1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2014 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"
51 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
52 then ELFMAG0 will have been defined. If it didn't get included by
53 gdb_proc_service.h then including it will likely introduce a duplicate
54 definition of elf_fpregset_t. */
59 #define SPUFS_MAGIC 0x23c9b64e
62 #ifdef HAVE_PERSONALITY
63 # include <sys/personality.h>
64 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
65 # define ADDR_NO_RANDOMIZE 0x0040000
74 #define W_STOPCODE(sig) ((sig) << 8 | 0x7f)
77 /* This is the kernel's hard limit. Not to be confused with
83 /* Some targets did not define these ptrace constants from the start,
84 so gdbserver defines them locally here. In the future, these may
85 be removed after they are added to asm/ptrace.h. */
86 #if !(defined(PT_TEXT_ADDR) \
87 || defined(PT_DATA_ADDR) \
88 || defined(PT_TEXT_END_ADDR))
89 #if defined(__mcoldfire__)
90 /* These are still undefined in 3.10 kernels. */
91 #define PT_TEXT_ADDR 49*4
92 #define PT_DATA_ADDR 50*4
93 #define PT_TEXT_END_ADDR 51*4
94 /* BFIN already defines these since at least 2.6.32 kernels. */
96 #define PT_TEXT_ADDR 220
97 #define PT_TEXT_END_ADDR 224
98 #define PT_DATA_ADDR 228
99 /* These are still undefined in 3.10 kernels. */
100 #elif defined(__TMS320C6X__)
101 #define PT_TEXT_ADDR (0x10000*4)
102 #define PT_DATA_ADDR (0x10004*4)
103 #define PT_TEXT_END_ADDR (0x10008*4)
107 #ifdef HAVE_LINUX_BTRACE
108 # include "linux-btrace.h"
111 #ifndef HAVE_ELF32_AUXV_T
112 /* Copied from glibc's elf.h. */
115 uint32_t a_type
; /* Entry type */
118 uint32_t a_val
; /* Integer value */
119 /* We use to have pointer elements added here. We cannot do that,
120 though, since it does not work when using 32-bit definitions
121 on 64-bit platforms and vice versa. */
126 #ifndef HAVE_ELF64_AUXV_T
127 /* Copied from glibc's elf.h. */
130 uint64_t a_type
; /* Entry type */
133 uint64_t a_val
; /* Integer value */
134 /* We use to have pointer elements added here. We cannot do that,
135 though, since it does not work when using 32-bit definitions
136 on 64-bit platforms and vice versa. */
141 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
142 representation of the thread ID.
144 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
145 the same as the LWP ID.
147 ``all_processes'' is keyed by the "overall process ID", which
148 GNU/Linux calls tgid, "thread group ID". */
150 struct inferior_list all_lwps
;
152 /* A list of all unknown processes which receive stop signals. Some
153 other process will presumably claim each of these as forked
154 children momentarily. */
156 struct simple_pid_list
158 /* The process ID. */
161 /* The status as reported by waitpid. */
165 struct simple_pid_list
*next
;
167 struct simple_pid_list
*stopped_pids
;
169 /* Trivial list manipulation functions to keep track of a list of new
170 stopped processes. */
173 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
175 struct simple_pid_list
*new_pid
= xmalloc (sizeof (struct simple_pid_list
));
178 new_pid
->status
= status
;
179 new_pid
->next
= *listp
;
184 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
186 struct simple_pid_list
**p
;
188 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
189 if ((*p
)->pid
== pid
)
191 struct simple_pid_list
*next
= (*p
)->next
;
193 *statusp
= (*p
)->status
;
201 enum stopping_threads_kind
203 /* Not stopping threads presently. */
204 NOT_STOPPING_THREADS
,
206 /* Stopping threads. */
209 /* Stopping and suspending threads. */
210 STOPPING_AND_SUSPENDING_THREADS
213 /* This is set while stop_all_lwps is in effect. */
214 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
216 /* FIXME make into a target method? */
217 int using_threads
= 1;
219 /* True if we're presently stabilizing threads (moving them out of
221 static int stabilizing_threads
;
223 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
224 int step
, int signal
, siginfo_t
*info
);
225 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
226 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
227 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
228 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
229 static void *add_lwp (ptid_t ptid
);
230 static int linux_stopped_by_watchpoint (void);
231 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
232 static void proceed_all_lwps (void);
233 static int finish_step_over (struct lwp_info
*lwp
);
234 static CORE_ADDR
get_stop_pc (struct lwp_info
*lwp
);
235 static int kill_lwp (unsigned long lwpid
, int signo
);
237 /* True if the low target can hardware single-step. Such targets
238 don't need a BREAKPOINT_REINSERT_ADDR callback. */
241 can_hardware_single_step (void)
243 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
246 /* True if the low target supports memory breakpoints. If so, we'll
247 have a GET_PC implementation. */
250 supports_breakpoints (void)
252 return (the_low_target
.get_pc
!= NULL
);
255 /* Returns true if this target can support fast tracepoints. This
256 does not mean that the in-process agent has been loaded in the
260 supports_fast_tracepoints (void)
262 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
265 /* True if LWP is stopped in its stepping range. */
268 lwp_in_step_range (struct lwp_info
*lwp
)
270 CORE_ADDR pc
= lwp
->stop_pc
;
272 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
275 struct pending_signals
279 struct pending_signals
*prev
;
282 /* The read/write ends of the pipe registered as waitable file in the
284 static int linux_event_pipe
[2] = { -1, -1 };
286 /* True if we're currently in async mode. */
287 #define target_is_async_p() (linux_event_pipe[0] != -1)
289 static void send_sigstop (struct lwp_info
*lwp
);
290 static void wait_for_sigstop (struct inferior_list_entry
*entry
);
292 /* Return non-zero if HEADER is a 64-bit ELF file. */
295 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
297 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
298 && header
->e_ident
[EI_MAG1
] == ELFMAG1
299 && header
->e_ident
[EI_MAG2
] == ELFMAG2
300 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
302 *machine
= header
->e_machine
;
303 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
310 /* Return non-zero if FILE is a 64-bit ELF file,
311 zero if the file is not a 64-bit ELF file,
312 and -1 if the file is not accessible or doesn't exist. */
315 elf_64_file_p (const char *file
, unsigned int *machine
)
320 fd
= open (file
, O_RDONLY
);
324 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
331 return elf_64_header_p (&header
, machine
);
334 /* Accepts an integer PID; Returns true if the executable PID is
335 running is a 64-bit ELF file.. */
338 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
342 sprintf (file
, "/proc/%d/exe", pid
);
343 return elf_64_file_p (file
, machine
);
347 delete_lwp (struct lwp_info
*lwp
)
349 remove_thread (get_lwp_thread (lwp
));
350 remove_inferior (&all_lwps
, &lwp
->head
);
351 free (lwp
->arch_private
);
355 /* Add a process to the common process list, and set its private
358 static struct process_info
*
359 linux_add_process (int pid
, int attached
)
361 struct process_info
*proc
;
363 proc
= add_process (pid
, attached
);
364 proc
->private = xcalloc (1, sizeof (*proc
->private));
366 /* Set the arch when the first LWP stops. */
367 proc
->private->new_inferior
= 1;
369 if (the_low_target
.new_process
!= NULL
)
370 proc
->private->arch_private
= the_low_target
.new_process ();
375 /* Handle a GNU/Linux extended wait response. If we see a clone
376 event, we need to add the new LWP to our list (and not report the
377 trap to higher layers). */
380 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
382 int event
= wstat
>> 16;
383 struct lwp_info
*new_lwp
;
385 if (event
== PTRACE_EVENT_CLONE
)
388 unsigned long new_pid
;
391 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_child
), (PTRACE_TYPE_ARG3
) 0,
394 /* If we haven't already seen the new PID stop, wait for it now. */
395 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
397 /* The new child has a pending SIGSTOP. We can't affect it until it
398 hits the SIGSTOP, but we're already attached. */
400 ret
= my_waitpid (new_pid
, &status
, __WALL
);
403 perror_with_name ("waiting for new child");
404 else if (ret
!= new_pid
)
405 warning ("wait returned unexpected PID %d", ret
);
406 else if (!WIFSTOPPED (status
))
407 warning ("wait returned unexpected status 0x%x", status
);
410 ptid
= ptid_build (pid_of (event_child
), new_pid
, 0);
411 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
412 add_thread (ptid
, new_lwp
);
414 /* Either we're going to immediately resume the new thread
415 or leave it stopped. linux_resume_one_lwp is a nop if it
416 thinks the thread is currently running, so set this first
417 before calling linux_resume_one_lwp. */
418 new_lwp
->stopped
= 1;
420 /* If we're suspending all threads, leave this one suspended
422 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
423 new_lwp
->suspended
= 1;
425 /* Normally we will get the pending SIGSTOP. But in some cases
426 we might get another signal delivered to the group first.
427 If we do get another signal, be sure not to lose it. */
428 if (WSTOPSIG (status
) == SIGSTOP
)
430 if (stopping_threads
!= NOT_STOPPING_THREADS
)
431 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
433 linux_resume_one_lwp (new_lwp
, 0, 0, NULL
);
437 new_lwp
->stop_expected
= 1;
439 if (stopping_threads
!= NOT_STOPPING_THREADS
)
441 new_lwp
->stop_pc
= get_stop_pc (new_lwp
);
442 new_lwp
->status_pending_p
= 1;
443 new_lwp
->status_pending
= status
;
446 /* Pass the signal on. This is what GDB does - except
447 shouldn't we really report it instead? */
448 linux_resume_one_lwp (new_lwp
, 0, WSTOPSIG (status
), NULL
);
451 /* Always resume the current thread. If we are stopping
452 threads, it will have a pending SIGSTOP; we may as well
454 linux_resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
458 /* Return the PC as read from the regcache of LWP, without any
462 get_pc (struct lwp_info
*lwp
)
464 struct thread_info
*saved_inferior
;
465 struct regcache
*regcache
;
468 if (the_low_target
.get_pc
== NULL
)
471 saved_inferior
= current_inferior
;
472 current_inferior
= get_lwp_thread (lwp
);
474 regcache
= get_thread_regcache (current_inferior
, 1);
475 pc
= (*the_low_target
.get_pc
) (regcache
);
478 fprintf (stderr
, "pc is 0x%lx\n", (long) pc
);
480 current_inferior
= saved_inferior
;
484 /* This function should only be called if LWP got a SIGTRAP.
485 The SIGTRAP could mean several things.
487 On i386, where decr_pc_after_break is non-zero:
488 If we were single-stepping this process using PTRACE_SINGLESTEP,
489 we will get only the one SIGTRAP (even if the instruction we
490 stepped over was a breakpoint). The value of $eip will be the
492 If we continue the process using PTRACE_CONT, we will get a
493 SIGTRAP when we hit a breakpoint. The value of $eip will be
494 the instruction after the breakpoint (i.e. needs to be
495 decremented). If we report the SIGTRAP to GDB, we must also
496 report the undecremented PC. If we cancel the SIGTRAP, we
497 must resume at the decremented PC.
499 (Presumably, not yet tested) On a non-decr_pc_after_break machine
500 with hardware or kernel single-step:
501 If we single-step over a breakpoint instruction, our PC will
502 point at the following instruction. If we continue and hit a
503 breakpoint instruction, our PC will point at the breakpoint
507 get_stop_pc (struct lwp_info
*lwp
)
511 if (the_low_target
.get_pc
== NULL
)
514 stop_pc
= get_pc (lwp
);
516 if (WSTOPSIG (lwp
->last_status
) == SIGTRAP
518 && !lwp
->stopped_by_watchpoint
519 && lwp
->last_status
>> 16 == 0)
520 stop_pc
-= the_low_target
.decr_pc_after_break
;
523 fprintf (stderr
, "stop pc is 0x%lx\n", (long) stop_pc
);
529 add_lwp (ptid_t ptid
)
531 struct lwp_info
*lwp
;
533 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
534 memset (lwp
, 0, sizeof (*lwp
));
538 if (the_low_target
.new_thread
!= NULL
)
539 lwp
->arch_private
= the_low_target
.new_thread ();
541 add_inferior_to_list (&all_lwps
, &lwp
->head
);
546 /* Start an inferior process and returns its pid.
547 ALLARGS is a vector of program-name and args. */
550 linux_create_inferior (char *program
, char **allargs
)
552 #ifdef HAVE_PERSONALITY
553 int personality_orig
= 0, personality_set
= 0;
555 struct lwp_info
*new_lwp
;
559 #ifdef HAVE_PERSONALITY
560 if (disable_randomization
)
563 personality_orig
= personality (0xffffffff);
564 if (errno
== 0 && !(personality_orig
& ADDR_NO_RANDOMIZE
))
567 personality (personality_orig
| ADDR_NO_RANDOMIZE
);
569 if (errno
!= 0 || (personality_set
570 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE
)))
571 warning ("Error disabling address space randomization: %s",
576 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
582 perror_with_name ("fork");
587 ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
589 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
590 signal (__SIGRTMIN
+ 1, SIG_DFL
);
595 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
596 stdout to stderr so that inferior i/o doesn't corrupt the connection.
597 Also, redirect stdin to /dev/null. */
598 if (remote_connection_is_stdio ())
601 open ("/dev/null", O_RDONLY
);
603 if (write (2, "stdin/stdout redirected\n",
604 sizeof ("stdin/stdout redirected\n") - 1) < 0)
606 /* Errors ignored. */;
610 execv (program
, allargs
);
612 execvp (program
, allargs
);
614 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
620 #ifdef HAVE_PERSONALITY
624 personality (personality_orig
);
626 warning ("Error restoring address space randomization: %s",
631 linux_add_process (pid
, 0);
633 ptid
= ptid_build (pid
, pid
, 0);
634 new_lwp
= add_lwp (ptid
);
635 add_thread (ptid
, new_lwp
);
636 new_lwp
->must_set_ptrace_flags
= 1;
641 /* Attach to an inferior process. */
644 linux_attach_lwp_1 (unsigned long lwpid
, int initial
)
647 struct lwp_info
*new_lwp
;
649 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
652 struct buffer buffer
;
656 /* If we fail to attach to an LWP, just warn. */
657 fprintf (stderr
, "Cannot attach to lwp %ld: %s (%d)\n", lwpid
,
658 strerror (errno
), errno
);
663 /* If we fail to attach to a process, report an error. */
664 buffer_init (&buffer
);
665 linux_ptrace_attach_warnings (lwpid
, &buffer
);
666 buffer_grow_str0 (&buffer
, "");
667 error ("%sCannot attach to lwp %ld: %s (%d)", buffer_finish (&buffer
),
668 lwpid
, strerror (errno
), errno
);
672 /* If lwp is the tgid, we handle adding existing threads later.
673 Otherwise we just add lwp without bothering about any other
675 ptid
= ptid_build (lwpid
, lwpid
, 0);
678 /* Note that extracting the pid from the current inferior is
679 safe, since we're always called in the context of the same
680 process as this new thread. */
681 int pid
= pid_of (get_thread_lwp (current_inferior
));
682 ptid
= ptid_build (pid
, lwpid
, 0);
685 new_lwp
= (struct lwp_info
*) add_lwp (ptid
);
686 add_thread (ptid
, new_lwp
);
688 /* We need to wait for SIGSTOP before being able to make the next
689 ptrace call on this LWP. */
690 new_lwp
->must_set_ptrace_flags
= 1;
692 if (linux_proc_pid_is_stopped (lwpid
))
696 "Attached to a stopped process\n");
698 /* The process is definitely stopped. It is in a job control
699 stop, unless the kernel predates the TASK_STOPPED /
700 TASK_TRACED distinction, in which case it might be in a
701 ptrace stop. Make sure it is in a ptrace stop; from there we
702 can kill it, signal it, et cetera.
704 First make sure there is a pending SIGSTOP. Since we are
705 already attached, the process can not transition from stopped
706 to running without a PTRACE_CONT; so we know this signal will
707 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
708 probably already in the queue (unless this kernel is old
709 enough to use TASK_STOPPED for ptrace stops); but since
710 SIGSTOP is not an RT signal, it can only be queued once. */
711 kill_lwp (lwpid
, SIGSTOP
);
713 /* Finally, resume the stopped process. This will deliver the
714 SIGSTOP (or a higher priority signal, just like normal
715 PTRACE_ATTACH), which we'll catch later on. */
716 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
719 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
722 There are several cases to consider here:
724 1) gdbserver has already attached to the process and is being notified
725 of a new thread that is being created.
726 In this case we should ignore that SIGSTOP and resume the
727 process. This is handled below by setting stop_expected = 1,
728 and the fact that add_thread sets last_resume_kind ==
731 2) This is the first thread (the process thread), and we're attaching
732 to it via attach_inferior.
733 In this case we want the process thread to stop.
734 This is handled by having linux_attach set last_resume_kind ==
735 resume_stop after we return.
737 If the pid we are attaching to is also the tgid, we attach to and
738 stop all the existing threads. Otherwise, we attach to pid and
739 ignore any other threads in the same group as this pid.
741 3) GDB is connecting to gdbserver and is requesting an enumeration of all
743 In this case we want the thread to stop.
744 FIXME: This case is currently not properly handled.
745 We should wait for the SIGSTOP but don't. Things work apparently
746 because enough time passes between when we ptrace (ATTACH) and when
747 gdb makes the next ptrace call on the thread.
749 On the other hand, if we are currently trying to stop all threads, we
750 should treat the new thread as if we had sent it a SIGSTOP. This works
751 because we are guaranteed that the add_lwp call above added us to the
752 end of the list, and so the new thread has not yet reached
753 wait_for_sigstop (but will). */
754 new_lwp
->stop_expected
= 1;
758 linux_attach_lwp (unsigned long lwpid
)
760 linux_attach_lwp_1 (lwpid
, 0);
763 /* Attach to PID. If PID is the tgid, attach to it and all
767 linux_attach (unsigned long pid
)
769 /* Attach to PID. We will check for other threads
771 linux_attach_lwp_1 (pid
, 1);
772 linux_add_process (pid
, 1);
776 struct thread_info
*thread
;
778 /* Don't ignore the initial SIGSTOP if we just attached to this
779 process. It will be collected by wait shortly. */
780 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
781 thread
->last_resume_kind
= resume_stop
;
784 if (linux_proc_get_tgid (pid
) == pid
)
789 sprintf (pathname
, "/proc/%ld/task", pid
);
791 dir
= opendir (pathname
);
795 fprintf (stderr
, "Could not open /proc/%ld/task.\n", pid
);
800 /* At this point we attached to the tgid. Scan the task for
803 int new_threads_found
;
807 while (iterations
< 2)
809 new_threads_found
= 0;
810 /* Add all the other threads. While we go through the
811 threads, new threads may be spawned. Cycle through
812 the list of threads until we have done two iterations without
813 finding new threads. */
814 while ((dp
= readdir (dir
)) != NULL
)
817 lwp
= strtoul (dp
->d_name
, NULL
, 10);
819 /* Is this a new thread? */
821 && find_thread_ptid (ptid_build (pid
, lwp
, 0)) == NULL
)
823 linux_attach_lwp_1 (lwp
, 0);
828 Found and attached to new lwp %ld\n", lwp
);
832 if (!new_threads_found
)
853 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
855 struct counter
*counter
= args
;
857 if (ptid_get_pid (entry
->id
) == counter
->pid
)
859 if (++counter
->count
> 1)
867 last_thread_of_process_p (struct thread_info
*thread
)
869 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
870 int pid
= ptid_get_pid (ptid
);
871 struct counter counter
= { pid
, 0 };
873 return (find_inferior (&all_threads
,
874 second_thread_of_pid_p
, &counter
) == NULL
);
880 linux_kill_one_lwp (struct lwp_info
*lwp
)
882 int pid
= lwpid_of (lwp
);
884 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
885 there is no signal context, and ptrace(PTRACE_KILL) (or
886 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
887 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
888 alternative is to kill with SIGKILL. We only need one SIGKILL
889 per process, not one for each thread. But since we still support
890 linuxthreads, and we also support debugging programs using raw
891 clone without CLONE_THREAD, we send one for each thread. For
892 years, we used PTRACE_KILL only, so we're being a bit paranoid
893 about some old kernels where PTRACE_KILL might work better
894 (dubious if there are any such, but that's why it's paranoia), so
895 we try SIGKILL first, PTRACE_KILL second, and so we're fine
902 "LKL: kill (SIGKILL) %s, 0, 0 (%s)\n",
903 target_pid_to_str (ptid_of (lwp
)),
904 errno
? strerror (errno
) : "OK");
907 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
910 "LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
911 target_pid_to_str (ptid_of (lwp
)),
912 errno
? strerror (errno
) : "OK");
915 /* Callback for `find_inferior'. Kills an lwp of a given process,
916 except the leader. */
919 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
921 struct thread_info
*thread
= (struct thread_info
*) entry
;
922 struct lwp_info
*lwp
= get_thread_lwp (thread
);
924 int pid
= * (int *) args
;
926 if (ptid_get_pid (entry
->id
) != pid
)
929 /* We avoid killing the first thread here, because of a Linux kernel (at
930 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
931 the children get a chance to be reaped, it will remain a zombie
934 if (lwpid_of (lwp
) == pid
)
937 fprintf (stderr
, "lkop: is last of process %s\n",
938 target_pid_to_str (entry
->id
));
944 linux_kill_one_lwp (lwp
);
946 /* Make sure it died. The loop is most likely unnecessary. */
947 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
948 } while (pid
> 0 && WIFSTOPPED (wstat
));
956 struct process_info
*process
;
957 struct lwp_info
*lwp
;
961 process
= find_process_pid (pid
);
965 /* If we're killing a running inferior, make sure it is stopped
966 first, as PTRACE_KILL will not work otherwise. */
967 stop_all_lwps (0, NULL
);
969 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
971 /* See the comment in linux_kill_one_lwp. We did not kill the first
972 thread in the list, so do so now. */
973 lwp
= find_lwp_pid (pid_to_ptid (pid
));
978 fprintf (stderr
, "lk_1: cannot find lwp %ld, for pid: %d\n",
979 lwpid_of (lwp
), pid
);
984 fprintf (stderr
, "lk_1: killing lwp %ld, for pid: %d\n",
985 lwpid_of (lwp
), pid
);
989 linux_kill_one_lwp (lwp
);
991 /* Make sure it died. The loop is most likely unnecessary. */
992 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
993 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
996 the_target
->mourn (process
);
998 /* Since we presently can only stop all lwps of all processes, we
999 need to unstop lwps of other processes. */
1000 unstop_all_lwps (0, NULL
);
1004 /* Get pending signal of THREAD, for detaching purposes. This is the
1005 signal the thread last stopped for, which we need to deliver to the
1006 thread when detaching, otherwise, it'd be suppressed/lost. */
1009 get_detach_signal (struct thread_info
*thread
)
1011 enum gdb_signal signo
= GDB_SIGNAL_0
;
1013 struct lwp_info
*lp
= get_thread_lwp (thread
);
1015 if (lp
->status_pending_p
)
1016 status
= lp
->status_pending
;
1019 /* If the thread had been suspended by gdbserver, and it stopped
1020 cleanly, then it'll have stopped with SIGSTOP. But we don't
1021 want to deliver that SIGSTOP. */
1022 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1023 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1026 /* Otherwise, we may need to deliver the signal we
1028 status
= lp
->last_status
;
1031 if (!WIFSTOPPED (status
))
1035 "GPS: lwp %s hasn't stopped: no pending signal\n",
1036 target_pid_to_str (ptid_of (lp
)));
1040 /* Extended wait statuses aren't real SIGTRAPs. */
1041 if (WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
1045 "GPS: lwp %s had stopped with extended "
1046 "status: no pending signal\n",
1047 target_pid_to_str (ptid_of (lp
)));
1051 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1053 if (program_signals_p
&& !program_signals
[signo
])
1057 "GPS: lwp %s had signal %s, but it is in nopass state\n",
1058 target_pid_to_str (ptid_of (lp
)),
1059 gdb_signal_to_string (signo
));
1062 else if (!program_signals_p
1063 /* If we have no way to know which signals GDB does not
1064 want to have passed to the program, assume
1065 SIGTRAP/SIGINT, which is GDB's default. */
1066 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1070 "GPS: lwp %s had signal %s, "
1071 "but we don't know if we should pass it. Default to not.\n",
1072 target_pid_to_str (ptid_of (lp
)),
1073 gdb_signal_to_string (signo
));
1080 "GPS: lwp %s has pending signal %s: delivering it.\n",
1081 target_pid_to_str (ptid_of (lp
)),
1082 gdb_signal_to_string (signo
));
1084 return WSTOPSIG (status
);
1089 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1091 struct thread_info
*thread
= (struct thread_info
*) entry
;
1092 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1093 int pid
= * (int *) args
;
1096 if (ptid_get_pid (entry
->id
) != pid
)
1099 /* If there is a pending SIGSTOP, get rid of it. */
1100 if (lwp
->stop_expected
)
1104 "Sending SIGCONT to %s\n",
1105 target_pid_to_str (ptid_of (lwp
)));
1107 kill_lwp (lwpid_of (lwp
), SIGCONT
);
1108 lwp
->stop_expected
= 0;
1111 /* Flush any pending changes to the process's registers. */
1112 regcache_invalidate_thread (get_lwp_thread (lwp
));
1114 /* Pass on any pending signal for this thread. */
1115 sig
= get_detach_signal (thread
);
1117 /* Finally, let it resume. */
1118 if (the_low_target
.prepare_to_resume
!= NULL
)
1119 the_low_target
.prepare_to_resume (lwp
);
1120 if (ptrace (PTRACE_DETACH
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
1121 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1122 error (_("Can't detach %s: %s"),
1123 target_pid_to_str (ptid_of (lwp
)),
1131 linux_detach (int pid
)
1133 struct process_info
*process
;
1135 process
= find_process_pid (pid
);
1136 if (process
== NULL
)
1139 /* Stop all threads before detaching. First, ptrace requires that
1140 the thread is stopped to sucessfully detach. Second, thread_db
1141 may need to uninstall thread event breakpoints from memory, which
1142 only works with a stopped process anyway. */
1143 stop_all_lwps (0, NULL
);
1145 #ifdef USE_THREAD_DB
1146 thread_db_detach (process
);
1149 /* Stabilize threads (move out of jump pads). */
1150 stabilize_threads ();
1152 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1154 the_target
->mourn (process
);
1156 /* Since we presently can only stop all lwps of all processes, we
1157 need to unstop lwps of other processes. */
1158 unstop_all_lwps (0, NULL
);
1162 /* Remove all LWPs that belong to process PROC from the lwp list. */
1165 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1167 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1168 struct process_info
*process
= proc
;
1170 if (pid_of (lwp
) == pid_of (process
))
1177 linux_mourn (struct process_info
*process
)
1179 struct process_info_private
*priv
;
1181 #ifdef USE_THREAD_DB
1182 thread_db_mourn (process
);
1185 find_inferior (&all_lwps
, delete_lwp_callback
, process
);
1187 /* Freeing all private data. */
1188 priv
= process
->private;
1189 free (priv
->arch_private
);
1191 process
->private = NULL
;
1193 remove_process (process
);
1197 linux_join (int pid
)
1202 ret
= my_waitpid (pid
, &status
, 0);
1203 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1205 } while (ret
!= -1 || errno
!= ECHILD
);
1208 /* Return nonzero if the given thread is still alive. */
1210 linux_thread_alive (ptid_t ptid
)
1212 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1214 /* We assume we always know if a thread exits. If a whole process
1215 exited but we still haven't been able to report it to GDB, we'll
1216 hold on to the last lwp of the dead process. */
1223 /* Return 1 if this lwp has an interesting status pending. */
1225 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1227 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1228 ptid_t ptid
= * (ptid_t
*) arg
;
1229 struct thread_info
*thread
;
1231 /* Check if we're only interested in events from a specific process
1233 if (!ptid_equal (minus_one_ptid
, ptid
)
1234 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
1237 thread
= get_lwp_thread (lwp
);
1239 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1240 report any status pending the LWP may have. */
1241 if (thread
->last_resume_kind
== resume_stop
1242 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1245 return lwp
->status_pending_p
;
1249 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1251 ptid_t ptid
= *(ptid_t
*) data
;
1254 if (ptid_get_lwp (ptid
) != 0)
1255 lwp
= ptid_get_lwp (ptid
);
1257 lwp
= ptid_get_pid (ptid
);
1259 if (ptid_get_lwp (entry
->id
) == lwp
)
1266 find_lwp_pid (ptid_t ptid
)
1268 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
1271 static struct lwp_info
*
1272 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
1275 int to_wait_for
= -1;
1276 struct lwp_info
*child
= NULL
;
1279 fprintf (stderr
, "linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1281 if (ptid_equal (ptid
, minus_one_ptid
))
1282 to_wait_for
= -1; /* any child */
1284 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1290 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1291 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1294 perror_with_name ("waitpid");
1297 && (!WIFSTOPPED (*wstatp
)
1298 || (WSTOPSIG (*wstatp
) != 32
1299 && WSTOPSIG (*wstatp
) != 33)))
1300 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
1302 child
= find_lwp_pid (pid_to_ptid (ret
));
1304 /* If we didn't find a process, one of two things presumably happened:
1305 - A process we started and then detached from has exited. Ignore it.
1306 - A process we are controlling has forked and the new child's stop
1307 was reported to us by the kernel. Save its PID. */
1308 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1310 add_to_pid_list (&stopped_pids
, ret
, *wstatp
);
1313 else if (child
== NULL
)
1318 child
->last_status
= *wstatp
;
1320 if (WIFSTOPPED (*wstatp
))
1322 struct process_info
*proc
;
1324 /* Architecture-specific setup after inferior is running. This
1325 needs to happen after we have attached to the inferior and it
1326 is stopped for the first time, but before we access any
1327 inferior registers. */
1328 proc
= find_process_pid (pid_of (child
));
1329 if (proc
->private->new_inferior
)
1331 struct thread_info
*saved_inferior
;
1333 saved_inferior
= current_inferior
;
1334 current_inferior
= get_lwp_thread (child
);
1336 the_low_target
.arch_setup ();
1338 current_inferior
= saved_inferior
;
1340 proc
->private->new_inferior
= 0;
1344 /* Fetch the possibly triggered data watchpoint info and store it in
1347 On some archs, like x86, that use debug registers to set
1348 watchpoints, it's possible that the way to know which watched
1349 address trapped, is to check the register that is used to select
1350 which address to watch. Problem is, between setting the
1351 watchpoint and reading back which data address trapped, the user
1352 may change the set of watchpoints, and, as a consequence, GDB
1353 changes the debug registers in the inferior. To avoid reading
1354 back a stale stopped-data-address when that happens, we cache in
1355 LP the fact that a watchpoint trapped, and the corresponding data
1356 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1357 changes the debug registers meanwhile, we have the cached data we
1360 if (WIFSTOPPED (*wstatp
) && WSTOPSIG (*wstatp
) == SIGTRAP
)
1362 if (the_low_target
.stopped_by_watchpoint
== NULL
)
1364 child
->stopped_by_watchpoint
= 0;
1368 struct thread_info
*saved_inferior
;
1370 saved_inferior
= current_inferior
;
1371 current_inferior
= get_lwp_thread (child
);
1373 child
->stopped_by_watchpoint
1374 = the_low_target
.stopped_by_watchpoint ();
1376 if (child
->stopped_by_watchpoint
)
1378 if (the_low_target
.stopped_data_address
!= NULL
)
1379 child
->stopped_data_address
1380 = the_low_target
.stopped_data_address ();
1382 child
->stopped_data_address
= 0;
1385 current_inferior
= saved_inferior
;
1389 /* Store the STOP_PC, with adjustment applied. This depends on the
1390 architecture being defined already (so that CHILD has a valid
1391 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1393 if (WIFSTOPPED (*wstatp
))
1394 child
->stop_pc
= get_stop_pc (child
);
1397 && WIFSTOPPED (*wstatp
)
1398 && the_low_target
.get_pc
!= NULL
)
1400 struct thread_info
*saved_inferior
= current_inferior
;
1401 struct regcache
*regcache
;
1404 current_inferior
= get_lwp_thread (child
);
1405 regcache
= get_thread_regcache (current_inferior
, 1);
1406 pc
= (*the_low_target
.get_pc
) (regcache
);
1407 fprintf (stderr
, "linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1408 current_inferior
= saved_inferior
;
1414 /* This function should only be called if the LWP got a SIGTRAP.
1416 Handle any tracepoint steps or hits. Return true if a tracepoint
1417 event was handled, 0 otherwise. */
1420 handle_tracepoints (struct lwp_info
*lwp
)
1422 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1423 int tpoint_related_event
= 0;
1425 /* If this tracepoint hit causes a tracing stop, we'll immediately
1426 uninsert tracepoints. To do this, we temporarily pause all
1427 threads, unpatch away, and then unpause threads. We need to make
1428 sure the unpausing doesn't resume LWP too. */
1431 /* And we need to be sure that any all-threads-stopping doesn't try
1432 to move threads out of the jump pads, as it could deadlock the
1433 inferior (LWP could be in the jump pad, maybe even holding the
1436 /* Do any necessary step collect actions. */
1437 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1439 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1441 /* See if we just hit a tracepoint and do its main collect
1443 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1447 gdb_assert (lwp
->suspended
== 0);
1448 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1450 if (tpoint_related_event
)
1453 fprintf (stderr
, "got a tracepoint event\n");
1460 /* Convenience wrapper. Returns true if LWP is presently collecting a
1464 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1465 struct fast_tpoint_collect_status
*status
)
1467 CORE_ADDR thread_area
;
1469 if (the_low_target
.get_thread_area
== NULL
)
1472 /* Get the thread area address. This is used to recognize which
1473 thread is which when tracing with the in-process agent library.
1474 We don't read anything from the address, and treat it as opaque;
1475 it's the address itself that we assume is unique per-thread. */
1476 if ((*the_low_target
.get_thread_area
) (lwpid_of (lwp
), &thread_area
) == -1)
1479 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1482 /* The reason we resume in the caller, is because we want to be able
1483 to pass lwp->status_pending as WSTAT, and we need to clear
1484 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1485 refuses to resume. */
1488 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1490 struct thread_info
*saved_inferior
;
1492 saved_inferior
= current_inferior
;
1493 current_inferior
= get_lwp_thread (lwp
);
1496 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1497 && supports_fast_tracepoints ()
1498 && agent_loaded_p ())
1500 struct fast_tpoint_collect_status status
;
1505 Checking whether LWP %ld needs to move out of the jump pad.\n",
1508 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1511 || (WSTOPSIG (*wstat
) != SIGILL
1512 && WSTOPSIG (*wstat
) != SIGFPE
1513 && WSTOPSIG (*wstat
) != SIGSEGV
1514 && WSTOPSIG (*wstat
) != SIGBUS
))
1516 lwp
->collecting_fast_tracepoint
= r
;
1520 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1522 /* Haven't executed the original instruction yet.
1523 Set breakpoint there, and wait till it's hit,
1524 then single-step until exiting the jump pad. */
1525 lwp
->exit_jump_pad_bkpt
1526 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1531 Checking whether LWP %ld needs to move out of the jump pad...it does\n",
1533 current_inferior
= saved_inferior
;
1540 /* If we get a synchronous signal while collecting, *and*
1541 while executing the (relocated) original instruction,
1542 reset the PC to point at the tpoint address, before
1543 reporting to GDB. Otherwise, it's an IPA lib bug: just
1544 report the signal to GDB, and pray for the best. */
1546 lwp
->collecting_fast_tracepoint
= 0;
1549 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1550 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1553 struct regcache
*regcache
;
1555 /* The si_addr on a few signals references the address
1556 of the faulting instruction. Adjust that as
1558 if ((WSTOPSIG (*wstat
) == SIGILL
1559 || WSTOPSIG (*wstat
) == SIGFPE
1560 || WSTOPSIG (*wstat
) == SIGBUS
1561 || WSTOPSIG (*wstat
) == SIGSEGV
)
1562 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
),
1563 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
1564 /* Final check just to make sure we don't clobber
1565 the siginfo of non-kernel-sent signals. */
1566 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1568 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1569 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
),
1570 (PTRACE_TYPE_ARG3
) 0, &info
);
1573 regcache
= get_thread_regcache (get_lwp_thread (lwp
), 1);
1574 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1575 lwp
->stop_pc
= status
.tpoint_addr
;
1577 /* Cancel any fast tracepoint lock this thread was
1579 force_unlock_trace_buffer ();
1582 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1586 "Cancelling fast exit-jump-pad: removing bkpt. "
1587 "stopping all threads momentarily.\n");
1589 stop_all_lwps (1, lwp
);
1590 cancel_breakpoints ();
1592 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1593 lwp
->exit_jump_pad_bkpt
= NULL
;
1595 unstop_all_lwps (1, lwp
);
1597 gdb_assert (lwp
->suspended
>= 0);
1604 Checking whether LWP %ld needs to move out of the jump pad...no\n",
1607 current_inferior
= saved_inferior
;
1611 /* Enqueue one signal in the "signals to report later when out of the
1615 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1617 struct pending_signals
*p_sig
;
1621 Deferring signal %d for LWP %ld.\n", WSTOPSIG (*wstat
), lwpid_of (lwp
));
1625 struct pending_signals
*sig
;
1627 for (sig
= lwp
->pending_signals_to_report
;
1631 " Already queued %d\n",
1634 fprintf (stderr
, " (no more currently queued signals)\n");
1637 /* Don't enqueue non-RT signals if they are already in the deferred
1638 queue. (SIGSTOP being the easiest signal to see ending up here
1640 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1642 struct pending_signals
*sig
;
1644 for (sig
= lwp
->pending_signals_to_report
;
1648 if (sig
->signal
== WSTOPSIG (*wstat
))
1652 "Not requeuing already queued non-RT signal %d"
1661 p_sig
= xmalloc (sizeof (*p_sig
));
1662 p_sig
->prev
= lwp
->pending_signals_to_report
;
1663 p_sig
->signal
= WSTOPSIG (*wstat
);
1664 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1665 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
1668 lwp
->pending_signals_to_report
= p_sig
;
1671 /* Dequeue one signal from the "signals to report later when out of
1672 the jump pad" list. */
1675 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1677 if (lwp
->pending_signals_to_report
!= NULL
)
1679 struct pending_signals
**p_sig
;
1681 p_sig
= &lwp
->pending_signals_to_report
;
1682 while ((*p_sig
)->prev
!= NULL
)
1683 p_sig
= &(*p_sig
)->prev
;
1685 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1686 if ((*p_sig
)->info
.si_signo
!= 0)
1687 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
1693 fprintf (stderr
, "Reporting deferred signal %d for LWP %ld.\n",
1694 WSTOPSIG (*wstat
), lwpid_of (lwp
));
1698 struct pending_signals
*sig
;
1700 for (sig
= lwp
->pending_signals_to_report
;
1704 " Still queued %d\n",
1707 fprintf (stderr
, " (no more queued signals)\n");
1716 /* Arrange for a breakpoint to be hit again later. We don't keep the
1717 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1718 will handle the current event, eventually we will resume this LWP,
1719 and this breakpoint will trap again. */
1722 cancel_breakpoint (struct lwp_info
*lwp
)
1724 struct thread_info
*saved_inferior
;
1726 /* There's nothing to do if we don't support breakpoints. */
1727 if (!supports_breakpoints ())
1730 /* breakpoint_at reads from current inferior. */
1731 saved_inferior
= current_inferior
;
1732 current_inferior
= get_lwp_thread (lwp
);
1734 if ((*the_low_target
.breakpoint_at
) (lwp
->stop_pc
))
1738 "CB: Push back breakpoint for %s\n",
1739 target_pid_to_str (ptid_of (lwp
)));
1741 /* Back up the PC if necessary. */
1742 if (the_low_target
.decr_pc_after_break
)
1744 struct regcache
*regcache
1745 = get_thread_regcache (current_inferior
, 1);
1746 (*the_low_target
.set_pc
) (regcache
, lwp
->stop_pc
);
1749 current_inferior
= saved_inferior
;
1756 "CB: No breakpoint found at %s for [%s]\n",
1757 paddress (lwp
->stop_pc
),
1758 target_pid_to_str (ptid_of (lwp
)));
1761 current_inferior
= saved_inferior
;
1765 /* When the event-loop is doing a step-over, this points at the thread
1767 ptid_t step_over_bkpt
;
1769 /* Wait for an event from child PID. If PID is -1, wait for any
1770 child. Store the stop status through the status pointer WSTAT.
1771 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1772 event was found and OPTIONS contains WNOHANG. Return the PID of
1773 the stopped child otherwise. */
1776 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1778 struct lwp_info
*event_child
, *requested_child
;
1782 requested_child
= NULL
;
1784 /* Check for a lwp with a pending status. */
1786 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
1788 event_child
= (struct lwp_info
*)
1789 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1790 if (debug_threads
&& event_child
)
1791 fprintf (stderr
, "Got a pending child %ld\n", lwpid_of (event_child
));
1795 requested_child
= find_lwp_pid (ptid
);
1797 if (stopping_threads
== NOT_STOPPING_THREADS
1798 && requested_child
->status_pending_p
1799 && requested_child
->collecting_fast_tracepoint
)
1801 enqueue_one_deferred_signal (requested_child
,
1802 &requested_child
->status_pending
);
1803 requested_child
->status_pending_p
= 0;
1804 requested_child
->status_pending
= 0;
1805 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
1808 if (requested_child
->suspended
1809 && requested_child
->status_pending_p
)
1810 fatal ("requesting an event out of a suspended child?");
1812 if (requested_child
->status_pending_p
)
1813 event_child
= requested_child
;
1816 if (event_child
!= NULL
)
1819 fprintf (stderr
, "Got an event from pending child %ld (%04x)\n",
1820 lwpid_of (event_child
), event_child
->status_pending
);
1821 *wstat
= event_child
->status_pending
;
1822 event_child
->status_pending_p
= 0;
1823 event_child
->status_pending
= 0;
1824 current_inferior
= get_lwp_thread (event_child
);
1825 return lwpid_of (event_child
);
1828 if (ptid_is_pid (ptid
))
1830 /* A request to wait for a specific tgid. This is not possible
1831 with waitpid, so instead, we wait for any child, and leave
1832 children we're not interested in right now with a pending
1833 status to report later. */
1834 wait_ptid
= minus_one_ptid
;
1839 /* We only enter this loop if no process has a pending wait status. Thus
1840 any action taken in response to a wait status inside this loop is
1841 responding as soon as we detect the status, not after any pending
1845 event_child
= linux_wait_for_lwp (wait_ptid
, wstat
, options
);
1847 if ((options
& WNOHANG
) && event_child
== NULL
)
1850 fprintf (stderr
, "WNOHANG set, no event found\n");
1854 if (event_child
== NULL
)
1855 error ("event from unknown child");
1857 if (ptid_is_pid (ptid
)
1858 && ptid_get_pid (ptid
) != ptid_get_pid (ptid_of (event_child
)))
1860 if (! WIFSTOPPED (*wstat
))
1861 mark_lwp_dead (event_child
, *wstat
);
1864 event_child
->status_pending_p
= 1;
1865 event_child
->status_pending
= *wstat
;
1870 current_inferior
= get_lwp_thread (event_child
);
1872 /* Check for thread exit. */
1873 if (! WIFSTOPPED (*wstat
))
1876 fprintf (stderr
, "LWP %ld exiting\n", lwpid_of (event_child
));
1878 /* If the last thread is exiting, just return. */
1879 if (last_thread_of_process_p (current_inferior
))
1882 fprintf (stderr
, "LWP %ld is last lwp of process\n",
1883 lwpid_of (event_child
));
1884 return lwpid_of (event_child
);
1889 current_inferior
= (struct thread_info
*) all_threads
.head
;
1891 fprintf (stderr
, "Current inferior is now %ld\n",
1892 lwpid_of (get_thread_lwp (current_inferior
)));
1896 current_inferior
= NULL
;
1898 fprintf (stderr
, "Current inferior is now <NULL>\n");
1901 /* If we were waiting for this particular child to do something...
1902 well, it did something. */
1903 if (requested_child
!= NULL
)
1905 int lwpid
= lwpid_of (event_child
);
1907 /* Cancel the step-over operation --- the thread that
1908 started it is gone. */
1909 if (finish_step_over (event_child
))
1910 unstop_all_lwps (1, event_child
);
1911 delete_lwp (event_child
);
1915 delete_lwp (event_child
);
1917 /* Wait for a more interesting event. */
1921 if (event_child
->must_set_ptrace_flags
)
1923 linux_enable_event_reporting (lwpid_of (event_child
));
1924 event_child
->must_set_ptrace_flags
= 0;
1927 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1928 && *wstat
>> 16 != 0)
1930 handle_extended_wait (event_child
, *wstat
);
1934 if (WIFSTOPPED (*wstat
)
1935 && WSTOPSIG (*wstat
) == SIGSTOP
1936 && event_child
->stop_expected
)
1941 fprintf (stderr
, "Expected stop.\n");
1942 event_child
->stop_expected
= 0;
1944 should_stop
= (current_inferior
->last_resume_kind
== resume_stop
1945 || stopping_threads
!= NOT_STOPPING_THREADS
);
1949 linux_resume_one_lwp (event_child
,
1950 event_child
->stepping
, 0, NULL
);
1955 return lwpid_of (event_child
);
1962 /* Count the LWP's that have had events. */
1965 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
1967 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1968 struct thread_info
*thread
= get_lwp_thread (lp
);
1971 gdb_assert (count
!= NULL
);
1973 /* Count only resumed LWPs that have a SIGTRAP event pending that
1974 should be reported to GDB. */
1975 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1976 && thread
->last_resume_kind
!= resume_stop
1977 && lp
->status_pending_p
1978 && WIFSTOPPED (lp
->status_pending
)
1979 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1980 && !breakpoint_inserted_here (lp
->stop_pc
))
1986 /* Select the LWP (if any) that is currently being single-stepped. */
1989 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1991 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1992 struct thread_info
*thread
= get_lwp_thread (lp
);
1994 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1995 && thread
->last_resume_kind
== resume_step
1996 && lp
->status_pending_p
)
2002 /* Select the Nth LWP that has had a SIGTRAP event that should be
2006 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2008 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2009 struct thread_info
*thread
= get_lwp_thread (lp
);
2010 int *selector
= data
;
2012 gdb_assert (selector
!= NULL
);
2014 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2015 if (thread
->last_resume_kind
!= resume_stop
2016 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2017 && lp
->status_pending_p
2018 && WIFSTOPPED (lp
->status_pending
)
2019 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2020 && !breakpoint_inserted_here (lp
->stop_pc
))
2021 if ((*selector
)-- == 0)
2028 cancel_breakpoints_callback (struct inferior_list_entry
*entry
, void *data
)
2030 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2031 struct thread_info
*thread
= get_lwp_thread (lp
);
2032 struct lwp_info
*event_lp
= data
;
2034 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
2038 /* If a LWP other than the LWP that we're reporting an event for has
2039 hit a GDB breakpoint (as opposed to some random trap signal),
2040 then just arrange for it to hit it again later. We don't keep
2041 the SIGTRAP status and don't forward the SIGTRAP signal to the
2042 LWP. We will handle the current event, eventually we will resume
2043 all LWPs, and this one will get its breakpoint trap again.
2045 If we do not do this, then we run the risk that the user will
2046 delete or disable the breakpoint, but the LWP will have already
2049 if (thread
->last_resume_kind
!= resume_stop
2050 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2051 && lp
->status_pending_p
2052 && WIFSTOPPED (lp
->status_pending
)
2053 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2055 && !lp
->stopped_by_watchpoint
2056 && cancel_breakpoint (lp
))
2057 /* Throw away the SIGTRAP. */
2058 lp
->status_pending_p
= 0;
2064 linux_cancel_breakpoints (void)
2066 find_inferior (&all_lwps
, cancel_breakpoints_callback
, NULL
);
2069 /* Select one LWP out of those that have events pending. */
2072 select_event_lwp (struct lwp_info
**orig_lp
)
2075 int random_selector
;
2076 struct lwp_info
*event_lp
;
2078 /* Give preference to any LWP that is being single-stepped. */
2080 = (struct lwp_info
*) find_inferior (&all_lwps
,
2081 select_singlestep_lwp_callback
, NULL
);
2082 if (event_lp
!= NULL
)
2086 "SEL: Select single-step %s\n",
2087 target_pid_to_str (ptid_of (event_lp
)));
2091 /* No single-stepping LWP. Select one at random, out of those
2092 which have had SIGTRAP events. */
2094 /* First see how many SIGTRAP events we have. */
2095 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
2097 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
2098 random_selector
= (int)
2099 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2101 if (debug_threads
&& num_events
> 1)
2103 "SEL: Found %d SIGTRAP events, selecting #%d\n",
2104 num_events
, random_selector
);
2106 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
2107 select_event_lwp_callback
,
2111 if (event_lp
!= NULL
)
2113 /* Switch the event LWP. */
2114 *orig_lp
= event_lp
;
2118 /* Decrement the suspend count of an LWP. */
2121 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2123 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2125 /* Ignore EXCEPT. */
2131 gdb_assert (lwp
->suspended
>= 0);
2135 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2139 unsuspend_all_lwps (struct lwp_info
*except
)
2141 find_inferior (&all_lwps
, unsuspend_one_lwp
, except
);
2144 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2145 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2147 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2148 static ptid_t
linux_wait_1 (ptid_t ptid
,
2149 struct target_waitstatus
*ourstatus
,
2150 int target_options
);
2152 /* Stabilize threads (move out of jump pads).
2154 If a thread is midway collecting a fast tracepoint, we need to
2155 finish the collection and move it out of the jump pad before
2156 reporting the signal.
2158 This avoids recursion while collecting (when a signal arrives
2159 midway, and the signal handler itself collects), which would trash
2160 the trace buffer. In case the user set a breakpoint in a signal
2161 handler, this avoids the backtrace showing the jump pad, etc..
2162 Most importantly, there are certain things we can't do safely if
2163 threads are stopped in a jump pad (or in its callee's). For
2166 - starting a new trace run. A thread still collecting the
2167 previous run, could trash the trace buffer when resumed. The trace
2168 buffer control structures would have been reset but the thread had
2169 no way to tell. The thread could even midway memcpy'ing to the
2170 buffer, which would mean that when resumed, it would clobber the
2171 trace buffer that had been set for a new run.
2173 - we can't rewrite/reuse the jump pads for new tracepoints
2174 safely. Say you do tstart while a thread is stopped midway while
2175 collecting. When the thread is later resumed, it finishes the
2176 collection, and returns to the jump pad, to execute the original
2177 instruction that was under the tracepoint jump at the time the
2178 older run had been started. If the jump pad had been rewritten
2179 since for something else in the new run, the thread would now
2180 execute the wrong / random instructions. */
2183 linux_stabilize_threads (void)
2185 struct thread_info
*save_inferior
;
2186 struct lwp_info
*lwp_stuck
;
2189 = (struct lwp_info
*) find_inferior (&all_lwps
,
2190 stuck_in_jump_pad_callback
, NULL
);
2191 if (lwp_stuck
!= NULL
)
2194 fprintf (stderr
, "can't stabilize, LWP %ld is stuck in jump pad\n",
2195 lwpid_of (lwp_stuck
));
2199 save_inferior
= current_inferior
;
2201 stabilizing_threads
= 1;
2204 for_each_inferior (&all_lwps
, move_out_of_jump_pad_callback
);
2206 /* Loop until all are stopped out of the jump pads. */
2207 while (find_inferior (&all_lwps
, lwp_running
, NULL
) != NULL
)
2209 struct target_waitstatus ourstatus
;
2210 struct lwp_info
*lwp
;
2213 /* Note that we go through the full wait even loop. While
2214 moving threads out of jump pad, we need to be able to step
2215 over internal breakpoints and such. */
2216 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2218 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2220 lwp
= get_thread_lwp (current_inferior
);
2225 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2226 || current_inferior
->last_resume_kind
== resume_stop
)
2228 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2229 enqueue_one_deferred_signal (lwp
, &wstat
);
2234 find_inferior (&all_lwps
, unsuspend_one_lwp
, NULL
);
2236 stabilizing_threads
= 0;
2238 current_inferior
= save_inferior
;
2243 = (struct lwp_info
*) find_inferior (&all_lwps
,
2244 stuck_in_jump_pad_callback
, NULL
);
2245 if (lwp_stuck
!= NULL
)
2246 fprintf (stderr
, "couldn't stabilize, LWP %ld got stuck in jump pad\n",
2247 lwpid_of (lwp_stuck
));
2251 /* Wait for process, returns status. */
2254 linux_wait_1 (ptid_t ptid
,
2255 struct target_waitstatus
*ourstatus
, int target_options
)
2258 struct lwp_info
*event_child
;
2261 int step_over_finished
;
2262 int bp_explains_trap
;
2263 int maybe_internal_trap
;
2268 /* Translate generic target options into linux options. */
2270 if (target_options
& TARGET_WNOHANG
)
2274 bp_explains_trap
= 0;
2277 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2279 /* If we were only supposed to resume one thread, only wait for
2280 that thread - if it's still alive. If it died, however - which
2281 can happen if we're coming from the thread death case below -
2282 then we need to make sure we restart the other threads. We could
2283 pick a thread at random or restart all; restarting all is less
2286 && !ptid_equal (cont_thread
, null_ptid
)
2287 && !ptid_equal (cont_thread
, minus_one_ptid
))
2289 struct thread_info
*thread
;
2291 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
2294 /* No stepping, no signal - unless one is pending already, of course. */
2297 struct thread_resume resume_info
;
2298 resume_info
.thread
= minus_one_ptid
;
2299 resume_info
.kind
= resume_continue
;
2300 resume_info
.sig
= 0;
2301 linux_resume (&resume_info
, 1);
2307 if (ptid_equal (step_over_bkpt
, null_ptid
))
2308 pid
= linux_wait_for_event (ptid
, &w
, options
);
2312 fprintf (stderr
, "step_over_bkpt set [%s], doing a blocking wait\n",
2313 target_pid_to_str (step_over_bkpt
));
2314 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2317 if (pid
== 0) /* only if TARGET_WNOHANG */
2320 event_child
= get_thread_lwp (current_inferior
);
2322 /* If we are waiting for a particular child, and it exited,
2323 linux_wait_for_event will return its exit status. Similarly if
2324 the last child exited. If this is not the last child, however,
2325 do not report it as exited until there is a 'thread exited' response
2326 available in the remote protocol. Instead, just wait for another event.
2327 This should be safe, because if the thread crashed we will already
2328 have reported the termination signal to GDB; that should stop any
2329 in-progress stepping operations, etc.
2331 Report the exit status of the last thread to exit. This matches
2332 LinuxThreads' behavior. */
2334 if (last_thread_of_process_p (current_inferior
))
2336 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2340 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2341 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2345 "\nChild exited with retcode = %x \n",
2350 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2351 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
2355 "\nChild terminated with signal = %x \n",
2360 return ptid_of (event_child
);
2365 if (!WIFSTOPPED (w
))
2369 /* If this event was not handled before, and is not a SIGTRAP, we
2370 report it. SIGILL and SIGSEGV are also treated as traps in case
2371 a breakpoint is inserted at the current PC. If this target does
2372 not support internal breakpoints at all, we also report the
2373 SIGTRAP without further processing; it's of no concern to us. */
2375 = (supports_breakpoints ()
2376 && (WSTOPSIG (w
) == SIGTRAP
2377 || ((WSTOPSIG (w
) == SIGILL
2378 || WSTOPSIG (w
) == SIGSEGV
)
2379 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2381 if (maybe_internal_trap
)
2383 /* Handle anything that requires bookkeeping before deciding to
2384 report the event or continue waiting. */
2386 /* First check if we can explain the SIGTRAP with an internal
2387 breakpoint, or if we should possibly report the event to GDB.
2388 Do this before anything that may remove or insert a
2390 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2392 /* We have a SIGTRAP, possibly a step-over dance has just
2393 finished. If so, tweak the state machine accordingly,
2394 reinsert breakpoints and delete any reinsert (software
2395 single-step) breakpoints. */
2396 step_over_finished
= finish_step_over (event_child
);
2398 /* Now invoke the callbacks of any internal breakpoints there. */
2399 check_breakpoints (event_child
->stop_pc
);
2401 /* Handle tracepoint data collecting. This may overflow the
2402 trace buffer, and cause a tracing stop, removing
2404 trace_event
= handle_tracepoints (event_child
);
2406 if (bp_explains_trap
)
2408 /* If we stepped or ran into an internal breakpoint, we've
2409 already handled it. So next time we resume (from this
2410 PC), we should step over it. */
2412 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2414 if (breakpoint_here (event_child
->stop_pc
))
2415 event_child
->need_step_over
= 1;
2420 /* We have some other signal, possibly a step-over dance was in
2421 progress, and it should be cancelled too. */
2422 step_over_finished
= finish_step_over (event_child
);
2425 /* We have all the data we need. Either report the event to GDB, or
2426 resume threads and keep waiting for more. */
2428 /* If we're collecting a fast tracepoint, finish the collection and
2429 move out of the jump pad before delivering a signal. See
2430 linux_stabilize_threads. */
2433 && WSTOPSIG (w
) != SIGTRAP
2434 && supports_fast_tracepoints ()
2435 && agent_loaded_p ())
2439 "Got signal %d for LWP %ld. Check if we need "
2440 "to defer or adjust it.\n",
2441 WSTOPSIG (w
), lwpid_of (event_child
));
2443 /* Allow debugging the jump pad itself. */
2444 if (current_inferior
->last_resume_kind
!= resume_step
2445 && maybe_move_out_of_jump_pad (event_child
, &w
))
2447 enqueue_one_deferred_signal (event_child
, &w
);
2451 "Signal %d for LWP %ld deferred (in jump pad)\n",
2452 WSTOPSIG (w
), lwpid_of (event_child
));
2454 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2459 if (event_child
->collecting_fast_tracepoint
)
2463 LWP %ld was trying to move out of the jump pad (%d). \
2464 Check if we're already there.\n",
2465 lwpid_of (event_child
),
2466 event_child
->collecting_fast_tracepoint
);
2470 event_child
->collecting_fast_tracepoint
2471 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2473 if (event_child
->collecting_fast_tracepoint
!= 1)
2475 /* No longer need this breakpoint. */
2476 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2480 "No longer need exit-jump-pad bkpt; removing it."
2481 "stopping all threads momentarily.\n");
2483 /* Other running threads could hit this breakpoint.
2484 We don't handle moribund locations like GDB does,
2485 instead we always pause all threads when removing
2486 breakpoints, so that any step-over or
2487 decr_pc_after_break adjustment is always taken
2488 care of while the breakpoint is still
2490 stop_all_lwps (1, event_child
);
2491 cancel_breakpoints ();
2493 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2494 event_child
->exit_jump_pad_bkpt
= NULL
;
2496 unstop_all_lwps (1, event_child
);
2498 gdb_assert (event_child
->suspended
>= 0);
2502 if (event_child
->collecting_fast_tracepoint
== 0)
2506 "fast tracepoint finished "
2507 "collecting successfully.\n");
2509 /* We may have a deferred signal to report. */
2510 if (dequeue_one_deferred_signal (event_child
, &w
))
2513 fprintf (stderr
, "dequeued one signal.\n");
2518 fprintf (stderr
, "no deferred signals.\n");
2520 if (stabilizing_threads
)
2522 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2523 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
2524 return ptid_of (event_child
);
2530 /* Check whether GDB would be interested in this event. */
2532 /* If GDB is not interested in this signal, don't stop other
2533 threads, and don't report it to GDB. Just resume the inferior
2534 right away. We do this for threading-related signals as well as
2535 any that GDB specifically requested we ignore. But never ignore
2536 SIGSTOP if we sent it ourselves, and do not ignore signals when
2537 stepping - they may require special handling to skip the signal
2539 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2542 && current_inferior
->last_resume_kind
!= resume_step
2544 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2545 (current_process ()->private->thread_db
!= NULL
2546 && (WSTOPSIG (w
) == __SIGRTMIN
2547 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2550 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
2551 && !(WSTOPSIG (w
) == SIGSTOP
2552 && current_inferior
->last_resume_kind
== resume_stop
))))
2554 siginfo_t info
, *info_p
;
2557 fprintf (stderr
, "Ignored signal %d for LWP %ld.\n",
2558 WSTOPSIG (w
), lwpid_of (event_child
));
2560 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
),
2561 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
2565 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2566 WSTOPSIG (w
), info_p
);
2570 /* Note that all addresses are always "out of the step range" when
2571 there's no range to begin with. */
2572 in_step_range
= lwp_in_step_range (event_child
);
2574 /* If GDB wanted this thread to single step, and the thread is out
2575 of the step range, we always want to report the SIGTRAP, and let
2576 GDB handle it. Watchpoints should always be reported. So should
2577 signals we can't explain. A SIGTRAP we can't explain could be a
2578 GDB breakpoint --- we may or not support Z0 breakpoints. If we
2579 do, we're be able to handle GDB breakpoints on top of internal
2580 breakpoints, by handling the internal breakpoint and still
2581 reporting the event to GDB. If we don't, we're out of luck, GDB
2582 won't see the breakpoint hit. */
2583 report_to_gdb
= (!maybe_internal_trap
2584 || (current_inferior
->last_resume_kind
== resume_step
2586 || event_child
->stopped_by_watchpoint
2587 || (!step_over_finished
&& !in_step_range
2588 && !bp_explains_trap
&& !trace_event
)
2589 || (gdb_breakpoint_here (event_child
->stop_pc
)
2590 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
2591 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
)));
2593 run_breakpoint_commands (event_child
->stop_pc
);
2595 /* We found no reason GDB would want us to stop. We either hit one
2596 of our own breakpoints, or finished an internal step GDB
2597 shouldn't know about. */
2602 if (bp_explains_trap
)
2603 fprintf (stderr
, "Hit a gdbserver breakpoint.\n");
2604 if (step_over_finished
)
2605 fprintf (stderr
, "Step-over finished.\n");
2607 fprintf (stderr
, "Tracepoint event.\n");
2608 if (lwp_in_step_range (event_child
))
2609 fprintf (stderr
, "Range stepping pc 0x%s [0x%s, 0x%s).\n",
2610 paddress (event_child
->stop_pc
),
2611 paddress (event_child
->step_range_start
),
2612 paddress (event_child
->step_range_end
));
2615 /* We're not reporting this breakpoint to GDB, so apply the
2616 decr_pc_after_break adjustment to the inferior's regcache
2619 if (the_low_target
.set_pc
!= NULL
)
2621 struct regcache
*regcache
2622 = get_thread_regcache (get_lwp_thread (event_child
), 1);
2623 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2626 /* We may have finished stepping over a breakpoint. If so,
2627 we've stopped and suspended all LWPs momentarily except the
2628 stepping one. This is where we resume them all again. We're
2629 going to keep waiting, so use proceed, which handles stepping
2630 over the next breakpoint. */
2632 fprintf (stderr
, "proceeding all threads.\n");
2634 if (step_over_finished
)
2635 unsuspend_all_lwps (event_child
);
2637 proceed_all_lwps ();
2643 if (current_inferior
->last_resume_kind
== resume_step
)
2645 if (event_child
->step_range_start
== event_child
->step_range_end
)
2646 fprintf (stderr
, "GDB wanted to single-step, reporting event.\n");
2647 else if (!lwp_in_step_range (event_child
))
2648 fprintf (stderr
, "Out of step range, reporting event.\n");
2650 if (event_child
->stopped_by_watchpoint
)
2651 fprintf (stderr
, "Stopped by watchpoint.\n");
2652 if (gdb_breakpoint_here (event_child
->stop_pc
))
2653 fprintf (stderr
, "Stopped by GDB breakpoint.\n");
2655 fprintf (stderr
, "Hit a non-gdbserver trap event.\n");
2658 /* Alright, we're going to report a stop. */
2660 if (!non_stop
&& !stabilizing_threads
)
2662 /* In all-stop, stop all threads. */
2663 stop_all_lwps (0, NULL
);
2665 /* If we're not waiting for a specific LWP, choose an event LWP
2666 from among those that have had events. Giving equal priority
2667 to all LWPs that have had events helps prevent
2669 if (ptid_equal (ptid
, minus_one_ptid
))
2671 event_child
->status_pending_p
= 1;
2672 event_child
->status_pending
= w
;
2674 select_event_lwp (&event_child
);
2676 event_child
->status_pending_p
= 0;
2677 w
= event_child
->status_pending
;
2680 /* Now that we've selected our final event LWP, cancel any
2681 breakpoints in other LWPs that have hit a GDB breakpoint.
2682 See the comment in cancel_breakpoints_callback to find out
2684 find_inferior (&all_lwps
, cancel_breakpoints_callback
, event_child
);
2686 /* If we were going a step-over, all other threads but the stepping one
2687 had been paused in start_step_over, with their suspend counts
2688 incremented. We don't want to do a full unstop/unpause, because we're
2689 in all-stop mode (so we want threads stopped), but we still need to
2690 unsuspend the other threads, to decrement their `suspended' count
2692 if (step_over_finished
)
2693 unsuspend_all_lwps (event_child
);
2695 /* Stabilize threads (move out of jump pads). */
2696 stabilize_threads ();
2700 /* If we just finished a step-over, then all threads had been
2701 momentarily paused. In all-stop, that's fine, we want
2702 threads stopped by now anyway. In non-stop, we need to
2703 re-resume threads that GDB wanted to be running. */
2704 if (step_over_finished
)
2705 unstop_all_lwps (1, event_child
);
2708 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2710 if (current_inferior
->last_resume_kind
== resume_stop
2711 && WSTOPSIG (w
) == SIGSTOP
)
2713 /* A thread that has been requested to stop by GDB with vCont;t,
2714 and it stopped cleanly, so report as SIG0. The use of
2715 SIGSTOP is an implementation detail. */
2716 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
2718 else if (current_inferior
->last_resume_kind
== resume_stop
2719 && WSTOPSIG (w
) != SIGSTOP
)
2721 /* A thread that has been requested to stop by GDB with vCont;t,
2722 but, it stopped for other reasons. */
2723 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
2727 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
2730 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
2733 fprintf (stderr
, "linux_wait ret = %s, %d, %d\n",
2734 target_pid_to_str (ptid_of (event_child
)),
2736 ourstatus
->value
.sig
);
2738 return ptid_of (event_child
);
2741 /* Get rid of any pending event in the pipe. */
2743 async_file_flush (void)
2749 ret
= read (linux_event_pipe
[0], &buf
, 1);
2750 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
2753 /* Put something in the pipe, so the event loop wakes up. */
2755 async_file_mark (void)
2759 async_file_flush ();
2762 ret
= write (linux_event_pipe
[1], "+", 1);
2763 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
2765 /* Ignore EAGAIN. If the pipe is full, the event loop will already
2766 be awakened anyway. */
2770 linux_wait (ptid_t ptid
,
2771 struct target_waitstatus
*ourstatus
, int target_options
)
2776 fprintf (stderr
, "linux_wait: [%s]\n", target_pid_to_str (ptid
));
2778 /* Flush the async file first. */
2779 if (target_is_async_p ())
2780 async_file_flush ();
2782 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
2784 /* If at least one stop was reported, there may be more. A single
2785 SIGCHLD can signal more than one child stop. */
2786 if (target_is_async_p ()
2787 && (target_options
& TARGET_WNOHANG
) != 0
2788 && !ptid_equal (event_ptid
, null_ptid
))
2794 /* Send a signal to an LWP. */
2797 kill_lwp (unsigned long lwpid
, int signo
)
2799 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2800 fails, then we are not using nptl threads and we should be using kill. */
2804 static int tkill_failed
;
2811 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2812 if (errno
!= ENOSYS
)
2819 return kill (lwpid
, signo
);
2823 linux_stop_lwp (struct lwp_info
*lwp
)
2829 send_sigstop (struct lwp_info
*lwp
)
2833 pid
= lwpid_of (lwp
);
2835 /* If we already have a pending stop signal for this process, don't
2837 if (lwp
->stop_expected
)
2840 fprintf (stderr
, "Have pending sigstop for lwp %d\n", pid
);
2846 fprintf (stderr
, "Sending sigstop to lwp %d\n", pid
);
2848 lwp
->stop_expected
= 1;
2849 kill_lwp (pid
, SIGSTOP
);
2853 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
2855 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2857 /* Ignore EXCEPT. */
2868 /* Increment the suspend count of an LWP, and stop it, if not stopped
2871 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
2874 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2876 /* Ignore EXCEPT. */
2882 return send_sigstop_callback (entry
, except
);
2886 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
2888 /* It's dead, really. */
2891 /* Store the exit status for later. */
2892 lwp
->status_pending_p
= 1;
2893 lwp
->status_pending
= wstat
;
2895 /* Prevent trying to stop it. */
2898 /* No further stops are expected from a dead lwp. */
2899 lwp
->stop_expected
= 0;
2903 wait_for_sigstop (struct inferior_list_entry
*entry
)
2905 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2906 struct thread_info
*saved_inferior
;
2915 fprintf (stderr
, "wait_for_sigstop: LWP %ld already stopped\n",
2920 saved_inferior
= current_inferior
;
2921 if (saved_inferior
!= NULL
)
2922 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
2924 saved_tid
= null_ptid
; /* avoid bogus unused warning */
2926 ptid
= lwp
->head
.id
;
2929 fprintf (stderr
, "wait_for_sigstop: pulling one event\n");
2931 pid
= linux_wait_for_event (ptid
, &wstat
, __WALL
);
2933 /* If we stopped with a non-SIGSTOP signal, save it for later
2934 and record the pending SIGSTOP. If the process exited, just
2936 if (WIFSTOPPED (wstat
))
2939 fprintf (stderr
, "LWP %ld stopped with signal %d\n",
2940 lwpid_of (lwp
), WSTOPSIG (wstat
));
2942 if (WSTOPSIG (wstat
) != SIGSTOP
)
2945 fprintf (stderr
, "LWP %ld stopped with non-sigstop status %06x\n",
2946 lwpid_of (lwp
), wstat
);
2948 lwp
->status_pending_p
= 1;
2949 lwp
->status_pending
= wstat
;
2955 fprintf (stderr
, "Process %d exited while stopping LWPs\n", pid
);
2957 lwp
= find_lwp_pid (pid_to_ptid (pid
));
2960 /* Leave this status pending for the next time we're able to
2961 report it. In the mean time, we'll report this lwp as
2962 dead to GDB, so GDB doesn't try to read registers and
2963 memory from it. This can only happen if this was the
2964 last thread of the process; otherwise, PID is removed
2965 from the thread tables before linux_wait_for_event
2967 mark_lwp_dead (lwp
, wstat
);
2971 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
2972 current_inferior
= saved_inferior
;
2976 fprintf (stderr
, "Previously current thread died.\n");
2980 /* We can't change the current inferior behind GDB's back,
2981 otherwise, a subsequent command may apply to the wrong
2983 current_inferior
= NULL
;
2987 /* Set a valid thread as current. */
2988 set_desired_inferior (0);
2993 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
2994 move it out, because we need to report the stop event to GDB. For
2995 example, if the user puts a breakpoint in the jump pad, it's
2996 because she wants to debug it. */
2999 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3001 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3002 struct thread_info
*thread
= get_lwp_thread (lwp
);
3004 gdb_assert (lwp
->suspended
== 0);
3005 gdb_assert (lwp
->stopped
);
3007 /* Allow debugging the jump pad, gdb_collect, etc.. */
3008 return (supports_fast_tracepoints ()
3009 && agent_loaded_p ()
3010 && (gdb_breakpoint_here (lwp
->stop_pc
)
3011 || lwp
->stopped_by_watchpoint
3012 || thread
->last_resume_kind
== resume_step
)
3013 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3017 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3019 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3020 struct thread_info
*thread
= get_lwp_thread (lwp
);
3023 gdb_assert (lwp
->suspended
== 0);
3024 gdb_assert (lwp
->stopped
);
3026 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3028 /* Allow debugging the jump pad, gdb_collect, etc. */
3029 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3030 && !lwp
->stopped_by_watchpoint
3031 && thread
->last_resume_kind
!= resume_step
3032 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3036 "LWP %ld needs stabilizing (in jump pad)\n",
3041 lwp
->status_pending_p
= 0;
3042 enqueue_one_deferred_signal (lwp
, wstat
);
3046 "Signal %d for LWP %ld deferred "
3048 WSTOPSIG (*wstat
), lwpid_of (lwp
));
3051 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3058 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3060 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3069 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3070 If SUSPEND, then also increase the suspend count of every LWP,
3074 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3076 /* Should not be called recursively. */
3077 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3079 stopping_threads
= (suspend
3080 ? STOPPING_AND_SUSPENDING_THREADS
3081 : STOPPING_THREADS
);
3084 find_inferior (&all_lwps
, suspend_and_send_sigstop_callback
, except
);
3086 find_inferior (&all_lwps
, send_sigstop_callback
, except
);
3087 for_each_inferior (&all_lwps
, wait_for_sigstop
);
3088 stopping_threads
= NOT_STOPPING_THREADS
;
3091 /* Resume execution of the inferior process.
3092 If STEP is nonzero, single-step it.
3093 If SIGNAL is nonzero, give it that signal. */
3096 linux_resume_one_lwp (struct lwp_info
*lwp
,
3097 int step
, int signal
, siginfo_t
*info
)
3099 struct thread_info
*saved_inferior
;
3100 int fast_tp_collecting
;
3102 if (lwp
->stopped
== 0)
3105 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3107 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3109 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3110 user used the "jump" command, or "set $pc = foo"). */
3111 if (lwp
->stop_pc
!= get_pc (lwp
))
3113 /* Collecting 'while-stepping' actions doesn't make sense
3115 release_while_stepping_state_list (get_lwp_thread (lwp
));
3118 /* If we have pending signals or status, and a new signal, enqueue the
3119 signal. Also enqueue the signal if we are waiting to reinsert a
3120 breakpoint; it will be picked up again below. */
3122 && (lwp
->status_pending_p
3123 || lwp
->pending_signals
!= NULL
3124 || lwp
->bp_reinsert
!= 0
3125 || fast_tp_collecting
))
3127 struct pending_signals
*p_sig
;
3128 p_sig
= xmalloc (sizeof (*p_sig
));
3129 p_sig
->prev
= lwp
->pending_signals
;
3130 p_sig
->signal
= signal
;
3132 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3134 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3135 lwp
->pending_signals
= p_sig
;
3138 if (lwp
->status_pending_p
)
3141 fprintf (stderr
, "Not resuming lwp %ld (%s, signal %d, stop %s);"
3142 " has pending status\n",
3143 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3144 lwp
->stop_expected
? "expected" : "not expected");
3148 saved_inferior
= current_inferior
;
3149 current_inferior
= get_lwp_thread (lwp
);
3152 fprintf (stderr
, "Resuming lwp %ld (%s, signal %d, stop %s)\n",
3153 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3154 lwp
->stop_expected
? "expected" : "not expected");
3156 /* This bit needs some thinking about. If we get a signal that
3157 we must report while a single-step reinsert is still pending,
3158 we often end up resuming the thread. It might be better to
3159 (ew) allow a stack of pending events; then we could be sure that
3160 the reinsert happened right away and not lose any signals.
3162 Making this stack would also shrink the window in which breakpoints are
3163 uninserted (see comment in linux_wait_for_lwp) but not enough for
3164 complete correctness, so it won't solve that problem. It may be
3165 worthwhile just to solve this one, however. */
3166 if (lwp
->bp_reinsert
!= 0)
3169 fprintf (stderr
, " pending reinsert at 0x%s\n",
3170 paddress (lwp
->bp_reinsert
));
3172 if (can_hardware_single_step ())
3174 if (fast_tp_collecting
== 0)
3177 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
3179 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
3186 /* Postpone any pending signal. It was enqueued above. */
3190 if (fast_tp_collecting
== 1)
3194 lwp %ld wants to get out of fast tracepoint jump pad (exit-jump-pad-bkpt)\n",
3197 /* Postpone any pending signal. It was enqueued above. */
3200 else if (fast_tp_collecting
== 2)
3204 lwp %ld wants to get out of fast tracepoint jump pad single-stepping\n",
3207 if (can_hardware_single_step ())
3210 fatal ("moving out of jump pad single-stepping"
3211 " not implemented on this target");
3213 /* Postpone any pending signal. It was enqueued above. */
3217 /* If we have while-stepping actions in this thread set it stepping.
3218 If we have a signal to deliver, it may or may not be set to
3219 SIG_IGN, we don't know. Assume so, and allow collecting
3220 while-stepping into a signal handler. A possible smart thing to
3221 do would be to set an internal breakpoint at the signal return
3222 address, continue, and carry on catching this while-stepping
3223 action only when that breakpoint is hit. A future
3225 if (get_lwp_thread (lwp
)->while_stepping
!= NULL
3226 && can_hardware_single_step ())
3230 "lwp %ld has a while-stepping action -> forcing step.\n",
3235 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
3237 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
3238 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
3239 fprintf (stderr
, " resuming from pc 0x%lx\n", (long) pc
);
3242 /* If we have pending signals, consume one unless we are trying to
3243 reinsert a breakpoint or we're trying to finish a fast tracepoint
3245 if (lwp
->pending_signals
!= NULL
3246 && lwp
->bp_reinsert
== 0
3247 && fast_tp_collecting
== 0)
3249 struct pending_signals
**p_sig
;
3251 p_sig
= &lwp
->pending_signals
;
3252 while ((*p_sig
)->prev
!= NULL
)
3253 p_sig
= &(*p_sig
)->prev
;
3255 signal
= (*p_sig
)->signal
;
3256 if ((*p_sig
)->info
.si_signo
!= 0)
3257 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
3264 if (the_low_target
.prepare_to_resume
!= NULL
)
3265 the_low_target
.prepare_to_resume (lwp
);
3267 regcache_invalidate_thread (get_lwp_thread (lwp
));
3270 lwp
->stopped_by_watchpoint
= 0;
3271 lwp
->stepping
= step
;
3272 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
),
3273 (PTRACE_TYPE_ARG3
) 0,
3274 /* Coerce to a uintptr_t first to avoid potential gcc warning
3275 of coercing an 8 byte integer to a 4 byte pointer. */
3276 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
3278 current_inferior
= saved_inferior
;
3281 /* ESRCH from ptrace either means that the thread was already
3282 running (an error) or that it is gone (a race condition). If
3283 it's gone, we will get a notification the next time we wait,
3284 so we can ignore the error. We could differentiate these
3285 two, but it's tricky without waiting; the thread still exists
3286 as a zombie, so sending it signal 0 would succeed. So just
3291 perror_with_name ("ptrace");
3295 struct thread_resume_array
3297 struct thread_resume
*resume
;
3301 /* This function is called once per thread via find_inferior.
3302 ARG is a pointer to a thread_resume_array struct.
3303 We look up the thread specified by ENTRY in ARG, and mark the thread
3304 with a pointer to the appropriate resume request.
3306 This algorithm is O(threads * resume elements), but resume elements
3307 is small (and will remain small at least until GDB supports thread
3311 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3313 struct lwp_info
*lwp
;
3314 struct thread_info
*thread
;
3316 struct thread_resume_array
*r
;
3318 thread
= (struct thread_info
*) entry
;
3319 lwp
= get_thread_lwp (thread
);
3322 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3324 ptid_t ptid
= r
->resume
[ndx
].thread
;
3325 if (ptid_equal (ptid
, minus_one_ptid
)
3326 || ptid_equal (ptid
, entry
->id
)
3327 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
3329 || (ptid_get_pid (ptid
) == pid_of (lwp
)
3330 && (ptid_is_pid (ptid
)
3331 || ptid_get_lwp (ptid
) == -1)))
3333 if (r
->resume
[ndx
].kind
== resume_stop
3334 && thread
->last_resume_kind
== resume_stop
)
3337 fprintf (stderr
, "already %s LWP %ld at GDB's request\n",
3338 thread
->last_status
.kind
== TARGET_WAITKIND_STOPPED
3346 lwp
->resume
= &r
->resume
[ndx
];
3347 thread
->last_resume_kind
= lwp
->resume
->kind
;
3349 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
3350 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
3352 /* If we had a deferred signal to report, dequeue one now.
3353 This can happen if LWP gets more than one signal while
3354 trying to get out of a jump pad. */
3356 && !lwp
->status_pending_p
3357 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3359 lwp
->status_pending_p
= 1;
3363 "Dequeueing deferred signal %d for LWP %ld, "
3364 "leaving status pending.\n",
3365 WSTOPSIG (lwp
->status_pending
), lwpid_of (lwp
));
3372 /* No resume action for this thread. */
3378 /* find_inferior callback for linux_resume.
3379 Set *FLAG_P if this lwp has an interesting status pending. */
3382 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3384 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3386 /* LWPs which will not be resumed are not interesting, because
3387 we might not wait for them next time through linux_wait. */
3388 if (lwp
->resume
== NULL
)
3391 if (lwp
->status_pending_p
)
3392 * (int *) flag_p
= 1;
3397 /* Return 1 if this lwp that GDB wants running is stopped at an
3398 internal breakpoint that we need to step over. It assumes that any
3399 required STOP_PC adjustment has already been propagated to the
3400 inferior's regcache. */
3403 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3405 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3406 struct thread_info
*thread
;
3407 struct thread_info
*saved_inferior
;
3410 /* LWPs which will not be resumed are not interesting, because we
3411 might not wait for them next time through linux_wait. */
3417 "Need step over [LWP %ld]? Ignoring, not stopped\n",
3422 thread
= get_lwp_thread (lwp
);
3424 if (thread
->last_resume_kind
== resume_stop
)
3428 "Need step over [LWP %ld]? Ignoring, should remain stopped\n",
3433 gdb_assert (lwp
->suspended
>= 0);
3439 "Need step over [LWP %ld]? Ignoring, suspended\n",
3444 if (!lwp
->need_step_over
)
3448 "Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
3451 if (lwp
->status_pending_p
)
3455 "Need step over [LWP %ld]? Ignoring, has pending status.\n",
3460 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3464 /* If the PC has changed since we stopped, then don't do anything,
3465 and let the breakpoint/tracepoint be hit. This happens if, for
3466 instance, GDB handled the decr_pc_after_break subtraction itself,
3467 GDB is OOL stepping this thread, or the user has issued a "jump"
3468 command, or poked thread's registers herself. */
3469 if (pc
!= lwp
->stop_pc
)
3473 "Need step over [LWP %ld]? Cancelling, PC was changed. "
3474 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3475 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
3477 lwp
->need_step_over
= 0;
3481 saved_inferior
= current_inferior
;
3482 current_inferior
= thread
;
3484 /* We can only step over breakpoints we know about. */
3485 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3487 /* Don't step over a breakpoint that GDB expects to hit
3488 though. If the condition is being evaluated on the target's side
3489 and it evaluate to false, step over this breakpoint as well. */
3490 if (gdb_breakpoint_here (pc
)
3491 && gdb_condition_true_at_breakpoint (pc
)
3492 && gdb_no_commands_at_breakpoint (pc
))
3496 "Need step over [LWP %ld]? yes, but found"
3497 " GDB breakpoint at 0x%s; skipping step over\n",
3498 lwpid_of (lwp
), paddress (pc
));
3500 current_inferior
= saved_inferior
;
3507 "Need step over [LWP %ld]? yes, "
3508 "found breakpoint at 0x%s\n",
3509 lwpid_of (lwp
), paddress (pc
));
3511 /* We've found an lwp that needs stepping over --- return 1 so
3512 that find_inferior stops looking. */
3513 current_inferior
= saved_inferior
;
3515 /* If the step over is cancelled, this is set again. */
3516 lwp
->need_step_over
= 0;
3521 current_inferior
= saved_inferior
;
3525 "Need step over [LWP %ld]? No, no breakpoint found at 0x%s\n",
3526 lwpid_of (lwp
), paddress (pc
));
3531 /* Start a step-over operation on LWP. When LWP stopped at a
3532 breakpoint, to make progress, we need to remove the breakpoint out
3533 of the way. If we let other threads run while we do that, they may
3534 pass by the breakpoint location and miss hitting it. To avoid
3535 that, a step-over momentarily stops all threads while LWP is
3536 single-stepped while the breakpoint is temporarily uninserted from
3537 the inferior. When the single-step finishes, we reinsert the
3538 breakpoint, and let all threads that are supposed to be running,
3541 On targets that don't support hardware single-step, we don't
3542 currently support full software single-stepping. Instead, we only
3543 support stepping over the thread event breakpoint, by asking the
3544 low target where to place a reinsert breakpoint. Since this
3545 routine assumes the breakpoint being stepped over is a thread event
3546 breakpoint, it usually assumes the return address of the current
3547 function is a good enough place to set the reinsert breakpoint. */
3550 start_step_over (struct lwp_info
*lwp
)
3552 struct thread_info
*saved_inferior
;
3558 "Starting step-over on LWP %ld. Stopping all threads\n",
3561 stop_all_lwps (1, lwp
);
3562 gdb_assert (lwp
->suspended
== 0);
3565 fprintf (stderr
, "Done stopping all threads for step-over.\n");
3567 /* Note, we should always reach here with an already adjusted PC,
3568 either by GDB (if we're resuming due to GDB's request), or by our
3569 caller, if we just finished handling an internal breakpoint GDB
3570 shouldn't care about. */
3573 saved_inferior
= current_inferior
;
3574 current_inferior
= get_lwp_thread (lwp
);
3576 lwp
->bp_reinsert
= pc
;
3577 uninsert_breakpoints_at (pc
);
3578 uninsert_fast_tracepoint_jumps_at (pc
);
3580 if (can_hardware_single_step ())
3586 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3587 set_reinsert_breakpoint (raddr
);
3591 current_inferior
= saved_inferior
;
3593 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3595 /* Require next event from this LWP. */
3596 step_over_bkpt
= lwp
->head
.id
;
3600 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3601 start_step_over, if still there, and delete any reinsert
3602 breakpoints we've set, on non hardware single-step targets. */
3605 finish_step_over (struct lwp_info
*lwp
)
3607 if (lwp
->bp_reinsert
!= 0)
3610 fprintf (stderr
, "Finished step over.\n");
3612 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3613 may be no breakpoint to reinsert there by now. */
3614 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3615 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3617 lwp
->bp_reinsert
= 0;
3619 /* Delete any software-single-step reinsert breakpoints. No
3620 longer needed. We don't have to worry about other threads
3621 hitting this trap, and later not being able to explain it,
3622 because we were stepping over a breakpoint, and we hold all
3623 threads but LWP stopped while doing that. */
3624 if (!can_hardware_single_step ())
3625 delete_reinsert_breakpoints ();
3627 step_over_bkpt
= null_ptid
;
3634 /* This function is called once per thread. We check the thread's resume
3635 request, which will tell us whether to resume, step, or leave the thread
3636 stopped; and what signal, if any, it should be sent.
3638 For threads which we aren't explicitly told otherwise, we preserve
3639 the stepping flag; this is used for stepping over gdbserver-placed
3642 If pending_flags was set in any thread, we queue any needed
3643 signals, since we won't actually resume. We already have a pending
3644 event to report, so we don't need to preserve any step requests;
3645 they should be re-issued if necessary. */
3648 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3650 struct lwp_info
*lwp
;
3651 struct thread_info
*thread
;
3653 int leave_all_stopped
= * (int *) arg
;
3656 thread
= (struct thread_info
*) entry
;
3657 lwp
= get_thread_lwp (thread
);
3659 if (lwp
->resume
== NULL
)
3662 if (lwp
->resume
->kind
== resume_stop
)
3665 fprintf (stderr
, "resume_stop request for LWP %ld\n", lwpid_of (lwp
));
3670 fprintf (stderr
, "stopping LWP %ld\n", lwpid_of (lwp
));
3672 /* Stop the thread, and wait for the event asynchronously,
3673 through the event loop. */
3679 fprintf (stderr
, "already stopped LWP %ld\n",
3682 /* The LWP may have been stopped in an internal event that
3683 was not meant to be notified back to GDB (e.g., gdbserver
3684 breakpoint), so we should be reporting a stop event in
3687 /* If the thread already has a pending SIGSTOP, this is a
3688 no-op. Otherwise, something later will presumably resume
3689 the thread and this will cause it to cancel any pending
3690 operation, due to last_resume_kind == resume_stop. If
3691 the thread already has a pending status to report, we
3692 will still report it the next time we wait - see
3693 status_pending_p_callback. */
3695 /* If we already have a pending signal to report, then
3696 there's no need to queue a SIGSTOP, as this means we're
3697 midway through moving the LWP out of the jumppad, and we
3698 will report the pending signal as soon as that is
3700 if (lwp
->pending_signals_to_report
== NULL
)
3704 /* For stop requests, we're done. */
3706 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3710 /* If this thread which is about to be resumed has a pending status,
3711 then don't resume any threads - we can just report the pending
3712 status. Make sure to queue any signals that would otherwise be
3713 sent. In all-stop mode, we do this decision based on if *any*
3714 thread has a pending status. If there's a thread that needs the
3715 step-over-breakpoint dance, then don't resume any other thread
3716 but that particular one. */
3717 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
3722 fprintf (stderr
, "resuming LWP %ld\n", lwpid_of (lwp
));
3724 step
= (lwp
->resume
->kind
== resume_step
);
3725 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
3730 fprintf (stderr
, "leaving LWP %ld stopped\n", lwpid_of (lwp
));
3732 /* If we have a new signal, enqueue the signal. */
3733 if (lwp
->resume
->sig
!= 0)
3735 struct pending_signals
*p_sig
;
3736 p_sig
= xmalloc (sizeof (*p_sig
));
3737 p_sig
->prev
= lwp
->pending_signals
;
3738 p_sig
->signal
= lwp
->resume
->sig
;
3739 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3741 /* If this is the same signal we were previously stopped by,
3742 make sure to queue its siginfo. We can ignore the return
3743 value of ptrace; if it fails, we'll skip
3744 PTRACE_SETSIGINFO. */
3745 if (WIFSTOPPED (lwp
->last_status
)
3746 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
3747 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
3750 lwp
->pending_signals
= p_sig
;
3754 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3760 linux_resume (struct thread_resume
*resume_info
, size_t n
)
3762 struct thread_resume_array array
= { resume_info
, n
};
3763 struct lwp_info
*need_step_over
= NULL
;
3765 int leave_all_stopped
;
3767 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
3769 /* If there is a thread which would otherwise be resumed, which has
3770 a pending status, then don't resume any threads - we can just
3771 report the pending status. Make sure to queue any signals that
3772 would otherwise be sent. In non-stop mode, we'll apply this
3773 logic to each thread individually. We consume all pending events
3774 before considering to start a step-over (in all-stop). */
3777 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
3779 /* If there is a thread which would otherwise be resumed, which is
3780 stopped at a breakpoint that needs stepping over, then don't
3781 resume any threads - have it step over the breakpoint with all
3782 other threads stopped, then resume all threads again. Make sure
3783 to queue any signals that would otherwise be delivered or
3785 if (!any_pending
&& supports_breakpoints ())
3787 = (struct lwp_info
*) find_inferior (&all_lwps
,
3788 need_step_over_p
, NULL
);
3790 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
3794 if (need_step_over
!= NULL
)
3795 fprintf (stderr
, "Not resuming all, need step over\n");
3796 else if (any_pending
)
3798 "Not resuming, all-stop and found "
3799 "an LWP with pending status\n");
3801 fprintf (stderr
, "Resuming, no pending status or step over needed\n");
3804 /* Even if we're leaving threads stopped, queue all signals we'd
3805 otherwise deliver. */
3806 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
3809 start_step_over (need_step_over
);
3812 /* This function is called once per thread. We check the thread's
3813 last resume request, which will tell us whether to resume, step, or
3814 leave the thread stopped. Any signal the client requested to be
3815 delivered has already been enqueued at this point.
3817 If any thread that GDB wants running is stopped at an internal
3818 breakpoint that needs stepping over, we start a step-over operation
3819 on that particular thread, and leave all others stopped. */
3822 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3824 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3825 struct thread_info
*thread
;
3833 "proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
3838 fprintf (stderr
, " LWP %ld already running\n", lwpid_of (lwp
));
3842 thread
= get_lwp_thread (lwp
);
3844 if (thread
->last_resume_kind
== resume_stop
3845 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
3848 fprintf (stderr
, " client wants LWP to remain %ld stopped\n",
3853 if (lwp
->status_pending_p
)
3856 fprintf (stderr
, " LWP %ld has pending status, leaving stopped\n",
3861 gdb_assert (lwp
->suspended
>= 0);
3866 fprintf (stderr
, " LWP %ld is suspended\n", lwpid_of (lwp
));
3870 if (thread
->last_resume_kind
== resume_stop
3871 && lwp
->pending_signals_to_report
== NULL
3872 && lwp
->collecting_fast_tracepoint
== 0)
3874 /* We haven't reported this LWP as stopped yet (otherwise, the
3875 last_status.kind check above would catch it, and we wouldn't
3876 reach here. This LWP may have been momentarily paused by a
3877 stop_all_lwps call while handling for example, another LWP's
3878 step-over. In that case, the pending expected SIGSTOP signal
3879 that was queued at vCont;t handling time will have already
3880 been consumed by wait_for_sigstop, and so we need to requeue
3881 another one here. Note that if the LWP already has a SIGSTOP
3882 pending, this is a no-op. */
3886 "Client wants LWP %ld to stop. "
3887 "Making sure it has a SIGSTOP pending\n",
3893 step
= thread
->last_resume_kind
== resume_step
;
3894 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3899 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3901 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3907 gdb_assert (lwp
->suspended
>= 0);
3909 return proceed_one_lwp (entry
, except
);
3912 /* When we finish a step-over, set threads running again. If there's
3913 another thread that may need a step-over, now's the time to start
3914 it. Eventually, we'll move all threads past their breakpoints. */
3917 proceed_all_lwps (void)
3919 struct lwp_info
*need_step_over
;
3921 /* If there is a thread which would otherwise be resumed, which is
3922 stopped at a breakpoint that needs stepping over, then don't
3923 resume any threads - have it step over the breakpoint with all
3924 other threads stopped, then resume all threads again. */
3926 if (supports_breakpoints ())
3929 = (struct lwp_info
*) find_inferior (&all_lwps
,
3930 need_step_over_p
, NULL
);
3932 if (need_step_over
!= NULL
)
3935 fprintf (stderr
, "proceed_all_lwps: found "
3936 "thread %ld needing a step-over\n",
3937 lwpid_of (need_step_over
));
3939 start_step_over (need_step_over
);
3945 fprintf (stderr
, "Proceeding, no step-over needed\n");
3947 find_inferior (&all_lwps
, proceed_one_lwp
, NULL
);
3950 /* Stopped LWPs that the client wanted to be running, that don't have
3951 pending statuses, are set to run again, except for EXCEPT, if not
3952 NULL. This undoes a stop_all_lwps call. */
3955 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
3961 "unstopping all lwps, except=(LWP %ld)\n", lwpid_of (except
));
3964 "unstopping all lwps\n");
3968 find_inferior (&all_lwps
, unsuspend_and_proceed_one_lwp
, except
);
3970 find_inferior (&all_lwps
, proceed_one_lwp
, except
);
3974 #ifdef HAVE_LINUX_REGSETS
3976 #define use_linux_regsets 1
3978 /* Returns true if REGSET has been disabled. */
3981 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
3983 return (info
->disabled_regsets
!= NULL
3984 && info
->disabled_regsets
[regset
- info
->regsets
]);
3987 /* Disable REGSET. */
3990 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
3994 dr_offset
= regset
- info
->regsets
;
3995 if (info
->disabled_regsets
== NULL
)
3996 info
->disabled_regsets
= xcalloc (1, info
->num_regsets
);
3997 info
->disabled_regsets
[dr_offset
] = 1;
4001 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
4002 struct regcache
*regcache
)
4004 struct regset_info
*regset
;
4005 int saw_general_regs
= 0;
4009 regset
= regsets_info
->regsets
;
4011 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4012 while (regset
->size
>= 0)
4017 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
4023 buf
= xmalloc (regset
->size
);
4025 nt_type
= regset
->nt_type
;
4029 iov
.iov_len
= regset
->size
;
4030 data
= (void *) &iov
;
4036 res
= ptrace (regset
->get_request
, pid
,
4037 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4039 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4045 /* If we get EIO on a regset, do not try it again for
4046 this process mode. */
4047 disable_regset (regsets_info
, regset
);
4054 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4059 else if (regset
->type
== GENERAL_REGS
)
4060 saw_general_regs
= 1;
4061 regset
->store_function (regcache
, buf
);
4065 if (saw_general_regs
)
4072 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
4073 struct regcache
*regcache
)
4075 struct regset_info
*regset
;
4076 int saw_general_regs
= 0;
4080 regset
= regsets_info
->regsets
;
4082 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4083 while (regset
->size
>= 0)
4088 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
4094 buf
= xmalloc (regset
->size
);
4096 /* First fill the buffer with the current register set contents,
4097 in case there are any items in the kernel's regset that are
4098 not in gdbserver's regcache. */
4100 nt_type
= regset
->nt_type
;
4104 iov
.iov_len
= regset
->size
;
4105 data
= (void *) &iov
;
4111 res
= ptrace (regset
->get_request
, pid
,
4112 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4114 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4119 /* Then overlay our cached registers on that. */
4120 regset
->fill_function (regcache
, buf
);
4122 /* Only now do we write the register set. */
4124 res
= ptrace (regset
->set_request
, pid
,
4125 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4127 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4135 /* If we get EIO on a regset, do not try it again for
4136 this process mode. */
4137 disable_regset (regsets_info
, regset
);
4141 else if (errno
== ESRCH
)
4143 /* At this point, ESRCH should mean the process is
4144 already gone, in which case we simply ignore attempts
4145 to change its registers. See also the related
4146 comment in linux_resume_one_lwp. */
4152 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4155 else if (regset
->type
== GENERAL_REGS
)
4156 saw_general_regs
= 1;
4160 if (saw_general_regs
)
4166 #else /* !HAVE_LINUX_REGSETS */
4168 #define use_linux_regsets 0
4169 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
4170 #define regsets_store_inferior_registers(regsets_info, regcache) 1
4174 /* Return 1 if register REGNO is supported by one of the regset ptrace
4175 calls or 0 if it has to be transferred individually. */
4178 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
4180 unsigned char mask
= 1 << (regno
% 8);
4181 size_t index
= regno
/ 8;
4183 return (use_linux_regsets
4184 && (regs_info
->regset_bitmap
== NULL
4185 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
4188 #ifdef HAVE_LINUX_USRREGS
4191 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
4195 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
4196 error ("Invalid register number %d.", regnum
);
4198 addr
= usrregs
->regmap
[regnum
];
4203 /* Fetch one register. */
4205 fetch_register (const struct usrregs_info
*usrregs
,
4206 struct regcache
*regcache
, int regno
)
4213 if (regno
>= usrregs
->num_regs
)
4215 if ((*the_low_target
.cannot_fetch_register
) (regno
))
4218 regaddr
= register_addr (usrregs
, regno
);
4222 size
= ((register_size (regcache
->tdesc
, regno
)
4223 + sizeof (PTRACE_XFER_TYPE
) - 1)
4224 & -sizeof (PTRACE_XFER_TYPE
));
4225 buf
= alloca (size
);
4227 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4228 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4231 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
4232 ptrace (PTRACE_PEEKUSER
, pid
,
4233 /* Coerce to a uintptr_t first to avoid potential gcc warning
4234 of coercing an 8 byte integer to a 4 byte pointer. */
4235 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
4236 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4238 error ("reading register %d: %s", regno
, strerror (errno
));
4241 if (the_low_target
.supply_ptrace_register
)
4242 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
4244 supply_register (regcache
, regno
, buf
);
4247 /* Store one register. */
4249 store_register (const struct usrregs_info
*usrregs
,
4250 struct regcache
*regcache
, int regno
)
4257 if (regno
>= usrregs
->num_regs
)
4259 if ((*the_low_target
.cannot_store_register
) (regno
))
4262 regaddr
= register_addr (usrregs
, regno
);
4266 size
= ((register_size (regcache
->tdesc
, regno
)
4267 + sizeof (PTRACE_XFER_TYPE
) - 1)
4268 & -sizeof (PTRACE_XFER_TYPE
));
4269 buf
= alloca (size
);
4270 memset (buf
, 0, size
);
4272 if (the_low_target
.collect_ptrace_register
)
4273 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
4275 collect_register (regcache
, regno
, buf
);
4277 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4278 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4281 ptrace (PTRACE_POKEUSER
, pid
,
4282 /* Coerce to a uintptr_t first to avoid potential gcc warning
4283 about coercing an 8 byte integer to a 4 byte pointer. */
4284 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
4285 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
4288 /* At this point, ESRCH should mean the process is
4289 already gone, in which case we simply ignore attempts
4290 to change its registers. See also the related
4291 comment in linux_resume_one_lwp. */
4295 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
4296 error ("writing register %d: %s", regno
, strerror (errno
));
4298 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4302 /* Fetch all registers, or just one, from the child process.
4303 If REGNO is -1, do this for all registers, skipping any that are
4304 assumed to have been retrieved by regsets_fetch_inferior_registers,
4305 unless ALL is non-zero.
4306 Otherwise, REGNO specifies which register (so we can save time). */
4308 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
4309 struct regcache
*regcache
, int regno
, int all
)
4311 struct usrregs_info
*usr
= regs_info
->usrregs
;
4315 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4316 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4317 fetch_register (usr
, regcache
, regno
);
4320 fetch_register (usr
, regcache
, regno
);
4323 /* Store our register values back into the inferior.
4324 If REGNO is -1, do this for all registers, skipping any that are
4325 assumed to have been saved by regsets_store_inferior_registers,
4326 unless ALL is non-zero.
4327 Otherwise, REGNO specifies which register (so we can save time). */
4329 usr_store_inferior_registers (const struct regs_info
*regs_info
,
4330 struct regcache
*regcache
, int regno
, int all
)
4332 struct usrregs_info
*usr
= regs_info
->usrregs
;
4336 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4337 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4338 store_register (usr
, regcache
, regno
);
4341 store_register (usr
, regcache
, regno
);
4344 #else /* !HAVE_LINUX_USRREGS */
4346 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4347 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4353 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4357 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
4361 if (the_low_target
.fetch_register
!= NULL
4362 && regs_info
->usrregs
!= NULL
)
4363 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
4364 (*the_low_target
.fetch_register
) (regcache
, regno
);
4366 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
4367 if (regs_info
->usrregs
!= NULL
)
4368 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
4372 if (the_low_target
.fetch_register
!= NULL
4373 && (*the_low_target
.fetch_register
) (regcache
, regno
))
4376 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
4378 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
4380 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
4381 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
4386 linux_store_registers (struct regcache
*regcache
, int regno
)
4390 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
4394 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
4396 if (regs_info
->usrregs
!= NULL
)
4397 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
4401 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
4403 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
4405 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
4406 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
4411 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4412 to debugger memory starting at MYADDR. */
4415 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4417 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4418 register PTRACE_XFER_TYPE
*buffer
;
4419 register CORE_ADDR addr
;
4426 /* Try using /proc. Don't bother for one word. */
4427 if (len
>= 3 * sizeof (long))
4431 /* We could keep this file open and cache it - possibly one per
4432 thread. That requires some juggling, but is even faster. */
4433 sprintf (filename
, "/proc/%d/mem", pid
);
4434 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4438 /* If pread64 is available, use it. It's faster if the kernel
4439 supports it (only one syscall), and it's 64-bit safe even on
4440 32-bit platforms (for instance, SPARC debugging a SPARC64
4443 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
4446 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
4447 bytes
= read (fd
, myaddr
, len
);
4454 /* Some data was read, we'll try to get the rest with ptrace. */
4464 /* Round starting address down to longword boundary. */
4465 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4466 /* Round ending address up; get number of longwords that makes. */
4467 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4468 / sizeof (PTRACE_XFER_TYPE
));
4469 /* Allocate buffer of that many longwords. */
4470 buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4472 /* Read all the longwords */
4474 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4476 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4477 about coercing an 8 byte integer to a 4 byte pointer. */
4478 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4479 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4480 (PTRACE_TYPE_ARG4
) 0);
4486 /* Copy appropriate bytes out of the buffer. */
4489 i
*= sizeof (PTRACE_XFER_TYPE
);
4490 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
4492 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4499 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4500 memory at MEMADDR. On failure (cannot write to the inferior)
4501 returns the value of errno. Always succeeds if LEN is zero. */
4504 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4507 /* Round starting address down to longword boundary. */
4508 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4509 /* Round ending address up; get number of longwords that makes. */
4511 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4512 / sizeof (PTRACE_XFER_TYPE
);
4514 /* Allocate buffer of that many longwords. */
4515 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4516 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4518 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4522 /* Zero length write always succeeds. */
4528 /* Dump up to four bytes. */
4529 unsigned int val
= * (unsigned int *) myaddr
;
4535 val
= val
& 0xffffff;
4536 fprintf (stderr
, "Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4537 val
, (long)memaddr
);
4540 /* Fill start and end extra bytes of buffer with existing memory data. */
4543 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4544 about coercing an 8 byte integer to a 4 byte pointer. */
4545 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4546 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4547 (PTRACE_TYPE_ARG4
) 0);
4555 = ptrace (PTRACE_PEEKTEXT
, pid
,
4556 /* Coerce to a uintptr_t first to avoid potential gcc warning
4557 about coercing an 8 byte integer to a 4 byte pointer. */
4558 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
4559 * sizeof (PTRACE_XFER_TYPE
)),
4560 (PTRACE_TYPE_ARG4
) 0);
4565 /* Copy data to be written over corresponding part of buffer. */
4567 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4570 /* Write the entire buffer. */
4572 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4575 ptrace (PTRACE_POKETEXT
, pid
,
4576 /* Coerce to a uintptr_t first to avoid potential gcc warning
4577 about coercing an 8 byte integer to a 4 byte pointer. */
4578 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4579 (PTRACE_TYPE_ARG4
) buffer
[i
]);
4588 linux_look_up_symbols (void)
4590 #ifdef USE_THREAD_DB
4591 struct process_info
*proc
= current_process ();
4593 if (proc
->private->thread_db
!= NULL
)
4596 /* If the kernel supports tracing clones, then we don't need to
4597 use the magic thread event breakpoint to learn about
4599 thread_db_init (!linux_supports_traceclone ());
4604 linux_request_interrupt (void)
4606 extern unsigned long signal_pid
;
4608 if (!ptid_equal (cont_thread
, null_ptid
)
4609 && !ptid_equal (cont_thread
, minus_one_ptid
))
4611 struct lwp_info
*lwp
;
4614 lwp
= get_thread_lwp (current_inferior
);
4615 lwpid
= lwpid_of (lwp
);
4616 kill_lwp (lwpid
, SIGINT
);
4619 kill_lwp (signal_pid
, SIGINT
);
4622 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4623 to debugger memory starting at MYADDR. */
4626 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4628 char filename
[PATH_MAX
];
4630 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4632 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4634 fd
= open (filename
, O_RDONLY
);
4638 if (offset
!= (CORE_ADDR
) 0
4639 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4642 n
= read (fd
, myaddr
, len
);
4649 /* These breakpoint and watchpoint related wrapper functions simply
4650 pass on the function call if the target has registered a
4651 corresponding function. */
4654 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
4656 if (the_low_target
.insert_point
!= NULL
)
4657 return the_low_target
.insert_point (type
, addr
, len
);
4659 /* Unsupported (see target.h). */
4664 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
4666 if (the_low_target
.remove_point
!= NULL
)
4667 return the_low_target
.remove_point (type
, addr
, len
);
4669 /* Unsupported (see target.h). */
4674 linux_stopped_by_watchpoint (void)
4676 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4678 return lwp
->stopped_by_watchpoint
;
4682 linux_stopped_data_address (void)
4684 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4686 return lwp
->stopped_data_address
;
4689 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
4690 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
4691 && defined(PT_TEXT_END_ADDR)
4693 /* This is only used for targets that define PT_TEXT_ADDR,
4694 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
4695 the target has different ways of acquiring this information, like
4698 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4699 to tell gdb about. */
4702 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
4704 unsigned long text
, text_end
, data
;
4705 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4709 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
4710 (PTRACE_TYPE_ARG4
) 0);
4711 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
4712 (PTRACE_TYPE_ARG4
) 0);
4713 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
4714 (PTRACE_TYPE_ARG4
) 0);
4718 /* Both text and data offsets produced at compile-time (and so
4719 used by gdb) are relative to the beginning of the program,
4720 with the data segment immediately following the text segment.
4721 However, the actual runtime layout in memory may put the data
4722 somewhere else, so when we send gdb a data base-address, we
4723 use the real data base address and subtract the compile-time
4724 data base-address from it (which is just the length of the
4725 text segment). BSS immediately follows data in both
4728 *data_p
= data
- (text_end
- text
);
4737 linux_qxfer_osdata (const char *annex
,
4738 unsigned char *readbuf
, unsigned const char *writebuf
,
4739 CORE_ADDR offset
, int len
)
4741 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
4744 /* Convert a native/host siginfo object, into/from the siginfo in the
4745 layout of the inferiors' architecture. */
4748 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
4752 if (the_low_target
.siginfo_fixup
!= NULL
)
4753 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4755 /* If there was no callback, or the callback didn't do anything,
4756 then just do a straight memcpy. */
4760 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
4762 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
4767 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
4768 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
4772 char inf_siginfo
[sizeof (siginfo_t
)];
4774 if (current_inferior
== NULL
)
4777 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4780 fprintf (stderr
, "%s siginfo for lwp %d.\n",
4781 readbuf
!= NULL
? "Reading" : "Writing",
4784 if (offset
>= sizeof (siginfo
))
4787 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
4790 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4791 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4792 inferior with a 64-bit GDBSERVER should look the same as debugging it
4793 with a 32-bit GDBSERVER, we need to convert it. */
4794 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4796 if (offset
+ len
> sizeof (siginfo
))
4797 len
= sizeof (siginfo
) - offset
;
4799 if (readbuf
!= NULL
)
4800 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4803 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4805 /* Convert back to ptrace layout before flushing it out. */
4806 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4808 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
4815 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4816 so we notice when children change state; as the handler for the
4817 sigsuspend in my_waitpid. */
4820 sigchld_handler (int signo
)
4822 int old_errno
= errno
;
4828 /* fprintf is not async-signal-safe, so call write
4830 if (write (2, "sigchld_handler\n",
4831 sizeof ("sigchld_handler\n") - 1) < 0)
4832 break; /* just ignore */
4836 if (target_is_async_p ())
4837 async_file_mark (); /* trigger a linux_wait */
4843 linux_supports_non_stop (void)
4849 linux_async (int enable
)
4851 int previous
= (linux_event_pipe
[0] != -1);
4854 fprintf (stderr
, "linux_async (%d), previous=%d\n",
4857 if (previous
!= enable
)
4860 sigemptyset (&mask
);
4861 sigaddset (&mask
, SIGCHLD
);
4863 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
4867 if (pipe (linux_event_pipe
) == -1)
4868 fatal ("creating event pipe failed.");
4870 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
4871 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
4873 /* Register the event loop handler. */
4874 add_file_handler (linux_event_pipe
[0],
4875 handle_target_event
, NULL
);
4877 /* Always trigger a linux_wait. */
4882 delete_file_handler (linux_event_pipe
[0]);
4884 close (linux_event_pipe
[0]);
4885 close (linux_event_pipe
[1]);
4886 linux_event_pipe
[0] = -1;
4887 linux_event_pipe
[1] = -1;
4890 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
4897 linux_start_non_stop (int nonstop
)
4899 /* Register or unregister from event-loop accordingly. */
4900 linux_async (nonstop
);
4905 linux_supports_multi_process (void)
4911 linux_supports_disable_randomization (void)
4913 #ifdef HAVE_PERSONALITY
4921 linux_supports_agent (void)
4927 linux_supports_range_stepping (void)
4929 if (*the_low_target
.supports_range_stepping
== NULL
)
4932 return (*the_low_target
.supports_range_stepping
) ();
4935 /* Enumerate spufs IDs for process PID. */
4937 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
4943 struct dirent
*entry
;
4945 sprintf (path
, "/proc/%ld/fd", pid
);
4946 dir
= opendir (path
);
4951 while ((entry
= readdir (dir
)) != NULL
)
4957 fd
= atoi (entry
->d_name
);
4961 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
4962 if (stat (path
, &st
) != 0)
4964 if (!S_ISDIR (st
.st_mode
))
4967 if (statfs (path
, &stfs
) != 0)
4969 if (stfs
.f_type
!= SPUFS_MAGIC
)
4972 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
4974 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
4984 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
4985 object type, using the /proc file system. */
4987 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
4988 unsigned const char *writebuf
,
4989 CORE_ADDR offset
, int len
)
4991 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
4996 if (!writebuf
&& !readbuf
)
5004 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5007 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
5008 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5013 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5020 ret
= write (fd
, writebuf
, (size_t) len
);
5022 ret
= read (fd
, readbuf
, (size_t) len
);
5028 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5029 struct target_loadseg
5031 /* Core address to which the segment is mapped. */
5033 /* VMA recorded in the program header. */
5035 /* Size of this segment in memory. */
5039 # if defined PT_GETDSBT
5040 struct target_loadmap
5042 /* Protocol version number, must be zero. */
5044 /* Pointer to the DSBT table, its size, and the DSBT index. */
5045 unsigned *dsbt_table
;
5046 unsigned dsbt_size
, dsbt_index
;
5047 /* Number of segments in this map. */
5049 /* The actual memory map. */
5050 struct target_loadseg segs
[/*nsegs*/];
5052 # define LINUX_LOADMAP PT_GETDSBT
5053 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5054 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5056 struct target_loadmap
5058 /* Protocol version number, must be zero. */
5060 /* Number of segments in this map. */
5062 /* The actual memory map. */
5063 struct target_loadseg segs
[/*nsegs*/];
5065 # define LINUX_LOADMAP PTRACE_GETFDPIC
5066 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5067 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5071 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
5072 unsigned char *myaddr
, unsigned int len
)
5074 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
5076 struct target_loadmap
*data
= NULL
;
5077 unsigned int actual_length
, copy_length
;
5079 if (strcmp (annex
, "exec") == 0)
5080 addr
= (int) LINUX_LOADMAP_EXEC
;
5081 else if (strcmp (annex
, "interp") == 0)
5082 addr
= (int) LINUX_LOADMAP_INTERP
;
5086 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
5092 actual_length
= sizeof (struct target_loadmap
)
5093 + sizeof (struct target_loadseg
) * data
->nsegs
;
5095 if (offset
< 0 || offset
> actual_length
)
5098 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
5099 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
5103 # define linux_read_loadmap NULL
5104 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5107 linux_process_qsupported (const char *query
)
5109 if (the_low_target
.process_qsupported
!= NULL
)
5110 the_low_target
.process_qsupported (query
);
5114 linux_supports_tracepoints (void)
5116 if (*the_low_target
.supports_tracepoints
== NULL
)
5119 return (*the_low_target
.supports_tracepoints
) ();
5123 linux_read_pc (struct regcache
*regcache
)
5125 if (the_low_target
.get_pc
== NULL
)
5128 return (*the_low_target
.get_pc
) (regcache
);
5132 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
5134 gdb_assert (the_low_target
.set_pc
!= NULL
);
5136 (*the_low_target
.set_pc
) (regcache
, pc
);
5140 linux_thread_stopped (struct thread_info
*thread
)
5142 return get_thread_lwp (thread
)->stopped
;
5145 /* This exposes stop-all-threads functionality to other modules. */
5148 linux_pause_all (int freeze
)
5150 stop_all_lwps (freeze
, NULL
);
5153 /* This exposes unstop-all-threads functionality to other gdbserver
5157 linux_unpause_all (int unfreeze
)
5159 unstop_all_lwps (unfreeze
, NULL
);
5163 linux_prepare_to_access_memory (void)
5165 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5168 linux_pause_all (1);
5173 linux_done_accessing_memory (void)
5175 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5178 linux_unpause_all (1);
5182 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5183 CORE_ADDR collector
,
5186 CORE_ADDR
*jump_entry
,
5187 CORE_ADDR
*trampoline
,
5188 ULONGEST
*trampoline_size
,
5189 unsigned char *jjump_pad_insn
,
5190 ULONGEST
*jjump_pad_insn_size
,
5191 CORE_ADDR
*adjusted_insn_addr
,
5192 CORE_ADDR
*adjusted_insn_addr_end
,
5195 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5196 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5197 jump_entry
, trampoline
, trampoline_size
,
5198 jjump_pad_insn
, jjump_pad_insn_size
,
5199 adjusted_insn_addr
, adjusted_insn_addr_end
,
5203 static struct emit_ops
*
5204 linux_emit_ops (void)
5206 if (the_low_target
.emit_ops
!= NULL
)
5207 return (*the_low_target
.emit_ops
) ();
5213 linux_get_min_fast_tracepoint_insn_len (void)
5215 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5218 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5221 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5222 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5224 char filename
[PATH_MAX
];
5226 const int auxv_size
= is_elf64
5227 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5228 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5230 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5232 fd
= open (filename
, O_RDONLY
);
5238 while (read (fd
, buf
, auxv_size
) == auxv_size
5239 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5243 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5245 switch (aux
->a_type
)
5248 *phdr_memaddr
= aux
->a_un
.a_val
;
5251 *num_phdr
= aux
->a_un
.a_val
;
5257 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5259 switch (aux
->a_type
)
5262 *phdr_memaddr
= aux
->a_un
.a_val
;
5265 *num_phdr
= aux
->a_un
.a_val
;
5273 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5275 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5276 "phdr_memaddr = %ld, phdr_num = %d",
5277 (long) *phdr_memaddr
, *num_phdr
);
5284 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5287 get_dynamic (const int pid
, const int is_elf64
)
5289 CORE_ADDR phdr_memaddr
, relocation
;
5291 unsigned char *phdr_buf
;
5292 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5294 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5297 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5298 phdr_buf
= alloca (num_phdr
* phdr_size
);
5300 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5303 /* Compute relocation: it is expected to be 0 for "regular" executables,
5304 non-zero for PIE ones. */
5306 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5309 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5311 if (p
->p_type
== PT_PHDR
)
5312 relocation
= phdr_memaddr
- p
->p_vaddr
;
5316 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5318 if (p
->p_type
== PT_PHDR
)
5319 relocation
= phdr_memaddr
- p
->p_vaddr
;
5322 if (relocation
== -1)
5324 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5325 any real world executables, including PIE executables, have always
5326 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5327 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5328 or present DT_DEBUG anyway (fpc binaries are statically linked).
5330 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5332 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5337 for (i
= 0; i
< num_phdr
; i
++)
5341 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5343 if (p
->p_type
== PT_DYNAMIC
)
5344 return p
->p_vaddr
+ relocation
;
5348 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5350 if (p
->p_type
== PT_DYNAMIC
)
5351 return p
->p_vaddr
+ relocation
;
5358 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5359 can be 0 if the inferior does not yet have the library list initialized.
5360 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
5361 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
5364 get_r_debug (const int pid
, const int is_elf64
)
5366 CORE_ADDR dynamic_memaddr
;
5367 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5368 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5371 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5372 if (dynamic_memaddr
== 0)
5375 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5379 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5380 #ifdef DT_MIPS_RLD_MAP
5384 unsigned char buf
[sizeof (Elf64_Xword
)];
5388 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5390 if (linux_read_memory (dyn
->d_un
.d_val
,
5391 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5396 #endif /* DT_MIPS_RLD_MAP */
5398 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5399 map
= dyn
->d_un
.d_val
;
5401 if (dyn
->d_tag
== DT_NULL
)
5406 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5407 #ifdef DT_MIPS_RLD_MAP
5411 unsigned char buf
[sizeof (Elf32_Word
)];
5415 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5417 if (linux_read_memory (dyn
->d_un
.d_val
,
5418 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5423 #endif /* DT_MIPS_RLD_MAP */
5425 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5426 map
= dyn
->d_un
.d_val
;
5428 if (dyn
->d_tag
== DT_NULL
)
5432 dynamic_memaddr
+= dyn_size
;
5438 /* Read one pointer from MEMADDR in the inferior. */
5441 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5445 /* Go through a union so this works on either big or little endian
5446 hosts, when the inferior's pointer size is smaller than the size
5447 of CORE_ADDR. It is assumed the inferior's endianness is the
5448 same of the superior's. */
5451 CORE_ADDR core_addr
;
5456 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
5459 if (ptr_size
== sizeof (CORE_ADDR
))
5460 *ptr
= addr
.core_addr
;
5461 else if (ptr_size
== sizeof (unsigned int))
5464 gdb_assert_not_reached ("unhandled pointer size");
5469 struct link_map_offsets
5471 /* Offset and size of r_debug.r_version. */
5472 int r_version_offset
;
5474 /* Offset and size of r_debug.r_map. */
5477 /* Offset to l_addr field in struct link_map. */
5480 /* Offset to l_name field in struct link_map. */
5483 /* Offset to l_ld field in struct link_map. */
5486 /* Offset to l_next field in struct link_map. */
5489 /* Offset to l_prev field in struct link_map. */
5493 /* Construct qXfer:libraries-svr4:read reply. */
5496 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5497 unsigned const char *writebuf
,
5498 CORE_ADDR offset
, int len
)
5501 unsigned document_len
;
5502 struct process_info_private
*const priv
= current_process ()->private;
5503 char filename
[PATH_MAX
];
5506 static const struct link_map_offsets lmo_32bit_offsets
=
5508 0, /* r_version offset. */
5509 4, /* r_debug.r_map offset. */
5510 0, /* l_addr offset in link_map. */
5511 4, /* l_name offset in link_map. */
5512 8, /* l_ld offset in link_map. */
5513 12, /* l_next offset in link_map. */
5514 16 /* l_prev offset in link_map. */
5517 static const struct link_map_offsets lmo_64bit_offsets
=
5519 0, /* r_version offset. */
5520 8, /* r_debug.r_map offset. */
5521 0, /* l_addr offset in link_map. */
5522 8, /* l_name offset in link_map. */
5523 16, /* l_ld offset in link_map. */
5524 24, /* l_next offset in link_map. */
5525 32 /* l_prev offset in link_map. */
5527 const struct link_map_offsets
*lmo
;
5528 unsigned int machine
;
5530 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
5531 int allocated
= 1024;
5533 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5534 int header_done
= 0;
5536 if (writebuf
!= NULL
)
5538 if (readbuf
== NULL
)
5541 pid
= lwpid_of (get_thread_lwp (current_inferior
));
5542 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5543 is_elf64
= elf_64_file_p (filename
, &machine
);
5544 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5545 ptr_size
= is_elf64
? 8 : 4;
5547 while (annex
[0] != '\0')
5553 sep
= strchr (annex
, '=');
5558 if (len
== 5 && strncmp (annex
, "start", 5) == 0)
5560 else if (len
== 4 && strncmp (annex
, "prev", 4) == 0)
5564 annex
= strchr (sep
, ';');
5571 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
5578 if (priv
->r_debug
== 0)
5579 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5581 /* We failed to find DT_DEBUG. Such situation will not change
5582 for this inferior - do not retry it. Report it to GDB as
5583 E01, see for the reasons at the GDB solib-svr4.c side. */
5584 if (priv
->r_debug
== (CORE_ADDR
) -1)
5587 if (priv
->r_debug
!= 0)
5589 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5590 (unsigned char *) &r_version
,
5591 sizeof (r_version
)) != 0
5594 warning ("unexpected r_debug version %d", r_version
);
5596 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5597 &lm_addr
, ptr_size
) != 0)
5599 warning ("unable to read r_map from 0x%lx",
5600 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5605 document
= xmalloc (allocated
);
5606 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5607 p
= document
+ strlen (document
);
5610 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5611 &l_name
, ptr_size
) == 0
5612 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5613 &l_addr
, ptr_size
) == 0
5614 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5615 &l_ld
, ptr_size
) == 0
5616 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5617 &l_prev
, ptr_size
) == 0
5618 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5619 &l_next
, ptr_size
) == 0)
5621 unsigned char libname
[PATH_MAX
];
5623 if (lm_prev
!= l_prev
)
5625 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5626 (long) lm_prev
, (long) l_prev
);
5630 /* Ignore the first entry even if it has valid name as the first entry
5631 corresponds to the main executable. The first entry should not be
5632 skipped if the dynamic loader was loaded late by a static executable
5633 (see solib-svr4.c parameter ignore_first). But in such case the main
5634 executable does not have PT_DYNAMIC present and this function already
5635 exited above due to failed get_r_debug. */
5638 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5643 /* Not checking for error because reading may stop before
5644 we've got PATH_MAX worth of characters. */
5646 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5647 libname
[sizeof (libname
) - 1] = '\0';
5648 if (libname
[0] != '\0')
5650 /* 6x the size for xml_escape_text below. */
5651 size_t len
= 6 * strlen ((char *) libname
);
5656 /* Terminate `<library-list-svr4'. */
5661 while (allocated
< p
- document
+ len
+ 200)
5663 /* Expand to guarantee sufficient storage. */
5664 uintptr_t document_len
= p
- document
;
5666 document
= xrealloc (document
, 2 * allocated
);
5668 p
= document
+ document_len
;
5671 name
= xml_escape_text ((char *) libname
);
5672 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
5673 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5674 name
, (unsigned long) lm_addr
,
5675 (unsigned long) l_addr
, (unsigned long) l_ld
);
5686 /* Empty list; terminate `<library-list-svr4'. */
5690 strcpy (p
, "</library-list-svr4>");
5692 document_len
= strlen (document
);
5693 if (offset
< document_len
)
5694 document_len
-= offset
;
5697 if (len
> document_len
)
5700 memcpy (readbuf
, document
+ offset
, len
);
5706 #ifdef HAVE_LINUX_BTRACE
5708 /* Enable branch tracing. */
5710 static struct btrace_target_info
*
5711 linux_low_enable_btrace (ptid_t ptid
)
5713 struct btrace_target_info
*tinfo
;
5715 tinfo
= linux_enable_btrace (ptid
);
5719 struct thread_info
*thread
= find_thread_ptid (ptid
);
5720 struct regcache
*regcache
= get_thread_regcache (thread
, 0);
5722 tinfo
->ptr_bits
= register_size (regcache
->tdesc
, 0) * 8;
5728 /* Read branch trace data as btrace xml document. */
5731 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
5734 VEC (btrace_block_s
) *btrace
;
5735 struct btrace_block
*block
;
5738 btrace
= linux_read_btrace (tinfo
, type
);
5740 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
5741 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
5743 for (i
= 0; VEC_iterate (btrace_block_s
, btrace
, i
, block
); i
++)
5744 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
5745 paddress (block
->begin
), paddress (block
->end
));
5747 buffer_grow_str (buffer
, "</btrace>\n");
5749 VEC_free (btrace_block_s
, btrace
);
5751 #endif /* HAVE_LINUX_BTRACE */
5753 static struct target_ops linux_target_ops
= {
5754 linux_create_inferior
,
5763 linux_fetch_registers
,
5764 linux_store_registers
,
5765 linux_prepare_to_access_memory
,
5766 linux_done_accessing_memory
,
5769 linux_look_up_symbols
,
5770 linux_request_interrupt
,
5774 linux_stopped_by_watchpoint
,
5775 linux_stopped_data_address
,
5776 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5777 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5778 && defined(PT_TEXT_END_ADDR)
5783 #ifdef USE_THREAD_DB
5784 thread_db_get_tls_address
,
5789 hostio_last_error_from_errno
,
5792 linux_supports_non_stop
,
5794 linux_start_non_stop
,
5795 linux_supports_multi_process
,
5796 #ifdef USE_THREAD_DB
5797 thread_db_handle_monitor_command
,
5801 linux_common_core_of_thread
,
5803 linux_process_qsupported
,
5804 linux_supports_tracepoints
,
5807 linux_thread_stopped
,
5811 linux_cancel_breakpoints
,
5812 linux_stabilize_threads
,
5813 linux_install_fast_tracepoint_jump_pad
,
5815 linux_supports_disable_randomization
,
5816 linux_get_min_fast_tracepoint_insn_len
,
5817 linux_qxfer_libraries_svr4
,
5818 linux_supports_agent
,
5819 #ifdef HAVE_LINUX_BTRACE
5820 linux_supports_btrace
,
5821 linux_low_enable_btrace
,
5822 linux_disable_btrace
,
5823 linux_low_read_btrace
,
5830 linux_supports_range_stepping
,
5834 linux_init_signals ()
5836 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5837 to find what the cancel signal actually is. */
5838 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
5839 signal (__SIGRTMIN
+1, SIG_IGN
);
5843 #ifdef HAVE_LINUX_REGSETS
5845 initialize_regsets_info (struct regsets_info
*info
)
5847 for (info
->num_regsets
= 0;
5848 info
->regsets
[info
->num_regsets
].size
>= 0;
5849 info
->num_regsets
++)
5855 initialize_low (void)
5857 struct sigaction sigchld_action
;
5858 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
5859 set_target_ops (&linux_target_ops
);
5860 set_breakpoint_data (the_low_target
.breakpoint
,
5861 the_low_target
.breakpoint_len
);
5862 linux_init_signals ();
5863 linux_ptrace_init_warnings ();
5865 sigchld_action
.sa_handler
= sigchld_handler
;
5866 sigemptyset (&sigchld_action
.sa_mask
);
5867 sigchld_action
.sa_flags
= SA_RESTART
;
5868 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
5870 initialize_low_arch ();