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 void unsuspend_all_lwps (struct lwp_info
*except
);
256 static int linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
257 int *wstat
, int options
);
258 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
259 static struct lwp_info
*add_lwp (ptid_t ptid
);
260 static void linux_mourn (struct process_info
*process
);
261 static int linux_stopped_by_watchpoint (void);
262 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
263 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
264 static void proceed_all_lwps (void);
265 static int finish_step_over (struct lwp_info
*lwp
);
266 static int kill_lwp (unsigned long lwpid
, int signo
);
267 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
268 static void complete_ongoing_step_over (void);
269 static int linux_low_ptrace_options (int attached
);
271 /* When the event-loop is doing a step-over, this points at the thread
273 ptid_t step_over_bkpt
;
275 /* True if the low target can hardware single-step. */
278 can_hardware_single_step (void)
280 if (the_low_target
.supports_hardware_single_step
!= NULL
)
281 return the_low_target
.supports_hardware_single_step ();
286 /* True if the low target can software single-step. Such targets
287 implement the GET_NEXT_PCS callback. */
290 can_software_single_step (void)
292 return (the_low_target
.get_next_pcs
!= NULL
);
295 /* True if the low target supports memory breakpoints. If so, we'll
296 have a GET_PC implementation. */
299 supports_breakpoints (void)
301 return (the_low_target
.get_pc
!= NULL
);
304 /* Returns true if this target can support fast tracepoints. This
305 does not mean that the in-process agent has been loaded in the
309 supports_fast_tracepoints (void)
311 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
314 /* True if LWP is stopped in its stepping range. */
317 lwp_in_step_range (struct lwp_info
*lwp
)
319 CORE_ADDR pc
= lwp
->stop_pc
;
321 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
324 struct pending_signals
328 struct pending_signals
*prev
;
331 /* The read/write ends of the pipe registered as waitable file in the
333 static int linux_event_pipe
[2] = { -1, -1 };
335 /* True if we're currently in async mode. */
336 #define target_is_async_p() (linux_event_pipe[0] != -1)
338 static void send_sigstop (struct lwp_info
*lwp
);
339 static void wait_for_sigstop (void);
341 /* Return non-zero if HEADER is a 64-bit ELF file. */
344 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
346 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
347 && header
->e_ident
[EI_MAG1
] == ELFMAG1
348 && header
->e_ident
[EI_MAG2
] == ELFMAG2
349 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
351 *machine
= header
->e_machine
;
352 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
359 /* Return non-zero if FILE is a 64-bit ELF file,
360 zero if the file is not a 64-bit ELF file,
361 and -1 if the file is not accessible or doesn't exist. */
364 elf_64_file_p (const char *file
, unsigned int *machine
)
369 fd
= open (file
, O_RDONLY
);
373 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
380 return elf_64_header_p (&header
, machine
);
383 /* Accepts an integer PID; Returns true if the executable PID is
384 running is a 64-bit ELF file.. */
387 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
391 sprintf (file
, "/proc/%d/exe", pid
);
392 return elf_64_file_p (file
, machine
);
396 delete_lwp (struct lwp_info
*lwp
)
398 struct thread_info
*thr
= get_lwp_thread (lwp
);
401 debug_printf ("deleting %ld\n", lwpid_of (thr
));
404 free (lwp
->arch_private
);
408 /* Add a process to the common process list, and set its private
411 static struct process_info
*
412 linux_add_process (int pid
, int attached
)
414 struct process_info
*proc
;
416 proc
= add_process (pid
, attached
);
417 proc
->priv
= XCNEW (struct process_info_private
);
419 if (the_low_target
.new_process
!= NULL
)
420 proc
->priv
->arch_private
= the_low_target
.new_process ();
425 static CORE_ADDR
get_pc (struct lwp_info
*lwp
);
427 /* Call the target arch_setup function on the current thread. */
430 linux_arch_setup (void)
432 the_low_target
.arch_setup ();
435 /* Call the target arch_setup function on THREAD. */
438 linux_arch_setup_thread (struct thread_info
*thread
)
440 struct thread_info
*saved_thread
;
442 saved_thread
= current_thread
;
443 current_thread
= thread
;
447 current_thread
= saved_thread
;
450 /* Handle a GNU/Linux extended wait response. If we see a clone,
451 fork, or vfork event, we need to add the new LWP to our list
452 (and return 0 so as not to report the trap to higher layers).
453 If we see an exec event, we will modify ORIG_EVENT_LWP to point
454 to a new LWP representing the new program. */
457 handle_extended_wait (struct lwp_info
**orig_event_lwp
, int wstat
)
459 struct lwp_info
*event_lwp
= *orig_event_lwp
;
460 int event
= linux_ptrace_get_extended_event (wstat
);
461 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
462 struct lwp_info
*new_lwp
;
464 gdb_assert (event_lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
466 /* All extended events we currently use are mid-syscall. Only
467 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
468 you have to be using PTRACE_SEIZE to get that. */
469 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
471 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
472 || (event
== PTRACE_EVENT_CLONE
))
475 unsigned long new_pid
;
478 /* Get the pid of the new lwp. */
479 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
482 /* If we haven't already seen the new PID stop, wait for it now. */
483 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
485 /* The new child has a pending SIGSTOP. We can't affect it until it
486 hits the SIGSTOP, but we're already attached. */
488 ret
= my_waitpid (new_pid
, &status
, __WALL
);
491 perror_with_name ("waiting for new child");
492 else if (ret
!= new_pid
)
493 warning ("wait returned unexpected PID %d", ret
);
494 else if (!WIFSTOPPED (status
))
495 warning ("wait returned unexpected status 0x%x", status
);
498 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
500 struct process_info
*parent_proc
;
501 struct process_info
*child_proc
;
502 struct lwp_info
*child_lwp
;
503 struct thread_info
*child_thr
;
504 struct target_desc
*tdesc
;
506 ptid
= ptid_build (new_pid
, new_pid
, 0);
510 debug_printf ("HEW: Got fork event from LWP %ld, "
512 ptid_get_lwp (ptid_of (event_thr
)),
513 ptid_get_pid (ptid
));
516 /* Add the new process to the tables and clone the breakpoint
517 lists of the parent. We need to do this even if the new process
518 will be detached, since we will need the process object and the
519 breakpoints to remove any breakpoints from memory when we
520 detach, and the client side will access registers. */
521 child_proc
= linux_add_process (new_pid
, 0);
522 gdb_assert (child_proc
!= NULL
);
523 child_lwp
= add_lwp (ptid
);
524 gdb_assert (child_lwp
!= NULL
);
525 child_lwp
->stopped
= 1;
526 child_lwp
->must_set_ptrace_flags
= 1;
527 child_lwp
->status_pending_p
= 0;
528 child_thr
= get_lwp_thread (child_lwp
);
529 child_thr
->last_resume_kind
= resume_stop
;
530 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
532 /* If we're suspending all threads, leave this one suspended
533 too. If the fork/clone parent is stepping over a breakpoint,
534 all other threads have been suspended already. Leave the
535 child suspended too. */
536 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
537 || event_lwp
->bp_reinsert
!= 0)
540 debug_printf ("HEW: leaving child suspended\n");
541 child_lwp
->suspended
= 1;
544 parent_proc
= get_thread_process (event_thr
);
545 child_proc
->attached
= parent_proc
->attached
;
546 clone_all_breakpoints (&child_proc
->breakpoints
,
547 &child_proc
->raw_breakpoints
,
548 parent_proc
->breakpoints
);
550 tdesc
= XNEW (struct target_desc
);
551 copy_target_description (tdesc
, parent_proc
->tdesc
);
552 child_proc
->tdesc
= tdesc
;
554 /* Clone arch-specific process data. */
555 if (the_low_target
.new_fork
!= NULL
)
556 the_low_target
.new_fork (parent_proc
, child_proc
);
558 /* Save fork info in the parent thread. */
559 if (event
== PTRACE_EVENT_FORK
)
560 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
561 else if (event
== PTRACE_EVENT_VFORK
)
562 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
564 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
566 /* The status_pending field contains bits denoting the
567 extended event, so when the pending event is handled,
568 the handler will look at lwp->waitstatus. */
569 event_lwp
->status_pending_p
= 1;
570 event_lwp
->status_pending
= wstat
;
572 /* Report the event. */
577 debug_printf ("HEW: Got clone event "
578 "from LWP %ld, new child is LWP %ld\n",
579 lwpid_of (event_thr
), new_pid
);
581 ptid
= ptid_build (pid_of (event_thr
), new_pid
, 0);
582 new_lwp
= add_lwp (ptid
);
584 /* Either we're going to immediately resume the new thread
585 or leave it stopped. linux_resume_one_lwp is a nop if it
586 thinks the thread is currently running, so set this first
587 before calling linux_resume_one_lwp. */
588 new_lwp
->stopped
= 1;
590 /* If we're suspending all threads, leave this one suspended
591 too. If the fork/clone parent is stepping over a breakpoint,
592 all other threads have been suspended already. Leave the
593 child suspended too. */
594 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
595 || event_lwp
->bp_reinsert
!= 0)
596 new_lwp
->suspended
= 1;
598 /* Normally we will get the pending SIGSTOP. But in some cases
599 we might get another signal delivered to the group first.
600 If we do get another signal, be sure not to lose it. */
601 if (WSTOPSIG (status
) != SIGSTOP
)
603 new_lwp
->stop_expected
= 1;
604 new_lwp
->status_pending_p
= 1;
605 new_lwp
->status_pending
= status
;
607 else if (report_thread_events
)
609 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
610 new_lwp
->status_pending_p
= 1;
611 new_lwp
->status_pending
= status
;
614 /* Don't report the event. */
617 else if (event
== PTRACE_EVENT_VFORK_DONE
)
619 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
621 /* Report the event. */
624 else if (event
== PTRACE_EVENT_EXEC
&& report_exec_events
)
626 struct process_info
*proc
;
627 VEC (int) *syscalls_to_catch
;
633 debug_printf ("HEW: Got exec event from LWP %ld\n",
634 lwpid_of (event_thr
));
637 /* Get the event ptid. */
638 event_ptid
= ptid_of (event_thr
);
639 event_pid
= ptid_get_pid (event_ptid
);
641 /* Save the syscall list from the execing process. */
642 proc
= get_thread_process (event_thr
);
643 syscalls_to_catch
= proc
->syscalls_to_catch
;
644 proc
->syscalls_to_catch
= NULL
;
646 /* Delete the execing process and all its threads. */
648 current_thread
= NULL
;
650 /* Create a new process/lwp/thread. */
651 proc
= linux_add_process (event_pid
, 0);
652 event_lwp
= add_lwp (event_ptid
);
653 event_thr
= get_lwp_thread (event_lwp
);
654 gdb_assert (current_thread
== event_thr
);
655 linux_arch_setup_thread (event_thr
);
657 /* Set the event status. */
658 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
659 event_lwp
->waitstatus
.value
.execd_pathname
660 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
662 /* Mark the exec status as pending. */
663 event_lwp
->stopped
= 1;
664 event_lwp
->status_pending_p
= 1;
665 event_lwp
->status_pending
= wstat
;
666 event_thr
->last_resume_kind
= resume_continue
;
667 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
669 /* Update syscall state in the new lwp, effectively mid-syscall too. */
670 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
672 /* Restore the list to catch. Don't rely on the client, which is free
673 to avoid sending a new list when the architecture doesn't change.
674 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
675 proc
->syscalls_to_catch
= syscalls_to_catch
;
677 /* Report the event. */
678 *orig_event_lwp
= event_lwp
;
682 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
685 /* Return the PC as read from the regcache of LWP, without any
689 get_pc (struct lwp_info
*lwp
)
691 struct thread_info
*saved_thread
;
692 struct regcache
*regcache
;
695 if (the_low_target
.get_pc
== NULL
)
698 saved_thread
= current_thread
;
699 current_thread
= get_lwp_thread (lwp
);
701 regcache
= get_thread_regcache (current_thread
, 1);
702 pc
= (*the_low_target
.get_pc
) (regcache
);
705 debug_printf ("pc is 0x%lx\n", (long) pc
);
707 current_thread
= saved_thread
;
711 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
712 Fill *SYSNO with the syscall nr trapped. Fill *SYSRET with the
716 get_syscall_trapinfo (struct lwp_info
*lwp
, int *sysno
, int *sysret
)
718 struct thread_info
*saved_thread
;
719 struct regcache
*regcache
;
721 if (the_low_target
.get_syscall_trapinfo
== NULL
)
723 /* If we cannot get the syscall trapinfo, report an unknown
724 system call number and -ENOSYS return value. */
725 *sysno
= UNKNOWN_SYSCALL
;
730 saved_thread
= current_thread
;
731 current_thread
= get_lwp_thread (lwp
);
733 regcache
= get_thread_regcache (current_thread
, 1);
734 (*the_low_target
.get_syscall_trapinfo
) (regcache
, sysno
, sysret
);
738 debug_printf ("get_syscall_trapinfo sysno %d sysret %d\n",
742 current_thread
= saved_thread
;
745 static int check_stopped_by_watchpoint (struct lwp_info
*child
);
747 /* Called when the LWP stopped for a signal/trap. If it stopped for a
748 trap check what caused it (breakpoint, watchpoint, trace, etc.),
749 and save the result in the LWP's stop_reason field. If it stopped
750 for a breakpoint, decrement the PC if necessary on the lwp's
751 architecture. Returns true if we now have the LWP's stop PC. */
754 save_stop_reason (struct lwp_info
*lwp
)
757 CORE_ADDR sw_breakpoint_pc
;
758 struct thread_info
*saved_thread
;
759 #if USE_SIGTRAP_SIGINFO
763 if (the_low_target
.get_pc
== NULL
)
767 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
769 /* breakpoint_at reads from the current thread. */
770 saved_thread
= current_thread
;
771 current_thread
= get_lwp_thread (lwp
);
773 #if USE_SIGTRAP_SIGINFO
774 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
775 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
777 if (siginfo
.si_signo
== SIGTRAP
)
779 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
)
780 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
782 /* The si_code is ambiguous on this arch -- check debug
784 if (!check_stopped_by_watchpoint (lwp
))
785 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
787 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
789 /* If we determine the LWP stopped for a SW breakpoint,
790 trust it. Particularly don't check watchpoint
791 registers, because at least on s390, we'd find
792 stopped-by-watchpoint as long as there's a watchpoint
794 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
796 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
798 /* This can indicate either a hardware breakpoint or
799 hardware watchpoint. Check debug registers. */
800 if (!check_stopped_by_watchpoint (lwp
))
801 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
803 else if (siginfo
.si_code
== TRAP_TRACE
)
805 /* We may have single stepped an instruction that
806 triggered a watchpoint. In that case, on some
807 architectures (such as x86), instead of TRAP_HWBKPT,
808 si_code indicates TRAP_TRACE, and we need to check
809 the debug registers separately. */
810 if (!check_stopped_by_watchpoint (lwp
))
811 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
816 /* We may have just stepped a breakpoint instruction. E.g., in
817 non-stop mode, GDB first tells the thread A to step a range, and
818 then the user inserts a breakpoint inside the range. In that
819 case we need to report the breakpoint PC. */
820 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
821 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
822 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
824 if (hardware_breakpoint_inserted_here (pc
))
825 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
827 if (lwp
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
)
828 check_stopped_by_watchpoint (lwp
);
831 if (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
835 struct thread_info
*thr
= get_lwp_thread (lwp
);
837 debug_printf ("CSBB: %s stopped by software breakpoint\n",
838 target_pid_to_str (ptid_of (thr
)));
841 /* Back up the PC if necessary. */
842 if (pc
!= sw_breakpoint_pc
)
844 struct regcache
*regcache
845 = get_thread_regcache (current_thread
, 1);
846 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
849 /* Update this so we record the correct stop PC below. */
850 pc
= sw_breakpoint_pc
;
852 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
)
856 struct thread_info
*thr
= get_lwp_thread (lwp
);
858 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
859 target_pid_to_str (ptid_of (thr
)));
862 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
866 struct thread_info
*thr
= get_lwp_thread (lwp
);
868 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
869 target_pid_to_str (ptid_of (thr
)));
872 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
876 struct thread_info
*thr
= get_lwp_thread (lwp
);
878 debug_printf ("CSBB: %s stopped by trace\n",
879 target_pid_to_str (ptid_of (thr
)));
884 current_thread
= saved_thread
;
888 static struct lwp_info
*
889 add_lwp (ptid_t ptid
)
891 struct lwp_info
*lwp
;
893 lwp
= XCNEW (struct lwp_info
);
895 lwp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
897 if (the_low_target
.new_thread
!= NULL
)
898 the_low_target
.new_thread (lwp
);
900 lwp
->thread
= add_thread (ptid
, lwp
);
905 /* Start an inferior process and returns its pid.
906 ALLARGS is a vector of program-name and args. */
909 linux_create_inferior (char *program
, char **allargs
)
911 struct lwp_info
*new_lwp
;
914 struct cleanup
*restore_personality
915 = maybe_disable_address_space_randomization (disable_randomization
);
917 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
923 perror_with_name ("fork");
928 ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
932 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
933 stdout to stderr so that inferior i/o doesn't corrupt the connection.
934 Also, redirect stdin to /dev/null. */
935 if (remote_connection_is_stdio ())
938 open ("/dev/null", O_RDONLY
);
940 if (write (2, "stdin/stdout redirected\n",
941 sizeof ("stdin/stdout redirected\n") - 1) < 0)
943 /* Errors ignored. */;
947 execv (program
, allargs
);
949 execvp (program
, allargs
);
951 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
957 do_cleanups (restore_personality
);
959 linux_add_process (pid
, 0);
961 ptid
= ptid_build (pid
, pid
, 0);
962 new_lwp
= add_lwp (ptid
);
963 new_lwp
->must_set_ptrace_flags
= 1;
968 /* Implement the post_create_inferior target_ops method. */
971 linux_post_create_inferior (void)
973 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
977 if (lwp
->must_set_ptrace_flags
)
979 struct process_info
*proc
= current_process ();
980 int options
= linux_low_ptrace_options (proc
->attached
);
982 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
983 lwp
->must_set_ptrace_flags
= 0;
987 /* Attach to an inferior process. Returns 0 on success, ERRNO on
991 linux_attach_lwp (ptid_t ptid
)
993 struct lwp_info
*new_lwp
;
994 int lwpid
= ptid_get_lwp (ptid
);
996 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
1000 new_lwp
= add_lwp (ptid
);
1002 /* We need to wait for SIGSTOP before being able to make the next
1003 ptrace call on this LWP. */
1004 new_lwp
->must_set_ptrace_flags
= 1;
1006 if (linux_proc_pid_is_stopped (lwpid
))
1009 debug_printf ("Attached to a stopped process\n");
1011 /* The process is definitely stopped. It is in a job control
1012 stop, unless the kernel predates the TASK_STOPPED /
1013 TASK_TRACED distinction, in which case it might be in a
1014 ptrace stop. Make sure it is in a ptrace stop; from there we
1015 can kill it, signal it, et cetera.
1017 First make sure there is a pending SIGSTOP. Since we are
1018 already attached, the process can not transition from stopped
1019 to running without a PTRACE_CONT; so we know this signal will
1020 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1021 probably already in the queue (unless this kernel is old
1022 enough to use TASK_STOPPED for ptrace stops); but since
1023 SIGSTOP is not an RT signal, it can only be queued once. */
1024 kill_lwp (lwpid
, SIGSTOP
);
1026 /* Finally, resume the stopped process. This will deliver the
1027 SIGSTOP (or a higher priority signal, just like normal
1028 PTRACE_ATTACH), which we'll catch later on. */
1029 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1032 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1033 brings it to a halt.
1035 There are several cases to consider here:
1037 1) gdbserver has already attached to the process and is being notified
1038 of a new thread that is being created.
1039 In this case we should ignore that SIGSTOP and resume the
1040 process. This is handled below by setting stop_expected = 1,
1041 and the fact that add_thread sets last_resume_kind ==
1044 2) This is the first thread (the process thread), and we're attaching
1045 to it via attach_inferior.
1046 In this case we want the process thread to stop.
1047 This is handled by having linux_attach set last_resume_kind ==
1048 resume_stop after we return.
1050 If the pid we are attaching to is also the tgid, we attach to and
1051 stop all the existing threads. Otherwise, we attach to pid and
1052 ignore any other threads in the same group as this pid.
1054 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1056 In this case we want the thread to stop.
1057 FIXME: This case is currently not properly handled.
1058 We should wait for the SIGSTOP but don't. Things work apparently
1059 because enough time passes between when we ptrace (ATTACH) and when
1060 gdb makes the next ptrace call on the thread.
1062 On the other hand, if we are currently trying to stop all threads, we
1063 should treat the new thread as if we had sent it a SIGSTOP. This works
1064 because we are guaranteed that the add_lwp call above added us to the
1065 end of the list, and so the new thread has not yet reached
1066 wait_for_sigstop (but will). */
1067 new_lwp
->stop_expected
= 1;
1072 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1073 already attached. Returns true if a new LWP is found, false
1077 attach_proc_task_lwp_callback (ptid_t ptid
)
1079 /* Is this a new thread? */
1080 if (find_thread_ptid (ptid
) == NULL
)
1082 int lwpid
= ptid_get_lwp (ptid
);
1086 debug_printf ("Found new lwp %d\n", lwpid
);
1088 err
= linux_attach_lwp (ptid
);
1090 /* Be quiet if we simply raced with the thread exiting. EPERM
1091 is returned if the thread's task still exists, and is marked
1092 as exited or zombie, as well as other conditions, so in that
1093 case, confirm the status in /proc/PID/status. */
1095 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1099 debug_printf ("Cannot attach to lwp %d: "
1100 "thread is gone (%d: %s)\n",
1101 lwpid
, err
, strerror (err
));
1106 warning (_("Cannot attach to lwp %d: %s"),
1108 linux_ptrace_attach_fail_reason_string (ptid
, err
));
1116 static void async_file_mark (void);
1118 /* Attach to PID. If PID is the tgid, attach to it and all
1122 linux_attach (unsigned long pid
)
1124 struct process_info
*proc
;
1125 struct thread_info
*initial_thread
;
1126 ptid_t ptid
= ptid_build (pid
, pid
, 0);
1129 /* Attach to PID. We will check for other threads
1131 err
= linux_attach_lwp (ptid
);
1133 error ("Cannot attach to process %ld: %s",
1134 pid
, linux_ptrace_attach_fail_reason_string (ptid
, err
));
1136 proc
= linux_add_process (pid
, 1);
1138 /* Don't ignore the initial SIGSTOP if we just attached to this
1139 process. It will be collected by wait shortly. */
1140 initial_thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
1141 initial_thread
->last_resume_kind
= resume_stop
;
1143 /* We must attach to every LWP. If /proc is mounted, use that to
1144 find them now. On the one hand, the inferior may be using raw
1145 clone instead of using pthreads. On the other hand, even if it
1146 is using pthreads, GDB may not be connected yet (thread_db needs
1147 to do symbol lookups, through qSymbol). Also, thread_db walks
1148 structures in the inferior's address space to find the list of
1149 threads/LWPs, and those structures may well be corrupted. Note
1150 that once thread_db is loaded, we'll still use it to list threads
1151 and associate pthread info with each LWP. */
1152 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1154 /* GDB will shortly read the xml target description for this
1155 process, to figure out the process' architecture. But the target
1156 description is only filled in when the first process/thread in
1157 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1158 that now, otherwise, if GDB is fast enough, it could read the
1159 target description _before_ that initial stop. */
1162 struct lwp_info
*lwp
;
1164 ptid_t pid_ptid
= pid_to_ptid (pid
);
1166 lwpid
= linux_wait_for_event_filtered (pid_ptid
, pid_ptid
,
1168 gdb_assert (lwpid
> 0);
1170 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
1172 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1174 lwp
->status_pending_p
= 1;
1175 lwp
->status_pending
= wstat
;
1178 initial_thread
->last_resume_kind
= resume_continue
;
1182 gdb_assert (proc
->tdesc
!= NULL
);
1195 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
1197 struct counter
*counter
= (struct counter
*) args
;
1199 if (ptid_get_pid (entry
->id
) == counter
->pid
)
1201 if (++counter
->count
> 1)
1209 last_thread_of_process_p (int pid
)
1211 struct counter counter
= { pid
, 0 };
1213 return (find_inferior (&all_threads
,
1214 second_thread_of_pid_p
, &counter
) == NULL
);
1220 linux_kill_one_lwp (struct lwp_info
*lwp
)
1222 struct thread_info
*thr
= get_lwp_thread (lwp
);
1223 int pid
= lwpid_of (thr
);
1225 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1226 there is no signal context, and ptrace(PTRACE_KILL) (or
1227 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1228 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1229 alternative is to kill with SIGKILL. We only need one SIGKILL
1230 per process, not one for each thread. But since we still support
1231 support debugging programs using raw clone without CLONE_THREAD,
1232 we send one for each thread. For years, we used PTRACE_KILL
1233 only, so we're being a bit paranoid about some old kernels where
1234 PTRACE_KILL might work better (dubious if there are any such, but
1235 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1236 second, and so we're fine everywhere. */
1239 kill_lwp (pid
, SIGKILL
);
1242 int save_errno
= errno
;
1244 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1245 target_pid_to_str (ptid_of (thr
)),
1246 save_errno
? strerror (save_errno
) : "OK");
1250 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1253 int save_errno
= errno
;
1255 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1256 target_pid_to_str (ptid_of (thr
)),
1257 save_errno
? strerror (save_errno
) : "OK");
1261 /* Kill LWP and wait for it to die. */
1264 kill_wait_lwp (struct lwp_info
*lwp
)
1266 struct thread_info
*thr
= get_lwp_thread (lwp
);
1267 int pid
= ptid_get_pid (ptid_of (thr
));
1268 int lwpid
= ptid_get_lwp (ptid_of (thr
));
1273 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1277 linux_kill_one_lwp (lwp
);
1279 /* Make sure it died. Notes:
1281 - The loop is most likely unnecessary.
1283 - We don't use linux_wait_for_event as that could delete lwps
1284 while we're iterating over them. We're not interested in
1285 any pending status at this point, only in making sure all
1286 wait status on the kernel side are collected until the
1289 - We don't use __WALL here as the __WALL emulation relies on
1290 SIGCHLD, and killing a stopped process doesn't generate
1291 one, nor an exit status.
1293 res
= my_waitpid (lwpid
, &wstat
, 0);
1294 if (res
== -1 && errno
== ECHILD
)
1295 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1296 } while (res
> 0 && WIFSTOPPED (wstat
));
1298 /* Even if it was stopped, the child may have already disappeared.
1299 E.g., if it was killed by SIGKILL. */
1300 if (res
< 0 && errno
!= ECHILD
)
1301 perror_with_name ("kill_wait_lwp");
1304 /* Callback for `find_inferior'. Kills an lwp of a given process,
1305 except the leader. */
1308 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
1310 struct thread_info
*thread
= (struct thread_info
*) entry
;
1311 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1312 int pid
= * (int *) args
;
1314 if (ptid_get_pid (entry
->id
) != pid
)
1317 /* We avoid killing the first thread here, because of a Linux kernel (at
1318 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1319 the children get a chance to be reaped, it will remain a zombie
1322 if (lwpid_of (thread
) == pid
)
1325 debug_printf ("lkop: is last of process %s\n",
1326 target_pid_to_str (entry
->id
));
1330 kill_wait_lwp (lwp
);
1335 linux_kill (int pid
)
1337 struct process_info
*process
;
1338 struct lwp_info
*lwp
;
1340 process
= find_process_pid (pid
);
1341 if (process
== NULL
)
1344 /* If we're killing a running inferior, make sure it is stopped
1345 first, as PTRACE_KILL will not work otherwise. */
1346 stop_all_lwps (0, NULL
);
1348 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1350 /* See the comment in linux_kill_one_lwp. We did not kill the first
1351 thread in the list, so do so now. */
1352 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1357 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1361 kill_wait_lwp (lwp
);
1363 the_target
->mourn (process
);
1365 /* Since we presently can only stop all lwps of all processes, we
1366 need to unstop lwps of other processes. */
1367 unstop_all_lwps (0, NULL
);
1371 /* Get pending signal of THREAD, for detaching purposes. This is the
1372 signal the thread last stopped for, which we need to deliver to the
1373 thread when detaching, otherwise, it'd be suppressed/lost. */
1376 get_detach_signal (struct thread_info
*thread
)
1378 enum gdb_signal signo
= GDB_SIGNAL_0
;
1380 struct lwp_info
*lp
= get_thread_lwp (thread
);
1382 if (lp
->status_pending_p
)
1383 status
= lp
->status_pending
;
1386 /* If the thread had been suspended by gdbserver, and it stopped
1387 cleanly, then it'll have stopped with SIGSTOP. But we don't
1388 want to deliver that SIGSTOP. */
1389 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1390 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1393 /* Otherwise, we may need to deliver the signal we
1395 status
= lp
->last_status
;
1398 if (!WIFSTOPPED (status
))
1401 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1402 target_pid_to_str (ptid_of (thread
)));
1406 /* Extended wait statuses aren't real SIGTRAPs. */
1407 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1410 debug_printf ("GPS: lwp %s had stopped with extended "
1411 "status: no pending signal\n",
1412 target_pid_to_str (ptid_of (thread
)));
1416 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1418 if (program_signals_p
&& !program_signals
[signo
])
1421 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1422 target_pid_to_str (ptid_of (thread
)),
1423 gdb_signal_to_string (signo
));
1426 else if (!program_signals_p
1427 /* If we have no way to know which signals GDB does not
1428 want to have passed to the program, assume
1429 SIGTRAP/SIGINT, which is GDB's default. */
1430 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1433 debug_printf ("GPS: lwp %s had signal %s, "
1434 "but we don't know if we should pass it. "
1435 "Default to not.\n",
1436 target_pid_to_str (ptid_of (thread
)),
1437 gdb_signal_to_string (signo
));
1443 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1444 target_pid_to_str (ptid_of (thread
)),
1445 gdb_signal_to_string (signo
));
1447 return WSTOPSIG (status
);
1452 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1454 struct thread_info
*thread
= (struct thread_info
*) entry
;
1455 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1456 int pid
= * (int *) args
;
1459 if (ptid_get_pid (entry
->id
) != pid
)
1462 /* If there is a pending SIGSTOP, get rid of it. */
1463 if (lwp
->stop_expected
)
1466 debug_printf ("Sending SIGCONT to %s\n",
1467 target_pid_to_str (ptid_of (thread
)));
1469 kill_lwp (lwpid_of (thread
), SIGCONT
);
1470 lwp
->stop_expected
= 0;
1473 /* Flush any pending changes to the process's registers. */
1474 regcache_invalidate_thread (thread
);
1476 /* Pass on any pending signal for this thread. */
1477 sig
= get_detach_signal (thread
);
1479 /* Finally, let it resume. */
1480 if (the_low_target
.prepare_to_resume
!= NULL
)
1481 the_low_target
.prepare_to_resume (lwp
);
1482 if (ptrace (PTRACE_DETACH
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1483 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1484 error (_("Can't detach %s: %s"),
1485 target_pid_to_str (ptid_of (thread
)),
1493 linux_detach (int pid
)
1495 struct process_info
*process
;
1497 process
= find_process_pid (pid
);
1498 if (process
== NULL
)
1501 /* As there's a step over already in progress, let it finish first,
1502 otherwise nesting a stabilize_threads operation on top gets real
1504 complete_ongoing_step_over ();
1506 /* Stop all threads before detaching. First, ptrace requires that
1507 the thread is stopped to sucessfully detach. Second, thread_db
1508 may need to uninstall thread event breakpoints from memory, which
1509 only works with a stopped process anyway. */
1510 stop_all_lwps (0, NULL
);
1512 #ifdef USE_THREAD_DB
1513 thread_db_detach (process
);
1516 /* Stabilize threads (move out of jump pads). */
1517 stabilize_threads ();
1519 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1521 the_target
->mourn (process
);
1523 /* Since we presently can only stop all lwps of all processes, we
1524 need to unstop lwps of other processes. */
1525 unstop_all_lwps (0, NULL
);
1529 /* Remove all LWPs that belong to process PROC from the lwp list. */
1532 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1534 struct thread_info
*thread
= (struct thread_info
*) entry
;
1535 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1536 struct process_info
*process
= (struct process_info
*) proc
;
1538 if (pid_of (thread
) == pid_of (process
))
1545 linux_mourn (struct process_info
*process
)
1547 struct process_info_private
*priv
;
1549 #ifdef USE_THREAD_DB
1550 thread_db_mourn (process
);
1553 find_inferior (&all_threads
, delete_lwp_callback
, process
);
1555 /* Freeing all private data. */
1556 priv
= process
->priv
;
1557 free (priv
->arch_private
);
1559 process
->priv
= NULL
;
1561 remove_process (process
);
1565 linux_join (int pid
)
1570 ret
= my_waitpid (pid
, &status
, 0);
1571 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1573 } while (ret
!= -1 || errno
!= ECHILD
);
1576 /* Return nonzero if the given thread is still alive. */
1578 linux_thread_alive (ptid_t ptid
)
1580 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1582 /* We assume we always know if a thread exits. If a whole process
1583 exited but we still haven't been able to report it to GDB, we'll
1584 hold on to the last lwp of the dead process. */
1586 return !lwp_is_marked_dead (lwp
);
1591 /* Return 1 if this lwp still has an interesting status pending. If
1592 not (e.g., it had stopped for a breakpoint that is gone), return
1596 thread_still_has_status_pending_p (struct thread_info
*thread
)
1598 struct lwp_info
*lp
= get_thread_lwp (thread
);
1600 if (!lp
->status_pending_p
)
1603 if (thread
->last_resume_kind
!= resume_stop
1604 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1605 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1607 struct thread_info
*saved_thread
;
1611 gdb_assert (lp
->last_status
!= 0);
1615 saved_thread
= current_thread
;
1616 current_thread
= thread
;
1618 if (pc
!= lp
->stop_pc
)
1621 debug_printf ("PC of %ld changed\n",
1626 #if !USE_SIGTRAP_SIGINFO
1627 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1628 && !(*the_low_target
.breakpoint_at
) (pc
))
1631 debug_printf ("previous SW breakpoint of %ld gone\n",
1635 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1636 && !hardware_breakpoint_inserted_here (pc
))
1639 debug_printf ("previous HW breakpoint of %ld gone\n",
1645 current_thread
= saved_thread
;
1650 debug_printf ("discarding pending breakpoint status\n");
1651 lp
->status_pending_p
= 0;
1659 /* Returns true if LWP is resumed from the client's perspective. */
1662 lwp_resumed (struct lwp_info
*lwp
)
1664 struct thread_info
*thread
= get_lwp_thread (lwp
);
1666 if (thread
->last_resume_kind
!= resume_stop
)
1669 /* Did gdb send us a `vCont;t', but we haven't reported the
1670 corresponding stop to gdb yet? If so, the thread is still
1671 resumed/running from gdb's perspective. */
1672 if (thread
->last_resume_kind
== resume_stop
1673 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1679 /* Return 1 if this lwp has an interesting status pending. */
1681 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1683 struct thread_info
*thread
= (struct thread_info
*) entry
;
1684 struct lwp_info
*lp
= get_thread_lwp (thread
);
1685 ptid_t ptid
= * (ptid_t
*) arg
;
1687 /* Check if we're only interested in events from a specific process
1688 or a specific LWP. */
1689 if (!ptid_match (ptid_of (thread
), ptid
))
1692 if (!lwp_resumed (lp
))
1695 if (lp
->status_pending_p
1696 && !thread_still_has_status_pending_p (thread
))
1698 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1702 return lp
->status_pending_p
;
1706 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1708 ptid_t ptid
= *(ptid_t
*) data
;
1711 if (ptid_get_lwp (ptid
) != 0)
1712 lwp
= ptid_get_lwp (ptid
);
1714 lwp
= ptid_get_pid (ptid
);
1716 if (ptid_get_lwp (entry
->id
) == lwp
)
1723 find_lwp_pid (ptid_t ptid
)
1725 struct inferior_list_entry
*thread
1726 = find_inferior (&all_threads
, same_lwp
, &ptid
);
1731 return get_thread_lwp ((struct thread_info
*) thread
);
1734 /* Return the number of known LWPs in the tgid given by PID. */
1739 struct inferior_list_entry
*inf
, *tmp
;
1742 ALL_INFERIORS (&all_threads
, inf
, tmp
)
1744 if (ptid_get_pid (inf
->id
) == pid
)
1751 /* The arguments passed to iterate_over_lwps. */
1753 struct iterate_over_lwps_args
1755 /* The FILTER argument passed to iterate_over_lwps. */
1758 /* The CALLBACK argument passed to iterate_over_lwps. */
1759 iterate_over_lwps_ftype
*callback
;
1761 /* The DATA argument passed to iterate_over_lwps. */
1765 /* Callback for find_inferior used by iterate_over_lwps to filter
1766 calls to the callback supplied to that function. Returning a
1767 nonzero value causes find_inferiors to stop iterating and return
1768 the current inferior_list_entry. Returning zero indicates that
1769 find_inferiors should continue iterating. */
1772 iterate_over_lwps_filter (struct inferior_list_entry
*entry
, void *args_p
)
1774 struct iterate_over_lwps_args
*args
1775 = (struct iterate_over_lwps_args
*) args_p
;
1777 if (ptid_match (entry
->id
, args
->filter
))
1779 struct thread_info
*thr
= (struct thread_info
*) entry
;
1780 struct lwp_info
*lwp
= get_thread_lwp (thr
);
1782 return (*args
->callback
) (lwp
, args
->data
);
1788 /* See nat/linux-nat.h. */
1791 iterate_over_lwps (ptid_t filter
,
1792 iterate_over_lwps_ftype callback
,
1795 struct iterate_over_lwps_args args
= {filter
, callback
, data
};
1796 struct inferior_list_entry
*entry
;
1798 entry
= find_inferior (&all_threads
, iterate_over_lwps_filter
, &args
);
1802 return get_thread_lwp ((struct thread_info
*) entry
);
1805 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1806 their exits until all other threads in the group have exited. */
1809 check_zombie_leaders (void)
1811 struct process_info
*proc
, *tmp
;
1813 ALL_PROCESSES (proc
, tmp
)
1815 pid_t leader_pid
= pid_of (proc
);
1816 struct lwp_info
*leader_lp
;
1818 leader_lp
= find_lwp_pid (pid_to_ptid (leader_pid
));
1821 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1822 "num_lwps=%d, zombie=%d\n",
1823 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1824 linux_proc_pid_is_zombie (leader_pid
));
1826 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1827 /* Check if there are other threads in the group, as we may
1828 have raced with the inferior simply exiting. */
1829 && !last_thread_of_process_p (leader_pid
)
1830 && linux_proc_pid_is_zombie (leader_pid
))
1832 /* A leader zombie can mean one of two things:
1834 - It exited, and there's an exit status pending
1835 available, or only the leader exited (not the whole
1836 program). In the latter case, we can't waitpid the
1837 leader's exit status until all other threads are gone.
1839 - There are 3 or more threads in the group, and a thread
1840 other than the leader exec'd. On an exec, the Linux
1841 kernel destroys all other threads (except the execing
1842 one) in the thread group, and resets the execing thread's
1843 tid to the tgid. No exit notification is sent for the
1844 execing thread -- from the ptracer's perspective, it
1845 appears as though the execing thread just vanishes.
1846 Until we reap all other threads except the leader and the
1847 execing thread, the leader will be zombie, and the
1848 execing thread will be in `D (disc sleep)'. As soon as
1849 all other threads are reaped, the execing thread changes
1850 it's tid to the tgid, and the previous (zombie) leader
1851 vanishes, giving place to the "new" leader. We could try
1852 distinguishing the exit and exec cases, by waiting once
1853 more, and seeing if something comes out, but it doesn't
1854 sound useful. The previous leader _does_ go away, and
1855 we'll re-add the new one once we see the exec event
1856 (which is just the same as what would happen if the
1857 previous leader did exit voluntarily before some other
1862 "CZL: Thread group leader %d zombie "
1863 "(it exited, or another thread execd).\n",
1866 delete_lwp (leader_lp
);
1871 /* Callback for `find_inferior'. Returns the first LWP that is not
1872 stopped. ARG is a PTID filter. */
1875 not_stopped_callback (struct inferior_list_entry
*entry
, void *arg
)
1877 struct thread_info
*thr
= (struct thread_info
*) entry
;
1878 struct lwp_info
*lwp
;
1879 ptid_t filter
= *(ptid_t
*) arg
;
1881 if (!ptid_match (ptid_of (thr
), filter
))
1884 lwp
= get_thread_lwp (thr
);
1891 /* Increment LWP's suspend count. */
1894 lwp_suspended_inc (struct lwp_info
*lwp
)
1898 if (debug_threads
&& lwp
->suspended
> 4)
1900 struct thread_info
*thread
= get_lwp_thread (lwp
);
1902 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1903 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1907 /* Decrement LWP's suspend count. */
1910 lwp_suspended_decr (struct lwp_info
*lwp
)
1914 if (lwp
->suspended
< 0)
1916 struct thread_info
*thread
= get_lwp_thread (lwp
);
1918 internal_error (__FILE__
, __LINE__
,
1919 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1924 /* This function should only be called if the LWP got a SIGTRAP.
1926 Handle any tracepoint steps or hits. Return true if a tracepoint
1927 event was handled, 0 otherwise. */
1930 handle_tracepoints (struct lwp_info
*lwp
)
1932 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1933 int tpoint_related_event
= 0;
1935 gdb_assert (lwp
->suspended
== 0);
1937 /* If this tracepoint hit causes a tracing stop, we'll immediately
1938 uninsert tracepoints. To do this, we temporarily pause all
1939 threads, unpatch away, and then unpause threads. We need to make
1940 sure the unpausing doesn't resume LWP too. */
1941 lwp_suspended_inc (lwp
);
1943 /* And we need to be sure that any all-threads-stopping doesn't try
1944 to move threads out of the jump pads, as it could deadlock the
1945 inferior (LWP could be in the jump pad, maybe even holding the
1948 /* Do any necessary step collect actions. */
1949 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1951 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1953 /* See if we just hit a tracepoint and do its main collect
1955 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1957 lwp_suspended_decr (lwp
);
1959 gdb_assert (lwp
->suspended
== 0);
1960 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1962 if (tpoint_related_event
)
1965 debug_printf ("got a tracepoint event\n");
1972 /* Convenience wrapper. Returns true if LWP is presently collecting a
1976 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1977 struct fast_tpoint_collect_status
*status
)
1979 CORE_ADDR thread_area
;
1980 struct thread_info
*thread
= get_lwp_thread (lwp
);
1982 if (the_low_target
.get_thread_area
== NULL
)
1985 /* Get the thread area address. This is used to recognize which
1986 thread is which when tracing with the in-process agent library.
1987 We don't read anything from the address, and treat it as opaque;
1988 it's the address itself that we assume is unique per-thread. */
1989 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
1992 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1995 /* The reason we resume in the caller, is because we want to be able
1996 to pass lwp->status_pending as WSTAT, and we need to clear
1997 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1998 refuses to resume. */
2001 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
2003 struct thread_info
*saved_thread
;
2005 saved_thread
= current_thread
;
2006 current_thread
= get_lwp_thread (lwp
);
2009 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
2010 && supports_fast_tracepoints ()
2011 && agent_loaded_p ())
2013 struct fast_tpoint_collect_status status
;
2017 debug_printf ("Checking whether LWP %ld needs to move out of the "
2019 lwpid_of (current_thread
));
2021 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
2024 || (WSTOPSIG (*wstat
) != SIGILL
2025 && WSTOPSIG (*wstat
) != SIGFPE
2026 && WSTOPSIG (*wstat
) != SIGSEGV
2027 && WSTOPSIG (*wstat
) != SIGBUS
))
2029 lwp
->collecting_fast_tracepoint
= r
;
2033 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
2035 /* Haven't executed the original instruction yet.
2036 Set breakpoint there, and wait till it's hit,
2037 then single-step until exiting the jump pad. */
2038 lwp
->exit_jump_pad_bkpt
2039 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
2043 debug_printf ("Checking whether LWP %ld needs to move out of "
2044 "the jump pad...it does\n",
2045 lwpid_of (current_thread
));
2046 current_thread
= saved_thread
;
2053 /* If we get a synchronous signal while collecting, *and*
2054 while executing the (relocated) original instruction,
2055 reset the PC to point at the tpoint address, before
2056 reporting to GDB. Otherwise, it's an IPA lib bug: just
2057 report the signal to GDB, and pray for the best. */
2059 lwp
->collecting_fast_tracepoint
= 0;
2062 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
2063 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2066 struct regcache
*regcache
;
2068 /* The si_addr on a few signals references the address
2069 of the faulting instruction. Adjust that as
2071 if ((WSTOPSIG (*wstat
) == SIGILL
2072 || WSTOPSIG (*wstat
) == SIGFPE
2073 || WSTOPSIG (*wstat
) == SIGBUS
2074 || WSTOPSIG (*wstat
) == SIGSEGV
)
2075 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2076 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2077 /* Final check just to make sure we don't clobber
2078 the siginfo of non-kernel-sent signals. */
2079 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2081 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2082 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2083 (PTRACE_TYPE_ARG3
) 0, &info
);
2086 regcache
= get_thread_regcache (current_thread
, 1);
2087 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
2088 lwp
->stop_pc
= status
.tpoint_addr
;
2090 /* Cancel any fast tracepoint lock this thread was
2092 force_unlock_trace_buffer ();
2095 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2098 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2099 "stopping all threads momentarily.\n");
2101 stop_all_lwps (1, lwp
);
2103 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2104 lwp
->exit_jump_pad_bkpt
= NULL
;
2106 unstop_all_lwps (1, lwp
);
2108 gdb_assert (lwp
->suspended
>= 0);
2114 debug_printf ("Checking whether LWP %ld needs to move out of the "
2116 lwpid_of (current_thread
));
2118 current_thread
= saved_thread
;
2122 /* Enqueue one signal in the "signals to report later when out of the
2126 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2128 struct pending_signals
*p_sig
;
2129 struct thread_info
*thread
= get_lwp_thread (lwp
);
2132 debug_printf ("Deferring signal %d for LWP %ld.\n",
2133 WSTOPSIG (*wstat
), lwpid_of (thread
));
2137 struct pending_signals
*sig
;
2139 for (sig
= lwp
->pending_signals_to_report
;
2142 debug_printf (" Already queued %d\n",
2145 debug_printf (" (no more currently queued signals)\n");
2148 /* Don't enqueue non-RT signals if they are already in the deferred
2149 queue. (SIGSTOP being the easiest signal to see ending up here
2151 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2153 struct pending_signals
*sig
;
2155 for (sig
= lwp
->pending_signals_to_report
;
2159 if (sig
->signal
== WSTOPSIG (*wstat
))
2162 debug_printf ("Not requeuing already queued non-RT signal %d"
2171 p_sig
= XCNEW (struct pending_signals
);
2172 p_sig
->prev
= lwp
->pending_signals_to_report
;
2173 p_sig
->signal
= WSTOPSIG (*wstat
);
2175 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2178 lwp
->pending_signals_to_report
= p_sig
;
2181 /* Dequeue one signal from the "signals to report later when out of
2182 the jump pad" list. */
2185 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2187 struct thread_info
*thread
= get_lwp_thread (lwp
);
2189 if (lwp
->pending_signals_to_report
!= NULL
)
2191 struct pending_signals
**p_sig
;
2193 p_sig
= &lwp
->pending_signals_to_report
;
2194 while ((*p_sig
)->prev
!= NULL
)
2195 p_sig
= &(*p_sig
)->prev
;
2197 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
2198 if ((*p_sig
)->info
.si_signo
!= 0)
2199 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2205 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2206 WSTOPSIG (*wstat
), lwpid_of (thread
));
2210 struct pending_signals
*sig
;
2212 for (sig
= lwp
->pending_signals_to_report
;
2215 debug_printf (" Still queued %d\n",
2218 debug_printf (" (no more queued signals)\n");
2227 /* Fetch the possibly triggered data watchpoint info and store it in
2230 On some archs, like x86, that use debug registers to set
2231 watchpoints, it's possible that the way to know which watched
2232 address trapped, is to check the register that is used to select
2233 which address to watch. Problem is, between setting the watchpoint
2234 and reading back which data address trapped, the user may change
2235 the set of watchpoints, and, as a consequence, GDB changes the
2236 debug registers in the inferior. To avoid reading back a stale
2237 stopped-data-address when that happens, we cache in LP the fact
2238 that a watchpoint trapped, and the corresponding data address, as
2239 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2240 registers meanwhile, we have the cached data we can rely on. */
2243 check_stopped_by_watchpoint (struct lwp_info
*child
)
2245 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2247 struct thread_info
*saved_thread
;
2249 saved_thread
= current_thread
;
2250 current_thread
= get_lwp_thread (child
);
2252 if (the_low_target
.stopped_by_watchpoint ())
2254 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2256 if (the_low_target
.stopped_data_address
!= NULL
)
2257 child
->stopped_data_address
2258 = the_low_target
.stopped_data_address ();
2260 child
->stopped_data_address
= 0;
2263 current_thread
= saved_thread
;
2266 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2269 /* Return the ptrace options that we want to try to enable. */
2272 linux_low_ptrace_options (int attached
)
2277 options
|= PTRACE_O_EXITKILL
;
2279 if (report_fork_events
)
2280 options
|= PTRACE_O_TRACEFORK
;
2282 if (report_vfork_events
)
2283 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2285 if (report_exec_events
)
2286 options
|= PTRACE_O_TRACEEXEC
;
2288 options
|= PTRACE_O_TRACESYSGOOD
;
2293 /* Do low-level handling of the event, and check if we should go on
2294 and pass it to caller code. Return the affected lwp if we are, or
2297 static struct lwp_info
*
2298 linux_low_filter_event (int lwpid
, int wstat
)
2300 struct lwp_info
*child
;
2301 struct thread_info
*thread
;
2302 int have_stop_pc
= 0;
2304 child
= find_lwp_pid (pid_to_ptid (lwpid
));
2306 /* Check for stop events reported by a process we didn't already
2307 know about - anything not already in our LWP list.
2309 If we're expecting to receive stopped processes after
2310 fork, vfork, and clone events, then we'll just add the
2311 new one to our list and go back to waiting for the event
2312 to be reported - the stopped process might be returned
2313 from waitpid before or after the event is.
2315 But note the case of a non-leader thread exec'ing after the
2316 leader having exited, and gone from our lists (because
2317 check_zombie_leaders deleted it). The non-leader thread
2318 changes its tid to the tgid. */
2320 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2321 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2325 /* A multi-thread exec after we had seen the leader exiting. */
2328 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2329 "after exec.\n", lwpid
);
2332 child_ptid
= ptid_build (lwpid
, lwpid
, 0);
2333 child
= add_lwp (child_ptid
);
2335 current_thread
= child
->thread
;
2338 /* If we didn't find a process, one of two things presumably happened:
2339 - A process we started and then detached from has exited. Ignore it.
2340 - A process we are controlling has forked and the new child's stop
2341 was reported to us by the kernel. Save its PID. */
2342 if (child
== NULL
&& WIFSTOPPED (wstat
))
2344 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2347 else if (child
== NULL
)
2350 thread
= get_lwp_thread (child
);
2354 child
->last_status
= wstat
;
2356 /* Check if the thread has exited. */
2357 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2360 debug_printf ("LLFE: %d exited.\n", lwpid
);
2362 if (finish_step_over (child
))
2364 /* Unsuspend all other LWPs, and set them back running again. */
2365 unsuspend_all_lwps (child
);
2368 /* If there is at least one more LWP, then the exit signal was
2369 not the end of the debugged application and should be
2370 ignored, unless GDB wants to hear about thread exits. */
2371 if (report_thread_events
2372 || last_thread_of_process_p (pid_of (thread
)))
2374 /* Since events are serialized to GDB core, and we can't
2375 report this one right now. Leave the status pending for
2376 the next time we're able to report it. */
2377 mark_lwp_dead (child
, wstat
);
2387 gdb_assert (WIFSTOPPED (wstat
));
2389 if (WIFSTOPPED (wstat
))
2391 struct process_info
*proc
;
2393 /* Architecture-specific setup after inferior is running. */
2394 proc
= find_process_pid (pid_of (thread
));
2395 if (proc
->tdesc
== NULL
)
2399 /* This needs to happen after we have attached to the
2400 inferior and it is stopped for the first time, but
2401 before we access any inferior registers. */
2402 linux_arch_setup_thread (thread
);
2406 /* The process is started, but GDBserver will do
2407 architecture-specific setup after the program stops at
2408 the first instruction. */
2409 child
->status_pending_p
= 1;
2410 child
->status_pending
= wstat
;
2416 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2418 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2419 int options
= linux_low_ptrace_options (proc
->attached
);
2421 linux_enable_event_reporting (lwpid
, options
);
2422 child
->must_set_ptrace_flags
= 0;
2425 /* Always update syscall_state, even if it will be filtered later. */
2426 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SYSCALL_SIGTRAP
)
2428 child
->syscall_state
2429 = (child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2430 ? TARGET_WAITKIND_SYSCALL_RETURN
2431 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2435 /* Almost all other ptrace-stops are known to be outside of system
2436 calls, with further exceptions in handle_extended_wait. */
2437 child
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2440 /* Be careful to not overwrite stop_pc until save_stop_reason is
2442 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2443 && linux_is_extended_waitstatus (wstat
))
2445 child
->stop_pc
= get_pc (child
);
2446 if (handle_extended_wait (&child
, wstat
))
2448 /* The event has been handled, so just return without
2454 if (linux_wstatus_maybe_breakpoint (wstat
))
2456 if (save_stop_reason (child
))
2461 child
->stop_pc
= get_pc (child
);
2463 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2464 && child
->stop_expected
)
2467 debug_printf ("Expected stop.\n");
2468 child
->stop_expected
= 0;
2470 if (thread
->last_resume_kind
== resume_stop
)
2472 /* We want to report the stop to the core. Treat the
2473 SIGSTOP as a normal event. */
2475 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2476 target_pid_to_str (ptid_of (thread
)));
2478 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2480 /* Stopping threads. We don't want this SIGSTOP to end up
2483 debug_printf ("LLW: SIGSTOP caught for %s "
2484 "while stopping threads.\n",
2485 target_pid_to_str (ptid_of (thread
)));
2490 /* This is a delayed SIGSTOP. Filter out the event. */
2492 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2493 child
->stepping
? "step" : "continue",
2494 target_pid_to_str (ptid_of (thread
)));
2496 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2501 child
->status_pending_p
= 1;
2502 child
->status_pending
= wstat
;
2506 /* Return true if THREAD is doing hardware single step. */
2509 maybe_hw_step (struct thread_info
*thread
)
2511 if (can_hardware_single_step ())
2515 struct process_info
*proc
= get_thread_process (thread
);
2517 /* GDBserver must insert reinsert breakpoint for software
2519 gdb_assert (has_reinsert_breakpoints (proc
));
2524 /* Resume LWPs that are currently stopped without any pending status
2525 to report, but are resumed from the core's perspective. */
2528 resume_stopped_resumed_lwps (struct inferior_list_entry
*entry
)
2530 struct thread_info
*thread
= (struct thread_info
*) entry
;
2531 struct lwp_info
*lp
= get_thread_lwp (thread
);
2535 && !lp
->status_pending_p
2536 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2538 int step
= thread
->last_resume_kind
== resume_step
;
2541 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2542 target_pid_to_str (ptid_of (thread
)),
2543 paddress (lp
->stop_pc
),
2546 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2550 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2551 match FILTER_PTID (leaving others pending). The PTIDs can be:
2552 minus_one_ptid, to specify any child; a pid PTID, specifying all
2553 lwps of a thread group; or a PTID representing a single lwp. Store
2554 the stop status through the status pointer WSTAT. OPTIONS is
2555 passed to the waitpid call. Return 0 if no event was found and
2556 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2557 was found. Return the PID of the stopped child otherwise. */
2560 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2561 int *wstatp
, int options
)
2563 struct thread_info
*event_thread
;
2564 struct lwp_info
*event_child
, *requested_child
;
2565 sigset_t block_mask
, prev_mask
;
2568 /* N.B. event_thread points to the thread_info struct that contains
2569 event_child. Keep them in sync. */
2570 event_thread
= NULL
;
2572 requested_child
= NULL
;
2574 /* Check for a lwp with a pending status. */
2576 if (ptid_equal (filter_ptid
, minus_one_ptid
) || ptid_is_pid (filter_ptid
))
2578 event_thread
= (struct thread_info
*)
2579 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2580 if (event_thread
!= NULL
)
2581 event_child
= get_thread_lwp (event_thread
);
2582 if (debug_threads
&& event_thread
)
2583 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2585 else if (!ptid_equal (filter_ptid
, null_ptid
))
2587 requested_child
= find_lwp_pid (filter_ptid
);
2589 if (stopping_threads
== NOT_STOPPING_THREADS
2590 && requested_child
->status_pending_p
2591 && requested_child
->collecting_fast_tracepoint
)
2593 enqueue_one_deferred_signal (requested_child
,
2594 &requested_child
->status_pending
);
2595 requested_child
->status_pending_p
= 0;
2596 requested_child
->status_pending
= 0;
2597 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2600 if (requested_child
->suspended
2601 && requested_child
->status_pending_p
)
2603 internal_error (__FILE__
, __LINE__
,
2604 "requesting an event out of a"
2605 " suspended child?");
2608 if (requested_child
->status_pending_p
)
2610 event_child
= requested_child
;
2611 event_thread
= get_lwp_thread (event_child
);
2615 if (event_child
!= NULL
)
2618 debug_printf ("Got an event from pending child %ld (%04x)\n",
2619 lwpid_of (event_thread
), event_child
->status_pending
);
2620 *wstatp
= event_child
->status_pending
;
2621 event_child
->status_pending_p
= 0;
2622 event_child
->status_pending
= 0;
2623 current_thread
= event_thread
;
2624 return lwpid_of (event_thread
);
2627 /* But if we don't find a pending event, we'll have to wait.
2629 We only enter this loop if no process has a pending wait status.
2630 Thus any action taken in response to a wait status inside this
2631 loop is responding as soon as we detect the status, not after any
2634 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2635 all signals while here. */
2636 sigfillset (&block_mask
);
2637 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2639 /* Always pull all events out of the kernel. We'll randomly select
2640 an event LWP out of all that have events, to prevent
2642 while (event_child
== NULL
)
2646 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2649 - If the thread group leader exits while other threads in the
2650 thread group still exist, waitpid(TGID, ...) hangs. That
2651 waitpid won't return an exit status until the other threads
2652 in the group are reaped.
2654 - When a non-leader thread execs, that thread just vanishes
2655 without reporting an exit (so we'd hang if we waited for it
2656 explicitly in that case). The exec event is reported to
2659 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2662 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2663 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2669 debug_printf ("LLW: waitpid %ld received %s\n",
2670 (long) ret
, status_to_str (*wstatp
));
2673 /* Filter all events. IOW, leave all events pending. We'll
2674 randomly select an event LWP out of all that have events
2676 linux_low_filter_event (ret
, *wstatp
);
2677 /* Retry until nothing comes out of waitpid. A single
2678 SIGCHLD can indicate more than one child stopped. */
2682 /* Now that we've pulled all events out of the kernel, resume
2683 LWPs that don't have an interesting event to report. */
2684 if (stopping_threads
== NOT_STOPPING_THREADS
)
2685 for_each_inferior (&all_threads
, resume_stopped_resumed_lwps
);
2687 /* ... and find an LWP with a status to report to the core, if
2689 event_thread
= (struct thread_info
*)
2690 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2691 if (event_thread
!= NULL
)
2693 event_child
= get_thread_lwp (event_thread
);
2694 *wstatp
= event_child
->status_pending
;
2695 event_child
->status_pending_p
= 0;
2696 event_child
->status_pending
= 0;
2700 /* Check for zombie thread group leaders. Those can't be reaped
2701 until all other threads in the thread group are. */
2702 check_zombie_leaders ();
2704 /* If there are no resumed children left in the set of LWPs we
2705 want to wait for, bail. We can't just block in
2706 waitpid/sigsuspend, because lwps might have been left stopped
2707 in trace-stop state, and we'd be stuck forever waiting for
2708 their status to change (which would only happen if we resumed
2709 them). Even if WNOHANG is set, this return code is preferred
2710 over 0 (below), as it is more detailed. */
2711 if ((find_inferior (&all_threads
,
2712 not_stopped_callback
,
2713 &wait_ptid
) == NULL
))
2716 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2717 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2721 /* No interesting event to report to the caller. */
2722 if ((options
& WNOHANG
))
2725 debug_printf ("WNOHANG set, no event found\n");
2727 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2731 /* Block until we get an event reported with SIGCHLD. */
2733 debug_printf ("sigsuspend'ing\n");
2735 sigsuspend (&prev_mask
);
2736 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2740 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2742 current_thread
= event_thread
;
2744 return lwpid_of (event_thread
);
2747 /* Wait for an event from child(ren) PTID. PTIDs can be:
2748 minus_one_ptid, to specify any child; a pid PTID, specifying all
2749 lwps of a thread group; or a PTID representing a single lwp. Store
2750 the stop status through the status pointer WSTAT. OPTIONS is
2751 passed to the waitpid call. Return 0 if no event was found and
2752 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2753 was found. Return the PID of the stopped child otherwise. */
2756 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2758 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2761 /* Count the LWP's that have had events. */
2764 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2766 struct thread_info
*thread
= (struct thread_info
*) entry
;
2767 struct lwp_info
*lp
= get_thread_lwp (thread
);
2768 int *count
= (int *) data
;
2770 gdb_assert (count
!= NULL
);
2772 /* Count only resumed LWPs that have an event pending. */
2773 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2774 && lp
->status_pending_p
)
2780 /* Select the LWP (if any) that is currently being single-stepped. */
2783 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2785 struct thread_info
*thread
= (struct thread_info
*) entry
;
2786 struct lwp_info
*lp
= get_thread_lwp (thread
);
2788 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2789 && thread
->last_resume_kind
== resume_step
2790 && lp
->status_pending_p
)
2796 /* Select the Nth LWP that has had an event. */
2799 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2801 struct thread_info
*thread
= (struct thread_info
*) entry
;
2802 struct lwp_info
*lp
= get_thread_lwp (thread
);
2803 int *selector
= (int *) data
;
2805 gdb_assert (selector
!= NULL
);
2807 /* Select only resumed LWPs that have an event pending. */
2808 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2809 && lp
->status_pending_p
)
2810 if ((*selector
)-- == 0)
2816 /* Select one LWP out of those that have events pending. */
2819 select_event_lwp (struct lwp_info
**orig_lp
)
2822 int random_selector
;
2823 struct thread_info
*event_thread
= NULL
;
2825 /* In all-stop, give preference to the LWP that is being
2826 single-stepped. There will be at most one, and it's the LWP that
2827 the core is most interested in. If we didn't do this, then we'd
2828 have to handle pending step SIGTRAPs somehow in case the core
2829 later continues the previously-stepped thread, otherwise we'd
2830 report the pending SIGTRAP, and the core, not having stepped the
2831 thread, wouldn't understand what the trap was for, and therefore
2832 would report it to the user as a random signal. */
2836 = (struct thread_info
*) find_inferior (&all_threads
,
2837 select_singlestep_lwp_callback
,
2839 if (event_thread
!= NULL
)
2842 debug_printf ("SEL: Select single-step %s\n",
2843 target_pid_to_str (ptid_of (event_thread
)));
2846 if (event_thread
== NULL
)
2848 /* No single-stepping LWP. Select one at random, out of those
2849 which have had events. */
2851 /* First see how many events we have. */
2852 find_inferior (&all_threads
, count_events_callback
, &num_events
);
2853 gdb_assert (num_events
> 0);
2855 /* Now randomly pick a LWP out of those that have had
2857 random_selector
= (int)
2858 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2860 if (debug_threads
&& num_events
> 1)
2861 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2862 num_events
, random_selector
);
2865 = (struct thread_info
*) find_inferior (&all_threads
,
2866 select_event_lwp_callback
,
2870 if (event_thread
!= NULL
)
2872 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2874 /* Switch the event LWP. */
2875 *orig_lp
= event_lp
;
2879 /* Decrement the suspend count of an LWP. */
2882 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2884 struct thread_info
*thread
= (struct thread_info
*) entry
;
2885 struct lwp_info
*lwp
= get_thread_lwp (thread
);
2887 /* Ignore EXCEPT. */
2891 lwp_suspended_decr (lwp
);
2895 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2899 unsuspend_all_lwps (struct lwp_info
*except
)
2901 find_inferior (&all_threads
, unsuspend_one_lwp
, except
);
2904 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2905 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2907 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2908 static ptid_t
linux_wait_1 (ptid_t ptid
,
2909 struct target_waitstatus
*ourstatus
,
2910 int target_options
);
2912 /* Stabilize threads (move out of jump pads).
2914 If a thread is midway collecting a fast tracepoint, we need to
2915 finish the collection and move it out of the jump pad before
2916 reporting the signal.
2918 This avoids recursion while collecting (when a signal arrives
2919 midway, and the signal handler itself collects), which would trash
2920 the trace buffer. In case the user set a breakpoint in a signal
2921 handler, this avoids the backtrace showing the jump pad, etc..
2922 Most importantly, there are certain things we can't do safely if
2923 threads are stopped in a jump pad (or in its callee's). For
2926 - starting a new trace run. A thread still collecting the
2927 previous run, could trash the trace buffer when resumed. The trace
2928 buffer control structures would have been reset but the thread had
2929 no way to tell. The thread could even midway memcpy'ing to the
2930 buffer, which would mean that when resumed, it would clobber the
2931 trace buffer that had been set for a new run.
2933 - we can't rewrite/reuse the jump pads for new tracepoints
2934 safely. Say you do tstart while a thread is stopped midway while
2935 collecting. When the thread is later resumed, it finishes the
2936 collection, and returns to the jump pad, to execute the original
2937 instruction that was under the tracepoint jump at the time the
2938 older run had been started. If the jump pad had been rewritten
2939 since for something else in the new run, the thread would now
2940 execute the wrong / random instructions. */
2943 linux_stabilize_threads (void)
2945 struct thread_info
*saved_thread
;
2946 struct thread_info
*thread_stuck
;
2949 = (struct thread_info
*) find_inferior (&all_threads
,
2950 stuck_in_jump_pad_callback
,
2952 if (thread_stuck
!= NULL
)
2955 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2956 lwpid_of (thread_stuck
));
2960 saved_thread
= current_thread
;
2962 stabilizing_threads
= 1;
2965 for_each_inferior (&all_threads
, move_out_of_jump_pad_callback
);
2967 /* Loop until all are stopped out of the jump pads. */
2968 while (find_inferior (&all_threads
, lwp_running
, NULL
) != NULL
)
2970 struct target_waitstatus ourstatus
;
2971 struct lwp_info
*lwp
;
2974 /* Note that we go through the full wait even loop. While
2975 moving threads out of jump pad, we need to be able to step
2976 over internal breakpoints and such. */
2977 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2979 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2981 lwp
= get_thread_lwp (current_thread
);
2984 lwp_suspended_inc (lwp
);
2986 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2987 || current_thread
->last_resume_kind
== resume_stop
)
2989 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2990 enqueue_one_deferred_signal (lwp
, &wstat
);
2995 unsuspend_all_lwps (NULL
);
2997 stabilizing_threads
= 0;
2999 current_thread
= saved_thread
;
3004 = (struct thread_info
*) find_inferior (&all_threads
,
3005 stuck_in_jump_pad_callback
,
3007 if (thread_stuck
!= NULL
)
3008 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
3009 lwpid_of (thread_stuck
));
3013 /* Convenience function that is called when the kernel reports an
3014 event that is not passed out to GDB. */
3017 ignore_event (struct target_waitstatus
*ourstatus
)
3019 /* If we got an event, there may still be others, as a single
3020 SIGCHLD can indicate more than one child stopped. This forces
3021 another target_wait call. */
3024 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3028 /* Convenience function that is called when the kernel reports an exit
3029 event. This decides whether to report the event to GDB as a
3030 process exit event, a thread exit event, or to suppress the
3034 filter_exit_event (struct lwp_info
*event_child
,
3035 struct target_waitstatus
*ourstatus
)
3037 struct thread_info
*thread
= get_lwp_thread (event_child
);
3038 ptid_t ptid
= ptid_of (thread
);
3040 if (!last_thread_of_process_p (pid_of (thread
)))
3042 if (report_thread_events
)
3043 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
3045 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3047 delete_lwp (event_child
);
3052 /* Returns 1 if GDB is interested in any event_child syscalls. */
3055 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
3057 struct thread_info
*thread
= get_lwp_thread (event_child
);
3058 struct process_info
*proc
= get_thread_process (thread
);
3060 return !VEC_empty (int, proc
->syscalls_to_catch
);
3063 /* Returns 1 if GDB is interested in the event_child syscall.
3064 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
3067 gdb_catch_this_syscall_p (struct lwp_info
*event_child
)
3071 struct thread_info
*thread
= get_lwp_thread (event_child
);
3072 struct process_info
*proc
= get_thread_process (thread
);
3074 if (VEC_empty (int, proc
->syscalls_to_catch
))
3077 if (VEC_index (int, proc
->syscalls_to_catch
, 0) == ANY_SYSCALL
)
3080 get_syscall_trapinfo (event_child
, &sysno
, &sysret
);
3082 VEC_iterate (int, proc
->syscalls_to_catch
, i
, iter
);
3090 /* Wait for process, returns status. */
3093 linux_wait_1 (ptid_t ptid
,
3094 struct target_waitstatus
*ourstatus
, int target_options
)
3097 struct lwp_info
*event_child
;
3100 int step_over_finished
;
3101 int bp_explains_trap
;
3102 int maybe_internal_trap
;
3111 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
3114 /* Translate generic target options into linux options. */
3116 if (target_options
& TARGET_WNOHANG
)
3119 bp_explains_trap
= 0;
3122 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3124 /* Find a resumed LWP, if any. */
3125 if (find_inferior (&all_threads
,
3126 status_pending_p_callback
,
3127 &minus_one_ptid
) != NULL
)
3129 else if ((find_inferior (&all_threads
,
3130 not_stopped_callback
,
3131 &minus_one_ptid
) != NULL
))
3136 if (ptid_equal (step_over_bkpt
, null_ptid
))
3137 pid
= linux_wait_for_event (ptid
, &w
, options
);
3141 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3142 target_pid_to_str (step_over_bkpt
));
3143 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
3146 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3148 gdb_assert (target_options
& TARGET_WNOHANG
);
3152 debug_printf ("linux_wait_1 ret = null_ptid, "
3153 "TARGET_WAITKIND_IGNORE\n");
3157 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3164 debug_printf ("linux_wait_1 ret = null_ptid, "
3165 "TARGET_WAITKIND_NO_RESUMED\n");
3169 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3173 event_child
= get_thread_lwp (current_thread
);
3175 /* linux_wait_for_event only returns an exit status for the last
3176 child of a process. Report it. */
3177 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3181 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3182 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3186 debug_printf ("linux_wait_1 ret = %s, exited with "
3188 target_pid_to_str (ptid_of (current_thread
)),
3195 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3196 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3200 debug_printf ("linux_wait_1 ret = %s, terminated with "
3202 target_pid_to_str (ptid_of (current_thread
)),
3208 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3209 return filter_exit_event (event_child
, ourstatus
);
3211 return ptid_of (current_thread
);
3214 /* If step-over executes a breakpoint instruction, in the case of a
3215 hardware single step it means a gdb/gdbserver breakpoint had been
3216 planted on top of a permanent breakpoint, in the case of a software
3217 single step it may just mean that gdbserver hit the reinsert breakpoint.
3218 The PC has been adjusted by save_stop_reason to point at
3219 the breakpoint address.
3220 So in the case of the hardware single step advance the PC manually
3221 past the breakpoint and in the case of software single step advance only
3222 if it's not the reinsert_breakpoint we are hitting.
3223 This avoids that a program would keep trapping a permanent breakpoint
3225 if (!ptid_equal (step_over_bkpt
, null_ptid
)
3226 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3227 && (event_child
->stepping
3228 || !reinsert_breakpoint_inserted_here (event_child
->stop_pc
)))
3230 int increment_pc
= 0;
3231 int breakpoint_kind
= 0;
3232 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3235 the_target
->breakpoint_kind_from_current_state (&stop_pc
);
3236 the_target
->sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3240 debug_printf ("step-over for %s executed software breakpoint\n",
3241 target_pid_to_str (ptid_of (current_thread
)));
3244 if (increment_pc
!= 0)
3246 struct regcache
*regcache
3247 = get_thread_regcache (current_thread
, 1);
3249 event_child
->stop_pc
+= increment_pc
;
3250 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3252 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
3253 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3257 /* If this event was not handled before, and is not a SIGTRAP, we
3258 report it. SIGILL and SIGSEGV are also treated as traps in case
3259 a breakpoint is inserted at the current PC. If this target does
3260 not support internal breakpoints at all, we also report the
3261 SIGTRAP without further processing; it's of no concern to us. */
3263 = (supports_breakpoints ()
3264 && (WSTOPSIG (w
) == SIGTRAP
3265 || ((WSTOPSIG (w
) == SIGILL
3266 || WSTOPSIG (w
) == SIGSEGV
)
3267 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
3269 if (maybe_internal_trap
)
3271 /* Handle anything that requires bookkeeping before deciding to
3272 report the event or continue waiting. */
3274 /* First check if we can explain the SIGTRAP with an internal
3275 breakpoint, or if we should possibly report the event to GDB.
3276 Do this before anything that may remove or insert a
3278 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3280 /* We have a SIGTRAP, possibly a step-over dance has just
3281 finished. If so, tweak the state machine accordingly,
3282 reinsert breakpoints and delete any reinsert (software
3283 single-step) breakpoints. */
3284 step_over_finished
= finish_step_over (event_child
);
3286 /* Now invoke the callbacks of any internal breakpoints there. */
3287 check_breakpoints (event_child
->stop_pc
);
3289 /* Handle tracepoint data collecting. This may overflow the
3290 trace buffer, and cause a tracing stop, removing
3292 trace_event
= handle_tracepoints (event_child
);
3294 if (bp_explains_trap
)
3297 debug_printf ("Hit a gdbserver breakpoint.\n");
3302 /* We have some other signal, possibly a step-over dance was in
3303 progress, and it should be cancelled too. */
3304 step_over_finished
= finish_step_over (event_child
);
3307 /* We have all the data we need. Either report the event to GDB, or
3308 resume threads and keep waiting for more. */
3310 /* If we're collecting a fast tracepoint, finish the collection and
3311 move out of the jump pad before delivering a signal. See
3312 linux_stabilize_threads. */
3315 && WSTOPSIG (w
) != SIGTRAP
3316 && supports_fast_tracepoints ()
3317 && agent_loaded_p ())
3320 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3321 "to defer or adjust it.\n",
3322 WSTOPSIG (w
), lwpid_of (current_thread
));
3324 /* Allow debugging the jump pad itself. */
3325 if (current_thread
->last_resume_kind
!= resume_step
3326 && maybe_move_out_of_jump_pad (event_child
, &w
))
3328 enqueue_one_deferred_signal (event_child
, &w
);
3331 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3332 WSTOPSIG (w
), lwpid_of (current_thread
));
3334 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
3336 return ignore_event (ourstatus
);
3340 if (event_child
->collecting_fast_tracepoint
)
3343 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3344 "Check if we're already there.\n",
3345 lwpid_of (current_thread
),
3346 event_child
->collecting_fast_tracepoint
);
3350 event_child
->collecting_fast_tracepoint
3351 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3353 if (event_child
->collecting_fast_tracepoint
!= 1)
3355 /* No longer need this breakpoint. */
3356 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3359 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3360 "stopping all threads momentarily.\n");
3362 /* Other running threads could hit this breakpoint.
3363 We don't handle moribund locations like GDB does,
3364 instead we always pause all threads when removing
3365 breakpoints, so that any step-over or
3366 decr_pc_after_break adjustment is always taken
3367 care of while the breakpoint is still
3369 stop_all_lwps (1, event_child
);
3371 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3372 event_child
->exit_jump_pad_bkpt
= NULL
;
3374 unstop_all_lwps (1, event_child
);
3376 gdb_assert (event_child
->suspended
>= 0);
3380 if (event_child
->collecting_fast_tracepoint
== 0)
3383 debug_printf ("fast tracepoint finished "
3384 "collecting successfully.\n");
3386 /* We may have a deferred signal to report. */
3387 if (dequeue_one_deferred_signal (event_child
, &w
))
3390 debug_printf ("dequeued one signal.\n");
3395 debug_printf ("no deferred signals.\n");
3397 if (stabilizing_threads
)
3399 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3400 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3404 debug_printf ("linux_wait_1 ret = %s, stopped "
3405 "while stabilizing threads\n",
3406 target_pid_to_str (ptid_of (current_thread
)));
3410 return ptid_of (current_thread
);
3416 /* Check whether GDB would be interested in this event. */
3418 /* Check if GDB is interested in this syscall. */
3420 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3421 && !gdb_catch_this_syscall_p (event_child
))
3425 debug_printf ("Ignored syscall for LWP %ld.\n",
3426 lwpid_of (current_thread
));
3429 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3431 return ignore_event (ourstatus
);
3434 /* If GDB is not interested in this signal, don't stop other
3435 threads, and don't report it to GDB. Just resume the inferior
3436 right away. We do this for threading-related signals as well as
3437 any that GDB specifically requested we ignore. But never ignore
3438 SIGSTOP if we sent it ourselves, and do not ignore signals when
3439 stepping - they may require special handling to skip the signal
3440 handler. Also never ignore signals that could be caused by a
3443 && current_thread
->last_resume_kind
!= resume_step
3445 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3446 (current_process ()->priv
->thread_db
!= NULL
3447 && (WSTOPSIG (w
) == __SIGRTMIN
3448 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3451 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3452 && !(WSTOPSIG (w
) == SIGSTOP
3453 && current_thread
->last_resume_kind
== resume_stop
)
3454 && !linux_wstatus_maybe_breakpoint (w
))))
3456 siginfo_t info
, *info_p
;
3459 debug_printf ("Ignored signal %d for LWP %ld.\n",
3460 WSTOPSIG (w
), lwpid_of (current_thread
));
3462 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3463 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3468 if (step_over_finished
)
3470 /* We cancelled this thread's step-over above. We still
3471 need to unsuspend all other LWPs, and set them back
3472 running again while the signal handler runs. */
3473 unsuspend_all_lwps (event_child
);
3475 /* Enqueue the pending signal info so that proceed_all_lwps
3477 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3479 proceed_all_lwps ();
3483 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3484 WSTOPSIG (w
), info_p
);
3486 return ignore_event (ourstatus
);
3489 /* Note that all addresses are always "out of the step range" when
3490 there's no range to begin with. */
3491 in_step_range
= lwp_in_step_range (event_child
);
3493 /* If GDB wanted this thread to single step, and the thread is out
3494 of the step range, we always want to report the SIGTRAP, and let
3495 GDB handle it. Watchpoints should always be reported. So should
3496 signals we can't explain. A SIGTRAP we can't explain could be a
3497 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3498 do, we're be able to handle GDB breakpoints on top of internal
3499 breakpoints, by handling the internal breakpoint and still
3500 reporting the event to GDB. If we don't, we're out of luck, GDB
3501 won't see the breakpoint hit. If we see a single-step event but
3502 the thread should be continuing, don't pass the trap to gdb.
3503 That indicates that we had previously finished a single-step but
3504 left the single-step pending -- see
3505 complete_ongoing_step_over. */
3506 report_to_gdb
= (!maybe_internal_trap
3507 || (current_thread
->last_resume_kind
== resume_step
3509 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3511 && !bp_explains_trap
3513 && !step_over_finished
3514 && !(current_thread
->last_resume_kind
== resume_continue
3515 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3516 || (gdb_breakpoint_here (event_child
->stop_pc
)
3517 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3518 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3519 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3521 run_breakpoint_commands (event_child
->stop_pc
);
3523 /* We found no reason GDB would want us to stop. We either hit one
3524 of our own breakpoints, or finished an internal step GDB
3525 shouldn't know about. */
3530 if (bp_explains_trap
)
3531 debug_printf ("Hit a gdbserver breakpoint.\n");
3532 if (step_over_finished
)
3533 debug_printf ("Step-over finished.\n");
3535 debug_printf ("Tracepoint event.\n");
3536 if (lwp_in_step_range (event_child
))
3537 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3538 paddress (event_child
->stop_pc
),
3539 paddress (event_child
->step_range_start
),
3540 paddress (event_child
->step_range_end
));
3543 /* We're not reporting this breakpoint to GDB, so apply the
3544 decr_pc_after_break adjustment to the inferior's regcache
3547 if (the_low_target
.set_pc
!= NULL
)
3549 struct regcache
*regcache
3550 = get_thread_regcache (current_thread
, 1);
3551 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3554 /* We may have finished stepping over a breakpoint. If so,
3555 we've stopped and suspended all LWPs momentarily except the
3556 stepping one. This is where we resume them all again. We're
3557 going to keep waiting, so use proceed, which handles stepping
3558 over the next breakpoint. */
3560 debug_printf ("proceeding all threads.\n");
3562 if (step_over_finished
)
3563 unsuspend_all_lwps (event_child
);
3565 proceed_all_lwps ();
3566 return ignore_event (ourstatus
);
3571 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3575 str
= target_waitstatus_to_string (&event_child
->waitstatus
);
3576 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3577 lwpid_of (get_lwp_thread (event_child
)), str
);
3580 if (current_thread
->last_resume_kind
== resume_step
)
3582 if (event_child
->step_range_start
== event_child
->step_range_end
)
3583 debug_printf ("GDB wanted to single-step, reporting event.\n");
3584 else if (!lwp_in_step_range (event_child
))
3585 debug_printf ("Out of step range, reporting event.\n");
3587 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3588 debug_printf ("Stopped by watchpoint.\n");
3589 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3590 debug_printf ("Stopped by GDB breakpoint.\n");
3592 debug_printf ("Hit a non-gdbserver trap event.\n");
3595 /* Alright, we're going to report a stop. */
3597 if (!stabilizing_threads
)
3599 /* In all-stop, stop all threads. */
3601 stop_all_lwps (0, NULL
);
3603 /* If we're not waiting for a specific LWP, choose an event LWP
3604 from among those that have had events. Giving equal priority
3605 to all LWPs that have had events helps prevent
3607 if (ptid_equal (ptid
, minus_one_ptid
))
3609 event_child
->status_pending_p
= 1;
3610 event_child
->status_pending
= w
;
3612 select_event_lwp (&event_child
);
3614 /* current_thread and event_child must stay in sync. */
3615 current_thread
= get_lwp_thread (event_child
);
3617 event_child
->status_pending_p
= 0;
3618 w
= event_child
->status_pending
;
3621 if (step_over_finished
)
3625 /* If we were doing a step-over, all other threads but
3626 the stepping one had been paused in start_step_over,
3627 with their suspend counts incremented. We don't want
3628 to do a full unstop/unpause, because we're in
3629 all-stop mode (so we want threads stopped), but we
3630 still need to unsuspend the other threads, to
3631 decrement their `suspended' count back. */
3632 unsuspend_all_lwps (event_child
);
3636 /* If we just finished a step-over, then all threads had
3637 been momentarily paused. In all-stop, that's fine,
3638 we want threads stopped by now anyway. In non-stop,
3639 we need to re-resume threads that GDB wanted to be
3641 unstop_all_lwps (1, event_child
);
3645 /* Stabilize threads (move out of jump pads). */
3647 stabilize_threads ();
3651 /* If we just finished a step-over, then all threads had been
3652 momentarily paused. In all-stop, that's fine, we want
3653 threads stopped by now anyway. In non-stop, we need to
3654 re-resume threads that GDB wanted to be running. */
3655 if (step_over_finished
)
3656 unstop_all_lwps (1, event_child
);
3659 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3661 /* If the reported event is an exit, fork, vfork or exec, let
3663 *ourstatus
= event_child
->waitstatus
;
3664 /* Clear the event lwp's waitstatus since we handled it already. */
3665 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3668 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3670 /* Now that we've selected our final event LWP, un-adjust its PC if
3671 it was a software breakpoint, and the client doesn't know we can
3672 adjust the breakpoint ourselves. */
3673 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3674 && !swbreak_feature
)
3676 int decr_pc
= the_low_target
.decr_pc_after_break
;
3680 struct regcache
*regcache
3681 = get_thread_regcache (current_thread
, 1);
3682 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3686 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3690 get_syscall_trapinfo (event_child
,
3691 &ourstatus
->value
.syscall_number
, &sysret
);
3692 ourstatus
->kind
= event_child
->syscall_state
;
3694 else if (current_thread
->last_resume_kind
== resume_stop
3695 && WSTOPSIG (w
) == SIGSTOP
)
3697 /* A thread that has been requested to stop by GDB with vCont;t,
3698 and it stopped cleanly, so report as SIG0. The use of
3699 SIGSTOP is an implementation detail. */
3700 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3702 else if (current_thread
->last_resume_kind
== resume_stop
3703 && WSTOPSIG (w
) != SIGSTOP
)
3705 /* A thread that has been requested to stop by GDB with vCont;t,
3706 but, it stopped for other reasons. */
3707 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3709 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3711 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3714 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
3718 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3719 target_pid_to_str (ptid_of (current_thread
)),
3720 ourstatus
->kind
, ourstatus
->value
.sig
);
3724 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3725 return filter_exit_event (event_child
, ourstatus
);
3727 return ptid_of (current_thread
);
3730 /* Get rid of any pending event in the pipe. */
3732 async_file_flush (void)
3738 ret
= read (linux_event_pipe
[0], &buf
, 1);
3739 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3742 /* Put something in the pipe, so the event loop wakes up. */
3744 async_file_mark (void)
3748 async_file_flush ();
3751 ret
= write (linux_event_pipe
[1], "+", 1);
3752 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3754 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3755 be awakened anyway. */
3759 linux_wait (ptid_t ptid
,
3760 struct target_waitstatus
*ourstatus
, int target_options
)
3764 /* Flush the async file first. */
3765 if (target_is_async_p ())
3766 async_file_flush ();
3770 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3772 while ((target_options
& TARGET_WNOHANG
) == 0
3773 && ptid_equal (event_ptid
, null_ptid
)
3774 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3776 /* If at least one stop was reported, there may be more. A single
3777 SIGCHLD can signal more than one child stop. */
3778 if (target_is_async_p ()
3779 && (target_options
& TARGET_WNOHANG
) != 0
3780 && !ptid_equal (event_ptid
, null_ptid
))
3786 /* Send a signal to an LWP. */
3789 kill_lwp (unsigned long lwpid
, int signo
)
3794 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3795 if (errno
== ENOSYS
)
3797 /* If tkill fails, then we are not using nptl threads, a
3798 configuration we no longer support. */
3799 perror_with_name (("tkill"));
3805 linux_stop_lwp (struct lwp_info
*lwp
)
3811 send_sigstop (struct lwp_info
*lwp
)
3815 pid
= lwpid_of (get_lwp_thread (lwp
));
3817 /* If we already have a pending stop signal for this process, don't
3819 if (lwp
->stop_expected
)
3822 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3828 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3830 lwp
->stop_expected
= 1;
3831 kill_lwp (pid
, SIGSTOP
);
3835 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
3837 struct thread_info
*thread
= (struct thread_info
*) entry
;
3838 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3840 /* Ignore EXCEPT. */
3851 /* Increment the suspend count of an LWP, and stop it, if not stopped
3854 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
3857 struct thread_info
*thread
= (struct thread_info
*) entry
;
3858 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3860 /* Ignore EXCEPT. */
3864 lwp_suspended_inc (lwp
);
3866 return send_sigstop_callback (entry
, except
);
3870 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3872 /* Store the exit status for later. */
3873 lwp
->status_pending_p
= 1;
3874 lwp
->status_pending
= wstat
;
3876 /* Store in waitstatus as well, as there's nothing else to process
3878 if (WIFEXITED (wstat
))
3880 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3881 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3883 else if (WIFSIGNALED (wstat
))
3885 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3886 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3889 /* Prevent trying to stop it. */
3892 /* No further stops are expected from a dead lwp. */
3893 lwp
->stop_expected
= 0;
3896 /* Return true if LWP has exited already, and has a pending exit event
3897 to report to GDB. */
3900 lwp_is_marked_dead (struct lwp_info
*lwp
)
3902 return (lwp
->status_pending_p
3903 && (WIFEXITED (lwp
->status_pending
)
3904 || WIFSIGNALED (lwp
->status_pending
)));
3907 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3910 wait_for_sigstop (void)
3912 struct thread_info
*saved_thread
;
3917 saved_thread
= current_thread
;
3918 if (saved_thread
!= NULL
)
3919 saved_tid
= saved_thread
->entry
.id
;
3921 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3924 debug_printf ("wait_for_sigstop: pulling events\n");
3926 /* Passing NULL_PTID as filter indicates we want all events to be
3927 left pending. Eventually this returns when there are no
3928 unwaited-for children left. */
3929 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
3931 gdb_assert (ret
== -1);
3933 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
3934 current_thread
= saved_thread
;
3938 debug_printf ("Previously current thread died.\n");
3940 /* We can't change the current inferior behind GDB's back,
3941 otherwise, a subsequent command may apply to the wrong
3943 current_thread
= NULL
;
3947 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3948 move it out, because we need to report the stop event to GDB. For
3949 example, if the user puts a breakpoint in the jump pad, it's
3950 because she wants to debug it. */
3953 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3955 struct thread_info
*thread
= (struct thread_info
*) entry
;
3956 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3958 if (lwp
->suspended
!= 0)
3960 internal_error (__FILE__
, __LINE__
,
3961 "LWP %ld is suspended, suspended=%d\n",
3962 lwpid_of (thread
), lwp
->suspended
);
3964 gdb_assert (lwp
->stopped
);
3966 /* Allow debugging the jump pad, gdb_collect, etc.. */
3967 return (supports_fast_tracepoints ()
3968 && agent_loaded_p ()
3969 && (gdb_breakpoint_here (lwp
->stop_pc
)
3970 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3971 || thread
->last_resume_kind
== resume_step
)
3972 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3976 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3978 struct thread_info
*thread
= (struct thread_info
*) entry
;
3979 struct thread_info
*saved_thread
;
3980 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3983 if (lwp
->suspended
!= 0)
3985 internal_error (__FILE__
, __LINE__
,
3986 "LWP %ld is suspended, suspended=%d\n",
3987 lwpid_of (thread
), lwp
->suspended
);
3989 gdb_assert (lwp
->stopped
);
3991 /* For gdb_breakpoint_here. */
3992 saved_thread
= current_thread
;
3993 current_thread
= thread
;
3995 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3997 /* Allow debugging the jump pad, gdb_collect, etc. */
3998 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3999 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
4000 && thread
->last_resume_kind
!= resume_step
4001 && maybe_move_out_of_jump_pad (lwp
, wstat
))
4004 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
4009 lwp
->status_pending_p
= 0;
4010 enqueue_one_deferred_signal (lwp
, wstat
);
4013 debug_printf ("Signal %d for LWP %ld deferred "
4015 WSTOPSIG (*wstat
), lwpid_of (thread
));
4018 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
4021 lwp_suspended_inc (lwp
);
4023 current_thread
= saved_thread
;
4027 lwp_running (struct inferior_list_entry
*entry
, void *data
)
4029 struct thread_info
*thread
= (struct thread_info
*) entry
;
4030 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4032 if (lwp_is_marked_dead (lwp
))
4039 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
4040 If SUSPEND, then also increase the suspend count of every LWP,
4044 stop_all_lwps (int suspend
, struct lwp_info
*except
)
4046 /* Should not be called recursively. */
4047 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
4052 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4053 suspend
? "stop-and-suspend" : "stop",
4055 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
4059 stopping_threads
= (suspend
4060 ? STOPPING_AND_SUSPENDING_THREADS
4061 : STOPPING_THREADS
);
4064 find_inferior (&all_threads
, suspend_and_send_sigstop_callback
, except
);
4066 find_inferior (&all_threads
, send_sigstop_callback
, except
);
4067 wait_for_sigstop ();
4068 stopping_threads
= NOT_STOPPING_THREADS
;
4072 debug_printf ("stop_all_lwps done, setting stopping_threads "
4073 "back to !stopping\n");
4078 /* Enqueue one signal in the chain of signals which need to be
4079 delivered to this process on next resume. */
4082 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
4084 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
4086 p_sig
->prev
= lwp
->pending_signals
;
4087 p_sig
->signal
= signal
;
4089 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4091 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
4092 lwp
->pending_signals
= p_sig
;
4095 /* Install breakpoints for software single stepping. */
4098 install_software_single_step_breakpoints (struct lwp_info
*lwp
)
4102 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4103 VEC (CORE_ADDR
) *next_pcs
= NULL
;
4104 struct cleanup
*old_chain
= make_cleanup (VEC_cleanup (CORE_ADDR
), &next_pcs
);
4106 next_pcs
= (*the_low_target
.get_next_pcs
) (regcache
);
4108 for (i
= 0; VEC_iterate (CORE_ADDR
, next_pcs
, i
, pc
); ++i
)
4109 set_reinsert_breakpoint (pc
);
4111 do_cleanups (old_chain
);
4114 /* Single step via hardware or software single step.
4115 Return 1 if hardware single stepping, 0 if software single stepping
4116 or can't single step. */
4119 single_step (struct lwp_info
* lwp
)
4123 if (can_hardware_single_step ())
4127 else if (can_software_single_step ())
4129 install_software_single_step_breakpoints (lwp
);
4135 debug_printf ("stepping is not implemented on this target");
4141 /* The signal can be delivered to the inferior if we are not trying to
4142 finish a fast tracepoint collect. Since signal can be delivered in
4143 the step-over, the program may go to signal handler and trap again
4144 after return from the signal handler. We can live with the spurious
4148 lwp_signal_can_be_delivered (struct lwp_info
*lwp
)
4150 return !lwp
->collecting_fast_tracepoint
;
4153 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
4154 SIGNAL is nonzero, give it that signal. */
4157 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
4158 int step
, int signal
, siginfo_t
*info
)
4160 struct thread_info
*thread
= get_lwp_thread (lwp
);
4161 struct thread_info
*saved_thread
;
4162 int fast_tp_collecting
;
4164 struct process_info
*proc
= get_thread_process (thread
);
4166 /* Note that target description may not be initialised
4167 (proc->tdesc == NULL) at this point because the program hasn't
4168 stopped at the first instruction yet. It means GDBserver skips
4169 the extra traps from the wrapper program (see option --wrapper).
4170 Code in this function that requires register access should be
4171 guarded by proc->tdesc == NULL or something else. */
4173 if (lwp
->stopped
== 0)
4176 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
4178 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
4180 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
4182 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4183 user used the "jump" command, or "set $pc = foo"). */
4184 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
4186 /* Collecting 'while-stepping' actions doesn't make sense
4188 release_while_stepping_state_list (thread
);
4191 /* If we have pending signals or status, and a new signal, enqueue the
4192 signal. Also enqueue the signal if it can't be delivered to the
4193 inferior right now. */
4195 && (lwp
->status_pending_p
4196 || lwp
->pending_signals
!= NULL
4197 || !lwp_signal_can_be_delivered (lwp
)))
4199 enqueue_pending_signal (lwp
, signal
, info
);
4201 /* Postpone any pending signal. It was enqueued above. */
4205 if (lwp
->status_pending_p
)
4208 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4209 " has pending status\n",
4210 lwpid_of (thread
), step
? "step" : "continue",
4211 lwp
->stop_expected
? "expected" : "not expected");
4215 saved_thread
= current_thread
;
4216 current_thread
= thread
;
4218 /* This bit needs some thinking about. If we get a signal that
4219 we must report while a single-step reinsert is still pending,
4220 we often end up resuming the thread. It might be better to
4221 (ew) allow a stack of pending events; then we could be sure that
4222 the reinsert happened right away and not lose any signals.
4224 Making this stack would also shrink the window in which breakpoints are
4225 uninserted (see comment in linux_wait_for_lwp) but not enough for
4226 complete correctness, so it won't solve that problem. It may be
4227 worthwhile just to solve this one, however. */
4228 if (lwp
->bp_reinsert
!= 0)
4231 debug_printf (" pending reinsert at 0x%s\n",
4232 paddress (lwp
->bp_reinsert
));
4234 if (can_hardware_single_step ())
4236 if (fast_tp_collecting
== 0)
4239 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
4241 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
4246 step
= maybe_hw_step (thread
);
4250 /* If the thread isn't doing step-over, there shouldn't be any
4251 reinsert breakpoints. */
4252 gdb_assert (!has_reinsert_breakpoints (proc
));
4255 if (fast_tp_collecting
== 1)
4258 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4259 " (exit-jump-pad-bkpt)\n",
4262 else if (fast_tp_collecting
== 2)
4265 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4266 " single-stepping\n",
4269 if (can_hardware_single_step ())
4273 internal_error (__FILE__
, __LINE__
,
4274 "moving out of jump pad single-stepping"
4275 " not implemented on this target");
4279 /* If we have while-stepping actions in this thread set it stepping.
4280 If we have a signal to deliver, it may or may not be set to
4281 SIG_IGN, we don't know. Assume so, and allow collecting
4282 while-stepping into a signal handler. A possible smart thing to
4283 do would be to set an internal breakpoint at the signal return
4284 address, continue, and carry on catching this while-stepping
4285 action only when that breakpoint is hit. A future
4287 if (thread
->while_stepping
!= NULL
)
4290 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4293 step
= single_step (lwp
);
4296 if (proc
->tdesc
!= NULL
&& the_low_target
.get_pc
!= NULL
)
4298 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4300 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
4304 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4305 (long) lwp
->stop_pc
);
4309 /* If we have pending signals, consume one if it can be delivered to
4311 if (lwp
->pending_signals
!= NULL
&& lwp_signal_can_be_delivered (lwp
))
4313 struct pending_signals
**p_sig
;
4315 p_sig
= &lwp
->pending_signals
;
4316 while ((*p_sig
)->prev
!= NULL
)
4317 p_sig
= &(*p_sig
)->prev
;
4319 signal
= (*p_sig
)->signal
;
4320 if ((*p_sig
)->info
.si_signo
!= 0)
4321 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4329 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4330 lwpid_of (thread
), step
? "step" : "continue", signal
,
4331 lwp
->stop_expected
? "expected" : "not expected");
4333 if (the_low_target
.prepare_to_resume
!= NULL
)
4334 the_low_target
.prepare_to_resume (lwp
);
4336 regcache_invalidate_thread (thread
);
4338 lwp
->stepping
= step
;
4340 ptrace_request
= PTRACE_SINGLESTEP
;
4341 else if (gdb_catching_syscalls_p (lwp
))
4342 ptrace_request
= PTRACE_SYSCALL
;
4344 ptrace_request
= PTRACE_CONT
;
4345 ptrace (ptrace_request
,
4347 (PTRACE_TYPE_ARG3
) 0,
4348 /* Coerce to a uintptr_t first to avoid potential gcc warning
4349 of coercing an 8 byte integer to a 4 byte pointer. */
4350 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4352 current_thread
= saved_thread
;
4354 perror_with_name ("resuming thread");
4356 /* Successfully resumed. Clear state that no longer makes sense,
4357 and mark the LWP as running. Must not do this before resuming
4358 otherwise if that fails other code will be confused. E.g., we'd
4359 later try to stop the LWP and hang forever waiting for a stop
4360 status. Note that we must not throw after this is cleared,
4361 otherwise handle_zombie_lwp_error would get confused. */
4363 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4366 /* Called when we try to resume a stopped LWP and that errors out. If
4367 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4368 or about to become), discard the error, clear any pending status
4369 the LWP may have, and return true (we'll collect the exit status
4370 soon enough). Otherwise, return false. */
4373 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4375 struct thread_info
*thread
= get_lwp_thread (lp
);
4377 /* If we get an error after resuming the LWP successfully, we'd
4378 confuse !T state for the LWP being gone. */
4379 gdb_assert (lp
->stopped
);
4381 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4382 because even if ptrace failed with ESRCH, the tracee may be "not
4383 yet fully dead", but already refusing ptrace requests. In that
4384 case the tracee has 'R (Running)' state for a little bit
4385 (observed in Linux 3.18). See also the note on ESRCH in the
4386 ptrace(2) man page. Instead, check whether the LWP has any state
4387 other than ptrace-stopped. */
4389 /* Don't assume anything if /proc/PID/status can't be read. */
4390 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4392 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4393 lp
->status_pending_p
= 0;
4399 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4400 disappears while we try to resume it. */
4403 linux_resume_one_lwp (struct lwp_info
*lwp
,
4404 int step
, int signal
, siginfo_t
*info
)
4408 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
4410 CATCH (ex
, RETURN_MASK_ERROR
)
4412 if (!check_ptrace_stopped_lwp_gone (lwp
))
4413 throw_exception (ex
);
4418 struct thread_resume_array
4420 struct thread_resume
*resume
;
4424 /* This function is called once per thread via find_inferior.
4425 ARG is a pointer to a thread_resume_array struct.
4426 We look up the thread specified by ENTRY in ARG, and mark the thread
4427 with a pointer to the appropriate resume request.
4429 This algorithm is O(threads * resume elements), but resume elements
4430 is small (and will remain small at least until GDB supports thread
4434 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
4436 struct thread_info
*thread
= (struct thread_info
*) entry
;
4437 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4439 struct thread_resume_array
*r
;
4441 r
= (struct thread_resume_array
*) arg
;
4443 for (ndx
= 0; ndx
< r
->n
; ndx
++)
4445 ptid_t ptid
= r
->resume
[ndx
].thread
;
4446 if (ptid_equal (ptid
, minus_one_ptid
)
4447 || ptid_equal (ptid
, entry
->id
)
4448 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4450 || (ptid_get_pid (ptid
) == pid_of (thread
)
4451 && (ptid_is_pid (ptid
)
4452 || ptid_get_lwp (ptid
) == -1)))
4454 if (r
->resume
[ndx
].kind
== resume_stop
4455 && thread
->last_resume_kind
== resume_stop
)
4458 debug_printf ("already %s LWP %ld at GDB's request\n",
4459 (thread
->last_status
.kind
4460 == TARGET_WAITKIND_STOPPED
)
4468 lwp
->resume
= &r
->resume
[ndx
];
4469 thread
->last_resume_kind
= lwp
->resume
->kind
;
4471 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4472 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4474 /* If we had a deferred signal to report, dequeue one now.
4475 This can happen if LWP gets more than one signal while
4476 trying to get out of a jump pad. */
4478 && !lwp
->status_pending_p
4479 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4481 lwp
->status_pending_p
= 1;
4484 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4485 "leaving status pending.\n",
4486 WSTOPSIG (lwp
->status_pending
),
4494 /* No resume action for this thread. */
4500 /* find_inferior callback for linux_resume.
4501 Set *FLAG_P if this lwp has an interesting status pending. */
4504 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
4506 struct thread_info
*thread
= (struct thread_info
*) entry
;
4507 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4509 /* LWPs which will not be resumed are not interesting, because
4510 we might not wait for them next time through linux_wait. */
4511 if (lwp
->resume
== NULL
)
4514 if (thread_still_has_status_pending_p (thread
))
4515 * (int *) flag_p
= 1;
4520 /* Return 1 if this lwp that GDB wants running is stopped at an
4521 internal breakpoint that we need to step over. It assumes that any
4522 required STOP_PC adjustment has already been propagated to the
4523 inferior's regcache. */
4526 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
4528 struct thread_info
*thread
= (struct thread_info
*) entry
;
4529 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4530 struct thread_info
*saved_thread
;
4532 struct process_info
*proc
= get_thread_process (thread
);
4534 /* GDBserver is skipping the extra traps from the wrapper program,
4535 don't have to do step over. */
4536 if (proc
->tdesc
== NULL
)
4539 /* LWPs which will not be resumed are not interesting, because we
4540 might not wait for them next time through linux_wait. */
4545 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4550 if (thread
->last_resume_kind
== resume_stop
)
4553 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4559 gdb_assert (lwp
->suspended
>= 0);
4564 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4569 if (lwp
->status_pending_p
)
4572 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4578 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4582 /* If the PC has changed since we stopped, then don't do anything,
4583 and let the breakpoint/tracepoint be hit. This happens if, for
4584 instance, GDB handled the decr_pc_after_break subtraction itself,
4585 GDB is OOL stepping this thread, or the user has issued a "jump"
4586 command, or poked thread's registers herself. */
4587 if (pc
!= lwp
->stop_pc
)
4590 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4591 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4593 paddress (lwp
->stop_pc
), paddress (pc
));
4597 /* On software single step target, resume the inferior with signal
4598 rather than stepping over. */
4599 if (can_software_single_step ()
4600 && lwp
->pending_signals
!= NULL
4601 && lwp_signal_can_be_delivered (lwp
))
4604 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4611 saved_thread
= current_thread
;
4612 current_thread
= thread
;
4614 /* We can only step over breakpoints we know about. */
4615 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4617 /* Don't step over a breakpoint that GDB expects to hit
4618 though. If the condition is being evaluated on the target's side
4619 and it evaluate to false, step over this breakpoint as well. */
4620 if (gdb_breakpoint_here (pc
)
4621 && gdb_condition_true_at_breakpoint (pc
)
4622 && gdb_no_commands_at_breakpoint (pc
))
4625 debug_printf ("Need step over [LWP %ld]? yes, but found"
4626 " GDB breakpoint at 0x%s; skipping step over\n",
4627 lwpid_of (thread
), paddress (pc
));
4629 current_thread
= saved_thread
;
4635 debug_printf ("Need step over [LWP %ld]? yes, "
4636 "found breakpoint at 0x%s\n",
4637 lwpid_of (thread
), paddress (pc
));
4639 /* We've found an lwp that needs stepping over --- return 1 so
4640 that find_inferior stops looking. */
4641 current_thread
= saved_thread
;
4647 current_thread
= saved_thread
;
4650 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4652 lwpid_of (thread
), paddress (pc
));
4657 /* Start a step-over operation on LWP. When LWP stopped at a
4658 breakpoint, to make progress, we need to remove the breakpoint out
4659 of the way. If we let other threads run while we do that, they may
4660 pass by the breakpoint location and miss hitting it. To avoid
4661 that, a step-over momentarily stops all threads while LWP is
4662 single-stepped by either hardware or software while the breakpoint
4663 is temporarily uninserted from the inferior. When the single-step
4664 finishes, we reinsert the breakpoint, and let all threads that are
4665 supposed to be running, run again. */
4668 start_step_over (struct lwp_info
*lwp
)
4670 struct thread_info
*thread
= get_lwp_thread (lwp
);
4671 struct thread_info
*saved_thread
;
4676 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4679 stop_all_lwps (1, lwp
);
4681 if (lwp
->suspended
!= 0)
4683 internal_error (__FILE__
, __LINE__
,
4684 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4689 debug_printf ("Done stopping all threads for step-over.\n");
4691 /* Note, we should always reach here with an already adjusted PC,
4692 either by GDB (if we're resuming due to GDB's request), or by our
4693 caller, if we just finished handling an internal breakpoint GDB
4694 shouldn't care about. */
4697 saved_thread
= current_thread
;
4698 current_thread
= thread
;
4700 lwp
->bp_reinsert
= pc
;
4701 uninsert_breakpoints_at (pc
);
4702 uninsert_fast_tracepoint_jumps_at (pc
);
4704 step
= single_step (lwp
);
4706 current_thread
= saved_thread
;
4708 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4710 /* Require next event from this LWP. */
4711 step_over_bkpt
= thread
->entry
.id
;
4715 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4716 start_step_over, if still there, and delete any reinsert
4717 breakpoints we've set, on non hardware single-step targets. */
4720 finish_step_over (struct lwp_info
*lwp
)
4722 if (lwp
->bp_reinsert
!= 0)
4724 struct thread_info
*saved_thread
= current_thread
;
4727 debug_printf ("Finished step over.\n");
4729 current_thread
= get_lwp_thread (lwp
);
4731 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4732 may be no breakpoint to reinsert there by now. */
4733 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4734 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4736 lwp
->bp_reinsert
= 0;
4738 /* Delete any software-single-step reinsert breakpoints. No
4739 longer needed. We don't have to worry about other threads
4740 hitting this trap, and later not being able to explain it,
4741 because we were stepping over a breakpoint, and we hold all
4742 threads but LWP stopped while doing that. */
4743 if (!can_hardware_single_step ())
4745 gdb_assert (has_reinsert_breakpoints (current_process ()));
4746 delete_reinsert_breakpoints ();
4749 step_over_bkpt
= null_ptid
;
4750 current_thread
= saved_thread
;
4757 /* If there's a step over in progress, wait until all threads stop
4758 (that is, until the stepping thread finishes its step), and
4759 unsuspend all lwps. The stepping thread ends with its status
4760 pending, which is processed later when we get back to processing
4764 complete_ongoing_step_over (void)
4766 if (!ptid_equal (step_over_bkpt
, null_ptid
))
4768 struct lwp_info
*lwp
;
4773 debug_printf ("detach: step over in progress, finish it first\n");
4775 /* Passing NULL_PTID as filter indicates we want all events to
4776 be left pending. Eventually this returns when there are no
4777 unwaited-for children left. */
4778 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4780 gdb_assert (ret
== -1);
4782 lwp
= find_lwp_pid (step_over_bkpt
);
4784 finish_step_over (lwp
);
4785 step_over_bkpt
= null_ptid
;
4786 unsuspend_all_lwps (lwp
);
4790 /* This function is called once per thread. We check the thread's resume
4791 request, which will tell us whether to resume, step, or leave the thread
4792 stopped; and what signal, if any, it should be sent.
4794 For threads which we aren't explicitly told otherwise, we preserve
4795 the stepping flag; this is used for stepping over gdbserver-placed
4798 If pending_flags was set in any thread, we queue any needed
4799 signals, since we won't actually resume. We already have a pending
4800 event to report, so we don't need to preserve any step requests;
4801 they should be re-issued if necessary. */
4804 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
4806 struct thread_info
*thread
= (struct thread_info
*) entry
;
4807 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4809 int leave_all_stopped
= * (int *) arg
;
4812 if (lwp
->resume
== NULL
)
4815 if (lwp
->resume
->kind
== resume_stop
)
4818 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4823 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4825 /* Stop the thread, and wait for the event asynchronously,
4826 through the event loop. */
4832 debug_printf ("already stopped LWP %ld\n",
4835 /* The LWP may have been stopped in an internal event that
4836 was not meant to be notified back to GDB (e.g., gdbserver
4837 breakpoint), so we should be reporting a stop event in
4840 /* If the thread already has a pending SIGSTOP, this is a
4841 no-op. Otherwise, something later will presumably resume
4842 the thread and this will cause it to cancel any pending
4843 operation, due to last_resume_kind == resume_stop. If
4844 the thread already has a pending status to report, we
4845 will still report it the next time we wait - see
4846 status_pending_p_callback. */
4848 /* If we already have a pending signal to report, then
4849 there's no need to queue a SIGSTOP, as this means we're
4850 midway through moving the LWP out of the jumppad, and we
4851 will report the pending signal as soon as that is
4853 if (lwp
->pending_signals_to_report
== NULL
)
4857 /* For stop requests, we're done. */
4859 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4863 /* If this thread which is about to be resumed has a pending status,
4864 then don't resume it - we can just report the pending status.
4865 Likewise if it is suspended, because e.g., another thread is
4866 stepping past a breakpoint. Make sure to queue any signals that
4867 would otherwise be sent. In all-stop mode, we do this decision
4868 based on if *any* thread has a pending status. If there's a
4869 thread that needs the step-over-breakpoint dance, then don't
4870 resume any other thread but that particular one. */
4871 leave_pending
= (lwp
->suspended
4872 || lwp
->status_pending_p
4873 || leave_all_stopped
);
4878 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4880 step
= (lwp
->resume
->kind
== resume_step
);
4881 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
4886 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4888 /* If we have a new signal, enqueue the signal. */
4889 if (lwp
->resume
->sig
!= 0)
4891 struct pending_signals
*p_sig
= XCNEW (struct pending_signals
);
4893 p_sig
->prev
= lwp
->pending_signals
;
4894 p_sig
->signal
= lwp
->resume
->sig
;
4896 /* If this is the same signal we were previously stopped by,
4897 make sure to queue its siginfo. We can ignore the return
4898 value of ptrace; if it fails, we'll skip
4899 PTRACE_SETSIGINFO. */
4900 if (WIFSTOPPED (lwp
->last_status
)
4901 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
4902 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4905 lwp
->pending_signals
= p_sig
;
4909 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4915 linux_resume (struct thread_resume
*resume_info
, size_t n
)
4917 struct thread_resume_array array
= { resume_info
, n
};
4918 struct thread_info
*need_step_over
= NULL
;
4920 int leave_all_stopped
;
4925 debug_printf ("linux_resume:\n");
4928 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
4930 /* If there is a thread which would otherwise be resumed, which has
4931 a pending status, then don't resume any threads - we can just
4932 report the pending status. Make sure to queue any signals that
4933 would otherwise be sent. In non-stop mode, we'll apply this
4934 logic to each thread individually. We consume all pending events
4935 before considering to start a step-over (in all-stop). */
4938 find_inferior (&all_threads
, resume_status_pending_p
, &any_pending
);
4940 /* If there is a thread which would otherwise be resumed, which is
4941 stopped at a breakpoint that needs stepping over, then don't
4942 resume any threads - have it step over the breakpoint with all
4943 other threads stopped, then resume all threads again. Make sure
4944 to queue any signals that would otherwise be delivered or
4946 if (!any_pending
&& supports_breakpoints ())
4948 = (struct thread_info
*) find_inferior (&all_threads
,
4949 need_step_over_p
, NULL
);
4951 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4955 if (need_step_over
!= NULL
)
4956 debug_printf ("Not resuming all, need step over\n");
4957 else if (any_pending
)
4958 debug_printf ("Not resuming, all-stop and found "
4959 "an LWP with pending status\n");
4961 debug_printf ("Resuming, no pending status or step over needed\n");
4964 /* Even if we're leaving threads stopped, queue all signals we'd
4965 otherwise deliver. */
4966 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
4969 start_step_over (get_thread_lwp (need_step_over
));
4973 debug_printf ("linux_resume done\n");
4977 /* We may have events that were pending that can/should be sent to
4978 the client now. Trigger a linux_wait call. */
4979 if (target_is_async_p ())
4983 /* This function is called once per thread. We check the thread's
4984 last resume request, which will tell us whether to resume, step, or
4985 leave the thread stopped. Any signal the client requested to be
4986 delivered has already been enqueued at this point.
4988 If any thread that GDB wants running is stopped at an internal
4989 breakpoint that needs stepping over, we start a step-over operation
4990 on that particular thread, and leave all others stopped. */
4993 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4995 struct thread_info
*thread
= (struct thread_info
*) entry
;
4996 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5003 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
5008 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
5012 if (thread
->last_resume_kind
== resume_stop
5013 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
5016 debug_printf (" client wants LWP to remain %ld stopped\n",
5021 if (lwp
->status_pending_p
)
5024 debug_printf (" LWP %ld has pending status, leaving stopped\n",
5029 gdb_assert (lwp
->suspended
>= 0);
5034 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
5038 if (thread
->last_resume_kind
== resume_stop
5039 && lwp
->pending_signals_to_report
== NULL
5040 && lwp
->collecting_fast_tracepoint
== 0)
5042 /* We haven't reported this LWP as stopped yet (otherwise, the
5043 last_status.kind check above would catch it, and we wouldn't
5044 reach here. This LWP may have been momentarily paused by a
5045 stop_all_lwps call while handling for example, another LWP's
5046 step-over. In that case, the pending expected SIGSTOP signal
5047 that was queued at vCont;t handling time will have already
5048 been consumed by wait_for_sigstop, and so we need to requeue
5049 another one here. Note that if the LWP already has a SIGSTOP
5050 pending, this is a no-op. */
5053 debug_printf ("Client wants LWP %ld to stop. "
5054 "Making sure it has a SIGSTOP pending\n",
5060 if (thread
->last_resume_kind
== resume_step
)
5063 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5067 else if (lwp
->bp_reinsert
!= 0)
5070 debug_printf (" stepping LWP %ld, reinsert set\n",
5073 step
= maybe_hw_step (thread
);
5078 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
5083 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
5085 struct thread_info
*thread
= (struct thread_info
*) entry
;
5086 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5091 lwp_suspended_decr (lwp
);
5093 return proceed_one_lwp (entry
, except
);
5096 /* When we finish a step-over, set threads running again. If there's
5097 another thread that may need a step-over, now's the time to start
5098 it. Eventually, we'll move all threads past their breakpoints. */
5101 proceed_all_lwps (void)
5103 struct thread_info
*need_step_over
;
5105 /* If there is a thread which would otherwise be resumed, which is
5106 stopped at a breakpoint that needs stepping over, then don't
5107 resume any threads - have it step over the breakpoint with all
5108 other threads stopped, then resume all threads again. */
5110 if (supports_breakpoints ())
5113 = (struct thread_info
*) find_inferior (&all_threads
,
5114 need_step_over_p
, NULL
);
5116 if (need_step_over
!= NULL
)
5119 debug_printf ("proceed_all_lwps: found "
5120 "thread %ld needing a step-over\n",
5121 lwpid_of (need_step_over
));
5123 start_step_over (get_thread_lwp (need_step_over
));
5129 debug_printf ("Proceeding, no step-over needed\n");
5131 find_inferior (&all_threads
, proceed_one_lwp
, NULL
);
5134 /* Stopped LWPs that the client wanted to be running, that don't have
5135 pending statuses, are set to run again, except for EXCEPT, if not
5136 NULL. This undoes a stop_all_lwps call. */
5139 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
5145 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5146 lwpid_of (get_lwp_thread (except
)));
5148 debug_printf ("unstopping all lwps\n");
5152 find_inferior (&all_threads
, unsuspend_and_proceed_one_lwp
, except
);
5154 find_inferior (&all_threads
, proceed_one_lwp
, except
);
5158 debug_printf ("unstop_all_lwps done\n");
5164 #ifdef HAVE_LINUX_REGSETS
5166 #define use_linux_regsets 1
5168 /* Returns true if REGSET has been disabled. */
5171 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
5173 return (info
->disabled_regsets
!= NULL
5174 && info
->disabled_regsets
[regset
- info
->regsets
]);
5177 /* Disable REGSET. */
5180 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5184 dr_offset
= regset
- info
->regsets
;
5185 if (info
->disabled_regsets
== NULL
)
5186 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5187 info
->disabled_regsets
[dr_offset
] = 1;
5191 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5192 struct regcache
*regcache
)
5194 struct regset_info
*regset
;
5195 int saw_general_regs
= 0;
5199 pid
= lwpid_of (current_thread
);
5200 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5205 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5208 buf
= xmalloc (regset
->size
);
5210 nt_type
= regset
->nt_type
;
5214 iov
.iov_len
= regset
->size
;
5215 data
= (void *) &iov
;
5221 res
= ptrace (regset
->get_request
, pid
,
5222 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5224 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5230 /* If we get EIO on a regset, do not try it again for
5231 this process mode. */
5232 disable_regset (regsets_info
, regset
);
5234 else if (errno
== ENODATA
)
5236 /* ENODATA may be returned if the regset is currently
5237 not "active". This can happen in normal operation,
5238 so suppress the warning in this case. */
5243 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5250 if (regset
->type
== GENERAL_REGS
)
5251 saw_general_regs
= 1;
5252 regset
->store_function (regcache
, buf
);
5256 if (saw_general_regs
)
5263 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5264 struct regcache
*regcache
)
5266 struct regset_info
*regset
;
5267 int saw_general_regs
= 0;
5271 pid
= lwpid_of (current_thread
);
5272 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5277 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5278 || regset
->fill_function
== NULL
)
5281 buf
= xmalloc (regset
->size
);
5283 /* First fill the buffer with the current register set contents,
5284 in case there are any items in the kernel's regset that are
5285 not in gdbserver's regcache. */
5287 nt_type
= regset
->nt_type
;
5291 iov
.iov_len
= regset
->size
;
5292 data
= (void *) &iov
;
5298 res
= ptrace (regset
->get_request
, pid
,
5299 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5301 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5306 /* Then overlay our cached registers on that. */
5307 regset
->fill_function (regcache
, buf
);
5309 /* Only now do we write the register set. */
5311 res
= ptrace (regset
->set_request
, pid
,
5312 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5314 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5322 /* If we get EIO on a regset, do not try it again for
5323 this process mode. */
5324 disable_regset (regsets_info
, regset
);
5326 else if (errno
== ESRCH
)
5328 /* At this point, ESRCH should mean the process is
5329 already gone, in which case we simply ignore attempts
5330 to change its registers. See also the related
5331 comment in linux_resume_one_lwp. */
5337 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5340 else if (regset
->type
== GENERAL_REGS
)
5341 saw_general_regs
= 1;
5344 if (saw_general_regs
)
5350 #else /* !HAVE_LINUX_REGSETS */
5352 #define use_linux_regsets 0
5353 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5354 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5358 /* Return 1 if register REGNO is supported by one of the regset ptrace
5359 calls or 0 if it has to be transferred individually. */
5362 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5364 unsigned char mask
= 1 << (regno
% 8);
5365 size_t index
= regno
/ 8;
5367 return (use_linux_regsets
5368 && (regs_info
->regset_bitmap
== NULL
5369 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5372 #ifdef HAVE_LINUX_USRREGS
5375 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5379 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5380 error ("Invalid register number %d.", regnum
);
5382 addr
= usrregs
->regmap
[regnum
];
5387 /* Fetch one register. */
5389 fetch_register (const struct usrregs_info
*usrregs
,
5390 struct regcache
*regcache
, int regno
)
5397 if (regno
>= usrregs
->num_regs
)
5399 if ((*the_low_target
.cannot_fetch_register
) (regno
))
5402 regaddr
= register_addr (usrregs
, regno
);
5406 size
= ((register_size (regcache
->tdesc
, regno
)
5407 + sizeof (PTRACE_XFER_TYPE
) - 1)
5408 & -sizeof (PTRACE_XFER_TYPE
));
5409 buf
= (char *) alloca (size
);
5411 pid
= lwpid_of (current_thread
);
5412 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5415 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5416 ptrace (PTRACE_PEEKUSER
, pid
,
5417 /* Coerce to a uintptr_t first to avoid potential gcc warning
5418 of coercing an 8 byte integer to a 4 byte pointer. */
5419 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5420 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5422 error ("reading register %d: %s", regno
, strerror (errno
));
5425 if (the_low_target
.supply_ptrace_register
)
5426 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
5428 supply_register (regcache
, regno
, buf
);
5431 /* Store one register. */
5433 store_register (const struct usrregs_info
*usrregs
,
5434 struct regcache
*regcache
, int regno
)
5441 if (regno
>= usrregs
->num_regs
)
5443 if ((*the_low_target
.cannot_store_register
) (regno
))
5446 regaddr
= register_addr (usrregs
, regno
);
5450 size
= ((register_size (regcache
->tdesc
, regno
)
5451 + sizeof (PTRACE_XFER_TYPE
) - 1)
5452 & -sizeof (PTRACE_XFER_TYPE
));
5453 buf
= (char *) alloca (size
);
5454 memset (buf
, 0, size
);
5456 if (the_low_target
.collect_ptrace_register
)
5457 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
5459 collect_register (regcache
, regno
, buf
);
5461 pid
= lwpid_of (current_thread
);
5462 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5465 ptrace (PTRACE_POKEUSER
, pid
,
5466 /* Coerce to a uintptr_t first to avoid potential gcc warning
5467 about coercing an 8 byte integer to a 4 byte pointer. */
5468 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5469 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5472 /* At this point, ESRCH should mean the process is
5473 already gone, in which case we simply ignore attempts
5474 to change its registers. See also the related
5475 comment in linux_resume_one_lwp. */
5479 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
5480 error ("writing register %d: %s", regno
, strerror (errno
));
5482 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5486 /* Fetch all registers, or just one, from the child process.
5487 If REGNO is -1, do this for all registers, skipping any that are
5488 assumed to have been retrieved by regsets_fetch_inferior_registers,
5489 unless ALL is non-zero.
5490 Otherwise, REGNO specifies which register (so we can save time). */
5492 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
5493 struct regcache
*regcache
, int regno
, int all
)
5495 struct usrregs_info
*usr
= regs_info
->usrregs
;
5499 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5500 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5501 fetch_register (usr
, regcache
, regno
);
5504 fetch_register (usr
, regcache
, regno
);
5507 /* Store our register values back into the inferior.
5508 If REGNO is -1, do this for all registers, skipping any that are
5509 assumed to have been saved by regsets_store_inferior_registers,
5510 unless ALL is non-zero.
5511 Otherwise, REGNO specifies which register (so we can save time). */
5513 usr_store_inferior_registers (const struct regs_info
*regs_info
,
5514 struct regcache
*regcache
, int regno
, int all
)
5516 struct usrregs_info
*usr
= regs_info
->usrregs
;
5520 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5521 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5522 store_register (usr
, regcache
, regno
);
5525 store_register (usr
, regcache
, regno
);
5528 #else /* !HAVE_LINUX_USRREGS */
5530 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5531 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5537 linux_fetch_registers (struct regcache
*regcache
, int regno
)
5541 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5545 if (the_low_target
.fetch_register
!= NULL
5546 && regs_info
->usrregs
!= NULL
)
5547 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5548 (*the_low_target
.fetch_register
) (regcache
, regno
);
5550 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5551 if (regs_info
->usrregs
!= NULL
)
5552 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5556 if (the_low_target
.fetch_register
!= NULL
5557 && (*the_low_target
.fetch_register
) (regcache
, regno
))
5560 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5562 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5564 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5565 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5570 linux_store_registers (struct regcache
*regcache
, int regno
)
5574 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5578 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5580 if (regs_info
->usrregs
!= NULL
)
5581 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5585 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5587 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5589 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5590 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5595 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5596 to debugger memory starting at MYADDR. */
5599 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5601 int pid
= lwpid_of (current_thread
);
5602 register PTRACE_XFER_TYPE
*buffer
;
5603 register CORE_ADDR addr
;
5610 /* Try using /proc. Don't bother for one word. */
5611 if (len
>= 3 * sizeof (long))
5615 /* We could keep this file open and cache it - possibly one per
5616 thread. That requires some juggling, but is even faster. */
5617 sprintf (filename
, "/proc/%d/mem", pid
);
5618 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5622 /* If pread64 is available, use it. It's faster if the kernel
5623 supports it (only one syscall), and it's 64-bit safe even on
5624 32-bit platforms (for instance, SPARC debugging a SPARC64
5627 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5630 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5631 bytes
= read (fd
, myaddr
, len
);
5638 /* Some data was read, we'll try to get the rest with ptrace. */
5648 /* Round starting address down to longword boundary. */
5649 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5650 /* Round ending address up; get number of longwords that makes. */
5651 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5652 / sizeof (PTRACE_XFER_TYPE
));
5653 /* Allocate buffer of that many longwords. */
5654 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5656 /* Read all the longwords */
5658 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5660 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5661 about coercing an 8 byte integer to a 4 byte pointer. */
5662 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5663 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5664 (PTRACE_TYPE_ARG4
) 0);
5670 /* Copy appropriate bytes out of the buffer. */
5673 i
*= sizeof (PTRACE_XFER_TYPE
);
5674 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5676 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5683 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5684 memory at MEMADDR. On failure (cannot write to the inferior)
5685 returns the value of errno. Always succeeds if LEN is zero. */
5688 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5691 /* Round starting address down to longword boundary. */
5692 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5693 /* Round ending address up; get number of longwords that makes. */
5695 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5696 / sizeof (PTRACE_XFER_TYPE
);
5698 /* Allocate buffer of that many longwords. */
5699 register PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5701 int pid
= lwpid_of (current_thread
);
5705 /* Zero length write always succeeds. */
5711 /* Dump up to four bytes. */
5712 char str
[4 * 2 + 1];
5714 int dump
= len
< 4 ? len
: 4;
5716 for (i
= 0; i
< dump
; i
++)
5718 sprintf (p
, "%02x", myaddr
[i
]);
5723 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5724 str
, (long) memaddr
, pid
);
5727 /* Fill start and end extra bytes of buffer with existing memory data. */
5730 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5731 about coercing an 8 byte integer to a 4 byte pointer. */
5732 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5733 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5734 (PTRACE_TYPE_ARG4
) 0);
5742 = ptrace (PTRACE_PEEKTEXT
, pid
,
5743 /* Coerce to a uintptr_t first to avoid potential gcc warning
5744 about coercing an 8 byte integer to a 4 byte pointer. */
5745 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5746 * sizeof (PTRACE_XFER_TYPE
)),
5747 (PTRACE_TYPE_ARG4
) 0);
5752 /* Copy data to be written over corresponding part of buffer. */
5754 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5757 /* Write the entire buffer. */
5759 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5762 ptrace (PTRACE_POKETEXT
, pid
,
5763 /* Coerce to a uintptr_t first to avoid potential gcc warning
5764 about coercing an 8 byte integer to a 4 byte pointer. */
5765 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5766 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5775 linux_look_up_symbols (void)
5777 #ifdef USE_THREAD_DB
5778 struct process_info
*proc
= current_process ();
5780 if (proc
->priv
->thread_db
!= NULL
)
5788 linux_request_interrupt (void)
5790 extern unsigned long signal_pid
;
5792 /* Send a SIGINT to the process group. This acts just like the user
5793 typed a ^C on the controlling terminal. */
5794 kill (-signal_pid
, SIGINT
);
5797 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5798 to debugger memory starting at MYADDR. */
5801 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5803 char filename
[PATH_MAX
];
5805 int pid
= lwpid_of (current_thread
);
5807 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5809 fd
= open (filename
, O_RDONLY
);
5813 if (offset
!= (CORE_ADDR
) 0
5814 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5817 n
= read (fd
, myaddr
, len
);
5824 /* These breakpoint and watchpoint related wrapper functions simply
5825 pass on the function call if the target has registered a
5826 corresponding function. */
5829 linux_supports_z_point_type (char z_type
)
5831 return (the_low_target
.supports_z_point_type
!= NULL
5832 && the_low_target
.supports_z_point_type (z_type
));
5836 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5837 int size
, struct raw_breakpoint
*bp
)
5839 if (type
== raw_bkpt_type_sw
)
5840 return insert_memory_breakpoint (bp
);
5841 else if (the_low_target
.insert_point
!= NULL
)
5842 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5844 /* Unsupported (see target.h). */
5849 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5850 int size
, struct raw_breakpoint
*bp
)
5852 if (type
== raw_bkpt_type_sw
)
5853 return remove_memory_breakpoint (bp
);
5854 else if (the_low_target
.remove_point
!= NULL
)
5855 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5857 /* Unsupported (see target.h). */
5861 /* Implement the to_stopped_by_sw_breakpoint target_ops
5865 linux_stopped_by_sw_breakpoint (void)
5867 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5869 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5872 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5876 linux_supports_stopped_by_sw_breakpoint (void)
5878 return USE_SIGTRAP_SIGINFO
;
5881 /* Implement the to_stopped_by_hw_breakpoint target_ops
5885 linux_stopped_by_hw_breakpoint (void)
5887 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5889 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5892 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5896 linux_supports_stopped_by_hw_breakpoint (void)
5898 return USE_SIGTRAP_SIGINFO
;
5901 /* Implement the supports_hardware_single_step target_ops method. */
5904 linux_supports_hardware_single_step (void)
5906 return can_hardware_single_step ();
5910 linux_supports_software_single_step (void)
5912 return can_software_single_step ();
5916 linux_stopped_by_watchpoint (void)
5918 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5920 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5924 linux_stopped_data_address (void)
5926 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5928 return lwp
->stopped_data_address
;
5931 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5932 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5933 && defined(PT_TEXT_END_ADDR)
5935 /* This is only used for targets that define PT_TEXT_ADDR,
5936 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5937 the target has different ways of acquiring this information, like
5940 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5941 to tell gdb about. */
5944 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5946 unsigned long text
, text_end
, data
;
5947 int pid
= lwpid_of (current_thread
);
5951 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5952 (PTRACE_TYPE_ARG4
) 0);
5953 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5954 (PTRACE_TYPE_ARG4
) 0);
5955 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5956 (PTRACE_TYPE_ARG4
) 0);
5960 /* Both text and data offsets produced at compile-time (and so
5961 used by gdb) are relative to the beginning of the program,
5962 with the data segment immediately following the text segment.
5963 However, the actual runtime layout in memory may put the data
5964 somewhere else, so when we send gdb a data base-address, we
5965 use the real data base address and subtract the compile-time
5966 data base-address from it (which is just the length of the
5967 text segment). BSS immediately follows data in both
5970 *data_p
= data
- (text_end
- text
);
5979 linux_qxfer_osdata (const char *annex
,
5980 unsigned char *readbuf
, unsigned const char *writebuf
,
5981 CORE_ADDR offset
, int len
)
5983 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5986 /* Convert a native/host siginfo object, into/from the siginfo in the
5987 layout of the inferiors' architecture. */
5990 siginfo_fixup (siginfo_t
*siginfo
, gdb_byte
*inf_siginfo
, int direction
)
5994 if (the_low_target
.siginfo_fixup
!= NULL
)
5995 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5997 /* If there was no callback, or the callback didn't do anything,
5998 then just do a straight memcpy. */
6002 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
6004 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
6009 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
6010 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
6014 gdb_byte inf_siginfo
[sizeof (siginfo_t
)];
6016 if (current_thread
== NULL
)
6019 pid
= lwpid_of (current_thread
);
6022 debug_printf ("%s siginfo for lwp %d.\n",
6023 readbuf
!= NULL
? "Reading" : "Writing",
6026 if (offset
>= sizeof (siginfo
))
6029 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6032 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6033 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6034 inferior with a 64-bit GDBSERVER should look the same as debugging it
6035 with a 32-bit GDBSERVER, we need to convert it. */
6036 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
6038 if (offset
+ len
> sizeof (siginfo
))
6039 len
= sizeof (siginfo
) - offset
;
6041 if (readbuf
!= NULL
)
6042 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
6045 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
6047 /* Convert back to ptrace layout before flushing it out. */
6048 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
6050 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6057 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6058 so we notice when children change state; as the handler for the
6059 sigsuspend in my_waitpid. */
6062 sigchld_handler (int signo
)
6064 int old_errno
= errno
;
6070 /* fprintf is not async-signal-safe, so call write
6072 if (write (2, "sigchld_handler\n",
6073 sizeof ("sigchld_handler\n") - 1) < 0)
6074 break; /* just ignore */
6078 if (target_is_async_p ())
6079 async_file_mark (); /* trigger a linux_wait */
6085 linux_supports_non_stop (void)
6091 linux_async (int enable
)
6093 int previous
= target_is_async_p ();
6096 debug_printf ("linux_async (%d), previous=%d\n",
6099 if (previous
!= enable
)
6102 sigemptyset (&mask
);
6103 sigaddset (&mask
, SIGCHLD
);
6105 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
6109 if (pipe (linux_event_pipe
) == -1)
6111 linux_event_pipe
[0] = -1;
6112 linux_event_pipe
[1] = -1;
6113 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6115 warning ("creating event pipe failed.");
6119 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
6120 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
6122 /* Register the event loop handler. */
6123 add_file_handler (linux_event_pipe
[0],
6124 handle_target_event
, NULL
);
6126 /* Always trigger a linux_wait. */
6131 delete_file_handler (linux_event_pipe
[0]);
6133 close (linux_event_pipe
[0]);
6134 close (linux_event_pipe
[1]);
6135 linux_event_pipe
[0] = -1;
6136 linux_event_pipe
[1] = -1;
6139 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6146 linux_start_non_stop (int nonstop
)
6148 /* Register or unregister from event-loop accordingly. */
6149 linux_async (nonstop
);
6151 if (target_is_async_p () != (nonstop
!= 0))
6158 linux_supports_multi_process (void)
6163 /* Check if fork events are supported. */
6166 linux_supports_fork_events (void)
6168 return linux_supports_tracefork ();
6171 /* Check if vfork events are supported. */
6174 linux_supports_vfork_events (void)
6176 return linux_supports_tracefork ();
6179 /* Check if exec events are supported. */
6182 linux_supports_exec_events (void)
6184 return linux_supports_traceexec ();
6187 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
6188 options for the specified lwp. */
6191 reset_lwp_ptrace_options_callback (struct inferior_list_entry
*entry
,
6194 struct thread_info
*thread
= (struct thread_info
*) entry
;
6195 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6199 /* Stop the lwp so we can modify its ptrace options. */
6200 lwp
->must_set_ptrace_flags
= 1;
6201 linux_stop_lwp (lwp
);
6205 /* Already stopped; go ahead and set the ptrace options. */
6206 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6207 int options
= linux_low_ptrace_options (proc
->attached
);
6209 linux_enable_event_reporting (lwpid_of (thread
), options
);
6210 lwp
->must_set_ptrace_flags
= 0;
6216 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6217 ptrace flags for all inferiors. This is in case the new GDB connection
6218 doesn't support the same set of events that the previous one did. */
6221 linux_handle_new_gdb_connection (void)
6225 /* Request that all the lwps reset their ptrace options. */
6226 find_inferior (&all_threads
, reset_lwp_ptrace_options_callback
, &pid
);
6230 linux_supports_disable_randomization (void)
6232 #ifdef HAVE_PERSONALITY
6240 linux_supports_agent (void)
6246 linux_supports_range_stepping (void)
6248 if (*the_low_target
.supports_range_stepping
== NULL
)
6251 return (*the_low_target
.supports_range_stepping
) ();
6254 /* Enumerate spufs IDs for process PID. */
6256 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
6262 struct dirent
*entry
;
6264 sprintf (path
, "/proc/%ld/fd", pid
);
6265 dir
= opendir (path
);
6270 while ((entry
= readdir (dir
)) != NULL
)
6276 fd
= atoi (entry
->d_name
);
6280 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
6281 if (stat (path
, &st
) != 0)
6283 if (!S_ISDIR (st
.st_mode
))
6286 if (statfs (path
, &stfs
) != 0)
6288 if (stfs
.f_type
!= SPUFS_MAGIC
)
6291 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
6293 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
6303 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6304 object type, using the /proc file system. */
6306 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
6307 unsigned const char *writebuf
,
6308 CORE_ADDR offset
, int len
)
6310 long pid
= lwpid_of (current_thread
);
6315 if (!writebuf
&& !readbuf
)
6323 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
6326 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
6327 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
6332 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
6339 ret
= write (fd
, writebuf
, (size_t) len
);
6341 ret
= read (fd
, readbuf
, (size_t) len
);
6347 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6348 struct target_loadseg
6350 /* Core address to which the segment is mapped. */
6352 /* VMA recorded in the program header. */
6354 /* Size of this segment in memory. */
6358 # if defined PT_GETDSBT
6359 struct target_loadmap
6361 /* Protocol version number, must be zero. */
6363 /* Pointer to the DSBT table, its size, and the DSBT index. */
6364 unsigned *dsbt_table
;
6365 unsigned dsbt_size
, dsbt_index
;
6366 /* Number of segments in this map. */
6368 /* The actual memory map. */
6369 struct target_loadseg segs
[/*nsegs*/];
6371 # define LINUX_LOADMAP PT_GETDSBT
6372 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6373 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6375 struct target_loadmap
6377 /* Protocol version number, must be zero. */
6379 /* Number of segments in this map. */
6381 /* The actual memory map. */
6382 struct target_loadseg segs
[/*nsegs*/];
6384 # define LINUX_LOADMAP PTRACE_GETFDPIC
6385 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6386 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6390 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
6391 unsigned char *myaddr
, unsigned int len
)
6393 int pid
= lwpid_of (current_thread
);
6395 struct target_loadmap
*data
= NULL
;
6396 unsigned int actual_length
, copy_length
;
6398 if (strcmp (annex
, "exec") == 0)
6399 addr
= (int) LINUX_LOADMAP_EXEC
;
6400 else if (strcmp (annex
, "interp") == 0)
6401 addr
= (int) LINUX_LOADMAP_INTERP
;
6405 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6411 actual_length
= sizeof (struct target_loadmap
)
6412 + sizeof (struct target_loadseg
) * data
->nsegs
;
6414 if (offset
< 0 || offset
> actual_length
)
6417 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6418 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6422 # define linux_read_loadmap NULL
6423 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6426 linux_process_qsupported (char **features
, int count
)
6428 if (the_low_target
.process_qsupported
!= NULL
)
6429 the_low_target
.process_qsupported (features
, count
);
6433 linux_supports_catch_syscall (void)
6435 return (the_low_target
.get_syscall_trapinfo
!= NULL
6436 && linux_supports_tracesysgood ());
6440 linux_get_ipa_tdesc_idx (void)
6442 if (the_low_target
.get_ipa_tdesc_idx
== NULL
)
6445 return (*the_low_target
.get_ipa_tdesc_idx
) ();
6449 linux_supports_tracepoints (void)
6451 if (*the_low_target
.supports_tracepoints
== NULL
)
6454 return (*the_low_target
.supports_tracepoints
) ();
6458 linux_read_pc (struct regcache
*regcache
)
6460 if (the_low_target
.get_pc
== NULL
)
6463 return (*the_low_target
.get_pc
) (regcache
);
6467 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
6469 gdb_assert (the_low_target
.set_pc
!= NULL
);
6471 (*the_low_target
.set_pc
) (regcache
, pc
);
6475 linux_thread_stopped (struct thread_info
*thread
)
6477 return get_thread_lwp (thread
)->stopped
;
6480 /* This exposes stop-all-threads functionality to other modules. */
6483 linux_pause_all (int freeze
)
6485 stop_all_lwps (freeze
, NULL
);
6488 /* This exposes unstop-all-threads functionality to other gdbserver
6492 linux_unpause_all (int unfreeze
)
6494 unstop_all_lwps (unfreeze
, NULL
);
6498 linux_prepare_to_access_memory (void)
6500 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6503 linux_pause_all (1);
6508 linux_done_accessing_memory (void)
6510 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6513 linux_unpause_all (1);
6517 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
6518 CORE_ADDR collector
,
6521 CORE_ADDR
*jump_entry
,
6522 CORE_ADDR
*trampoline
,
6523 ULONGEST
*trampoline_size
,
6524 unsigned char *jjump_pad_insn
,
6525 ULONGEST
*jjump_pad_insn_size
,
6526 CORE_ADDR
*adjusted_insn_addr
,
6527 CORE_ADDR
*adjusted_insn_addr_end
,
6530 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
6531 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
6532 jump_entry
, trampoline
, trampoline_size
,
6533 jjump_pad_insn
, jjump_pad_insn_size
,
6534 adjusted_insn_addr
, adjusted_insn_addr_end
,
6538 static struct emit_ops
*
6539 linux_emit_ops (void)
6541 if (the_low_target
.emit_ops
!= NULL
)
6542 return (*the_low_target
.emit_ops
) ();
6548 linux_get_min_fast_tracepoint_insn_len (void)
6550 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
6553 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6556 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6557 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6559 char filename
[PATH_MAX
];
6561 const int auxv_size
= is_elf64
6562 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6563 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6565 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6567 fd
= open (filename
, O_RDONLY
);
6573 while (read (fd
, buf
, auxv_size
) == auxv_size
6574 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6578 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6580 switch (aux
->a_type
)
6583 *phdr_memaddr
= aux
->a_un
.a_val
;
6586 *num_phdr
= aux
->a_un
.a_val
;
6592 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6594 switch (aux
->a_type
)
6597 *phdr_memaddr
= aux
->a_un
.a_val
;
6600 *num_phdr
= aux
->a_un
.a_val
;
6608 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6610 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6611 "phdr_memaddr = %ld, phdr_num = %d",
6612 (long) *phdr_memaddr
, *num_phdr
);
6619 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6622 get_dynamic (const int pid
, const int is_elf64
)
6624 CORE_ADDR phdr_memaddr
, relocation
;
6626 unsigned char *phdr_buf
;
6627 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6629 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6632 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6633 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6635 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6638 /* Compute relocation: it is expected to be 0 for "regular" executables,
6639 non-zero for PIE ones. */
6641 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6644 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6646 if (p
->p_type
== PT_PHDR
)
6647 relocation
= phdr_memaddr
- p
->p_vaddr
;
6651 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6653 if (p
->p_type
== PT_PHDR
)
6654 relocation
= phdr_memaddr
- p
->p_vaddr
;
6657 if (relocation
== -1)
6659 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6660 any real world executables, including PIE executables, have always
6661 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6662 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6663 or present DT_DEBUG anyway (fpc binaries are statically linked).
6665 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6667 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6672 for (i
= 0; i
< num_phdr
; i
++)
6676 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6678 if (p
->p_type
== PT_DYNAMIC
)
6679 return p
->p_vaddr
+ relocation
;
6683 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6685 if (p
->p_type
== PT_DYNAMIC
)
6686 return p
->p_vaddr
+ relocation
;
6693 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6694 can be 0 if the inferior does not yet have the library list initialized.
6695 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6696 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6699 get_r_debug (const int pid
, const int is_elf64
)
6701 CORE_ADDR dynamic_memaddr
;
6702 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6703 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6706 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6707 if (dynamic_memaddr
== 0)
6710 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6714 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6715 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6719 unsigned char buf
[sizeof (Elf64_Xword
)];
6723 #ifdef DT_MIPS_RLD_MAP
6724 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6726 if (linux_read_memory (dyn
->d_un
.d_val
,
6727 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6732 #endif /* DT_MIPS_RLD_MAP */
6733 #ifdef DT_MIPS_RLD_MAP_REL
6734 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6736 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6737 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6742 #endif /* DT_MIPS_RLD_MAP_REL */
6744 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6745 map
= dyn
->d_un
.d_val
;
6747 if (dyn
->d_tag
== DT_NULL
)
6752 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6753 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6757 unsigned char buf
[sizeof (Elf32_Word
)];
6761 #ifdef DT_MIPS_RLD_MAP
6762 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6764 if (linux_read_memory (dyn
->d_un
.d_val
,
6765 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6770 #endif /* DT_MIPS_RLD_MAP */
6771 #ifdef DT_MIPS_RLD_MAP_REL
6772 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6774 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6775 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6780 #endif /* DT_MIPS_RLD_MAP_REL */
6782 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6783 map
= dyn
->d_un
.d_val
;
6785 if (dyn
->d_tag
== DT_NULL
)
6789 dynamic_memaddr
+= dyn_size
;
6795 /* Read one pointer from MEMADDR in the inferior. */
6798 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6802 /* Go through a union so this works on either big or little endian
6803 hosts, when the inferior's pointer size is smaller than the size
6804 of CORE_ADDR. It is assumed the inferior's endianness is the
6805 same of the superior's. */
6808 CORE_ADDR core_addr
;
6813 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6816 if (ptr_size
== sizeof (CORE_ADDR
))
6817 *ptr
= addr
.core_addr
;
6818 else if (ptr_size
== sizeof (unsigned int))
6821 gdb_assert_not_reached ("unhandled pointer size");
6826 struct link_map_offsets
6828 /* Offset and size of r_debug.r_version. */
6829 int r_version_offset
;
6831 /* Offset and size of r_debug.r_map. */
6834 /* Offset to l_addr field in struct link_map. */
6837 /* Offset to l_name field in struct link_map. */
6840 /* Offset to l_ld field in struct link_map. */
6843 /* Offset to l_next field in struct link_map. */
6846 /* Offset to l_prev field in struct link_map. */
6850 /* Construct qXfer:libraries-svr4:read reply. */
6853 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6854 unsigned const char *writebuf
,
6855 CORE_ADDR offset
, int len
)
6858 unsigned document_len
;
6859 struct process_info_private
*const priv
= current_process ()->priv
;
6860 char filename
[PATH_MAX
];
6863 static const struct link_map_offsets lmo_32bit_offsets
=
6865 0, /* r_version offset. */
6866 4, /* r_debug.r_map offset. */
6867 0, /* l_addr offset in link_map. */
6868 4, /* l_name offset in link_map. */
6869 8, /* l_ld offset in link_map. */
6870 12, /* l_next offset in link_map. */
6871 16 /* l_prev offset in link_map. */
6874 static const struct link_map_offsets lmo_64bit_offsets
=
6876 0, /* r_version offset. */
6877 8, /* r_debug.r_map offset. */
6878 0, /* l_addr offset in link_map. */
6879 8, /* l_name offset in link_map. */
6880 16, /* l_ld offset in link_map. */
6881 24, /* l_next offset in link_map. */
6882 32 /* l_prev offset in link_map. */
6884 const struct link_map_offsets
*lmo
;
6885 unsigned int machine
;
6887 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6888 int allocated
= 1024;
6890 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6891 int header_done
= 0;
6893 if (writebuf
!= NULL
)
6895 if (readbuf
== NULL
)
6898 pid
= lwpid_of (current_thread
);
6899 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6900 is_elf64
= elf_64_file_p (filename
, &machine
);
6901 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6902 ptr_size
= is_elf64
? 8 : 4;
6904 while (annex
[0] != '\0')
6910 sep
= strchr (annex
, '=');
6915 if (len
== 5 && startswith (annex
, "start"))
6917 else if (len
== 4 && startswith (annex
, "prev"))
6921 annex
= strchr (sep
, ';');
6928 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6935 if (priv
->r_debug
== 0)
6936 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6938 /* We failed to find DT_DEBUG. Such situation will not change
6939 for this inferior - do not retry it. Report it to GDB as
6940 E01, see for the reasons at the GDB solib-svr4.c side. */
6941 if (priv
->r_debug
== (CORE_ADDR
) -1)
6944 if (priv
->r_debug
!= 0)
6946 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6947 (unsigned char *) &r_version
,
6948 sizeof (r_version
)) != 0
6951 warning ("unexpected r_debug version %d", r_version
);
6953 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6954 &lm_addr
, ptr_size
) != 0)
6956 warning ("unable to read r_map from 0x%lx",
6957 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6962 document
= (char *) xmalloc (allocated
);
6963 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
6964 p
= document
+ strlen (document
);
6967 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6968 &l_name
, ptr_size
) == 0
6969 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6970 &l_addr
, ptr_size
) == 0
6971 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6972 &l_ld
, ptr_size
) == 0
6973 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6974 &l_prev
, ptr_size
) == 0
6975 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6976 &l_next
, ptr_size
) == 0)
6978 unsigned char libname
[PATH_MAX
];
6980 if (lm_prev
!= l_prev
)
6982 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6983 (long) lm_prev
, (long) l_prev
);
6987 /* Ignore the first entry even if it has valid name as the first entry
6988 corresponds to the main executable. The first entry should not be
6989 skipped if the dynamic loader was loaded late by a static executable
6990 (see solib-svr4.c parameter ignore_first). But in such case the main
6991 executable does not have PT_DYNAMIC present and this function already
6992 exited above due to failed get_r_debug. */
6995 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
7000 /* Not checking for error because reading may stop before
7001 we've got PATH_MAX worth of characters. */
7003 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
7004 libname
[sizeof (libname
) - 1] = '\0';
7005 if (libname
[0] != '\0')
7007 /* 6x the size for xml_escape_text below. */
7008 size_t len
= 6 * strlen ((char *) libname
);
7013 /* Terminate `<library-list-svr4'. */
7018 while (allocated
< p
- document
+ len
+ 200)
7020 /* Expand to guarantee sufficient storage. */
7021 uintptr_t document_len
= p
- document
;
7023 document
= (char *) xrealloc (document
, 2 * allocated
);
7025 p
= document
+ document_len
;
7028 name
= xml_escape_text ((char *) libname
);
7029 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
7030 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
7031 name
, (unsigned long) lm_addr
,
7032 (unsigned long) l_addr
, (unsigned long) l_ld
);
7043 /* Empty list; terminate `<library-list-svr4'. */
7047 strcpy (p
, "</library-list-svr4>");
7049 document_len
= strlen (document
);
7050 if (offset
< document_len
)
7051 document_len
-= offset
;
7054 if (len
> document_len
)
7057 memcpy (readbuf
, document
+ offset
, len
);
7063 #ifdef HAVE_LINUX_BTRACE
7065 /* See to_disable_btrace target method. */
7068 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
7070 enum btrace_error err
;
7072 err
= linux_disable_btrace (tinfo
);
7073 return (err
== BTRACE_ERR_NONE
? 0 : -1);
7076 /* Encode an Intel Processor Trace configuration. */
7079 linux_low_encode_pt_config (struct buffer
*buffer
,
7080 const struct btrace_data_pt_config
*config
)
7082 buffer_grow_str (buffer
, "<pt-config>\n");
7084 switch (config
->cpu
.vendor
)
7087 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7088 "model=\"%u\" stepping=\"%u\"/>\n",
7089 config
->cpu
.family
, config
->cpu
.model
,
7090 config
->cpu
.stepping
);
7097 buffer_grow_str (buffer
, "</pt-config>\n");
7100 /* Encode a raw buffer. */
7103 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
7109 /* We use hex encoding - see common/rsp-low.h. */
7110 buffer_grow_str (buffer
, "<raw>\n");
7116 elem
[0] = tohex ((*data
>> 4) & 0xf);
7117 elem
[1] = tohex (*data
++ & 0xf);
7119 buffer_grow (buffer
, elem
, 2);
7122 buffer_grow_str (buffer
, "</raw>\n");
7125 /* See to_read_btrace target method. */
7128 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
7129 enum btrace_read_type type
)
7131 struct btrace_data btrace
;
7132 struct btrace_block
*block
;
7133 enum btrace_error err
;
7136 btrace_data_init (&btrace
);
7138 err
= linux_read_btrace (&btrace
, tinfo
, type
);
7139 if (err
!= BTRACE_ERR_NONE
)
7141 if (err
== BTRACE_ERR_OVERFLOW
)
7142 buffer_grow_str0 (buffer
, "E.Overflow.");
7144 buffer_grow_str0 (buffer
, "E.Generic Error.");
7149 switch (btrace
.format
)
7151 case BTRACE_FORMAT_NONE
:
7152 buffer_grow_str0 (buffer
, "E.No Trace.");
7155 case BTRACE_FORMAT_BTS
:
7156 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7157 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7160 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
7162 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7163 paddress (block
->begin
), paddress (block
->end
));
7165 buffer_grow_str0 (buffer
, "</btrace>\n");
7168 case BTRACE_FORMAT_PT
:
7169 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7170 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7171 buffer_grow_str (buffer
, "<pt>\n");
7173 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
7175 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
7176 btrace
.variant
.pt
.size
);
7178 buffer_grow_str (buffer
, "</pt>\n");
7179 buffer_grow_str0 (buffer
, "</btrace>\n");
7183 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
7187 btrace_data_fini (&btrace
);
7191 btrace_data_fini (&btrace
);
7195 /* See to_btrace_conf target method. */
7198 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
7199 struct buffer
*buffer
)
7201 const struct btrace_config
*conf
;
7203 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7204 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7206 conf
= linux_btrace_conf (tinfo
);
7209 switch (conf
->format
)
7211 case BTRACE_FORMAT_NONE
:
7214 case BTRACE_FORMAT_BTS
:
7215 buffer_xml_printf (buffer
, "<bts");
7216 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7217 buffer_xml_printf (buffer
, " />\n");
7220 case BTRACE_FORMAT_PT
:
7221 buffer_xml_printf (buffer
, "<pt");
7222 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7223 buffer_xml_printf (buffer
, "/>\n");
7228 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7231 #endif /* HAVE_LINUX_BTRACE */
7233 /* See nat/linux-nat.h. */
7236 current_lwp_ptid (void)
7238 return ptid_of (current_thread
);
7241 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7244 linux_breakpoint_kind_from_pc (CORE_ADDR
*pcptr
)
7246 if (the_low_target
.breakpoint_kind_from_pc
!= NULL
)
7247 return (*the_low_target
.breakpoint_kind_from_pc
) (pcptr
);
7249 return default_breakpoint_kind_from_pc (pcptr
);
7252 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7254 static const gdb_byte
*
7255 linux_sw_breakpoint_from_kind (int kind
, int *size
)
7257 gdb_assert (the_low_target
.sw_breakpoint_from_kind
!= NULL
);
7259 return (*the_low_target
.sw_breakpoint_from_kind
) (kind
, size
);
7262 /* Implementation of the target_ops method
7263 "breakpoint_kind_from_current_state". */
7266 linux_breakpoint_kind_from_current_state (CORE_ADDR
*pcptr
)
7268 if (the_low_target
.breakpoint_kind_from_current_state
!= NULL
)
7269 return (*the_low_target
.breakpoint_kind_from_current_state
) (pcptr
);
7271 return linux_breakpoint_kind_from_pc (pcptr
);
7274 /* Default implementation of linux_target_ops method "set_pc" for
7275 32-bit pc register which is literally named "pc". */
7278 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
7280 uint32_t newpc
= pc
;
7282 supply_register_by_name (regcache
, "pc", &newpc
);
7285 /* Default implementation of linux_target_ops method "get_pc" for
7286 32-bit pc register which is literally named "pc". */
7289 linux_get_pc_32bit (struct regcache
*regcache
)
7293 collect_register_by_name (regcache
, "pc", &pc
);
7295 debug_printf ("stop pc is 0x%" PRIx32
"\n", pc
);
7299 /* Default implementation of linux_target_ops method "set_pc" for
7300 64-bit pc register which is literally named "pc". */
7303 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
7305 uint64_t newpc
= pc
;
7307 supply_register_by_name (regcache
, "pc", &newpc
);
7310 /* Default implementation of linux_target_ops method "get_pc" for
7311 64-bit pc register which is literally named "pc". */
7314 linux_get_pc_64bit (struct regcache
*regcache
)
7318 collect_register_by_name (regcache
, "pc", &pc
);
7320 debug_printf ("stop pc is 0x%" PRIx64
"\n", pc
);
7325 static struct target_ops linux_target_ops
= {
7326 linux_create_inferior
,
7327 linux_post_create_inferior
,
7336 linux_fetch_registers
,
7337 linux_store_registers
,
7338 linux_prepare_to_access_memory
,
7339 linux_done_accessing_memory
,
7342 linux_look_up_symbols
,
7343 linux_request_interrupt
,
7345 linux_supports_z_point_type
,
7348 linux_stopped_by_sw_breakpoint
,
7349 linux_supports_stopped_by_sw_breakpoint
,
7350 linux_stopped_by_hw_breakpoint
,
7351 linux_supports_stopped_by_hw_breakpoint
,
7352 linux_supports_hardware_single_step
,
7353 linux_stopped_by_watchpoint
,
7354 linux_stopped_data_address
,
7355 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7356 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7357 && defined(PT_TEXT_END_ADDR)
7362 #ifdef USE_THREAD_DB
7363 thread_db_get_tls_address
,
7368 hostio_last_error_from_errno
,
7371 linux_supports_non_stop
,
7373 linux_start_non_stop
,
7374 linux_supports_multi_process
,
7375 linux_supports_fork_events
,
7376 linux_supports_vfork_events
,
7377 linux_supports_exec_events
,
7378 linux_handle_new_gdb_connection
,
7379 #ifdef USE_THREAD_DB
7380 thread_db_handle_monitor_command
,
7384 linux_common_core_of_thread
,
7386 linux_process_qsupported
,
7387 linux_supports_tracepoints
,
7390 linux_thread_stopped
,
7394 linux_stabilize_threads
,
7395 linux_install_fast_tracepoint_jump_pad
,
7397 linux_supports_disable_randomization
,
7398 linux_get_min_fast_tracepoint_insn_len
,
7399 linux_qxfer_libraries_svr4
,
7400 linux_supports_agent
,
7401 #ifdef HAVE_LINUX_BTRACE
7402 linux_supports_btrace
,
7403 linux_enable_btrace
,
7404 linux_low_disable_btrace
,
7405 linux_low_read_btrace
,
7406 linux_low_btrace_conf
,
7414 linux_supports_range_stepping
,
7415 linux_proc_pid_to_exec_file
,
7416 linux_mntns_open_cloexec
,
7418 linux_mntns_readlink
,
7419 linux_breakpoint_kind_from_pc
,
7420 linux_sw_breakpoint_from_kind
,
7421 linux_proc_tid_get_name
,
7422 linux_breakpoint_kind_from_current_state
,
7423 linux_supports_software_single_step
,
7424 linux_supports_catch_syscall
,
7425 linux_get_ipa_tdesc_idx
,
7428 #ifdef HAVE_LINUX_REGSETS
7430 initialize_regsets_info (struct regsets_info
*info
)
7432 for (info
->num_regsets
= 0;
7433 info
->regsets
[info
->num_regsets
].size
>= 0;
7434 info
->num_regsets
++)
7440 initialize_low (void)
7442 struct sigaction sigchld_action
;
7444 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7445 set_target_ops (&linux_target_ops
);
7447 linux_ptrace_init_warnings ();
7449 sigchld_action
.sa_handler
= sigchld_handler
;
7450 sigemptyset (&sigchld_action
.sa_mask
);
7451 sigchld_action
.sa_flags
= SA_RESTART
;
7452 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7454 initialize_low_arch ();
7456 linux_check_ptrace_features ();