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
532 too. If the fork/clone parent is stepping over a breakpoint,
533 all other threads have been suspended already. Leave the
534 child suspended too. */
535 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
536 || event_lwp
->bp_reinsert
!= 0)
539 debug_printf ("HEW: leaving child suspended\n");
540 child_lwp
->suspended
= 1;
543 parent_proc
= get_thread_process (event_thr
);
544 child_proc
->attached
= parent_proc
->attached
;
545 clone_all_breakpoints (&child_proc
->breakpoints
,
546 &child_proc
->raw_breakpoints
,
547 parent_proc
->breakpoints
);
549 tdesc
= XNEW (struct target_desc
);
550 copy_target_description (tdesc
, parent_proc
->tdesc
);
551 child_proc
->tdesc
= tdesc
;
553 /* Clone arch-specific process data. */
554 if (the_low_target
.new_fork
!= NULL
)
555 the_low_target
.new_fork (parent_proc
, child_proc
);
557 /* Save fork info in the parent thread. */
558 if (event
== PTRACE_EVENT_FORK
)
559 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
560 else if (event
== PTRACE_EVENT_VFORK
)
561 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
563 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
565 /* The status_pending field contains bits denoting the
566 extended event, so when the pending event is handled,
567 the handler will look at lwp->waitstatus. */
568 event_lwp
->status_pending_p
= 1;
569 event_lwp
->status_pending
= wstat
;
571 /* Report the event. */
576 debug_printf ("HEW: Got clone event "
577 "from LWP %ld, new child is LWP %ld\n",
578 lwpid_of (event_thr
), new_pid
);
580 ptid
= ptid_build (pid_of (event_thr
), new_pid
, 0);
581 new_lwp
= add_lwp (ptid
);
583 /* Either we're going to immediately resume the new thread
584 or leave it stopped. linux_resume_one_lwp is a nop if it
585 thinks the thread is currently running, so set this first
586 before calling linux_resume_one_lwp. */
587 new_lwp
->stopped
= 1;
589 /* If we're suspending all threads, leave this one suspended
590 too. If the fork/clone parent is stepping over a breakpoint,
591 all other threads have been suspended already. Leave the
592 child suspended too. */
593 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
594 || event_lwp
->bp_reinsert
!= 0)
595 new_lwp
->suspended
= 1;
597 /* Normally we will get the pending SIGSTOP. But in some cases
598 we might get another signal delivered to the group first.
599 If we do get another signal, be sure not to lose it. */
600 if (WSTOPSIG (status
) != SIGSTOP
)
602 new_lwp
->stop_expected
= 1;
603 new_lwp
->status_pending_p
= 1;
604 new_lwp
->status_pending
= status
;
606 else if (report_thread_events
)
608 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
609 new_lwp
->status_pending_p
= 1;
610 new_lwp
->status_pending
= status
;
613 /* Don't report the event. */
616 else if (event
== PTRACE_EVENT_VFORK_DONE
)
618 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
620 /* Report the event. */
623 else if (event
== PTRACE_EVENT_EXEC
&& report_exec_events
)
625 struct process_info
*proc
;
626 VEC (int) *syscalls_to_catch
;
632 debug_printf ("HEW: Got exec event from LWP %ld\n",
633 lwpid_of (event_thr
));
636 /* Get the event ptid. */
637 event_ptid
= ptid_of (event_thr
);
638 event_pid
= ptid_get_pid (event_ptid
);
640 /* Save the syscall list from the execing process. */
641 proc
= get_thread_process (event_thr
);
642 syscalls_to_catch
= proc
->syscalls_to_catch
;
643 proc
->syscalls_to_catch
= NULL
;
645 /* Delete the execing process and all its threads. */
647 current_thread
= NULL
;
649 /* Create a new process/lwp/thread. */
650 proc
= linux_add_process (event_pid
, 0);
651 event_lwp
= add_lwp (event_ptid
);
652 event_thr
= get_lwp_thread (event_lwp
);
653 gdb_assert (current_thread
== event_thr
);
654 linux_arch_setup_thread (event_thr
);
656 /* Set the event status. */
657 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
658 event_lwp
->waitstatus
.value
.execd_pathname
659 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
661 /* Mark the exec status as pending. */
662 event_lwp
->stopped
= 1;
663 event_lwp
->status_pending_p
= 1;
664 event_lwp
->status_pending
= wstat
;
665 event_thr
->last_resume_kind
= resume_continue
;
666 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
668 /* Update syscall state in the new lwp, effectively mid-syscall too. */
669 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
671 /* Restore the list to catch. Don't rely on the client, which is free
672 to avoid sending a new list when the architecture doesn't change.
673 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
674 proc
->syscalls_to_catch
= syscalls_to_catch
;
676 /* Report the event. */
677 *orig_event_lwp
= event_lwp
;
681 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
684 /* Return the PC as read from the regcache of LWP, without any
688 get_pc (struct lwp_info
*lwp
)
690 struct thread_info
*saved_thread
;
691 struct regcache
*regcache
;
694 if (the_low_target
.get_pc
== NULL
)
697 saved_thread
= current_thread
;
698 current_thread
= get_lwp_thread (lwp
);
700 regcache
= get_thread_regcache (current_thread
, 1);
701 pc
= (*the_low_target
.get_pc
) (regcache
);
704 debug_printf ("pc is 0x%lx\n", (long) pc
);
706 current_thread
= saved_thread
;
710 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
711 Fill *SYSNO with the syscall nr trapped. Fill *SYSRET with the
715 get_syscall_trapinfo (struct lwp_info
*lwp
, int *sysno
, int *sysret
)
717 struct thread_info
*saved_thread
;
718 struct regcache
*regcache
;
720 if (the_low_target
.get_syscall_trapinfo
== NULL
)
722 /* If we cannot get the syscall trapinfo, report an unknown
723 system call number and -ENOSYS return value. */
724 *sysno
= UNKNOWN_SYSCALL
;
729 saved_thread
= current_thread
;
730 current_thread
= get_lwp_thread (lwp
);
732 regcache
= get_thread_regcache (current_thread
, 1);
733 (*the_low_target
.get_syscall_trapinfo
) (regcache
, sysno
, sysret
);
737 debug_printf ("get_syscall_trapinfo sysno %d sysret %d\n",
741 current_thread
= saved_thread
;
744 static int check_stopped_by_watchpoint (struct lwp_info
*child
);
746 /* Called when the LWP stopped for a signal/trap. If it stopped for a
747 trap check what caused it (breakpoint, watchpoint, trace, etc.),
748 and save the result in the LWP's stop_reason field. If it stopped
749 for a breakpoint, decrement the PC if necessary on the lwp's
750 architecture. Returns true if we now have the LWP's stop PC. */
753 save_stop_reason (struct lwp_info
*lwp
)
756 CORE_ADDR sw_breakpoint_pc
;
757 struct thread_info
*saved_thread
;
758 #if USE_SIGTRAP_SIGINFO
762 if (the_low_target
.get_pc
== NULL
)
766 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
768 /* breakpoint_at reads from the current thread. */
769 saved_thread
= current_thread
;
770 current_thread
= get_lwp_thread (lwp
);
772 #if USE_SIGTRAP_SIGINFO
773 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
774 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
776 if (siginfo
.si_signo
== SIGTRAP
)
778 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
)
779 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
781 /* The si_code is ambiguous on this arch -- check debug
783 if (!check_stopped_by_watchpoint (lwp
))
784 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
786 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
788 /* If we determine the LWP stopped for a SW breakpoint,
789 trust it. Particularly don't check watchpoint
790 registers, because at least on s390, we'd find
791 stopped-by-watchpoint as long as there's a watchpoint
793 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
795 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
797 /* This can indicate either a hardware breakpoint or
798 hardware watchpoint. Check debug registers. */
799 if (!check_stopped_by_watchpoint (lwp
))
800 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
802 else if (siginfo
.si_code
== TRAP_TRACE
)
804 /* We may have single stepped an instruction that
805 triggered a watchpoint. In that case, on some
806 architectures (such as x86), instead of TRAP_HWBKPT,
807 si_code indicates TRAP_TRACE, and we need to check
808 the debug registers separately. */
809 if (!check_stopped_by_watchpoint (lwp
))
810 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
815 /* We may have just stepped a breakpoint instruction. E.g., in
816 non-stop mode, GDB first tells the thread A to step a range, and
817 then the user inserts a breakpoint inside the range. In that
818 case we need to report the breakpoint PC. */
819 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
820 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
821 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
823 if (hardware_breakpoint_inserted_here (pc
))
824 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
826 if (lwp
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
)
827 check_stopped_by_watchpoint (lwp
);
830 if (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
834 struct thread_info
*thr
= get_lwp_thread (lwp
);
836 debug_printf ("CSBB: %s stopped by software breakpoint\n",
837 target_pid_to_str (ptid_of (thr
)));
840 /* Back up the PC if necessary. */
841 if (pc
!= sw_breakpoint_pc
)
843 struct regcache
*regcache
844 = get_thread_regcache (current_thread
, 1);
845 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
848 /* Update this so we record the correct stop PC below. */
849 pc
= sw_breakpoint_pc
;
851 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
)
855 struct thread_info
*thr
= get_lwp_thread (lwp
);
857 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
858 target_pid_to_str (ptid_of (thr
)));
861 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
865 struct thread_info
*thr
= get_lwp_thread (lwp
);
867 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
868 target_pid_to_str (ptid_of (thr
)));
871 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
875 struct thread_info
*thr
= get_lwp_thread (lwp
);
877 debug_printf ("CSBB: %s stopped by trace\n",
878 target_pid_to_str (ptid_of (thr
)));
883 current_thread
= saved_thread
;
887 static struct lwp_info
*
888 add_lwp (ptid_t ptid
)
890 struct lwp_info
*lwp
;
892 lwp
= XCNEW (struct lwp_info
);
894 lwp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
896 if (the_low_target
.new_thread
!= NULL
)
897 the_low_target
.new_thread (lwp
);
899 lwp
->thread
= add_thread (ptid
, lwp
);
904 /* Start an inferior process and returns its pid.
905 ALLARGS is a vector of program-name and args. */
908 linux_create_inferior (char *program
, char **allargs
)
910 struct lwp_info
*new_lwp
;
913 struct cleanup
*restore_personality
914 = maybe_disable_address_space_randomization (disable_randomization
);
916 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
922 perror_with_name ("fork");
927 ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
931 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
932 stdout to stderr so that inferior i/o doesn't corrupt the connection.
933 Also, redirect stdin to /dev/null. */
934 if (remote_connection_is_stdio ())
937 open ("/dev/null", O_RDONLY
);
939 if (write (2, "stdin/stdout redirected\n",
940 sizeof ("stdin/stdout redirected\n") - 1) < 0)
942 /* Errors ignored. */;
946 execv (program
, allargs
);
948 execvp (program
, allargs
);
950 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
956 do_cleanups (restore_personality
);
958 linux_add_process (pid
, 0);
960 ptid
= ptid_build (pid
, pid
, 0);
961 new_lwp
= add_lwp (ptid
);
962 new_lwp
->must_set_ptrace_flags
= 1;
967 /* Implement the post_create_inferior target_ops method. */
970 linux_post_create_inferior (void)
972 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
976 if (lwp
->must_set_ptrace_flags
)
978 struct process_info
*proc
= current_process ();
979 int options
= linux_low_ptrace_options (proc
->attached
);
981 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
982 lwp
->must_set_ptrace_flags
= 0;
986 /* Attach to an inferior process. Returns 0 on success, ERRNO on
990 linux_attach_lwp (ptid_t ptid
)
992 struct lwp_info
*new_lwp
;
993 int lwpid
= ptid_get_lwp (ptid
);
995 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
999 new_lwp
= add_lwp (ptid
);
1001 /* We need to wait for SIGSTOP before being able to make the next
1002 ptrace call on this LWP. */
1003 new_lwp
->must_set_ptrace_flags
= 1;
1005 if (linux_proc_pid_is_stopped (lwpid
))
1008 debug_printf ("Attached to a stopped process\n");
1010 /* The process is definitely stopped. It is in a job control
1011 stop, unless the kernel predates the TASK_STOPPED /
1012 TASK_TRACED distinction, in which case it might be in a
1013 ptrace stop. Make sure it is in a ptrace stop; from there we
1014 can kill it, signal it, et cetera.
1016 First make sure there is a pending SIGSTOP. Since we are
1017 already attached, the process can not transition from stopped
1018 to running without a PTRACE_CONT; so we know this signal will
1019 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1020 probably already in the queue (unless this kernel is old
1021 enough to use TASK_STOPPED for ptrace stops); but since
1022 SIGSTOP is not an RT signal, it can only be queued once. */
1023 kill_lwp (lwpid
, SIGSTOP
);
1025 /* Finally, resume the stopped process. This will deliver the
1026 SIGSTOP (or a higher priority signal, just like normal
1027 PTRACE_ATTACH), which we'll catch later on. */
1028 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1031 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1032 brings it to a halt.
1034 There are several cases to consider here:
1036 1) gdbserver has already attached to the process and is being notified
1037 of a new thread that is being created.
1038 In this case we should ignore that SIGSTOP and resume the
1039 process. This is handled below by setting stop_expected = 1,
1040 and the fact that add_thread sets last_resume_kind ==
1043 2) This is the first thread (the process thread), and we're attaching
1044 to it via attach_inferior.
1045 In this case we want the process thread to stop.
1046 This is handled by having linux_attach set last_resume_kind ==
1047 resume_stop after we return.
1049 If the pid we are attaching to is also the tgid, we attach to and
1050 stop all the existing threads. Otherwise, we attach to pid and
1051 ignore any other threads in the same group as this pid.
1053 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1055 In this case we want the thread to stop.
1056 FIXME: This case is currently not properly handled.
1057 We should wait for the SIGSTOP but don't. Things work apparently
1058 because enough time passes between when we ptrace (ATTACH) and when
1059 gdb makes the next ptrace call on the thread.
1061 On the other hand, if we are currently trying to stop all threads, we
1062 should treat the new thread as if we had sent it a SIGSTOP. This works
1063 because we are guaranteed that the add_lwp call above added us to the
1064 end of the list, and so the new thread has not yet reached
1065 wait_for_sigstop (but will). */
1066 new_lwp
->stop_expected
= 1;
1071 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1072 already attached. Returns true if a new LWP is found, false
1076 attach_proc_task_lwp_callback (ptid_t ptid
)
1078 /* Is this a new thread? */
1079 if (find_thread_ptid (ptid
) == NULL
)
1081 int lwpid
= ptid_get_lwp (ptid
);
1085 debug_printf ("Found new lwp %d\n", lwpid
);
1087 err
= linux_attach_lwp (ptid
);
1089 /* Be quiet if we simply raced with the thread exiting. EPERM
1090 is returned if the thread's task still exists, and is marked
1091 as exited or zombie, as well as other conditions, so in that
1092 case, confirm the status in /proc/PID/status. */
1094 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1098 debug_printf ("Cannot attach to lwp %d: "
1099 "thread is gone (%d: %s)\n",
1100 lwpid
, err
, strerror (err
));
1105 warning (_("Cannot attach to lwp %d: %s"),
1107 linux_ptrace_attach_fail_reason_string (ptid
, err
));
1115 static void async_file_mark (void);
1117 /* Attach to PID. If PID is the tgid, attach to it and all
1121 linux_attach (unsigned long pid
)
1123 struct process_info
*proc
;
1124 struct thread_info
*initial_thread
;
1125 ptid_t ptid
= ptid_build (pid
, pid
, 0);
1128 /* Attach to PID. We will check for other threads
1130 err
= linux_attach_lwp (ptid
);
1132 error ("Cannot attach to process %ld: %s",
1133 pid
, linux_ptrace_attach_fail_reason_string (ptid
, err
));
1135 proc
= linux_add_process (pid
, 1);
1137 /* Don't ignore the initial SIGSTOP if we just attached to this
1138 process. It will be collected by wait shortly. */
1139 initial_thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
1140 initial_thread
->last_resume_kind
= resume_stop
;
1142 /* We must attach to every LWP. If /proc is mounted, use that to
1143 find them now. On the one hand, the inferior may be using raw
1144 clone instead of using pthreads. On the other hand, even if it
1145 is using pthreads, GDB may not be connected yet (thread_db needs
1146 to do symbol lookups, through qSymbol). Also, thread_db walks
1147 structures in the inferior's address space to find the list of
1148 threads/LWPs, and those structures may well be corrupted. Note
1149 that once thread_db is loaded, we'll still use it to list threads
1150 and associate pthread info with each LWP. */
1151 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1153 /* GDB will shortly read the xml target description for this
1154 process, to figure out the process' architecture. But the target
1155 description is only filled in when the first process/thread in
1156 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1157 that now, otherwise, if GDB is fast enough, it could read the
1158 target description _before_ that initial stop. */
1161 struct lwp_info
*lwp
;
1163 ptid_t pid_ptid
= pid_to_ptid (pid
);
1165 lwpid
= linux_wait_for_event_filtered (pid_ptid
, pid_ptid
,
1167 gdb_assert (lwpid
> 0);
1169 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
1171 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1173 lwp
->status_pending_p
= 1;
1174 lwp
->status_pending
= wstat
;
1177 initial_thread
->last_resume_kind
= resume_continue
;
1181 gdb_assert (proc
->tdesc
!= NULL
);
1194 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
1196 struct counter
*counter
= (struct counter
*) args
;
1198 if (ptid_get_pid (entry
->id
) == counter
->pid
)
1200 if (++counter
->count
> 1)
1208 last_thread_of_process_p (int pid
)
1210 struct counter counter
= { pid
, 0 };
1212 return (find_inferior (&all_threads
,
1213 second_thread_of_pid_p
, &counter
) == NULL
);
1219 linux_kill_one_lwp (struct lwp_info
*lwp
)
1221 struct thread_info
*thr
= get_lwp_thread (lwp
);
1222 int pid
= lwpid_of (thr
);
1224 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1225 there is no signal context, and ptrace(PTRACE_KILL) (or
1226 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1227 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1228 alternative is to kill with SIGKILL. We only need one SIGKILL
1229 per process, not one for each thread. But since we still support
1230 support debugging programs using raw clone without CLONE_THREAD,
1231 we send one for each thread. For years, we used PTRACE_KILL
1232 only, so we're being a bit paranoid about some old kernels where
1233 PTRACE_KILL might work better (dubious if there are any such, but
1234 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1235 second, and so we're fine everywhere. */
1238 kill_lwp (pid
, SIGKILL
);
1241 int save_errno
= errno
;
1243 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1244 target_pid_to_str (ptid_of (thr
)),
1245 save_errno
? strerror (save_errno
) : "OK");
1249 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1252 int save_errno
= errno
;
1254 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1255 target_pid_to_str (ptid_of (thr
)),
1256 save_errno
? strerror (save_errno
) : "OK");
1260 /* Kill LWP and wait for it to die. */
1263 kill_wait_lwp (struct lwp_info
*lwp
)
1265 struct thread_info
*thr
= get_lwp_thread (lwp
);
1266 int pid
= ptid_get_pid (ptid_of (thr
));
1267 int lwpid
= ptid_get_lwp (ptid_of (thr
));
1272 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1276 linux_kill_one_lwp (lwp
);
1278 /* Make sure it died. Notes:
1280 - The loop is most likely unnecessary.
1282 - We don't use linux_wait_for_event as that could delete lwps
1283 while we're iterating over them. We're not interested in
1284 any pending status at this point, only in making sure all
1285 wait status on the kernel side are collected until the
1288 - We don't use __WALL here as the __WALL emulation relies on
1289 SIGCHLD, and killing a stopped process doesn't generate
1290 one, nor an exit status.
1292 res
= my_waitpid (lwpid
, &wstat
, 0);
1293 if (res
== -1 && errno
== ECHILD
)
1294 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1295 } while (res
> 0 && WIFSTOPPED (wstat
));
1297 /* Even if it was stopped, the child may have already disappeared.
1298 E.g., if it was killed by SIGKILL. */
1299 if (res
< 0 && errno
!= ECHILD
)
1300 perror_with_name ("kill_wait_lwp");
1303 /* Callback for `find_inferior'. Kills an lwp of a given process,
1304 except the leader. */
1307 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
1309 struct thread_info
*thread
= (struct thread_info
*) entry
;
1310 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1311 int pid
= * (int *) args
;
1313 if (ptid_get_pid (entry
->id
) != pid
)
1316 /* We avoid killing the first thread here, because of a Linux kernel (at
1317 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1318 the children get a chance to be reaped, it will remain a zombie
1321 if (lwpid_of (thread
) == pid
)
1324 debug_printf ("lkop: is last of process %s\n",
1325 target_pid_to_str (entry
->id
));
1329 kill_wait_lwp (lwp
);
1334 linux_kill (int pid
)
1336 struct process_info
*process
;
1337 struct lwp_info
*lwp
;
1339 process
= find_process_pid (pid
);
1340 if (process
== NULL
)
1343 /* If we're killing a running inferior, make sure it is stopped
1344 first, as PTRACE_KILL will not work otherwise. */
1345 stop_all_lwps (0, NULL
);
1347 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1349 /* See the comment in linux_kill_one_lwp. We did not kill the first
1350 thread in the list, so do so now. */
1351 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1356 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1360 kill_wait_lwp (lwp
);
1362 the_target
->mourn (process
);
1364 /* Since we presently can only stop all lwps of all processes, we
1365 need to unstop lwps of other processes. */
1366 unstop_all_lwps (0, NULL
);
1370 /* Get pending signal of THREAD, for detaching purposes. This is the
1371 signal the thread last stopped for, which we need to deliver to the
1372 thread when detaching, otherwise, it'd be suppressed/lost. */
1375 get_detach_signal (struct thread_info
*thread
)
1377 enum gdb_signal signo
= GDB_SIGNAL_0
;
1379 struct lwp_info
*lp
= get_thread_lwp (thread
);
1381 if (lp
->status_pending_p
)
1382 status
= lp
->status_pending
;
1385 /* If the thread had been suspended by gdbserver, and it stopped
1386 cleanly, then it'll have stopped with SIGSTOP. But we don't
1387 want to deliver that SIGSTOP. */
1388 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1389 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1392 /* Otherwise, we may need to deliver the signal we
1394 status
= lp
->last_status
;
1397 if (!WIFSTOPPED (status
))
1400 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1401 target_pid_to_str (ptid_of (thread
)));
1405 /* Extended wait statuses aren't real SIGTRAPs. */
1406 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1409 debug_printf ("GPS: lwp %s had stopped with extended "
1410 "status: no pending signal\n",
1411 target_pid_to_str (ptid_of (thread
)));
1415 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1417 if (program_signals_p
&& !program_signals
[signo
])
1420 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1421 target_pid_to_str (ptid_of (thread
)),
1422 gdb_signal_to_string (signo
));
1425 else if (!program_signals_p
1426 /* If we have no way to know which signals GDB does not
1427 want to have passed to the program, assume
1428 SIGTRAP/SIGINT, which is GDB's default. */
1429 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1432 debug_printf ("GPS: lwp %s had signal %s, "
1433 "but we don't know if we should pass it. "
1434 "Default to not.\n",
1435 target_pid_to_str (ptid_of (thread
)),
1436 gdb_signal_to_string (signo
));
1442 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1443 target_pid_to_str (ptid_of (thread
)),
1444 gdb_signal_to_string (signo
));
1446 return WSTOPSIG (status
);
1451 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1453 struct thread_info
*thread
= (struct thread_info
*) entry
;
1454 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1455 int pid
= * (int *) args
;
1458 if (ptid_get_pid (entry
->id
) != pid
)
1461 /* If there is a pending SIGSTOP, get rid of it. */
1462 if (lwp
->stop_expected
)
1465 debug_printf ("Sending SIGCONT to %s\n",
1466 target_pid_to_str (ptid_of (thread
)));
1468 kill_lwp (lwpid_of (thread
), SIGCONT
);
1469 lwp
->stop_expected
= 0;
1472 /* Flush any pending changes to the process's registers. */
1473 regcache_invalidate_thread (thread
);
1475 /* Pass on any pending signal for this thread. */
1476 sig
= get_detach_signal (thread
);
1478 /* Finally, let it resume. */
1479 if (the_low_target
.prepare_to_resume
!= NULL
)
1480 the_low_target
.prepare_to_resume (lwp
);
1481 if (ptrace (PTRACE_DETACH
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1482 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1483 error (_("Can't detach %s: %s"),
1484 target_pid_to_str (ptid_of (thread
)),
1492 linux_detach (int pid
)
1494 struct process_info
*process
;
1496 process
= find_process_pid (pid
);
1497 if (process
== NULL
)
1500 /* As there's a step over already in progress, let it finish first,
1501 otherwise nesting a stabilize_threads operation on top gets real
1503 complete_ongoing_step_over ();
1505 /* Stop all threads before detaching. First, ptrace requires that
1506 the thread is stopped to sucessfully detach. Second, thread_db
1507 may need to uninstall thread event breakpoints from memory, which
1508 only works with a stopped process anyway. */
1509 stop_all_lwps (0, NULL
);
1511 #ifdef USE_THREAD_DB
1512 thread_db_detach (process
);
1515 /* Stabilize threads (move out of jump pads). */
1516 stabilize_threads ();
1518 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1520 the_target
->mourn (process
);
1522 /* Since we presently can only stop all lwps of all processes, we
1523 need to unstop lwps of other processes. */
1524 unstop_all_lwps (0, NULL
);
1528 /* Remove all LWPs that belong to process PROC from the lwp list. */
1531 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1533 struct thread_info
*thread
= (struct thread_info
*) entry
;
1534 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1535 struct process_info
*process
= (struct process_info
*) proc
;
1537 if (pid_of (thread
) == pid_of (process
))
1544 linux_mourn (struct process_info
*process
)
1546 struct process_info_private
*priv
;
1548 #ifdef USE_THREAD_DB
1549 thread_db_mourn (process
);
1552 find_inferior (&all_threads
, delete_lwp_callback
, process
);
1554 /* Freeing all private data. */
1555 priv
= process
->priv
;
1556 free (priv
->arch_private
);
1558 process
->priv
= NULL
;
1560 remove_process (process
);
1564 linux_join (int pid
)
1569 ret
= my_waitpid (pid
, &status
, 0);
1570 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1572 } while (ret
!= -1 || errno
!= ECHILD
);
1575 /* Return nonzero if the given thread is still alive. */
1577 linux_thread_alive (ptid_t ptid
)
1579 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1581 /* We assume we always know if a thread exits. If a whole process
1582 exited but we still haven't been able to report it to GDB, we'll
1583 hold on to the last lwp of the dead process. */
1585 return !lwp_is_marked_dead (lwp
);
1590 /* Return 1 if this lwp still has an interesting status pending. If
1591 not (e.g., it had stopped for a breakpoint that is gone), return
1595 thread_still_has_status_pending_p (struct thread_info
*thread
)
1597 struct lwp_info
*lp
= get_thread_lwp (thread
);
1599 if (!lp
->status_pending_p
)
1602 if (thread
->last_resume_kind
!= resume_stop
1603 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1604 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1606 struct thread_info
*saved_thread
;
1610 gdb_assert (lp
->last_status
!= 0);
1614 saved_thread
= current_thread
;
1615 current_thread
= thread
;
1617 if (pc
!= lp
->stop_pc
)
1620 debug_printf ("PC of %ld changed\n",
1625 #if !USE_SIGTRAP_SIGINFO
1626 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1627 && !(*the_low_target
.breakpoint_at
) (pc
))
1630 debug_printf ("previous SW breakpoint of %ld gone\n",
1634 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1635 && !hardware_breakpoint_inserted_here (pc
))
1638 debug_printf ("previous HW breakpoint of %ld gone\n",
1644 current_thread
= saved_thread
;
1649 debug_printf ("discarding pending breakpoint status\n");
1650 lp
->status_pending_p
= 0;
1658 /* Returns true if LWP is resumed from the client's perspective. */
1661 lwp_resumed (struct lwp_info
*lwp
)
1663 struct thread_info
*thread
= get_lwp_thread (lwp
);
1665 if (thread
->last_resume_kind
!= resume_stop
)
1668 /* Did gdb send us a `vCont;t', but we haven't reported the
1669 corresponding stop to gdb yet? If so, the thread is still
1670 resumed/running from gdb's perspective. */
1671 if (thread
->last_resume_kind
== resume_stop
1672 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1678 /* Return 1 if this lwp has an interesting status pending. */
1680 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1682 struct thread_info
*thread
= (struct thread_info
*) entry
;
1683 struct lwp_info
*lp
= get_thread_lwp (thread
);
1684 ptid_t ptid
= * (ptid_t
*) arg
;
1686 /* Check if we're only interested in events from a specific process
1687 or a specific LWP. */
1688 if (!ptid_match (ptid_of (thread
), ptid
))
1691 if (!lwp_resumed (lp
))
1694 if (lp
->status_pending_p
1695 && !thread_still_has_status_pending_p (thread
))
1697 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1701 return lp
->status_pending_p
;
1705 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1707 ptid_t ptid
= *(ptid_t
*) data
;
1710 if (ptid_get_lwp (ptid
) != 0)
1711 lwp
= ptid_get_lwp (ptid
);
1713 lwp
= ptid_get_pid (ptid
);
1715 if (ptid_get_lwp (entry
->id
) == lwp
)
1722 find_lwp_pid (ptid_t ptid
)
1724 struct inferior_list_entry
*thread
1725 = find_inferior (&all_threads
, same_lwp
, &ptid
);
1730 return get_thread_lwp ((struct thread_info
*) thread
);
1733 /* Return the number of known LWPs in the tgid given by PID. */
1738 struct inferior_list_entry
*inf
, *tmp
;
1741 ALL_INFERIORS (&all_threads
, inf
, tmp
)
1743 if (ptid_get_pid (inf
->id
) == pid
)
1750 /* The arguments passed to iterate_over_lwps. */
1752 struct iterate_over_lwps_args
1754 /* The FILTER argument passed to iterate_over_lwps. */
1757 /* The CALLBACK argument passed to iterate_over_lwps. */
1758 iterate_over_lwps_ftype
*callback
;
1760 /* The DATA argument passed to iterate_over_lwps. */
1764 /* Callback for find_inferior used by iterate_over_lwps to filter
1765 calls to the callback supplied to that function. Returning a
1766 nonzero value causes find_inferiors to stop iterating and return
1767 the current inferior_list_entry. Returning zero indicates that
1768 find_inferiors should continue iterating. */
1771 iterate_over_lwps_filter (struct inferior_list_entry
*entry
, void *args_p
)
1773 struct iterate_over_lwps_args
*args
1774 = (struct iterate_over_lwps_args
*) args_p
;
1776 if (ptid_match (entry
->id
, args
->filter
))
1778 struct thread_info
*thr
= (struct thread_info
*) entry
;
1779 struct lwp_info
*lwp
= get_thread_lwp (thr
);
1781 return (*args
->callback
) (lwp
, args
->data
);
1787 /* See nat/linux-nat.h. */
1790 iterate_over_lwps (ptid_t filter
,
1791 iterate_over_lwps_ftype callback
,
1794 struct iterate_over_lwps_args args
= {filter
, callback
, data
};
1795 struct inferior_list_entry
*entry
;
1797 entry
= find_inferior (&all_threads
, iterate_over_lwps_filter
, &args
);
1801 return get_thread_lwp ((struct thread_info
*) entry
);
1804 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1805 their exits until all other threads in the group have exited. */
1808 check_zombie_leaders (void)
1810 struct process_info
*proc
, *tmp
;
1812 ALL_PROCESSES (proc
, tmp
)
1814 pid_t leader_pid
= pid_of (proc
);
1815 struct lwp_info
*leader_lp
;
1817 leader_lp
= find_lwp_pid (pid_to_ptid (leader_pid
));
1820 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1821 "num_lwps=%d, zombie=%d\n",
1822 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1823 linux_proc_pid_is_zombie (leader_pid
));
1825 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1826 /* Check if there are other threads in the group, as we may
1827 have raced with the inferior simply exiting. */
1828 && !last_thread_of_process_p (leader_pid
)
1829 && linux_proc_pid_is_zombie (leader_pid
))
1831 /* A leader zombie can mean one of two things:
1833 - It exited, and there's an exit status pending
1834 available, or only the leader exited (not the whole
1835 program). In the latter case, we can't waitpid the
1836 leader's exit status until all other threads are gone.
1838 - There are 3 or more threads in the group, and a thread
1839 other than the leader exec'd. On an exec, the Linux
1840 kernel destroys all other threads (except the execing
1841 one) in the thread group, and resets the execing thread's
1842 tid to the tgid. No exit notification is sent for the
1843 execing thread -- from the ptracer's perspective, it
1844 appears as though the execing thread just vanishes.
1845 Until we reap all other threads except the leader and the
1846 execing thread, the leader will be zombie, and the
1847 execing thread will be in `D (disc sleep)'. As soon as
1848 all other threads are reaped, the execing thread changes
1849 it's tid to the tgid, and the previous (zombie) leader
1850 vanishes, giving place to the "new" leader. We could try
1851 distinguishing the exit and exec cases, by waiting once
1852 more, and seeing if something comes out, but it doesn't
1853 sound useful. The previous leader _does_ go away, and
1854 we'll re-add the new one once we see the exec event
1855 (which is just the same as what would happen if the
1856 previous leader did exit voluntarily before some other
1861 "CZL: Thread group leader %d zombie "
1862 "(it exited, or another thread execd).\n",
1865 delete_lwp (leader_lp
);
1870 /* Callback for `find_inferior'. Returns the first LWP that is not
1871 stopped. ARG is a PTID filter. */
1874 not_stopped_callback (struct inferior_list_entry
*entry
, void *arg
)
1876 struct thread_info
*thr
= (struct thread_info
*) entry
;
1877 struct lwp_info
*lwp
;
1878 ptid_t filter
= *(ptid_t
*) arg
;
1880 if (!ptid_match (ptid_of (thr
), filter
))
1883 lwp
= get_thread_lwp (thr
);
1890 /* Increment LWP's suspend count. */
1893 lwp_suspended_inc (struct lwp_info
*lwp
)
1897 if (debug_threads
&& lwp
->suspended
> 4)
1899 struct thread_info
*thread
= get_lwp_thread (lwp
);
1901 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1902 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1906 /* Decrement LWP's suspend count. */
1909 lwp_suspended_decr (struct lwp_info
*lwp
)
1913 if (lwp
->suspended
< 0)
1915 struct thread_info
*thread
= get_lwp_thread (lwp
);
1917 internal_error (__FILE__
, __LINE__
,
1918 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1923 /* This function should only be called if the LWP got a SIGTRAP.
1925 Handle any tracepoint steps or hits. Return true if a tracepoint
1926 event was handled, 0 otherwise. */
1929 handle_tracepoints (struct lwp_info
*lwp
)
1931 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1932 int tpoint_related_event
= 0;
1934 gdb_assert (lwp
->suspended
== 0);
1936 /* If this tracepoint hit causes a tracing stop, we'll immediately
1937 uninsert tracepoints. To do this, we temporarily pause all
1938 threads, unpatch away, and then unpause threads. We need to make
1939 sure the unpausing doesn't resume LWP too. */
1940 lwp_suspended_inc (lwp
);
1942 /* And we need to be sure that any all-threads-stopping doesn't try
1943 to move threads out of the jump pads, as it could deadlock the
1944 inferior (LWP could be in the jump pad, maybe even holding the
1947 /* Do any necessary step collect actions. */
1948 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1950 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1952 /* See if we just hit a tracepoint and do its main collect
1954 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1956 lwp_suspended_decr (lwp
);
1958 gdb_assert (lwp
->suspended
== 0);
1959 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1961 if (tpoint_related_event
)
1964 debug_printf ("got a tracepoint event\n");
1971 /* Convenience wrapper. Returns true if LWP is presently collecting a
1975 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1976 struct fast_tpoint_collect_status
*status
)
1978 CORE_ADDR thread_area
;
1979 struct thread_info
*thread
= get_lwp_thread (lwp
);
1981 if (the_low_target
.get_thread_area
== NULL
)
1984 /* Get the thread area address. This is used to recognize which
1985 thread is which when tracing with the in-process agent library.
1986 We don't read anything from the address, and treat it as opaque;
1987 it's the address itself that we assume is unique per-thread. */
1988 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
1991 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1994 /* The reason we resume in the caller, is because we want to be able
1995 to pass lwp->status_pending as WSTAT, and we need to clear
1996 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1997 refuses to resume. */
2000 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
2002 struct thread_info
*saved_thread
;
2004 saved_thread
= current_thread
;
2005 current_thread
= get_lwp_thread (lwp
);
2008 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
2009 && supports_fast_tracepoints ()
2010 && agent_loaded_p ())
2012 struct fast_tpoint_collect_status status
;
2016 debug_printf ("Checking whether LWP %ld needs to move out of the "
2018 lwpid_of (current_thread
));
2020 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
2023 || (WSTOPSIG (*wstat
) != SIGILL
2024 && WSTOPSIG (*wstat
) != SIGFPE
2025 && WSTOPSIG (*wstat
) != SIGSEGV
2026 && WSTOPSIG (*wstat
) != SIGBUS
))
2028 lwp
->collecting_fast_tracepoint
= r
;
2032 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
2034 /* Haven't executed the original instruction yet.
2035 Set breakpoint there, and wait till it's hit,
2036 then single-step until exiting the jump pad. */
2037 lwp
->exit_jump_pad_bkpt
2038 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
2042 debug_printf ("Checking whether LWP %ld needs to move out of "
2043 "the jump pad...it does\n",
2044 lwpid_of (current_thread
));
2045 current_thread
= saved_thread
;
2052 /* If we get a synchronous signal while collecting, *and*
2053 while executing the (relocated) original instruction,
2054 reset the PC to point at the tpoint address, before
2055 reporting to GDB. Otherwise, it's an IPA lib bug: just
2056 report the signal to GDB, and pray for the best. */
2058 lwp
->collecting_fast_tracepoint
= 0;
2061 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
2062 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2065 struct regcache
*regcache
;
2067 /* The si_addr on a few signals references the address
2068 of the faulting instruction. Adjust that as
2070 if ((WSTOPSIG (*wstat
) == SIGILL
2071 || WSTOPSIG (*wstat
) == SIGFPE
2072 || WSTOPSIG (*wstat
) == SIGBUS
2073 || WSTOPSIG (*wstat
) == SIGSEGV
)
2074 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2075 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2076 /* Final check just to make sure we don't clobber
2077 the siginfo of non-kernel-sent signals. */
2078 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2080 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2081 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2082 (PTRACE_TYPE_ARG3
) 0, &info
);
2085 regcache
= get_thread_regcache (current_thread
, 1);
2086 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
2087 lwp
->stop_pc
= status
.tpoint_addr
;
2089 /* Cancel any fast tracepoint lock this thread was
2091 force_unlock_trace_buffer ();
2094 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2097 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2098 "stopping all threads momentarily.\n");
2100 stop_all_lwps (1, lwp
);
2102 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2103 lwp
->exit_jump_pad_bkpt
= NULL
;
2105 unstop_all_lwps (1, lwp
);
2107 gdb_assert (lwp
->suspended
>= 0);
2113 debug_printf ("Checking whether LWP %ld needs to move out of the "
2115 lwpid_of (current_thread
));
2117 current_thread
= saved_thread
;
2121 /* Enqueue one signal in the "signals to report later when out of the
2125 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2127 struct pending_signals
*p_sig
;
2128 struct thread_info
*thread
= get_lwp_thread (lwp
);
2131 debug_printf ("Deferring signal %d for LWP %ld.\n",
2132 WSTOPSIG (*wstat
), lwpid_of (thread
));
2136 struct pending_signals
*sig
;
2138 for (sig
= lwp
->pending_signals_to_report
;
2141 debug_printf (" Already queued %d\n",
2144 debug_printf (" (no more currently queued signals)\n");
2147 /* Don't enqueue non-RT signals if they are already in the deferred
2148 queue. (SIGSTOP being the easiest signal to see ending up here
2150 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2152 struct pending_signals
*sig
;
2154 for (sig
= lwp
->pending_signals_to_report
;
2158 if (sig
->signal
== WSTOPSIG (*wstat
))
2161 debug_printf ("Not requeuing already queued non-RT signal %d"
2170 p_sig
= XCNEW (struct pending_signals
);
2171 p_sig
->prev
= lwp
->pending_signals_to_report
;
2172 p_sig
->signal
= WSTOPSIG (*wstat
);
2174 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2177 lwp
->pending_signals_to_report
= p_sig
;
2180 /* Dequeue one signal from the "signals to report later when out of
2181 the jump pad" list. */
2184 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2186 struct thread_info
*thread
= get_lwp_thread (lwp
);
2188 if (lwp
->pending_signals_to_report
!= NULL
)
2190 struct pending_signals
**p_sig
;
2192 p_sig
= &lwp
->pending_signals_to_report
;
2193 while ((*p_sig
)->prev
!= NULL
)
2194 p_sig
= &(*p_sig
)->prev
;
2196 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
2197 if ((*p_sig
)->info
.si_signo
!= 0)
2198 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2204 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2205 WSTOPSIG (*wstat
), lwpid_of (thread
));
2209 struct pending_signals
*sig
;
2211 for (sig
= lwp
->pending_signals_to_report
;
2214 debug_printf (" Still queued %d\n",
2217 debug_printf (" (no more queued signals)\n");
2226 /* Fetch the possibly triggered data watchpoint info and store it in
2229 On some archs, like x86, that use debug registers to set
2230 watchpoints, it's possible that the way to know which watched
2231 address trapped, is to check the register that is used to select
2232 which address to watch. Problem is, between setting the watchpoint
2233 and reading back which data address trapped, the user may change
2234 the set of watchpoints, and, as a consequence, GDB changes the
2235 debug registers in the inferior. To avoid reading back a stale
2236 stopped-data-address when that happens, we cache in LP the fact
2237 that a watchpoint trapped, and the corresponding data address, as
2238 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2239 registers meanwhile, we have the cached data we can rely on. */
2242 check_stopped_by_watchpoint (struct lwp_info
*child
)
2244 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2246 struct thread_info
*saved_thread
;
2248 saved_thread
= current_thread
;
2249 current_thread
= get_lwp_thread (child
);
2251 if (the_low_target
.stopped_by_watchpoint ())
2253 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2255 if (the_low_target
.stopped_data_address
!= NULL
)
2256 child
->stopped_data_address
2257 = the_low_target
.stopped_data_address ();
2259 child
->stopped_data_address
= 0;
2262 current_thread
= saved_thread
;
2265 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2268 /* Return the ptrace options that we want to try to enable. */
2271 linux_low_ptrace_options (int attached
)
2276 options
|= PTRACE_O_EXITKILL
;
2278 if (report_fork_events
)
2279 options
|= PTRACE_O_TRACEFORK
;
2281 if (report_vfork_events
)
2282 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2284 if (report_exec_events
)
2285 options
|= PTRACE_O_TRACEEXEC
;
2287 options
|= PTRACE_O_TRACESYSGOOD
;
2292 /* Do low-level handling of the event, and check if we should go on
2293 and pass it to caller code. Return the affected lwp if we are, or
2296 static struct lwp_info
*
2297 linux_low_filter_event (int lwpid
, int wstat
)
2299 struct lwp_info
*child
;
2300 struct thread_info
*thread
;
2301 int have_stop_pc
= 0;
2303 child
= find_lwp_pid (pid_to_ptid (lwpid
));
2305 /* Check for stop events reported by a process we didn't already
2306 know about - anything not already in our LWP list.
2308 If we're expecting to receive stopped processes after
2309 fork, vfork, and clone events, then we'll just add the
2310 new one to our list and go back to waiting for the event
2311 to be reported - the stopped process might be returned
2312 from waitpid before or after the event is.
2314 But note the case of a non-leader thread exec'ing after the
2315 leader having exited, and gone from our lists (because
2316 check_zombie_leaders deleted it). The non-leader thread
2317 changes its tid to the tgid. */
2319 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2320 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2324 /* A multi-thread exec after we had seen the leader exiting. */
2327 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2328 "after exec.\n", lwpid
);
2331 child_ptid
= ptid_build (lwpid
, lwpid
, 0);
2332 child
= add_lwp (child_ptid
);
2334 current_thread
= child
->thread
;
2337 /* If we didn't find a process, one of two things presumably happened:
2338 - A process we started and then detached from has exited. Ignore it.
2339 - A process we are controlling has forked and the new child's stop
2340 was reported to us by the kernel. Save its PID. */
2341 if (child
== NULL
&& WIFSTOPPED (wstat
))
2343 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2346 else if (child
== NULL
)
2349 thread
= get_lwp_thread (child
);
2353 child
->last_status
= wstat
;
2355 /* Check if the thread has exited. */
2356 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2359 debug_printf ("LLFE: %d exited.\n", lwpid
);
2360 /* If there is at least one more LWP, then the exit signal was
2361 not the end of the debugged application and should be
2362 ignored, unless GDB wants to hear about thread exits. */
2363 if (report_thread_events
2364 || last_thread_of_process_p (pid_of (thread
)))
2366 /* Since events are serialized to GDB core, and we can't
2367 report this one right now. Leave the status pending for
2368 the next time we're able to report it. */
2369 mark_lwp_dead (child
, wstat
);
2379 gdb_assert (WIFSTOPPED (wstat
));
2381 if (WIFSTOPPED (wstat
))
2383 struct process_info
*proc
;
2385 /* Architecture-specific setup after inferior is running. */
2386 proc
= find_process_pid (pid_of (thread
));
2387 if (proc
->tdesc
== NULL
)
2391 /* This needs to happen after we have attached to the
2392 inferior and it is stopped for the first time, but
2393 before we access any inferior registers. */
2394 linux_arch_setup_thread (thread
);
2398 /* The process is started, but GDBserver will do
2399 architecture-specific setup after the program stops at
2400 the first instruction. */
2401 child
->status_pending_p
= 1;
2402 child
->status_pending
= wstat
;
2408 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2410 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2411 int options
= linux_low_ptrace_options (proc
->attached
);
2413 linux_enable_event_reporting (lwpid
, options
);
2414 child
->must_set_ptrace_flags
= 0;
2417 /* Always update syscall_state, even if it will be filtered later. */
2418 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SYSCALL_SIGTRAP
)
2420 child
->syscall_state
2421 = (child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2422 ? TARGET_WAITKIND_SYSCALL_RETURN
2423 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2427 /* Almost all other ptrace-stops are known to be outside of system
2428 calls, with further exceptions in handle_extended_wait. */
2429 child
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2432 /* Be careful to not overwrite stop_pc until save_stop_reason is
2434 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2435 && linux_is_extended_waitstatus (wstat
))
2437 child
->stop_pc
= get_pc (child
);
2438 if (handle_extended_wait (&child
, wstat
))
2440 /* The event has been handled, so just return without
2446 if (linux_wstatus_maybe_breakpoint (wstat
))
2448 if (save_stop_reason (child
))
2453 child
->stop_pc
= get_pc (child
);
2455 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2456 && child
->stop_expected
)
2459 debug_printf ("Expected stop.\n");
2460 child
->stop_expected
= 0;
2462 if (thread
->last_resume_kind
== resume_stop
)
2464 /* We want to report the stop to the core. Treat the
2465 SIGSTOP as a normal event. */
2467 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2468 target_pid_to_str (ptid_of (thread
)));
2470 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2472 /* Stopping threads. We don't want this SIGSTOP to end up
2475 debug_printf ("LLW: SIGSTOP caught for %s "
2476 "while stopping threads.\n",
2477 target_pid_to_str (ptid_of (thread
)));
2482 /* This is a delayed SIGSTOP. Filter out the event. */
2484 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2485 child
->stepping
? "step" : "continue",
2486 target_pid_to_str (ptid_of (thread
)));
2488 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2493 child
->status_pending_p
= 1;
2494 child
->status_pending
= wstat
;
2498 /* Resume LWPs that are currently stopped without any pending status
2499 to report, but are resumed from the core's perspective. */
2502 resume_stopped_resumed_lwps (struct inferior_list_entry
*entry
)
2504 struct thread_info
*thread
= (struct thread_info
*) entry
;
2505 struct lwp_info
*lp
= get_thread_lwp (thread
);
2509 && !lp
->status_pending_p
2510 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2512 int step
= thread
->last_resume_kind
== resume_step
;
2515 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2516 target_pid_to_str (ptid_of (thread
)),
2517 paddress (lp
->stop_pc
),
2520 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2524 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2525 match FILTER_PTID (leaving others pending). The PTIDs can be:
2526 minus_one_ptid, to specify any child; a pid PTID, specifying all
2527 lwps of a thread group; or a PTID representing a single lwp. Store
2528 the stop status through the status pointer WSTAT. OPTIONS is
2529 passed to the waitpid call. Return 0 if no event was found and
2530 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2531 was found. Return the PID of the stopped child otherwise. */
2534 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2535 int *wstatp
, int options
)
2537 struct thread_info
*event_thread
;
2538 struct lwp_info
*event_child
, *requested_child
;
2539 sigset_t block_mask
, prev_mask
;
2542 /* N.B. event_thread points to the thread_info struct that contains
2543 event_child. Keep them in sync. */
2544 event_thread
= NULL
;
2546 requested_child
= NULL
;
2548 /* Check for a lwp with a pending status. */
2550 if (ptid_equal (filter_ptid
, minus_one_ptid
) || ptid_is_pid (filter_ptid
))
2552 event_thread
= (struct thread_info
*)
2553 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2554 if (event_thread
!= NULL
)
2555 event_child
= get_thread_lwp (event_thread
);
2556 if (debug_threads
&& event_thread
)
2557 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2559 else if (!ptid_equal (filter_ptid
, null_ptid
))
2561 requested_child
= find_lwp_pid (filter_ptid
);
2563 if (stopping_threads
== NOT_STOPPING_THREADS
2564 && requested_child
->status_pending_p
2565 && requested_child
->collecting_fast_tracepoint
)
2567 enqueue_one_deferred_signal (requested_child
,
2568 &requested_child
->status_pending
);
2569 requested_child
->status_pending_p
= 0;
2570 requested_child
->status_pending
= 0;
2571 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2574 if (requested_child
->suspended
2575 && requested_child
->status_pending_p
)
2577 internal_error (__FILE__
, __LINE__
,
2578 "requesting an event out of a"
2579 " suspended child?");
2582 if (requested_child
->status_pending_p
)
2584 event_child
= requested_child
;
2585 event_thread
= get_lwp_thread (event_child
);
2589 if (event_child
!= NULL
)
2592 debug_printf ("Got an event from pending child %ld (%04x)\n",
2593 lwpid_of (event_thread
), event_child
->status_pending
);
2594 *wstatp
= event_child
->status_pending
;
2595 event_child
->status_pending_p
= 0;
2596 event_child
->status_pending
= 0;
2597 current_thread
= event_thread
;
2598 return lwpid_of (event_thread
);
2601 /* But if we don't find a pending event, we'll have to wait.
2603 We only enter this loop if no process has a pending wait status.
2604 Thus any action taken in response to a wait status inside this
2605 loop is responding as soon as we detect the status, not after any
2608 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2609 all signals while here. */
2610 sigfillset (&block_mask
);
2611 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2613 /* Always pull all events out of the kernel. We'll randomly select
2614 an event LWP out of all that have events, to prevent
2616 while (event_child
== NULL
)
2620 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2623 - If the thread group leader exits while other threads in the
2624 thread group still exist, waitpid(TGID, ...) hangs. That
2625 waitpid won't return an exit status until the other threads
2626 in the group are reaped.
2628 - When a non-leader thread execs, that thread just vanishes
2629 without reporting an exit (so we'd hang if we waited for it
2630 explicitly in that case). The exec event is reported to
2633 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2636 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2637 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2643 debug_printf ("LLW: waitpid %ld received %s\n",
2644 (long) ret
, status_to_str (*wstatp
));
2647 /* Filter all events. IOW, leave all events pending. We'll
2648 randomly select an event LWP out of all that have events
2650 linux_low_filter_event (ret
, *wstatp
);
2651 /* Retry until nothing comes out of waitpid. A single
2652 SIGCHLD can indicate more than one child stopped. */
2656 /* Now that we've pulled all events out of the kernel, resume
2657 LWPs that don't have an interesting event to report. */
2658 if (stopping_threads
== NOT_STOPPING_THREADS
)
2659 for_each_inferior (&all_threads
, resume_stopped_resumed_lwps
);
2661 /* ... and find an LWP with a status to report to the core, if
2663 event_thread
= (struct thread_info
*)
2664 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2665 if (event_thread
!= NULL
)
2667 event_child
= get_thread_lwp (event_thread
);
2668 *wstatp
= event_child
->status_pending
;
2669 event_child
->status_pending_p
= 0;
2670 event_child
->status_pending
= 0;
2674 /* Check for zombie thread group leaders. Those can't be reaped
2675 until all other threads in the thread group are. */
2676 check_zombie_leaders ();
2678 /* If there are no resumed children left in the set of LWPs we
2679 want to wait for, bail. We can't just block in
2680 waitpid/sigsuspend, because lwps might have been left stopped
2681 in trace-stop state, and we'd be stuck forever waiting for
2682 their status to change (which would only happen if we resumed
2683 them). Even if WNOHANG is set, this return code is preferred
2684 over 0 (below), as it is more detailed. */
2685 if ((find_inferior (&all_threads
,
2686 not_stopped_callback
,
2687 &wait_ptid
) == NULL
))
2690 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2691 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2695 /* No interesting event to report to the caller. */
2696 if ((options
& WNOHANG
))
2699 debug_printf ("WNOHANG set, no event found\n");
2701 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2705 /* Block until we get an event reported with SIGCHLD. */
2707 debug_printf ("sigsuspend'ing\n");
2709 sigsuspend (&prev_mask
);
2710 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2714 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2716 current_thread
= event_thread
;
2718 return lwpid_of (event_thread
);
2721 /* Wait for an event from child(ren) PTID. PTIDs can be:
2722 minus_one_ptid, to specify any child; a pid PTID, specifying all
2723 lwps of a thread group; or a PTID representing a single lwp. Store
2724 the stop status through the status pointer WSTAT. OPTIONS is
2725 passed to the waitpid call. Return 0 if no event was found and
2726 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2727 was found. Return the PID of the stopped child otherwise. */
2730 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2732 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2735 /* Count the LWP's that have had events. */
2738 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2740 struct thread_info
*thread
= (struct thread_info
*) entry
;
2741 struct lwp_info
*lp
= get_thread_lwp (thread
);
2742 int *count
= (int *) data
;
2744 gdb_assert (count
!= NULL
);
2746 /* Count only resumed LWPs that have an event pending. */
2747 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2748 && lp
->status_pending_p
)
2754 /* Select the LWP (if any) that is currently being single-stepped. */
2757 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2759 struct thread_info
*thread
= (struct thread_info
*) entry
;
2760 struct lwp_info
*lp
= get_thread_lwp (thread
);
2762 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2763 && thread
->last_resume_kind
== resume_step
2764 && lp
->status_pending_p
)
2770 /* Select the Nth LWP that has had an event. */
2773 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2775 struct thread_info
*thread
= (struct thread_info
*) entry
;
2776 struct lwp_info
*lp
= get_thread_lwp (thread
);
2777 int *selector
= (int *) data
;
2779 gdb_assert (selector
!= NULL
);
2781 /* Select only resumed LWPs that have an event pending. */
2782 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2783 && lp
->status_pending_p
)
2784 if ((*selector
)-- == 0)
2790 /* Select one LWP out of those that have events pending. */
2793 select_event_lwp (struct lwp_info
**orig_lp
)
2796 int random_selector
;
2797 struct thread_info
*event_thread
= NULL
;
2799 /* In all-stop, give preference to the LWP that is being
2800 single-stepped. There will be at most one, and it's the LWP that
2801 the core is most interested in. If we didn't do this, then we'd
2802 have to handle pending step SIGTRAPs somehow in case the core
2803 later continues the previously-stepped thread, otherwise we'd
2804 report the pending SIGTRAP, and the core, not having stepped the
2805 thread, wouldn't understand what the trap was for, and therefore
2806 would report it to the user as a random signal. */
2810 = (struct thread_info
*) find_inferior (&all_threads
,
2811 select_singlestep_lwp_callback
,
2813 if (event_thread
!= NULL
)
2816 debug_printf ("SEL: Select single-step %s\n",
2817 target_pid_to_str (ptid_of (event_thread
)));
2820 if (event_thread
== NULL
)
2822 /* No single-stepping LWP. Select one at random, out of those
2823 which have had events. */
2825 /* First see how many events we have. */
2826 find_inferior (&all_threads
, count_events_callback
, &num_events
);
2827 gdb_assert (num_events
> 0);
2829 /* Now randomly pick a LWP out of those that have had
2831 random_selector
= (int)
2832 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2834 if (debug_threads
&& num_events
> 1)
2835 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2836 num_events
, random_selector
);
2839 = (struct thread_info
*) find_inferior (&all_threads
,
2840 select_event_lwp_callback
,
2844 if (event_thread
!= NULL
)
2846 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2848 /* Switch the event LWP. */
2849 *orig_lp
= event_lp
;
2853 /* Decrement the suspend count of an LWP. */
2856 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2858 struct thread_info
*thread
= (struct thread_info
*) entry
;
2859 struct lwp_info
*lwp
= get_thread_lwp (thread
);
2861 /* Ignore EXCEPT. */
2865 lwp_suspended_decr (lwp
);
2869 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2873 unsuspend_all_lwps (struct lwp_info
*except
)
2875 find_inferior (&all_threads
, unsuspend_one_lwp
, except
);
2878 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2879 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2881 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2882 static ptid_t
linux_wait_1 (ptid_t ptid
,
2883 struct target_waitstatus
*ourstatus
,
2884 int target_options
);
2886 /* Stabilize threads (move out of jump pads).
2888 If a thread is midway collecting a fast tracepoint, we need to
2889 finish the collection and move it out of the jump pad before
2890 reporting the signal.
2892 This avoids recursion while collecting (when a signal arrives
2893 midway, and the signal handler itself collects), which would trash
2894 the trace buffer. In case the user set a breakpoint in a signal
2895 handler, this avoids the backtrace showing the jump pad, etc..
2896 Most importantly, there are certain things we can't do safely if
2897 threads are stopped in a jump pad (or in its callee's). For
2900 - starting a new trace run. A thread still collecting the
2901 previous run, could trash the trace buffer when resumed. The trace
2902 buffer control structures would have been reset but the thread had
2903 no way to tell. The thread could even midway memcpy'ing to the
2904 buffer, which would mean that when resumed, it would clobber the
2905 trace buffer that had been set for a new run.
2907 - we can't rewrite/reuse the jump pads for new tracepoints
2908 safely. Say you do tstart while a thread is stopped midway while
2909 collecting. When the thread is later resumed, it finishes the
2910 collection, and returns to the jump pad, to execute the original
2911 instruction that was under the tracepoint jump at the time the
2912 older run had been started. If the jump pad had been rewritten
2913 since for something else in the new run, the thread would now
2914 execute the wrong / random instructions. */
2917 linux_stabilize_threads (void)
2919 struct thread_info
*saved_thread
;
2920 struct thread_info
*thread_stuck
;
2923 = (struct thread_info
*) find_inferior (&all_threads
,
2924 stuck_in_jump_pad_callback
,
2926 if (thread_stuck
!= NULL
)
2929 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2930 lwpid_of (thread_stuck
));
2934 saved_thread
= current_thread
;
2936 stabilizing_threads
= 1;
2939 for_each_inferior (&all_threads
, move_out_of_jump_pad_callback
);
2941 /* Loop until all are stopped out of the jump pads. */
2942 while (find_inferior (&all_threads
, lwp_running
, NULL
) != NULL
)
2944 struct target_waitstatus ourstatus
;
2945 struct lwp_info
*lwp
;
2948 /* Note that we go through the full wait even loop. While
2949 moving threads out of jump pad, we need to be able to step
2950 over internal breakpoints and such. */
2951 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2953 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2955 lwp
= get_thread_lwp (current_thread
);
2958 lwp_suspended_inc (lwp
);
2960 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2961 || current_thread
->last_resume_kind
== resume_stop
)
2963 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2964 enqueue_one_deferred_signal (lwp
, &wstat
);
2969 find_inferior (&all_threads
, unsuspend_one_lwp
, NULL
);
2971 stabilizing_threads
= 0;
2973 current_thread
= saved_thread
;
2978 = (struct thread_info
*) find_inferior (&all_threads
,
2979 stuck_in_jump_pad_callback
,
2981 if (thread_stuck
!= NULL
)
2982 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2983 lwpid_of (thread_stuck
));
2987 /* Convenience function that is called when the kernel reports an
2988 event that is not passed out to GDB. */
2991 ignore_event (struct target_waitstatus
*ourstatus
)
2993 /* If we got an event, there may still be others, as a single
2994 SIGCHLD can indicate more than one child stopped. This forces
2995 another target_wait call. */
2998 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3002 /* Convenience function that is called when the kernel reports an exit
3003 event. This decides whether to report the event to GDB as a
3004 process exit event, a thread exit event, or to suppress the
3008 filter_exit_event (struct lwp_info
*event_child
,
3009 struct target_waitstatus
*ourstatus
)
3011 struct thread_info
*thread
= get_lwp_thread (event_child
);
3012 ptid_t ptid
= ptid_of (thread
);
3014 if (!last_thread_of_process_p (pid_of (thread
)))
3016 if (report_thread_events
)
3017 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
3019 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3021 delete_lwp (event_child
);
3026 /* Returns 1 if GDB is interested in any event_child syscalls. */
3029 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
3031 struct thread_info
*thread
= get_lwp_thread (event_child
);
3032 struct process_info
*proc
= get_thread_process (thread
);
3034 return !VEC_empty (int, proc
->syscalls_to_catch
);
3037 /* Returns 1 if GDB is interested in the event_child syscall.
3038 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
3041 gdb_catch_this_syscall_p (struct lwp_info
*event_child
)
3045 struct thread_info
*thread
= get_lwp_thread (event_child
);
3046 struct process_info
*proc
= get_thread_process (thread
);
3048 if (VEC_empty (int, proc
->syscalls_to_catch
))
3051 if (VEC_index (int, proc
->syscalls_to_catch
, 0) == ANY_SYSCALL
)
3054 get_syscall_trapinfo (event_child
, &sysno
, &sysret
);
3056 VEC_iterate (int, proc
->syscalls_to_catch
, i
, iter
);
3064 /* Wait for process, returns status. */
3067 linux_wait_1 (ptid_t ptid
,
3068 struct target_waitstatus
*ourstatus
, int target_options
)
3071 struct lwp_info
*event_child
;
3074 int step_over_finished
;
3075 int bp_explains_trap
;
3076 int maybe_internal_trap
;
3085 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
3088 /* Translate generic target options into linux options. */
3090 if (target_options
& TARGET_WNOHANG
)
3093 bp_explains_trap
= 0;
3096 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3098 /* Find a resumed LWP, if any. */
3099 if (find_inferior (&all_threads
,
3100 status_pending_p_callback
,
3101 &minus_one_ptid
) != NULL
)
3103 else if ((find_inferior (&all_threads
,
3104 not_stopped_callback
,
3105 &minus_one_ptid
) != NULL
))
3110 if (ptid_equal (step_over_bkpt
, null_ptid
))
3111 pid
= linux_wait_for_event (ptid
, &w
, options
);
3115 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3116 target_pid_to_str (step_over_bkpt
));
3117 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
3120 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3122 gdb_assert (target_options
& TARGET_WNOHANG
);
3126 debug_printf ("linux_wait_1 ret = null_ptid, "
3127 "TARGET_WAITKIND_IGNORE\n");
3131 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3138 debug_printf ("linux_wait_1 ret = null_ptid, "
3139 "TARGET_WAITKIND_NO_RESUMED\n");
3143 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3147 event_child
= get_thread_lwp (current_thread
);
3149 /* linux_wait_for_event only returns an exit status for the last
3150 child of a process. Report it. */
3151 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3155 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3156 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3160 debug_printf ("linux_wait_1 ret = %s, exited with "
3162 target_pid_to_str (ptid_of (current_thread
)),
3169 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3170 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3174 debug_printf ("linux_wait_1 ret = %s, terminated with "
3176 target_pid_to_str (ptid_of (current_thread
)),
3182 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3183 return filter_exit_event (event_child
, ourstatus
);
3185 return ptid_of (current_thread
);
3188 /* If step-over executes a breakpoint instruction, in the case of a
3189 hardware single step it means a gdb/gdbserver breakpoint had been
3190 planted on top of a permanent breakpoint, in the case of a software
3191 single step it may just mean that gdbserver hit the reinsert breakpoint.
3192 The PC has been adjusted by save_stop_reason to point at
3193 the breakpoint address.
3194 So in the case of the hardware single step advance the PC manually
3195 past the breakpoint and in the case of software single step advance only
3196 if it's not the reinsert_breakpoint we are hitting.
3197 This avoids that a program would keep trapping a permanent breakpoint
3199 if (!ptid_equal (step_over_bkpt
, null_ptid
)
3200 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3201 && (event_child
->stepping
3202 || !reinsert_breakpoint_inserted_here (event_child
->stop_pc
)))
3204 int increment_pc
= 0;
3205 int breakpoint_kind
= 0;
3206 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3209 the_target
->breakpoint_kind_from_current_state (&stop_pc
);
3210 the_target
->sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3214 debug_printf ("step-over for %s executed software breakpoint\n",
3215 target_pid_to_str (ptid_of (current_thread
)));
3218 if (increment_pc
!= 0)
3220 struct regcache
*regcache
3221 = get_thread_regcache (current_thread
, 1);
3223 event_child
->stop_pc
+= increment_pc
;
3224 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3226 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
3227 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3231 /* If this event was not handled before, and is not a SIGTRAP, we
3232 report it. SIGILL and SIGSEGV are also treated as traps in case
3233 a breakpoint is inserted at the current PC. If this target does
3234 not support internal breakpoints at all, we also report the
3235 SIGTRAP without further processing; it's of no concern to us. */
3237 = (supports_breakpoints ()
3238 && (WSTOPSIG (w
) == SIGTRAP
3239 || ((WSTOPSIG (w
) == SIGILL
3240 || WSTOPSIG (w
) == SIGSEGV
)
3241 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
3243 if (maybe_internal_trap
)
3245 /* Handle anything that requires bookkeeping before deciding to
3246 report the event or continue waiting. */
3248 /* First check if we can explain the SIGTRAP with an internal
3249 breakpoint, or if we should possibly report the event to GDB.
3250 Do this before anything that may remove or insert a
3252 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3254 /* We have a SIGTRAP, possibly a step-over dance has just
3255 finished. If so, tweak the state machine accordingly,
3256 reinsert breakpoints and delete any reinsert (software
3257 single-step) breakpoints. */
3258 step_over_finished
= finish_step_over (event_child
);
3260 /* Now invoke the callbacks of any internal breakpoints there. */
3261 check_breakpoints (event_child
->stop_pc
);
3263 /* Handle tracepoint data collecting. This may overflow the
3264 trace buffer, and cause a tracing stop, removing
3266 trace_event
= handle_tracepoints (event_child
);
3268 if (bp_explains_trap
)
3270 /* If we stepped or ran into an internal breakpoint, we've
3271 already handled it. So next time we resume (from this
3272 PC), we should step over it. */
3274 debug_printf ("Hit a gdbserver breakpoint.\n");
3276 if (breakpoint_here (event_child
->stop_pc
))
3277 event_child
->need_step_over
= 1;
3282 /* We have some other signal, possibly a step-over dance was in
3283 progress, and it should be cancelled too. */
3284 step_over_finished
= finish_step_over (event_child
);
3287 /* We have all the data we need. Either report the event to GDB, or
3288 resume threads and keep waiting for more. */
3290 /* If we're collecting a fast tracepoint, finish the collection and
3291 move out of the jump pad before delivering a signal. See
3292 linux_stabilize_threads. */
3295 && WSTOPSIG (w
) != SIGTRAP
3296 && supports_fast_tracepoints ()
3297 && agent_loaded_p ())
3300 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3301 "to defer or adjust it.\n",
3302 WSTOPSIG (w
), lwpid_of (current_thread
));
3304 /* Allow debugging the jump pad itself. */
3305 if (current_thread
->last_resume_kind
!= resume_step
3306 && maybe_move_out_of_jump_pad (event_child
, &w
))
3308 enqueue_one_deferred_signal (event_child
, &w
);
3311 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3312 WSTOPSIG (w
), lwpid_of (current_thread
));
3314 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
3316 return ignore_event (ourstatus
);
3320 if (event_child
->collecting_fast_tracepoint
)
3323 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3324 "Check if we're already there.\n",
3325 lwpid_of (current_thread
),
3326 event_child
->collecting_fast_tracepoint
);
3330 event_child
->collecting_fast_tracepoint
3331 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3333 if (event_child
->collecting_fast_tracepoint
!= 1)
3335 /* No longer need this breakpoint. */
3336 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3339 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3340 "stopping all threads momentarily.\n");
3342 /* Other running threads could hit this breakpoint.
3343 We don't handle moribund locations like GDB does,
3344 instead we always pause all threads when removing
3345 breakpoints, so that any step-over or
3346 decr_pc_after_break adjustment is always taken
3347 care of while the breakpoint is still
3349 stop_all_lwps (1, event_child
);
3351 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3352 event_child
->exit_jump_pad_bkpt
= NULL
;
3354 unstop_all_lwps (1, event_child
);
3356 gdb_assert (event_child
->suspended
>= 0);
3360 if (event_child
->collecting_fast_tracepoint
== 0)
3363 debug_printf ("fast tracepoint finished "
3364 "collecting successfully.\n");
3366 /* We may have a deferred signal to report. */
3367 if (dequeue_one_deferred_signal (event_child
, &w
))
3370 debug_printf ("dequeued one signal.\n");
3375 debug_printf ("no deferred signals.\n");
3377 if (stabilizing_threads
)
3379 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3380 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3384 debug_printf ("linux_wait_1 ret = %s, stopped "
3385 "while stabilizing threads\n",
3386 target_pid_to_str (ptid_of (current_thread
)));
3390 return ptid_of (current_thread
);
3396 /* Check whether GDB would be interested in this event. */
3398 /* Check if GDB is interested in this syscall. */
3400 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3401 && !gdb_catch_this_syscall_p (event_child
))
3405 debug_printf ("Ignored syscall for LWP %ld.\n",
3406 lwpid_of (current_thread
));
3409 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3411 return ignore_event (ourstatus
);
3414 /* If GDB is not interested in this signal, don't stop other
3415 threads, and don't report it to GDB. Just resume the inferior
3416 right away. We do this for threading-related signals as well as
3417 any that GDB specifically requested we ignore. But never ignore
3418 SIGSTOP if we sent it ourselves, and do not ignore signals when
3419 stepping - they may require special handling to skip the signal
3420 handler. Also never ignore signals that could be caused by a
3423 && current_thread
->last_resume_kind
!= resume_step
3425 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3426 (current_process ()->priv
->thread_db
!= NULL
3427 && (WSTOPSIG (w
) == __SIGRTMIN
3428 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3431 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3432 && !(WSTOPSIG (w
) == SIGSTOP
3433 && current_thread
->last_resume_kind
== resume_stop
)
3434 && !linux_wstatus_maybe_breakpoint (w
))))
3436 siginfo_t info
, *info_p
;
3439 debug_printf ("Ignored signal %d for LWP %ld.\n",
3440 WSTOPSIG (w
), lwpid_of (current_thread
));
3442 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3443 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3448 if (step_over_finished
)
3450 /* We cancelled this thread's step-over above. We still
3451 need to unsuspend all other LWPs, and set them back
3452 running again while the signal handler runs. */
3453 unsuspend_all_lwps (event_child
);
3455 /* Enqueue the pending signal info so that proceed_all_lwps
3457 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3459 proceed_all_lwps ();
3463 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3464 WSTOPSIG (w
), info_p
);
3466 return ignore_event (ourstatus
);
3469 /* Note that all addresses are always "out of the step range" when
3470 there's no range to begin with. */
3471 in_step_range
= lwp_in_step_range (event_child
);
3473 /* If GDB wanted this thread to single step, and the thread is out
3474 of the step range, we always want to report the SIGTRAP, and let
3475 GDB handle it. Watchpoints should always be reported. So should
3476 signals we can't explain. A SIGTRAP we can't explain could be a
3477 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3478 do, we're be able to handle GDB breakpoints on top of internal
3479 breakpoints, by handling the internal breakpoint and still
3480 reporting the event to GDB. If we don't, we're out of luck, GDB
3481 won't see the breakpoint hit. If we see a single-step event but
3482 the thread should be continuing, don't pass the trap to gdb.
3483 That indicates that we had previously finished a single-step but
3484 left the single-step pending -- see
3485 complete_ongoing_step_over. */
3486 report_to_gdb
= (!maybe_internal_trap
3487 || (current_thread
->last_resume_kind
== resume_step
3489 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3491 && !bp_explains_trap
3493 && !step_over_finished
3494 && !(current_thread
->last_resume_kind
== resume_continue
3495 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3496 || (gdb_breakpoint_here (event_child
->stop_pc
)
3497 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3498 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3499 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3501 run_breakpoint_commands (event_child
->stop_pc
);
3503 /* We found no reason GDB would want us to stop. We either hit one
3504 of our own breakpoints, or finished an internal step GDB
3505 shouldn't know about. */
3510 if (bp_explains_trap
)
3511 debug_printf ("Hit a gdbserver breakpoint.\n");
3512 if (step_over_finished
)
3513 debug_printf ("Step-over finished.\n");
3515 debug_printf ("Tracepoint event.\n");
3516 if (lwp_in_step_range (event_child
))
3517 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3518 paddress (event_child
->stop_pc
),
3519 paddress (event_child
->step_range_start
),
3520 paddress (event_child
->step_range_end
));
3523 /* We're not reporting this breakpoint to GDB, so apply the
3524 decr_pc_after_break adjustment to the inferior's regcache
3527 if (the_low_target
.set_pc
!= NULL
)
3529 struct regcache
*regcache
3530 = get_thread_regcache (current_thread
, 1);
3531 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3534 /* We may have finished stepping over a breakpoint. If so,
3535 we've stopped and suspended all LWPs momentarily except the
3536 stepping one. This is where we resume them all again. We're
3537 going to keep waiting, so use proceed, which handles stepping
3538 over the next breakpoint. */
3540 debug_printf ("proceeding all threads.\n");
3542 if (step_over_finished
)
3543 unsuspend_all_lwps (event_child
);
3545 proceed_all_lwps ();
3546 return ignore_event (ourstatus
);
3551 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3555 str
= target_waitstatus_to_string (&event_child
->waitstatus
);
3556 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3557 lwpid_of (get_lwp_thread (event_child
)), str
);
3560 if (current_thread
->last_resume_kind
== resume_step
)
3562 if (event_child
->step_range_start
== event_child
->step_range_end
)
3563 debug_printf ("GDB wanted to single-step, reporting event.\n");
3564 else if (!lwp_in_step_range (event_child
))
3565 debug_printf ("Out of step range, reporting event.\n");
3567 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3568 debug_printf ("Stopped by watchpoint.\n");
3569 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3570 debug_printf ("Stopped by GDB breakpoint.\n");
3572 debug_printf ("Hit a non-gdbserver trap event.\n");
3575 /* Alright, we're going to report a stop. */
3577 if (!stabilizing_threads
)
3579 /* In all-stop, stop all threads. */
3581 stop_all_lwps (0, NULL
);
3583 /* If we're not waiting for a specific LWP, choose an event LWP
3584 from among those that have had events. Giving equal priority
3585 to all LWPs that have had events helps prevent
3587 if (ptid_equal (ptid
, minus_one_ptid
))
3589 event_child
->status_pending_p
= 1;
3590 event_child
->status_pending
= w
;
3592 select_event_lwp (&event_child
);
3594 /* current_thread and event_child must stay in sync. */
3595 current_thread
= get_lwp_thread (event_child
);
3597 event_child
->status_pending_p
= 0;
3598 w
= event_child
->status_pending
;
3601 if (step_over_finished
)
3605 /* If we were doing a step-over, all other threads but
3606 the stepping one had been paused in start_step_over,
3607 with their suspend counts incremented. We don't want
3608 to do a full unstop/unpause, because we're in
3609 all-stop mode (so we want threads stopped), but we
3610 still need to unsuspend the other threads, to
3611 decrement their `suspended' count back. */
3612 unsuspend_all_lwps (event_child
);
3616 /* If we just finished a step-over, then all threads had
3617 been momentarily paused. In all-stop, that's fine,
3618 we want threads stopped by now anyway. In non-stop,
3619 we need to re-resume threads that GDB wanted to be
3621 unstop_all_lwps (1, event_child
);
3625 /* Stabilize threads (move out of jump pads). */
3627 stabilize_threads ();
3631 /* If we just finished a step-over, then all threads had been
3632 momentarily paused. In all-stop, that's fine, we want
3633 threads stopped by now anyway. In non-stop, we need to
3634 re-resume threads that GDB wanted to be running. */
3635 if (step_over_finished
)
3636 unstop_all_lwps (1, event_child
);
3639 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3641 /* If the reported event is an exit, fork, vfork or exec, let
3643 *ourstatus
= event_child
->waitstatus
;
3644 /* Clear the event lwp's waitstatus since we handled it already. */
3645 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3648 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3650 /* Now that we've selected our final event LWP, un-adjust its PC if
3651 it was a software breakpoint, and the client doesn't know we can
3652 adjust the breakpoint ourselves. */
3653 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3654 && !swbreak_feature
)
3656 int decr_pc
= the_low_target
.decr_pc_after_break
;
3660 struct regcache
*regcache
3661 = get_thread_regcache (current_thread
, 1);
3662 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3666 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3670 get_syscall_trapinfo (event_child
,
3671 &ourstatus
->value
.syscall_number
, &sysret
);
3672 ourstatus
->kind
= event_child
->syscall_state
;
3674 else if (current_thread
->last_resume_kind
== resume_stop
3675 && WSTOPSIG (w
) == SIGSTOP
)
3677 /* A thread that has been requested to stop by GDB with vCont;t,
3678 and it stopped cleanly, so report as SIG0. The use of
3679 SIGSTOP is an implementation detail. */
3680 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3682 else if (current_thread
->last_resume_kind
== resume_stop
3683 && WSTOPSIG (w
) != SIGSTOP
)
3685 /* A thread that has been requested to stop by GDB with vCont;t,
3686 but, it stopped for other reasons. */
3687 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3689 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3691 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3694 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
3698 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3699 target_pid_to_str (ptid_of (current_thread
)),
3700 ourstatus
->kind
, ourstatus
->value
.sig
);
3704 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3705 return filter_exit_event (event_child
, ourstatus
);
3707 return ptid_of (current_thread
);
3710 /* Get rid of any pending event in the pipe. */
3712 async_file_flush (void)
3718 ret
= read (linux_event_pipe
[0], &buf
, 1);
3719 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3722 /* Put something in the pipe, so the event loop wakes up. */
3724 async_file_mark (void)
3728 async_file_flush ();
3731 ret
= write (linux_event_pipe
[1], "+", 1);
3732 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3734 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3735 be awakened anyway. */
3739 linux_wait (ptid_t ptid
,
3740 struct target_waitstatus
*ourstatus
, int target_options
)
3744 /* Flush the async file first. */
3745 if (target_is_async_p ())
3746 async_file_flush ();
3750 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3752 while ((target_options
& TARGET_WNOHANG
) == 0
3753 && ptid_equal (event_ptid
, null_ptid
)
3754 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3756 /* If at least one stop was reported, there may be more. A single
3757 SIGCHLD can signal more than one child stop. */
3758 if (target_is_async_p ()
3759 && (target_options
& TARGET_WNOHANG
) != 0
3760 && !ptid_equal (event_ptid
, null_ptid
))
3766 /* Send a signal to an LWP. */
3769 kill_lwp (unsigned long lwpid
, int signo
)
3774 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3775 if (errno
== ENOSYS
)
3777 /* If tkill fails, then we are not using nptl threads, a
3778 configuration we no longer support. */
3779 perror_with_name (("tkill"));
3785 linux_stop_lwp (struct lwp_info
*lwp
)
3791 send_sigstop (struct lwp_info
*lwp
)
3795 pid
= lwpid_of (get_lwp_thread (lwp
));
3797 /* If we already have a pending stop signal for this process, don't
3799 if (lwp
->stop_expected
)
3802 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3808 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3810 lwp
->stop_expected
= 1;
3811 kill_lwp (pid
, SIGSTOP
);
3815 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
3817 struct thread_info
*thread
= (struct thread_info
*) entry
;
3818 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3820 /* Ignore EXCEPT. */
3831 /* Increment the suspend count of an LWP, and stop it, if not stopped
3834 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
3837 struct thread_info
*thread
= (struct thread_info
*) entry
;
3838 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3840 /* Ignore EXCEPT. */
3844 lwp_suspended_inc (lwp
);
3846 return send_sigstop_callback (entry
, except
);
3850 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3852 /* Store the exit status for later. */
3853 lwp
->status_pending_p
= 1;
3854 lwp
->status_pending
= wstat
;
3856 /* Store in waitstatus as well, as there's nothing else to process
3858 if (WIFEXITED (wstat
))
3860 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3861 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3863 else if (WIFSIGNALED (wstat
))
3865 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3866 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3869 /* Prevent trying to stop it. */
3872 /* No further stops are expected from a dead lwp. */
3873 lwp
->stop_expected
= 0;
3876 /* Return true if LWP has exited already, and has a pending exit event
3877 to report to GDB. */
3880 lwp_is_marked_dead (struct lwp_info
*lwp
)
3882 return (lwp
->status_pending_p
3883 && (WIFEXITED (lwp
->status_pending
)
3884 || WIFSIGNALED (lwp
->status_pending
)));
3887 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3890 wait_for_sigstop (void)
3892 struct thread_info
*saved_thread
;
3897 saved_thread
= current_thread
;
3898 if (saved_thread
!= NULL
)
3899 saved_tid
= saved_thread
->entry
.id
;
3901 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3904 debug_printf ("wait_for_sigstop: pulling events\n");
3906 /* Passing NULL_PTID as filter indicates we want all events to be
3907 left pending. Eventually this returns when there are no
3908 unwaited-for children left. */
3909 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
3911 gdb_assert (ret
== -1);
3913 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
3914 current_thread
= saved_thread
;
3918 debug_printf ("Previously current thread died.\n");
3920 /* We can't change the current inferior behind GDB's back,
3921 otherwise, a subsequent command may apply to the wrong
3923 current_thread
= NULL
;
3927 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3928 move it out, because we need to report the stop event to GDB. For
3929 example, if the user puts a breakpoint in the jump pad, it's
3930 because she wants to debug it. */
3933 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3935 struct thread_info
*thread
= (struct thread_info
*) entry
;
3936 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3938 if (lwp
->suspended
!= 0)
3940 internal_error (__FILE__
, __LINE__
,
3941 "LWP %ld is suspended, suspended=%d\n",
3942 lwpid_of (thread
), lwp
->suspended
);
3944 gdb_assert (lwp
->stopped
);
3946 /* Allow debugging the jump pad, gdb_collect, etc.. */
3947 return (supports_fast_tracepoints ()
3948 && agent_loaded_p ()
3949 && (gdb_breakpoint_here (lwp
->stop_pc
)
3950 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3951 || thread
->last_resume_kind
== resume_step
)
3952 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3956 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3958 struct thread_info
*thread
= (struct thread_info
*) entry
;
3959 struct thread_info
*saved_thread
;
3960 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3963 if (lwp
->suspended
!= 0)
3965 internal_error (__FILE__
, __LINE__
,
3966 "LWP %ld is suspended, suspended=%d\n",
3967 lwpid_of (thread
), lwp
->suspended
);
3969 gdb_assert (lwp
->stopped
);
3971 /* For gdb_breakpoint_here. */
3972 saved_thread
= current_thread
;
3973 current_thread
= thread
;
3975 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3977 /* Allow debugging the jump pad, gdb_collect, etc. */
3978 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3979 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3980 && thread
->last_resume_kind
!= resume_step
3981 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3984 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3989 lwp
->status_pending_p
= 0;
3990 enqueue_one_deferred_signal (lwp
, wstat
);
3993 debug_printf ("Signal %d for LWP %ld deferred "
3995 WSTOPSIG (*wstat
), lwpid_of (thread
));
3998 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
4001 lwp_suspended_inc (lwp
);
4003 current_thread
= saved_thread
;
4007 lwp_running (struct inferior_list_entry
*entry
, void *data
)
4009 struct thread_info
*thread
= (struct thread_info
*) entry
;
4010 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4012 if (lwp_is_marked_dead (lwp
))
4019 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
4020 If SUSPEND, then also increase the suspend count of every LWP,
4024 stop_all_lwps (int suspend
, struct lwp_info
*except
)
4026 /* Should not be called recursively. */
4027 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
4032 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4033 suspend
? "stop-and-suspend" : "stop",
4035 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
4039 stopping_threads
= (suspend
4040 ? STOPPING_AND_SUSPENDING_THREADS
4041 : STOPPING_THREADS
);
4044 find_inferior (&all_threads
, suspend_and_send_sigstop_callback
, except
);
4046 find_inferior (&all_threads
, send_sigstop_callback
, except
);
4047 wait_for_sigstop ();
4048 stopping_threads
= NOT_STOPPING_THREADS
;
4052 debug_printf ("stop_all_lwps done, setting stopping_threads "
4053 "back to !stopping\n");
4058 /* Enqueue one signal in the chain of signals which need to be
4059 delivered to this process on next resume. */
4062 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
4064 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
4066 p_sig
->prev
= lwp
->pending_signals
;
4067 p_sig
->signal
= signal
;
4069 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4071 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
4072 lwp
->pending_signals
= p_sig
;
4075 /* Install breakpoints for software single stepping. */
4078 install_software_single_step_breakpoints (struct lwp_info
*lwp
)
4082 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4083 VEC (CORE_ADDR
) *next_pcs
= NULL
;
4084 struct cleanup
*old_chain
= make_cleanup (VEC_cleanup (CORE_ADDR
), &next_pcs
);
4086 next_pcs
= (*the_low_target
.get_next_pcs
) (regcache
);
4088 for (i
= 0; VEC_iterate (CORE_ADDR
, next_pcs
, i
, pc
); ++i
)
4089 set_reinsert_breakpoint (pc
);
4091 do_cleanups (old_chain
);
4094 /* Single step via hardware or software single step.
4095 Return 1 if hardware single stepping, 0 if software single stepping
4096 or can't single step. */
4099 single_step (struct lwp_info
* lwp
)
4103 if (can_hardware_single_step ())
4107 else if (can_software_single_step ())
4109 install_software_single_step_breakpoints (lwp
);
4115 debug_printf ("stepping is not implemented on this target");
4121 /* The signal can be delivered to the inferior if we are not trying to
4122 reinsert a breakpoint and not trying to finish a fast tracepoint
4126 lwp_signal_can_be_delivered (struct lwp_info
*lwp
)
4128 return (lwp
->bp_reinsert
== 0 && !lwp
->collecting_fast_tracepoint
);
4131 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
4132 SIGNAL is nonzero, give it that signal. */
4135 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
4136 int step
, int signal
, siginfo_t
*info
)
4138 struct thread_info
*thread
= get_lwp_thread (lwp
);
4139 struct thread_info
*saved_thread
;
4140 int fast_tp_collecting
;
4142 struct process_info
*proc
= get_thread_process (thread
);
4144 /* Note that target description may not be initialised
4145 (proc->tdesc == NULL) at this point because the program hasn't
4146 stopped at the first instruction yet. It means GDBserver skips
4147 the extra traps from the wrapper program (see option --wrapper).
4148 Code in this function that requires register access should be
4149 guarded by proc->tdesc == NULL or something else. */
4151 if (lwp
->stopped
== 0)
4154 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
4156 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
4158 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
4160 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4161 user used the "jump" command, or "set $pc = foo"). */
4162 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
4164 /* Collecting 'while-stepping' actions doesn't make sense
4166 release_while_stepping_state_list (thread
);
4169 /* If we have pending signals or status, and a new signal, enqueue the
4170 signal. Also enqueue the signal if it can't be delivered to the
4171 inferior right now. */
4173 && (lwp
->status_pending_p
4174 || lwp
->pending_signals
!= NULL
4175 || !lwp_signal_can_be_delivered (lwp
)))
4177 enqueue_pending_signal (lwp
, signal
, info
);
4179 /* Postpone any pending signal. It was enqueued above. */
4183 if (lwp
->status_pending_p
)
4186 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4187 " has pending status\n",
4188 lwpid_of (thread
), step
? "step" : "continue",
4189 lwp
->stop_expected
? "expected" : "not expected");
4193 saved_thread
= current_thread
;
4194 current_thread
= thread
;
4196 /* This bit needs some thinking about. If we get a signal that
4197 we must report while a single-step reinsert is still pending,
4198 we often end up resuming the thread. It might be better to
4199 (ew) allow a stack of pending events; then we could be sure that
4200 the reinsert happened right away and not lose any signals.
4202 Making this stack would also shrink the window in which breakpoints are
4203 uninserted (see comment in linux_wait_for_lwp) but not enough for
4204 complete correctness, so it won't solve that problem. It may be
4205 worthwhile just to solve this one, however. */
4206 if (lwp
->bp_reinsert
!= 0)
4209 debug_printf (" pending reinsert at 0x%s\n",
4210 paddress (lwp
->bp_reinsert
));
4212 if (can_hardware_single_step ())
4214 if (fast_tp_collecting
== 0)
4217 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
4219 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
4227 if (fast_tp_collecting
== 1)
4230 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4231 " (exit-jump-pad-bkpt)\n",
4234 else if (fast_tp_collecting
== 2)
4237 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4238 " single-stepping\n",
4241 if (can_hardware_single_step ())
4245 internal_error (__FILE__
, __LINE__
,
4246 "moving out of jump pad single-stepping"
4247 " not implemented on this target");
4251 /* If we have while-stepping actions in this thread set it stepping.
4252 If we have a signal to deliver, it may or may not be set to
4253 SIG_IGN, we don't know. Assume so, and allow collecting
4254 while-stepping into a signal handler. A possible smart thing to
4255 do would be to set an internal breakpoint at the signal return
4256 address, continue, and carry on catching this while-stepping
4257 action only when that breakpoint is hit. A future
4259 if (thread
->while_stepping
!= NULL
)
4262 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4265 step
= single_step (lwp
);
4268 if (proc
->tdesc
!= NULL
&& the_low_target
.get_pc
!= NULL
)
4270 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4272 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
4276 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4277 (long) lwp
->stop_pc
);
4281 /* If we have pending signals, consume one if it can be delivered to
4283 if (lwp
->pending_signals
!= NULL
&& lwp_signal_can_be_delivered (lwp
))
4285 struct pending_signals
**p_sig
;
4287 p_sig
= &lwp
->pending_signals
;
4288 while ((*p_sig
)->prev
!= NULL
)
4289 p_sig
= &(*p_sig
)->prev
;
4291 signal
= (*p_sig
)->signal
;
4292 if ((*p_sig
)->info
.si_signo
!= 0)
4293 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4301 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4302 lwpid_of (thread
), step
? "step" : "continue", signal
,
4303 lwp
->stop_expected
? "expected" : "not expected");
4305 if (the_low_target
.prepare_to_resume
!= NULL
)
4306 the_low_target
.prepare_to_resume (lwp
);
4308 regcache_invalidate_thread (thread
);
4310 lwp
->stepping
= step
;
4312 ptrace_request
= PTRACE_SINGLESTEP
;
4313 else if (gdb_catching_syscalls_p (lwp
))
4314 ptrace_request
= PTRACE_SYSCALL
;
4316 ptrace_request
= PTRACE_CONT
;
4317 ptrace (ptrace_request
,
4319 (PTRACE_TYPE_ARG3
) 0,
4320 /* Coerce to a uintptr_t first to avoid potential gcc warning
4321 of coercing an 8 byte integer to a 4 byte pointer. */
4322 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4324 current_thread
= saved_thread
;
4326 perror_with_name ("resuming thread");
4328 /* Successfully resumed. Clear state that no longer makes sense,
4329 and mark the LWP as running. Must not do this before resuming
4330 otherwise if that fails other code will be confused. E.g., we'd
4331 later try to stop the LWP and hang forever waiting for a stop
4332 status. Note that we must not throw after this is cleared,
4333 otherwise handle_zombie_lwp_error would get confused. */
4335 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4338 /* Called when we try to resume a stopped LWP and that errors out. If
4339 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4340 or about to become), discard the error, clear any pending status
4341 the LWP may have, and return true (we'll collect the exit status
4342 soon enough). Otherwise, return false. */
4345 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4347 struct thread_info
*thread
= get_lwp_thread (lp
);
4349 /* If we get an error after resuming the LWP successfully, we'd
4350 confuse !T state for the LWP being gone. */
4351 gdb_assert (lp
->stopped
);
4353 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4354 because even if ptrace failed with ESRCH, the tracee may be "not
4355 yet fully dead", but already refusing ptrace requests. In that
4356 case the tracee has 'R (Running)' state for a little bit
4357 (observed in Linux 3.18). See also the note on ESRCH in the
4358 ptrace(2) man page. Instead, check whether the LWP has any state
4359 other than ptrace-stopped. */
4361 /* Don't assume anything if /proc/PID/status can't be read. */
4362 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4364 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4365 lp
->status_pending_p
= 0;
4371 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4372 disappears while we try to resume it. */
4375 linux_resume_one_lwp (struct lwp_info
*lwp
,
4376 int step
, int signal
, siginfo_t
*info
)
4380 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
4382 CATCH (ex
, RETURN_MASK_ERROR
)
4384 if (!check_ptrace_stopped_lwp_gone (lwp
))
4385 throw_exception (ex
);
4390 struct thread_resume_array
4392 struct thread_resume
*resume
;
4396 /* This function is called once per thread via find_inferior.
4397 ARG is a pointer to a thread_resume_array struct.
4398 We look up the thread specified by ENTRY in ARG, and mark the thread
4399 with a pointer to the appropriate resume request.
4401 This algorithm is O(threads * resume elements), but resume elements
4402 is small (and will remain small at least until GDB supports thread
4406 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
4408 struct thread_info
*thread
= (struct thread_info
*) entry
;
4409 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4411 struct thread_resume_array
*r
;
4413 r
= (struct thread_resume_array
*) arg
;
4415 for (ndx
= 0; ndx
< r
->n
; ndx
++)
4417 ptid_t ptid
= r
->resume
[ndx
].thread
;
4418 if (ptid_equal (ptid
, minus_one_ptid
)
4419 || ptid_equal (ptid
, entry
->id
)
4420 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4422 || (ptid_get_pid (ptid
) == pid_of (thread
)
4423 && (ptid_is_pid (ptid
)
4424 || ptid_get_lwp (ptid
) == -1)))
4426 if (r
->resume
[ndx
].kind
== resume_stop
4427 && thread
->last_resume_kind
== resume_stop
)
4430 debug_printf ("already %s LWP %ld at GDB's request\n",
4431 (thread
->last_status
.kind
4432 == TARGET_WAITKIND_STOPPED
)
4440 lwp
->resume
= &r
->resume
[ndx
];
4441 thread
->last_resume_kind
= lwp
->resume
->kind
;
4443 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4444 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4446 /* If we had a deferred signal to report, dequeue one now.
4447 This can happen if LWP gets more than one signal while
4448 trying to get out of a jump pad. */
4450 && !lwp
->status_pending_p
4451 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4453 lwp
->status_pending_p
= 1;
4456 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4457 "leaving status pending.\n",
4458 WSTOPSIG (lwp
->status_pending
),
4466 /* No resume action for this thread. */
4472 /* find_inferior callback for linux_resume.
4473 Set *FLAG_P if this lwp has an interesting status pending. */
4476 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
4478 struct thread_info
*thread
= (struct thread_info
*) entry
;
4479 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4481 /* LWPs which will not be resumed are not interesting, because
4482 we might not wait for them next time through linux_wait. */
4483 if (lwp
->resume
== NULL
)
4486 if (thread_still_has_status_pending_p (thread
))
4487 * (int *) flag_p
= 1;
4492 /* Return 1 if this lwp that GDB wants running is stopped at an
4493 internal breakpoint that we need to step over. It assumes that any
4494 required STOP_PC adjustment has already been propagated to the
4495 inferior's regcache. */
4498 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
4500 struct thread_info
*thread
= (struct thread_info
*) entry
;
4501 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4502 struct thread_info
*saved_thread
;
4504 struct process_info
*proc
= get_thread_process (thread
);
4506 /* GDBserver is skipping the extra traps from the wrapper program,
4507 don't have to do step over. */
4508 if (proc
->tdesc
== NULL
)
4511 /* LWPs which will not be resumed are not interesting, because we
4512 might not wait for them next time through linux_wait. */
4517 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4522 if (thread
->last_resume_kind
== resume_stop
)
4525 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4531 gdb_assert (lwp
->suspended
>= 0);
4536 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4541 if (!lwp
->need_step_over
)
4544 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (thread
));
4547 if (lwp
->status_pending_p
)
4550 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4556 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4560 /* If the PC has changed since we stopped, then don't do anything,
4561 and let the breakpoint/tracepoint be hit. This happens if, for
4562 instance, GDB handled the decr_pc_after_break subtraction itself,
4563 GDB is OOL stepping this thread, or the user has issued a "jump"
4564 command, or poked thread's registers herself. */
4565 if (pc
!= lwp
->stop_pc
)
4568 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4569 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4571 paddress (lwp
->stop_pc
), paddress (pc
));
4573 lwp
->need_step_over
= 0;
4577 saved_thread
= current_thread
;
4578 current_thread
= thread
;
4580 /* We can only step over breakpoints we know about. */
4581 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4583 /* Don't step over a breakpoint that GDB expects to hit
4584 though. If the condition is being evaluated on the target's side
4585 and it evaluate to false, step over this breakpoint as well. */
4586 if (gdb_breakpoint_here (pc
)
4587 && gdb_condition_true_at_breakpoint (pc
)
4588 && gdb_no_commands_at_breakpoint (pc
))
4591 debug_printf ("Need step over [LWP %ld]? yes, but found"
4592 " GDB breakpoint at 0x%s; skipping step over\n",
4593 lwpid_of (thread
), paddress (pc
));
4595 current_thread
= saved_thread
;
4601 debug_printf ("Need step over [LWP %ld]? yes, "
4602 "found breakpoint at 0x%s\n",
4603 lwpid_of (thread
), paddress (pc
));
4605 /* We've found an lwp that needs stepping over --- return 1 so
4606 that find_inferior stops looking. */
4607 current_thread
= saved_thread
;
4609 /* If the step over is cancelled, this is set again. */
4610 lwp
->need_step_over
= 0;
4615 current_thread
= saved_thread
;
4618 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4620 lwpid_of (thread
), paddress (pc
));
4625 /* Start a step-over operation on LWP. When LWP stopped at a
4626 breakpoint, to make progress, we need to remove the breakpoint out
4627 of the way. If we let other threads run while we do that, they may
4628 pass by the breakpoint location and miss hitting it. To avoid
4629 that, a step-over momentarily stops all threads while LWP is
4630 single-stepped by either hardware or software while the breakpoint
4631 is temporarily uninserted from the inferior. When the single-step
4632 finishes, we reinsert the breakpoint, and let all threads that are
4633 supposed to be running, run again. */
4636 start_step_over (struct lwp_info
*lwp
)
4638 struct thread_info
*thread
= get_lwp_thread (lwp
);
4639 struct thread_info
*saved_thread
;
4644 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4647 stop_all_lwps (1, lwp
);
4649 if (lwp
->suspended
!= 0)
4651 internal_error (__FILE__
, __LINE__
,
4652 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4657 debug_printf ("Done stopping all threads for step-over.\n");
4659 /* Note, we should always reach here with an already adjusted PC,
4660 either by GDB (if we're resuming due to GDB's request), or by our
4661 caller, if we just finished handling an internal breakpoint GDB
4662 shouldn't care about. */
4665 saved_thread
= current_thread
;
4666 current_thread
= thread
;
4668 lwp
->bp_reinsert
= pc
;
4669 uninsert_breakpoints_at (pc
);
4670 uninsert_fast_tracepoint_jumps_at (pc
);
4672 step
= single_step (lwp
);
4674 current_thread
= saved_thread
;
4676 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4678 /* Require next event from this LWP. */
4679 step_over_bkpt
= thread
->entry
.id
;
4683 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4684 start_step_over, if still there, and delete any reinsert
4685 breakpoints we've set, on non hardware single-step targets. */
4688 finish_step_over (struct lwp_info
*lwp
)
4690 if (lwp
->bp_reinsert
!= 0)
4693 debug_printf ("Finished step over.\n");
4695 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4696 may be no breakpoint to reinsert there by now. */
4697 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4698 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4700 lwp
->bp_reinsert
= 0;
4702 /* Delete any software-single-step reinsert breakpoints. No
4703 longer needed. We don't have to worry about other threads
4704 hitting this trap, and later not being able to explain it,
4705 because we were stepping over a breakpoint, and we hold all
4706 threads but LWP stopped while doing that. */
4707 if (!can_hardware_single_step ())
4708 delete_reinsert_breakpoints ();
4710 step_over_bkpt
= null_ptid
;
4717 /* If there's a step over in progress, wait until all threads stop
4718 (that is, until the stepping thread finishes its step), and
4719 unsuspend all lwps. The stepping thread ends with its status
4720 pending, which is processed later when we get back to processing
4724 complete_ongoing_step_over (void)
4726 if (!ptid_equal (step_over_bkpt
, null_ptid
))
4728 struct lwp_info
*lwp
;
4733 debug_printf ("detach: step over in progress, finish it first\n");
4735 /* Passing NULL_PTID as filter indicates we want all events to
4736 be left pending. Eventually this returns when there are no
4737 unwaited-for children left. */
4738 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4740 gdb_assert (ret
== -1);
4742 lwp
= find_lwp_pid (step_over_bkpt
);
4744 finish_step_over (lwp
);
4745 step_over_bkpt
= null_ptid
;
4746 unsuspend_all_lwps (lwp
);
4750 /* This function is called once per thread. We check the thread's resume
4751 request, which will tell us whether to resume, step, or leave the thread
4752 stopped; and what signal, if any, it should be sent.
4754 For threads which we aren't explicitly told otherwise, we preserve
4755 the stepping flag; this is used for stepping over gdbserver-placed
4758 If pending_flags was set in any thread, we queue any needed
4759 signals, since we won't actually resume. We already have a pending
4760 event to report, so we don't need to preserve any step requests;
4761 they should be re-issued if necessary. */
4764 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
4766 struct thread_info
*thread
= (struct thread_info
*) entry
;
4767 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4769 int leave_all_stopped
= * (int *) arg
;
4772 if (lwp
->resume
== NULL
)
4775 if (lwp
->resume
->kind
== resume_stop
)
4778 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4783 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4785 /* Stop the thread, and wait for the event asynchronously,
4786 through the event loop. */
4792 debug_printf ("already stopped LWP %ld\n",
4795 /* The LWP may have been stopped in an internal event that
4796 was not meant to be notified back to GDB (e.g., gdbserver
4797 breakpoint), so we should be reporting a stop event in
4800 /* If the thread already has a pending SIGSTOP, this is a
4801 no-op. Otherwise, something later will presumably resume
4802 the thread and this will cause it to cancel any pending
4803 operation, due to last_resume_kind == resume_stop. If
4804 the thread already has a pending status to report, we
4805 will still report it the next time we wait - see
4806 status_pending_p_callback. */
4808 /* If we already have a pending signal to report, then
4809 there's no need to queue a SIGSTOP, as this means we're
4810 midway through moving the LWP out of the jumppad, and we
4811 will report the pending signal as soon as that is
4813 if (lwp
->pending_signals_to_report
== NULL
)
4817 /* For stop requests, we're done. */
4819 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4823 /* If this thread which is about to be resumed has a pending status,
4824 then don't resume it - we can just report the pending status.
4825 Likewise if it is suspended, because e.g., another thread is
4826 stepping past a breakpoint. Make sure to queue any signals that
4827 would otherwise be sent. In all-stop mode, we do this decision
4828 based on if *any* thread has a pending status. If there's a
4829 thread that needs the step-over-breakpoint dance, then don't
4830 resume any other thread but that particular one. */
4831 leave_pending
= (lwp
->suspended
4832 || lwp
->status_pending_p
4833 || leave_all_stopped
);
4838 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4840 step
= (lwp
->resume
->kind
== resume_step
);
4841 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
4846 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4848 /* If we have a new signal, enqueue the signal. */
4849 if (lwp
->resume
->sig
!= 0)
4851 struct pending_signals
*p_sig
= XCNEW (struct pending_signals
);
4853 p_sig
->prev
= lwp
->pending_signals
;
4854 p_sig
->signal
= lwp
->resume
->sig
;
4856 /* If this is the same signal we were previously stopped by,
4857 make sure to queue its siginfo. We can ignore the return
4858 value of ptrace; if it fails, we'll skip
4859 PTRACE_SETSIGINFO. */
4860 if (WIFSTOPPED (lwp
->last_status
)
4861 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
4862 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4865 lwp
->pending_signals
= p_sig
;
4869 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4875 linux_resume (struct thread_resume
*resume_info
, size_t n
)
4877 struct thread_resume_array array
= { resume_info
, n
};
4878 struct thread_info
*need_step_over
= NULL
;
4880 int leave_all_stopped
;
4885 debug_printf ("linux_resume:\n");
4888 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
4890 /* If there is a thread which would otherwise be resumed, which has
4891 a pending status, then don't resume any threads - we can just
4892 report the pending status. Make sure to queue any signals that
4893 would otherwise be sent. In non-stop mode, we'll apply this
4894 logic to each thread individually. We consume all pending events
4895 before considering to start a step-over (in all-stop). */
4898 find_inferior (&all_threads
, resume_status_pending_p
, &any_pending
);
4900 /* If there is a thread which would otherwise be resumed, which is
4901 stopped at a breakpoint that needs stepping over, then don't
4902 resume any threads - have it step over the breakpoint with all
4903 other threads stopped, then resume all threads again. Make sure
4904 to queue any signals that would otherwise be delivered or
4906 if (!any_pending
&& supports_breakpoints ())
4908 = (struct thread_info
*) find_inferior (&all_threads
,
4909 need_step_over_p
, NULL
);
4911 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4915 if (need_step_over
!= NULL
)
4916 debug_printf ("Not resuming all, need step over\n");
4917 else if (any_pending
)
4918 debug_printf ("Not resuming, all-stop and found "
4919 "an LWP with pending status\n");
4921 debug_printf ("Resuming, no pending status or step over needed\n");
4924 /* Even if we're leaving threads stopped, queue all signals we'd
4925 otherwise deliver. */
4926 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
4929 start_step_over (get_thread_lwp (need_step_over
));
4933 debug_printf ("linux_resume done\n");
4937 /* We may have events that were pending that can/should be sent to
4938 the client now. Trigger a linux_wait call. */
4939 if (target_is_async_p ())
4943 /* This function is called once per thread. We check the thread's
4944 last resume request, which will tell us whether to resume, step, or
4945 leave the thread stopped. Any signal the client requested to be
4946 delivered has already been enqueued at this point.
4948 If any thread that GDB wants running is stopped at an internal
4949 breakpoint that needs stepping over, we start a step-over operation
4950 on that particular thread, and leave all others stopped. */
4953 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4955 struct thread_info
*thread
= (struct thread_info
*) entry
;
4956 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4963 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
4968 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
4972 if (thread
->last_resume_kind
== resume_stop
4973 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
4976 debug_printf (" client wants LWP to remain %ld stopped\n",
4981 if (lwp
->status_pending_p
)
4984 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4989 gdb_assert (lwp
->suspended
>= 0);
4994 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
4998 if (thread
->last_resume_kind
== resume_stop
4999 && lwp
->pending_signals_to_report
== NULL
5000 && lwp
->collecting_fast_tracepoint
== 0)
5002 /* We haven't reported this LWP as stopped yet (otherwise, the
5003 last_status.kind check above would catch it, and we wouldn't
5004 reach here. This LWP may have been momentarily paused by a
5005 stop_all_lwps call while handling for example, another LWP's
5006 step-over. In that case, the pending expected SIGSTOP signal
5007 that was queued at vCont;t handling time will have already
5008 been consumed by wait_for_sigstop, and so we need to requeue
5009 another one here. Note that if the LWP already has a SIGSTOP
5010 pending, this is a no-op. */
5013 debug_printf ("Client wants LWP %ld to stop. "
5014 "Making sure it has a SIGSTOP pending\n",
5020 if (thread
->last_resume_kind
== resume_step
)
5023 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5027 else if (lwp
->bp_reinsert
!= 0)
5030 debug_printf (" stepping LWP %ld, reinsert set\n",
5037 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
5042 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
5044 struct thread_info
*thread
= (struct thread_info
*) entry
;
5045 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5050 lwp_suspended_decr (lwp
);
5052 return proceed_one_lwp (entry
, except
);
5055 /* When we finish a step-over, set threads running again. If there's
5056 another thread that may need a step-over, now's the time to start
5057 it. Eventually, we'll move all threads past their breakpoints. */
5060 proceed_all_lwps (void)
5062 struct thread_info
*need_step_over
;
5064 /* If there is a thread which would otherwise be resumed, which is
5065 stopped at a breakpoint that needs stepping over, then don't
5066 resume any threads - have it step over the breakpoint with all
5067 other threads stopped, then resume all threads again. */
5069 if (supports_breakpoints ())
5072 = (struct thread_info
*) find_inferior (&all_threads
,
5073 need_step_over_p
, NULL
);
5075 if (need_step_over
!= NULL
)
5078 debug_printf ("proceed_all_lwps: found "
5079 "thread %ld needing a step-over\n",
5080 lwpid_of (need_step_over
));
5082 start_step_over (get_thread_lwp (need_step_over
));
5088 debug_printf ("Proceeding, no step-over needed\n");
5090 find_inferior (&all_threads
, proceed_one_lwp
, NULL
);
5093 /* Stopped LWPs that the client wanted to be running, that don't have
5094 pending statuses, are set to run again, except for EXCEPT, if not
5095 NULL. This undoes a stop_all_lwps call. */
5098 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
5104 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5105 lwpid_of (get_lwp_thread (except
)));
5107 debug_printf ("unstopping all lwps\n");
5111 find_inferior (&all_threads
, unsuspend_and_proceed_one_lwp
, except
);
5113 find_inferior (&all_threads
, proceed_one_lwp
, except
);
5117 debug_printf ("unstop_all_lwps done\n");
5123 #ifdef HAVE_LINUX_REGSETS
5125 #define use_linux_regsets 1
5127 /* Returns true if REGSET has been disabled. */
5130 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
5132 return (info
->disabled_regsets
!= NULL
5133 && info
->disabled_regsets
[regset
- info
->regsets
]);
5136 /* Disable REGSET. */
5139 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5143 dr_offset
= regset
- info
->regsets
;
5144 if (info
->disabled_regsets
== NULL
)
5145 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5146 info
->disabled_regsets
[dr_offset
] = 1;
5150 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5151 struct regcache
*regcache
)
5153 struct regset_info
*regset
;
5154 int saw_general_regs
= 0;
5158 pid
= lwpid_of (current_thread
);
5159 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5164 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5167 buf
= xmalloc (regset
->size
);
5169 nt_type
= regset
->nt_type
;
5173 iov
.iov_len
= regset
->size
;
5174 data
= (void *) &iov
;
5180 res
= ptrace (regset
->get_request
, pid
,
5181 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5183 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5189 /* If we get EIO on a regset, do not try it again for
5190 this process mode. */
5191 disable_regset (regsets_info
, regset
);
5193 else if (errno
== ENODATA
)
5195 /* ENODATA may be returned if the regset is currently
5196 not "active". This can happen in normal operation,
5197 so suppress the warning in this case. */
5202 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5209 if (regset
->type
== GENERAL_REGS
)
5210 saw_general_regs
= 1;
5211 regset
->store_function (regcache
, buf
);
5215 if (saw_general_regs
)
5222 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5223 struct regcache
*regcache
)
5225 struct regset_info
*regset
;
5226 int saw_general_regs
= 0;
5230 pid
= lwpid_of (current_thread
);
5231 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5236 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5237 || regset
->fill_function
== NULL
)
5240 buf
= xmalloc (regset
->size
);
5242 /* First fill the buffer with the current register set contents,
5243 in case there are any items in the kernel's regset that are
5244 not in gdbserver's regcache. */
5246 nt_type
= regset
->nt_type
;
5250 iov
.iov_len
= regset
->size
;
5251 data
= (void *) &iov
;
5257 res
= ptrace (regset
->get_request
, pid
,
5258 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5260 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5265 /* Then overlay our cached registers on that. */
5266 regset
->fill_function (regcache
, buf
);
5268 /* Only now do we write the register set. */
5270 res
= ptrace (regset
->set_request
, pid
,
5271 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5273 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5281 /* If we get EIO on a regset, do not try it again for
5282 this process mode. */
5283 disable_regset (regsets_info
, regset
);
5285 else if (errno
== ESRCH
)
5287 /* At this point, ESRCH should mean the process is
5288 already gone, in which case we simply ignore attempts
5289 to change its registers. See also the related
5290 comment in linux_resume_one_lwp. */
5296 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5299 else if (regset
->type
== GENERAL_REGS
)
5300 saw_general_regs
= 1;
5303 if (saw_general_regs
)
5309 #else /* !HAVE_LINUX_REGSETS */
5311 #define use_linux_regsets 0
5312 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5313 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5317 /* Return 1 if register REGNO is supported by one of the regset ptrace
5318 calls or 0 if it has to be transferred individually. */
5321 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5323 unsigned char mask
= 1 << (regno
% 8);
5324 size_t index
= regno
/ 8;
5326 return (use_linux_regsets
5327 && (regs_info
->regset_bitmap
== NULL
5328 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5331 #ifdef HAVE_LINUX_USRREGS
5334 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5338 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5339 error ("Invalid register number %d.", regnum
);
5341 addr
= usrregs
->regmap
[regnum
];
5346 /* Fetch one register. */
5348 fetch_register (const struct usrregs_info
*usrregs
,
5349 struct regcache
*regcache
, int regno
)
5356 if (regno
>= usrregs
->num_regs
)
5358 if ((*the_low_target
.cannot_fetch_register
) (regno
))
5361 regaddr
= register_addr (usrregs
, regno
);
5365 size
= ((register_size (regcache
->tdesc
, regno
)
5366 + sizeof (PTRACE_XFER_TYPE
) - 1)
5367 & -sizeof (PTRACE_XFER_TYPE
));
5368 buf
= (char *) alloca (size
);
5370 pid
= lwpid_of (current_thread
);
5371 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5374 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5375 ptrace (PTRACE_PEEKUSER
, pid
,
5376 /* Coerce to a uintptr_t first to avoid potential gcc warning
5377 of coercing an 8 byte integer to a 4 byte pointer. */
5378 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5379 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5381 error ("reading register %d: %s", regno
, strerror (errno
));
5384 if (the_low_target
.supply_ptrace_register
)
5385 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
5387 supply_register (regcache
, regno
, buf
);
5390 /* Store one register. */
5392 store_register (const struct usrregs_info
*usrregs
,
5393 struct regcache
*regcache
, int regno
)
5400 if (regno
>= usrregs
->num_regs
)
5402 if ((*the_low_target
.cannot_store_register
) (regno
))
5405 regaddr
= register_addr (usrregs
, regno
);
5409 size
= ((register_size (regcache
->tdesc
, regno
)
5410 + sizeof (PTRACE_XFER_TYPE
) - 1)
5411 & -sizeof (PTRACE_XFER_TYPE
));
5412 buf
= (char *) alloca (size
);
5413 memset (buf
, 0, size
);
5415 if (the_low_target
.collect_ptrace_register
)
5416 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
5418 collect_register (regcache
, regno
, buf
);
5420 pid
= lwpid_of (current_thread
);
5421 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5424 ptrace (PTRACE_POKEUSER
, pid
,
5425 /* Coerce to a uintptr_t first to avoid potential gcc warning
5426 about coercing an 8 byte integer to a 4 byte pointer. */
5427 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5428 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5431 /* At this point, ESRCH should mean the process is
5432 already gone, in which case we simply ignore attempts
5433 to change its registers. See also the related
5434 comment in linux_resume_one_lwp. */
5438 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
5439 error ("writing register %d: %s", regno
, strerror (errno
));
5441 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5445 /* Fetch all registers, or just one, from the child process.
5446 If REGNO is -1, do this for all registers, skipping any that are
5447 assumed to have been retrieved by regsets_fetch_inferior_registers,
5448 unless ALL is non-zero.
5449 Otherwise, REGNO specifies which register (so we can save time). */
5451 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
5452 struct regcache
*regcache
, int regno
, int all
)
5454 struct usrregs_info
*usr
= regs_info
->usrregs
;
5458 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5459 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5460 fetch_register (usr
, regcache
, regno
);
5463 fetch_register (usr
, regcache
, regno
);
5466 /* Store our register values back into the inferior.
5467 If REGNO is -1, do this for all registers, skipping any that are
5468 assumed to have been saved by regsets_store_inferior_registers,
5469 unless ALL is non-zero.
5470 Otherwise, REGNO specifies which register (so we can save time). */
5472 usr_store_inferior_registers (const struct regs_info
*regs_info
,
5473 struct regcache
*regcache
, int regno
, int all
)
5475 struct usrregs_info
*usr
= regs_info
->usrregs
;
5479 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5480 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5481 store_register (usr
, regcache
, regno
);
5484 store_register (usr
, regcache
, regno
);
5487 #else /* !HAVE_LINUX_USRREGS */
5489 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5490 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5496 linux_fetch_registers (struct regcache
*regcache
, int regno
)
5500 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5504 if (the_low_target
.fetch_register
!= NULL
5505 && regs_info
->usrregs
!= NULL
)
5506 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5507 (*the_low_target
.fetch_register
) (regcache
, regno
);
5509 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5510 if (regs_info
->usrregs
!= NULL
)
5511 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5515 if (the_low_target
.fetch_register
!= NULL
5516 && (*the_low_target
.fetch_register
) (regcache
, regno
))
5519 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5521 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5523 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5524 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5529 linux_store_registers (struct regcache
*regcache
, int regno
)
5533 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5537 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5539 if (regs_info
->usrregs
!= NULL
)
5540 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5544 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5546 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5548 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5549 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5554 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5555 to debugger memory starting at MYADDR. */
5558 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5560 int pid
= lwpid_of (current_thread
);
5561 register PTRACE_XFER_TYPE
*buffer
;
5562 register CORE_ADDR addr
;
5569 /* Try using /proc. Don't bother for one word. */
5570 if (len
>= 3 * sizeof (long))
5574 /* We could keep this file open and cache it - possibly one per
5575 thread. That requires some juggling, but is even faster. */
5576 sprintf (filename
, "/proc/%d/mem", pid
);
5577 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5581 /* If pread64 is available, use it. It's faster if the kernel
5582 supports it (only one syscall), and it's 64-bit safe even on
5583 32-bit platforms (for instance, SPARC debugging a SPARC64
5586 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5589 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5590 bytes
= read (fd
, myaddr
, len
);
5597 /* Some data was read, we'll try to get the rest with ptrace. */
5607 /* Round starting address down to longword boundary. */
5608 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5609 /* Round ending address up; get number of longwords that makes. */
5610 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5611 / sizeof (PTRACE_XFER_TYPE
));
5612 /* Allocate buffer of that many longwords. */
5613 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5615 /* Read all the longwords */
5617 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5619 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5620 about coercing an 8 byte integer to a 4 byte pointer. */
5621 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5622 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5623 (PTRACE_TYPE_ARG4
) 0);
5629 /* Copy appropriate bytes out of the buffer. */
5632 i
*= sizeof (PTRACE_XFER_TYPE
);
5633 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5635 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5642 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5643 memory at MEMADDR. On failure (cannot write to the inferior)
5644 returns the value of errno. Always succeeds if LEN is zero. */
5647 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5650 /* Round starting address down to longword boundary. */
5651 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5652 /* Round ending address up; get number of longwords that makes. */
5654 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5655 / sizeof (PTRACE_XFER_TYPE
);
5657 /* Allocate buffer of that many longwords. */
5658 register PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5660 int pid
= lwpid_of (current_thread
);
5664 /* Zero length write always succeeds. */
5670 /* Dump up to four bytes. */
5671 char str
[4 * 2 + 1];
5673 int dump
= len
< 4 ? len
: 4;
5675 for (i
= 0; i
< dump
; i
++)
5677 sprintf (p
, "%02x", myaddr
[i
]);
5682 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5683 str
, (long) memaddr
, pid
);
5686 /* Fill start and end extra bytes of buffer with existing memory data. */
5689 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5690 about coercing an 8 byte integer to a 4 byte pointer. */
5691 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5692 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5693 (PTRACE_TYPE_ARG4
) 0);
5701 = ptrace (PTRACE_PEEKTEXT
, pid
,
5702 /* Coerce to a uintptr_t first to avoid potential gcc warning
5703 about coercing an 8 byte integer to a 4 byte pointer. */
5704 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5705 * sizeof (PTRACE_XFER_TYPE
)),
5706 (PTRACE_TYPE_ARG4
) 0);
5711 /* Copy data to be written over corresponding part of buffer. */
5713 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5716 /* Write the entire buffer. */
5718 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5721 ptrace (PTRACE_POKETEXT
, pid
,
5722 /* Coerce to a uintptr_t first to avoid potential gcc warning
5723 about coercing an 8 byte integer to a 4 byte pointer. */
5724 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5725 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5734 linux_look_up_symbols (void)
5736 #ifdef USE_THREAD_DB
5737 struct process_info
*proc
= current_process ();
5739 if (proc
->priv
->thread_db
!= NULL
)
5747 linux_request_interrupt (void)
5749 extern unsigned long signal_pid
;
5751 /* Send a SIGINT to the process group. This acts just like the user
5752 typed a ^C on the controlling terminal. */
5753 kill (-signal_pid
, SIGINT
);
5756 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5757 to debugger memory starting at MYADDR. */
5760 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5762 char filename
[PATH_MAX
];
5764 int pid
= lwpid_of (current_thread
);
5766 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5768 fd
= open (filename
, O_RDONLY
);
5772 if (offset
!= (CORE_ADDR
) 0
5773 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5776 n
= read (fd
, myaddr
, len
);
5783 /* These breakpoint and watchpoint related wrapper functions simply
5784 pass on the function call if the target has registered a
5785 corresponding function. */
5788 linux_supports_z_point_type (char z_type
)
5790 return (the_low_target
.supports_z_point_type
!= NULL
5791 && the_low_target
.supports_z_point_type (z_type
));
5795 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5796 int size
, struct raw_breakpoint
*bp
)
5798 if (type
== raw_bkpt_type_sw
)
5799 return insert_memory_breakpoint (bp
);
5800 else if (the_low_target
.insert_point
!= NULL
)
5801 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5803 /* Unsupported (see target.h). */
5808 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5809 int size
, struct raw_breakpoint
*bp
)
5811 if (type
== raw_bkpt_type_sw
)
5812 return remove_memory_breakpoint (bp
);
5813 else if (the_low_target
.remove_point
!= NULL
)
5814 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5816 /* Unsupported (see target.h). */
5820 /* Implement the to_stopped_by_sw_breakpoint target_ops
5824 linux_stopped_by_sw_breakpoint (void)
5826 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5828 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5831 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5835 linux_supports_stopped_by_sw_breakpoint (void)
5837 return USE_SIGTRAP_SIGINFO
;
5840 /* Implement the to_stopped_by_hw_breakpoint target_ops
5844 linux_stopped_by_hw_breakpoint (void)
5846 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5848 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5851 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5855 linux_supports_stopped_by_hw_breakpoint (void)
5857 return USE_SIGTRAP_SIGINFO
;
5860 /* Implement the supports_hardware_single_step target_ops method. */
5863 linux_supports_hardware_single_step (void)
5865 return can_hardware_single_step ();
5869 linux_supports_software_single_step (void)
5871 return can_software_single_step ();
5875 linux_stopped_by_watchpoint (void)
5877 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5879 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5883 linux_stopped_data_address (void)
5885 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5887 return lwp
->stopped_data_address
;
5890 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5891 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5892 && defined(PT_TEXT_END_ADDR)
5894 /* This is only used for targets that define PT_TEXT_ADDR,
5895 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5896 the target has different ways of acquiring this information, like
5899 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5900 to tell gdb about. */
5903 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5905 unsigned long text
, text_end
, data
;
5906 int pid
= lwpid_of (current_thread
);
5910 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5911 (PTRACE_TYPE_ARG4
) 0);
5912 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5913 (PTRACE_TYPE_ARG4
) 0);
5914 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5915 (PTRACE_TYPE_ARG4
) 0);
5919 /* Both text and data offsets produced at compile-time (and so
5920 used by gdb) are relative to the beginning of the program,
5921 with the data segment immediately following the text segment.
5922 However, the actual runtime layout in memory may put the data
5923 somewhere else, so when we send gdb a data base-address, we
5924 use the real data base address and subtract the compile-time
5925 data base-address from it (which is just the length of the
5926 text segment). BSS immediately follows data in both
5929 *data_p
= data
- (text_end
- text
);
5938 linux_qxfer_osdata (const char *annex
,
5939 unsigned char *readbuf
, unsigned const char *writebuf
,
5940 CORE_ADDR offset
, int len
)
5942 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5945 /* Convert a native/host siginfo object, into/from the siginfo in the
5946 layout of the inferiors' architecture. */
5949 siginfo_fixup (siginfo_t
*siginfo
, gdb_byte
*inf_siginfo
, int direction
)
5953 if (the_low_target
.siginfo_fixup
!= NULL
)
5954 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5956 /* If there was no callback, or the callback didn't do anything,
5957 then just do a straight memcpy. */
5961 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5963 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5968 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
5969 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
5973 gdb_byte inf_siginfo
[sizeof (siginfo_t
)];
5975 if (current_thread
== NULL
)
5978 pid
= lwpid_of (current_thread
);
5981 debug_printf ("%s siginfo for lwp %d.\n",
5982 readbuf
!= NULL
? "Reading" : "Writing",
5985 if (offset
>= sizeof (siginfo
))
5988 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5991 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5992 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5993 inferior with a 64-bit GDBSERVER should look the same as debugging it
5994 with a 32-bit GDBSERVER, we need to convert it. */
5995 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
5997 if (offset
+ len
> sizeof (siginfo
))
5998 len
= sizeof (siginfo
) - offset
;
6000 if (readbuf
!= NULL
)
6001 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
6004 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
6006 /* Convert back to ptrace layout before flushing it out. */
6007 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
6009 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6016 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6017 so we notice when children change state; as the handler for the
6018 sigsuspend in my_waitpid. */
6021 sigchld_handler (int signo
)
6023 int old_errno
= errno
;
6029 /* fprintf is not async-signal-safe, so call write
6031 if (write (2, "sigchld_handler\n",
6032 sizeof ("sigchld_handler\n") - 1) < 0)
6033 break; /* just ignore */
6037 if (target_is_async_p ())
6038 async_file_mark (); /* trigger a linux_wait */
6044 linux_supports_non_stop (void)
6050 linux_async (int enable
)
6052 int previous
= target_is_async_p ();
6055 debug_printf ("linux_async (%d), previous=%d\n",
6058 if (previous
!= enable
)
6061 sigemptyset (&mask
);
6062 sigaddset (&mask
, SIGCHLD
);
6064 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
6068 if (pipe (linux_event_pipe
) == -1)
6070 linux_event_pipe
[0] = -1;
6071 linux_event_pipe
[1] = -1;
6072 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6074 warning ("creating event pipe failed.");
6078 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
6079 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
6081 /* Register the event loop handler. */
6082 add_file_handler (linux_event_pipe
[0],
6083 handle_target_event
, NULL
);
6085 /* Always trigger a linux_wait. */
6090 delete_file_handler (linux_event_pipe
[0]);
6092 close (linux_event_pipe
[0]);
6093 close (linux_event_pipe
[1]);
6094 linux_event_pipe
[0] = -1;
6095 linux_event_pipe
[1] = -1;
6098 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6105 linux_start_non_stop (int nonstop
)
6107 /* Register or unregister from event-loop accordingly. */
6108 linux_async (nonstop
);
6110 if (target_is_async_p () != (nonstop
!= 0))
6117 linux_supports_multi_process (void)
6122 /* Check if fork events are supported. */
6125 linux_supports_fork_events (void)
6127 return linux_supports_tracefork ();
6130 /* Check if vfork events are supported. */
6133 linux_supports_vfork_events (void)
6135 return linux_supports_tracefork ();
6138 /* Check if exec events are supported. */
6141 linux_supports_exec_events (void)
6143 return linux_supports_traceexec ();
6146 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
6147 options for the specified lwp. */
6150 reset_lwp_ptrace_options_callback (struct inferior_list_entry
*entry
,
6153 struct thread_info
*thread
= (struct thread_info
*) entry
;
6154 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6158 /* Stop the lwp so we can modify its ptrace options. */
6159 lwp
->must_set_ptrace_flags
= 1;
6160 linux_stop_lwp (lwp
);
6164 /* Already stopped; go ahead and set the ptrace options. */
6165 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6166 int options
= linux_low_ptrace_options (proc
->attached
);
6168 linux_enable_event_reporting (lwpid_of (thread
), options
);
6169 lwp
->must_set_ptrace_flags
= 0;
6175 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6176 ptrace flags for all inferiors. This is in case the new GDB connection
6177 doesn't support the same set of events that the previous one did. */
6180 linux_handle_new_gdb_connection (void)
6184 /* Request that all the lwps reset their ptrace options. */
6185 find_inferior (&all_threads
, reset_lwp_ptrace_options_callback
, &pid
);
6189 linux_supports_disable_randomization (void)
6191 #ifdef HAVE_PERSONALITY
6199 linux_supports_agent (void)
6205 linux_supports_range_stepping (void)
6207 if (*the_low_target
.supports_range_stepping
== NULL
)
6210 return (*the_low_target
.supports_range_stepping
) ();
6213 /* Enumerate spufs IDs for process PID. */
6215 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
6221 struct dirent
*entry
;
6223 sprintf (path
, "/proc/%ld/fd", pid
);
6224 dir
= opendir (path
);
6229 while ((entry
= readdir (dir
)) != NULL
)
6235 fd
= atoi (entry
->d_name
);
6239 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
6240 if (stat (path
, &st
) != 0)
6242 if (!S_ISDIR (st
.st_mode
))
6245 if (statfs (path
, &stfs
) != 0)
6247 if (stfs
.f_type
!= SPUFS_MAGIC
)
6250 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
6252 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
6262 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6263 object type, using the /proc file system. */
6265 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
6266 unsigned const char *writebuf
,
6267 CORE_ADDR offset
, int len
)
6269 long pid
= lwpid_of (current_thread
);
6274 if (!writebuf
&& !readbuf
)
6282 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
6285 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
6286 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
6291 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
6298 ret
= write (fd
, writebuf
, (size_t) len
);
6300 ret
= read (fd
, readbuf
, (size_t) len
);
6306 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6307 struct target_loadseg
6309 /* Core address to which the segment is mapped. */
6311 /* VMA recorded in the program header. */
6313 /* Size of this segment in memory. */
6317 # if defined PT_GETDSBT
6318 struct target_loadmap
6320 /* Protocol version number, must be zero. */
6322 /* Pointer to the DSBT table, its size, and the DSBT index. */
6323 unsigned *dsbt_table
;
6324 unsigned dsbt_size
, dsbt_index
;
6325 /* Number of segments in this map. */
6327 /* The actual memory map. */
6328 struct target_loadseg segs
[/*nsegs*/];
6330 # define LINUX_LOADMAP PT_GETDSBT
6331 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6332 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6334 struct target_loadmap
6336 /* Protocol version number, must be zero. */
6338 /* Number of segments in this map. */
6340 /* The actual memory map. */
6341 struct target_loadseg segs
[/*nsegs*/];
6343 # define LINUX_LOADMAP PTRACE_GETFDPIC
6344 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6345 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6349 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
6350 unsigned char *myaddr
, unsigned int len
)
6352 int pid
= lwpid_of (current_thread
);
6354 struct target_loadmap
*data
= NULL
;
6355 unsigned int actual_length
, copy_length
;
6357 if (strcmp (annex
, "exec") == 0)
6358 addr
= (int) LINUX_LOADMAP_EXEC
;
6359 else if (strcmp (annex
, "interp") == 0)
6360 addr
= (int) LINUX_LOADMAP_INTERP
;
6364 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6370 actual_length
= sizeof (struct target_loadmap
)
6371 + sizeof (struct target_loadseg
) * data
->nsegs
;
6373 if (offset
< 0 || offset
> actual_length
)
6376 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6377 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6381 # define linux_read_loadmap NULL
6382 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6385 linux_process_qsupported (char **features
, int count
)
6387 if (the_low_target
.process_qsupported
!= NULL
)
6388 the_low_target
.process_qsupported (features
, count
);
6392 linux_supports_catch_syscall (void)
6394 return (the_low_target
.get_syscall_trapinfo
!= NULL
6395 && linux_supports_tracesysgood ());
6399 linux_get_ipa_tdesc_idx (void)
6401 if (the_low_target
.get_ipa_tdesc_idx
== NULL
)
6404 return (*the_low_target
.get_ipa_tdesc_idx
) ();
6408 linux_supports_tracepoints (void)
6410 if (*the_low_target
.supports_tracepoints
== NULL
)
6413 return (*the_low_target
.supports_tracepoints
) ();
6417 linux_read_pc (struct regcache
*regcache
)
6419 if (the_low_target
.get_pc
== NULL
)
6422 return (*the_low_target
.get_pc
) (regcache
);
6426 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
6428 gdb_assert (the_low_target
.set_pc
!= NULL
);
6430 (*the_low_target
.set_pc
) (regcache
, pc
);
6434 linux_thread_stopped (struct thread_info
*thread
)
6436 return get_thread_lwp (thread
)->stopped
;
6439 /* This exposes stop-all-threads functionality to other modules. */
6442 linux_pause_all (int freeze
)
6444 stop_all_lwps (freeze
, NULL
);
6447 /* This exposes unstop-all-threads functionality to other gdbserver
6451 linux_unpause_all (int unfreeze
)
6453 unstop_all_lwps (unfreeze
, NULL
);
6457 linux_prepare_to_access_memory (void)
6459 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6462 linux_pause_all (1);
6467 linux_done_accessing_memory (void)
6469 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6472 linux_unpause_all (1);
6476 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
6477 CORE_ADDR collector
,
6480 CORE_ADDR
*jump_entry
,
6481 CORE_ADDR
*trampoline
,
6482 ULONGEST
*trampoline_size
,
6483 unsigned char *jjump_pad_insn
,
6484 ULONGEST
*jjump_pad_insn_size
,
6485 CORE_ADDR
*adjusted_insn_addr
,
6486 CORE_ADDR
*adjusted_insn_addr_end
,
6489 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
6490 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
6491 jump_entry
, trampoline
, trampoline_size
,
6492 jjump_pad_insn
, jjump_pad_insn_size
,
6493 adjusted_insn_addr
, adjusted_insn_addr_end
,
6497 static struct emit_ops
*
6498 linux_emit_ops (void)
6500 if (the_low_target
.emit_ops
!= NULL
)
6501 return (*the_low_target
.emit_ops
) ();
6507 linux_get_min_fast_tracepoint_insn_len (void)
6509 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
6512 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6515 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6516 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6518 char filename
[PATH_MAX
];
6520 const int auxv_size
= is_elf64
6521 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6522 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6524 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6526 fd
= open (filename
, O_RDONLY
);
6532 while (read (fd
, buf
, auxv_size
) == auxv_size
6533 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6537 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6539 switch (aux
->a_type
)
6542 *phdr_memaddr
= aux
->a_un
.a_val
;
6545 *num_phdr
= aux
->a_un
.a_val
;
6551 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6553 switch (aux
->a_type
)
6556 *phdr_memaddr
= aux
->a_un
.a_val
;
6559 *num_phdr
= aux
->a_un
.a_val
;
6567 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6569 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6570 "phdr_memaddr = %ld, phdr_num = %d",
6571 (long) *phdr_memaddr
, *num_phdr
);
6578 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6581 get_dynamic (const int pid
, const int is_elf64
)
6583 CORE_ADDR phdr_memaddr
, relocation
;
6585 unsigned char *phdr_buf
;
6586 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6588 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6591 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6592 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6594 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6597 /* Compute relocation: it is expected to be 0 for "regular" executables,
6598 non-zero for PIE ones. */
6600 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6603 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6605 if (p
->p_type
== PT_PHDR
)
6606 relocation
= phdr_memaddr
- p
->p_vaddr
;
6610 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6612 if (p
->p_type
== PT_PHDR
)
6613 relocation
= phdr_memaddr
- p
->p_vaddr
;
6616 if (relocation
== -1)
6618 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6619 any real world executables, including PIE executables, have always
6620 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6621 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6622 or present DT_DEBUG anyway (fpc binaries are statically linked).
6624 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6626 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6631 for (i
= 0; i
< num_phdr
; i
++)
6635 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6637 if (p
->p_type
== PT_DYNAMIC
)
6638 return p
->p_vaddr
+ relocation
;
6642 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6644 if (p
->p_type
== PT_DYNAMIC
)
6645 return p
->p_vaddr
+ relocation
;
6652 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6653 can be 0 if the inferior does not yet have the library list initialized.
6654 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6655 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6658 get_r_debug (const int pid
, const int is_elf64
)
6660 CORE_ADDR dynamic_memaddr
;
6661 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6662 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6665 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6666 if (dynamic_memaddr
== 0)
6669 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6673 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6674 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6678 unsigned char buf
[sizeof (Elf64_Xword
)];
6682 #ifdef DT_MIPS_RLD_MAP
6683 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6685 if (linux_read_memory (dyn
->d_un
.d_val
,
6686 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6691 #endif /* DT_MIPS_RLD_MAP */
6692 #ifdef DT_MIPS_RLD_MAP_REL
6693 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6695 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6696 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6701 #endif /* DT_MIPS_RLD_MAP_REL */
6703 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6704 map
= dyn
->d_un
.d_val
;
6706 if (dyn
->d_tag
== DT_NULL
)
6711 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6712 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6716 unsigned char buf
[sizeof (Elf32_Word
)];
6720 #ifdef DT_MIPS_RLD_MAP
6721 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6723 if (linux_read_memory (dyn
->d_un
.d_val
,
6724 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6729 #endif /* DT_MIPS_RLD_MAP */
6730 #ifdef DT_MIPS_RLD_MAP_REL
6731 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6733 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6734 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6739 #endif /* DT_MIPS_RLD_MAP_REL */
6741 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6742 map
= dyn
->d_un
.d_val
;
6744 if (dyn
->d_tag
== DT_NULL
)
6748 dynamic_memaddr
+= dyn_size
;
6754 /* Read one pointer from MEMADDR in the inferior. */
6757 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6761 /* Go through a union so this works on either big or little endian
6762 hosts, when the inferior's pointer size is smaller than the size
6763 of CORE_ADDR. It is assumed the inferior's endianness is the
6764 same of the superior's. */
6767 CORE_ADDR core_addr
;
6772 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6775 if (ptr_size
== sizeof (CORE_ADDR
))
6776 *ptr
= addr
.core_addr
;
6777 else if (ptr_size
== sizeof (unsigned int))
6780 gdb_assert_not_reached ("unhandled pointer size");
6785 struct link_map_offsets
6787 /* Offset and size of r_debug.r_version. */
6788 int r_version_offset
;
6790 /* Offset and size of r_debug.r_map. */
6793 /* Offset to l_addr field in struct link_map. */
6796 /* Offset to l_name field in struct link_map. */
6799 /* Offset to l_ld field in struct link_map. */
6802 /* Offset to l_next field in struct link_map. */
6805 /* Offset to l_prev field in struct link_map. */
6809 /* Construct qXfer:libraries-svr4:read reply. */
6812 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6813 unsigned const char *writebuf
,
6814 CORE_ADDR offset
, int len
)
6817 unsigned document_len
;
6818 struct process_info_private
*const priv
= current_process ()->priv
;
6819 char filename
[PATH_MAX
];
6822 static const struct link_map_offsets lmo_32bit_offsets
=
6824 0, /* r_version offset. */
6825 4, /* r_debug.r_map offset. */
6826 0, /* l_addr offset in link_map. */
6827 4, /* l_name offset in link_map. */
6828 8, /* l_ld offset in link_map. */
6829 12, /* l_next offset in link_map. */
6830 16 /* l_prev offset in link_map. */
6833 static const struct link_map_offsets lmo_64bit_offsets
=
6835 0, /* r_version offset. */
6836 8, /* r_debug.r_map offset. */
6837 0, /* l_addr offset in link_map. */
6838 8, /* l_name offset in link_map. */
6839 16, /* l_ld offset in link_map. */
6840 24, /* l_next offset in link_map. */
6841 32 /* l_prev offset in link_map. */
6843 const struct link_map_offsets
*lmo
;
6844 unsigned int machine
;
6846 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6847 int allocated
= 1024;
6849 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6850 int header_done
= 0;
6852 if (writebuf
!= NULL
)
6854 if (readbuf
== NULL
)
6857 pid
= lwpid_of (current_thread
);
6858 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6859 is_elf64
= elf_64_file_p (filename
, &machine
);
6860 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6861 ptr_size
= is_elf64
? 8 : 4;
6863 while (annex
[0] != '\0')
6869 sep
= strchr (annex
, '=');
6874 if (len
== 5 && startswith (annex
, "start"))
6876 else if (len
== 4 && startswith (annex
, "prev"))
6880 annex
= strchr (sep
, ';');
6887 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6894 if (priv
->r_debug
== 0)
6895 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6897 /* We failed to find DT_DEBUG. Such situation will not change
6898 for this inferior - do not retry it. Report it to GDB as
6899 E01, see for the reasons at the GDB solib-svr4.c side. */
6900 if (priv
->r_debug
== (CORE_ADDR
) -1)
6903 if (priv
->r_debug
!= 0)
6905 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6906 (unsigned char *) &r_version
,
6907 sizeof (r_version
)) != 0
6910 warning ("unexpected r_debug version %d", r_version
);
6912 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6913 &lm_addr
, ptr_size
) != 0)
6915 warning ("unable to read r_map from 0x%lx",
6916 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6921 document
= (char *) xmalloc (allocated
);
6922 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
6923 p
= document
+ strlen (document
);
6926 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6927 &l_name
, ptr_size
) == 0
6928 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6929 &l_addr
, ptr_size
) == 0
6930 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6931 &l_ld
, ptr_size
) == 0
6932 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6933 &l_prev
, ptr_size
) == 0
6934 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6935 &l_next
, ptr_size
) == 0)
6937 unsigned char libname
[PATH_MAX
];
6939 if (lm_prev
!= l_prev
)
6941 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6942 (long) lm_prev
, (long) l_prev
);
6946 /* Ignore the first entry even if it has valid name as the first entry
6947 corresponds to the main executable. The first entry should not be
6948 skipped if the dynamic loader was loaded late by a static executable
6949 (see solib-svr4.c parameter ignore_first). But in such case the main
6950 executable does not have PT_DYNAMIC present and this function already
6951 exited above due to failed get_r_debug. */
6954 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6959 /* Not checking for error because reading may stop before
6960 we've got PATH_MAX worth of characters. */
6962 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6963 libname
[sizeof (libname
) - 1] = '\0';
6964 if (libname
[0] != '\0')
6966 /* 6x the size for xml_escape_text below. */
6967 size_t len
= 6 * strlen ((char *) libname
);
6972 /* Terminate `<library-list-svr4'. */
6977 while (allocated
< p
- document
+ len
+ 200)
6979 /* Expand to guarantee sufficient storage. */
6980 uintptr_t document_len
= p
- document
;
6982 document
= (char *) xrealloc (document
, 2 * allocated
);
6984 p
= document
+ document_len
;
6987 name
= xml_escape_text ((char *) libname
);
6988 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
6989 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6990 name
, (unsigned long) lm_addr
,
6991 (unsigned long) l_addr
, (unsigned long) l_ld
);
7002 /* Empty list; terminate `<library-list-svr4'. */
7006 strcpy (p
, "</library-list-svr4>");
7008 document_len
= strlen (document
);
7009 if (offset
< document_len
)
7010 document_len
-= offset
;
7013 if (len
> document_len
)
7016 memcpy (readbuf
, document
+ offset
, len
);
7022 #ifdef HAVE_LINUX_BTRACE
7024 /* See to_disable_btrace target method. */
7027 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
7029 enum btrace_error err
;
7031 err
= linux_disable_btrace (tinfo
);
7032 return (err
== BTRACE_ERR_NONE
? 0 : -1);
7035 /* Encode an Intel Processor Trace configuration. */
7038 linux_low_encode_pt_config (struct buffer
*buffer
,
7039 const struct btrace_data_pt_config
*config
)
7041 buffer_grow_str (buffer
, "<pt-config>\n");
7043 switch (config
->cpu
.vendor
)
7046 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7047 "model=\"%u\" stepping=\"%u\"/>\n",
7048 config
->cpu
.family
, config
->cpu
.model
,
7049 config
->cpu
.stepping
);
7056 buffer_grow_str (buffer
, "</pt-config>\n");
7059 /* Encode a raw buffer. */
7062 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
7068 /* We use hex encoding - see common/rsp-low.h. */
7069 buffer_grow_str (buffer
, "<raw>\n");
7075 elem
[0] = tohex ((*data
>> 4) & 0xf);
7076 elem
[1] = tohex (*data
++ & 0xf);
7078 buffer_grow (buffer
, elem
, 2);
7081 buffer_grow_str (buffer
, "</raw>\n");
7084 /* See to_read_btrace target method. */
7087 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
7088 enum btrace_read_type type
)
7090 struct btrace_data btrace
;
7091 struct btrace_block
*block
;
7092 enum btrace_error err
;
7095 btrace_data_init (&btrace
);
7097 err
= linux_read_btrace (&btrace
, tinfo
, type
);
7098 if (err
!= BTRACE_ERR_NONE
)
7100 if (err
== BTRACE_ERR_OVERFLOW
)
7101 buffer_grow_str0 (buffer
, "E.Overflow.");
7103 buffer_grow_str0 (buffer
, "E.Generic Error.");
7108 switch (btrace
.format
)
7110 case BTRACE_FORMAT_NONE
:
7111 buffer_grow_str0 (buffer
, "E.No Trace.");
7114 case BTRACE_FORMAT_BTS
:
7115 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7116 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7119 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
7121 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7122 paddress (block
->begin
), paddress (block
->end
));
7124 buffer_grow_str0 (buffer
, "</btrace>\n");
7127 case BTRACE_FORMAT_PT
:
7128 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7129 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7130 buffer_grow_str (buffer
, "<pt>\n");
7132 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
7134 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
7135 btrace
.variant
.pt
.size
);
7137 buffer_grow_str (buffer
, "</pt>\n");
7138 buffer_grow_str0 (buffer
, "</btrace>\n");
7142 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
7146 btrace_data_fini (&btrace
);
7150 btrace_data_fini (&btrace
);
7154 /* See to_btrace_conf target method. */
7157 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
7158 struct buffer
*buffer
)
7160 const struct btrace_config
*conf
;
7162 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7163 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7165 conf
= linux_btrace_conf (tinfo
);
7168 switch (conf
->format
)
7170 case BTRACE_FORMAT_NONE
:
7173 case BTRACE_FORMAT_BTS
:
7174 buffer_xml_printf (buffer
, "<bts");
7175 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7176 buffer_xml_printf (buffer
, " />\n");
7179 case BTRACE_FORMAT_PT
:
7180 buffer_xml_printf (buffer
, "<pt");
7181 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7182 buffer_xml_printf (buffer
, "/>\n");
7187 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7190 #endif /* HAVE_LINUX_BTRACE */
7192 /* See nat/linux-nat.h. */
7195 current_lwp_ptid (void)
7197 return ptid_of (current_thread
);
7200 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7203 linux_breakpoint_kind_from_pc (CORE_ADDR
*pcptr
)
7205 if (the_low_target
.breakpoint_kind_from_pc
!= NULL
)
7206 return (*the_low_target
.breakpoint_kind_from_pc
) (pcptr
);
7208 return default_breakpoint_kind_from_pc (pcptr
);
7211 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7213 static const gdb_byte
*
7214 linux_sw_breakpoint_from_kind (int kind
, int *size
)
7216 gdb_assert (the_low_target
.sw_breakpoint_from_kind
!= NULL
);
7218 return (*the_low_target
.sw_breakpoint_from_kind
) (kind
, size
);
7221 /* Implementation of the target_ops method
7222 "breakpoint_kind_from_current_state". */
7225 linux_breakpoint_kind_from_current_state (CORE_ADDR
*pcptr
)
7227 if (the_low_target
.breakpoint_kind_from_current_state
!= NULL
)
7228 return (*the_low_target
.breakpoint_kind_from_current_state
) (pcptr
);
7230 return linux_breakpoint_kind_from_pc (pcptr
);
7233 /* Default implementation of linux_target_ops method "set_pc" for
7234 32-bit pc register which is literally named "pc". */
7237 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
7239 uint32_t newpc
= pc
;
7241 supply_register_by_name (regcache
, "pc", &newpc
);
7244 /* Default implementation of linux_target_ops method "get_pc" for
7245 32-bit pc register which is literally named "pc". */
7248 linux_get_pc_32bit (struct regcache
*regcache
)
7252 collect_register_by_name (regcache
, "pc", &pc
);
7254 debug_printf ("stop pc is 0x%" PRIx32
"\n", pc
);
7258 /* Default implementation of linux_target_ops method "set_pc" for
7259 64-bit pc register which is literally named "pc". */
7262 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
7264 uint64_t newpc
= pc
;
7266 supply_register_by_name (regcache
, "pc", &newpc
);
7269 /* Default implementation of linux_target_ops method "get_pc" for
7270 64-bit pc register which is literally named "pc". */
7273 linux_get_pc_64bit (struct regcache
*regcache
)
7277 collect_register_by_name (regcache
, "pc", &pc
);
7279 debug_printf ("stop pc is 0x%" PRIx64
"\n", pc
);
7284 static struct target_ops linux_target_ops
= {
7285 linux_create_inferior
,
7286 linux_post_create_inferior
,
7295 linux_fetch_registers
,
7296 linux_store_registers
,
7297 linux_prepare_to_access_memory
,
7298 linux_done_accessing_memory
,
7301 linux_look_up_symbols
,
7302 linux_request_interrupt
,
7304 linux_supports_z_point_type
,
7307 linux_stopped_by_sw_breakpoint
,
7308 linux_supports_stopped_by_sw_breakpoint
,
7309 linux_stopped_by_hw_breakpoint
,
7310 linux_supports_stopped_by_hw_breakpoint
,
7311 linux_supports_hardware_single_step
,
7312 linux_stopped_by_watchpoint
,
7313 linux_stopped_data_address
,
7314 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7315 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7316 && defined(PT_TEXT_END_ADDR)
7321 #ifdef USE_THREAD_DB
7322 thread_db_get_tls_address
,
7327 hostio_last_error_from_errno
,
7330 linux_supports_non_stop
,
7332 linux_start_non_stop
,
7333 linux_supports_multi_process
,
7334 linux_supports_fork_events
,
7335 linux_supports_vfork_events
,
7336 linux_supports_exec_events
,
7337 linux_handle_new_gdb_connection
,
7338 #ifdef USE_THREAD_DB
7339 thread_db_handle_monitor_command
,
7343 linux_common_core_of_thread
,
7345 linux_process_qsupported
,
7346 linux_supports_tracepoints
,
7349 linux_thread_stopped
,
7353 linux_stabilize_threads
,
7354 linux_install_fast_tracepoint_jump_pad
,
7356 linux_supports_disable_randomization
,
7357 linux_get_min_fast_tracepoint_insn_len
,
7358 linux_qxfer_libraries_svr4
,
7359 linux_supports_agent
,
7360 #ifdef HAVE_LINUX_BTRACE
7361 linux_supports_btrace
,
7362 linux_enable_btrace
,
7363 linux_low_disable_btrace
,
7364 linux_low_read_btrace
,
7365 linux_low_btrace_conf
,
7373 linux_supports_range_stepping
,
7374 linux_proc_pid_to_exec_file
,
7375 linux_mntns_open_cloexec
,
7377 linux_mntns_readlink
,
7378 linux_breakpoint_kind_from_pc
,
7379 linux_sw_breakpoint_from_kind
,
7380 linux_proc_tid_get_name
,
7381 linux_breakpoint_kind_from_current_state
,
7382 linux_supports_software_single_step
,
7383 linux_supports_catch_syscall
,
7384 linux_get_ipa_tdesc_idx
,
7387 #ifdef HAVE_LINUX_REGSETS
7389 initialize_regsets_info (struct regsets_info
*info
)
7391 for (info
->num_regsets
= 0;
7392 info
->regsets
[info
->num_regsets
].size
>= 0;
7393 info
->num_regsets
++)
7399 initialize_low (void)
7401 struct sigaction sigchld_action
;
7403 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7404 set_target_ops (&linux_target_ops
);
7406 linux_ptrace_init_warnings ();
7408 sigchld_action
.sa_handler
= sigchld_handler
;
7409 sigemptyset (&sigchld_action
.sa_mask
);
7410 sigchld_action
.sa_flags
= SA_RESTART
;
7411 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7413 initialize_low_arch ();
7415 linux_check_ptrace_features ();