struct lwp_info
*lwp
);
219 static CORE_ADDR
get_stop_pc (struct lwp_info
*lwp
);
220 static int kill_lwp (unsigned long lwpid
, int signo
);
221 static void linux_enable_event_reporting (int pid
);
223 /* True if the low target can hardware single-step. Such targets
224 don't need a BREAKPOINT_REINSERT_ADDR callback. */
227 can_hardware_single_step (void)
229 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
232 /* True if the low target supports memory breakpoints. If so, we'll
233 have a GET_PC implementation. */
236 supports_breakpoints (void)
238 return (the_low_target
.get_pc
!= NULL
);
241 /* Returns true if this target can support fast tracepoints. This
242 does not mean that the in-process agent has been loaded in the
246 supports_fast_tracepoints (void)
248 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
251 struct pending_signals
255 struct pending_signals
*prev
;
258 #ifdef HAVE_LINUX_REGSETS
259 static char *disabled_regsets
;
260 static int num_regsets
;
263 /* The read/write ends of the pipe registered as waitable file in the
265 static int linux_event_pipe
[2] = { -1, -1 };
267 /* True if we're currently in async mode. */
268 #define target_is_async_p() (linux_event_pipe[0] != -1)
270 static void send_sigstop (struct lwp_info
*lwp
);
271 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
273 /* Return non-zero if HEADER is a 64-bit ELF file. */
276 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
278 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
279 && header
->e_ident
[EI_MAG1
] == ELFMAG1
280 && header
->e_ident
[EI_MAG2
] == ELFMAG2
281 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
283 *machine
= header
->e_machine
;
284 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
291 /* Return non-zero if FILE is a 64-bit ELF file,
292 zero if the file is not a 64-bit ELF file,
293 and -1 if the file is not accessible or doesn't exist. */
296 elf_64_file_p (const char *file
, unsigned int *machine
)
301 fd
= open (file
, O_RDONLY
);
305 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
312 return elf_64_header_p (&header
, machine
);
315 /* Accepts an integer PID; Returns true if the executable PID is
316 running is a 64-bit ELF file.. */
319 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
321 char file
[MAXPATHLEN
];
323 sprintf (file
, "/proc/%d/exe", pid
);
324 return elf_64_file_p (file
, machine
);
328 delete_lwp (struct lwp_info
*lwp
)
330 remove_thread (get_lwp_thread (lwp
));
331 remove_inferior (&all_lwps
, &lwp
->head
);
332 free (lwp
->arch_private
);
336 /* Add a process to the common process list, and set its private
339 static struct process_info
*
340 linux_add_process (int pid
, int attached
)
342 struct process_info
*proc
;
344 /* Is this the first process? If so, then set the arch. */
345 if (all_processes
.head
== NULL
)
348 proc
= add_process (pid
, attached
);
349 proc
->private = xcalloc (1, sizeof (*proc
->private));
351 if (the_low_target
.new_process
!= NULL
)
352 proc
->private->arch_private
= the_low_target
.new_process ();
357 /* Wrapper function for waitpid which handles EINTR, and emulates
358 __WALL for systems where that is not available. */
361 my_waitpid (int pid
, int *status
, int flags
)
366 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
370 sigset_t block_mask
, org_mask
, wake_mask
;
373 wnohang
= (flags
& WNOHANG
) != 0;
374 flags
&= ~(__WALL
| __WCLONE
);
377 /* Block all signals while here. This avoids knowing about
378 LinuxThread's signals. */
379 sigfillset (&block_mask
);
380 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
382 /* ... except during the sigsuspend below. */
383 sigemptyset (&wake_mask
);
387 /* Since all signals are blocked, there's no need to check
389 ret
= waitpid (pid
, status
, flags
);
392 if (ret
== -1 && out_errno
!= ECHILD
)
397 if (flags
& __WCLONE
)
399 /* We've tried both flavors now. If WNOHANG is set,
400 there's nothing else to do, just bail out. */
405 fprintf (stderr
, "blocking\n");
407 /* Block waiting for signals. */
408 sigsuspend (&wake_mask
);
414 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
419 ret
= waitpid (pid
, status
, flags
);
420 while (ret
== -1 && errno
== EINTR
);
425 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
426 pid
, flags
, status
? *status
: -1, ret
);
432 /* Handle a GNU/Linux extended wait response. If we see a clone
433 event, we need to add the new LWP to our list (and not report the
434 trap to higher layers). */
437 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
439 int event
= wstat
>> 16;
440 struct lwp_info
*new_lwp
;
442 if (event
== PTRACE_EVENT_CLONE
)
445 unsigned long new_pid
;
448 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), 0, &new_pid
);
450 /* If we haven't already seen the new PID stop, wait for it now. */
451 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
453 /* The new child has a pending SIGSTOP. We can't affect it until it
454 hits the SIGSTOP, but we're already attached. */
456 ret
= my_waitpid (new_pid
, &status
, __WALL
);
459 perror_with_name ("waiting for new child");
460 else if (ret
!= new_pid
)
461 warning ("wait returned unexpected PID %d", ret
);
462 else if (!WIFSTOPPED (status
))
463 warning ("wait returned unexpected status 0x%x", status
);
466 linux_enable_event_reporting (new_pid
);
468 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
469 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
470 add_thread (ptid
, new_lwp
);
472 /* Either we're going to immediately resume the new thread
473 or leave it stopped. linux_resume_one_lwp is a nop if it
474 thinks the thread is currently running, so set this first
475 before calling linux_resume_one_lwp. */
476 new_lwp
->stopped
= 1;
478 /* If we're suspending all threads, leave this one suspended
480 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
481 new_lwp
->suspended
= 1;
483 /* Normally we will get the pending SIGSTOP. But in some cases
484 we might get another signal delivered to the group first.
485 If we do get another signal, be sure not to lose it. */
486 if (WSTOPSIG (status
) == SIGSTOP
)
488 if (stopping_threads
!= NOT_STOPPING_THREADS
)
489 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
491 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
495 new_lwp
->stop_expected
= 1;
497 if (stopping_threads
!= NOT_STOPPING_THREADS
)
499 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
500 new_lwp
->status_pending_p
= 1;
501 new_lwp
->status_pending
= status
;
504 /* Pass the signal on. This is what GDB does - except
505 shouldn't we really report it instead? */
506 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
509 /* Always resume the current thread. If we are stopping
510 threads, it will have a pending SIGSTOP; we may as well
512 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
516 /* Return the PC as read from the regcache of LWP, without any
520 get_pc (struct lwp_info
*lwp
)
522 struct thread_info
*saved_inferior
;
523 struct regcache
*regcache
;
526 if (the_low_target
.get_pc
== NULL
)
529 saved_inferior
= current_inferior
;
530 current_inferior
= get_lwp_thread (lwp
);
532 regcache
= get_thread_regcache (current_inferior
, 1);
533 pc
= (*the_low_target
.get_pc
) (regcache
);
536 fprintf (stderr
, "pc is 0x%lx\n", (long) pc
);
538 current_inferior
= saved_inferior
;
542 /* This function should only be called if LWP got a SIGTRAP.
543 The SIGTRAP could mean several things.
545 On i386, where decr_pc_after_break is non-zero:
546 If we were single-stepping this process using PTRACE_SINGLESTEP,
547 we will get only the one SIGTRAP (even if the instruction we
548 stepped over was a breakpoint). The value of $eip will be the
550 If we continue the process using PTRACE_CONT, we will get a
551 SIGTRAP when we hit a breakpoint. The value of $eip will be
552 the instruction after the breakpoint (i.e. needs to be
553 decremented). If we report the SIGTRAP to GDB, we must also
554 report the undecremented PC. If we cancel the SIGTRAP, we
555 must resume at the decremented PC.
557 (Presumably, not yet tested) On a non-decr_pc_after_break machine
558 with hardware or kernel single-step:
559 If we single-step over a breakpoint instruction, our PC will
560 point at the following instruction. If we continue and hit a
561 breakpoint instruction, our PC will point at the breakpoint
565 get_stop_pc (struct lwp_info
*lwp
)
569 if (the_low_target
.get_pc
== NULL
)
572 stop_pc
= get_pc (lwp
);
574 if (WSTOPSIG (lwp
->last_status
) == SIGTRAP
576 && !lwp
->stopped_by_watchpoint
577 && lwp
->last_status
>> 16 == 0)
578 stop_pc
-= the_low_target
.decr_pc_after_break
;
581 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
587 add_lwp (ptid_t ptid
)
589 struct lwp_info
*lwp
;
591 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
592 memset (lwp
, 0, sizeof (*lwp
));
596 if (the_low_target
.new_thread
!= NULL
)
597 lwp
->arch_private
= the_low_target
.new_thread ();
599 add_inferior_to_list (&all_lwps
, &lwp
->head
);
604 /* Start an inferior process and returns its pid.
605 ALLARGS is a vector of program-name and args. */
608 linux_create_inferior (char *program
, char **allargs
)
610 #ifdef HAVE_PERSONALITY
611 int personality_orig
= 0, personality_set
= 0;
613 struct lwp_info
*new_lwp
;
617 #ifdef HAVE_PERSONALITY
618 if (disable_randomization
)
621 personality_orig
= personality (0xffffffff);
622 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
625 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
627 if (errno
!= 0 || (personality_set
628 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
629 warning ("Error disabling address space randomization: %s",
634 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
640 perror_with_name ("fork");
644 ptrace (PTRACE_TRACEME
, 0, 0, 0);
646 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
647 signal (__SIGRTMIN
+ 1, SIG_DFL
);
652 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
653 stdout to stderr so that inferior i/o doesn't corrupt the connection.
654 Also, redirect stdin to /dev/null. */
655 if (remote_connection_is_stdio ())
658 open ("/dev/null", O_RDONLY
);
660 if (write (2, "stdin/stdout redirected\n",
661 sizeof ("stdin/stdout redirected\n") - 1) < 0)
663 /* Errors ignored. */;
667 execv (program
, allargs
);
669 execvp (program
, allargs
);
671 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
677 #ifdef HAVE_PERSONALITY
681 personality (personality_orig
);
683 warning ("Error restoring address space randomization: %s",
688 linux_add_process (pid
, 0);
690 ptid
= ptid_build (pid
, pid
, 0);
691 new_lwp
= add_lwp (ptid
);
692 add_thread (ptid
, new_lwp
);
693 new_lwp
->must_set_ptrace_flags
= 1;
698 /* Attach to an inferior process. */
701 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
704 struct lwp_info
*new_lwp
;
706 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) != 0)
708 struct buffer buffer
;
712 /* If we fail to attach to an LWP, just warn. */
713 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
714 strerror (errno
), errno
);
719 /* If we fail to attach to a process, report an error. */
720 buffer_init (&buffer
);
721 linux_ptrace_attach_warnings (lwpid
, &buffer
);
722 buffer_grow_str0 (&buffer
, "");
723 error ("%sCannot attach to lwp %ld: %s (%d)", buffer_finish (&buffer
),
724 lwpid
, strerror (errno
), errno
);
728 /* If lwp is the tgid, we handle adding existing threads later.
729 Otherwise we just add lwp without bothering about any other
731 ptid
= ptid_build (lwpid
, lwpid
, 0);
734 /* Note that extracting the pid from the current inferior is
735 safe, since we're always called in the context of the same
736 process as this new thread. */
737 int pid
= pid_of (get_thread_lwp (current_inferior
));
738 ptid
= ptid_build (pid
, lwpid
, 0);
741 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
742 add_thread (ptid
, new_lwp
);
744 /* We need to wait for SIGSTOP before being able to make the next
745 ptrace call on this LWP. */
746 new_lwp
->must_set_ptrace_flags
= 1;
748 if (linux_proc_pid_is_stopped (lwpid
))
752 "Attached to a stopped process\n");
754 /* The process is definitely stopped. It is in a job control
755 stop, unless the kernel predates the TASK_STOPPED /
756 TASK_TRACED distinction, in which case it might be in a
757 ptrace stop. Make sure it is in a ptrace stop; from there we
758 can kill it, signal it, et cetera.
760 First make sure there is a pending SIGSTOP. Since we are
761 already attached, the process can not transition from stopped
762 to running without a PTRACE_CONT; so we know this signal will
763 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
764 probably already in the queue (unless this kernel is old
765 enough to use TASK_STOPPED for ptrace stops); but since
766 SIGSTOP is not an RT signal, it can only be queued once. */
767 kill_lwp (lwpid
, SIGSTOP
);
769 /* Finally, resume the stopped process. This will deliver the
770 SIGSTOP (or a higher priority signal, just like normal
771 PTRACE_ATTACH), which we'll catch later on. */
772 ptrace (PTRACE_CONT
, lwpid
, 0, 0);
775 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
778 There are several cases to consider here:
780 1) gdbserver has already attached to the process and is being notified
781 of a new thread that is being created.
782 In this case we should ignore that SIGSTOP and resume the
783 process. This is handled below by setting stop_expected = 1,
784 and the fact that add_thread sets last_resume_kind ==
787 2) This is the first thread (the process thread), and we're attaching
788 to it via attach_inferior.
789 In this case we want the process thread to stop.
790 This is handled by having linux_attach set last_resume_kind ==
791 resume_stop after we return.
793 If the pid we are attaching to is also the tgid, we attach to and
794 stop all the existing threads. Otherwise, we attach to pid and
795 ignore any other threads in the same group as this pid.
797 3) GDB is connecting to gdbserver and is requesting an enumeration of all
799 In this case we want the thread to stop.
800 FIXME: This case is currently not properly handled.
801 We should wait for the SIGSTOP but don't. Things work apparently
802 because enough time passes between when we ptrace (ATTACH) and when
803 gdb makes the next ptrace call on the thread.
805 On the other hand, if we are currently trying to stop all threads, we
806 should treat the new thread as if we had sent it a SIGSTOP. This works
807 because we are guaranteed that the add_lwp call above added us to the
808 end of the list, and so the new thread has not yet reached
809 wait_for_sigstop (but will). */
810 new_lwp
->stop_expected
= 1;
814 linux_attach_lwp (unsigned long lwpid
)
816 linux_attach_lwp_1 (lwpid
, 0);
819 /* Attach to PID. If PID is the tgid, attach to it and all
823 linux_attach (unsigned long pid
)
825 /* Attach to PID. We will check for other threads
827 linux_attach_lwp_1 (pid
, 1);
828 linux_add_process (pid
, 1);
832 struct thread_info
*thread
;
834 /* Don't ignore the initial SIGSTOP if we just attached to this
835 process. It will be collected by wait shortly. */
836 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
837 thread
->last_resume_kind
= resume_stop
;
840 if (linux_proc_get_tgid (pid
) == pid
)
845 sprintf (pathname
, "/proc/%ld/task", pid
);
847 dir
= opendir (pathname
);
851 fprintf (stderr
, "Could not open /proc/%ld/task.\n", pid
);
856 /* At this point we attached to the tgid. Scan the task for
859 int new_threads_found
;
863 while (iterations
< 2)
865 new_threads_found
= 0;
866 /* Add all the other threads. While we go through the
867 threads, new threads may be spawned. Cycle through
868 the list of threads until we have done two iterations without
869 finding new threads. */
870 while ((dp
= readdir (dir
)) != NULL
)
873 lwp
= strtoul (dp
->d_name
, NULL
, 10);
875 /* Is this a new thread? */
877 && find_thread_ptid (ptid_build (pid
, lwp
, 0)) == NULL
)
879 linux_attach_lwp_1 (lwp
, 0);
884 Found and attached to new lwp %ld\n", lwp
);
888 if (!new_threads_found
)
909 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
911 struct counter
*counter
= args
;
913 if (ptid_get_pid (entry
->id
) == counter
->pid
)
915 if (++counter
->count
> 1)
923 last_thread_of_process_p (struct thread_info
*thread
)
925 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
926 int pid
= ptid_get_pid (ptid
);
927 struct counter counter
= { pid
, 0 };
929 return (find_inferior (&all_threads
,
930 second_thread_of_pid_p
, &counter
) == NULL
);
936 linux_kill_one_lwp (struct lwp_info
*lwp
)
938 int pid
= lwpid_of (lwp
);
940 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
941 there is no signal context, and ptrace(PTRACE_KILL) (or
942 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
943 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
944 alternative is to kill with SIGKILL. We only need one SIGKILL
945 per process, not one for each thread. But since we still support
946 linuxthreads, and we also support debugging programs using raw
947 clone without CLONE_THREAD, we send one for each thread. For
948 years, we used PTRACE_KILL only, so we're being a bit paranoid
949 about some old kernels where PTRACE_KILL might work better
950 (dubious if there are any such, but that's why it's paranoia), so
951 we try SIGKILL first, PTRACE_KILL second, and so we're fine
958 "LKL: kill (SIGKILL) %s, 0, 0 (%s)\n",
959 target_pid_to_str (ptid_of (lwp
)),
960 errno
? strerror (errno
) : "OK");
963 ptrace (PTRACE_KILL
, pid
, 0, 0);
966 "LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
967 target_pid_to_str (ptid_of (lwp
)),
968 errno
? strerror (errno
) : "OK");
971 /* Callback for `find_inferior'. Kills an lwp of a given process,
972 except the leader. */
975 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
977 struct thread_info
*thread
= (struct thread_info
*) entry
;
978 struct lwp_info
*lwp
= get_thread_lwp (thread
);
980 int pid
= * (int *) args
;
982 if (ptid_get_pid (entry
->id
) != pid
)
985 /* We avoid killing the first thread here, because of a Linux kernel (at
986 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
987 the children get a chance to be reaped, it will remain a zombie
990 if (lwpid_of (lwp
) == pid
)
993 fprintf (stderr
, "lkop: is last of process %s\n",
994 target_pid_to_str (entry
->id
));
1000 linux_kill_one_lwp (lwp
);
1002 /* Make sure it died. The loop is most likely unnecessary. */
1003 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
1004 } while (pid
> 0 && WIFSTOPPED (wstat
));
1010 linux_kill (int pid
)
1012 struct process_info
*process
;
1013 struct lwp_info
*lwp
;
1017 process
= find_process_pid (pid
);
1018 if (process
== NULL
)
1021 /* If we're killing a running inferior, make sure it is stopped
1022 first, as PTRACE_KILL will not work otherwise. */
1023 stop_all_lwps (0, NULL
);
1025 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1027 /* See the comment in linux_kill_one_lwp. We did not kill the first
1028 thread in the list, so do so now. */
1029 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1034 fprintf (stderr
, "lk_1: cannot find lwp %ld, for pid: %d\n",
1035 lwpid_of (lwp
), pid
);
1040 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
1041 lwpid_of (lwp
), pid
);
1045 linux_kill_one_lwp (lwp
);
1047 /* Make sure it died. The loop is most likely unnecessary. */
1048 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
1049 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
1052 the_target
->mourn (process
);
1054 /* Since we presently can only stop all lwps of all processes, we
1055 need to unstop lwps of other processes. */
1056 unstop_all_lwps (0, NULL
);
1060 /* Get pending signal of THREAD, for detaching purposes. This is the
1061 signal the thread last stopped for, which we need to deliver to the
1062 thread when detaching, otherwise, it'd be suppressed/lost. */
1065 get_detach_signal (struct thread_info
*thread
)
1067 enum gdb_signal signo
= GDB_SIGNAL_0
;
1069 struct lwp_info
*lp
= get_thread_lwp (thread
);
1071 if (lp
->status_pending_p
)
1072 status
= lp
->status_pending
;
1075 /* If the thread had been suspended by gdbserver, and it stopped
1076 cleanly, then it'll have stopped with SIGSTOP. But we don't
1077 want to deliver that SIGSTOP. */
1078 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1079 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1082 /* Otherwise, we may need to deliver the signal we
1084 status
= lp
->last_status
;
1087 if (!WIFSTOPPED (status
))
1091 "GPS: lwp %s hasn't stopped: no pending signal\n",
1092 target_pid_to_str (ptid_of (lp
)));
1096 /* Extended wait statuses aren't real SIGTRAPs. */
1097 if (WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
1101 "GPS: lwp %s had stopped with extended "
1102 "status: no pending signal\n",
1103 target_pid_to_str (ptid_of (lp
)));
1107 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1109 if (program_signals_p
&& !program_signals
[signo
])
1113 "GPS: lwp %s had signal %s, but it is in nopass state\n",
1114 target_pid_to_str (ptid_of (lp
)),
1115 gdb_signal_to_string (signo
));
1118 else if (!program_signals_p
1119 /* If we have no way to know which signals GDB does not
1120 want to have passed to the program, assume
1121 SIGTRAP/SIGINT, which is GDB's default. */
1122 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1126 "GPS: lwp %s had signal %s, "
1127 "but we don't know if we should pass it. Default to not.\n",
1128 target_pid_to_str (ptid_of (lp
)),
1129 gdb_signal_to_string (signo
));
1136 "GPS: lwp %s has pending signal %s: delivering it.\n",
1137 target_pid_to_str (ptid_of (lp
)),
1138 gdb_signal_to_string (signo
));
1140 return WSTOPSIG (status
);
1145 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1147 struct thread_info
*thread
= (struct thread_info
*) entry
;
1148 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1149 int pid
= * (int *) args
;
1152 if (ptid_get_pid (entry
->id
) != pid
)
1155 /* If there is a pending SIGSTOP, get rid of it. */
1156 if (lwp
->stop_expected
)
1160 "Sending SIGCONT to %s\n",
1161 target_pid_to_str (ptid_of (lwp
)));
1163 kill_lwp (lwpid_of (lwp
), SIGCONT
);
1164 lwp
->stop_expected
= 0;
1167 /* Flush any pending changes to the process's registers. */
1168 regcache_invalidate_one ((struct inferior_list_entry
*)
1169 get_lwp_thread (lwp
));
1171 /* Pass on any pending signal for this thread. */
1172 sig
= get_detach_signal (thread
);
1174 /* Finally, let it resume. */
1175 if (the_low_target
.prepare_to_resume
!= NULL
)
1176 the_low_target
.prepare_to_resume (lwp
);
1177 if (ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0,
1178 (PTRACE_ARG4_TYPE
) (long) sig
) < 0)
1179 error (_("Can't detach %s: %s"),
1180 target_pid_to_str (ptid_of (lwp
)),
1188 linux_detach (int pid
)
1190 struct process_info
*process
;
1192 process
= find_process_pid (pid
);
1193 if (process
== NULL
)
1196 /* Stop all threads before detaching. First, ptrace requires that
1197 the thread is stopped to sucessfully detach. Second, thread_db
1198 may need to uninstall thread event breakpoints from memory, which
1199 only works with a stopped process anyway. */
1200 stop_all_lwps (0, NULL
);
1202 #ifdef USE_THREAD_DB
1203 thread_db_detach (process
);
1206 /* Stabilize threads (move out of jump pads). */
1207 stabilize_threads ();
1209 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1211 the_target
->mourn (process
);
1213 /* Since we presently can only stop all lwps of all processes, we
1214 need to unstop lwps of other processes. */
1215 unstop_all_lwps (0, NULL
);
1219 /* Remove all LWPs that belong to process PROC from the lwp list. */
1222 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1224 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1225 struct process_info
*process
= proc
;
1227 if (pid_of (lwp
) == pid_of (process
))
1234 linux_mourn (struct process_info
*process
)
1236 struct process_info_private
*priv
;
1238 #ifdef USE_THREAD_DB
1239 thread_db_mourn (process
);
1242 find_inferior (&all_lwps
, delete_lwp_callback
, process
);
1244 /* Freeing all private data. */
1245 priv
= process
->private;
1246 free (priv
->arch_private
);
1248 process
->private = NULL
;
1250 remove_process (process
);
1254 linux_join (int pid
)
1259 ret
= my_waitpid (pid
, &status
, 0);
1260 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1262 } while (ret
!= -1 || errno
!= ECHILD
);
1265 /* Return nonzero if the given thread is still alive. */
1267 linux_thread_alive (ptid_t ptid
)
1269 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1271 /* We assume we always know if a thread exits. If a whole process
1272 exited but we still haven't been able to report it to GDB, we'll
1273 hold on to the last lwp of the dead process. */
1280 /* Return 1 if this lwp has an interesting status pending. */
1282 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1284 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1285 ptid_t ptid
= * (ptid_t
*) arg
;
1286 struct thread_info
*thread
;
1288 /* Check if we're only interested in events from a specific process
1290 if (!ptid_equal (minus_one_ptid
, ptid
)
1291 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
1294 thread
= get_lwp_thread (lwp
);
1296 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1297 report any status pending the LWP may have. */
1298 if (thread
->last_resume_kind
== resume_stop
1299 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1302 return lwp
->status_pending_p
;
1306 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1308 ptid_t ptid
= *(ptid_t
*) data
;
1311 if (ptid_get_lwp (ptid
) != 0)
1312 lwp
= ptid_get_lwp (ptid
);
1314 lwp
= ptid_get_pid (ptid
);
1316 if (ptid_get_lwp (entry
->id
) == lwp
)
1323 find_lwp_pid (ptid_t ptid
)
1325 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
1328 static struct lwp_info
*
1329 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
1332 int to_wait_for
= -1;
1333 struct lwp_info
*child
= NULL
;
1336 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1338 if (ptid_equal (ptid
, minus_one_ptid
))
1339 to_wait_for
= -1; /* any child */
1341 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1347 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1348 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1351 perror_with_name ("waitpid");
1354 && (!WIFSTOPPED (*wstatp
)
1355 || (WSTOPSIG (*wstatp
) != 32
1356 && WSTOPSIG (*wstatp
) != 33)))
1357 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1359 child
= find_lwp_pid (pid_to_ptid (ret
));
1361 /* If we didn't find a process, one of two things presumably happened:
1362 - A process we started and then detached from has exited. Ignore it.
1363 - A process we are controlling has forked and the new child's stop
1364 was reported to us by the kernel. Save its PID. */
1365 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1367 add_to_pid_list (&stopped_pids
, ret
, *wstatp
);
1370 else if (child
== NULL
)
1375 child
->last_status
= *wstatp
;
1377 /* Architecture-specific setup after inferior is running.
1378 This needs to happen after we have attached to the inferior
1379 and it is stopped for the first time, but before we access
1380 any inferior registers. */
1383 the_low_target
.arch_setup ();
1384 #ifdef HAVE_LINUX_REGSETS
1385 memset (disabled_regsets
, 0, num_regsets
);
1390 /* Fetch the possibly triggered data watchpoint info and store it in
1393 On some archs, like x86, that use debug registers to set
1394 watchpoints, it's possible that the way to know which watched
1395 address trapped, is to check the register that is used to select
1396 which address to watch. Problem is, between setting the
1397 watchpoint and reading back which data address trapped, the user
1398 may change the set of watchpoints, and, as a consequence, GDB
1399 changes the debug registers in the inferior. To avoid reading
1400 back a stale stopped-data-address when that happens, we cache in
1401 LP the fact that a watchpoint trapped, and the corresponding data
1402 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1403 changes the debug registers meanwhile, we have the cached data we
1406 if (WIFSTOPPED (*wstatp
) && WSTOPSIG (*wstatp
) == SIGTRAP
)
1408 if (the_low_target
.stopped_by_watchpoint
== NULL
)
1410 child
->stopped_by_watchpoint
= 0;
1414 struct thread_info
*saved_inferior
;
1416 saved_inferior
= current_inferior
;
1417 current_inferior
= get_lwp_thread (child
);
1419 child
->stopped_by_watchpoint
1420 = the_low_target
.stopped_by_watchpoint ();
1422 if (child
->stopped_by_watchpoint
)
1424 if (the_low_target
.stopped_data_address
!= NULL
)
1425 child
->stopped_data_address
1426 = the_low_target
.stopped_data_address ();
1428 child
->stopped_data_address
= 0;
1431 current_inferior
= saved_inferior
;
1435 /* Store the STOP_PC, with adjustment applied. This depends on the
1436 architecture being defined already (so that CHILD has a valid
1437 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1439 if (WIFSTOPPED (*wstatp
))
1440 child
->stop_pc
= get_stop_pc (child
);
1443 && WIFSTOPPED (*wstatp
)
1444 && the_low_target
.get_pc
!= NULL
)
1446 struct thread_info
*saved_inferior
= current_inferior
;
1447 struct regcache
*regcache
;
1450 current_inferior
= get_lwp_thread (child
);
1451 regcache
= get_thread_regcache (current_inferior
, 1);
1452 pc
= (*the_low_target
.get_pc
) (regcache
);
1453 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1454 current_inferior
= saved_inferior
;
1460 /* This function should only be called if the LWP got a SIGTRAP.
1462 Handle any tracepoint steps or hits. Return true if a tracepoint
1463 event was handled, 0 otherwise. */
1466 handle_tracepoints (struct lwp_info
*lwp
)
1468 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1469 int tpoint_related_event
= 0;
1471 /* If this tracepoint hit causes a tracing stop, we'll immediately
1472 uninsert tracepoints. To do this, we temporarily pause all
1473 threads, unpatch away, and then unpause threads. We need to make
1474 sure the unpausing doesn't resume LWP too. */
1477 /* And we need to be sure that any all-threads-stopping doesn't try
1478 to move threads out of the jump pads, as it could deadlock the
1479 inferior (LWP could be in the jump pad, maybe even holding the
1482 /* Do any necessary step collect actions. */
1483 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1485 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1487 /* See if we just hit a tracepoint and do its main collect
1489 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1493 gdb_assert (lwp
->suspended
== 0);
1494 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1496 if (tpoint_related_event
)
1499 fprintf (stderr
, "got a tracepoint event\n");
1506 /* Convenience wrapper. Returns true if LWP is presently collecting a
1510 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1511 struct fast_tpoint_collect_status
*status
)
1513 CORE_ADDR thread_area
;
1515 if (the_low_target
.get_thread_area
== NULL
)
1518 /* Get the thread area address. This is used to recognize which
1519 thread is which when tracing with the in-process agent library.
1520 We don't read anything from the address, and treat it as opaque;
1521 it's the address itself that we assume is unique per-thread. */
1522 if ((*the_low_target
.get_thread_area
) (lwpid_of (lwp
), &thread_area
) == -1)
1525 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1528 /* The reason we resume in the caller, is because we want to be able
1529 to pass lwp->status_pending as WSTAT, and we need to clear
1530 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1531 refuses to resume. */
1534 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1536 struct thread_info
*saved_inferior
;
1538 saved_inferior
= current_inferior
;
1539 current_inferior
= get_lwp_thread (lwp
);
1542 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1543 && supports_fast_tracepoints ()
1544 && agent_loaded_p ())
1546 struct fast_tpoint_collect_status status
;
1551 Checking whether LWP %ld needs to move out of the jump pad.\n",
1554 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1557 || (WSTOPSIG (*wstat
) != SIGILL
1558 && WSTOPSIG (*wstat
) != SIGFPE
1559 && WSTOPSIG (*wstat
) != SIGSEGV
1560 && WSTOPSIG (*wstat
) != SIGBUS
))
1562 lwp
->collecting_fast_tracepoint
= r
;
1566 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1568 /* Haven't executed the original instruction yet.
1569 Set breakpoint there, and wait till it's hit,
1570 then single-step until exiting the jump pad. */
1571 lwp
->exit_jump_pad_bkpt
1572 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1577 Checking whether LWP %ld needs to move out of the jump pad...it does\n",
1579 current_inferior
= saved_inferior
;
1586 /* If we get a synchronous signal while collecting, *and*
1587 while executing the (relocated) original instruction,
1588 reset the PC to point at the tpoint address, before
1589 reporting to GDB. Otherwise, it's an IPA lib bug: just
1590 report the signal to GDB, and pray for the best. */
1592 lwp
->collecting_fast_tracepoint
= 0;
1595 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1596 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1599 struct regcache
*regcache
;
1601 /* The si_addr on a few signals references the address
1602 of the faulting instruction. Adjust that as
1604 if ((WSTOPSIG (*wstat
) == SIGILL
1605 || WSTOPSIG (*wstat
) == SIGFPE
1606 || WSTOPSIG (*wstat
) == SIGBUS
1607 || WSTOPSIG (*wstat
) == SIGSEGV
)
1608 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &info
) == 0
1609 /* Final check just to make sure we don't clobber
1610 the siginfo of non-kernel-sent signals. */
1611 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1613 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1614 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &info
);
1617 regcache
= get_thread_regcache (get_lwp_thread (lwp
), 1);
1618 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1619 lwp
->stop_pc
= status
.tpoint_addr
;
1621 /* Cancel any fast tracepoint lock this thread was
1623 force_unlock_trace_buffer ();
1626 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1630 "Cancelling fast exit-jump-pad: removing bkpt. "
1631 "stopping all threads momentarily.\n");
1633 stop_all_lwps (1, lwp
);
1634 cancel_breakpoints ();
1636 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1637 lwp
->exit_jump_pad_bkpt
= NULL
;
1639 unstop_all_lwps (1, lwp
);
1641 gdb_assert (lwp
->suspended
>= 0);
1648 Checking whether LWP %ld needs to move out of the jump pad...no\n",
1651 current_inferior
= saved_inferior
;
1655 /* Enqueue one signal in the "signals to report later when out of the
1659 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1661 struct pending_signals
*p_sig
;
1665 Deferring signal %d for LWP %ld.\n", WSTOPSIG (*wstat
), lwpid_of (lwp
));
1669 struct pending_signals
*sig
;
1671 for (sig
= lwp
->pending_signals_to_report
;
1675 " Already queued %d\n",
1678 fprintf (stderr
, " (no more currently queued signals)\n");
1681 /* Don't enqueue non-RT signals if they are already in the deferred
1682 queue. (SIGSTOP being the easiest signal to see ending up here
1684 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1686 struct pending_signals
*sig
;
1688 for (sig
= lwp
->pending_signals_to_report
;
1692 if (sig
->signal
== WSTOPSIG (*wstat
))
1696 "Not requeuing already queued non-RT signal %d"
1705 p_sig
= xmalloc (sizeof (*p_sig
));
1706 p_sig
->prev
= lwp
->pending_signals_to_report
;
1707 p_sig
->signal
= WSTOPSIG (*wstat
);
1708 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1709 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
1711 lwp
->pending_signals_to_report
= p_sig
;
1714 /* Dequeue one signal from the "signals to report later when out of
1715 the jump pad" list. */
1718 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1720 if (lwp
->pending_signals_to_report
!= NULL
)
1722 struct pending_signals
**p_sig
;
1724 p_sig
= &lwp
->pending_signals_to_report
;
1725 while ((*p_sig
)->prev
!= NULL
)
1726 p_sig
= &(*p_sig
)->prev
;
1728 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1729 if ((*p_sig
)->info
.si_signo
!= 0)
1730 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
1735 fprintf (stderr
, "Reporting deferred signal %d for LWP %ld.\n",
1736 WSTOPSIG (*wstat
), lwpid_of (lwp
));
1740 struct pending_signals
*sig
;
1742 for (sig
= lwp
->pending_signals_to_report
;
1746 " Still queued %d\n",
1749 fprintf (stderr
, " (no more queued signals)\n");
1758 /* Arrange for a breakpoint to be hit again later. We don't keep the
1759 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1760 will handle the current event, eventually we will resume this LWP,
1761 and this breakpoint will trap again. */
1764 cancel_breakpoint (struct lwp_info
*lwp
)
1766 struct thread_info
*saved_inferior
;
1768 /* There's nothing to do if we don't support breakpoints. */
1769 if (!supports_breakpoints ())
1772 /* breakpoint_at reads from current inferior. */
1773 saved_inferior
= current_inferior
;
1774 current_inferior
= get_lwp_thread (lwp
);
1776 if ((*the_low_target
.breakpoint_at
) (lwp
->stop_pc
))
1780 "CB: Push back breakpoint for %s\n",
1781 target_pid_to_str (ptid_of (lwp
)));
1783 /* Back up the PC if necessary. */
1784 if (the_low_target
.decr_pc_after_break
)
1786 struct regcache
*regcache
1787 = get_thread_regcache (current_inferior
, 1);
1788 (*the_low_target
.set_pc
) (regcache
, lwp
->stop_pc
);
1791 current_inferior
= saved_inferior
;
1798 "CB: No breakpoint found at %s for [%s]\n",
1799 paddress (lwp
->stop_pc
),
1800 target_pid_to_str (ptid_of (lwp
)));
1803 current_inferior
= saved_inferior
;
1807 /* When the event-loop is doing a step-over, this points at the thread
1809 ptid_t step_over_bkpt
;
1811 /* Wait for an event from child PID. If PID is -1, wait for any
1812 child. Store the stop status through the status pointer WSTAT.
1813 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1814 event was found and OPTIONS contains WNOHANG. Return the PID of
1815 the stopped child otherwise. */
1818 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1820 struct lwp_info
*event_child
, *requested_child
;
1824 requested_child
= NULL
;
1826 /* Check for a lwp with a pending status. */
1828 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
1830 event_child
= (struct lwp_info
*)
1831 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1832 if (debug_threads
&& event_child
)
1833 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1837 requested_child
= find_lwp_pid (ptid
);
1839 if (stopping_threads
== NOT_STOPPING_THREADS
1840 && requested_child
->status_pending_p
1841 && requested_child
->collecting_fast_tracepoint
)
1843 enqueue_one_deferred_signal (requested_child
,
1844 &requested_child
->status_pending
);
1845 requested_child
->status_pending_p
= 0;
1846 requested_child
->status_pending
= 0;
1847 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
1850 if (requested_child
->suspended
1851 && requested_child
->status_pending_p
)
1852 fatal ("requesting an event out of a suspended child?");
1854 if (requested_child
->status_pending_p
)
1855 event_child
= requested_child
;
1858 if (event_child
!= NULL
)
1861 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1862 lwpid_of (event_child
), event_child
->status_pending
);
1863 *wstat
= event_child
->status_pending
;
1864 event_child
->status_pending_p
= 0;
1865 event_child
->status_pending
= 0;
1866 current_inferior
= get_lwp_thread (event_child
);
1867 return lwpid_of (event_child
);
1870 if (ptid_is_pid (ptid
))
1872 /* A request to wait for a specific tgid. This is not possible
1873 with waitpid, so instead, we wait for any child, and leave
1874 children we're not interested in right now with a pending
1875 status to report later. */
1876 wait_ptid
= minus_one_ptid
;
1881 /* We only enter this loop if no process has a pending wait status. Thus
1882 any action taken in response to a wait status inside this loop is
1883 responding as soon as we detect the status, not after any pending
1887 event_child
= linux_wait_for_lwp (wait_ptid
, wstat
, options
);
1889 if ((options
& WNOHANG
) && event_child
== NULL
)
1892 fprintf (stderr
, "WNOHANG set, no event found\n");
1896 if (event_child
== NULL
)
1897 error ("event from unknown child");
1899 if (ptid_is_pid (ptid
)
1900 && ptid_get_pid (ptid
) != ptid_get_pid (ptid_of (event_child
)))
1902 if (! WIFSTOPPED (*wstat
))
1903 mark_lwp_dead (event_child
, *wstat
);
1906 event_child
->status_pending_p
= 1;
1907 event_child
->status_pending
= *wstat
;
1912 current_inferior
= get_lwp_thread (event_child
);
1914 /* Check for thread exit. */
1915 if (! WIFSTOPPED (*wstat
))
1918 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1920 /* If the last thread is exiting, just return. */
1921 if (last_thread_of_process_p (current_inferior
))
1924 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1925 lwpid_of (event_child
));
1926 return lwpid_of (event_child
);
1931 current_inferior
= (struct thread_info
*) all_threads
.head
;
1933 fprintf (stderr
, "Current inferior is now %ld\n",
1934 lwpid_of (get_thread_lwp (current_inferior
)));
1938 current_inferior
= NULL
;
1940 fprintf (stderr
, "Current inferior is now <NULL>\n");
1943 /* If we were waiting for this particular child to do something...
1944 well, it did something. */
1945 if (requested_child
!= NULL
)
1947 int lwpid
= lwpid_of (event_child
);
1949 /* Cancel the step-over operation --- the thread that
1950 started it is gone. */
1951 if (finish_step_over (event_child
))
1952 unstop_all_lwps (1, event_child
);
1953 delete_lwp (event_child
);
1957 delete_lwp (event_child
);
1959 /* Wait for a more interesting event. */
1963 if (event_child
->must_set_ptrace_flags
)
1965 linux_enable_event_reporting (lwpid_of (event_child
));
1966 event_child
->must_set_ptrace_flags
= 0;
1969 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1970 && *wstat
>> 16 != 0)
1972 handle_extended_wait (event_child
, *wstat
);
1976 if (WIFSTOPPED (*wstat
)
1977 && WSTOPSIG (*wstat
) == SIGSTOP
1978 && event_child
->stop_expected
)
1983 fprintf (stderr
, "Expected stop.\n");
1984 event_child
->stop_expected
= 0;
1986 should_stop
= (current_inferior
->last_resume_kind
== resume_stop
1987 || stopping_threads
!= NOT_STOPPING_THREADS
);
1991 linux_resume_one_lwp (event_child
,
1992 event_child
->stepping
, 0, NULL
);
1997 return lwpid_of (event_child
);
2004 /* Count the LWP's that have had events. */
2007 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2009 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2010 struct thread_info
*thread
= get_lwp_thread (lp
);
2013 gdb_assert (count
!= NULL
);
2015 /* Count only resumed LWPs that have a SIGTRAP event pending that
2016 should be reported to GDB. */
2017 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2018 && thread
->last_resume_kind
!= resume_stop
2019 && lp
->status_pending_p
2020 && WIFSTOPPED (lp
->status_pending
)
2021 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2022 && !breakpoint_inserted_here (lp
->stop_pc
))
2028 /* Select the LWP (if any) that is currently being single-stepped. */
2031 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2033 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2034 struct thread_info
*thread
= get_lwp_thread (lp
);
2036 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2037 && thread
->last_resume_kind
== resume_step
2038 && lp
->status_pending_p
)
2044 /* Select the Nth LWP that has had a SIGTRAP event that should be
2048 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2050 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2051 struct thread_info
*thread
= get_lwp_thread (lp
);
2052 int *selector
= data
;
2054 gdb_assert (selector
!= NULL
);
2056 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2057 if (thread
->last_resume_kind
!= resume_stop
2058 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2059 && lp
->status_pending_p
2060 && WIFSTOPPED (lp
->status_pending
)
2061 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2062 && !breakpoint_inserted_here (lp
->stop_pc
))
2063 if ((*selector
)-- == 0)
2070 cancel_breakpoints_callback (struct inferior_list_entry
*entry
, void *data
)
2072 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2073 struct thread_info
*thread
= get_lwp_thread (lp
);
2074 struct lwp_info
*event_lp
= data
;
2076 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
2080 /* If a LWP other than the LWP that we're reporting an event for has
2081 hit a GDB breakpoint (as opposed to some random trap signal),
2082 then just arrange for it to hit it again later. We don't keep
2083 the SIGTRAP status and don't forward the SIGTRAP signal to the
2084 LWP. We will handle the current event, eventually we will resume
2085 all LWPs, and this one will get its breakpoint trap again.
2087 If we do not do this, then we run the risk that the user will
2088 delete or disable the breakpoint, but the LWP will have already
2091 if (thread
->last_resume_kind
!= resume_stop
2092 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2093 && lp
->status_pending_p
2094 && WIFSTOPPED (lp
->status_pending
)
2095 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2097 && !lp
->stopped_by_watchpoint
2098 && cancel_breakpoint (lp
))
2099 /* Throw away the SIGTRAP. */
2100 lp
->status_pending_p
= 0;
2106 linux_cancel_breakpoints (void)
2108 find_inferior (&all_lwps
, cancel_breakpoints_callback
, NULL
);
2111 /* Select one LWP out of those that have events pending. */
2114 select_event_lwp (struct lwp_info
**orig_lp
)
2117 int random_selector
;
2118 struct lwp_info
*event_lp
;
2120 /* Give preference to any LWP that is being single-stepped. */
2122 = (struct lwp_info
*) find_inferior (&all_lwps
,
2123 select_singlestep_lwp_callback
, NULL
);
2124 if (event_lp
!= NULL
)
2128 "SEL: Select single-step %s\n",
2129 target_pid_to_str (ptid_of (event_lp
)));
2133 /* No single-stepping LWP. Select one at random, out of those
2134 which have had SIGTRAP events. */
2136 /* First see how many SIGTRAP events we have. */
2137 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
2139 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
2140 random_selector
= (int)
2141 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2143 if (debug_threads
&& num_events
> 1)
2145 "SEL: Found %d SIGTRAP events, selecting #%d\n",
2146 num_events
, random_selector
);
2148 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
2149 select_event_lwp_callback
,
2153 if (event_lp
!= NULL
)
2155 /* Switch the event LWP. */
2156 *orig_lp
= event_lp
;
2160 /* Decrement the suspend count of an LWP. */
2163 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2165 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2167 /* Ignore EXCEPT. */
2173 gdb_assert (lwp
->suspended
>= 0);
2177 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2181 unsuspend_all_lwps (struct lwp_info
*except
)
2183 find_inferior (&all_lwps
, unsuspend_one_lwp
, except
);
2186 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2187 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2189 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2190 static ptid_t
linux_wait_1 (ptid_t ptid
,
2191 struct target_waitstatus
*ourstatus
,
2192 int target_options
);
2194 /* Stabilize threads (move out of jump pads).
2196 If a thread is midway collecting a fast tracepoint, we need to
2197 finish the collection and move it out of the jump pad before
2198 reporting the signal.
2200 This avoids recursion while collecting (when a signal arrives
2201 midway, and the signal handler itself collects), which would trash
2202 the trace buffer. In case the user set a breakpoint in a signal
2203 handler, this avoids the backtrace showing the jump pad, etc..
2204 Most importantly, there are certain things we can't do safely if
2205 threads are stopped in a jump pad (or in its callee's). For
2208 - starting a new trace run. A thread still collecting the
2209 previous run, could trash the trace buffer when resumed. The trace
2210 buffer control structures would have been reset but the thread had
2211 no way to tell. The thread could even midway memcpy'ing to the
2212 buffer, which would mean that when resumed, it would clobber the
2213 trace buffer that had been set for a new run.
2215 - we can't rewrite/reuse the jump pads for new tracepoints
2216 safely. Say you do tstart while a thread is stopped midway while
2217 collecting. When the thread is later resumed, it finishes the
2218 collection, and returns to the jump pad, to execute the original
2219 instruction that was under the tracepoint jump at the time the
2220 older run had been started. If the jump pad had been rewritten
2221 since for something else in the new run, the thread would now
2222 execute the wrong / random instructions. */
2225 linux_stabilize_threads (void)
2227 struct thread_info
*save_inferior
;
2228 struct lwp_info
*lwp_stuck
;
2231 = (struct lwp_info
*) find_inferior (&all_lwps
,
2232 stuck_in_jump_pad_callback
, NULL
);
2233 if (lwp_stuck
!= NULL
)
2236 fprintf (stderr
, "can't stabilize, LWP %ld is stuck in jump pad\n",
2237 lwpid_of (lwp_stuck
));
2241 save_inferior
= current_inferior
;
2243 stabilizing_threads
= 1;
2246 for_each_inferior (&all_lwps
, move_out_of_jump_pad_callback
);
2248 /* Loop until all are stopped out of the jump pads. */
2249 while (find_inferior (&all_lwps
, lwp_running
, NULL
) != NULL
)
2251 struct target_waitstatus ourstatus
;
2252 struct lwp_info
*lwp
;
2255 /* Note that we go through the full wait even loop. While
2256 moving threads out of jump pad, we need to be able to step
2257 over internal breakpoints and such. */
2258 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2260 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2262 lwp
= get_thread_lwp (current_inferior
);
2267 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2268 || current_inferior
->last_resume_kind
== resume_stop
)
2270 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2271 enqueue_one_deferred_signal (lwp
, &wstat
);
2276 find_inferior (&all_lwps
, unsuspend_one_lwp
, NULL
);
2278 stabilizing_threads
= 0;
2280 current_inferior
= save_inferior
;
2285 = (struct lwp_info
*) find_inferior (&all_lwps
,
2286 stuck_in_jump_pad_callback
, NULL
);
2287 if (lwp_stuck
!= NULL
)
2288 fprintf (stderr
, "couldn't stabilize, LWP %ld got stuck in jump pad\n",
2289 lwpid_of (lwp_stuck
));
2293 /* Wait for process, returns status. */
2296 linux_wait_1 (ptid_t ptid
,
2297 struct target_waitstatus
*ourstatus
, int target_options
)
2300 struct lwp_info
*event_child
;
2303 int step_over_finished
;
2304 int bp_explains_trap
;
2305 int maybe_internal_trap
;
2309 /* Translate generic target options into linux options. */
2311 if (target_options
& TARGET_WNOHANG
)
2315 bp_explains_trap
= 0;
2317 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2319 /* If we were only supposed to resume one thread, only wait for
2320 that thread - if it's still alive. If it died, however - which
2321 can happen if we're coming from the thread death case below -
2322 then we need to make sure we restart the other threads. We could
2323 pick a thread at random or restart all; restarting all is less
2326 && !ptid_equal (cont_thread
, null_ptid
)
2327 && !ptid_equal (cont_thread
, minus_one_ptid
))
2329 struct thread_info
*thread
;
2331 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
2334 /* No stepping, no signal - unless one is pending already, of course. */
2337 struct thread_resume resume_info
;
2338 resume_info
.thread
= minus_one_ptid
;
2339 resume_info
.kind
= resume_continue
;
2340 resume_info
.sig
= 0;
2341 linux_resume (&resume_info
, 1);
2347 if (ptid_equal (step_over_bkpt
, null_ptid
))
2348 pid
= linux_wait_for_event (ptid
, &w
, options
);
2352 fprintf (stderr
, "step_over_bkpt set [%s], doing a blocking wait\n",
2353 target_pid_to_str (step_over_bkpt
));
2354 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2357 if (pid
== 0) /* only if TARGET_WNOHANG */
2360 event_child
= get_thread_lwp (current_inferior
);
2362 /* If we are waiting for a particular child, and it exited,
2363 linux_wait_for_event will return its exit status. Similarly if
2364 the last child exited. If this is not the last child, however,
2365 do not report it as exited until there is a 'thread exited' response
2366 available in the remote protocol. Instead, just wait for another event.
2367 This should be safe, because if the thread crashed we will already
2368 have reported the termination signal to GDB; that should stop any
2369 in-progress stepping operations, etc.
2371 Report the exit status of the last thread to exit. This matches
2372 LinuxThreads' behavior. */
2374 if (last_thread_of_process_p (current_inferior
))
2376 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2380 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2381 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2385 "\nChild exited with retcode = %x \n",
2390 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2391 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
2395 "\nChild terminated with signal = %x \n",
2400 return ptid_of (event_child
);
2405 if (!WIFSTOPPED (w
))
2409 /* If this event was not handled before, and is not a SIGTRAP, we
2410 report it. SIGILL and SIGSEGV are also treated as traps in case
2411 a breakpoint is inserted at the current PC. If this target does
2412 not support internal breakpoints at all, we also report the
2413 SIGTRAP without further processing; it's of no concern to us. */
2415 = (supports_breakpoints ()
2416 && (WSTOPSIG (w
) == SIGTRAP
2417 || ((WSTOPSIG (w
) == SIGILL
2418 || WSTOPSIG (w
) == SIGSEGV
)
2419 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2421 if (maybe_internal_trap
)
2423 /* Handle anything that requires bookkeeping before deciding to
2424 report the event or continue waiting. */
2426 /* First check if we can explain the SIGTRAP with an internal
2427 breakpoint, or if we should possibly report the event to GDB.
2428 Do this before anything that may remove or insert a
2430 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2432 /* We have a SIGTRAP, possibly a step-over dance has just
2433 finished. If so, tweak the state machine accordingly,
2434 reinsert breakpoints and delete any reinsert (software
2435 single-step) breakpoints. */
2436 step_over_finished
= finish_step_over (event_child
);
2438 /* Now invoke the callbacks of any internal breakpoints there. */
2439 check_breakpoints (event_child
->stop_pc
);
2441 /* Handle tracepoint data collecting. This may overflow the
2442 trace buffer, and cause a tracing stop, removing
2444 trace_event
= handle_tracepoints (event_child
);
2446 if (bp_explains_trap
)
2448 /* If we stepped or ran into an internal breakpoint, we've
2449 already handled it. So next time we resume (from this
2450 PC), we should step over it. */
2452 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2454 if (breakpoint_here (event_child
->stop_pc
))
2455 event_child
->need_step_over
= 1;
2460 /* We have some other signal, possibly a step-over dance was in
2461 progress, and it should be cancelled too. */
2462 step_over_finished
= finish_step_over (event_child
);
2465 /* We have all the data we need. Either report the event to GDB, or
2466 resume threads and keep waiting for more. */
2468 /* If we're collecting a fast tracepoint, finish the collection and
2469 move out of the jump pad before delivering a signal. See
2470 linux_stabilize_threads. */
2473 && WSTOPSIG (w
) != SIGTRAP
2474 && supports_fast_tracepoints ()
2475 && agent_loaded_p ())
2479 "Got signal %d for LWP %ld. Check if we need "
2480 "to defer or adjust it.\n",
2481 WSTOPSIG (w
), lwpid_of (event_child
));
2483 /* Allow debugging the jump pad itself. */
2484 if (current_inferior
->last_resume_kind
!= resume_step
2485 && maybe_move_out_of_jump_pad (event_child
, &w
))
2487 enqueue_one_deferred_signal (event_child
, &w
);
2491 "Signal %d for LWP %ld deferred (in jump pad)\n",
2492 WSTOPSIG (w
), lwpid_of (event_child
));
2494 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2499 if (event_child
->collecting_fast_tracepoint
)
2503 LWP %ld was trying to move out of the jump pad (%d). \
2504 Check if we're already there.\n",
2505 lwpid_of (event_child
),
2506 event_child
->collecting_fast_tracepoint
);
2510 event_child
->collecting_fast_tracepoint
2511 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2513 if (event_child
->collecting_fast_tracepoint
!= 1)
2515 /* No longer need this breakpoint. */
2516 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2520 "No longer need exit-jump-pad bkpt; removing it."
2521 "stopping all threads momentarily.\n");
2523 /* Other running threads could hit this breakpoint.
2524 We don't handle moribund locations like GDB does,
2525 instead we always pause all threads when removing
2526 breakpoints, so that any step-over or
2527 decr_pc_after_break adjustment is always taken
2528 care of while the breakpoint is still
2530 stop_all_lwps (1, event_child
);
2531 cancel_breakpoints ();
2533 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2534 event_child
->exit_jump_pad_bkpt
= NULL
;
2536 unstop_all_lwps (1, event_child
);
2538 gdb_assert (event_child
->suspended
>= 0);
2542 if (event_child
->collecting_fast_tracepoint
== 0)
2546 "fast tracepoint finished "
2547 "collecting successfully.\n");
2549 /* We may have a deferred signal to report. */
2550 if (dequeue_one_deferred_signal (event_child
, &w
))
2553 fprintf (stderr
, "dequeued one signal.\n");
2558 fprintf (stderr
, "no deferred signals.\n");
2560 if (stabilizing_threads
)
2562 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2563 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
2564 return ptid_of (event_child
);
2570 /* Check whether GDB would be interested in this event. */
2572 /* If GDB is not interested in this signal, don't stop other
2573 threads, and don't report it to GDB. Just resume the inferior
2574 right away. We do this for threading-related signals as well as
2575 any that GDB specifically requested we ignore. But never ignore
2576 SIGSTOP if we sent it ourselves, and do not ignore signals when
2577 stepping - they may require special handling to skip the signal
2579 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2582 && current_inferior
->last_resume_kind
!= resume_step
2584 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2585 (current_process ()->private->thread_db
!= NULL
2586 && (WSTOPSIG (w
) == __SIGRTMIN
2587 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2590 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
2591 && !(WSTOPSIG (w
) == SIGSTOP
2592 && current_inferior
->last_resume_kind
== resume_stop
))))
2594 siginfo_t info
, *info_p
;
2597 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
2598 WSTOPSIG (w
), lwpid_of (event_child
));
2600 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
2604 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2605 WSTOPSIG (w
), info_p
);
2609 /* If GDB wanted this thread to single step, we always want to
2610 report the SIGTRAP, and let GDB handle it. Watchpoints should
2611 always be reported. So should signals we can't explain. A
2612 SIGTRAP we can't explain could be a GDB breakpoint --- we may or
2613 not support Z0 breakpoints. If we do, we're be able to handle
2614 GDB breakpoints on top of internal breakpoints, by handling the
2615 internal breakpoint and still reporting the event to GDB. If we
2616 don't, we're out of luck, GDB won't see the breakpoint hit. */
2617 report_to_gdb
= (!maybe_internal_trap
2618 || current_inferior
->last_resume_kind
== resume_step
2619 || event_child
->stopped_by_watchpoint
2620 || (!step_over_finished
2621 && !bp_explains_trap
&& !trace_event
)
2622 || (gdb_breakpoint_here (event_child
->stop_pc
)
2623 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
2624 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
)));
2626 run_breakpoint_commands (event_child
->stop_pc
);
2628 /* We found no reason GDB would want us to stop. We either hit one
2629 of our own breakpoints, or finished an internal step GDB
2630 shouldn't know about. */
2635 if (bp_explains_trap
)
2636 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2637 if (step_over_finished
)
2638 fprintf (stderr
, "Step-over finished.\n");
2640 fprintf (stderr
, "Tracepoint event.\n");
2643 /* We're not reporting this breakpoint to GDB, so apply the
2644 decr_pc_after_break adjustment to the inferior's regcache
2647 if (the_low_target
.set_pc
!= NULL
)
2649 struct regcache
*regcache
2650 = get_thread_regcache (get_lwp_thread (event_child
), 1);
2651 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2654 /* We may have finished stepping over a breakpoint. If so,
2655 we've stopped and suspended all LWPs momentarily except the
2656 stepping one. This is where we resume them all again. We're
2657 going to keep waiting, so use proceed, which handles stepping
2658 over the next breakpoint. */
2660 fprintf (stderr
, "proceeding all threads.\n");
2662 if (step_over_finished
)
2663 unsuspend_all_lwps (event_child
);
2665 proceed_all_lwps ();
2671 if (current_inferior
->last_resume_kind
== resume_step
)
2672 fprintf (stderr
, "GDB wanted to single-step, reporting event.\n");
2673 if (event_child
->stopped_by_watchpoint
)
2674 fprintf (stderr
, "Stopped by watchpoint.\n");
2675 if (gdb_breakpoint_here (event_child
->stop_pc
))
2676 fprintf (stderr
, "Stopped by GDB breakpoint.\n");
2678 fprintf (stderr
, "Hit a non-gdbserver trap event.\n");
2681 /* Alright, we're going to report a stop. */
2683 if (!non_stop
&& !stabilizing_threads
)
2685 /* In all-stop, stop all threads. */
2686 stop_all_lwps (0, NULL
);
2688 /* If we're not waiting for a specific LWP, choose an event LWP
2689 from among those that have had events. Giving equal priority
2690 to all LWPs that have had events helps prevent
2692 if (ptid_equal (ptid
, minus_one_ptid
))
2694 event_child
->status_pending_p
= 1;
2695 event_child
->status_pending
= w
;
2697 select_event_lwp (&event_child
);
2699 event_child
->status_pending_p
= 0;
2700 w
= event_child
->status_pending
;
2703 /* Now that we've selected our final event LWP, cancel any
2704 breakpoints in other LWPs that have hit a GDB breakpoint.
2705 See the comment in cancel_breakpoints_callback to find out
2707 find_inferior (&all_lwps
, cancel_breakpoints_callback
, event_child
);
2709 /* If we were going a step-over, all other threads but the stepping one
2710 had been paused in start_step_over, with their suspend counts
2711 incremented. We don't want to do a full unstop/unpause, because we're
2712 in all-stop mode (so we want threads stopped), but we still need to
2713 unsuspend the other threads, to decrement their `suspended' count
2715 if (step_over_finished
)
2716 unsuspend_all_lwps (event_child
);
2718 /* Stabilize threads (move out of jump pads). */
2719 stabilize_threads ();
2723 /* If we just finished a step-over, then all threads had been
2724 momentarily paused. In all-stop, that's fine, we want
2725 threads stopped by now anyway. In non-stop, we need to
2726 re-resume threads that GDB wanted to be running. */
2727 if (step_over_finished
)
2728 unstop_all_lwps (1, event_child
);
2731 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2733 if (current_inferior
->last_resume_kind
== resume_stop
2734 && WSTOPSIG (w
) == SIGSTOP
)
2736 /* A thread that has been requested to stop by GDB with vCont;t,
2737 and it stopped cleanly, so report as SIG0. The use of
2738 SIGSTOP is an implementation detail. */
2739 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
2741 else if (current_inferior
->last_resume_kind
== resume_stop
2742 && WSTOPSIG (w
) != SIGSTOP
)
2744 /* A thread that has been requested to stop by GDB with vCont;t,
2745 but, it stopped for other reasons. */
2746 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
2750 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
2753 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
2756 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
2757 target_pid_to_str (ptid_of (event_child
)),
2759 ourstatus
->value
.sig
);
2761 return ptid_of (event_child
);
2764 /* Get rid of any pending event in the pipe. */
2766 async_file_flush (void)
2772 ret
= read (linux_event_pipe
[0], &buf
, 1);
2773 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
2776 /* Put something in the pipe, so the event loop wakes up. */
2778 async_file_mark (void)
2782 async_file_flush ();
2785 ret
= write (linux_event_pipe
[1], "+", 1);
2786 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
2788 /* Ignore EAGAIN. If the pipe is full, the event loop will already
2789 be awakened anyway. */
2793 linux_wait (ptid_t ptid
,
2794 struct target_waitstatus
*ourstatus
, int target_options
)
2799 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
2801 /* Flush the async file first. */
2802 if (target_is_async_p ())
2803 async_file_flush ();
2805 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
2807 /* If at least one stop was reported, there may be more. A single
2808 SIGCHLD can signal more than one child stop. */
2809 if (target_is_async_p ()
2810 && (target_options
& TARGET_WNOHANG
) != 0
2811 && !ptid_equal (event_ptid
, null_ptid
))
2817 /* Send a signal to an LWP. */
2820 kill_lwp (unsigned long lwpid
, int signo
)
2822 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2823 fails, then we are not using nptl threads and we should be using kill. */
2827 static int tkill_failed
;
2834 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2835 if (errno
!= ENOSYS
)
2842 return kill (lwpid
, signo
);
2846 linux_stop_lwp (struct lwp_info
*lwp
)
2852 send_sigstop (struct lwp_info
*lwp
)
2856 pid
= lwpid_of (lwp
);
2858 /* If we already have a pending stop signal for this process, don't
2860 if (lwp
->stop_expected
)
2863 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
2869 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
2871 lwp
->stop_expected
= 1;
2872 kill_lwp (pid
, SIGSTOP
);
2876 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
2878 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2880 /* Ignore EXCEPT. */
2891 /* Increment the suspend count of an LWP, and stop it, if not stopped
2894 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
2897 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2899 /* Ignore EXCEPT. */
2905 return send_sigstop_callback (entry
, except
);
2909 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
2911 /* It's dead, really. */
2914 /* Store the exit status for later. */
2915 lwp
->status_pending_p
= 1;
2916 lwp
->status_pending
= wstat
;
2918 /* Prevent trying to stop it. */
2921 /* No further stops are expected from a dead lwp. */
2922 lwp
->stop_expected
= 0;
2926 wait_for_sigstop (struct inferior_list_entry
*entry
)
2928 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2929 struct thread_info
*saved_inferior
;
2938 fprintf (stderr
, "wait_for_sigstop: LWP %ld already stopped\n",
2943 saved_inferior
= current_inferior
;
2944 if (saved_inferior
!= NULL
)
2945 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
2947 saved_tid
= null_ptid
; /* avoid bogus unused warning */
2949 ptid
= lwp
->head
.id
;
2952 fprintf (stderr
, "wait_for_sigstop: pulling one event\n");
2954 pid
= linux_wait_for_event (ptid
, &wstat
, __WALL
);
2956 /* If we stopped with a non-SIGSTOP signal, save it for later
2957 and record the pending SIGSTOP. If the process exited, just
2959 if (WIFSTOPPED (wstat
))
2962 fprintf (stderr
, "LWP %ld stopped with signal %d\n",
2963 lwpid_of (lwp
), WSTOPSIG (wstat
));
2965 if (WSTOPSIG (wstat
) != SIGSTOP
)
2968 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
2969 lwpid_of (lwp
), wstat
);
2971 lwp
->status_pending_p
= 1;
2972 lwp
->status_pending
= wstat
;
2978 fprintf (stderr
, "Process %d exited while stopping LWPs\n", pid
);
2980 lwp
= find_lwp_pid (pid_to_ptid (pid
));
2983 /* Leave this status pending for the next time we're able to
2984 report it. In the mean time, we'll report this lwp as
2985 dead to GDB, so GDB doesn't try to read registers and
2986 memory from it. This can only happen if this was the
2987 last thread of the process; otherwise, PID is removed
2988 from the thread tables before linux_wait_for_event
2990 mark_lwp_dead (lwp
, wstat
);
2994 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
2995 current_inferior
= saved_inferior
;
2999 fprintf (stderr
, "Previously current thread died.\n");
3003 /* We can't change the current inferior behind GDB's back,
3004 otherwise, a subsequent command may apply to the wrong
3006 current_inferior
= NULL
;
3010 /* Set a valid thread as current. */
3011 set_desired_inferior (0);
3016 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3017 move it out, because we need to report the stop event to GDB. For
3018 example, if the user puts a breakpoint in the jump pad, it's
3019 because she wants to debug it. */
3022 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3024 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3025 struct thread_info
*thread
= get_lwp_thread (lwp
);
3027 gdb_assert (lwp
->suspended
== 0);
3028 gdb_assert (lwp
->stopped
);
3030 /* Allow debugging the jump pad, gdb_collect, etc.. */
3031 return (supports_fast_tracepoints ()
3032 && agent_loaded_p ()
3033 && (gdb_breakpoint_here (lwp
->stop_pc
)
3034 || lwp
->stopped_by_watchpoint
3035 || thread
->last_resume_kind
== resume_step
)
3036 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3040 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3042 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3043 struct thread_info
*thread
= get_lwp_thread (lwp
);
3046 gdb_assert (lwp
->suspended
== 0);
3047 gdb_assert (lwp
->stopped
);
3049 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3051 /* Allow debugging the jump pad, gdb_collect, etc. */
3052 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3053 && !lwp
->stopped_by_watchpoint
3054 && thread
->last_resume_kind
!= resume_step
3055 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3059 "LWP %ld needs stabilizing (in jump pad)\n",
3064 lwp
->status_pending_p
= 0;
3065 enqueue_one_deferred_signal (lwp
, wstat
);
3069 "Signal %d for LWP %ld deferred "
3071 WSTOPSIG (*wstat
), lwpid_of (lwp
));
3074 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3081 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3083 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3092 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3093 If SUSPEND, then also increase the suspend count of every LWP,
3097 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3099 /* Should not be called recursively. */
3100 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3102 stopping_threads
= (suspend
3103 ? STOPPING_AND_SUSPENDING_THREADS
3104 : STOPPING_THREADS
);
3107 find_inferior (&all_lwps
, suspend_and_send_sigstop_callback
, except
);
3109 find_inferior (&all_lwps
, send_sigstop_callback
, except
);
3110 for_each_inferior (&all_lwps
, wait_for_sigstop
);
3111 stopping_threads
= NOT_STOPPING_THREADS
;
3114 /* Resume execution of the inferior process.
3115 If STEP is nonzero, single-step it.
3116 If SIGNAL is nonzero, give it that signal. */
3119 linux_resume_one_lwp (struct lwp_info
*lwp
,
3120 int step
, int signal
, siginfo_t
*info
)
3122 struct thread_info
*saved_inferior
;
3123 int fast_tp_collecting
;
3125 if (lwp
->stopped
== 0)
3128 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3130 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3132 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3133 user used the "jump" command, or "set $pc = foo"). */
3134 if (lwp
->stop_pc
!= get_pc (lwp
))
3136 /* Collecting 'while-stepping' actions doesn't make sense
3138 release_while_stepping_state_list (get_lwp_thread (lwp
));
3141 /* If we have pending signals or status, and a new signal, enqueue the
3142 signal. Also enqueue the signal if we are waiting to reinsert a
3143 breakpoint; it will be picked up again below. */
3145 && (lwp
->status_pending_p
3146 || lwp
->pending_signals
!= NULL
3147 || lwp
->bp_reinsert
!= 0
3148 || fast_tp_collecting
))
3150 struct pending_signals
*p_sig
;
3151 p_sig
= xmalloc (sizeof (*p_sig
));
3152 p_sig
->prev
= lwp
->pending_signals
;
3153 p_sig
->signal
= signal
;
3155 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3157 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3158 lwp
->pending_signals
= p_sig
;
3161 if (lwp
->status_pending_p
)
3164 fprintf (stderr
, "Not resuming lwp %ld (%s, signal %d, stop %s);"
3165 " has pending status\n",
3166 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3167 lwp
->stop_expected
? "expected" : "not expected");
3171 saved_inferior
= current_inferior
;
3172 current_inferior
= get_lwp_thread (lwp
);
3175 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
3176 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3177 lwp
->stop_expected
? "expected" : "not expected");
3179 /* This bit needs some thinking about. If we get a signal that
3180 we must report while a single-step reinsert is still pending,
3181 we often end up resuming the thread. It might be better to
3182 (ew) allow a stack of pending events; then we could be sure that
3183 the reinsert happened right away and not lose any signals.
3185 Making this stack would also shrink the window in which breakpoints are
3186 uninserted (see comment in linux_wait_for_lwp) but not enough for
3187 complete correctness, so it won't solve that problem. It may be
3188 worthwhile just to solve this one, however. */
3189 if (lwp
->bp_reinsert
!= 0)
3192 fprintf (stderr
, " pending reinsert at 0x%s\n",
3193 paddress (lwp
->bp_reinsert
));
3195 if (can_hardware_single_step ())
3197 if (fast_tp_collecting
== 0)
3200 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
3202 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
3209 /* Postpone any pending signal. It was enqueued above. */
3213 if (fast_tp_collecting
== 1)
3217 lwp %ld wants to get out of fast tracepoint jump pad (exit-jump-pad-bkpt)\n",
3220 /* Postpone any pending signal. It was enqueued above. */
3223 else if (fast_tp_collecting
== 2)
3227 lwp %ld wants to get out of fast tracepoint jump pad single-stepping\n",
3230 if (can_hardware_single_step ())
3233 fatal ("moving out of jump pad single-stepping"
3234 " not implemented on this target");
3236 /* Postpone any pending signal. It was enqueued above. */
3240 /* If we have while-stepping actions in this thread set it stepping.
3241 If we have a signal to deliver, it may or may not be set to
3242 SIG_IGN, we don't know. Assume so, and allow collecting
3243 while-stepping into a signal handler. A possible smart thing to
3244 do would be to set an internal breakpoint at the signal return
3245 address, continue, and carry on catching this while-stepping
3246 action only when that breakpoint is hit. A future
3248 if (get_lwp_thread (lwp
)->while_stepping
!= NULL
3249 && can_hardware_single_step ())
3253 "lwp %ld has a while-stepping action -> forcing step.\n",
3258 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
3260 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
3261 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
3262 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
3265 /* If we have pending signals, consume one unless we are trying to
3266 reinsert a breakpoint or we're trying to finish a fast tracepoint
3268 if (lwp
->pending_signals
!= NULL
3269 && lwp
->bp_reinsert
== 0
3270 && fast_tp_collecting
== 0)
3272 struct pending_signals
**p_sig
;
3274 p_sig
= &lwp
->pending_signals
;
3275 while ((*p_sig
)->prev
!= NULL
)
3276 p_sig
= &(*p_sig
)->prev
;
3278 signal
= (*p_sig
)->signal
;
3279 if ((*p_sig
)->info
.si_signo
!= 0)
3280 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
3286 if (the_low_target
.prepare_to_resume
!= NULL
)
3287 the_low_target
.prepare_to_resume (lwp
);
3289 regcache_invalidate_one ((struct inferior_list_entry
*)
3290 get_lwp_thread (lwp
));
3293 lwp
->stopped_by_watchpoint
= 0;
3294 lwp
->stepping
= step
;
3295 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0,
3296 /* Coerce to a uintptr_t first to avoid potential gcc warning
3297 of coercing an 8 byte integer to a 4 byte pointer. */
3298 (PTRACE_ARG4_TYPE
) (uintptr_t) signal
);
3300 current_inferior
= saved_inferior
;
3303 /* ESRCH from ptrace either means that the thread was already
3304 running (an error) or that it is gone (a race condition). If
3305 it's gone, we will get a notification the next time we wait,
3306 so we can ignore the error. We could differentiate these
3307 two, but it's tricky without waiting; the thread still exists
3308 as a zombie, so sending it signal 0 would succeed. So just
3313 perror_with_name ("ptrace");
3317 struct thread_resume_array
3319 struct thread_resume
*resume
;
3323 /* This function is called once per thread. We look up the thread
3324 in RESUME_PTR, and mark the thread with a pointer to the appropriate
3327 This algorithm is O(threads * resume elements), but resume elements
3328 is small (and will remain small at least until GDB supports thread
3331 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3333 struct lwp_info
*lwp
;
3334 struct thread_info
*thread
;
3336 struct thread_resume_array
*r
;
3338 thread
= (struct thread_info
*) entry
;
3339 lwp
= get_thread_lwp (thread
);
3342 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3344 ptid_t ptid
= r
->resume
[ndx
].thread
;
3345 if (ptid_equal (ptid
, minus_one_ptid
)
3346 || ptid_equal (ptid
, entry
->id
)
3347 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
3349 || (ptid_get_pid (ptid
) == pid_of (lwp
)
3350 && (ptid_is_pid (ptid
)
3351 || ptid_get_lwp (ptid
) == -1)))
3353 if (r
->resume
[ndx
].kind
== resume_stop
3354 && thread
->last_resume_kind
== resume_stop
)
3357 fprintf (stderr
, "already %s LWP %ld at GDB's request\n",
3358 thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
3366 lwp
->resume
= &r
->resume
[ndx
];
3367 thread
->last_resume_kind
= lwp
->resume
->kind
;
3369 /* If we had a deferred signal to report, dequeue one now.
3370 This can happen if LWP gets more than one signal while
3371 trying to get out of a jump pad. */
3373 && !lwp
->status_pending_p
3374 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3376 lwp
->status_pending_p
= 1;
3380 "Dequeueing deferred signal %d for LWP %ld, "
3381 "leaving status pending.\n",
3382 WSTOPSIG (lwp
->status_pending
), lwpid_of (lwp
));
3389 /* No resume action for this thread. */
3396 /* Set *FLAG_P if this lwp has an interesting status pending. */
3398 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3400 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3402 /* LWPs which will not be resumed are not interesting, because
3403 we might not wait for them next time through linux_wait. */
3404 if (lwp
->resume
== NULL
)
3407 if (lwp
->status_pending_p
)
3408 * (int *) flag_p
= 1;
3413 /* Return 1 if this lwp that GDB wants running is stopped at an
3414 internal breakpoint that we need to step over. It assumes that any
3415 required STOP_PC adjustment has already been propagated to the
3416 inferior's regcache. */
3419 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3421 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3422 struct thread_info
*thread
;
3423 struct thread_info
*saved_inferior
;
3426 /* LWPs which will not be resumed are not interesting, because we
3427 might not wait for them next time through linux_wait. */
3433 "Need step over [LWP %ld]? Ignoring, not stopped\n",
3438 thread
= get_lwp_thread (lwp
);
3440 if (thread
->last_resume_kind
== resume_stop
)
3444 "Need step over [LWP %ld]? Ignoring, should remain stopped\n",
3449 gdb_assert (lwp
->suspended
>= 0);
3455 "Need step over [LWP %ld]? Ignoring, suspended\n",
3460 if (!lwp
->need_step_over
)
3464 "Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
3467 if (lwp
->status_pending_p
)
3471 "Need step over [LWP %ld]? Ignoring, has pending status.\n",
3476 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3480 /* If the PC has changed since we stopped, then don't do anything,
3481 and let the breakpoint/tracepoint be hit. This happens if, for
3482 instance, GDB handled the decr_pc_after_break subtraction itself,
3483 GDB is OOL stepping this thread, or the user has issued a "jump"
3484 command, or poked thread's registers herself. */
3485 if (pc
!= lwp
->stop_pc
)
3489 "Need step over [LWP %ld]? Cancelling, PC was changed. "
3490 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3491 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
3493 lwp
->need_step_over
= 0;
3497 saved_inferior
= current_inferior
;
3498 current_inferior
= thread
;
3500 /* We can only step over breakpoints we know about. */
3501 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3503 /* Don't step over a breakpoint that GDB expects to hit
3504 though. If the condition is being evaluated on the target's side
3505 and it evaluate to false, step over this breakpoint as well. */
3506 if (gdb_breakpoint_here (pc
)
3507 && gdb_condition_true_at_breakpoint (pc
)
3508 && gdb_no_commands_at_breakpoint (pc
))
3512 "Need step over [LWP %ld]? yes, but found"
3513 " GDB breakpoint at 0x%s; skipping step over\n",
3514 lwpid_of (lwp
), paddress (pc
));
3516 current_inferior
= saved_inferior
;
3523 "Need step over [LWP %ld]? yes, "
3524 "found breakpoint at 0x%s\n",
3525 lwpid_of (lwp
), paddress (pc
));
3527 /* We've found an lwp that needs stepping over --- return 1 so
3528 that find_inferior stops looking. */
3529 current_inferior
= saved_inferior
;
3531 /* If the step over is cancelled, this is set again. */
3532 lwp
->need_step_over
= 0;
3537 current_inferior
= saved_inferior
;
3541 "Need step over [LWP %ld]? No, no breakpoint found at 0x%s\n",
3542 lwpid_of (lwp
), paddress (pc
));
3547 /* Start a step-over operation on LWP. When LWP stopped at a
3548 breakpoint, to make progress, we need to remove the breakpoint out
3549 of the way. If we let other threads run while we do that, they may
3550 pass by the breakpoint location and miss hitting it. To avoid
3551 that, a step-over momentarily stops all threads while LWP is
3552 single-stepped while the breakpoint is temporarily uninserted from
3553 the inferior. When the single-step finishes, we reinsert the
3554 breakpoint, and let all threads that are supposed to be running,
3557 On targets that don't support hardware single-step, we don't
3558 currently support full software single-stepping. Instead, we only
3559 support stepping over the thread event breakpoint, by asking the
3560 low target where to place a reinsert breakpoint. Since this
3561 routine assumes the breakpoint being stepped over is a thread event
3562 breakpoint, it usually assumes the return address of the current
3563 function is a good enough place to set the reinsert breakpoint. */
3566 start_step_over (struct lwp_info
*lwp
)
3568 struct thread_info
*saved_inferior
;
3574 "Starting step-over on LWP %ld. Stopping all threads\n",
3577 stop_all_lwps (1, lwp
);
3578 gdb_assert (lwp
->suspended
== 0);
3581 fprintf (stderr
, "Done stopping all threads for step-over.\n");
3583 /* Note, we should always reach here with an already adjusted PC,
3584 either by GDB (if we're resuming due to GDB's request), or by our
3585 caller, if we just finished handling an internal breakpoint GDB
3586 shouldn't care about. */
3589 saved_inferior
= current_inferior
;
3590 current_inferior
= get_lwp_thread (lwp
);
3592 lwp
->bp_reinsert
= pc
;
3593 uninsert_breakpoints_at (pc
);
3594 uninsert_fast_tracepoint_jumps_at (pc
);
3596 if (can_hardware_single_step ())
3602 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3603 set_reinsert_breakpoint (raddr
);
3607 current_inferior
= saved_inferior
;
3609 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3611 /* Require next event from this LWP. */
3612 step_over_bkpt
= lwp
->head
.id
;
3616 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3617 start_step_over, if still there, and delete any reinsert
3618 breakpoints we've set, on non hardware single-step targets. */
3621 finish_step_over (struct lwp_info
*lwp
)
3623 if (lwp
->bp_reinsert
!= 0)
3626 fprintf (stderr
, "Finished step over.\n");
3628 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3629 may be no breakpoint to reinsert there by now. */
3630 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3631 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3633 lwp
->bp_reinsert
= 0;
3635 /* Delete any software-single-step reinsert breakpoints. No
3636 longer needed. We don't have to worry about other threads
3637 hitting this trap, and later not being able to explain it,
3638 because we were stepping over a breakpoint, and we hold all
3639 threads but LWP stopped while doing that. */
3640 if (!can_hardware_single_step ())
3641 delete_reinsert_breakpoints ();
3643 step_over_bkpt
= null_ptid
;
3650 /* This function is called once per thread. We check the thread's resume
3651 request, which will tell us whether to resume, step, or leave the thread
3652 stopped; and what signal, if any, it should be sent.
3654 For threads which we aren't explicitly told otherwise, we preserve
3655 the stepping flag; this is used for stepping over gdbserver-placed
3658 If pending_flags was set in any thread, we queue any needed
3659 signals, since we won't actually resume. We already have a pending
3660 event to report, so we don't need to preserve any step requests;
3661 they should be re-issued if necessary. */
3664 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3666 struct lwp_info
*lwp
;
3667 struct thread_info
*thread
;
3669 int leave_all_stopped
= * (int *) arg
;
3672 thread
= (struct thread_info
*) entry
;
3673 lwp
= get_thread_lwp (thread
);
3675 if (lwp
->resume
== NULL
)
3678 if (lwp
->resume
->kind
== resume_stop
)
3681 fprintf (stderr
, "resume_stop request for LWP %ld\n", lwpid_of (lwp
));
3686 fprintf (stderr
, "stopping LWP %ld\n", lwpid_of (lwp
));
3688 /* Stop the thread, and wait for the event asynchronously,
3689 through the event loop. */
3695 fprintf (stderr
, "already stopped LWP %ld\n",
3698 /* The LWP may have been stopped in an internal event that
3699 was not meant to be notified back to GDB (e.g., gdbserver
3700 breakpoint), so we should be reporting a stop event in
3703 /* If the thread already has a pending SIGSTOP, this is a
3704 no-op. Otherwise, something later will presumably resume
3705 the thread and this will cause it to cancel any pending
3706 operation, due to last_resume_kind == resume_stop. If
3707 the thread already has a pending status to report, we
3708 will still report it the next time we wait - see
3709 status_pending_p_callback. */
3711 /* If we already have a pending signal to report, then
3712 there's no need to queue a SIGSTOP, as this means we're
3713 midway through moving the LWP out of the jumppad, and we
3714 will report the pending signal as soon as that is
3716 if (lwp
->pending_signals_to_report
== NULL
)
3720 /* For stop requests, we're done. */
3722 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3726 /* If this thread which is about to be resumed has a pending status,
3727 then don't resume any threads - we can just report the pending
3728 status. Make sure to queue any signals that would otherwise be
3729 sent. In all-stop mode, we do this decision based on if *any*
3730 thread has a pending status. If there's a thread that needs the
3731 step-over-breakpoint dance, then don't resume any other thread
3732 but that particular one. */
3733 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
3738 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
3740 step
= (lwp
->resume
->kind
== resume_step
);
3741 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
3746 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
3748 /* If we have a new signal, enqueue the signal. */
3749 if (lwp
->resume
->sig
!= 0)
3751 struct pending_signals
*p_sig
;
3752 p_sig
= xmalloc (sizeof (*p_sig
));
3753 p_sig
->prev
= lwp
->pending_signals
;
3754 p_sig
->signal
= lwp
->resume
->sig
;
3755 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3757 /* If this is the same signal we were previously stopped by,
3758 make sure to queue its siginfo. We can ignore the return
3759 value of ptrace; if it fails, we'll skip
3760 PTRACE_SETSIGINFO. */
3761 if (WIFSTOPPED (lwp
->last_status
)
3762 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
3763 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
3765 lwp
->pending_signals
= p_sig
;
3769 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3775 linux_resume (struct thread_resume
*resume_info
, size_t n
)
3777 struct thread_resume_array array
= { resume_info
, n
};
3778 struct lwp_info
*need_step_over
= NULL
;
3780 int leave_all_stopped
;
3782 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
3784 /* If there is a thread which would otherwise be resumed, which has
3785 a pending status, then don't resume any threads - we can just
3786 report the pending status. Make sure to queue any signals that
3787 would otherwise be sent. In non-stop mode, we'll apply this
3788 logic to each thread individually. We consume all pending events
3789 before considering to start a step-over (in all-stop). */
3792 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
3794 /* If there is a thread which would otherwise be resumed, which is
3795 stopped at a breakpoint that needs stepping over, then don't
3796 resume any threads - have it step over the breakpoint with all
3797 other threads stopped, then resume all threads again. Make sure
3798 to queue any signals that would otherwise be delivered or
3800 if (!any_pending
&& supports_breakpoints ())
3802 = (struct lwp_info
*) find_inferior (&all_lwps
,
3803 need_step_over_p
, NULL
);
3805 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
3809 if (need_step_over
!= NULL
)
3810 fprintf (stderr
, "Not resuming all, need step over\n");
3811 else if (any_pending
)
3813 "Not resuming, all-stop and found "
3814 "an LWP with pending status\n");
3816 fprintf (stderr
, "Resuming, no pending status or step over needed\n");
3819 /* Even if we're leaving threads stopped, queue all signals we'd
3820 otherwise deliver. */
3821 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
3824 start_step_over (need_step_over
);
3827 /* This function is called once per thread. We check the thread's
3828 last resume request, which will tell us whether to resume, step, or
3829 leave the thread stopped. Any signal the client requested to be
3830 delivered has already been enqueued at this point.
3832 If any thread that GDB wants running is stopped at an internal
3833 breakpoint that needs stepping over, we start a step-over operation
3834 on that particular thread, and leave all others stopped. */
3837 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3839 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3840 struct thread_info
*thread
;
3848 "proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
3853 fprintf (stderr
, " LWP %ld already running\n", lwpid_of (lwp
));
3857 thread
= get_lwp_thread (lwp
);
3859 if (thread
->last_resume_kind
== resume_stop
3860 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
3863 fprintf (stderr
, " client wants LWP to remain %ld stopped\n",
3868 if (lwp
->status_pending_p
)
3871 fprintf (stderr
, " LWP %ld has pending status, leaving stopped\n",
3876 gdb_assert (lwp
->suspended
>= 0);
3881 fprintf (stderr
, " LWP %ld is suspended\n", lwpid_of (lwp
));
3885 if (thread
->last_resume_kind
== resume_stop
3886 && lwp
->pending_signals_to_report
== NULL
3887 && lwp
->collecting_fast_tracepoint
== 0)
3889 /* We haven't reported this LWP as stopped yet (otherwise, the
3890 last_status.kind check above would catch it, and we wouldn't
3891 reach here. This LWP may have been momentarily paused by a
3892 stop_all_lwps call while handling for example, another LWP's
3893 step-over. In that case, the pending expected SIGSTOP signal
3894 that was queued at vCont;t handling time will have already
3895 been consumed by wait_for_sigstop, and so we need to requeue
3896 another one here. Note that if the LWP already has a SIGSTOP
3897 pending, this is a no-op. */
3901 "Client wants LWP %ld to stop. "
3902 "Making sure it has a SIGSTOP pending\n",
3908 step
= thread
->last_resume_kind
== resume_step
;
3909 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3914 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3916 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3922 gdb_assert (lwp
->suspended
>= 0);
3924 return proceed_one_lwp (entry
, except
);
3927 /* When we finish a step-over, set threads running again. If there's
3928 another thread that may need a step-over, now's the time to start
3929 it. Eventually, we'll move all threads past their breakpoints. */
3932 proceed_all_lwps (void)
3934 struct lwp_info
*need_step_over
;
3936 /* If there is a thread which would otherwise be resumed, which is
3937 stopped at a breakpoint that needs stepping over, then don't
3938 resume any threads - have it step over the breakpoint with all
3939 other threads stopped, then resume all threads again. */
3941 if (supports_breakpoints ())
3944 = (struct lwp_info
*) find_inferior (&all_lwps
,
3945 need_step_over_p
, NULL
);
3947 if (need_step_over
!= NULL
)
3950 fprintf (stderr
, "proceed_all_lwps: found "
3951 "thread %ld needing a step-over\n",
3952 lwpid_of (need_step_over
));
3954 start_step_over (need_step_over
);
3960 fprintf (stderr
, "Proceeding, no step-over needed\n");
3962 find_inferior (&all_lwps
, proceed_one_lwp
, NULL
);
3965 /* Stopped LWPs that the client wanted to be running, that don't have
3966 pending statuses, are set to run again, except for EXCEPT, if not
3967 NULL. This undoes a stop_all_lwps call. */
3970 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
3976 "unstopping all lwps, except=(LWP %ld)\n", lwpid_of (except
));
3979 "unstopping all lwps\n");
3983 find_inferior (&all_lwps
, unsuspend_and_proceed_one_lwp
, except
);
3985 find_inferior (&all_lwps
, proceed_one_lwp
, except
);
3989 #ifdef HAVE_LINUX_REGSETS
3991 #define use_linux_regsets 1
3994 regsets_fetch_inferior_registers (struct regcache
*regcache
)
3996 struct regset_info
*regset
;
3997 int saw_general_regs
= 0;
4001 regset
= target_regsets
;
4003 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4004 while (regset
->size
>= 0)
4009 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
4015 buf
= xmalloc (regset
->size
);
4017 nt_type
= regset
->nt_type
;
4021 iov
.iov_len
= regset
->size
;
4022 data
= (void *) &iov
;
4028 res
= ptrace (regset
->get_request
, pid
,
4029 (PTRACE_ARG3_TYPE
) (long) nt_type
, data
);
4031 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4037 /* If we get EIO on a regset, do not try it again for
4039 disabled_regsets
[regset
- target_regsets
] = 1;
4046 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4051 else if (regset
->type
== GENERAL_REGS
)
4052 saw_general_regs
= 1;
4053 regset
->store_function (regcache
, buf
);
4057 if (saw_general_regs
)
4064 regsets_store_inferior_registers (struct regcache
*regcache
)
4066 struct regset_info
*regset
;
4067 int saw_general_regs
= 0;
4071 regset
= target_regsets
;
4073 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4074 while (regset
->size
>= 0)
4079 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
4085 buf
= xmalloc (regset
->size
);
4087 /* First fill the buffer with the current register set contents,
4088 in case there are any items in the kernel's regset that are
4089 not in gdbserver's regcache. */
4091 nt_type
= regset
->nt_type
;
4095 iov
.iov_len
= regset
->size
;
4096 data
= (void *) &iov
;
4102 res
= ptrace (regset
->get_request
, pid
,
4103 (PTRACE_ARG3_TYPE
) (long) nt_type
, data
);
4105 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4110 /* Then overlay our cached registers on that. */
4111 regset
->fill_function (regcache
, buf
);
4113 /* Only now do we write the register set. */
4115 res
= ptrace (regset
->set_request
, pid
,
4116 (PTRACE_ARG3_TYPE
) (long) nt_type
, data
);
4118 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4126 /* If we get EIO on a regset, do not try it again for
4128 disabled_regsets
[regset
- target_regsets
] = 1;
4132 else if (errno
== ESRCH
)
4134 /* At this point, ESRCH should mean the process is
4135 already gone, in which case we simply ignore attempts
4136 to change its registers. See also the related
4137 comment in linux_resume_one_lwp. */
4143 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4146 else if (regset
->type
== GENERAL_REGS
)
4147 saw_general_regs
= 1;
4151 if (saw_general_regs
)
4157 #else /* !HAVE_LINUX_REGSETS */
4159 #define use_linux_regsets 0
4160 #define regsets_fetch_inferior_registers(regcache) 1
4161 #define regsets_store_inferior_registers(regcache) 1
4165 /* Return 1 if register REGNO is supported by one of the regset ptrace
4166 calls or 0 if it has to be transferred individually. */
4169 linux_register_in_regsets (int regno
)
4171 unsigned char mask
= 1 << (regno
% 8);
4172 size_t index
= regno
/ 8;
4174 return (use_linux_regsets
4175 && (the_low_target
.regset_bitmap
== NULL
4176 || (the_low_target
.regset_bitmap
[index
] & mask
) != 0));
4179 #ifdef HAVE_LINUX_USRREGS
4182 register_addr (int regnum
)
4186 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
4187 error ("Invalid register number %d.", regnum
);
4189 addr
= the_low_target
.regmap
[regnum
];
4194 /* Fetch one register. */
4196 fetch_register (struct regcache
*regcache
, int regno
)
4203 if (regno
>= the_low_target
.num_regs
)
4205 if ((*the_low_target
.cannot_fetch_register
) (regno
))
4208 regaddr
= register_addr (regno
);
4212 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4213 & -sizeof (PTRACE_XFER_TYPE
));
4214 buf
= alloca (size
);
4216 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4217 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4220 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
4221 ptrace (PTRACE_PEEKUSER
, pid
,
4222 /* Coerce to a uintptr_t first to avoid potential gcc warning
4223 of coercing an 8 byte integer to a 4 byte pointer. */
4224 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
, 0);
4225 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4227 error ("reading register %d: %s", regno
, strerror (errno
));
4230 if (the_low_target
.supply_ptrace_register
)
4231 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
4233 supply_register (regcache
, regno
, buf
);
4236 /* Store one register. */
4238 store_register (struct regcache
*regcache
, int regno
)
4245 if (regno
>= the_low_target
.num_regs
)
4247 if ((*the_low_target
.cannot_store_register
) (regno
))
4250 regaddr
= register_addr (regno
);
4254 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4255 & -sizeof (PTRACE_XFER_TYPE
));
4256 buf
= alloca (size
);
4257 memset (buf
, 0, size
);
4259 if (the_low_target
.collect_ptrace_register
)
4260 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
4262 collect_register (regcache
, regno
, buf
);
4264 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4265 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4268 ptrace (PTRACE_POKEUSER
, pid
,
4269 /* Coerce to a uintptr_t first to avoid potential gcc warning
4270 about coercing an 8 byte integer to a 4 byte pointer. */
4271 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
,
4272 (PTRACE_ARG4_TYPE
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
4275 /* At this point, ESRCH should mean the process is
4276 already gone, in which case we simply ignore attempts
4277 to change its registers. See also the related
4278 comment in linux_resume_one_lwp. */
4282 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
4283 error ("writing register %d: %s", regno
, strerror (errno
));
4285 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4289 /* Fetch all registers, or just one, from the child process.
4290 If REGNO is -1, do this for all registers, skipping any that are
4291 assumed to have been retrieved by regsets_fetch_inferior_registers,
4292 unless ALL is non-zero.
4293 Otherwise, REGNO specifies which register (so we can save time). */
4295 usr_fetch_inferior_registers (struct regcache
*regcache
, int regno
, int all
)
4299 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4300 if (all
|| !linux_register_in_regsets (regno
))
4301 fetch_register (regcache
, regno
);
4304 fetch_register (regcache
, regno
);
4307 /* Store our register values back into the inferior.
4308 If REGNO is -1, do this for all registers, skipping any that are
4309 assumed to have been saved by regsets_store_inferior_registers,
4310 unless ALL is non-zero.
4311 Otherwise, REGNO specifies which register (so we can save time). */
4313 usr_store_inferior_registers (struct regcache
*regcache
, int regno
, int all
)
4317 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4318 if (all
|| !linux_register_in_regsets (regno
))
4319 store_register (regcache
, regno
);
4322 store_register (regcache
, regno
);
4325 #else /* !HAVE_LINUX_USRREGS */
4327 #define usr_fetch_inferior_registers(regcache, regno, all) do {} while (0)
4328 #define usr_store_inferior_registers(regcache, regno, all) do {} while (0)
4334 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4341 if (the_low_target
.fetch_register
!= NULL
)
4342 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4343 (*the_low_target
.fetch_register
) (regcache
, regno
);
4345 all
= regsets_fetch_inferior_registers (regcache
);
4346 usr_fetch_inferior_registers (regcache
, -1, all
);
4350 if (the_low_target
.fetch_register
!= NULL
4351 && (*the_low_target
.fetch_register
) (regcache
, regno
))
4354 use_regsets
= linux_register_in_regsets (regno
);
4356 all
= regsets_fetch_inferior_registers (regcache
);
4357 if (!use_regsets
|| all
)
4358 usr_fetch_inferior_registers (regcache
, regno
, 1);
4363 linux_store_registers (struct regcache
*regcache
, int regno
)
4370 all
= regsets_store_inferior_registers (regcache
);
4371 usr_store_inferior_registers (regcache
, regno
, all
);
4375 use_regsets
= linux_register_in_regsets (regno
);
4377 all
= regsets_store_inferior_registers (regcache
);
4378 if (!use_regsets
|| all
)
4379 usr_store_inferior_registers (regcache
, regno
, 1);
4384 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4385 to debugger memory starting at MYADDR. */
4388 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4390 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4391 register PTRACE_XFER_TYPE
*buffer
;
4392 register CORE_ADDR addr
;
4399 /* Try using /proc. Don't bother for one word. */
4400 if (len
>= 3 * sizeof (long))
4404 /* We could keep this file open and cache it - possibly one per
4405 thread. That requires some juggling, but is even faster. */
4406 sprintf (filename
, "/proc/%d/mem", pid
);
4407 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4411 /* If pread64 is available, use it. It's faster if the kernel
4412 supports it (only one syscall), and it's 64-bit safe even on
4413 32-bit platforms (for instance, SPARC debugging a SPARC64
4416 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
4419 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
4420 bytes
= read (fd
, myaddr
, len
);
4427 /* Some data was read, we'll try to get the rest with ptrace. */
4437 /* Round starting address down to longword boundary. */
4438 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4439 /* Round ending address up; get number of longwords that makes. */
4440 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4441 / sizeof (PTRACE_XFER_TYPE
));
4442 /* Allocate buffer of that many longwords. */
4443 buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4445 /* Read all the longwords */
4447 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4449 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4450 about coercing an 8 byte integer to a 4 byte pointer. */
4451 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4452 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4458 /* Copy appropriate bytes out of the buffer. */
4461 i
*= sizeof (PTRACE_XFER_TYPE
);
4462 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
4464 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4471 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4472 memory at MEMADDR. On failure (cannot write to the inferior)
4473 returns the value of errno. */
4476 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4479 /* Round starting address down to longword boundary. */
4480 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4481 /* Round ending address up; get number of longwords that makes. */
4483 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4484 / sizeof (PTRACE_XFER_TYPE
);
4486 /* Allocate buffer of that many longwords. */
4487 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4488 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4490 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4494 /* Dump up to four bytes. */
4495 unsigned int val
= * (unsigned int *) myaddr
;
4501 val
= val
& 0xffffff;
4502 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4503 val
, (long)memaddr
);
4506 /* Fill start and end extra bytes of buffer with existing memory data. */
4509 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4510 about coercing an 8 byte integer to a 4 byte pointer. */
4511 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4512 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4520 = ptrace (PTRACE_PEEKTEXT
, pid
,
4521 /* Coerce to a uintptr_t first to avoid potential gcc warning
4522 about coercing an 8 byte integer to a 4 byte pointer. */
4523 (PTRACE_ARG3_TYPE
) (uintptr_t) (addr
+ (count
- 1)
4524 * sizeof (PTRACE_XFER_TYPE
)),
4530 /* Copy data to be written over corresponding part of buffer. */
4532 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4535 /* Write the entire buffer. */
4537 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4540 ptrace (PTRACE_POKETEXT
, pid
,
4541 /* Coerce to a uintptr_t first to avoid potential gcc warning
4542 about coercing an 8 byte integer to a 4 byte pointer. */
4543 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
4544 (PTRACE_ARG4_TYPE
) buffer
[i
]);
4552 /* Non-zero if the kernel supports PTRACE_O_TRACEFORK. */
4553 static int linux_supports_tracefork_flag
;
4556 linux_enable_event_reporting (int pid
)
4558 if (!linux_supports_tracefork_flag
)
4561 ptrace (PTRACE_SETOPTIONS
, pid
, 0, (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
4564 /* Helper functions for linux_test_for_tracefork, called via clone (). */
4567 linux_tracefork_grandchild (void *arg
)
4572 #define STACK_SIZE 4096
4575 linux_tracefork_child (void *arg
)
4577 ptrace (PTRACE_TRACEME
, 0, 0, 0);
4578 kill (getpid (), SIGSTOP
);
4580 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4583 linux_tracefork_grandchild (NULL
);
4585 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4588 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
4589 CLONE_VM
| SIGCHLD
, NULL
);
4591 clone (linux_tracefork_grandchild
, (char *) arg
+ STACK_SIZE
,
4592 CLONE_VM
| SIGCHLD
, NULL
);
4595 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4600 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
4601 sure that we can enable the option, and that it had the desired
4605 linux_test_for_tracefork (void)
4607 int child_pid
, ret
, status
;
4609 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4610 char *stack
= xmalloc (STACK_SIZE
* 4);
4611 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4613 linux_supports_tracefork_flag
= 0;
4615 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4617 child_pid
= fork ();
4619 linux_tracefork_child (NULL
);
4621 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4623 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
4625 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
4626 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4627 #else /* !__ia64__ */
4628 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
4629 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4630 #endif /* !__ia64__ */
4632 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4634 if (child_pid
== -1)
4635 perror_with_name ("clone");
4637 ret
= my_waitpid (child_pid
, &status
, 0);
4639 perror_with_name ("waitpid");
4640 else if (ret
!= child_pid
)
4641 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
4642 if (! WIFSTOPPED (status
))
4643 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
4645 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
4646 (PTRACE_ARG4_TYPE
) PTRACE_O_TRACEFORK
);
4649 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4652 warning ("linux_test_for_tracefork: failed to kill child");
4656 ret
= my_waitpid (child_pid
, &status
, 0);
4657 if (ret
!= child_pid
)
4658 warning ("linux_test_for_tracefork: failed to wait for killed child");
4659 else if (!WIFSIGNALED (status
))
4660 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
4661 "killed child", status
);
4666 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
4668 warning ("linux_test_for_tracefork: failed to resume child");
4670 ret
= my_waitpid (child_pid
, &status
, 0);
4672 if (ret
== child_pid
&& WIFSTOPPED (status
)
4673 && status
>> 16 == PTRACE_EVENT_FORK
)
4676 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
4677 if (ret
== 0 && second_pid
!= 0)
4681 linux_supports_tracefork_flag
= 1;
4682 my_waitpid (second_pid
, &second_status
, 0);
4683 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
4685 warning ("linux_test_for_tracefork: failed to kill second child");
4686 my_waitpid (second_pid
, &status
, 0);
4690 warning ("linux_test_for_tracefork: unexpected result from waitpid "
4691 "(%d, status 0x%x)", ret
, status
);
4695 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4697 warning ("linux_test_for_tracefork: failed to kill child");
4698 my_waitpid (child_pid
, &status
, 0);
4700 while (WIFSTOPPED (status
));
4702 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4704 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4709 linux_look_up_symbols (void)
4711 #ifdef USE_THREAD_DB
4712 struct process_info
*proc
= current_process ();
4714 if (proc
->private->thread_db
!= NULL
)
4717 /* If the kernel supports tracing forks then it also supports tracing
4718 clones, and then we don't need to use the magic thread event breakpoint
4719 to learn about threads. */
4720 thread_db_init (!linux_supports_tracefork_flag
);
4725 linux_request_interrupt (void)
4727 extern unsigned long signal_pid
;
4729 if (!ptid_equal (cont_thread
, null_ptid
)
4730 && !ptid_equal (cont_thread
, minus_one_ptid
))
4732 struct lwp_info
*lwp
;
4735 lwp
= get_thread_lwp (current_inferior
);
4736 lwpid
= lwpid_of (lwp
);
4737 kill_lwp (lwpid
, SIGINT
);
4740 kill_lwp (signal_pid
, SIGINT
);
4743 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4744 to debugger memory starting at MYADDR. */
4747 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4749 char filename
[PATH_MAX
];
4751 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4753 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4755 fd
= open (filename
, O_RDONLY
);
4759 if (offset
!= (CORE_ADDR
) 0
4760 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4763 n
= read (fd
, myaddr
, len
);
4770 /* These breakpoint and watchpoint related wrapper functions simply
4771 pass on the function call if the target has registered a
4772 corresponding function. */
4775 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
4777 if (the_low_target
.insert_point
!= NULL
)
4778 return the_low_target
.insert_point (type
, addr
, len
);
4780 /* Unsupported (see target.h). */
4785 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
4787 if (the_low_target
.remove_point
!= NULL
)
4788 return the_low_target
.remove_point (type
, addr
, len
);
4790 /* Unsupported (see target.h). */
4795 linux_stopped_by_watchpoint (void)
4797 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4799 return lwp
->stopped_by_watchpoint
;
4803 linux_stopped_data_address (void)
4805 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4807 return lwp
->stopped_data_address
;
4810 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4811 #if ! (defined(PT_TEXT_ADDR) \
4812 || defined(PT_DATA_ADDR) \
4813 || defined(PT_TEXT_END_ADDR))
4814 #if defined(__mcoldfire__)
4815 /* These should really be defined in the kernel's ptrace.h header. */
4816 #define PT_TEXT_ADDR 49*4
4817 #define PT_DATA_ADDR 50*4
4818 #define PT_TEXT_END_ADDR 51*4
4820 #define PT_TEXT_ADDR 220
4821 #define PT_TEXT_END_ADDR 224
4822 #define PT_DATA_ADDR 228
4823 #elif defined(__TMS320C6X__)
4824 #define PT_TEXT_ADDR (0x10000*4)
4825 #define PT_DATA_ADDR (0x10004*4)
4826 #define PT_TEXT_END_ADDR (0x10008*4)
4830 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4831 to tell gdb about. */
4834 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
4836 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
4837 unsigned long text
, text_end
, data
;
4838 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4842 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
4843 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
4844 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
4848 /* Both text and data offsets produced at compile-time (and so
4849 used by gdb) are relative to the beginning of the program,
4850 with the data segment immediately following the text segment.
4851 However, the actual runtime layout in memory may put the data
4852 somewhere else, so when we send gdb a data base-address, we
4853 use the real data base address and subtract the compile-time
4854 data base-address from it (which is just the length of the
4855 text segment). BSS immediately follows data in both
4858 *data_p
= data
- (text_end
- text
);
4868 linux_qxfer_osdata (const char *annex
,
4869 unsigned char *readbuf
, unsigned const char *writebuf
,
4870 CORE_ADDR offset
, int len
)
4872 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
4875 /* Convert a native/host siginfo object, into/from the siginfo in the
4876 layout of the inferiors' architecture. */
4879 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
4883 if (the_low_target
.siginfo_fixup
!= NULL
)
4884 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4886 /* If there was no callback, or the callback didn't do anything,
4887 then just do a straight memcpy. */
4891 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
4893 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
4898 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
4899 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
4903 char inf_siginfo
[sizeof (siginfo_t
)];
4905 if (current_inferior
== NULL
)
4908 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4911 fprintf (stderr
, "%s siginfo for lwp %d.\n",
4912 readbuf
!= NULL
? "Reading" : "Writing",
4915 if (offset
>= sizeof (siginfo
))
4918 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
4921 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4922 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4923 inferior with a 64-bit GDBSERVER should look the same as debugging it
4924 with a 32-bit GDBSERVER, we need to convert it. */
4925 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4927 if (offset
+ len
> sizeof (siginfo
))
4928 len
= sizeof (siginfo
) - offset
;
4930 if (readbuf
!= NULL
)
4931 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4934 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4936 /* Convert back to ptrace layout before flushing it out. */
4937 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4939 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
4946 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4947 so we notice when children change state; as the handler for the
4948 sigsuspend in my_waitpid. */
4951 sigchld_handler (int signo
)
4953 int old_errno
= errno
;
4959 /* fprintf is not async-signal-safe, so call write
4961 if (write (2, "sigchld_handler\n",
4962 sizeof ("sigchld_handler\n") - 1) < 0)
4963 break; /* just ignore */
4967 if (target_is_async_p ())
4968 async_file_mark (); /* trigger a linux_wait */
4974 linux_supports_non_stop (void)
4980 linux_async (int enable
)
4982 int previous
= (linux_event_pipe
[0] != -1);
4985 fprintf (stderr
, "linux_async (%d), previous=%d\n",
4988 if (previous
!= enable
)
4991 sigemptyset (&mask
);
4992 sigaddset (&mask
, SIGCHLD
);
4994 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
4998 if (pipe (linux_event_pipe
) == -1)
4999 fatal ("creating event pipe failed.");
5001 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5002 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5004 /* Register the event loop handler. */
5005 add_file_handler (linux_event_pipe
[0],
5006 handle_target_event
, NULL
);
5008 /* Always trigger a linux_wait. */
5013 delete_file_handler (linux_event_pipe
[0]);
5015 close (linux_event_pipe
[0]);
5016 close (linux_event_pipe
[1]);
5017 linux_event_pipe
[0] = -1;
5018 linux_event_pipe
[1] = -1;
5021 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5028 linux_start_non_stop (int nonstop
)
5030 /* Register or unregister from event-loop accordingly. */
5031 linux_async (nonstop
);
5036 linux_supports_multi_process (void)
5042 linux_supports_disable_randomization (void)
5044 #ifdef HAVE_PERSONALITY
5052 linux_supports_agent (void)
5057 /* Enumerate spufs IDs for process PID. */
5059 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
5065 struct dirent
*entry
;
5067 sprintf (path
, "/proc/%ld/fd", pid
);
5068 dir
= opendir (path
);
5073 while ((entry
= readdir (dir
)) != NULL
)
5079 fd
= atoi (entry
->d_name
);
5083 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
5084 if (stat (path
, &st
) != 0)
5086 if (!S_ISDIR (st
.st_mode
))
5089 if (statfs (path
, &stfs
) != 0)
5091 if (stfs
.f_type
!= SPUFS_MAGIC
)
5094 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
5096 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
5106 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
5107 object type, using the /proc file system. */
5109 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
5110 unsigned const char *writebuf
,
5111 CORE_ADDR offset
, int len
)
5113 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
5118 if (!writebuf
&& !readbuf
)
5126 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5129 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
5130 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5135 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5142 ret
= write (fd
, writebuf
, (size_t) len
);
5144 ret
= read (fd
, readbuf
, (size_t) len
);
5150 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5151 struct target_loadseg
5153 /* Core address to which the segment is mapped. */
5155 /* VMA recorded in the program header. */
5157 /* Size of this segment in memory. */
5161 # if defined PT_GETDSBT
5162 struct target_loadmap
5164 /* Protocol version number, must be zero. */
5166 /* Pointer to the DSBT table, its size, and the DSBT index. */
5167 unsigned *dsbt_table
;
5168 unsigned dsbt_size
, dsbt_index
;
5169 /* Number of segments in this map. */
5171 /* The actual memory map. */
5172 struct target_loadseg segs
[/*nsegs*/];
5174 # define LINUX_LOADMAP PT_GETDSBT
5175 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5176 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5178 struct target_loadmap
5180 /* Protocol version number, must be zero. */
5182 /* Number of segments in this map. */
5184 /* The actual memory map. */
5185 struct target_loadseg segs
[/*nsegs*/];
5187 # define LINUX_LOADMAP PTRACE_GETFDPIC
5188 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5189 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5193 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
5194 unsigned char *myaddr
, unsigned int len
)
5196 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
5198 struct target_loadmap
*data
= NULL
;
5199 unsigned int actual_length
, copy_length
;
5201 if (strcmp (annex
, "exec") == 0)
5202 addr
= (int) LINUX_LOADMAP_EXEC
;
5203 else if (strcmp (annex
, "interp") == 0)
5204 addr
= (int) LINUX_LOADMAP_INTERP
;
5208 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
5214 actual_length
= sizeof (struct target_loadmap
)
5215 + sizeof (struct target_loadseg
) * data
->nsegs
;
5217 if (offset
< 0 || offset
> actual_length
)
5220 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
5221 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
5225 # define linux_read_loadmap NULL
5226 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5229 linux_process_qsupported (const char *query
)
5231 if (the_low_target
.process_qsupported
!= NULL
)
5232 the_low_target
.process_qsupported (query
);
5236 linux_supports_tracepoints (void)
5238 if (*the_low_target
.supports_tracepoints
== NULL
)
5241 return (*the_low_target
.supports_tracepoints
) ();
5245 linux_read_pc (struct regcache
*regcache
)
5247 if (the_low_target
.get_pc
== NULL
)
5250 return (*the_low_target
.get_pc
) (regcache
);
5254 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
5256 gdb_assert (the_low_target
.set_pc
!= NULL
);
5258 (*the_low_target
.set_pc
) (regcache
, pc
);
5262 linux_thread_stopped (struct thread_info
*thread
)
5264 return get_thread_lwp (thread
)->stopped
;
5267 /* This exposes stop-all-threads functionality to other modules. */
5270 linux_pause_all (int freeze
)
5272 stop_all_lwps (freeze
, NULL
);
5275 /* This exposes unstop-all-threads functionality to other gdbserver
5279 linux_unpause_all (int unfreeze
)
5281 unstop_all_lwps (unfreeze
, NULL
);
5285 linux_prepare_to_access_memory (void)
5287 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5290 linux_pause_all (1);
5295 linux_done_accessing_memory (void)
5297 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5300 linux_unpause_all (1);
5304 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5305 CORE_ADDR collector
,
5308 CORE_ADDR
*jump_entry
,
5309 CORE_ADDR
*trampoline
,
5310 ULONGEST
*trampoline_size
,
5311 unsigned char *jjump_pad_insn
,
5312 ULONGEST
*jjump_pad_insn_size
,
5313 CORE_ADDR
*adjusted_insn_addr
,
5314 CORE_ADDR
*adjusted_insn_addr_end
,
5317 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5318 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5319 jump_entry
, trampoline
, trampoline_size
,
5320 jjump_pad_insn
, jjump_pad_insn_size
,
5321 adjusted_insn_addr
, adjusted_insn_addr_end
,
5325 static struct emit_ops
*
5326 linux_emit_ops (void)
5328 if (the_low_target
.emit_ops
!= NULL
)
5329 return (*the_low_target
.emit_ops
) ();
5335 linux_get_min_fast_tracepoint_insn_len (void)
5337 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5340 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5343 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5344 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5346 char filename
[PATH_MAX
];
5348 const int auxv_size
= is_elf64
5349 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5350 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5352 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5354 fd
= open (filename
, O_RDONLY
);
5360 while (read (fd
, buf
, auxv_size
) == auxv_size
5361 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5365 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5367 switch (aux
->a_type
)
5370 *phdr_memaddr
= aux
->a_un
.a_val
;
5373 *num_phdr
= aux
->a_un
.a_val
;
5379 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5381 switch (aux
->a_type
)
5384 *phdr_memaddr
= aux
->a_un
.a_val
;
5387 *num_phdr
= aux
->a_un
.a_val
;
5395 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5397 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5398 "phdr_memaddr = %ld, phdr_num = %d",
5399 (long) *phdr_memaddr
, *num_phdr
);
5406 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5409 get_dynamic (const int pid
, const int is_elf64
)
5411 CORE_ADDR phdr_memaddr
, relocation
;
5413 unsigned char *phdr_buf
;
5414 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5416 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5419 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5420 phdr_buf
= alloca (num_phdr
* phdr_size
);
5422 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5425 /* Compute relocation: it is expected to be 0 for "regular" executables,
5426 non-zero for PIE ones. */
5428 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5431 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5433 if (p
->p_type
== PT_PHDR
)
5434 relocation
= phdr_memaddr
- p
->p_vaddr
;
5438 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5440 if (p
->p_type
== PT_PHDR
)
5441 relocation
= phdr_memaddr
- p
->p_vaddr
;
5444 if (relocation
== -1)
5446 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5447 any real world executables, including PIE executables, have always
5448 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5449 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5450 or present DT_DEBUG anyway (fpc binaries are statically linked).
5452 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5454 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5459 for (i
= 0; i
< num_phdr
; i
++)
5463 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5465 if (p
->p_type
== PT_DYNAMIC
)
5466 return p
->p_vaddr
+ relocation
;
5470 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5472 if (p
->p_type
== PT_DYNAMIC
)
5473 return p
->p_vaddr
+ relocation
;
5480 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5481 can be 0 if the inferior does not yet have the library list initialized.
5482 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
5483 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
5486 get_r_debug (const int pid
, const int is_elf64
)
5488 CORE_ADDR dynamic_memaddr
;
5489 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5490 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5493 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5494 if (dynamic_memaddr
== 0)
5497 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5501 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5502 #ifdef DT_MIPS_RLD_MAP
5506 unsigned char buf
[sizeof (Elf64_Xword
)];
5510 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5512 if (linux_read_memory (dyn
->d_un
.d_val
,
5513 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5518 #endif /* DT_MIPS_RLD_MAP */
5520 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5521 map
= dyn
->d_un
.d_val
;
5523 if (dyn
->d_tag
== DT_NULL
)
5528 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5529 #ifdef DT_MIPS_RLD_MAP
5533 unsigned char buf
[sizeof (Elf32_Word
)];
5537 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5539 if (linux_read_memory (dyn
->d_un
.d_val
,
5540 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5545 #endif /* DT_MIPS_RLD_MAP */
5547 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5548 map
= dyn
->d_un
.d_val
;
5550 if (dyn
->d_tag
== DT_NULL
)
5554 dynamic_memaddr
+= dyn_size
;
5560 /* Read one pointer from MEMADDR in the inferior. */
5563 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5567 /* Go through a union so this works on either big or little endian
5568 hosts, when the inferior's pointer size is smaller than the size
5569 of CORE_ADDR. It is assumed the inferior's endianness is the
5570 same of the superior's. */
5573 CORE_ADDR core_addr
;
5578 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
5581 if (ptr_size
== sizeof (CORE_ADDR
))
5582 *ptr
= addr
.core_addr
;
5583 else if (ptr_size
== sizeof (unsigned int))
5586 gdb_assert_not_reached ("unhandled pointer size");
5591 struct link_map_offsets
5593 /* Offset and size of r_debug.r_version. */
5594 int r_version_offset
;
5596 /* Offset and size of r_debug.r_map. */
5599 /* Offset to l_addr field in struct link_map. */
5602 /* Offset to l_name field in struct link_map. */
5605 /* Offset to l_ld field in struct link_map. */
5608 /* Offset to l_next field in struct link_map. */
5611 /* Offset to l_prev field in struct link_map. */
5615 /* Construct qXfer:libraries-svr4:read reply. */
5618 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5619 unsigned const char *writebuf
,
5620 CORE_ADDR offset
, int len
)
5623 unsigned document_len
;
5624 struct process_info_private
*const priv
= current_process ()->private;
5625 char filename
[PATH_MAX
];
5628 static const struct link_map_offsets lmo_32bit_offsets
=
5630 0, /* r_version offset. */
5631 4, /* r_debug.r_map offset. */
5632 0, /* l_addr offset in link_map. */
5633 4, /* l_name offset in link_map. */
5634 8, /* l_ld offset in link_map. */
5635 12, /* l_next offset in link_map. */
5636 16 /* l_prev offset in link_map. */
5639 static const struct link_map_offsets lmo_64bit_offsets
=
5641 0, /* r_version offset. */
5642 8, /* r_debug.r_map offset. */
5643 0, /* l_addr offset in link_map. */
5644 8, /* l_name offset in link_map. */
5645 16, /* l_ld offset in link_map. */
5646 24, /* l_next offset in link_map. */
5647 32 /* l_prev offset in link_map. */
5649 const struct link_map_offsets
*lmo
;
5650 unsigned int machine
;
5652 if (writebuf
!= NULL
)
5654 if (readbuf
== NULL
)
5657 pid
= lwpid_of (get_thread_lwp (current_inferior
));
5658 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5659 is_elf64
= elf_64_file_p (filename
, &machine
);
5660 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5662 if (priv
->r_debug
== 0)
5663 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5665 /* We failed to find DT_DEBUG. Such situation will not change for this
5666 inferior - do not retry it. Report it to GDB as E01, see for the reasons
5667 at the GDB solib-svr4.c side. */
5668 if (priv
->r_debug
== (CORE_ADDR
) -1)
5671 if (priv
->r_debug
== 0)
5673 document
= xstrdup ("<library-list-svr4 version=\"1.0\"/>\n");
5677 int allocated
= 1024;
5679 const int ptr_size
= is_elf64
? 8 : 4;
5680 CORE_ADDR lm_addr
, lm_prev
, l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5681 int r_version
, header_done
= 0;
5683 document
= xmalloc (allocated
);
5684 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5685 p
= document
+ strlen (document
);
5688 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5689 (unsigned char *) &r_version
,
5690 sizeof (r_version
)) != 0
5693 warning ("unexpected r_debug version %d", r_version
);
5697 if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5698 &lm_addr
, ptr_size
) != 0)
5700 warning ("unable to read r_map from 0x%lx",
5701 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5706 while (read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5707 &l_name
, ptr_size
) == 0
5708 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5709 &l_addr
, ptr_size
) == 0
5710 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5711 &l_ld
, ptr_size
) == 0
5712 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5713 &l_prev
, ptr_size
) == 0
5714 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5715 &l_next
, ptr_size
) == 0)
5717 unsigned char libname
[PATH_MAX
];
5719 if (lm_prev
!= l_prev
)
5721 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5722 (long) lm_prev
, (long) l_prev
);
5726 /* Not checking for error because reading may stop before
5727 we've got PATH_MAX worth of characters. */
5729 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5730 libname
[sizeof (libname
) - 1] = '\0';
5731 if (libname
[0] != '\0')
5733 /* 6x the size for xml_escape_text below. */
5734 size_t len
= 6 * strlen ((char *) libname
);
5739 /* Terminate `<library-list-svr4'. */
5744 while (allocated
< p
- document
+ len
+ 200)
5746 /* Expand to guarantee sufficient storage. */
5747 uintptr_t document_len
= p
- document
;
5749 document
= xrealloc (document
, 2 * allocated
);
5751 p
= document
+ document_len
;
5754 name
= xml_escape_text ((char *) libname
);
5755 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
5756 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5757 name
, (unsigned long) lm_addr
,
5758 (unsigned long) l_addr
, (unsigned long) l_ld
);
5761 else if (lm_prev
== 0)
5763 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5776 /* Empty list; terminate `<library-list-svr4'. */
5780 strcpy (p
, "</library-list-svr4>");
5783 document_len
= strlen (document
);
5784 if (offset
< document_len
)
5785 document_len
-= offset
;
5788 if (len
> document_len
)
5791 memcpy (readbuf
, document
+ offset
, len
);
5797 static struct target_ops linux_target_ops
= {
5798 linux_create_inferior
,
5807 linux_fetch_registers
,
5808 linux_store_registers
,
5809 linux_prepare_to_access_memory
,
5810 linux_done_accessing_memory
,
5813 linux_look_up_symbols
,
5814 linux_request_interrupt
,
5818 linux_stopped_by_watchpoint
,
5819 linux_stopped_data_address
,
5820 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
5825 #ifdef USE_THREAD_DB
5826 thread_db_get_tls_address
,
5831 hostio_last_error_from_errno
,
5834 linux_supports_non_stop
,
5836 linux_start_non_stop
,
5837 linux_supports_multi_process
,
5838 #ifdef USE_THREAD_DB
5839 thread_db_handle_monitor_command
,
5843 linux_common_core_of_thread
,
5845 linux_process_qsupported
,
5846 linux_supports_tracepoints
,
5849 linux_thread_stopped
,
5853 linux_cancel_breakpoints
,
5854 linux_stabilize_threads
,
5855 linux_install_fast_tracepoint_jump_pad
,
5857 linux_supports_disable_randomization
,
5858 linux_get_min_fast_tracepoint_insn_len
,
5859 linux_qxfer_libraries_svr4
,
5860 linux_supports_agent
,
5864 linux_init_signals ()
5866 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5867 to find what the cancel signal actually is. */
5868 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
5869 signal (__SIGRTMIN
+1, SIG_IGN
);
5874 initialize_low (void)
5876 struct sigaction sigchld_action
;
5877 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
5878 set_target_ops (&linux_target_ops
);
5879 set_breakpoint_data (the_low_target
.breakpoint
,
5880 the_low_target
.breakpoint_len
);
5881 linux_init_signals ();
5882 linux_test_for_tracefork ();
5883 linux_ptrace_init_warnings ();
5884 #ifdef HAVE_LINUX_REGSETS
5885 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
5887 disabled_regsets
= xmalloc (num_regsets
);
5890 sigchld_action
.sa_handler
= sigchld_handler
;
5891 sigemptyset (&sigchld_action
.sa_mask
);
5892 sigchld_action
.sa_flags
= SA_RESTART
;
5893 sigaction (SIGCHLD
, &sigchld_action
, NULL
);