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 /* Return true if THREAD is doing hardware single step. */
2501 maybe_hw_step (struct thread_info
*thread
)
2503 if (can_hardware_single_step ())
2507 struct process_info
*proc
= get_thread_process (thread
);
2509 /* GDBserver must insert reinsert breakpoint for software
2511 gdb_assert (has_reinsert_breakpoints (proc
));
2516 /* Resume LWPs that are currently stopped without any pending status
2517 to report, but are resumed from the core's perspective. */
2520 resume_stopped_resumed_lwps (struct inferior_list_entry
*entry
)
2522 struct thread_info
*thread
= (struct thread_info
*) entry
;
2523 struct lwp_info
*lp
= get_thread_lwp (thread
);
2527 && !lp
->status_pending_p
2528 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2530 int step
= thread
->last_resume_kind
== resume_step
;
2533 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2534 target_pid_to_str (ptid_of (thread
)),
2535 paddress (lp
->stop_pc
),
2538 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2542 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2543 match FILTER_PTID (leaving others pending). The PTIDs can be:
2544 minus_one_ptid, to specify any child; a pid PTID, specifying all
2545 lwps of a thread group; or a PTID representing a single lwp. Store
2546 the stop status through the status pointer WSTAT. OPTIONS is
2547 passed to the waitpid call. Return 0 if no event was found and
2548 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2549 was found. Return the PID of the stopped child otherwise. */
2552 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2553 int *wstatp
, int options
)
2555 struct thread_info
*event_thread
;
2556 struct lwp_info
*event_child
, *requested_child
;
2557 sigset_t block_mask
, prev_mask
;
2560 /* N.B. event_thread points to the thread_info struct that contains
2561 event_child. Keep them in sync. */
2562 event_thread
= NULL
;
2564 requested_child
= NULL
;
2566 /* Check for a lwp with a pending status. */
2568 if (ptid_equal (filter_ptid
, minus_one_ptid
) || ptid_is_pid (filter_ptid
))
2570 event_thread
= (struct thread_info
*)
2571 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2572 if (event_thread
!= NULL
)
2573 event_child
= get_thread_lwp (event_thread
);
2574 if (debug_threads
&& event_thread
)
2575 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2577 else if (!ptid_equal (filter_ptid
, null_ptid
))
2579 requested_child
= find_lwp_pid (filter_ptid
);
2581 if (stopping_threads
== NOT_STOPPING_THREADS
2582 && requested_child
->status_pending_p
2583 && requested_child
->collecting_fast_tracepoint
)
2585 enqueue_one_deferred_signal (requested_child
,
2586 &requested_child
->status_pending
);
2587 requested_child
->status_pending_p
= 0;
2588 requested_child
->status_pending
= 0;
2589 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2592 if (requested_child
->suspended
2593 && requested_child
->status_pending_p
)
2595 internal_error (__FILE__
, __LINE__
,
2596 "requesting an event out of a"
2597 " suspended child?");
2600 if (requested_child
->status_pending_p
)
2602 event_child
= requested_child
;
2603 event_thread
= get_lwp_thread (event_child
);
2607 if (event_child
!= NULL
)
2610 debug_printf ("Got an event from pending child %ld (%04x)\n",
2611 lwpid_of (event_thread
), event_child
->status_pending
);
2612 *wstatp
= event_child
->status_pending
;
2613 event_child
->status_pending_p
= 0;
2614 event_child
->status_pending
= 0;
2615 current_thread
= event_thread
;
2616 return lwpid_of (event_thread
);
2619 /* But if we don't find a pending event, we'll have to wait.
2621 We only enter this loop if no process has a pending wait status.
2622 Thus any action taken in response to a wait status inside this
2623 loop is responding as soon as we detect the status, not after any
2626 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2627 all signals while here. */
2628 sigfillset (&block_mask
);
2629 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2631 /* Always pull all events out of the kernel. We'll randomly select
2632 an event LWP out of all that have events, to prevent
2634 while (event_child
== NULL
)
2638 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2641 - If the thread group leader exits while other threads in the
2642 thread group still exist, waitpid(TGID, ...) hangs. That
2643 waitpid won't return an exit status until the other threads
2644 in the group are reaped.
2646 - When a non-leader thread execs, that thread just vanishes
2647 without reporting an exit (so we'd hang if we waited for it
2648 explicitly in that case). The exec event is reported to
2651 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2654 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2655 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2661 debug_printf ("LLW: waitpid %ld received %s\n",
2662 (long) ret
, status_to_str (*wstatp
));
2665 /* Filter all events. IOW, leave all events pending. We'll
2666 randomly select an event LWP out of all that have events
2668 linux_low_filter_event (ret
, *wstatp
);
2669 /* Retry until nothing comes out of waitpid. A single
2670 SIGCHLD can indicate more than one child stopped. */
2674 /* Now that we've pulled all events out of the kernel, resume
2675 LWPs that don't have an interesting event to report. */
2676 if (stopping_threads
== NOT_STOPPING_THREADS
)
2677 for_each_inferior (&all_threads
, resume_stopped_resumed_lwps
);
2679 /* ... and find an LWP with a status to report to the core, if
2681 event_thread
= (struct thread_info
*)
2682 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2683 if (event_thread
!= NULL
)
2685 event_child
= get_thread_lwp (event_thread
);
2686 *wstatp
= event_child
->status_pending
;
2687 event_child
->status_pending_p
= 0;
2688 event_child
->status_pending
= 0;
2692 /* Check for zombie thread group leaders. Those can't be reaped
2693 until all other threads in the thread group are. */
2694 check_zombie_leaders ();
2696 /* If there are no resumed children left in the set of LWPs we
2697 want to wait for, bail. We can't just block in
2698 waitpid/sigsuspend, because lwps might have been left stopped
2699 in trace-stop state, and we'd be stuck forever waiting for
2700 their status to change (which would only happen if we resumed
2701 them). Even if WNOHANG is set, this return code is preferred
2702 over 0 (below), as it is more detailed. */
2703 if ((find_inferior (&all_threads
,
2704 not_stopped_callback
,
2705 &wait_ptid
) == NULL
))
2708 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2709 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2713 /* No interesting event to report to the caller. */
2714 if ((options
& WNOHANG
))
2717 debug_printf ("WNOHANG set, no event found\n");
2719 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2723 /* Block until we get an event reported with SIGCHLD. */
2725 debug_printf ("sigsuspend'ing\n");
2727 sigsuspend (&prev_mask
);
2728 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2732 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2734 current_thread
= event_thread
;
2736 return lwpid_of (event_thread
);
2739 /* Wait for an event from child(ren) PTID. PTIDs can be:
2740 minus_one_ptid, to specify any child; a pid PTID, specifying all
2741 lwps of a thread group; or a PTID representing a single lwp. Store
2742 the stop status through the status pointer WSTAT. OPTIONS is
2743 passed to the waitpid call. Return 0 if no event was found and
2744 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2745 was found. Return the PID of the stopped child otherwise. */
2748 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2750 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2753 /* Count the LWP's that have had events. */
2756 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2758 struct thread_info
*thread
= (struct thread_info
*) entry
;
2759 struct lwp_info
*lp
= get_thread_lwp (thread
);
2760 int *count
= (int *) data
;
2762 gdb_assert (count
!= NULL
);
2764 /* Count only resumed LWPs that have an event pending. */
2765 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2766 && lp
->status_pending_p
)
2772 /* Select the LWP (if any) that is currently being single-stepped. */
2775 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2777 struct thread_info
*thread
= (struct thread_info
*) entry
;
2778 struct lwp_info
*lp
= get_thread_lwp (thread
);
2780 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2781 && thread
->last_resume_kind
== resume_step
2782 && lp
->status_pending_p
)
2788 /* Select the Nth LWP that has had an event. */
2791 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2793 struct thread_info
*thread
= (struct thread_info
*) entry
;
2794 struct lwp_info
*lp
= get_thread_lwp (thread
);
2795 int *selector
= (int *) data
;
2797 gdb_assert (selector
!= NULL
);
2799 /* Select only resumed LWPs that have an event pending. */
2800 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2801 && lp
->status_pending_p
)
2802 if ((*selector
)-- == 0)
2808 /* Select one LWP out of those that have events pending. */
2811 select_event_lwp (struct lwp_info
**orig_lp
)
2814 int random_selector
;
2815 struct thread_info
*event_thread
= NULL
;
2817 /* In all-stop, give preference to the LWP that is being
2818 single-stepped. There will be at most one, and it's the LWP that
2819 the core is most interested in. If we didn't do this, then we'd
2820 have to handle pending step SIGTRAPs somehow in case the core
2821 later continues the previously-stepped thread, otherwise we'd
2822 report the pending SIGTRAP, and the core, not having stepped the
2823 thread, wouldn't understand what the trap was for, and therefore
2824 would report it to the user as a random signal. */
2828 = (struct thread_info
*) find_inferior (&all_threads
,
2829 select_singlestep_lwp_callback
,
2831 if (event_thread
!= NULL
)
2834 debug_printf ("SEL: Select single-step %s\n",
2835 target_pid_to_str (ptid_of (event_thread
)));
2838 if (event_thread
== NULL
)
2840 /* No single-stepping LWP. Select one at random, out of those
2841 which have had events. */
2843 /* First see how many events we have. */
2844 find_inferior (&all_threads
, count_events_callback
, &num_events
);
2845 gdb_assert (num_events
> 0);
2847 /* Now randomly pick a LWP out of those that have had
2849 random_selector
= (int)
2850 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2852 if (debug_threads
&& num_events
> 1)
2853 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2854 num_events
, random_selector
);
2857 = (struct thread_info
*) find_inferior (&all_threads
,
2858 select_event_lwp_callback
,
2862 if (event_thread
!= NULL
)
2864 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2866 /* Switch the event LWP. */
2867 *orig_lp
= event_lp
;
2871 /* Decrement the suspend count of an LWP. */
2874 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2876 struct thread_info
*thread
= (struct thread_info
*) entry
;
2877 struct lwp_info
*lwp
= get_thread_lwp (thread
);
2879 /* Ignore EXCEPT. */
2883 lwp_suspended_decr (lwp
);
2887 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2891 unsuspend_all_lwps (struct lwp_info
*except
)
2893 find_inferior (&all_threads
, unsuspend_one_lwp
, except
);
2896 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2897 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2899 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2900 static ptid_t
linux_wait_1 (ptid_t ptid
,
2901 struct target_waitstatus
*ourstatus
,
2902 int target_options
);
2904 /* Stabilize threads (move out of jump pads).
2906 If a thread is midway collecting a fast tracepoint, we need to
2907 finish the collection and move it out of the jump pad before
2908 reporting the signal.
2910 This avoids recursion while collecting (when a signal arrives
2911 midway, and the signal handler itself collects), which would trash
2912 the trace buffer. In case the user set a breakpoint in a signal
2913 handler, this avoids the backtrace showing the jump pad, etc..
2914 Most importantly, there are certain things we can't do safely if
2915 threads are stopped in a jump pad (or in its callee's). For
2918 - starting a new trace run. A thread still collecting the
2919 previous run, could trash the trace buffer when resumed. The trace
2920 buffer control structures would have been reset but the thread had
2921 no way to tell. The thread could even midway memcpy'ing to the
2922 buffer, which would mean that when resumed, it would clobber the
2923 trace buffer that had been set for a new run.
2925 - we can't rewrite/reuse the jump pads for new tracepoints
2926 safely. Say you do tstart while a thread is stopped midway while
2927 collecting. When the thread is later resumed, it finishes the
2928 collection, and returns to the jump pad, to execute the original
2929 instruction that was under the tracepoint jump at the time the
2930 older run had been started. If the jump pad had been rewritten
2931 since for something else in the new run, the thread would now
2932 execute the wrong / random instructions. */
2935 linux_stabilize_threads (void)
2937 struct thread_info
*saved_thread
;
2938 struct thread_info
*thread_stuck
;
2941 = (struct thread_info
*) find_inferior (&all_threads
,
2942 stuck_in_jump_pad_callback
,
2944 if (thread_stuck
!= NULL
)
2947 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2948 lwpid_of (thread_stuck
));
2952 saved_thread
= current_thread
;
2954 stabilizing_threads
= 1;
2957 for_each_inferior (&all_threads
, move_out_of_jump_pad_callback
);
2959 /* Loop until all are stopped out of the jump pads. */
2960 while (find_inferior (&all_threads
, lwp_running
, NULL
) != NULL
)
2962 struct target_waitstatus ourstatus
;
2963 struct lwp_info
*lwp
;
2966 /* Note that we go through the full wait even loop. While
2967 moving threads out of jump pad, we need to be able to step
2968 over internal breakpoints and such. */
2969 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2971 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2973 lwp
= get_thread_lwp (current_thread
);
2976 lwp_suspended_inc (lwp
);
2978 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2979 || current_thread
->last_resume_kind
== resume_stop
)
2981 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2982 enqueue_one_deferred_signal (lwp
, &wstat
);
2987 unsuspend_all_lwps (NULL
);
2989 stabilizing_threads
= 0;
2991 current_thread
= saved_thread
;
2996 = (struct thread_info
*) find_inferior (&all_threads
,
2997 stuck_in_jump_pad_callback
,
2999 if (thread_stuck
!= NULL
)
3000 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
3001 lwpid_of (thread_stuck
));
3005 /* Convenience function that is called when the kernel reports an
3006 event that is not passed out to GDB. */
3009 ignore_event (struct target_waitstatus
*ourstatus
)
3011 /* If we got an event, there may still be others, as a single
3012 SIGCHLD can indicate more than one child stopped. This forces
3013 another target_wait call. */
3016 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3020 /* Convenience function that is called when the kernel reports an exit
3021 event. This decides whether to report the event to GDB as a
3022 process exit event, a thread exit event, or to suppress the
3026 filter_exit_event (struct lwp_info
*event_child
,
3027 struct target_waitstatus
*ourstatus
)
3029 struct thread_info
*thread
= get_lwp_thread (event_child
);
3030 ptid_t ptid
= ptid_of (thread
);
3032 if (!last_thread_of_process_p (pid_of (thread
)))
3034 if (report_thread_events
)
3035 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
3037 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3039 delete_lwp (event_child
);
3044 /* Returns 1 if GDB is interested in any event_child syscalls. */
3047 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
3049 struct thread_info
*thread
= get_lwp_thread (event_child
);
3050 struct process_info
*proc
= get_thread_process (thread
);
3052 return !VEC_empty (int, proc
->syscalls_to_catch
);
3055 /* Returns 1 if GDB is interested in the event_child syscall.
3056 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
3059 gdb_catch_this_syscall_p (struct lwp_info
*event_child
)
3063 struct thread_info
*thread
= get_lwp_thread (event_child
);
3064 struct process_info
*proc
= get_thread_process (thread
);
3066 if (VEC_empty (int, proc
->syscalls_to_catch
))
3069 if (VEC_index (int, proc
->syscalls_to_catch
, 0) == ANY_SYSCALL
)
3072 get_syscall_trapinfo (event_child
, &sysno
, &sysret
);
3074 VEC_iterate (int, proc
->syscalls_to_catch
, i
, iter
);
3082 /* Wait for process, returns status. */
3085 linux_wait_1 (ptid_t ptid
,
3086 struct target_waitstatus
*ourstatus
, int target_options
)
3089 struct lwp_info
*event_child
;
3092 int step_over_finished
;
3093 int bp_explains_trap
;
3094 int maybe_internal_trap
;
3103 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
3106 /* Translate generic target options into linux options. */
3108 if (target_options
& TARGET_WNOHANG
)
3111 bp_explains_trap
= 0;
3114 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3116 /* Find a resumed LWP, if any. */
3117 if (find_inferior (&all_threads
,
3118 status_pending_p_callback
,
3119 &minus_one_ptid
) != NULL
)
3121 else if ((find_inferior (&all_threads
,
3122 not_stopped_callback
,
3123 &minus_one_ptid
) != NULL
))
3128 if (ptid_equal (step_over_bkpt
, null_ptid
))
3129 pid
= linux_wait_for_event (ptid
, &w
, options
);
3133 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3134 target_pid_to_str (step_over_bkpt
));
3135 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
3138 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3140 gdb_assert (target_options
& TARGET_WNOHANG
);
3144 debug_printf ("linux_wait_1 ret = null_ptid, "
3145 "TARGET_WAITKIND_IGNORE\n");
3149 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3156 debug_printf ("linux_wait_1 ret = null_ptid, "
3157 "TARGET_WAITKIND_NO_RESUMED\n");
3161 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3165 event_child
= get_thread_lwp (current_thread
);
3167 /* linux_wait_for_event only returns an exit status for the last
3168 child of a process. Report it. */
3169 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3173 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3174 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3178 debug_printf ("linux_wait_1 ret = %s, exited with "
3180 target_pid_to_str (ptid_of (current_thread
)),
3187 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3188 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3192 debug_printf ("linux_wait_1 ret = %s, terminated with "
3194 target_pid_to_str (ptid_of (current_thread
)),
3200 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3201 return filter_exit_event (event_child
, ourstatus
);
3203 return ptid_of (current_thread
);
3206 /* If step-over executes a breakpoint instruction, in the case of a
3207 hardware single step it means a gdb/gdbserver breakpoint had been
3208 planted on top of a permanent breakpoint, in the case of a software
3209 single step it may just mean that gdbserver hit the reinsert breakpoint.
3210 The PC has been adjusted by save_stop_reason to point at
3211 the breakpoint address.
3212 So in the case of the hardware single step advance the PC manually
3213 past the breakpoint and in the case of software single step advance only
3214 if it's not the reinsert_breakpoint we are hitting.
3215 This avoids that a program would keep trapping a permanent breakpoint
3217 if (!ptid_equal (step_over_bkpt
, null_ptid
)
3218 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3219 && (event_child
->stepping
3220 || !reinsert_breakpoint_inserted_here (event_child
->stop_pc
)))
3222 int increment_pc
= 0;
3223 int breakpoint_kind
= 0;
3224 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3227 the_target
->breakpoint_kind_from_current_state (&stop_pc
);
3228 the_target
->sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3232 debug_printf ("step-over for %s executed software breakpoint\n",
3233 target_pid_to_str (ptid_of (current_thread
)));
3236 if (increment_pc
!= 0)
3238 struct regcache
*regcache
3239 = get_thread_regcache (current_thread
, 1);
3241 event_child
->stop_pc
+= increment_pc
;
3242 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3244 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
3245 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3249 /* If this event was not handled before, and is not a SIGTRAP, we
3250 report it. SIGILL and SIGSEGV are also treated as traps in case
3251 a breakpoint is inserted at the current PC. If this target does
3252 not support internal breakpoints at all, we also report the
3253 SIGTRAP without further processing; it's of no concern to us. */
3255 = (supports_breakpoints ()
3256 && (WSTOPSIG (w
) == SIGTRAP
3257 || ((WSTOPSIG (w
) == SIGILL
3258 || WSTOPSIG (w
) == SIGSEGV
)
3259 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
3261 if (maybe_internal_trap
)
3263 /* Handle anything that requires bookkeeping before deciding to
3264 report the event or continue waiting. */
3266 /* First check if we can explain the SIGTRAP with an internal
3267 breakpoint, or if we should possibly report the event to GDB.
3268 Do this before anything that may remove or insert a
3270 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3272 /* We have a SIGTRAP, possibly a step-over dance has just
3273 finished. If so, tweak the state machine accordingly,
3274 reinsert breakpoints and delete any reinsert (software
3275 single-step) breakpoints. */
3276 step_over_finished
= finish_step_over (event_child
);
3278 /* Now invoke the callbacks of any internal breakpoints there. */
3279 check_breakpoints (event_child
->stop_pc
);
3281 /* Handle tracepoint data collecting. This may overflow the
3282 trace buffer, and cause a tracing stop, removing
3284 trace_event
= handle_tracepoints (event_child
);
3286 if (bp_explains_trap
)
3289 debug_printf ("Hit a gdbserver breakpoint.\n");
3294 /* We have some other signal, possibly a step-over dance was in
3295 progress, and it should be cancelled too. */
3296 step_over_finished
= finish_step_over (event_child
);
3299 /* We have all the data we need. Either report the event to GDB, or
3300 resume threads and keep waiting for more. */
3302 /* If we're collecting a fast tracepoint, finish the collection and
3303 move out of the jump pad before delivering a signal. See
3304 linux_stabilize_threads. */
3307 && WSTOPSIG (w
) != SIGTRAP
3308 && supports_fast_tracepoints ()
3309 && agent_loaded_p ())
3312 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3313 "to defer or adjust it.\n",
3314 WSTOPSIG (w
), lwpid_of (current_thread
));
3316 /* Allow debugging the jump pad itself. */
3317 if (current_thread
->last_resume_kind
!= resume_step
3318 && maybe_move_out_of_jump_pad (event_child
, &w
))
3320 enqueue_one_deferred_signal (event_child
, &w
);
3323 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3324 WSTOPSIG (w
), lwpid_of (current_thread
));
3326 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
3328 return ignore_event (ourstatus
);
3332 if (event_child
->collecting_fast_tracepoint
)
3335 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3336 "Check if we're already there.\n",
3337 lwpid_of (current_thread
),
3338 event_child
->collecting_fast_tracepoint
);
3342 event_child
->collecting_fast_tracepoint
3343 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3345 if (event_child
->collecting_fast_tracepoint
!= 1)
3347 /* No longer need this breakpoint. */
3348 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3351 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3352 "stopping all threads momentarily.\n");
3354 /* Other running threads could hit this breakpoint.
3355 We don't handle moribund locations like GDB does,
3356 instead we always pause all threads when removing
3357 breakpoints, so that any step-over or
3358 decr_pc_after_break adjustment is always taken
3359 care of while the breakpoint is still
3361 stop_all_lwps (1, event_child
);
3363 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3364 event_child
->exit_jump_pad_bkpt
= NULL
;
3366 unstop_all_lwps (1, event_child
);
3368 gdb_assert (event_child
->suspended
>= 0);
3372 if (event_child
->collecting_fast_tracepoint
== 0)
3375 debug_printf ("fast tracepoint finished "
3376 "collecting successfully.\n");
3378 /* We may have a deferred signal to report. */
3379 if (dequeue_one_deferred_signal (event_child
, &w
))
3382 debug_printf ("dequeued one signal.\n");
3387 debug_printf ("no deferred signals.\n");
3389 if (stabilizing_threads
)
3391 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3392 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3396 debug_printf ("linux_wait_1 ret = %s, stopped "
3397 "while stabilizing threads\n",
3398 target_pid_to_str (ptid_of (current_thread
)));
3402 return ptid_of (current_thread
);
3408 /* Check whether GDB would be interested in this event. */
3410 /* Check if GDB is interested in this syscall. */
3412 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3413 && !gdb_catch_this_syscall_p (event_child
))
3417 debug_printf ("Ignored syscall for LWP %ld.\n",
3418 lwpid_of (current_thread
));
3421 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3423 return ignore_event (ourstatus
);
3426 /* If GDB is not interested in this signal, don't stop other
3427 threads, and don't report it to GDB. Just resume the inferior
3428 right away. We do this for threading-related signals as well as
3429 any that GDB specifically requested we ignore. But never ignore
3430 SIGSTOP if we sent it ourselves, and do not ignore signals when
3431 stepping - they may require special handling to skip the signal
3432 handler. Also never ignore signals that could be caused by a
3435 && current_thread
->last_resume_kind
!= resume_step
3437 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3438 (current_process ()->priv
->thread_db
!= NULL
3439 && (WSTOPSIG (w
) == __SIGRTMIN
3440 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3443 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3444 && !(WSTOPSIG (w
) == SIGSTOP
3445 && current_thread
->last_resume_kind
== resume_stop
)
3446 && !linux_wstatus_maybe_breakpoint (w
))))
3448 siginfo_t info
, *info_p
;
3451 debug_printf ("Ignored signal %d for LWP %ld.\n",
3452 WSTOPSIG (w
), lwpid_of (current_thread
));
3454 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3455 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3460 if (step_over_finished
)
3462 /* We cancelled this thread's step-over above. We still
3463 need to unsuspend all other LWPs, and set them back
3464 running again while the signal handler runs. */
3465 unsuspend_all_lwps (event_child
);
3467 /* Enqueue the pending signal info so that proceed_all_lwps
3469 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3471 proceed_all_lwps ();
3475 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3476 WSTOPSIG (w
), info_p
);
3478 return ignore_event (ourstatus
);
3481 /* Note that all addresses are always "out of the step range" when
3482 there's no range to begin with. */
3483 in_step_range
= lwp_in_step_range (event_child
);
3485 /* If GDB wanted this thread to single step, and the thread is out
3486 of the step range, we always want to report the SIGTRAP, and let
3487 GDB handle it. Watchpoints should always be reported. So should
3488 signals we can't explain. A SIGTRAP we can't explain could be a
3489 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3490 do, we're be able to handle GDB breakpoints on top of internal
3491 breakpoints, by handling the internal breakpoint and still
3492 reporting the event to GDB. If we don't, we're out of luck, GDB
3493 won't see the breakpoint hit. If we see a single-step event but
3494 the thread should be continuing, don't pass the trap to gdb.
3495 That indicates that we had previously finished a single-step but
3496 left the single-step pending -- see
3497 complete_ongoing_step_over. */
3498 report_to_gdb
= (!maybe_internal_trap
3499 || (current_thread
->last_resume_kind
== resume_step
3501 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3503 && !bp_explains_trap
3505 && !step_over_finished
3506 && !(current_thread
->last_resume_kind
== resume_continue
3507 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3508 || (gdb_breakpoint_here (event_child
->stop_pc
)
3509 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3510 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3511 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3513 run_breakpoint_commands (event_child
->stop_pc
);
3515 /* We found no reason GDB would want us to stop. We either hit one
3516 of our own breakpoints, or finished an internal step GDB
3517 shouldn't know about. */
3522 if (bp_explains_trap
)
3523 debug_printf ("Hit a gdbserver breakpoint.\n");
3524 if (step_over_finished
)
3525 debug_printf ("Step-over finished.\n");
3527 debug_printf ("Tracepoint event.\n");
3528 if (lwp_in_step_range (event_child
))
3529 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3530 paddress (event_child
->stop_pc
),
3531 paddress (event_child
->step_range_start
),
3532 paddress (event_child
->step_range_end
));
3535 /* We're not reporting this breakpoint to GDB, so apply the
3536 decr_pc_after_break adjustment to the inferior's regcache
3539 if (the_low_target
.set_pc
!= NULL
)
3541 struct regcache
*regcache
3542 = get_thread_regcache (current_thread
, 1);
3543 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3546 /* We may have finished stepping over a breakpoint. If so,
3547 we've stopped and suspended all LWPs momentarily except the
3548 stepping one. This is where we resume them all again. We're
3549 going to keep waiting, so use proceed, which handles stepping
3550 over the next breakpoint. */
3552 debug_printf ("proceeding all threads.\n");
3554 if (step_over_finished
)
3555 unsuspend_all_lwps (event_child
);
3557 proceed_all_lwps ();
3558 return ignore_event (ourstatus
);
3563 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3567 str
= target_waitstatus_to_string (&event_child
->waitstatus
);
3568 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3569 lwpid_of (get_lwp_thread (event_child
)), str
);
3572 if (current_thread
->last_resume_kind
== resume_step
)
3574 if (event_child
->step_range_start
== event_child
->step_range_end
)
3575 debug_printf ("GDB wanted to single-step, reporting event.\n");
3576 else if (!lwp_in_step_range (event_child
))
3577 debug_printf ("Out of step range, reporting event.\n");
3579 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3580 debug_printf ("Stopped by watchpoint.\n");
3581 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3582 debug_printf ("Stopped by GDB breakpoint.\n");
3584 debug_printf ("Hit a non-gdbserver trap event.\n");
3587 /* Alright, we're going to report a stop. */
3589 if (!stabilizing_threads
)
3591 /* In all-stop, stop all threads. */
3593 stop_all_lwps (0, NULL
);
3595 /* If we're not waiting for a specific LWP, choose an event LWP
3596 from among those that have had events. Giving equal priority
3597 to all LWPs that have had events helps prevent
3599 if (ptid_equal (ptid
, minus_one_ptid
))
3601 event_child
->status_pending_p
= 1;
3602 event_child
->status_pending
= w
;
3604 select_event_lwp (&event_child
);
3606 /* current_thread and event_child must stay in sync. */
3607 current_thread
= get_lwp_thread (event_child
);
3609 event_child
->status_pending_p
= 0;
3610 w
= event_child
->status_pending
;
3613 if (step_over_finished
)
3617 /* If we were doing a step-over, all other threads but
3618 the stepping one had been paused in start_step_over,
3619 with their suspend counts incremented. We don't want
3620 to do a full unstop/unpause, because we're in
3621 all-stop mode (so we want threads stopped), but we
3622 still need to unsuspend the other threads, to
3623 decrement their `suspended' count back. */
3624 unsuspend_all_lwps (event_child
);
3628 /* If we just finished a step-over, then all threads had
3629 been momentarily paused. In all-stop, that's fine,
3630 we want threads stopped by now anyway. In non-stop,
3631 we need to re-resume threads that GDB wanted to be
3633 unstop_all_lwps (1, event_child
);
3637 /* Stabilize threads (move out of jump pads). */
3639 stabilize_threads ();
3643 /* If we just finished a step-over, then all threads had been
3644 momentarily paused. In all-stop, that's fine, we want
3645 threads stopped by now anyway. In non-stop, we need to
3646 re-resume threads that GDB wanted to be running. */
3647 if (step_over_finished
)
3648 unstop_all_lwps (1, event_child
);
3651 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3653 /* If the reported event is an exit, fork, vfork or exec, let
3655 *ourstatus
= event_child
->waitstatus
;
3656 /* Clear the event lwp's waitstatus since we handled it already. */
3657 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3660 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3662 /* Now that we've selected our final event LWP, un-adjust its PC if
3663 it was a software breakpoint, and the client doesn't know we can
3664 adjust the breakpoint ourselves. */
3665 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3666 && !swbreak_feature
)
3668 int decr_pc
= the_low_target
.decr_pc_after_break
;
3672 struct regcache
*regcache
3673 = get_thread_regcache (current_thread
, 1);
3674 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3678 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3682 get_syscall_trapinfo (event_child
,
3683 &ourstatus
->value
.syscall_number
, &sysret
);
3684 ourstatus
->kind
= event_child
->syscall_state
;
3686 else if (current_thread
->last_resume_kind
== resume_stop
3687 && WSTOPSIG (w
) == SIGSTOP
)
3689 /* A thread that has been requested to stop by GDB with vCont;t,
3690 and it stopped cleanly, so report as SIG0. The use of
3691 SIGSTOP is an implementation detail. */
3692 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3694 else if (current_thread
->last_resume_kind
== resume_stop
3695 && WSTOPSIG (w
) != SIGSTOP
)
3697 /* A thread that has been requested to stop by GDB with vCont;t,
3698 but, it stopped for other reasons. */
3699 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3701 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3703 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3706 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
3710 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3711 target_pid_to_str (ptid_of (current_thread
)),
3712 ourstatus
->kind
, ourstatus
->value
.sig
);
3716 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3717 return filter_exit_event (event_child
, ourstatus
);
3719 return ptid_of (current_thread
);
3722 /* Get rid of any pending event in the pipe. */
3724 async_file_flush (void)
3730 ret
= read (linux_event_pipe
[0], &buf
, 1);
3731 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3734 /* Put something in the pipe, so the event loop wakes up. */
3736 async_file_mark (void)
3740 async_file_flush ();
3743 ret
= write (linux_event_pipe
[1], "+", 1);
3744 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3746 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3747 be awakened anyway. */
3751 linux_wait (ptid_t ptid
,
3752 struct target_waitstatus
*ourstatus
, int target_options
)
3756 /* Flush the async file first. */
3757 if (target_is_async_p ())
3758 async_file_flush ();
3762 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3764 while ((target_options
& TARGET_WNOHANG
) == 0
3765 && ptid_equal (event_ptid
, null_ptid
)
3766 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3768 /* If at least one stop was reported, there may be more. A single
3769 SIGCHLD can signal more than one child stop. */
3770 if (target_is_async_p ()
3771 && (target_options
& TARGET_WNOHANG
) != 0
3772 && !ptid_equal (event_ptid
, null_ptid
))
3778 /* Send a signal to an LWP. */
3781 kill_lwp (unsigned long lwpid
, int signo
)
3786 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3787 if (errno
== ENOSYS
)
3789 /* If tkill fails, then we are not using nptl threads, a
3790 configuration we no longer support. */
3791 perror_with_name (("tkill"));
3797 linux_stop_lwp (struct lwp_info
*lwp
)
3803 send_sigstop (struct lwp_info
*lwp
)
3807 pid
= lwpid_of (get_lwp_thread (lwp
));
3809 /* If we already have a pending stop signal for this process, don't
3811 if (lwp
->stop_expected
)
3814 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3820 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3822 lwp
->stop_expected
= 1;
3823 kill_lwp (pid
, SIGSTOP
);
3827 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
3829 struct thread_info
*thread
= (struct thread_info
*) entry
;
3830 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3832 /* Ignore EXCEPT. */
3843 /* Increment the suspend count of an LWP, and stop it, if not stopped
3846 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
3849 struct thread_info
*thread
= (struct thread_info
*) entry
;
3850 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3852 /* Ignore EXCEPT. */
3856 lwp_suspended_inc (lwp
);
3858 return send_sigstop_callback (entry
, except
);
3862 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3864 /* Store the exit status for later. */
3865 lwp
->status_pending_p
= 1;
3866 lwp
->status_pending
= wstat
;
3868 /* Store in waitstatus as well, as there's nothing else to process
3870 if (WIFEXITED (wstat
))
3872 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3873 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3875 else if (WIFSIGNALED (wstat
))
3877 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3878 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3881 /* Prevent trying to stop it. */
3884 /* No further stops are expected from a dead lwp. */
3885 lwp
->stop_expected
= 0;
3888 /* Return true if LWP has exited already, and has a pending exit event
3889 to report to GDB. */
3892 lwp_is_marked_dead (struct lwp_info
*lwp
)
3894 return (lwp
->status_pending_p
3895 && (WIFEXITED (lwp
->status_pending
)
3896 || WIFSIGNALED (lwp
->status_pending
)));
3899 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3902 wait_for_sigstop (void)
3904 struct thread_info
*saved_thread
;
3909 saved_thread
= current_thread
;
3910 if (saved_thread
!= NULL
)
3911 saved_tid
= saved_thread
->entry
.id
;
3913 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3916 debug_printf ("wait_for_sigstop: pulling events\n");
3918 /* Passing NULL_PTID as filter indicates we want all events to be
3919 left pending. Eventually this returns when there are no
3920 unwaited-for children left. */
3921 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
3923 gdb_assert (ret
== -1);
3925 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
3926 current_thread
= saved_thread
;
3930 debug_printf ("Previously current thread died.\n");
3932 /* We can't change the current inferior behind GDB's back,
3933 otherwise, a subsequent command may apply to the wrong
3935 current_thread
= NULL
;
3939 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3940 move it out, because we need to report the stop event to GDB. For
3941 example, if the user puts a breakpoint in the jump pad, it's
3942 because she wants to debug it. */
3945 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3947 struct thread_info
*thread
= (struct thread_info
*) entry
;
3948 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3950 if (lwp
->suspended
!= 0)
3952 internal_error (__FILE__
, __LINE__
,
3953 "LWP %ld is suspended, suspended=%d\n",
3954 lwpid_of (thread
), lwp
->suspended
);
3956 gdb_assert (lwp
->stopped
);
3958 /* Allow debugging the jump pad, gdb_collect, etc.. */
3959 return (supports_fast_tracepoints ()
3960 && agent_loaded_p ()
3961 && (gdb_breakpoint_here (lwp
->stop_pc
)
3962 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3963 || thread
->last_resume_kind
== resume_step
)
3964 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3968 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3970 struct thread_info
*thread
= (struct thread_info
*) entry
;
3971 struct thread_info
*saved_thread
;
3972 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3975 if (lwp
->suspended
!= 0)
3977 internal_error (__FILE__
, __LINE__
,
3978 "LWP %ld is suspended, suspended=%d\n",
3979 lwpid_of (thread
), lwp
->suspended
);
3981 gdb_assert (lwp
->stopped
);
3983 /* For gdb_breakpoint_here. */
3984 saved_thread
= current_thread
;
3985 current_thread
= thread
;
3987 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3989 /* Allow debugging the jump pad, gdb_collect, etc. */
3990 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3991 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3992 && thread
->last_resume_kind
!= resume_step
3993 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3996 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
4001 lwp
->status_pending_p
= 0;
4002 enqueue_one_deferred_signal (lwp
, wstat
);
4005 debug_printf ("Signal %d for LWP %ld deferred "
4007 WSTOPSIG (*wstat
), lwpid_of (thread
));
4010 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
4013 lwp_suspended_inc (lwp
);
4015 current_thread
= saved_thread
;
4019 lwp_running (struct inferior_list_entry
*entry
, void *data
)
4021 struct thread_info
*thread
= (struct thread_info
*) entry
;
4022 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4024 if (lwp_is_marked_dead (lwp
))
4031 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
4032 If SUSPEND, then also increase the suspend count of every LWP,
4036 stop_all_lwps (int suspend
, struct lwp_info
*except
)
4038 /* Should not be called recursively. */
4039 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
4044 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4045 suspend
? "stop-and-suspend" : "stop",
4047 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
4051 stopping_threads
= (suspend
4052 ? STOPPING_AND_SUSPENDING_THREADS
4053 : STOPPING_THREADS
);
4056 find_inferior (&all_threads
, suspend_and_send_sigstop_callback
, except
);
4058 find_inferior (&all_threads
, send_sigstop_callback
, except
);
4059 wait_for_sigstop ();
4060 stopping_threads
= NOT_STOPPING_THREADS
;
4064 debug_printf ("stop_all_lwps done, setting stopping_threads "
4065 "back to !stopping\n");
4070 /* Enqueue one signal in the chain of signals which need to be
4071 delivered to this process on next resume. */
4074 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
4076 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
4078 p_sig
->prev
= lwp
->pending_signals
;
4079 p_sig
->signal
= signal
;
4081 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4083 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
4084 lwp
->pending_signals
= p_sig
;
4087 /* Install breakpoints for software single stepping. */
4090 install_software_single_step_breakpoints (struct lwp_info
*lwp
)
4094 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4095 VEC (CORE_ADDR
) *next_pcs
= NULL
;
4096 struct cleanup
*old_chain
= make_cleanup (VEC_cleanup (CORE_ADDR
), &next_pcs
);
4098 next_pcs
= (*the_low_target
.get_next_pcs
) (regcache
);
4100 for (i
= 0; VEC_iterate (CORE_ADDR
, next_pcs
, i
, pc
); ++i
)
4101 set_reinsert_breakpoint (pc
);
4103 do_cleanups (old_chain
);
4106 /* Single step via hardware or software single step.
4107 Return 1 if hardware single stepping, 0 if software single stepping
4108 or can't single step. */
4111 single_step (struct lwp_info
* lwp
)
4115 if (can_hardware_single_step ())
4119 else if (can_software_single_step ())
4121 install_software_single_step_breakpoints (lwp
);
4127 debug_printf ("stepping is not implemented on this target");
4133 /* The signal can be delivered to the inferior if we are not trying to
4134 finish a fast tracepoint collect. Since signal can be delivered in
4135 the step-over, the program may go to signal handler and trap again
4136 after return from the signal handler. We can live with the spurious
4140 lwp_signal_can_be_delivered (struct lwp_info
*lwp
)
4142 return !lwp
->collecting_fast_tracepoint
;
4145 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
4146 SIGNAL is nonzero, give it that signal. */
4149 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
4150 int step
, int signal
, siginfo_t
*info
)
4152 struct thread_info
*thread
= get_lwp_thread (lwp
);
4153 struct thread_info
*saved_thread
;
4154 int fast_tp_collecting
;
4156 struct process_info
*proc
= get_thread_process (thread
);
4158 /* Note that target description may not be initialised
4159 (proc->tdesc == NULL) at this point because the program hasn't
4160 stopped at the first instruction yet. It means GDBserver skips
4161 the extra traps from the wrapper program (see option --wrapper).
4162 Code in this function that requires register access should be
4163 guarded by proc->tdesc == NULL or something else. */
4165 if (lwp
->stopped
== 0)
4168 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
4170 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
4172 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
4174 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4175 user used the "jump" command, or "set $pc = foo"). */
4176 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
4178 /* Collecting 'while-stepping' actions doesn't make sense
4180 release_while_stepping_state_list (thread
);
4183 /* If we have pending signals or status, and a new signal, enqueue the
4184 signal. Also enqueue the signal if it can't be delivered to the
4185 inferior right now. */
4187 && (lwp
->status_pending_p
4188 || lwp
->pending_signals
!= NULL
4189 || !lwp_signal_can_be_delivered (lwp
)))
4191 enqueue_pending_signal (lwp
, signal
, info
);
4193 /* Postpone any pending signal. It was enqueued above. */
4197 if (lwp
->status_pending_p
)
4200 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4201 " has pending status\n",
4202 lwpid_of (thread
), step
? "step" : "continue",
4203 lwp
->stop_expected
? "expected" : "not expected");
4207 saved_thread
= current_thread
;
4208 current_thread
= thread
;
4210 /* This bit needs some thinking about. If we get a signal that
4211 we must report while a single-step reinsert is still pending,
4212 we often end up resuming the thread. It might be better to
4213 (ew) allow a stack of pending events; then we could be sure that
4214 the reinsert happened right away and not lose any signals.
4216 Making this stack would also shrink the window in which breakpoints are
4217 uninserted (see comment in linux_wait_for_lwp) but not enough for
4218 complete correctness, so it won't solve that problem. It may be
4219 worthwhile just to solve this one, however. */
4220 if (lwp
->bp_reinsert
!= 0)
4223 debug_printf (" pending reinsert at 0x%s\n",
4224 paddress (lwp
->bp_reinsert
));
4226 if (can_hardware_single_step ())
4228 if (fast_tp_collecting
== 0)
4231 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
4233 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
4238 step
= maybe_hw_step (thread
);
4242 /* If the thread isn't doing step-over, there shouldn't be any
4243 reinsert breakpoints. */
4244 gdb_assert (!has_reinsert_breakpoints (proc
));
4247 if (fast_tp_collecting
== 1)
4250 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4251 " (exit-jump-pad-bkpt)\n",
4254 else if (fast_tp_collecting
== 2)
4257 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4258 " single-stepping\n",
4261 if (can_hardware_single_step ())
4265 internal_error (__FILE__
, __LINE__
,
4266 "moving out of jump pad single-stepping"
4267 " not implemented on this target");
4271 /* If we have while-stepping actions in this thread set it stepping.
4272 If we have a signal to deliver, it may or may not be set to
4273 SIG_IGN, we don't know. Assume so, and allow collecting
4274 while-stepping into a signal handler. A possible smart thing to
4275 do would be to set an internal breakpoint at the signal return
4276 address, continue, and carry on catching this while-stepping
4277 action only when that breakpoint is hit. A future
4279 if (thread
->while_stepping
!= NULL
)
4282 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4285 step
= single_step (lwp
);
4288 if (proc
->tdesc
!= NULL
&& the_low_target
.get_pc
!= NULL
)
4290 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4292 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
4296 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4297 (long) lwp
->stop_pc
);
4301 /* If we have pending signals, consume one if it can be delivered to
4303 if (lwp
->pending_signals
!= NULL
&& lwp_signal_can_be_delivered (lwp
))
4305 struct pending_signals
**p_sig
;
4307 p_sig
= &lwp
->pending_signals
;
4308 while ((*p_sig
)->prev
!= NULL
)
4309 p_sig
= &(*p_sig
)->prev
;
4311 signal
= (*p_sig
)->signal
;
4312 if ((*p_sig
)->info
.si_signo
!= 0)
4313 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4321 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4322 lwpid_of (thread
), step
? "step" : "continue", signal
,
4323 lwp
->stop_expected
? "expected" : "not expected");
4325 if (the_low_target
.prepare_to_resume
!= NULL
)
4326 the_low_target
.prepare_to_resume (lwp
);
4328 regcache_invalidate_thread (thread
);
4330 lwp
->stepping
= step
;
4332 ptrace_request
= PTRACE_SINGLESTEP
;
4333 else if (gdb_catching_syscalls_p (lwp
))
4334 ptrace_request
= PTRACE_SYSCALL
;
4336 ptrace_request
= PTRACE_CONT
;
4337 ptrace (ptrace_request
,
4339 (PTRACE_TYPE_ARG3
) 0,
4340 /* Coerce to a uintptr_t first to avoid potential gcc warning
4341 of coercing an 8 byte integer to a 4 byte pointer. */
4342 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4344 current_thread
= saved_thread
;
4346 perror_with_name ("resuming thread");
4348 /* Successfully resumed. Clear state that no longer makes sense,
4349 and mark the LWP as running. Must not do this before resuming
4350 otherwise if that fails other code will be confused. E.g., we'd
4351 later try to stop the LWP and hang forever waiting for a stop
4352 status. Note that we must not throw after this is cleared,
4353 otherwise handle_zombie_lwp_error would get confused. */
4355 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4358 /* Called when we try to resume a stopped LWP and that errors out. If
4359 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4360 or about to become), discard the error, clear any pending status
4361 the LWP may have, and return true (we'll collect the exit status
4362 soon enough). Otherwise, return false. */
4365 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4367 struct thread_info
*thread
= get_lwp_thread (lp
);
4369 /* If we get an error after resuming the LWP successfully, we'd
4370 confuse !T state for the LWP being gone. */
4371 gdb_assert (lp
->stopped
);
4373 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4374 because even if ptrace failed with ESRCH, the tracee may be "not
4375 yet fully dead", but already refusing ptrace requests. In that
4376 case the tracee has 'R (Running)' state for a little bit
4377 (observed in Linux 3.18). See also the note on ESRCH in the
4378 ptrace(2) man page. Instead, check whether the LWP has any state
4379 other than ptrace-stopped. */
4381 /* Don't assume anything if /proc/PID/status can't be read. */
4382 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4384 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4385 lp
->status_pending_p
= 0;
4391 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4392 disappears while we try to resume it. */
4395 linux_resume_one_lwp (struct lwp_info
*lwp
,
4396 int step
, int signal
, siginfo_t
*info
)
4400 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
4402 CATCH (ex
, RETURN_MASK_ERROR
)
4404 if (!check_ptrace_stopped_lwp_gone (lwp
))
4405 throw_exception (ex
);
4410 struct thread_resume_array
4412 struct thread_resume
*resume
;
4416 /* This function is called once per thread via find_inferior.
4417 ARG is a pointer to a thread_resume_array struct.
4418 We look up the thread specified by ENTRY in ARG, and mark the thread
4419 with a pointer to the appropriate resume request.
4421 This algorithm is O(threads * resume elements), but resume elements
4422 is small (and will remain small at least until GDB supports thread
4426 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
4428 struct thread_info
*thread
= (struct thread_info
*) entry
;
4429 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4431 struct thread_resume_array
*r
;
4433 r
= (struct thread_resume_array
*) arg
;
4435 for (ndx
= 0; ndx
< r
->n
; ndx
++)
4437 ptid_t ptid
= r
->resume
[ndx
].thread
;
4438 if (ptid_equal (ptid
, minus_one_ptid
)
4439 || ptid_equal (ptid
, entry
->id
)
4440 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4442 || (ptid_get_pid (ptid
) == pid_of (thread
)
4443 && (ptid_is_pid (ptid
)
4444 || ptid_get_lwp (ptid
) == -1)))
4446 if (r
->resume
[ndx
].kind
== resume_stop
4447 && thread
->last_resume_kind
== resume_stop
)
4450 debug_printf ("already %s LWP %ld at GDB's request\n",
4451 (thread
->last_status
.kind
4452 == TARGET_WAITKIND_STOPPED
)
4460 lwp
->resume
= &r
->resume
[ndx
];
4461 thread
->last_resume_kind
= lwp
->resume
->kind
;
4463 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4464 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4466 /* If we had a deferred signal to report, dequeue one now.
4467 This can happen if LWP gets more than one signal while
4468 trying to get out of a jump pad. */
4470 && !lwp
->status_pending_p
4471 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4473 lwp
->status_pending_p
= 1;
4476 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4477 "leaving status pending.\n",
4478 WSTOPSIG (lwp
->status_pending
),
4486 /* No resume action for this thread. */
4492 /* find_inferior callback for linux_resume.
4493 Set *FLAG_P if this lwp has an interesting status pending. */
4496 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
4498 struct thread_info
*thread
= (struct thread_info
*) entry
;
4499 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4501 /* LWPs which will not be resumed are not interesting, because
4502 we might not wait for them next time through linux_wait. */
4503 if (lwp
->resume
== NULL
)
4506 if (thread_still_has_status_pending_p (thread
))
4507 * (int *) flag_p
= 1;
4512 /* Return 1 if this lwp that GDB wants running is stopped at an
4513 internal breakpoint that we need to step over. It assumes that any
4514 required STOP_PC adjustment has already been propagated to the
4515 inferior's regcache. */
4518 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
4520 struct thread_info
*thread
= (struct thread_info
*) entry
;
4521 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4522 struct thread_info
*saved_thread
;
4524 struct process_info
*proc
= get_thread_process (thread
);
4526 /* GDBserver is skipping the extra traps from the wrapper program,
4527 don't have to do step over. */
4528 if (proc
->tdesc
== NULL
)
4531 /* LWPs which will not be resumed are not interesting, because we
4532 might not wait for them next time through linux_wait. */
4537 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4542 if (thread
->last_resume_kind
== resume_stop
)
4545 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4551 gdb_assert (lwp
->suspended
>= 0);
4556 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4561 if (lwp
->status_pending_p
)
4564 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4570 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4574 /* If the PC has changed since we stopped, then don't do anything,
4575 and let the breakpoint/tracepoint be hit. This happens if, for
4576 instance, GDB handled the decr_pc_after_break subtraction itself,
4577 GDB is OOL stepping this thread, or the user has issued a "jump"
4578 command, or poked thread's registers herself. */
4579 if (pc
!= lwp
->stop_pc
)
4582 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4583 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4585 paddress (lwp
->stop_pc
), paddress (pc
));
4589 /* On software single step target, resume the inferior with signal
4590 rather than stepping over. */
4591 if (can_software_single_step ()
4592 && lwp
->pending_signals
!= NULL
4593 && lwp_signal_can_be_delivered (lwp
))
4596 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4603 saved_thread
= current_thread
;
4604 current_thread
= thread
;
4606 /* We can only step over breakpoints we know about. */
4607 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4609 /* Don't step over a breakpoint that GDB expects to hit
4610 though. If the condition is being evaluated on the target's side
4611 and it evaluate to false, step over this breakpoint as well. */
4612 if (gdb_breakpoint_here (pc
)
4613 && gdb_condition_true_at_breakpoint (pc
)
4614 && gdb_no_commands_at_breakpoint (pc
))
4617 debug_printf ("Need step over [LWP %ld]? yes, but found"
4618 " GDB breakpoint at 0x%s; skipping step over\n",
4619 lwpid_of (thread
), paddress (pc
));
4621 current_thread
= saved_thread
;
4627 debug_printf ("Need step over [LWP %ld]? yes, "
4628 "found breakpoint at 0x%s\n",
4629 lwpid_of (thread
), paddress (pc
));
4631 /* We've found an lwp that needs stepping over --- return 1 so
4632 that find_inferior stops looking. */
4633 current_thread
= saved_thread
;
4639 current_thread
= saved_thread
;
4642 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4644 lwpid_of (thread
), paddress (pc
));
4649 /* Start a step-over operation on LWP. When LWP stopped at a
4650 breakpoint, to make progress, we need to remove the breakpoint out
4651 of the way. If we let other threads run while we do that, they may
4652 pass by the breakpoint location and miss hitting it. To avoid
4653 that, a step-over momentarily stops all threads while LWP is
4654 single-stepped by either hardware or software while the breakpoint
4655 is temporarily uninserted from the inferior. When the single-step
4656 finishes, we reinsert the breakpoint, and let all threads that are
4657 supposed to be running, run again. */
4660 start_step_over (struct lwp_info
*lwp
)
4662 struct thread_info
*thread
= get_lwp_thread (lwp
);
4663 struct thread_info
*saved_thread
;
4668 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4671 stop_all_lwps (1, lwp
);
4673 if (lwp
->suspended
!= 0)
4675 internal_error (__FILE__
, __LINE__
,
4676 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4681 debug_printf ("Done stopping all threads for step-over.\n");
4683 /* Note, we should always reach here with an already adjusted PC,
4684 either by GDB (if we're resuming due to GDB's request), or by our
4685 caller, if we just finished handling an internal breakpoint GDB
4686 shouldn't care about. */
4689 saved_thread
= current_thread
;
4690 current_thread
= thread
;
4692 lwp
->bp_reinsert
= pc
;
4693 uninsert_breakpoints_at (pc
);
4694 uninsert_fast_tracepoint_jumps_at (pc
);
4696 step
= single_step (lwp
);
4698 current_thread
= saved_thread
;
4700 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4702 /* Require next event from this LWP. */
4703 step_over_bkpt
= thread
->entry
.id
;
4707 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4708 start_step_over, if still there, and delete any reinsert
4709 breakpoints we've set, on non hardware single-step targets. */
4712 finish_step_over (struct lwp_info
*lwp
)
4714 if (lwp
->bp_reinsert
!= 0)
4716 struct thread_info
*saved_thread
= current_thread
;
4719 debug_printf ("Finished step over.\n");
4721 current_thread
= get_lwp_thread (lwp
);
4723 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4724 may be no breakpoint to reinsert there by now. */
4725 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4726 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4728 lwp
->bp_reinsert
= 0;
4730 /* Delete any software-single-step reinsert breakpoints. No
4731 longer needed. We don't have to worry about other threads
4732 hitting this trap, and later not being able to explain it,
4733 because we were stepping over a breakpoint, and we hold all
4734 threads but LWP stopped while doing that. */
4735 if (!can_hardware_single_step ())
4737 gdb_assert (has_reinsert_breakpoints (current_process ()));
4738 delete_reinsert_breakpoints ();
4741 step_over_bkpt
= null_ptid
;
4742 current_thread
= saved_thread
;
4749 /* If there's a step over in progress, wait until all threads stop
4750 (that is, until the stepping thread finishes its step), and
4751 unsuspend all lwps. The stepping thread ends with its status
4752 pending, which is processed later when we get back to processing
4756 complete_ongoing_step_over (void)
4758 if (!ptid_equal (step_over_bkpt
, null_ptid
))
4760 struct lwp_info
*lwp
;
4765 debug_printf ("detach: step over in progress, finish it first\n");
4767 /* Passing NULL_PTID as filter indicates we want all events to
4768 be left pending. Eventually this returns when there are no
4769 unwaited-for children left. */
4770 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4772 gdb_assert (ret
== -1);
4774 lwp
= find_lwp_pid (step_over_bkpt
);
4776 finish_step_over (lwp
);
4777 step_over_bkpt
= null_ptid
;
4778 unsuspend_all_lwps (lwp
);
4782 /* This function is called once per thread. We check the thread's resume
4783 request, which will tell us whether to resume, step, or leave the thread
4784 stopped; and what signal, if any, it should be sent.
4786 For threads which we aren't explicitly told otherwise, we preserve
4787 the stepping flag; this is used for stepping over gdbserver-placed
4790 If pending_flags was set in any thread, we queue any needed
4791 signals, since we won't actually resume. We already have a pending
4792 event to report, so we don't need to preserve any step requests;
4793 they should be re-issued if necessary. */
4796 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
4798 struct thread_info
*thread
= (struct thread_info
*) entry
;
4799 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4801 int leave_all_stopped
= * (int *) arg
;
4804 if (lwp
->resume
== NULL
)
4807 if (lwp
->resume
->kind
== resume_stop
)
4810 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4815 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4817 /* Stop the thread, and wait for the event asynchronously,
4818 through the event loop. */
4824 debug_printf ("already stopped LWP %ld\n",
4827 /* The LWP may have been stopped in an internal event that
4828 was not meant to be notified back to GDB (e.g., gdbserver
4829 breakpoint), so we should be reporting a stop event in
4832 /* If the thread already has a pending SIGSTOP, this is a
4833 no-op. Otherwise, something later will presumably resume
4834 the thread and this will cause it to cancel any pending
4835 operation, due to last_resume_kind == resume_stop. If
4836 the thread already has a pending status to report, we
4837 will still report it the next time we wait - see
4838 status_pending_p_callback. */
4840 /* If we already have a pending signal to report, then
4841 there's no need to queue a SIGSTOP, as this means we're
4842 midway through moving the LWP out of the jumppad, and we
4843 will report the pending signal as soon as that is
4845 if (lwp
->pending_signals_to_report
== NULL
)
4849 /* For stop requests, we're done. */
4851 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4855 /* If this thread which is about to be resumed has a pending status,
4856 then don't resume it - we can just report the pending status.
4857 Likewise if it is suspended, because e.g., another thread is
4858 stepping past a breakpoint. Make sure to queue any signals that
4859 would otherwise be sent. In all-stop mode, we do this decision
4860 based on if *any* thread has a pending status. If there's a
4861 thread that needs the step-over-breakpoint dance, then don't
4862 resume any other thread but that particular one. */
4863 leave_pending
= (lwp
->suspended
4864 || lwp
->status_pending_p
4865 || leave_all_stopped
);
4870 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4872 step
= (lwp
->resume
->kind
== resume_step
);
4873 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
4878 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4880 /* If we have a new signal, enqueue the signal. */
4881 if (lwp
->resume
->sig
!= 0)
4883 struct pending_signals
*p_sig
= XCNEW (struct pending_signals
);
4885 p_sig
->prev
= lwp
->pending_signals
;
4886 p_sig
->signal
= lwp
->resume
->sig
;
4888 /* If this is the same signal we were previously stopped by,
4889 make sure to queue its siginfo. We can ignore the return
4890 value of ptrace; if it fails, we'll skip
4891 PTRACE_SETSIGINFO. */
4892 if (WIFSTOPPED (lwp
->last_status
)
4893 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
4894 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4897 lwp
->pending_signals
= p_sig
;
4901 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4907 linux_resume (struct thread_resume
*resume_info
, size_t n
)
4909 struct thread_resume_array array
= { resume_info
, n
};
4910 struct thread_info
*need_step_over
= NULL
;
4912 int leave_all_stopped
;
4917 debug_printf ("linux_resume:\n");
4920 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
4922 /* If there is a thread which would otherwise be resumed, which has
4923 a pending status, then don't resume any threads - we can just
4924 report the pending status. Make sure to queue any signals that
4925 would otherwise be sent. In non-stop mode, we'll apply this
4926 logic to each thread individually. We consume all pending events
4927 before considering to start a step-over (in all-stop). */
4930 find_inferior (&all_threads
, resume_status_pending_p
, &any_pending
);
4932 /* If there is a thread which would otherwise be resumed, which is
4933 stopped at a breakpoint that needs stepping over, then don't
4934 resume any threads - have it step over the breakpoint with all
4935 other threads stopped, then resume all threads again. Make sure
4936 to queue any signals that would otherwise be delivered or
4938 if (!any_pending
&& supports_breakpoints ())
4940 = (struct thread_info
*) find_inferior (&all_threads
,
4941 need_step_over_p
, NULL
);
4943 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4947 if (need_step_over
!= NULL
)
4948 debug_printf ("Not resuming all, need step over\n");
4949 else if (any_pending
)
4950 debug_printf ("Not resuming, all-stop and found "
4951 "an LWP with pending status\n");
4953 debug_printf ("Resuming, no pending status or step over needed\n");
4956 /* Even if we're leaving threads stopped, queue all signals we'd
4957 otherwise deliver. */
4958 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
4961 start_step_over (get_thread_lwp (need_step_over
));
4965 debug_printf ("linux_resume done\n");
4969 /* We may have events that were pending that can/should be sent to
4970 the client now. Trigger a linux_wait call. */
4971 if (target_is_async_p ())
4975 /* This function is called once per thread. We check the thread's
4976 last resume request, which will tell us whether to resume, step, or
4977 leave the thread stopped. Any signal the client requested to be
4978 delivered has already been enqueued at this point.
4980 If any thread that GDB wants running is stopped at an internal
4981 breakpoint that needs stepping over, we start a step-over operation
4982 on that particular thread, and leave all others stopped. */
4985 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4987 struct thread_info
*thread
= (struct thread_info
*) entry
;
4988 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4995 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
5000 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
5004 if (thread
->last_resume_kind
== resume_stop
5005 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
5008 debug_printf (" client wants LWP to remain %ld stopped\n",
5013 if (lwp
->status_pending_p
)
5016 debug_printf (" LWP %ld has pending status, leaving stopped\n",
5021 gdb_assert (lwp
->suspended
>= 0);
5026 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
5030 if (thread
->last_resume_kind
== resume_stop
5031 && lwp
->pending_signals_to_report
== NULL
5032 && lwp
->collecting_fast_tracepoint
== 0)
5034 /* We haven't reported this LWP as stopped yet (otherwise, the
5035 last_status.kind check above would catch it, and we wouldn't
5036 reach here. This LWP may have been momentarily paused by a
5037 stop_all_lwps call while handling for example, another LWP's
5038 step-over. In that case, the pending expected SIGSTOP signal
5039 that was queued at vCont;t handling time will have already
5040 been consumed by wait_for_sigstop, and so we need to requeue
5041 another one here. Note that if the LWP already has a SIGSTOP
5042 pending, this is a no-op. */
5045 debug_printf ("Client wants LWP %ld to stop. "
5046 "Making sure it has a SIGSTOP pending\n",
5052 if (thread
->last_resume_kind
== resume_step
)
5055 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5059 else if (lwp
->bp_reinsert
!= 0)
5062 debug_printf (" stepping LWP %ld, reinsert set\n",
5065 step
= maybe_hw_step (thread
);
5070 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
5075 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
5077 struct thread_info
*thread
= (struct thread_info
*) entry
;
5078 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5083 lwp_suspended_decr (lwp
);
5085 return proceed_one_lwp (entry
, except
);
5088 /* When we finish a step-over, set threads running again. If there's
5089 another thread that may need a step-over, now's the time to start
5090 it. Eventually, we'll move all threads past their breakpoints. */
5093 proceed_all_lwps (void)
5095 struct thread_info
*need_step_over
;
5097 /* If there is a thread which would otherwise be resumed, which is
5098 stopped at a breakpoint that needs stepping over, then don't
5099 resume any threads - have it step over the breakpoint with all
5100 other threads stopped, then resume all threads again. */
5102 if (supports_breakpoints ())
5105 = (struct thread_info
*) find_inferior (&all_threads
,
5106 need_step_over_p
, NULL
);
5108 if (need_step_over
!= NULL
)
5111 debug_printf ("proceed_all_lwps: found "
5112 "thread %ld needing a step-over\n",
5113 lwpid_of (need_step_over
));
5115 start_step_over (get_thread_lwp (need_step_over
));
5121 debug_printf ("Proceeding, no step-over needed\n");
5123 find_inferior (&all_threads
, proceed_one_lwp
, NULL
);
5126 /* Stopped LWPs that the client wanted to be running, that don't have
5127 pending statuses, are set to run again, except for EXCEPT, if not
5128 NULL. This undoes a stop_all_lwps call. */
5131 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
5137 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5138 lwpid_of (get_lwp_thread (except
)));
5140 debug_printf ("unstopping all lwps\n");
5144 find_inferior (&all_threads
, unsuspend_and_proceed_one_lwp
, except
);
5146 find_inferior (&all_threads
, proceed_one_lwp
, except
);
5150 debug_printf ("unstop_all_lwps done\n");
5156 #ifdef HAVE_LINUX_REGSETS
5158 #define use_linux_regsets 1
5160 /* Returns true if REGSET has been disabled. */
5163 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
5165 return (info
->disabled_regsets
!= NULL
5166 && info
->disabled_regsets
[regset
- info
->regsets
]);
5169 /* Disable REGSET. */
5172 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5176 dr_offset
= regset
- info
->regsets
;
5177 if (info
->disabled_regsets
== NULL
)
5178 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5179 info
->disabled_regsets
[dr_offset
] = 1;
5183 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5184 struct regcache
*regcache
)
5186 struct regset_info
*regset
;
5187 int saw_general_regs
= 0;
5191 pid
= lwpid_of (current_thread
);
5192 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5197 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5200 buf
= xmalloc (regset
->size
);
5202 nt_type
= regset
->nt_type
;
5206 iov
.iov_len
= regset
->size
;
5207 data
= (void *) &iov
;
5213 res
= ptrace (regset
->get_request
, pid
,
5214 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5216 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5222 /* If we get EIO on a regset, do not try it again for
5223 this process mode. */
5224 disable_regset (regsets_info
, regset
);
5226 else if (errno
== ENODATA
)
5228 /* ENODATA may be returned if the regset is currently
5229 not "active". This can happen in normal operation,
5230 so suppress the warning in this case. */
5235 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5242 if (regset
->type
== GENERAL_REGS
)
5243 saw_general_regs
= 1;
5244 regset
->store_function (regcache
, buf
);
5248 if (saw_general_regs
)
5255 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5256 struct regcache
*regcache
)
5258 struct regset_info
*regset
;
5259 int saw_general_regs
= 0;
5263 pid
= lwpid_of (current_thread
);
5264 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5269 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5270 || regset
->fill_function
== NULL
)
5273 buf
= xmalloc (regset
->size
);
5275 /* First fill the buffer with the current register set contents,
5276 in case there are any items in the kernel's regset that are
5277 not in gdbserver's regcache. */
5279 nt_type
= regset
->nt_type
;
5283 iov
.iov_len
= regset
->size
;
5284 data
= (void *) &iov
;
5290 res
= ptrace (regset
->get_request
, pid
,
5291 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5293 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5298 /* Then overlay our cached registers on that. */
5299 regset
->fill_function (regcache
, buf
);
5301 /* Only now do we write the register set. */
5303 res
= ptrace (regset
->set_request
, pid
,
5304 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5306 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5314 /* If we get EIO on a regset, do not try it again for
5315 this process mode. */
5316 disable_regset (regsets_info
, regset
);
5318 else if (errno
== ESRCH
)
5320 /* At this point, ESRCH should mean the process is
5321 already gone, in which case we simply ignore attempts
5322 to change its registers. See also the related
5323 comment in linux_resume_one_lwp. */
5329 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5332 else if (regset
->type
== GENERAL_REGS
)
5333 saw_general_regs
= 1;
5336 if (saw_general_regs
)
5342 #else /* !HAVE_LINUX_REGSETS */
5344 #define use_linux_regsets 0
5345 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5346 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5350 /* Return 1 if register REGNO is supported by one of the regset ptrace
5351 calls or 0 if it has to be transferred individually. */
5354 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5356 unsigned char mask
= 1 << (regno
% 8);
5357 size_t index
= regno
/ 8;
5359 return (use_linux_regsets
5360 && (regs_info
->regset_bitmap
== NULL
5361 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5364 #ifdef HAVE_LINUX_USRREGS
5367 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5371 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5372 error ("Invalid register number %d.", regnum
);
5374 addr
= usrregs
->regmap
[regnum
];
5379 /* Fetch one register. */
5381 fetch_register (const struct usrregs_info
*usrregs
,
5382 struct regcache
*regcache
, int regno
)
5389 if (regno
>= usrregs
->num_regs
)
5391 if ((*the_low_target
.cannot_fetch_register
) (regno
))
5394 regaddr
= register_addr (usrregs
, regno
);
5398 size
= ((register_size (regcache
->tdesc
, regno
)
5399 + sizeof (PTRACE_XFER_TYPE
) - 1)
5400 & -sizeof (PTRACE_XFER_TYPE
));
5401 buf
= (char *) alloca (size
);
5403 pid
= lwpid_of (current_thread
);
5404 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5407 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5408 ptrace (PTRACE_PEEKUSER
, pid
,
5409 /* Coerce to a uintptr_t first to avoid potential gcc warning
5410 of coercing an 8 byte integer to a 4 byte pointer. */
5411 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5412 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5414 error ("reading register %d: %s", regno
, strerror (errno
));
5417 if (the_low_target
.supply_ptrace_register
)
5418 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
5420 supply_register (regcache
, regno
, buf
);
5423 /* Store one register. */
5425 store_register (const struct usrregs_info
*usrregs
,
5426 struct regcache
*regcache
, int regno
)
5433 if (regno
>= usrregs
->num_regs
)
5435 if ((*the_low_target
.cannot_store_register
) (regno
))
5438 regaddr
= register_addr (usrregs
, regno
);
5442 size
= ((register_size (regcache
->tdesc
, regno
)
5443 + sizeof (PTRACE_XFER_TYPE
) - 1)
5444 & -sizeof (PTRACE_XFER_TYPE
));
5445 buf
= (char *) alloca (size
);
5446 memset (buf
, 0, size
);
5448 if (the_low_target
.collect_ptrace_register
)
5449 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
5451 collect_register (regcache
, regno
, buf
);
5453 pid
= lwpid_of (current_thread
);
5454 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5457 ptrace (PTRACE_POKEUSER
, pid
,
5458 /* Coerce to a uintptr_t first to avoid potential gcc warning
5459 about coercing an 8 byte integer to a 4 byte pointer. */
5460 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5461 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5464 /* At this point, ESRCH should mean the process is
5465 already gone, in which case we simply ignore attempts
5466 to change its registers. See also the related
5467 comment in linux_resume_one_lwp. */
5471 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
5472 error ("writing register %d: %s", regno
, strerror (errno
));
5474 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5478 /* Fetch all registers, or just one, from the child process.
5479 If REGNO is -1, do this for all registers, skipping any that are
5480 assumed to have been retrieved by regsets_fetch_inferior_registers,
5481 unless ALL is non-zero.
5482 Otherwise, REGNO specifies which register (so we can save time). */
5484 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
5485 struct regcache
*regcache
, int regno
, int all
)
5487 struct usrregs_info
*usr
= regs_info
->usrregs
;
5491 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5492 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5493 fetch_register (usr
, regcache
, regno
);
5496 fetch_register (usr
, regcache
, regno
);
5499 /* Store our register values back into the inferior.
5500 If REGNO is -1, do this for all registers, skipping any that are
5501 assumed to have been saved by regsets_store_inferior_registers,
5502 unless ALL is non-zero.
5503 Otherwise, REGNO specifies which register (so we can save time). */
5505 usr_store_inferior_registers (const struct regs_info
*regs_info
,
5506 struct regcache
*regcache
, int regno
, int all
)
5508 struct usrregs_info
*usr
= regs_info
->usrregs
;
5512 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5513 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5514 store_register (usr
, regcache
, regno
);
5517 store_register (usr
, regcache
, regno
);
5520 #else /* !HAVE_LINUX_USRREGS */
5522 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5523 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5529 linux_fetch_registers (struct regcache
*regcache
, int regno
)
5533 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5537 if (the_low_target
.fetch_register
!= NULL
5538 && regs_info
->usrregs
!= NULL
)
5539 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5540 (*the_low_target
.fetch_register
) (regcache
, regno
);
5542 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5543 if (regs_info
->usrregs
!= NULL
)
5544 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5548 if (the_low_target
.fetch_register
!= NULL
5549 && (*the_low_target
.fetch_register
) (regcache
, regno
))
5552 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5554 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5556 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5557 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5562 linux_store_registers (struct regcache
*regcache
, int regno
)
5566 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5570 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5572 if (regs_info
->usrregs
!= NULL
)
5573 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5577 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5579 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5581 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5582 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5587 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5588 to debugger memory starting at MYADDR. */
5591 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5593 int pid
= lwpid_of (current_thread
);
5594 register PTRACE_XFER_TYPE
*buffer
;
5595 register CORE_ADDR addr
;
5602 /* Try using /proc. Don't bother for one word. */
5603 if (len
>= 3 * sizeof (long))
5607 /* We could keep this file open and cache it - possibly one per
5608 thread. That requires some juggling, but is even faster. */
5609 sprintf (filename
, "/proc/%d/mem", pid
);
5610 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5614 /* If pread64 is available, use it. It's faster if the kernel
5615 supports it (only one syscall), and it's 64-bit safe even on
5616 32-bit platforms (for instance, SPARC debugging a SPARC64
5619 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5622 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5623 bytes
= read (fd
, myaddr
, len
);
5630 /* Some data was read, we'll try to get the rest with ptrace. */
5640 /* Round starting address down to longword boundary. */
5641 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5642 /* Round ending address up; get number of longwords that makes. */
5643 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5644 / sizeof (PTRACE_XFER_TYPE
));
5645 /* Allocate buffer of that many longwords. */
5646 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5648 /* Read all the longwords */
5650 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5652 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5653 about coercing an 8 byte integer to a 4 byte pointer. */
5654 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5655 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5656 (PTRACE_TYPE_ARG4
) 0);
5662 /* Copy appropriate bytes out of the buffer. */
5665 i
*= sizeof (PTRACE_XFER_TYPE
);
5666 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5668 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5675 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5676 memory at MEMADDR. On failure (cannot write to the inferior)
5677 returns the value of errno. Always succeeds if LEN is zero. */
5680 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5683 /* Round starting address down to longword boundary. */
5684 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5685 /* Round ending address up; get number of longwords that makes. */
5687 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5688 / sizeof (PTRACE_XFER_TYPE
);
5690 /* Allocate buffer of that many longwords. */
5691 register PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5693 int pid
= lwpid_of (current_thread
);
5697 /* Zero length write always succeeds. */
5703 /* Dump up to four bytes. */
5704 char str
[4 * 2 + 1];
5706 int dump
= len
< 4 ? len
: 4;
5708 for (i
= 0; i
< dump
; i
++)
5710 sprintf (p
, "%02x", myaddr
[i
]);
5715 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5716 str
, (long) memaddr
, pid
);
5719 /* Fill start and end extra bytes of buffer with existing memory data. */
5722 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5723 about coercing an 8 byte integer to a 4 byte pointer. */
5724 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5725 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5726 (PTRACE_TYPE_ARG4
) 0);
5734 = ptrace (PTRACE_PEEKTEXT
, pid
,
5735 /* Coerce to a uintptr_t first to avoid potential gcc warning
5736 about coercing an 8 byte integer to a 4 byte pointer. */
5737 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5738 * sizeof (PTRACE_XFER_TYPE
)),
5739 (PTRACE_TYPE_ARG4
) 0);
5744 /* Copy data to be written over corresponding part of buffer. */
5746 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5749 /* Write the entire buffer. */
5751 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5754 ptrace (PTRACE_POKETEXT
, pid
,
5755 /* Coerce to a uintptr_t first to avoid potential gcc warning
5756 about coercing an 8 byte integer to a 4 byte pointer. */
5757 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5758 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5767 linux_look_up_symbols (void)
5769 #ifdef USE_THREAD_DB
5770 struct process_info
*proc
= current_process ();
5772 if (proc
->priv
->thread_db
!= NULL
)
5780 linux_request_interrupt (void)
5782 extern unsigned long signal_pid
;
5784 /* Send a SIGINT to the process group. This acts just like the user
5785 typed a ^C on the controlling terminal. */
5786 kill (-signal_pid
, SIGINT
);
5789 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5790 to debugger memory starting at MYADDR. */
5793 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5795 char filename
[PATH_MAX
];
5797 int pid
= lwpid_of (current_thread
);
5799 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5801 fd
= open (filename
, O_RDONLY
);
5805 if (offset
!= (CORE_ADDR
) 0
5806 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5809 n
= read (fd
, myaddr
, len
);
5816 /* These breakpoint and watchpoint related wrapper functions simply
5817 pass on the function call if the target has registered a
5818 corresponding function. */
5821 linux_supports_z_point_type (char z_type
)
5823 return (the_low_target
.supports_z_point_type
!= NULL
5824 && the_low_target
.supports_z_point_type (z_type
));
5828 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5829 int size
, struct raw_breakpoint
*bp
)
5831 if (type
== raw_bkpt_type_sw
)
5832 return insert_memory_breakpoint (bp
);
5833 else if (the_low_target
.insert_point
!= NULL
)
5834 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5836 /* Unsupported (see target.h). */
5841 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5842 int size
, struct raw_breakpoint
*bp
)
5844 if (type
== raw_bkpt_type_sw
)
5845 return remove_memory_breakpoint (bp
);
5846 else if (the_low_target
.remove_point
!= NULL
)
5847 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5849 /* Unsupported (see target.h). */
5853 /* Implement the to_stopped_by_sw_breakpoint target_ops
5857 linux_stopped_by_sw_breakpoint (void)
5859 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5861 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5864 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5868 linux_supports_stopped_by_sw_breakpoint (void)
5870 return USE_SIGTRAP_SIGINFO
;
5873 /* Implement the to_stopped_by_hw_breakpoint target_ops
5877 linux_stopped_by_hw_breakpoint (void)
5879 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5881 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5884 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5888 linux_supports_stopped_by_hw_breakpoint (void)
5890 return USE_SIGTRAP_SIGINFO
;
5893 /* Implement the supports_hardware_single_step target_ops method. */
5896 linux_supports_hardware_single_step (void)
5898 return can_hardware_single_step ();
5902 linux_supports_software_single_step (void)
5904 return can_software_single_step ();
5908 linux_stopped_by_watchpoint (void)
5910 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5912 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5916 linux_stopped_data_address (void)
5918 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5920 return lwp
->stopped_data_address
;
5923 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5924 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5925 && defined(PT_TEXT_END_ADDR)
5927 /* This is only used for targets that define PT_TEXT_ADDR,
5928 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5929 the target has different ways of acquiring this information, like
5932 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5933 to tell gdb about. */
5936 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5938 unsigned long text
, text_end
, data
;
5939 int pid
= lwpid_of (current_thread
);
5943 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5944 (PTRACE_TYPE_ARG4
) 0);
5945 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5946 (PTRACE_TYPE_ARG4
) 0);
5947 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5948 (PTRACE_TYPE_ARG4
) 0);
5952 /* Both text and data offsets produced at compile-time (and so
5953 used by gdb) are relative to the beginning of the program,
5954 with the data segment immediately following the text segment.
5955 However, the actual runtime layout in memory may put the data
5956 somewhere else, so when we send gdb a data base-address, we
5957 use the real data base address and subtract the compile-time
5958 data base-address from it (which is just the length of the
5959 text segment). BSS immediately follows data in both
5962 *data_p
= data
- (text_end
- text
);
5971 linux_qxfer_osdata (const char *annex
,
5972 unsigned char *readbuf
, unsigned const char *writebuf
,
5973 CORE_ADDR offset
, int len
)
5975 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5978 /* Convert a native/host siginfo object, into/from the siginfo in the
5979 layout of the inferiors' architecture. */
5982 siginfo_fixup (siginfo_t
*siginfo
, gdb_byte
*inf_siginfo
, int direction
)
5986 if (the_low_target
.siginfo_fixup
!= NULL
)
5987 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5989 /* If there was no callback, or the callback didn't do anything,
5990 then just do a straight memcpy. */
5994 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5996 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
6001 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
6002 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
6006 gdb_byte inf_siginfo
[sizeof (siginfo_t
)];
6008 if (current_thread
== NULL
)
6011 pid
= lwpid_of (current_thread
);
6014 debug_printf ("%s siginfo for lwp %d.\n",
6015 readbuf
!= NULL
? "Reading" : "Writing",
6018 if (offset
>= sizeof (siginfo
))
6021 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6024 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6025 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6026 inferior with a 64-bit GDBSERVER should look the same as debugging it
6027 with a 32-bit GDBSERVER, we need to convert it. */
6028 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
6030 if (offset
+ len
> sizeof (siginfo
))
6031 len
= sizeof (siginfo
) - offset
;
6033 if (readbuf
!= NULL
)
6034 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
6037 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
6039 /* Convert back to ptrace layout before flushing it out. */
6040 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
6042 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6049 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6050 so we notice when children change state; as the handler for the
6051 sigsuspend in my_waitpid. */
6054 sigchld_handler (int signo
)
6056 int old_errno
= errno
;
6062 /* fprintf is not async-signal-safe, so call write
6064 if (write (2, "sigchld_handler\n",
6065 sizeof ("sigchld_handler\n") - 1) < 0)
6066 break; /* just ignore */
6070 if (target_is_async_p ())
6071 async_file_mark (); /* trigger a linux_wait */
6077 linux_supports_non_stop (void)
6083 linux_async (int enable
)
6085 int previous
= target_is_async_p ();
6088 debug_printf ("linux_async (%d), previous=%d\n",
6091 if (previous
!= enable
)
6094 sigemptyset (&mask
);
6095 sigaddset (&mask
, SIGCHLD
);
6097 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
6101 if (pipe (linux_event_pipe
) == -1)
6103 linux_event_pipe
[0] = -1;
6104 linux_event_pipe
[1] = -1;
6105 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6107 warning ("creating event pipe failed.");
6111 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
6112 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
6114 /* Register the event loop handler. */
6115 add_file_handler (linux_event_pipe
[0],
6116 handle_target_event
, NULL
);
6118 /* Always trigger a linux_wait. */
6123 delete_file_handler (linux_event_pipe
[0]);
6125 close (linux_event_pipe
[0]);
6126 close (linux_event_pipe
[1]);
6127 linux_event_pipe
[0] = -1;
6128 linux_event_pipe
[1] = -1;
6131 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6138 linux_start_non_stop (int nonstop
)
6140 /* Register or unregister from event-loop accordingly. */
6141 linux_async (nonstop
);
6143 if (target_is_async_p () != (nonstop
!= 0))
6150 linux_supports_multi_process (void)
6155 /* Check if fork events are supported. */
6158 linux_supports_fork_events (void)
6160 return linux_supports_tracefork ();
6163 /* Check if vfork events are supported. */
6166 linux_supports_vfork_events (void)
6168 return linux_supports_tracefork ();
6171 /* Check if exec events are supported. */
6174 linux_supports_exec_events (void)
6176 return linux_supports_traceexec ();
6179 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
6180 options for the specified lwp. */
6183 reset_lwp_ptrace_options_callback (struct inferior_list_entry
*entry
,
6186 struct thread_info
*thread
= (struct thread_info
*) entry
;
6187 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6191 /* Stop the lwp so we can modify its ptrace options. */
6192 lwp
->must_set_ptrace_flags
= 1;
6193 linux_stop_lwp (lwp
);
6197 /* Already stopped; go ahead and set the ptrace options. */
6198 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6199 int options
= linux_low_ptrace_options (proc
->attached
);
6201 linux_enable_event_reporting (lwpid_of (thread
), options
);
6202 lwp
->must_set_ptrace_flags
= 0;
6208 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6209 ptrace flags for all inferiors. This is in case the new GDB connection
6210 doesn't support the same set of events that the previous one did. */
6213 linux_handle_new_gdb_connection (void)
6217 /* Request that all the lwps reset their ptrace options. */
6218 find_inferior (&all_threads
, reset_lwp_ptrace_options_callback
, &pid
);
6222 linux_supports_disable_randomization (void)
6224 #ifdef HAVE_PERSONALITY
6232 linux_supports_agent (void)
6238 linux_supports_range_stepping (void)
6240 if (*the_low_target
.supports_range_stepping
== NULL
)
6243 return (*the_low_target
.supports_range_stepping
) ();
6246 /* Enumerate spufs IDs for process PID. */
6248 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
6254 struct dirent
*entry
;
6256 sprintf (path
, "/proc/%ld/fd", pid
);
6257 dir
= opendir (path
);
6262 while ((entry
= readdir (dir
)) != NULL
)
6268 fd
= atoi (entry
->d_name
);
6272 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
6273 if (stat (path
, &st
) != 0)
6275 if (!S_ISDIR (st
.st_mode
))
6278 if (statfs (path
, &stfs
) != 0)
6280 if (stfs
.f_type
!= SPUFS_MAGIC
)
6283 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
6285 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
6295 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6296 object type, using the /proc file system. */
6298 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
6299 unsigned const char *writebuf
,
6300 CORE_ADDR offset
, int len
)
6302 long pid
= lwpid_of (current_thread
);
6307 if (!writebuf
&& !readbuf
)
6315 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
6318 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
6319 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
6324 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
6331 ret
= write (fd
, writebuf
, (size_t) len
);
6333 ret
= read (fd
, readbuf
, (size_t) len
);
6339 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6340 struct target_loadseg
6342 /* Core address to which the segment is mapped. */
6344 /* VMA recorded in the program header. */
6346 /* Size of this segment in memory. */
6350 # if defined PT_GETDSBT
6351 struct target_loadmap
6353 /* Protocol version number, must be zero. */
6355 /* Pointer to the DSBT table, its size, and the DSBT index. */
6356 unsigned *dsbt_table
;
6357 unsigned dsbt_size
, dsbt_index
;
6358 /* Number of segments in this map. */
6360 /* The actual memory map. */
6361 struct target_loadseg segs
[/*nsegs*/];
6363 # define LINUX_LOADMAP PT_GETDSBT
6364 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6365 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6367 struct target_loadmap
6369 /* Protocol version number, must be zero. */
6371 /* Number of segments in this map. */
6373 /* The actual memory map. */
6374 struct target_loadseg segs
[/*nsegs*/];
6376 # define LINUX_LOADMAP PTRACE_GETFDPIC
6377 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6378 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6382 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
6383 unsigned char *myaddr
, unsigned int len
)
6385 int pid
= lwpid_of (current_thread
);
6387 struct target_loadmap
*data
= NULL
;
6388 unsigned int actual_length
, copy_length
;
6390 if (strcmp (annex
, "exec") == 0)
6391 addr
= (int) LINUX_LOADMAP_EXEC
;
6392 else if (strcmp (annex
, "interp") == 0)
6393 addr
= (int) LINUX_LOADMAP_INTERP
;
6397 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6403 actual_length
= sizeof (struct target_loadmap
)
6404 + sizeof (struct target_loadseg
) * data
->nsegs
;
6406 if (offset
< 0 || offset
> actual_length
)
6409 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6410 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6414 # define linux_read_loadmap NULL
6415 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6418 linux_process_qsupported (char **features
, int count
)
6420 if (the_low_target
.process_qsupported
!= NULL
)
6421 the_low_target
.process_qsupported (features
, count
);
6425 linux_supports_catch_syscall (void)
6427 return (the_low_target
.get_syscall_trapinfo
!= NULL
6428 && linux_supports_tracesysgood ());
6432 linux_get_ipa_tdesc_idx (void)
6434 if (the_low_target
.get_ipa_tdesc_idx
== NULL
)
6437 return (*the_low_target
.get_ipa_tdesc_idx
) ();
6441 linux_supports_tracepoints (void)
6443 if (*the_low_target
.supports_tracepoints
== NULL
)
6446 return (*the_low_target
.supports_tracepoints
) ();
6450 linux_read_pc (struct regcache
*regcache
)
6452 if (the_low_target
.get_pc
== NULL
)
6455 return (*the_low_target
.get_pc
) (regcache
);
6459 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
6461 gdb_assert (the_low_target
.set_pc
!= NULL
);
6463 (*the_low_target
.set_pc
) (regcache
, pc
);
6467 linux_thread_stopped (struct thread_info
*thread
)
6469 return get_thread_lwp (thread
)->stopped
;
6472 /* This exposes stop-all-threads functionality to other modules. */
6475 linux_pause_all (int freeze
)
6477 stop_all_lwps (freeze
, NULL
);
6480 /* This exposes unstop-all-threads functionality to other gdbserver
6484 linux_unpause_all (int unfreeze
)
6486 unstop_all_lwps (unfreeze
, NULL
);
6490 linux_prepare_to_access_memory (void)
6492 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6495 linux_pause_all (1);
6500 linux_done_accessing_memory (void)
6502 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6505 linux_unpause_all (1);
6509 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
6510 CORE_ADDR collector
,
6513 CORE_ADDR
*jump_entry
,
6514 CORE_ADDR
*trampoline
,
6515 ULONGEST
*trampoline_size
,
6516 unsigned char *jjump_pad_insn
,
6517 ULONGEST
*jjump_pad_insn_size
,
6518 CORE_ADDR
*adjusted_insn_addr
,
6519 CORE_ADDR
*adjusted_insn_addr_end
,
6522 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
6523 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
6524 jump_entry
, trampoline
, trampoline_size
,
6525 jjump_pad_insn
, jjump_pad_insn_size
,
6526 adjusted_insn_addr
, adjusted_insn_addr_end
,
6530 static struct emit_ops
*
6531 linux_emit_ops (void)
6533 if (the_low_target
.emit_ops
!= NULL
)
6534 return (*the_low_target
.emit_ops
) ();
6540 linux_get_min_fast_tracepoint_insn_len (void)
6542 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
6545 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6548 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6549 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6551 char filename
[PATH_MAX
];
6553 const int auxv_size
= is_elf64
6554 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6555 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6557 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6559 fd
= open (filename
, O_RDONLY
);
6565 while (read (fd
, buf
, auxv_size
) == auxv_size
6566 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6570 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6572 switch (aux
->a_type
)
6575 *phdr_memaddr
= aux
->a_un
.a_val
;
6578 *num_phdr
= aux
->a_un
.a_val
;
6584 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6586 switch (aux
->a_type
)
6589 *phdr_memaddr
= aux
->a_un
.a_val
;
6592 *num_phdr
= aux
->a_un
.a_val
;
6600 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6602 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6603 "phdr_memaddr = %ld, phdr_num = %d",
6604 (long) *phdr_memaddr
, *num_phdr
);
6611 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6614 get_dynamic (const int pid
, const int is_elf64
)
6616 CORE_ADDR phdr_memaddr
, relocation
;
6618 unsigned char *phdr_buf
;
6619 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6621 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6624 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6625 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6627 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6630 /* Compute relocation: it is expected to be 0 for "regular" executables,
6631 non-zero for PIE ones. */
6633 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6636 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6638 if (p
->p_type
== PT_PHDR
)
6639 relocation
= phdr_memaddr
- p
->p_vaddr
;
6643 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6645 if (p
->p_type
== PT_PHDR
)
6646 relocation
= phdr_memaddr
- p
->p_vaddr
;
6649 if (relocation
== -1)
6651 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6652 any real world executables, including PIE executables, have always
6653 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6654 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6655 or present DT_DEBUG anyway (fpc binaries are statically linked).
6657 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6659 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6664 for (i
= 0; i
< num_phdr
; i
++)
6668 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6670 if (p
->p_type
== PT_DYNAMIC
)
6671 return p
->p_vaddr
+ relocation
;
6675 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6677 if (p
->p_type
== PT_DYNAMIC
)
6678 return p
->p_vaddr
+ relocation
;
6685 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6686 can be 0 if the inferior does not yet have the library list initialized.
6687 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6688 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6691 get_r_debug (const int pid
, const int is_elf64
)
6693 CORE_ADDR dynamic_memaddr
;
6694 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6695 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6698 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6699 if (dynamic_memaddr
== 0)
6702 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6706 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6707 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6711 unsigned char buf
[sizeof (Elf64_Xword
)];
6715 #ifdef DT_MIPS_RLD_MAP
6716 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6718 if (linux_read_memory (dyn
->d_un
.d_val
,
6719 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6724 #endif /* DT_MIPS_RLD_MAP */
6725 #ifdef DT_MIPS_RLD_MAP_REL
6726 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6728 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6729 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6734 #endif /* DT_MIPS_RLD_MAP_REL */
6736 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6737 map
= dyn
->d_un
.d_val
;
6739 if (dyn
->d_tag
== DT_NULL
)
6744 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6745 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6749 unsigned char buf
[sizeof (Elf32_Word
)];
6753 #ifdef DT_MIPS_RLD_MAP
6754 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6756 if (linux_read_memory (dyn
->d_un
.d_val
,
6757 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6762 #endif /* DT_MIPS_RLD_MAP */
6763 #ifdef DT_MIPS_RLD_MAP_REL
6764 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6766 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6767 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6772 #endif /* DT_MIPS_RLD_MAP_REL */
6774 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6775 map
= dyn
->d_un
.d_val
;
6777 if (dyn
->d_tag
== DT_NULL
)
6781 dynamic_memaddr
+= dyn_size
;
6787 /* Read one pointer from MEMADDR in the inferior. */
6790 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6794 /* Go through a union so this works on either big or little endian
6795 hosts, when the inferior's pointer size is smaller than the size
6796 of CORE_ADDR. It is assumed the inferior's endianness is the
6797 same of the superior's. */
6800 CORE_ADDR core_addr
;
6805 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6808 if (ptr_size
== sizeof (CORE_ADDR
))
6809 *ptr
= addr
.core_addr
;
6810 else if (ptr_size
== sizeof (unsigned int))
6813 gdb_assert_not_reached ("unhandled pointer size");
6818 struct link_map_offsets
6820 /* Offset and size of r_debug.r_version. */
6821 int r_version_offset
;
6823 /* Offset and size of r_debug.r_map. */
6826 /* Offset to l_addr field in struct link_map. */
6829 /* Offset to l_name field in struct link_map. */
6832 /* Offset to l_ld field in struct link_map. */
6835 /* Offset to l_next field in struct link_map. */
6838 /* Offset to l_prev field in struct link_map. */
6842 /* Construct qXfer:libraries-svr4:read reply. */
6845 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6846 unsigned const char *writebuf
,
6847 CORE_ADDR offset
, int len
)
6850 unsigned document_len
;
6851 struct process_info_private
*const priv
= current_process ()->priv
;
6852 char filename
[PATH_MAX
];
6855 static const struct link_map_offsets lmo_32bit_offsets
=
6857 0, /* r_version offset. */
6858 4, /* r_debug.r_map offset. */
6859 0, /* l_addr offset in link_map. */
6860 4, /* l_name offset in link_map. */
6861 8, /* l_ld offset in link_map. */
6862 12, /* l_next offset in link_map. */
6863 16 /* l_prev offset in link_map. */
6866 static const struct link_map_offsets lmo_64bit_offsets
=
6868 0, /* r_version offset. */
6869 8, /* r_debug.r_map offset. */
6870 0, /* l_addr offset in link_map. */
6871 8, /* l_name offset in link_map. */
6872 16, /* l_ld offset in link_map. */
6873 24, /* l_next offset in link_map. */
6874 32 /* l_prev offset in link_map. */
6876 const struct link_map_offsets
*lmo
;
6877 unsigned int machine
;
6879 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6880 int allocated
= 1024;
6882 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6883 int header_done
= 0;
6885 if (writebuf
!= NULL
)
6887 if (readbuf
== NULL
)
6890 pid
= lwpid_of (current_thread
);
6891 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6892 is_elf64
= elf_64_file_p (filename
, &machine
);
6893 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6894 ptr_size
= is_elf64
? 8 : 4;
6896 while (annex
[0] != '\0')
6902 sep
= strchr (annex
, '=');
6907 if (len
== 5 && startswith (annex
, "start"))
6909 else if (len
== 4 && startswith (annex
, "prev"))
6913 annex
= strchr (sep
, ';');
6920 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6927 if (priv
->r_debug
== 0)
6928 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6930 /* We failed to find DT_DEBUG. Such situation will not change
6931 for this inferior - do not retry it. Report it to GDB as
6932 E01, see for the reasons at the GDB solib-svr4.c side. */
6933 if (priv
->r_debug
== (CORE_ADDR
) -1)
6936 if (priv
->r_debug
!= 0)
6938 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6939 (unsigned char *) &r_version
,
6940 sizeof (r_version
)) != 0
6943 warning ("unexpected r_debug version %d", r_version
);
6945 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6946 &lm_addr
, ptr_size
) != 0)
6948 warning ("unable to read r_map from 0x%lx",
6949 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6954 document
= (char *) xmalloc (allocated
);
6955 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
6956 p
= document
+ strlen (document
);
6959 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6960 &l_name
, ptr_size
) == 0
6961 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6962 &l_addr
, ptr_size
) == 0
6963 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6964 &l_ld
, ptr_size
) == 0
6965 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6966 &l_prev
, ptr_size
) == 0
6967 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6968 &l_next
, ptr_size
) == 0)
6970 unsigned char libname
[PATH_MAX
];
6972 if (lm_prev
!= l_prev
)
6974 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6975 (long) lm_prev
, (long) l_prev
);
6979 /* Ignore the first entry even if it has valid name as the first entry
6980 corresponds to the main executable. The first entry should not be
6981 skipped if the dynamic loader was loaded late by a static executable
6982 (see solib-svr4.c parameter ignore_first). But in such case the main
6983 executable does not have PT_DYNAMIC present and this function already
6984 exited above due to failed get_r_debug. */
6987 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6992 /* Not checking for error because reading may stop before
6993 we've got PATH_MAX worth of characters. */
6995 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6996 libname
[sizeof (libname
) - 1] = '\0';
6997 if (libname
[0] != '\0')
6999 /* 6x the size for xml_escape_text below. */
7000 size_t len
= 6 * strlen ((char *) libname
);
7005 /* Terminate `<library-list-svr4'. */
7010 while (allocated
< p
- document
+ len
+ 200)
7012 /* Expand to guarantee sufficient storage. */
7013 uintptr_t document_len
= p
- document
;
7015 document
= (char *) xrealloc (document
, 2 * allocated
);
7017 p
= document
+ document_len
;
7020 name
= xml_escape_text ((char *) libname
);
7021 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
7022 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
7023 name
, (unsigned long) lm_addr
,
7024 (unsigned long) l_addr
, (unsigned long) l_ld
);
7035 /* Empty list; terminate `<library-list-svr4'. */
7039 strcpy (p
, "</library-list-svr4>");
7041 document_len
= strlen (document
);
7042 if (offset
< document_len
)
7043 document_len
-= offset
;
7046 if (len
> document_len
)
7049 memcpy (readbuf
, document
+ offset
, len
);
7055 #ifdef HAVE_LINUX_BTRACE
7057 /* See to_disable_btrace target method. */
7060 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
7062 enum btrace_error err
;
7064 err
= linux_disable_btrace (tinfo
);
7065 return (err
== BTRACE_ERR_NONE
? 0 : -1);
7068 /* Encode an Intel Processor Trace configuration. */
7071 linux_low_encode_pt_config (struct buffer
*buffer
,
7072 const struct btrace_data_pt_config
*config
)
7074 buffer_grow_str (buffer
, "<pt-config>\n");
7076 switch (config
->cpu
.vendor
)
7079 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7080 "model=\"%u\" stepping=\"%u\"/>\n",
7081 config
->cpu
.family
, config
->cpu
.model
,
7082 config
->cpu
.stepping
);
7089 buffer_grow_str (buffer
, "</pt-config>\n");
7092 /* Encode a raw buffer. */
7095 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
7101 /* We use hex encoding - see common/rsp-low.h. */
7102 buffer_grow_str (buffer
, "<raw>\n");
7108 elem
[0] = tohex ((*data
>> 4) & 0xf);
7109 elem
[1] = tohex (*data
++ & 0xf);
7111 buffer_grow (buffer
, elem
, 2);
7114 buffer_grow_str (buffer
, "</raw>\n");
7117 /* See to_read_btrace target method. */
7120 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
7121 enum btrace_read_type type
)
7123 struct btrace_data btrace
;
7124 struct btrace_block
*block
;
7125 enum btrace_error err
;
7128 btrace_data_init (&btrace
);
7130 err
= linux_read_btrace (&btrace
, tinfo
, type
);
7131 if (err
!= BTRACE_ERR_NONE
)
7133 if (err
== BTRACE_ERR_OVERFLOW
)
7134 buffer_grow_str0 (buffer
, "E.Overflow.");
7136 buffer_grow_str0 (buffer
, "E.Generic Error.");
7141 switch (btrace
.format
)
7143 case BTRACE_FORMAT_NONE
:
7144 buffer_grow_str0 (buffer
, "E.No Trace.");
7147 case BTRACE_FORMAT_BTS
:
7148 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7149 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7152 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
7154 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7155 paddress (block
->begin
), paddress (block
->end
));
7157 buffer_grow_str0 (buffer
, "</btrace>\n");
7160 case BTRACE_FORMAT_PT
:
7161 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7162 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7163 buffer_grow_str (buffer
, "<pt>\n");
7165 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
7167 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
7168 btrace
.variant
.pt
.size
);
7170 buffer_grow_str (buffer
, "</pt>\n");
7171 buffer_grow_str0 (buffer
, "</btrace>\n");
7175 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
7179 btrace_data_fini (&btrace
);
7183 btrace_data_fini (&btrace
);
7187 /* See to_btrace_conf target method. */
7190 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
7191 struct buffer
*buffer
)
7193 const struct btrace_config
*conf
;
7195 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7196 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7198 conf
= linux_btrace_conf (tinfo
);
7201 switch (conf
->format
)
7203 case BTRACE_FORMAT_NONE
:
7206 case BTRACE_FORMAT_BTS
:
7207 buffer_xml_printf (buffer
, "<bts");
7208 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7209 buffer_xml_printf (buffer
, " />\n");
7212 case BTRACE_FORMAT_PT
:
7213 buffer_xml_printf (buffer
, "<pt");
7214 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7215 buffer_xml_printf (buffer
, "/>\n");
7220 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7223 #endif /* HAVE_LINUX_BTRACE */
7225 /* See nat/linux-nat.h. */
7228 current_lwp_ptid (void)
7230 return ptid_of (current_thread
);
7233 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7236 linux_breakpoint_kind_from_pc (CORE_ADDR
*pcptr
)
7238 if (the_low_target
.breakpoint_kind_from_pc
!= NULL
)
7239 return (*the_low_target
.breakpoint_kind_from_pc
) (pcptr
);
7241 return default_breakpoint_kind_from_pc (pcptr
);
7244 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7246 static const gdb_byte
*
7247 linux_sw_breakpoint_from_kind (int kind
, int *size
)
7249 gdb_assert (the_low_target
.sw_breakpoint_from_kind
!= NULL
);
7251 return (*the_low_target
.sw_breakpoint_from_kind
) (kind
, size
);
7254 /* Implementation of the target_ops method
7255 "breakpoint_kind_from_current_state". */
7258 linux_breakpoint_kind_from_current_state (CORE_ADDR
*pcptr
)
7260 if (the_low_target
.breakpoint_kind_from_current_state
!= NULL
)
7261 return (*the_low_target
.breakpoint_kind_from_current_state
) (pcptr
);
7263 return linux_breakpoint_kind_from_pc (pcptr
);
7266 /* Default implementation of linux_target_ops method "set_pc" for
7267 32-bit pc register which is literally named "pc". */
7270 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
7272 uint32_t newpc
= pc
;
7274 supply_register_by_name (regcache
, "pc", &newpc
);
7277 /* Default implementation of linux_target_ops method "get_pc" for
7278 32-bit pc register which is literally named "pc". */
7281 linux_get_pc_32bit (struct regcache
*regcache
)
7285 collect_register_by_name (regcache
, "pc", &pc
);
7287 debug_printf ("stop pc is 0x%" PRIx32
"\n", pc
);
7291 /* Default implementation of linux_target_ops method "set_pc" for
7292 64-bit pc register which is literally named "pc". */
7295 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
7297 uint64_t newpc
= pc
;
7299 supply_register_by_name (regcache
, "pc", &newpc
);
7302 /* Default implementation of linux_target_ops method "get_pc" for
7303 64-bit pc register which is literally named "pc". */
7306 linux_get_pc_64bit (struct regcache
*regcache
)
7310 collect_register_by_name (regcache
, "pc", &pc
);
7312 debug_printf ("stop pc is 0x%" PRIx64
"\n", pc
);
7317 static struct target_ops linux_target_ops
= {
7318 linux_create_inferior
,
7319 linux_post_create_inferior
,
7328 linux_fetch_registers
,
7329 linux_store_registers
,
7330 linux_prepare_to_access_memory
,
7331 linux_done_accessing_memory
,
7334 linux_look_up_symbols
,
7335 linux_request_interrupt
,
7337 linux_supports_z_point_type
,
7340 linux_stopped_by_sw_breakpoint
,
7341 linux_supports_stopped_by_sw_breakpoint
,
7342 linux_stopped_by_hw_breakpoint
,
7343 linux_supports_stopped_by_hw_breakpoint
,
7344 linux_supports_hardware_single_step
,
7345 linux_stopped_by_watchpoint
,
7346 linux_stopped_data_address
,
7347 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7348 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7349 && defined(PT_TEXT_END_ADDR)
7354 #ifdef USE_THREAD_DB
7355 thread_db_get_tls_address
,
7360 hostio_last_error_from_errno
,
7363 linux_supports_non_stop
,
7365 linux_start_non_stop
,
7366 linux_supports_multi_process
,
7367 linux_supports_fork_events
,
7368 linux_supports_vfork_events
,
7369 linux_supports_exec_events
,
7370 linux_handle_new_gdb_connection
,
7371 #ifdef USE_THREAD_DB
7372 thread_db_handle_monitor_command
,
7376 linux_common_core_of_thread
,
7378 linux_process_qsupported
,
7379 linux_supports_tracepoints
,
7382 linux_thread_stopped
,
7386 linux_stabilize_threads
,
7387 linux_install_fast_tracepoint_jump_pad
,
7389 linux_supports_disable_randomization
,
7390 linux_get_min_fast_tracepoint_insn_len
,
7391 linux_qxfer_libraries_svr4
,
7392 linux_supports_agent
,
7393 #ifdef HAVE_LINUX_BTRACE
7394 linux_supports_btrace
,
7395 linux_enable_btrace
,
7396 linux_low_disable_btrace
,
7397 linux_low_read_btrace
,
7398 linux_low_btrace_conf
,
7406 linux_supports_range_stepping
,
7407 linux_proc_pid_to_exec_file
,
7408 linux_mntns_open_cloexec
,
7410 linux_mntns_readlink
,
7411 linux_breakpoint_kind_from_pc
,
7412 linux_sw_breakpoint_from_kind
,
7413 linux_proc_tid_get_name
,
7414 linux_breakpoint_kind_from_current_state
,
7415 linux_supports_software_single_step
,
7416 linux_supports_catch_syscall
,
7417 linux_get_ipa_tdesc_idx
,
7420 #ifdef HAVE_LINUX_REGSETS
7422 initialize_regsets_info (struct regsets_info
*info
)
7424 for (info
->num_regsets
= 0;
7425 info
->regsets
[info
->num_regsets
].size
>= 0;
7426 info
->num_regsets
++)
7432 initialize_low (void)
7434 struct sigaction sigchld_action
;
7436 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7437 set_target_ops (&linux_target_ops
);
7439 linux_ptrace_init_warnings ();
7441 sigchld_action
.sa_handler
= sigchld_handler
;
7442 sigemptyset (&sigchld_action
.sa_mask
);
7443 sigchld_action
.sa_flags
= SA_RESTART
;
7444 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7446 initialize_low_arch ();
7448 linux_check_ptrace_features ();