1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-1996, 1998-2012 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "linux-osdata.h"
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__))
85 #ifndef HAVE_ELF32_AUXV_T
86 /* Copied from glibc's elf.h. */
89 uint32_t a_type
; /* Entry type */
92 uint32_t a_val
; /* Integer value */
93 /* We use to have pointer elements added here. We cannot do that,
94 though, since it does not work when using 32-bit definitions
95 on 64-bit platforms and vice versa. */
100 #ifndef HAVE_ELF64_AUXV_T
101 /* Copied from glibc's elf.h. */
104 uint64_t a_type
; /* Entry type */
107 uint64_t a_val
; /* Integer value */
108 /* We use to have pointer elements added here. We cannot do that,
109 though, since it does not work when using 32-bit definitions
110 on 64-bit platforms and vice versa. */
115 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
116 representation of the thread ID.
118 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
119 the same as the LWP ID.
121 ``all_processes'' is keyed by the "overall process ID", which
122 GNU/Linux calls tgid, "thread group ID". */
124 struct inferior_list all_lwps
;
126 /* A list of all unknown processes which receive stop signals. Some
127 other process will presumably claim each of these as forked
128 children momentarily. */
130 struct simple_pid_list
132 /* The process ID. */
135 /* The status as reported by waitpid. */
139 struct simple_pid_list
*next
;
141 struct simple_pid_list
*stopped_pids
;
143 /* Trivial list manipulation functions to keep track of a list of new
144 stopped processes. */
147 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
149 struct simple_pid_list
*new_pid
= xmalloc (sizeof (struct simple_pid_list
));
152 new_pid
->status
= status
;
153 new_pid
->next
= *listp
;
158 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
160 struct simple_pid_list
**p
;
162 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
163 if ((*p
)->pid
== pid
)
165 struct simple_pid_list
*next
= (*p
)->next
;
167 *statusp
= (*p
)->status
;
175 enum stopping_threads_kind
177 /* Not stopping threads presently. */
178 NOT_STOPPING_THREADS
,
180 /* Stopping threads. */
183 /* Stopping and suspending threads. */
184 STOPPING_AND_SUSPENDING_THREADS
187 /* This is set while stop_all_lwps is in effect. */
188 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
190 /* FIXME make into a target method? */
191 int using_threads
= 1;
193 /* True if we're presently stabilizing threads (moving them out of
195 static int stabilizing_threads
;
197 /* This flag is true iff we've just created or attached to our first
198 inferior but it has not stopped yet. As soon as it does, we need
199 to call the low target's arch_setup callback. Doing this only on
200 the first inferior avoids reinializing the architecture on every
201 inferior, and avoids messing with the register caches of the
202 already running inferiors. NOTE: this assumes all inferiors under
203 control of gdbserver have the same architecture. */
204 static int new_inferior
;
206 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
207 int step
, int signal
, siginfo_t
*info
);
208 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
209 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
210 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
211 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
212 static void *add_lwp (ptid_t ptid
);
213 static int linux_stopped_by_watchpoint (void);
214 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
215 static void proceed_all_lwps (void);
216 static int finish_step_over (struct lwp_info
*lwp
);
217 static CORE_ADDR
get_stop_pc (struct lwp_info
*lwp
);
218 static int kill_lwp (unsigned long lwpid
, int signo
);
219 static void linux_enable_event_reporting (int pid
);
221 /* True if the low target can hardware single-step. Such targets
222 don't need a BREAKPOINT_REINSERT_ADDR callback. */
225 can_hardware_single_step (void)
227 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
230 /* True if the low target supports memory breakpoints. If so, we'll
231 have a GET_PC implementation. */
234 supports_breakpoints (void)
236 return (the_low_target
.get_pc
!= NULL
);
239 /* Returns true if this target can support fast tracepoints. This
240 does not mean that the in-process agent has been loaded in the
244 supports_fast_tracepoints (void)
246 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
249 struct pending_signals
253 struct pending_signals
*prev
;
256 #ifdef HAVE_LINUX_REGSETS
257 static char *disabled_regsets
;
258 static int num_regsets
;
261 /* The read/write ends of the pipe registered as waitable file in the
263 static int linux_event_pipe
[2] = { -1, -1 };
265 /* True if we're currently in async mode. */
266 #define target_is_async_p() (linux_event_pipe[0] != -1)
268 static void send_sigstop (struct lwp_info
*lwp
);
269 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
271 /* Return non-zero if HEADER is a 64-bit ELF file. */
274 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
276 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
277 && header
->e_ident
[EI_MAG1
] == ELFMAG1
278 && header
->e_ident
[EI_MAG2
] == ELFMAG2
279 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
281 *machine
= header
->e_machine
;
282 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
289 /* Return non-zero if FILE is a 64-bit ELF file,
290 zero if the file is not a 64-bit ELF file,
291 and -1 if the file is not accessible or doesn't exist. */
294 elf_64_file_p (const char *file
, unsigned int *machine
)
299 fd
= open (file
, O_RDONLY
);
303 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
310 return elf_64_header_p (&header
, machine
);
313 /* Accepts an integer PID; Returns true if the executable PID is
314 running is a 64-bit ELF file.. */
317 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
319 char file
[MAXPATHLEN
];
321 sprintf (file
, "/proc/%d/exe", pid
);
322 return elf_64_file_p (file
, machine
);
326 delete_lwp (struct lwp_info
*lwp
)
328 remove_thread (get_lwp_thread (lwp
));
329 remove_inferior (&all_lwps
, &lwp
->head
);
330 free (lwp
->arch_private
);
334 /* Add a process to the common process list, and set its private
337 static struct process_info
*
338 linux_add_process (int pid
, int attached
)
340 struct process_info
*proc
;
342 /* Is this the first process? If so, then set the arch. */
343 if (all_processes
.head
== NULL
)
346 proc
= add_process (pid
, attached
);
347 proc
->private = xcalloc (1, sizeof (*proc
->private));
349 if (the_low_target
.new_process
!= NULL
)
350 proc
->private->arch_private
= the_low_target
.new_process ();
355 /* Wrapper function for waitpid which handles EINTR, and emulates
356 __WALL for systems where that is not available. */
359 my_waitpid (int pid
, int *status
, int flags
)
364 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
368 sigset_t block_mask
, org_mask
, wake_mask
;
371 wnohang
= (flags
& WNOHANG
) != 0;
372 flags
&= ~(__WALL
| __WCLONE
);
375 /* Block all signals while here. This avoids knowing about
376 LinuxThread's signals. */
377 sigfillset (&block_mask
);
378 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
380 /* ... except during the sigsuspend below. */
381 sigemptyset (&wake_mask
);
385 /* Since all signals are blocked, there's no need to check
387 ret
= waitpid (pid
, status
, flags
);
390 if (ret
== -1 && out_errno
!= ECHILD
)
395 if (flags
& __WCLONE
)
397 /* We've tried both flavors now. If WNOHANG is set,
398 there's nothing else to do, just bail out. */
403 fprintf (stderr
, "blocking\n");
405 /* Block waiting for signals. */
406 sigsuspend (&wake_mask
);
412 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
417 ret
= waitpid (pid
, status
, flags
);
418 while (ret
== -1 && errno
== EINTR
);
423 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
424 pid
, flags
, status
? *status
: -1, ret
);
430 /* Handle a GNU/Linux extended wait response. If we see a clone
431 event, we need to add the new LWP to our list (and not report the
432 trap to higher layers). */
435 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
437 int event
= wstat
>> 16;
438 struct lwp_info
*new_lwp
;
440 if (event
== PTRACE_EVENT_CLONE
)
443 unsigned long new_pid
;
446 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), 0, &new_pid
);
448 /* If we haven't already seen the new PID stop, wait for it now. */
449 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
451 /* The new child has a pending SIGSTOP. We can't affect it until it
452 hits the SIGSTOP, but we're already attached. */
454 ret
= my_waitpid (new_pid
, &status
, __WALL
);
457 perror_with_name ("waiting for new child");
458 else if (ret
!= new_pid
)
459 warning ("wait returned unexpected PID %d", ret
);
460 else if (!WIFSTOPPED (status
))
461 warning ("wait returned unexpected status 0x%x", status
);
464 linux_enable_event_reporting (new_pid
);
466 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
467 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
468 add_thread (ptid
, new_lwp
);
470 /* Either we're going to immediately resume the new thread
471 or leave it stopped. linux_resume_one_lwp is a nop if it
472 thinks the thread is currently running, so set this first
473 before calling linux_resume_one_lwp. */
474 new_lwp
->stopped
= 1;
476 /* If we're suspending all threads, leave this one suspended
478 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
479 new_lwp
->suspended
= 1;
481 /* Normally we will get the pending SIGSTOP. But in some cases
482 we might get another signal delivered to the group first.
483 If we do get another signal, be sure not to lose it. */
484 if (WSTOPSIG (status
) == SIGSTOP
)
486 if (stopping_threads
!= NOT_STOPPING_THREADS
)
487 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
489 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
493 new_lwp
->stop_expected
= 1;
495 if (stopping_threads
!= NOT_STOPPING_THREADS
)
497 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
498 new_lwp
->status_pending_p
= 1;
499 new_lwp
->status_pending
= status
;
502 /* Pass the signal on. This is what GDB does - except
503 shouldn't we really report it instead? */
504 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
507 /* Always resume the current thread. If we are stopping
508 threads, it will have a pending SIGSTOP; we may as well
510 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
514 /* Return the PC as read from the regcache of LWP, without any
518 get_pc (struct lwp_info
*lwp
)
520 struct thread_info
*saved_inferior
;
521 struct regcache
*regcache
;
524 if (the_low_target
.get_pc
== NULL
)
527 saved_inferior
= current_inferior
;
528 current_inferior
= get_lwp_thread (lwp
);
530 regcache
= get_thread_regcache (current_inferior
, 1);
531 pc
= (*the_low_target
.get_pc
) (regcache
);
534 fprintf (stderr
, "pc is 0x%lx\n", (long) pc
);
536 current_inferior
= saved_inferior
;
540 /* This function should only be called if LWP got a SIGTRAP.
541 The SIGTRAP could mean several things.
543 On i386, where decr_pc_after_break is non-zero:
544 If we were single-stepping this process using PTRACE_SINGLESTEP,
545 we will get only the one SIGTRAP (even if the instruction we
546 stepped over was a breakpoint). The value of $eip will be the
548 If we continue the process using PTRACE_CONT, we will get a
549 SIGTRAP when we hit a breakpoint. The value of $eip will be
550 the instruction after the breakpoint (i.e. needs to be
551 decremented). If we report the SIGTRAP to GDB, we must also
552 report the undecremented PC. If we cancel the SIGTRAP, we
553 must resume at the decremented PC.
555 (Presumably, not yet tested) On a non-decr_pc_after_break machine
556 with hardware or kernel single-step:
557 If we single-step over a breakpoint instruction, our PC will
558 point at the following instruction. If we continue and hit a
559 breakpoint instruction, our PC will point at the breakpoint
563 get_stop_pc (struct lwp_info
*lwp
)
567 if (the_low_target
.get_pc
== NULL
)
570 stop_pc
= get_pc (lwp
);
572 if (WSTOPSIG (lwp
->last_status
) == SIGTRAP
574 && !lwp
->stopped_by_watchpoint
575 && lwp
->last_status
>> 16 == 0)
576 stop_pc
-= the_low_target
.decr_pc_after_break
;
579 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
585 add_lwp (ptid_t ptid
)
587 struct lwp_info
*lwp
;
589 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
590 memset (lwp
, 0, sizeof (*lwp
));
594 if (the_low_target
.new_thread
!= NULL
)
595 lwp
->arch_private
= the_low_target
.new_thread ();
597 add_inferior_to_list (&all_lwps
, &lwp
->head
);
602 /* Start an inferior process and returns its pid.
603 ALLARGS is a vector of program-name and args. */
606 linux_create_inferior (char *program
, char **allargs
)
608 #ifdef HAVE_PERSONALITY
609 int personality_orig
= 0, personality_set
= 0;
611 struct lwp_info
*new_lwp
;
615 #ifdef HAVE_PERSONALITY
616 if (disable_randomization
)
619 personality_orig
= personality (0xffffffff);
620 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
623 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
625 if (errno
!= 0 || (personality_set
626 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
627 warning ("Error disabling address space randomization: %s",
632 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
638 perror_with_name ("fork");
642 ptrace (PTRACE_TRACEME
, 0, 0, 0);
644 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
645 signal (__SIGRTMIN
+ 1, SIG_DFL
);
650 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
651 stdout to stderr so that inferior i/o doesn't corrupt the connection.
652 Also, redirect stdin to /dev/null. */
653 if (remote_connection_is_stdio ())
656 open ("/dev/null", O_RDONLY
);
658 if (write (2, "stdin/stdout redirected\n",
659 sizeof ("stdin/stdout redirected\n") - 1) < 0)
660 /* Errors ignored. */;
663 execv (program
, allargs
);
665 execvp (program
, allargs
);
667 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
673 #ifdef HAVE_PERSONALITY
677 personality (personality_orig
);
679 warning ("Error restoring address space randomization: %s",
684 linux_add_process (pid
, 0);
686 ptid
= ptid_build (pid
, pid
, 0);
687 new_lwp
= add_lwp (ptid
);
688 add_thread (ptid
, new_lwp
);
689 new_lwp
->must_set_ptrace_flags
= 1;
694 /* Attach to an inferior process. */
697 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
700 struct lwp_info
*new_lwp
;
702 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) != 0)
704 struct buffer buffer
;
708 /* If we fail to attach to an LWP, just warn. */
709 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
710 strerror (errno
), errno
);
715 /* If we fail to attach to a process, report an error. */
716 buffer_init (&buffer
);
717 linux_ptrace_attach_warnings (lwpid
, &buffer
);
718 buffer_grow_str0 (&buffer
, "");
719 error ("%sCannot attach to lwp %ld: %s (%d)", buffer_finish (&buffer
),
720 lwpid
, strerror (errno
), errno
);
724 /* If lwp is the tgid, we handle adding existing threads later.
725 Otherwise we just add lwp without bothering about any other
727 ptid
= ptid_build (lwpid
, lwpid
, 0);
730 /* Note that extracting the pid from the current inferior is
731 safe, since we're always called in the context of the same
732 process as this new thread. */
733 int pid
= pid_of (get_thread_lwp (current_inferior
));
734 ptid
= ptid_build (pid
, lwpid
, 0);
737 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
738 add_thread (ptid
, new_lwp
);
740 /* We need to wait for SIGSTOP before being able to make the next
741 ptrace call on this LWP. */
742 new_lwp
->must_set_ptrace_flags
= 1;
744 if (linux_proc_pid_is_stopped (lwpid
))
748 "Attached to a stopped process\n");
750 /* The process is definitely stopped. It is in a job control
751 stop, unless the kernel predates the TASK_STOPPED /
752 TASK_TRACED distinction, in which case it might be in a
753 ptrace stop. Make sure it is in a ptrace stop; from there we
754 can kill it, signal it, et cetera.
756 First make sure there is a pending SIGSTOP. Since we are
757 already attached, the process can not transition from stopped
758 to running without a PTRACE_CONT; so we know this signal will
759 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
760 probably already in the queue (unless this kernel is old
761 enough to use TASK_STOPPED for ptrace stops); but since
762 SIGSTOP is not an RT signal, it can only be queued once. */
763 kill_lwp (lwpid
, SIGSTOP
);
765 /* Finally, resume the stopped process. This will deliver the
766 SIGSTOP (or a higher priority signal, just like normal
767 PTRACE_ATTACH), which we'll catch later on. */
768 ptrace (PTRACE_CONT
, lwpid
, 0, 0);
771 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
774 There are several cases to consider here:
776 1) gdbserver has already attached to the process and is being notified
777 of a new thread that is being created.
778 In this case we should ignore that SIGSTOP and resume the
779 process. This is handled below by setting stop_expected = 1,
780 and the fact that add_thread sets last_resume_kind ==
783 2) This is the first thread (the process thread), and we're attaching
784 to it via attach_inferior.
785 In this case we want the process thread to stop.
786 This is handled by having linux_attach set last_resume_kind ==
787 resume_stop after we return.
789 If the pid we are attaching to is also the tgid, we attach to and
790 stop all the existing threads. Otherwise, we attach to pid and
791 ignore any other threads in the same group as this pid.
793 3) GDB is connecting to gdbserver and is requesting an enumeration of all
795 In this case we want the thread to stop.
796 FIXME: This case is currently not properly handled.
797 We should wait for the SIGSTOP but don't. Things work apparently
798 because enough time passes between when we ptrace (ATTACH) and when
799 gdb makes the next ptrace call on the thread.
801 On the other hand, if we are currently trying to stop all threads, we
802 should treat the new thread as if we had sent it a SIGSTOP. This works
803 because we are guaranteed that the add_lwp call above added us to the
804 end of the list, and so the new thread has not yet reached
805 wait_for_sigstop (but will). */
806 new_lwp
->stop_expected
= 1;
810 linux_attach_lwp (unsigned long lwpid
)
812 linux_attach_lwp_1 (lwpid
, 0);
815 /* Attach to PID. If PID is the tgid, attach to it and all
819 linux_attach (unsigned long pid
)
821 /* Attach to PID. We will check for other threads
823 linux_attach_lwp_1 (pid
, 1);
824 linux_add_process (pid
, 1);
828 struct thread_info
*thread
;
830 /* Don't ignore the initial SIGSTOP if we just attached to this
831 process. It will be collected by wait shortly. */
832 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
833 thread
->last_resume_kind
= resume_stop
;
836 if (linux_proc_get_tgid (pid
) == pid
)
841 sprintf (pathname
, "/proc/%ld/task", pid
);
843 dir
= opendir (pathname
);
847 fprintf (stderr
, "Could not open /proc/%ld/task.\n", pid
);
852 /* At this point we attached to the tgid. Scan the task for
855 int new_threads_found
;
859 while (iterations
< 2)
861 new_threads_found
= 0;
862 /* Add all the other threads. While we go through the
863 threads, new threads may be spawned. Cycle through
864 the list of threads until we have done two iterations without
865 finding new threads. */
866 while ((dp
= readdir (dir
)) != NULL
)
869 lwp
= strtoul (dp
->d_name
, NULL
, 10);
871 /* Is this a new thread? */
873 && find_thread_ptid (ptid_build (pid
, lwp
, 0)) == NULL
)
875 linux_attach_lwp_1 (lwp
, 0);
880 Found and attached to new lwp %ld\n", lwp
);
884 if (!new_threads_found
)
905 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
907 struct counter
*counter
= args
;
909 if (ptid_get_pid (entry
->id
) == counter
->pid
)
911 if (++counter
->count
> 1)
919 last_thread_of_process_p (struct thread_info
*thread
)
921 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
922 int pid
= ptid_get_pid (ptid
);
923 struct counter counter
= { pid
, 0 };
925 return (find_inferior (&all_threads
,
926 second_thread_of_pid_p
, &counter
) == NULL
);
932 linux_kill_one_lwp (struct lwp_info
*lwp
)
934 int pid
= lwpid_of (lwp
);
936 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
937 there is no signal context, and ptrace(PTRACE_KILL) (or
938 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
939 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
940 alternative is to kill with SIGKILL. We only need one SIGKILL
941 per process, not one for each thread. But since we still support
942 linuxthreads, and we also support debugging programs using raw
943 clone without CLONE_THREAD, we send one for each thread. For
944 years, we used PTRACE_KILL only, so we're being a bit paranoid
945 about some old kernels where PTRACE_KILL might work better
946 (dubious if there are any such, but that's why it's paranoia), so
947 we try SIGKILL first, PTRACE_KILL second, and so we're fine
954 "LKL: kill (SIGKILL) %s, 0, 0 (%s)\n",
955 target_pid_to_str (ptid_of (lwp
)),
956 errno
? strerror (errno
) : "OK");
959 ptrace (PTRACE_KILL
, pid
, 0, 0);
962 "LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
963 target_pid_to_str (ptid_of (lwp
)),
964 errno
? strerror (errno
) : "OK");
967 /* Callback for `find_inferior'. Kills an lwp of a given process,
968 except the leader. */
971 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
973 struct thread_info
*thread
= (struct thread_info
*) entry
;
974 struct lwp_info
*lwp
= get_thread_lwp (thread
);
976 int pid
= * (int *) args
;
978 if (ptid_get_pid (entry
->id
) != pid
)
981 /* We avoid killing the first thread here, because of a Linux kernel (at
982 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
983 the children get a chance to be reaped, it will remain a zombie
986 if (lwpid_of (lwp
) == pid
)
989 fprintf (stderr
, "lkop: is last of process %s\n",
990 target_pid_to_str (entry
->id
));
996 linux_kill_one_lwp (lwp
);
998 /* Make sure it died. The loop is most likely unnecessary. */
999 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
1000 } while (pid
> 0 && WIFSTOPPED (wstat
));
1006 linux_kill (int pid
)
1008 struct process_info
*process
;
1009 struct lwp_info
*lwp
;
1013 process
= find_process_pid (pid
);
1014 if (process
== NULL
)
1017 /* If we're killing a running inferior, make sure it is stopped
1018 first, as PTRACE_KILL will not work otherwise. */
1019 stop_all_lwps (0, NULL
);
1021 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1023 /* See the comment in linux_kill_one_lwp. We did not kill the first
1024 thread in the list, so do so now. */
1025 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1030 fprintf (stderr
, "lk_1: cannot find lwp %ld, for pid: %d\n",
1031 lwpid_of (lwp
), pid
);
1036 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
1037 lwpid_of (lwp
), pid
);
1041 linux_kill_one_lwp (lwp
);
1043 /* Make sure it died. The loop is most likely unnecessary. */
1044 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
1045 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
1048 the_target
->mourn (process
);
1050 /* Since we presently can only stop all lwps of all processes, we
1051 need to unstop lwps of other processes. */
1052 unstop_all_lwps (0, NULL
);
1056 /* Get pending signal of THREAD, for detaching purposes. This is the
1057 signal the thread last stopped for, which we need to deliver to the
1058 thread when detaching, otherwise, it'd be suppressed/lost. */
1061 get_detach_signal (struct thread_info
*thread
)
1063 enum target_signal signo
= TARGET_SIGNAL_0
;
1065 struct lwp_info
*lp
= get_thread_lwp (thread
);
1067 if (lp
->status_pending_p
)
1068 status
= lp
->status_pending
;
1071 /* If the thread had been suspended by gdbserver, and it stopped
1072 cleanly, then it'll have stopped with SIGSTOP. But we don't
1073 want to deliver that SIGSTOP. */
1074 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1075 || thread
->last_status
.value
.sig
== TARGET_SIGNAL_0
)
1078 /* Otherwise, we may need to deliver the signal we
1080 status
= lp
->last_status
;
1083 if (!WIFSTOPPED (status
))
1087 "GPS: lwp %s hasn't stopped: no pending signal\n",
1088 target_pid_to_str (ptid_of (lp
)));
1092 /* Extended wait statuses aren't real SIGTRAPs. */
1093 if (WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
1097 "GPS: lwp %s had stopped with extended "
1098 "status: no pending signal\n",
1099 target_pid_to_str (ptid_of (lp
)));
1103 signo
= target_signal_from_host (WSTOPSIG (status
));
1105 if (program_signals_p
&& !program_signals
[signo
])
1109 "GPS: lwp %s had signal %s, but it is in nopass state\n",
1110 target_pid_to_str (ptid_of (lp
)),
1111 target_signal_to_string (signo
));
1114 else if (!program_signals_p
1115 /* If we have no way to know which signals GDB does not
1116 want to have passed to the program, assume
1117 SIGTRAP/SIGINT, which is GDB's default. */
1118 && (signo
== TARGET_SIGNAL_TRAP
|| signo
== TARGET_SIGNAL_INT
))
1122 "GPS: lwp %s had signal %s, "
1123 "but we don't know if we should pass it. Default to not.\n",
1124 target_pid_to_str (ptid_of (lp
)),
1125 target_signal_to_string (signo
));
1132 "GPS: lwp %s has pending signal %s: delivering it.\n",
1133 target_pid_to_str (ptid_of (lp
)),
1134 target_signal_to_string (signo
));
1136 return WSTOPSIG (status
);
1141 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1143 struct thread_info
*thread
= (struct thread_info
*) entry
;
1144 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1145 int pid
= * (int *) args
;
1148 if (ptid_get_pid (entry
->id
) != pid
)
1151 /* If there is a pending SIGSTOP, get rid of it. */
1152 if (lwp
->stop_expected
)
1156 "Sending SIGCONT to %s\n",
1157 target_pid_to_str (ptid_of (lwp
)));
1159 kill_lwp (lwpid_of (lwp
), SIGCONT
);
1160 lwp
->stop_expected
= 0;
1163 /* Flush any pending changes to the process's registers. */
1164 regcache_invalidate_one ((struct inferior_list_entry
*)
1165 get_lwp_thread (lwp
));
1167 /* Pass on any pending signal for this thread. */
1168 sig
= get_detach_signal (thread
);
1170 /* Finally, let it resume. */
1171 if (the_low_target
.prepare_to_resume
!= NULL
)
1172 the_low_target
.prepare_to_resume (lwp
);
1173 if (ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0,
1174 (PTRACE_ARG4_TYPE
) (long) sig
) < 0)
1175 error (_("Can't detach %s: %s"),
1176 target_pid_to_str (ptid_of (lwp
)),
1184 linux_detach (int pid
)
1186 struct process_info
*process
;
1188 process
= find_process_pid (pid
);
1189 if (process
== NULL
)
1192 /* Stop all threads before detaching. First, ptrace requires that
1193 the thread is stopped to sucessfully detach. Second, thread_db
1194 may need to uninstall thread event breakpoints from memory, which
1195 only works with a stopped process anyway. */
1196 stop_all_lwps (0, NULL
);
1198 #ifdef USE_THREAD_DB
1199 thread_db_detach (process
);
1202 /* Stabilize threads (move out of jump pads). */
1203 stabilize_threads ();
1205 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1207 the_target
->mourn (process
);
1209 /* Since we presently can only stop all lwps of all processes, we
1210 need to unstop lwps of other processes. */
1211 unstop_all_lwps (0, NULL
);
1215 /* Remove all LWPs that belong to process PROC from the lwp list. */
1218 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1220 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1221 struct process_info
*process
= proc
;
1223 if (pid_of (lwp
) == pid_of (process
))
1230 linux_mourn (struct process_info
*process
)
1232 struct process_info_private
*priv
;
1234 #ifdef USE_THREAD_DB
1235 thread_db_mourn (process
);
1238 find_inferior (&all_lwps
, delete_lwp_callback
, process
);
1240 /* Freeing all private data. */
1241 priv
= process
->private;
1242 free (priv
->arch_private
);
1244 process
->private = NULL
;
1246 remove_process (process
);
1250 linux_join (int pid
)
1255 ret
= my_waitpid (pid
, &status
, 0);
1256 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1258 } while (ret
!= -1 || errno
!= ECHILD
);
1261 /* Return nonzero if the given thread is still alive. */
1263 linux_thread_alive (ptid_t ptid
)
1265 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1267 /* We assume we always know if a thread exits. If a whole process
1268 exited but we still haven't been able to report it to GDB, we'll
1269 hold on to the last lwp of the dead process. */
1276 /* Return 1 if this lwp has an interesting status pending. */
1278 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1280 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1281 ptid_t ptid
= * (ptid_t
*) arg
;
1282 struct thread_info
*thread
;
1284 /* Check if we're only interested in events from a specific process
1286 if (!ptid_equal (minus_one_ptid
, ptid
)
1287 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
1290 thread
= get_lwp_thread (lwp
);
1292 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1293 report any status pending the LWP may have. */
1294 if (thread
->last_resume_kind
== resume_stop
1295 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1298 return lwp
->status_pending_p
;
1302 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1304 ptid_t ptid
= *(ptid_t
*) data
;
1307 if (ptid_get_lwp (ptid
) != 0)
1308 lwp
= ptid_get_lwp (ptid
);
1310 lwp
= ptid_get_pid (ptid
);
1312 if (ptid_get_lwp (entry
->id
) == lwp
)
1319 find_lwp_pid (ptid_t ptid
)
1321 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
1324 static struct lwp_info
*
1325 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
1328 int to_wait_for
= -1;
1329 struct lwp_info
*child
= NULL
;
1332 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1334 if (ptid_equal (ptid
, minus_one_ptid
))
1335 to_wait_for
= -1; /* any child */
1337 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1343 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1344 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1347 perror_with_name ("waitpid");
1350 && (!WIFSTOPPED (*wstatp
)
1351 || (WSTOPSIG (*wstatp
) != 32
1352 && WSTOPSIG (*wstatp
) != 33)))
1353 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1355 child
= find_lwp_pid (pid_to_ptid (ret
));
1357 /* If we didn't find a process, one of two things presumably happened:
1358 - A process we started and then detached from has exited. Ignore it.
1359 - A process we are controlling has forked and the new child's stop
1360 was reported to us by the kernel. Save its PID. */
1361 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1363 add_to_pid_list (&stopped_pids
, ret
, *wstatp
);
1366 else if (child
== NULL
)
1371 child
->last_status
= *wstatp
;
1373 /* Architecture-specific setup after inferior is running.
1374 This needs to happen after we have attached to the inferior
1375 and it is stopped for the first time, but before we access
1376 any inferior registers. */
1379 the_low_target
.arch_setup ();
1380 #ifdef HAVE_LINUX_REGSETS
1381 memset (disabled_regsets
, 0, num_regsets
);
1386 /* Fetch the possibly triggered data watchpoint info and store it in
1389 On some archs, like x86, that use debug registers to set
1390 watchpoints, it's possible that the way to know which watched
1391 address trapped, is to check the register that is used to select
1392 which address to watch. Problem is, between setting the
1393 watchpoint and reading back which data address trapped, the user
1394 may change the set of watchpoints, and, as a consequence, GDB
1395 changes the debug registers in the inferior. To avoid reading
1396 back a stale stopped-data-address when that happens, we cache in
1397 LP the fact that a watchpoint trapped, and the corresponding data
1398 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1399 changes the debug registers meanwhile, we have the cached data we
1402 if (WIFSTOPPED (*wstatp
) && WSTOPSIG (*wstatp
) == SIGTRAP
)
1404 if (the_low_target
.stopped_by_watchpoint
== NULL
)
1406 child
->stopped_by_watchpoint
= 0;
1410 struct thread_info
*saved_inferior
;
1412 saved_inferior
= current_inferior
;
1413 current_inferior
= get_lwp_thread (child
);
1415 child
->stopped_by_watchpoint
1416 = the_low_target
.stopped_by_watchpoint ();
1418 if (child
->stopped_by_watchpoint
)
1420 if (the_low_target
.stopped_data_address
!= NULL
)
1421 child
->stopped_data_address
1422 = the_low_target
.stopped_data_address ();
1424 child
->stopped_data_address
= 0;
1427 current_inferior
= saved_inferior
;
1431 /* Store the STOP_PC, with adjustment applied. This depends on the
1432 architecture being defined already (so that CHILD has a valid
1433 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1435 if (WIFSTOPPED (*wstatp
))
1436 child
->stop_pc
= get_stop_pc (child
);
1439 && WIFSTOPPED (*wstatp
)
1440 && the_low_target
.get_pc
!= NULL
)
1442 struct thread_info
*saved_inferior
= current_inferior
;
1443 struct regcache
*regcache
;
1446 current_inferior
= get_lwp_thread (child
);
1447 regcache
= get_thread_regcache (current_inferior
, 1);
1448 pc
= (*the_low_target
.get_pc
) (regcache
);
1449 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1450 current_inferior
= saved_inferior
;
1456 /* This function should only be called if the LWP got a SIGTRAP.
1458 Handle any tracepoint steps or hits. Return true if a tracepoint
1459 event was handled, 0 otherwise. */
1462 handle_tracepoints (struct lwp_info
*lwp
)
1464 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1465 int tpoint_related_event
= 0;
1467 /* If this tracepoint hit causes a tracing stop, we'll immediately
1468 uninsert tracepoints. To do this, we temporarily pause all
1469 threads, unpatch away, and then unpause threads. We need to make
1470 sure the unpausing doesn't resume LWP too. */
1473 /* And we need to be sure that any all-threads-stopping doesn't try
1474 to move threads out of the jump pads, as it could deadlock the
1475 inferior (LWP could be in the jump pad, maybe even holding the
1478 /* Do any necessary step collect actions. */
1479 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1481 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1483 /* See if we just hit a tracepoint and do its main collect
1485 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1489 gdb_assert (lwp
->suspended
== 0);
1490 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1492 if (tpoint_related_event
)
1495 fprintf (stderr
, "got a tracepoint event\n");
1502 /* Convenience wrapper. Returns true if LWP is presently collecting a
1506 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1507 struct fast_tpoint_collect_status
*status
)
1509 CORE_ADDR thread_area
;
1511 if (the_low_target
.get_thread_area
== NULL
)
1514 /* Get the thread area address. This is used to recognize which
1515 thread is which when tracing with the in-process agent library.
1516 We don't read anything from the address, and treat it as opaque;
1517 it's the address itself that we assume is unique per-thread. */
1518 if ((*the_low_target
.get_thread_area
) (lwpid_of (lwp
), &thread_area
) == -1)
1521 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1524 /* The reason we resume in the caller, is because we want to be able
1525 to pass lwp->status_pending as WSTAT, and we need to clear
1526 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1527 refuses to resume. */
1530 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1532 struct thread_info
*saved_inferior
;
1534 saved_inferior
= current_inferior
;
1535 current_inferior
= get_lwp_thread (lwp
);
1538 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1539 && supports_fast_tracepoints ()
1540 && agent_loaded_p ())
1542 struct fast_tpoint_collect_status status
;
1547 Checking whether LWP %ld needs to move out of the jump pad.\n",
1550 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1553 || (WSTOPSIG (*wstat
) != SIGILL
1554 && WSTOPSIG (*wstat
) != SIGFPE
1555 && WSTOPSIG (*wstat
) != SIGSEGV
1556 && WSTOPSIG (*wstat
) != SIGBUS
))
1558 lwp
->collecting_fast_tracepoint
= r
;
1562 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1564 /* Haven't executed the original instruction yet.
1565 Set breakpoint there, and wait till it's hit,
1566 then single-step until exiting the jump pad. */
1567 lwp
->exit_jump_pad_bkpt
1568 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1573 Checking whether LWP %ld needs to move out of the jump pad...it does\n",
1575 current_inferior
= saved_inferior
;
1582 /* If we get a synchronous signal while collecting, *and*
1583 while executing the (relocated) original instruction,
1584 reset the PC to point at the tpoint address, before
1585 reporting to GDB. Otherwise, it's an IPA lib bug: just
1586 report the signal to GDB, and pray for the best. */
1588 lwp
->collecting_fast_tracepoint
= 0;
1591 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1592 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1595 struct regcache
*regcache
;
1597 /* The si_addr on a few signals references the address
1598 of the faulting instruction. Adjust that as
1600 if ((WSTOPSIG (*wstat
) == SIGILL
1601 || WSTOPSIG (*wstat
) == SIGFPE
1602 || WSTOPSIG (*wstat
) == SIGBUS
1603 || WSTOPSIG (*wstat
) == SIGSEGV
)
1604 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &info
) == 0
1605 /* Final check just to make sure we don't clobber
1606 the siginfo of non-kernel-sent signals. */
1607 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1609 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1610 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &info
);
1613 regcache
= get_thread_regcache (get_lwp_thread (lwp
), 1);
1614 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1615 lwp
->stop_pc
= status
.tpoint_addr
;
1617 /* Cancel any fast tracepoint lock this thread was
1619 force_unlock_trace_buffer ();
1622 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1626 "Cancelling fast exit-jump-pad: removing bkpt. "
1627 "stopping all threads momentarily.\n");
1629 stop_all_lwps (1, lwp
);
1630 cancel_breakpoints ();
1632 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1633 lwp
->exit_jump_pad_bkpt
= NULL
;
1635 unstop_all_lwps (1, lwp
);
1637 gdb_assert (lwp
->suspended
>= 0);
1644 Checking whether LWP %ld needs to move out of the jump pad...no\n",
1647 current_inferior
= saved_inferior
;
1651 /* Enqueue one signal in the "signals to report later when out of the
1655 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1657 struct pending_signals
*p_sig
;
1661 Deferring signal %d for LWP %ld.\n", WSTOPSIG (*wstat
), lwpid_of (lwp
));
1665 struct pending_signals
*sig
;
1667 for (sig
= lwp
->pending_signals_to_report
;
1671 " Already queued %d\n",
1674 fprintf (stderr
, " (no more currently queued signals)\n");
1677 /* Don't enqueue non-RT signals if they are already in the deferred
1678 queue. (SIGSTOP being the easiest signal to see ending up here
1680 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1682 struct pending_signals
*sig
;
1684 for (sig
= lwp
->pending_signals_to_report
;
1688 if (sig
->signal
== WSTOPSIG (*wstat
))
1692 "Not requeuing already queued non-RT signal %d"
1701 p_sig
= xmalloc (sizeof (*p_sig
));
1702 p_sig
->prev
= lwp
->pending_signals_to_report
;
1703 p_sig
->signal
= WSTOPSIG (*wstat
);
1704 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1705 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
1707 lwp
->pending_signals_to_report
= p_sig
;
1710 /* Dequeue one signal from the "signals to report later when out of
1711 the jump pad" list. */
1714 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1716 if (lwp
->pending_signals_to_report
!= NULL
)
1718 struct pending_signals
**p_sig
;
1720 p_sig
= &lwp
->pending_signals_to_report
;
1721 while ((*p_sig
)->prev
!= NULL
)
1722 p_sig
= &(*p_sig
)->prev
;
1724 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1725 if ((*p_sig
)->info
.si_signo
!= 0)
1726 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
1731 fprintf (stderr
, "Reporting deferred signal %d for LWP %ld.\n",
1732 WSTOPSIG (*wstat
), lwpid_of (lwp
));
1736 struct pending_signals
*sig
;
1738 for (sig
= lwp
->pending_signals_to_report
;
1742 " Still queued %d\n",
1745 fprintf (stderr
, " (no more queued signals)\n");
1754 /* Arrange for a breakpoint to be hit again later. We don't keep the
1755 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1756 will handle the current event, eventually we will resume this LWP,
1757 and this breakpoint will trap again. */
1760 cancel_breakpoint (struct lwp_info
*lwp
)
1762 struct thread_info
*saved_inferior
;
1764 /* There's nothing to do if we don't support breakpoints. */
1765 if (!supports_breakpoints ())
1768 /* breakpoint_at reads from current inferior. */
1769 saved_inferior
= current_inferior
;
1770 current_inferior
= get_lwp_thread (lwp
);
1772 if ((*the_low_target
.breakpoint_at
) (lwp
->stop_pc
))
1776 "CB: Push back breakpoint for %s\n",
1777 target_pid_to_str (ptid_of (lwp
)));
1779 /* Back up the PC if necessary. */
1780 if (the_low_target
.decr_pc_after_break
)
1782 struct regcache
*regcache
1783 = get_thread_regcache (current_inferior
, 1);
1784 (*the_low_target
.set_pc
) (regcache
, lwp
->stop_pc
);
1787 current_inferior
= saved_inferior
;
1794 "CB: No breakpoint found at %s for [%s]\n",
1795 paddress (lwp
->stop_pc
),
1796 target_pid_to_str (ptid_of (lwp
)));
1799 current_inferior
= saved_inferior
;
1803 /* When the event-loop is doing a step-over, this points at the thread
1805 ptid_t step_over_bkpt
;
1807 /* Wait for an event from child PID. If PID is -1, wait for any
1808 child. Store the stop status through the status pointer WSTAT.
1809 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1810 event was found and OPTIONS contains WNOHANG. Return the PID of
1811 the stopped child otherwise. */
1814 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1816 struct lwp_info
*event_child
, *requested_child
;
1820 requested_child
= NULL
;
1822 /* Check for a lwp with a pending status. */
1824 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
1826 event_child
= (struct lwp_info
*)
1827 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1828 if (debug_threads
&& event_child
)
1829 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1833 requested_child
= find_lwp_pid (ptid
);
1835 if (stopping_threads
== NOT_STOPPING_THREADS
1836 && requested_child
->status_pending_p
1837 && requested_child
->collecting_fast_tracepoint
)
1839 enqueue_one_deferred_signal (requested_child
,
1840 &requested_child
->status_pending
);
1841 requested_child
->status_pending_p
= 0;
1842 requested_child
->status_pending
= 0;
1843 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
1846 if (requested_child
->suspended
1847 && requested_child
->status_pending_p
)
1848 fatal ("requesting an event out of a suspended child?");
1850 if (requested_child
->status_pending_p
)
1851 event_child
= requested_child
;
1854 if (event_child
!= NULL
)
1857 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1858 lwpid_of (event_child
), event_child
->status_pending
);
1859 *wstat
= event_child
->status_pending
;
1860 event_child
->status_pending_p
= 0;
1861 event_child
->status_pending
= 0;
1862 current_inferior
= get_lwp_thread (event_child
);
1863 return lwpid_of (event_child
);
1866 if (ptid_is_pid (ptid
))
1868 /* A request to wait for a specific tgid. This is not possible
1869 with waitpid, so instead, we wait for any child, and leave
1870 children we're not interested in right now with a pending
1871 status to report later. */
1872 wait_ptid
= minus_one_ptid
;
1877 /* We only enter this loop if no process has a pending wait status. Thus
1878 any action taken in response to a wait status inside this loop is
1879 responding as soon as we detect the status, not after any pending
1883 event_child
= linux_wait_for_lwp (wait_ptid
, wstat
, options
);
1885 if ((options
& WNOHANG
) && event_child
== NULL
)
1888 fprintf (stderr
, "WNOHANG set, no event found\n");
1892 if (event_child
== NULL
)
1893 error ("event from unknown child");
1895 if (ptid_is_pid (ptid
)
1896 && ptid_get_pid (ptid
) != ptid_get_pid (ptid_of (event_child
)))
1898 if (! WIFSTOPPED (*wstat
))
1899 mark_lwp_dead (event_child
, *wstat
);
1902 event_child
->status_pending_p
= 1;
1903 event_child
->status_pending
= *wstat
;
1908 current_inferior
= get_lwp_thread (event_child
);
1910 /* Check for thread exit. */
1911 if (! WIFSTOPPED (*wstat
))
1914 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1916 /* If the last thread is exiting, just return. */
1917 if (last_thread_of_process_p (current_inferior
))
1920 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1921 lwpid_of (event_child
));
1922 return lwpid_of (event_child
);
1927 current_inferior
= (struct thread_info
*) all_threads
.head
;
1929 fprintf (stderr
, "Current inferior is now %ld\n",
1930 lwpid_of (get_thread_lwp (current_inferior
)));
1934 current_inferior
= NULL
;
1936 fprintf (stderr
, "Current inferior is now <NULL>\n");
1939 /* If we were waiting for this particular child to do something...
1940 well, it did something. */
1941 if (requested_child
!= NULL
)
1943 int lwpid
= lwpid_of (event_child
);
1945 /* Cancel the step-over operation --- the thread that
1946 started it is gone. */
1947 if (finish_step_over (event_child
))
1948 unstop_all_lwps (1, event_child
);
1949 delete_lwp (event_child
);
1953 delete_lwp (event_child
);
1955 /* Wait for a more interesting event. */
1959 if (event_child
->must_set_ptrace_flags
)
1961 linux_enable_event_reporting (lwpid_of (event_child
));
1962 event_child
->must_set_ptrace_flags
= 0;
1965 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1966 && *wstat
>> 16 != 0)
1968 handle_extended_wait (event_child
, *wstat
);
1972 if (WIFSTOPPED (*wstat
)
1973 && WSTOPSIG (*wstat
) == SIGSTOP
1974 && event_child
->stop_expected
)
1979 fprintf (stderr
, "Expected stop.\n");
1980 event_child
->stop_expected
= 0;
1982 should_stop
= (current_inferior
->last_resume_kind
== resume_stop
1983 || stopping_threads
!= NOT_STOPPING_THREADS
);
1987 linux_resume_one_lwp (event_child
,
1988 event_child
->stepping
, 0, NULL
);
1993 return lwpid_of (event_child
);
2000 /* Count the LWP's that have had events. */
2003 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2005 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2006 struct thread_info
*thread
= get_lwp_thread (lp
);
2009 gdb_assert (count
!= NULL
);
2011 /* Count only resumed LWPs that have a SIGTRAP event pending that
2012 should be reported to GDB. */
2013 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2014 && thread
->last_resume_kind
!= resume_stop
2015 && lp
->status_pending_p
2016 && WIFSTOPPED (lp
->status_pending
)
2017 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2018 && !breakpoint_inserted_here (lp
->stop_pc
))
2024 /* Select the LWP (if any) that is currently being single-stepped. */
2027 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2029 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2030 struct thread_info
*thread
= get_lwp_thread (lp
);
2032 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2033 && thread
->last_resume_kind
== resume_step
2034 && lp
->status_pending_p
)
2040 /* Select the Nth LWP that has had a SIGTRAP event that should be
2044 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2046 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2047 struct thread_info
*thread
= get_lwp_thread (lp
);
2048 int *selector
= data
;
2050 gdb_assert (selector
!= NULL
);
2052 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2053 if (thread
->last_resume_kind
!= resume_stop
2054 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2055 && lp
->status_pending_p
2056 && WIFSTOPPED (lp
->status_pending
)
2057 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2058 && !breakpoint_inserted_here (lp
->stop_pc
))
2059 if ((*selector
)-- == 0)
2066 cancel_breakpoints_callback (struct inferior_list_entry
*entry
, void *data
)
2068 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2069 struct thread_info
*thread
= get_lwp_thread (lp
);
2070 struct lwp_info
*event_lp
= data
;
2072 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
2076 /* If a LWP other than the LWP that we're reporting an event for has
2077 hit a GDB breakpoint (as opposed to some random trap signal),
2078 then just arrange for it to hit it again later. We don't keep
2079 the SIGTRAP status and don't forward the SIGTRAP signal to the
2080 LWP. We will handle the current event, eventually we will resume
2081 all LWPs, and this one will get its breakpoint trap again.
2083 If we do not do this, then we run the risk that the user will
2084 delete or disable the breakpoint, but the LWP will have already
2087 if (thread
->last_resume_kind
!= resume_stop
2088 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2089 && lp
->status_pending_p
2090 && WIFSTOPPED (lp
->status_pending
)
2091 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2093 && !lp
->stopped_by_watchpoint
2094 && cancel_breakpoint (lp
))
2095 /* Throw away the SIGTRAP. */
2096 lp
->status_pending_p
= 0;
2102 linux_cancel_breakpoints (void)
2104 find_inferior (&all_lwps
, cancel_breakpoints_callback
, NULL
);
2107 /* Select one LWP out of those that have events pending. */
2110 select_event_lwp (struct lwp_info
**orig_lp
)
2113 int random_selector
;
2114 struct lwp_info
*event_lp
;
2116 /* Give preference to any LWP that is being single-stepped. */
2118 = (struct lwp_info
*) find_inferior (&all_lwps
,
2119 select_singlestep_lwp_callback
, NULL
);
2120 if (event_lp
!= NULL
)
2124 "SEL: Select single-step %s\n",
2125 target_pid_to_str (ptid_of (event_lp
)));
2129 /* No single-stepping LWP. Select one at random, out of those
2130 which have had SIGTRAP events. */
2132 /* First see how many SIGTRAP events we have. */
2133 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
2135 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
2136 random_selector
= (int)
2137 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2139 if (debug_threads
&& num_events
> 1)
2141 "SEL: Found %d SIGTRAP events, selecting #%d\n",
2142 num_events
, random_selector
);
2144 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
2145 select_event_lwp_callback
,
2149 if (event_lp
!= NULL
)
2151 /* Switch the event LWP. */
2152 *orig_lp
= event_lp
;
2156 /* Decrement the suspend count of an LWP. */
2159 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2161 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2163 /* Ignore EXCEPT. */
2169 gdb_assert (lwp
->suspended
>= 0);
2173 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2177 unsuspend_all_lwps (struct lwp_info
*except
)
2179 find_inferior (&all_lwps
, unsuspend_one_lwp
, except
);
2182 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2183 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2185 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2186 static ptid_t
linux_wait_1 (ptid_t ptid
,
2187 struct target_waitstatus
*ourstatus
,
2188 int target_options
);
2190 /* Stabilize threads (move out of jump pads).
2192 If a thread is midway collecting a fast tracepoint, we need to
2193 finish the collection and move it out of the jump pad before
2194 reporting the signal.
2196 This avoids recursion while collecting (when a signal arrives
2197 midway, and the signal handler itself collects), which would trash
2198 the trace buffer. In case the user set a breakpoint in a signal
2199 handler, this avoids the backtrace showing the jump pad, etc..
2200 Most importantly, there are certain things we can't do safely if
2201 threads are stopped in a jump pad (or in its callee's). For
2204 - starting a new trace run. A thread still collecting the
2205 previous run, could trash the trace buffer when resumed. The trace
2206 buffer control structures would have been reset but the thread had
2207 no way to tell. The thread could even midway memcpy'ing to the
2208 buffer, which would mean that when resumed, it would clobber the
2209 trace buffer that had been set for a new run.
2211 - we can't rewrite/reuse the jump pads for new tracepoints
2212 safely. Say you do tstart while a thread is stopped midway while
2213 collecting. When the thread is later resumed, it finishes the
2214 collection, and returns to the jump pad, to execute the original
2215 instruction that was under the tracepoint jump at the time the
2216 older run had been started. If the jump pad had been rewritten
2217 since for something else in the new run, the thread would now
2218 execute the wrong / random instructions. */
2221 linux_stabilize_threads (void)
2223 struct thread_info
*save_inferior
;
2224 struct lwp_info
*lwp_stuck
;
2227 = (struct lwp_info
*) find_inferior (&all_lwps
,
2228 stuck_in_jump_pad_callback
, NULL
);
2229 if (lwp_stuck
!= NULL
)
2232 fprintf (stderr
, "can't stabilize, LWP %ld is stuck in jump pad\n",
2233 lwpid_of (lwp_stuck
));
2237 save_inferior
= current_inferior
;
2239 stabilizing_threads
= 1;
2242 for_each_inferior (&all_lwps
, move_out_of_jump_pad_callback
);
2244 /* Loop until all are stopped out of the jump pads. */
2245 while (find_inferior (&all_lwps
, lwp_running
, NULL
) != NULL
)
2247 struct target_waitstatus ourstatus
;
2248 struct lwp_info
*lwp
;
2251 /* Note that we go through the full wait even loop. While
2252 moving threads out of jump pad, we need to be able to step
2253 over internal breakpoints and such. */
2254 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2256 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2258 lwp
= get_thread_lwp (current_inferior
);
2263 if (ourstatus
.value
.sig
!= TARGET_SIGNAL_0
2264 || current_inferior
->last_resume_kind
== resume_stop
)
2266 wstat
= W_STOPCODE (target_signal_to_host (ourstatus
.value
.sig
));
2267 enqueue_one_deferred_signal (lwp
, &wstat
);
2272 find_inferior (&all_lwps
, unsuspend_one_lwp
, NULL
);
2274 stabilizing_threads
= 0;
2276 current_inferior
= save_inferior
;
2281 = (struct lwp_info
*) find_inferior (&all_lwps
,
2282 stuck_in_jump_pad_callback
, NULL
);
2283 if (lwp_stuck
!= NULL
)
2284 fprintf (stderr
, "couldn't stabilize, LWP %ld got stuck in jump pad\n",
2285 lwpid_of (lwp_stuck
));
2289 /* Wait for process, returns status. */
2292 linux_wait_1 (ptid_t ptid
,
2293 struct target_waitstatus
*ourstatus
, int target_options
)
2296 struct lwp_info
*event_child
;
2299 int step_over_finished
;
2300 int bp_explains_trap
;
2301 int maybe_internal_trap
;
2305 /* Translate generic target options into linux options. */
2307 if (target_options
& TARGET_WNOHANG
)
2311 bp_explains_trap
= 0;
2313 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2315 /* If we were only supposed to resume one thread, only wait for
2316 that thread - if it's still alive. If it died, however - which
2317 can happen if we're coming from the thread death case below -
2318 then we need to make sure we restart the other threads. We could
2319 pick a thread at random or restart all; restarting all is less
2322 && !ptid_equal (cont_thread
, null_ptid
)
2323 && !ptid_equal (cont_thread
, minus_one_ptid
))
2325 struct thread_info
*thread
;
2327 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
2330 /* No stepping, no signal - unless one is pending already, of course. */
2333 struct thread_resume resume_info
;
2334 resume_info
.thread
= minus_one_ptid
;
2335 resume_info
.kind
= resume_continue
;
2336 resume_info
.sig
= 0;
2337 linux_resume (&resume_info
, 1);
2343 if (ptid_equal (step_over_bkpt
, null_ptid
))
2344 pid
= linux_wait_for_event (ptid
, &w
, options
);
2348 fprintf (stderr
, "step_over_bkpt set [%s], doing a blocking wait\n",
2349 target_pid_to_str (step_over_bkpt
));
2350 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2353 if (pid
== 0) /* only if TARGET_WNOHANG */
2356 event_child
= get_thread_lwp (current_inferior
);
2358 /* If we are waiting for a particular child, and it exited,
2359 linux_wait_for_event will return its exit status. Similarly if
2360 the last child exited. If this is not the last child, however,
2361 do not report it as exited until there is a 'thread exited' response
2362 available in the remote protocol. Instead, just wait for another event.
2363 This should be safe, because if the thread crashed we will already
2364 have reported the termination signal to GDB; that should stop any
2365 in-progress stepping operations, etc.
2367 Report the exit status of the last thread to exit. This matches
2368 LinuxThreads' behavior. */
2370 if (last_thread_of_process_p (current_inferior
))
2372 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2376 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2377 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2381 "\nChild exited with retcode = %x \n",
2386 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2387 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
2391 "\nChild terminated with signal = %x \n",
2396 return ptid_of (event_child
);
2401 if (!WIFSTOPPED (w
))
2405 /* If this event was not handled before, and is not a SIGTRAP, we
2406 report it. SIGILL and SIGSEGV are also treated as traps in case
2407 a breakpoint is inserted at the current PC. If this target does
2408 not support internal breakpoints at all, we also report the
2409 SIGTRAP without further processing; it's of no concern to us. */
2411 = (supports_breakpoints ()
2412 && (WSTOPSIG (w
) == SIGTRAP
2413 || ((WSTOPSIG (w
) == SIGILL
2414 || WSTOPSIG (w
) == SIGSEGV
)
2415 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2417 if (maybe_internal_trap
)
2419 /* Handle anything that requires bookkeeping before deciding to
2420 report the event or continue waiting. */
2422 /* First check if we can explain the SIGTRAP with an internal
2423 breakpoint, or if we should possibly report the event to GDB.
2424 Do this before anything that may remove or insert a
2426 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2428 /* We have a SIGTRAP, possibly a step-over dance has just
2429 finished. If so, tweak the state machine accordingly,
2430 reinsert breakpoints and delete any reinsert (software
2431 single-step) breakpoints. */
2432 step_over_finished
= finish_step_over (event_child
);
2434 /* Now invoke the callbacks of any internal breakpoints there. */
2435 check_breakpoints (event_child
->stop_pc
);
2437 /* Handle tracepoint data collecting. This may overflow the
2438 trace buffer, and cause a tracing stop, removing
2440 trace_event
= handle_tracepoints (event_child
);
2442 if (bp_explains_trap
)
2444 /* If we stepped or ran into an internal breakpoint, we've
2445 already handled it. So next time we resume (from this
2446 PC), we should step over it. */
2448 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2450 if (breakpoint_here (event_child
->stop_pc
))
2451 event_child
->need_step_over
= 1;
2456 /* We have some other signal, possibly a step-over dance was in
2457 progress, and it should be cancelled too. */
2458 step_over_finished
= finish_step_over (event_child
);
2461 /* We have all the data we need. Either report the event to GDB, or
2462 resume threads and keep waiting for more. */
2464 /* If we're collecting a fast tracepoint, finish the collection and
2465 move out of the jump pad before delivering a signal. See
2466 linux_stabilize_threads. */
2469 && WSTOPSIG (w
) != SIGTRAP
2470 && supports_fast_tracepoints ()
2471 && agent_loaded_p ())
2475 "Got signal %d for LWP %ld. Check if we need "
2476 "to defer or adjust it.\n",
2477 WSTOPSIG (w
), lwpid_of (event_child
));
2479 /* Allow debugging the jump pad itself. */
2480 if (current_inferior
->last_resume_kind
!= resume_step
2481 && maybe_move_out_of_jump_pad (event_child
, &w
))
2483 enqueue_one_deferred_signal (event_child
, &w
);
2487 "Signal %d for LWP %ld deferred (in jump pad)\n",
2488 WSTOPSIG (w
), lwpid_of (event_child
));
2490 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2495 if (event_child
->collecting_fast_tracepoint
)
2499 LWP %ld was trying to move out of the jump pad (%d). \
2500 Check if we're already there.\n",
2501 lwpid_of (event_child
),
2502 event_child
->collecting_fast_tracepoint
);
2506 event_child
->collecting_fast_tracepoint
2507 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2509 if (event_child
->collecting_fast_tracepoint
!= 1)
2511 /* No longer need this breakpoint. */
2512 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2516 "No longer need exit-jump-pad bkpt; removing it."
2517 "stopping all threads momentarily.\n");
2519 /* Other running threads could hit this breakpoint.
2520 We don't handle moribund locations like GDB does,
2521 instead we always pause all threads when removing
2522 breakpoints, so that any step-over or
2523 decr_pc_after_break adjustment is always taken
2524 care of while the breakpoint is still
2526 stop_all_lwps (1, event_child
);
2527 cancel_breakpoints ();
2529 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2530 event_child
->exit_jump_pad_bkpt
= NULL
;
2532 unstop_all_lwps (1, event_child
);
2534 gdb_assert (event_child
->suspended
>= 0);
2538 if (event_child
->collecting_fast_tracepoint
== 0)
2542 "fast tracepoint finished "
2543 "collecting successfully.\n");
2545 /* We may have a deferred signal to report. */
2546 if (dequeue_one_deferred_signal (event_child
, &w
))
2549 fprintf (stderr
, "dequeued one signal.\n");
2554 fprintf (stderr
, "no deferred signals.\n");
2556 if (stabilizing_threads
)
2558 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2559 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2560 return ptid_of (event_child
);
2566 /* Check whether GDB would be interested in this event. */
2568 /* If GDB is not interested in this signal, don't stop other
2569 threads, and don't report it to GDB. Just resume the inferior
2570 right away. We do this for threading-related signals as well as
2571 any that GDB specifically requested we ignore. But never ignore
2572 SIGSTOP if we sent it ourselves, and do not ignore signals when
2573 stepping - they may require special handling to skip the signal
2575 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2578 && current_inferior
->last_resume_kind
!= resume_step
2580 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2581 (current_process ()->private->thread_db
!= NULL
2582 && (WSTOPSIG (w
) == __SIGRTMIN
2583 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2586 (pass_signals
[target_signal_from_host (WSTOPSIG (w
))]
2587 && !(WSTOPSIG (w
) == SIGSTOP
2588 && current_inferior
->last_resume_kind
== resume_stop
))))
2590 siginfo_t info
, *info_p
;
2593 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
2594 WSTOPSIG (w
), lwpid_of (event_child
));
2596 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
2600 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2601 WSTOPSIG (w
), info_p
);
2605 /* If GDB wanted this thread to single step, we always want to
2606 report the SIGTRAP, and let GDB handle it. Watchpoints should
2607 always be reported. So should signals we can't explain. A
2608 SIGTRAP we can't explain could be a GDB breakpoint --- we may or
2609 not support Z0 breakpoints. If we do, we're be able to handle
2610 GDB breakpoints on top of internal breakpoints, by handling the
2611 internal breakpoint and still reporting the event to GDB. If we
2612 don't, we're out of luck, GDB won't see the breakpoint hit. */
2613 report_to_gdb
= (!maybe_internal_trap
2614 || current_inferior
->last_resume_kind
== resume_step
2615 || event_child
->stopped_by_watchpoint
2616 || (!step_over_finished
2617 && !bp_explains_trap
&& !trace_event
)
2618 || (gdb_breakpoint_here (event_child
->stop_pc
)
2619 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)));
2621 /* We found no reason GDB would want us to stop. We either hit one
2622 of our own breakpoints, or finished an internal step GDB
2623 shouldn't know about. */
2628 if (bp_explains_trap
)
2629 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2630 if (step_over_finished
)
2631 fprintf (stderr
, "Step-over finished.\n");
2633 fprintf (stderr
, "Tracepoint event.\n");
2636 /* We're not reporting this breakpoint to GDB, so apply the
2637 decr_pc_after_break adjustment to the inferior's regcache
2640 if (the_low_target
.set_pc
!= NULL
)
2642 struct regcache
*regcache
2643 = get_thread_regcache (get_lwp_thread (event_child
), 1);
2644 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2647 /* We may have finished stepping over a breakpoint. If so,
2648 we've stopped and suspended all LWPs momentarily except the
2649 stepping one. This is where we resume them all again. We're
2650 going to keep waiting, so use proceed, which handles stepping
2651 over the next breakpoint. */
2653 fprintf (stderr
, "proceeding all threads.\n");
2655 if (step_over_finished
)
2656 unsuspend_all_lwps (event_child
);
2658 proceed_all_lwps ();
2664 if (current_inferior
->last_resume_kind
== resume_step
)
2665 fprintf (stderr
, "GDB wanted to single-step, reporting event.\n");
2666 if (event_child
->stopped_by_watchpoint
)
2667 fprintf (stderr
, "Stopped by watchpoint.\n");
2668 if (gdb_breakpoint_here (event_child
->stop_pc
))
2669 fprintf (stderr
, "Stopped by GDB breakpoint.\n");
2671 fprintf (stderr
, "Hit a non-gdbserver trap event.\n");
2674 /* Alright, we're going to report a stop. */
2676 if (!non_stop
&& !stabilizing_threads
)
2678 /* In all-stop, stop all threads. */
2679 stop_all_lwps (0, NULL
);
2681 /* If we're not waiting for a specific LWP, choose an event LWP
2682 from among those that have had events. Giving equal priority
2683 to all LWPs that have had events helps prevent
2685 if (ptid_equal (ptid
, minus_one_ptid
))
2687 event_child
->status_pending_p
= 1;
2688 event_child
->status_pending
= w
;
2690 select_event_lwp (&event_child
);
2692 event_child
->status_pending_p
= 0;
2693 w
= event_child
->status_pending
;
2696 /* Now that we've selected our final event LWP, cancel any
2697 breakpoints in other LWPs that have hit a GDB breakpoint.
2698 See the comment in cancel_breakpoints_callback to find out
2700 find_inferior (&all_lwps
, cancel_breakpoints_callback
, event_child
);
2702 /* If we were going a step-over, all other threads but the stepping one
2703 had been paused in start_step_over, with their suspend counts
2704 incremented. We don't want to do a full unstop/unpause, because we're
2705 in all-stop mode (so we want threads stopped), but we still need to
2706 unsuspend the other threads, to decrement their `suspended' count
2708 if (step_over_finished
)
2709 unsuspend_all_lwps (event_child
);
2711 /* Stabilize threads (move out of jump pads). */
2712 stabilize_threads ();
2716 /* If we just finished a step-over, then all threads had been
2717 momentarily paused. In all-stop, that's fine, we want
2718 threads stopped by now anyway. In non-stop, we need to
2719 re-resume threads that GDB wanted to be running. */
2720 if (step_over_finished
)
2721 unstop_all_lwps (1, event_child
);
2724 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2726 if (current_inferior
->last_resume_kind
== resume_stop
2727 && WSTOPSIG (w
) == SIGSTOP
)
2729 /* A thread that has been requested to stop by GDB with vCont;t,
2730 and it stopped cleanly, so report as SIG0. The use of
2731 SIGSTOP is an implementation detail. */
2732 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2734 else if (current_inferior
->last_resume_kind
== resume_stop
2735 && WSTOPSIG (w
) != SIGSTOP
)
2737 /* A thread that has been requested to stop by GDB with vCont;t,
2738 but, it stopped for other reasons. */
2739 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2743 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2746 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
2749 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
2750 target_pid_to_str (ptid_of (event_child
)),
2752 ourstatus
->value
.sig
);
2754 return ptid_of (event_child
);
2757 /* Get rid of any pending event in the pipe. */
2759 async_file_flush (void)
2765 ret
= read (linux_event_pipe
[0], &buf
, 1);
2766 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
2769 /* Put something in the pipe, so the event loop wakes up. */
2771 async_file_mark (void)
2775 async_file_flush ();
2778 ret
= write (linux_event_pipe
[1], "+", 1);
2779 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
2781 /* Ignore EAGAIN. If the pipe is full, the event loop will already
2782 be awakened anyway. */
2786 linux_wait (ptid_t ptid
,
2787 struct target_waitstatus
*ourstatus
, int target_options
)
2792 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
2794 /* Flush the async file first. */
2795 if (target_is_async_p ())
2796 async_file_flush ();
2798 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
2800 /* If at least one stop was reported, there may be more. A single
2801 SIGCHLD can signal more than one child stop. */
2802 if (target_is_async_p ()
2803 && (target_options
& TARGET_WNOHANG
) != 0
2804 && !ptid_equal (event_ptid
, null_ptid
))
2810 /* Send a signal to an LWP. */
2813 kill_lwp (unsigned long lwpid
, int signo
)
2815 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2816 fails, then we are not using nptl threads and we should be using kill. */
2820 static int tkill_failed
;
2827 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2828 if (errno
!= ENOSYS
)
2835 return kill (lwpid
, signo
);
2839 linux_stop_lwp (struct lwp_info
*lwp
)
2845 send_sigstop (struct lwp_info
*lwp
)
2849 pid
= lwpid_of (lwp
);
2851 /* If we already have a pending stop signal for this process, don't
2853 if (lwp
->stop_expected
)
2856 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
2862 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
2864 lwp
->stop_expected
= 1;
2865 kill_lwp (pid
, SIGSTOP
);
2869 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
2871 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2873 /* Ignore EXCEPT. */
2884 /* Increment the suspend count of an LWP, and stop it, if not stopped
2887 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
2890 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2892 /* Ignore EXCEPT. */
2898 return send_sigstop_callback (entry
, except
);
2902 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
2904 /* It's dead, really. */
2907 /* Store the exit status for later. */
2908 lwp
->status_pending_p
= 1;
2909 lwp
->status_pending
= wstat
;
2911 /* Prevent trying to stop it. */
2914 /* No further stops are expected from a dead lwp. */
2915 lwp
->stop_expected
= 0;
2919 wait_for_sigstop (struct inferior_list_entry
*entry
)
2921 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2922 struct thread_info
*saved_inferior
;
2931 fprintf (stderr
, "wait_for_sigstop: LWP %ld already stopped\n",
2936 saved_inferior
= current_inferior
;
2937 if (saved_inferior
!= NULL
)
2938 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
2940 saved_tid
= null_ptid
; /* avoid bogus unused warning */
2942 ptid
= lwp
->head
.id
;
2945 fprintf (stderr
, "wait_for_sigstop: pulling one event\n");
2947 pid
= linux_wait_for_event (ptid
, &wstat
, __WALL
);
2949 /* If we stopped with a non-SIGSTOP signal, save it for later
2950 and record the pending SIGSTOP. If the process exited, just
2952 if (WIFSTOPPED (wstat
))
2955 fprintf (stderr
, "LWP %ld stopped with signal %d\n",
2956 lwpid_of (lwp
), WSTOPSIG (wstat
));
2958 if (WSTOPSIG (wstat
) != SIGSTOP
)
2961 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
2962 lwpid_of (lwp
), wstat
);
2964 lwp
->status_pending_p
= 1;
2965 lwp
->status_pending
= wstat
;
2971 fprintf (stderr
, "Process %d exited while stopping LWPs\n", pid
);
2973 lwp
= find_lwp_pid (pid_to_ptid (pid
));
2976 /* Leave this status pending for the next time we're able to
2977 report it. In the mean time, we'll report this lwp as
2978 dead to GDB, so GDB doesn't try to read registers and
2979 memory from it. This can only happen if this was the
2980 last thread of the process; otherwise, PID is removed
2981 from the thread tables before linux_wait_for_event
2983 mark_lwp_dead (lwp
, wstat
);
2987 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
2988 current_inferior
= saved_inferior
;
2992 fprintf (stderr
, "Previously current thread died.\n");
2996 /* We can't change the current inferior behind GDB's back,
2997 otherwise, a subsequent command may apply to the wrong
2999 current_inferior
= NULL
;
3003 /* Set a valid thread as current. */
3004 set_desired_inferior (0);
3009 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3010 move it out, because we need to report the stop event to GDB. For
3011 example, if the user puts a breakpoint in the jump pad, it's
3012 because she wants to debug it. */
3015 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3017 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3018 struct thread_info
*thread
= get_lwp_thread (lwp
);
3020 gdb_assert (lwp
->suspended
== 0);
3021 gdb_assert (lwp
->stopped
);
3023 /* Allow debugging the jump pad, gdb_collect, etc.. */
3024 return (supports_fast_tracepoints ()
3025 && agent_loaded_p ()
3026 && (gdb_breakpoint_here (lwp
->stop_pc
)
3027 || lwp
->stopped_by_watchpoint
3028 || thread
->last_resume_kind
== resume_step
)
3029 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3033 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3035 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3036 struct thread_info
*thread
= get_lwp_thread (lwp
);
3039 gdb_assert (lwp
->suspended
== 0);
3040 gdb_assert (lwp
->stopped
);
3042 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3044 /* Allow debugging the jump pad, gdb_collect, etc. */
3045 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3046 && !lwp
->stopped_by_watchpoint
3047 && thread
->last_resume_kind
!= resume_step
3048 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3052 "LWP %ld needs stabilizing (in jump pad)\n",
3057 lwp
->status_pending_p
= 0;
3058 enqueue_one_deferred_signal (lwp
, wstat
);
3062 "Signal %d for LWP %ld deferred "
3064 WSTOPSIG (*wstat
), lwpid_of (lwp
));
3067 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3074 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3076 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3085 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3086 If SUSPEND, then also increase the suspend count of every LWP,
3090 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3092 /* Should not be called recursively. */
3093 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3095 stopping_threads
= (suspend
3096 ? STOPPING_AND_SUSPENDING_THREADS
3097 : STOPPING_THREADS
);
3100 find_inferior (&all_lwps
, suspend_and_send_sigstop_callback
, except
);
3102 find_inferior (&all_lwps
, send_sigstop_callback
, except
);
3103 for_each_inferior (&all_lwps
, wait_for_sigstop
);
3104 stopping_threads
= NOT_STOPPING_THREADS
;
3107 /* Resume execution of the inferior process.
3108 If STEP is nonzero, single-step it.
3109 If SIGNAL is nonzero, give it that signal. */
3112 linux_resume_one_lwp (struct lwp_info
*lwp
,
3113 int step
, int signal
, siginfo_t
*info
)
3115 struct thread_info
*saved_inferior
;
3116 int fast_tp_collecting
;
3118 if (lwp
->stopped
== 0)
3121 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3123 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3125 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3126 user used the "jump" command, or "set $pc = foo"). */
3127 if (lwp
->stop_pc
!= get_pc (lwp
))
3129 /* Collecting 'while-stepping' actions doesn't make sense
3131 release_while_stepping_state_list (get_lwp_thread (lwp
));
3134 /* If we have pending signals or status, and a new signal, enqueue the
3135 signal. Also enqueue the signal if we are waiting to reinsert a
3136 breakpoint; it will be picked up again below. */
3138 && (lwp
->status_pending_p
3139 || lwp
->pending_signals
!= NULL
3140 || lwp
->bp_reinsert
!= 0
3141 || fast_tp_collecting
))
3143 struct pending_signals
*p_sig
;
3144 p_sig
= xmalloc (sizeof (*p_sig
));
3145 p_sig
->prev
= lwp
->pending_signals
;
3146 p_sig
->signal
= signal
;
3148 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3150 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3151 lwp
->pending_signals
= p_sig
;
3154 if (lwp
->status_pending_p
)
3157 fprintf (stderr
, "Not resuming lwp %ld (%s, signal %d, stop %s);"
3158 " has pending status\n",
3159 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3160 lwp
->stop_expected
? "expected" : "not expected");
3164 saved_inferior
= current_inferior
;
3165 current_inferior
= get_lwp_thread (lwp
);
3168 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
3169 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3170 lwp
->stop_expected
? "expected" : "not expected");
3172 /* This bit needs some thinking about. If we get a signal that
3173 we must report while a single-step reinsert is still pending,
3174 we often end up resuming the thread. It might be better to
3175 (ew) allow a stack of pending events; then we could be sure that
3176 the reinsert happened right away and not lose any signals.
3178 Making this stack would also shrink the window in which breakpoints are
3179 uninserted (see comment in linux_wait_for_lwp) but not enough for
3180 complete correctness, so it won't solve that problem. It may be
3181 worthwhile just to solve this one, however. */
3182 if (lwp
->bp_reinsert
!= 0)
3185 fprintf (stderr
, " pending reinsert at 0x%s\n",
3186 paddress (lwp
->bp_reinsert
));
3188 if (lwp
->bp_reinsert
!= 0 && can_hardware_single_step ())
3190 if (fast_tp_collecting
== 0)
3193 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
3195 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
3202 /* Postpone any pending signal. It was enqueued above. */
3206 if (fast_tp_collecting
== 1)
3210 lwp %ld wants to get out of fast tracepoint jump pad (exit-jump-pad-bkpt)\n",
3213 /* Postpone any pending signal. It was enqueued above. */
3216 else if (fast_tp_collecting
== 2)
3220 lwp %ld wants to get out of fast tracepoint jump pad single-stepping\n",
3223 if (can_hardware_single_step ())
3226 fatal ("moving out of jump pad single-stepping"
3227 " not implemented on this target");
3229 /* Postpone any pending signal. It was enqueued above. */
3233 /* If we have while-stepping actions in this thread set it stepping.
3234 If we have a signal to deliver, it may or may not be set to
3235 SIG_IGN, we don't know. Assume so, and allow collecting
3236 while-stepping into a signal handler. A possible smart thing to
3237 do would be to set an internal breakpoint at the signal return
3238 address, continue, and carry on catching this while-stepping
3239 action only when that breakpoint is hit. A future
3241 if (get_lwp_thread (lwp
)->while_stepping
!= NULL
3242 && can_hardware_single_step ())
3246 "lwp %ld has a while-stepping action -> forcing step.\n",
3251 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
3253 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
3254 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
3255 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
3258 /* If we have pending signals, consume one unless we are trying to
3259 reinsert a breakpoint or we're trying to finish a fast tracepoint
3261 if (lwp
->pending_signals
!= NULL
3262 && lwp
->bp_reinsert
== 0
3263 && fast_tp_collecting
== 0)
3265 struct pending_signals
**p_sig
;
3267 p_sig
= &lwp
->pending_signals
;
3268 while ((*p_sig
)->prev
!= NULL
)
3269 p_sig
= &(*p_sig
)->prev
;
3271 signal
= (*p_sig
)->signal
;
3272 if ((*p_sig
)->info
.si_signo
!= 0)
3273 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
3279 if (the_low_target
.prepare_to_resume
!= NULL
)
3280 the_low_target
.prepare_to_resume (lwp
);
3282 regcache_invalidate_one ((struct inferior_list_entry
*)
3283 get_lwp_thread (lwp
));
3286 lwp
->stopped_by_watchpoint
= 0;
3287 lwp
->stepping
= step
;
3288 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0,
3289 /* Coerce to a uintptr_t first to avoid potential gcc warning
3290 of coercing an 8 byte integer to a 4 byte pointer. */
3291 (PTRACE_ARG4_TYPE
) (uintptr_t) signal
);
3293 current_inferior
= saved_inferior
;
3296 /* ESRCH from ptrace either means that the thread was already
3297 running (an error) or that it is gone (a race condition). If
3298 it's gone, we will get a notification the next time we wait,
3299 so we can ignore the error. We could differentiate these
3300 two, but it's tricky without waiting; the thread still exists
3301 as a zombie, so sending it signal 0 would succeed. So just
3306 perror_with_name ("ptrace");
3310 struct thread_resume_array
3312 struct thread_resume
*resume
;
3316 /* This function is called once per thread. We look up the thread
3317 in RESUME_PTR, and mark the thread with a pointer to the appropriate
3320 This algorithm is O(threads * resume elements), but resume elements
3321 is small (and will remain small at least until GDB supports thread
3324 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3326 struct lwp_info
*lwp
;
3327 struct thread_info
*thread
;
3329 struct thread_resume_array
*r
;
3331 thread
= (struct thread_info
*) entry
;
3332 lwp
= get_thread_lwp (thread
);
3335 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3337 ptid_t ptid
= r
->resume
[ndx
].thread
;
3338 if (ptid_equal (ptid
, minus_one_ptid
)
3339 || ptid_equal (ptid
, entry
->id
)
3340 || (ptid_is_pid (ptid
)
3341 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
3342 || (ptid_get_lwp (ptid
) == -1
3343 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
3345 if (r
->resume
[ndx
].kind
== resume_stop
3346 && thread
->last_resume_kind
== resume_stop
)
3349 fprintf (stderr
, "already %s LWP %ld at GDB's request\n",
3350 thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
3358 lwp
->resume
= &r
->resume
[ndx
];
3359 thread
->last_resume_kind
= lwp
->resume
->kind
;
3361 /* If we had a deferred signal to report, dequeue one now.
3362 This can happen if LWP gets more than one signal while
3363 trying to get out of a jump pad. */
3365 && !lwp
->status_pending_p
3366 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3368 lwp
->status_pending_p
= 1;
3372 "Dequeueing deferred signal %d for LWP %ld, "
3373 "leaving status pending.\n",
3374 WSTOPSIG (lwp
->status_pending
), lwpid_of (lwp
));
3381 /* No resume action for this thread. */
3388 /* Set *FLAG_P if this lwp has an interesting status pending. */
3390 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3392 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3394 /* LWPs which will not be resumed are not interesting, because
3395 we might not wait for them next time through linux_wait. */
3396 if (lwp
->resume
== NULL
)
3399 if (lwp
->status_pending_p
)
3400 * (int *) flag_p
= 1;
3405 /* Return 1 if this lwp that GDB wants running is stopped at an
3406 internal breakpoint that we need to step over. It assumes that any
3407 required STOP_PC adjustment has already been propagated to the
3408 inferior's regcache. */
3411 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3413 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3414 struct thread_info
*thread
;
3415 struct thread_info
*saved_inferior
;
3418 /* LWPs which will not be resumed are not interesting, because we
3419 might not wait for them next time through linux_wait. */
3425 "Need step over [LWP %ld]? Ignoring, not stopped\n",
3430 thread
= get_lwp_thread (lwp
);
3432 if (thread
->last_resume_kind
== resume_stop
)
3436 "Need step over [LWP %ld]? Ignoring, should remain stopped\n",
3441 gdb_assert (lwp
->suspended
>= 0);
3447 "Need step over [LWP %ld]? Ignoring, suspended\n",
3452 if (!lwp
->need_step_over
)
3456 "Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
3459 if (lwp
->status_pending_p
)
3463 "Need step over [LWP %ld]? Ignoring, has pending status.\n",
3468 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3472 /* If the PC has changed since we stopped, then don't do anything,
3473 and let the breakpoint/tracepoint be hit. This happens if, for
3474 instance, GDB handled the decr_pc_after_break subtraction itself,
3475 GDB is OOL stepping this thread, or the user has issued a "jump"
3476 command, or poked thread's registers herself. */
3477 if (pc
!= lwp
->stop_pc
)
3481 "Need step over [LWP %ld]? Cancelling, PC was changed. "
3482 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3483 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
3485 lwp
->need_step_over
= 0;
3489 saved_inferior
= current_inferior
;
3490 current_inferior
= thread
;
3492 /* We can only step over breakpoints we know about. */
3493 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3495 /* Don't step over a breakpoint that GDB expects to hit
3496 though. If the condition is being evaluated on the target's side
3497 and it evaluate to false, step over this breakpoint as well. */
3498 if (gdb_breakpoint_here (pc
)
3499 && gdb_condition_true_at_breakpoint (pc
))
3503 "Need step over [LWP %ld]? yes, but found"
3504 " GDB breakpoint at 0x%s; skipping step over\n",
3505 lwpid_of (lwp
), paddress (pc
));
3507 current_inferior
= saved_inferior
;
3514 "Need step over [LWP %ld]? yes, "
3515 "found breakpoint at 0x%s\n",
3516 lwpid_of (lwp
), paddress (pc
));
3518 /* We've found an lwp that needs stepping over --- return 1 so
3519 that find_inferior stops looking. */
3520 current_inferior
= saved_inferior
;
3522 /* If the step over is cancelled, this is set again. */
3523 lwp
->need_step_over
= 0;
3528 current_inferior
= saved_inferior
;
3532 "Need step over [LWP %ld]? No, no breakpoint found at 0x%s\n",
3533 lwpid_of (lwp
), paddress (pc
));
3538 /* Start a step-over operation on LWP. When LWP stopped at a
3539 breakpoint, to make progress, we need to remove the breakpoint out
3540 of the way. If we let other threads run while we do that, they may
3541 pass by the breakpoint location and miss hitting it. To avoid
3542 that, a step-over momentarily stops all threads while LWP is
3543 single-stepped while the breakpoint is temporarily uninserted from
3544 the inferior. When the single-step finishes, we reinsert the
3545 breakpoint, and let all threads that are supposed to be running,
3548 On targets that don't support hardware single-step, we don't
3549 currently support full software single-stepping. Instead, we only
3550 support stepping over the thread event breakpoint, by asking the
3551 low target where to place a reinsert breakpoint. Since this
3552 routine assumes the breakpoint being stepped over is a thread event
3553 breakpoint, it usually assumes the return address of the current
3554 function is a good enough place to set the reinsert breakpoint. */
3557 start_step_over (struct lwp_info
*lwp
)
3559 struct thread_info
*saved_inferior
;
3565 "Starting step-over on LWP %ld. Stopping all threads\n",
3568 stop_all_lwps (1, lwp
);
3569 gdb_assert (lwp
->suspended
== 0);
3572 fprintf (stderr
, "Done stopping all threads for step-over.\n");
3574 /* Note, we should always reach here with an already adjusted PC,
3575 either by GDB (if we're resuming due to GDB's request), or by our
3576 caller, if we just finished handling an internal breakpoint GDB
3577 shouldn't care about. */
3580 saved_inferior
= current_inferior
;
3581 current_inferior
= get_lwp_thread (lwp
);
3583 lwp
->bp_reinsert
= pc
;
3584 uninsert_breakpoints_at (pc
);
3585 uninsert_fast_tracepoint_jumps_at (pc
);
3587 if (can_hardware_single_step ())
3593 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3594 set_reinsert_breakpoint (raddr
);
3598 current_inferior
= saved_inferior
;
3600 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3602 /* Require next event from this LWP. */
3603 step_over_bkpt
= lwp
->head
.id
;
3607 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3608 start_step_over, if still there, and delete any reinsert
3609 breakpoints we've set, on non hardware single-step targets. */
3612 finish_step_over (struct lwp_info
*lwp
)
3614 if (lwp
->bp_reinsert
!= 0)
3617 fprintf (stderr
, "Finished step over.\n");
3619 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3620 may be no breakpoint to reinsert there by now. */
3621 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3622 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3624 lwp
->bp_reinsert
= 0;
3626 /* Delete any software-single-step reinsert breakpoints. No
3627 longer needed. We don't have to worry about other threads
3628 hitting this trap, and later not being able to explain it,
3629 because we were stepping over a breakpoint, and we hold all
3630 threads but LWP stopped while doing that. */
3631 if (!can_hardware_single_step ())
3632 delete_reinsert_breakpoints ();
3634 step_over_bkpt
= null_ptid
;
3641 /* This function is called once per thread. We check the thread's resume
3642 request, which will tell us whether to resume, step, or leave the thread
3643 stopped; and what signal, if any, it should be sent.
3645 For threads which we aren't explicitly told otherwise, we preserve
3646 the stepping flag; this is used for stepping over gdbserver-placed
3649 If pending_flags was set in any thread, we queue any needed
3650 signals, since we won't actually resume. We already have a pending
3651 event to report, so we don't need to preserve any step requests;
3652 they should be re-issued if necessary. */
3655 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3657 struct lwp_info
*lwp
;
3658 struct thread_info
*thread
;
3660 int leave_all_stopped
= * (int *) arg
;
3663 thread
= (struct thread_info
*) entry
;
3664 lwp
= get_thread_lwp (thread
);
3666 if (lwp
->resume
== NULL
)
3669 if (lwp
->resume
->kind
== resume_stop
)
3672 fprintf (stderr
, "resume_stop request for LWP %ld\n", lwpid_of (lwp
));
3677 fprintf (stderr
, "stopping LWP %ld\n", lwpid_of (lwp
));
3679 /* Stop the thread, and wait for the event asynchronously,
3680 through the event loop. */
3686 fprintf (stderr
, "already stopped LWP %ld\n",
3689 /* The LWP may have been stopped in an internal event that
3690 was not meant to be notified back to GDB (e.g., gdbserver
3691 breakpoint), so we should be reporting a stop event in
3694 /* If the thread already has a pending SIGSTOP, this is a
3695 no-op. Otherwise, something later will presumably resume
3696 the thread and this will cause it to cancel any pending
3697 operation, due to last_resume_kind == resume_stop. If
3698 the thread already has a pending status to report, we
3699 will still report it the next time we wait - see
3700 status_pending_p_callback. */
3702 /* If we already have a pending signal to report, then
3703 there's no need to queue a SIGSTOP, as this means we're
3704 midway through moving the LWP out of the jumppad, and we
3705 will report the pending signal as soon as that is
3707 if (lwp
->pending_signals_to_report
== NULL
)
3711 /* For stop requests, we're done. */
3713 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3717 /* If this thread which is about to be resumed has a pending status,
3718 then don't resume any threads - we can just report the pending
3719 status. Make sure to queue any signals that would otherwise be
3720 sent. In all-stop mode, we do this decision based on if *any*
3721 thread has a pending status. If there's a thread that needs the
3722 step-over-breakpoint dance, then don't resume any other thread
3723 but that particular one. */
3724 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
3729 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
3731 step
= (lwp
->resume
->kind
== resume_step
);
3732 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
3737 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
3739 /* If we have a new signal, enqueue the signal. */
3740 if (lwp
->resume
->sig
!= 0)
3742 struct pending_signals
*p_sig
;
3743 p_sig
= xmalloc (sizeof (*p_sig
));
3744 p_sig
->prev
= lwp
->pending_signals
;
3745 p_sig
->signal
= lwp
->resume
->sig
;
3746 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3748 /* If this is the same signal we were previously stopped by,
3749 make sure to queue its siginfo. We can ignore the return
3750 value of ptrace; if it fails, we'll skip
3751 PTRACE_SETSIGINFO. */
3752 if (WIFSTOPPED (lwp
->last_status
)
3753 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
3754 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
3756 lwp
->pending_signals
= p_sig
;
3760 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3766 linux_resume (struct thread_resume
*resume_info
, size_t n
)
3768 struct thread_resume_array array
= { resume_info
, n
};
3769 struct lwp_info
*need_step_over
= NULL
;
3771 int leave_all_stopped
;
3773 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
3775 /* If there is a thread which would otherwise be resumed, which has
3776 a pending status, then don't resume any threads - we can just
3777 report the pending status. Make sure to queue any signals that
3778 would otherwise be sent. In non-stop mode, we'll apply this
3779 logic to each thread individually. We consume all pending events
3780 before considering to start a step-over (in all-stop). */
3783 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
3785 /* If there is a thread which would otherwise be resumed, which is
3786 stopped at a breakpoint that needs stepping over, then don't
3787 resume any threads - have it step over the breakpoint with all
3788 other threads stopped, then resume all threads again. Make sure
3789 to queue any signals that would otherwise be delivered or
3791 if (!any_pending
&& supports_breakpoints ())
3793 = (struct lwp_info
*) find_inferior (&all_lwps
,
3794 need_step_over_p
, NULL
);
3796 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
3800 if (need_step_over
!= NULL
)
3801 fprintf (stderr
, "Not resuming all, need step over\n");
3802 else if (any_pending
)
3804 "Not resuming, all-stop and found "
3805 "an LWP with pending status\n");
3807 fprintf (stderr
, "Resuming, no pending status or step over needed\n");
3810 /* Even if we're leaving threads stopped, queue all signals we'd
3811 otherwise deliver. */
3812 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
3815 start_step_over (need_step_over
);
3818 /* This function is called once per thread. We check the thread's
3819 last resume request, which will tell us whether to resume, step, or
3820 leave the thread stopped. Any signal the client requested to be
3821 delivered has already been enqueued at this point.
3823 If any thread that GDB wants running is stopped at an internal
3824 breakpoint that needs stepping over, we start a step-over operation
3825 on that particular thread, and leave all others stopped. */
3828 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3830 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3831 struct thread_info
*thread
;
3839 "proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
3844 fprintf (stderr
, " LWP %ld already running\n", lwpid_of (lwp
));
3848 thread
= get_lwp_thread (lwp
);
3850 if (thread
->last_resume_kind
== resume_stop
3851 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
3854 fprintf (stderr
, " client wants LWP to remain %ld stopped\n",
3859 if (lwp
->status_pending_p
)
3862 fprintf (stderr
, " LWP %ld has pending status, leaving stopped\n",
3867 gdb_assert (lwp
->suspended
>= 0);
3872 fprintf (stderr
, " LWP %ld is suspended\n", lwpid_of (lwp
));
3876 if (thread
->last_resume_kind
== resume_stop
3877 && lwp
->pending_signals_to_report
== NULL
3878 && lwp
->collecting_fast_tracepoint
== 0)
3880 /* We haven't reported this LWP as stopped yet (otherwise, the
3881 last_status.kind check above would catch it, and we wouldn't
3882 reach here. This LWP may have been momentarily paused by a
3883 stop_all_lwps call while handling for example, another LWP's
3884 step-over. In that case, the pending expected SIGSTOP signal
3885 that was queued at vCont;t handling time will have already
3886 been consumed by wait_for_sigstop, and so we need to requeue
3887 another one here. Note that if the LWP already has a SIGSTOP
3888 pending, this is a no-op. */
3892 "Client wants LWP %ld to stop. "
3893 "Making sure it has a SIGSTOP pending\n",
3899 step
= thread
->last_resume_kind
== resume_step
;
3900 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3905 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3907 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3913 gdb_assert (lwp
->suspended
>= 0);
3915 return proceed_one_lwp (entry
, except
);
3918 /* When we finish a step-over, set threads running again. If there's
3919 another thread that may need a step-over, now's the time to start
3920 it. Eventually, we'll move all threads past their breakpoints. */
3923 proceed_all_lwps (void)
3925 struct lwp_info
*need_step_over
;
3927 /* If there is a thread which would otherwise be resumed, which is
3928 stopped at a breakpoint that needs stepping over, then don't
3929 resume any threads - have it step over the breakpoint with all
3930 other threads stopped, then resume all threads again. */
3932 if (supports_breakpoints ())
3935 = (struct lwp_info
*) find_inferior (&all_lwps
,
3936 need_step_over_p
, NULL
);
3938 if (need_step_over
!= NULL
)
3941 fprintf (stderr
, "proceed_all_lwps: found "
3942 "thread %ld needing a step-over\n",
3943 lwpid_of (need_step_over
));
3945 start_step_over (need_step_over
);
3951 fprintf (stderr
, "Proceeding, no step-over needed\n");
3953 find_inferior (&all_lwps
, proceed_one_lwp
, NULL
);
3956 /* Stopped LWPs that the client wanted to be running, that don't have
3957 pending statuses, are set to run again, except for EXCEPT, if not
3958 NULL. This undoes a stop_all_lwps call. */
3961 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
3967 "unstopping all lwps, except=(LWP %ld)\n", lwpid_of (except
));
3970 "unstopping all lwps\n");
3974 find_inferior (&all_lwps
, unsuspend_and_proceed_one_lwp
, except
);
3976 find_inferior (&all_lwps
, proceed_one_lwp
, except
);
3980 #ifdef HAVE_LINUX_REGSETS
3982 #define use_linux_regsets 1
3985 regsets_fetch_inferior_registers (struct regcache
*regcache
)
3987 struct regset_info
*regset
;
3988 int saw_general_regs
= 0;
3992 regset
= target_regsets
;
3994 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3995 while (regset
->size
>= 0)
4000 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
4006 buf
= xmalloc (regset
->size
);
4008 nt_type
= regset
->nt_type
;
4012 iov
.iov_len
= regset
->size
;
4013 data
= (void *) &iov
;
4019 res
= ptrace (regset
->get_request
, pid
,
4020 (PTRACE_ARG3_TYPE
) (long) nt_type
, data
);
4022 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4028 /* If we get EIO on a regset, do not try it again for
4030 disabled_regsets
[regset
- target_regsets
] = 1;
4037 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4042 else if (regset
->type
== GENERAL_REGS
)
4043 saw_general_regs
= 1;
4044 regset
->store_function (regcache
, buf
);
4048 if (saw_general_regs
)
4055 regsets_store_inferior_registers (struct regcache
*regcache
)
4057 struct regset_info
*regset
;
4058 int saw_general_regs
= 0;
4062 regset
= target_regsets
;
4064 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4065 while (regset
->size
>= 0)
4070 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
4076 buf
= xmalloc (regset
->size
);
4078 /* First fill the buffer with the current register set contents,
4079 in case there are any items in the kernel's regset that are
4080 not in gdbserver's regcache. */
4082 nt_type
= regset
->nt_type
;
4086 iov
.iov_len
= regset
->size
;
4087 data
= (void *) &iov
;
4093 res
= ptrace (regset
->get_request
, pid
,
4094 (PTRACE_ARG3_TYPE
) (long) nt_type
, data
);
4096 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4101 /* Then overlay our cached registers on that. */
4102 regset
->fill_function (regcache
, buf
);
4104 /* Only now do we write the register set. */
4106 res
= ptrace (regset
->set_request
, pid
,
4107 (PTRACE_ARG3_TYPE
) (long) nt_type
, data
);
4109 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4117 /* If we get EIO on a regset, do not try it again for
4119 disabled_regsets
[regset
- target_regsets
] = 1;
4123 else if (errno
== ESRCH
)
4125 /* At this point, ESRCH should mean the process is
4126 already gone, in which case we simply ignore attempts
4127 to change its registers. See also the related
4128 comment in linux_resume_one_lwp. */
4134 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4137 else if (regset
->type
== GENERAL_REGS
)
4138 saw_general_regs
= 1;
4142 if (saw_general_regs
)
4148 #else /* !HAVE_LINUX_REGSETS */
4150 #define use_linux_regsets 0
4151 #define regsets_fetch_inferior_registers(regcache) 1
4152 #define regsets_store_inferior_registers(regcache) 1
4156 /* Return 1 if register REGNO is supported by one of the regset ptrace
4157 calls or 0 if it has to be transferred individually. */
4160 linux_register_in_regsets (int regno
)
4162 unsigned char mask
= 1 << (regno
% 8);
4163 size_t index
= regno
/ 8;
4165 return (use_linux_regsets
4166 && (the_low_target
.regset_bitmap
== NULL
4167 || (the_low_target
.regset_bitmap
[index
] & mask
) != 0));
4170 #ifdef HAVE_LINUX_USRREGS
4173 register_addr (int regnum
)
4177 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
4178 error ("Invalid register number %d.", regnum
);
4180 addr
= the_low_target
.regmap
[regnum
];
4185 /* Fetch one register. */
4187 fetch_register (struct regcache
*regcache
, int regno
)
4194 if (regno
>= the_low_target
.num_regs
)
4196 if ((*the_low_target
.cannot_fetch_register
) (regno
))
4199 regaddr
= register_addr (regno
);
4203 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4204 & -sizeof (PTRACE_XFER_TYPE
));
4205 buf
= alloca (size
);
4207 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4208 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4211 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
4212 ptrace (PTRACE_PEEKUSER
, pid
,
4213 /* Coerce to a uintptr_t first to avoid potential gcc warning
4214 of coercing an 8 byte integer to a 4 byte pointer. */
4215 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
, 0);
4216 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4218 error ("reading register %d: %s", regno
, strerror (errno
));
4221 if (the_low_target
.supply_ptrace_register
)
4222 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
4224 supply_register (regcache
, regno
, buf
);
4227 /* Store one register. */
4229 store_register (struct regcache
*regcache
, int regno
)
4236 if (regno
>= the_low_target
.num_regs
)
4238 if ((*the_low_target
.cannot_store_register
) (regno
))
4241 regaddr
= register_addr (regno
);
4245 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4246 & -sizeof (PTRACE_XFER_TYPE
));
4247 buf
= alloca (size
);
4248 memset (buf
, 0, size
);
4250 if (the_low_target
.collect_ptrace_register
)
4251 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
4253 collect_register (regcache
, regno
, buf
);
4255 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4256 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4259 ptrace (PTRACE_POKEUSER
, pid
,
4260 /* Coerce to a uintptr_t first to avoid potential gcc warning
4261 about coercing an 8 byte integer to a 4 byte pointer. */
4262 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
,
4263 (PTRACE_ARG4_TYPE
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
4266 /* At this point, ESRCH should mean the process is
4267 already gone, in which case we simply ignore attempts
4268 to change its registers. See also the related
4269 comment in linux_resume_one_lwp. */
4273 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
4274 error ("writing register %d: %s", regno
, strerror (errno
));
4276 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4280 /* Fetch all registers, or just one, from the child process.
4281 If REGNO is -1, do this for all registers, skipping any that are
4282 assumed to have been retrieved by regsets_fetch_inferior_registers,
4283 unless ALL is non-zero.
4284 Otherwise, REGNO specifies which register (so we can save time). */
4286 usr_fetch_inferior_registers (struct regcache
*regcache
, int regno
, int all
)
4290 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4291 if (all
|| !linux_register_in_regsets (regno
))
4292 fetch_register (regcache
, regno
);
4295 fetch_register (regcache
, regno
);
4298 /* Store our register values back into the inferior.
4299 If REGNO is -1, do this for all registers, skipping any that are
4300 assumed to have been saved by regsets_store_inferior_registers,
4301 unless ALL is non-zero.
4302 Otherwise, REGNO specifies which register (so we can save time). */
4304 usr_store_inferior_registers (struct regcache
*regcache
, int regno
, int all
)
4308 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4309 if (all
|| !linux_register_in_regsets (regno
))
4310 store_register (regcache
, regno
);
4313 store_register (regcache
, regno
);
4316 #else /* !HAVE_LINUX_USRREGS */
4318 #define usr_fetch_inferior_registers(regcache, regno, all) do {} while (0)
4319 #define usr_store_inferior_registers(regcache, regno, all) do {} while (0)
4325 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4332 if (the_low_target
.fetch_register
!= NULL
)
4333 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4334 (*the_low_target
.fetch_register
) (regcache
, regno
);
4336 all
= regsets_fetch_inferior_registers (regcache
);
4337 usr_fetch_inferior_registers (regcache
, -1, all
);
4341 if (the_low_target
.fetch_register
!= NULL
4342 && (*the_low_target
.fetch_register
) (regcache
, regno
))
4345 use_regsets
= linux_register_in_regsets (regno
);
4347 all
= regsets_fetch_inferior_registers (regcache
);
4348 if (!use_regsets
|| all
)
4349 usr_fetch_inferior_registers (regcache
, regno
, 1);
4354 linux_store_registers (struct regcache
*regcache
, int regno
)
4361 all
= regsets_store_inferior_registers (regcache
);
4362 usr_store_inferior_registers (regcache
, regno
, all
);
4366 use_regsets
= linux_register_in_regsets (regno
);
4368 all
= regsets_store_inferior_registers (regcache
);
4369 if (!use_regsets
|| all
)
4370 usr_store_inferior_registers (regcache
, regno
, 1);
4375 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4376 to debugger memory starting at MYADDR. */
4379 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4382 /* Round starting address down to longword boundary. */
4383 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4384 /* Round ending address up; get number of longwords that makes. */
4386 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4387 / sizeof (PTRACE_XFER_TYPE
);
4388 /* Allocate buffer of that many longwords. */
4389 register PTRACE_XFER_TYPE
*buffer
4390 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4393 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4395 /* Try using /proc. Don't bother for one word. */
4396 if (len
>= 3 * sizeof (long))
4398 /* We could keep this file open and cache it - possibly one per
4399 thread. That requires some juggling, but is even faster. */
4400 sprintf (filename
, "/proc/%d/mem", pid
);
4401 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4405 /* If pread64 is available, use it. It's faster if the kernel
4406 supports it (only one syscall), and it's 64-bit safe even on
4407 32-bit platforms (for instance, SPARC debugging a SPARC64
4410 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
4412 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, myaddr
, len
) != len
)
4424 /* Read all the longwords */
4425 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4428 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4429 about coercing an 8 byte integer to a 4 byte pointer. */
4430 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4431 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4436 /* Copy appropriate bytes out of the buffer. */
4438 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4444 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4445 memory at MEMADDR. On failure (cannot write to the inferior)
4446 returns the value of errno. */
4449 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4452 /* Round starting address down to longword boundary. */
4453 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4454 /* Round ending address up; get number of longwords that makes. */
4456 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4457 / sizeof (PTRACE_XFER_TYPE
);
4459 /* Allocate buffer of that many longwords. */
4460 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4461 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4463 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4467 /* Dump up to four bytes. */
4468 unsigned int val
= * (unsigned int *) myaddr
;
4474 val
= val
& 0xffffff;
4475 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4476 val
, (long)memaddr
);
4479 /* Fill start and end extra bytes of buffer with existing memory data. */
4482 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4483 about coercing an 8 byte integer to a 4 byte pointer. */
4484 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4485 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4493 = ptrace (PTRACE_PEEKTEXT
, pid
,
4494 /* Coerce to a uintptr_t first to avoid potential gcc warning
4495 about coercing an 8 byte integer to a 4 byte pointer. */
4496 (PTRACE_ARG3_TYPE
) (uintptr_t) (addr
+ (count
- 1)
4497 * sizeof (PTRACE_XFER_TYPE
)),
4503 /* Copy data to be written over corresponding part of buffer. */
4505 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4508 /* Write the entire buffer. */
4510 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4513 ptrace (PTRACE_POKETEXT
, pid
,
4514 /* Coerce to a uintptr_t first to avoid potential gcc warning
4515 about coercing an 8 byte integer to a 4 byte pointer. */
4516 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
4517 (PTRACE_ARG4_TYPE
) buffer
[i
]);
4525 /* Non-zero if the kernel supports PTRACE_O_TRACEFORK. */
4526 static int linux_supports_tracefork_flag
;
4529 linux_enable_event_reporting (int pid
)
4531 if (!linux_supports_tracefork_flag
)
4534 ptrace (PTRACE_SETOPTIONS
, pid
, 0, (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
4537 /* Helper functions for linux_test_for_tracefork, called via clone (). */
4540 linux_tracefork_grandchild (void *arg
)
4545 #define STACK_SIZE 4096
4548 linux_tracefork_child (void *arg
)
4550 ptrace (PTRACE_TRACEME
, 0, 0, 0);
4551 kill (getpid (), SIGSTOP
);
4553 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4556 linux_tracefork_grandchild (NULL
);
4558 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4561 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
4562 CLONE_VM
| SIGCHLD
, NULL
);
4564 clone (linux_tracefork_grandchild
, (char *) arg
+ STACK_SIZE
,
4565 CLONE_VM
| SIGCHLD
, NULL
);
4568 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4573 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
4574 sure that we can enable the option, and that it had the desired
4578 linux_test_for_tracefork (void)
4580 int child_pid
, ret
, status
;
4582 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4583 char *stack
= xmalloc (STACK_SIZE
* 4);
4584 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4586 linux_supports_tracefork_flag
= 0;
4588 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4590 child_pid
= fork ();
4592 linux_tracefork_child (NULL
);
4594 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4596 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
4598 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
4599 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4600 #else /* !__ia64__ */
4601 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
4602 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4603 #endif /* !__ia64__ */
4605 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4607 if (child_pid
== -1)
4608 perror_with_name ("clone");
4610 ret
= my_waitpid (child_pid
, &status
, 0);
4612 perror_with_name ("waitpid");
4613 else if (ret
!= child_pid
)
4614 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
4615 if (! WIFSTOPPED (status
))
4616 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
4618 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
4619 (PTRACE_ARG4_TYPE
) PTRACE_O_TRACEFORK
);
4622 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4625 warning ("linux_test_for_tracefork: failed to kill child");
4629 ret
= my_waitpid (child_pid
, &status
, 0);
4630 if (ret
!= child_pid
)
4631 warning ("linux_test_for_tracefork: failed to wait for killed child");
4632 else if (!WIFSIGNALED (status
))
4633 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
4634 "killed child", status
);
4639 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
4641 warning ("linux_test_for_tracefork: failed to resume child");
4643 ret
= my_waitpid (child_pid
, &status
, 0);
4645 if (ret
== child_pid
&& WIFSTOPPED (status
)
4646 && status
>> 16 == PTRACE_EVENT_FORK
)
4649 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
4650 if (ret
== 0 && second_pid
!= 0)
4654 linux_supports_tracefork_flag
= 1;
4655 my_waitpid (second_pid
, &second_status
, 0);
4656 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
4658 warning ("linux_test_for_tracefork: failed to kill second child");
4659 my_waitpid (second_pid
, &status
, 0);
4663 warning ("linux_test_for_tracefork: unexpected result from waitpid "
4664 "(%d, status 0x%x)", ret
, status
);
4668 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4670 warning ("linux_test_for_tracefork: failed to kill child");
4671 my_waitpid (child_pid
, &status
, 0);
4673 while (WIFSTOPPED (status
));
4675 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4677 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4682 linux_look_up_symbols (void)
4684 #ifdef USE_THREAD_DB
4685 struct process_info
*proc
= current_process ();
4687 if (proc
->private->thread_db
!= NULL
)
4690 /* If the kernel supports tracing forks then it also supports tracing
4691 clones, and then we don't need to use the magic thread event breakpoint
4692 to learn about threads. */
4693 thread_db_init (!linux_supports_tracefork_flag
);
4698 linux_request_interrupt (void)
4700 extern unsigned long signal_pid
;
4702 if (!ptid_equal (cont_thread
, null_ptid
)
4703 && !ptid_equal (cont_thread
, minus_one_ptid
))
4705 struct lwp_info
*lwp
;
4708 lwp
= get_thread_lwp (current_inferior
);
4709 lwpid
= lwpid_of (lwp
);
4710 kill_lwp (lwpid
, SIGINT
);
4713 kill_lwp (signal_pid
, SIGINT
);
4716 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4717 to debugger memory starting at MYADDR. */
4720 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4722 char filename
[PATH_MAX
];
4724 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4726 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4728 fd
= open (filename
, O_RDONLY
);
4732 if (offset
!= (CORE_ADDR
) 0
4733 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4736 n
= read (fd
, myaddr
, len
);
4743 /* These breakpoint and watchpoint related wrapper functions simply
4744 pass on the function call if the target has registered a
4745 corresponding function. */
4748 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
4750 if (the_low_target
.insert_point
!= NULL
)
4751 return the_low_target
.insert_point (type
, addr
, len
);
4753 /* Unsupported (see target.h). */
4758 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
4760 if (the_low_target
.remove_point
!= NULL
)
4761 return the_low_target
.remove_point (type
, addr
, len
);
4763 /* Unsupported (see target.h). */
4768 linux_stopped_by_watchpoint (void)
4770 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4772 return lwp
->stopped_by_watchpoint
;
4776 linux_stopped_data_address (void)
4778 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4780 return lwp
->stopped_data_address
;
4783 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4784 #if defined(__mcoldfire__)
4785 /* These should really be defined in the kernel's ptrace.h header. */
4786 #define PT_TEXT_ADDR 49*4
4787 #define PT_DATA_ADDR 50*4
4788 #define PT_TEXT_END_ADDR 51*4
4790 #define PT_TEXT_ADDR 220
4791 #define PT_TEXT_END_ADDR 224
4792 #define PT_DATA_ADDR 228
4793 #elif defined(__TMS320C6X__)
4794 #define PT_TEXT_ADDR (0x10000*4)
4795 #define PT_DATA_ADDR (0x10004*4)
4796 #define PT_TEXT_END_ADDR (0x10008*4)
4799 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4800 to tell gdb about. */
4803 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
4805 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
4806 unsigned long text
, text_end
, data
;
4807 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4811 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
4812 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
4813 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
4817 /* Both text and data offsets produced at compile-time (and so
4818 used by gdb) are relative to the beginning of the program,
4819 with the data segment immediately following the text segment.
4820 However, the actual runtime layout in memory may put the data
4821 somewhere else, so when we send gdb a data base-address, we
4822 use the real data base address and subtract the compile-time
4823 data base-address from it (which is just the length of the
4824 text segment). BSS immediately follows data in both
4827 *data_p
= data
- (text_end
- text
);
4837 linux_qxfer_osdata (const char *annex
,
4838 unsigned char *readbuf
, unsigned const char *writebuf
,
4839 CORE_ADDR offset
, int len
)
4841 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
4844 /* Convert a native/host siginfo object, into/from the siginfo in the
4845 layout of the inferiors' architecture. */
4848 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
4852 if (the_low_target
.siginfo_fixup
!= NULL
)
4853 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4855 /* If there was no callback, or the callback didn't do anything,
4856 then just do a straight memcpy. */
4860 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
4862 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
4867 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
4868 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
4872 char inf_siginfo
[sizeof (siginfo_t
)];
4874 if (current_inferior
== NULL
)
4877 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4880 fprintf (stderr
, "%s siginfo for lwp %d.\n",
4881 readbuf
!= NULL
? "Reading" : "Writing",
4884 if (offset
>= sizeof (siginfo
))
4887 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
4890 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4891 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4892 inferior with a 64-bit GDBSERVER should look the same as debugging it
4893 with a 32-bit GDBSERVER, we need to convert it. */
4894 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4896 if (offset
+ len
> sizeof (siginfo
))
4897 len
= sizeof (siginfo
) - offset
;
4899 if (readbuf
!= NULL
)
4900 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4903 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4905 /* Convert back to ptrace layout before flushing it out. */
4906 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4908 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
4915 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4916 so we notice when children change state; as the handler for the
4917 sigsuspend in my_waitpid. */
4920 sigchld_handler (int signo
)
4922 int old_errno
= errno
;
4928 /* fprintf is not async-signal-safe, so call write
4930 if (write (2, "sigchld_handler\n",
4931 sizeof ("sigchld_handler\n") - 1) < 0)
4932 break; /* just ignore */
4936 if (target_is_async_p ())
4937 async_file_mark (); /* trigger a linux_wait */
4943 linux_supports_non_stop (void)
4949 linux_async (int enable
)
4951 int previous
= (linux_event_pipe
[0] != -1);
4954 fprintf (stderr
, "linux_async (%d), previous=%d\n",
4957 if (previous
!= enable
)
4960 sigemptyset (&mask
);
4961 sigaddset (&mask
, SIGCHLD
);
4963 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
4967 if (pipe (linux_event_pipe
) == -1)
4968 fatal ("creating event pipe failed.");
4970 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
4971 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
4973 /* Register the event loop handler. */
4974 add_file_handler (linux_event_pipe
[0],
4975 handle_target_event
, NULL
);
4977 /* Always trigger a linux_wait. */
4982 delete_file_handler (linux_event_pipe
[0]);
4984 close (linux_event_pipe
[0]);
4985 close (linux_event_pipe
[1]);
4986 linux_event_pipe
[0] = -1;
4987 linux_event_pipe
[1] = -1;
4990 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
4997 linux_start_non_stop (int nonstop
)
4999 /* Register or unregister from event-loop accordingly. */
5000 linux_async (nonstop
);
5005 linux_supports_multi_process (void)
5011 linux_supports_disable_randomization (void)
5013 #ifdef HAVE_PERSONALITY
5021 linux_supports_agent (void)
5026 /* Enumerate spufs IDs for process PID. */
5028 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
5034 struct dirent
*entry
;
5036 sprintf (path
, "/proc/%ld/fd", pid
);
5037 dir
= opendir (path
);
5042 while ((entry
= readdir (dir
)) != NULL
)
5048 fd
= atoi (entry
->d_name
);
5052 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
5053 if (stat (path
, &st
) != 0)
5055 if (!S_ISDIR (st
.st_mode
))
5058 if (statfs (path
, &stfs
) != 0)
5060 if (stfs
.f_type
!= SPUFS_MAGIC
)
5063 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
5065 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
5075 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
5076 object type, using the /proc file system. */
5078 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
5079 unsigned const char *writebuf
,
5080 CORE_ADDR offset
, int len
)
5082 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
5087 if (!writebuf
&& !readbuf
)
5095 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5098 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
5099 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5104 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5111 ret
= write (fd
, writebuf
, (size_t) len
);
5113 ret
= read (fd
, readbuf
, (size_t) len
);
5119 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5120 struct target_loadseg
5122 /* Core address to which the segment is mapped. */
5124 /* VMA recorded in the program header. */
5126 /* Size of this segment in memory. */
5130 # if defined PT_GETDSBT
5131 struct target_loadmap
5133 /* Protocol version number, must be zero. */
5135 /* Pointer to the DSBT table, its size, and the DSBT index. */
5136 unsigned *dsbt_table
;
5137 unsigned dsbt_size
, dsbt_index
;
5138 /* Number of segments in this map. */
5140 /* The actual memory map. */
5141 struct target_loadseg segs
[/*nsegs*/];
5143 # define LINUX_LOADMAP PT_GETDSBT
5144 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5145 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5147 struct target_loadmap
5149 /* Protocol version number, must be zero. */
5151 /* Number of segments in this map. */
5153 /* The actual memory map. */
5154 struct target_loadseg segs
[/*nsegs*/];
5156 # define LINUX_LOADMAP PTRACE_GETFDPIC
5157 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5158 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5162 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
5163 unsigned char *myaddr
, unsigned int len
)
5165 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
5167 struct target_loadmap
*data
= NULL
;
5168 unsigned int actual_length
, copy_length
;
5170 if (strcmp (annex
, "exec") == 0)
5171 addr
= (int) LINUX_LOADMAP_EXEC
;
5172 else if (strcmp (annex
, "interp") == 0)
5173 addr
= (int) LINUX_LOADMAP_INTERP
;
5177 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
5183 actual_length
= sizeof (struct target_loadmap
)
5184 + sizeof (struct target_loadseg
) * data
->nsegs
;
5186 if (offset
< 0 || offset
> actual_length
)
5189 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
5190 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
5194 # define linux_read_loadmap NULL
5195 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5198 linux_process_qsupported (const char *query
)
5200 if (the_low_target
.process_qsupported
!= NULL
)
5201 the_low_target
.process_qsupported (query
);
5205 linux_supports_tracepoints (void)
5207 if (*the_low_target
.supports_tracepoints
== NULL
)
5210 return (*the_low_target
.supports_tracepoints
) ();
5214 linux_read_pc (struct regcache
*regcache
)
5216 if (the_low_target
.get_pc
== NULL
)
5219 return (*the_low_target
.get_pc
) (regcache
);
5223 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
5225 gdb_assert (the_low_target
.set_pc
!= NULL
);
5227 (*the_low_target
.set_pc
) (regcache
, pc
);
5231 linux_thread_stopped (struct thread_info
*thread
)
5233 return get_thread_lwp (thread
)->stopped
;
5236 /* This exposes stop-all-threads functionality to other modules. */
5239 linux_pause_all (int freeze
)
5241 stop_all_lwps (freeze
, NULL
);
5244 /* This exposes unstop-all-threads functionality to other gdbserver
5248 linux_unpause_all (int unfreeze
)
5250 unstop_all_lwps (unfreeze
, NULL
);
5254 linux_prepare_to_access_memory (void)
5256 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5259 linux_pause_all (1);
5264 linux_done_accessing_memory (void)
5266 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5269 linux_unpause_all (1);
5273 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5274 CORE_ADDR collector
,
5277 CORE_ADDR
*jump_entry
,
5278 CORE_ADDR
*trampoline
,
5279 ULONGEST
*trampoline_size
,
5280 unsigned char *jjump_pad_insn
,
5281 ULONGEST
*jjump_pad_insn_size
,
5282 CORE_ADDR
*adjusted_insn_addr
,
5283 CORE_ADDR
*adjusted_insn_addr_end
,
5286 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5287 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5288 jump_entry
, trampoline
, trampoline_size
,
5289 jjump_pad_insn
, jjump_pad_insn_size
,
5290 adjusted_insn_addr
, adjusted_insn_addr_end
,
5294 static struct emit_ops
*
5295 linux_emit_ops (void)
5297 if (the_low_target
.emit_ops
!= NULL
)
5298 return (*the_low_target
.emit_ops
) ();
5304 linux_get_min_fast_tracepoint_insn_len (void)
5306 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5309 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5312 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5313 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5315 char filename
[PATH_MAX
];
5317 const int auxv_size
= is_elf64
5318 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5319 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5321 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5323 fd
= open (filename
, O_RDONLY
);
5329 while (read (fd
, buf
, auxv_size
) == auxv_size
5330 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5334 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5336 switch (aux
->a_type
)
5339 *phdr_memaddr
= aux
->a_un
.a_val
;
5342 *num_phdr
= aux
->a_un
.a_val
;
5348 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5350 switch (aux
->a_type
)
5353 *phdr_memaddr
= aux
->a_un
.a_val
;
5356 *num_phdr
= aux
->a_un
.a_val
;
5364 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5366 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5367 "phdr_memaddr = %ld, phdr_num = %d",
5368 (long) *phdr_memaddr
, *num_phdr
);
5375 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5378 get_dynamic (const int pid
, const int is_elf64
)
5380 CORE_ADDR phdr_memaddr
, relocation
;
5382 unsigned char *phdr_buf
;
5383 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5385 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5388 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5389 phdr_buf
= alloca (num_phdr
* phdr_size
);
5391 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5394 /* Compute relocation: it is expected to be 0 for "regular" executables,
5395 non-zero for PIE ones. */
5397 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5400 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5402 if (p
->p_type
== PT_PHDR
)
5403 relocation
= phdr_memaddr
- p
->p_vaddr
;
5407 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5409 if (p
->p_type
== PT_PHDR
)
5410 relocation
= phdr_memaddr
- p
->p_vaddr
;
5413 if (relocation
== -1)
5415 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5416 any real world executables, including PIE executables, have always
5417 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5418 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5419 or present DT_DEBUG anyway (fpc binaries are statically linked).
5421 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5423 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5428 for (i
= 0; i
< num_phdr
; i
++)
5432 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5434 if (p
->p_type
== PT_DYNAMIC
)
5435 return p
->p_vaddr
+ relocation
;
5439 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5441 if (p
->p_type
== PT_DYNAMIC
)
5442 return p
->p_vaddr
+ relocation
;
5449 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5450 can be 0 if the inferior does not yet have the library list initialized.
5451 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
5452 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
5455 get_r_debug (const int pid
, const int is_elf64
)
5457 CORE_ADDR dynamic_memaddr
;
5458 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5459 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5462 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5463 if (dynamic_memaddr
== 0)
5466 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5470 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5474 unsigned char buf
[sizeof (Elf64_Xword
)];
5478 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5480 if (linux_read_memory (dyn
->d_un
.d_val
,
5481 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5487 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5488 map
= dyn
->d_un
.d_val
;
5490 if (dyn
->d_tag
== DT_NULL
)
5495 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5499 unsigned char buf
[sizeof (Elf32_Word
)];
5503 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5505 if (linux_read_memory (dyn
->d_un
.d_val
,
5506 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5512 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5513 map
= dyn
->d_un
.d_val
;
5515 if (dyn
->d_tag
== DT_NULL
)
5519 dynamic_memaddr
+= dyn_size
;
5525 /* Read one pointer from MEMADDR in the inferior. */
5528 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5532 /* Go through a union so this works on either big or little endian
5533 hosts, when the inferior's pointer size is smaller than the size
5534 of CORE_ADDR. It is assumed the inferior's endianness is the
5535 same of the superior's. */
5538 CORE_ADDR core_addr
;
5543 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
5546 if (ptr_size
== sizeof (CORE_ADDR
))
5547 *ptr
= addr
.core_addr
;
5548 else if (ptr_size
== sizeof (unsigned int))
5551 gdb_assert_not_reached ("unhandled pointer size");
5556 struct link_map_offsets
5558 /* Offset and size of r_debug.r_version. */
5559 int r_version_offset
;
5561 /* Offset and size of r_debug.r_map. */
5564 /* Offset to l_addr field in struct link_map. */
5567 /* Offset to l_name field in struct link_map. */
5570 /* Offset to l_ld field in struct link_map. */
5573 /* Offset to l_next field in struct link_map. */
5576 /* Offset to l_prev field in struct link_map. */
5580 /* Construct qXfer:libraries-svr4:read reply. */
5583 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5584 unsigned const char *writebuf
,
5585 CORE_ADDR offset
, int len
)
5588 unsigned document_len
;
5589 struct process_info_private
*const priv
= current_process ()->private;
5590 char filename
[PATH_MAX
];
5593 static const struct link_map_offsets lmo_32bit_offsets
=
5595 0, /* r_version offset. */
5596 4, /* r_debug.r_map offset. */
5597 0, /* l_addr offset in link_map. */
5598 4, /* l_name offset in link_map. */
5599 8, /* l_ld offset in link_map. */
5600 12, /* l_next offset in link_map. */
5601 16 /* l_prev offset in link_map. */
5604 static const struct link_map_offsets lmo_64bit_offsets
=
5606 0, /* r_version offset. */
5607 8, /* r_debug.r_map offset. */
5608 0, /* l_addr offset in link_map. */
5609 8, /* l_name offset in link_map. */
5610 16, /* l_ld offset in link_map. */
5611 24, /* l_next offset in link_map. */
5612 32 /* l_prev offset in link_map. */
5614 const struct link_map_offsets
*lmo
;
5615 unsigned int machine
;
5617 if (writebuf
!= NULL
)
5619 if (readbuf
== NULL
)
5622 pid
= lwpid_of (get_thread_lwp (current_inferior
));
5623 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5624 is_elf64
= elf_64_file_p (filename
, &machine
);
5625 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5627 if (priv
->r_debug
== 0)
5628 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5630 if (priv
->r_debug
== (CORE_ADDR
) -1 || priv
->r_debug
== 0)
5632 document
= xstrdup ("<library-list-svr4 version=\"1.0\"/>\n");
5636 int allocated
= 1024;
5638 const int ptr_size
= is_elf64
? 8 : 4;
5639 CORE_ADDR lm_addr
, lm_prev
, l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5640 int r_version
, header_done
= 0;
5642 document
= xmalloc (allocated
);
5643 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5644 p
= document
+ strlen (document
);
5647 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5648 (unsigned char *) &r_version
,
5649 sizeof (r_version
)) != 0
5652 warning ("unexpected r_debug version %d", r_version
);
5656 if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5657 &lm_addr
, ptr_size
) != 0)
5659 warning ("unable to read r_map from 0x%lx",
5660 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5665 while (read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5666 &l_name
, ptr_size
) == 0
5667 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5668 &l_addr
, ptr_size
) == 0
5669 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5670 &l_ld
, ptr_size
) == 0
5671 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5672 &l_prev
, ptr_size
) == 0
5673 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5674 &l_next
, ptr_size
) == 0)
5676 unsigned char libname
[PATH_MAX
];
5678 if (lm_prev
!= l_prev
)
5680 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5681 (long) lm_prev
, (long) l_prev
);
5685 /* Not checking for error because reading may stop before
5686 we've got PATH_MAX worth of characters. */
5688 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5689 libname
[sizeof (libname
) - 1] = '\0';
5690 if (libname
[0] != '\0')
5692 /* 6x the size for xml_escape_text below. */
5693 size_t len
= 6 * strlen ((char *) libname
);
5698 /* Terminate `<library-list-svr4'. */
5703 while (allocated
< p
- document
+ len
+ 200)
5705 /* Expand to guarantee sufficient storage. */
5706 uintptr_t document_len
= p
- document
;
5708 document
= xrealloc (document
, 2 * allocated
);
5710 p
= document
+ document_len
;
5713 name
= xml_escape_text ((char *) libname
);
5714 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
5715 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5716 name
, (unsigned long) lm_addr
,
5717 (unsigned long) l_addr
, (unsigned long) l_ld
);
5720 else if (lm_prev
== 0)
5722 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5735 /* Empty list; terminate `<library-list-svr4'. */
5739 strcpy (p
, "</library-list-svr4>");
5742 document_len
= strlen (document
);
5743 if (offset
< document_len
)
5744 document_len
-= offset
;
5747 if (len
> document_len
)
5750 memcpy (readbuf
, document
+ offset
, len
);
5756 static struct target_ops linux_target_ops
= {
5757 linux_create_inferior
,
5766 linux_fetch_registers
,
5767 linux_store_registers
,
5768 linux_prepare_to_access_memory
,
5769 linux_done_accessing_memory
,
5772 linux_look_up_symbols
,
5773 linux_request_interrupt
,
5777 linux_stopped_by_watchpoint
,
5778 linux_stopped_data_address
,
5779 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
5784 #ifdef USE_THREAD_DB
5785 thread_db_get_tls_address
,
5790 hostio_last_error_from_errno
,
5793 linux_supports_non_stop
,
5795 linux_start_non_stop
,
5796 linux_supports_multi_process
,
5797 #ifdef USE_THREAD_DB
5798 thread_db_handle_monitor_command
,
5802 linux_common_core_of_thread
,
5804 linux_process_qsupported
,
5805 linux_supports_tracepoints
,
5808 linux_thread_stopped
,
5812 linux_cancel_breakpoints
,
5813 linux_stabilize_threads
,
5814 linux_install_fast_tracepoint_jump_pad
,
5816 linux_supports_disable_randomization
,
5817 linux_get_min_fast_tracepoint_insn_len
,
5818 linux_qxfer_libraries_svr4
,
5819 linux_supports_agent
,
5823 linux_init_signals ()
5825 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5826 to find what the cancel signal actually is. */
5827 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
5828 signal (__SIGRTMIN
+1, SIG_IGN
);
5833 initialize_low (void)
5835 struct sigaction sigchld_action
;
5836 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
5837 set_target_ops (&linux_target_ops
);
5838 set_breakpoint_data (the_low_target
.breakpoint
,
5839 the_low_target
.breakpoint_len
);
5840 linux_init_signals ();
5841 linux_test_for_tracefork ();
5842 #ifdef HAVE_LINUX_REGSETS
5843 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
5845 disabled_regsets
= xmalloc (num_regsets
);
5848 sigchld_action
.sa_handler
= sigchld_handler
;
5849 sigemptyset (&sigchld_action
.sa_mask
);
5850 sigchld_action
.sa_flags
= SA_RESTART
;
5851 sigaction (SIGCHLD
, &sigchld_action
, NULL
);