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 debug_printf ("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 debug_printf ("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
))
695 debug_printf ("Attached to a stopped process\n");
697 /* The process is definitely stopped. It is in a job control
698 stop, unless the kernel predates the TASK_STOPPED /
699 TASK_TRACED distinction, in which case it might be in a
700 ptrace stop. Make sure it is in a ptrace stop; from there we
701 can kill it, signal it, et cetera.
703 First make sure there is a pending SIGSTOP. Since we are
704 already attached, the process can not transition from stopped
705 to running without a PTRACE_CONT; so we know this signal will
706 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
707 probably already in the queue (unless this kernel is old
708 enough to use TASK_STOPPED for ptrace stops); but since
709 SIGSTOP is not an RT signal, it can only be queued once. */
710 kill_lwp (lwpid
, SIGSTOP
);
712 /* Finally, resume the stopped process. This will deliver the
713 SIGSTOP (or a higher priority signal, just like normal
714 PTRACE_ATTACH), which we'll catch later on. */
715 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
718 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
721 There are several cases to consider here:
723 1) gdbserver has already attached to the process and is being notified
724 of a new thread that is being created.
725 In this case we should ignore that SIGSTOP and resume the
726 process. This is handled below by setting stop_expected = 1,
727 and the fact that add_thread sets last_resume_kind ==
730 2) This is the first thread (the process thread), and we're attaching
731 to it via attach_inferior.
732 In this case we want the process thread to stop.
733 This is handled by having linux_attach set last_resume_kind ==
734 resume_stop after we return.
736 If the pid we are attaching to is also the tgid, we attach to and
737 stop all the existing threads. Otherwise, we attach to pid and
738 ignore any other threads in the same group as this pid.
740 3) GDB is connecting to gdbserver and is requesting an enumeration of all
742 In this case we want the thread to stop.
743 FIXME: This case is currently not properly handled.
744 We should wait for the SIGSTOP but don't. Things work apparently
745 because enough time passes between when we ptrace (ATTACH) and when
746 gdb makes the next ptrace call on the thread.
748 On the other hand, if we are currently trying to stop all threads, we
749 should treat the new thread as if we had sent it a SIGSTOP. This works
750 because we are guaranteed that the add_lwp call above added us to the
751 end of the list, and so the new thread has not yet reached
752 wait_for_sigstop (but will). */
753 new_lwp
->stop_expected
= 1;
757 linux_attach_lwp (unsigned long lwpid
)
759 linux_attach_lwp_1 (lwpid
, 0);
762 /* Attach to PID. If PID is the tgid, attach to it and all
766 linux_attach (unsigned long pid
)
768 /* Attach to PID. We will check for other threads
770 linux_attach_lwp_1 (pid
, 1);
771 linux_add_process (pid
, 1);
775 struct thread_info
*thread
;
777 /* Don't ignore the initial SIGSTOP if we just attached to this
778 process. It will be collected by wait shortly. */
779 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
780 thread
->last_resume_kind
= resume_stop
;
783 if (linux_proc_get_tgid (pid
) == pid
)
788 sprintf (pathname
, "/proc/%ld/task", pid
);
790 dir
= opendir (pathname
);
794 fprintf (stderr
, "Could not open /proc/%ld/task.\n", pid
);
799 /* At this point we attached to the tgid. Scan the task for
802 int new_threads_found
;
806 while (iterations
< 2)
808 new_threads_found
= 0;
809 /* Add all the other threads. While we go through the
810 threads, new threads may be spawned. Cycle through
811 the list of threads until we have done two iterations without
812 finding new threads. */
813 while ((dp
= readdir (dir
)) != NULL
)
816 lwp
= strtoul (dp
->d_name
, NULL
, 10);
818 /* Is this a new thread? */
820 && find_thread_ptid (ptid_build (pid
, lwp
, 0)) == NULL
)
822 linux_attach_lwp_1 (lwp
, 0);
826 debug_printf ("Found and attached to new lwp %ld\n",
831 if (!new_threads_found
)
852 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
854 struct counter
*counter
= args
;
856 if (ptid_get_pid (entry
->id
) == counter
->pid
)
858 if (++counter
->count
> 1)
866 last_thread_of_process_p (struct thread_info
*thread
)
868 ptid_t ptid
= ((struct inferior_list_entry
*)thread
)->id
;
869 int pid
= ptid_get_pid (ptid
);
870 struct counter counter
= { pid
, 0 };
872 return (find_inferior (&all_threads
,
873 second_thread_of_pid_p
, &counter
) == NULL
);
879 linux_kill_one_lwp (struct lwp_info
*lwp
)
881 int pid
= lwpid_of (lwp
);
883 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
884 there is no signal context, and ptrace(PTRACE_KILL) (or
885 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
886 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
887 alternative is to kill with SIGKILL. We only need one SIGKILL
888 per process, not one for each thread. But since we still support
889 linuxthreads, and we also support debugging programs using raw
890 clone without CLONE_THREAD, we send one for each thread. For
891 years, we used PTRACE_KILL only, so we're being a bit paranoid
892 about some old kernels where PTRACE_KILL might work better
893 (dubious if there are any such, but that's why it's paranoia), so
894 we try SIGKILL first, PTRACE_KILL second, and so we're fine
900 debug_printf ("LKL: kill (SIGKILL) %s, 0, 0 (%s)\n",
901 target_pid_to_str (ptid_of (lwp
)),
902 errno
? strerror (errno
) : "OK");
905 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
907 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
908 target_pid_to_str (ptid_of (lwp
)),
909 errno
? strerror (errno
) : "OK");
912 /* Callback for `find_inferior'. Kills an lwp of a given process,
913 except the leader. */
916 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
918 struct thread_info
*thread
= (struct thread_info
*) entry
;
919 struct lwp_info
*lwp
= get_thread_lwp (thread
);
921 int pid
= * (int *) args
;
923 if (ptid_get_pid (entry
->id
) != pid
)
926 /* We avoid killing the first thread here, because of a Linux kernel (at
927 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
928 the children get a chance to be reaped, it will remain a zombie
931 if (lwpid_of (lwp
) == pid
)
934 debug_printf ("lkop: is last of process %s\n",
935 target_pid_to_str (entry
->id
));
941 linux_kill_one_lwp (lwp
);
943 /* Make sure it died. The loop is most likely unnecessary. */
944 pid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
945 } while (pid
> 0 && WIFSTOPPED (wstat
));
953 struct process_info
*process
;
954 struct lwp_info
*lwp
;
958 process
= find_process_pid (pid
);
962 /* If we're killing a running inferior, make sure it is stopped
963 first, as PTRACE_KILL will not work otherwise. */
964 stop_all_lwps (0, NULL
);
966 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
968 /* See the comment in linux_kill_one_lwp. We did not kill the first
969 thread in the list, so do so now. */
970 lwp
= find_lwp_pid (pid_to_ptid (pid
));
975 debug_printf ("lk_1: cannot find lwp %ld, for pid: %d\n",
976 lwpid_of (lwp
), pid
);
981 debug_printf ("lk_1: killing lwp %ld, for pid: %d\n",
982 lwpid_of (lwp
), pid
);
986 linux_kill_one_lwp (lwp
);
988 /* Make sure it died. The loop is most likely unnecessary. */
989 lwpid
= linux_wait_for_event (lwp
->head
.id
, &wstat
, __WALL
);
990 } while (lwpid
> 0 && WIFSTOPPED (wstat
));
993 the_target
->mourn (process
);
995 /* Since we presently can only stop all lwps of all processes, we
996 need to unstop lwps of other processes. */
997 unstop_all_lwps (0, NULL
);
1001 /* Get pending signal of THREAD, for detaching purposes. This is the
1002 signal the thread last stopped for, which we need to deliver to the
1003 thread when detaching, otherwise, it'd be suppressed/lost. */
1006 get_detach_signal (struct thread_info
*thread
)
1008 enum gdb_signal signo
= GDB_SIGNAL_0
;
1010 struct lwp_info
*lp
= get_thread_lwp (thread
);
1012 if (lp
->status_pending_p
)
1013 status
= lp
->status_pending
;
1016 /* If the thread had been suspended by gdbserver, and it stopped
1017 cleanly, then it'll have stopped with SIGSTOP. But we don't
1018 want to deliver that SIGSTOP. */
1019 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1020 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1023 /* Otherwise, we may need to deliver the signal we
1025 status
= lp
->last_status
;
1028 if (!WIFSTOPPED (status
))
1031 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1032 target_pid_to_str (ptid_of (lp
)));
1036 /* Extended wait statuses aren't real SIGTRAPs. */
1037 if (WSTOPSIG (status
) == SIGTRAP
&& status
>> 16 != 0)
1040 debug_printf ("GPS: lwp %s had stopped with extended "
1041 "status: no pending signal\n",
1042 target_pid_to_str (ptid_of (lp
)));
1046 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1048 if (program_signals_p
&& !program_signals
[signo
])
1051 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1052 target_pid_to_str (ptid_of (lp
)),
1053 gdb_signal_to_string (signo
));
1056 else if (!program_signals_p
1057 /* If we have no way to know which signals GDB does not
1058 want to have passed to the program, assume
1059 SIGTRAP/SIGINT, which is GDB's default. */
1060 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1063 debug_printf ("GPS: lwp %s had signal %s, "
1064 "but we don't know if we should pass it. "
1065 "Default to not.\n",
1066 target_pid_to_str (ptid_of (lp
)),
1067 gdb_signal_to_string (signo
));
1073 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1074 target_pid_to_str (ptid_of (lp
)),
1075 gdb_signal_to_string (signo
));
1077 return WSTOPSIG (status
);
1082 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1084 struct thread_info
*thread
= (struct thread_info
*) entry
;
1085 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1086 int pid
= * (int *) args
;
1089 if (ptid_get_pid (entry
->id
) != pid
)
1092 /* If there is a pending SIGSTOP, get rid of it. */
1093 if (lwp
->stop_expected
)
1096 debug_printf ("Sending SIGCONT to %s\n",
1097 target_pid_to_str (ptid_of (lwp
)));
1099 kill_lwp (lwpid_of (lwp
), SIGCONT
);
1100 lwp
->stop_expected
= 0;
1103 /* Flush any pending changes to the process's registers. */
1104 regcache_invalidate_thread (get_lwp_thread (lwp
));
1106 /* Pass on any pending signal for this thread. */
1107 sig
= get_detach_signal (thread
);
1109 /* Finally, let it resume. */
1110 if (the_low_target
.prepare_to_resume
!= NULL
)
1111 the_low_target
.prepare_to_resume (lwp
);
1112 if (ptrace (PTRACE_DETACH
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
1113 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1114 error (_("Can't detach %s: %s"),
1115 target_pid_to_str (ptid_of (lwp
)),
1123 linux_detach (int pid
)
1125 struct process_info
*process
;
1127 process
= find_process_pid (pid
);
1128 if (process
== NULL
)
1131 /* Stop all threads before detaching. First, ptrace requires that
1132 the thread is stopped to sucessfully detach. Second, thread_db
1133 may need to uninstall thread event breakpoints from memory, which
1134 only works with a stopped process anyway. */
1135 stop_all_lwps (0, NULL
);
1137 #ifdef USE_THREAD_DB
1138 thread_db_detach (process
);
1141 /* Stabilize threads (move out of jump pads). */
1142 stabilize_threads ();
1144 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1146 the_target
->mourn (process
);
1148 /* Since we presently can only stop all lwps of all processes, we
1149 need to unstop lwps of other processes. */
1150 unstop_all_lwps (0, NULL
);
1154 /* Remove all LWPs that belong to process PROC from the lwp list. */
1157 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1159 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1160 struct process_info
*process
= proc
;
1162 if (pid_of (lwp
) == pid_of (process
))
1169 linux_mourn (struct process_info
*process
)
1171 struct process_info_private
*priv
;
1173 #ifdef USE_THREAD_DB
1174 thread_db_mourn (process
);
1177 find_inferior (&all_lwps
, delete_lwp_callback
, process
);
1179 /* Freeing all private data. */
1180 priv
= process
->private;
1181 free (priv
->arch_private
);
1183 process
->private = NULL
;
1185 remove_process (process
);
1189 linux_join (int pid
)
1194 ret
= my_waitpid (pid
, &status
, 0);
1195 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1197 } while (ret
!= -1 || errno
!= ECHILD
);
1200 /* Return nonzero if the given thread is still alive. */
1202 linux_thread_alive (ptid_t ptid
)
1204 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1206 /* We assume we always know if a thread exits. If a whole process
1207 exited but we still haven't been able to report it to GDB, we'll
1208 hold on to the last lwp of the dead process. */
1215 /* Return 1 if this lwp has an interesting status pending. */
1217 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1219 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
1220 ptid_t ptid
= * (ptid_t
*) arg
;
1221 struct thread_info
*thread
;
1223 /* Check if we're only interested in events from a specific process
1225 if (!ptid_equal (minus_one_ptid
, ptid
)
1226 && ptid_get_pid (ptid
) != ptid_get_pid (lwp
->head
.id
))
1229 thread
= get_lwp_thread (lwp
);
1231 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1232 report any status pending the LWP may have. */
1233 if (thread
->last_resume_kind
== resume_stop
1234 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1237 return lwp
->status_pending_p
;
1241 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1243 ptid_t ptid
= *(ptid_t
*) data
;
1246 if (ptid_get_lwp (ptid
) != 0)
1247 lwp
= ptid_get_lwp (ptid
);
1249 lwp
= ptid_get_pid (ptid
);
1251 if (ptid_get_lwp (entry
->id
) == lwp
)
1258 find_lwp_pid (ptid_t ptid
)
1260 return (struct lwp_info
*) find_inferior (&all_lwps
, same_lwp
, &ptid
);
1263 static struct lwp_info
*
1264 linux_wait_for_lwp (ptid_t ptid
, int *wstatp
, int options
)
1267 int to_wait_for
= -1;
1268 struct lwp_info
*child
= NULL
;
1271 debug_printf ("linux_wait_for_lwp: %s\n", target_pid_to_str (ptid
));
1273 if (ptid_equal (ptid
, minus_one_ptid
))
1274 to_wait_for
= -1; /* any child */
1276 to_wait_for
= ptid_get_lwp (ptid
); /* this lwp only */
1282 ret
= my_waitpid (to_wait_for
, wstatp
, options
);
1283 if (ret
== 0 || (ret
== -1 && errno
== ECHILD
&& (options
& WNOHANG
)))
1286 perror_with_name ("waitpid");
1289 && (!WIFSTOPPED (*wstatp
)
1290 || (WSTOPSIG (*wstatp
) != 32
1291 && WSTOPSIG (*wstatp
) != 33)))
1292 debug_printf ("Got an event from %d (%x)\n", ret
, *wstatp
);
1294 child
= find_lwp_pid (pid_to_ptid (ret
));
1296 /* If we didn't find a process, one of two things presumably happened:
1297 - A process we started and then detached from has exited. Ignore it.
1298 - A process we are controlling has forked and the new child's stop
1299 was reported to us by the kernel. Save its PID. */
1300 if (child
== NULL
&& WIFSTOPPED (*wstatp
))
1302 add_to_pid_list (&stopped_pids
, ret
, *wstatp
);
1305 else if (child
== NULL
)
1310 child
->last_status
= *wstatp
;
1312 if (WIFSTOPPED (*wstatp
))
1314 struct process_info
*proc
;
1316 /* Architecture-specific setup after inferior is running. This
1317 needs to happen after we have attached to the inferior and it
1318 is stopped for the first time, but before we access any
1319 inferior registers. */
1320 proc
= find_process_pid (pid_of (child
));
1321 if (proc
->private->new_inferior
)
1323 struct thread_info
*saved_inferior
;
1325 saved_inferior
= current_inferior
;
1326 current_inferior
= get_lwp_thread (child
);
1328 the_low_target
.arch_setup ();
1330 current_inferior
= saved_inferior
;
1332 proc
->private->new_inferior
= 0;
1336 /* Fetch the possibly triggered data watchpoint info and store it in
1339 On some archs, like x86, that use debug registers to set
1340 watchpoints, it's possible that the way to know which watched
1341 address trapped, is to check the register that is used to select
1342 which address to watch. Problem is, between setting the
1343 watchpoint and reading back which data address trapped, the user
1344 may change the set of watchpoints, and, as a consequence, GDB
1345 changes the debug registers in the inferior. To avoid reading
1346 back a stale stopped-data-address when that happens, we cache in
1347 LP the fact that a watchpoint trapped, and the corresponding data
1348 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1349 changes the debug registers meanwhile, we have the cached data we
1352 if (WIFSTOPPED (*wstatp
) && WSTOPSIG (*wstatp
) == SIGTRAP
)
1354 if (the_low_target
.stopped_by_watchpoint
== NULL
)
1356 child
->stopped_by_watchpoint
= 0;
1360 struct thread_info
*saved_inferior
;
1362 saved_inferior
= current_inferior
;
1363 current_inferior
= get_lwp_thread (child
);
1365 child
->stopped_by_watchpoint
1366 = the_low_target
.stopped_by_watchpoint ();
1368 if (child
->stopped_by_watchpoint
)
1370 if (the_low_target
.stopped_data_address
!= NULL
)
1371 child
->stopped_data_address
1372 = the_low_target
.stopped_data_address ();
1374 child
->stopped_data_address
= 0;
1377 current_inferior
= saved_inferior
;
1381 /* Store the STOP_PC, with adjustment applied. This depends on the
1382 architecture being defined already (so that CHILD has a valid
1383 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1385 if (WIFSTOPPED (*wstatp
))
1386 child
->stop_pc
= get_stop_pc (child
);
1389 && WIFSTOPPED (*wstatp
)
1390 && the_low_target
.get_pc
!= NULL
)
1392 struct thread_info
*saved_inferior
= current_inferior
;
1393 struct regcache
*regcache
;
1396 current_inferior
= get_lwp_thread (child
);
1397 regcache
= get_thread_regcache (current_inferior
, 1);
1398 pc
= (*the_low_target
.get_pc
) (regcache
);
1399 debug_printf ("linux_wait_for_lwp: pc is 0x%lx\n", (long) pc
);
1400 current_inferior
= saved_inferior
;
1406 /* This function should only be called if the LWP got a SIGTRAP.
1408 Handle any tracepoint steps or hits. Return true if a tracepoint
1409 event was handled, 0 otherwise. */
1412 handle_tracepoints (struct lwp_info
*lwp
)
1414 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1415 int tpoint_related_event
= 0;
1417 /* If this tracepoint hit causes a tracing stop, we'll immediately
1418 uninsert tracepoints. To do this, we temporarily pause all
1419 threads, unpatch away, and then unpause threads. We need to make
1420 sure the unpausing doesn't resume LWP too. */
1423 /* And we need to be sure that any all-threads-stopping doesn't try
1424 to move threads out of the jump pads, as it could deadlock the
1425 inferior (LWP could be in the jump pad, maybe even holding the
1428 /* Do any necessary step collect actions. */
1429 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1431 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1433 /* See if we just hit a tracepoint and do its main collect
1435 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1439 gdb_assert (lwp
->suspended
== 0);
1440 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1442 if (tpoint_related_event
)
1445 debug_printf ("got a tracepoint event\n");
1452 /* Convenience wrapper. Returns true if LWP is presently collecting a
1456 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1457 struct fast_tpoint_collect_status
*status
)
1459 CORE_ADDR thread_area
;
1461 if (the_low_target
.get_thread_area
== NULL
)
1464 /* Get the thread area address. This is used to recognize which
1465 thread is which when tracing with the in-process agent library.
1466 We don't read anything from the address, and treat it as opaque;
1467 it's the address itself that we assume is unique per-thread. */
1468 if ((*the_low_target
.get_thread_area
) (lwpid_of (lwp
), &thread_area
) == -1)
1471 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1474 /* The reason we resume in the caller, is because we want to be able
1475 to pass lwp->status_pending as WSTAT, and we need to clear
1476 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1477 refuses to resume. */
1480 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1482 struct thread_info
*saved_inferior
;
1484 saved_inferior
= current_inferior
;
1485 current_inferior
= get_lwp_thread (lwp
);
1488 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1489 && supports_fast_tracepoints ()
1490 && agent_loaded_p ())
1492 struct fast_tpoint_collect_status status
;
1496 debug_printf ("Checking whether LWP %ld needs to move out of the "
1500 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1503 || (WSTOPSIG (*wstat
) != SIGILL
1504 && WSTOPSIG (*wstat
) != SIGFPE
1505 && WSTOPSIG (*wstat
) != SIGSEGV
1506 && WSTOPSIG (*wstat
) != SIGBUS
))
1508 lwp
->collecting_fast_tracepoint
= r
;
1512 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1514 /* Haven't executed the original instruction yet.
1515 Set breakpoint there, and wait till it's hit,
1516 then single-step until exiting the jump pad. */
1517 lwp
->exit_jump_pad_bkpt
1518 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1522 debug_printf ("Checking whether LWP %ld needs to move out of "
1523 "the jump pad...it does\n",
1525 current_inferior
= saved_inferior
;
1532 /* If we get a synchronous signal while collecting, *and*
1533 while executing the (relocated) original instruction,
1534 reset the PC to point at the tpoint address, before
1535 reporting to GDB. Otherwise, it's an IPA lib bug: just
1536 report the signal to GDB, and pray for the best. */
1538 lwp
->collecting_fast_tracepoint
= 0;
1541 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1542 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1545 struct regcache
*regcache
;
1547 /* The si_addr on a few signals references the address
1548 of the faulting instruction. Adjust that as
1550 if ((WSTOPSIG (*wstat
) == SIGILL
1551 || WSTOPSIG (*wstat
) == SIGFPE
1552 || WSTOPSIG (*wstat
) == SIGBUS
1553 || WSTOPSIG (*wstat
) == SIGSEGV
)
1554 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
),
1555 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
1556 /* Final check just to make sure we don't clobber
1557 the siginfo of non-kernel-sent signals. */
1558 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1560 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1561 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
),
1562 (PTRACE_TYPE_ARG3
) 0, &info
);
1565 regcache
= get_thread_regcache (get_lwp_thread (lwp
), 1);
1566 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1567 lwp
->stop_pc
= status
.tpoint_addr
;
1569 /* Cancel any fast tracepoint lock this thread was
1571 force_unlock_trace_buffer ();
1574 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1577 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
1578 "stopping all threads momentarily.\n");
1580 stop_all_lwps (1, lwp
);
1581 cancel_breakpoints ();
1583 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1584 lwp
->exit_jump_pad_bkpt
= NULL
;
1586 unstop_all_lwps (1, lwp
);
1588 gdb_assert (lwp
->suspended
>= 0);
1594 debug_printf ("Checking whether LWP %ld needs to move out of the "
1598 current_inferior
= saved_inferior
;
1602 /* Enqueue one signal in the "signals to report later when out of the
1606 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1608 struct pending_signals
*p_sig
;
1611 debug_printf ("Deferring signal %d for LWP %ld.\n",
1612 WSTOPSIG (*wstat
), lwpid_of (lwp
));
1616 struct pending_signals
*sig
;
1618 for (sig
= lwp
->pending_signals_to_report
;
1621 debug_printf (" Already queued %d\n",
1624 debug_printf (" (no more currently queued signals)\n");
1627 /* Don't enqueue non-RT signals if they are already in the deferred
1628 queue. (SIGSTOP being the easiest signal to see ending up here
1630 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1632 struct pending_signals
*sig
;
1634 for (sig
= lwp
->pending_signals_to_report
;
1638 if (sig
->signal
== WSTOPSIG (*wstat
))
1641 debug_printf ("Not requeuing already queued non-RT signal %d"
1650 p_sig
= xmalloc (sizeof (*p_sig
));
1651 p_sig
->prev
= lwp
->pending_signals_to_report
;
1652 p_sig
->signal
= WSTOPSIG (*wstat
);
1653 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1654 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
1657 lwp
->pending_signals_to_report
= p_sig
;
1660 /* Dequeue one signal from the "signals to report later when out of
1661 the jump pad" list. */
1664 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1666 if (lwp
->pending_signals_to_report
!= NULL
)
1668 struct pending_signals
**p_sig
;
1670 p_sig
= &lwp
->pending_signals_to_report
;
1671 while ((*p_sig
)->prev
!= NULL
)
1672 p_sig
= &(*p_sig
)->prev
;
1674 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1675 if ((*p_sig
)->info
.si_signo
!= 0)
1676 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
1682 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
1683 WSTOPSIG (*wstat
), lwpid_of (lwp
));
1687 struct pending_signals
*sig
;
1689 for (sig
= lwp
->pending_signals_to_report
;
1692 debug_printf (" Still queued %d\n",
1695 debug_printf (" (no more queued signals)\n");
1704 /* Arrange for a breakpoint to be hit again later. We don't keep the
1705 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1706 will handle the current event, eventually we will resume this LWP,
1707 and this breakpoint will trap again. */
1710 cancel_breakpoint (struct lwp_info
*lwp
)
1712 struct thread_info
*saved_inferior
;
1714 /* There's nothing to do if we don't support breakpoints. */
1715 if (!supports_breakpoints ())
1718 /* breakpoint_at reads from current inferior. */
1719 saved_inferior
= current_inferior
;
1720 current_inferior
= get_lwp_thread (lwp
);
1722 if ((*the_low_target
.breakpoint_at
) (lwp
->stop_pc
))
1725 debug_printf ("CB: Push back breakpoint for %s\n",
1726 target_pid_to_str (ptid_of (lwp
)));
1728 /* Back up the PC if necessary. */
1729 if (the_low_target
.decr_pc_after_break
)
1731 struct regcache
*regcache
1732 = get_thread_regcache (current_inferior
, 1);
1733 (*the_low_target
.set_pc
) (regcache
, lwp
->stop_pc
);
1736 current_inferior
= saved_inferior
;
1742 debug_printf ("CB: No breakpoint found at %s for [%s]\n",
1743 paddress (lwp
->stop_pc
),
1744 target_pid_to_str (ptid_of (lwp
)));
1747 current_inferior
= saved_inferior
;
1751 /* When the event-loop is doing a step-over, this points at the thread
1753 ptid_t step_over_bkpt
;
1755 /* Wait for an event from child PID. If PID is -1, wait for any
1756 child. Store the stop status through the status pointer WSTAT.
1757 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1758 event was found and OPTIONS contains WNOHANG. Return the PID of
1759 the stopped child otherwise. */
1762 linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
)
1764 struct lwp_info
*event_child
, *requested_child
;
1768 requested_child
= NULL
;
1770 /* Check for a lwp with a pending status. */
1772 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
1774 event_child
= (struct lwp_info
*)
1775 find_inferior (&all_lwps
, status_pending_p_callback
, &ptid
);
1776 if (debug_threads
&& event_child
)
1777 debug_printf ("Got a pending child %ld\n", lwpid_of (event_child
));
1781 requested_child
= find_lwp_pid (ptid
);
1783 if (stopping_threads
== NOT_STOPPING_THREADS
1784 && requested_child
->status_pending_p
1785 && requested_child
->collecting_fast_tracepoint
)
1787 enqueue_one_deferred_signal (requested_child
,
1788 &requested_child
->status_pending
);
1789 requested_child
->status_pending_p
= 0;
1790 requested_child
->status_pending
= 0;
1791 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
1794 if (requested_child
->suspended
1795 && requested_child
->status_pending_p
)
1796 fatal ("requesting an event out of a suspended child?");
1798 if (requested_child
->status_pending_p
)
1799 event_child
= requested_child
;
1802 if (event_child
!= NULL
)
1805 debug_printf ("Got an event from pending child %ld (%04x)\n",
1806 lwpid_of (event_child
), event_child
->status_pending
);
1807 *wstat
= event_child
->status_pending
;
1808 event_child
->status_pending_p
= 0;
1809 event_child
->status_pending
= 0;
1810 current_inferior
= get_lwp_thread (event_child
);
1811 return lwpid_of (event_child
);
1814 if (ptid_is_pid (ptid
))
1816 /* A request to wait for a specific tgid. This is not possible
1817 with waitpid, so instead, we wait for any child, and leave
1818 children we're not interested in right now with a pending
1819 status to report later. */
1820 wait_ptid
= minus_one_ptid
;
1825 /* We only enter this loop if no process has a pending wait status. Thus
1826 any action taken in response to a wait status inside this loop is
1827 responding as soon as we detect the status, not after any pending
1831 event_child
= linux_wait_for_lwp (wait_ptid
, wstat
, options
);
1833 if ((options
& WNOHANG
) && event_child
== NULL
)
1836 debug_printf ("WNOHANG set, no event found\n");
1840 if (event_child
== NULL
)
1841 error ("event from unknown child");
1843 if (ptid_is_pid (ptid
)
1844 && ptid_get_pid (ptid
) != ptid_get_pid (ptid_of (event_child
)))
1846 if (! WIFSTOPPED (*wstat
))
1847 mark_lwp_dead (event_child
, *wstat
);
1850 event_child
->status_pending_p
= 1;
1851 event_child
->status_pending
= *wstat
;
1856 current_inferior
= get_lwp_thread (event_child
);
1858 /* Check for thread exit. */
1859 if (! WIFSTOPPED (*wstat
))
1862 debug_printf ("LWP %ld exiting\n", lwpid_of (event_child
));
1864 /* If the last thread is exiting, just return. */
1865 if (last_thread_of_process_p (current_inferior
))
1868 debug_printf ("LWP %ld is last lwp of process\n",
1869 lwpid_of (event_child
));
1870 return lwpid_of (event_child
);
1875 current_inferior
= (struct thread_info
*) all_threads
.head
;
1877 debug_printf ("Current inferior is now %ld\n",
1878 lwpid_of (get_thread_lwp (current_inferior
)));
1882 current_inferior
= NULL
;
1884 debug_printf ("Current inferior is now <NULL>\n");
1887 /* If we were waiting for this particular child to do something...
1888 well, it did something. */
1889 if (requested_child
!= NULL
)
1891 int lwpid
= lwpid_of (event_child
);
1893 /* Cancel the step-over operation --- the thread that
1894 started it is gone. */
1895 if (finish_step_over (event_child
))
1896 unstop_all_lwps (1, event_child
);
1897 delete_lwp (event_child
);
1901 delete_lwp (event_child
);
1903 /* Wait for a more interesting event. */
1907 if (event_child
->must_set_ptrace_flags
)
1909 linux_enable_event_reporting (lwpid_of (event_child
));
1910 event_child
->must_set_ptrace_flags
= 0;
1913 if (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) == SIGTRAP
1914 && *wstat
>> 16 != 0)
1916 handle_extended_wait (event_child
, *wstat
);
1920 if (WIFSTOPPED (*wstat
)
1921 && WSTOPSIG (*wstat
) == SIGSTOP
1922 && event_child
->stop_expected
)
1927 debug_printf ("Expected stop.\n");
1928 event_child
->stop_expected
= 0;
1930 should_stop
= (current_inferior
->last_resume_kind
== resume_stop
1931 || stopping_threads
!= NOT_STOPPING_THREADS
);
1935 linux_resume_one_lwp (event_child
,
1936 event_child
->stepping
, 0, NULL
);
1941 return lwpid_of (event_child
);
1948 /* Count the LWP's that have had events. */
1951 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
1953 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1954 struct thread_info
*thread
= get_lwp_thread (lp
);
1957 gdb_assert (count
!= NULL
);
1959 /* Count only resumed LWPs that have a SIGTRAP event pending that
1960 should be reported to GDB. */
1961 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1962 && thread
->last_resume_kind
!= resume_stop
1963 && lp
->status_pending_p
1964 && WIFSTOPPED (lp
->status_pending
)
1965 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
1966 && !breakpoint_inserted_here (lp
->stop_pc
))
1972 /* Select the LWP (if any) that is currently being single-stepped. */
1975 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1977 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1978 struct thread_info
*thread
= get_lwp_thread (lp
);
1980 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
1981 && thread
->last_resume_kind
== resume_step
1982 && lp
->status_pending_p
)
1988 /* Select the Nth LWP that has had a SIGTRAP event that should be
1992 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
1994 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
1995 struct thread_info
*thread
= get_lwp_thread (lp
);
1996 int *selector
= data
;
1998 gdb_assert (selector
!= NULL
);
2000 /* Select only resumed LWPs that have a SIGTRAP event pending. */
2001 if (thread
->last_resume_kind
!= resume_stop
2002 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2003 && lp
->status_pending_p
2004 && WIFSTOPPED (lp
->status_pending
)
2005 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2006 && !breakpoint_inserted_here (lp
->stop_pc
))
2007 if ((*selector
)-- == 0)
2014 cancel_breakpoints_callback (struct inferior_list_entry
*entry
, void *data
)
2016 struct lwp_info
*lp
= (struct lwp_info
*) entry
;
2017 struct thread_info
*thread
= get_lwp_thread (lp
);
2018 struct lwp_info
*event_lp
= data
;
2020 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
2024 /* If a LWP other than the LWP that we're reporting an event for has
2025 hit a GDB breakpoint (as opposed to some random trap signal),
2026 then just arrange for it to hit it again later. We don't keep
2027 the SIGTRAP status and don't forward the SIGTRAP signal to the
2028 LWP. We will handle the current event, eventually we will resume
2029 all LWPs, and this one will get its breakpoint trap again.
2031 If we do not do this, then we run the risk that the user will
2032 delete or disable the breakpoint, but the LWP will have already
2035 if (thread
->last_resume_kind
!= resume_stop
2036 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2037 && lp
->status_pending_p
2038 && WIFSTOPPED (lp
->status_pending
)
2039 && WSTOPSIG (lp
->status_pending
) == SIGTRAP
2041 && !lp
->stopped_by_watchpoint
2042 && cancel_breakpoint (lp
))
2043 /* Throw away the SIGTRAP. */
2044 lp
->status_pending_p
= 0;
2050 linux_cancel_breakpoints (void)
2052 find_inferior (&all_lwps
, cancel_breakpoints_callback
, NULL
);
2055 /* Select one LWP out of those that have events pending. */
2058 select_event_lwp (struct lwp_info
**orig_lp
)
2061 int random_selector
;
2062 struct lwp_info
*event_lp
;
2064 /* Give preference to any LWP that is being single-stepped. */
2066 = (struct lwp_info
*) find_inferior (&all_lwps
,
2067 select_singlestep_lwp_callback
, NULL
);
2068 if (event_lp
!= NULL
)
2071 debug_printf ("SEL: Select single-step %s\n",
2072 target_pid_to_str (ptid_of (event_lp
)));
2076 /* No single-stepping LWP. Select one at random, out of those
2077 which have had SIGTRAP events. */
2079 /* First see how many SIGTRAP events we have. */
2080 find_inferior (&all_lwps
, count_events_callback
, &num_events
);
2082 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
2083 random_selector
= (int)
2084 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2086 if (debug_threads
&& num_events
> 1)
2087 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2088 num_events
, random_selector
);
2090 event_lp
= (struct lwp_info
*) find_inferior (&all_lwps
,
2091 select_event_lwp_callback
,
2095 if (event_lp
!= NULL
)
2097 /* Switch the event LWP. */
2098 *orig_lp
= event_lp
;
2102 /* Decrement the suspend count of an LWP. */
2105 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2107 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2109 /* Ignore EXCEPT. */
2115 gdb_assert (lwp
->suspended
>= 0);
2119 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2123 unsuspend_all_lwps (struct lwp_info
*except
)
2125 find_inferior (&all_lwps
, unsuspend_one_lwp
, except
);
2128 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2129 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2131 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2132 static ptid_t
linux_wait_1 (ptid_t ptid
,
2133 struct target_waitstatus
*ourstatus
,
2134 int target_options
);
2136 /* Stabilize threads (move out of jump pads).
2138 If a thread is midway collecting a fast tracepoint, we need to
2139 finish the collection and move it out of the jump pad before
2140 reporting the signal.
2142 This avoids recursion while collecting (when a signal arrives
2143 midway, and the signal handler itself collects), which would trash
2144 the trace buffer. In case the user set a breakpoint in a signal
2145 handler, this avoids the backtrace showing the jump pad, etc..
2146 Most importantly, there are certain things we can't do safely if
2147 threads are stopped in a jump pad (or in its callee's). For
2150 - starting a new trace run. A thread still collecting the
2151 previous run, could trash the trace buffer when resumed. The trace
2152 buffer control structures would have been reset but the thread had
2153 no way to tell. The thread could even midway memcpy'ing to the
2154 buffer, which would mean that when resumed, it would clobber the
2155 trace buffer that had been set for a new run.
2157 - we can't rewrite/reuse the jump pads for new tracepoints
2158 safely. Say you do tstart while a thread is stopped midway while
2159 collecting. When the thread is later resumed, it finishes the
2160 collection, and returns to the jump pad, to execute the original
2161 instruction that was under the tracepoint jump at the time the
2162 older run had been started. If the jump pad had been rewritten
2163 since for something else in the new run, the thread would now
2164 execute the wrong / random instructions. */
2167 linux_stabilize_threads (void)
2169 struct thread_info
*save_inferior
;
2170 struct lwp_info
*lwp_stuck
;
2173 = (struct lwp_info
*) find_inferior (&all_lwps
,
2174 stuck_in_jump_pad_callback
, NULL
);
2175 if (lwp_stuck
!= NULL
)
2178 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2179 lwpid_of (lwp_stuck
));
2183 save_inferior
= current_inferior
;
2185 stabilizing_threads
= 1;
2188 for_each_inferior (&all_lwps
, move_out_of_jump_pad_callback
);
2190 /* Loop until all are stopped out of the jump pads. */
2191 while (find_inferior (&all_lwps
, lwp_running
, NULL
) != NULL
)
2193 struct target_waitstatus ourstatus
;
2194 struct lwp_info
*lwp
;
2197 /* Note that we go through the full wait even loop. While
2198 moving threads out of jump pad, we need to be able to step
2199 over internal breakpoints and such. */
2200 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2202 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2204 lwp
= get_thread_lwp (current_inferior
);
2209 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2210 || current_inferior
->last_resume_kind
== resume_stop
)
2212 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2213 enqueue_one_deferred_signal (lwp
, &wstat
);
2218 find_inferior (&all_lwps
, unsuspend_one_lwp
, NULL
);
2220 stabilizing_threads
= 0;
2222 current_inferior
= save_inferior
;
2227 = (struct lwp_info
*) find_inferior (&all_lwps
,
2228 stuck_in_jump_pad_callback
, NULL
);
2229 if (lwp_stuck
!= NULL
)
2230 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2231 lwpid_of (lwp_stuck
));
2235 /* Wait for process, returns status. */
2238 linux_wait_1 (ptid_t ptid
,
2239 struct target_waitstatus
*ourstatus
, int target_options
)
2242 struct lwp_info
*event_child
;
2245 int step_over_finished
;
2246 int bp_explains_trap
;
2247 int maybe_internal_trap
;
2255 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
2258 /* Translate generic target options into linux options. */
2260 if (target_options
& TARGET_WNOHANG
)
2264 bp_explains_trap
= 0;
2267 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2269 /* If we were only supposed to resume one thread, only wait for
2270 that thread - if it's still alive. If it died, however - which
2271 can happen if we're coming from the thread death case below -
2272 then we need to make sure we restart the other threads. We could
2273 pick a thread at random or restart all; restarting all is less
2276 && !ptid_equal (cont_thread
, null_ptid
)
2277 && !ptid_equal (cont_thread
, minus_one_ptid
))
2279 struct thread_info
*thread
;
2281 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
2284 /* No stepping, no signal - unless one is pending already, of course. */
2287 struct thread_resume resume_info
;
2288 resume_info
.thread
= minus_one_ptid
;
2289 resume_info
.kind
= resume_continue
;
2290 resume_info
.sig
= 0;
2291 linux_resume (&resume_info
, 1);
2297 if (ptid_equal (step_over_bkpt
, null_ptid
))
2298 pid
= linux_wait_for_event (ptid
, &w
, options
);
2302 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
2303 target_pid_to_str (step_over_bkpt
));
2304 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2307 if (pid
== 0) /* only if TARGET_WNOHANG */
2311 debug_printf ("linux_wait_1 ret = null_ptid\n");
2317 event_child
= get_thread_lwp (current_inferior
);
2319 /* If we are waiting for a particular child, and it exited,
2320 linux_wait_for_event will return its exit status. Similarly if
2321 the last child exited. If this is not the last child, however,
2322 do not report it as exited until there is a 'thread exited' response
2323 available in the remote protocol. Instead, just wait for another event.
2324 This should be safe, because if the thread crashed we will already
2325 have reported the termination signal to GDB; that should stop any
2326 in-progress stepping operations, etc.
2328 Report the exit status of the last thread to exit. This matches
2329 LinuxThreads' behavior. */
2331 if (last_thread_of_process_p (current_inferior
))
2333 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2337 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2338 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2342 debug_printf ("linux_wait_1 ret = %s, exited with "
2344 target_pid_to_str (ptid_of (event_child
)),
2351 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2352 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
2356 debug_printf ("linux_wait_1 ret = %s, terminated with "
2358 target_pid_to_str (ptid_of (event_child
)),
2364 return ptid_of (event_child
);
2369 if (!WIFSTOPPED (w
))
2373 /* If this event was not handled before, and is not a SIGTRAP, we
2374 report it. SIGILL and SIGSEGV are also treated as traps in case
2375 a breakpoint is inserted at the current PC. If this target does
2376 not support internal breakpoints at all, we also report the
2377 SIGTRAP without further processing; it's of no concern to us. */
2379 = (supports_breakpoints ()
2380 && (WSTOPSIG (w
) == SIGTRAP
2381 || ((WSTOPSIG (w
) == SIGILL
2382 || WSTOPSIG (w
) == SIGSEGV
)
2383 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2385 if (maybe_internal_trap
)
2387 /* Handle anything that requires bookkeeping before deciding to
2388 report the event or continue waiting. */
2390 /* First check if we can explain the SIGTRAP with an internal
2391 breakpoint, or if we should possibly report the event to GDB.
2392 Do this before anything that may remove or insert a
2394 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2396 /* We have a SIGTRAP, possibly a step-over dance has just
2397 finished. If so, tweak the state machine accordingly,
2398 reinsert breakpoints and delete any reinsert (software
2399 single-step) breakpoints. */
2400 step_over_finished
= finish_step_over (event_child
);
2402 /* Now invoke the callbacks of any internal breakpoints there. */
2403 check_breakpoints (event_child
->stop_pc
);
2405 /* Handle tracepoint data collecting. This may overflow the
2406 trace buffer, and cause a tracing stop, removing
2408 trace_event
= handle_tracepoints (event_child
);
2410 if (bp_explains_trap
)
2412 /* If we stepped or ran into an internal breakpoint, we've
2413 already handled it. So next time we resume (from this
2414 PC), we should step over it. */
2416 debug_printf ("Hit a gdbserver breakpoint.\n");
2418 if (breakpoint_here (event_child
->stop_pc
))
2419 event_child
->need_step_over
= 1;
2424 /* We have some other signal, possibly a step-over dance was in
2425 progress, and it should be cancelled too. */
2426 step_over_finished
= finish_step_over (event_child
);
2429 /* We have all the data we need. Either report the event to GDB, or
2430 resume threads and keep waiting for more. */
2432 /* If we're collecting a fast tracepoint, finish the collection and
2433 move out of the jump pad before delivering a signal. See
2434 linux_stabilize_threads. */
2437 && WSTOPSIG (w
) != SIGTRAP
2438 && supports_fast_tracepoints ()
2439 && agent_loaded_p ())
2442 debug_printf ("Got signal %d for LWP %ld. Check if we need "
2443 "to defer or adjust it.\n",
2444 WSTOPSIG (w
), lwpid_of (event_child
));
2446 /* Allow debugging the jump pad itself. */
2447 if (current_inferior
->last_resume_kind
!= resume_step
2448 && maybe_move_out_of_jump_pad (event_child
, &w
))
2450 enqueue_one_deferred_signal (event_child
, &w
);
2453 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
2454 WSTOPSIG (w
), lwpid_of (event_child
));
2456 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2461 if (event_child
->collecting_fast_tracepoint
)
2464 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
2465 "Check if we're already there.\n",
2466 lwpid_of (event_child
),
2467 event_child
->collecting_fast_tracepoint
);
2471 event_child
->collecting_fast_tracepoint
2472 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2474 if (event_child
->collecting_fast_tracepoint
!= 1)
2476 /* No longer need this breakpoint. */
2477 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2480 debug_printf ("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)
2505 debug_printf ("fast tracepoint finished "
2506 "collecting successfully.\n");
2508 /* We may have a deferred signal to report. */
2509 if (dequeue_one_deferred_signal (event_child
, &w
))
2512 debug_printf ("dequeued one signal.\n");
2517 debug_printf ("no deferred signals.\n");
2519 if (stabilizing_threads
)
2521 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2522 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
2526 debug_printf ("linux_wait_1 ret = %s, stopped "
2527 "while stabilizing threads\n",
2528 target_pid_to_str (ptid_of (event_child
)));
2532 return ptid_of (event_child
);
2538 /* Check whether GDB would be interested in this event. */
2540 /* If GDB is not interested in this signal, don't stop other
2541 threads, and don't report it to GDB. Just resume the inferior
2542 right away. We do this for threading-related signals as well as
2543 any that GDB specifically requested we ignore. But never ignore
2544 SIGSTOP if we sent it ourselves, and do not ignore signals when
2545 stepping - they may require special handling to skip the signal
2547 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2550 && current_inferior
->last_resume_kind
!= resume_step
2552 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2553 (current_process ()->private->thread_db
!= NULL
2554 && (WSTOPSIG (w
) == __SIGRTMIN
2555 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2558 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
2559 && !(WSTOPSIG (w
) == SIGSTOP
2560 && current_inferior
->last_resume_kind
== resume_stop
))))
2562 siginfo_t info
, *info_p
;
2565 debug_printf ("Ignored signal %d for LWP %ld.\n",
2566 WSTOPSIG (w
), lwpid_of (event_child
));
2568 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (event_child
),
2569 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
2573 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2574 WSTOPSIG (w
), info_p
);
2578 /* Note that all addresses are always "out of the step range" when
2579 there's no range to begin with. */
2580 in_step_range
= lwp_in_step_range (event_child
);
2582 /* If GDB wanted this thread to single step, and the thread is out
2583 of the step range, we always want to report the SIGTRAP, and let
2584 GDB handle it. Watchpoints should always be reported. So should
2585 signals we can't explain. A SIGTRAP we can't explain could be a
2586 GDB breakpoint --- we may or not support Z0 breakpoints. If we
2587 do, we're be able to handle GDB breakpoints on top of internal
2588 breakpoints, by handling the internal breakpoint and still
2589 reporting the event to GDB. If we don't, we're out of luck, GDB
2590 won't see the breakpoint hit. */
2591 report_to_gdb
= (!maybe_internal_trap
2592 || (current_inferior
->last_resume_kind
== resume_step
2594 || event_child
->stopped_by_watchpoint
2595 || (!step_over_finished
&& !in_step_range
2596 && !bp_explains_trap
&& !trace_event
)
2597 || (gdb_breakpoint_here (event_child
->stop_pc
)
2598 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
2599 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
)));
2601 run_breakpoint_commands (event_child
->stop_pc
);
2603 /* We found no reason GDB would want us to stop. We either hit one
2604 of our own breakpoints, or finished an internal step GDB
2605 shouldn't know about. */
2610 if (bp_explains_trap
)
2611 debug_printf ("Hit a gdbserver breakpoint.\n");
2612 if (step_over_finished
)
2613 debug_printf ("Step-over finished.\n");
2615 debug_printf ("Tracepoint event.\n");
2616 if (lwp_in_step_range (event_child
))
2617 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
2618 paddress (event_child
->stop_pc
),
2619 paddress (event_child
->step_range_start
),
2620 paddress (event_child
->step_range_end
));
2623 /* We're not reporting this breakpoint to GDB, so apply the
2624 decr_pc_after_break adjustment to the inferior's regcache
2627 if (the_low_target
.set_pc
!= NULL
)
2629 struct regcache
*regcache
2630 = get_thread_regcache (get_lwp_thread (event_child
), 1);
2631 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2634 /* We may have finished stepping over a breakpoint. If so,
2635 we've stopped and suspended all LWPs momentarily except the
2636 stepping one. This is where we resume them all again. We're
2637 going to keep waiting, so use proceed, which handles stepping
2638 over the next breakpoint. */
2640 debug_printf ("proceeding all threads.\n");
2642 if (step_over_finished
)
2643 unsuspend_all_lwps (event_child
);
2645 proceed_all_lwps ();
2651 if (current_inferior
->last_resume_kind
== resume_step
)
2653 if (event_child
->step_range_start
== event_child
->step_range_end
)
2654 debug_printf ("GDB wanted to single-step, reporting event.\n");
2655 else if (!lwp_in_step_range (event_child
))
2656 debug_printf ("Out of step range, reporting event.\n");
2658 if (event_child
->stopped_by_watchpoint
)
2659 debug_printf ("Stopped by watchpoint.\n");
2660 if (gdb_breakpoint_here (event_child
->stop_pc
))
2661 debug_printf ("Stopped by GDB breakpoint.\n");
2663 debug_printf ("Hit a non-gdbserver trap event.\n");
2666 /* Alright, we're going to report a stop. */
2668 if (!non_stop
&& !stabilizing_threads
)
2670 /* In all-stop, stop all threads. */
2671 stop_all_lwps (0, NULL
);
2673 /* If we're not waiting for a specific LWP, choose an event LWP
2674 from among those that have had events. Giving equal priority
2675 to all LWPs that have had events helps prevent
2677 if (ptid_equal (ptid
, minus_one_ptid
))
2679 event_child
->status_pending_p
= 1;
2680 event_child
->status_pending
= w
;
2682 select_event_lwp (&event_child
);
2684 event_child
->status_pending_p
= 0;
2685 w
= event_child
->status_pending
;
2688 /* Now that we've selected our final event LWP, cancel any
2689 breakpoints in other LWPs that have hit a GDB breakpoint.
2690 See the comment in cancel_breakpoints_callback to find out
2692 find_inferior (&all_lwps
, cancel_breakpoints_callback
, event_child
);
2694 /* If we were going a step-over, all other threads but the stepping one
2695 had been paused in start_step_over, with their suspend counts
2696 incremented. We don't want to do a full unstop/unpause, because we're
2697 in all-stop mode (so we want threads stopped), but we still need to
2698 unsuspend the other threads, to decrement their `suspended' count
2700 if (step_over_finished
)
2701 unsuspend_all_lwps (event_child
);
2703 /* Stabilize threads (move out of jump pads). */
2704 stabilize_threads ();
2708 /* If we just finished a step-over, then all threads had been
2709 momentarily paused. In all-stop, that's fine, we want
2710 threads stopped by now anyway. In non-stop, we need to
2711 re-resume threads that GDB wanted to be running. */
2712 if (step_over_finished
)
2713 unstop_all_lwps (1, event_child
);
2716 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2718 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 and it stopped cleanly, so report as SIG0. The use of
2723 SIGSTOP is an implementation detail. */
2724 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
2726 else if (current_inferior
->last_resume_kind
== resume_stop
2727 && WSTOPSIG (w
) != SIGSTOP
)
2729 /* A thread that has been requested to stop by GDB with vCont;t,
2730 but, it stopped for other reasons. */
2731 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
2735 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
2738 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
2742 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
2743 target_pid_to_str (ptid_of (event_child
)),
2744 ourstatus
->kind
, ourstatus
->value
.sig
);
2748 return ptid_of (event_child
);
2751 /* Get rid of any pending event in the pipe. */
2753 async_file_flush (void)
2759 ret
= read (linux_event_pipe
[0], &buf
, 1);
2760 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
2763 /* Put something in the pipe, so the event loop wakes up. */
2765 async_file_mark (void)
2769 async_file_flush ();
2772 ret
= write (linux_event_pipe
[1], "+", 1);
2773 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
2775 /* Ignore EAGAIN. If the pipe is full, the event loop will already
2776 be awakened anyway. */
2780 linux_wait (ptid_t ptid
,
2781 struct target_waitstatus
*ourstatus
, int target_options
)
2785 /* Flush the async file first. */
2786 if (target_is_async_p ())
2787 async_file_flush ();
2789 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
2791 /* If at least one stop was reported, there may be more. A single
2792 SIGCHLD can signal more than one child stop. */
2793 if (target_is_async_p ()
2794 && (target_options
& TARGET_WNOHANG
) != 0
2795 && !ptid_equal (event_ptid
, null_ptid
))
2801 /* Send a signal to an LWP. */
2804 kill_lwp (unsigned long lwpid
, int signo
)
2806 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2807 fails, then we are not using nptl threads and we should be using kill. */
2811 static int tkill_failed
;
2818 ret
= syscall (__NR_tkill
, lwpid
, signo
);
2819 if (errno
!= ENOSYS
)
2826 return kill (lwpid
, signo
);
2830 linux_stop_lwp (struct lwp_info
*lwp
)
2836 send_sigstop (struct lwp_info
*lwp
)
2840 pid
= lwpid_of (lwp
);
2842 /* If we already have a pending stop signal for this process, don't
2844 if (lwp
->stop_expected
)
2847 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
2853 debug_printf ("Sending sigstop to lwp %d\n", pid
);
2855 lwp
->stop_expected
= 1;
2856 kill_lwp (pid
, SIGSTOP
);
2860 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
2862 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2864 /* Ignore EXCEPT. */
2875 /* Increment the suspend count of an LWP, and stop it, if not stopped
2878 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
2881 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2883 /* Ignore EXCEPT. */
2889 return send_sigstop_callback (entry
, except
);
2893 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
2895 /* It's dead, really. */
2898 /* Store the exit status for later. */
2899 lwp
->status_pending_p
= 1;
2900 lwp
->status_pending
= wstat
;
2902 /* Prevent trying to stop it. */
2905 /* No further stops are expected from a dead lwp. */
2906 lwp
->stop_expected
= 0;
2910 wait_for_sigstop (struct inferior_list_entry
*entry
)
2912 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
2913 struct thread_info
*saved_inferior
;
2922 debug_printf ("wait_for_sigstop: LWP %ld already stopped\n",
2927 saved_inferior
= current_inferior
;
2928 if (saved_inferior
!= NULL
)
2929 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
2931 saved_tid
= null_ptid
; /* avoid bogus unused warning */
2933 ptid
= lwp
->head
.id
;
2936 debug_printf ("wait_for_sigstop: pulling one event\n");
2938 pid
= linux_wait_for_event (ptid
, &wstat
, __WALL
);
2940 /* If we stopped with a non-SIGSTOP signal, save it for later
2941 and record the pending SIGSTOP. If the process exited, just
2943 if (WIFSTOPPED (wstat
))
2946 debug_printf ("LWP %ld stopped with signal %d\n",
2947 lwpid_of (lwp
), WSTOPSIG (wstat
));
2949 if (WSTOPSIG (wstat
) != SIGSTOP
)
2952 debug_printf ("LWP %ld stopped with non-sigstop status %06x\n",
2953 lwpid_of (lwp
), wstat
);
2955 lwp
->status_pending_p
= 1;
2956 lwp
->status_pending
= wstat
;
2962 debug_printf ("Process %d exited while stopping LWPs\n", pid
);
2964 lwp
= find_lwp_pid (pid_to_ptid (pid
));
2967 /* Leave this status pending for the next time we're able to
2968 report it. In the mean time, we'll report this lwp as
2969 dead to GDB, so GDB doesn't try to read registers and
2970 memory from it. This can only happen if this was the
2971 last thread of the process; otherwise, PID is removed
2972 from the thread tables before linux_wait_for_event
2974 mark_lwp_dead (lwp
, wstat
);
2978 if (saved_inferior
== NULL
|| linux_thread_alive (saved_tid
))
2979 current_inferior
= saved_inferior
;
2983 debug_printf ("Previously current thread died.\n");
2987 /* We can't change the current inferior behind GDB's back,
2988 otherwise, a subsequent command may apply to the wrong
2990 current_inferior
= NULL
;
2994 /* Set a valid thread as current. */
2995 set_desired_inferior (0);
3000 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3001 move it out, because we need to report the stop event to GDB. For
3002 example, if the user puts a breakpoint in the jump pad, it's
3003 because she wants to debug it. */
3006 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3008 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3009 struct thread_info
*thread
= get_lwp_thread (lwp
);
3011 gdb_assert (lwp
->suspended
== 0);
3012 gdb_assert (lwp
->stopped
);
3014 /* Allow debugging the jump pad, gdb_collect, etc.. */
3015 return (supports_fast_tracepoints ()
3016 && agent_loaded_p ()
3017 && (gdb_breakpoint_here (lwp
->stop_pc
)
3018 || lwp
->stopped_by_watchpoint
3019 || thread
->last_resume_kind
== resume_step
)
3020 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3024 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3026 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3027 struct thread_info
*thread
= get_lwp_thread (lwp
);
3030 gdb_assert (lwp
->suspended
== 0);
3031 gdb_assert (lwp
->stopped
);
3033 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3035 /* Allow debugging the jump pad, gdb_collect, etc. */
3036 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3037 && !lwp
->stopped_by_watchpoint
3038 && thread
->last_resume_kind
!= resume_step
3039 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3042 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3047 lwp
->status_pending_p
= 0;
3048 enqueue_one_deferred_signal (lwp
, wstat
);
3051 debug_printf ("Signal %d for LWP %ld deferred "
3053 WSTOPSIG (*wstat
), lwpid_of (lwp
));
3056 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3063 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3065 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3074 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3075 If SUSPEND, then also increase the suspend count of every LWP,
3079 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3081 /* Should not be called recursively. */
3082 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3087 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3088 suspend
? "stop-and-suspend" : "stop",
3090 ? target_pid_to_str (ptid_of (except
))
3094 stopping_threads
= (suspend
3095 ? STOPPING_AND_SUSPENDING_THREADS
3096 : STOPPING_THREADS
);
3099 find_inferior (&all_lwps
, suspend_and_send_sigstop_callback
, except
);
3101 find_inferior (&all_lwps
, send_sigstop_callback
, except
);
3102 for_each_inferior (&all_lwps
, wait_for_sigstop
);
3103 stopping_threads
= NOT_STOPPING_THREADS
;
3107 debug_printf ("stop_all_lwps done, setting stopping_threads "
3108 "back to !stopping\n");
3113 /* Resume execution of the inferior process.
3114 If STEP is nonzero, single-step it.
3115 If SIGNAL is nonzero, give it that signal. */
3118 linux_resume_one_lwp (struct lwp_info
*lwp
,
3119 int step
, int signal
, siginfo_t
*info
)
3121 struct thread_info
*saved_inferior
;
3122 int fast_tp_collecting
;
3124 if (lwp
->stopped
== 0)
3127 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3129 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3131 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3132 user used the "jump" command, or "set $pc = foo"). */
3133 if (lwp
->stop_pc
!= get_pc (lwp
))
3135 /* Collecting 'while-stepping' actions doesn't make sense
3137 release_while_stepping_state_list (get_lwp_thread (lwp
));
3140 /* If we have pending signals or status, and a new signal, enqueue the
3141 signal. Also enqueue the signal if we are waiting to reinsert a
3142 breakpoint; it will be picked up again below. */
3144 && (lwp
->status_pending_p
3145 || lwp
->pending_signals
!= NULL
3146 || lwp
->bp_reinsert
!= 0
3147 || fast_tp_collecting
))
3149 struct pending_signals
*p_sig
;
3150 p_sig
= xmalloc (sizeof (*p_sig
));
3151 p_sig
->prev
= lwp
->pending_signals
;
3152 p_sig
->signal
= signal
;
3154 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3156 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3157 lwp
->pending_signals
= p_sig
;
3160 if (lwp
->status_pending_p
)
3163 debug_printf ("Not resuming lwp %ld (%s, signal %d, stop %s);"
3164 " has pending status\n",
3165 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3166 lwp
->stop_expected
? "expected" : "not expected");
3170 saved_inferior
= current_inferior
;
3171 current_inferior
= get_lwp_thread (lwp
);
3174 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
3175 lwpid_of (lwp
), step
? "step" : "continue", signal
,
3176 lwp
->stop_expected
? "expected" : "not expected");
3178 /* This bit needs some thinking about. If we get a signal that
3179 we must report while a single-step reinsert is still pending,
3180 we often end up resuming the thread. It might be better to
3181 (ew) allow a stack of pending events; then we could be sure that
3182 the reinsert happened right away and not lose any signals.
3184 Making this stack would also shrink the window in which breakpoints are
3185 uninserted (see comment in linux_wait_for_lwp) but not enough for
3186 complete correctness, so it won't solve that problem. It may be
3187 worthwhile just to solve this one, however. */
3188 if (lwp
->bp_reinsert
!= 0)
3191 debug_printf (" pending reinsert at 0x%s\n",
3192 paddress (lwp
->bp_reinsert
));
3194 if (can_hardware_single_step ())
3196 if (fast_tp_collecting
== 0)
3199 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
3201 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
3208 /* Postpone any pending signal. It was enqueued above. */
3212 if (fast_tp_collecting
== 1)
3215 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3216 " (exit-jump-pad-bkpt)\n",
3219 /* Postpone any pending signal. It was enqueued above. */
3222 else if (fast_tp_collecting
== 2)
3225 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3226 " single-stepping\n",
3229 if (can_hardware_single_step ())
3232 fatal ("moving out of jump pad single-stepping"
3233 " not implemented on this target");
3235 /* Postpone any pending signal. It was enqueued above. */
3239 /* If we have while-stepping actions in this thread set it stepping.
3240 If we have a signal to deliver, it may or may not be set to
3241 SIG_IGN, we don't know. Assume so, and allow collecting
3242 while-stepping into a signal handler. A possible smart thing to
3243 do would be to set an internal breakpoint at the signal return
3244 address, continue, and carry on catching this while-stepping
3245 action only when that breakpoint is hit. A future
3247 if (get_lwp_thread (lwp
)->while_stepping
!= NULL
3248 && can_hardware_single_step ())
3251 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
3256 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
3258 struct regcache
*regcache
= get_thread_regcache (current_inferior
, 1);
3259 CORE_ADDR pc
= (*the_low_target
.get_pc
) (regcache
);
3260 debug_printf (" resuming from pc 0x%lx\n", (long) pc
);
3263 /* If we have pending signals, consume one unless we are trying to
3264 reinsert a breakpoint or we're trying to finish a fast tracepoint
3266 if (lwp
->pending_signals
!= NULL
3267 && lwp
->bp_reinsert
== 0
3268 && fast_tp_collecting
== 0)
3270 struct pending_signals
**p_sig
;
3272 p_sig
= &lwp
->pending_signals
;
3273 while ((*p_sig
)->prev
!= NULL
)
3274 p_sig
= &(*p_sig
)->prev
;
3276 signal
= (*p_sig
)->signal
;
3277 if ((*p_sig
)->info
.si_signo
!= 0)
3278 ptrace (PTRACE_SETSIGINFO
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
3285 if (the_low_target
.prepare_to_resume
!= NULL
)
3286 the_low_target
.prepare_to_resume (lwp
);
3288 regcache_invalidate_thread (get_lwp_thread (lwp
));
3291 lwp
->stopped_by_watchpoint
= 0;
3292 lwp
->stepping
= step
;
3293 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (lwp
),
3294 (PTRACE_TYPE_ARG3
) 0,
3295 /* Coerce to a uintptr_t first to avoid potential gcc warning
3296 of coercing an 8 byte integer to a 4 byte pointer. */
3297 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
3299 current_inferior
= saved_inferior
;
3302 /* ESRCH from ptrace either means that the thread was already
3303 running (an error) or that it is gone (a race condition). If
3304 it's gone, we will get a notification the next time we wait,
3305 so we can ignore the error. We could differentiate these
3306 two, but it's tricky without waiting; the thread still exists
3307 as a zombie, so sending it signal 0 would succeed. So just
3312 perror_with_name ("ptrace");
3316 struct thread_resume_array
3318 struct thread_resume
*resume
;
3322 /* This function is called once per thread via find_inferior.
3323 ARG is a pointer to a thread_resume_array struct.
3324 We look up the thread specified by ENTRY in ARG, and mark the thread
3325 with a pointer to the appropriate resume request.
3327 This algorithm is O(threads * resume elements), but resume elements
3328 is small (and will remain small at least until GDB supports thread
3332 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3334 struct lwp_info
*lwp
;
3335 struct thread_info
*thread
;
3337 struct thread_resume_array
*r
;
3339 thread
= (struct thread_info
*) entry
;
3340 lwp
= get_thread_lwp (thread
);
3343 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3345 ptid_t ptid
= r
->resume
[ndx
].thread
;
3346 if (ptid_equal (ptid
, minus_one_ptid
)
3347 || ptid_equal (ptid
, entry
->id
)
3348 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
3350 || (ptid_get_pid (ptid
) == pid_of (lwp
)
3351 && (ptid_is_pid (ptid
)
3352 || ptid_get_lwp (ptid
) == -1)))
3354 if (r
->resume
[ndx
].kind
== resume_stop
3355 && thread
->last_resume_kind
== resume_stop
)
3358 debug_printf ("already %s LWP %ld at GDB's request\n",
3359 (thread
->last_status
.kind
3360 == TARGET_WAITKIND_STOPPED
)
3368 lwp
->resume
= &r
->resume
[ndx
];
3369 thread
->last_resume_kind
= lwp
->resume
->kind
;
3371 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
3372 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
3374 /* If we had a deferred signal to report, dequeue one now.
3375 This can happen if LWP gets more than one signal while
3376 trying to get out of a jump pad. */
3378 && !lwp
->status_pending_p
3379 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3381 lwp
->status_pending_p
= 1;
3384 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
3385 "leaving status pending.\n",
3386 WSTOPSIG (lwp
->status_pending
), lwpid_of (lwp
));
3393 /* No resume action for this thread. */
3399 /* find_inferior callback for linux_resume.
3400 Set *FLAG_P if this lwp has an interesting status pending. */
3403 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3405 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3407 /* LWPs which will not be resumed are not interesting, because
3408 we might not wait for them next time through linux_wait. */
3409 if (lwp
->resume
== NULL
)
3412 if (lwp
->status_pending_p
)
3413 * (int *) flag_p
= 1;
3418 /* Return 1 if this lwp that GDB wants running is stopped at an
3419 internal breakpoint that we need to step over. It assumes that any
3420 required STOP_PC adjustment has already been propagated to the
3421 inferior's regcache. */
3424 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3426 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3427 struct thread_info
*thread
;
3428 struct thread_info
*saved_inferior
;
3431 /* LWPs which will not be resumed are not interesting, because we
3432 might not wait for them next time through linux_wait. */
3437 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
3442 thread
= get_lwp_thread (lwp
);
3444 if (thread
->last_resume_kind
== resume_stop
)
3447 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
3453 gdb_assert (lwp
->suspended
>= 0);
3458 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
3463 if (!lwp
->need_step_over
)
3466 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (lwp
));
3469 if (lwp
->status_pending_p
)
3472 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
3478 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3482 /* If the PC has changed since we stopped, then don't do anything,
3483 and let the breakpoint/tracepoint be hit. This happens if, for
3484 instance, GDB handled the decr_pc_after_break subtraction itself,
3485 GDB is OOL stepping this thread, or the user has issued a "jump"
3486 command, or poked thread's registers herself. */
3487 if (pc
!= lwp
->stop_pc
)
3490 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
3491 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3492 lwpid_of (lwp
), paddress (lwp
->stop_pc
), paddress (pc
));
3494 lwp
->need_step_over
= 0;
3498 saved_inferior
= current_inferior
;
3499 current_inferior
= thread
;
3501 /* We can only step over breakpoints we know about. */
3502 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3504 /* Don't step over a breakpoint that GDB expects to hit
3505 though. If the condition is being evaluated on the target's side
3506 and it evaluate to false, step over this breakpoint as well. */
3507 if (gdb_breakpoint_here (pc
)
3508 && gdb_condition_true_at_breakpoint (pc
)
3509 && gdb_no_commands_at_breakpoint (pc
))
3512 debug_printf ("Need step over [LWP %ld]? yes, but found"
3513 " GDB breakpoint at 0x%s; skipping step over\n",
3514 lwpid_of (lwp
), paddress (pc
));
3516 current_inferior
= saved_inferior
;
3522 debug_printf ("Need step over [LWP %ld]? yes, "
3523 "found breakpoint at 0x%s\n",
3524 lwpid_of (lwp
), paddress (pc
));
3526 /* We've found an lwp that needs stepping over --- return 1 so
3527 that find_inferior stops looking. */
3528 current_inferior
= saved_inferior
;
3530 /* If the step over is cancelled, this is set again. */
3531 lwp
->need_step_over
= 0;
3536 current_inferior
= saved_inferior
;
3539 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
3541 lwpid_of (lwp
), paddress (pc
));
3546 /* Start a step-over operation on LWP. When LWP stopped at a
3547 breakpoint, to make progress, we need to remove the breakpoint out
3548 of the way. If we let other threads run while we do that, they may
3549 pass by the breakpoint location and miss hitting it. To avoid
3550 that, a step-over momentarily stops all threads while LWP is
3551 single-stepped while the breakpoint is temporarily uninserted from
3552 the inferior. When the single-step finishes, we reinsert the
3553 breakpoint, and let all threads that are supposed to be running,
3556 On targets that don't support hardware single-step, we don't
3557 currently support full software single-stepping. Instead, we only
3558 support stepping over the thread event breakpoint, by asking the
3559 low target where to place a reinsert breakpoint. Since this
3560 routine assumes the breakpoint being stepped over is a thread event
3561 breakpoint, it usually assumes the return address of the current
3562 function is a good enough place to set the reinsert breakpoint. */
3565 start_step_over (struct lwp_info
*lwp
)
3567 struct thread_info
*saved_inferior
;
3572 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
3575 stop_all_lwps (1, lwp
);
3576 gdb_assert (lwp
->suspended
== 0);
3579 debug_printf ("Done stopping all threads for step-over.\n");
3581 /* Note, we should always reach here with an already adjusted PC,
3582 either by GDB (if we're resuming due to GDB's request), or by our
3583 caller, if we just finished handling an internal breakpoint GDB
3584 shouldn't care about. */
3587 saved_inferior
= current_inferior
;
3588 current_inferior
= get_lwp_thread (lwp
);
3590 lwp
->bp_reinsert
= pc
;
3591 uninsert_breakpoints_at (pc
);
3592 uninsert_fast_tracepoint_jumps_at (pc
);
3594 if (can_hardware_single_step ())
3600 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3601 set_reinsert_breakpoint (raddr
);
3605 current_inferior
= saved_inferior
;
3607 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3609 /* Require next event from this LWP. */
3610 step_over_bkpt
= lwp
->head
.id
;
3614 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3615 start_step_over, if still there, and delete any reinsert
3616 breakpoints we've set, on non hardware single-step targets. */
3619 finish_step_over (struct lwp_info
*lwp
)
3621 if (lwp
->bp_reinsert
!= 0)
3624 debug_printf ("Finished step over.\n");
3626 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3627 may be no breakpoint to reinsert there by now. */
3628 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3629 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3631 lwp
->bp_reinsert
= 0;
3633 /* Delete any software-single-step reinsert breakpoints. No
3634 longer needed. We don't have to worry about other threads
3635 hitting this trap, and later not being able to explain it,
3636 because we were stepping over a breakpoint, and we hold all
3637 threads but LWP stopped while doing that. */
3638 if (!can_hardware_single_step ())
3639 delete_reinsert_breakpoints ();
3641 step_over_bkpt
= null_ptid
;
3648 /* This function is called once per thread. We check the thread's resume
3649 request, which will tell us whether to resume, step, or leave the thread
3650 stopped; and what signal, if any, it should be sent.
3652 For threads which we aren't explicitly told otherwise, we preserve
3653 the stepping flag; this is used for stepping over gdbserver-placed
3656 If pending_flags was set in any thread, we queue any needed
3657 signals, since we won't actually resume. We already have a pending
3658 event to report, so we don't need to preserve any step requests;
3659 they should be re-issued if necessary. */
3662 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3664 struct lwp_info
*lwp
;
3665 struct thread_info
*thread
;
3667 int leave_all_stopped
= * (int *) arg
;
3670 thread
= (struct thread_info
*) entry
;
3671 lwp
= get_thread_lwp (thread
);
3673 if (lwp
->resume
== NULL
)
3676 if (lwp
->resume
->kind
== resume_stop
)
3679 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (lwp
));
3684 debug_printf ("stopping LWP %ld\n", lwpid_of (lwp
));
3686 /* Stop the thread, and wait for the event asynchronously,
3687 through the event loop. */
3693 debug_printf ("already stopped LWP %ld\n",
3696 /* The LWP may have been stopped in an internal event that
3697 was not meant to be notified back to GDB (e.g., gdbserver
3698 breakpoint), so we should be reporting a stop event in
3701 /* If the thread already has a pending SIGSTOP, this is a
3702 no-op. Otherwise, something later will presumably resume
3703 the thread and this will cause it to cancel any pending
3704 operation, due to last_resume_kind == resume_stop. If
3705 the thread already has a pending status to report, we
3706 will still report it the next time we wait - see
3707 status_pending_p_callback. */
3709 /* If we already have a pending signal to report, then
3710 there's no need to queue a SIGSTOP, as this means we're
3711 midway through moving the LWP out of the jumppad, and we
3712 will report the pending signal as soon as that is
3714 if (lwp
->pending_signals_to_report
== NULL
)
3718 /* For stop requests, we're done. */
3720 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3724 /* If this thread which is about to be resumed has a pending status,
3725 then don't resume any threads - we can just report the pending
3726 status. Make sure to queue any signals that would otherwise be
3727 sent. In all-stop mode, we do this decision based on if *any*
3728 thread has a pending status. If there's a thread that needs the
3729 step-over-breakpoint dance, then don't resume any other thread
3730 but that particular one. */
3731 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
3736 debug_printf ("resuming LWP %ld\n", lwpid_of (lwp
));
3738 step
= (lwp
->resume
->kind
== resume_step
);
3739 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
3744 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (lwp
));
3746 /* If we have a new signal, enqueue the signal. */
3747 if (lwp
->resume
->sig
!= 0)
3749 struct pending_signals
*p_sig
;
3750 p_sig
= xmalloc (sizeof (*p_sig
));
3751 p_sig
->prev
= lwp
->pending_signals
;
3752 p_sig
->signal
= lwp
->resume
->sig
;
3753 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3755 /* If this is the same signal we were previously stopped by,
3756 make sure to queue its siginfo. We can ignore the return
3757 value of ptrace; if it fails, we'll skip
3758 PTRACE_SETSIGINFO. */
3759 if (WIFSTOPPED (lwp
->last_status
)
3760 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
3761 ptrace (PTRACE_GETSIGINFO
, lwpid_of (lwp
), (PTRACE_TYPE_ARG3
) 0,
3764 lwp
->pending_signals
= p_sig
;
3768 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3774 linux_resume (struct thread_resume
*resume_info
, size_t n
)
3776 struct thread_resume_array array
= { resume_info
, n
};
3777 struct lwp_info
*need_step_over
= NULL
;
3779 int leave_all_stopped
;
3784 debug_printf ("linux_resume:\n");
3787 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
3789 /* If there is a thread which would otherwise be resumed, which has
3790 a pending status, then don't resume any threads - we can just
3791 report the pending status. Make sure to queue any signals that
3792 would otherwise be sent. In non-stop mode, we'll apply this
3793 logic to each thread individually. We consume all pending events
3794 before considering to start a step-over (in all-stop). */
3797 find_inferior (&all_lwps
, resume_status_pending_p
, &any_pending
);
3799 /* If there is a thread which would otherwise be resumed, which is
3800 stopped at a breakpoint that needs stepping over, then don't
3801 resume any threads - have it step over the breakpoint with all
3802 other threads stopped, then resume all threads again. Make sure
3803 to queue any signals that would otherwise be delivered or
3805 if (!any_pending
&& supports_breakpoints ())
3807 = (struct lwp_info
*) find_inferior (&all_lwps
,
3808 need_step_over_p
, NULL
);
3810 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
3814 if (need_step_over
!= NULL
)
3815 debug_printf ("Not resuming all, need step over\n");
3816 else if (any_pending
)
3817 debug_printf ("Not resuming, all-stop and found "
3818 "an LWP with pending status\n");
3820 debug_printf ("Resuming, no pending status or step over needed\n");
3823 /* Even if we're leaving threads stopped, queue all signals we'd
3824 otherwise deliver. */
3825 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
3828 start_step_over (need_step_over
);
3832 debug_printf ("linux_resume done\n");
3837 /* This function is called once per thread. We check the thread's
3838 last resume request, which will tell us whether to resume, step, or
3839 leave the thread stopped. Any signal the client requested to be
3840 delivered has already been enqueued at this point.
3842 If any thread that GDB wants running is stopped at an internal
3843 breakpoint that needs stepping over, we start a step-over operation
3844 on that particular thread, and leave all others stopped. */
3847 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3849 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3850 struct thread_info
*thread
;
3857 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (lwp
));
3862 debug_printf (" LWP %ld already running\n", lwpid_of (lwp
));
3866 thread
= get_lwp_thread (lwp
);
3868 if (thread
->last_resume_kind
== resume_stop
3869 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
3872 debug_printf (" client wants LWP to remain %ld stopped\n",
3877 if (lwp
->status_pending_p
)
3880 debug_printf (" LWP %ld has pending status, leaving stopped\n",
3885 gdb_assert (lwp
->suspended
>= 0);
3890 debug_printf (" LWP %ld is suspended\n", lwpid_of (lwp
));
3894 if (thread
->last_resume_kind
== resume_stop
3895 && lwp
->pending_signals_to_report
== NULL
3896 && lwp
->collecting_fast_tracepoint
== 0)
3898 /* We haven't reported this LWP as stopped yet (otherwise, the
3899 last_status.kind check above would catch it, and we wouldn't
3900 reach here. This LWP may have been momentarily paused by a
3901 stop_all_lwps call while handling for example, another LWP's
3902 step-over. In that case, the pending expected SIGSTOP signal
3903 that was queued at vCont;t handling time will have already
3904 been consumed by wait_for_sigstop, and so we need to requeue
3905 another one here. Note that if the LWP already has a SIGSTOP
3906 pending, this is a no-op. */
3909 debug_printf ("Client wants LWP %ld to stop. "
3910 "Making sure it has a SIGSTOP pending\n",
3916 step
= thread
->last_resume_kind
== resume_step
;
3917 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3922 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
3924 struct lwp_info
*lwp
= (struct lwp_info
*) entry
;
3930 gdb_assert (lwp
->suspended
>= 0);
3932 return proceed_one_lwp (entry
, except
);
3935 /* When we finish a step-over, set threads running again. If there's
3936 another thread that may need a step-over, now's the time to start
3937 it. Eventually, we'll move all threads past their breakpoints. */
3940 proceed_all_lwps (void)
3942 struct lwp_info
*need_step_over
;
3944 /* If there is a thread which would otherwise be resumed, which is
3945 stopped at a breakpoint that needs stepping over, then don't
3946 resume any threads - have it step over the breakpoint with all
3947 other threads stopped, then resume all threads again. */
3949 if (supports_breakpoints ())
3952 = (struct lwp_info
*) find_inferior (&all_lwps
,
3953 need_step_over_p
, NULL
);
3955 if (need_step_over
!= NULL
)
3958 debug_printf ("proceed_all_lwps: found "
3959 "thread %ld needing a step-over\n",
3960 lwpid_of (need_step_over
));
3962 start_step_over (need_step_over
);
3968 debug_printf ("Proceeding, no step-over needed\n");
3970 find_inferior (&all_lwps
, proceed_one_lwp
, NULL
);
3973 /* Stopped LWPs that the client wanted to be running, that don't have
3974 pending statuses, are set to run again, except for EXCEPT, if not
3975 NULL. This undoes a stop_all_lwps call. */
3978 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
3984 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
3987 debug_printf ("unstopping all lwps\n");
3991 find_inferior (&all_lwps
, unsuspend_and_proceed_one_lwp
, except
);
3993 find_inferior (&all_lwps
, proceed_one_lwp
, except
);
3997 debug_printf ("unstop_all_lwps done\n");
4003 #ifdef HAVE_LINUX_REGSETS
4005 #define use_linux_regsets 1
4007 /* Returns true if REGSET has been disabled. */
4010 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
4012 return (info
->disabled_regsets
!= NULL
4013 && info
->disabled_regsets
[regset
- info
->regsets
]);
4016 /* Disable REGSET. */
4019 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
4023 dr_offset
= regset
- info
->regsets
;
4024 if (info
->disabled_regsets
== NULL
)
4025 info
->disabled_regsets
= xcalloc (1, info
->num_regsets
);
4026 info
->disabled_regsets
[dr_offset
] = 1;
4030 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
4031 struct regcache
*regcache
)
4033 struct regset_info
*regset
;
4034 int saw_general_regs
= 0;
4038 regset
= regsets_info
->regsets
;
4040 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4041 while (regset
->size
>= 0)
4046 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
4052 buf
= xmalloc (regset
->size
);
4054 nt_type
= regset
->nt_type
;
4058 iov
.iov_len
= regset
->size
;
4059 data
= (void *) &iov
;
4065 res
= ptrace (regset
->get_request
, pid
,
4066 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4068 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4074 /* If we get EIO on a regset, do not try it again for
4075 this process mode. */
4076 disable_regset (regsets_info
, regset
);
4083 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4088 else if (regset
->type
== GENERAL_REGS
)
4089 saw_general_regs
= 1;
4090 regset
->store_function (regcache
, buf
);
4094 if (saw_general_regs
)
4101 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
4102 struct regcache
*regcache
)
4104 struct regset_info
*regset
;
4105 int saw_general_regs
= 0;
4109 regset
= regsets_info
->regsets
;
4111 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4112 while (regset
->size
>= 0)
4117 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
4123 buf
= xmalloc (regset
->size
);
4125 /* First fill the buffer with the current register set contents,
4126 in case there are any items in the kernel's regset that are
4127 not in gdbserver's regcache. */
4129 nt_type
= regset
->nt_type
;
4133 iov
.iov_len
= regset
->size
;
4134 data
= (void *) &iov
;
4140 res
= ptrace (regset
->get_request
, pid
,
4141 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4143 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4148 /* Then overlay our cached registers on that. */
4149 regset
->fill_function (regcache
, buf
);
4151 /* Only now do we write the register set. */
4153 res
= ptrace (regset
->set_request
, pid
,
4154 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4156 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4164 /* If we get EIO on a regset, do not try it again for
4165 this process mode. */
4166 disable_regset (regsets_info
, regset
);
4170 else if (errno
== ESRCH
)
4172 /* At this point, ESRCH should mean the process is
4173 already gone, in which case we simply ignore attempts
4174 to change its registers. See also the related
4175 comment in linux_resume_one_lwp. */
4181 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4184 else if (regset
->type
== GENERAL_REGS
)
4185 saw_general_regs
= 1;
4189 if (saw_general_regs
)
4195 #else /* !HAVE_LINUX_REGSETS */
4197 #define use_linux_regsets 0
4198 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
4199 #define regsets_store_inferior_registers(regsets_info, regcache) 1
4203 /* Return 1 if register REGNO is supported by one of the regset ptrace
4204 calls or 0 if it has to be transferred individually. */
4207 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
4209 unsigned char mask
= 1 << (regno
% 8);
4210 size_t index
= regno
/ 8;
4212 return (use_linux_regsets
4213 && (regs_info
->regset_bitmap
== NULL
4214 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
4217 #ifdef HAVE_LINUX_USRREGS
4220 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
4224 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
4225 error ("Invalid register number %d.", regnum
);
4227 addr
= usrregs
->regmap
[regnum
];
4232 /* Fetch one register. */
4234 fetch_register (const struct usrregs_info
*usrregs
,
4235 struct regcache
*regcache
, int regno
)
4242 if (regno
>= usrregs
->num_regs
)
4244 if ((*the_low_target
.cannot_fetch_register
) (regno
))
4247 regaddr
= register_addr (usrregs
, regno
);
4251 size
= ((register_size (regcache
->tdesc
, regno
)
4252 + sizeof (PTRACE_XFER_TYPE
) - 1)
4253 & -sizeof (PTRACE_XFER_TYPE
));
4254 buf
= alloca (size
);
4256 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4257 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4260 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
4261 ptrace (PTRACE_PEEKUSER
, pid
,
4262 /* Coerce to a uintptr_t first to avoid potential gcc warning
4263 of coercing an 8 byte integer to a 4 byte pointer. */
4264 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
4265 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4267 error ("reading register %d: %s", regno
, strerror (errno
));
4270 if (the_low_target
.supply_ptrace_register
)
4271 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
4273 supply_register (regcache
, regno
, buf
);
4276 /* Store one register. */
4278 store_register (const struct usrregs_info
*usrregs
,
4279 struct regcache
*regcache
, int regno
)
4286 if (regno
>= usrregs
->num_regs
)
4288 if ((*the_low_target
.cannot_store_register
) (regno
))
4291 regaddr
= register_addr (usrregs
, regno
);
4295 size
= ((register_size (regcache
->tdesc
, regno
)
4296 + sizeof (PTRACE_XFER_TYPE
) - 1)
4297 & -sizeof (PTRACE_XFER_TYPE
));
4298 buf
= alloca (size
);
4299 memset (buf
, 0, size
);
4301 if (the_low_target
.collect_ptrace_register
)
4302 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
4304 collect_register (regcache
, regno
, buf
);
4306 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4307 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4310 ptrace (PTRACE_POKEUSER
, pid
,
4311 /* Coerce to a uintptr_t first to avoid potential gcc warning
4312 about coercing an 8 byte integer to a 4 byte pointer. */
4313 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
4314 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
4317 /* At this point, ESRCH should mean the process is
4318 already gone, in which case we simply ignore attempts
4319 to change its registers. See also the related
4320 comment in linux_resume_one_lwp. */
4324 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
4325 error ("writing register %d: %s", regno
, strerror (errno
));
4327 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4331 /* Fetch all registers, or just one, from the child process.
4332 If REGNO is -1, do this for all registers, skipping any that are
4333 assumed to have been retrieved by regsets_fetch_inferior_registers,
4334 unless ALL is non-zero.
4335 Otherwise, REGNO specifies which register (so we can save time). */
4337 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
4338 struct regcache
*regcache
, int regno
, int all
)
4340 struct usrregs_info
*usr
= regs_info
->usrregs
;
4344 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4345 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4346 fetch_register (usr
, regcache
, regno
);
4349 fetch_register (usr
, regcache
, regno
);
4352 /* Store our register values back into the inferior.
4353 If REGNO is -1, do this for all registers, skipping any that are
4354 assumed to have been saved by regsets_store_inferior_registers,
4355 unless ALL is non-zero.
4356 Otherwise, REGNO specifies which register (so we can save time). */
4358 usr_store_inferior_registers (const struct regs_info
*regs_info
,
4359 struct regcache
*regcache
, int regno
, int all
)
4361 struct usrregs_info
*usr
= regs_info
->usrregs
;
4365 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4366 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4367 store_register (usr
, regcache
, regno
);
4370 store_register (usr
, regcache
, regno
);
4373 #else /* !HAVE_LINUX_USRREGS */
4375 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4376 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4382 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4386 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
4390 if (the_low_target
.fetch_register
!= NULL
4391 && regs_info
->usrregs
!= NULL
)
4392 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
4393 (*the_low_target
.fetch_register
) (regcache
, regno
);
4395 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
4396 if (regs_info
->usrregs
!= NULL
)
4397 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
4401 if (the_low_target
.fetch_register
!= NULL
4402 && (*the_low_target
.fetch_register
) (regcache
, regno
))
4405 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
4407 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
4409 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
4410 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
4415 linux_store_registers (struct regcache
*regcache
, int regno
)
4419 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
4423 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
4425 if (regs_info
->usrregs
!= NULL
)
4426 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
4430 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
4432 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
4434 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
4435 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
4440 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4441 to debugger memory starting at MYADDR. */
4444 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4446 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4447 register PTRACE_XFER_TYPE
*buffer
;
4448 register CORE_ADDR addr
;
4455 /* Try using /proc. Don't bother for one word. */
4456 if (len
>= 3 * sizeof (long))
4460 /* We could keep this file open and cache it - possibly one per
4461 thread. That requires some juggling, but is even faster. */
4462 sprintf (filename
, "/proc/%d/mem", pid
);
4463 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4467 /* If pread64 is available, use it. It's faster if the kernel
4468 supports it (only one syscall), and it's 64-bit safe even on
4469 32-bit platforms (for instance, SPARC debugging a SPARC64
4472 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
4475 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
4476 bytes
= read (fd
, myaddr
, len
);
4483 /* Some data was read, we'll try to get the rest with ptrace. */
4493 /* Round starting address down to longword boundary. */
4494 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4495 /* Round ending address up; get number of longwords that makes. */
4496 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4497 / sizeof (PTRACE_XFER_TYPE
));
4498 /* Allocate buffer of that many longwords. */
4499 buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4501 /* Read all the longwords */
4503 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4505 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4506 about coercing an 8 byte integer to a 4 byte pointer. */
4507 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4508 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4509 (PTRACE_TYPE_ARG4
) 0);
4515 /* Copy appropriate bytes out of the buffer. */
4518 i
*= sizeof (PTRACE_XFER_TYPE
);
4519 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
4521 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4528 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4529 memory at MEMADDR. On failure (cannot write to the inferior)
4530 returns the value of errno. Always succeeds if LEN is zero. */
4533 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4536 /* Round starting address down to longword boundary. */
4537 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4538 /* Round ending address up; get number of longwords that makes. */
4540 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4541 / sizeof (PTRACE_XFER_TYPE
);
4543 /* Allocate buffer of that many longwords. */
4544 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4545 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4547 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4551 /* Zero length write always succeeds. */
4557 /* Dump up to four bytes. */
4558 unsigned int val
= * (unsigned int *) myaddr
;
4564 val
= val
& 0xffffff;
4565 debug_printf ("Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4566 val
, (long)memaddr
);
4569 /* Fill start and end extra bytes of buffer with existing memory data. */
4572 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4573 about coercing an 8 byte integer to a 4 byte pointer. */
4574 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4575 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4576 (PTRACE_TYPE_ARG4
) 0);
4584 = ptrace (PTRACE_PEEKTEXT
, pid
,
4585 /* Coerce to a uintptr_t first to avoid potential gcc warning
4586 about coercing an 8 byte integer to a 4 byte pointer. */
4587 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
4588 * sizeof (PTRACE_XFER_TYPE
)),
4589 (PTRACE_TYPE_ARG4
) 0);
4594 /* Copy data to be written over corresponding part of buffer. */
4596 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4599 /* Write the entire buffer. */
4601 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4604 ptrace (PTRACE_POKETEXT
, pid
,
4605 /* Coerce to a uintptr_t first to avoid potential gcc warning
4606 about coercing an 8 byte integer to a 4 byte pointer. */
4607 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4608 (PTRACE_TYPE_ARG4
) buffer
[i
]);
4617 linux_look_up_symbols (void)
4619 #ifdef USE_THREAD_DB
4620 struct process_info
*proc
= current_process ();
4622 if (proc
->private->thread_db
!= NULL
)
4625 /* If the kernel supports tracing clones, then we don't need to
4626 use the magic thread event breakpoint to learn about
4628 thread_db_init (!linux_supports_traceclone ());
4633 linux_request_interrupt (void)
4635 extern unsigned long signal_pid
;
4637 if (!ptid_equal (cont_thread
, null_ptid
)
4638 && !ptid_equal (cont_thread
, minus_one_ptid
))
4640 struct lwp_info
*lwp
;
4643 lwp
= get_thread_lwp (current_inferior
);
4644 lwpid
= lwpid_of (lwp
);
4645 kill_lwp (lwpid
, SIGINT
);
4648 kill_lwp (signal_pid
, SIGINT
);
4651 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4652 to debugger memory starting at MYADDR. */
4655 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4657 char filename
[PATH_MAX
];
4659 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4661 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4663 fd
= open (filename
, O_RDONLY
);
4667 if (offset
!= (CORE_ADDR
) 0
4668 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4671 n
= read (fd
, myaddr
, len
);
4678 /* These breakpoint and watchpoint related wrapper functions simply
4679 pass on the function call if the target has registered a
4680 corresponding function. */
4683 linux_insert_point (char type
, CORE_ADDR addr
, int len
)
4685 if (the_low_target
.insert_point
!= NULL
)
4686 return the_low_target
.insert_point (type
, addr
, len
);
4688 /* Unsupported (see target.h). */
4693 linux_remove_point (char type
, CORE_ADDR addr
, int len
)
4695 if (the_low_target
.remove_point
!= NULL
)
4696 return the_low_target
.remove_point (type
, addr
, len
);
4698 /* Unsupported (see target.h). */
4703 linux_stopped_by_watchpoint (void)
4705 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4707 return lwp
->stopped_by_watchpoint
;
4711 linux_stopped_data_address (void)
4713 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
4715 return lwp
->stopped_data_address
;
4718 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
4719 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
4720 && defined(PT_TEXT_END_ADDR)
4722 /* This is only used for targets that define PT_TEXT_ADDR,
4723 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
4724 the target has different ways of acquiring this information, like
4727 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4728 to tell gdb about. */
4731 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
4733 unsigned long text
, text_end
, data
;
4734 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
4738 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
4739 (PTRACE_TYPE_ARG4
) 0);
4740 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
4741 (PTRACE_TYPE_ARG4
) 0);
4742 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
4743 (PTRACE_TYPE_ARG4
) 0);
4747 /* Both text and data offsets produced at compile-time (and so
4748 used by gdb) are relative to the beginning of the program,
4749 with the data segment immediately following the text segment.
4750 However, the actual runtime layout in memory may put the data
4751 somewhere else, so when we send gdb a data base-address, we
4752 use the real data base address and subtract the compile-time
4753 data base-address from it (which is just the length of the
4754 text segment). BSS immediately follows data in both
4757 *data_p
= data
- (text_end
- text
);
4766 linux_qxfer_osdata (const char *annex
,
4767 unsigned char *readbuf
, unsigned const char *writebuf
,
4768 CORE_ADDR offset
, int len
)
4770 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
4773 /* Convert a native/host siginfo object, into/from the siginfo in the
4774 layout of the inferiors' architecture. */
4777 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
4781 if (the_low_target
.siginfo_fixup
!= NULL
)
4782 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
4784 /* If there was no callback, or the callback didn't do anything,
4785 then just do a straight memcpy. */
4789 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
4791 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
4796 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
4797 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
4801 char inf_siginfo
[sizeof (siginfo_t
)];
4803 if (current_inferior
== NULL
)
4806 pid
= lwpid_of (get_thread_lwp (current_inferior
));
4809 debug_printf ("%s siginfo for lwp %d.\n",
4810 readbuf
!= NULL
? "Reading" : "Writing",
4813 if (offset
>= sizeof (siginfo
))
4816 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
4819 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4820 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4821 inferior with a 64-bit GDBSERVER should look the same as debugging it
4822 with a 32-bit GDBSERVER, we need to convert it. */
4823 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
4825 if (offset
+ len
> sizeof (siginfo
))
4826 len
= sizeof (siginfo
) - offset
;
4828 if (readbuf
!= NULL
)
4829 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
4832 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
4834 /* Convert back to ptrace layout before flushing it out. */
4835 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
4837 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
4844 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4845 so we notice when children change state; as the handler for the
4846 sigsuspend in my_waitpid. */
4849 sigchld_handler (int signo
)
4851 int old_errno
= errno
;
4857 /* fprintf is not async-signal-safe, so call write
4859 if (write (2, "sigchld_handler\n",
4860 sizeof ("sigchld_handler\n") - 1) < 0)
4861 break; /* just ignore */
4865 if (target_is_async_p ())
4866 async_file_mark (); /* trigger a linux_wait */
4872 linux_supports_non_stop (void)
4878 linux_async (int enable
)
4880 int previous
= (linux_event_pipe
[0] != -1);
4883 debug_printf ("linux_async (%d), previous=%d\n",
4886 if (previous
!= enable
)
4889 sigemptyset (&mask
);
4890 sigaddset (&mask
, SIGCHLD
);
4892 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
4896 if (pipe (linux_event_pipe
) == -1)
4897 fatal ("creating event pipe failed.");
4899 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
4900 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
4902 /* Register the event loop handler. */
4903 add_file_handler (linux_event_pipe
[0],
4904 handle_target_event
, NULL
);
4906 /* Always trigger a linux_wait. */
4911 delete_file_handler (linux_event_pipe
[0]);
4913 close (linux_event_pipe
[0]);
4914 close (linux_event_pipe
[1]);
4915 linux_event_pipe
[0] = -1;
4916 linux_event_pipe
[1] = -1;
4919 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
4926 linux_start_non_stop (int nonstop
)
4928 /* Register or unregister from event-loop accordingly. */
4929 linux_async (nonstop
);
4934 linux_supports_multi_process (void)
4940 linux_supports_disable_randomization (void)
4942 #ifdef HAVE_PERSONALITY
4950 linux_supports_agent (void)
4956 linux_supports_range_stepping (void)
4958 if (*the_low_target
.supports_range_stepping
== NULL
)
4961 return (*the_low_target
.supports_range_stepping
) ();
4964 /* Enumerate spufs IDs for process PID. */
4966 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
4972 struct dirent
*entry
;
4974 sprintf (path
, "/proc/%ld/fd", pid
);
4975 dir
= opendir (path
);
4980 while ((entry
= readdir (dir
)) != NULL
)
4986 fd
= atoi (entry
->d_name
);
4990 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
4991 if (stat (path
, &st
) != 0)
4993 if (!S_ISDIR (st
.st_mode
))
4996 if (statfs (path
, &stfs
) != 0)
4998 if (stfs
.f_type
!= SPUFS_MAGIC
)
5001 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
5003 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
5013 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
5014 object type, using the /proc file system. */
5016 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
5017 unsigned const char *writebuf
,
5018 CORE_ADDR offset
, int len
)
5020 long pid
= lwpid_of (get_thread_lwp (current_inferior
));
5025 if (!writebuf
&& !readbuf
)
5033 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5036 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
5037 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5042 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5049 ret
= write (fd
, writebuf
, (size_t) len
);
5051 ret
= read (fd
, readbuf
, (size_t) len
);
5057 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5058 struct target_loadseg
5060 /* Core address to which the segment is mapped. */
5062 /* VMA recorded in the program header. */
5064 /* Size of this segment in memory. */
5068 # if defined PT_GETDSBT
5069 struct target_loadmap
5071 /* Protocol version number, must be zero. */
5073 /* Pointer to the DSBT table, its size, and the DSBT index. */
5074 unsigned *dsbt_table
;
5075 unsigned dsbt_size
, dsbt_index
;
5076 /* Number of segments in this map. */
5078 /* The actual memory map. */
5079 struct target_loadseg segs
[/*nsegs*/];
5081 # define LINUX_LOADMAP PT_GETDSBT
5082 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5083 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5085 struct target_loadmap
5087 /* Protocol version number, must be zero. */
5089 /* Number of segments in this map. */
5091 /* The actual memory map. */
5092 struct target_loadseg segs
[/*nsegs*/];
5094 # define LINUX_LOADMAP PTRACE_GETFDPIC
5095 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5096 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5100 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
5101 unsigned char *myaddr
, unsigned int len
)
5103 int pid
= lwpid_of (get_thread_lwp (current_inferior
));
5105 struct target_loadmap
*data
= NULL
;
5106 unsigned int actual_length
, copy_length
;
5108 if (strcmp (annex
, "exec") == 0)
5109 addr
= (int) LINUX_LOADMAP_EXEC
;
5110 else if (strcmp (annex
, "interp") == 0)
5111 addr
= (int) LINUX_LOADMAP_INTERP
;
5115 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
5121 actual_length
= sizeof (struct target_loadmap
)
5122 + sizeof (struct target_loadseg
) * data
->nsegs
;
5124 if (offset
< 0 || offset
> actual_length
)
5127 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
5128 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
5132 # define linux_read_loadmap NULL
5133 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5136 linux_process_qsupported (const char *query
)
5138 if (the_low_target
.process_qsupported
!= NULL
)
5139 the_low_target
.process_qsupported (query
);
5143 linux_supports_tracepoints (void)
5145 if (*the_low_target
.supports_tracepoints
== NULL
)
5148 return (*the_low_target
.supports_tracepoints
) ();
5152 linux_read_pc (struct regcache
*regcache
)
5154 if (the_low_target
.get_pc
== NULL
)
5157 return (*the_low_target
.get_pc
) (regcache
);
5161 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
5163 gdb_assert (the_low_target
.set_pc
!= NULL
);
5165 (*the_low_target
.set_pc
) (regcache
, pc
);
5169 linux_thread_stopped (struct thread_info
*thread
)
5171 return get_thread_lwp (thread
)->stopped
;
5174 /* This exposes stop-all-threads functionality to other modules. */
5177 linux_pause_all (int freeze
)
5179 stop_all_lwps (freeze
, NULL
);
5182 /* This exposes unstop-all-threads functionality to other gdbserver
5186 linux_unpause_all (int unfreeze
)
5188 unstop_all_lwps (unfreeze
, NULL
);
5192 linux_prepare_to_access_memory (void)
5194 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5197 linux_pause_all (1);
5202 linux_done_accessing_memory (void)
5204 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5207 linux_unpause_all (1);
5211 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5212 CORE_ADDR collector
,
5215 CORE_ADDR
*jump_entry
,
5216 CORE_ADDR
*trampoline
,
5217 ULONGEST
*trampoline_size
,
5218 unsigned char *jjump_pad_insn
,
5219 ULONGEST
*jjump_pad_insn_size
,
5220 CORE_ADDR
*adjusted_insn_addr
,
5221 CORE_ADDR
*adjusted_insn_addr_end
,
5224 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5225 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5226 jump_entry
, trampoline
, trampoline_size
,
5227 jjump_pad_insn
, jjump_pad_insn_size
,
5228 adjusted_insn_addr
, adjusted_insn_addr_end
,
5232 static struct emit_ops
*
5233 linux_emit_ops (void)
5235 if (the_low_target
.emit_ops
!= NULL
)
5236 return (*the_low_target
.emit_ops
) ();
5242 linux_get_min_fast_tracepoint_insn_len (void)
5244 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5247 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5250 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5251 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5253 char filename
[PATH_MAX
];
5255 const int auxv_size
= is_elf64
5256 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5257 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5259 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5261 fd
= open (filename
, O_RDONLY
);
5267 while (read (fd
, buf
, auxv_size
) == auxv_size
5268 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5272 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5274 switch (aux
->a_type
)
5277 *phdr_memaddr
= aux
->a_un
.a_val
;
5280 *num_phdr
= aux
->a_un
.a_val
;
5286 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5288 switch (aux
->a_type
)
5291 *phdr_memaddr
= aux
->a_un
.a_val
;
5294 *num_phdr
= aux
->a_un
.a_val
;
5302 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5304 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5305 "phdr_memaddr = %ld, phdr_num = %d",
5306 (long) *phdr_memaddr
, *num_phdr
);
5313 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5316 get_dynamic (const int pid
, const int is_elf64
)
5318 CORE_ADDR phdr_memaddr
, relocation
;
5320 unsigned char *phdr_buf
;
5321 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5323 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5326 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5327 phdr_buf
= alloca (num_phdr
* phdr_size
);
5329 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5332 /* Compute relocation: it is expected to be 0 for "regular" executables,
5333 non-zero for PIE ones. */
5335 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5338 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5340 if (p
->p_type
== PT_PHDR
)
5341 relocation
= phdr_memaddr
- p
->p_vaddr
;
5345 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5347 if (p
->p_type
== PT_PHDR
)
5348 relocation
= phdr_memaddr
- p
->p_vaddr
;
5351 if (relocation
== -1)
5353 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5354 any real world executables, including PIE executables, have always
5355 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5356 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5357 or present DT_DEBUG anyway (fpc binaries are statically linked).
5359 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5361 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5366 for (i
= 0; i
< num_phdr
; i
++)
5370 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5372 if (p
->p_type
== PT_DYNAMIC
)
5373 return p
->p_vaddr
+ relocation
;
5377 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5379 if (p
->p_type
== PT_DYNAMIC
)
5380 return p
->p_vaddr
+ relocation
;
5387 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5388 can be 0 if the inferior does not yet have the library list initialized.
5389 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
5390 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
5393 get_r_debug (const int pid
, const int is_elf64
)
5395 CORE_ADDR dynamic_memaddr
;
5396 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5397 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5400 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5401 if (dynamic_memaddr
== 0)
5404 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5408 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5409 #ifdef DT_MIPS_RLD_MAP
5413 unsigned char buf
[sizeof (Elf64_Xword
)];
5417 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5419 if (linux_read_memory (dyn
->d_un
.d_val
,
5420 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5425 #endif /* DT_MIPS_RLD_MAP */
5427 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5428 map
= dyn
->d_un
.d_val
;
5430 if (dyn
->d_tag
== DT_NULL
)
5435 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5436 #ifdef DT_MIPS_RLD_MAP
5440 unsigned char buf
[sizeof (Elf32_Word
)];
5444 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5446 if (linux_read_memory (dyn
->d_un
.d_val
,
5447 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5452 #endif /* DT_MIPS_RLD_MAP */
5454 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5455 map
= dyn
->d_un
.d_val
;
5457 if (dyn
->d_tag
== DT_NULL
)
5461 dynamic_memaddr
+= dyn_size
;
5467 /* Read one pointer from MEMADDR in the inferior. */
5470 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5474 /* Go through a union so this works on either big or little endian
5475 hosts, when the inferior's pointer size is smaller than the size
5476 of CORE_ADDR. It is assumed the inferior's endianness is the
5477 same of the superior's. */
5480 CORE_ADDR core_addr
;
5485 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
5488 if (ptr_size
== sizeof (CORE_ADDR
))
5489 *ptr
= addr
.core_addr
;
5490 else if (ptr_size
== sizeof (unsigned int))
5493 gdb_assert_not_reached ("unhandled pointer size");
5498 struct link_map_offsets
5500 /* Offset and size of r_debug.r_version. */
5501 int r_version_offset
;
5503 /* Offset and size of r_debug.r_map. */
5506 /* Offset to l_addr field in struct link_map. */
5509 /* Offset to l_name field in struct link_map. */
5512 /* Offset to l_ld field in struct link_map. */
5515 /* Offset to l_next field in struct link_map. */
5518 /* Offset to l_prev field in struct link_map. */
5522 /* Construct qXfer:libraries-svr4:read reply. */
5525 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5526 unsigned const char *writebuf
,
5527 CORE_ADDR offset
, int len
)
5530 unsigned document_len
;
5531 struct process_info_private
*const priv
= current_process ()->private;
5532 char filename
[PATH_MAX
];
5535 static const struct link_map_offsets lmo_32bit_offsets
=
5537 0, /* r_version offset. */
5538 4, /* r_debug.r_map offset. */
5539 0, /* l_addr offset in link_map. */
5540 4, /* l_name offset in link_map. */
5541 8, /* l_ld offset in link_map. */
5542 12, /* l_next offset in link_map. */
5543 16 /* l_prev offset in link_map. */
5546 static const struct link_map_offsets lmo_64bit_offsets
=
5548 0, /* r_version offset. */
5549 8, /* r_debug.r_map offset. */
5550 0, /* l_addr offset in link_map. */
5551 8, /* l_name offset in link_map. */
5552 16, /* l_ld offset in link_map. */
5553 24, /* l_next offset in link_map. */
5554 32 /* l_prev offset in link_map. */
5556 const struct link_map_offsets
*lmo
;
5557 unsigned int machine
;
5559 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
5560 int allocated
= 1024;
5562 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5563 int header_done
= 0;
5565 if (writebuf
!= NULL
)
5567 if (readbuf
== NULL
)
5570 pid
= lwpid_of (get_thread_lwp (current_inferior
));
5571 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5572 is_elf64
= elf_64_file_p (filename
, &machine
);
5573 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5574 ptr_size
= is_elf64
? 8 : 4;
5576 while (annex
[0] != '\0')
5582 sep
= strchr (annex
, '=');
5587 if (len
== 5 && strncmp (annex
, "start", 5) == 0)
5589 else if (len
== 4 && strncmp (annex
, "prev", 4) == 0)
5593 annex
= strchr (sep
, ';');
5600 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
5607 if (priv
->r_debug
== 0)
5608 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5610 /* We failed to find DT_DEBUG. Such situation will not change
5611 for this inferior - do not retry it. Report it to GDB as
5612 E01, see for the reasons at the GDB solib-svr4.c side. */
5613 if (priv
->r_debug
== (CORE_ADDR
) -1)
5616 if (priv
->r_debug
!= 0)
5618 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5619 (unsigned char *) &r_version
,
5620 sizeof (r_version
)) != 0
5623 warning ("unexpected r_debug version %d", r_version
);
5625 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5626 &lm_addr
, ptr_size
) != 0)
5628 warning ("unable to read r_map from 0x%lx",
5629 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5634 document
= xmalloc (allocated
);
5635 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5636 p
= document
+ strlen (document
);
5639 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5640 &l_name
, ptr_size
) == 0
5641 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5642 &l_addr
, ptr_size
) == 0
5643 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5644 &l_ld
, ptr_size
) == 0
5645 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5646 &l_prev
, ptr_size
) == 0
5647 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5648 &l_next
, ptr_size
) == 0)
5650 unsigned char libname
[PATH_MAX
];
5652 if (lm_prev
!= l_prev
)
5654 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5655 (long) lm_prev
, (long) l_prev
);
5659 /* Ignore the first entry even if it has valid name as the first entry
5660 corresponds to the main executable. The first entry should not be
5661 skipped if the dynamic loader was loaded late by a static executable
5662 (see solib-svr4.c parameter ignore_first). But in such case the main
5663 executable does not have PT_DYNAMIC present and this function already
5664 exited above due to failed get_r_debug. */
5667 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5672 /* Not checking for error because reading may stop before
5673 we've got PATH_MAX worth of characters. */
5675 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5676 libname
[sizeof (libname
) - 1] = '\0';
5677 if (libname
[0] != '\0')
5679 /* 6x the size for xml_escape_text below. */
5680 size_t len
= 6 * strlen ((char *) libname
);
5685 /* Terminate `<library-list-svr4'. */
5690 while (allocated
< p
- document
+ len
+ 200)
5692 /* Expand to guarantee sufficient storage. */
5693 uintptr_t document_len
= p
- document
;
5695 document
= xrealloc (document
, 2 * allocated
);
5697 p
= document
+ document_len
;
5700 name
= xml_escape_text ((char *) libname
);
5701 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
5702 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5703 name
, (unsigned long) lm_addr
,
5704 (unsigned long) l_addr
, (unsigned long) l_ld
);
5715 /* Empty list; terminate `<library-list-svr4'. */
5719 strcpy (p
, "</library-list-svr4>");
5721 document_len
= strlen (document
);
5722 if (offset
< document_len
)
5723 document_len
-= offset
;
5726 if (len
> document_len
)
5729 memcpy (readbuf
, document
+ offset
, len
);
5735 #ifdef HAVE_LINUX_BTRACE
5737 /* See to_enable_btrace target method. */
5739 static struct btrace_target_info
*
5740 linux_low_enable_btrace (ptid_t ptid
)
5742 struct btrace_target_info
*tinfo
;
5744 tinfo
= linux_enable_btrace (ptid
);
5748 struct thread_info
*thread
= find_thread_ptid (ptid
);
5749 struct regcache
*regcache
= get_thread_regcache (thread
, 0);
5751 tinfo
->ptr_bits
= register_size (regcache
->tdesc
, 0) * 8;
5757 /* See to_disable_btrace target method. */
5760 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
5762 enum btrace_error err
;
5764 err
= linux_disable_btrace (tinfo
);
5765 return (err
== BTRACE_ERR_NONE
? 0 : -1);
5768 /* See to_read_btrace target method. */
5771 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
5774 VEC (btrace_block_s
) *btrace
;
5775 struct btrace_block
*block
;
5776 enum btrace_error err
;
5780 err
= linux_read_btrace (&btrace
, tinfo
, type
);
5781 if (err
!= BTRACE_ERR_NONE
)
5783 if (err
== BTRACE_ERR_OVERFLOW
)
5784 buffer_grow_str0 (buffer
, "E.Overflow.");
5786 buffer_grow_str0 (buffer
, "E.Generic Error.");
5791 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
5792 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
5794 for (i
= 0; VEC_iterate (btrace_block_s
, btrace
, i
, block
); i
++)
5795 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
5796 paddress (block
->begin
), paddress (block
->end
));
5798 buffer_grow_str0 (buffer
, "</btrace>\n");
5800 VEC_free (btrace_block_s
, btrace
);
5804 #endif /* HAVE_LINUX_BTRACE */
5806 static struct target_ops linux_target_ops
= {
5807 linux_create_inferior
,
5816 linux_fetch_registers
,
5817 linux_store_registers
,
5818 linux_prepare_to_access_memory
,
5819 linux_done_accessing_memory
,
5822 linux_look_up_symbols
,
5823 linux_request_interrupt
,
5827 linux_stopped_by_watchpoint
,
5828 linux_stopped_data_address
,
5829 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5830 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5831 && defined(PT_TEXT_END_ADDR)
5836 #ifdef USE_THREAD_DB
5837 thread_db_get_tls_address
,
5842 hostio_last_error_from_errno
,
5845 linux_supports_non_stop
,
5847 linux_start_non_stop
,
5848 linux_supports_multi_process
,
5849 #ifdef USE_THREAD_DB
5850 thread_db_handle_monitor_command
,
5854 linux_common_core_of_thread
,
5856 linux_process_qsupported
,
5857 linux_supports_tracepoints
,
5860 linux_thread_stopped
,
5864 linux_cancel_breakpoints
,
5865 linux_stabilize_threads
,
5866 linux_install_fast_tracepoint_jump_pad
,
5868 linux_supports_disable_randomization
,
5869 linux_get_min_fast_tracepoint_insn_len
,
5870 linux_qxfer_libraries_svr4
,
5871 linux_supports_agent
,
5872 #ifdef HAVE_LINUX_BTRACE
5873 linux_supports_btrace
,
5874 linux_low_enable_btrace
,
5875 linux_low_disable_btrace
,
5876 linux_low_read_btrace
,
5883 linux_supports_range_stepping
,
5887 linux_init_signals ()
5889 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5890 to find what the cancel signal actually is. */
5891 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
5892 signal (__SIGRTMIN
+1, SIG_IGN
);
5896 #ifdef HAVE_LINUX_REGSETS
5898 initialize_regsets_info (struct regsets_info
*info
)
5900 for (info
->num_regsets
= 0;
5901 info
->regsets
[info
->num_regsets
].size
>= 0;
5902 info
->num_regsets
++)
5908 initialize_low (void)
5910 struct sigaction sigchld_action
;
5911 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
5912 set_target_ops (&linux_target_ops
);
5913 set_breakpoint_data (the_low_target
.breakpoint
,
5914 the_low_target
.breakpoint_len
);
5915 linux_init_signals ();
5916 linux_ptrace_init_warnings ();
5918 sigchld_action
.sa_handler
= sigchld_handler
;
5919 sigemptyset (&sigchld_action
.sa_mask
);
5920 sigchld_action
.sa_flags
= SA_RESTART
;
5921 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
5923 initialize_low_arch ();