1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2013 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "linux-osdata.h"
24 #include "nat/linux-nat.h"
25 #include "nat/linux-waitpid.h"
28 #include <sys/ptrace.h>
29 #include "linux-ptrace.h"
30 #include "linux-procfs.h"
32 #include <sys/ioctl.h>
38 #include <sys/syscall.h>
42 #include <sys/types.h>
47 #include "filestuff.h"
48 #include "tracepoint.h"
50 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
51 then ELFMAG0 will have been defined. If it didn't get included by
52 gdb_proc_service.h then including it will likely introduce a duplicate
53 definition of elf_fpregset_t. */
58 #define SPUFS_MAGIC 0x23c9b64e
61 #ifdef HAVE_PERSONALITY
62 # include <sys/personality.h>
63 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
64 # define ADDR_NO_RANDOMIZE 0x0040000
73 #define W_STOPCODE(sig) ((sig) << 8 | 0x7f)
76 /* This is the kernel's hard limit. Not to be confused with
82 /* Some targets did not define these ptrace constants from the start,
83 so gdbserver defines them locally here. In the future, these may
84 be removed after they are added to asm/ptrace.h. */
85 #if !(defined(PT_TEXT_ADDR) \
86 || defined(PT_DATA_ADDR) \
87 || defined(PT_TEXT_END_ADDR))
88 #if defined(__mcoldfire__)
89 /* These are still undefined in 3.10 kernels. */
90 #define PT_TEXT_ADDR 49*4
91 #define PT_DATA_ADDR 50*4
92 #define PT_TEXT_END_ADDR 51*4
93 /* BFIN already defines these since at least 2.6.32 kernels. */
95 #define PT_TEXT_ADDR 220
96 #define PT_TEXT_END_ADDR 224
97 #define PT_DATA_ADDR 228
98 /* These are still undefined in 3.10 kernels. */
99 #elif defined(__TMS320C6X__)
100 #define PT_TEXT_ADDR (0x10000*4)
101 #define PT_DATA_ADDR (0x10004*4)
102 #define PT_TEXT_END_ADDR (0x10008*4)
106 #ifdef HAVE_LINUX_BTRACE
107 # include "linux-btrace.h"
110 #ifndef HAVE_ELF32_AUXV_T
111 /* Copied from glibc's elf.h. */
114 uint32_t a_type
; /* Entry type */
117 uint32_t a_val
; /* Integer value */
118 /* We use to have pointer elements added here. We cannot do that,
119 though, since it does not work when using 32-bit definitions
120 on 64-bit platforms and vice versa. */
125 #ifndef HAVE_ELF64_AUXV_T
126 /* Copied from glibc's elf.h. */
129 uint64_t a_type
; /* Entry type */
132 uint64_t a_val
; /* Integer value */
133 /* We use to have pointer elements added here. We cannot do that,
134 though, since it does not work when using 32-bit definitions
135 on 64-bit platforms and vice versa. */
140 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
141 representation of the thread ID.
143 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
144 the same as the LWP ID.
146 ``all_processes'' is keyed by the "overall process ID", which
147 GNU/Linux calls tgid, "thread group ID". */
149 struct inferior_list all_lwps
;
151 /* A list of all unknown processes which receive stop signals. Some
152 other process will presumably claim each of these as forked
153 children momentarily. */
155 struct simple_pid_list
157 /* The process ID. */
160 /* The status as reported by waitpid. */
164 struct simple_pid_list
*next
;
166 struct simple_pid_list
*stopped_pids
;
168 /* Trivial list manipulation functions to keep track of a list of new
169 stopped processes. */
172 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
174 struct simple_pid_list
*new_pid
= xmalloc (sizeof (struct simple_pid_list
));
177 new_pid
->status
= status
;
178 new_pid
->next
= *listp
;
183 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
185 struct simple_pid_list
**p
;
187 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
188 if ((*p
)->pid
== pid
)
190 struct simple_pid_list
*next
= (*p
)->next
;
192 *statusp
= (*p
)->status
;
200 enum stopping_threads_kind
202 /* Not stopping threads presently. */
203 NOT_STOPPING_THREADS
,
205 /* Stopping threads. */
208 /* Stopping and suspending threads. */
209 STOPPING_AND_SUSPENDING_THREADS
212 /* This is set while stop_all_lwps is in effect. */
213 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
215 /* FIXME make into a target method? */
216 int using_threads
= 1;
218 /* True if we're presently stabilizing threads (moving them out of
220 static int stabilizing_threads
;
222 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
223 int step
, int signal
, siginfo_t
*info
);
224 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
225 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
226 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
227 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
228 static void *add_lwp (ptid_t ptid
);
229 static int linux_stopped_by_watchpoint (void);
230 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
231 static void proceed_all_lwps (void);
232 static int finish_step_over (struct lwp_info
*lwp
);
233 static CORE_ADDR
get_stop_pc (struct lwp_info
*lwp
);
234 static int kill_lwp (unsigned long lwpid
, int signo
);
236 /* True if the low target can hardware single-step. Such targets
237 don't need a BREAKPOINT_REINSERT_ADDR callback. */
240 can_hardware_single_step (void)
242 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
245 /* True if the low target supports memory breakpoints. If so, we'll
246 have a GET_PC implementation. */
249 supports_breakpoints (void)
251 return (the_low_target
.get_pc
!= NULL
);
254 /* Returns true if this target can support fast tracepoints. This
255 does not mean that the in-process agent has been loaded in the
259 supports_fast_tracepoints (void)
261 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
264 /* True if LWP is stopped in its stepping range. */
267 lwp_in_step_range (struct lwp_info
*lwp
)
269 CORE_ADDR pc
= lwp
->stop_pc
;
271 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
274 struct pending_signals
278 struct pending_signals
*prev
;
281 /* The read/write ends of the pipe registered as waitable file in the
283 static int linux_event_pipe
[2] = { -1, -1 };
285 /* True if we're currently in async mode. */
286 #define target_is_async_p() (linux_event_pipe[0] != -1)
288 static void send_sigstop (struct lwp_info
*lwp
);
289 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
291 /* Return non-zero if HEADER is a 64-bit ELF file. */
294 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
296 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
297 && header
->e_ident
[EI_MAG1
] == ELFMAG1
298 && header
->e_ident
[EI_MAG2
] == ELFMAG2
299 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
301 *machine
= header
->e_machine
;
302 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
309 /* Return non-zero if FILE is a 64-bit ELF file,
310 zero if the file is not a 64-bit ELF file,
311 and -1 if the file is not accessible or doesn't exist. */
314 elf_64_file_p (const char *file
, unsigned int *machine
)
319 fd
= open (file
, O_RDONLY
);
323 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
330 return elf_64_header_p (&header
, machine
);
333 /* Accepts an integer PID; Returns true if the executable PID is
334 running is a 64-bit ELF file.. */
337 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
341 sprintf (file
, "/proc/%d/exe", pid
);
342 return elf_64_file_p (file
, machine
);
346 delete_lwp (struct lwp_info
*lwp
)
348 remove_thread (get_lwp_thread (lwp
));
349 remove_inferior (&all_lwps
, &lwp
->head
);
350 free (lwp
->arch_private
);
354 /* Add a process to the common process list, and set its private
357 static struct process_info
*
358 linux_add_process (int pid
, int attached
)
360 struct process_info
*proc
;
362 proc
= add_process (pid
, attached
);
363 proc
->private = xcalloc (1, sizeof (*proc
->private));
365 /* Set the arch when the first LWP stops. */
366 proc
->private->new_inferior
= 1;
368 if (the_low_target
.new_process
!= NULL
)
369 proc
->private->arch_private
= the_low_target
.new_process ();
374 /* Handle a GNU/Linux extended wait response. If we see a clone
375 event, we need to add the new LWP to our list (and not report the
376 trap to higher layers). */
379 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
381 int event
= wstat
>> 16;
382 struct lwp_info
*new_lwp
;
384 if (event
== PTRACE_EVENT_CLONE
)
387 unsigned long new_pid
;
390 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), (PTRACE_TYPE_ARG3
) 0,
393 /* If we haven't already seen the new PID stop, wait for it now. */
394 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
396 /* The new child has a pending SIGSTOP. We can't affect it until it
397 hits the SIGSTOP, but we're already attached. */
399 ret
= my_waitpid (new_pid
, &status
, __WALL
);
402 perror_with_name ("waiting for new child");
403 else if (ret
!= new_pid
)
404 warning ("wait returned unexpected PID %d", ret
);
405 else if (!WIFSTOPPED (status
))
406 warning ("wait returned unexpected status 0x%x", status
);
409 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
410 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
411 add_thread (ptid
, new_lwp
);
413 /* Either we're going to immediately resume the new thread
414 or leave it stopped. linux_resume_one_lwp is a nop if it
415 thinks the thread is currently running, so set this first
416 before calling linux_resume_one_lwp. */
417 new_lwp
->stopped
= 1;
419 /* If we're suspending all threads, leave this one suspended
421 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
422 new_lwp
->suspended
= 1;
424 /* Normally we will get the pending SIGSTOP. But in some cases
425 we might get another signal delivered to the group first.
426 If we do get another signal, be sure not to lose it. */
427 if (WSTOPSIG (status
) == SIGSTOP
)
429 if (stopping_threads
!= NOT_STOPPING_THREADS
)
430 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
432 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
436 new_lwp
->stop_expected
= 1;
438 if (stopping_threads
!= NOT_STOPPING_THREADS
)
440 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
441 new_lwp
->status_pending_p
= 1;
442 new_lwp
->status_pending
= status
;
445 /* Pass the signal on. This is what GDB does - except
446 shouldn't we really report it instead? */
447 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
450 /* Always resume the current thread. If we are stopping
451 threads, it will have a pending SIGSTOP; we may as well
453 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
457 /* Return the PC as read from the regcache of LWP, without any
461 get_pc (struct lwp_info
*lwp
)
463 struct thread_info
*saved_inferior
;
464 struct regcache
*regcache
;
467 if (the_low_target
.get_pc
== NULL
)
470 saved_inferior
= current_inferior
;
471 current_inferior
= get_lwp_thread (lwp
);
473 regcache
= get_thread_regcache (current_inferior
, 1);
474 pc
= (*the_low_target
.get_pc
) (regcache
);
477 fprintf (stderr
, "pc is 0x%lx\n", (long) pc
);
479 current_inferior
= saved_inferior
;
483 /* This function should only be called if LWP got a SIGTRAP.
484 The SIGTRAP could mean several things.
486 On i386, where decr_pc_after_break is non-zero:
487 If we were single-stepping this process using PTRACE_SINGLESTEP,
488 we will get only the one SIGTRAP (even if the instruction we
489 stepped over was a breakpoint). The value of $eip will be the
491 If we continue the process using PTRACE_CONT, we will get a
492 SIGTRAP when we hit a breakpoint. The value of $eip will be
493 the instruction after the breakpoint (i.e. needs to be
494 decremented). If we report the SIGTRAP to GDB, we must also
495 report the undecremented PC. If we cancel the SIGTRAP, we
496 must resume at the decremented PC.
498 (Presumably, not yet tested) On a non-decr_pc_after_break machine
499 with hardware or kernel single-step:
500 If we single-step over a breakpoint instruction, our PC will
501 point at the following instruction. If we continue and hit a
502 breakpoint instruction, our PC will point at the breakpoint
506 get_stop_pc (struct lwp_info
*lwp
)
510 if (the_low_target
.get_pc
== NULL
)
513 stop_pc
= get_pc (lwp
);
515 if (WSTOPSIG (lwp
->last_status
) == SIGTRAP
517 && !lwp
->stopped_by_watchpoint
518 && lwp
->last_status
>> 16 == 0)
519 stop_pc
-= the_low_target
.decr_pc_after_break
;
522 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
528 add_lwp (ptid_t ptid
)
530 struct lwp_info
*lwp
;
532 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
533 memset (lwp
, 0, sizeof (*lwp
));
537 if (the_low_target
.new_thread
!= NULL
)
538 lwp
->arch_private
= the_low_target
.new_thread ();
540 add_inferior_to_list (&all_lwps
, &lwp
->head
);
545 /* Start an inferior process and returns its pid.
546 ALLARGS is a vector of program-name and args. */
549 linux_create_inferior (char *program
, char **allargs
)
551 #ifdef HAVE_PERSONALITY
552 int personality_orig
= 0, personality_set
= 0;
554 struct lwp_info
*new_lwp
;
558 #ifdef HAVE_PERSONALITY
559 if (disable_randomization
)
562 personality_orig
= personality (0xffffffff);
563 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
566 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
568 if (errno
!= 0 || (personality_set
569 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
570 warning ("Error disabling address space randomization: %s",
575 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
581 perror_with_name ("fork");
586 ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
588 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
589 signal (__SIGRTMIN
+ 1, SIG_DFL
);
594 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
595 stdout to stderr so that inferior i/o doesn't corrupt the connection.
596 Also, redirect stdin to /dev/null. */
597 if (remote_connection_is_stdio ())
600 open ("/dev/null", O_RDONLY
);
602 if (write (2, "stdin/stdout redirected\n",
603 sizeof ("stdin/stdout redirected\n") - 1) < 0)
605 /* Errors ignored. */;
609 execv (program
, allargs
);
611 execvp (program
, allargs
);
613 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
619 #ifdef HAVE_PERSONALITY
623 personality (personality_orig
);
625 warning ("Error restoring address space randomization: %s",
630 linux_add_process (pid
, 0);
632 ptid
= ptid_build (pid
, pid
, 0);
633 new_lwp
= add_lwp (ptid
);
634 add_thread (ptid
, new_lwp
);
635 new_lwp
->must_set_ptrace_flags
= 1;
640 /* Attach to an inferior process. */
643 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
646 struct lwp_info
*new_lwp
;
648 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
651 struct buffer buffer
;
655 /* If we fail to attach to an LWP, just warn. */
656 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
657 strerror (errno
), errno
);
662 /* If we fail to attach to a process, report an error. */
663 buffer_init (&buffer
);
664 linux_ptrace_attach_warnings (lwpid
, &buffer
);
665 buffer_grow_str0 (&buffer
, "");
666 error ("%sCannot attach to lwp %ld: %s (%d)", buffer_finish (&buffer
),
667 lwpid
, strerror (errno
), errno
);
671 /* If lwp is the tgid, we handle adding existing threads later.
672 Otherwise we just add lwp without bothering about any other
674 ptid
= ptid_build (lwpid
, lwpid
, 0);
677 /* Note that extracting the pid from the current inferior is
678 safe, since we're always called in the context of the same
679 process as this new thread. */
680 int pid
= pid_of (get_thread_lwp (current_inferior
));
681 ptid
= ptid_build (pid
, lwpid
, 0);
684 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
685 add_thread (ptid
, new_lwp
);
687 /* We need to wait for SIGSTOP before being able to make the next
688 ptrace call on this LWP. */
689 new_lwp
->must_set_ptrace_flags
= 1;
691 if (linux_proc_pid_is_stopped (lwpid
))
695 "Attached to a stopped process\n");
697 /* The process is definitely stopped. It is in a job control
698 stop, unless the kernel predates the TASK_STOPPED /
699 TASK_TRACED distinction, in which case it might be in a
700 ptrace stop. Make sure it is in a ptrace stop; from there we
701 can kill it, signal it, et cetera.
703 First make sure there is a pending SIGSTOP. Since we are
704 already attached, the process can not transition from stopped
705 to running without a PTRACE_CONT; so we know this signal will
706 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
707 probably already in the queue (unless this kernel is old
708 enough to use TASK_STOPPED for ptrace stops); but since
709 SIGSTOP is not an RT signal, it can only be queued once. */
710 kill_lwp (lwpid
, SIGSTOP
);
712 /* Finally, resume the stopped process. This will deliver the
713 SIGSTOP (or a higher priority signal, just like normal
714 PTRACE_ATTACH), which we'll catch later on. */
715 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
718 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
721 There are several cases to consider here:
723 1) gdbserver has already attached to the process and is being notified
724 of a new thread that is being created.
725 In this case we should ignore that SIGSTOP and resume the
726 process. This is handled below by setting stop_expected = 1,
727 and the fact that add_thread sets last_resume_kind ==
730 2) This is the first thread (the process thread), and we're attaching
731 to it via attach_inferior.
732 In this case we want the process thread to stop.
733 This is handled by having linux_attach set last_resume_kind ==
734 resume_stop after we return.
736 If the pid we are attaching to is also the tgid, we attach to and
737 stop all the existing threads. Otherwise, we attach to pid and
738 ignore any other threads in the same group as this pid.
740 3) GDB is connecting to gdbserver and is requesting an enumeration of all
742 In this case we want the thread to stop.
743 FIXME: This case is currently not properly handled.
744 We should wait for the SIGSTOP but don't. Things work apparently
745 because enough time passes between when we ptrace (ATTACH) and when
746 gdb makes the next ptrace call on the thread.
748 On the other hand, if we are currently trying to stop all threads, we
749 should treat the new thread as if we had sent it a SIGSTOP. This works
750 because we are guaranteed that the add_lwp call above added us to the
751 end of the list, and so the new thread has not yet reached
752 wait_for_sigstop (but will). */
753 new_lwp
->stop_expected
= 1;
757 linux_attach_lwp (unsigned long lwpid
)
759 linux_attach_lwp_1 (lwpid
, 0);
762 /* Attach to PID. If PID is the tgid, attach to it and all
766 linux_attach (unsigned long pid
)
768 /* Attach to PID. We will check for other threads
770 linux_attach_lwp_1 (pid
, 1);
771 linux_add_process (pid
, 1);
775 struct thread_info
*thread
;
777 /* Don't ignore the initial SIGSTOP if we just attached to this
778 process. It will be collected by wait shortly. */
779 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
780 thread
->last_resume_kind
= resume_stop
;
783 if (linux_proc_get_tgid (pid
) == pid
)
788 sprintf (pathname
, "/proc/%ld/task", pid
);
790 dir
= opendir (pathname
);
794 fprintf (stderr
, "Could not open /proc/%ld/task.\n", pid
);
799 /* At this point we attached to the tgid. Scan the task for
802 int new_threads_found
;
806 while (iterations
< 2)
808 new_threads_found
= 0;
809 /* Add all the other threads. While we go through the
810 threads, new threads may be spawned. Cycle through
811 the list of threads until we have done two iterations without
812 finding new threads. */
813 while ((dp
= readdir (dir
)) != NULL
)
816 lwp
= strtoul (dp
->d_name
, NULL
, 10);
818 /* Is this a new thread? */
820 && find_thread_ptid (ptid_build (pid
, lwp
, 0)) == NULL
)
822 linux_attach_lwp_1 (lwp
, 0);
827 Found and attached to new lwp %ld\n", lwp
);
831 if (!new_threads_found
)
852 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
854 struct counter
*counter
= args
;
856 if (ptid_get_pid (entry
->id
) == counter
->pid
)
858 if (++counter
->count
> 1)
866 last_thread_of_process_p (struct thread_info
*thread
)
868 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
869 int pid
= ptid_get_pid (ptid
);
870 struct counter counter
= { pid
, 0 };
872 return (find_inferior (&all_threads
,
873 second_thread_of_pid_p
, &counter
) == NULL
);
879 linux_kill_one_lwp (struct lwp_info
*lwp
)
881 int pid
= lwpid_of (lwp
);
883 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
884 there is no signal context, and ptrace(PTRACE_KILL) (or
885 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
886 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
887 alternative is to kill with SIGKILL. We only need one SIGKILL
888 per process, not one for each thread. But since we still support
889 linuxthreads, and we also support debugging programs using raw
890 clone without CLONE_THREAD, we send one for each thread. For
891 years, we used PTRACE_KILL only, so we're being a bit paranoid
892 about some old kernels where PTRACE_KILL might work better
893 (dubious if there are any such, but that's why it's paranoia), so
894 we try SIGKILL first, PTRACE_KILL second, and so we're fine
901 "LKL: kill (SIGKILL) %s, 0, 0 (%s)\n",
902 target_pid_to_str (ptid_of (lwp
)),
903 errno
? strerror (errno
) : "OK");
906 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
909 "LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
910 target_pid_to_str (ptid_of (lwp
)),
911 errno
? strerror (errno
) : "OK");
914 /* Callback for `find_inferior'. Kills an lwp of a given process,
915 except the leader. */
918 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
920 struct thread_info
*thread
= (struct thread_info
*) entry
;
921 struct lwp_info
*lwp
= get_thread_lwp (thread
);
923 int pid
= * (int *) args
;
925 if (ptid_get_pid (entry
->id
) != pid
)
928 /* We avoid killing the first thread here, because of a Linux kernel (at
929 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
930 the children get a chance to be reaped, it will remain a zombie
933 if (lwpid_of (lwp
) == pid
)
936 fprintf (stderr
, "lkop: is last of process %s\n",
937 target_pid_to_str (entry
->id
));
943 linux_kill_one_lwp (lwp
);
945 /* Make sure it died. The loop is most likely unnecessary. */
946 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
947 } while (pid
> 0 && WIFSTOPPED (wstat
));
955 struct process_info
*process
;
956 struct lwp_info
*lwp
;
960 process
= find_process_pid (pid
);
964 /* If we're killing a running inferior, make sure it is stopped
965 first, as PTRACE_KILL will not work otherwise. */
966 stop_all_lwps (0, NULL
);
968 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
970 /* See the comment in linux_kill_one_lwp. We did not kill the first
971 thread in the list, so do so now. */
972 lwp
= find_lwp_pid (pid_to_ptid (pid
));
977 fprintf (stderr
, "lk_1: cannot find lwp %ld, for pid: %d\n",
978 lwpid_of (lwp
), pid
);
983 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
984 lwpid_of (lwp
), pid
);
988 linux_kill_one_lwp (lwp
);
990 /* Make sure it died. The loop is most likely unnecessary. */
991 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
992 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
995 the_target
->mourn (process
);
997 /* Since we presently can only stop all lwps of all processes, we
998 need to unstop lwps of other processes. */
999 unstop_all_lwps (0, NULL
);
1003 /* Get pending signal of THREAD, for detaching purposes. This is the
1004 signal the thread last stopped for, which we need to deliver to the
1005 thread when detaching, otherwise, it'd be suppressed/lost. */
1008 get_detach_signal (struct thread_info
*thread
)
1010 enum gdb_signal signo
= GDB_SIGNAL_0
;
1012 struct lwp_info
*lp
= get_thread_lwp (thread
);
1014 if (lp
->status_pending_p
)
1015 status
= lp
->status_pending
;
1018 /* If the thread had been suspended by gdbserver, and it stopped
1019 cleanly, then it'll have stopped with SIGSTOP. But we don't
1020 want to deliver that SIGSTOP. */
1021 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1022 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1025 /* Otherwise, we may need to deliver the signal we
1027 status
= lp
->last_status
;
1030 if (!WIFSTOPPED (status
))
1034 "GPS: lwp %s hasn't stopped: no pending signal\n",
1035 target_pid_to_str (ptid_of (lp
)));
1039 /* Extended wait statuses aren't real SIGTRAPs. */
1040 if (WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
1044 "GPS: lwp %s had stopped with extended "
1045 "status: no pending signal\n",
1046 target_pid_to_str (ptid_of (lp
)));
1050 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1052 if (program_signals_p
&& !program_signals
[signo
])
1056 "GPS: lwp %s had signal %s, but it is in nopass state\n",
1057 target_pid_to_str (ptid_of (lp
)),
1058 gdb_signal_to_string (signo
));
1061 else if (!program_signals_p
1062 /* If we have no way to know which signals GDB does not
1063 want to have passed to the program, assume
1064 SIGTRAP/SIGINT, which is GDB's default. */
1065 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1069 "GPS: lwp %s had signal %s, "
1070 "but we don't know if we should pass it. Default to not.\n",
1071 target_pid_to_str (ptid_of (lp
)),
1072 gdb_signal_to_string (signo
));
1079 "GPS: lwp %s has pending signal %s: delivering it.\n",
1080 target_pid_to_str (ptid_of (lp
)),
1081 gdb_signal_to_string (signo
));
1083 return WSTOPSIG (status
);
1088 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1090 struct thread_info
*thread
= (struct thread_info
*) entry
;
1091 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1092 int pid
= * (int *) args
;
1095 if (ptid_get_pid (entry
->id
) != pid
)
1098 /* If there is a pending SIGSTOP, get rid of it. */
1099 if (lwp
->stop_expected
)
1103 "Sending SIGCONT to %s\n",
1104 target_pid_to_str (ptid_of (lwp
)));
1106 kill_lwp (lwpid_of (lwp
), SIGCONT
);
1107 lwp
->stop_expected
= 0;
1110 /* Flush any pending changes to the process's registers. */
1111 regcache_invalidate_thread (get_lwp_thread (lwp
));
1113 /* Pass on any pending signal for this thread. */
1114 sig
= get_detach_signal (thread
);
1116 /* Finally, let it resume. */
1117 if (the_low_target
.prepare_to_resume
!= NULL
)
1118 the_low_target
.prepare_to_resume (lwp
);
1119 if (ptrace (PTRACE_DETACH
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
1120 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1121 error (_("Can't detach %s: %s"),
1122 target_pid_to_str (ptid_of (lwp
)),
1130 linux_detach (int pid
)
1132 struct process_info
*process
;
1134 process
= find_process_pid (pid
);
1135 if (process
== NULL
)
1138 /* Stop all threads before detaching. First, ptrace requires that
1139 the thread is stopped to sucessfully detach. Second, thread_db
1140 may need to uninstall thread event breakpoints from memory, which
1141 only works with a stopped process anyway. */
1142 stop_all_lwps (0, NULL
);
1144 #ifdef USE_THREAD_DB
1145 thread_db_detach (process
);
1148 /* Stabilize threads (move out of jump pads). */
1149 stabilize_threads ();
1151 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1153 the_target
->mourn (process
);
1155 /* Since we presently can only stop all lwps of all processes, we
1156 need to unstop lwps of other processes. */
1157 unstop_all_lwps (0, NULL
);
1161 /* Remove all LWPs that belong to process PROC from the lwp list. */
1164 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1166 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1167 struct process_info
*process
= proc
;
1169 if (pid_of (lwp
) == pid_of (process
))
1176 linux_mourn (struct process_info
*process
)
1178 struct process_info_private
*priv
;
1180 #ifdef USE_THREAD_DB
1181 thread_db_mourn (process
);
1184 find_inferior (&all_lwps
, delete_lwp_callback
, process
);
1186 /* Freeing all private data. */
1187 priv
= process
->private;
1188 free (priv
->arch_private
);
1190 process
->private = NULL
;
1192 remove_process (process
);
1196 linux_join (int pid
)
1201 ret
= my_waitpid (pid
, &status
, 0);
1202 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1204 } while (ret
!= -1 || errno
!= ECHILD
);
1207 /* Return nonzero if the given thread is still alive. */
1209 linux_thread_alive (ptid_t ptid
)
1211 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1213 /* We assume we always know if a thread exits. If a whole process
1214 exited but we still haven't been able to report it to GDB, we'll
1215 hold on to the last lwp of the dead process. */
1222 /* Return 1 if this lwp has an interesting status pending. */
1224 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1226 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1227 ptid_t ptid
= * (ptid_t
*) arg
;
1228 struct thread_info
*thread
;
1230 /* Check if we're only interested in events from a specific process
1232 if (!ptid_equal (minus_one_ptid
, ptid
)
1233 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
1236 thread
= get_lwp_thread (lwp
);
1238 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1239 report any status pending the LWP may have. */
1240 if (thread
->last_resume_kind
== resume_stop
1241 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1244 return lwp
->status_pending_p
;
1248 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1250 ptid_t ptid
= *(ptid_t
*) data
;
1253 if (ptid_get_lwp (ptid
) != 0)
1254 lwp
= ptid_get_lwp (ptid
);
1256 lwp
= ptid_get_pid (ptid
);
1258 if (ptid_get_lwp (entry
->id
) == lwp
)
1265 find_lwp_pid (ptid_t ptid
)
1267 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
1270 static struct lwp_info
*
1271 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
1274 int to_wait_for
= -1;
1275 struct lwp_info
*child
= NULL
;
1278 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1280 if (ptid_equal (ptid
, minus_one_ptid
))
1281 to_wait_for
= -1; /* any child */
1283 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1289 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1290 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1293 perror_with_name ("waitpid");
1296 && (!WIFSTOPPED (*wstatp
)
1297 || (WSTOPSIG (*wstatp
) != 32
1298 && WSTOPSIG (*wstatp
) != 33)))
1299 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1301 child
= find_lwp_pid (pid_to_ptid (ret
));
1303 /* If we didn't find a process, one of two things presumably happened:
1304 - A process we started and then detached from has exited. Ignore it.
1305 - A process we are controlling has forked and the new child's stop
1306 was reported to us by the kernel. Save its PID. */
1307 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1309 add_to_pid_list (&stopped_pids
, ret
, *wstatp
);
1312 else if (child
== NULL
)
1317 child
->last_status
= *wstatp
;
1319 if (WIFSTOPPED (*wstatp
))
1321 struct process_info
*proc
;
1323 /* Architecture-specific setup after inferior is running. This
1324 needs to happen after we have attached to the inferior and it
1325 is stopped for the first time, but before we access any
1326 inferior registers. */
1327 proc
= find_process_pid (pid_of (child
));
1328 if (proc
->private->new_inferior
)
1330 struct thread_info
*saved_inferior
;
1332 saved_inferior
= current_inferior
;
1333 current_inferior
= get_lwp_thread (child
);
1335 the_low_target
.arch_setup ();
1337 current_inferior
= saved_inferior
;
1339 proc
->private->new_inferior
= 0;
1343 /* Fetch the possibly triggered data watchpoint info and store it in
1346 On some archs, like x86, that use debug registers to set
1347 watchpoints, it's possible that the way to know which watched
1348 address trapped, is to check the register that is used to select
1349 which address to watch. Problem is, between setting the
1350 watchpoint and reading back which data address trapped, the user
1351 may change the set of watchpoints, and, as a consequence, GDB
1352 changes the debug registers in the inferior. To avoid reading
1353 back a stale stopped-data-address when that happens, we cache in
1354 LP the fact that a watchpoint trapped, and the corresponding data
1355 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1356 changes the debug registers meanwhile, we have the cached data we
1359 if (WIFSTOPPED (*wstatp
) && WSTOPSIG (*wstatp
) == SIGTRAP
)
1361 if (the_low_target
.stopped_by_watchpoint
== NULL
)
1363 child
->stopped_by_watchpoint
= 0;
1367 struct thread_info
*saved_inferior
;
1369 saved_inferior
= current_inferior
;
1370 current_inferior
= get_lwp_thread (child
);
1372 child
->stopped_by_watchpoint
1373 = the_low_target
.stopped_by_watchpoint ();
1375 if (child
->stopped_by_watchpoint
)
1377 if (the_low_target
.stopped_data_address
!= NULL
)
1378 child
->stopped_data_address
1379 = the_low_target
.stopped_data_address ();
1381 child
->stopped_data_address
= 0;
1384 current_inferior
= saved_inferior
;
1388 /* Store the STOP_PC, with adjustment applied. This depends on the
1389 architecture being defined already (so that CHILD has a valid
1390 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1392 if (WIFSTOPPED (*wstatp
))
1393 child
->stop_pc
= get_stop_pc (child
);
1396 && WIFSTOPPED (*wstatp
)
1397 && the_low_target
.get_pc
!= NULL
)
1399 struct thread_info
*saved_inferior
= current_inferior
;
1400 struct regcache
*regcache
;
1403 current_inferior
= get_lwp_thread (child
);
1404 regcache
= get_thread_regcache (current_inferior
, 1);
1405 pc
= (*the_low_target
.get_pc
) (regcache
);
1406 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1407 current_inferior
= saved_inferior
;
1413 /* This function should only be called if the LWP got a SIGTRAP.
1415 Handle any tracepoint steps or hits. Return true if a tracepoint
1416 event was handled, 0 otherwise. */
1419 handle_tracepoints (struct lwp_info
*lwp
)
1421 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1422 int tpoint_related_event
= 0;
1424 /* If this tracepoint hit causes a tracing stop, we'll immediately
1425 uninsert tracepoints. To do this, we temporarily pause all
1426 threads, unpatch away, and then unpause threads. We need to make
1427 sure the unpausing doesn't resume LWP too. */
1430 /* And we need to be sure that any all-threads-stopping doesn't try
1431 to move threads out of the jump pads, as it could deadlock the
1432 inferior (LWP could be in the jump pad, maybe even holding the
1435 /* Do any necessary step collect actions. */
1436 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1438 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1440 /* See if we just hit a tracepoint and do its main collect
1442 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1446 gdb_assert (lwp
->suspended
== 0);
1447 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1449 if (tpoint_related_event
)
1452 fprintf (stderr
, "got a tracepoint event\n");
1459 /* Convenience wrapper. Returns true if LWP is presently collecting a
1463 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1464 struct fast_tpoint_collect_status
*status
)
1466 CORE_ADDR thread_area
;
1468 if (the_low_target
.get_thread_area
== NULL
)
1471 /* Get the thread area address. This is used to recognize which
1472 thread is which when tracing with the in-process agent library.
1473 We don't read anything from the address, and treat it as opaque;
1474 it's the address itself that we assume is unique per-thread. */
1475 if ((*the_low_target
.get_thread_area
) (lwpid_of (lwp
), &thread_area
) == -1)
1478 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1481 /* The reason we resume in the caller, is because we want to be able
1482 to pass lwp->status_pending as WSTAT, and we need to clear
1483 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1484 refuses to resume. */
1487 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1489 struct thread_info
*saved_inferior
;
1491 saved_inferior
= current_inferior
;
1492 current_inferior
= get_lwp_thread (lwp
);
1495 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1496 && supports_fast_tracepoints ()
1497 && agent_loaded_p ())
1499 struct fast_tpoint_collect_status status
;
1504 Checking whether LWP %ld needs to move out of the jump pad.\n",
1507 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1510 || (WSTOPSIG (*wstat
) != SIGILL
1511 && WSTOPSIG (*wstat
) != SIGFPE
1512 && WSTOPSIG (*wstat
) != SIGSEGV
1513 && WSTOPSIG (*wstat
) != SIGBUS
))
1515 lwp
->collecting_fast_tracepoint
= r
;
1519 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1521 /* Haven't executed the original instruction yet.
1522 Set breakpoint there, and wait till it's hit,
1523 then single-step until exiting the jump pad. */
1524 lwp
->exit_jump_pad_bkpt
1525 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1530 Checking whether LWP %ld needs to move out of the jump pad...it does\n",
1532 current_inferior
= saved_inferior
;
1539 /* If we get a synchronous signal while collecting, *and*
1540 while executing the (relocated) original instruction,
1541 reset the PC to point at the tpoint address, before
1542 reporting to GDB. Otherwise, it's an IPA lib bug: just
1543 report the signal to GDB, and pray for the best. */
1545 lwp
->collecting_fast_tracepoint
= 0;
1548 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1549 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1552 struct regcache
*regcache
;
1554 /* The si_addr on a few signals references the address
1555 of the faulting instruction. Adjust that as
1557 if ((WSTOPSIG (*wstat
) == SIGILL
1558 || WSTOPSIG (*wstat
) == SIGFPE
1559 || WSTOPSIG (*wstat
) == SIGBUS
1560 || WSTOPSIG (*wstat
) == SIGSEGV
)
1561 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
),
1562 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
1563 /* Final check just to make sure we don't clobber
1564 the siginfo of non-kernel-sent signals. */
1565 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1567 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1568 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
),
1569 (PTRACE_TYPE_ARG3
) 0, &info
);
1572 regcache
= get_thread_regcache (get_lwp_thread (lwp
), 1);
1573 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1574 lwp
->stop_pc
= status
.tpoint_addr
;
1576 /* Cancel any fast tracepoint lock this thread was
1578 force_unlock_trace_buffer ();
1581 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1585 "Cancelling fast exit-jump-pad: removing bkpt. "
1586 "stopping all threads momentarily.\n");
1588 stop_all_lwps (1, lwp
);
1589 cancel_breakpoints ();
1591 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1592 lwp
->exit_jump_pad_bkpt
= NULL
;
1594 unstop_all_lwps (1, lwp
);
1596 gdb_assert (lwp
->suspended
>= 0);
1603 Checking whether LWP %ld needs to move out of the jump pad...no\n",
1606 current_inferior
= saved_inferior
;
1610 /* Enqueue one signal in the "signals to report later when out of the
1614 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1616 struct pending_signals
*p_sig
;
1620 Deferring signal %d for LWP %ld.\n", WSTOPSIG (*wstat
), lwpid_of (lwp
));
1624 struct pending_signals
*sig
;
1626 for (sig
= lwp
->pending_signals_to_report
;
1630 " Already queued %d\n",
1633 fprintf (stderr
, " (no more currently queued signals)\n");
1636 /* Don't enqueue non-RT signals if they are already in the deferred
1637 queue. (SIGSTOP being the easiest signal to see ending up here
1639 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1641 struct pending_signals
*sig
;
1643 for (sig
= lwp
->pending_signals_to_report
;
1647 if (sig
->signal
== WSTOPSIG (*wstat
))
1651 "Not requeuing already queued non-RT signal %d"
1660 p_sig
= xmalloc (sizeof (*p_sig
));
1661 p_sig
->prev
= lwp
->pending_signals_to_report
;
1662 p_sig
->signal
= WSTOPSIG (*wstat
);
1663 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1664 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
1667 lwp
->pending_signals_to_report
= p_sig
;
1670 /* Dequeue one signal from the "signals to report later when out of
1671 the jump pad" list. */
1674 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1676 if (lwp
->pending_signals_to_report
!= NULL
)
1678 struct pending_signals
**p_sig
;
1680 p_sig
= &lwp
->pending_signals_to_report
;
1681 while ((*p_sig
)->prev
!= NULL
)
1682 p_sig
= &(*p_sig
)->prev
;
1684 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1685 if ((*p_sig
)->info
.si_signo
!= 0)
1686 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
1692 fprintf (stderr
, "Reporting deferred signal %d for LWP %ld.\n",
1693 WSTOPSIG (*wstat
), lwpid_of (lwp
));
1697 struct pending_signals
*sig
;
1699 for (sig
= lwp
->pending_signals_to_report
;
1703 " Still queued %d\n",
1706 fprintf (stderr
, " (no more queued signals)\n");
1715 /* Arrange for a breakpoint to be hit again later. We don't keep the
1716 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1717 will handle the current event, eventually we will resume this LWP,
1718 and this breakpoint will trap again. */
1721 cancel_breakpoint (struct lwp_info
*lwp
)
1723 struct thread_info
*saved_inferior
;
1725 /* There's nothing to do if we don't support breakpoints. */
1726 if (!supports_breakpoints ())
1729 /* breakpoint_at reads from current inferior. */
1730 saved_inferior
= current_inferior
;
1731 current_inferior
= get_lwp_thread (lwp
);
1733 if ((*the_low_target
.breakpoint_at
) (lwp
->stop_pc
))
1737 "CB: Push back breakpoint for %s\n",
1738 target_pid_to_str (ptid_of (lwp
)));
1740 /* Back up the PC if necessary. */
1741 if (the_low_target
.decr_pc_after_break
)
1743 struct regcache
*regcache
1744 = get_thread_regcache (current_inferior
, 1);
1745 (*the_low_target
.set_pc
) (regcache
, lwp
->stop_pc
);
1748 current_inferior
= saved_inferior
;
1755 "CB: No breakpoint found at %s for [%s]\n",
1756 paddress (lwp
->stop_pc
),
1757 target_pid_to_str (ptid_of (lwp
)));
1760 current_inferior
= saved_inferior
;
1764 /* When the event-loop is doing a step-over, this points at the thread
1766 ptid_t step_over_bkpt
;
1768 /* Wait for an event from child PID. If PID is -1, wait for any
1769 child. Store the stop status through the status pointer WSTAT.
1770 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1771 event was found and OPTIONS contains WNOHANG. Return the PID of
1772 the stopped child otherwise. */
1775 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1777 struct lwp_info
*event_child
, *requested_child
;
1781 requested_child
= NULL
;
1783 /* Check for a lwp with a pending status. */
1785 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
1787 event_child
= (struct lwp_info
*)
1788 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1789 if (debug_threads
&& event_child
)
1790 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1794 requested_child
= find_lwp_pid (ptid
);
1796 if (stopping_threads
== NOT_STOPPING_THREADS
1797 && requested_child
->status_pending_p
1798 && requested_child
->collecting_fast_tracepoint
)
1800 enqueue_one_deferred_signal (requested_child
,
1801 &requested_child
->status_pending
);
1802 requested_child
->status_pending_p
= 0;
1803 requested_child
->status_pending
= 0;
1804 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
1807 if (requested_child
->suspended
1808 && requested_child
->status_pending_p
)
1809 fatal ("requesting an event out of a suspended child?");
1811 if (requested_child
->status_pending_p
)
1812 event_child
= requested_child
;
1815 if (event_child
!= NULL
)
1818 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1819 lwpid_of (event_child
), event_child
->status_pending
);
1820 *wstat
= event_child
->status_pending
;
1821 event_child
->status_pending_p
= 0;
1822 event_child
->status_pending
= 0;
1823 current_inferior
= get_lwp_thread (event_child
);
1824 return lwpid_of (event_child
);
1827 if (ptid_is_pid (ptid
))
1829 /* A request to wait for a specific tgid. This is not possible
1830 with waitpid, so instead, we wait for any child, and leave
1831 children we're not interested in right now with a pending
1832 status to report later. */
1833 wait_ptid
= minus_one_ptid
;
1838 /* We only enter this loop if no process has a pending wait status. Thus
1839 any action taken in response to a wait status inside this loop is
1840 responding as soon as we detect the status, not after any pending
1844 event_child
= linux_wait_for_lwp (wait_ptid
, wstat
, options
);
1846 if ((options
& WNOHANG
) && event_child
== NULL
)
1849 fprintf (stderr
, "WNOHANG set, no event found\n");
1853 if (event_child
== NULL
)
1854 error ("event from unknown child");
1856 if (ptid_is_pid (ptid
)
1857 && ptid_get_pid (ptid
) != ptid_get_pid (ptid_of (event_child
)))
1859 if (! WIFSTOPPED (*wstat
))
1860 mark_lwp_dead (event_child
, *wstat
);
1863 event_child
->status_pending_p
= 1;
1864 event_child
->status_pending
= *wstat
;
1869 current_inferior
= get_lwp_thread (event_child
);
1871 /* Check for thread exit. */
1872 if (! WIFSTOPPED (*wstat
))
1875 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1877 /* If the last thread is exiting, just return. */
1878 if (last_thread_of_process_p (current_inferior
))
1881 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1882 lwpid_of (event_child
));
1883 return lwpid_of (event_child
);
1888 current_inferior
= (struct thread_info
*) all_threads
.head
;
1890 fprintf (stderr
, "Current inferior is now %ld\n",
1891 lwpid_of (get_thread_lwp (current_inferior
)));
1895 current_inferior
= NULL
;
1897 fprintf (stderr
, "Current inferior is now <NULL>\n");
1900 /* If we were waiting for this particular child to do something...
1901 well, it did something. */
1902 if (requested_child
!= NULL
)
1904 int lwpid
= lwpid_of (event_child
);
1906 /* Cancel the step-over operation --- the thread that
1907 started it is gone. */
1908 if (finish_step_over (event_child
))
1909 unstop_all_lwps (1, event_child
);
1910 delete_lwp (event_child
);
1914 delete_lwp (event_child
);
1916 /* Wait for a more interesting event. */
1920 if (event_child
->must_set_ptrace_flags
)
1922 linux_enable_event_reporting (lwpid_of (event_child
));
1923 event_child
->must_set_ptrace_flags
= 0;
1926 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1927 && *wstat
>> 16 != 0)
1929 handle_extended_wait (event_child
, *wstat
);
1933 if (WIFSTOPPED (*wstat
)
1934 && WSTOPSIG (*wstat
) == SIGSTOP
1935 && event_child
->stop_expected
)
1940 fprintf (stderr
, "Expected stop.\n");
1941 event_child
->stop_expected
= 0;
1943 should_stop
= (current_inferior
->last_resume_kind
== resume_stop
1944 || stopping_threads
!= NOT_STOPPING_THREADS
);
1948 linux_resume_one_lwp (event_child
,
1949 event_child
->stepping
, 0, NULL
);
1954 return lwpid_of (event_child
);
1961 /* Count the LWP's that have had events. */
1964 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
1966 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1967 struct thread_info
*thread
= get_lwp_thread (lp
);
1970 gdb_assert (count
!= NULL
);
1972 /* Count only resumed LWPs that have a SIGTRAP event pending that
1973 should be reported to GDB. */
1974 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1975 && thread
->last_resume_kind
!= resume_stop
1976 && lp
->status_pending_p
1977 && WIFSTOPPED (lp
->status_pending
)
1978 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1979 && !breakpoint_inserted_here (lp
->stop_pc
))
1985 /* Select the LWP (if any) that is currently being single-stepped. */
1988 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1990 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1991 struct thread_info
*thread
= get_lwp_thread (lp
);
1993 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1994 && thread
->last_resume_kind
== resume_step
1995 && lp
->status_pending_p
)
2001 /* Select the Nth LWP that has had a SIGTRAP event that should be
2005 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2007 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2008 struct thread_info
*thread
= get_lwp_thread (lp
);
2009 int *selector
= data
;
2011 gdb_assert (selector
!= NULL
);
2013 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2014 if (thread
->last_resume_kind
!= resume_stop
2015 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2016 && lp
->status_pending_p
2017 && WIFSTOPPED (lp
->status_pending
)
2018 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2019 && !breakpoint_inserted_here (lp
->stop_pc
))
2020 if ((*selector
)-- == 0)
2027 cancel_breakpoints_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 struct lwp_info
*event_lp
= data
;
2033 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
2037 /* If a LWP other than the LWP that we're reporting an event for has
2038 hit a GDB breakpoint (as opposed to some random trap signal),
2039 then just arrange for it to hit it again later. We don't keep
2040 the SIGTRAP status and don't forward the SIGTRAP signal to the
2041 LWP. We will handle the current event, eventually we will resume
2042 all LWPs, and this one will get its breakpoint trap again.
2044 If we do not do this, then we run the risk that the user will
2045 delete or disable the breakpoint, but the LWP will have already
2048 if (thread
->last_resume_kind
!= resume_stop
2049 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2050 && lp
->status_pending_p
2051 && WIFSTOPPED (lp
->status_pending
)
2052 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2054 && !lp
->stopped_by_watchpoint
2055 && cancel_breakpoint (lp
))
2056 /* Throw away the SIGTRAP. */
2057 lp
->status_pending_p
= 0;
2063 linux_cancel_breakpoints (void)
2065 find_inferior (&all_lwps
, cancel_breakpoints_callback
, NULL
);
2068 /* Select one LWP out of those that have events pending. */
2071 select_event_lwp (struct lwp_info
**orig_lp
)
2074 int random_selector
;
2075 struct lwp_info
*event_lp
;
2077 /* Give preference to any LWP that is being single-stepped. */
2079 = (struct lwp_info
*) find_inferior (&all_lwps
,
2080 select_singlestep_lwp_callback
, NULL
);
2081 if (event_lp
!= NULL
)
2085 "SEL: Select single-step %s\n",
2086 target_pid_to_str (ptid_of (event_lp
)));
2090 /* No single-stepping LWP. Select one at random, out of those
2091 which have had SIGTRAP events. */
2093 /* First see how many SIGTRAP events we have. */
2094 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
2096 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
2097 random_selector
= (int)
2098 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2100 if (debug_threads
&& num_events
> 1)
2102 "SEL: Found %d SIGTRAP events, selecting #%d\n",
2103 num_events
, random_selector
);
2105 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
2106 select_event_lwp_callback
,
2110 if (event_lp
!= NULL
)
2112 /* Switch the event LWP. */
2113 *orig_lp
= event_lp
;
2117 /* Decrement the suspend count of an LWP. */
2120 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2122 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2124 /* Ignore EXCEPT. */
2130 gdb_assert (lwp
->suspended
>= 0);
2134 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2138 unsuspend_all_lwps (struct lwp_info
*except
)
2140 find_inferior (&all_lwps
, unsuspend_one_lwp
, except
);
2143 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2144 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2146 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2147 static ptid_t
linux_wait_1 (ptid_t ptid
,
2148 struct target_waitstatus
*ourstatus
,
2149 int target_options
);
2151 /* Stabilize threads (move out of jump pads).
2153 If a thread is midway collecting a fast tracepoint, we need to
2154 finish the collection and move it out of the jump pad before
2155 reporting the signal.
2157 This avoids recursion while collecting (when a signal arrives
2158 midway, and the signal handler itself collects), which would trash
2159 the trace buffer. In case the user set a breakpoint in a signal
2160 handler, this avoids the backtrace showing the jump pad, etc..
2161 Most importantly, there are certain things we can't do safely if
2162 threads are stopped in a jump pad (or in its callee's). For
2165 - starting a new trace run. A thread still collecting the
2166 previous run, could trash the trace buffer when resumed. The trace
2167 buffer control structures would have been reset but the thread had
2168 no way to tell. The thread could even midway memcpy'ing to the
2169 buffer, which would mean that when resumed, it would clobber the
2170 trace buffer that had been set for a new run.
2172 - we can't rewrite/reuse the jump pads for new tracepoints
2173 safely. Say you do tstart while a thread is stopped midway while
2174 collecting. When the thread is later resumed, it finishes the
2175 collection, and returns to the jump pad, to execute the original
2176 instruction that was under the tracepoint jump at the time the
2177 older run had been started. If the jump pad had been rewritten
2178 since for something else in the new run, the thread would now
2179 execute the wrong / random instructions. */
2182 linux_stabilize_threads (void)
2184 struct thread_info
*save_inferior
;
2185 struct lwp_info
*lwp_stuck
;
2188 = (struct lwp_info
*) find_inferior (&all_lwps
,
2189 stuck_in_jump_pad_callback
, NULL
);
2190 if (lwp_stuck
!= NULL
)
2193 fprintf (stderr
, "can't stabilize, LWP %ld is stuck in jump pad\n",
2194 lwpid_of (lwp_stuck
));
2198 save_inferior
= current_inferior
;
2200 stabilizing_threads
= 1;
2203 for_each_inferior (&all_lwps
, move_out_of_jump_pad_callback
);
2205 /* Loop until all are stopped out of the jump pads. */
2206 while (find_inferior (&all_lwps
, lwp_running
, NULL
) != NULL
)
2208 struct target_waitstatus ourstatus
;
2209 struct lwp_info
*lwp
;
2212 /* Note that we go through the full wait even loop. While
2213 moving threads out of jump pad, we need to be able to step
2214 over internal breakpoints and such. */
2215 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2217 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2219 lwp
= get_thread_lwp (current_inferior
);
2224 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2225 || current_inferior
->last_resume_kind
== resume_stop
)
2227 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2228 enqueue_one_deferred_signal (lwp
, &wstat
);
2233 find_inferior (&all_lwps
, unsuspend_one_lwp
, NULL
);
2235 stabilizing_threads
= 0;
2237 current_inferior
= save_inferior
;
2242 = (struct lwp_info
*) find_inferior (&all_lwps
,
2243 stuck_in_jump_pad_callback
, NULL
);
2244 if (lwp_stuck
!= NULL
)
2245 fprintf (stderr
, "couldn't stabilize, LWP %ld got stuck in jump pad\n",
2246 lwpid_of (lwp_stuck
));
2250 /* Wait for process, returns status. */
2253 linux_wait_1 (ptid_t ptid
,
2254 struct target_waitstatus
*ourstatus
, int target_options
)
2257 struct lwp_info
*event_child
;
2260 int step_over_finished
;
2261 int bp_explains_trap
;
2262 int maybe_internal_trap
;
2267 /* Translate generic target options into linux options. */
2269 if (target_options
& TARGET_WNOHANG
)
2273 bp_explains_trap
= 0;
2276 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2278 /* If we were only supposed to resume one thread, only wait for
2279 that thread - if it's still alive. If it died, however - which
2280 can happen if we're coming from the thread death case below -
2281 then we need to make sure we restart the other threads. We could
2282 pick a thread at random or restart all; restarting all is less
2285 && !ptid_equal (cont_thread
, null_ptid
)
2286 && !ptid_equal (cont_thread
, minus_one_ptid
))
2288 struct thread_info
*thread
;
2290 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
2293 /* No stepping, no signal - unless one is pending already, of course. */
2296 struct thread_resume resume_info
;
2297 resume_info
.thread
= minus_one_ptid
;
2298 resume_info
.kind
= resume_continue
;
2299 resume_info
.sig
= 0;
2300 linux_resume (&resume_info
, 1);
2306 if (ptid_equal (step_over_bkpt
, null_ptid
))
2307 pid
= linux_wait_for_event (ptid
, &w
, options
);
2311 fprintf (stderr
, "step_over_bkpt set [%s], doing a blocking wait\n",
2312 target_pid_to_str (step_over_bkpt
));
2313 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2316 if (pid
== 0) /* only if TARGET_WNOHANG */
2319 event_child
= get_thread_lwp (current_inferior
);
2321 /* If we are waiting for a particular child, and it exited,
2322 linux_wait_for_event will return its exit status. Similarly if
2323 the last child exited. If this is not the last child, however,
2324 do not report it as exited until there is a 'thread exited' response
2325 available in the remote protocol. Instead, just wait for another event.
2326 This should be safe, because if the thread crashed we will already
2327 have reported the termination signal to GDB; that should stop any
2328 in-progress stepping operations, etc.
2330 Report the exit status of the last thread to exit. This matches
2331 LinuxThreads' behavior. */
2333 if (last_thread_of_process_p (current_inferior
))
2335 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2339 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2340 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2344 "\nChild exited with retcode = %x \n",
2349 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2350 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
2354 "\nChild terminated with signal = %x \n",
2359 return ptid_of (event_child
);
2364 if (!WIFSTOPPED (w
))
2368 /* If this event was not handled before, and is not a SIGTRAP, we
2369 report it. SIGILL and SIGSEGV are also treated as traps in case
2370 a breakpoint is inserted at the current PC. If this target does
2371 not support internal breakpoints at all, we also report the
2372 SIGTRAP without further processing; it's of no concern to us. */
2374 = (supports_breakpoints ()
2375 && (WSTOPSIG (w
) == SIGTRAP
2376 || ((WSTOPSIG (w
) == SIGILL
2377 || WSTOPSIG (w
) == SIGSEGV
)
2378 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2380 if (maybe_internal_trap
)
2382 /* Handle anything that requires bookkeeping before deciding to
2383 report the event or continue waiting. */
2385 /* First check if we can explain the SIGTRAP with an internal
2386 breakpoint, or if we should possibly report the event to GDB.
2387 Do this before anything that may remove or insert a
2389 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2391 /* We have a SIGTRAP, possibly a step-over dance has just
2392 finished. If so, tweak the state machine accordingly,
2393 reinsert breakpoints and delete any reinsert (software
2394 single-step) breakpoints. */
2395 step_over_finished
= finish_step_over (event_child
);
2397 /* Now invoke the callbacks of any internal breakpoints there. */
2398 check_breakpoints (event_child
->stop_pc
);
2400 /* Handle tracepoint data collecting. This may overflow the
2401 trace buffer, and cause a tracing stop, removing
2403 trace_event
= handle_tracepoints (event_child
);
2405 if (bp_explains_trap
)
2407 /* If we stepped or ran into an internal breakpoint, we've
2408 already handled it. So next time we resume (from this
2409 PC), we should step over it. */
2411 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2413 if (breakpoint_here (event_child
->stop_pc
))
2414 event_child
->need_step_over
= 1;
2419 /* We have some other signal, possibly a step-over dance was in
2420 progress, and it should be cancelled too. */
2421 step_over_finished
= finish_step_over (event_child
);
2424 /* We have all the data we need. Either report the event to GDB, or
2425 resume threads and keep waiting for more. */
2427 /* If we're collecting a fast tracepoint, finish the collection and
2428 move out of the jump pad before delivering a signal. See
2429 linux_stabilize_threads. */
2432 && WSTOPSIG (w
) != SIGTRAP
2433 && supports_fast_tracepoints ()
2434 && agent_loaded_p ())
2438 "Got signal %d for LWP %ld. Check if we need "
2439 "to defer or adjust it.\n",
2440 WSTOPSIG (w
), lwpid_of (event_child
));
2442 /* Allow debugging the jump pad itself. */
2443 if (current_inferior
->last_resume_kind
!= resume_step
2444 && maybe_move_out_of_jump_pad (event_child
, &w
))
2446 enqueue_one_deferred_signal (event_child
, &w
);
2450 "Signal %d for LWP %ld deferred (in jump pad)\n",
2451 WSTOPSIG (w
), lwpid_of (event_child
));
2453 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2458 if (event_child
->collecting_fast_tracepoint
)
2462 LWP %ld was trying to move out of the jump pad (%d). \
2463 Check if we're already there.\n",
2464 lwpid_of (event_child
),
2465 event_child
->collecting_fast_tracepoint
);
2469 event_child
->collecting_fast_tracepoint
2470 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2472 if (event_child
->collecting_fast_tracepoint
!= 1)
2474 /* No longer need this breakpoint. */
2475 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2479 "No longer need exit-jump-pad bkpt; removing it."
2480 "stopping all threads momentarily.\n");
2482 /* Other running threads could hit this breakpoint.
2483 We don't handle moribund locations like GDB does,
2484 instead we always pause all threads when removing
2485 breakpoints, so that any step-over or
2486 decr_pc_after_break adjustment is always taken
2487 care of while the breakpoint is still
2489 stop_all_lwps (1, event_child
);
2490 cancel_breakpoints ();
2492 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2493 event_child
->exit_jump_pad_bkpt
= NULL
;
2495 unstop_all_lwps (1, event_child
);
2497 gdb_assert (event_child
->suspended
>= 0);
2501 if (event_child
->collecting_fast_tracepoint
== 0)
2505 "fast tracepoint finished "
2506 "collecting successfully.\n");
2508 /* We may have a deferred signal to report. */
2509 if (dequeue_one_deferred_signal (event_child
, &w
))
2512 fprintf (stderr
, "dequeued one signal.\n");
2517 fprintf (stderr
, "no deferred signals.\n");
2519 if (stabilizing_threads
)
2521 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2522 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
2523 return ptid_of (event_child
);
2529 /* Check whether GDB would be interested in this event. */
2531 /* If GDB is not interested in this signal, don't stop other
2532 threads, and don't report it to GDB. Just resume the inferior
2533 right away. We do this for threading-related signals as well as
2534 any that GDB specifically requested we ignore. But never ignore
2535 SIGSTOP if we sent it ourselves, and do not ignore signals when
2536 stepping - they may require special handling to skip the signal
2538 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2541 && current_inferior
->last_resume_kind
!= resume_step
2543 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2544 (current_process ()->private->thread_db
!= NULL
2545 && (WSTOPSIG (w
) == __SIGRTMIN
2546 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2549 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
2550 && !(WSTOPSIG (w
) == SIGSTOP
2551 && current_inferior
->last_resume_kind
== resume_stop
))))
2553 siginfo_t info
, *info_p
;
2556 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
2557 WSTOPSIG (w
), lwpid_of (event_child
));
2559 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
),
2560 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
2564 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2565 WSTOPSIG (w
), info_p
);
2569 /* Note that all addresses are always "out of the step range" when
2570 there's no range to begin with. */
2571 in_step_range
= lwp_in_step_range (event_child
);
2573 /* If GDB wanted this thread to single step, and the thread is out
2574 of the step range, we always want to report the SIGTRAP, and let
2575 GDB handle it. Watchpoints should always be reported. So should
2576 signals we can't explain. A SIGTRAP we can't explain could be a
2577 GDB breakpoint --- we may or not support Z0 breakpoints. If we
2578 do, we're be able to handle GDB breakpoints on top of internal
2579 breakpoints, by handling the internal breakpoint and still
2580 reporting the event to GDB. If we don't, we're out of luck, GDB
2581 won't see the breakpoint hit. */
2582 report_to_gdb
= (!maybe_internal_trap
2583 || (current_inferior
->last_resume_kind
== resume_step
2585 || event_child
->stopped_by_watchpoint
2586 || (!step_over_finished
&& !in_step_range
2587 && !bp_explains_trap
&& !trace_event
)
2588 || (gdb_breakpoint_here (event_child
->stop_pc
)
2589 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
2590 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
)));
2592 run_breakpoint_commands (event_child
->stop_pc
);
2594 /* We found no reason GDB would want us to stop. We either hit one
2595 of our own breakpoints, or finished an internal step GDB
2596 shouldn't know about. */
2601 if (bp_explains_trap
)
2602 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2603 if (step_over_finished
)
2604 fprintf (stderr
, "Step-over finished.\n");
2606 fprintf (stderr
, "Tracepoint event.\n");
2607 if (lwp_in_step_range (event_child
))
2608 fprintf (stderr
, "Range stepping pc 0x%s [0x%s, 0x%s).\n",
2609 paddress (event_child
->stop_pc
),
2610 paddress (event_child
->step_range_start
),
2611 paddress (event_child
->step_range_end
));
2614 /* We're not reporting this breakpoint to GDB, so apply the
2615 decr_pc_after_break adjustment to the inferior's regcache
2618 if (the_low_target
.set_pc
!= NULL
)
2620 struct regcache
*regcache
2621 = get_thread_regcache (get_lwp_thread (event_child
), 1);
2622 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2625 /* We may have finished stepping over a breakpoint. If so,
2626 we've stopped and suspended all LWPs momentarily except the
2627 stepping one. This is where we resume them all again. We're
2628 going to keep waiting, so use proceed, which handles stepping
2629 over the next breakpoint. */
2631 fprintf (stderr
, "proceeding all threads.\n");
2633 if (step_over_finished
)
2634 unsuspend_all_lwps (event_child
);
2636 proceed_all_lwps ();
2642 if (current_inferior
->last_resume_kind
== resume_step
)
2644 if (event_child
->step_range_start
== event_child
->step_range_end
)
2645 fprintf (stderr
, "GDB wanted to single-step, reporting event.\n");
2646 else if (!lwp_in_step_range (event_child
))
2647 fprintf (stderr
, "Out of step range, 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
= GDB_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
= gdb_signal_from_host (WSTOPSIG (w
));
2726 ourstatus
->value
.sig
= gdb_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 /* Should not be called recursively. */
3076 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3078 stopping_threads
= (suspend
3079 ? STOPPING_AND_SUSPENDING_THREADS
3080 : STOPPING_THREADS
);
3083 find_inferior (&all_lwps
, suspend_and_send_sigstop_callback
, except
);
3085 find_inferior (&all_lwps
, send_sigstop_callback
, except
);
3086 for_each_inferior (&all_lwps
, wait_for_sigstop
);
3087 stopping_threads
= NOT_STOPPING_THREADS
;
3090 /* Resume execution of the inferior process.
3091 If STEP is nonzero, single-step it.
3092 If SIGNAL is nonzero, give it that signal. */
3095 linux_resume_one_lwp (struct lwp_info
*lwp
,
3096 int step
, int signal
, siginfo_t
*info
)
3098 struct thread_info
*saved_inferior
;
3099 int fast_tp_collecting
;
3101 if (lwp
->stopped
== 0)
3104 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3106 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3108 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3109 user used the "jump" command, or "set $pc = foo"). */
3110 if (lwp
->stop_pc
!= get_pc (lwp
))
3112 /* Collecting 'while-stepping' actions doesn't make sense
3114 release_while_stepping_state_list (get_lwp_thread (lwp
));
3117 /* If we have pending signals or status, and a new signal, enqueue the
3118 signal. Also enqueue the signal if we are waiting to reinsert a
3119 breakpoint; it will be picked up again below. */
3121 && (lwp
->status_pending_p
3122 || lwp
->pending_signals
!= NULL
3123 || lwp
->bp_reinsert
!= 0
3124 || fast_tp_collecting
))
3126 struct pending_signals
*p_sig
;
3127 p_sig
= xmalloc (sizeof (*p_sig
));
3128 p_sig
->prev
= lwp
->pending_signals
;
3129 p_sig
->signal
= signal
;
3131 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3133 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3134 lwp
->pending_signals
= p_sig
;
3137 if (lwp
->status_pending_p
)
3140 fprintf (stderr
, "Not resuming lwp %ld (%s, signal %d, stop %s);"
3141 " has pending status\n",
3142 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3143 lwp
->stop_expected
? "expected" : "not expected");
3147 saved_inferior
= current_inferior
;
3148 current_inferior
= get_lwp_thread (lwp
);
3151 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
3152 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3153 lwp
->stop_expected
? "expected" : "not expected");
3155 /* This bit needs some thinking about. If we get a signal that
3156 we must report while a single-step reinsert is still pending,
3157 we often end up resuming the thread. It might be better to
3158 (ew) allow a stack of pending events; then we could be sure that
3159 the reinsert happened right away and not lose any signals.
3161 Making this stack would also shrink the window in which breakpoints are
3162 uninserted (see comment in linux_wait_for_lwp) but not enough for
3163 complete correctness, so it won't solve that problem. It may be
3164 worthwhile just to solve this one, however. */
3165 if (lwp
->bp_reinsert
!= 0)
3168 fprintf (stderr
, " pending reinsert at 0x%s\n",
3169 paddress (lwp
->bp_reinsert
));
3171 if (can_hardware_single_step ())
3173 if (fast_tp_collecting
== 0)
3176 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
3178 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
3185 /* Postpone any pending signal. It was enqueued above. */
3189 if (fast_tp_collecting
== 1)
3193 lwp %ld wants to get out of fast tracepoint jump pad (exit-jump-pad-bkpt)\n",
3196 /* Postpone any pending signal. It was enqueued above. */
3199 else if (fast_tp_collecting
== 2)
3203 lwp %ld wants to get out of fast tracepoint jump pad single-stepping\n",
3206 if (can_hardware_single_step ())
3209 fatal ("moving out of jump pad single-stepping"
3210 " not implemented on this target");
3212 /* Postpone any pending signal. It was enqueued above. */
3216 /* If we have while-stepping actions in this thread set it stepping.
3217 If we have a signal to deliver, it may or may not be set to
3218 SIG_IGN, we don't know. Assume so, and allow collecting
3219 while-stepping into a signal handler. A possible smart thing to
3220 do would be to set an internal breakpoint at the signal return
3221 address, continue, and carry on catching this while-stepping
3222 action only when that breakpoint is hit. A future
3224 if (get_lwp_thread (lwp
)->while_stepping
!= NULL
3225 && can_hardware_single_step ())
3229 "lwp %ld has a while-stepping action -> forcing step.\n",
3234 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
3236 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
3237 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
3238 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
3241 /* If we have pending signals, consume one unless we are trying to
3242 reinsert a breakpoint or we're trying to finish a fast tracepoint
3244 if (lwp
->pending_signals
!= NULL
3245 && lwp
->bp_reinsert
== 0
3246 && fast_tp_collecting
== 0)
3248 struct pending_signals
**p_sig
;
3250 p_sig
= &lwp
->pending_signals
;
3251 while ((*p_sig
)->prev
!= NULL
)
3252 p_sig
= &(*p_sig
)->prev
;
3254 signal
= (*p_sig
)->signal
;
3255 if ((*p_sig
)->info
.si_signo
!= 0)
3256 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
3263 if (the_low_target
.prepare_to_resume
!= NULL
)
3264 the_low_target
.prepare_to_resume (lwp
);
3266 regcache_invalidate_thread (get_lwp_thread (lwp
));
3269 lwp
->stopped_by_watchpoint
= 0;
3270 lwp
->stepping
= step
;
3271 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
),
3272 (PTRACE_TYPE_ARG3
) 0,
3273 /* Coerce to a uintptr_t first to avoid potential gcc warning
3274 of coercing an 8 byte integer to a 4 byte pointer. */
3275 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
3277 current_inferior
= saved_inferior
;
3280 /* ESRCH from ptrace either means that the thread was already
3281 running (an error) or that it is gone (a race condition). If
3282 it's gone, we will get a notification the next time we wait,
3283 so we can ignore the error. We could differentiate these
3284 two, but it's tricky without waiting; the thread still exists
3285 as a zombie, so sending it signal 0 would succeed. So just
3290 perror_with_name ("ptrace");
3294 struct thread_resume_array
3296 struct thread_resume
*resume
;
3300 /* This function is called once per thread. We look up the thread
3301 in RESUME_PTR, and mark the thread with a pointer to the appropriate
3304 This algorithm is O(threads * resume elements), but resume elements
3305 is small (and will remain small at least until GDB supports thread
3308 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3310 struct lwp_info
*lwp
;
3311 struct thread_info
*thread
;
3313 struct thread_resume_array
*r
;
3315 thread
= (struct thread_info
*) entry
;
3316 lwp
= get_thread_lwp (thread
);
3319 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3321 ptid_t ptid
= r
->resume
[ndx
].thread
;
3322 if (ptid_equal (ptid
, minus_one_ptid
)
3323 || ptid_equal (ptid
, entry
->id
)
3324 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
3326 || (ptid_get_pid (ptid
) == pid_of (lwp
)
3327 && (ptid_is_pid (ptid
)
3328 || ptid_get_lwp (ptid
) == -1)))
3330 if (r
->resume
[ndx
].kind
== resume_stop
3331 && thread
->last_resume_kind
== resume_stop
)
3334 fprintf (stderr
, "already %s LWP %ld at GDB's request\n",
3335 thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
3343 lwp
->resume
= &r
->resume
[ndx
];
3344 thread
->last_resume_kind
= lwp
->resume
->kind
;
3346 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
3347 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
3349 /* If we had a deferred signal to report, dequeue one now.
3350 This can happen if LWP gets more than one signal while
3351 trying to get out of a jump pad. */
3353 && !lwp
->status_pending_p
3354 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3356 lwp
->status_pending_p
= 1;
3360 "Dequeueing deferred signal %d for LWP %ld, "
3361 "leaving status pending.\n",
3362 WSTOPSIG (lwp
->status_pending
), lwpid_of (lwp
));
3369 /* No resume action for this thread. */
3376 /* Set *FLAG_P if this lwp has an interesting status pending. */
3378 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3380 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3382 /* LWPs which will not be resumed are not interesting, because
3383 we might not wait for them next time through linux_wait. */
3384 if (lwp
->resume
== NULL
)
3387 if (lwp
->status_pending_p
)
3388 * (int *) flag_p
= 1;
3393 /* Return 1 if this lwp that GDB wants running is stopped at an
3394 internal breakpoint that we need to step over. It assumes that any
3395 required STOP_PC adjustment has already been propagated to the
3396 inferior's regcache. */
3399 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3401 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3402 struct thread_info
*thread
;
3403 struct thread_info
*saved_inferior
;
3406 /* LWPs which will not be resumed are not interesting, because we
3407 might not wait for them next time through linux_wait. */
3413 "Need step over [LWP %ld]? Ignoring, not stopped\n",
3418 thread
= get_lwp_thread (lwp
);
3420 if (thread
->last_resume_kind
== resume_stop
)
3424 "Need step over [LWP %ld]? Ignoring, should remain stopped\n",
3429 gdb_assert (lwp
->suspended
>= 0);
3435 "Need step over [LWP %ld]? Ignoring, suspended\n",
3440 if (!lwp
->need_step_over
)
3444 "Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
3447 if (lwp
->status_pending_p
)
3451 "Need step over [LWP %ld]? Ignoring, has pending status.\n",
3456 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3460 /* If the PC has changed since we stopped, then don't do anything,
3461 and let the breakpoint/tracepoint be hit. This happens if, for
3462 instance, GDB handled the decr_pc_after_break subtraction itself,
3463 GDB is OOL stepping this thread, or the user has issued a "jump"
3464 command, or poked thread's registers herself. */
3465 if (pc
!= lwp
->stop_pc
)
3469 "Need step over [LWP %ld]? Cancelling, PC was changed. "
3470 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3471 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
3473 lwp
->need_step_over
= 0;
3477 saved_inferior
= current_inferior
;
3478 current_inferior
= thread
;
3480 /* We can only step over breakpoints we know about. */
3481 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3483 /* Don't step over a breakpoint that GDB expects to hit
3484 though. If the condition is being evaluated on the target's side
3485 and it evaluate to false, step over this breakpoint as well. */
3486 if (gdb_breakpoint_here (pc
)
3487 && gdb_condition_true_at_breakpoint (pc
)
3488 && gdb_no_commands_at_breakpoint (pc
))
3492 "Need step over [LWP %ld]? yes, but found"
3493 " GDB breakpoint at 0x%s; skipping step over\n",
3494 lwpid_of (lwp
), paddress (pc
));
3496 current_inferior
= saved_inferior
;
3503 "Need step over [LWP %ld]? yes, "
3504 "found breakpoint at 0x%s\n",
3505 lwpid_of (lwp
), paddress (pc
));
3507 /* We've found an lwp that needs stepping over --- return 1 so
3508 that find_inferior stops looking. */
3509 current_inferior
= saved_inferior
;
3511 /* If the step over is cancelled, this is set again. */
3512 lwp
->need_step_over
= 0;
3517 current_inferior
= saved_inferior
;
3521 "Need step over [LWP %ld]? No, no breakpoint found at 0x%s\n",
3522 lwpid_of (lwp
), paddress (pc
));
3527 /* Start a step-over operation on LWP. When LWP stopped at a
3528 breakpoint, to make progress, we need to remove the breakpoint out
3529 of the way. If we let other threads run while we do that, they may
3530 pass by the breakpoint location and miss hitting it. To avoid
3531 that, a step-over momentarily stops all threads while LWP is
3532 single-stepped while the breakpoint is temporarily uninserted from
3533 the inferior. When the single-step finishes, we reinsert the
3534 breakpoint, and let all threads that are supposed to be running,
3537 On targets that don't support hardware single-step, we don't
3538 currently support full software single-stepping. Instead, we only
3539 support stepping over the thread event breakpoint, by asking the
3540 low target where to place a reinsert breakpoint. Since this
3541 routine assumes the breakpoint being stepped over is a thread event
3542 breakpoint, it usually assumes the return address of the current
3543 function is a good enough place to set the reinsert breakpoint. */
3546 start_step_over (struct lwp_info
*lwp
)
3548 struct thread_info
*saved_inferior
;
3554 "Starting step-over on LWP %ld. Stopping all threads\n",
3557 stop_all_lwps (1, lwp
);
3558 gdb_assert (lwp
->suspended
== 0);
3561 fprintf (stderr
, "Done stopping all threads for step-over.\n");
3563 /* Note, we should always reach here with an already adjusted PC,
3564 either by GDB (if we're resuming due to GDB's request), or by our
3565 caller, if we just finished handling an internal breakpoint GDB
3566 shouldn't care about. */
3569 saved_inferior
= current_inferior
;
3570 current_inferior
= get_lwp_thread (lwp
);
3572 lwp
->bp_reinsert
= pc
;
3573 uninsert_breakpoints_at (pc
);
3574 uninsert_fast_tracepoint_jumps_at (pc
);
3576 if (can_hardware_single_step ())
3582 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3583 set_reinsert_breakpoint (raddr
);
3587 current_inferior
= saved_inferior
;
3589 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3591 /* Require next event from this LWP. */
3592 step_over_bkpt
= lwp
->head
.id
;
3596 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3597 start_step_over, if still there, and delete any reinsert
3598 breakpoints we've set, on non hardware single-step targets. */
3601 finish_step_over (struct lwp_info
*lwp
)
3603 if (lwp
->bp_reinsert
!= 0)
3606 fprintf (stderr
, "Finished step over.\n");
3608 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3609 may be no breakpoint to reinsert there by now. */
3610 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3611 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3613 lwp
->bp_reinsert
= 0;
3615 /* Delete any software-single-step reinsert breakpoints. No
3616 longer needed. We don't have to worry about other threads
3617 hitting this trap, and later not being able to explain it,
3618 because we were stepping over a breakpoint, and we hold all
3619 threads but LWP stopped while doing that. */
3620 if (!can_hardware_single_step ())
3621 delete_reinsert_breakpoints ();
3623 step_over_bkpt
= null_ptid
;
3630 /* This function is called once per thread. We check the thread's resume
3631 request, which will tell us whether to resume, step, or leave the thread
3632 stopped; and what signal, if any, it should be sent.
3634 For threads which we aren't explicitly told otherwise, we preserve
3635 the stepping flag; this is used for stepping over gdbserver-placed
3638 If pending_flags was set in any thread, we queue any needed
3639 signals, since we won't actually resume. We already have a pending
3640 event to report, so we don't need to preserve any step requests;
3641 they should be re-issued if necessary. */
3644 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3646 struct lwp_info
*lwp
;
3647 struct thread_info
*thread
;
3649 int leave_all_stopped
= * (int *) arg
;
3652 thread
= (struct thread_info
*) entry
;
3653 lwp
= get_thread_lwp (thread
);
3655 if (lwp
->resume
== NULL
)
3658 if (lwp
->resume
->kind
== resume_stop
)
3661 fprintf (stderr
, "resume_stop request for LWP %ld\n", lwpid_of (lwp
));
3666 fprintf (stderr
, "stopping LWP %ld\n", lwpid_of (lwp
));
3668 /* Stop the thread, and wait for the event asynchronously,
3669 through the event loop. */
3675 fprintf (stderr
, "already stopped LWP %ld\n",
3678 /* The LWP may have been stopped in an internal event that
3679 was not meant to be notified back to GDB (e.g., gdbserver
3680 breakpoint), so we should be reporting a stop event in
3683 /* If the thread already has a pending SIGSTOP, this is a
3684 no-op. Otherwise, something later will presumably resume
3685 the thread and this will cause it to cancel any pending
3686 operation, due to last_resume_kind == resume_stop. If
3687 the thread already has a pending status to report, we
3688 will still report it the next time we wait - see
3689 status_pending_p_callback. */
3691 /* If we already have a pending signal to report, then
3692 there's no need to queue a SIGSTOP, as this means we're
3693 midway through moving the LWP out of the jumppad, and we
3694 will report the pending signal as soon as that is
3696 if (lwp
->pending_signals_to_report
== NULL
)
3700 /* For stop requests, we're done. */
3702 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3706 /* If this thread which is about to be resumed has a pending status,
3707 then don't resume any threads - we can just report the pending
3708 status. Make sure to queue any signals that would otherwise be
3709 sent. In all-stop mode, we do this decision based on if *any*
3710 thread has a pending status. If there's a thread that needs the
3711 step-over-breakpoint dance, then don't resume any other thread
3712 but that particular one. */
3713 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
3718 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
3720 step
= (lwp
->resume
->kind
== resume_step
);
3721 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
3726 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
3728 /* If we have a new signal, enqueue the signal. */
3729 if (lwp
->resume
->sig
!= 0)
3731 struct pending_signals
*p_sig
;
3732 p_sig
= xmalloc (sizeof (*p_sig
));
3733 p_sig
->prev
= lwp
->pending_signals
;
3734 p_sig
->signal
= lwp
->resume
->sig
;
3735 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3737 /* If this is the same signal we were previously stopped by,
3738 make sure to queue its siginfo. We can ignore the return
3739 value of ptrace; if it fails, we'll skip
3740 PTRACE_SETSIGINFO. */
3741 if (WIFSTOPPED (lwp
->last_status
)
3742 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
3743 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
3746 lwp
->pending_signals
= p_sig
;
3750 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3756 linux_resume (struct thread_resume
*resume_info
, size_t n
)
3758 struct thread_resume_array array
= { resume_info
, n
};
3759 struct lwp_info
*need_step_over
= NULL
;
3761 int leave_all_stopped
;
3763 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
3765 /* If there is a thread which would otherwise be resumed, which has
3766 a pending status, then don't resume any threads - we can just
3767 report the pending status. Make sure to queue any signals that
3768 would otherwise be sent. In non-stop mode, we'll apply this
3769 logic to each thread individually. We consume all pending events
3770 before considering to start a step-over (in all-stop). */
3773 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
3775 /* If there is a thread which would otherwise be resumed, which is
3776 stopped at a breakpoint that needs stepping over, then don't
3777 resume any threads - have it step over the breakpoint with all
3778 other threads stopped, then resume all threads again. Make sure
3779 to queue any signals that would otherwise be delivered or
3781 if (!any_pending
&& supports_breakpoints ())
3783 = (struct lwp_info
*) find_inferior (&all_lwps
,
3784 need_step_over_p
, NULL
);
3786 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
3790 if (need_step_over
!= NULL
)
3791 fprintf (stderr
, "Not resuming all, need step over\n");
3792 else if (any_pending
)
3794 "Not resuming, all-stop and found "
3795 "an LWP with pending status\n");
3797 fprintf (stderr
, "Resuming, no pending status or step over needed\n");
3800 /* Even if we're leaving threads stopped, queue all signals we'd
3801 otherwise deliver. */
3802 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
3805 start_step_over (need_step_over
);
3808 /* This function is called once per thread. We check the thread's
3809 last resume request, which will tell us whether to resume, step, or
3810 leave the thread stopped. Any signal the client requested to be
3811 delivered has already been enqueued at this point.
3813 If any thread that GDB wants running is stopped at an internal
3814 breakpoint that needs stepping over, we start a step-over operation
3815 on that particular thread, and leave all others stopped. */
3818 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3820 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3821 struct thread_info
*thread
;
3829 "proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
3834 fprintf (stderr
, " LWP %ld already running\n", lwpid_of (lwp
));
3838 thread
= get_lwp_thread (lwp
);
3840 if (thread
->last_resume_kind
== resume_stop
3841 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
3844 fprintf (stderr
, " client wants LWP to remain %ld stopped\n",
3849 if (lwp
->status_pending_p
)
3852 fprintf (stderr
, " LWP %ld has pending status, leaving stopped\n",
3857 gdb_assert (lwp
->suspended
>= 0);
3862 fprintf (stderr
, " LWP %ld is suspended\n", lwpid_of (lwp
));
3866 if (thread
->last_resume_kind
== resume_stop
3867 && lwp
->pending_signals_to_report
== NULL
3868 && lwp
->collecting_fast_tracepoint
== 0)
3870 /* We haven't reported this LWP as stopped yet (otherwise, the
3871 last_status.kind check above would catch it, and we wouldn't
3872 reach here. This LWP may have been momentarily paused by a
3873 stop_all_lwps call while handling for example, another LWP's
3874 step-over. In that case, the pending expected SIGSTOP signal
3875 that was queued at vCont;t handling time will have already
3876 been consumed by wait_for_sigstop, and so we need to requeue
3877 another one here. Note that if the LWP already has a SIGSTOP
3878 pending, this is a no-op. */
3882 "Client wants LWP %ld to stop. "
3883 "Making sure it has a SIGSTOP pending\n",
3889 step
= thread
->last_resume_kind
== resume_step
;
3890 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3895 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3897 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3903 gdb_assert (lwp
->suspended
>= 0);
3905 return proceed_one_lwp (entry
, except
);
3908 /* When we finish a step-over, set threads running again. If there's
3909 another thread that may need a step-over, now's the time to start
3910 it. Eventually, we'll move all threads past their breakpoints. */
3913 proceed_all_lwps (void)
3915 struct lwp_info
*need_step_over
;
3917 /* If there is a thread which would otherwise be resumed, which is
3918 stopped at a breakpoint that needs stepping over, then don't
3919 resume any threads - have it step over the breakpoint with all
3920 other threads stopped, then resume all threads again. */
3922 if (supports_breakpoints ())
3925 = (struct lwp_info
*) find_inferior (&all_lwps
,
3926 need_step_over_p
, NULL
);
3928 if (need_step_over
!= NULL
)
3931 fprintf (stderr
, "proceed_all_lwps: found "
3932 "thread %ld needing a step-over\n",
3933 lwpid_of (need_step_over
));
3935 start_step_over (need_step_over
);
3941 fprintf (stderr
, "Proceeding, no step-over needed\n");
3943 find_inferior (&all_lwps
, proceed_one_lwp
, NULL
);
3946 /* Stopped LWPs that the client wanted to be running, that don't have
3947 pending statuses, are set to run again, except for EXCEPT, if not
3948 NULL. This undoes a stop_all_lwps call. */
3951 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
3957 "unstopping all lwps, except=(LWP %ld)\n", lwpid_of (except
));
3960 "unstopping all lwps\n");
3964 find_inferior (&all_lwps
, unsuspend_and_proceed_one_lwp
, except
);
3966 find_inferior (&all_lwps
, proceed_one_lwp
, except
);
3970 #ifdef HAVE_LINUX_REGSETS
3972 #define use_linux_regsets 1
3974 /* Returns true if REGSET has been disabled. */
3977 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
3979 return (info
->disabled_regsets
!= NULL
3980 && info
->disabled_regsets
[regset
- info
->regsets
]);
3983 /* Disable REGSET. */
3986 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
3990 dr_offset
= regset
- info
->regsets
;
3991 if (info
->disabled_regsets
== NULL
)
3992 info
->disabled_regsets
= xcalloc (1, info
->num_regsets
);
3993 info
->disabled_regsets
[dr_offset
] = 1;
3997 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
3998 struct regcache
*regcache
)
4000 struct regset_info
*regset
;
4001 int saw_general_regs
= 0;
4005 regset
= regsets_info
->regsets
;
4007 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4008 while (regset
->size
>= 0)
4013 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
4019 buf
= xmalloc (regset
->size
);
4021 nt_type
= regset
->nt_type
;
4025 iov
.iov_len
= regset
->size
;
4026 data
= (void *) &iov
;
4032 res
= ptrace (regset
->get_request
, pid
,
4033 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4035 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4041 /* If we get EIO on a regset, do not try it again for
4042 this process mode. */
4043 disable_regset (regsets_info
, regset
);
4050 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4055 else if (regset
->type
== GENERAL_REGS
)
4056 saw_general_regs
= 1;
4057 regset
->store_function (regcache
, buf
);
4061 if (saw_general_regs
)
4068 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
4069 struct regcache
*regcache
)
4071 struct regset_info
*regset
;
4072 int saw_general_regs
= 0;
4076 regset
= regsets_info
->regsets
;
4078 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4079 while (regset
->size
>= 0)
4084 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
4090 buf
= xmalloc (regset
->size
);
4092 /* First fill the buffer with the current register set contents,
4093 in case there are any items in the kernel's regset that are
4094 not in gdbserver's regcache. */
4096 nt_type
= regset
->nt_type
;
4100 iov
.iov_len
= regset
->size
;
4101 data
= (void *) &iov
;
4107 res
= ptrace (regset
->get_request
, pid
,
4108 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4110 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4115 /* Then overlay our cached registers on that. */
4116 regset
->fill_function (regcache
, buf
);
4118 /* Only now do we write the register set. */
4120 res
= ptrace (regset
->set_request
, pid
,
4121 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4123 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4131 /* If we get EIO on a regset, do not try it again for
4132 this process mode. */
4133 disable_regset (regsets_info
, regset
);
4137 else if (errno
== ESRCH
)
4139 /* At this point, ESRCH should mean the process is
4140 already gone, in which case we simply ignore attempts
4141 to change its registers. See also the related
4142 comment in linux_resume_one_lwp. */
4148 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4151 else if (regset
->type
== GENERAL_REGS
)
4152 saw_general_regs
= 1;
4156 if (saw_general_regs
)
4162 #else /* !HAVE_LINUX_REGSETS */
4164 #define use_linux_regsets 0
4165 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
4166 #define regsets_store_inferior_registers(regsets_info, regcache) 1
4170 /* Return 1 if register REGNO is supported by one of the regset ptrace
4171 calls or 0 if it has to be transferred individually. */
4174 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
4176 unsigned char mask
= 1 << (regno
% 8);
4177 size_t index
= regno
/ 8;
4179 return (use_linux_regsets
4180 && (regs_info
->regset_bitmap
== NULL
4181 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
4184 #ifdef HAVE_LINUX_USRREGS
4187 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
4191 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
4192 error ("Invalid register number %d.", regnum
);
4194 addr
= usrregs
->regmap
[regnum
];
4199 /* Fetch one register. */
4201 fetch_register (const struct usrregs_info
*usrregs
,
4202 struct regcache
*regcache
, int regno
)
4209 if (regno
>= usrregs
->num_regs
)
4211 if ((*the_low_target
.cannot_fetch_register
) (regno
))
4214 regaddr
= register_addr (usrregs
, regno
);
4218 size
= ((register_size (regcache
->tdesc
, regno
)
4219 + sizeof (PTRACE_XFER_TYPE
) - 1)
4220 & -sizeof (PTRACE_XFER_TYPE
));
4221 buf
= alloca (size
);
4223 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4224 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4227 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
4228 ptrace (PTRACE_PEEKUSER
, pid
,
4229 /* Coerce to a uintptr_t first to avoid potential gcc warning
4230 of coercing an 8 byte integer to a 4 byte pointer. */
4231 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
4232 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4234 error ("reading register %d: %s", regno
, strerror (errno
));
4237 if (the_low_target
.supply_ptrace_register
)
4238 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
4240 supply_register (regcache
, regno
, buf
);
4243 /* Store one register. */
4245 store_register (const struct usrregs_info
*usrregs
,
4246 struct regcache
*regcache
, int regno
)
4253 if (regno
>= usrregs
->num_regs
)
4255 if ((*the_low_target
.cannot_store_register
) (regno
))
4258 regaddr
= register_addr (usrregs
, regno
);
4262 size
= ((register_size (regcache
->tdesc
, regno
)
4263 + sizeof (PTRACE_XFER_TYPE
) - 1)
4264 & -sizeof (PTRACE_XFER_TYPE
));
4265 buf
= alloca (size
);
4266 memset (buf
, 0, size
);
4268 if (the_low_target
.collect_ptrace_register
)
4269 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
4271 collect_register (regcache
, regno
, buf
);
4273 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4274 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4277 ptrace (PTRACE_POKEUSER
, pid
,
4278 /* Coerce to a uintptr_t first to avoid potential gcc warning
4279 about coercing an 8 byte integer to a 4 byte pointer. */
4280 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
4281 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
4284 /* At this point, ESRCH should mean the process is
4285 already gone, in which case we simply ignore attempts
4286 to change its registers. See also the related
4287 comment in linux_resume_one_lwp. */
4291 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
4292 error ("writing register %d: %s", regno
, strerror (errno
));
4294 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4298 /* Fetch all registers, or just one, from the child process.
4299 If REGNO is -1, do this for all registers, skipping any that are
4300 assumed to have been retrieved by regsets_fetch_inferior_registers,
4301 unless ALL is non-zero.
4302 Otherwise, REGNO specifies which register (so we can save time). */
4304 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
4305 struct regcache
*regcache
, int regno
, int all
)
4307 struct usrregs_info
*usr
= regs_info
->usrregs
;
4311 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4312 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4313 fetch_register (usr
, regcache
, regno
);
4316 fetch_register (usr
, regcache
, regno
);
4319 /* Store our register values back into the inferior.
4320 If REGNO is -1, do this for all registers, skipping any that are
4321 assumed to have been saved by regsets_store_inferior_registers,
4322 unless ALL is non-zero.
4323 Otherwise, REGNO specifies which register (so we can save time). */
4325 usr_store_inferior_registers (const struct regs_info
*regs_info
,
4326 struct regcache
*regcache
, int regno
, int all
)
4328 struct usrregs_info
*usr
= regs_info
->usrregs
;
4332 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4333 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4334 store_register (usr
, regcache
, regno
);
4337 store_register (usr
, regcache
, regno
);
4340 #else /* !HAVE_LINUX_USRREGS */
4342 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4343 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4349 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4353 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
4357 if (the_low_target
.fetch_register
!= NULL
4358 && regs_info
->usrregs
!= NULL
)
4359 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
4360 (*the_low_target
.fetch_register
) (regcache
, regno
);
4362 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
4363 if (regs_info
->usrregs
!= NULL
)
4364 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
4368 if (the_low_target
.fetch_register
!= NULL
4369 && (*the_low_target
.fetch_register
) (regcache
, regno
))
4372 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
4374 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
4376 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
4377 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
4382 linux_store_registers (struct regcache
*regcache
, int regno
)
4386 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
4390 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
4392 if (regs_info
->usrregs
!= NULL
)
4393 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
4397 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
4399 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
4401 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
4402 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
4407 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4408 to debugger memory starting at MYADDR. */
4411 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4413 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4414 register PTRACE_XFER_TYPE
*buffer
;
4415 register CORE_ADDR addr
;
4422 /* Try using /proc. Don't bother for one word. */
4423 if (len
>= 3 * sizeof (long))
4427 /* We could keep this file open and cache it - possibly one per
4428 thread. That requires some juggling, but is even faster. */
4429 sprintf (filename
, "/proc/%d/mem", pid
);
4430 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4434 /* If pread64 is available, use it. It's faster if the kernel
4435 supports it (only one syscall), and it's 64-bit safe even on
4436 32-bit platforms (for instance, SPARC debugging a SPARC64
4439 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
4442 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
4443 bytes
= read (fd
, myaddr
, len
);
4450 /* Some data was read, we'll try to get the rest with ptrace. */
4460 /* Round starting address down to longword boundary. */
4461 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4462 /* Round ending address up; get number of longwords that makes. */
4463 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4464 / sizeof (PTRACE_XFER_TYPE
));
4465 /* Allocate buffer of that many longwords. */
4466 buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4468 /* Read all the longwords */
4470 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4472 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4473 about coercing an 8 byte integer to a 4 byte pointer. */
4474 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4475 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4476 (PTRACE_TYPE_ARG4
) 0);
4482 /* Copy appropriate bytes out of the buffer. */
4485 i
*= sizeof (PTRACE_XFER_TYPE
);
4486 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
4488 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4495 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4496 memory at MEMADDR. On failure (cannot write to the inferior)
4497 returns the value of errno. Always succeeds if LEN is zero. */
4500 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4503 /* Round starting address down to longword boundary. */
4504 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4505 /* Round ending address up; get number of longwords that makes. */
4507 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4508 / sizeof (PTRACE_XFER_TYPE
);
4510 /* Allocate buffer of that many longwords. */
4511 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4512 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4514 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4518 /* Zero length write always succeeds. */
4524 /* Dump up to four bytes. */
4525 unsigned int val
= * (unsigned int *) myaddr
;
4531 val
= val
& 0xffffff;
4532 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4533 val
, (long)memaddr
);
4536 /* Fill start and end extra bytes of buffer with existing memory data. */
4539 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4540 about coercing an 8 byte integer to a 4 byte pointer. */
4541 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4542 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4543 (PTRACE_TYPE_ARG4
) 0);
4551 = ptrace (PTRACE_PEEKTEXT
, pid
,
4552 /* Coerce to a uintptr_t first to avoid potential gcc warning
4553 about coercing an 8 byte integer to a 4 byte pointer. */
4554 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
4555 * sizeof (PTRACE_XFER_TYPE
)),
4556 (PTRACE_TYPE_ARG4
) 0);
4561 /* Copy data to be written over corresponding part of buffer. */
4563 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4566 /* Write the entire buffer. */
4568 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4571 ptrace (PTRACE_POKETEXT
, pid
,
4572 /* Coerce to a uintptr_t first to avoid potential gcc warning
4573 about coercing an 8 byte integer to a 4 byte pointer. */
4574 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4575 (PTRACE_TYPE_ARG4
) buffer
[i
]);
4584 linux_look_up_symbols (void)
4586 #ifdef USE_THREAD_DB
4587 struct process_info
*proc
= current_process ();
4589 if (proc
->private->thread_db
!= NULL
)
4592 /* If the kernel supports tracing clones, then we don't need to
4593 use the magic thread event breakpoint to learn about
4595 thread_db_init (!linux_supports_traceclone ());
4600 linux_request_interrupt (void)
4602 extern unsigned long signal_pid
;
4604 if (!ptid_equal (cont_thread
, null_ptid
)
4605 && !ptid_equal (cont_thread
, minus_one_ptid
))
4607 struct lwp_info
*lwp
;
4610 lwp
= get_thread_lwp (current_inferior
);
4611 lwpid
= lwpid_of (lwp
);
4612 kill_lwp (lwpid
, SIGINT
);
4615 kill_lwp (signal_pid
, SIGINT
);
4618 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4619 to debugger memory starting at MYADDR. */
4622 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4624 char filename
[PATH_MAX
];
4626 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4628 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4630 fd
= open (filename
, O_RDONLY
);
4634 if (offset
!= (CORE_ADDR
) 0
4635 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4638 n
= read (fd
, myaddr
, len
);
4645 /* These breakpoint and watchpoint related wrapper functions simply
4646 pass on the function call if the target has registered a
4647 corresponding function. */
4650 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
4652 if (the_low_target
.insert_point
!= NULL
)
4653 return the_low_target
.insert_point (type
, addr
, len
);
4655 /* Unsupported (see target.h). */
4660 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
4662 if (the_low_target
.remove_point
!= NULL
)
4663 return the_low_target
.remove_point (type
, addr
, len
);
4665 /* Unsupported (see target.h). */
4670 linux_stopped_by_watchpoint (void)
4672 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4674 return lwp
->stopped_by_watchpoint
;
4678 linux_stopped_data_address (void)
4680 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4682 return lwp
->stopped_data_address
;
4685 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
4686 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
4687 && defined(PT_TEXT_END_ADDR)
4689 /* This is only used for targets that define PT_TEXT_ADDR,
4690 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
4691 the target has different ways of acquiring this information, like
4694 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4695 to tell gdb about. */
4698 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
4700 unsigned long text
, text_end
, data
;
4701 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4705 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
4706 (PTRACE_TYPE_ARG4
) 0);
4707 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
4708 (PTRACE_TYPE_ARG4
) 0);
4709 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
4710 (PTRACE_TYPE_ARG4
) 0);
4714 /* Both text and data offsets produced at compile-time (and so
4715 used by gdb) are relative to the beginning of the program,
4716 with the data segment immediately following the text segment.
4717 However, the actual runtime layout in memory may put the data
4718 somewhere else, so when we send gdb a data base-address, we
4719 use the real data base address and subtract the compile-time
4720 data base-address from it (which is just the length of the
4721 text segment). BSS immediately follows data in both
4724 *data_p
= data
- (text_end
- text
);
4733 linux_qxfer_osdata (const char *annex
,
4734 unsigned char *readbuf
, unsigned const char *writebuf
,
4735 CORE_ADDR offset
, int len
)
4737 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
4740 /* Convert a native/host siginfo object, into/from the siginfo in the
4741 layout of the inferiors' architecture. */
4744 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
4748 if (the_low_target
.siginfo_fixup
!= NULL
)
4749 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4751 /* If there was no callback, or the callback didn't do anything,
4752 then just do a straight memcpy. */
4756 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
4758 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
4763 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
4764 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
4768 char inf_siginfo
[sizeof (siginfo_t
)];
4770 if (current_inferior
== NULL
)
4773 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4776 fprintf (stderr
, "%s siginfo for lwp %d.\n",
4777 readbuf
!= NULL
? "Reading" : "Writing",
4780 if (offset
>= sizeof (siginfo
))
4783 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
4786 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4787 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4788 inferior with a 64-bit GDBSERVER should look the same as debugging it
4789 with a 32-bit GDBSERVER, we need to convert it. */
4790 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4792 if (offset
+ len
> sizeof (siginfo
))
4793 len
= sizeof (siginfo
) - offset
;
4795 if (readbuf
!= NULL
)
4796 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4799 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4801 /* Convert back to ptrace layout before flushing it out. */
4802 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4804 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
4811 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4812 so we notice when children change state; as the handler for the
4813 sigsuspend in my_waitpid. */
4816 sigchld_handler (int signo
)
4818 int old_errno
= errno
;
4824 /* fprintf is not async-signal-safe, so call write
4826 if (write (2, "sigchld_handler\n",
4827 sizeof ("sigchld_handler\n") - 1) < 0)
4828 break; /* just ignore */
4832 if (target_is_async_p ())
4833 async_file_mark (); /* trigger a linux_wait */
4839 linux_supports_non_stop (void)
4845 linux_async (int enable
)
4847 int previous
= (linux_event_pipe
[0] != -1);
4850 fprintf (stderr
, "linux_async (%d), previous=%d\n",
4853 if (previous
!= enable
)
4856 sigemptyset (&mask
);
4857 sigaddset (&mask
, SIGCHLD
);
4859 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
4863 if (pipe (linux_event_pipe
) == -1)
4864 fatal ("creating event pipe failed.");
4866 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
4867 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
4869 /* Register the event loop handler. */
4870 add_file_handler (linux_event_pipe
[0],
4871 handle_target_event
, NULL
);
4873 /* Always trigger a linux_wait. */
4878 delete_file_handler (linux_event_pipe
[0]);
4880 close (linux_event_pipe
[0]);
4881 close (linux_event_pipe
[1]);
4882 linux_event_pipe
[0] = -1;
4883 linux_event_pipe
[1] = -1;
4886 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
4893 linux_start_non_stop (int nonstop
)
4895 /* Register or unregister from event-loop accordingly. */
4896 linux_async (nonstop
);
4901 linux_supports_multi_process (void)
4907 linux_supports_disable_randomization (void)
4909 #ifdef HAVE_PERSONALITY
4917 linux_supports_agent (void)
4923 linux_supports_range_stepping (void)
4925 if (*the_low_target
.supports_range_stepping
== NULL
)
4928 return (*the_low_target
.supports_range_stepping
) ();
4931 /* Enumerate spufs IDs for process PID. */
4933 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
4939 struct dirent
*entry
;
4941 sprintf (path
, "/proc/%ld/fd", pid
);
4942 dir
= opendir (path
);
4947 while ((entry
= readdir (dir
)) != NULL
)
4953 fd
= atoi (entry
->d_name
);
4957 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
4958 if (stat (path
, &st
) != 0)
4960 if (!S_ISDIR (st
.st_mode
))
4963 if (statfs (path
, &stfs
) != 0)
4965 if (stfs
.f_type
!= SPUFS_MAGIC
)
4968 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
4970 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
4980 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
4981 object type, using the /proc file system. */
4983 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
4984 unsigned const char *writebuf
,
4985 CORE_ADDR offset
, int len
)
4987 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
4992 if (!writebuf
&& !readbuf
)
5000 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5003 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
5004 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5009 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5016 ret
= write (fd
, writebuf
, (size_t) len
);
5018 ret
= read (fd
, readbuf
, (size_t) len
);
5024 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5025 struct target_loadseg
5027 /* Core address to which the segment is mapped. */
5029 /* VMA recorded in the program header. */
5031 /* Size of this segment in memory. */
5035 # if defined PT_GETDSBT
5036 struct target_loadmap
5038 /* Protocol version number, must be zero. */
5040 /* Pointer to the DSBT table, its size, and the DSBT index. */
5041 unsigned *dsbt_table
;
5042 unsigned dsbt_size
, dsbt_index
;
5043 /* Number of segments in this map. */
5045 /* The actual memory map. */
5046 struct target_loadseg segs
[/*nsegs*/];
5048 # define LINUX_LOADMAP PT_GETDSBT
5049 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5050 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5052 struct target_loadmap
5054 /* Protocol version number, must be zero. */
5056 /* Number of segments in this map. */
5058 /* The actual memory map. */
5059 struct target_loadseg segs
[/*nsegs*/];
5061 # define LINUX_LOADMAP PTRACE_GETFDPIC
5062 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5063 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5067 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
5068 unsigned char *myaddr
, unsigned int len
)
5070 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
5072 struct target_loadmap
*data
= NULL
;
5073 unsigned int actual_length
, copy_length
;
5075 if (strcmp (annex
, "exec") == 0)
5076 addr
= (int) LINUX_LOADMAP_EXEC
;
5077 else if (strcmp (annex
, "interp") == 0)
5078 addr
= (int) LINUX_LOADMAP_INTERP
;
5082 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
5088 actual_length
= sizeof (struct target_loadmap
)
5089 + sizeof (struct target_loadseg
) * data
->nsegs
;
5091 if (offset
< 0 || offset
> actual_length
)
5094 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
5095 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
5099 # define linux_read_loadmap NULL
5100 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5103 linux_process_qsupported (const char *query
)
5105 if (the_low_target
.process_qsupported
!= NULL
)
5106 the_low_target
.process_qsupported (query
);
5110 linux_supports_tracepoints (void)
5112 if (*the_low_target
.supports_tracepoints
== NULL
)
5115 return (*the_low_target
.supports_tracepoints
) ();
5119 linux_read_pc (struct regcache
*regcache
)
5121 if (the_low_target
.get_pc
== NULL
)
5124 return (*the_low_target
.get_pc
) (regcache
);
5128 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
5130 gdb_assert (the_low_target
.set_pc
!= NULL
);
5132 (*the_low_target
.set_pc
) (regcache
, pc
);
5136 linux_thread_stopped (struct thread_info
*thread
)
5138 return get_thread_lwp (thread
)->stopped
;
5141 /* This exposes stop-all-threads functionality to other modules. */
5144 linux_pause_all (int freeze
)
5146 stop_all_lwps (freeze
, NULL
);
5149 /* This exposes unstop-all-threads functionality to other gdbserver
5153 linux_unpause_all (int unfreeze
)
5155 unstop_all_lwps (unfreeze
, NULL
);
5159 linux_prepare_to_access_memory (void)
5161 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5164 linux_pause_all (1);
5169 linux_done_accessing_memory (void)
5171 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5174 linux_unpause_all (1);
5178 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5179 CORE_ADDR collector
,
5182 CORE_ADDR
*jump_entry
,
5183 CORE_ADDR
*trampoline
,
5184 ULONGEST
*trampoline_size
,
5185 unsigned char *jjump_pad_insn
,
5186 ULONGEST
*jjump_pad_insn_size
,
5187 CORE_ADDR
*adjusted_insn_addr
,
5188 CORE_ADDR
*adjusted_insn_addr_end
,
5191 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5192 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5193 jump_entry
, trampoline
, trampoline_size
,
5194 jjump_pad_insn
, jjump_pad_insn_size
,
5195 adjusted_insn_addr
, adjusted_insn_addr_end
,
5199 static struct emit_ops
*
5200 linux_emit_ops (void)
5202 if (the_low_target
.emit_ops
!= NULL
)
5203 return (*the_low_target
.emit_ops
) ();
5209 linux_get_min_fast_tracepoint_insn_len (void)
5211 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5214 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5217 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5218 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5220 char filename
[PATH_MAX
];
5222 const int auxv_size
= is_elf64
5223 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5224 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5226 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5228 fd
= open (filename
, O_RDONLY
);
5234 while (read (fd
, buf
, auxv_size
) == auxv_size
5235 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5239 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5241 switch (aux
->a_type
)
5244 *phdr_memaddr
= aux
->a_un
.a_val
;
5247 *num_phdr
= aux
->a_un
.a_val
;
5253 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5255 switch (aux
->a_type
)
5258 *phdr_memaddr
= aux
->a_un
.a_val
;
5261 *num_phdr
= aux
->a_un
.a_val
;
5269 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5271 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5272 "phdr_memaddr = %ld, phdr_num = %d",
5273 (long) *phdr_memaddr
, *num_phdr
);
5280 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5283 get_dynamic (const int pid
, const int is_elf64
)
5285 CORE_ADDR phdr_memaddr
, relocation
;
5287 unsigned char *phdr_buf
;
5288 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5290 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5293 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5294 phdr_buf
= alloca (num_phdr
* phdr_size
);
5296 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5299 /* Compute relocation: it is expected to be 0 for "regular" executables,
5300 non-zero for PIE ones. */
5302 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5305 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5307 if (p
->p_type
== PT_PHDR
)
5308 relocation
= phdr_memaddr
- p
->p_vaddr
;
5312 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5314 if (p
->p_type
== PT_PHDR
)
5315 relocation
= phdr_memaddr
- p
->p_vaddr
;
5318 if (relocation
== -1)
5320 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5321 any real world executables, including PIE executables, have always
5322 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5323 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5324 or present DT_DEBUG anyway (fpc binaries are statically linked).
5326 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5328 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5333 for (i
= 0; i
< num_phdr
; i
++)
5337 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5339 if (p
->p_type
== PT_DYNAMIC
)
5340 return p
->p_vaddr
+ relocation
;
5344 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5346 if (p
->p_type
== PT_DYNAMIC
)
5347 return p
->p_vaddr
+ relocation
;
5354 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5355 can be 0 if the inferior does not yet have the library list initialized.
5356 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
5357 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
5360 get_r_debug (const int pid
, const int is_elf64
)
5362 CORE_ADDR dynamic_memaddr
;
5363 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5364 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5367 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5368 if (dynamic_memaddr
== 0)
5371 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5375 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5376 #ifdef DT_MIPS_RLD_MAP
5380 unsigned char buf
[sizeof (Elf64_Xword
)];
5384 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5386 if (linux_read_memory (dyn
->d_un
.d_val
,
5387 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5392 #endif /* DT_MIPS_RLD_MAP */
5394 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5395 map
= dyn
->d_un
.d_val
;
5397 if (dyn
->d_tag
== DT_NULL
)
5402 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5403 #ifdef DT_MIPS_RLD_MAP
5407 unsigned char buf
[sizeof (Elf32_Word
)];
5411 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5413 if (linux_read_memory (dyn
->d_un
.d_val
,
5414 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5419 #endif /* DT_MIPS_RLD_MAP */
5421 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5422 map
= dyn
->d_un
.d_val
;
5424 if (dyn
->d_tag
== DT_NULL
)
5428 dynamic_memaddr
+= dyn_size
;
5434 /* Read one pointer from MEMADDR in the inferior. */
5437 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5441 /* Go through a union so this works on either big or little endian
5442 hosts, when the inferior's pointer size is smaller than the size
5443 of CORE_ADDR. It is assumed the inferior's endianness is the
5444 same of the superior's. */
5447 CORE_ADDR core_addr
;
5452 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
5455 if (ptr_size
== sizeof (CORE_ADDR
))
5456 *ptr
= addr
.core_addr
;
5457 else if (ptr_size
== sizeof (unsigned int))
5460 gdb_assert_not_reached ("unhandled pointer size");
5465 struct link_map_offsets
5467 /* Offset and size of r_debug.r_version. */
5468 int r_version_offset
;
5470 /* Offset and size of r_debug.r_map. */
5473 /* Offset to l_addr field in struct link_map. */
5476 /* Offset to l_name field in struct link_map. */
5479 /* Offset to l_ld field in struct link_map. */
5482 /* Offset to l_next field in struct link_map. */
5485 /* Offset to l_prev field in struct link_map. */
5489 /* Construct qXfer:libraries-svr4:read reply. */
5492 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5493 unsigned const char *writebuf
,
5494 CORE_ADDR offset
, int len
)
5497 unsigned document_len
;
5498 struct process_info_private
*const priv
= current_process ()->private;
5499 char filename
[PATH_MAX
];
5502 static const struct link_map_offsets lmo_32bit_offsets
=
5504 0, /* r_version offset. */
5505 4, /* r_debug.r_map offset. */
5506 0, /* l_addr offset in link_map. */
5507 4, /* l_name offset in link_map. */
5508 8, /* l_ld offset in link_map. */
5509 12, /* l_next offset in link_map. */
5510 16 /* l_prev offset in link_map. */
5513 static const struct link_map_offsets lmo_64bit_offsets
=
5515 0, /* r_version offset. */
5516 8, /* r_debug.r_map offset. */
5517 0, /* l_addr offset in link_map. */
5518 8, /* l_name offset in link_map. */
5519 16, /* l_ld offset in link_map. */
5520 24, /* l_next offset in link_map. */
5521 32 /* l_prev offset in link_map. */
5523 const struct link_map_offsets
*lmo
;
5524 unsigned int machine
;
5526 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
5527 int allocated
= 1024;
5529 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5530 int header_done
= 0;
5532 if (writebuf
!= NULL
)
5534 if (readbuf
== NULL
)
5537 pid
= lwpid_of (get_thread_lwp (current_inferior
));
5538 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5539 is_elf64
= elf_64_file_p (filename
, &machine
);
5540 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5541 ptr_size
= is_elf64
? 8 : 4;
5543 while (annex
[0] != '\0')
5549 sep
= strchr (annex
, '=');
5554 if (len
== 5 && strncmp (annex
, "start", 5) == 0)
5556 else if (len
== 4 && strncmp (annex
, "prev", 4) == 0)
5560 annex
= strchr (sep
, ';');
5567 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
5574 if (priv
->r_debug
== 0)
5575 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5577 /* We failed to find DT_DEBUG. Such situation will not change
5578 for this inferior - do not retry it. Report it to GDB as
5579 E01, see for the reasons at the GDB solib-svr4.c side. */
5580 if (priv
->r_debug
== (CORE_ADDR
) -1)
5583 if (priv
->r_debug
!= 0)
5585 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5586 (unsigned char *) &r_version
,
5587 sizeof (r_version
)) != 0
5590 warning ("unexpected r_debug version %d", r_version
);
5592 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5593 &lm_addr
, ptr_size
) != 0)
5595 warning ("unable to read r_map from 0x%lx",
5596 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5601 document
= xmalloc (allocated
);
5602 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5603 p
= document
+ strlen (document
);
5606 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5607 &l_name
, ptr_size
) == 0
5608 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5609 &l_addr
, ptr_size
) == 0
5610 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5611 &l_ld
, ptr_size
) == 0
5612 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5613 &l_prev
, ptr_size
) == 0
5614 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5615 &l_next
, ptr_size
) == 0)
5617 unsigned char libname
[PATH_MAX
];
5619 if (lm_prev
!= l_prev
)
5621 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5622 (long) lm_prev
, (long) l_prev
);
5626 /* Ignore the first entry even if it has valid name as the first entry
5627 corresponds to the main executable. The first entry should not be
5628 skipped if the dynamic loader was loaded late by a static executable
5629 (see solib-svr4.c parameter ignore_first). But in such case the main
5630 executable does not have PT_DYNAMIC present and this function already
5631 exited above due to failed get_r_debug. */
5634 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5639 /* Not checking for error because reading may stop before
5640 we've got PATH_MAX worth of characters. */
5642 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5643 libname
[sizeof (libname
) - 1] = '\0';
5644 if (libname
[0] != '\0')
5646 /* 6x the size for xml_escape_text below. */
5647 size_t len
= 6 * strlen ((char *) libname
);
5652 /* Terminate `<library-list-svr4'. */
5657 while (allocated
< p
- document
+ len
+ 200)
5659 /* Expand to guarantee sufficient storage. */
5660 uintptr_t document_len
= p
- document
;
5662 document
= xrealloc (document
, 2 * allocated
);
5664 p
= document
+ document_len
;
5667 name
= xml_escape_text ((char *) libname
);
5668 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
5669 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5670 name
, (unsigned long) lm_addr
,
5671 (unsigned long) l_addr
, (unsigned long) l_ld
);
5682 /* Empty list; terminate `<library-list-svr4'. */
5686 strcpy (p
, "</library-list-svr4>");
5688 document_len
= strlen (document
);
5689 if (offset
< document_len
)
5690 document_len
-= offset
;
5693 if (len
> document_len
)
5696 memcpy (readbuf
, document
+ offset
, len
);
5702 #ifdef HAVE_LINUX_BTRACE
5704 /* Enable branch tracing. */
5706 static struct btrace_target_info
*
5707 linux_low_enable_btrace (ptid_t ptid
)
5709 struct btrace_target_info
*tinfo
;
5711 tinfo
= linux_enable_btrace (ptid
);
5715 struct thread_info
*thread
= find_thread_ptid (ptid
);
5716 struct regcache
*regcache
= get_thread_regcache (thread
, 0);
5718 tinfo
->ptr_bits
= register_size (regcache
->tdesc
, 0) * 8;
5724 /* Read branch trace data as btrace xml document. */
5727 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
5730 VEC (btrace_block_s
) *btrace
;
5731 struct btrace_block
*block
;
5734 btrace
= linux_read_btrace (tinfo
, type
);
5736 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
5737 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
5739 for (i
= 0; VEC_iterate (btrace_block_s
, btrace
, i
, block
); i
++)
5740 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
5741 paddress (block
->begin
), paddress (block
->end
));
5743 buffer_grow_str (buffer
, "</btrace>\n");
5745 VEC_free (btrace_block_s
, btrace
);
5747 #endif /* HAVE_LINUX_BTRACE */
5749 static struct target_ops linux_target_ops
= {
5750 linux_create_inferior
,
5759 linux_fetch_registers
,
5760 linux_store_registers
,
5761 linux_prepare_to_access_memory
,
5762 linux_done_accessing_memory
,
5765 linux_look_up_symbols
,
5766 linux_request_interrupt
,
5770 linux_stopped_by_watchpoint
,
5771 linux_stopped_data_address
,
5772 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5773 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5774 && defined(PT_TEXT_END_ADDR)
5779 #ifdef USE_THREAD_DB
5780 thread_db_get_tls_address
,
5785 hostio_last_error_from_errno
,
5788 linux_supports_non_stop
,
5790 linux_start_non_stop
,
5791 linux_supports_multi_process
,
5792 #ifdef USE_THREAD_DB
5793 thread_db_handle_monitor_command
,
5797 linux_common_core_of_thread
,
5799 linux_process_qsupported
,
5800 linux_supports_tracepoints
,
5803 linux_thread_stopped
,
5807 linux_cancel_breakpoints
,
5808 linux_stabilize_threads
,
5809 linux_install_fast_tracepoint_jump_pad
,
5811 linux_supports_disable_randomization
,
5812 linux_get_min_fast_tracepoint_insn_len
,
5813 linux_qxfer_libraries_svr4
,
5814 linux_supports_agent
,
5815 #ifdef HAVE_LINUX_BTRACE
5816 linux_supports_btrace
,
5817 linux_low_enable_btrace
,
5818 linux_disable_btrace
,
5819 linux_low_read_btrace
,
5826 linux_supports_range_stepping
,
5830 linux_init_signals ()
5832 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5833 to find what the cancel signal actually is. */
5834 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
5835 signal (__SIGRTMIN
+1, SIG_IGN
);
5839 #ifdef HAVE_LINUX_REGSETS
5841 initialize_regsets_info (struct regsets_info
*info
)
5843 for (info
->num_regsets
= 0;
5844 info
->regsets
[info
->num_regsets
].size
>= 0;
5845 info
->num_regsets
++)
5851 initialize_low (void)
5853 struct sigaction sigchld_action
;
5854 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
5855 set_target_ops (&linux_target_ops
);
5856 set_breakpoint_data (the_low_target
.breakpoint
,
5857 the_low_target
.breakpoint_len
);
5858 linux_init_signals ();
5859 linux_ptrace_init_warnings ();
5861 sigchld_action
.sa_handler
= sigchld_handler
;
5862 sigemptyset (&sigchld_action
.sa_mask
);
5863 sigchld_action
.sa_flags
= SA_RESTART
;
5864 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
5866 initialize_low_arch ();