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 /* FIXME this is a bit of a hack, and could be removed. */
176 int stopping_threads
;
178 /* FIXME make into a target method? */
179 int using_threads
= 1;
181 /* True if we're presently stabilizing threads (moving them out of
183 static int stabilizing_threads
;
185 /* This flag is true iff we've just created or attached to our first
186 inferior but it has not stopped yet. As soon as it does, we need
187 to call the low target's arch_setup callback. Doing this only on
188 the first inferior avoids reinializing the architecture on every
189 inferior, and avoids messing with the register caches of the
190 already running inferiors. NOTE: this assumes all inferiors under
191 control of gdbserver have the same architecture. */
192 static int new_inferior
;
194 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
195 int step
, int signal
, siginfo_t
*info
);
196 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
197 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
198 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
199 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
200 static void *add_lwp (ptid_t ptid
);
201 static int linux_stopped_by_watchpoint (void);
202 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
203 static void proceed_all_lwps (void);
204 static int finish_step_over (struct lwp_info
*lwp
);
205 static CORE_ADDR
get_stop_pc (struct lwp_info
*lwp
);
206 static int kill_lwp (unsigned long lwpid
, int signo
);
207 static void linux_enable_event_reporting (int pid
);
209 /* True if the low target can hardware single-step. Such targets
210 don't need a BREAKPOINT_REINSERT_ADDR callback. */
213 can_hardware_single_step (void)
215 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
218 /* True if the low target supports memory breakpoints. If so, we'll
219 have a GET_PC implementation. */
222 supports_breakpoints (void)
224 return (the_low_target
.get_pc
!= NULL
);
227 /* Returns true if this target can support fast tracepoints. This
228 does not mean that the in-process agent has been loaded in the
232 supports_fast_tracepoints (void)
234 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
237 struct pending_signals
241 struct pending_signals
*prev
;
244 #ifdef HAVE_LINUX_REGSETS
245 static char *disabled_regsets
;
246 static int num_regsets
;
249 /* The read/write ends of the pipe registered as waitable file in the
251 static int linux_event_pipe
[2] = { -1, -1 };
253 /* True if we're currently in async mode. */
254 #define target_is_async_p() (linux_event_pipe[0] != -1)
256 static void send_sigstop (struct lwp_info
*lwp
);
257 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
259 /* Return non-zero if HEADER is a 64-bit ELF file. */
262 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
264 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
265 && header
->e_ident
[EI_MAG1
] == ELFMAG1
266 && header
->e_ident
[EI_MAG2
] == ELFMAG2
267 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
269 *machine
= header
->e_machine
;
270 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
277 /* Return non-zero if FILE is a 64-bit ELF file,
278 zero if the file is not a 64-bit ELF file,
279 and -1 if the file is not accessible or doesn't exist. */
282 elf_64_file_p (const char *file
, unsigned int *machine
)
287 fd
= open (file
, O_RDONLY
);
291 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
298 return elf_64_header_p (&header
, machine
);
301 /* Accepts an integer PID; Returns true if the executable PID is
302 running is a 64-bit ELF file.. */
305 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
307 char file
[MAXPATHLEN
];
309 sprintf (file
, "/proc/%d/exe", pid
);
310 return elf_64_file_p (file
, machine
);
314 delete_lwp (struct lwp_info
*lwp
)
316 remove_thread (get_lwp_thread (lwp
));
317 remove_inferior (&all_lwps
, &lwp
->head
);
318 free (lwp
->arch_private
);
322 /* Add a process to the common process list, and set its private
325 static struct process_info
*
326 linux_add_process (int pid
, int attached
)
328 struct process_info
*proc
;
330 /* Is this the first process? If so, then set the arch. */
331 if (all_processes
.head
== NULL
)
334 proc
= add_process (pid
, attached
);
335 proc
->private = xcalloc (1, sizeof (*proc
->private));
337 if (the_low_target
.new_process
!= NULL
)
338 proc
->private->arch_private
= the_low_target
.new_process ();
343 /* Wrapper function for waitpid which handles EINTR, and emulates
344 __WALL for systems where that is not available. */
347 my_waitpid (int pid
, int *status
, int flags
)
352 fprintf (stderr
, "my_waitpid (%d, 0x%x)\n", pid
, flags
);
356 sigset_t block_mask
, org_mask
, wake_mask
;
359 wnohang
= (flags
& WNOHANG
) != 0;
360 flags
&= ~(__WALL
| __WCLONE
);
363 /* Block all signals while here. This avoids knowing about
364 LinuxThread's signals. */
365 sigfillset (&block_mask
);
366 sigprocmask (SIG_BLOCK
, &block_mask
, &org_mask
);
368 /* ... except during the sigsuspend below. */
369 sigemptyset (&wake_mask
);
373 /* Since all signals are blocked, there's no need to check
375 ret
= waitpid (pid
, status
, flags
);
378 if (ret
== -1 && out_errno
!= ECHILD
)
383 if (flags
& __WCLONE
)
385 /* We've tried both flavors now. If WNOHANG is set,
386 there's nothing else to do, just bail out. */
391 fprintf (stderr
, "blocking\n");
393 /* Block waiting for signals. */
394 sigsuspend (&wake_mask
);
400 sigprocmask (SIG_SETMASK
, &org_mask
, NULL
);
405 ret
= waitpid (pid
, status
, flags
);
406 while (ret
== -1 && errno
== EINTR
);
411 fprintf (stderr
, "my_waitpid (%d, 0x%x): status(%x), %d\n",
412 pid
, flags
, status
? *status
: -1, ret
);
418 /* Handle a GNU/Linux extended wait response. If we see a clone
419 event, we need to add the new LWP to our list (and not report the
420 trap to higher layers). */
423 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
425 int event
= wstat
>> 16;
426 struct lwp_info
*new_lwp
;
428 if (event
== PTRACE_EVENT_CLONE
)
431 unsigned long new_pid
;
434 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), 0, &new_pid
);
436 /* If we haven't already seen the new PID stop, wait for it now. */
437 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
439 /* The new child has a pending SIGSTOP. We can't affect it until it
440 hits the SIGSTOP, but we're already attached. */
442 ret
= my_waitpid (new_pid
, &status
, __WALL
);
445 perror_with_name ("waiting for new child");
446 else if (ret
!= new_pid
)
447 warning ("wait returned unexpected PID %d", ret
);
448 else if (!WIFSTOPPED (status
))
449 warning ("wait returned unexpected status 0x%x", status
);
452 linux_enable_event_reporting (new_pid
);
454 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
455 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
456 add_thread (ptid
, new_lwp
);
458 /* Either we're going to immediately resume the new thread
459 or leave it stopped. linux_resume_one_lwp is a nop if it
460 thinks the thread is currently running, so set this first
461 before calling linux_resume_one_lwp. */
462 new_lwp
->stopped
= 1;
464 /* Normally we will get the pending SIGSTOP. But in some cases
465 we might get another signal delivered to the group first.
466 If we do get another signal, be sure not to lose it. */
467 if (WSTOPSIG (status
) == SIGSTOP
)
469 if (stopping_threads
)
470 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
472 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
476 new_lwp
->stop_expected
= 1;
478 if (stopping_threads
)
480 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
481 new_lwp
->status_pending_p
= 1;
482 new_lwp
->status_pending
= status
;
485 /* Pass the signal on. This is what GDB does - except
486 shouldn't we really report it instead? */
487 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
490 /* Always resume the current thread. If we are stopping
491 threads, it will have a pending SIGSTOP; we may as well
493 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
497 /* Return the PC as read from the regcache of LWP, without any
501 get_pc (struct lwp_info
*lwp
)
503 struct thread_info
*saved_inferior
;
504 struct regcache
*regcache
;
507 if (the_low_target
.get_pc
== NULL
)
510 saved_inferior
= current_inferior
;
511 current_inferior
= get_lwp_thread (lwp
);
513 regcache
= get_thread_regcache (current_inferior
, 1);
514 pc
= (*the_low_target
.get_pc
) (regcache
);
517 fprintf (stderr
, "pc is 0x%lx\n", (long) pc
);
519 current_inferior
= saved_inferior
;
523 /* This function should only be called if LWP got a SIGTRAP.
524 The SIGTRAP could mean several things.
526 On i386, where decr_pc_after_break is non-zero:
527 If we were single-stepping this process using PTRACE_SINGLESTEP,
528 we will get only the one SIGTRAP (even if the instruction we
529 stepped over was a breakpoint). The value of $eip will be the
531 If we continue the process using PTRACE_CONT, we will get a
532 SIGTRAP when we hit a breakpoint. The value of $eip will be
533 the instruction after the breakpoint (i.e. needs to be
534 decremented). If we report the SIGTRAP to GDB, we must also
535 report the undecremented PC. If we cancel the SIGTRAP, we
536 must resume at the decremented PC.
538 (Presumably, not yet tested) On a non-decr_pc_after_break machine
539 with hardware or kernel single-step:
540 If we single-step over a breakpoint instruction, our PC will
541 point at the following instruction. If we continue and hit a
542 breakpoint instruction, our PC will point at the breakpoint
546 get_stop_pc (struct lwp_info
*lwp
)
550 if (the_low_target
.get_pc
== NULL
)
553 stop_pc
= get_pc (lwp
);
555 if (WSTOPSIG (lwp
->last_status
) == SIGTRAP
557 && !lwp
->stopped_by_watchpoint
558 && lwp
->last_status
>> 16 == 0)
559 stop_pc
-= the_low_target
.decr_pc_after_break
;
562 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
568 add_lwp (ptid_t ptid
)
570 struct lwp_info
*lwp
;
572 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
573 memset (lwp
, 0, sizeof (*lwp
));
577 if (the_low_target
.new_thread
!= NULL
)
578 lwp
->arch_private
= the_low_target
.new_thread ();
580 add_inferior_to_list (&all_lwps
, &lwp
->head
);
585 /* Start an inferior process and returns its pid.
586 ALLARGS is a vector of program-name and args. */
589 linux_create_inferior (char *program
, char **allargs
)
591 #ifdef HAVE_PERSONALITY
592 int personality_orig
= 0, personality_set
= 0;
594 struct lwp_info
*new_lwp
;
598 #ifdef HAVE_PERSONALITY
599 if (disable_randomization
)
602 personality_orig
= personality (0xffffffff);
603 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
606 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
608 if (errno
!= 0 || (personality_set
609 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
610 warning ("Error disabling address space randomization: %s",
615 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
621 perror_with_name ("fork");
625 ptrace (PTRACE_TRACEME
, 0, 0, 0);
627 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
628 signal (__SIGRTMIN
+ 1, SIG_DFL
);
633 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
634 stdout to stderr so that inferior i/o doesn't corrupt the connection.
635 Also, redirect stdin to /dev/null. */
636 if (remote_connection_is_stdio ())
639 open ("/dev/null", O_RDONLY
);
641 if (write (2, "stdin/stdout redirected\n",
642 sizeof ("stdin/stdout redirected\n") - 1) < 0)
643 /* Errors ignored. */;
646 execv (program
, allargs
);
648 execvp (program
, allargs
);
650 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
656 #ifdef HAVE_PERSONALITY
660 personality (personality_orig
);
662 warning ("Error restoring address space randomization: %s",
667 linux_add_process (pid
, 0);
669 ptid
= ptid_build (pid
, pid
, 0);
670 new_lwp
= add_lwp (ptid
);
671 add_thread (ptid
, new_lwp
);
672 new_lwp
->must_set_ptrace_flags
= 1;
677 /* Attach to an inferior process. */
680 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
683 struct lwp_info
*new_lwp
;
685 if (ptrace (PTRACE_ATTACH
, lwpid
, 0, 0) != 0)
687 struct buffer buffer
;
691 /* If we fail to attach to an LWP, just warn. */
692 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
693 strerror (errno
), errno
);
698 /* If we fail to attach to a process, report an error. */
699 buffer_init (&buffer
);
700 linux_ptrace_attach_warnings (lwpid
, &buffer
);
701 buffer_grow_str0 (&buffer
, "");
702 error ("%sCannot attach to lwp %ld: %s (%d)", buffer_finish (&buffer
),
703 lwpid
, strerror (errno
), errno
);
707 /* If lwp is the tgid, we handle adding existing threads later.
708 Otherwise we just add lwp without bothering about any other
710 ptid
= ptid_build (lwpid
, lwpid
, 0);
713 /* Note that extracting the pid from the current inferior is
714 safe, since we're always called in the context of the same
715 process as this new thread. */
716 int pid
= pid_of (get_thread_lwp (current_inferior
));
717 ptid
= ptid_build (pid
, lwpid
, 0);
720 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
721 add_thread (ptid
, new_lwp
);
723 /* We need to wait for SIGSTOP before being able to make the next
724 ptrace call on this LWP. */
725 new_lwp
->must_set_ptrace_flags
= 1;
727 if (linux_proc_pid_is_stopped (lwpid
))
731 "Attached to a stopped process\n");
733 /* The process is definitely stopped. It is in a job control
734 stop, unless the kernel predates the TASK_STOPPED /
735 TASK_TRACED distinction, in which case it might be in a
736 ptrace stop. Make sure it is in a ptrace stop; from there we
737 can kill it, signal it, et cetera.
739 First make sure there is a pending SIGSTOP. Since we are
740 already attached, the process can not transition from stopped
741 to running without a PTRACE_CONT; so we know this signal will
742 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
743 probably already in the queue (unless this kernel is old
744 enough to use TASK_STOPPED for ptrace stops); but since
745 SIGSTOP is not an RT signal, it can only be queued once. */
746 kill_lwp (lwpid
, SIGSTOP
);
748 /* Finally, resume the stopped process. This will deliver the
749 SIGSTOP (or a higher priority signal, just like normal
750 PTRACE_ATTACH), which we'll catch later on. */
751 ptrace (PTRACE_CONT
, lwpid
, 0, 0);
754 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
757 There are several cases to consider here:
759 1) gdbserver has already attached to the process and is being notified
760 of a new thread that is being created.
761 In this case we should ignore that SIGSTOP and resume the
762 process. This is handled below by setting stop_expected = 1,
763 and the fact that add_thread sets last_resume_kind ==
766 2) This is the first thread (the process thread), and we're attaching
767 to it via attach_inferior.
768 In this case we want the process thread to stop.
769 This is handled by having linux_attach set last_resume_kind ==
770 resume_stop after we return.
772 If the pid we are attaching to is also the tgid, we attach to and
773 stop all the existing threads. Otherwise, we attach to pid and
774 ignore any other threads in the same group as this pid.
776 3) GDB is connecting to gdbserver and is requesting an enumeration of all
778 In this case we want the thread to stop.
779 FIXME: This case is currently not properly handled.
780 We should wait for the SIGSTOP but don't. Things work apparently
781 because enough time passes between when we ptrace (ATTACH) and when
782 gdb makes the next ptrace call on the thread.
784 On the other hand, if we are currently trying to stop all threads, we
785 should treat the new thread as if we had sent it a SIGSTOP. This works
786 because we are guaranteed that the add_lwp call above added us to the
787 end of the list, and so the new thread has not yet reached
788 wait_for_sigstop (but will). */
789 new_lwp
->stop_expected
= 1;
793 linux_attach_lwp (unsigned long lwpid
)
795 linux_attach_lwp_1 (lwpid
, 0);
798 /* Attach to PID. If PID is the tgid, attach to it and all
802 linux_attach (unsigned long pid
)
804 /* Attach to PID. We will check for other threads
806 linux_attach_lwp_1 (pid
, 1);
807 linux_add_process (pid
, 1);
811 struct thread_info
*thread
;
813 /* Don't ignore the initial SIGSTOP if we just attached to this
814 process. It will be collected by wait shortly. */
815 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
816 thread
->last_resume_kind
= resume_stop
;
819 if (linux_proc_get_tgid (pid
) == pid
)
824 sprintf (pathname
, "/proc/%ld/task", pid
);
826 dir
= opendir (pathname
);
830 fprintf (stderr
, "Could not open /proc/%ld/task.\n", pid
);
835 /* At this point we attached to the tgid. Scan the task for
838 int new_threads_found
;
842 while (iterations
< 2)
844 new_threads_found
= 0;
845 /* Add all the other threads. While we go through the
846 threads, new threads may be spawned. Cycle through
847 the list of threads until we have done two iterations without
848 finding new threads. */
849 while ((dp
= readdir (dir
)) != NULL
)
852 lwp
= strtoul (dp
->d_name
, NULL
, 10);
854 /* Is this a new thread? */
856 && find_thread_ptid (ptid_build (pid
, lwp
, 0)) == NULL
)
858 linux_attach_lwp_1 (lwp
, 0);
863 Found and attached to new lwp %ld\n", lwp
);
867 if (!new_threads_found
)
888 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
890 struct counter
*counter
= args
;
892 if (ptid_get_pid (entry
->id
) == counter
->pid
)
894 if (++counter
->count
> 1)
902 last_thread_of_process_p (struct thread_info
*thread
)
904 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
905 int pid
= ptid_get_pid (ptid
);
906 struct counter counter
= { pid
, 0 };
908 return (find_inferior (&all_threads
,
909 second_thread_of_pid_p
, &counter
) == NULL
);
915 linux_kill_one_lwp (struct lwp_info
*lwp
)
917 int pid
= lwpid_of (lwp
);
919 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
920 there is no signal context, and ptrace(PTRACE_KILL) (or
921 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
922 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
923 alternative is to kill with SIGKILL. We only need one SIGKILL
924 per process, not one for each thread. But since we still support
925 linuxthreads, and we also support debugging programs using raw
926 clone without CLONE_THREAD, we send one for each thread. For
927 years, we used PTRACE_KILL only, so we're being a bit paranoid
928 about some old kernels where PTRACE_KILL might work better
929 (dubious if there are any such, but that's why it's paranoia), so
930 we try SIGKILL first, PTRACE_KILL second, and so we're fine
937 "LKL: kill (SIGKILL) %s, 0, 0 (%s)\n",
938 target_pid_to_str (ptid_of (lwp
)),
939 errno
? strerror (errno
) : "OK");
942 ptrace (PTRACE_KILL
, pid
, 0, 0);
945 "LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
946 target_pid_to_str (ptid_of (lwp
)),
947 errno
? strerror (errno
) : "OK");
950 /* Callback for `find_inferior'. Kills an lwp of a given process,
951 except the leader. */
954 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
956 struct thread_info
*thread
= (struct thread_info
*) entry
;
957 struct lwp_info
*lwp
= get_thread_lwp (thread
);
959 int pid
= * (int *) args
;
961 if (ptid_get_pid (entry
->id
) != pid
)
964 /* We avoid killing the first thread here, because of a Linux kernel (at
965 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
966 the children get a chance to be reaped, it will remain a zombie
969 if (lwpid_of (lwp
) == pid
)
972 fprintf (stderr
, "lkop: is last of process %s\n",
973 target_pid_to_str (entry
->id
));
979 linux_kill_one_lwp (lwp
);
981 /* Make sure it died. The loop is most likely unnecessary. */
982 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
983 } while (pid
> 0 && WIFSTOPPED (wstat
));
991 struct process_info
*process
;
992 struct lwp_info
*lwp
;
996 process
= find_process_pid (pid
);
1000 /* If we're killing a running inferior, make sure it is stopped
1001 first, as PTRACE_KILL will not work otherwise. */
1002 stop_all_lwps (0, NULL
);
1004 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1006 /* See the comment in linux_kill_one_lwp. We did not kill the first
1007 thread in the list, so do so now. */
1008 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1013 fprintf (stderr
, "lk_1: cannot find lwp %ld, for pid: %d\n",
1014 lwpid_of (lwp
), pid
);
1019 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
1020 lwpid_of (lwp
), pid
);
1024 linux_kill_one_lwp (lwp
);
1026 /* Make sure it died. The loop is most likely unnecessary. */
1027 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
1028 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
1031 the_target
->mourn (process
);
1033 /* Since we presently can only stop all lwps of all processes, we
1034 need to unstop lwps of other processes. */
1035 unstop_all_lwps (0, NULL
);
1039 /* Get pending signal of THREAD, for detaching purposes. This is the
1040 signal the thread last stopped for, which we need to deliver to the
1041 thread when detaching, otherwise, it'd be suppressed/lost. */
1044 get_detach_signal (struct thread_info
*thread
)
1046 enum target_signal signo
= TARGET_SIGNAL_0
;
1048 struct lwp_info
*lp
= get_thread_lwp (thread
);
1050 if (lp
->status_pending_p
)
1051 status
= lp
->status_pending
;
1054 /* If the thread had been suspended by gdbserver, and it stopped
1055 cleanly, then it'll have stopped with SIGSTOP. But we don't
1056 want to deliver that SIGSTOP. */
1057 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1058 || thread
->last_status
.value
.sig
== TARGET_SIGNAL_0
)
1061 /* Otherwise, we may need to deliver the signal we
1063 status
= lp
->last_status
;
1066 if (!WIFSTOPPED (status
))
1070 "GPS: lwp %s hasn't stopped: no pending signal\n",
1071 target_pid_to_str (ptid_of (lp
)));
1075 /* Extended wait statuses aren't real SIGTRAPs. */
1076 if (WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
1080 "GPS: lwp %s had stopped with extended "
1081 "status: no pending signal\n",
1082 target_pid_to_str (ptid_of (lp
)));
1086 signo
= target_signal_from_host (WSTOPSIG (status
));
1088 if (program_signals_p
&& !program_signals
[signo
])
1092 "GPS: lwp %s had signal %s, but it is in nopass state\n",
1093 target_pid_to_str (ptid_of (lp
)),
1094 target_signal_to_string (signo
));
1097 else if (!program_signals_p
1098 /* If we have no way to know which signals GDB does not
1099 want to have passed to the program, assume
1100 SIGTRAP/SIGINT, which is GDB's default. */
1101 && (signo
== TARGET_SIGNAL_TRAP
|| signo
== TARGET_SIGNAL_INT
))
1105 "GPS: lwp %s had signal %s, "
1106 "but we don't know if we should pass it. Default to not.\n",
1107 target_pid_to_str (ptid_of (lp
)),
1108 target_signal_to_string (signo
));
1115 "GPS: lwp %s has pending signal %s: delivering it.\n",
1116 target_pid_to_str (ptid_of (lp
)),
1117 target_signal_to_string (signo
));
1119 return WSTOPSIG (status
);
1124 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1126 struct thread_info
*thread
= (struct thread_info
*) entry
;
1127 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1128 int pid
= * (int *) args
;
1131 if (ptid_get_pid (entry
->id
) != pid
)
1134 /* If there is a pending SIGSTOP, get rid of it. */
1135 if (lwp
->stop_expected
)
1139 "Sending SIGCONT to %s\n",
1140 target_pid_to_str (ptid_of (lwp
)));
1142 kill_lwp (lwpid_of (lwp
), SIGCONT
);
1143 lwp
->stop_expected
= 0;
1146 /* Flush any pending changes to the process's registers. */
1147 regcache_invalidate_one ((struct inferior_list_entry
*)
1148 get_lwp_thread (lwp
));
1150 /* Pass on any pending signal for this thread. */
1151 sig
= get_detach_signal (thread
);
1153 /* Finally, let it resume. */
1154 if (the_low_target
.prepare_to_resume
!= NULL
)
1155 the_low_target
.prepare_to_resume (lwp
);
1156 if (ptrace (PTRACE_DETACH
, lwpid_of (lwp
), 0,
1157 (PTRACE_ARG4_TYPE
) (long) sig
) < 0)
1158 error (_("Can't detach %s: %s"),
1159 target_pid_to_str (ptid_of (lwp
)),
1167 linux_detach (int pid
)
1169 struct process_info
*process
;
1171 process
= find_process_pid (pid
);
1172 if (process
== NULL
)
1175 /* Stop all threads before detaching. First, ptrace requires that
1176 the thread is stopped to sucessfully detach. Second, thread_db
1177 may need to uninstall thread event breakpoints from memory, which
1178 only works with a stopped process anyway. */
1179 stop_all_lwps (0, NULL
);
1181 #ifdef USE_THREAD_DB
1182 thread_db_detach (process
);
1185 /* Stabilize threads (move out of jump pads). */
1186 stabilize_threads ();
1188 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1190 the_target
->mourn (process
);
1192 /* Since we presently can only stop all lwps of all processes, we
1193 need to unstop lwps of other processes. */
1194 unstop_all_lwps (0, NULL
);
1198 /* Remove all LWPs that belong to process PROC from the lwp list. */
1201 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1203 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1204 struct process_info
*process
= proc
;
1206 if (pid_of (lwp
) == pid_of (process
))
1213 linux_mourn (struct process_info
*process
)
1215 struct process_info_private
*priv
;
1217 #ifdef USE_THREAD_DB
1218 thread_db_mourn (process
);
1221 find_inferior (&all_lwps
, delete_lwp_callback
, process
);
1223 /* Freeing all private data. */
1224 priv
= process
->private;
1225 free (priv
->arch_private
);
1227 process
->private = NULL
;
1229 remove_process (process
);
1233 linux_join (int pid
)
1238 ret
= my_waitpid (pid
, &status
, 0);
1239 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1241 } while (ret
!= -1 || errno
!= ECHILD
);
1244 /* Return nonzero if the given thread is still alive. */
1246 linux_thread_alive (ptid_t ptid
)
1248 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1250 /* We assume we always know if a thread exits. If a whole process
1251 exited but we still haven't been able to report it to GDB, we'll
1252 hold on to the last lwp of the dead process. */
1259 /* Return 1 if this lwp has an interesting status pending. */
1261 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1263 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1264 ptid_t ptid
= * (ptid_t
*) arg
;
1265 struct thread_info
*thread
;
1267 /* Check if we're only interested in events from a specific process
1269 if (!ptid_equal (minus_one_ptid
, ptid
)
1270 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
1273 thread
= get_lwp_thread (lwp
);
1275 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1276 report any status pending the LWP may have. */
1277 if (thread
->last_resume_kind
== resume_stop
1278 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1281 return lwp
->status_pending_p
;
1285 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1287 ptid_t ptid
= *(ptid_t
*) data
;
1290 if (ptid_get_lwp (ptid
) != 0)
1291 lwp
= ptid_get_lwp (ptid
);
1293 lwp
= ptid_get_pid (ptid
);
1295 if (ptid_get_lwp (entry
->id
) == lwp
)
1302 find_lwp_pid (ptid_t ptid
)
1304 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
1307 static struct lwp_info
*
1308 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
1311 int to_wait_for
= -1;
1312 struct lwp_info
*child
= NULL
;
1315 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1317 if (ptid_equal (ptid
, minus_one_ptid
))
1318 to_wait_for
= -1; /* any child */
1320 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1326 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1327 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1330 perror_with_name ("waitpid");
1333 && (!WIFSTOPPED (*wstatp
)
1334 || (WSTOPSIG (*wstatp
) != 32
1335 && WSTOPSIG (*wstatp
) != 33)))
1336 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1338 child
= find_lwp_pid (pid_to_ptid (ret
));
1340 /* If we didn't find a process, one of two things presumably happened:
1341 - A process we started and then detached from has exited. Ignore it.
1342 - A process we are controlling has forked and the new child's stop
1343 was reported to us by the kernel. Save its PID. */
1344 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1346 add_to_pid_list (&stopped_pids
, ret
, *wstatp
);
1349 else if (child
== NULL
)
1354 child
->last_status
= *wstatp
;
1356 /* Architecture-specific setup after inferior is running.
1357 This needs to happen after we have attached to the inferior
1358 and it is stopped for the first time, but before we access
1359 any inferior registers. */
1362 the_low_target
.arch_setup ();
1363 #ifdef HAVE_LINUX_REGSETS
1364 memset (disabled_regsets
, 0, num_regsets
);
1369 /* Fetch the possibly triggered data watchpoint info and store it in
1372 On some archs, like x86, that use debug registers to set
1373 watchpoints, it's possible that the way to know which watched
1374 address trapped, is to check the register that is used to select
1375 which address to watch. Problem is, between setting the
1376 watchpoint and reading back which data address trapped, the user
1377 may change the set of watchpoints, and, as a consequence, GDB
1378 changes the debug registers in the inferior. To avoid reading
1379 back a stale stopped-data-address when that happens, we cache in
1380 LP the fact that a watchpoint trapped, and the corresponding data
1381 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1382 changes the debug registers meanwhile, we have the cached data we
1385 if (WIFSTOPPED (*wstatp
) && WSTOPSIG (*wstatp
) == SIGTRAP
)
1387 if (the_low_target
.stopped_by_watchpoint
== NULL
)
1389 child
->stopped_by_watchpoint
= 0;
1393 struct thread_info
*saved_inferior
;
1395 saved_inferior
= current_inferior
;
1396 current_inferior
= get_lwp_thread (child
);
1398 child
->stopped_by_watchpoint
1399 = the_low_target
.stopped_by_watchpoint ();
1401 if (child
->stopped_by_watchpoint
)
1403 if (the_low_target
.stopped_data_address
!= NULL
)
1404 child
->stopped_data_address
1405 = the_low_target
.stopped_data_address ();
1407 child
->stopped_data_address
= 0;
1410 current_inferior
= saved_inferior
;
1414 /* Store the STOP_PC, with adjustment applied. This depends on the
1415 architecture being defined already (so that CHILD has a valid
1416 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1418 if (WIFSTOPPED (*wstatp
))
1419 child
->stop_pc
= get_stop_pc (child
);
1422 && WIFSTOPPED (*wstatp
)
1423 && the_low_target
.get_pc
!= NULL
)
1425 struct thread_info
*saved_inferior
= current_inferior
;
1426 struct regcache
*regcache
;
1429 current_inferior
= get_lwp_thread (child
);
1430 regcache
= get_thread_regcache (current_inferior
, 1);
1431 pc
= (*the_low_target
.get_pc
) (regcache
);
1432 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1433 current_inferior
= saved_inferior
;
1439 /* This function should only be called if the LWP got a SIGTRAP.
1441 Handle any tracepoint steps or hits. Return true if a tracepoint
1442 event was handled, 0 otherwise. */
1445 handle_tracepoints (struct lwp_info
*lwp
)
1447 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1448 int tpoint_related_event
= 0;
1450 /* If this tracepoint hit causes a tracing stop, we'll immediately
1451 uninsert tracepoints. To do this, we temporarily pause all
1452 threads, unpatch away, and then unpause threads. We need to make
1453 sure the unpausing doesn't resume LWP too. */
1456 /* And we need to be sure that any all-threads-stopping doesn't try
1457 to move threads out of the jump pads, as it could deadlock the
1458 inferior (LWP could be in the jump pad, maybe even holding the
1461 /* Do any necessary step collect actions. */
1462 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1464 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1466 /* See if we just hit a tracepoint and do its main collect
1468 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1472 gdb_assert (lwp
->suspended
== 0);
1473 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1475 if (tpoint_related_event
)
1478 fprintf (stderr
, "got a tracepoint event\n");
1485 /* Convenience wrapper. Returns true if LWP is presently collecting a
1489 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1490 struct fast_tpoint_collect_status
*status
)
1492 CORE_ADDR thread_area
;
1494 if (the_low_target
.get_thread_area
== NULL
)
1497 /* Get the thread area address. This is used to recognize which
1498 thread is which when tracing with the in-process agent library.
1499 We don't read anything from the address, and treat it as opaque;
1500 it's the address itself that we assume is unique per-thread. */
1501 if ((*the_low_target
.get_thread_area
) (lwpid_of (lwp
), &thread_area
) == -1)
1504 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1507 /* The reason we resume in the caller, is because we want to be able
1508 to pass lwp->status_pending as WSTAT, and we need to clear
1509 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1510 refuses to resume. */
1513 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1515 struct thread_info
*saved_inferior
;
1517 saved_inferior
= current_inferior
;
1518 current_inferior
= get_lwp_thread (lwp
);
1521 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1522 && supports_fast_tracepoints ()
1523 && agent_loaded_p ())
1525 struct fast_tpoint_collect_status status
;
1530 Checking whether LWP %ld needs to move out of the jump pad.\n",
1533 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1536 || (WSTOPSIG (*wstat
) != SIGILL
1537 && WSTOPSIG (*wstat
) != SIGFPE
1538 && WSTOPSIG (*wstat
) != SIGSEGV
1539 && WSTOPSIG (*wstat
) != SIGBUS
))
1541 lwp
->collecting_fast_tracepoint
= r
;
1545 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1547 /* Haven't executed the original instruction yet.
1548 Set breakpoint there, and wait till it's hit,
1549 then single-step until exiting the jump pad. */
1550 lwp
->exit_jump_pad_bkpt
1551 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1556 Checking whether LWP %ld needs to move out of the jump pad...it does\n",
1558 current_inferior
= saved_inferior
;
1565 /* If we get a synchronous signal while collecting, *and*
1566 while executing the (relocated) original instruction,
1567 reset the PC to point at the tpoint address, before
1568 reporting to GDB. Otherwise, it's an IPA lib bug: just
1569 report the signal to GDB, and pray for the best. */
1571 lwp
->collecting_fast_tracepoint
= 0;
1574 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1575 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1578 struct regcache
*regcache
;
1580 /* The si_addr on a few signals references the address
1581 of the faulting instruction. Adjust that as
1583 if ((WSTOPSIG (*wstat
) == SIGILL
1584 || WSTOPSIG (*wstat
) == SIGFPE
1585 || WSTOPSIG (*wstat
) == SIGBUS
1586 || WSTOPSIG (*wstat
) == SIGSEGV
)
1587 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &info
) == 0
1588 /* Final check just to make sure we don't clobber
1589 the siginfo of non-kernel-sent signals. */
1590 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1592 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1593 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &info
);
1596 regcache
= get_thread_regcache (get_lwp_thread (lwp
), 1);
1597 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1598 lwp
->stop_pc
= status
.tpoint_addr
;
1600 /* Cancel any fast tracepoint lock this thread was
1602 force_unlock_trace_buffer ();
1605 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1609 "Cancelling fast exit-jump-pad: removing bkpt. "
1610 "stopping all threads momentarily.\n");
1612 stop_all_lwps (1, lwp
);
1613 cancel_breakpoints ();
1615 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1616 lwp
->exit_jump_pad_bkpt
= NULL
;
1618 unstop_all_lwps (1, lwp
);
1620 gdb_assert (lwp
->suspended
>= 0);
1627 Checking whether LWP %ld needs to move out of the jump pad...no\n",
1630 current_inferior
= saved_inferior
;
1634 /* Enqueue one signal in the "signals to report later when out of the
1638 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1640 struct pending_signals
*p_sig
;
1644 Deferring signal %d for LWP %ld.\n", WSTOPSIG (*wstat
), lwpid_of (lwp
));
1648 struct pending_signals
*sig
;
1650 for (sig
= lwp
->pending_signals_to_report
;
1654 " Already queued %d\n",
1657 fprintf (stderr
, " (no more currently queued signals)\n");
1660 /* Don't enqueue non-RT signals if they are already in the deferred
1661 queue. (SIGSTOP being the easiest signal to see ending up here
1663 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1665 struct pending_signals
*sig
;
1667 for (sig
= lwp
->pending_signals_to_report
;
1671 if (sig
->signal
== WSTOPSIG (*wstat
))
1675 "Not requeuing already queued non-RT signal %d"
1684 p_sig
= xmalloc (sizeof (*p_sig
));
1685 p_sig
->prev
= lwp
->pending_signals_to_report
;
1686 p_sig
->signal
= WSTOPSIG (*wstat
);
1687 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1688 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
1690 lwp
->pending_signals_to_report
= p_sig
;
1693 /* Dequeue one signal from the "signals to report later when out of
1694 the jump pad" list. */
1697 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1699 if (lwp
->pending_signals_to_report
!= NULL
)
1701 struct pending_signals
**p_sig
;
1703 p_sig
= &lwp
->pending_signals_to_report
;
1704 while ((*p_sig
)->prev
!= NULL
)
1705 p_sig
= &(*p_sig
)->prev
;
1707 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1708 if ((*p_sig
)->info
.si_signo
!= 0)
1709 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
1714 fprintf (stderr
, "Reporting deferred signal %d for LWP %ld.\n",
1715 WSTOPSIG (*wstat
), lwpid_of (lwp
));
1719 struct pending_signals
*sig
;
1721 for (sig
= lwp
->pending_signals_to_report
;
1725 " Still queued %d\n",
1728 fprintf (stderr
, " (no more queued signals)\n");
1737 /* Arrange for a breakpoint to be hit again later. We don't keep the
1738 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1739 will handle the current event, eventually we will resume this LWP,
1740 and this breakpoint will trap again. */
1743 cancel_breakpoint (struct lwp_info
*lwp
)
1745 struct thread_info
*saved_inferior
;
1747 /* There's nothing to do if we don't support breakpoints. */
1748 if (!supports_breakpoints ())
1751 /* breakpoint_at reads from current inferior. */
1752 saved_inferior
= current_inferior
;
1753 current_inferior
= get_lwp_thread (lwp
);
1755 if ((*the_low_target
.breakpoint_at
) (lwp
->stop_pc
))
1759 "CB: Push back breakpoint for %s\n",
1760 target_pid_to_str (ptid_of (lwp
)));
1762 /* Back up the PC if necessary. */
1763 if (the_low_target
.decr_pc_after_break
)
1765 struct regcache
*regcache
1766 = get_thread_regcache (current_inferior
, 1);
1767 (*the_low_target
.set_pc
) (regcache
, lwp
->stop_pc
);
1770 current_inferior
= saved_inferior
;
1777 "CB: No breakpoint found at %s for [%s]\n",
1778 paddress (lwp
->stop_pc
),
1779 target_pid_to_str (ptid_of (lwp
)));
1782 current_inferior
= saved_inferior
;
1786 /* When the event-loop is doing a step-over, this points at the thread
1788 ptid_t step_over_bkpt
;
1790 /* Wait for an event from child PID. If PID is -1, wait for any
1791 child. Store the stop status through the status pointer WSTAT.
1792 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1793 event was found and OPTIONS contains WNOHANG. Return the PID of
1794 the stopped child otherwise. */
1797 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1799 struct lwp_info
*event_child
, *requested_child
;
1803 requested_child
= NULL
;
1805 /* Check for a lwp with a pending status. */
1807 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
1809 event_child
= (struct lwp_info
*)
1810 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1811 if (debug_threads
&& event_child
)
1812 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1816 requested_child
= find_lwp_pid (ptid
);
1818 if (!stopping_threads
1819 && requested_child
->status_pending_p
1820 && requested_child
->collecting_fast_tracepoint
)
1822 enqueue_one_deferred_signal (requested_child
,
1823 &requested_child
->status_pending
);
1824 requested_child
->status_pending_p
= 0;
1825 requested_child
->status_pending
= 0;
1826 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
1829 if (requested_child
->suspended
1830 && requested_child
->status_pending_p
)
1831 fatal ("requesting an event out of a suspended child?");
1833 if (requested_child
->status_pending_p
)
1834 event_child
= requested_child
;
1837 if (event_child
!= NULL
)
1840 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1841 lwpid_of (event_child
), event_child
->status_pending
);
1842 *wstat
= event_child
->status_pending
;
1843 event_child
->status_pending_p
= 0;
1844 event_child
->status_pending
= 0;
1845 current_inferior
= get_lwp_thread (event_child
);
1846 return lwpid_of (event_child
);
1849 if (ptid_is_pid (ptid
))
1851 /* A request to wait for a specific tgid. This is not possible
1852 with waitpid, so instead, we wait for any child, and leave
1853 children we're not interested in right now with a pending
1854 status to report later. */
1855 wait_ptid
= minus_one_ptid
;
1860 /* We only enter this loop if no process has a pending wait status. Thus
1861 any action taken in response to a wait status inside this loop is
1862 responding as soon as we detect the status, not after any pending
1866 event_child
= linux_wait_for_lwp (wait_ptid
, wstat
, options
);
1868 if ((options
& WNOHANG
) && event_child
== NULL
)
1871 fprintf (stderr
, "WNOHANG set, no event found\n");
1875 if (event_child
== NULL
)
1876 error ("event from unknown child");
1878 if (ptid_is_pid (ptid
)
1879 && ptid_get_pid (ptid
) != ptid_get_pid (ptid_of (event_child
)))
1881 if (! WIFSTOPPED (*wstat
))
1882 mark_lwp_dead (event_child
, *wstat
);
1885 event_child
->status_pending_p
= 1;
1886 event_child
->status_pending
= *wstat
;
1891 current_inferior
= get_lwp_thread (event_child
);
1893 /* Check for thread exit. */
1894 if (! WIFSTOPPED (*wstat
))
1897 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1899 /* If the last thread is exiting, just return. */
1900 if (last_thread_of_process_p (current_inferior
))
1903 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1904 lwpid_of (event_child
));
1905 return lwpid_of (event_child
);
1910 current_inferior
= (struct thread_info
*) all_threads
.head
;
1912 fprintf (stderr
, "Current inferior is now %ld\n",
1913 lwpid_of (get_thread_lwp (current_inferior
)));
1917 current_inferior
= NULL
;
1919 fprintf (stderr
, "Current inferior is now <NULL>\n");
1922 /* If we were waiting for this particular child to do something...
1923 well, it did something. */
1924 if (requested_child
!= NULL
)
1926 int lwpid
= lwpid_of (event_child
);
1928 /* Cancel the step-over operation --- the thread that
1929 started it is gone. */
1930 if (finish_step_over (event_child
))
1931 unstop_all_lwps (1, event_child
);
1932 delete_lwp (event_child
);
1936 delete_lwp (event_child
);
1938 /* Wait for a more interesting event. */
1942 if (event_child
->must_set_ptrace_flags
)
1944 linux_enable_event_reporting (lwpid_of (event_child
));
1945 event_child
->must_set_ptrace_flags
= 0;
1948 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1949 && *wstat
>> 16 != 0)
1951 handle_extended_wait (event_child
, *wstat
);
1955 if (WIFSTOPPED (*wstat
)
1956 && WSTOPSIG (*wstat
) == SIGSTOP
1957 && event_child
->stop_expected
)
1962 fprintf (stderr
, "Expected stop.\n");
1963 event_child
->stop_expected
= 0;
1965 should_stop
= (current_inferior
->last_resume_kind
== resume_stop
1966 || stopping_threads
);
1970 linux_resume_one_lwp (event_child
,
1971 event_child
->stepping
, 0, NULL
);
1976 return lwpid_of (event_child
);
1983 /* Count the LWP's that have had events. */
1986 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
1988 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1989 struct thread_info
*thread
= get_lwp_thread (lp
);
1992 gdb_assert (count
!= NULL
);
1994 /* Count only resumed LWPs that have a SIGTRAP event pending that
1995 should be reported to GDB. */
1996 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1997 && thread
->last_resume_kind
!= resume_stop
1998 && lp
->status_pending_p
1999 && WIFSTOPPED (lp
->status_pending
)
2000 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2001 && !breakpoint_inserted_here (lp
->stop_pc
))
2007 /* Select the LWP (if any) that is currently being single-stepped. */
2010 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2012 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2013 struct thread_info
*thread
= get_lwp_thread (lp
);
2015 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2016 && thread
->last_resume_kind
== resume_step
2017 && lp
->status_pending_p
)
2023 /* Select the Nth LWP that has had a SIGTRAP event that should be
2027 select_event_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
);
2031 int *selector
= data
;
2033 gdb_assert (selector
!= NULL
);
2035 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2036 if (thread
->last_resume_kind
!= resume_stop
2037 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2038 && lp
->status_pending_p
2039 && WIFSTOPPED (lp
->status_pending
)
2040 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2041 && !breakpoint_inserted_here (lp
->stop_pc
))
2042 if ((*selector
)-- == 0)
2049 cancel_breakpoints_callback (struct inferior_list_entry
*entry
, void *data
)
2051 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2052 struct thread_info
*thread
= get_lwp_thread (lp
);
2053 struct lwp_info
*event_lp
= data
;
2055 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
2059 /* If a LWP other than the LWP that we're reporting an event for has
2060 hit a GDB breakpoint (as opposed to some random trap signal),
2061 then just arrange for it to hit it again later. We don't keep
2062 the SIGTRAP status and don't forward the SIGTRAP signal to the
2063 LWP. We will handle the current event, eventually we will resume
2064 all LWPs, and this one will get its breakpoint trap again.
2066 If we do not do this, then we run the risk that the user will
2067 delete or disable the breakpoint, but the LWP will have already
2070 if (thread
->last_resume_kind
!= resume_stop
2071 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2072 && lp
->status_pending_p
2073 && WIFSTOPPED (lp
->status_pending
)
2074 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2076 && !lp
->stopped_by_watchpoint
2077 && cancel_breakpoint (lp
))
2078 /* Throw away the SIGTRAP. */
2079 lp
->status_pending_p
= 0;
2085 linux_cancel_breakpoints (void)
2087 find_inferior (&all_lwps
, cancel_breakpoints_callback
, NULL
);
2090 /* Select one LWP out of those that have events pending. */
2093 select_event_lwp (struct lwp_info
**orig_lp
)
2096 int random_selector
;
2097 struct lwp_info
*event_lp
;
2099 /* Give preference to any LWP that is being single-stepped. */
2101 = (struct lwp_info
*) find_inferior (&all_lwps
,
2102 select_singlestep_lwp_callback
, NULL
);
2103 if (event_lp
!= NULL
)
2107 "SEL: Select single-step %s\n",
2108 target_pid_to_str (ptid_of (event_lp
)));
2112 /* No single-stepping LWP. Select one at random, out of those
2113 which have had SIGTRAP events. */
2115 /* First see how many SIGTRAP events we have. */
2116 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
2118 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
2119 random_selector
= (int)
2120 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2122 if (debug_threads
&& num_events
> 1)
2124 "SEL: Found %d SIGTRAP events, selecting #%d\n",
2125 num_events
, random_selector
);
2127 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
2128 select_event_lwp_callback
,
2132 if (event_lp
!= NULL
)
2134 /* Switch the event LWP. */
2135 *orig_lp
= event_lp
;
2139 /* Decrement the suspend count of an LWP. */
2142 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2144 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2146 /* Ignore EXCEPT. */
2152 gdb_assert (lwp
->suspended
>= 0);
2156 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2160 unsuspend_all_lwps (struct lwp_info
*except
)
2162 find_inferior (&all_lwps
, unsuspend_one_lwp
, except
);
2165 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2166 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2168 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2169 static ptid_t
linux_wait_1 (ptid_t ptid
,
2170 struct target_waitstatus
*ourstatus
,
2171 int target_options
);
2173 /* Stabilize threads (move out of jump pads).
2175 If a thread is midway collecting a fast tracepoint, we need to
2176 finish the collection and move it out of the jump pad before
2177 reporting the signal.
2179 This avoids recursion while collecting (when a signal arrives
2180 midway, and the signal handler itself collects), which would trash
2181 the trace buffer. In case the user set a breakpoint in a signal
2182 handler, this avoids the backtrace showing the jump pad, etc..
2183 Most importantly, there are certain things we can't do safely if
2184 threads are stopped in a jump pad (or in its callee's). For
2187 - starting a new trace run. A thread still collecting the
2188 previous run, could trash the trace buffer when resumed. The trace
2189 buffer control structures would have been reset but the thread had
2190 no way to tell. The thread could even midway memcpy'ing to the
2191 buffer, which would mean that when resumed, it would clobber the
2192 trace buffer that had been set for a new run.
2194 - we can't rewrite/reuse the jump pads for new tracepoints
2195 safely. Say you do tstart while a thread is stopped midway while
2196 collecting. When the thread is later resumed, it finishes the
2197 collection, and returns to the jump pad, to execute the original
2198 instruction that was under the tracepoint jump at the time the
2199 older run had been started. If the jump pad had been rewritten
2200 since for something else in the new run, the thread would now
2201 execute the wrong / random instructions. */
2204 linux_stabilize_threads (void)
2206 struct thread_info
*save_inferior
;
2207 struct lwp_info
*lwp_stuck
;
2210 = (struct lwp_info
*) find_inferior (&all_lwps
,
2211 stuck_in_jump_pad_callback
, NULL
);
2212 if (lwp_stuck
!= NULL
)
2215 fprintf (stderr
, "can't stabilize, LWP %ld is stuck in jump pad\n",
2216 lwpid_of (lwp_stuck
));
2220 save_inferior
= current_inferior
;
2222 stabilizing_threads
= 1;
2225 for_each_inferior (&all_lwps
, move_out_of_jump_pad_callback
);
2227 /* Loop until all are stopped out of the jump pads. */
2228 while (find_inferior (&all_lwps
, lwp_running
, NULL
) != NULL
)
2230 struct target_waitstatus ourstatus
;
2231 struct lwp_info
*lwp
;
2234 /* Note that we go through the full wait even loop. While
2235 moving threads out of jump pad, we need to be able to step
2236 over internal breakpoints and such. */
2237 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2239 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2241 lwp
= get_thread_lwp (current_inferior
);
2246 if (ourstatus
.value
.sig
!= TARGET_SIGNAL_0
2247 || current_inferior
->last_resume_kind
== resume_stop
)
2249 wstat
= W_STOPCODE (target_signal_to_host (ourstatus
.value
.sig
));
2250 enqueue_one_deferred_signal (lwp
, &wstat
);
2255 find_inferior (&all_lwps
, unsuspend_one_lwp
, NULL
);
2257 stabilizing_threads
= 0;
2259 current_inferior
= save_inferior
;
2264 = (struct lwp_info
*) find_inferior (&all_lwps
,
2265 stuck_in_jump_pad_callback
, NULL
);
2266 if (lwp_stuck
!= NULL
)
2267 fprintf (stderr
, "couldn't stabilize, LWP %ld got stuck in jump pad\n",
2268 lwpid_of (lwp_stuck
));
2272 /* Wait for process, returns status. */
2275 linux_wait_1 (ptid_t ptid
,
2276 struct target_waitstatus
*ourstatus
, int target_options
)
2279 struct lwp_info
*event_child
;
2282 int step_over_finished
;
2283 int bp_explains_trap
;
2284 int maybe_internal_trap
;
2288 /* Translate generic target options into linux options. */
2290 if (target_options
& TARGET_WNOHANG
)
2294 bp_explains_trap
= 0;
2296 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2298 /* If we were only supposed to resume one thread, only wait for
2299 that thread - if it's still alive. If it died, however - which
2300 can happen if we're coming from the thread death case below -
2301 then we need to make sure we restart the other threads. We could
2302 pick a thread at random or restart all; restarting all is less
2305 && !ptid_equal (cont_thread
, null_ptid
)
2306 && !ptid_equal (cont_thread
, minus_one_ptid
))
2308 struct thread_info
*thread
;
2310 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
2313 /* No stepping, no signal - unless one is pending already, of course. */
2316 struct thread_resume resume_info
;
2317 resume_info
.thread
= minus_one_ptid
;
2318 resume_info
.kind
= resume_continue
;
2319 resume_info
.sig
= 0;
2320 linux_resume (&resume_info
, 1);
2326 if (ptid_equal (step_over_bkpt
, null_ptid
))
2327 pid
= linux_wait_for_event (ptid
, &w
, options
);
2331 fprintf (stderr
, "step_over_bkpt set [%s], doing a blocking wait\n",
2332 target_pid_to_str (step_over_bkpt
));
2333 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2336 if (pid
== 0) /* only if TARGET_WNOHANG */
2339 event_child
= get_thread_lwp (current_inferior
);
2341 /* If we are waiting for a particular child, and it exited,
2342 linux_wait_for_event will return its exit status. Similarly if
2343 the last child exited. If this is not the last child, however,
2344 do not report it as exited until there is a 'thread exited' response
2345 available in the remote protocol. Instead, just wait for another event.
2346 This should be safe, because if the thread crashed we will already
2347 have reported the termination signal to GDB; that should stop any
2348 in-progress stepping operations, etc.
2350 Report the exit status of the last thread to exit. This matches
2351 LinuxThreads' behavior. */
2353 if (last_thread_of_process_p (current_inferior
))
2355 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2359 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2360 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2364 "\nChild exited with retcode = %x \n",
2369 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2370 ourstatus
->value
.sig
= target_signal_from_host (WTERMSIG (w
));
2374 "\nChild terminated with signal = %x \n",
2379 return ptid_of (event_child
);
2384 if (!WIFSTOPPED (w
))
2388 /* If this event was not handled before, and is not a SIGTRAP, we
2389 report it. SIGILL and SIGSEGV are also treated as traps in case
2390 a breakpoint is inserted at the current PC. If this target does
2391 not support internal breakpoints at all, we also report the
2392 SIGTRAP without further processing; it's of no concern to us. */
2394 = (supports_breakpoints ()
2395 && (WSTOPSIG (w
) == SIGTRAP
2396 || ((WSTOPSIG (w
) == SIGILL
2397 || WSTOPSIG (w
) == SIGSEGV
)
2398 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2400 if (maybe_internal_trap
)
2402 /* Handle anything that requires bookkeeping before deciding to
2403 report the event or continue waiting. */
2405 /* First check if we can explain the SIGTRAP with an internal
2406 breakpoint, or if we should possibly report the event to GDB.
2407 Do this before anything that may remove or insert a
2409 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2411 /* We have a SIGTRAP, possibly a step-over dance has just
2412 finished. If so, tweak the state machine accordingly,
2413 reinsert breakpoints and delete any reinsert (software
2414 single-step) breakpoints. */
2415 step_over_finished
= finish_step_over (event_child
);
2417 /* Now invoke the callbacks of any internal breakpoints there. */
2418 check_breakpoints (event_child
->stop_pc
);
2420 /* Handle tracepoint data collecting. This may overflow the
2421 trace buffer, and cause a tracing stop, removing
2423 trace_event
= handle_tracepoints (event_child
);
2425 if (bp_explains_trap
)
2427 /* If we stepped or ran into an internal breakpoint, we've
2428 already handled it. So next time we resume (from this
2429 PC), we should step over it. */
2431 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2433 if (breakpoint_here (event_child
->stop_pc
))
2434 event_child
->need_step_over
= 1;
2439 /* We have some other signal, possibly a step-over dance was in
2440 progress, and it should be cancelled too. */
2441 step_over_finished
= finish_step_over (event_child
);
2444 /* We have all the data we need. Either report the event to GDB, or
2445 resume threads and keep waiting for more. */
2447 /* If we're collecting a fast tracepoint, finish the collection and
2448 move out of the jump pad before delivering a signal. See
2449 linux_stabilize_threads. */
2452 && WSTOPSIG (w
) != SIGTRAP
2453 && supports_fast_tracepoints ()
2454 && agent_loaded_p ())
2458 "Got signal %d for LWP %ld. Check if we need "
2459 "to defer or adjust it.\n",
2460 WSTOPSIG (w
), lwpid_of (event_child
));
2462 /* Allow debugging the jump pad itself. */
2463 if (current_inferior
->last_resume_kind
!= resume_step
2464 && maybe_move_out_of_jump_pad (event_child
, &w
))
2466 enqueue_one_deferred_signal (event_child
, &w
);
2470 "Signal %d for LWP %ld deferred (in jump pad)\n",
2471 WSTOPSIG (w
), lwpid_of (event_child
));
2473 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2478 if (event_child
->collecting_fast_tracepoint
)
2482 LWP %ld was trying to move out of the jump pad (%d). \
2483 Check if we're already there.\n",
2484 lwpid_of (event_child
),
2485 event_child
->collecting_fast_tracepoint
);
2489 event_child
->collecting_fast_tracepoint
2490 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2492 if (event_child
->collecting_fast_tracepoint
!= 1)
2494 /* No longer need this breakpoint. */
2495 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2499 "No longer need exit-jump-pad bkpt; removing it."
2500 "stopping all threads momentarily.\n");
2502 /* Other running threads could hit this breakpoint.
2503 We don't handle moribund locations like GDB does,
2504 instead we always pause all threads when removing
2505 breakpoints, so that any step-over or
2506 decr_pc_after_break adjustment is always taken
2507 care of while the breakpoint is still
2509 stop_all_lwps (1, event_child
);
2510 cancel_breakpoints ();
2512 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2513 event_child
->exit_jump_pad_bkpt
= NULL
;
2515 unstop_all_lwps (1, event_child
);
2517 gdb_assert (event_child
->suspended
>= 0);
2521 if (event_child
->collecting_fast_tracepoint
== 0)
2525 "fast tracepoint finished "
2526 "collecting successfully.\n");
2528 /* We may have a deferred signal to report. */
2529 if (dequeue_one_deferred_signal (event_child
, &w
))
2532 fprintf (stderr
, "dequeued one signal.\n");
2537 fprintf (stderr
, "no deferred signals.\n");
2539 if (stabilizing_threads
)
2541 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2542 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2543 return ptid_of (event_child
);
2549 /* Check whether GDB would be interested in this event. */
2551 /* If GDB is not interested in this signal, don't stop other
2552 threads, and don't report it to GDB. Just resume the inferior
2553 right away. We do this for threading-related signals as well as
2554 any that GDB specifically requested we ignore. But never ignore
2555 SIGSTOP if we sent it ourselves, and do not ignore signals when
2556 stepping - they may require special handling to skip the signal
2558 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2561 && current_inferior
->last_resume_kind
!= resume_step
2563 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2564 (current_process ()->private->thread_db
!= NULL
2565 && (WSTOPSIG (w
) == __SIGRTMIN
2566 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2569 (pass_signals
[target_signal_from_host (WSTOPSIG (w
))]
2570 && !(WSTOPSIG (w
) == SIGSTOP
2571 && current_inferior
->last_resume_kind
== resume_stop
))))
2573 siginfo_t info
, *info_p
;
2576 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
2577 WSTOPSIG (w
), lwpid_of (event_child
));
2579 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
), 0, &info
) == 0)
2583 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2584 WSTOPSIG (w
), info_p
);
2588 /* If GDB wanted this thread to single step, we always want to
2589 report the SIGTRAP, and let GDB handle it. Watchpoints should
2590 always be reported. So should signals we can't explain. A
2591 SIGTRAP we can't explain could be a GDB breakpoint --- we may or
2592 not support Z0 breakpoints. If we do, we're be able to handle
2593 GDB breakpoints on top of internal breakpoints, by handling the
2594 internal breakpoint and still reporting the event to GDB. If we
2595 don't, we're out of luck, GDB won't see the breakpoint hit. */
2596 report_to_gdb
= (!maybe_internal_trap
2597 || current_inferior
->last_resume_kind
== resume_step
2598 || event_child
->stopped_by_watchpoint
2599 || (!step_over_finished
2600 && !bp_explains_trap
&& !trace_event
)
2601 || (gdb_breakpoint_here (event_child
->stop_pc
)
2602 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)));
2604 /* We found no reason GDB would want us to stop. We either hit one
2605 of our own breakpoints, or finished an internal step GDB
2606 shouldn't know about. */
2611 if (bp_explains_trap
)
2612 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2613 if (step_over_finished
)
2614 fprintf (stderr
, "Step-over finished.\n");
2616 fprintf (stderr
, "Tracepoint event.\n");
2619 /* We're not reporting this breakpoint to GDB, so apply the
2620 decr_pc_after_break adjustment to the inferior's regcache
2623 if (the_low_target
.set_pc
!= NULL
)
2625 struct regcache
*regcache
2626 = get_thread_regcache (get_lwp_thread (event_child
), 1);
2627 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2630 /* We may have finished stepping over a breakpoint. If so,
2631 we've stopped and suspended all LWPs momentarily except the
2632 stepping one. This is where we resume them all again. We're
2633 going to keep waiting, so use proceed, which handles stepping
2634 over the next breakpoint. */
2636 fprintf (stderr
, "proceeding all threads.\n");
2638 if (step_over_finished
)
2639 unsuspend_all_lwps (event_child
);
2641 proceed_all_lwps ();
2647 if (current_inferior
->last_resume_kind
== resume_step
)
2648 fprintf (stderr
, "GDB wanted to single-step, reporting event.\n");
2649 if (event_child
->stopped_by_watchpoint
)
2650 fprintf (stderr
, "Stopped by watchpoint.\n");
2651 if (gdb_breakpoint_here (event_child
->stop_pc
))
2652 fprintf (stderr
, "Stopped by GDB breakpoint.\n");
2654 fprintf (stderr
, "Hit a non-gdbserver trap event.\n");
2657 /* Alright, we're going to report a stop. */
2659 if (!non_stop
&& !stabilizing_threads
)
2661 /* In all-stop, stop all threads. */
2662 stop_all_lwps (0, NULL
);
2664 /* If we're not waiting for a specific LWP, choose an event LWP
2665 from among those that have had events. Giving equal priority
2666 to all LWPs that have had events helps prevent
2668 if (ptid_equal (ptid
, minus_one_ptid
))
2670 event_child
->status_pending_p
= 1;
2671 event_child
->status_pending
= w
;
2673 select_event_lwp (&event_child
);
2675 event_child
->status_pending_p
= 0;
2676 w
= event_child
->status_pending
;
2679 /* Now that we've selected our final event LWP, cancel any
2680 breakpoints in other LWPs that have hit a GDB breakpoint.
2681 See the comment in cancel_breakpoints_callback to find out
2683 find_inferior (&all_lwps
, cancel_breakpoints_callback
, event_child
);
2685 /* If we were going a step-over, all other threads but the stepping one
2686 had been paused in start_step_over, with their suspend counts
2687 incremented. We don't want to do a full unstop/unpause, because we're
2688 in all-stop mode (so we want threads stopped), but we still need to
2689 unsuspend the other threads, to decrement their `suspended' count
2691 if (step_over_finished
)
2692 unsuspend_all_lwps (event_child
);
2694 /* Stabilize threads (move out of jump pads). */
2695 stabilize_threads ();
2699 /* If we just finished a step-over, then all threads had been
2700 momentarily paused. In all-stop, that's fine, we want
2701 threads stopped by now anyway. In non-stop, we need to
2702 re-resume threads that GDB wanted to be running. */
2703 if (step_over_finished
)
2704 unstop_all_lwps (1, event_child
);
2707 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2709 if (current_inferior
->last_resume_kind
== resume_stop
2710 && WSTOPSIG (w
) == SIGSTOP
)
2712 /* A thread that has been requested to stop by GDB with vCont;t,
2713 and it stopped cleanly, so report as SIG0. The use of
2714 SIGSTOP is an implementation detail. */
2715 ourstatus
->value
.sig
= TARGET_SIGNAL_0
;
2717 else if (current_inferior
->last_resume_kind
== resume_stop
2718 && WSTOPSIG (w
) != SIGSTOP
)
2720 /* A thread that has been requested to stop by GDB with vCont;t,
2721 but, it stopped for other reasons. */
2722 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2726 ourstatus
->value
.sig
= target_signal_from_host (WSTOPSIG (w
));
2729 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
2732 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
2733 target_pid_to_str (ptid_of (event_child
)),
2735 ourstatus
->value
.sig
);
2737 return ptid_of (event_child
);
2740 /* Get rid of any pending event in the pipe. */
2742 async_file_flush (void)
2748 ret
= read (linux_event_pipe
[0], &buf
, 1);
2749 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
2752 /* Put something in the pipe, so the event loop wakes up. */
2754 async_file_mark (void)
2758 async_file_flush ();
2761 ret
= write (linux_event_pipe
[1], "+", 1);
2762 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
2764 /* Ignore EAGAIN. If the pipe is full, the event loop will already
2765 be awakened anyway. */
2769 linux_wait (ptid_t ptid
,
2770 struct target_waitstatus
*ourstatus
, int target_options
)
2775 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
2777 /* Flush the async file first. */
2778 if (target_is_async_p ())
2779 async_file_flush ();
2781 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
2783 /* If at least one stop was reported, there may be more. A single
2784 SIGCHLD can signal more than one child stop. */
2785 if (target_is_async_p ()
2786 && (target_options
& TARGET_WNOHANG
) != 0
2787 && !ptid_equal (event_ptid
, null_ptid
))
2793 /* Send a signal to an LWP. */
2796 kill_lwp (unsigned long lwpid
, int signo
)
2798 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2799 fails, then we are not using nptl threads and we should be using kill. */
2803 static int tkill_failed
;
2810 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2811 if (errno
!= ENOSYS
)
2818 return kill (lwpid
, signo
);
2822 linux_stop_lwp (struct lwp_info
*lwp
)
2828 send_sigstop (struct lwp_info
*lwp
)
2832 pid
= lwpid_of (lwp
);
2834 /* If we already have a pending stop signal for this process, don't
2836 if (lwp
->stop_expected
)
2839 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
2845 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
2847 lwp
->stop_expected
= 1;
2848 kill_lwp (pid
, SIGSTOP
);
2852 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
2854 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2856 /* Ignore EXCEPT. */
2867 /* Increment the suspend count of an LWP, and stop it, if not stopped
2870 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
2873 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2875 /* Ignore EXCEPT. */
2881 return send_sigstop_callback (entry
, except
);
2885 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
2887 /* It's dead, really. */
2890 /* Store the exit status for later. */
2891 lwp
->status_pending_p
= 1;
2892 lwp
->status_pending
= wstat
;
2894 /* Prevent trying to stop it. */
2897 /* No further stops are expected from a dead lwp. */
2898 lwp
->stop_expected
= 0;
2902 wait_for_sigstop (struct inferior_list_entry
*entry
)
2904 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2905 struct thread_info
*saved_inferior
;
2914 fprintf (stderr
, "wait_for_sigstop: LWP %ld already stopped\n",
2919 saved_inferior
= current_inferior
;
2920 if (saved_inferior
!= NULL
)
2921 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
2923 saved_tid
= null_ptid
; /* avoid bogus unused warning */
2925 ptid
= lwp
->head
.id
;
2928 fprintf (stderr
, "wait_for_sigstop: pulling one event\n");
2930 pid
= linux_wait_for_event (ptid
, &wstat
, __WALL
);
2932 /* If we stopped with a non-SIGSTOP signal, save it for later
2933 and record the pending SIGSTOP. If the process exited, just
2935 if (WIFSTOPPED (wstat
))
2938 fprintf (stderr
, "LWP %ld stopped with signal %d\n",
2939 lwpid_of (lwp
), WSTOPSIG (wstat
));
2941 if (WSTOPSIG (wstat
) != SIGSTOP
)
2944 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
2945 lwpid_of (lwp
), wstat
);
2947 lwp
->status_pending_p
= 1;
2948 lwp
->status_pending
= wstat
;
2954 fprintf (stderr
, "Process %d exited while stopping LWPs\n", pid
);
2956 lwp
= find_lwp_pid (pid_to_ptid (pid
));
2959 /* Leave this status pending for the next time we're able to
2960 report it. In the mean time, we'll report this lwp as
2961 dead to GDB, so GDB doesn't try to read registers and
2962 memory from it. This can only happen if this was the
2963 last thread of the process; otherwise, PID is removed
2964 from the thread tables before linux_wait_for_event
2966 mark_lwp_dead (lwp
, wstat
);
2970 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
2971 current_inferior
= saved_inferior
;
2975 fprintf (stderr
, "Previously current thread died.\n");
2979 /* We can't change the current inferior behind GDB's back,
2980 otherwise, a subsequent command may apply to the wrong
2982 current_inferior
= NULL
;
2986 /* Set a valid thread as current. */
2987 set_desired_inferior (0);
2992 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
2993 move it out, because we need to report the stop event to GDB. For
2994 example, if the user puts a breakpoint in the jump pad, it's
2995 because she wants to debug it. */
2998 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3000 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3001 struct thread_info
*thread
= get_lwp_thread (lwp
);
3003 gdb_assert (lwp
->suspended
== 0);
3004 gdb_assert (lwp
->stopped
);
3006 /* Allow debugging the jump pad, gdb_collect, etc.. */
3007 return (supports_fast_tracepoints ()
3008 && agent_loaded_p ()
3009 && (gdb_breakpoint_here (lwp
->stop_pc
)
3010 || lwp
->stopped_by_watchpoint
3011 || thread
->last_resume_kind
== resume_step
)
3012 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3016 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3018 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3019 struct thread_info
*thread
= get_lwp_thread (lwp
);
3022 gdb_assert (lwp
->suspended
== 0);
3023 gdb_assert (lwp
->stopped
);
3025 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3027 /* Allow debugging the jump pad, gdb_collect, etc. */
3028 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3029 && !lwp
->stopped_by_watchpoint
3030 && thread
->last_resume_kind
!= resume_step
3031 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3035 "LWP %ld needs stabilizing (in jump pad)\n",
3040 lwp
->status_pending_p
= 0;
3041 enqueue_one_deferred_signal (lwp
, wstat
);
3045 "Signal %d for LWP %ld deferred "
3047 WSTOPSIG (*wstat
), lwpid_of (lwp
));
3050 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3057 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3059 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3068 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3069 If SUSPEND, then also increase the suspend count of every LWP,
3073 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3075 stopping_threads
= 1;
3078 find_inferior (&all_lwps
, suspend_and_send_sigstop_callback
, except
);
3080 find_inferior (&all_lwps
, send_sigstop_callback
, except
);
3081 for_each_inferior (&all_lwps
, wait_for_sigstop
);
3082 stopping_threads
= 0;
3085 /* Resume execution of the inferior process.
3086 If STEP is nonzero, single-step it.
3087 If SIGNAL is nonzero, give it that signal. */
3090 linux_resume_one_lwp (struct lwp_info
*lwp
,
3091 int step
, int signal
, siginfo_t
*info
)
3093 struct thread_info
*saved_inferior
;
3094 int fast_tp_collecting
;
3096 if (lwp
->stopped
== 0)
3099 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3101 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3103 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3104 user used the "jump" command, or "set $pc = foo"). */
3105 if (lwp
->stop_pc
!= get_pc (lwp
))
3107 /* Collecting 'while-stepping' actions doesn't make sense
3109 release_while_stepping_state_list (get_lwp_thread (lwp
));
3112 /* If we have pending signals or status, and a new signal, enqueue the
3113 signal. Also enqueue the signal if we are waiting to reinsert a
3114 breakpoint; it will be picked up again below. */
3116 && (lwp
->status_pending_p
3117 || lwp
->pending_signals
!= NULL
3118 || lwp
->bp_reinsert
!= 0
3119 || fast_tp_collecting
))
3121 struct pending_signals
*p_sig
;
3122 p_sig
= xmalloc (sizeof (*p_sig
));
3123 p_sig
->prev
= lwp
->pending_signals
;
3124 p_sig
->signal
= signal
;
3126 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3128 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3129 lwp
->pending_signals
= p_sig
;
3132 if (lwp
->status_pending_p
)
3135 fprintf (stderr
, "Not resuming lwp %ld (%s, signal %d, stop %s);"
3136 " has pending status\n",
3137 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3138 lwp
->stop_expected
? "expected" : "not expected");
3142 saved_inferior
= current_inferior
;
3143 current_inferior
= get_lwp_thread (lwp
);
3146 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
3147 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3148 lwp
->stop_expected
? "expected" : "not expected");
3150 /* This bit needs some thinking about. If we get a signal that
3151 we must report while a single-step reinsert is still pending,
3152 we often end up resuming the thread. It might be better to
3153 (ew) allow a stack of pending events; then we could be sure that
3154 the reinsert happened right away and not lose any signals.
3156 Making this stack would also shrink the window in which breakpoints are
3157 uninserted (see comment in linux_wait_for_lwp) but not enough for
3158 complete correctness, so it won't solve that problem. It may be
3159 worthwhile just to solve this one, however. */
3160 if (lwp
->bp_reinsert
!= 0)
3163 fprintf (stderr
, " pending reinsert at 0x%s\n",
3164 paddress (lwp
->bp_reinsert
));
3166 if (lwp
->bp_reinsert
!= 0 && can_hardware_single_step ())
3168 if (fast_tp_collecting
== 0)
3171 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
3173 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
3180 /* Postpone any pending signal. It was enqueued above. */
3184 if (fast_tp_collecting
== 1)
3188 lwp %ld wants to get out of fast tracepoint jump pad (exit-jump-pad-bkpt)\n",
3191 /* Postpone any pending signal. It was enqueued above. */
3194 else if (fast_tp_collecting
== 2)
3198 lwp %ld wants to get out of fast tracepoint jump pad single-stepping\n",
3201 if (can_hardware_single_step ())
3204 fatal ("moving out of jump pad single-stepping"
3205 " not implemented on this target");
3207 /* Postpone any pending signal. It was enqueued above. */
3211 /* If we have while-stepping actions in this thread set it stepping.
3212 If we have a signal to deliver, it may or may not be set to
3213 SIG_IGN, we don't know. Assume so, and allow collecting
3214 while-stepping into a signal handler. A possible smart thing to
3215 do would be to set an internal breakpoint at the signal return
3216 address, continue, and carry on catching this while-stepping
3217 action only when that breakpoint is hit. A future
3219 if (get_lwp_thread (lwp
)->while_stepping
!= NULL
3220 && can_hardware_single_step ())
3224 "lwp %ld has a while-stepping action -> forcing step.\n",
3229 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
3231 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
3232 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
3233 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
3236 /* If we have pending signals, consume one unless we are trying to
3237 reinsert a breakpoint or we're trying to finish a fast tracepoint
3239 if (lwp
->pending_signals
!= NULL
3240 && lwp
->bp_reinsert
== 0
3241 && fast_tp_collecting
== 0)
3243 struct pending_signals
**p_sig
;
3245 p_sig
= &lwp
->pending_signals
;
3246 while ((*p_sig
)->prev
!= NULL
)
3247 p_sig
= &(*p_sig
)->prev
;
3249 signal
= (*p_sig
)->signal
;
3250 if ((*p_sig
)->info
.si_signo
!= 0)
3251 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), 0, &(*p_sig
)->info
);
3257 if (the_low_target
.prepare_to_resume
!= NULL
)
3258 the_low_target
.prepare_to_resume (lwp
);
3260 regcache_invalidate_one ((struct inferior_list_entry
*)
3261 get_lwp_thread (lwp
));
3264 lwp
->stopped_by_watchpoint
= 0;
3265 lwp
->stepping
= step
;
3266 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
), 0,
3267 /* Coerce to a uintptr_t first to avoid potential gcc warning
3268 of coercing an 8 byte integer to a 4 byte pointer. */
3269 (PTRACE_ARG4_TYPE
) (uintptr_t) signal
);
3271 current_inferior
= saved_inferior
;
3274 /* ESRCH from ptrace either means that the thread was already
3275 running (an error) or that it is gone (a race condition). If
3276 it's gone, we will get a notification the next time we wait,
3277 so we can ignore the error. We could differentiate these
3278 two, but it's tricky without waiting; the thread still exists
3279 as a zombie, so sending it signal 0 would succeed. So just
3284 perror_with_name ("ptrace");
3288 struct thread_resume_array
3290 struct thread_resume
*resume
;
3294 /* This function is called once per thread. We look up the thread
3295 in RESUME_PTR, and mark the thread with a pointer to the appropriate
3298 This algorithm is O(threads * resume elements), but resume elements
3299 is small (and will remain small at least until GDB supports thread
3302 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3304 struct lwp_info
*lwp
;
3305 struct thread_info
*thread
;
3307 struct thread_resume_array
*r
;
3309 thread
= (struct thread_info
*) entry
;
3310 lwp
= get_thread_lwp (thread
);
3313 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3315 ptid_t ptid
= r
->resume
[ndx
].thread
;
3316 if (ptid_equal (ptid
, minus_one_ptid
)
3317 || ptid_equal (ptid
, entry
->id
)
3318 || (ptid_is_pid (ptid
)
3319 && (ptid_get_pid (ptid
) == pid_of (lwp
)))
3320 || (ptid_get_lwp (ptid
) == -1
3321 && (ptid_get_pid (ptid
) == pid_of (lwp
))))
3323 if (r
->resume
[ndx
].kind
== resume_stop
3324 && thread
->last_resume_kind
== resume_stop
)
3327 fprintf (stderr
, "already %s LWP %ld at GDB's request\n",
3328 thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
3336 lwp
->resume
= &r
->resume
[ndx
];
3337 thread
->last_resume_kind
= lwp
->resume
->kind
;
3339 /* If we had a deferred signal to report, dequeue one now.
3340 This can happen if LWP gets more than one signal while
3341 trying to get out of a jump pad. */
3343 && !lwp
->status_pending_p
3344 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3346 lwp
->status_pending_p
= 1;
3350 "Dequeueing deferred signal %d for LWP %ld, "
3351 "leaving status pending.\n",
3352 WSTOPSIG (lwp
->status_pending
), lwpid_of (lwp
));
3359 /* No resume action for this thread. */
3366 /* Set *FLAG_P if this lwp has an interesting status pending. */
3368 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3370 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3372 /* LWPs which will not be resumed are not interesting, because
3373 we might not wait for them next time through linux_wait. */
3374 if (lwp
->resume
== NULL
)
3377 if (lwp
->status_pending_p
)
3378 * (int *) flag_p
= 1;
3383 /* Return 1 if this lwp that GDB wants running is stopped at an
3384 internal breakpoint that we need to step over. It assumes that any
3385 required STOP_PC adjustment has already been propagated to the
3386 inferior's regcache. */
3389 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3391 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3392 struct thread_info
*thread
;
3393 struct thread_info
*saved_inferior
;
3396 /* LWPs which will not be resumed are not interesting, because we
3397 might not wait for them next time through linux_wait. */
3403 "Need step over [LWP %ld]? Ignoring, not stopped\n",
3408 thread
= get_lwp_thread (lwp
);
3410 if (thread
->last_resume_kind
== resume_stop
)
3414 "Need step over [LWP %ld]? Ignoring, should remain stopped\n",
3419 gdb_assert (lwp
->suspended
>= 0);
3425 "Need step over [LWP %ld]? Ignoring, suspended\n",
3430 if (!lwp
->need_step_over
)
3434 "Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
3437 if (lwp
->status_pending_p
)
3441 "Need step over [LWP %ld]? Ignoring, has pending status.\n",
3446 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3450 /* If the PC has changed since we stopped, then don't do anything,
3451 and let the breakpoint/tracepoint be hit. This happens if, for
3452 instance, GDB handled the decr_pc_after_break subtraction itself,
3453 GDB is OOL stepping this thread, or the user has issued a "jump"
3454 command, or poked thread's registers herself. */
3455 if (pc
!= lwp
->stop_pc
)
3459 "Need step over [LWP %ld]? Cancelling, PC was changed. "
3460 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3461 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
3463 lwp
->need_step_over
= 0;
3467 saved_inferior
= current_inferior
;
3468 current_inferior
= thread
;
3470 /* We can only step over breakpoints we know about. */
3471 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3473 /* Don't step over a breakpoint that GDB expects to hit
3474 though. If the condition is being evaluated on the target's side
3475 and it evaluate to false, step over this breakpoint as well. */
3476 if (gdb_breakpoint_here (pc
)
3477 && gdb_condition_true_at_breakpoint (pc
))
3481 "Need step over [LWP %ld]? yes, but found"
3482 " GDB breakpoint at 0x%s; skipping step over\n",
3483 lwpid_of (lwp
), paddress (pc
));
3485 current_inferior
= saved_inferior
;
3492 "Need step over [LWP %ld]? yes, "
3493 "found breakpoint at 0x%s\n",
3494 lwpid_of (lwp
), paddress (pc
));
3496 /* We've found an lwp that needs stepping over --- return 1 so
3497 that find_inferior stops looking. */
3498 current_inferior
= saved_inferior
;
3500 /* If the step over is cancelled, this is set again. */
3501 lwp
->need_step_over
= 0;
3506 current_inferior
= saved_inferior
;
3510 "Need step over [LWP %ld]? No, no breakpoint found at 0x%s\n",
3511 lwpid_of (lwp
), paddress (pc
));
3516 /* Start a step-over operation on LWP. When LWP stopped at a
3517 breakpoint, to make progress, we need to remove the breakpoint out
3518 of the way. If we let other threads run while we do that, they may
3519 pass by the breakpoint location and miss hitting it. To avoid
3520 that, a step-over momentarily stops all threads while LWP is
3521 single-stepped while the breakpoint is temporarily uninserted from
3522 the inferior. When the single-step finishes, we reinsert the
3523 breakpoint, and let all threads that are supposed to be running,
3526 On targets that don't support hardware single-step, we don't
3527 currently support full software single-stepping. Instead, we only
3528 support stepping over the thread event breakpoint, by asking the
3529 low target where to place a reinsert breakpoint. Since this
3530 routine assumes the breakpoint being stepped over is a thread event
3531 breakpoint, it usually assumes the return address of the current
3532 function is a good enough place to set the reinsert breakpoint. */
3535 start_step_over (struct lwp_info
*lwp
)
3537 struct thread_info
*saved_inferior
;
3543 "Starting step-over on LWP %ld. Stopping all threads\n",
3546 stop_all_lwps (1, lwp
);
3547 gdb_assert (lwp
->suspended
== 0);
3550 fprintf (stderr
, "Done stopping all threads for step-over.\n");
3552 /* Note, we should always reach here with an already adjusted PC,
3553 either by GDB (if we're resuming due to GDB's request), or by our
3554 caller, if we just finished handling an internal breakpoint GDB
3555 shouldn't care about. */
3558 saved_inferior
= current_inferior
;
3559 current_inferior
= get_lwp_thread (lwp
);
3561 lwp
->bp_reinsert
= pc
;
3562 uninsert_breakpoints_at (pc
);
3563 uninsert_fast_tracepoint_jumps_at (pc
);
3565 if (can_hardware_single_step ())
3571 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3572 set_reinsert_breakpoint (raddr
);
3576 current_inferior
= saved_inferior
;
3578 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3580 /* Require next event from this LWP. */
3581 step_over_bkpt
= lwp
->head
.id
;
3585 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3586 start_step_over, if still there, and delete any reinsert
3587 breakpoints we've set, on non hardware single-step targets. */
3590 finish_step_over (struct lwp_info
*lwp
)
3592 if (lwp
->bp_reinsert
!= 0)
3595 fprintf (stderr
, "Finished step over.\n");
3597 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3598 may be no breakpoint to reinsert there by now. */
3599 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3600 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3602 lwp
->bp_reinsert
= 0;
3604 /* Delete any software-single-step reinsert breakpoints. No
3605 longer needed. We don't have to worry about other threads
3606 hitting this trap, and later not being able to explain it,
3607 because we were stepping over a breakpoint, and we hold all
3608 threads but LWP stopped while doing that. */
3609 if (!can_hardware_single_step ())
3610 delete_reinsert_breakpoints ();
3612 step_over_bkpt
= null_ptid
;
3619 /* This function is called once per thread. We check the thread's resume
3620 request, which will tell us whether to resume, step, or leave the thread
3621 stopped; and what signal, if any, it should be sent.
3623 For threads which we aren't explicitly told otherwise, we preserve
3624 the stepping flag; this is used for stepping over gdbserver-placed
3627 If pending_flags was set in any thread, we queue any needed
3628 signals, since we won't actually resume. We already have a pending
3629 event to report, so we don't need to preserve any step requests;
3630 they should be re-issued if necessary. */
3633 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3635 struct lwp_info
*lwp
;
3636 struct thread_info
*thread
;
3638 int leave_all_stopped
= * (int *) arg
;
3641 thread
= (struct thread_info
*) entry
;
3642 lwp
= get_thread_lwp (thread
);
3644 if (lwp
->resume
== NULL
)
3647 if (lwp
->resume
->kind
== resume_stop
)
3650 fprintf (stderr
, "resume_stop request for LWP %ld\n", lwpid_of (lwp
));
3655 fprintf (stderr
, "stopping LWP %ld\n", lwpid_of (lwp
));
3657 /* Stop the thread, and wait for the event asynchronously,
3658 through the event loop. */
3664 fprintf (stderr
, "already stopped LWP %ld\n",
3667 /* The LWP may have been stopped in an internal event that
3668 was not meant to be notified back to GDB (e.g., gdbserver
3669 breakpoint), so we should be reporting a stop event in
3672 /* If the thread already has a pending SIGSTOP, this is a
3673 no-op. Otherwise, something later will presumably resume
3674 the thread and this will cause it to cancel any pending
3675 operation, due to last_resume_kind == resume_stop. If
3676 the thread already has a pending status to report, we
3677 will still report it the next time we wait - see
3678 status_pending_p_callback. */
3680 /* If we already have a pending signal to report, then
3681 there's no need to queue a SIGSTOP, as this means we're
3682 midway through moving the LWP out of the jumppad, and we
3683 will report the pending signal as soon as that is
3685 if (lwp
->pending_signals_to_report
== NULL
)
3689 /* For stop requests, we're done. */
3691 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3695 /* If this thread which is about to be resumed has a pending status,
3696 then don't resume any threads - we can just report the pending
3697 status. Make sure to queue any signals that would otherwise be
3698 sent. In all-stop mode, we do this decision based on if *any*
3699 thread has a pending status. If there's a thread that needs the
3700 step-over-breakpoint dance, then don't resume any other thread
3701 but that particular one. */
3702 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
3707 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
3709 step
= (lwp
->resume
->kind
== resume_step
);
3710 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
3715 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
3717 /* If we have a new signal, enqueue the signal. */
3718 if (lwp
->resume
->sig
!= 0)
3720 struct pending_signals
*p_sig
;
3721 p_sig
= xmalloc (sizeof (*p_sig
));
3722 p_sig
->prev
= lwp
->pending_signals
;
3723 p_sig
->signal
= lwp
->resume
->sig
;
3724 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3726 /* If this is the same signal we were previously stopped by,
3727 make sure to queue its siginfo. We can ignore the return
3728 value of ptrace; if it fails, we'll skip
3729 PTRACE_SETSIGINFO. */
3730 if (WIFSTOPPED (lwp
->last_status
)
3731 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
3732 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), 0, &p_sig
->info
);
3734 lwp
->pending_signals
= p_sig
;
3738 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3744 linux_resume (struct thread_resume
*resume_info
, size_t n
)
3746 struct thread_resume_array array
= { resume_info
, n
};
3747 struct lwp_info
*need_step_over
= NULL
;
3749 int leave_all_stopped
;
3751 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
3753 /* If there is a thread which would otherwise be resumed, which has
3754 a pending status, then don't resume any threads - we can just
3755 report the pending status. Make sure to queue any signals that
3756 would otherwise be sent. In non-stop mode, we'll apply this
3757 logic to each thread individually. We consume all pending events
3758 before considering to start a step-over (in all-stop). */
3761 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
3763 /* If there is a thread which would otherwise be resumed, which is
3764 stopped at a breakpoint that needs stepping over, then don't
3765 resume any threads - have it step over the breakpoint with all
3766 other threads stopped, then resume all threads again. Make sure
3767 to queue any signals that would otherwise be delivered or
3769 if (!any_pending
&& supports_breakpoints ())
3771 = (struct lwp_info
*) find_inferior (&all_lwps
,
3772 need_step_over_p
, NULL
);
3774 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
3778 if (need_step_over
!= NULL
)
3779 fprintf (stderr
, "Not resuming all, need step over\n");
3780 else if (any_pending
)
3782 "Not resuming, all-stop and found "
3783 "an LWP with pending status\n");
3785 fprintf (stderr
, "Resuming, no pending status or step over needed\n");
3788 /* Even if we're leaving threads stopped, queue all signals we'd
3789 otherwise deliver. */
3790 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
3793 start_step_over (need_step_over
);
3796 /* This function is called once per thread. We check the thread's
3797 last resume request, which will tell us whether to resume, step, or
3798 leave the thread stopped. Any signal the client requested to be
3799 delivered has already been enqueued at this point.
3801 If any thread that GDB wants running is stopped at an internal
3802 breakpoint that needs stepping over, we start a step-over operation
3803 on that particular thread, and leave all others stopped. */
3806 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3808 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3809 struct thread_info
*thread
;
3817 "proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
3822 fprintf (stderr
, " LWP %ld already running\n", lwpid_of (lwp
));
3826 thread
= get_lwp_thread (lwp
);
3828 if (thread
->last_resume_kind
== resume_stop
3829 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
3832 fprintf (stderr
, " client wants LWP to remain %ld stopped\n",
3837 if (lwp
->status_pending_p
)
3840 fprintf (stderr
, " LWP %ld has pending status, leaving stopped\n",
3845 gdb_assert (lwp
->suspended
>= 0);
3850 fprintf (stderr
, " LWP %ld is suspended\n", lwpid_of (lwp
));
3854 if (thread
->last_resume_kind
== resume_stop
3855 && lwp
->pending_signals_to_report
== NULL
3856 && lwp
->collecting_fast_tracepoint
== 0)
3858 /* We haven't reported this LWP as stopped yet (otherwise, the
3859 last_status.kind check above would catch it, and we wouldn't
3860 reach here. This LWP may have been momentarily paused by a
3861 stop_all_lwps call while handling for example, another LWP's
3862 step-over. In that case, the pending expected SIGSTOP signal
3863 that was queued at vCont;t handling time will have already
3864 been consumed by wait_for_sigstop, and so we need to requeue
3865 another one here. Note that if the LWP already has a SIGSTOP
3866 pending, this is a no-op. */
3870 "Client wants LWP %ld to stop. "
3871 "Making sure it has a SIGSTOP pending\n",
3877 step
= thread
->last_resume_kind
== resume_step
;
3878 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3883 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3885 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3891 gdb_assert (lwp
->suspended
>= 0);
3893 return proceed_one_lwp (entry
, except
);
3896 /* When we finish a step-over, set threads running again. If there's
3897 another thread that may need a step-over, now's the time to start
3898 it. Eventually, we'll move all threads past their breakpoints. */
3901 proceed_all_lwps (void)
3903 struct lwp_info
*need_step_over
;
3905 /* If there is a thread which would otherwise be resumed, which is
3906 stopped at a breakpoint that needs stepping over, then don't
3907 resume any threads - have it step over the breakpoint with all
3908 other threads stopped, then resume all threads again. */
3910 if (supports_breakpoints ())
3913 = (struct lwp_info
*) find_inferior (&all_lwps
,
3914 need_step_over_p
, NULL
);
3916 if (need_step_over
!= NULL
)
3919 fprintf (stderr
, "proceed_all_lwps: found "
3920 "thread %ld needing a step-over\n",
3921 lwpid_of (need_step_over
));
3923 start_step_over (need_step_over
);
3929 fprintf (stderr
, "Proceeding, no step-over needed\n");
3931 find_inferior (&all_lwps
, proceed_one_lwp
, NULL
);
3934 /* Stopped LWPs that the client wanted to be running, that don't have
3935 pending statuses, are set to run again, except for EXCEPT, if not
3936 NULL. This undoes a stop_all_lwps call. */
3939 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
3945 "unstopping all lwps, except=(LWP %ld)\n", lwpid_of (except
));
3948 "unstopping all lwps\n");
3952 find_inferior (&all_lwps
, unsuspend_and_proceed_one_lwp
, except
);
3954 find_inferior (&all_lwps
, proceed_one_lwp
, except
);
3958 #ifdef HAVE_LINUX_REGSETS
3960 #define use_linux_regsets 1
3963 regsets_fetch_inferior_registers (struct regcache
*regcache
)
3965 struct regset_info
*regset
;
3966 int saw_general_regs
= 0;
3970 regset
= target_regsets
;
3972 pid
= lwpid_of (get_thread_lwp (current_inferior
));
3973 while (regset
->size
>= 0)
3978 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
3984 buf
= xmalloc (regset
->size
);
3986 nt_type
= regset
->nt_type
;
3990 iov
.iov_len
= regset
->size
;
3991 data
= (void *) &iov
;
3997 res
= ptrace (regset
->get_request
, pid
,
3998 (PTRACE_ARG3_TYPE
) (long) nt_type
, data
);
4000 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4006 /* If we get EIO on a regset, do not try it again for
4008 disabled_regsets
[regset
- target_regsets
] = 1;
4015 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4020 else if (regset
->type
== GENERAL_REGS
)
4021 saw_general_regs
= 1;
4022 regset
->store_function (regcache
, buf
);
4026 if (saw_general_regs
)
4033 regsets_store_inferior_registers (struct regcache
*regcache
)
4035 struct regset_info
*regset
;
4036 int saw_general_regs
= 0;
4040 regset
= target_regsets
;
4042 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4043 while (regset
->size
>= 0)
4048 if (regset
->size
== 0 || disabled_regsets
[regset
- target_regsets
])
4054 buf
= xmalloc (regset
->size
);
4056 /* First fill the buffer with the current register set contents,
4057 in case there are any items in the kernel's regset that are
4058 not in gdbserver's regcache. */
4060 nt_type
= regset
->nt_type
;
4064 iov
.iov_len
= regset
->size
;
4065 data
= (void *) &iov
;
4071 res
= ptrace (regset
->get_request
, pid
,
4072 (PTRACE_ARG3_TYPE
) (long) nt_type
, data
);
4074 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4079 /* Then overlay our cached registers on that. */
4080 regset
->fill_function (regcache
, buf
);
4082 /* Only now do we write the register set. */
4084 res
= ptrace (regset
->set_request
, pid
,
4085 (PTRACE_ARG3_TYPE
) (long) nt_type
, data
);
4087 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4095 /* If we get EIO on a regset, do not try it again for
4097 disabled_regsets
[regset
- target_regsets
] = 1;
4101 else if (errno
== ESRCH
)
4103 /* At this point, ESRCH should mean the process is
4104 already gone, in which case we simply ignore attempts
4105 to change its registers. See also the related
4106 comment in linux_resume_one_lwp. */
4112 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4115 else if (regset
->type
== GENERAL_REGS
)
4116 saw_general_regs
= 1;
4120 if (saw_general_regs
)
4126 #else /* !HAVE_LINUX_REGSETS */
4128 #define use_linux_regsets 0
4129 #define regsets_fetch_inferior_registers(regcache) 1
4130 #define regsets_store_inferior_registers(regcache) 1
4134 /* Return 1 if register REGNO is supported by one of the regset ptrace
4135 calls or 0 if it has to be transferred individually. */
4138 linux_register_in_regsets (int regno
)
4140 unsigned char mask
= 1 << (regno
% 8);
4141 size_t index
= regno
/ 8;
4143 return (use_linux_regsets
4144 && (the_low_target
.regset_bitmap
== NULL
4145 || (the_low_target
.regset_bitmap
[index
] & mask
) != 0));
4148 #ifdef HAVE_LINUX_USRREGS
4151 register_addr (int regnum
)
4155 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
4156 error ("Invalid register number %d.", regnum
);
4158 addr
= the_low_target
.regmap
[regnum
];
4163 /* Fetch one register. */
4165 fetch_register (struct regcache
*regcache
, int regno
)
4172 if (regno
>= the_low_target
.num_regs
)
4174 if ((*the_low_target
.cannot_fetch_register
) (regno
))
4177 regaddr
= register_addr (regno
);
4181 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4182 & -sizeof (PTRACE_XFER_TYPE
));
4183 buf
= alloca (size
);
4185 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4186 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4189 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
4190 ptrace (PTRACE_PEEKUSER
, pid
,
4191 /* Coerce to a uintptr_t first to avoid potential gcc warning
4192 of coercing an 8 byte integer to a 4 byte pointer. */
4193 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
, 0);
4194 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4196 error ("reading register %d: %s", regno
, strerror (errno
));
4199 if (the_low_target
.supply_ptrace_register
)
4200 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
4202 supply_register (regcache
, regno
, buf
);
4205 /* Store one register. */
4207 store_register (struct regcache
*regcache
, int regno
)
4214 if (regno
>= the_low_target
.num_regs
)
4216 if ((*the_low_target
.cannot_store_register
) (regno
))
4219 regaddr
= register_addr (regno
);
4223 size
= ((register_size (regno
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4224 & -sizeof (PTRACE_XFER_TYPE
));
4225 buf
= alloca (size
);
4226 memset (buf
, 0, size
);
4228 if (the_low_target
.collect_ptrace_register
)
4229 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
4231 collect_register (regcache
, regno
, buf
);
4233 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4234 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4237 ptrace (PTRACE_POKEUSER
, pid
,
4238 /* Coerce to a uintptr_t first to avoid potential gcc warning
4239 about coercing an 8 byte integer to a 4 byte pointer. */
4240 (PTRACE_ARG3_TYPE
) (uintptr_t) regaddr
,
4241 (PTRACE_ARG4_TYPE
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
4244 /* At this point, ESRCH should mean the process is
4245 already gone, in which case we simply ignore attempts
4246 to change its registers. See also the related
4247 comment in linux_resume_one_lwp. */
4251 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
4252 error ("writing register %d: %s", regno
, strerror (errno
));
4254 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4258 /* Fetch all registers, or just one, from the child process.
4259 If REGNO is -1, do this for all registers, skipping any that are
4260 assumed to have been retrieved by regsets_fetch_inferior_registers,
4261 unless ALL is non-zero.
4262 Otherwise, REGNO specifies which register (so we can save time). */
4264 usr_fetch_inferior_registers (struct regcache
*regcache
, int regno
, int all
)
4268 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4269 if (all
|| !linux_register_in_regsets (regno
))
4270 fetch_register (regcache
, regno
);
4273 fetch_register (regcache
, regno
);
4276 /* Store our register values back into the inferior.
4277 If REGNO is -1, do this for all registers, skipping any that are
4278 assumed to have been saved by regsets_store_inferior_registers,
4279 unless ALL is non-zero.
4280 Otherwise, REGNO specifies which register (so we can save time). */
4282 usr_store_inferior_registers (struct regcache
*regcache
, int regno
, int all
)
4286 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4287 if (all
|| !linux_register_in_regsets (regno
))
4288 store_register (regcache
, regno
);
4291 store_register (regcache
, regno
);
4294 #else /* !HAVE_LINUX_USRREGS */
4296 #define usr_fetch_inferior_registers(regcache, regno, all) do {} while (0)
4297 #define usr_store_inferior_registers(regcache, regno, all) do {} while (0)
4303 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4310 if (the_low_target
.fetch_register
!= NULL
)
4311 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
4312 (*the_low_target
.fetch_register
) (regcache
, regno
);
4314 all
= regsets_fetch_inferior_registers (regcache
);
4315 usr_fetch_inferior_registers (regcache
, -1, all
);
4319 if (the_low_target
.fetch_register
!= NULL
4320 && (*the_low_target
.fetch_register
) (regcache
, regno
))
4323 use_regsets
= linux_register_in_regsets (regno
);
4325 all
= regsets_fetch_inferior_registers (regcache
);
4326 if (!use_regsets
|| all
)
4327 usr_fetch_inferior_registers (regcache
, regno
, 1);
4332 linux_store_registers (struct regcache
*regcache
, int regno
)
4339 all
= regsets_store_inferior_registers (regcache
);
4340 usr_store_inferior_registers (regcache
, regno
, all
);
4344 use_regsets
= linux_register_in_regsets (regno
);
4346 all
= regsets_store_inferior_registers (regcache
);
4347 if (!use_regsets
|| all
)
4348 usr_store_inferior_registers (regcache
, regno
, 1);
4353 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4354 to debugger memory starting at MYADDR. */
4357 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4360 /* Round starting address down to longword boundary. */
4361 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4362 /* Round ending address up; get number of longwords that makes. */
4364 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4365 / sizeof (PTRACE_XFER_TYPE
);
4366 /* Allocate buffer of that many longwords. */
4367 register PTRACE_XFER_TYPE
*buffer
4368 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4371 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4373 /* Try using /proc. Don't bother for one word. */
4374 if (len
>= 3 * sizeof (long))
4376 /* We could keep this file open and cache it - possibly one per
4377 thread. That requires some juggling, but is even faster. */
4378 sprintf (filename
, "/proc/%d/mem", pid
);
4379 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4383 /* If pread64 is available, use it. It's faster if the kernel
4384 supports it (only one syscall), and it's 64-bit safe even on
4385 32-bit platforms (for instance, SPARC debugging a SPARC64
4388 if (pread64 (fd
, myaddr
, len
, memaddr
) != len
)
4390 if (lseek (fd
, memaddr
, SEEK_SET
) == -1 || read (fd
, myaddr
, len
) != len
)
4402 /* Read all the longwords */
4403 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4406 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4407 about coercing an 8 byte integer to a 4 byte pointer. */
4408 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4409 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4414 /* Copy appropriate bytes out of the buffer. */
4416 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4422 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4423 memory at MEMADDR. On failure (cannot write to the inferior)
4424 returns the value of errno. */
4427 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4430 /* Round starting address down to longword boundary. */
4431 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4432 /* Round ending address up; get number of longwords that makes. */
4434 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4435 / sizeof (PTRACE_XFER_TYPE
);
4437 /* Allocate buffer of that many longwords. */
4438 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4439 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4441 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4445 /* Dump up to four bytes. */
4446 unsigned int val
= * (unsigned int *) myaddr
;
4452 val
= val
& 0xffffff;
4453 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4454 val
, (long)memaddr
);
4457 /* Fill start and end extra bytes of buffer with existing memory data. */
4460 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4461 about coercing an 8 byte integer to a 4 byte pointer. */
4462 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4463 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
, 0);
4471 = ptrace (PTRACE_PEEKTEXT
, pid
,
4472 /* Coerce to a uintptr_t first to avoid potential gcc warning
4473 about coercing an 8 byte integer to a 4 byte pointer. */
4474 (PTRACE_ARG3_TYPE
) (uintptr_t) (addr
+ (count
- 1)
4475 * sizeof (PTRACE_XFER_TYPE
)),
4481 /* Copy data to be written over corresponding part of buffer. */
4483 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4486 /* Write the entire buffer. */
4488 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4491 ptrace (PTRACE_POKETEXT
, pid
,
4492 /* Coerce to a uintptr_t first to avoid potential gcc warning
4493 about coercing an 8 byte integer to a 4 byte pointer. */
4494 (PTRACE_ARG3_TYPE
) (uintptr_t) addr
,
4495 (PTRACE_ARG4_TYPE
) buffer
[i
]);
4503 /* Non-zero if the kernel supports PTRACE_O_TRACEFORK. */
4504 static int linux_supports_tracefork_flag
;
4507 linux_enable_event_reporting (int pid
)
4509 if (!linux_supports_tracefork_flag
)
4512 ptrace (PTRACE_SETOPTIONS
, pid
, 0, (PTRACE_ARG4_TYPE
) PTRACE_O_TRACECLONE
);
4515 /* Helper functions for linux_test_for_tracefork, called via clone (). */
4518 linux_tracefork_grandchild (void *arg
)
4523 #define STACK_SIZE 4096
4526 linux_tracefork_child (void *arg
)
4528 ptrace (PTRACE_TRACEME
, 0, 0, 0);
4529 kill (getpid (), SIGSTOP
);
4531 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4534 linux_tracefork_grandchild (NULL
);
4536 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4539 __clone2 (linux_tracefork_grandchild
, arg
, STACK_SIZE
,
4540 CLONE_VM
| SIGCHLD
, NULL
);
4542 clone (linux_tracefork_grandchild
, (char *) arg
+ STACK_SIZE
,
4543 CLONE_VM
| SIGCHLD
, NULL
);
4546 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4551 /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make
4552 sure that we can enable the option, and that it had the desired
4556 linux_test_for_tracefork (void)
4558 int child_pid
, ret
, status
;
4560 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4561 char *stack
= xmalloc (STACK_SIZE
* 4);
4562 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4564 linux_supports_tracefork_flag
= 0;
4566 #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
4568 child_pid
= fork ();
4570 linux_tracefork_child (NULL
);
4572 #else /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4574 /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */
4576 child_pid
= __clone2 (linux_tracefork_child
, stack
, STACK_SIZE
,
4577 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4578 #else /* !__ia64__ */
4579 child_pid
= clone (linux_tracefork_child
, stack
+ STACK_SIZE
,
4580 CLONE_VM
| SIGCHLD
, stack
+ STACK_SIZE
* 2);
4581 #endif /* !__ia64__ */
4583 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4585 if (child_pid
== -1)
4586 perror_with_name ("clone");
4588 ret
= my_waitpid (child_pid
, &status
, 0);
4590 perror_with_name ("waitpid");
4591 else if (ret
!= child_pid
)
4592 error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret
);
4593 if (! WIFSTOPPED (status
))
4594 error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status
);
4596 ret
= ptrace (PTRACE_SETOPTIONS
, child_pid
, 0,
4597 (PTRACE_ARG4_TYPE
) PTRACE_O_TRACEFORK
);
4600 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4603 warning ("linux_test_for_tracefork: failed to kill child");
4607 ret
= my_waitpid (child_pid
, &status
, 0);
4608 if (ret
!= child_pid
)
4609 warning ("linux_test_for_tracefork: failed to wait for killed child");
4610 else if (!WIFSIGNALED (status
))
4611 warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
4612 "killed child", status
);
4617 ret
= ptrace (PTRACE_CONT
, child_pid
, 0, 0);
4619 warning ("linux_test_for_tracefork: failed to resume child");
4621 ret
= my_waitpid (child_pid
, &status
, 0);
4623 if (ret
== child_pid
&& WIFSTOPPED (status
)
4624 && status
>> 16 == PTRACE_EVENT_FORK
)
4627 ret
= ptrace (PTRACE_GETEVENTMSG
, child_pid
, 0, &second_pid
);
4628 if (ret
== 0 && second_pid
!= 0)
4632 linux_supports_tracefork_flag
= 1;
4633 my_waitpid (second_pid
, &second_status
, 0);
4634 ret
= ptrace (PTRACE_KILL
, second_pid
, 0, 0);
4636 warning ("linux_test_for_tracefork: failed to kill second child");
4637 my_waitpid (second_pid
, &status
, 0);
4641 warning ("linux_test_for_tracefork: unexpected result from waitpid "
4642 "(%d, status 0x%x)", ret
, status
);
4646 ret
= ptrace (PTRACE_KILL
, child_pid
, 0, 0);
4648 warning ("linux_test_for_tracefork: failed to kill child");
4649 my_waitpid (child_pid
, &status
, 0);
4651 while (WIFSTOPPED (status
));
4653 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4655 #endif /* defined(__UCLIBC__) && defined(HAS_NOMMU) */
4660 linux_look_up_symbols (void)
4662 #ifdef USE_THREAD_DB
4663 struct process_info
*proc
= current_process ();
4665 if (proc
->private->thread_db
!= NULL
)
4668 /* If the kernel supports tracing forks then it also supports tracing
4669 clones, and then we don't need to use the magic thread event breakpoint
4670 to learn about threads. */
4671 thread_db_init (!linux_supports_tracefork_flag
);
4676 linux_request_interrupt (void)
4678 extern unsigned long signal_pid
;
4680 if (!ptid_equal (cont_thread
, null_ptid
)
4681 && !ptid_equal (cont_thread
, minus_one_ptid
))
4683 struct lwp_info
*lwp
;
4686 lwp
= get_thread_lwp (current_inferior
);
4687 lwpid
= lwpid_of (lwp
);
4688 kill_lwp (lwpid
, SIGINT
);
4691 kill_lwp (signal_pid
, SIGINT
);
4694 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4695 to debugger memory starting at MYADDR. */
4698 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4700 char filename
[PATH_MAX
];
4702 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4704 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4706 fd
= open (filename
, O_RDONLY
);
4710 if (offset
!= (CORE_ADDR
) 0
4711 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4714 n
= read (fd
, myaddr
, len
);
4721 /* These breakpoint and watchpoint related wrapper functions simply
4722 pass on the function call if the target has registered a
4723 corresponding function. */
4726 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
4728 if (the_low_target
.insert_point
!= NULL
)
4729 return the_low_target
.insert_point (type
, addr
, len
);
4731 /* Unsupported (see target.h). */
4736 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
4738 if (the_low_target
.remove_point
!= NULL
)
4739 return the_low_target
.remove_point (type
, addr
, len
);
4741 /* Unsupported (see target.h). */
4746 linux_stopped_by_watchpoint (void)
4748 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4750 return lwp
->stopped_by_watchpoint
;
4754 linux_stopped_data_address (void)
4756 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4758 return lwp
->stopped_data_address
;
4761 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
4762 #if defined(__mcoldfire__)
4763 /* These should really be defined in the kernel's ptrace.h header. */
4764 #define PT_TEXT_ADDR 49*4
4765 #define PT_DATA_ADDR 50*4
4766 #define PT_TEXT_END_ADDR 51*4
4768 #define PT_TEXT_ADDR 220
4769 #define PT_TEXT_END_ADDR 224
4770 #define PT_DATA_ADDR 228
4771 #elif defined(__TMS320C6X__)
4772 #define PT_TEXT_ADDR (0x10000*4)
4773 #define PT_DATA_ADDR (0x10004*4)
4774 #define PT_TEXT_END_ADDR (0x10008*4)
4777 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4778 to tell gdb about. */
4781 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
4783 #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR)
4784 unsigned long text
, text_end
, data
;
4785 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4789 text
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_ADDR
, 0);
4790 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_TEXT_END_ADDR
, 0);
4791 data
= ptrace (PTRACE_PEEKUSER
, pid
, (long)PT_DATA_ADDR
, 0);
4795 /* Both text and data offsets produced at compile-time (and so
4796 used by gdb) are relative to the beginning of the program,
4797 with the data segment immediately following the text segment.
4798 However, the actual runtime layout in memory may put the data
4799 somewhere else, so when we send gdb a data base-address, we
4800 use the real data base address and subtract the compile-time
4801 data base-address from it (which is just the length of the
4802 text segment). BSS immediately follows data in both
4805 *data_p
= data
- (text_end
- text
);
4815 linux_qxfer_osdata (const char *annex
,
4816 unsigned char *readbuf
, unsigned const char *writebuf
,
4817 CORE_ADDR offset
, int len
)
4819 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
4822 /* Convert a native/host siginfo object, into/from the siginfo in the
4823 layout of the inferiors' architecture. */
4826 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
4830 if (the_low_target
.siginfo_fixup
!= NULL
)
4831 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4833 /* If there was no callback, or the callback didn't do anything,
4834 then just do a straight memcpy. */
4838 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
4840 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
4845 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
4846 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
4850 char inf_siginfo
[sizeof (siginfo_t
)];
4852 if (current_inferior
== NULL
)
4855 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4858 fprintf (stderr
, "%s siginfo for lwp %d.\n",
4859 readbuf
!= NULL
? "Reading" : "Writing",
4862 if (offset
>= sizeof (siginfo
))
4865 if (ptrace (PTRACE_GETSIGINFO
, pid
, 0, &siginfo
) != 0)
4868 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4869 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4870 inferior with a 64-bit GDBSERVER should look the same as debugging it
4871 with a 32-bit GDBSERVER, we need to convert it. */
4872 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4874 if (offset
+ len
> sizeof (siginfo
))
4875 len
= sizeof (siginfo
) - offset
;
4877 if (readbuf
!= NULL
)
4878 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4881 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4883 /* Convert back to ptrace layout before flushing it out. */
4884 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4886 if (ptrace (PTRACE_SETSIGINFO
, pid
, 0, &siginfo
) != 0)
4893 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4894 so we notice when children change state; as the handler for the
4895 sigsuspend in my_waitpid. */
4898 sigchld_handler (int signo
)
4900 int old_errno
= errno
;
4906 /* fprintf is not async-signal-safe, so call write
4908 if (write (2, "sigchld_handler\n",
4909 sizeof ("sigchld_handler\n") - 1) < 0)
4910 break; /* just ignore */
4914 if (target_is_async_p ())
4915 async_file_mark (); /* trigger a linux_wait */
4921 linux_supports_non_stop (void)
4927 linux_async (int enable
)
4929 int previous
= (linux_event_pipe
[0] != -1);
4932 fprintf (stderr
, "linux_async (%d), previous=%d\n",
4935 if (previous
!= enable
)
4938 sigemptyset (&mask
);
4939 sigaddset (&mask
, SIGCHLD
);
4941 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
4945 if (pipe (linux_event_pipe
) == -1)
4946 fatal ("creating event pipe failed.");
4948 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
4949 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
4951 /* Register the event loop handler. */
4952 add_file_handler (linux_event_pipe
[0],
4953 handle_target_event
, NULL
);
4955 /* Always trigger a linux_wait. */
4960 delete_file_handler (linux_event_pipe
[0]);
4962 close (linux_event_pipe
[0]);
4963 close (linux_event_pipe
[1]);
4964 linux_event_pipe
[0] = -1;
4965 linux_event_pipe
[1] = -1;
4968 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
4975 linux_start_non_stop (int nonstop
)
4977 /* Register or unregister from event-loop accordingly. */
4978 linux_async (nonstop
);
4983 linux_supports_multi_process (void)
4989 linux_supports_disable_randomization (void)
4991 #ifdef HAVE_PERSONALITY
4999 linux_supports_agent (void)
5004 /* Enumerate spufs IDs for process PID. */
5006 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
5012 struct dirent
*entry
;
5014 sprintf (path
, "/proc/%ld/fd", pid
);
5015 dir
= opendir (path
);
5020 while ((entry
= readdir (dir
)) != NULL
)
5026 fd
= atoi (entry
->d_name
);
5030 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
5031 if (stat (path
, &st
) != 0)
5033 if (!S_ISDIR (st
.st_mode
))
5036 if (statfs (path
, &stfs
) != 0)
5038 if (stfs
.f_type
!= SPUFS_MAGIC
)
5041 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
5043 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
5053 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
5054 object type, using the /proc file system. */
5056 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
5057 unsigned const char *writebuf
,
5058 CORE_ADDR offset
, int len
)
5060 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
5065 if (!writebuf
&& !readbuf
)
5073 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5076 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
5077 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5082 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5089 ret
= write (fd
, writebuf
, (size_t) len
);
5091 ret
= read (fd
, readbuf
, (size_t) len
);
5097 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5098 struct target_loadseg
5100 /* Core address to which the segment is mapped. */
5102 /* VMA recorded in the program header. */
5104 /* Size of this segment in memory. */
5108 # if defined PT_GETDSBT
5109 struct target_loadmap
5111 /* Protocol version number, must be zero. */
5113 /* Pointer to the DSBT table, its size, and the DSBT index. */
5114 unsigned *dsbt_table
;
5115 unsigned dsbt_size
, dsbt_index
;
5116 /* Number of segments in this map. */
5118 /* The actual memory map. */
5119 struct target_loadseg segs
[/*nsegs*/];
5121 # define LINUX_LOADMAP PT_GETDSBT
5122 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5123 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5125 struct target_loadmap
5127 /* Protocol version number, must be zero. */
5129 /* Number of segments in this map. */
5131 /* The actual memory map. */
5132 struct target_loadseg segs
[/*nsegs*/];
5134 # define LINUX_LOADMAP PTRACE_GETFDPIC
5135 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5136 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5140 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
5141 unsigned char *myaddr
, unsigned int len
)
5143 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
5145 struct target_loadmap
*data
= NULL
;
5146 unsigned int actual_length
, copy_length
;
5148 if (strcmp (annex
, "exec") == 0)
5149 addr
= (int) LINUX_LOADMAP_EXEC
;
5150 else if (strcmp (annex
, "interp") == 0)
5151 addr
= (int) LINUX_LOADMAP_INTERP
;
5155 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
5161 actual_length
= sizeof (struct target_loadmap
)
5162 + sizeof (struct target_loadseg
) * data
->nsegs
;
5164 if (offset
< 0 || offset
> actual_length
)
5167 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
5168 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
5172 # define linux_read_loadmap NULL
5173 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5176 linux_process_qsupported (const char *query
)
5178 if (the_low_target
.process_qsupported
!= NULL
)
5179 the_low_target
.process_qsupported (query
);
5183 linux_supports_tracepoints (void)
5185 if (*the_low_target
.supports_tracepoints
== NULL
)
5188 return (*the_low_target
.supports_tracepoints
) ();
5192 linux_read_pc (struct regcache
*regcache
)
5194 if (the_low_target
.get_pc
== NULL
)
5197 return (*the_low_target
.get_pc
) (regcache
);
5201 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
5203 gdb_assert (the_low_target
.set_pc
!= NULL
);
5205 (*the_low_target
.set_pc
) (regcache
, pc
);
5209 linux_thread_stopped (struct thread_info
*thread
)
5211 return get_thread_lwp (thread
)->stopped
;
5214 /* This exposes stop-all-threads functionality to other modules. */
5217 linux_pause_all (int freeze
)
5219 stop_all_lwps (freeze
, NULL
);
5222 /* This exposes unstop-all-threads functionality to other gdbserver
5226 linux_unpause_all (int unfreeze
)
5228 unstop_all_lwps (unfreeze
, NULL
);
5232 linux_prepare_to_access_memory (void)
5234 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5237 linux_pause_all (1);
5242 linux_done_accessing_memory (void)
5244 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5247 linux_unpause_all (1);
5251 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5252 CORE_ADDR collector
,
5255 CORE_ADDR
*jump_entry
,
5256 CORE_ADDR
*trampoline
,
5257 ULONGEST
*trampoline_size
,
5258 unsigned char *jjump_pad_insn
,
5259 ULONGEST
*jjump_pad_insn_size
,
5260 CORE_ADDR
*adjusted_insn_addr
,
5261 CORE_ADDR
*adjusted_insn_addr_end
,
5264 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5265 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5266 jump_entry
, trampoline
, trampoline_size
,
5267 jjump_pad_insn
, jjump_pad_insn_size
,
5268 adjusted_insn_addr
, adjusted_insn_addr_end
,
5272 static struct emit_ops
*
5273 linux_emit_ops (void)
5275 if (the_low_target
.emit_ops
!= NULL
)
5276 return (*the_low_target
.emit_ops
) ();
5282 linux_get_min_fast_tracepoint_insn_len (void)
5284 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5287 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5290 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5291 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5293 char filename
[PATH_MAX
];
5295 const int auxv_size
= is_elf64
5296 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5297 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5299 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5301 fd
= open (filename
, O_RDONLY
);
5307 while (read (fd
, buf
, auxv_size
) == auxv_size
5308 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5312 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5314 switch (aux
->a_type
)
5317 *phdr_memaddr
= aux
->a_un
.a_val
;
5320 *num_phdr
= aux
->a_un
.a_val
;
5326 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5328 switch (aux
->a_type
)
5331 *phdr_memaddr
= aux
->a_un
.a_val
;
5334 *num_phdr
= aux
->a_un
.a_val
;
5342 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5344 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5345 "phdr_memaddr = %ld, phdr_num = %d",
5346 (long) *phdr_memaddr
, *num_phdr
);
5353 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5356 get_dynamic (const int pid
, const int is_elf64
)
5358 CORE_ADDR phdr_memaddr
, relocation
;
5360 unsigned char *phdr_buf
;
5361 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5363 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5366 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5367 phdr_buf
= alloca (num_phdr
* phdr_size
);
5369 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5372 /* Compute relocation: it is expected to be 0 for "regular" executables,
5373 non-zero for PIE ones. */
5375 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5378 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5380 if (p
->p_type
== PT_PHDR
)
5381 relocation
= phdr_memaddr
- p
->p_vaddr
;
5385 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5387 if (p
->p_type
== PT_PHDR
)
5388 relocation
= phdr_memaddr
- p
->p_vaddr
;
5391 if (relocation
== -1)
5393 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5394 any real world executables, including PIE executables, have always
5395 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5396 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5397 or present DT_DEBUG anyway (fpc binaries are statically linked).
5399 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5401 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5406 for (i
= 0; i
< num_phdr
; i
++)
5410 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5412 if (p
->p_type
== PT_DYNAMIC
)
5413 return p
->p_vaddr
+ relocation
;
5417 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5419 if (p
->p_type
== PT_DYNAMIC
)
5420 return p
->p_vaddr
+ relocation
;
5427 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5428 can be 0 if the inferior does not yet have the library list initialized.
5429 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
5430 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
5433 get_r_debug (const int pid
, const int is_elf64
)
5435 CORE_ADDR dynamic_memaddr
;
5436 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5437 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5440 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5441 if (dynamic_memaddr
== 0)
5444 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5448 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5452 unsigned char buf
[sizeof (Elf64_Xword
)];
5456 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5458 if (linux_read_memory (dyn
->d_un
.d_val
,
5459 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5465 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5466 map
= dyn
->d_un
.d_val
;
5468 if (dyn
->d_tag
== DT_NULL
)
5473 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5477 unsigned char buf
[sizeof (Elf32_Word
)];
5481 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5483 if (linux_read_memory (dyn
->d_un
.d_val
,
5484 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5490 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5491 map
= dyn
->d_un
.d_val
;
5493 if (dyn
->d_tag
== DT_NULL
)
5497 dynamic_memaddr
+= dyn_size
;
5503 /* Read one pointer from MEMADDR in the inferior. */
5506 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5510 /* Go through a union so this works on either big or little endian
5511 hosts, when the inferior's pointer size is smaller than the size
5512 of CORE_ADDR. It is assumed the inferior's endianness is the
5513 same of the superior's. */
5516 CORE_ADDR core_addr
;
5521 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
5524 if (ptr_size
== sizeof (CORE_ADDR
))
5525 *ptr
= addr
.core_addr
;
5526 else if (ptr_size
== sizeof (unsigned int))
5529 gdb_assert_not_reached ("unhandled pointer size");
5534 struct link_map_offsets
5536 /* Offset and size of r_debug.r_version. */
5537 int r_version_offset
;
5539 /* Offset and size of r_debug.r_map. */
5542 /* Offset to l_addr field in struct link_map. */
5545 /* Offset to l_name field in struct link_map. */
5548 /* Offset to l_ld field in struct link_map. */
5551 /* Offset to l_next field in struct link_map. */
5554 /* Offset to l_prev field in struct link_map. */
5558 /* Construct qXfer:libraries-svr4:read reply. */
5561 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5562 unsigned const char *writebuf
,
5563 CORE_ADDR offset
, int len
)
5566 unsigned document_len
;
5567 struct process_info_private
*const priv
= current_process ()->private;
5568 char filename
[PATH_MAX
];
5571 static const struct link_map_offsets lmo_32bit_offsets
=
5573 0, /* r_version offset. */
5574 4, /* r_debug.r_map offset. */
5575 0, /* l_addr offset in link_map. */
5576 4, /* l_name offset in link_map. */
5577 8, /* l_ld offset in link_map. */
5578 12, /* l_next offset in link_map. */
5579 16 /* l_prev offset in link_map. */
5582 static const struct link_map_offsets lmo_64bit_offsets
=
5584 0, /* r_version offset. */
5585 8, /* r_debug.r_map offset. */
5586 0, /* l_addr offset in link_map. */
5587 8, /* l_name offset in link_map. */
5588 16, /* l_ld offset in link_map. */
5589 24, /* l_next offset in link_map. */
5590 32 /* l_prev offset in link_map. */
5592 const struct link_map_offsets
*lmo
;
5593 unsigned int machine
;
5595 if (writebuf
!= NULL
)
5597 if (readbuf
== NULL
)
5600 pid
= lwpid_of (get_thread_lwp (current_inferior
));
5601 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5602 is_elf64
= elf_64_file_p (filename
, &machine
);
5603 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5605 if (priv
->r_debug
== 0)
5606 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5608 if (priv
->r_debug
== (CORE_ADDR
) -1 || priv
->r_debug
== 0)
5610 document
= xstrdup ("<library-list-svr4 version=\"1.0\"/>\n");
5614 int allocated
= 1024;
5616 const int ptr_size
= is_elf64
? 8 : 4;
5617 CORE_ADDR lm_addr
, lm_prev
, l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5618 int r_version
, header_done
= 0;
5620 document
= xmalloc (allocated
);
5621 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5622 p
= document
+ strlen (document
);
5625 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5626 (unsigned char *) &r_version
,
5627 sizeof (r_version
)) != 0
5630 warning ("unexpected r_debug version %d", r_version
);
5634 if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5635 &lm_addr
, ptr_size
) != 0)
5637 warning ("unable to read r_map from 0x%lx",
5638 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5643 while (read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5644 &l_name
, ptr_size
) == 0
5645 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5646 &l_addr
, ptr_size
) == 0
5647 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5648 &l_ld
, ptr_size
) == 0
5649 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5650 &l_prev
, ptr_size
) == 0
5651 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5652 &l_next
, ptr_size
) == 0)
5654 unsigned char libname
[PATH_MAX
];
5656 if (lm_prev
!= l_prev
)
5658 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5659 (long) lm_prev
, (long) l_prev
);
5663 /* Not checking for error because reading may stop before
5664 we've got PATH_MAX worth of characters. */
5666 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5667 libname
[sizeof (libname
) - 1] = '\0';
5668 if (libname
[0] != '\0')
5670 /* 6x the size for xml_escape_text below. */
5671 size_t len
= 6 * strlen ((char *) libname
);
5676 /* Terminate `<library-list-svr4'. */
5681 while (allocated
< p
- document
+ len
+ 200)
5683 /* Expand to guarantee sufficient storage. */
5684 uintptr_t document_len
= p
- document
;
5686 document
= xrealloc (document
, 2 * allocated
);
5688 p
= document
+ document_len
;
5691 name
= xml_escape_text ((char *) libname
);
5692 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
5693 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5694 name
, (unsigned long) lm_addr
,
5695 (unsigned long) l_addr
, (unsigned long) l_ld
);
5698 else if (lm_prev
== 0)
5700 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5713 /* Empty list; terminate `<library-list-svr4'. */
5717 strcpy (p
, "</library-list-svr4>");
5720 document_len
= strlen (document
);
5721 if (offset
< document_len
)
5722 document_len
-= offset
;
5725 if (len
> document_len
)
5728 memcpy (readbuf
, document
+ offset
, len
);
5734 static struct target_ops linux_target_ops
= {
5735 linux_create_inferior
,
5744 linux_fetch_registers
,
5745 linux_store_registers
,
5746 linux_prepare_to_access_memory
,
5747 linux_done_accessing_memory
,
5750 linux_look_up_symbols
,
5751 linux_request_interrupt
,
5755 linux_stopped_by_watchpoint
,
5756 linux_stopped_data_address
,
5757 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
5762 #ifdef USE_THREAD_DB
5763 thread_db_get_tls_address
,
5768 hostio_last_error_from_errno
,
5771 linux_supports_non_stop
,
5773 linux_start_non_stop
,
5774 linux_supports_multi_process
,
5775 #ifdef USE_THREAD_DB
5776 thread_db_handle_monitor_command
,
5780 linux_common_core_of_thread
,
5782 linux_process_qsupported
,
5783 linux_supports_tracepoints
,
5786 linux_thread_stopped
,
5790 linux_cancel_breakpoints
,
5791 linux_stabilize_threads
,
5792 linux_install_fast_tracepoint_jump_pad
,
5794 linux_supports_disable_randomization
,
5795 linux_get_min_fast_tracepoint_insn_len
,
5796 linux_qxfer_libraries_svr4
,
5797 linux_supports_agent
,
5801 linux_init_signals ()
5803 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5804 to find what the cancel signal actually is. */
5805 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
5806 signal (__SIGRTMIN
+1, SIG_IGN
);
5811 initialize_low (void)
5813 struct sigaction sigchld_action
;
5814 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
5815 set_target_ops (&linux_target_ops
);
5816 set_breakpoint_data (the_low_target
.breakpoint
,
5817 the_low_target
.breakpoint_len
);
5818 linux_init_signals ();
5819 linux_test_for_tracefork ();
5820 #ifdef HAVE_LINUX_REGSETS
5821 for (num_regsets
= 0; target_regsets
[num_regsets
].size
>= 0; num_regsets
++)
5823 disabled_regsets
= xmalloc (num_regsets
);
5826 sigchld_action
.sa_handler
= sigchld_handler
;
5827 sigemptyset (&sigchld_action
.sa_mask
);
5828 sigchld_action
.sa_flags
= SA_RESTART
;
5829 sigaction (SIGCHLD
, &sigchld_action
, NULL
);