1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2016 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 "nat/linux-osdata.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
29 #include "nat/gdb_ptrace.h"
30 #include "nat/linux-ptrace.h"
31 #include "nat/linux-procfs.h"
32 #include "nat/linux-personality.h"
34 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
46 #include "filestuff.h"
47 #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. */
57 #include "nat/linux-namespaces.h"
60 #define SPUFS_MAGIC 0x23c9b64e
63 #ifdef HAVE_PERSONALITY
64 # include <sys/personality.h>
65 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
66 # define ADDR_NO_RANDOMIZE 0x0040000
74 /* Some targets did not define these ptrace constants from the start,
75 so gdbserver defines them locally here. In the future, these may
76 be removed after they are added to asm/ptrace.h. */
77 #if !(defined(PT_TEXT_ADDR) \
78 || defined(PT_DATA_ADDR) \
79 || defined(PT_TEXT_END_ADDR))
80 #if defined(__mcoldfire__)
81 /* These are still undefined in 3.10 kernels. */
82 #define PT_TEXT_ADDR 49*4
83 #define PT_DATA_ADDR 50*4
84 #define PT_TEXT_END_ADDR 51*4
85 /* BFIN already defines these since at least 2.6.32 kernels. */
87 #define PT_TEXT_ADDR 220
88 #define PT_TEXT_END_ADDR 224
89 #define PT_DATA_ADDR 228
90 /* These are still undefined in 3.10 kernels. */
91 #elif defined(__TMS320C6X__)
92 #define PT_TEXT_ADDR (0x10000*4)
93 #define PT_DATA_ADDR (0x10004*4)
94 #define PT_TEXT_END_ADDR (0x10008*4)
98 #ifdef HAVE_LINUX_BTRACE
99 # include "nat/linux-btrace.h"
100 # include "btrace-common.h"
103 #ifndef HAVE_ELF32_AUXV_T
104 /* Copied from glibc's elf.h. */
107 uint32_t a_type
; /* Entry type */
110 uint32_t a_val
; /* Integer value */
111 /* We use to have pointer elements added here. We cannot do that,
112 though, since it does not work when using 32-bit definitions
113 on 64-bit platforms and vice versa. */
118 #ifndef HAVE_ELF64_AUXV_T
119 /* Copied from glibc's elf.h. */
122 uint64_t a_type
; /* Entry type */
125 uint64_t a_val
; /* Integer value */
126 /* We use to have pointer elements added here. We cannot do that,
127 though, since it does not work when using 32-bit definitions
128 on 64-bit platforms and vice versa. */
133 /* Does the current host support PTRACE_GETREGSET? */
134 int have_ptrace_getregset
= -1;
138 /* See nat/linux-nat.h. */
141 ptid_of_lwp (struct lwp_info
*lwp
)
143 return ptid_of (get_lwp_thread (lwp
));
146 /* See nat/linux-nat.h. */
149 lwp_set_arch_private_info (struct lwp_info
*lwp
,
150 struct arch_lwp_info
*info
)
152 lwp
->arch_private
= info
;
155 /* See nat/linux-nat.h. */
157 struct arch_lwp_info
*
158 lwp_arch_private_info (struct lwp_info
*lwp
)
160 return lwp
->arch_private
;
163 /* See nat/linux-nat.h. */
166 lwp_is_stopped (struct lwp_info
*lwp
)
171 /* See nat/linux-nat.h. */
173 enum target_stop_reason
174 lwp_stop_reason (struct lwp_info
*lwp
)
176 return lwp
->stop_reason
;
179 /* A list of all unknown processes which receive stop signals. Some
180 other process will presumably claim each of these as forked
181 children momentarily. */
183 struct simple_pid_list
185 /* The process ID. */
188 /* The status as reported by waitpid. */
192 struct simple_pid_list
*next
;
194 struct simple_pid_list
*stopped_pids
;
196 /* Trivial list manipulation functions to keep track of a list of new
197 stopped processes. */
200 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
202 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
205 new_pid
->status
= status
;
206 new_pid
->next
= *listp
;
211 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
213 struct simple_pid_list
**p
;
215 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
216 if ((*p
)->pid
== pid
)
218 struct simple_pid_list
*next
= (*p
)->next
;
220 *statusp
= (*p
)->status
;
228 enum stopping_threads_kind
230 /* Not stopping threads presently. */
231 NOT_STOPPING_THREADS
,
233 /* Stopping threads. */
236 /* Stopping and suspending threads. */
237 STOPPING_AND_SUSPENDING_THREADS
240 /* This is set while stop_all_lwps is in effect. */
241 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
243 /* FIXME make into a target method? */
244 int using_threads
= 1;
246 /* True if we're presently stabilizing threads (moving them out of
248 static int stabilizing_threads
;
250 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
251 int step
, int signal
, siginfo_t
*info
);
252 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
253 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
254 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
255 static int linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
256 int *wstat
, int options
);
257 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
258 static struct lwp_info
*add_lwp (ptid_t ptid
);
259 static void linux_mourn (struct process_info
*process
);
260 static int linux_stopped_by_watchpoint (void);
261 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
262 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
263 static void proceed_all_lwps (void);
264 static int finish_step_over (struct lwp_info
*lwp
);
265 static int kill_lwp (unsigned long lwpid
, int signo
);
266 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
267 static void complete_ongoing_step_over (void);
268 static int linux_low_ptrace_options (int attached
);
270 /* When the event-loop is doing a step-over, this points at the thread
272 ptid_t step_over_bkpt
;
274 /* True if the low target can hardware single-step. */
277 can_hardware_single_step (void)
279 if (the_low_target
.supports_hardware_single_step
!= NULL
)
280 return the_low_target
.supports_hardware_single_step ();
285 /* True if the low target can software single-step. Such targets
286 implement the GET_NEXT_PCS callback. */
289 can_software_single_step (void)
291 return (the_low_target
.get_next_pcs
!= NULL
);
294 /* True if the low target supports memory breakpoints. If so, we'll
295 have a GET_PC implementation. */
298 supports_breakpoints (void)
300 return (the_low_target
.get_pc
!= NULL
);
303 /* Returns true if this target can support fast tracepoints. This
304 does not mean that the in-process agent has been loaded in the
308 supports_fast_tracepoints (void)
310 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
313 /* True if LWP is stopped in its stepping range. */
316 lwp_in_step_range (struct lwp_info
*lwp
)
318 CORE_ADDR pc
= lwp
->stop_pc
;
320 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
323 struct pending_signals
327 struct pending_signals
*prev
;
330 /* The read/write ends of the pipe registered as waitable file in the
332 static int linux_event_pipe
[2] = { -1, -1 };
334 /* True if we're currently in async mode. */
335 #define target_is_async_p() (linux_event_pipe[0] != -1)
337 static void send_sigstop (struct lwp_info
*lwp
);
338 static void wait_for_sigstop (void);
340 /* Return non-zero if HEADER is a 64-bit ELF file. */
343 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
345 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
346 && header
->e_ident
[EI_MAG1
] == ELFMAG1
347 && header
->e_ident
[EI_MAG2
] == ELFMAG2
348 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
350 *machine
= header
->e_machine
;
351 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
358 /* Return non-zero if FILE is a 64-bit ELF file,
359 zero if the file is not a 64-bit ELF file,
360 and -1 if the file is not accessible or doesn't exist. */
363 elf_64_file_p (const char *file
, unsigned int *machine
)
368 fd
= open (file
, O_RDONLY
);
372 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
379 return elf_64_header_p (&header
, machine
);
382 /* Accepts an integer PID; Returns true if the executable PID is
383 running is a 64-bit ELF file.. */
386 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
390 sprintf (file
, "/proc/%d/exe", pid
);
391 return elf_64_file_p (file
, machine
);
395 delete_lwp (struct lwp_info
*lwp
)
397 struct thread_info
*thr
= get_lwp_thread (lwp
);
400 debug_printf ("deleting %ld\n", lwpid_of (thr
));
403 free (lwp
->arch_private
);
407 /* Add a process to the common process list, and set its private
410 static struct process_info
*
411 linux_add_process (int pid
, int attached
)
413 struct process_info
*proc
;
415 proc
= add_process (pid
, attached
);
416 proc
->priv
= XCNEW (struct process_info_private
);
418 if (the_low_target
.new_process
!= NULL
)
419 proc
->priv
->arch_private
= the_low_target
.new_process ();
424 static CORE_ADDR
get_pc (struct lwp_info
*lwp
);
426 /* Call the target arch_setup function on the current thread. */
429 linux_arch_setup (void)
431 the_low_target
.arch_setup ();
434 /* Call the target arch_setup function on THREAD. */
437 linux_arch_setup_thread (struct thread_info
*thread
)
439 struct thread_info
*saved_thread
;
441 saved_thread
= current_thread
;
442 current_thread
= thread
;
446 current_thread
= saved_thread
;
449 /* Handle a GNU/Linux extended wait response. If we see a clone,
450 fork, or vfork event, we need to add the new LWP to our list
451 (and return 0 so as not to report the trap to higher layers).
452 If we see an exec event, we will modify ORIG_EVENT_LWP to point
453 to a new LWP representing the new program. */
456 handle_extended_wait (struct lwp_info
**orig_event_lwp
, int wstat
)
458 struct lwp_info
*event_lwp
= *orig_event_lwp
;
459 int event
= linux_ptrace_get_extended_event (wstat
);
460 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
461 struct lwp_info
*new_lwp
;
463 gdb_assert (event_lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
465 /* All extended events we currently use are mid-syscall. Only
466 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
467 you have to be using PTRACE_SEIZE to get that. */
468 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
470 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
471 || (event
== PTRACE_EVENT_CLONE
))
474 unsigned long new_pid
;
477 /* Get the pid of the new lwp. */
478 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
481 /* If we haven't already seen the new PID stop, wait for it now. */
482 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
484 /* The new child has a pending SIGSTOP. We can't affect it until it
485 hits the SIGSTOP, but we're already attached. */
487 ret
= my_waitpid (new_pid
, &status
, __WALL
);
490 perror_with_name ("waiting for new child");
491 else if (ret
!= new_pid
)
492 warning ("wait returned unexpected PID %d", ret
);
493 else if (!WIFSTOPPED (status
))
494 warning ("wait returned unexpected status 0x%x", status
);
497 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
499 struct process_info
*parent_proc
;
500 struct process_info
*child_proc
;
501 struct lwp_info
*child_lwp
;
502 struct thread_info
*child_thr
;
503 struct target_desc
*tdesc
;
505 ptid
= ptid_build (new_pid
, new_pid
, 0);
509 debug_printf ("HEW: Got fork event from LWP %ld, "
511 ptid_get_lwp (ptid_of (event_thr
)),
512 ptid_get_pid (ptid
));
515 /* Add the new process to the tables and clone the breakpoint
516 lists of the parent. We need to do this even if the new process
517 will be detached, since we will need the process object and the
518 breakpoints to remove any breakpoints from memory when we
519 detach, and the client side will access registers. */
520 child_proc
= linux_add_process (new_pid
, 0);
521 gdb_assert (child_proc
!= NULL
);
522 child_lwp
= add_lwp (ptid
);
523 gdb_assert (child_lwp
!= NULL
);
524 child_lwp
->stopped
= 1;
525 child_lwp
->must_set_ptrace_flags
= 1;
526 child_lwp
->status_pending_p
= 0;
527 child_thr
= get_lwp_thread (child_lwp
);
528 child_thr
->last_resume_kind
= resume_stop
;
529 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
531 /* If we're suspending all threads, leave this one suspended
533 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
536 debug_printf ("HEW: leaving child suspended\n");
537 child_lwp
->suspended
= 1;
540 parent_proc
= get_thread_process (event_thr
);
541 child_proc
->attached
= parent_proc
->attached
;
542 clone_all_breakpoints (&child_proc
->breakpoints
,
543 &child_proc
->raw_breakpoints
,
544 parent_proc
->breakpoints
);
546 tdesc
= XNEW (struct target_desc
);
547 copy_target_description (tdesc
, parent_proc
->tdesc
);
548 child_proc
->tdesc
= tdesc
;
550 /* Clone arch-specific process data. */
551 if (the_low_target
.new_fork
!= NULL
)
552 the_low_target
.new_fork (parent_proc
, child_proc
);
554 /* Save fork info in the parent thread. */
555 if (event
== PTRACE_EVENT_FORK
)
556 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
557 else if (event
== PTRACE_EVENT_VFORK
)
558 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
560 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
562 /* The status_pending field contains bits denoting the
563 extended event, so when the pending event is handled,
564 the handler will look at lwp->waitstatus. */
565 event_lwp
->status_pending_p
= 1;
566 event_lwp
->status_pending
= wstat
;
568 /* Report the event. */
573 debug_printf ("HEW: Got clone event "
574 "from LWP %ld, new child is LWP %ld\n",
575 lwpid_of (event_thr
), new_pid
);
577 ptid
= ptid_build (pid_of (event_thr
), new_pid
, 0);
578 new_lwp
= add_lwp (ptid
);
580 /* Either we're going to immediately resume the new thread
581 or leave it stopped. linux_resume_one_lwp is a nop if it
582 thinks the thread is currently running, so set this first
583 before calling linux_resume_one_lwp. */
584 new_lwp
->stopped
= 1;
586 /* If we're suspending all threads, leave this one suspended
588 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
589 new_lwp
->suspended
= 1;
591 /* Normally we will get the pending SIGSTOP. But in some cases
592 we might get another signal delivered to the group first.
593 If we do get another signal, be sure not to lose it. */
594 if (WSTOPSIG (status
) != SIGSTOP
)
596 new_lwp
->stop_expected
= 1;
597 new_lwp
->status_pending_p
= 1;
598 new_lwp
->status_pending
= status
;
600 else if (report_thread_events
)
602 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
603 new_lwp
->status_pending_p
= 1;
604 new_lwp
->status_pending
= status
;
607 /* Don't report the event. */
610 else if (event
== PTRACE_EVENT_VFORK_DONE
)
612 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
614 /* Report the event. */
617 else if (event
== PTRACE_EVENT_EXEC
&& report_exec_events
)
619 struct process_info
*proc
;
620 VEC (int) *syscalls_to_catch
;
626 debug_printf ("HEW: Got exec event from LWP %ld\n",
627 lwpid_of (event_thr
));
630 /* Get the event ptid. */
631 event_ptid
= ptid_of (event_thr
);
632 event_pid
= ptid_get_pid (event_ptid
);
634 /* Save the syscall list from the execing process. */
635 proc
= get_thread_process (event_thr
);
636 syscalls_to_catch
= proc
->syscalls_to_catch
;
637 proc
->syscalls_to_catch
= NULL
;
639 /* Delete the execing process and all its threads. */
641 current_thread
= NULL
;
643 /* Create a new process/lwp/thread. */
644 proc
= linux_add_process (event_pid
, 0);
645 event_lwp
= add_lwp (event_ptid
);
646 event_thr
= get_lwp_thread (event_lwp
);
647 gdb_assert (current_thread
== event_thr
);
648 linux_arch_setup_thread (event_thr
);
650 /* Set the event status. */
651 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
652 event_lwp
->waitstatus
.value
.execd_pathname
653 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
655 /* Mark the exec status as pending. */
656 event_lwp
->stopped
= 1;
657 event_lwp
->status_pending_p
= 1;
658 event_lwp
->status_pending
= wstat
;
659 event_thr
->last_resume_kind
= resume_continue
;
660 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
662 /* Update syscall state in the new lwp, effectively mid-syscall too. */
663 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
665 /* Restore the list to catch. Don't rely on the client, which is free
666 to avoid sending a new list when the architecture doesn't change.
667 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
668 proc
->syscalls_to_catch
= syscalls_to_catch
;
670 /* Report the event. */
671 *orig_event_lwp
= event_lwp
;
675 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
678 /* Return the PC as read from the regcache of LWP, without any
682 get_pc (struct lwp_info
*lwp
)
684 struct thread_info
*saved_thread
;
685 struct regcache
*regcache
;
688 if (the_low_target
.get_pc
== NULL
)
691 saved_thread
= current_thread
;
692 current_thread
= get_lwp_thread (lwp
);
694 regcache
= get_thread_regcache (current_thread
, 1);
695 pc
= (*the_low_target
.get_pc
) (regcache
);
698 debug_printf ("pc is 0x%lx\n", (long) pc
);
700 current_thread
= saved_thread
;
704 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
705 Fill *SYSNO with the syscall nr trapped. Fill *SYSRET with the
709 get_syscall_trapinfo (struct lwp_info
*lwp
, int *sysno
, int *sysret
)
711 struct thread_info
*saved_thread
;
712 struct regcache
*regcache
;
714 if (the_low_target
.get_syscall_trapinfo
== NULL
)
716 /* If we cannot get the syscall trapinfo, report an unknown
717 system call number and -ENOSYS return value. */
718 *sysno
= UNKNOWN_SYSCALL
;
723 saved_thread
= current_thread
;
724 current_thread
= get_lwp_thread (lwp
);
726 regcache
= get_thread_regcache (current_thread
, 1);
727 (*the_low_target
.get_syscall_trapinfo
) (regcache
, sysno
, sysret
);
731 debug_printf ("get_syscall_trapinfo sysno %d sysret %d\n",
735 current_thread
= saved_thread
;
738 /* This function should only be called if LWP got a SIGTRAP.
739 The SIGTRAP could mean several things.
741 On i386, where decr_pc_after_break is non-zero:
743 If we were single-stepping this process using PTRACE_SINGLESTEP, we
744 will get only the one SIGTRAP. The value of $eip will be the next
745 instruction. If the instruction we stepped over was a breakpoint,
746 we need to decrement the PC.
748 If we continue the process using PTRACE_CONT, we will get a
749 SIGTRAP when we hit a breakpoint. The value of $eip will be
750 the instruction after the breakpoint (i.e. needs to be
751 decremented). If we report the SIGTRAP to GDB, we must also
752 report the undecremented PC. If the breakpoint is removed, we
753 must resume at the decremented PC.
755 On a non-decr_pc_after_break machine with hardware or kernel
758 If we either single-step a breakpoint instruction, or continue and
759 hit a breakpoint instruction, our PC will point at the breakpoint
763 check_stopped_by_breakpoint (struct lwp_info
*lwp
)
766 CORE_ADDR sw_breakpoint_pc
;
767 struct thread_info
*saved_thread
;
768 #if USE_SIGTRAP_SIGINFO
772 if (the_low_target
.get_pc
== NULL
)
776 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
778 /* breakpoint_at reads from the current thread. */
779 saved_thread
= current_thread
;
780 current_thread
= get_lwp_thread (lwp
);
782 #if USE_SIGTRAP_SIGINFO
783 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
784 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
786 if (siginfo
.si_signo
== SIGTRAP
)
788 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
792 struct thread_info
*thr
= get_lwp_thread (lwp
);
794 debug_printf ("CSBB: %s stopped by software breakpoint\n",
795 target_pid_to_str (ptid_of (thr
)));
798 /* Back up the PC if necessary. */
799 if (pc
!= sw_breakpoint_pc
)
801 struct regcache
*regcache
802 = get_thread_regcache (current_thread
, 1);
803 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
806 lwp
->stop_pc
= sw_breakpoint_pc
;
807 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
808 current_thread
= saved_thread
;
811 else if (siginfo
.si_code
== TRAP_HWBKPT
)
815 struct thread_info
*thr
= get_lwp_thread (lwp
);
817 debug_printf ("CSBB: %s stopped by hardware "
818 "breakpoint/watchpoint\n",
819 target_pid_to_str (ptid_of (thr
)));
823 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
824 current_thread
= saved_thread
;
827 else if (siginfo
.si_code
== TRAP_TRACE
)
831 struct thread_info
*thr
= get_lwp_thread (lwp
);
833 debug_printf ("CSBB: %s stopped by trace\n",
834 target_pid_to_str (ptid_of (thr
)));
837 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
842 /* We may have just stepped a breakpoint instruction. E.g., in
843 non-stop mode, GDB first tells the thread A to step a range, and
844 then the user inserts a breakpoint inside the range. In that
845 case we need to report the breakpoint PC. */
846 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
847 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
851 struct thread_info
*thr
= get_lwp_thread (lwp
);
853 debug_printf ("CSBB: %s stopped by software breakpoint\n",
854 target_pid_to_str (ptid_of (thr
)));
857 /* Back up the PC if necessary. */
858 if (pc
!= sw_breakpoint_pc
)
860 struct regcache
*regcache
861 = get_thread_regcache (current_thread
, 1);
862 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
865 lwp
->stop_pc
= sw_breakpoint_pc
;
866 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
867 current_thread
= saved_thread
;
871 if (hardware_breakpoint_inserted_here (pc
))
875 struct thread_info
*thr
= get_lwp_thread (lwp
);
877 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
878 target_pid_to_str (ptid_of (thr
)));
882 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
883 current_thread
= saved_thread
;
888 current_thread
= saved_thread
;
892 static struct lwp_info
*
893 add_lwp (ptid_t ptid
)
895 struct lwp_info
*lwp
;
897 lwp
= XCNEW (struct lwp_info
);
899 lwp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
901 if (the_low_target
.new_thread
!= NULL
)
902 the_low_target
.new_thread (lwp
);
904 lwp
->thread
= add_thread (ptid
, lwp
);
909 /* Start an inferior process and returns its pid.
910 ALLARGS is a vector of program-name and args. */
913 linux_create_inferior (char *program
, char **allargs
)
915 struct lwp_info
*new_lwp
;
918 struct cleanup
*restore_personality
919 = maybe_disable_address_space_randomization (disable_randomization
);
921 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
927 perror_with_name ("fork");
932 ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
936 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
937 stdout to stderr so that inferior i/o doesn't corrupt the connection.
938 Also, redirect stdin to /dev/null. */
939 if (remote_connection_is_stdio ())
942 open ("/dev/null", O_RDONLY
);
944 if (write (2, "stdin/stdout redirected\n",
945 sizeof ("stdin/stdout redirected\n") - 1) < 0)
947 /* Errors ignored. */;
951 execv (program
, allargs
);
953 execvp (program
, allargs
);
955 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
961 do_cleanups (restore_personality
);
963 linux_add_process (pid
, 0);
965 ptid
= ptid_build (pid
, pid
, 0);
966 new_lwp
= add_lwp (ptid
);
967 new_lwp
->must_set_ptrace_flags
= 1;
972 /* Implement the post_create_inferior target_ops method. */
975 linux_post_create_inferior (void)
977 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
981 if (lwp
->must_set_ptrace_flags
)
983 struct process_info
*proc
= current_process ();
984 int options
= linux_low_ptrace_options (proc
->attached
);
986 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
987 lwp
->must_set_ptrace_flags
= 0;
991 /* Attach to an inferior process. Returns 0 on success, ERRNO on
995 linux_attach_lwp (ptid_t ptid
)
997 struct lwp_info
*new_lwp
;
998 int lwpid
= ptid_get_lwp (ptid
);
1000 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
1004 new_lwp
= add_lwp (ptid
);
1006 /* We need to wait for SIGSTOP before being able to make the next
1007 ptrace call on this LWP. */
1008 new_lwp
->must_set_ptrace_flags
= 1;
1010 if (linux_proc_pid_is_stopped (lwpid
))
1013 debug_printf ("Attached to a stopped process\n");
1015 /* The process is definitely stopped. It is in a job control
1016 stop, unless the kernel predates the TASK_STOPPED /
1017 TASK_TRACED distinction, in which case it might be in a
1018 ptrace stop. Make sure it is in a ptrace stop; from there we
1019 can kill it, signal it, et cetera.
1021 First make sure there is a pending SIGSTOP. Since we are
1022 already attached, the process can not transition from stopped
1023 to running without a PTRACE_CONT; so we know this signal will
1024 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1025 probably already in the queue (unless this kernel is old
1026 enough to use TASK_STOPPED for ptrace stops); but since
1027 SIGSTOP is not an RT signal, it can only be queued once. */
1028 kill_lwp (lwpid
, SIGSTOP
);
1030 /* Finally, resume the stopped process. This will deliver the
1031 SIGSTOP (or a higher priority signal, just like normal
1032 PTRACE_ATTACH), which we'll catch later on. */
1033 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1036 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1037 brings it to a halt.
1039 There are several cases to consider here:
1041 1) gdbserver has already attached to the process and is being notified
1042 of a new thread that is being created.
1043 In this case we should ignore that SIGSTOP and resume the
1044 process. This is handled below by setting stop_expected = 1,
1045 and the fact that add_thread sets last_resume_kind ==
1048 2) This is the first thread (the process thread), and we're attaching
1049 to it via attach_inferior.
1050 In this case we want the process thread to stop.
1051 This is handled by having linux_attach set last_resume_kind ==
1052 resume_stop after we return.
1054 If the pid we are attaching to is also the tgid, we attach to and
1055 stop all the existing threads. Otherwise, we attach to pid and
1056 ignore any other threads in the same group as this pid.
1058 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1060 In this case we want the thread to stop.
1061 FIXME: This case is currently not properly handled.
1062 We should wait for the SIGSTOP but don't. Things work apparently
1063 because enough time passes between when we ptrace (ATTACH) and when
1064 gdb makes the next ptrace call on the thread.
1066 On the other hand, if we are currently trying to stop all threads, we
1067 should treat the new thread as if we had sent it a SIGSTOP. This works
1068 because we are guaranteed that the add_lwp call above added us to the
1069 end of the list, and so the new thread has not yet reached
1070 wait_for_sigstop (but will). */
1071 new_lwp
->stop_expected
= 1;
1076 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1077 already attached. Returns true if a new LWP is found, false
1081 attach_proc_task_lwp_callback (ptid_t ptid
)
1083 /* Is this a new thread? */
1084 if (find_thread_ptid (ptid
) == NULL
)
1086 int lwpid
= ptid_get_lwp (ptid
);
1090 debug_printf ("Found new lwp %d\n", lwpid
);
1092 err
= linux_attach_lwp (ptid
);
1094 /* Be quiet if we simply raced with the thread exiting. EPERM
1095 is returned if the thread's task still exists, and is marked
1096 as exited or zombie, as well as other conditions, so in that
1097 case, confirm the status in /proc/PID/status. */
1099 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1103 debug_printf ("Cannot attach to lwp %d: "
1104 "thread is gone (%d: %s)\n",
1105 lwpid
, err
, strerror (err
));
1110 warning (_("Cannot attach to lwp %d: %s"),
1112 linux_ptrace_attach_fail_reason_string (ptid
, err
));
1120 static void async_file_mark (void);
1122 /* Attach to PID. If PID is the tgid, attach to it and all
1126 linux_attach (unsigned long pid
)
1128 struct process_info
*proc
;
1129 struct thread_info
*initial_thread
;
1130 ptid_t ptid
= ptid_build (pid
, pid
, 0);
1133 /* Attach to PID. We will check for other threads
1135 err
= linux_attach_lwp (ptid
);
1137 error ("Cannot attach to process %ld: %s",
1138 pid
, linux_ptrace_attach_fail_reason_string (ptid
, err
));
1140 proc
= linux_add_process (pid
, 1);
1142 /* Don't ignore the initial SIGSTOP if we just attached to this
1143 process. It will be collected by wait shortly. */
1144 initial_thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
1145 initial_thread
->last_resume_kind
= resume_stop
;
1147 /* We must attach to every LWP. If /proc is mounted, use that to
1148 find them now. On the one hand, the inferior may be using raw
1149 clone instead of using pthreads. On the other hand, even if it
1150 is using pthreads, GDB may not be connected yet (thread_db needs
1151 to do symbol lookups, through qSymbol). Also, thread_db walks
1152 structures in the inferior's address space to find the list of
1153 threads/LWPs, and those structures may well be corrupted. Note
1154 that once thread_db is loaded, we'll still use it to list threads
1155 and associate pthread info with each LWP. */
1156 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1158 /* GDB will shortly read the xml target description for this
1159 process, to figure out the process' architecture. But the target
1160 description is only filled in when the first process/thread in
1161 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1162 that now, otherwise, if GDB is fast enough, it could read the
1163 target description _before_ that initial stop. */
1166 struct lwp_info
*lwp
;
1168 ptid_t pid_ptid
= pid_to_ptid (pid
);
1170 lwpid
= linux_wait_for_event_filtered (pid_ptid
, pid_ptid
,
1172 gdb_assert (lwpid
> 0);
1174 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
1176 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1178 lwp
->status_pending_p
= 1;
1179 lwp
->status_pending
= wstat
;
1182 initial_thread
->last_resume_kind
= resume_continue
;
1186 gdb_assert (proc
->tdesc
!= NULL
);
1199 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
1201 struct counter
*counter
= (struct counter
*) args
;
1203 if (ptid_get_pid (entry
->id
) == counter
->pid
)
1205 if (++counter
->count
> 1)
1213 last_thread_of_process_p (int pid
)
1215 struct counter counter
= { pid
, 0 };
1217 return (find_inferior (&all_threads
,
1218 second_thread_of_pid_p
, &counter
) == NULL
);
1224 linux_kill_one_lwp (struct lwp_info
*lwp
)
1226 struct thread_info
*thr
= get_lwp_thread (lwp
);
1227 int pid
= lwpid_of (thr
);
1229 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1230 there is no signal context, and ptrace(PTRACE_KILL) (or
1231 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1232 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1233 alternative is to kill with SIGKILL. We only need one SIGKILL
1234 per process, not one for each thread. But since we still support
1235 support debugging programs using raw clone without CLONE_THREAD,
1236 we send one for each thread. For years, we used PTRACE_KILL
1237 only, so we're being a bit paranoid about some old kernels where
1238 PTRACE_KILL might work better (dubious if there are any such, but
1239 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1240 second, and so we're fine everywhere. */
1243 kill_lwp (pid
, SIGKILL
);
1246 int save_errno
= errno
;
1248 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1249 target_pid_to_str (ptid_of (thr
)),
1250 save_errno
? strerror (save_errno
) : "OK");
1254 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1257 int save_errno
= errno
;
1259 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1260 target_pid_to_str (ptid_of (thr
)),
1261 save_errno
? strerror (save_errno
) : "OK");
1265 /* Kill LWP and wait for it to die. */
1268 kill_wait_lwp (struct lwp_info
*lwp
)
1270 struct thread_info
*thr
= get_lwp_thread (lwp
);
1271 int pid
= ptid_get_pid (ptid_of (thr
));
1272 int lwpid
= ptid_get_lwp (ptid_of (thr
));
1277 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1281 linux_kill_one_lwp (lwp
);
1283 /* Make sure it died. Notes:
1285 - The loop is most likely unnecessary.
1287 - We don't use linux_wait_for_event as that could delete lwps
1288 while we're iterating over them. We're not interested in
1289 any pending status at this point, only in making sure all
1290 wait status on the kernel side are collected until the
1293 - We don't use __WALL here as the __WALL emulation relies on
1294 SIGCHLD, and killing a stopped process doesn't generate
1295 one, nor an exit status.
1297 res
= my_waitpid (lwpid
, &wstat
, 0);
1298 if (res
== -1 && errno
== ECHILD
)
1299 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1300 } while (res
> 0 && WIFSTOPPED (wstat
));
1302 /* Even if it was stopped, the child may have already disappeared.
1303 E.g., if it was killed by SIGKILL. */
1304 if (res
< 0 && errno
!= ECHILD
)
1305 perror_with_name ("kill_wait_lwp");
1308 /* Callback for `find_inferior'. Kills an lwp of a given process,
1309 except the leader. */
1312 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
1314 struct thread_info
*thread
= (struct thread_info
*) entry
;
1315 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1316 int pid
= * (int *) args
;
1318 if (ptid_get_pid (entry
->id
) != pid
)
1321 /* We avoid killing the first thread here, because of a Linux kernel (at
1322 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1323 the children get a chance to be reaped, it will remain a zombie
1326 if (lwpid_of (thread
) == pid
)
1329 debug_printf ("lkop: is last of process %s\n",
1330 target_pid_to_str (entry
->id
));
1334 kill_wait_lwp (lwp
);
1339 linux_kill (int pid
)
1341 struct process_info
*process
;
1342 struct lwp_info
*lwp
;
1344 process
= find_process_pid (pid
);
1345 if (process
== NULL
)
1348 /* If we're killing a running inferior, make sure it is stopped
1349 first, as PTRACE_KILL will not work otherwise. */
1350 stop_all_lwps (0, NULL
);
1352 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1354 /* See the comment in linux_kill_one_lwp. We did not kill the first
1355 thread in the list, so do so now. */
1356 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1361 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1365 kill_wait_lwp (lwp
);
1367 the_target
->mourn (process
);
1369 /* Since we presently can only stop all lwps of all processes, we
1370 need to unstop lwps of other processes. */
1371 unstop_all_lwps (0, NULL
);
1375 /* Get pending signal of THREAD, for detaching purposes. This is the
1376 signal the thread last stopped for, which we need to deliver to the
1377 thread when detaching, otherwise, it'd be suppressed/lost. */
1380 get_detach_signal (struct thread_info
*thread
)
1382 enum gdb_signal signo
= GDB_SIGNAL_0
;
1384 struct lwp_info
*lp
= get_thread_lwp (thread
);
1386 if (lp
->status_pending_p
)
1387 status
= lp
->status_pending
;
1390 /* If the thread had been suspended by gdbserver, and it stopped
1391 cleanly, then it'll have stopped with SIGSTOP. But we don't
1392 want to deliver that SIGSTOP. */
1393 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1394 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1397 /* Otherwise, we may need to deliver the signal we
1399 status
= lp
->last_status
;
1402 if (!WIFSTOPPED (status
))
1405 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1406 target_pid_to_str (ptid_of (thread
)));
1410 /* Extended wait statuses aren't real SIGTRAPs. */
1411 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1414 debug_printf ("GPS: lwp %s had stopped with extended "
1415 "status: no pending signal\n",
1416 target_pid_to_str (ptid_of (thread
)));
1420 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1422 if (program_signals_p
&& !program_signals
[signo
])
1425 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1426 target_pid_to_str (ptid_of (thread
)),
1427 gdb_signal_to_string (signo
));
1430 else if (!program_signals_p
1431 /* If we have no way to know which signals GDB does not
1432 want to have passed to the program, assume
1433 SIGTRAP/SIGINT, which is GDB's default. */
1434 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1437 debug_printf ("GPS: lwp %s had signal %s, "
1438 "but we don't know if we should pass it. "
1439 "Default to not.\n",
1440 target_pid_to_str (ptid_of (thread
)),
1441 gdb_signal_to_string (signo
));
1447 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1448 target_pid_to_str (ptid_of (thread
)),
1449 gdb_signal_to_string (signo
));
1451 return WSTOPSIG (status
);
1456 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1458 struct thread_info
*thread
= (struct thread_info
*) entry
;
1459 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1460 int pid
= * (int *) args
;
1463 if (ptid_get_pid (entry
->id
) != pid
)
1466 /* If there is a pending SIGSTOP, get rid of it. */
1467 if (lwp
->stop_expected
)
1470 debug_printf ("Sending SIGCONT to %s\n",
1471 target_pid_to_str (ptid_of (thread
)));
1473 kill_lwp (lwpid_of (thread
), SIGCONT
);
1474 lwp
->stop_expected
= 0;
1477 /* Flush any pending changes to the process's registers. */
1478 regcache_invalidate_thread (thread
);
1480 /* Pass on any pending signal for this thread. */
1481 sig
= get_detach_signal (thread
);
1483 /* Finally, let it resume. */
1484 if (the_low_target
.prepare_to_resume
!= NULL
)
1485 the_low_target
.prepare_to_resume (lwp
);
1486 if (ptrace (PTRACE_DETACH
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1487 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1488 error (_("Can't detach %s: %s"),
1489 target_pid_to_str (ptid_of (thread
)),
1497 linux_detach (int pid
)
1499 struct process_info
*process
;
1501 process
= find_process_pid (pid
);
1502 if (process
== NULL
)
1505 /* As there's a step over already in progress, let it finish first,
1506 otherwise nesting a stabilize_threads operation on top gets real
1508 complete_ongoing_step_over ();
1510 /* Stop all threads before detaching. First, ptrace requires that
1511 the thread is stopped to sucessfully detach. Second, thread_db
1512 may need to uninstall thread event breakpoints from memory, which
1513 only works with a stopped process anyway. */
1514 stop_all_lwps (0, NULL
);
1516 #ifdef USE_THREAD_DB
1517 thread_db_detach (process
);
1520 /* Stabilize threads (move out of jump pads). */
1521 stabilize_threads ();
1523 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1525 the_target
->mourn (process
);
1527 /* Since we presently can only stop all lwps of all processes, we
1528 need to unstop lwps of other processes. */
1529 unstop_all_lwps (0, NULL
);
1533 /* Remove all LWPs that belong to process PROC from the lwp list. */
1536 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1538 struct thread_info
*thread
= (struct thread_info
*) entry
;
1539 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1540 struct process_info
*process
= (struct process_info
*) proc
;
1542 if (pid_of (thread
) == pid_of (process
))
1549 linux_mourn (struct process_info
*process
)
1551 struct process_info_private
*priv
;
1553 #ifdef USE_THREAD_DB
1554 thread_db_mourn (process
);
1557 find_inferior (&all_threads
, delete_lwp_callback
, process
);
1559 /* Freeing all private data. */
1560 priv
= process
->priv
;
1561 free (priv
->arch_private
);
1563 process
->priv
= NULL
;
1565 remove_process (process
);
1569 linux_join (int pid
)
1574 ret
= my_waitpid (pid
, &status
, 0);
1575 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1577 } while (ret
!= -1 || errno
!= ECHILD
);
1580 /* Return nonzero if the given thread is still alive. */
1582 linux_thread_alive (ptid_t ptid
)
1584 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1586 /* We assume we always know if a thread exits. If a whole process
1587 exited but we still haven't been able to report it to GDB, we'll
1588 hold on to the last lwp of the dead process. */
1590 return !lwp_is_marked_dead (lwp
);
1595 /* Return 1 if this lwp still has an interesting status pending. If
1596 not (e.g., it had stopped for a breakpoint that is gone), return
1600 thread_still_has_status_pending_p (struct thread_info
*thread
)
1602 struct lwp_info
*lp
= get_thread_lwp (thread
);
1604 if (!lp
->status_pending_p
)
1607 if (thread
->last_resume_kind
!= resume_stop
1608 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1609 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1611 struct thread_info
*saved_thread
;
1615 gdb_assert (lp
->last_status
!= 0);
1619 saved_thread
= current_thread
;
1620 current_thread
= thread
;
1622 if (pc
!= lp
->stop_pc
)
1625 debug_printf ("PC of %ld changed\n",
1630 #if !USE_SIGTRAP_SIGINFO
1631 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1632 && !(*the_low_target
.breakpoint_at
) (pc
))
1635 debug_printf ("previous SW breakpoint of %ld gone\n",
1639 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1640 && !hardware_breakpoint_inserted_here (pc
))
1643 debug_printf ("previous HW breakpoint of %ld gone\n",
1649 current_thread
= saved_thread
;
1654 debug_printf ("discarding pending breakpoint status\n");
1655 lp
->status_pending_p
= 0;
1663 /* Returns true if LWP is resumed from the client's perspective. */
1666 lwp_resumed (struct lwp_info
*lwp
)
1668 struct thread_info
*thread
= get_lwp_thread (lwp
);
1670 if (thread
->last_resume_kind
!= resume_stop
)
1673 /* Did gdb send us a `vCont;t', but we haven't reported the
1674 corresponding stop to gdb yet? If so, the thread is still
1675 resumed/running from gdb's perspective. */
1676 if (thread
->last_resume_kind
== resume_stop
1677 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1683 /* Return 1 if this lwp has an interesting status pending. */
1685 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1687 struct thread_info
*thread
= (struct thread_info
*) entry
;
1688 struct lwp_info
*lp
= get_thread_lwp (thread
);
1689 ptid_t ptid
= * (ptid_t
*) arg
;
1691 /* Check if we're only interested in events from a specific process
1692 or a specific LWP. */
1693 if (!ptid_match (ptid_of (thread
), ptid
))
1696 if (!lwp_resumed (lp
))
1699 if (lp
->status_pending_p
1700 && !thread_still_has_status_pending_p (thread
))
1702 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1706 return lp
->status_pending_p
;
1710 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1712 ptid_t ptid
= *(ptid_t
*) data
;
1715 if (ptid_get_lwp (ptid
) != 0)
1716 lwp
= ptid_get_lwp (ptid
);
1718 lwp
= ptid_get_pid (ptid
);
1720 if (ptid_get_lwp (entry
->id
) == lwp
)
1727 find_lwp_pid (ptid_t ptid
)
1729 struct inferior_list_entry
*thread
1730 = find_inferior (&all_threads
, same_lwp
, &ptid
);
1735 return get_thread_lwp ((struct thread_info
*) thread
);
1738 /* Return the number of known LWPs in the tgid given by PID. */
1743 struct inferior_list_entry
*inf
, *tmp
;
1746 ALL_INFERIORS (&all_threads
, inf
, tmp
)
1748 if (ptid_get_pid (inf
->id
) == pid
)
1755 /* The arguments passed to iterate_over_lwps. */
1757 struct iterate_over_lwps_args
1759 /* The FILTER argument passed to iterate_over_lwps. */
1762 /* The CALLBACK argument passed to iterate_over_lwps. */
1763 iterate_over_lwps_ftype
*callback
;
1765 /* The DATA argument passed to iterate_over_lwps. */
1769 /* Callback for find_inferior used by iterate_over_lwps to filter
1770 calls to the callback supplied to that function. Returning a
1771 nonzero value causes find_inferiors to stop iterating and return
1772 the current inferior_list_entry. Returning zero indicates that
1773 find_inferiors should continue iterating. */
1776 iterate_over_lwps_filter (struct inferior_list_entry
*entry
, void *args_p
)
1778 struct iterate_over_lwps_args
*args
1779 = (struct iterate_over_lwps_args
*) args_p
;
1781 if (ptid_match (entry
->id
, args
->filter
))
1783 struct thread_info
*thr
= (struct thread_info
*) entry
;
1784 struct lwp_info
*lwp
= get_thread_lwp (thr
);
1786 return (*args
->callback
) (lwp
, args
->data
);
1792 /* See nat/linux-nat.h. */
1795 iterate_over_lwps (ptid_t filter
,
1796 iterate_over_lwps_ftype callback
,
1799 struct iterate_over_lwps_args args
= {filter
, callback
, data
};
1800 struct inferior_list_entry
*entry
;
1802 entry
= find_inferior (&all_threads
, iterate_over_lwps_filter
, &args
);
1806 return get_thread_lwp ((struct thread_info
*) entry
);
1809 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1810 their exits until all other threads in the group have exited. */
1813 check_zombie_leaders (void)
1815 struct process_info
*proc
, *tmp
;
1817 ALL_PROCESSES (proc
, tmp
)
1819 pid_t leader_pid
= pid_of (proc
);
1820 struct lwp_info
*leader_lp
;
1822 leader_lp
= find_lwp_pid (pid_to_ptid (leader_pid
));
1825 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1826 "num_lwps=%d, zombie=%d\n",
1827 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1828 linux_proc_pid_is_zombie (leader_pid
));
1830 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1831 /* Check if there are other threads in the group, as we may
1832 have raced with the inferior simply exiting. */
1833 && !last_thread_of_process_p (leader_pid
)
1834 && linux_proc_pid_is_zombie (leader_pid
))
1836 /* A leader zombie can mean one of two things:
1838 - It exited, and there's an exit status pending
1839 available, or only the leader exited (not the whole
1840 program). In the latter case, we can't waitpid the
1841 leader's exit status until all other threads are gone.
1843 - There are 3 or more threads in the group, and a thread
1844 other than the leader exec'd. On an exec, the Linux
1845 kernel destroys all other threads (except the execing
1846 one) in the thread group, and resets the execing thread's
1847 tid to the tgid. No exit notification is sent for the
1848 execing thread -- from the ptracer's perspective, it
1849 appears as though the execing thread just vanishes.
1850 Until we reap all other threads except the leader and the
1851 execing thread, the leader will be zombie, and the
1852 execing thread will be in `D (disc sleep)'. As soon as
1853 all other threads are reaped, the execing thread changes
1854 it's tid to the tgid, and the previous (zombie) leader
1855 vanishes, giving place to the "new" leader. We could try
1856 distinguishing the exit and exec cases, by waiting once
1857 more, and seeing if something comes out, but it doesn't
1858 sound useful. The previous leader _does_ go away, and
1859 we'll re-add the new one once we see the exec event
1860 (which is just the same as what would happen if the
1861 previous leader did exit voluntarily before some other
1866 "CZL: Thread group leader %d zombie "
1867 "(it exited, or another thread execd).\n",
1870 delete_lwp (leader_lp
);
1875 /* Callback for `find_inferior'. Returns the first LWP that is not
1876 stopped. ARG is a PTID filter. */
1879 not_stopped_callback (struct inferior_list_entry
*entry
, void *arg
)
1881 struct thread_info
*thr
= (struct thread_info
*) entry
;
1882 struct lwp_info
*lwp
;
1883 ptid_t filter
= *(ptid_t
*) arg
;
1885 if (!ptid_match (ptid_of (thr
), filter
))
1888 lwp
= get_thread_lwp (thr
);
1895 /* Increment LWP's suspend count. */
1898 lwp_suspended_inc (struct lwp_info
*lwp
)
1902 if (debug_threads
&& lwp
->suspended
> 4)
1904 struct thread_info
*thread
= get_lwp_thread (lwp
);
1906 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1907 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1911 /* Decrement LWP's suspend count. */
1914 lwp_suspended_decr (struct lwp_info
*lwp
)
1918 if (lwp
->suspended
< 0)
1920 struct thread_info
*thread
= get_lwp_thread (lwp
);
1922 internal_error (__FILE__
, __LINE__
,
1923 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1928 /* This function should only be called if the LWP got a SIGTRAP.
1930 Handle any tracepoint steps or hits. Return true if a tracepoint
1931 event was handled, 0 otherwise. */
1934 handle_tracepoints (struct lwp_info
*lwp
)
1936 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1937 int tpoint_related_event
= 0;
1939 gdb_assert (lwp
->suspended
== 0);
1941 /* If this tracepoint hit causes a tracing stop, we'll immediately
1942 uninsert tracepoints. To do this, we temporarily pause all
1943 threads, unpatch away, and then unpause threads. We need to make
1944 sure the unpausing doesn't resume LWP too. */
1945 lwp_suspended_inc (lwp
);
1947 /* And we need to be sure that any all-threads-stopping doesn't try
1948 to move threads out of the jump pads, as it could deadlock the
1949 inferior (LWP could be in the jump pad, maybe even holding the
1952 /* Do any necessary step collect actions. */
1953 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1955 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1957 /* See if we just hit a tracepoint and do its main collect
1959 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1961 lwp_suspended_decr (lwp
);
1963 gdb_assert (lwp
->suspended
== 0);
1964 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1966 if (tpoint_related_event
)
1969 debug_printf ("got a tracepoint event\n");
1976 /* Convenience wrapper. Returns true if LWP is presently collecting a
1980 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1981 struct fast_tpoint_collect_status
*status
)
1983 CORE_ADDR thread_area
;
1984 struct thread_info
*thread
= get_lwp_thread (lwp
);
1986 if (the_low_target
.get_thread_area
== NULL
)
1989 /* Get the thread area address. This is used to recognize which
1990 thread is which when tracing with the in-process agent library.
1991 We don't read anything from the address, and treat it as opaque;
1992 it's the address itself that we assume is unique per-thread. */
1993 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
1996 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1999 /* The reason we resume in the caller, is because we want to be able
2000 to pass lwp->status_pending as WSTAT, and we need to clear
2001 status_pending_p before resuming, otherwise, linux_resume_one_lwp
2002 refuses to resume. */
2005 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
2007 struct thread_info
*saved_thread
;
2009 saved_thread
= current_thread
;
2010 current_thread
= get_lwp_thread (lwp
);
2013 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
2014 && supports_fast_tracepoints ()
2015 && agent_loaded_p ())
2017 struct fast_tpoint_collect_status status
;
2021 debug_printf ("Checking whether LWP %ld needs to move out of the "
2023 lwpid_of (current_thread
));
2025 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
2028 || (WSTOPSIG (*wstat
) != SIGILL
2029 && WSTOPSIG (*wstat
) != SIGFPE
2030 && WSTOPSIG (*wstat
) != SIGSEGV
2031 && WSTOPSIG (*wstat
) != SIGBUS
))
2033 lwp
->collecting_fast_tracepoint
= r
;
2037 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
2039 /* Haven't executed the original instruction yet.
2040 Set breakpoint there, and wait till it's hit,
2041 then single-step until exiting the jump pad. */
2042 lwp
->exit_jump_pad_bkpt
2043 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
2047 debug_printf ("Checking whether LWP %ld needs to move out of "
2048 "the jump pad...it does\n",
2049 lwpid_of (current_thread
));
2050 current_thread
= saved_thread
;
2057 /* If we get a synchronous signal while collecting, *and*
2058 while executing the (relocated) original instruction,
2059 reset the PC to point at the tpoint address, before
2060 reporting to GDB. Otherwise, it's an IPA lib bug: just
2061 report the signal to GDB, and pray for the best. */
2063 lwp
->collecting_fast_tracepoint
= 0;
2066 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
2067 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2070 struct regcache
*regcache
;
2072 /* The si_addr on a few signals references the address
2073 of the faulting instruction. Adjust that as
2075 if ((WSTOPSIG (*wstat
) == SIGILL
2076 || WSTOPSIG (*wstat
) == SIGFPE
2077 || WSTOPSIG (*wstat
) == SIGBUS
2078 || WSTOPSIG (*wstat
) == SIGSEGV
)
2079 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2080 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2081 /* Final check just to make sure we don't clobber
2082 the siginfo of non-kernel-sent signals. */
2083 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2085 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2086 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2087 (PTRACE_TYPE_ARG3
) 0, &info
);
2090 regcache
= get_thread_regcache (current_thread
, 1);
2091 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
2092 lwp
->stop_pc
= status
.tpoint_addr
;
2094 /* Cancel any fast tracepoint lock this thread was
2096 force_unlock_trace_buffer ();
2099 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2102 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2103 "stopping all threads momentarily.\n");
2105 stop_all_lwps (1, lwp
);
2107 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2108 lwp
->exit_jump_pad_bkpt
= NULL
;
2110 unstop_all_lwps (1, lwp
);
2112 gdb_assert (lwp
->suspended
>= 0);
2118 debug_printf ("Checking whether LWP %ld needs to move out of the "
2120 lwpid_of (current_thread
));
2122 current_thread
= saved_thread
;
2126 /* Enqueue one signal in the "signals to report later when out of the
2130 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2132 struct pending_signals
*p_sig
;
2133 struct thread_info
*thread
= get_lwp_thread (lwp
);
2136 debug_printf ("Deferring signal %d for LWP %ld.\n",
2137 WSTOPSIG (*wstat
), lwpid_of (thread
));
2141 struct pending_signals
*sig
;
2143 for (sig
= lwp
->pending_signals_to_report
;
2146 debug_printf (" Already queued %d\n",
2149 debug_printf (" (no more currently queued signals)\n");
2152 /* Don't enqueue non-RT signals if they are already in the deferred
2153 queue. (SIGSTOP being the easiest signal to see ending up here
2155 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2157 struct pending_signals
*sig
;
2159 for (sig
= lwp
->pending_signals_to_report
;
2163 if (sig
->signal
== WSTOPSIG (*wstat
))
2166 debug_printf ("Not requeuing already queued non-RT signal %d"
2175 p_sig
= XCNEW (struct pending_signals
);
2176 p_sig
->prev
= lwp
->pending_signals_to_report
;
2177 p_sig
->signal
= WSTOPSIG (*wstat
);
2179 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2182 lwp
->pending_signals_to_report
= p_sig
;
2185 /* Dequeue one signal from the "signals to report later when out of
2186 the jump pad" list. */
2189 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2191 struct thread_info
*thread
= get_lwp_thread (lwp
);
2193 if (lwp
->pending_signals_to_report
!= NULL
)
2195 struct pending_signals
**p_sig
;
2197 p_sig
= &lwp
->pending_signals_to_report
;
2198 while ((*p_sig
)->prev
!= NULL
)
2199 p_sig
= &(*p_sig
)->prev
;
2201 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
2202 if ((*p_sig
)->info
.si_signo
!= 0)
2203 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2209 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2210 WSTOPSIG (*wstat
), lwpid_of (thread
));
2214 struct pending_signals
*sig
;
2216 for (sig
= lwp
->pending_signals_to_report
;
2219 debug_printf (" Still queued %d\n",
2222 debug_printf (" (no more queued signals)\n");
2231 /* Fetch the possibly triggered data watchpoint info and store it in
2234 On some archs, like x86, that use debug registers to set
2235 watchpoints, it's possible that the way to know which watched
2236 address trapped, is to check the register that is used to select
2237 which address to watch. Problem is, between setting the watchpoint
2238 and reading back which data address trapped, the user may change
2239 the set of watchpoints, and, as a consequence, GDB changes the
2240 debug registers in the inferior. To avoid reading back a stale
2241 stopped-data-address when that happens, we cache in LP the fact
2242 that a watchpoint trapped, and the corresponding data address, as
2243 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2244 registers meanwhile, we have the cached data we can rely on. */
2247 check_stopped_by_watchpoint (struct lwp_info
*child
)
2249 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2251 struct thread_info
*saved_thread
;
2253 saved_thread
= current_thread
;
2254 current_thread
= get_lwp_thread (child
);
2256 if (the_low_target
.stopped_by_watchpoint ())
2258 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2260 if (the_low_target
.stopped_data_address
!= NULL
)
2261 child
->stopped_data_address
2262 = the_low_target
.stopped_data_address ();
2264 child
->stopped_data_address
= 0;
2267 current_thread
= saved_thread
;
2270 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2273 /* Return the ptrace options that we want to try to enable. */
2276 linux_low_ptrace_options (int attached
)
2281 options
|= PTRACE_O_EXITKILL
;
2283 if (report_fork_events
)
2284 options
|= PTRACE_O_TRACEFORK
;
2286 if (report_vfork_events
)
2287 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2289 if (report_exec_events
)
2290 options
|= PTRACE_O_TRACEEXEC
;
2292 options
|= PTRACE_O_TRACESYSGOOD
;
2297 /* Do low-level handling of the event, and check if we should go on
2298 and pass it to caller code. Return the affected lwp if we are, or
2301 static struct lwp_info
*
2302 linux_low_filter_event (int lwpid
, int wstat
)
2304 struct lwp_info
*child
;
2305 struct thread_info
*thread
;
2306 int have_stop_pc
= 0;
2308 child
= find_lwp_pid (pid_to_ptid (lwpid
));
2310 /* Check for stop events reported by a process we didn't already
2311 know about - anything not already in our LWP list.
2313 If we're expecting to receive stopped processes after
2314 fork, vfork, and clone events, then we'll just add the
2315 new one to our list and go back to waiting for the event
2316 to be reported - the stopped process might be returned
2317 from waitpid before or after the event is.
2319 But note the case of a non-leader thread exec'ing after the
2320 leader having exited, and gone from our lists (because
2321 check_zombie_leaders deleted it). The non-leader thread
2322 changes its tid to the tgid. */
2324 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2325 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2329 /* A multi-thread exec after we had seen the leader exiting. */
2332 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2333 "after exec.\n", lwpid
);
2336 child_ptid
= ptid_build (lwpid
, lwpid
, 0);
2337 child
= add_lwp (child_ptid
);
2339 current_thread
= child
->thread
;
2342 /* If we didn't find a process, one of two things presumably happened:
2343 - A process we started and then detached from has exited. Ignore it.
2344 - A process we are controlling has forked and the new child's stop
2345 was reported to us by the kernel. Save its PID. */
2346 if (child
== NULL
&& WIFSTOPPED (wstat
))
2348 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2351 else if (child
== NULL
)
2354 thread
= get_lwp_thread (child
);
2358 child
->last_status
= wstat
;
2360 /* Check if the thread has exited. */
2361 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2364 debug_printf ("LLFE: %d exited.\n", lwpid
);
2365 /* If there is at least one more LWP, then the exit signal was
2366 not the end of the debugged application and should be
2367 ignored, unless GDB wants to hear about thread exits. */
2368 if (report_thread_events
2369 || last_thread_of_process_p (pid_of (thread
)))
2371 /* Since events are serialized to GDB core, and we can't
2372 report this one right now. Leave the status pending for
2373 the next time we're able to report it. */
2374 mark_lwp_dead (child
, wstat
);
2384 gdb_assert (WIFSTOPPED (wstat
));
2386 if (WIFSTOPPED (wstat
))
2388 struct process_info
*proc
;
2390 /* Architecture-specific setup after inferior is running. */
2391 proc
= find_process_pid (pid_of (thread
));
2392 if (proc
->tdesc
== NULL
)
2396 /* This needs to happen after we have attached to the
2397 inferior and it is stopped for the first time, but
2398 before we access any inferior registers. */
2399 linux_arch_setup_thread (thread
);
2403 /* The process is started, but GDBserver will do
2404 architecture-specific setup after the program stops at
2405 the first instruction. */
2406 child
->status_pending_p
= 1;
2407 child
->status_pending
= wstat
;
2413 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2415 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2416 int options
= linux_low_ptrace_options (proc
->attached
);
2418 linux_enable_event_reporting (lwpid
, options
);
2419 child
->must_set_ptrace_flags
= 0;
2422 /* Always update syscall_state, even if it will be filtered later. */
2423 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SYSCALL_SIGTRAP
)
2425 child
->syscall_state
2426 = (child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2427 ? TARGET_WAITKIND_SYSCALL_RETURN
2428 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2432 /* Almost all other ptrace-stops are known to be outside of system
2433 calls, with further exceptions in handle_extended_wait. */
2434 child
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2437 /* Be careful to not overwrite stop_pc until
2438 check_stopped_by_breakpoint is called. */
2439 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2440 && linux_is_extended_waitstatus (wstat
))
2442 child
->stop_pc
= get_pc (child
);
2443 if (handle_extended_wait (&child
, wstat
))
2445 /* The event has been handled, so just return without
2451 /* Check first whether this was a SW/HW breakpoint before checking
2452 watchpoints, because at least s390 can't tell the data address of
2453 hardware watchpoint hits, and returns stopped-by-watchpoint as
2454 long as there's a watchpoint set. */
2455 if (WIFSTOPPED (wstat
) && linux_wstatus_maybe_breakpoint (wstat
))
2457 if (check_stopped_by_breakpoint (child
))
2461 /* Note that TRAP_HWBKPT can indicate either a hardware breakpoint
2462 or hardware watchpoint. Check which is which if we got
2463 TARGET_STOPPED_BY_HW_BREAKPOINT. Likewise, we may have single
2464 stepped an instruction that triggered a watchpoint. In that
2465 case, on some architectures (such as x86), instead of
2466 TRAP_HWBKPT, si_code indicates TRAP_TRACE, and we need to check
2467 the debug registers separately. */
2468 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2469 && child
->stop_reason
!= TARGET_STOPPED_BY_SW_BREAKPOINT
)
2470 check_stopped_by_watchpoint (child
);
2473 child
->stop_pc
= get_pc (child
);
2475 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2476 && child
->stop_expected
)
2479 debug_printf ("Expected stop.\n");
2480 child
->stop_expected
= 0;
2482 if (thread
->last_resume_kind
== resume_stop
)
2484 /* We want to report the stop to the core. Treat the
2485 SIGSTOP as a normal event. */
2487 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2488 target_pid_to_str (ptid_of (thread
)));
2490 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2492 /* Stopping threads. We don't want this SIGSTOP to end up
2495 debug_printf ("LLW: SIGSTOP caught for %s "
2496 "while stopping threads.\n",
2497 target_pid_to_str (ptid_of (thread
)));
2502 /* This is a delayed SIGSTOP. Filter out the event. */
2504 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2505 child
->stepping
? "step" : "continue",
2506 target_pid_to_str (ptid_of (thread
)));
2508 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2513 child
->status_pending_p
= 1;
2514 child
->status_pending
= wstat
;
2518 /* Resume LWPs that are currently stopped without any pending status
2519 to report, but are resumed from the core's perspective. */
2522 resume_stopped_resumed_lwps (struct inferior_list_entry
*entry
)
2524 struct thread_info
*thread
= (struct thread_info
*) entry
;
2525 struct lwp_info
*lp
= get_thread_lwp (thread
);
2529 && !lp
->status_pending_p
2530 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2532 int step
= thread
->last_resume_kind
== resume_step
;
2535 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2536 target_pid_to_str (ptid_of (thread
)),
2537 paddress (lp
->stop_pc
),
2540 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2544 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2545 match FILTER_PTID (leaving others pending). The PTIDs can be:
2546 minus_one_ptid, to specify any child; a pid PTID, specifying all
2547 lwps of a thread group; or a PTID representing a single lwp. Store
2548 the stop status through the status pointer WSTAT. OPTIONS is
2549 passed to the waitpid call. Return 0 if no event was found and
2550 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2551 was found. Return the PID of the stopped child otherwise. */
2554 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2555 int *wstatp
, int options
)
2557 struct thread_info
*event_thread
;
2558 struct lwp_info
*event_child
, *requested_child
;
2559 sigset_t block_mask
, prev_mask
;
2562 /* N.B. event_thread points to the thread_info struct that contains
2563 event_child. Keep them in sync. */
2564 event_thread
= NULL
;
2566 requested_child
= NULL
;
2568 /* Check for a lwp with a pending status. */
2570 if (ptid_equal (filter_ptid
, minus_one_ptid
) || ptid_is_pid (filter_ptid
))
2572 event_thread
= (struct thread_info
*)
2573 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2574 if (event_thread
!= NULL
)
2575 event_child
= get_thread_lwp (event_thread
);
2576 if (debug_threads
&& event_thread
)
2577 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2579 else if (!ptid_equal (filter_ptid
, null_ptid
))
2581 requested_child
= find_lwp_pid (filter_ptid
);
2583 if (stopping_threads
== NOT_STOPPING_THREADS
2584 && requested_child
->status_pending_p
2585 && requested_child
->collecting_fast_tracepoint
)
2587 enqueue_one_deferred_signal (requested_child
,
2588 &requested_child
->status_pending
);
2589 requested_child
->status_pending_p
= 0;
2590 requested_child
->status_pending
= 0;
2591 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2594 if (requested_child
->suspended
2595 && requested_child
->status_pending_p
)
2597 internal_error (__FILE__
, __LINE__
,
2598 "requesting an event out of a"
2599 " suspended child?");
2602 if (requested_child
->status_pending_p
)
2604 event_child
= requested_child
;
2605 event_thread
= get_lwp_thread (event_child
);
2609 if (event_child
!= NULL
)
2612 debug_printf ("Got an event from pending child %ld (%04x)\n",
2613 lwpid_of (event_thread
), event_child
->status_pending
);
2614 *wstatp
= event_child
->status_pending
;
2615 event_child
->status_pending_p
= 0;
2616 event_child
->status_pending
= 0;
2617 current_thread
= event_thread
;
2618 return lwpid_of (event_thread
);
2621 /* But if we don't find a pending event, we'll have to wait.
2623 We only enter this loop if no process has a pending wait status.
2624 Thus any action taken in response to a wait status inside this
2625 loop is responding as soon as we detect the status, not after any
2628 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2629 all signals while here. */
2630 sigfillset (&block_mask
);
2631 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2633 /* Always pull all events out of the kernel. We'll randomly select
2634 an event LWP out of all that have events, to prevent
2636 while (event_child
== NULL
)
2640 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2643 - If the thread group leader exits while other threads in the
2644 thread group still exist, waitpid(TGID, ...) hangs. That
2645 waitpid won't return an exit status until the other threads
2646 in the group are reaped.
2648 - When a non-leader thread execs, that thread just vanishes
2649 without reporting an exit (so we'd hang if we waited for it
2650 explicitly in that case). The exec event is reported to
2653 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2656 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2657 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2663 debug_printf ("LLW: waitpid %ld received %s\n",
2664 (long) ret
, status_to_str (*wstatp
));
2667 /* Filter all events. IOW, leave all events pending. We'll
2668 randomly select an event LWP out of all that have events
2670 linux_low_filter_event (ret
, *wstatp
);
2671 /* Retry until nothing comes out of waitpid. A single
2672 SIGCHLD can indicate more than one child stopped. */
2676 /* Now that we've pulled all events out of the kernel, resume
2677 LWPs that don't have an interesting event to report. */
2678 if (stopping_threads
== NOT_STOPPING_THREADS
)
2679 for_each_inferior (&all_threads
, resume_stopped_resumed_lwps
);
2681 /* ... and find an LWP with a status to report to the core, if
2683 event_thread
= (struct thread_info
*)
2684 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2685 if (event_thread
!= NULL
)
2687 event_child
= get_thread_lwp (event_thread
);
2688 *wstatp
= event_child
->status_pending
;
2689 event_child
->status_pending_p
= 0;
2690 event_child
->status_pending
= 0;
2694 /* Check for zombie thread group leaders. Those can't be reaped
2695 until all other threads in the thread group are. */
2696 check_zombie_leaders ();
2698 /* If there are no resumed children left in the set of LWPs we
2699 want to wait for, bail. We can't just block in
2700 waitpid/sigsuspend, because lwps might have been left stopped
2701 in trace-stop state, and we'd be stuck forever waiting for
2702 their status to change (which would only happen if we resumed
2703 them). Even if WNOHANG is set, this return code is preferred
2704 over 0 (below), as it is more detailed. */
2705 if ((find_inferior (&all_threads
,
2706 not_stopped_callback
,
2707 &wait_ptid
) == NULL
))
2710 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2711 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2715 /* No interesting event to report to the caller. */
2716 if ((options
& WNOHANG
))
2719 debug_printf ("WNOHANG set, no event found\n");
2721 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2725 /* Block until we get an event reported with SIGCHLD. */
2727 debug_printf ("sigsuspend'ing\n");
2729 sigsuspend (&prev_mask
);
2730 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2734 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2736 current_thread
= event_thread
;
2738 return lwpid_of (event_thread
);
2741 /* Wait for an event from child(ren) PTID. PTIDs can be:
2742 minus_one_ptid, to specify any child; a pid PTID, specifying all
2743 lwps of a thread group; or a PTID representing a single lwp. Store
2744 the stop status through the status pointer WSTAT. OPTIONS is
2745 passed to the waitpid call. Return 0 if no event was found and
2746 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2747 was found. Return the PID of the stopped child otherwise. */
2750 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2752 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2755 /* Count the LWP's that have had events. */
2758 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2760 struct thread_info
*thread
= (struct thread_info
*) entry
;
2761 struct lwp_info
*lp
= get_thread_lwp (thread
);
2762 int *count
= (int *) data
;
2764 gdb_assert (count
!= NULL
);
2766 /* Count only resumed LWPs that have an event pending. */
2767 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2768 && lp
->status_pending_p
)
2774 /* Select the LWP (if any) that is currently being single-stepped. */
2777 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2779 struct thread_info
*thread
= (struct thread_info
*) entry
;
2780 struct lwp_info
*lp
= get_thread_lwp (thread
);
2782 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2783 && thread
->last_resume_kind
== resume_step
2784 && lp
->status_pending_p
)
2790 /* Select the Nth LWP that has had an event. */
2793 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2795 struct thread_info
*thread
= (struct thread_info
*) entry
;
2796 struct lwp_info
*lp
= get_thread_lwp (thread
);
2797 int *selector
= (int *) data
;
2799 gdb_assert (selector
!= NULL
);
2801 /* Select only resumed LWPs that have an event pending. */
2802 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2803 && lp
->status_pending_p
)
2804 if ((*selector
)-- == 0)
2810 /* Select one LWP out of those that have events pending. */
2813 select_event_lwp (struct lwp_info
**orig_lp
)
2816 int random_selector
;
2817 struct thread_info
*event_thread
= NULL
;
2819 /* In all-stop, give preference to the LWP that is being
2820 single-stepped. There will be at most one, and it's the LWP that
2821 the core is most interested in. If we didn't do this, then we'd
2822 have to handle pending step SIGTRAPs somehow in case the core
2823 later continues the previously-stepped thread, otherwise we'd
2824 report the pending SIGTRAP, and the core, not having stepped the
2825 thread, wouldn't understand what the trap was for, and therefore
2826 would report it to the user as a random signal. */
2830 = (struct thread_info
*) find_inferior (&all_threads
,
2831 select_singlestep_lwp_callback
,
2833 if (event_thread
!= NULL
)
2836 debug_printf ("SEL: Select single-step %s\n",
2837 target_pid_to_str (ptid_of (event_thread
)));
2840 if (event_thread
== NULL
)
2842 /* No single-stepping LWP. Select one at random, out of those
2843 which have had events. */
2845 /* First see how many events we have. */
2846 find_inferior (&all_threads
, count_events_callback
, &num_events
);
2847 gdb_assert (num_events
> 0);
2849 /* Now randomly pick a LWP out of those that have had
2851 random_selector
= (int)
2852 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2854 if (debug_threads
&& num_events
> 1)
2855 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2856 num_events
, random_selector
);
2859 = (struct thread_info
*) find_inferior (&all_threads
,
2860 select_event_lwp_callback
,
2864 if (event_thread
!= NULL
)
2866 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2868 /* Switch the event LWP. */
2869 *orig_lp
= event_lp
;
2873 /* Decrement the suspend count of an LWP. */
2876 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2878 struct thread_info
*thread
= (struct thread_info
*) entry
;
2879 struct lwp_info
*lwp
= get_thread_lwp (thread
);
2881 /* Ignore EXCEPT. */
2885 lwp_suspended_decr (lwp
);
2889 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2893 unsuspend_all_lwps (struct lwp_info
*except
)
2895 find_inferior (&all_threads
, unsuspend_one_lwp
, except
);
2898 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2899 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2901 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2902 static ptid_t
linux_wait_1 (ptid_t ptid
,
2903 struct target_waitstatus
*ourstatus
,
2904 int target_options
);
2906 /* Stabilize threads (move out of jump pads).
2908 If a thread is midway collecting a fast tracepoint, we need to
2909 finish the collection and move it out of the jump pad before
2910 reporting the signal.
2912 This avoids recursion while collecting (when a signal arrives
2913 midway, and the signal handler itself collects), which would trash
2914 the trace buffer. In case the user set a breakpoint in a signal
2915 handler, this avoids the backtrace showing the jump pad, etc..
2916 Most importantly, there are certain things we can't do safely if
2917 threads are stopped in a jump pad (or in its callee's). For
2920 - starting a new trace run. A thread still collecting the
2921 previous run, could trash the trace buffer when resumed. The trace
2922 buffer control structures would have been reset but the thread had
2923 no way to tell. The thread could even midway memcpy'ing to the
2924 buffer, which would mean that when resumed, it would clobber the
2925 trace buffer that had been set for a new run.
2927 - we can't rewrite/reuse the jump pads for new tracepoints
2928 safely. Say you do tstart while a thread is stopped midway while
2929 collecting. When the thread is later resumed, it finishes the
2930 collection, and returns to the jump pad, to execute the original
2931 instruction that was under the tracepoint jump at the time the
2932 older run had been started. If the jump pad had been rewritten
2933 since for something else in the new run, the thread would now
2934 execute the wrong / random instructions. */
2937 linux_stabilize_threads (void)
2939 struct thread_info
*saved_thread
;
2940 struct thread_info
*thread_stuck
;
2943 = (struct thread_info
*) find_inferior (&all_threads
,
2944 stuck_in_jump_pad_callback
,
2946 if (thread_stuck
!= NULL
)
2949 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2950 lwpid_of (thread_stuck
));
2954 saved_thread
= current_thread
;
2956 stabilizing_threads
= 1;
2959 for_each_inferior (&all_threads
, move_out_of_jump_pad_callback
);
2961 /* Loop until all are stopped out of the jump pads. */
2962 while (find_inferior (&all_threads
, lwp_running
, NULL
) != NULL
)
2964 struct target_waitstatus ourstatus
;
2965 struct lwp_info
*lwp
;
2968 /* Note that we go through the full wait even loop. While
2969 moving threads out of jump pad, we need to be able to step
2970 over internal breakpoints and such. */
2971 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2973 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2975 lwp
= get_thread_lwp (current_thread
);
2978 lwp_suspended_inc (lwp
);
2980 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2981 || current_thread
->last_resume_kind
== resume_stop
)
2983 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2984 enqueue_one_deferred_signal (lwp
, &wstat
);
2989 find_inferior (&all_threads
, unsuspend_one_lwp
, NULL
);
2991 stabilizing_threads
= 0;
2993 current_thread
= saved_thread
;
2998 = (struct thread_info
*) find_inferior (&all_threads
,
2999 stuck_in_jump_pad_callback
,
3001 if (thread_stuck
!= NULL
)
3002 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
3003 lwpid_of (thread_stuck
));
3007 /* Convenience function that is called when the kernel reports an
3008 event that is not passed out to GDB. */
3011 ignore_event (struct target_waitstatus
*ourstatus
)
3013 /* If we got an event, there may still be others, as a single
3014 SIGCHLD can indicate more than one child stopped. This forces
3015 another target_wait call. */
3018 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3022 /* Convenience function that is called when the kernel reports an exit
3023 event. This decides whether to report the event to GDB as a
3024 process exit event, a thread exit event, or to suppress the
3028 filter_exit_event (struct lwp_info
*event_child
,
3029 struct target_waitstatus
*ourstatus
)
3031 struct thread_info
*thread
= get_lwp_thread (event_child
);
3032 ptid_t ptid
= ptid_of (thread
);
3034 if (!last_thread_of_process_p (pid_of (thread
)))
3036 if (report_thread_events
)
3037 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
3039 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3041 delete_lwp (event_child
);
3046 /* Returns 1 if GDB is interested in any event_child syscalls. */
3049 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
3051 struct thread_info
*thread
= get_lwp_thread (event_child
);
3052 struct process_info
*proc
= get_thread_process (thread
);
3054 return !VEC_empty (int, proc
->syscalls_to_catch
);
3057 /* Returns 1 if GDB is interested in the event_child syscall.
3058 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
3061 gdb_catch_this_syscall_p (struct lwp_info
*event_child
)
3065 struct thread_info
*thread
= get_lwp_thread (event_child
);
3066 struct process_info
*proc
= get_thread_process (thread
);
3068 if (VEC_empty (int, proc
->syscalls_to_catch
))
3071 if (VEC_index (int, proc
->syscalls_to_catch
, 0) == ANY_SYSCALL
)
3074 get_syscall_trapinfo (event_child
, &sysno
, &sysret
);
3076 VEC_iterate (int, proc
->syscalls_to_catch
, i
, iter
);
3084 /* Wait for process, returns status. */
3087 linux_wait_1 (ptid_t ptid
,
3088 struct target_waitstatus
*ourstatus
, int target_options
)
3091 struct lwp_info
*event_child
;
3094 int step_over_finished
;
3095 int bp_explains_trap
;
3096 int maybe_internal_trap
;
3105 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
3108 /* Translate generic target options into linux options. */
3110 if (target_options
& TARGET_WNOHANG
)
3113 bp_explains_trap
= 0;
3116 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3118 /* Find a resumed LWP, if any. */
3119 if (find_inferior (&all_threads
,
3120 status_pending_p_callback
,
3121 &minus_one_ptid
) != NULL
)
3123 else if ((find_inferior (&all_threads
,
3124 not_stopped_callback
,
3125 &minus_one_ptid
) != NULL
))
3130 if (ptid_equal (step_over_bkpt
, null_ptid
))
3131 pid
= linux_wait_for_event (ptid
, &w
, options
);
3135 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3136 target_pid_to_str (step_over_bkpt
));
3137 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
3140 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3142 gdb_assert (target_options
& TARGET_WNOHANG
);
3146 debug_printf ("linux_wait_1 ret = null_ptid, "
3147 "TARGET_WAITKIND_IGNORE\n");
3151 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3158 debug_printf ("linux_wait_1 ret = null_ptid, "
3159 "TARGET_WAITKIND_NO_RESUMED\n");
3163 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3167 event_child
= get_thread_lwp (current_thread
);
3169 /* linux_wait_for_event only returns an exit status for the last
3170 child of a process. Report it. */
3171 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3175 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3176 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3180 debug_printf ("linux_wait_1 ret = %s, exited with "
3182 target_pid_to_str (ptid_of (current_thread
)),
3189 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3190 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3194 debug_printf ("linux_wait_1 ret = %s, terminated with "
3196 target_pid_to_str (ptid_of (current_thread
)),
3202 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3203 return filter_exit_event (event_child
, ourstatus
);
3205 return ptid_of (current_thread
);
3208 /* If step-over executes a breakpoint instruction, in the case of a
3209 hardware single step it means a gdb/gdbserver breakpoint had been
3210 planted on top of a permanent breakpoint, in the case of a software
3211 single step it may just mean that gdbserver hit the reinsert breakpoint.
3212 The PC has been adjusted by check_stopped_by_breakpoint to point at
3213 the breakpoint address.
3214 So in the case of the hardware single step advance the PC manually
3215 past the breakpoint and in the case of software single step advance only
3216 if it's not the reinsert_breakpoint we are hitting.
3217 This avoids that a program would keep trapping a permanent breakpoint
3219 if (!ptid_equal (step_over_bkpt
, null_ptid
)
3220 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3221 && (event_child
->stepping
3222 || !reinsert_breakpoint_inserted_here (event_child
->stop_pc
)))
3224 int increment_pc
= 0;
3225 int breakpoint_kind
= 0;
3226 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3229 the_target
->breakpoint_kind_from_current_state (&stop_pc
);
3230 the_target
->sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3234 debug_printf ("step-over for %s executed software breakpoint\n",
3235 target_pid_to_str (ptid_of (current_thread
)));
3238 if (increment_pc
!= 0)
3240 struct regcache
*regcache
3241 = get_thread_regcache (current_thread
, 1);
3243 event_child
->stop_pc
+= increment_pc
;
3244 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3246 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
3247 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3251 /* If this event was not handled before, and is not a SIGTRAP, we
3252 report it. SIGILL and SIGSEGV are also treated as traps in case
3253 a breakpoint is inserted at the current PC. If this target does
3254 not support internal breakpoints at all, we also report the
3255 SIGTRAP without further processing; it's of no concern to us. */
3257 = (supports_breakpoints ()
3258 && (WSTOPSIG (w
) == SIGTRAP
3259 || ((WSTOPSIG (w
) == SIGILL
3260 || WSTOPSIG (w
) == SIGSEGV
)
3261 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
3263 if (maybe_internal_trap
)
3265 /* Handle anything that requires bookkeeping before deciding to
3266 report the event or continue waiting. */
3268 /* First check if we can explain the SIGTRAP with an internal
3269 breakpoint, or if we should possibly report the event to GDB.
3270 Do this before anything that may remove or insert a
3272 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3274 /* We have a SIGTRAP, possibly a step-over dance has just
3275 finished. If so, tweak the state machine accordingly,
3276 reinsert breakpoints and delete any reinsert (software
3277 single-step) breakpoints. */
3278 step_over_finished
= finish_step_over (event_child
);
3280 /* Now invoke the callbacks of any internal breakpoints there. */
3281 check_breakpoints (event_child
->stop_pc
);
3283 /* Handle tracepoint data collecting. This may overflow the
3284 trace buffer, and cause a tracing stop, removing
3286 trace_event
= handle_tracepoints (event_child
);
3288 if (bp_explains_trap
)
3290 /* If we stepped or ran into an internal breakpoint, we've
3291 already handled it. So next time we resume (from this
3292 PC), we should step over it. */
3294 debug_printf ("Hit a gdbserver breakpoint.\n");
3296 if (breakpoint_here (event_child
->stop_pc
))
3297 event_child
->need_step_over
= 1;
3302 /* We have some other signal, possibly a step-over dance was in
3303 progress, and it should be cancelled too. */
3304 step_over_finished
= finish_step_over (event_child
);
3307 /* We have all the data we need. Either report the event to GDB, or
3308 resume threads and keep waiting for more. */
3310 /* If we're collecting a fast tracepoint, finish the collection and
3311 move out of the jump pad before delivering a signal. See
3312 linux_stabilize_threads. */
3315 && WSTOPSIG (w
) != SIGTRAP
3316 && supports_fast_tracepoints ()
3317 && agent_loaded_p ())
3320 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3321 "to defer or adjust it.\n",
3322 WSTOPSIG (w
), lwpid_of (current_thread
));
3324 /* Allow debugging the jump pad itself. */
3325 if (current_thread
->last_resume_kind
!= resume_step
3326 && maybe_move_out_of_jump_pad (event_child
, &w
))
3328 enqueue_one_deferred_signal (event_child
, &w
);
3331 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3332 WSTOPSIG (w
), lwpid_of (current_thread
));
3334 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
3336 return ignore_event (ourstatus
);
3340 if (event_child
->collecting_fast_tracepoint
)
3343 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3344 "Check if we're already there.\n",
3345 lwpid_of (current_thread
),
3346 event_child
->collecting_fast_tracepoint
);
3350 event_child
->collecting_fast_tracepoint
3351 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3353 if (event_child
->collecting_fast_tracepoint
!= 1)
3355 /* No longer need this breakpoint. */
3356 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3359 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3360 "stopping all threads momentarily.\n");
3362 /* Other running threads could hit this breakpoint.
3363 We don't handle moribund locations like GDB does,
3364 instead we always pause all threads when removing
3365 breakpoints, so that any step-over or
3366 decr_pc_after_break adjustment is always taken
3367 care of while the breakpoint is still
3369 stop_all_lwps (1, event_child
);
3371 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3372 event_child
->exit_jump_pad_bkpt
= NULL
;
3374 unstop_all_lwps (1, event_child
);
3376 gdb_assert (event_child
->suspended
>= 0);
3380 if (event_child
->collecting_fast_tracepoint
== 0)
3383 debug_printf ("fast tracepoint finished "
3384 "collecting successfully.\n");
3386 /* We may have a deferred signal to report. */
3387 if (dequeue_one_deferred_signal (event_child
, &w
))
3390 debug_printf ("dequeued one signal.\n");
3395 debug_printf ("no deferred signals.\n");
3397 if (stabilizing_threads
)
3399 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3400 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3404 debug_printf ("linux_wait_1 ret = %s, stopped "
3405 "while stabilizing threads\n",
3406 target_pid_to_str (ptid_of (current_thread
)));
3410 return ptid_of (current_thread
);
3416 /* Check whether GDB would be interested in this event. */
3418 /* Check if GDB is interested in this syscall. */
3420 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3421 && !gdb_catch_this_syscall_p (event_child
))
3425 debug_printf ("Ignored syscall for LWP %ld.\n",
3426 lwpid_of (current_thread
));
3429 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3431 return ignore_event (ourstatus
);
3434 /* If GDB is not interested in this signal, don't stop other
3435 threads, and don't report it to GDB. Just resume the inferior
3436 right away. We do this for threading-related signals as well as
3437 any that GDB specifically requested we ignore. But never ignore
3438 SIGSTOP if we sent it ourselves, and do not ignore signals when
3439 stepping - they may require special handling to skip the signal
3440 handler. Also never ignore signals that could be caused by a
3443 && current_thread
->last_resume_kind
!= resume_step
3445 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3446 (current_process ()->priv
->thread_db
!= NULL
3447 && (WSTOPSIG (w
) == __SIGRTMIN
3448 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3451 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3452 && !(WSTOPSIG (w
) == SIGSTOP
3453 && current_thread
->last_resume_kind
== resume_stop
)
3454 && !linux_wstatus_maybe_breakpoint (w
))))
3456 siginfo_t info
, *info_p
;
3459 debug_printf ("Ignored signal %d for LWP %ld.\n",
3460 WSTOPSIG (w
), lwpid_of (current_thread
));
3462 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3463 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3468 if (step_over_finished
)
3470 /* We cancelled this thread's step-over above. We still
3471 need to unsuspend all other LWPs, and set them back
3472 running again while the signal handler runs. */
3473 unsuspend_all_lwps (event_child
);
3475 /* Enqueue the pending signal info so that proceed_all_lwps
3477 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3479 proceed_all_lwps ();
3483 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3484 WSTOPSIG (w
), info_p
);
3486 return ignore_event (ourstatus
);
3489 /* Note that all addresses are always "out of the step range" when
3490 there's no range to begin with. */
3491 in_step_range
= lwp_in_step_range (event_child
);
3493 /* If GDB wanted this thread to single step, and the thread is out
3494 of the step range, we always want to report the SIGTRAP, and let
3495 GDB handle it. Watchpoints should always be reported. So should
3496 signals we can't explain. A SIGTRAP we can't explain could be a
3497 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3498 do, we're be able to handle GDB breakpoints on top of internal
3499 breakpoints, by handling the internal breakpoint and still
3500 reporting the event to GDB. If we don't, we're out of luck, GDB
3501 won't see the breakpoint hit. If we see a single-step event but
3502 the thread should be continuing, don't pass the trap to gdb.
3503 That indicates that we had previously finished a single-step but
3504 left the single-step pending -- see
3505 complete_ongoing_step_over. */
3506 report_to_gdb
= (!maybe_internal_trap
3507 || (current_thread
->last_resume_kind
== resume_step
3509 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3511 && !bp_explains_trap
3513 && !step_over_finished
3514 && !(current_thread
->last_resume_kind
== resume_continue
3515 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3516 || (gdb_breakpoint_here (event_child
->stop_pc
)
3517 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3518 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3519 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3521 run_breakpoint_commands (event_child
->stop_pc
);
3523 /* We found no reason GDB would want us to stop. We either hit one
3524 of our own breakpoints, or finished an internal step GDB
3525 shouldn't know about. */
3530 if (bp_explains_trap
)
3531 debug_printf ("Hit a gdbserver breakpoint.\n");
3532 if (step_over_finished
)
3533 debug_printf ("Step-over finished.\n");
3535 debug_printf ("Tracepoint event.\n");
3536 if (lwp_in_step_range (event_child
))
3537 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3538 paddress (event_child
->stop_pc
),
3539 paddress (event_child
->step_range_start
),
3540 paddress (event_child
->step_range_end
));
3543 /* We're not reporting this breakpoint to GDB, so apply the
3544 decr_pc_after_break adjustment to the inferior's regcache
3547 if (the_low_target
.set_pc
!= NULL
)
3549 struct regcache
*regcache
3550 = get_thread_regcache (current_thread
, 1);
3551 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3554 /* We may have finished stepping over a breakpoint. If so,
3555 we've stopped and suspended all LWPs momentarily except the
3556 stepping one. This is where we resume them all again. We're
3557 going to keep waiting, so use proceed, which handles stepping
3558 over the next breakpoint. */
3560 debug_printf ("proceeding all threads.\n");
3562 if (step_over_finished
)
3563 unsuspend_all_lwps (event_child
);
3565 proceed_all_lwps ();
3566 return ignore_event (ourstatus
);
3571 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3575 str
= target_waitstatus_to_string (&event_child
->waitstatus
);
3576 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3577 lwpid_of (get_lwp_thread (event_child
)), str
);
3580 if (current_thread
->last_resume_kind
== resume_step
)
3582 if (event_child
->step_range_start
== event_child
->step_range_end
)
3583 debug_printf ("GDB wanted to single-step, reporting event.\n");
3584 else if (!lwp_in_step_range (event_child
))
3585 debug_printf ("Out of step range, reporting event.\n");
3587 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3588 debug_printf ("Stopped by watchpoint.\n");
3589 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3590 debug_printf ("Stopped by GDB breakpoint.\n");
3592 debug_printf ("Hit a non-gdbserver trap event.\n");
3595 /* Alright, we're going to report a stop. */
3597 if (!stabilizing_threads
)
3599 /* In all-stop, stop all threads. */
3601 stop_all_lwps (0, NULL
);
3603 /* If we're not waiting for a specific LWP, choose an event LWP
3604 from among those that have had events. Giving equal priority
3605 to all LWPs that have had events helps prevent
3607 if (ptid_equal (ptid
, minus_one_ptid
))
3609 event_child
->status_pending_p
= 1;
3610 event_child
->status_pending
= w
;
3612 select_event_lwp (&event_child
);
3614 /* current_thread and event_child must stay in sync. */
3615 current_thread
= get_lwp_thread (event_child
);
3617 event_child
->status_pending_p
= 0;
3618 w
= event_child
->status_pending
;
3621 if (step_over_finished
)
3625 /* If we were doing a step-over, all other threads but
3626 the stepping one had been paused in start_step_over,
3627 with their suspend counts incremented. We don't want
3628 to do a full unstop/unpause, because we're in
3629 all-stop mode (so we want threads stopped), but we
3630 still need to unsuspend the other threads, to
3631 decrement their `suspended' count back. */
3632 unsuspend_all_lwps (event_child
);
3636 /* If we just finished a step-over, then all threads had
3637 been momentarily paused. In all-stop, that's fine,
3638 we want threads stopped by now anyway. In non-stop,
3639 we need to re-resume threads that GDB wanted to be
3641 unstop_all_lwps (1, event_child
);
3645 /* Stabilize threads (move out of jump pads). */
3647 stabilize_threads ();
3651 /* If we just finished a step-over, then all threads had been
3652 momentarily paused. In all-stop, that's fine, we want
3653 threads stopped by now anyway. In non-stop, we need to
3654 re-resume threads that GDB wanted to be running. */
3655 if (step_over_finished
)
3656 unstop_all_lwps (1, event_child
);
3659 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3661 /* If the reported event is an exit, fork, vfork or exec, let
3663 *ourstatus
= event_child
->waitstatus
;
3664 /* Clear the event lwp's waitstatus since we handled it already. */
3665 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3668 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3670 /* Now that we've selected our final event LWP, un-adjust its PC if
3671 it was a software breakpoint, and the client doesn't know we can
3672 adjust the breakpoint ourselves. */
3673 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3674 && !swbreak_feature
)
3676 int decr_pc
= the_low_target
.decr_pc_after_break
;
3680 struct regcache
*regcache
3681 = get_thread_regcache (current_thread
, 1);
3682 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3686 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3690 get_syscall_trapinfo (event_child
,
3691 &ourstatus
->value
.syscall_number
, &sysret
);
3692 ourstatus
->kind
= event_child
->syscall_state
;
3694 else if (current_thread
->last_resume_kind
== resume_stop
3695 && WSTOPSIG (w
) == SIGSTOP
)
3697 /* A thread that has been requested to stop by GDB with vCont;t,
3698 and it stopped cleanly, so report as SIG0. The use of
3699 SIGSTOP is an implementation detail. */
3700 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3702 else if (current_thread
->last_resume_kind
== resume_stop
3703 && WSTOPSIG (w
) != SIGSTOP
)
3705 /* A thread that has been requested to stop by GDB with vCont;t,
3706 but, it stopped for other reasons. */
3707 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3709 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3711 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3714 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
3718 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3719 target_pid_to_str (ptid_of (current_thread
)),
3720 ourstatus
->kind
, ourstatus
->value
.sig
);
3724 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3725 return filter_exit_event (event_child
, ourstatus
);
3727 return ptid_of (current_thread
);
3730 /* Get rid of any pending event in the pipe. */
3732 async_file_flush (void)
3738 ret
= read (linux_event_pipe
[0], &buf
, 1);
3739 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3742 /* Put something in the pipe, so the event loop wakes up. */
3744 async_file_mark (void)
3748 async_file_flush ();
3751 ret
= write (linux_event_pipe
[1], "+", 1);
3752 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3754 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3755 be awakened anyway. */
3759 linux_wait (ptid_t ptid
,
3760 struct target_waitstatus
*ourstatus
, int target_options
)
3764 /* Flush the async file first. */
3765 if (target_is_async_p ())
3766 async_file_flush ();
3770 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3772 while ((target_options
& TARGET_WNOHANG
) == 0
3773 && ptid_equal (event_ptid
, null_ptid
)
3774 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3776 /* If at least one stop was reported, there may be more. A single
3777 SIGCHLD can signal more than one child stop. */
3778 if (target_is_async_p ()
3779 && (target_options
& TARGET_WNOHANG
) != 0
3780 && !ptid_equal (event_ptid
, null_ptid
))
3786 /* Send a signal to an LWP. */
3789 kill_lwp (unsigned long lwpid
, int signo
)
3794 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3795 if (errno
== ENOSYS
)
3797 /* If tkill fails, then we are not using nptl threads, a
3798 configuration we no longer support. */
3799 perror_with_name (("tkill"));
3805 linux_stop_lwp (struct lwp_info
*lwp
)
3811 send_sigstop (struct lwp_info
*lwp
)
3815 pid
= lwpid_of (get_lwp_thread (lwp
));
3817 /* If we already have a pending stop signal for this process, don't
3819 if (lwp
->stop_expected
)
3822 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3828 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3830 lwp
->stop_expected
= 1;
3831 kill_lwp (pid
, SIGSTOP
);
3835 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
3837 struct thread_info
*thread
= (struct thread_info
*) entry
;
3838 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3840 /* Ignore EXCEPT. */
3851 /* Increment the suspend count of an LWP, and stop it, if not stopped
3854 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
3857 struct thread_info
*thread
= (struct thread_info
*) entry
;
3858 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3860 /* Ignore EXCEPT. */
3864 lwp_suspended_inc (lwp
);
3866 return send_sigstop_callback (entry
, except
);
3870 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3872 /* Store the exit status for later. */
3873 lwp
->status_pending_p
= 1;
3874 lwp
->status_pending
= wstat
;
3876 /* Store in waitstatus as well, as there's nothing else to process
3878 if (WIFEXITED (wstat
))
3880 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3881 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3883 else if (WIFSIGNALED (wstat
))
3885 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3886 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3889 /* Prevent trying to stop it. */
3892 /* No further stops are expected from a dead lwp. */
3893 lwp
->stop_expected
= 0;
3896 /* Return true if LWP has exited already, and has a pending exit event
3897 to report to GDB. */
3900 lwp_is_marked_dead (struct lwp_info
*lwp
)
3902 return (lwp
->status_pending_p
3903 && (WIFEXITED (lwp
->status_pending
)
3904 || WIFSIGNALED (lwp
->status_pending
)));
3907 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3910 wait_for_sigstop (void)
3912 struct thread_info
*saved_thread
;
3917 saved_thread
= current_thread
;
3918 if (saved_thread
!= NULL
)
3919 saved_tid
= saved_thread
->entry
.id
;
3921 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3924 debug_printf ("wait_for_sigstop: pulling events\n");
3926 /* Passing NULL_PTID as filter indicates we want all events to be
3927 left pending. Eventually this returns when there are no
3928 unwaited-for children left. */
3929 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
3931 gdb_assert (ret
== -1);
3933 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
3934 current_thread
= saved_thread
;
3938 debug_printf ("Previously current thread died.\n");
3940 /* We can't change the current inferior behind GDB's back,
3941 otherwise, a subsequent command may apply to the wrong
3943 current_thread
= NULL
;
3947 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3948 move it out, because we need to report the stop event to GDB. For
3949 example, if the user puts a breakpoint in the jump pad, it's
3950 because she wants to debug it. */
3953 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3955 struct thread_info
*thread
= (struct thread_info
*) entry
;
3956 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3958 if (lwp
->suspended
!= 0)
3960 internal_error (__FILE__
, __LINE__
,
3961 "LWP %ld is suspended, suspended=%d\n",
3962 lwpid_of (thread
), lwp
->suspended
);
3964 gdb_assert (lwp
->stopped
);
3966 /* Allow debugging the jump pad, gdb_collect, etc.. */
3967 return (supports_fast_tracepoints ()
3968 && agent_loaded_p ()
3969 && (gdb_breakpoint_here (lwp
->stop_pc
)
3970 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3971 || thread
->last_resume_kind
== resume_step
)
3972 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3976 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3978 struct thread_info
*thread
= (struct thread_info
*) entry
;
3979 struct thread_info
*saved_thread
;
3980 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3983 if (lwp
->suspended
!= 0)
3985 internal_error (__FILE__
, __LINE__
,
3986 "LWP %ld is suspended, suspended=%d\n",
3987 lwpid_of (thread
), lwp
->suspended
);
3989 gdb_assert (lwp
->stopped
);
3991 /* For gdb_breakpoint_here. */
3992 saved_thread
= current_thread
;
3993 current_thread
= thread
;
3995 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3997 /* Allow debugging the jump pad, gdb_collect, etc. */
3998 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3999 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
4000 && thread
->last_resume_kind
!= resume_step
4001 && maybe_move_out_of_jump_pad (lwp
, wstat
))
4004 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
4009 lwp
->status_pending_p
= 0;
4010 enqueue_one_deferred_signal (lwp
, wstat
);
4013 debug_printf ("Signal %d for LWP %ld deferred "
4015 WSTOPSIG (*wstat
), lwpid_of (thread
));
4018 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
4021 lwp_suspended_inc (lwp
);
4023 current_thread
= saved_thread
;
4027 lwp_running (struct inferior_list_entry
*entry
, void *data
)
4029 struct thread_info
*thread
= (struct thread_info
*) entry
;
4030 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4032 if (lwp_is_marked_dead (lwp
))
4039 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
4040 If SUSPEND, then also increase the suspend count of every LWP,
4044 stop_all_lwps (int suspend
, struct lwp_info
*except
)
4046 /* Should not be called recursively. */
4047 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
4052 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4053 suspend
? "stop-and-suspend" : "stop",
4055 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
4059 stopping_threads
= (suspend
4060 ? STOPPING_AND_SUSPENDING_THREADS
4061 : STOPPING_THREADS
);
4064 find_inferior (&all_threads
, suspend_and_send_sigstop_callback
, except
);
4066 find_inferior (&all_threads
, send_sigstop_callback
, except
);
4067 wait_for_sigstop ();
4068 stopping_threads
= NOT_STOPPING_THREADS
;
4072 debug_printf ("stop_all_lwps done, setting stopping_threads "
4073 "back to !stopping\n");
4078 /* Enqueue one signal in the chain of signals which need to be
4079 delivered to this process on next resume. */
4082 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
4084 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
4086 p_sig
->prev
= lwp
->pending_signals
;
4087 p_sig
->signal
= signal
;
4089 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4091 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
4092 lwp
->pending_signals
= p_sig
;
4095 /* Install breakpoints for software single stepping. */
4098 install_software_single_step_breakpoints (struct lwp_info
*lwp
)
4102 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4103 VEC (CORE_ADDR
) *next_pcs
= NULL
;
4104 struct cleanup
*old_chain
= make_cleanup (VEC_cleanup (CORE_ADDR
), &next_pcs
);
4107 next_pcs
= (*the_low_target
.get_next_pcs
) (pc
, regcache
);
4109 for (i
= 0; VEC_iterate (CORE_ADDR
, next_pcs
, i
, pc
); ++i
)
4110 set_reinsert_breakpoint (pc
);
4112 do_cleanups (old_chain
);
4115 /* Single step via hardware or software single step.
4116 Return 1 if hardware single stepping, 0 if software single stepping
4117 or can't single step. */
4120 single_step (struct lwp_info
* lwp
)
4124 if (can_hardware_single_step ())
4128 else if (can_software_single_step ())
4130 install_software_single_step_breakpoints (lwp
);
4136 debug_printf ("stepping is not implemented on this target");
4142 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
4143 SIGNAL is nonzero, give it that signal. */
4146 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
4147 int step
, int signal
, siginfo_t
*info
)
4149 struct thread_info
*thread
= get_lwp_thread (lwp
);
4150 struct thread_info
*saved_thread
;
4151 int fast_tp_collecting
;
4153 struct process_info
*proc
= get_thread_process (thread
);
4155 /* Note that target description may not be initialised
4156 (proc->tdesc == NULL) at this point because the program hasn't
4157 stopped at the first instruction yet. It means GDBserver skips
4158 the extra traps from the wrapper program (see option --wrapper).
4159 Code in this function that requires register access should be
4160 guarded by proc->tdesc == NULL or something else. */
4162 if (lwp
->stopped
== 0)
4165 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
4167 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
4169 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
4171 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4172 user used the "jump" command, or "set $pc = foo"). */
4173 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
4175 /* Collecting 'while-stepping' actions doesn't make sense
4177 release_while_stepping_state_list (thread
);
4180 /* If we have pending signals or status, and a new signal, enqueue the
4181 signal. Also enqueue the signal if we are waiting to reinsert a
4182 breakpoint; it will be picked up again below. */
4184 && (lwp
->status_pending_p
4185 || lwp
->pending_signals
!= NULL
4186 || lwp
->bp_reinsert
!= 0
4187 || fast_tp_collecting
))
4189 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
4191 p_sig
->prev
= lwp
->pending_signals
;
4192 p_sig
->signal
= signal
;
4194 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4196 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
4197 lwp
->pending_signals
= p_sig
;
4200 if (lwp
->status_pending_p
)
4203 debug_printf ("Not resuming lwp %ld (%s, signal %d, stop %s);"
4204 " has pending status\n",
4205 lwpid_of (thread
), step
? "step" : "continue", signal
,
4206 lwp
->stop_expected
? "expected" : "not expected");
4210 saved_thread
= current_thread
;
4211 current_thread
= thread
;
4214 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4215 lwpid_of (thread
), step
? "step" : "continue", signal
,
4216 lwp
->stop_expected
? "expected" : "not expected");
4218 /* This bit needs some thinking about. If we get a signal that
4219 we must report while a single-step reinsert is still pending,
4220 we often end up resuming the thread. It might be better to
4221 (ew) allow a stack of pending events; then we could be sure that
4222 the reinsert happened right away and not lose any signals.
4224 Making this stack would also shrink the window in which breakpoints are
4225 uninserted (see comment in linux_wait_for_lwp) but not enough for
4226 complete correctness, so it won't solve that problem. It may be
4227 worthwhile just to solve this one, however. */
4228 if (lwp
->bp_reinsert
!= 0)
4231 debug_printf (" pending reinsert at 0x%s\n",
4232 paddress (lwp
->bp_reinsert
));
4234 if (can_hardware_single_step ())
4236 if (fast_tp_collecting
== 0)
4239 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
4241 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
4248 /* Postpone any pending signal. It was enqueued above. */
4252 if (fast_tp_collecting
== 1)
4255 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4256 " (exit-jump-pad-bkpt)\n",
4259 /* Postpone any pending signal. It was enqueued above. */
4262 else if (fast_tp_collecting
== 2)
4265 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4266 " single-stepping\n",
4269 if (can_hardware_single_step ())
4273 internal_error (__FILE__
, __LINE__
,
4274 "moving out of jump pad single-stepping"
4275 " not implemented on this target");
4278 /* Postpone any pending signal. It was enqueued above. */
4282 /* If we have while-stepping actions in this thread set it stepping.
4283 If we have a signal to deliver, it may or may not be set to
4284 SIG_IGN, we don't know. Assume so, and allow collecting
4285 while-stepping into a signal handler. A possible smart thing to
4286 do would be to set an internal breakpoint at the signal return
4287 address, continue, and carry on catching this while-stepping
4288 action only when that breakpoint is hit. A future
4290 if (thread
->while_stepping
!= NULL
)
4293 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4296 step
= single_step (lwp
);
4299 if (proc
->tdesc
!= NULL
&& the_low_target
.get_pc
!= NULL
)
4301 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4303 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
4307 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4308 (long) lwp
->stop_pc
);
4312 /* If we have pending signals, consume one unless we are trying to
4313 reinsert a breakpoint or we're trying to finish a fast tracepoint
4315 if (lwp
->pending_signals
!= NULL
4316 && lwp
->bp_reinsert
== 0
4317 && fast_tp_collecting
== 0)
4319 struct pending_signals
**p_sig
;
4321 p_sig
= &lwp
->pending_signals
;
4322 while ((*p_sig
)->prev
!= NULL
)
4323 p_sig
= &(*p_sig
)->prev
;
4325 signal
= (*p_sig
)->signal
;
4326 if ((*p_sig
)->info
.si_signo
!= 0)
4327 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4334 if (the_low_target
.prepare_to_resume
!= NULL
)
4335 the_low_target
.prepare_to_resume (lwp
);
4337 regcache_invalidate_thread (thread
);
4339 lwp
->stepping
= step
;
4341 ptrace_request
= PTRACE_SINGLESTEP
;
4342 else if (gdb_catching_syscalls_p (lwp
))
4343 ptrace_request
= PTRACE_SYSCALL
;
4345 ptrace_request
= PTRACE_CONT
;
4346 ptrace (ptrace_request
,
4348 (PTRACE_TYPE_ARG3
) 0,
4349 /* Coerce to a uintptr_t first to avoid potential gcc warning
4350 of coercing an 8 byte integer to a 4 byte pointer. */
4351 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4353 current_thread
= saved_thread
;
4355 perror_with_name ("resuming thread");
4357 /* Successfully resumed. Clear state that no longer makes sense,
4358 and mark the LWP as running. Must not do this before resuming
4359 otherwise if that fails other code will be confused. E.g., we'd
4360 later try to stop the LWP and hang forever waiting for a stop
4361 status. Note that we must not throw after this is cleared,
4362 otherwise handle_zombie_lwp_error would get confused. */
4364 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4367 /* Called when we try to resume a stopped LWP and that errors out. If
4368 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4369 or about to become), discard the error, clear any pending status
4370 the LWP may have, and return true (we'll collect the exit status
4371 soon enough). Otherwise, return false. */
4374 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4376 struct thread_info
*thread
= get_lwp_thread (lp
);
4378 /* If we get an error after resuming the LWP successfully, we'd
4379 confuse !T state for the LWP being gone. */
4380 gdb_assert (lp
->stopped
);
4382 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4383 because even if ptrace failed with ESRCH, the tracee may be "not
4384 yet fully dead", but already refusing ptrace requests. In that
4385 case the tracee has 'R (Running)' state for a little bit
4386 (observed in Linux 3.18). See also the note on ESRCH in the
4387 ptrace(2) man page. Instead, check whether the LWP has any state
4388 other than ptrace-stopped. */
4390 /* Don't assume anything if /proc/PID/status can't be read. */
4391 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4393 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4394 lp
->status_pending_p
= 0;
4400 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4401 disappears while we try to resume it. */
4404 linux_resume_one_lwp (struct lwp_info
*lwp
,
4405 int step
, int signal
, siginfo_t
*info
)
4409 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
4411 CATCH (ex
, RETURN_MASK_ERROR
)
4413 if (!check_ptrace_stopped_lwp_gone (lwp
))
4414 throw_exception (ex
);
4419 struct thread_resume_array
4421 struct thread_resume
*resume
;
4425 /* This function is called once per thread via find_inferior.
4426 ARG is a pointer to a thread_resume_array struct.
4427 We look up the thread specified by ENTRY in ARG, and mark the thread
4428 with a pointer to the appropriate resume request.
4430 This algorithm is O(threads * resume elements), but resume elements
4431 is small (and will remain small at least until GDB supports thread
4435 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
4437 struct thread_info
*thread
= (struct thread_info
*) entry
;
4438 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4440 struct thread_resume_array
*r
;
4442 r
= (struct thread_resume_array
*) arg
;
4444 for (ndx
= 0; ndx
< r
->n
; ndx
++)
4446 ptid_t ptid
= r
->resume
[ndx
].thread
;
4447 if (ptid_equal (ptid
, minus_one_ptid
)
4448 || ptid_equal (ptid
, entry
->id
)
4449 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4451 || (ptid_get_pid (ptid
) == pid_of (thread
)
4452 && (ptid_is_pid (ptid
)
4453 || ptid_get_lwp (ptid
) == -1)))
4455 if (r
->resume
[ndx
].kind
== resume_stop
4456 && thread
->last_resume_kind
== resume_stop
)
4459 debug_printf ("already %s LWP %ld at GDB's request\n",
4460 (thread
->last_status
.kind
4461 == TARGET_WAITKIND_STOPPED
)
4469 lwp
->resume
= &r
->resume
[ndx
];
4470 thread
->last_resume_kind
= lwp
->resume
->kind
;
4472 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4473 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4475 /* If we had a deferred signal to report, dequeue one now.
4476 This can happen if LWP gets more than one signal while
4477 trying to get out of a jump pad. */
4479 && !lwp
->status_pending_p
4480 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4482 lwp
->status_pending_p
= 1;
4485 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4486 "leaving status pending.\n",
4487 WSTOPSIG (lwp
->status_pending
),
4495 /* No resume action for this thread. */
4501 /* find_inferior callback for linux_resume.
4502 Set *FLAG_P if this lwp has an interesting status pending. */
4505 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
4507 struct thread_info
*thread
= (struct thread_info
*) entry
;
4508 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4510 /* LWPs which will not be resumed are not interesting, because
4511 we might not wait for them next time through linux_wait. */
4512 if (lwp
->resume
== NULL
)
4515 if (thread_still_has_status_pending_p (thread
))
4516 * (int *) flag_p
= 1;
4521 /* Return 1 if this lwp that GDB wants running is stopped at an
4522 internal breakpoint that we need to step over. It assumes that any
4523 required STOP_PC adjustment has already been propagated to the
4524 inferior's regcache. */
4527 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
4529 struct thread_info
*thread
= (struct thread_info
*) entry
;
4530 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4531 struct thread_info
*saved_thread
;
4533 struct process_info
*proc
= get_thread_process (thread
);
4535 /* GDBserver is skipping the extra traps from the wrapper program,
4536 don't have to do step over. */
4537 if (proc
->tdesc
== NULL
)
4540 /* LWPs which will not be resumed are not interesting, because we
4541 might not wait for them next time through linux_wait. */
4546 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4551 if (thread
->last_resume_kind
== resume_stop
)
4554 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4560 gdb_assert (lwp
->suspended
>= 0);
4565 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4570 if (!lwp
->need_step_over
)
4573 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (thread
));
4576 if (lwp
->status_pending_p
)
4579 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4585 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4589 /* If the PC has changed since we stopped, then don't do anything,
4590 and let the breakpoint/tracepoint be hit. This happens if, for
4591 instance, GDB handled the decr_pc_after_break subtraction itself,
4592 GDB is OOL stepping this thread, or the user has issued a "jump"
4593 command, or poked thread's registers herself. */
4594 if (pc
!= lwp
->stop_pc
)
4597 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4598 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4600 paddress (lwp
->stop_pc
), paddress (pc
));
4602 lwp
->need_step_over
= 0;
4606 saved_thread
= current_thread
;
4607 current_thread
= thread
;
4609 /* We can only step over breakpoints we know about. */
4610 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4612 /* Don't step over a breakpoint that GDB expects to hit
4613 though. If the condition is being evaluated on the target's side
4614 and it evaluate to false, step over this breakpoint as well. */
4615 if (gdb_breakpoint_here (pc
)
4616 && gdb_condition_true_at_breakpoint (pc
)
4617 && gdb_no_commands_at_breakpoint (pc
))
4620 debug_printf ("Need step over [LWP %ld]? yes, but found"
4621 " GDB breakpoint at 0x%s; skipping step over\n",
4622 lwpid_of (thread
), paddress (pc
));
4624 current_thread
= saved_thread
;
4630 debug_printf ("Need step over [LWP %ld]? yes, "
4631 "found breakpoint at 0x%s\n",
4632 lwpid_of (thread
), paddress (pc
));
4634 /* We've found an lwp that needs stepping over --- return 1 so
4635 that find_inferior stops looking. */
4636 current_thread
= saved_thread
;
4638 /* If the step over is cancelled, this is set again. */
4639 lwp
->need_step_over
= 0;
4644 current_thread
= saved_thread
;
4647 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4649 lwpid_of (thread
), paddress (pc
));
4654 /* Start a step-over operation on LWP. When LWP stopped at a
4655 breakpoint, to make progress, we need to remove the breakpoint out
4656 of the way. If we let other threads run while we do that, they may
4657 pass by the breakpoint location and miss hitting it. To avoid
4658 that, a step-over momentarily stops all threads while LWP is
4659 single-stepped while the breakpoint is temporarily uninserted from
4660 the inferior. When the single-step finishes, we reinsert the
4661 breakpoint, and let all threads that are supposed to be running,
4664 On targets that don't support hardware single-step, we don't
4665 currently support full software single-stepping. Instead, we only
4666 support stepping over the thread event breakpoint, by asking the
4667 low target where to place a reinsert breakpoint. Since this
4668 routine assumes the breakpoint being stepped over is a thread event
4669 breakpoint, it usually assumes the return address of the current
4670 function is a good enough place to set the reinsert breakpoint. */
4673 start_step_over (struct lwp_info
*lwp
)
4675 struct thread_info
*thread
= get_lwp_thread (lwp
);
4676 struct thread_info
*saved_thread
;
4681 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4684 stop_all_lwps (1, lwp
);
4686 if (lwp
->suspended
!= 0)
4688 internal_error (__FILE__
, __LINE__
,
4689 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4694 debug_printf ("Done stopping all threads for step-over.\n");
4696 /* Note, we should always reach here with an already adjusted PC,
4697 either by GDB (if we're resuming due to GDB's request), or by our
4698 caller, if we just finished handling an internal breakpoint GDB
4699 shouldn't care about. */
4702 saved_thread
= current_thread
;
4703 current_thread
= thread
;
4705 lwp
->bp_reinsert
= pc
;
4706 uninsert_breakpoints_at (pc
);
4707 uninsert_fast_tracepoint_jumps_at (pc
);
4709 step
= single_step (lwp
);
4711 current_thread
= saved_thread
;
4713 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4715 /* Require next event from this LWP. */
4716 step_over_bkpt
= thread
->entry
.id
;
4720 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4721 start_step_over, if still there, and delete any reinsert
4722 breakpoints we've set, on non hardware single-step targets. */
4725 finish_step_over (struct lwp_info
*lwp
)
4727 if (lwp
->bp_reinsert
!= 0)
4730 debug_printf ("Finished step over.\n");
4732 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4733 may be no breakpoint to reinsert there by now. */
4734 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4735 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4737 lwp
->bp_reinsert
= 0;
4739 /* Delete any software-single-step reinsert breakpoints. No
4740 longer needed. We don't have to worry about other threads
4741 hitting this trap, and later not being able to explain it,
4742 because we were stepping over a breakpoint, and we hold all
4743 threads but LWP stopped while doing that. */
4744 if (!can_hardware_single_step ())
4745 delete_reinsert_breakpoints ();
4747 step_over_bkpt
= null_ptid
;
4754 /* If there's a step over in progress, wait until all threads stop
4755 (that is, until the stepping thread finishes its step), and
4756 unsuspend all lwps. The stepping thread ends with its status
4757 pending, which is processed later when we get back to processing
4761 complete_ongoing_step_over (void)
4763 if (!ptid_equal (step_over_bkpt
, null_ptid
))
4765 struct lwp_info
*lwp
;
4770 debug_printf ("detach: step over in progress, finish it first\n");
4772 /* Passing NULL_PTID as filter indicates we want all events to
4773 be left pending. Eventually this returns when there are no
4774 unwaited-for children left. */
4775 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4777 gdb_assert (ret
== -1);
4779 lwp
= find_lwp_pid (step_over_bkpt
);
4781 finish_step_over (lwp
);
4782 step_over_bkpt
= null_ptid
;
4783 unsuspend_all_lwps (lwp
);
4787 /* This function is called once per thread. We check the thread's resume
4788 request, which will tell us whether to resume, step, or leave the thread
4789 stopped; and what signal, if any, it should be sent.
4791 For threads which we aren't explicitly told otherwise, we preserve
4792 the stepping flag; this is used for stepping over gdbserver-placed
4795 If pending_flags was set in any thread, we queue any needed
4796 signals, since we won't actually resume. We already have a pending
4797 event to report, so we don't need to preserve any step requests;
4798 they should be re-issued if necessary. */
4801 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
4803 struct thread_info
*thread
= (struct thread_info
*) entry
;
4804 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4806 int leave_all_stopped
= * (int *) arg
;
4809 if (lwp
->resume
== NULL
)
4812 if (lwp
->resume
->kind
== resume_stop
)
4815 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4820 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4822 /* Stop the thread, and wait for the event asynchronously,
4823 through the event loop. */
4829 debug_printf ("already stopped LWP %ld\n",
4832 /* The LWP may have been stopped in an internal event that
4833 was not meant to be notified back to GDB (e.g., gdbserver
4834 breakpoint), so we should be reporting a stop event in
4837 /* If the thread already has a pending SIGSTOP, this is a
4838 no-op. Otherwise, something later will presumably resume
4839 the thread and this will cause it to cancel any pending
4840 operation, due to last_resume_kind == resume_stop. If
4841 the thread already has a pending status to report, we
4842 will still report it the next time we wait - see
4843 status_pending_p_callback. */
4845 /* If we already have a pending signal to report, then
4846 there's no need to queue a SIGSTOP, as this means we're
4847 midway through moving the LWP out of the jumppad, and we
4848 will report the pending signal as soon as that is
4850 if (lwp
->pending_signals_to_report
== NULL
)
4854 /* For stop requests, we're done. */
4856 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4860 /* If this thread which is about to be resumed has a pending status,
4861 then don't resume it - we can just report the pending status.
4862 Likewise if it is suspended, because e.g., another thread is
4863 stepping past a breakpoint. Make sure to queue any signals that
4864 would otherwise be sent. In all-stop mode, we do this decision
4865 based on if *any* thread has a pending status. If there's a
4866 thread that needs the step-over-breakpoint dance, then don't
4867 resume any other thread but that particular one. */
4868 leave_pending
= (lwp
->suspended
4869 || lwp
->status_pending_p
4870 || leave_all_stopped
);
4875 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4877 step
= (lwp
->resume
->kind
== resume_step
);
4878 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
4883 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4885 /* If we have a new signal, enqueue the signal. */
4886 if (lwp
->resume
->sig
!= 0)
4888 struct pending_signals
*p_sig
= XCNEW (struct pending_signals
);
4890 p_sig
->prev
= lwp
->pending_signals
;
4891 p_sig
->signal
= lwp
->resume
->sig
;
4893 /* If this is the same signal we were previously stopped by,
4894 make sure to queue its siginfo. We can ignore the return
4895 value of ptrace; if it fails, we'll skip
4896 PTRACE_SETSIGINFO. */
4897 if (WIFSTOPPED (lwp
->last_status
)
4898 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
4899 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4902 lwp
->pending_signals
= p_sig
;
4906 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4912 linux_resume (struct thread_resume
*resume_info
, size_t n
)
4914 struct thread_resume_array array
= { resume_info
, n
};
4915 struct thread_info
*need_step_over
= NULL
;
4917 int leave_all_stopped
;
4922 debug_printf ("linux_resume:\n");
4925 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
4927 /* If there is a thread which would otherwise be resumed, which has
4928 a pending status, then don't resume any threads - we can just
4929 report the pending status. Make sure to queue any signals that
4930 would otherwise be sent. In non-stop mode, we'll apply this
4931 logic to each thread individually. We consume all pending events
4932 before considering to start a step-over (in all-stop). */
4935 find_inferior (&all_threads
, resume_status_pending_p
, &any_pending
);
4937 /* If there is a thread which would otherwise be resumed, which is
4938 stopped at a breakpoint that needs stepping over, then don't
4939 resume any threads - have it step over the breakpoint with all
4940 other threads stopped, then resume all threads again. Make sure
4941 to queue any signals that would otherwise be delivered or
4943 if (!any_pending
&& supports_breakpoints ())
4945 = (struct thread_info
*) find_inferior (&all_threads
,
4946 need_step_over_p
, NULL
);
4948 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4952 if (need_step_over
!= NULL
)
4953 debug_printf ("Not resuming all, need step over\n");
4954 else if (any_pending
)
4955 debug_printf ("Not resuming, all-stop and found "
4956 "an LWP with pending status\n");
4958 debug_printf ("Resuming, no pending status or step over needed\n");
4961 /* Even if we're leaving threads stopped, queue all signals we'd
4962 otherwise deliver. */
4963 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
4966 start_step_over (get_thread_lwp (need_step_over
));
4970 debug_printf ("linux_resume done\n");
4974 /* We may have events that were pending that can/should be sent to
4975 the client now. Trigger a linux_wait call. */
4976 if (target_is_async_p ())
4980 /* This function is called once per thread. We check the thread's
4981 last resume request, which will tell us whether to resume, step, or
4982 leave the thread stopped. Any signal the client requested to be
4983 delivered has already been enqueued at this point.
4985 If any thread that GDB wants running is stopped at an internal
4986 breakpoint that needs stepping over, we start a step-over operation
4987 on that particular thread, and leave all others stopped. */
4990 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4992 struct thread_info
*thread
= (struct thread_info
*) entry
;
4993 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5000 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
5005 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
5009 if (thread
->last_resume_kind
== resume_stop
5010 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
5013 debug_printf (" client wants LWP to remain %ld stopped\n",
5018 if (lwp
->status_pending_p
)
5021 debug_printf (" LWP %ld has pending status, leaving stopped\n",
5026 gdb_assert (lwp
->suspended
>= 0);
5031 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
5035 if (thread
->last_resume_kind
== resume_stop
5036 && lwp
->pending_signals_to_report
== NULL
5037 && lwp
->collecting_fast_tracepoint
== 0)
5039 /* We haven't reported this LWP as stopped yet (otherwise, the
5040 last_status.kind check above would catch it, and we wouldn't
5041 reach here. This LWP may have been momentarily paused by a
5042 stop_all_lwps call while handling for example, another LWP's
5043 step-over. In that case, the pending expected SIGSTOP signal
5044 that was queued at vCont;t handling time will have already
5045 been consumed by wait_for_sigstop, and so we need to requeue
5046 another one here. Note that if the LWP already has a SIGSTOP
5047 pending, this is a no-op. */
5050 debug_printf ("Client wants LWP %ld to stop. "
5051 "Making sure it has a SIGSTOP pending\n",
5057 if (thread
->last_resume_kind
== resume_step
)
5060 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5064 else if (lwp
->bp_reinsert
!= 0)
5067 debug_printf (" stepping LWP %ld, reinsert set\n",
5074 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
5079 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
5081 struct thread_info
*thread
= (struct thread_info
*) entry
;
5082 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5087 lwp_suspended_decr (lwp
);
5089 return proceed_one_lwp (entry
, except
);
5092 /* When we finish a step-over, set threads running again. If there's
5093 another thread that may need a step-over, now's the time to start
5094 it. Eventually, we'll move all threads past their breakpoints. */
5097 proceed_all_lwps (void)
5099 struct thread_info
*need_step_over
;
5101 /* If there is a thread which would otherwise be resumed, which is
5102 stopped at a breakpoint that needs stepping over, then don't
5103 resume any threads - have it step over the breakpoint with all
5104 other threads stopped, then resume all threads again. */
5106 if (supports_breakpoints ())
5109 = (struct thread_info
*) find_inferior (&all_threads
,
5110 need_step_over_p
, NULL
);
5112 if (need_step_over
!= NULL
)
5115 debug_printf ("proceed_all_lwps: found "
5116 "thread %ld needing a step-over\n",
5117 lwpid_of (need_step_over
));
5119 start_step_over (get_thread_lwp (need_step_over
));
5125 debug_printf ("Proceeding, no step-over needed\n");
5127 find_inferior (&all_threads
, proceed_one_lwp
, NULL
);
5130 /* Stopped LWPs that the client wanted to be running, that don't have
5131 pending statuses, are set to run again, except for EXCEPT, if not
5132 NULL. This undoes a stop_all_lwps call. */
5135 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
5141 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5142 lwpid_of (get_lwp_thread (except
)));
5144 debug_printf ("unstopping all lwps\n");
5148 find_inferior (&all_threads
, unsuspend_and_proceed_one_lwp
, except
);
5150 find_inferior (&all_threads
, proceed_one_lwp
, except
);
5154 debug_printf ("unstop_all_lwps done\n");
5160 #ifdef HAVE_LINUX_REGSETS
5162 #define use_linux_regsets 1
5164 /* Returns true if REGSET has been disabled. */
5167 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
5169 return (info
->disabled_regsets
!= NULL
5170 && info
->disabled_regsets
[regset
- info
->regsets
]);
5173 /* Disable REGSET. */
5176 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5180 dr_offset
= regset
- info
->regsets
;
5181 if (info
->disabled_regsets
== NULL
)
5182 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5183 info
->disabled_regsets
[dr_offset
] = 1;
5187 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5188 struct regcache
*regcache
)
5190 struct regset_info
*regset
;
5191 int saw_general_regs
= 0;
5195 pid
= lwpid_of (current_thread
);
5196 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5201 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5204 buf
= xmalloc (regset
->size
);
5206 nt_type
= regset
->nt_type
;
5210 iov
.iov_len
= regset
->size
;
5211 data
= (void *) &iov
;
5217 res
= ptrace (regset
->get_request
, pid
,
5218 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5220 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5226 /* If we get EIO on a regset, do not try it again for
5227 this process mode. */
5228 disable_regset (regsets_info
, regset
);
5230 else if (errno
== ENODATA
)
5232 /* ENODATA may be returned if the regset is currently
5233 not "active". This can happen in normal operation,
5234 so suppress the warning in this case. */
5239 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5246 if (regset
->type
== GENERAL_REGS
)
5247 saw_general_regs
= 1;
5248 regset
->store_function (regcache
, buf
);
5252 if (saw_general_regs
)
5259 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5260 struct regcache
*regcache
)
5262 struct regset_info
*regset
;
5263 int saw_general_regs
= 0;
5267 pid
= lwpid_of (current_thread
);
5268 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5273 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5274 || regset
->fill_function
== NULL
)
5277 buf
= xmalloc (regset
->size
);
5279 /* First fill the buffer with the current register set contents,
5280 in case there are any items in the kernel's regset that are
5281 not in gdbserver's regcache. */
5283 nt_type
= regset
->nt_type
;
5287 iov
.iov_len
= regset
->size
;
5288 data
= (void *) &iov
;
5294 res
= ptrace (regset
->get_request
, pid
,
5295 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5297 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5302 /* Then overlay our cached registers on that. */
5303 regset
->fill_function (regcache
, buf
);
5305 /* Only now do we write the register set. */
5307 res
= ptrace (regset
->set_request
, pid
,
5308 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5310 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5318 /* If we get EIO on a regset, do not try it again for
5319 this process mode. */
5320 disable_regset (regsets_info
, regset
);
5322 else if (errno
== ESRCH
)
5324 /* At this point, ESRCH should mean the process is
5325 already gone, in which case we simply ignore attempts
5326 to change its registers. See also the related
5327 comment in linux_resume_one_lwp. */
5333 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5336 else if (regset
->type
== GENERAL_REGS
)
5337 saw_general_regs
= 1;
5340 if (saw_general_regs
)
5346 #else /* !HAVE_LINUX_REGSETS */
5348 #define use_linux_regsets 0
5349 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5350 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5354 /* Return 1 if register REGNO is supported by one of the regset ptrace
5355 calls or 0 if it has to be transferred individually. */
5358 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5360 unsigned char mask
= 1 << (regno
% 8);
5361 size_t index
= regno
/ 8;
5363 return (use_linux_regsets
5364 && (regs_info
->regset_bitmap
== NULL
5365 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5368 #ifdef HAVE_LINUX_USRREGS
5371 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5375 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5376 error ("Invalid register number %d.", regnum
);
5378 addr
= usrregs
->regmap
[regnum
];
5383 /* Fetch one register. */
5385 fetch_register (const struct usrregs_info
*usrregs
,
5386 struct regcache
*regcache
, int regno
)
5393 if (regno
>= usrregs
->num_regs
)
5395 if ((*the_low_target
.cannot_fetch_register
) (regno
))
5398 regaddr
= register_addr (usrregs
, regno
);
5402 size
= ((register_size (regcache
->tdesc
, regno
)
5403 + sizeof (PTRACE_XFER_TYPE
) - 1)
5404 & -sizeof (PTRACE_XFER_TYPE
));
5405 buf
= (char *) alloca (size
);
5407 pid
= lwpid_of (current_thread
);
5408 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5411 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5412 ptrace (PTRACE_PEEKUSER
, pid
,
5413 /* Coerce to a uintptr_t first to avoid potential gcc warning
5414 of coercing an 8 byte integer to a 4 byte pointer. */
5415 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5416 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5418 error ("reading register %d: %s", regno
, strerror (errno
));
5421 if (the_low_target
.supply_ptrace_register
)
5422 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
5424 supply_register (regcache
, regno
, buf
);
5427 /* Store one register. */
5429 store_register (const struct usrregs_info
*usrregs
,
5430 struct regcache
*regcache
, int regno
)
5437 if (regno
>= usrregs
->num_regs
)
5439 if ((*the_low_target
.cannot_store_register
) (regno
))
5442 regaddr
= register_addr (usrregs
, regno
);
5446 size
= ((register_size (regcache
->tdesc
, regno
)
5447 + sizeof (PTRACE_XFER_TYPE
) - 1)
5448 & -sizeof (PTRACE_XFER_TYPE
));
5449 buf
= (char *) alloca (size
);
5450 memset (buf
, 0, size
);
5452 if (the_low_target
.collect_ptrace_register
)
5453 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
5455 collect_register (regcache
, regno
, buf
);
5457 pid
= lwpid_of (current_thread
);
5458 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5461 ptrace (PTRACE_POKEUSER
, pid
,
5462 /* Coerce to a uintptr_t first to avoid potential gcc warning
5463 about coercing an 8 byte integer to a 4 byte pointer. */
5464 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5465 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5468 /* At this point, ESRCH should mean the process is
5469 already gone, in which case we simply ignore attempts
5470 to change its registers. See also the related
5471 comment in linux_resume_one_lwp. */
5475 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
5476 error ("writing register %d: %s", regno
, strerror (errno
));
5478 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5482 /* Fetch all registers, or just one, from the child process.
5483 If REGNO is -1, do this for all registers, skipping any that are
5484 assumed to have been retrieved by regsets_fetch_inferior_registers,
5485 unless ALL is non-zero.
5486 Otherwise, REGNO specifies which register (so we can save time). */
5488 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
5489 struct regcache
*regcache
, int regno
, int all
)
5491 struct usrregs_info
*usr
= regs_info
->usrregs
;
5495 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5496 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5497 fetch_register (usr
, regcache
, regno
);
5500 fetch_register (usr
, regcache
, regno
);
5503 /* Store our register values back into the inferior.
5504 If REGNO is -1, do this for all registers, skipping any that are
5505 assumed to have been saved by regsets_store_inferior_registers,
5506 unless ALL is non-zero.
5507 Otherwise, REGNO specifies which register (so we can save time). */
5509 usr_store_inferior_registers (const struct regs_info
*regs_info
,
5510 struct regcache
*regcache
, int regno
, int all
)
5512 struct usrregs_info
*usr
= regs_info
->usrregs
;
5516 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5517 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5518 store_register (usr
, regcache
, regno
);
5521 store_register (usr
, regcache
, regno
);
5524 #else /* !HAVE_LINUX_USRREGS */
5526 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5527 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5533 linux_fetch_registers (struct regcache
*regcache
, int regno
)
5537 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5541 if (the_low_target
.fetch_register
!= NULL
5542 && regs_info
->usrregs
!= NULL
)
5543 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5544 (*the_low_target
.fetch_register
) (regcache
, regno
);
5546 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5547 if (regs_info
->usrregs
!= NULL
)
5548 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5552 if (the_low_target
.fetch_register
!= NULL
5553 && (*the_low_target
.fetch_register
) (regcache
, regno
))
5556 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5558 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5560 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5561 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5566 linux_store_registers (struct regcache
*regcache
, int regno
)
5570 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5574 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5576 if (regs_info
->usrregs
!= NULL
)
5577 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5581 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5583 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5585 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5586 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5591 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5592 to debugger memory starting at MYADDR. */
5595 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5597 int pid
= lwpid_of (current_thread
);
5598 register PTRACE_XFER_TYPE
*buffer
;
5599 register CORE_ADDR addr
;
5606 /* Try using /proc. Don't bother for one word. */
5607 if (len
>= 3 * sizeof (long))
5611 /* We could keep this file open and cache it - possibly one per
5612 thread. That requires some juggling, but is even faster. */
5613 sprintf (filename
, "/proc/%d/mem", pid
);
5614 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5618 /* If pread64 is available, use it. It's faster if the kernel
5619 supports it (only one syscall), and it's 64-bit safe even on
5620 32-bit platforms (for instance, SPARC debugging a SPARC64
5623 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5626 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5627 bytes
= read (fd
, myaddr
, len
);
5634 /* Some data was read, we'll try to get the rest with ptrace. */
5644 /* Round starting address down to longword boundary. */
5645 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5646 /* Round ending address up; get number of longwords that makes. */
5647 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5648 / sizeof (PTRACE_XFER_TYPE
));
5649 /* Allocate buffer of that many longwords. */
5650 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5652 /* Read all the longwords */
5654 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5656 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5657 about coercing an 8 byte integer to a 4 byte pointer. */
5658 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5659 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5660 (PTRACE_TYPE_ARG4
) 0);
5666 /* Copy appropriate bytes out of the buffer. */
5669 i
*= sizeof (PTRACE_XFER_TYPE
);
5670 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5672 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5679 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5680 memory at MEMADDR. On failure (cannot write to the inferior)
5681 returns the value of errno. Always succeeds if LEN is zero. */
5684 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5687 /* Round starting address down to longword boundary. */
5688 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5689 /* Round ending address up; get number of longwords that makes. */
5691 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5692 / sizeof (PTRACE_XFER_TYPE
);
5694 /* Allocate buffer of that many longwords. */
5695 register PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5697 int pid
= lwpid_of (current_thread
);
5701 /* Zero length write always succeeds. */
5707 /* Dump up to four bytes. */
5708 char str
[4 * 2 + 1];
5710 int dump
= len
< 4 ? len
: 4;
5712 for (i
= 0; i
< dump
; i
++)
5714 sprintf (p
, "%02x", myaddr
[i
]);
5719 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5720 str
, (long) memaddr
, pid
);
5723 /* Fill start and end extra bytes of buffer with existing memory data. */
5726 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5727 about coercing an 8 byte integer to a 4 byte pointer. */
5728 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5729 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5730 (PTRACE_TYPE_ARG4
) 0);
5738 = ptrace (PTRACE_PEEKTEXT
, pid
,
5739 /* Coerce to a uintptr_t first to avoid potential gcc warning
5740 about coercing an 8 byte integer to a 4 byte pointer. */
5741 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5742 * sizeof (PTRACE_XFER_TYPE
)),
5743 (PTRACE_TYPE_ARG4
) 0);
5748 /* Copy data to be written over corresponding part of buffer. */
5750 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5753 /* Write the entire buffer. */
5755 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5758 ptrace (PTRACE_POKETEXT
, pid
,
5759 /* Coerce to a uintptr_t first to avoid potential gcc warning
5760 about coercing an 8 byte integer to a 4 byte pointer. */
5761 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5762 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5771 linux_look_up_symbols (void)
5773 #ifdef USE_THREAD_DB
5774 struct process_info
*proc
= current_process ();
5776 if (proc
->priv
->thread_db
!= NULL
)
5784 linux_request_interrupt (void)
5786 extern unsigned long signal_pid
;
5788 /* Send a SIGINT to the process group. This acts just like the user
5789 typed a ^C on the controlling terminal. */
5790 kill (-signal_pid
, SIGINT
);
5793 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5794 to debugger memory starting at MYADDR. */
5797 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5799 char filename
[PATH_MAX
];
5801 int pid
= lwpid_of (current_thread
);
5803 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5805 fd
= open (filename
, O_RDONLY
);
5809 if (offset
!= (CORE_ADDR
) 0
5810 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5813 n
= read (fd
, myaddr
, len
);
5820 /* These breakpoint and watchpoint related wrapper functions simply
5821 pass on the function call if the target has registered a
5822 corresponding function. */
5825 linux_supports_z_point_type (char z_type
)
5827 return (the_low_target
.supports_z_point_type
!= NULL
5828 && the_low_target
.supports_z_point_type (z_type
));
5832 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5833 int size
, struct raw_breakpoint
*bp
)
5835 if (type
== raw_bkpt_type_sw
)
5836 return insert_memory_breakpoint (bp
);
5837 else if (the_low_target
.insert_point
!= NULL
)
5838 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5840 /* Unsupported (see target.h). */
5845 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5846 int size
, struct raw_breakpoint
*bp
)
5848 if (type
== raw_bkpt_type_sw
)
5849 return remove_memory_breakpoint (bp
);
5850 else if (the_low_target
.remove_point
!= NULL
)
5851 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5853 /* Unsupported (see target.h). */
5857 /* Implement the to_stopped_by_sw_breakpoint target_ops
5861 linux_stopped_by_sw_breakpoint (void)
5863 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5865 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5868 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5872 linux_supports_stopped_by_sw_breakpoint (void)
5874 return USE_SIGTRAP_SIGINFO
;
5877 /* Implement the to_stopped_by_hw_breakpoint target_ops
5881 linux_stopped_by_hw_breakpoint (void)
5883 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5885 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5888 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5892 linux_supports_stopped_by_hw_breakpoint (void)
5894 return USE_SIGTRAP_SIGINFO
;
5897 /* Implement the supports_hardware_single_step target_ops method. */
5900 linux_supports_hardware_single_step (void)
5902 return can_hardware_single_step ();
5906 linux_supports_software_single_step (void)
5908 return can_software_single_step ();
5912 linux_stopped_by_watchpoint (void)
5914 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5916 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5920 linux_stopped_data_address (void)
5922 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5924 return lwp
->stopped_data_address
;
5927 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5928 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5929 && defined(PT_TEXT_END_ADDR)
5931 /* This is only used for targets that define PT_TEXT_ADDR,
5932 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5933 the target has different ways of acquiring this information, like
5936 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5937 to tell gdb about. */
5940 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5942 unsigned long text
, text_end
, data
;
5943 int pid
= lwpid_of (current_thread
);
5947 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5948 (PTRACE_TYPE_ARG4
) 0);
5949 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5950 (PTRACE_TYPE_ARG4
) 0);
5951 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5952 (PTRACE_TYPE_ARG4
) 0);
5956 /* Both text and data offsets produced at compile-time (and so
5957 used by gdb) are relative to the beginning of the program,
5958 with the data segment immediately following the text segment.
5959 However, the actual runtime layout in memory may put the data
5960 somewhere else, so when we send gdb a data base-address, we
5961 use the real data base address and subtract the compile-time
5962 data base-address from it (which is just the length of the
5963 text segment). BSS immediately follows data in both
5966 *data_p
= data
- (text_end
- text
);
5975 linux_qxfer_osdata (const char *annex
,
5976 unsigned char *readbuf
, unsigned const char *writebuf
,
5977 CORE_ADDR offset
, int len
)
5979 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5982 /* Convert a native/host siginfo object, into/from the siginfo in the
5983 layout of the inferiors' architecture. */
5986 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
5990 if (the_low_target
.siginfo_fixup
!= NULL
)
5991 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5993 /* If there was no callback, or the callback didn't do anything,
5994 then just do a straight memcpy. */
5998 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
6000 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
6005 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
6006 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
6010 char inf_siginfo
[sizeof (siginfo_t
)];
6012 if (current_thread
== NULL
)
6015 pid
= lwpid_of (current_thread
);
6018 debug_printf ("%s siginfo for lwp %d.\n",
6019 readbuf
!= NULL
? "Reading" : "Writing",
6022 if (offset
>= sizeof (siginfo
))
6025 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6028 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6029 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6030 inferior with a 64-bit GDBSERVER should look the same as debugging it
6031 with a 32-bit GDBSERVER, we need to convert it. */
6032 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
6034 if (offset
+ len
> sizeof (siginfo
))
6035 len
= sizeof (siginfo
) - offset
;
6037 if (readbuf
!= NULL
)
6038 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
6041 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
6043 /* Convert back to ptrace layout before flushing it out. */
6044 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
6046 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6053 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6054 so we notice when children change state; as the handler for the
6055 sigsuspend in my_waitpid. */
6058 sigchld_handler (int signo
)
6060 int old_errno
= errno
;
6066 /* fprintf is not async-signal-safe, so call write
6068 if (write (2, "sigchld_handler\n",
6069 sizeof ("sigchld_handler\n") - 1) < 0)
6070 break; /* just ignore */
6074 if (target_is_async_p ())
6075 async_file_mark (); /* trigger a linux_wait */
6081 linux_supports_non_stop (void)
6087 linux_async (int enable
)
6089 int previous
= target_is_async_p ();
6092 debug_printf ("linux_async (%d), previous=%d\n",
6095 if (previous
!= enable
)
6098 sigemptyset (&mask
);
6099 sigaddset (&mask
, SIGCHLD
);
6101 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
6105 if (pipe (linux_event_pipe
) == -1)
6107 linux_event_pipe
[0] = -1;
6108 linux_event_pipe
[1] = -1;
6109 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6111 warning ("creating event pipe failed.");
6115 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
6116 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
6118 /* Register the event loop handler. */
6119 add_file_handler (linux_event_pipe
[0],
6120 handle_target_event
, NULL
);
6122 /* Always trigger a linux_wait. */
6127 delete_file_handler (linux_event_pipe
[0]);
6129 close (linux_event_pipe
[0]);
6130 close (linux_event_pipe
[1]);
6131 linux_event_pipe
[0] = -1;
6132 linux_event_pipe
[1] = -1;
6135 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6142 linux_start_non_stop (int nonstop
)
6144 /* Register or unregister from event-loop accordingly. */
6145 linux_async (nonstop
);
6147 if (target_is_async_p () != (nonstop
!= 0))
6154 linux_supports_multi_process (void)
6159 /* Check if fork events are supported. */
6162 linux_supports_fork_events (void)
6164 return linux_supports_tracefork ();
6167 /* Check if vfork events are supported. */
6170 linux_supports_vfork_events (void)
6172 return linux_supports_tracefork ();
6175 /* Check if exec events are supported. */
6178 linux_supports_exec_events (void)
6180 return linux_supports_traceexec ();
6183 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
6184 options for the specified lwp. */
6187 reset_lwp_ptrace_options_callback (struct inferior_list_entry
*entry
,
6190 struct thread_info
*thread
= (struct thread_info
*) entry
;
6191 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6195 /* Stop the lwp so we can modify its ptrace options. */
6196 lwp
->must_set_ptrace_flags
= 1;
6197 linux_stop_lwp (lwp
);
6201 /* Already stopped; go ahead and set the ptrace options. */
6202 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6203 int options
= linux_low_ptrace_options (proc
->attached
);
6205 linux_enable_event_reporting (lwpid_of (thread
), options
);
6206 lwp
->must_set_ptrace_flags
= 0;
6212 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6213 ptrace flags for all inferiors. This is in case the new GDB connection
6214 doesn't support the same set of events that the previous one did. */
6217 linux_handle_new_gdb_connection (void)
6221 /* Request that all the lwps reset their ptrace options. */
6222 find_inferior (&all_threads
, reset_lwp_ptrace_options_callback
, &pid
);
6226 linux_supports_disable_randomization (void)
6228 #ifdef HAVE_PERSONALITY
6236 linux_supports_agent (void)
6242 linux_supports_range_stepping (void)
6244 if (*the_low_target
.supports_range_stepping
== NULL
)
6247 return (*the_low_target
.supports_range_stepping
) ();
6250 /* Enumerate spufs IDs for process PID. */
6252 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
6258 struct dirent
*entry
;
6260 sprintf (path
, "/proc/%ld/fd", pid
);
6261 dir
= opendir (path
);
6266 while ((entry
= readdir (dir
)) != NULL
)
6272 fd
= atoi (entry
->d_name
);
6276 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
6277 if (stat (path
, &st
) != 0)
6279 if (!S_ISDIR (st
.st_mode
))
6282 if (statfs (path
, &stfs
) != 0)
6284 if (stfs
.f_type
!= SPUFS_MAGIC
)
6287 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
6289 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
6299 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6300 object type, using the /proc file system. */
6302 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
6303 unsigned const char *writebuf
,
6304 CORE_ADDR offset
, int len
)
6306 long pid
= lwpid_of (current_thread
);
6311 if (!writebuf
&& !readbuf
)
6319 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
6322 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
6323 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
6328 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
6335 ret
= write (fd
, writebuf
, (size_t) len
);
6337 ret
= read (fd
, readbuf
, (size_t) len
);
6343 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6344 struct target_loadseg
6346 /* Core address to which the segment is mapped. */
6348 /* VMA recorded in the program header. */
6350 /* Size of this segment in memory. */
6354 # if defined PT_GETDSBT
6355 struct target_loadmap
6357 /* Protocol version number, must be zero. */
6359 /* Pointer to the DSBT table, its size, and the DSBT index. */
6360 unsigned *dsbt_table
;
6361 unsigned dsbt_size
, dsbt_index
;
6362 /* Number of segments in this map. */
6364 /* The actual memory map. */
6365 struct target_loadseg segs
[/*nsegs*/];
6367 # define LINUX_LOADMAP PT_GETDSBT
6368 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6369 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6371 struct target_loadmap
6373 /* Protocol version number, must be zero. */
6375 /* Number of segments in this map. */
6377 /* The actual memory map. */
6378 struct target_loadseg segs
[/*nsegs*/];
6380 # define LINUX_LOADMAP PTRACE_GETFDPIC
6381 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6382 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6386 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
6387 unsigned char *myaddr
, unsigned int len
)
6389 int pid
= lwpid_of (current_thread
);
6391 struct target_loadmap
*data
= NULL
;
6392 unsigned int actual_length
, copy_length
;
6394 if (strcmp (annex
, "exec") == 0)
6395 addr
= (int) LINUX_LOADMAP_EXEC
;
6396 else if (strcmp (annex
, "interp") == 0)
6397 addr
= (int) LINUX_LOADMAP_INTERP
;
6401 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6407 actual_length
= sizeof (struct target_loadmap
)
6408 + sizeof (struct target_loadseg
) * data
->nsegs
;
6410 if (offset
< 0 || offset
> actual_length
)
6413 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6414 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6418 # define linux_read_loadmap NULL
6419 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6422 linux_process_qsupported (char **features
, int count
)
6424 if (the_low_target
.process_qsupported
!= NULL
)
6425 the_low_target
.process_qsupported (features
, count
);
6429 linux_supports_catch_syscall (void)
6431 return (the_low_target
.get_syscall_trapinfo
!= NULL
6432 && linux_supports_tracesysgood ());
6436 linux_supports_tracepoints (void)
6438 if (*the_low_target
.supports_tracepoints
== NULL
)
6441 return (*the_low_target
.supports_tracepoints
) ();
6445 linux_read_pc (struct regcache
*regcache
)
6447 if (the_low_target
.get_pc
== NULL
)
6450 return (*the_low_target
.get_pc
) (regcache
);
6454 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
6456 gdb_assert (the_low_target
.set_pc
!= NULL
);
6458 (*the_low_target
.set_pc
) (regcache
, pc
);
6462 linux_thread_stopped (struct thread_info
*thread
)
6464 return get_thread_lwp (thread
)->stopped
;
6467 /* This exposes stop-all-threads functionality to other modules. */
6470 linux_pause_all (int freeze
)
6472 stop_all_lwps (freeze
, NULL
);
6475 /* This exposes unstop-all-threads functionality to other gdbserver
6479 linux_unpause_all (int unfreeze
)
6481 unstop_all_lwps (unfreeze
, NULL
);
6485 linux_prepare_to_access_memory (void)
6487 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6490 linux_pause_all (1);
6495 linux_done_accessing_memory (void)
6497 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6500 linux_unpause_all (1);
6504 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
6505 CORE_ADDR collector
,
6508 CORE_ADDR
*jump_entry
,
6509 CORE_ADDR
*trampoline
,
6510 ULONGEST
*trampoline_size
,
6511 unsigned char *jjump_pad_insn
,
6512 ULONGEST
*jjump_pad_insn_size
,
6513 CORE_ADDR
*adjusted_insn_addr
,
6514 CORE_ADDR
*adjusted_insn_addr_end
,
6517 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
6518 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
6519 jump_entry
, trampoline
, trampoline_size
,
6520 jjump_pad_insn
, jjump_pad_insn_size
,
6521 adjusted_insn_addr
, adjusted_insn_addr_end
,
6525 static struct emit_ops
*
6526 linux_emit_ops (void)
6528 if (the_low_target
.emit_ops
!= NULL
)
6529 return (*the_low_target
.emit_ops
) ();
6535 linux_get_min_fast_tracepoint_insn_len (void)
6537 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
6540 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6543 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6544 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6546 char filename
[PATH_MAX
];
6548 const int auxv_size
= is_elf64
6549 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6550 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6552 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6554 fd
= open (filename
, O_RDONLY
);
6560 while (read (fd
, buf
, auxv_size
) == auxv_size
6561 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6565 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6567 switch (aux
->a_type
)
6570 *phdr_memaddr
= aux
->a_un
.a_val
;
6573 *num_phdr
= aux
->a_un
.a_val
;
6579 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6581 switch (aux
->a_type
)
6584 *phdr_memaddr
= aux
->a_un
.a_val
;
6587 *num_phdr
= aux
->a_un
.a_val
;
6595 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6597 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6598 "phdr_memaddr = %ld, phdr_num = %d",
6599 (long) *phdr_memaddr
, *num_phdr
);
6606 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6609 get_dynamic (const int pid
, const int is_elf64
)
6611 CORE_ADDR phdr_memaddr
, relocation
;
6613 unsigned char *phdr_buf
;
6614 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6616 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6619 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6620 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6622 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6625 /* Compute relocation: it is expected to be 0 for "regular" executables,
6626 non-zero for PIE ones. */
6628 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6631 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6633 if (p
->p_type
== PT_PHDR
)
6634 relocation
= phdr_memaddr
- p
->p_vaddr
;
6638 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6640 if (p
->p_type
== PT_PHDR
)
6641 relocation
= phdr_memaddr
- p
->p_vaddr
;
6644 if (relocation
== -1)
6646 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6647 any real world executables, including PIE executables, have always
6648 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6649 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6650 or present DT_DEBUG anyway (fpc binaries are statically linked).
6652 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6654 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6659 for (i
= 0; i
< num_phdr
; i
++)
6663 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6665 if (p
->p_type
== PT_DYNAMIC
)
6666 return p
->p_vaddr
+ relocation
;
6670 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6672 if (p
->p_type
== PT_DYNAMIC
)
6673 return p
->p_vaddr
+ relocation
;
6680 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6681 can be 0 if the inferior does not yet have the library list initialized.
6682 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6683 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6686 get_r_debug (const int pid
, const int is_elf64
)
6688 CORE_ADDR dynamic_memaddr
;
6689 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6690 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6693 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6694 if (dynamic_memaddr
== 0)
6697 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6701 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6702 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6706 unsigned char buf
[sizeof (Elf64_Xword
)];
6710 #ifdef DT_MIPS_RLD_MAP
6711 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6713 if (linux_read_memory (dyn
->d_un
.d_val
,
6714 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6719 #endif /* DT_MIPS_RLD_MAP */
6720 #ifdef DT_MIPS_RLD_MAP_REL
6721 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6723 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6724 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6729 #endif /* DT_MIPS_RLD_MAP_REL */
6731 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6732 map
= dyn
->d_un
.d_val
;
6734 if (dyn
->d_tag
== DT_NULL
)
6739 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6740 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6744 unsigned char buf
[sizeof (Elf32_Word
)];
6748 #ifdef DT_MIPS_RLD_MAP
6749 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6751 if (linux_read_memory (dyn
->d_un
.d_val
,
6752 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6757 #endif /* DT_MIPS_RLD_MAP */
6758 #ifdef DT_MIPS_RLD_MAP_REL
6759 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6761 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6762 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6767 #endif /* DT_MIPS_RLD_MAP_REL */
6769 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6770 map
= dyn
->d_un
.d_val
;
6772 if (dyn
->d_tag
== DT_NULL
)
6776 dynamic_memaddr
+= dyn_size
;
6782 /* Read one pointer from MEMADDR in the inferior. */
6785 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6789 /* Go through a union so this works on either big or little endian
6790 hosts, when the inferior's pointer size is smaller than the size
6791 of CORE_ADDR. It is assumed the inferior's endianness is the
6792 same of the superior's. */
6795 CORE_ADDR core_addr
;
6800 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6803 if (ptr_size
== sizeof (CORE_ADDR
))
6804 *ptr
= addr
.core_addr
;
6805 else if (ptr_size
== sizeof (unsigned int))
6808 gdb_assert_not_reached ("unhandled pointer size");
6813 struct link_map_offsets
6815 /* Offset and size of r_debug.r_version. */
6816 int r_version_offset
;
6818 /* Offset and size of r_debug.r_map. */
6821 /* Offset to l_addr field in struct link_map. */
6824 /* Offset to l_name field in struct link_map. */
6827 /* Offset to l_ld field in struct link_map. */
6830 /* Offset to l_next field in struct link_map. */
6833 /* Offset to l_prev field in struct link_map. */
6837 /* Construct qXfer:libraries-svr4:read reply. */
6840 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6841 unsigned const char *writebuf
,
6842 CORE_ADDR offset
, int len
)
6845 unsigned document_len
;
6846 struct process_info_private
*const priv
= current_process ()->priv
;
6847 char filename
[PATH_MAX
];
6850 static const struct link_map_offsets lmo_32bit_offsets
=
6852 0, /* r_version offset. */
6853 4, /* r_debug.r_map offset. */
6854 0, /* l_addr offset in link_map. */
6855 4, /* l_name offset in link_map. */
6856 8, /* l_ld offset in link_map. */
6857 12, /* l_next offset in link_map. */
6858 16 /* l_prev offset in link_map. */
6861 static const struct link_map_offsets lmo_64bit_offsets
=
6863 0, /* r_version offset. */
6864 8, /* r_debug.r_map offset. */
6865 0, /* l_addr offset in link_map. */
6866 8, /* l_name offset in link_map. */
6867 16, /* l_ld offset in link_map. */
6868 24, /* l_next offset in link_map. */
6869 32 /* l_prev offset in link_map. */
6871 const struct link_map_offsets
*lmo
;
6872 unsigned int machine
;
6874 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6875 int allocated
= 1024;
6877 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6878 int header_done
= 0;
6880 if (writebuf
!= NULL
)
6882 if (readbuf
== NULL
)
6885 pid
= lwpid_of (current_thread
);
6886 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6887 is_elf64
= elf_64_file_p (filename
, &machine
);
6888 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6889 ptr_size
= is_elf64
? 8 : 4;
6891 while (annex
[0] != '\0')
6897 sep
= strchr (annex
, '=');
6902 if (len
== 5 && startswith (annex
, "start"))
6904 else if (len
== 4 && startswith (annex
, "prev"))
6908 annex
= strchr (sep
, ';');
6915 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6922 if (priv
->r_debug
== 0)
6923 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6925 /* We failed to find DT_DEBUG. Such situation will not change
6926 for this inferior - do not retry it. Report it to GDB as
6927 E01, see for the reasons at the GDB solib-svr4.c side. */
6928 if (priv
->r_debug
== (CORE_ADDR
) -1)
6931 if (priv
->r_debug
!= 0)
6933 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6934 (unsigned char *) &r_version
,
6935 sizeof (r_version
)) != 0
6938 warning ("unexpected r_debug version %d", r_version
);
6940 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6941 &lm_addr
, ptr_size
) != 0)
6943 warning ("unable to read r_map from 0x%lx",
6944 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6949 document
= (char *) xmalloc (allocated
);
6950 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
6951 p
= document
+ strlen (document
);
6954 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6955 &l_name
, ptr_size
) == 0
6956 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6957 &l_addr
, ptr_size
) == 0
6958 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6959 &l_ld
, ptr_size
) == 0
6960 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6961 &l_prev
, ptr_size
) == 0
6962 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6963 &l_next
, ptr_size
) == 0)
6965 unsigned char libname
[PATH_MAX
];
6967 if (lm_prev
!= l_prev
)
6969 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6970 (long) lm_prev
, (long) l_prev
);
6974 /* Ignore the first entry even if it has valid name as the first entry
6975 corresponds to the main executable. The first entry should not be
6976 skipped if the dynamic loader was loaded late by a static executable
6977 (see solib-svr4.c parameter ignore_first). But in such case the main
6978 executable does not have PT_DYNAMIC present and this function already
6979 exited above due to failed get_r_debug. */
6982 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6987 /* Not checking for error because reading may stop before
6988 we've got PATH_MAX worth of characters. */
6990 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6991 libname
[sizeof (libname
) - 1] = '\0';
6992 if (libname
[0] != '\0')
6994 /* 6x the size for xml_escape_text below. */
6995 size_t len
= 6 * strlen ((char *) libname
);
7000 /* Terminate `<library-list-svr4'. */
7005 while (allocated
< p
- document
+ len
+ 200)
7007 /* Expand to guarantee sufficient storage. */
7008 uintptr_t document_len
= p
- document
;
7010 document
= (char *) xrealloc (document
, 2 * allocated
);
7012 p
= document
+ document_len
;
7015 name
= xml_escape_text ((char *) libname
);
7016 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
7017 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
7018 name
, (unsigned long) lm_addr
,
7019 (unsigned long) l_addr
, (unsigned long) l_ld
);
7030 /* Empty list; terminate `<library-list-svr4'. */
7034 strcpy (p
, "</library-list-svr4>");
7036 document_len
= strlen (document
);
7037 if (offset
< document_len
)
7038 document_len
-= offset
;
7041 if (len
> document_len
)
7044 memcpy (readbuf
, document
+ offset
, len
);
7050 #ifdef HAVE_LINUX_BTRACE
7052 /* See to_disable_btrace target method. */
7055 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
7057 enum btrace_error err
;
7059 err
= linux_disable_btrace (tinfo
);
7060 return (err
== BTRACE_ERR_NONE
? 0 : -1);
7063 /* Encode an Intel Processor Trace configuration. */
7066 linux_low_encode_pt_config (struct buffer
*buffer
,
7067 const struct btrace_data_pt_config
*config
)
7069 buffer_grow_str (buffer
, "<pt-config>\n");
7071 switch (config
->cpu
.vendor
)
7074 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7075 "model=\"%u\" stepping=\"%u\"/>\n",
7076 config
->cpu
.family
, config
->cpu
.model
,
7077 config
->cpu
.stepping
);
7084 buffer_grow_str (buffer
, "</pt-config>\n");
7087 /* Encode a raw buffer. */
7090 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
7096 /* We use hex encoding - see common/rsp-low.h. */
7097 buffer_grow_str (buffer
, "<raw>\n");
7103 elem
[0] = tohex ((*data
>> 4) & 0xf);
7104 elem
[1] = tohex (*data
++ & 0xf);
7106 buffer_grow (buffer
, elem
, 2);
7109 buffer_grow_str (buffer
, "</raw>\n");
7112 /* See to_read_btrace target method. */
7115 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
7116 enum btrace_read_type type
)
7118 struct btrace_data btrace
;
7119 struct btrace_block
*block
;
7120 enum btrace_error err
;
7123 btrace_data_init (&btrace
);
7125 err
= linux_read_btrace (&btrace
, tinfo
, type
);
7126 if (err
!= BTRACE_ERR_NONE
)
7128 if (err
== BTRACE_ERR_OVERFLOW
)
7129 buffer_grow_str0 (buffer
, "E.Overflow.");
7131 buffer_grow_str0 (buffer
, "E.Generic Error.");
7136 switch (btrace
.format
)
7138 case BTRACE_FORMAT_NONE
:
7139 buffer_grow_str0 (buffer
, "E.No Trace.");
7142 case BTRACE_FORMAT_BTS
:
7143 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7144 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7147 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
7149 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7150 paddress (block
->begin
), paddress (block
->end
));
7152 buffer_grow_str0 (buffer
, "</btrace>\n");
7155 case BTRACE_FORMAT_PT
:
7156 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7157 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7158 buffer_grow_str (buffer
, "<pt>\n");
7160 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
7162 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
7163 btrace
.variant
.pt
.size
);
7165 buffer_grow_str (buffer
, "</pt>\n");
7166 buffer_grow_str0 (buffer
, "</btrace>\n");
7170 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
7174 btrace_data_fini (&btrace
);
7178 btrace_data_fini (&btrace
);
7182 /* See to_btrace_conf target method. */
7185 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
7186 struct buffer
*buffer
)
7188 const struct btrace_config
*conf
;
7190 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7191 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7193 conf
= linux_btrace_conf (tinfo
);
7196 switch (conf
->format
)
7198 case BTRACE_FORMAT_NONE
:
7201 case BTRACE_FORMAT_BTS
:
7202 buffer_xml_printf (buffer
, "<bts");
7203 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7204 buffer_xml_printf (buffer
, " />\n");
7207 case BTRACE_FORMAT_PT
:
7208 buffer_xml_printf (buffer
, "<pt");
7209 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7210 buffer_xml_printf (buffer
, "/>\n");
7215 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7218 #endif /* HAVE_LINUX_BTRACE */
7220 /* See nat/linux-nat.h. */
7223 current_lwp_ptid (void)
7225 return ptid_of (current_thread
);
7228 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7231 linux_breakpoint_kind_from_pc (CORE_ADDR
*pcptr
)
7233 if (the_low_target
.breakpoint_kind_from_pc
!= NULL
)
7234 return (*the_low_target
.breakpoint_kind_from_pc
) (pcptr
);
7236 return default_breakpoint_kind_from_pc (pcptr
);
7239 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7241 static const gdb_byte
*
7242 linux_sw_breakpoint_from_kind (int kind
, int *size
)
7244 gdb_assert (the_low_target
.sw_breakpoint_from_kind
!= NULL
);
7246 return (*the_low_target
.sw_breakpoint_from_kind
) (kind
, size
);
7249 /* Implementation of the target_ops method
7250 "breakpoint_kind_from_current_state". */
7253 linux_breakpoint_kind_from_current_state (CORE_ADDR
*pcptr
)
7255 if (the_low_target
.breakpoint_kind_from_current_state
!= NULL
)
7256 return (*the_low_target
.breakpoint_kind_from_current_state
) (pcptr
);
7258 return linux_breakpoint_kind_from_pc (pcptr
);
7261 /* Default implementation of linux_target_ops method "set_pc" for
7262 32-bit pc register which is literally named "pc". */
7265 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
7267 uint32_t newpc
= pc
;
7269 supply_register_by_name (regcache
, "pc", &newpc
);
7272 /* Default implementation of linux_target_ops method "get_pc" for
7273 32-bit pc register which is literally named "pc". */
7276 linux_get_pc_32bit (struct regcache
*regcache
)
7280 collect_register_by_name (regcache
, "pc", &pc
);
7282 debug_printf ("stop pc is 0x%" PRIx32
"\n", pc
);
7286 /* Default implementation of linux_target_ops method "set_pc" for
7287 64-bit pc register which is literally named "pc". */
7290 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
7292 uint64_t newpc
= pc
;
7294 supply_register_by_name (regcache
, "pc", &newpc
);
7297 /* Default implementation of linux_target_ops method "get_pc" for
7298 64-bit pc register which is literally named "pc". */
7301 linux_get_pc_64bit (struct regcache
*regcache
)
7305 collect_register_by_name (regcache
, "pc", &pc
);
7307 debug_printf ("stop pc is 0x%" PRIx64
"\n", pc
);
7312 static struct target_ops linux_target_ops
= {
7313 linux_create_inferior
,
7314 linux_post_create_inferior
,
7323 linux_fetch_registers
,
7324 linux_store_registers
,
7325 linux_prepare_to_access_memory
,
7326 linux_done_accessing_memory
,
7329 linux_look_up_symbols
,
7330 linux_request_interrupt
,
7332 linux_supports_z_point_type
,
7335 linux_stopped_by_sw_breakpoint
,
7336 linux_supports_stopped_by_sw_breakpoint
,
7337 linux_stopped_by_hw_breakpoint
,
7338 linux_supports_stopped_by_hw_breakpoint
,
7339 linux_supports_hardware_single_step
,
7340 linux_stopped_by_watchpoint
,
7341 linux_stopped_data_address
,
7342 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7343 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7344 && defined(PT_TEXT_END_ADDR)
7349 #ifdef USE_THREAD_DB
7350 thread_db_get_tls_address
,
7355 hostio_last_error_from_errno
,
7358 linux_supports_non_stop
,
7360 linux_start_non_stop
,
7361 linux_supports_multi_process
,
7362 linux_supports_fork_events
,
7363 linux_supports_vfork_events
,
7364 linux_supports_exec_events
,
7365 linux_handle_new_gdb_connection
,
7366 #ifdef USE_THREAD_DB
7367 thread_db_handle_monitor_command
,
7371 linux_common_core_of_thread
,
7373 linux_process_qsupported
,
7374 linux_supports_tracepoints
,
7377 linux_thread_stopped
,
7381 linux_stabilize_threads
,
7382 linux_install_fast_tracepoint_jump_pad
,
7384 linux_supports_disable_randomization
,
7385 linux_get_min_fast_tracepoint_insn_len
,
7386 linux_qxfer_libraries_svr4
,
7387 linux_supports_agent
,
7388 #ifdef HAVE_LINUX_BTRACE
7389 linux_supports_btrace
,
7390 linux_enable_btrace
,
7391 linux_low_disable_btrace
,
7392 linux_low_read_btrace
,
7393 linux_low_btrace_conf
,
7401 linux_supports_range_stepping
,
7402 linux_proc_pid_to_exec_file
,
7403 linux_mntns_open_cloexec
,
7405 linux_mntns_readlink
,
7406 linux_breakpoint_kind_from_pc
,
7407 linux_sw_breakpoint_from_kind
,
7408 linux_proc_tid_get_name
,
7409 linux_breakpoint_kind_from_current_state
,
7410 linux_supports_software_single_step
,
7411 linux_supports_catch_syscall
,
7414 #ifdef HAVE_LINUX_REGSETS
7416 initialize_regsets_info (struct regsets_info
*info
)
7418 for (info
->num_regsets
= 0;
7419 info
->regsets
[info
->num_regsets
].size
>= 0;
7420 info
->num_regsets
++)
7426 initialize_low (void)
7428 struct sigaction sigchld_action
;
7430 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7431 set_target_ops (&linux_target_ops
);
7433 linux_ptrace_init_warnings ();
7435 sigchld_action
.sa_handler
= sigchld_handler
;
7436 sigemptyset (&sigchld_action
.sa_mask
);
7437 sigchld_action
.sa_flags
= SA_RESTART
;
7438 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7440 initialize_low_arch ();
7442 linux_check_ptrace_features ();