1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2017 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 #include "event-loop.h"
65 #include "thread-fsm.h"
66 #include "common/enum-flags.h"
67 #include "progspace-and-thread.h"
68 #include "common/gdb_optional.h"
69 #include "arch-utils.h"
71 /* Prototypes for local functions */
73 static void info_signals_command (char *, int);
75 static void handle_command (char *, int);
77 static void sig_print_info (enum gdb_signal
);
79 static void sig_print_header (void);
81 static void resume_cleanups (void *);
83 static int hook_stop_stub (void *);
85 static int restore_selected_frame (void *);
87 static int follow_fork (void);
89 static int follow_fork_inferior (int follow_child
, int detach_fork
);
91 static void follow_inferior_reset_breakpoints (void);
93 static void set_schedlock_func (char *args
, int from_tty
,
94 struct cmd_list_element
*c
);
96 static int currently_stepping (struct thread_info
*tp
);
98 void _initialize_infrun (void);
100 void nullify_last_target_wait_ptid (void);
102 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
104 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
106 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
108 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
110 /* Asynchronous signal handler registered as event loop source for
111 when we have pending events ready to be passed to the core. */
112 static struct async_event_handler
*infrun_async_inferior_event_token
;
114 /* Stores whether infrun_async was previously enabled or disabled.
115 Starts off as -1, indicating "never enabled/disabled". */
116 static int infrun_is_async
= -1;
121 infrun_async (int enable
)
123 if (infrun_is_async
!= enable
)
125 infrun_is_async
= enable
;
128 fprintf_unfiltered (gdb_stdlog
,
129 "infrun: infrun_async(%d)\n",
133 mark_async_event_handler (infrun_async_inferior_event_token
);
135 clear_async_event_handler (infrun_async_inferior_event_token
);
142 mark_infrun_async_event_handler (void)
144 mark_async_event_handler (infrun_async_inferior_event_token
);
147 /* When set, stop the 'step' command if we enter a function which has
148 no line number information. The normal behavior is that we step
149 over such function. */
150 int step_stop_if_no_debug
= 0;
152 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
153 struct cmd_list_element
*c
, const char *value
)
155 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
158 /* proceed and normal_stop use this to notify the user when the
159 inferior stopped in a different thread than it had been running
162 static ptid_t previous_inferior_ptid
;
164 /* If set (default for legacy reasons), when following a fork, GDB
165 will detach from one of the fork branches, child or parent.
166 Exactly which branch is detached depends on 'set follow-fork-mode'
169 static int detach_fork
= 1;
171 int debug_displaced
= 0;
173 show_debug_displaced (struct ui_file
*file
, int from_tty
,
174 struct cmd_list_element
*c
, const char *value
)
176 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
179 unsigned int debug_infrun
= 0;
181 show_debug_infrun (struct ui_file
*file
, int from_tty
,
182 struct cmd_list_element
*c
, const char *value
)
184 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
188 /* Support for disabling address space randomization. */
190 int disable_randomization
= 1;
193 show_disable_randomization (struct ui_file
*file
, int from_tty
,
194 struct cmd_list_element
*c
, const char *value
)
196 if (target_supports_disable_randomization ())
197 fprintf_filtered (file
,
198 _("Disabling randomization of debuggee's "
199 "virtual address space is %s.\n"),
202 fputs_filtered (_("Disabling randomization of debuggee's "
203 "virtual address space is unsupported on\n"
204 "this platform.\n"), file
);
208 set_disable_randomization (char *args
, int from_tty
,
209 struct cmd_list_element
*c
)
211 if (!target_supports_disable_randomization ())
212 error (_("Disabling randomization of debuggee's "
213 "virtual address space is unsupported on\n"
217 /* User interface for non-stop mode. */
220 static int non_stop_1
= 0;
223 set_non_stop (char *args
, int from_tty
,
224 struct cmd_list_element
*c
)
226 if (target_has_execution
)
228 non_stop_1
= non_stop
;
229 error (_("Cannot change this setting while the inferior is running."));
232 non_stop
= non_stop_1
;
236 show_non_stop (struct ui_file
*file
, int from_tty
,
237 struct cmd_list_element
*c
, const char *value
)
239 fprintf_filtered (file
,
240 _("Controlling the inferior in non-stop mode is %s.\n"),
244 /* "Observer mode" is somewhat like a more extreme version of
245 non-stop, in which all GDB operations that might affect the
246 target's execution have been disabled. */
248 int observer_mode
= 0;
249 static int observer_mode_1
= 0;
252 set_observer_mode (char *args
, int from_tty
,
253 struct cmd_list_element
*c
)
255 if (target_has_execution
)
257 observer_mode_1
= observer_mode
;
258 error (_("Cannot change this setting while the inferior is running."));
261 observer_mode
= observer_mode_1
;
263 may_write_registers
= !observer_mode
;
264 may_write_memory
= !observer_mode
;
265 may_insert_breakpoints
= !observer_mode
;
266 may_insert_tracepoints
= !observer_mode
;
267 /* We can insert fast tracepoints in or out of observer mode,
268 but enable them if we're going into this mode. */
270 may_insert_fast_tracepoints
= 1;
271 may_stop
= !observer_mode
;
272 update_target_permissions ();
274 /* Going *into* observer mode we must force non-stop, then
275 going out we leave it that way. */
278 pagination_enabled
= 0;
279 non_stop
= non_stop_1
= 1;
283 printf_filtered (_("Observer mode is now %s.\n"),
284 (observer_mode
? "on" : "off"));
288 show_observer_mode (struct ui_file
*file
, int from_tty
,
289 struct cmd_list_element
*c
, const char *value
)
291 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
294 /* This updates the value of observer mode based on changes in
295 permissions. Note that we are deliberately ignoring the values of
296 may-write-registers and may-write-memory, since the user may have
297 reason to enable these during a session, for instance to turn on a
298 debugging-related global. */
301 update_observer_mode (void)
305 newval
= (!may_insert_breakpoints
306 && !may_insert_tracepoints
307 && may_insert_fast_tracepoints
311 /* Let the user know if things change. */
312 if (newval
!= observer_mode
)
313 printf_filtered (_("Observer mode is now %s.\n"),
314 (newval
? "on" : "off"));
316 observer_mode
= observer_mode_1
= newval
;
319 /* Tables of how to react to signals; the user sets them. */
321 static unsigned char *signal_stop
;
322 static unsigned char *signal_print
;
323 static unsigned char *signal_program
;
325 /* Table of signals that are registered with "catch signal". A
326 non-zero entry indicates that the signal is caught by some "catch
327 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
329 static unsigned char *signal_catch
;
331 /* Table of signals that the target may silently handle.
332 This is automatically determined from the flags above,
333 and simply cached here. */
334 static unsigned char *signal_pass
;
336 #define SET_SIGS(nsigs,sigs,flags) \
338 int signum = (nsigs); \
339 while (signum-- > 0) \
340 if ((sigs)[signum]) \
341 (flags)[signum] = 1; \
344 #define UNSET_SIGS(nsigs,sigs,flags) \
346 int signum = (nsigs); \
347 while (signum-- > 0) \
348 if ((sigs)[signum]) \
349 (flags)[signum] = 0; \
352 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
353 this function is to avoid exporting `signal_program'. */
356 update_signals_program_target (void)
358 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
361 /* Value to pass to target_resume() to cause all threads to resume. */
363 #define RESUME_ALL minus_one_ptid
365 /* Command list pointer for the "stop" placeholder. */
367 static struct cmd_list_element
*stop_command
;
369 /* Nonzero if we want to give control to the user when we're notified
370 of shared library events by the dynamic linker. */
371 int stop_on_solib_events
;
373 /* Enable or disable optional shared library event breakpoints
374 as appropriate when the above flag is changed. */
377 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
379 update_solib_breakpoints ();
383 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
384 struct cmd_list_element
*c
, const char *value
)
386 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
390 /* Nonzero after stop if current stack frame should be printed. */
392 static int stop_print_frame
;
394 /* This is a cached copy of the pid/waitstatus of the last event
395 returned by target_wait()/deprecated_target_wait_hook(). This
396 information is returned by get_last_target_status(). */
397 static ptid_t target_last_wait_ptid
;
398 static struct target_waitstatus target_last_waitstatus
;
400 static void context_switch (ptid_t ptid
);
402 void init_thread_stepping_state (struct thread_info
*tss
);
404 static const char follow_fork_mode_child
[] = "child";
405 static const char follow_fork_mode_parent
[] = "parent";
407 static const char *const follow_fork_mode_kind_names
[] = {
408 follow_fork_mode_child
,
409 follow_fork_mode_parent
,
413 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
415 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
416 struct cmd_list_element
*c
, const char *value
)
418 fprintf_filtered (file
,
419 _("Debugger response to a program "
420 "call of fork or vfork is \"%s\".\n"),
425 /* Handle changes to the inferior list based on the type of fork,
426 which process is being followed, and whether the other process
427 should be detached. On entry inferior_ptid must be the ptid of
428 the fork parent. At return inferior_ptid is the ptid of the
429 followed inferior. */
432 follow_fork_inferior (int follow_child
, int detach_fork
)
435 ptid_t parent_ptid
, child_ptid
;
437 has_vforked
= (inferior_thread ()->pending_follow
.kind
438 == TARGET_WAITKIND_VFORKED
);
439 parent_ptid
= inferior_ptid
;
440 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
443 && !non_stop
/* Non-stop always resumes both branches. */
444 && current_ui
->prompt_state
== PROMPT_BLOCKED
445 && !(follow_child
|| detach_fork
|| sched_multi
))
447 /* The parent stays blocked inside the vfork syscall until the
448 child execs or exits. If we don't let the child run, then
449 the parent stays blocked. If we're telling the parent to run
450 in the foreground, the user will not be able to ctrl-c to get
451 back the terminal, effectively hanging the debug session. */
452 fprintf_filtered (gdb_stderr
, _("\
453 Can not resume the parent process over vfork in the foreground while\n\
454 holding the child stopped. Try \"set detach-on-fork\" or \
455 \"set schedule-multiple\".\n"));
456 /* FIXME output string > 80 columns. */
462 /* Detach new forked process? */
465 /* Before detaching from the child, remove all breakpoints
466 from it. If we forked, then this has already been taken
467 care of by infrun.c. If we vforked however, any
468 breakpoint inserted in the parent is visible in the
469 child, even those added while stopped in a vfork
470 catchpoint. This will remove the breakpoints from the
471 parent also, but they'll be reinserted below. */
474 /* Keep breakpoints list in sync. */
475 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
478 if (info_verbose
|| debug_infrun
)
480 /* Ensure that we have a process ptid. */
481 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
483 target_terminal_ours_for_output ();
484 fprintf_filtered (gdb_stdlog
,
485 _("Detaching after %s from child %s.\n"),
486 has_vforked
? "vfork" : "fork",
487 target_pid_to_str (process_ptid
));
492 struct inferior
*parent_inf
, *child_inf
;
494 /* Add process to GDB's tables. */
495 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
497 parent_inf
= current_inferior ();
498 child_inf
->attach_flag
= parent_inf
->attach_flag
;
499 copy_terminal_info (child_inf
, parent_inf
);
500 child_inf
->gdbarch
= parent_inf
->gdbarch
;
501 copy_inferior_target_desc_info (child_inf
, parent_inf
);
503 scoped_restore_current_pspace_and_thread restore_pspace_thread
;
505 inferior_ptid
= child_ptid
;
506 add_thread (inferior_ptid
);
507 set_current_inferior (child_inf
);
508 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
510 /* If this is a vfork child, then the address-space is
511 shared with the parent. */
514 child_inf
->pspace
= parent_inf
->pspace
;
515 child_inf
->aspace
= parent_inf
->aspace
;
517 /* The parent will be frozen until the child is done
518 with the shared region. Keep track of the
520 child_inf
->vfork_parent
= parent_inf
;
521 child_inf
->pending_detach
= 0;
522 parent_inf
->vfork_child
= child_inf
;
523 parent_inf
->pending_detach
= 0;
527 child_inf
->aspace
= new_address_space ();
528 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
529 child_inf
->removable
= 1;
530 set_current_program_space (child_inf
->pspace
);
531 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
533 /* Let the shared library layer (e.g., solib-svr4) learn
534 about this new process, relocate the cloned exec, pull
535 in shared libraries, and install the solib event
536 breakpoint. If a "cloned-VM" event was propagated
537 better throughout the core, this wouldn't be
539 solib_create_inferior_hook (0);
545 struct inferior
*parent_inf
;
547 parent_inf
= current_inferior ();
549 /* If we detached from the child, then we have to be careful
550 to not insert breakpoints in the parent until the child
551 is done with the shared memory region. However, if we're
552 staying attached to the child, then we can and should
553 insert breakpoints, so that we can debug it. A
554 subsequent child exec or exit is enough to know when does
555 the child stops using the parent's address space. */
556 parent_inf
->waiting_for_vfork_done
= detach_fork
;
557 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
562 /* Follow the child. */
563 struct inferior
*parent_inf
, *child_inf
;
564 struct program_space
*parent_pspace
;
566 if (info_verbose
|| debug_infrun
)
568 target_terminal_ours_for_output ();
569 fprintf_filtered (gdb_stdlog
,
570 _("Attaching after %s %s to child %s.\n"),
571 target_pid_to_str (parent_ptid
),
572 has_vforked
? "vfork" : "fork",
573 target_pid_to_str (child_ptid
));
576 /* Add the new inferior first, so that the target_detach below
577 doesn't unpush the target. */
579 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
581 parent_inf
= current_inferior ();
582 child_inf
->attach_flag
= parent_inf
->attach_flag
;
583 copy_terminal_info (child_inf
, parent_inf
);
584 child_inf
->gdbarch
= parent_inf
->gdbarch
;
585 copy_inferior_target_desc_info (child_inf
, parent_inf
);
587 parent_pspace
= parent_inf
->pspace
;
589 /* If we're vforking, we want to hold on to the parent until the
590 child exits or execs. At child exec or exit time we can
591 remove the old breakpoints from the parent and detach or
592 resume debugging it. Otherwise, detach the parent now; we'll
593 want to reuse it's program/address spaces, but we can't set
594 them to the child before removing breakpoints from the
595 parent, otherwise, the breakpoints module could decide to
596 remove breakpoints from the wrong process (since they'd be
597 assigned to the same address space). */
601 gdb_assert (child_inf
->vfork_parent
== NULL
);
602 gdb_assert (parent_inf
->vfork_child
== NULL
);
603 child_inf
->vfork_parent
= parent_inf
;
604 child_inf
->pending_detach
= 0;
605 parent_inf
->vfork_child
= child_inf
;
606 parent_inf
->pending_detach
= detach_fork
;
607 parent_inf
->waiting_for_vfork_done
= 0;
609 else if (detach_fork
)
611 if (info_verbose
|| debug_infrun
)
613 /* Ensure that we have a process ptid. */
614 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
616 target_terminal_ours_for_output ();
617 fprintf_filtered (gdb_stdlog
,
618 _("Detaching after fork from "
620 target_pid_to_str (process_ptid
));
623 target_detach (NULL
, 0);
626 /* Note that the detach above makes PARENT_INF dangling. */
628 /* Add the child thread to the appropriate lists, and switch to
629 this new thread, before cloning the program space, and
630 informing the solib layer about this new process. */
632 inferior_ptid
= child_ptid
;
633 add_thread (inferior_ptid
);
634 set_current_inferior (child_inf
);
636 /* If this is a vfork child, then the address-space is shared
637 with the parent. If we detached from the parent, then we can
638 reuse the parent's program/address spaces. */
639 if (has_vforked
|| detach_fork
)
641 child_inf
->pspace
= parent_pspace
;
642 child_inf
->aspace
= child_inf
->pspace
->aspace
;
646 child_inf
->aspace
= new_address_space ();
647 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
648 child_inf
->removable
= 1;
649 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
650 set_current_program_space (child_inf
->pspace
);
651 clone_program_space (child_inf
->pspace
, parent_pspace
);
653 /* Let the shared library layer (e.g., solib-svr4) learn
654 about this new process, relocate the cloned exec, pull in
655 shared libraries, and install the solib event breakpoint.
656 If a "cloned-VM" event was propagated better throughout
657 the core, this wouldn't be required. */
658 solib_create_inferior_hook (0);
662 return target_follow_fork (follow_child
, detach_fork
);
665 /* Tell the target to follow the fork we're stopped at. Returns true
666 if the inferior should be resumed; false, if the target for some
667 reason decided it's best not to resume. */
672 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
673 int should_resume
= 1;
674 struct thread_info
*tp
;
676 /* Copy user stepping state to the new inferior thread. FIXME: the
677 followed fork child thread should have a copy of most of the
678 parent thread structure's run control related fields, not just these.
679 Initialized to avoid "may be used uninitialized" warnings from gcc. */
680 struct breakpoint
*step_resume_breakpoint
= NULL
;
681 struct breakpoint
*exception_resume_breakpoint
= NULL
;
682 CORE_ADDR step_range_start
= 0;
683 CORE_ADDR step_range_end
= 0;
684 struct frame_id step_frame_id
= { 0 };
685 struct thread_fsm
*thread_fsm
= NULL
;
690 struct target_waitstatus wait_status
;
692 /* Get the last target status returned by target_wait(). */
693 get_last_target_status (&wait_ptid
, &wait_status
);
695 /* If not stopped at a fork event, then there's nothing else to
697 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
698 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
701 /* Check if we switched over from WAIT_PTID, since the event was
703 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
704 && !ptid_equal (inferior_ptid
, wait_ptid
))
706 /* We did. Switch back to WAIT_PTID thread, to tell the
707 target to follow it (in either direction). We'll
708 afterwards refuse to resume, and inform the user what
710 switch_to_thread (wait_ptid
);
715 tp
= inferior_thread ();
717 /* If there were any forks/vforks that were caught and are now to be
718 followed, then do so now. */
719 switch (tp
->pending_follow
.kind
)
721 case TARGET_WAITKIND_FORKED
:
722 case TARGET_WAITKIND_VFORKED
:
724 ptid_t parent
, child
;
726 /* If the user did a next/step, etc, over a fork call,
727 preserve the stepping state in the fork child. */
728 if (follow_child
&& should_resume
)
730 step_resume_breakpoint
= clone_momentary_breakpoint
731 (tp
->control
.step_resume_breakpoint
);
732 step_range_start
= tp
->control
.step_range_start
;
733 step_range_end
= tp
->control
.step_range_end
;
734 step_frame_id
= tp
->control
.step_frame_id
;
735 exception_resume_breakpoint
736 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
737 thread_fsm
= tp
->thread_fsm
;
739 /* For now, delete the parent's sr breakpoint, otherwise,
740 parent/child sr breakpoints are considered duplicates,
741 and the child version will not be installed. Remove
742 this when the breakpoints module becomes aware of
743 inferiors and address spaces. */
744 delete_step_resume_breakpoint (tp
);
745 tp
->control
.step_range_start
= 0;
746 tp
->control
.step_range_end
= 0;
747 tp
->control
.step_frame_id
= null_frame_id
;
748 delete_exception_resume_breakpoint (tp
);
749 tp
->thread_fsm
= NULL
;
752 parent
= inferior_ptid
;
753 child
= tp
->pending_follow
.value
.related_pid
;
755 /* Set up inferior(s) as specified by the caller, and tell the
756 target to do whatever is necessary to follow either parent
758 if (follow_fork_inferior (follow_child
, detach_fork
))
760 /* Target refused to follow, or there's some other reason
761 we shouldn't resume. */
766 /* This pending follow fork event is now handled, one way
767 or another. The previous selected thread may be gone
768 from the lists by now, but if it is still around, need
769 to clear the pending follow request. */
770 tp
= find_thread_ptid (parent
);
772 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
774 /* This makes sure we don't try to apply the "Switched
775 over from WAIT_PID" logic above. */
776 nullify_last_target_wait_ptid ();
778 /* If we followed the child, switch to it... */
781 switch_to_thread (child
);
783 /* ... and preserve the stepping state, in case the
784 user was stepping over the fork call. */
787 tp
= inferior_thread ();
788 tp
->control
.step_resume_breakpoint
789 = step_resume_breakpoint
;
790 tp
->control
.step_range_start
= step_range_start
;
791 tp
->control
.step_range_end
= step_range_end
;
792 tp
->control
.step_frame_id
= step_frame_id
;
793 tp
->control
.exception_resume_breakpoint
794 = exception_resume_breakpoint
;
795 tp
->thread_fsm
= thread_fsm
;
799 /* If we get here, it was because we're trying to
800 resume from a fork catchpoint, but, the user
801 has switched threads away from the thread that
802 forked. In that case, the resume command
803 issued is most likely not applicable to the
804 child, so just warn, and refuse to resume. */
805 warning (_("Not resuming: switched threads "
806 "before following fork child."));
809 /* Reset breakpoints in the child as appropriate. */
810 follow_inferior_reset_breakpoints ();
813 switch_to_thread (parent
);
817 case TARGET_WAITKIND_SPURIOUS
:
818 /* Nothing to follow. */
821 internal_error (__FILE__
, __LINE__
,
822 "Unexpected pending_follow.kind %d\n",
823 tp
->pending_follow
.kind
);
827 return should_resume
;
831 follow_inferior_reset_breakpoints (void)
833 struct thread_info
*tp
= inferior_thread ();
835 /* Was there a step_resume breakpoint? (There was if the user
836 did a "next" at the fork() call.) If so, explicitly reset its
837 thread number. Cloned step_resume breakpoints are disabled on
838 creation, so enable it here now that it is associated with the
841 step_resumes are a form of bp that are made to be per-thread.
842 Since we created the step_resume bp when the parent process
843 was being debugged, and now are switching to the child process,
844 from the breakpoint package's viewpoint, that's a switch of
845 "threads". We must update the bp's notion of which thread
846 it is for, or it'll be ignored when it triggers. */
848 if (tp
->control
.step_resume_breakpoint
)
850 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
851 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
854 /* Treat exception_resume breakpoints like step_resume breakpoints. */
855 if (tp
->control
.exception_resume_breakpoint
)
857 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
858 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
861 /* Reinsert all breakpoints in the child. The user may have set
862 breakpoints after catching the fork, in which case those
863 were never set in the child, but only in the parent. This makes
864 sure the inserted breakpoints match the breakpoint list. */
866 breakpoint_re_set ();
867 insert_breakpoints ();
870 /* The child has exited or execed: resume threads of the parent the
871 user wanted to be executing. */
874 proceed_after_vfork_done (struct thread_info
*thread
,
877 int pid
= * (int *) arg
;
879 if (ptid_get_pid (thread
->ptid
) == pid
880 && is_running (thread
->ptid
)
881 && !is_executing (thread
->ptid
)
882 && !thread
->stop_requested
883 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
886 fprintf_unfiltered (gdb_stdlog
,
887 "infrun: resuming vfork parent thread %s\n",
888 target_pid_to_str (thread
->ptid
));
890 switch_to_thread (thread
->ptid
);
891 clear_proceed_status (0);
892 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
898 /* Save/restore inferior_ptid, current program space and current
899 inferior. Only use this if the current context points at an exited
900 inferior (and therefore there's no current thread to save). */
901 class scoped_restore_exited_inferior
904 scoped_restore_exited_inferior ()
905 : m_saved_ptid (&inferior_ptid
)
909 scoped_restore_tmpl
<ptid_t
> m_saved_ptid
;
910 scoped_restore_current_program_space m_pspace
;
911 scoped_restore_current_inferior m_inferior
;
914 /* Called whenever we notice an exec or exit event, to handle
915 detaching or resuming a vfork parent. */
918 handle_vfork_child_exec_or_exit (int exec
)
920 struct inferior
*inf
= current_inferior ();
922 if (inf
->vfork_parent
)
924 int resume_parent
= -1;
926 /* This exec or exit marks the end of the shared memory region
927 between the parent and the child. If the user wanted to
928 detach from the parent, now is the time. */
930 if (inf
->vfork_parent
->pending_detach
)
932 struct thread_info
*tp
;
933 struct program_space
*pspace
;
934 struct address_space
*aspace
;
936 /* follow-fork child, detach-on-fork on. */
938 inf
->vfork_parent
->pending_detach
= 0;
940 gdb::optional
<scoped_restore_exited_inferior
>
941 maybe_restore_inferior
;
942 gdb::optional
<scoped_restore_current_pspace_and_thread
>
943 maybe_restore_thread
;
945 /* If we're handling a child exit, then inferior_ptid points
946 at the inferior's pid, not to a thread. */
948 maybe_restore_inferior
.emplace ();
950 maybe_restore_thread
.emplace ();
952 /* We're letting loose of the parent. */
953 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
954 switch_to_thread (tp
->ptid
);
956 /* We're about to detach from the parent, which implicitly
957 removes breakpoints from its address space. There's a
958 catch here: we want to reuse the spaces for the child,
959 but, parent/child are still sharing the pspace at this
960 point, although the exec in reality makes the kernel give
961 the child a fresh set of new pages. The problem here is
962 that the breakpoints module being unaware of this, would
963 likely chose the child process to write to the parent
964 address space. Swapping the child temporarily away from
965 the spaces has the desired effect. Yes, this is "sort
968 pspace
= inf
->pspace
;
969 aspace
= inf
->aspace
;
973 if (debug_infrun
|| info_verbose
)
975 target_terminal_ours_for_output ();
979 fprintf_filtered (gdb_stdlog
,
980 _("Detaching vfork parent process "
981 "%d after child exec.\n"),
982 inf
->vfork_parent
->pid
);
986 fprintf_filtered (gdb_stdlog
,
987 _("Detaching vfork parent process "
988 "%d after child exit.\n"),
989 inf
->vfork_parent
->pid
);
993 target_detach (NULL
, 0);
996 inf
->pspace
= pspace
;
997 inf
->aspace
= aspace
;
1001 /* We're staying attached to the parent, so, really give the
1002 child a new address space. */
1003 inf
->pspace
= add_program_space (maybe_new_address_space ());
1004 inf
->aspace
= inf
->pspace
->aspace
;
1006 set_current_program_space (inf
->pspace
);
1008 resume_parent
= inf
->vfork_parent
->pid
;
1010 /* Break the bonds. */
1011 inf
->vfork_parent
->vfork_child
= NULL
;
1015 struct program_space
*pspace
;
1017 /* If this is a vfork child exiting, then the pspace and
1018 aspaces were shared with the parent. Since we're
1019 reporting the process exit, we'll be mourning all that is
1020 found in the address space, and switching to null_ptid,
1021 preparing to start a new inferior. But, since we don't
1022 want to clobber the parent's address/program spaces, we
1023 go ahead and create a new one for this exiting
1026 /* Switch to null_ptid while running clone_program_space, so
1027 that clone_program_space doesn't want to read the
1028 selected frame of a dead process. */
1029 scoped_restore restore_ptid
1030 = make_scoped_restore (&inferior_ptid
, null_ptid
);
1032 /* This inferior is dead, so avoid giving the breakpoints
1033 module the option to write through to it (cloning a
1034 program space resets breakpoints). */
1037 pspace
= add_program_space (maybe_new_address_space ());
1038 set_current_program_space (pspace
);
1040 inf
->symfile_flags
= SYMFILE_NO_READ
;
1041 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1042 inf
->pspace
= pspace
;
1043 inf
->aspace
= pspace
->aspace
;
1045 resume_parent
= inf
->vfork_parent
->pid
;
1046 /* Break the bonds. */
1047 inf
->vfork_parent
->vfork_child
= NULL
;
1050 inf
->vfork_parent
= NULL
;
1052 gdb_assert (current_program_space
== inf
->pspace
);
1054 if (non_stop
&& resume_parent
!= -1)
1056 /* If the user wanted the parent to be running, let it go
1058 scoped_restore_current_thread restore_thread
;
1061 fprintf_unfiltered (gdb_stdlog
,
1062 "infrun: resuming vfork parent process %d\n",
1065 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1070 /* Enum strings for "set|show follow-exec-mode". */
1072 static const char follow_exec_mode_new
[] = "new";
1073 static const char follow_exec_mode_same
[] = "same";
1074 static const char *const follow_exec_mode_names
[] =
1076 follow_exec_mode_new
,
1077 follow_exec_mode_same
,
1081 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1083 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1084 struct cmd_list_element
*c
, const char *value
)
1086 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1089 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1092 follow_exec (ptid_t ptid
, char *exec_file_target
)
1094 struct thread_info
*th
, *tmp
;
1095 struct inferior
*inf
= current_inferior ();
1096 int pid
= ptid_get_pid (ptid
);
1097 ptid_t process_ptid
;
1098 char *exec_file_host
;
1099 struct cleanup
*old_chain
;
1101 /* This is an exec event that we actually wish to pay attention to.
1102 Refresh our symbol table to the newly exec'd program, remove any
1103 momentary bp's, etc.
1105 If there are breakpoints, they aren't really inserted now,
1106 since the exec() transformed our inferior into a fresh set
1109 We want to preserve symbolic breakpoints on the list, since
1110 we have hopes that they can be reset after the new a.out's
1111 symbol table is read.
1113 However, any "raw" breakpoints must be removed from the list
1114 (e.g., the solib bp's), since their address is probably invalid
1117 And, we DON'T want to call delete_breakpoints() here, since
1118 that may write the bp's "shadow contents" (the instruction
1119 value that was overwritten witha TRAP instruction). Since
1120 we now have a new a.out, those shadow contents aren't valid. */
1122 mark_breakpoints_out ();
1124 /* The target reports the exec event to the main thread, even if
1125 some other thread does the exec, and even if the main thread was
1126 stopped or already gone. We may still have non-leader threads of
1127 the process on our list. E.g., on targets that don't have thread
1128 exit events (like remote); or on native Linux in non-stop mode if
1129 there were only two threads in the inferior and the non-leader
1130 one is the one that execs (and nothing forces an update of the
1131 thread list up to here). When debugging remotely, it's best to
1132 avoid extra traffic, when possible, so avoid syncing the thread
1133 list with the target, and instead go ahead and delete all threads
1134 of the process but one that reported the event. Note this must
1135 be done before calling update_breakpoints_after_exec, as
1136 otherwise clearing the threads' resources would reference stale
1137 thread breakpoints -- it may have been one of these threads that
1138 stepped across the exec. We could just clear their stepping
1139 states, but as long as we're iterating, might as well delete
1140 them. Deleting them now rather than at the next user-visible
1141 stop provides a nicer sequence of events for user and MI
1143 ALL_THREADS_SAFE (th
, tmp
)
1144 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1145 delete_thread (th
->ptid
);
1147 /* We also need to clear any left over stale state for the
1148 leader/event thread. E.g., if there was any step-resume
1149 breakpoint or similar, it's gone now. We cannot truly
1150 step-to-next statement through an exec(). */
1151 th
= inferior_thread ();
1152 th
->control
.step_resume_breakpoint
= NULL
;
1153 th
->control
.exception_resume_breakpoint
= NULL
;
1154 th
->control
.single_step_breakpoints
= NULL
;
1155 th
->control
.step_range_start
= 0;
1156 th
->control
.step_range_end
= 0;
1158 /* The user may have had the main thread held stopped in the
1159 previous image (e.g., schedlock on, or non-stop). Release
1161 th
->stop_requested
= 0;
1163 update_breakpoints_after_exec ();
1165 /* What is this a.out's name? */
1166 process_ptid
= pid_to_ptid (pid
);
1167 printf_unfiltered (_("%s is executing new program: %s\n"),
1168 target_pid_to_str (process_ptid
),
1171 /* We've followed the inferior through an exec. Therefore, the
1172 inferior has essentially been killed & reborn. */
1174 gdb_flush (gdb_stdout
);
1176 breakpoint_init_inferior (inf_execd
);
1178 exec_file_host
= exec_file_find (exec_file_target
, NULL
);
1179 old_chain
= make_cleanup (xfree
, exec_file_host
);
1181 /* If we were unable to map the executable target pathname onto a host
1182 pathname, tell the user that. Otherwise GDB's subsequent behavior
1183 is confusing. Maybe it would even be better to stop at this point
1184 so that the user can specify a file manually before continuing. */
1185 if (exec_file_host
== NULL
)
1186 warning (_("Could not load symbols for executable %s.\n"
1187 "Do you need \"set sysroot\"?"),
1190 /* Reset the shared library package. This ensures that we get a
1191 shlib event when the child reaches "_start", at which point the
1192 dld will have had a chance to initialize the child. */
1193 /* Also, loading a symbol file below may trigger symbol lookups, and
1194 we don't want those to be satisfied by the libraries of the
1195 previous incarnation of this process. */
1196 no_shared_libraries (NULL
, 0);
1198 if (follow_exec_mode_string
== follow_exec_mode_new
)
1200 /* The user wants to keep the old inferior and program spaces
1201 around. Create a new fresh one, and switch to it. */
1203 /* Do exit processing for the original inferior before adding
1204 the new inferior so we don't have two active inferiors with
1205 the same ptid, which can confuse find_inferior_ptid. */
1206 exit_inferior_num_silent (current_inferior ()->num
);
1208 inf
= add_inferior_with_spaces ();
1210 target_follow_exec (inf
, exec_file_target
);
1212 set_current_inferior (inf
);
1213 set_current_program_space (inf
->pspace
);
1218 /* The old description may no longer be fit for the new image.
1219 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1220 old description; we'll read a new one below. No need to do
1221 this on "follow-exec-mode new", as the old inferior stays
1222 around (its description is later cleared/refetched on
1224 target_clear_description ();
1227 gdb_assert (current_program_space
== inf
->pspace
);
1229 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1230 because the proper displacement for a PIE (Position Independent
1231 Executable) main symbol file will only be computed by
1232 solib_create_inferior_hook below. breakpoint_re_set would fail
1233 to insert the breakpoints with the zero displacement. */
1234 try_open_exec_file (exec_file_host
, inf
, SYMFILE_DEFER_BP_RESET
);
1236 do_cleanups (old_chain
);
1238 /* If the target can specify a description, read it. Must do this
1239 after flipping to the new executable (because the target supplied
1240 description must be compatible with the executable's
1241 architecture, and the old executable may e.g., be 32-bit, while
1242 the new one 64-bit), and before anything involving memory or
1244 target_find_description ();
1246 solib_create_inferior_hook (0);
1248 jit_inferior_created_hook ();
1250 breakpoint_re_set ();
1252 /* Reinsert all breakpoints. (Those which were symbolic have
1253 been reset to the proper address in the new a.out, thanks
1254 to symbol_file_command...). */
1255 insert_breakpoints ();
1257 /* The next resume of this inferior should bring it to the shlib
1258 startup breakpoints. (If the user had also set bp's on
1259 "main" from the old (parent) process, then they'll auto-
1260 matically get reset there in the new process.). */
1263 /* The queue of threads that need to do a step-over operation to get
1264 past e.g., a breakpoint. What technique is used to step over the
1265 breakpoint/watchpoint does not matter -- all threads end up in the
1266 same queue, to maintain rough temporal order of execution, in order
1267 to avoid starvation, otherwise, we could e.g., find ourselves
1268 constantly stepping the same couple threads past their breakpoints
1269 over and over, if the single-step finish fast enough. */
1270 struct thread_info
*step_over_queue_head
;
1272 /* Bit flags indicating what the thread needs to step over. */
1274 enum step_over_what_flag
1276 /* Step over a breakpoint. */
1277 STEP_OVER_BREAKPOINT
= 1,
1279 /* Step past a non-continuable watchpoint, in order to let the
1280 instruction execute so we can evaluate the watchpoint
1282 STEP_OVER_WATCHPOINT
= 2
1284 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1286 /* Info about an instruction that is being stepped over. */
1288 struct step_over_info
1290 /* If we're stepping past a breakpoint, this is the address space
1291 and address of the instruction the breakpoint is set at. We'll
1292 skip inserting all breakpoints here. Valid iff ASPACE is
1294 struct address_space
*aspace
;
1297 /* The instruction being stepped over triggers a nonsteppable
1298 watchpoint. If true, we'll skip inserting watchpoints. */
1299 int nonsteppable_watchpoint_p
;
1301 /* The thread's global number. */
1305 /* The step-over info of the location that is being stepped over.
1307 Note that with async/breakpoint always-inserted mode, a user might
1308 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1309 being stepped over. As setting a new breakpoint inserts all
1310 breakpoints, we need to make sure the breakpoint being stepped over
1311 isn't inserted then. We do that by only clearing the step-over
1312 info when the step-over is actually finished (or aborted).
1314 Presently GDB can only step over one breakpoint at any given time.
1315 Given threads that can't run code in the same address space as the
1316 breakpoint's can't really miss the breakpoint, GDB could be taught
1317 to step-over at most one breakpoint per address space (so this info
1318 could move to the address space object if/when GDB is extended).
1319 The set of breakpoints being stepped over will normally be much
1320 smaller than the set of all breakpoints, so a flag in the
1321 breakpoint location structure would be wasteful. A separate list
1322 also saves complexity and run-time, as otherwise we'd have to go
1323 through all breakpoint locations clearing their flag whenever we
1324 start a new sequence. Similar considerations weigh against storing
1325 this info in the thread object. Plus, not all step overs actually
1326 have breakpoint locations -- e.g., stepping past a single-step
1327 breakpoint, or stepping to complete a non-continuable
1329 static struct step_over_info step_over_info
;
1331 /* Record the address of the breakpoint/instruction we're currently
1333 N.B. We record the aspace and address now, instead of say just the thread,
1334 because when we need the info later the thread may be running. */
1337 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1338 int nonsteppable_watchpoint_p
,
1341 step_over_info
.aspace
= aspace
;
1342 step_over_info
.address
= address
;
1343 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1344 step_over_info
.thread
= thread
;
1347 /* Called when we're not longer stepping over a breakpoint / an
1348 instruction, so all breakpoints are free to be (re)inserted. */
1351 clear_step_over_info (void)
1354 fprintf_unfiltered (gdb_stdlog
,
1355 "infrun: clear_step_over_info\n");
1356 step_over_info
.aspace
= NULL
;
1357 step_over_info
.address
= 0;
1358 step_over_info
.nonsteppable_watchpoint_p
= 0;
1359 step_over_info
.thread
= -1;
1365 stepping_past_instruction_at (struct address_space
*aspace
,
1368 return (step_over_info
.aspace
!= NULL
1369 && breakpoint_address_match (aspace
, address
,
1370 step_over_info
.aspace
,
1371 step_over_info
.address
));
1377 thread_is_stepping_over_breakpoint (int thread
)
1379 return (step_over_info
.thread
!= -1
1380 && thread
== step_over_info
.thread
);
1386 stepping_past_nonsteppable_watchpoint (void)
1388 return step_over_info
.nonsteppable_watchpoint_p
;
1391 /* Returns true if step-over info is valid. */
1394 step_over_info_valid_p (void)
1396 return (step_over_info
.aspace
!= NULL
1397 || stepping_past_nonsteppable_watchpoint ());
1401 /* Displaced stepping. */
1403 /* In non-stop debugging mode, we must take special care to manage
1404 breakpoints properly; in particular, the traditional strategy for
1405 stepping a thread past a breakpoint it has hit is unsuitable.
1406 'Displaced stepping' is a tactic for stepping one thread past a
1407 breakpoint it has hit while ensuring that other threads running
1408 concurrently will hit the breakpoint as they should.
1410 The traditional way to step a thread T off a breakpoint in a
1411 multi-threaded program in all-stop mode is as follows:
1413 a0) Initially, all threads are stopped, and breakpoints are not
1415 a1) We single-step T, leaving breakpoints uninserted.
1416 a2) We insert breakpoints, and resume all threads.
1418 In non-stop debugging, however, this strategy is unsuitable: we
1419 don't want to have to stop all threads in the system in order to
1420 continue or step T past a breakpoint. Instead, we use displaced
1423 n0) Initially, T is stopped, other threads are running, and
1424 breakpoints are inserted.
1425 n1) We copy the instruction "under" the breakpoint to a separate
1426 location, outside the main code stream, making any adjustments
1427 to the instruction, register, and memory state as directed by
1429 n2) We single-step T over the instruction at its new location.
1430 n3) We adjust the resulting register and memory state as directed
1431 by T's architecture. This includes resetting T's PC to point
1432 back into the main instruction stream.
1435 This approach depends on the following gdbarch methods:
1437 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1438 indicate where to copy the instruction, and how much space must
1439 be reserved there. We use these in step n1.
1441 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1442 address, and makes any necessary adjustments to the instruction,
1443 register contents, and memory. We use this in step n1.
1445 - gdbarch_displaced_step_fixup adjusts registers and memory after
1446 we have successfuly single-stepped the instruction, to yield the
1447 same effect the instruction would have had if we had executed it
1448 at its original address. We use this in step n3.
1450 - gdbarch_displaced_step_free_closure provides cleanup.
1452 The gdbarch_displaced_step_copy_insn and
1453 gdbarch_displaced_step_fixup functions must be written so that
1454 copying an instruction with gdbarch_displaced_step_copy_insn,
1455 single-stepping across the copied instruction, and then applying
1456 gdbarch_displaced_insn_fixup should have the same effects on the
1457 thread's memory and registers as stepping the instruction in place
1458 would have. Exactly which responsibilities fall to the copy and
1459 which fall to the fixup is up to the author of those functions.
1461 See the comments in gdbarch.sh for details.
1463 Note that displaced stepping and software single-step cannot
1464 currently be used in combination, although with some care I think
1465 they could be made to. Software single-step works by placing
1466 breakpoints on all possible subsequent instructions; if the
1467 displaced instruction is a PC-relative jump, those breakpoints
1468 could fall in very strange places --- on pages that aren't
1469 executable, or at addresses that are not proper instruction
1470 boundaries. (We do generally let other threads run while we wait
1471 to hit the software single-step breakpoint, and they might
1472 encounter such a corrupted instruction.) One way to work around
1473 this would be to have gdbarch_displaced_step_copy_insn fully
1474 simulate the effect of PC-relative instructions (and return NULL)
1475 on architectures that use software single-stepping.
1477 In non-stop mode, we can have independent and simultaneous step
1478 requests, so more than one thread may need to simultaneously step
1479 over a breakpoint. The current implementation assumes there is
1480 only one scratch space per process. In this case, we have to
1481 serialize access to the scratch space. If thread A wants to step
1482 over a breakpoint, but we are currently waiting for some other
1483 thread to complete a displaced step, we leave thread A stopped and
1484 place it in the displaced_step_request_queue. Whenever a displaced
1485 step finishes, we pick the next thread in the queue and start a new
1486 displaced step operation on it. See displaced_step_prepare and
1487 displaced_step_fixup for details. */
1489 /* Per-inferior displaced stepping state. */
1490 struct displaced_step_inferior_state
1492 /* Pointer to next in linked list. */
1493 struct displaced_step_inferior_state
*next
;
1495 /* The process this displaced step state refers to. */
1498 /* True if preparing a displaced step ever failed. If so, we won't
1499 try displaced stepping for this inferior again. */
1502 /* If this is not null_ptid, this is the thread carrying out a
1503 displaced single-step in process PID. This thread's state will
1504 require fixing up once it has completed its step. */
1507 /* The architecture the thread had when we stepped it. */
1508 struct gdbarch
*step_gdbarch
;
1510 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1511 for post-step cleanup. */
1512 struct displaced_step_closure
*step_closure
;
1514 /* The address of the original instruction, and the copy we
1516 CORE_ADDR step_original
, step_copy
;
1518 /* Saved contents of copy area. */
1519 gdb_byte
*step_saved_copy
;
1522 /* The list of states of processes involved in displaced stepping
1524 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1526 /* Get the displaced stepping state of process PID. */
1528 static struct displaced_step_inferior_state
*
1529 get_displaced_stepping_state (int pid
)
1531 struct displaced_step_inferior_state
*state
;
1533 for (state
= displaced_step_inferior_states
;
1535 state
= state
->next
)
1536 if (state
->pid
== pid
)
1542 /* Returns true if any inferior has a thread doing a displaced
1546 displaced_step_in_progress_any_inferior (void)
1548 struct displaced_step_inferior_state
*state
;
1550 for (state
= displaced_step_inferior_states
;
1552 state
= state
->next
)
1553 if (!ptid_equal (state
->step_ptid
, null_ptid
))
1559 /* Return true if thread represented by PTID is doing a displaced
1563 displaced_step_in_progress_thread (ptid_t ptid
)
1565 struct displaced_step_inferior_state
*displaced
;
1567 gdb_assert (!ptid_equal (ptid
, null_ptid
));
1569 displaced
= get_displaced_stepping_state (ptid_get_pid (ptid
));
1571 return (displaced
!= NULL
&& ptid_equal (displaced
->step_ptid
, ptid
));
1574 /* Return true if process PID has a thread doing a displaced step. */
1577 displaced_step_in_progress (int pid
)
1579 struct displaced_step_inferior_state
*displaced
;
1581 displaced
= get_displaced_stepping_state (pid
);
1582 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1588 /* Add a new displaced stepping state for process PID to the displaced
1589 stepping state list, or return a pointer to an already existing
1590 entry, if it already exists. Never returns NULL. */
1592 static struct displaced_step_inferior_state
*
1593 add_displaced_stepping_state (int pid
)
1595 struct displaced_step_inferior_state
*state
;
1597 for (state
= displaced_step_inferior_states
;
1599 state
= state
->next
)
1600 if (state
->pid
== pid
)
1603 state
= XCNEW (struct displaced_step_inferior_state
);
1605 state
->next
= displaced_step_inferior_states
;
1606 displaced_step_inferior_states
= state
;
1611 /* If inferior is in displaced stepping, and ADDR equals to starting address
1612 of copy area, return corresponding displaced_step_closure. Otherwise,
1615 struct displaced_step_closure
*
1616 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1618 struct displaced_step_inferior_state
*displaced
1619 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1621 /* If checking the mode of displaced instruction in copy area. */
1622 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1623 && (displaced
->step_copy
== addr
))
1624 return displaced
->step_closure
;
1629 /* Remove the displaced stepping state of process PID. */
1632 remove_displaced_stepping_state (int pid
)
1634 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1636 gdb_assert (pid
!= 0);
1638 it
= displaced_step_inferior_states
;
1639 prev_next_p
= &displaced_step_inferior_states
;
1644 *prev_next_p
= it
->next
;
1649 prev_next_p
= &it
->next
;
1655 infrun_inferior_exit (struct inferior
*inf
)
1657 remove_displaced_stepping_state (inf
->pid
);
1660 /* If ON, and the architecture supports it, GDB will use displaced
1661 stepping to step over breakpoints. If OFF, or if the architecture
1662 doesn't support it, GDB will instead use the traditional
1663 hold-and-step approach. If AUTO (which is the default), GDB will
1664 decide which technique to use to step over breakpoints depending on
1665 which of all-stop or non-stop mode is active --- displaced stepping
1666 in non-stop mode; hold-and-step in all-stop mode. */
1668 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1671 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1672 struct cmd_list_element
*c
,
1675 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1676 fprintf_filtered (file
,
1677 _("Debugger's willingness to use displaced stepping "
1678 "to step over breakpoints is %s (currently %s).\n"),
1679 value
, target_is_non_stop_p () ? "on" : "off");
1681 fprintf_filtered (file
,
1682 _("Debugger's willingness to use displaced stepping "
1683 "to step over breakpoints is %s.\n"), value
);
1686 /* Return non-zero if displaced stepping can/should be used to step
1687 over breakpoints of thread TP. */
1690 use_displaced_stepping (struct thread_info
*tp
)
1692 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
1693 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1694 struct displaced_step_inferior_state
*displaced_state
;
1696 displaced_state
= get_displaced_stepping_state (ptid_get_pid (tp
->ptid
));
1698 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1699 && target_is_non_stop_p ())
1700 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1701 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1702 && find_record_target () == NULL
1703 && (displaced_state
== NULL
1704 || !displaced_state
->failed_before
));
1707 /* Clean out any stray displaced stepping state. */
1709 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1711 /* Indicate that there is no cleanup pending. */
1712 displaced
->step_ptid
= null_ptid
;
1714 xfree (displaced
->step_closure
);
1715 displaced
->step_closure
= NULL
;
1719 displaced_step_clear_cleanup (void *arg
)
1721 struct displaced_step_inferior_state
*state
1722 = (struct displaced_step_inferior_state
*) arg
;
1724 displaced_step_clear (state
);
1727 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1729 displaced_step_dump_bytes (struct ui_file
*file
,
1730 const gdb_byte
*buf
,
1735 for (i
= 0; i
< len
; i
++)
1736 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1737 fputs_unfiltered ("\n", file
);
1740 /* Prepare to single-step, using displaced stepping.
1742 Note that we cannot use displaced stepping when we have a signal to
1743 deliver. If we have a signal to deliver and an instruction to step
1744 over, then after the step, there will be no indication from the
1745 target whether the thread entered a signal handler or ignored the
1746 signal and stepped over the instruction successfully --- both cases
1747 result in a simple SIGTRAP. In the first case we mustn't do a
1748 fixup, and in the second case we must --- but we can't tell which.
1749 Comments in the code for 'random signals' in handle_inferior_event
1750 explain how we handle this case instead.
1752 Returns 1 if preparing was successful -- this thread is going to be
1753 stepped now; 0 if displaced stepping this thread got queued; or -1
1754 if this instruction can't be displaced stepped. */
1757 displaced_step_prepare_throw (ptid_t ptid
)
1759 struct cleanup
*ignore_cleanups
;
1760 struct thread_info
*tp
= find_thread_ptid (ptid
);
1761 struct regcache
*regcache
= get_thread_regcache (ptid
);
1762 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1763 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1764 CORE_ADDR original
, copy
;
1766 struct displaced_step_closure
*closure
;
1767 struct displaced_step_inferior_state
*displaced
;
1770 /* We should never reach this function if the architecture does not
1771 support displaced stepping. */
1772 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1774 /* Nor if the thread isn't meant to step over a breakpoint. */
1775 gdb_assert (tp
->control
.trap_expected
);
1777 /* Disable range stepping while executing in the scratch pad. We
1778 want a single-step even if executing the displaced instruction in
1779 the scratch buffer lands within the stepping range (e.g., a
1781 tp
->control
.may_range_step
= 0;
1783 /* We have to displaced step one thread at a time, as we only have
1784 access to a single scratch space per inferior. */
1786 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1788 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1790 /* Already waiting for a displaced step to finish. Defer this
1791 request and place in queue. */
1793 if (debug_displaced
)
1794 fprintf_unfiltered (gdb_stdlog
,
1795 "displaced: deferring step of %s\n",
1796 target_pid_to_str (ptid
));
1798 thread_step_over_chain_enqueue (tp
);
1803 if (debug_displaced
)
1804 fprintf_unfiltered (gdb_stdlog
,
1805 "displaced: stepping %s now\n",
1806 target_pid_to_str (ptid
));
1809 displaced_step_clear (displaced
);
1811 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
1812 inferior_ptid
= ptid
;
1814 original
= regcache_read_pc (regcache
);
1816 copy
= gdbarch_displaced_step_location (gdbarch
);
1817 len
= gdbarch_max_insn_length (gdbarch
);
1819 if (breakpoint_in_range_p (aspace
, copy
, len
))
1821 /* There's a breakpoint set in the scratch pad location range
1822 (which is usually around the entry point). We'd either
1823 install it before resuming, which would overwrite/corrupt the
1824 scratch pad, or if it was already inserted, this displaced
1825 step would overwrite it. The latter is OK in the sense that
1826 we already assume that no thread is going to execute the code
1827 in the scratch pad range (after initial startup) anyway, but
1828 the former is unacceptable. Simply punt and fallback to
1829 stepping over this breakpoint in-line. */
1830 if (debug_displaced
)
1832 fprintf_unfiltered (gdb_stdlog
,
1833 "displaced: breakpoint set in scratch pad. "
1834 "Stepping over breakpoint in-line instead.\n");
1840 /* Save the original contents of the copy area. */
1841 displaced
->step_saved_copy
= (gdb_byte
*) xmalloc (len
);
1842 ignore_cleanups
= make_cleanup (free_current_contents
,
1843 &displaced
->step_saved_copy
);
1844 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1846 throw_error (MEMORY_ERROR
,
1847 _("Error accessing memory address %s (%s) for "
1848 "displaced-stepping scratch space."),
1849 paddress (gdbarch
, copy
), safe_strerror (status
));
1850 if (debug_displaced
)
1852 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1853 paddress (gdbarch
, copy
));
1854 displaced_step_dump_bytes (gdb_stdlog
,
1855 displaced
->step_saved_copy
,
1859 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1860 original
, copy
, regcache
);
1861 if (closure
== NULL
)
1863 /* The architecture doesn't know how or want to displaced step
1864 this instruction or instruction sequence. Fallback to
1865 stepping over the breakpoint in-line. */
1866 do_cleanups (ignore_cleanups
);
1870 /* Save the information we need to fix things up if the step
1872 displaced
->step_ptid
= ptid
;
1873 displaced
->step_gdbarch
= gdbarch
;
1874 displaced
->step_closure
= closure
;
1875 displaced
->step_original
= original
;
1876 displaced
->step_copy
= copy
;
1878 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1880 /* Resume execution at the copy. */
1881 regcache_write_pc (regcache
, copy
);
1883 discard_cleanups (ignore_cleanups
);
1885 if (debug_displaced
)
1886 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1887 paddress (gdbarch
, copy
));
1892 /* Wrapper for displaced_step_prepare_throw that disabled further
1893 attempts at displaced stepping if we get a memory error. */
1896 displaced_step_prepare (ptid_t ptid
)
1902 prepared
= displaced_step_prepare_throw (ptid
);
1904 CATCH (ex
, RETURN_MASK_ERROR
)
1906 struct displaced_step_inferior_state
*displaced_state
;
1908 if (ex
.error
!= MEMORY_ERROR
1909 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1910 throw_exception (ex
);
1914 fprintf_unfiltered (gdb_stdlog
,
1915 "infrun: disabling displaced stepping: %s\n",
1919 /* Be verbose if "set displaced-stepping" is "on", silent if
1921 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1923 warning (_("disabling displaced stepping: %s"),
1927 /* Disable further displaced stepping attempts. */
1929 = get_displaced_stepping_state (ptid_get_pid (ptid
));
1930 displaced_state
->failed_before
= 1;
1938 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1939 const gdb_byte
*myaddr
, int len
)
1941 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
1943 inferior_ptid
= ptid
;
1944 write_memory (memaddr
, myaddr
, len
);
1947 /* Restore the contents of the copy area for thread PTID. */
1950 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1953 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1955 write_memory_ptid (ptid
, displaced
->step_copy
,
1956 displaced
->step_saved_copy
, len
);
1957 if (debug_displaced
)
1958 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1959 target_pid_to_str (ptid
),
1960 paddress (displaced
->step_gdbarch
,
1961 displaced
->step_copy
));
1964 /* If we displaced stepped an instruction successfully, adjust
1965 registers and memory to yield the same effect the instruction would
1966 have had if we had executed it at its original address, and return
1967 1. If the instruction didn't complete, relocate the PC and return
1968 -1. If the thread wasn't displaced stepping, return 0. */
1971 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1973 struct cleanup
*old_cleanups
;
1974 struct displaced_step_inferior_state
*displaced
1975 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1978 /* Was any thread of this process doing a displaced step? */
1979 if (displaced
== NULL
)
1982 /* Was this event for the pid we displaced? */
1983 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1984 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1987 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1989 displaced_step_restore (displaced
, displaced
->step_ptid
);
1991 /* Fixup may need to read memory/registers. Switch to the thread
1992 that we're fixing up. Also, target_stopped_by_watchpoint checks
1993 the current thread. */
1994 switch_to_thread (event_ptid
);
1996 /* Did the instruction complete successfully? */
1997 if (signal
== GDB_SIGNAL_TRAP
1998 && !(target_stopped_by_watchpoint ()
1999 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
2000 || target_have_steppable_watchpoint
)))
2002 /* Fix up the resulting state. */
2003 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
2004 displaced
->step_closure
,
2005 displaced
->step_original
,
2006 displaced
->step_copy
,
2007 get_thread_regcache (displaced
->step_ptid
));
2012 /* Since the instruction didn't complete, all we can do is
2014 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
2015 CORE_ADDR pc
= regcache_read_pc (regcache
);
2017 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
2018 regcache_write_pc (regcache
, pc
);
2022 do_cleanups (old_cleanups
);
2024 displaced
->step_ptid
= null_ptid
;
2029 /* Data to be passed around while handling an event. This data is
2030 discarded between events. */
2031 struct execution_control_state
2034 /* The thread that got the event, if this was a thread event; NULL
2036 struct thread_info
*event_thread
;
2038 struct target_waitstatus ws
;
2039 int stop_func_filled_in
;
2040 CORE_ADDR stop_func_start
;
2041 CORE_ADDR stop_func_end
;
2042 const char *stop_func_name
;
2045 /* True if the event thread hit the single-step breakpoint of
2046 another thread. Thus the event doesn't cause a stop, the thread
2047 needs to be single-stepped past the single-step breakpoint before
2048 we can switch back to the original stepping thread. */
2049 int hit_singlestep_breakpoint
;
2052 /* Clear ECS and set it to point at TP. */
2055 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
2057 memset (ecs
, 0, sizeof (*ecs
));
2058 ecs
->event_thread
= tp
;
2059 ecs
->ptid
= tp
->ptid
;
2062 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
2063 static void prepare_to_wait (struct execution_control_state
*ecs
);
2064 static int keep_going_stepped_thread (struct thread_info
*tp
);
2065 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
2067 /* Are there any pending step-over requests? If so, run all we can
2068 now and return true. Otherwise, return false. */
2071 start_step_over (void)
2073 struct thread_info
*tp
, *next
;
2075 /* Don't start a new step-over if we already have an in-line
2076 step-over operation ongoing. */
2077 if (step_over_info_valid_p ())
2080 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
2082 struct execution_control_state ecss
;
2083 struct execution_control_state
*ecs
= &ecss
;
2084 step_over_what step_what
;
2085 int must_be_in_line
;
2087 gdb_assert (!tp
->stop_requested
);
2089 next
= thread_step_over_chain_next (tp
);
2091 /* If this inferior already has a displaced step in process,
2092 don't start a new one. */
2093 if (displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2096 step_what
= thread_still_needs_step_over (tp
);
2097 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
2098 || ((step_what
& STEP_OVER_BREAKPOINT
)
2099 && !use_displaced_stepping (tp
)));
2101 /* We currently stop all threads of all processes to step-over
2102 in-line. If we need to start a new in-line step-over, let
2103 any pending displaced steps finish first. */
2104 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
2107 thread_step_over_chain_remove (tp
);
2109 if (step_over_queue_head
== NULL
)
2112 fprintf_unfiltered (gdb_stdlog
,
2113 "infrun: step-over queue now empty\n");
2116 if (tp
->control
.trap_expected
2120 internal_error (__FILE__
, __LINE__
,
2121 "[%s] has inconsistent state: "
2122 "trap_expected=%d, resumed=%d, executing=%d\n",
2123 target_pid_to_str (tp
->ptid
),
2124 tp
->control
.trap_expected
,
2130 fprintf_unfiltered (gdb_stdlog
,
2131 "infrun: resuming [%s] for step-over\n",
2132 target_pid_to_str (tp
->ptid
));
2134 /* keep_going_pass_signal skips the step-over if the breakpoint
2135 is no longer inserted. In all-stop, we want to keep looking
2136 for a thread that needs a step-over instead of resuming TP,
2137 because we wouldn't be able to resume anything else until the
2138 target stops again. In non-stop, the resume always resumes
2139 only TP, so it's OK to let the thread resume freely. */
2140 if (!target_is_non_stop_p () && !step_what
)
2143 switch_to_thread (tp
->ptid
);
2144 reset_ecs (ecs
, tp
);
2145 keep_going_pass_signal (ecs
);
2147 if (!ecs
->wait_some_more
)
2148 error (_("Command aborted."));
2150 gdb_assert (tp
->resumed
);
2152 /* If we started a new in-line step-over, we're done. */
2153 if (step_over_info_valid_p ())
2155 gdb_assert (tp
->control
.trap_expected
);
2159 if (!target_is_non_stop_p ())
2161 /* On all-stop, shouldn't have resumed unless we needed a
2163 gdb_assert (tp
->control
.trap_expected
2164 || tp
->step_after_step_resume_breakpoint
);
2166 /* With remote targets (at least), in all-stop, we can't
2167 issue any further remote commands until the program stops
2172 /* Either the thread no longer needed a step-over, or a new
2173 displaced stepping sequence started. Even in the latter
2174 case, continue looking. Maybe we can also start another
2175 displaced step on a thread of other process. */
2181 /* Update global variables holding ptids to hold NEW_PTID if they were
2182 holding OLD_PTID. */
2184 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2186 struct displaced_step_inferior_state
*displaced
;
2188 if (ptid_equal (inferior_ptid
, old_ptid
))
2189 inferior_ptid
= new_ptid
;
2191 for (displaced
= displaced_step_inferior_states
;
2193 displaced
= displaced
->next
)
2195 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
2196 displaced
->step_ptid
= new_ptid
;
2203 /* Things to clean up if we QUIT out of resume (). */
2205 resume_cleanups (void *ignore
)
2207 if (!ptid_equal (inferior_ptid
, null_ptid
))
2208 delete_single_step_breakpoints (inferior_thread ());
2213 static const char schedlock_off
[] = "off";
2214 static const char schedlock_on
[] = "on";
2215 static const char schedlock_step
[] = "step";
2216 static const char schedlock_replay
[] = "replay";
2217 static const char *const scheduler_enums
[] = {
2224 static const char *scheduler_mode
= schedlock_replay
;
2226 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2227 struct cmd_list_element
*c
, const char *value
)
2229 fprintf_filtered (file
,
2230 _("Mode for locking scheduler "
2231 "during execution is \"%s\".\n"),
2236 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
2238 if (!target_can_lock_scheduler
)
2240 scheduler_mode
= schedlock_off
;
2241 error (_("Target '%s' cannot support this command."), target_shortname
);
2245 /* True if execution commands resume all threads of all processes by
2246 default; otherwise, resume only threads of the current inferior
2248 int sched_multi
= 0;
2250 /* Try to setup for software single stepping over the specified location.
2251 Return 1 if target_resume() should use hardware single step.
2253 GDBARCH the current gdbarch.
2254 PC the location to step over. */
2257 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2261 if (execution_direction
== EXEC_FORWARD
2262 && gdbarch_software_single_step_p (gdbarch
))
2263 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2271 user_visible_resume_ptid (int step
)
2277 /* With non-stop mode on, threads are always handled
2279 resume_ptid
= inferior_ptid
;
2281 else if ((scheduler_mode
== schedlock_on
)
2282 || (scheduler_mode
== schedlock_step
&& step
))
2284 /* User-settable 'scheduler' mode requires solo thread
2286 resume_ptid
= inferior_ptid
;
2288 else if ((scheduler_mode
== schedlock_replay
)
2289 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2291 /* User-settable 'scheduler' mode requires solo thread resume in replay
2293 resume_ptid
= inferior_ptid
;
2295 else if (!sched_multi
&& target_supports_multi_process ())
2297 /* Resume all threads of the current process (and none of other
2299 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2303 /* Resume all threads of all processes. */
2304 resume_ptid
= RESUME_ALL
;
2310 /* Return a ptid representing the set of threads that we will resume,
2311 in the perspective of the target, assuming run control handling
2312 does not require leaving some threads stopped (e.g., stepping past
2313 breakpoint). USER_STEP indicates whether we're about to start the
2314 target for a stepping command. */
2317 internal_resume_ptid (int user_step
)
2319 /* In non-stop, we always control threads individually. Note that
2320 the target may always work in non-stop mode even with "set
2321 non-stop off", in which case user_visible_resume_ptid could
2322 return a wildcard ptid. */
2323 if (target_is_non_stop_p ())
2324 return inferior_ptid
;
2326 return user_visible_resume_ptid (user_step
);
2329 /* Wrapper for target_resume, that handles infrun-specific
2333 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2335 struct thread_info
*tp
= inferior_thread ();
2337 gdb_assert (!tp
->stop_requested
);
2339 /* Install inferior's terminal modes. */
2340 target_terminal_inferior ();
2342 /* Avoid confusing the next resume, if the next stop/resume
2343 happens to apply to another thread. */
2344 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2346 /* Advise target which signals may be handled silently.
2348 If we have removed breakpoints because we are stepping over one
2349 in-line (in any thread), we need to receive all signals to avoid
2350 accidentally skipping a breakpoint during execution of a signal
2353 Likewise if we're displaced stepping, otherwise a trap for a
2354 breakpoint in a signal handler might be confused with the
2355 displaced step finishing. We don't make the displaced_step_fixup
2356 step distinguish the cases instead, because:
2358 - a backtrace while stopped in the signal handler would show the
2359 scratch pad as frame older than the signal handler, instead of
2360 the real mainline code.
2362 - when the thread is later resumed, the signal handler would
2363 return to the scratch pad area, which would no longer be
2365 if (step_over_info_valid_p ()
2366 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2367 target_pass_signals (0, NULL
);
2369 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2371 target_resume (resume_ptid
, step
, sig
);
2373 target_commit_resume ();
2376 /* Resume the inferior, but allow a QUIT. This is useful if the user
2377 wants to interrupt some lengthy single-stepping operation
2378 (for child processes, the SIGINT goes to the inferior, and so
2379 we get a SIGINT random_signal, but for remote debugging and perhaps
2380 other targets, that's not true).
2382 SIG is the signal to give the inferior (zero for none). */
2384 resume (enum gdb_signal sig
)
2386 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2387 struct regcache
*regcache
= get_current_regcache ();
2388 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2389 struct thread_info
*tp
= inferior_thread ();
2390 CORE_ADDR pc
= regcache_read_pc (regcache
);
2391 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2393 /* This represents the user's step vs continue request. When
2394 deciding whether "set scheduler-locking step" applies, it's the
2395 user's intention that counts. */
2396 const int user_step
= tp
->control
.stepping_command
;
2397 /* This represents what we'll actually request the target to do.
2398 This can decay from a step to a continue, if e.g., we need to
2399 implement single-stepping with breakpoints (software
2403 gdb_assert (!tp
->stop_requested
);
2404 gdb_assert (!thread_is_in_step_over_chain (tp
));
2408 if (tp
->suspend
.waitstatus_pending_p
)
2414 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2415 fprintf_unfiltered (gdb_stdlog
,
2416 "infrun: resume: thread %s has pending wait status %s "
2417 "(currently_stepping=%d).\n",
2418 target_pid_to_str (tp
->ptid
), statstr
,
2419 currently_stepping (tp
));
2425 /* FIXME: What should we do if we are supposed to resume this
2426 thread with a signal? Maybe we should maintain a queue of
2427 pending signals to deliver. */
2428 if (sig
!= GDB_SIGNAL_0
)
2430 warning (_("Couldn't deliver signal %s to %s."),
2431 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2434 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2435 discard_cleanups (old_cleanups
);
2437 if (target_can_async_p ())
2442 tp
->stepped_breakpoint
= 0;
2444 /* Depends on stepped_breakpoint. */
2445 step
= currently_stepping (tp
);
2447 if (current_inferior ()->waiting_for_vfork_done
)
2449 /* Don't try to single-step a vfork parent that is waiting for
2450 the child to get out of the shared memory region (by exec'ing
2451 or exiting). This is particularly important on software
2452 single-step archs, as the child process would trip on the
2453 software single step breakpoint inserted for the parent
2454 process. Since the parent will not actually execute any
2455 instruction until the child is out of the shared region (such
2456 are vfork's semantics), it is safe to simply continue it.
2457 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2458 the parent, and tell it to `keep_going', which automatically
2459 re-sets it stepping. */
2461 fprintf_unfiltered (gdb_stdlog
,
2462 "infrun: resume : clear step\n");
2467 fprintf_unfiltered (gdb_stdlog
,
2468 "infrun: resume (step=%d, signal=%s), "
2469 "trap_expected=%d, current thread [%s] at %s\n",
2470 step
, gdb_signal_to_symbol_string (sig
),
2471 tp
->control
.trap_expected
,
2472 target_pid_to_str (inferior_ptid
),
2473 paddress (gdbarch
, pc
));
2475 /* Normally, by the time we reach `resume', the breakpoints are either
2476 removed or inserted, as appropriate. The exception is if we're sitting
2477 at a permanent breakpoint; we need to step over it, but permanent
2478 breakpoints can't be removed. So we have to test for it here. */
2479 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2481 if (sig
!= GDB_SIGNAL_0
)
2483 /* We have a signal to pass to the inferior. The resume
2484 may, or may not take us to the signal handler. If this
2485 is a step, we'll need to stop in the signal handler, if
2486 there's one, (if the target supports stepping into
2487 handlers), or in the next mainline instruction, if
2488 there's no handler. If this is a continue, we need to be
2489 sure to run the handler with all breakpoints inserted.
2490 In all cases, set a breakpoint at the current address
2491 (where the handler returns to), and once that breakpoint
2492 is hit, resume skipping the permanent breakpoint. If
2493 that breakpoint isn't hit, then we've stepped into the
2494 signal handler (or hit some other event). We'll delete
2495 the step-resume breakpoint then. */
2498 fprintf_unfiltered (gdb_stdlog
,
2499 "infrun: resume: skipping permanent breakpoint, "
2500 "deliver signal first\n");
2502 clear_step_over_info ();
2503 tp
->control
.trap_expected
= 0;
2505 if (tp
->control
.step_resume_breakpoint
== NULL
)
2507 /* Set a "high-priority" step-resume, as we don't want
2508 user breakpoints at PC to trigger (again) when this
2510 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2511 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2513 tp
->step_after_step_resume_breakpoint
= step
;
2516 insert_breakpoints ();
2520 /* There's no signal to pass, we can go ahead and skip the
2521 permanent breakpoint manually. */
2523 fprintf_unfiltered (gdb_stdlog
,
2524 "infrun: resume: skipping permanent breakpoint\n");
2525 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2526 /* Update pc to reflect the new address from which we will
2527 execute instructions. */
2528 pc
= regcache_read_pc (regcache
);
2532 /* We've already advanced the PC, so the stepping part
2533 is done. Now we need to arrange for a trap to be
2534 reported to handle_inferior_event. Set a breakpoint
2535 at the current PC, and run to it. Don't update
2536 prev_pc, because if we end in
2537 switch_back_to_stepped_thread, we want the "expected
2538 thread advanced also" branch to be taken. IOW, we
2539 don't want this thread to step further from PC
2541 gdb_assert (!step_over_info_valid_p ());
2542 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2543 insert_breakpoints ();
2545 resume_ptid
= internal_resume_ptid (user_step
);
2546 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2547 discard_cleanups (old_cleanups
);
2554 /* If we have a breakpoint to step over, make sure to do a single
2555 step only. Same if we have software watchpoints. */
2556 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2557 tp
->control
.may_range_step
= 0;
2559 /* If enabled, step over breakpoints by executing a copy of the
2560 instruction at a different address.
2562 We can't use displaced stepping when we have a signal to deliver;
2563 the comments for displaced_step_prepare explain why. The
2564 comments in the handle_inferior event for dealing with 'random
2565 signals' explain what we do instead.
2567 We can't use displaced stepping when we are waiting for vfork_done
2568 event, displaced stepping breaks the vfork child similarly as single
2569 step software breakpoint. */
2570 if (tp
->control
.trap_expected
2571 && use_displaced_stepping (tp
)
2572 && !step_over_info_valid_p ()
2573 && sig
== GDB_SIGNAL_0
2574 && !current_inferior ()->waiting_for_vfork_done
)
2576 int prepared
= displaced_step_prepare (inferior_ptid
);
2581 fprintf_unfiltered (gdb_stdlog
,
2582 "Got placed in step-over queue\n");
2584 tp
->control
.trap_expected
= 0;
2585 discard_cleanups (old_cleanups
);
2588 else if (prepared
< 0)
2590 /* Fallback to stepping over the breakpoint in-line. */
2592 if (target_is_non_stop_p ())
2593 stop_all_threads ();
2595 set_step_over_info (get_regcache_aspace (regcache
),
2596 regcache_read_pc (regcache
), 0, tp
->global_num
);
2598 step
= maybe_software_singlestep (gdbarch
, pc
);
2600 insert_breakpoints ();
2602 else if (prepared
> 0)
2604 struct displaced_step_inferior_state
*displaced
;
2606 /* Update pc to reflect the new address from which we will
2607 execute instructions due to displaced stepping. */
2608 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2610 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2611 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2612 displaced
->step_closure
);
2616 /* Do we need to do it the hard way, w/temp breakpoints? */
2618 step
= maybe_software_singlestep (gdbarch
, pc
);
2620 /* Currently, our software single-step implementation leads to different
2621 results than hardware single-stepping in one situation: when stepping
2622 into delivering a signal which has an associated signal handler,
2623 hardware single-step will stop at the first instruction of the handler,
2624 while software single-step will simply skip execution of the handler.
2626 For now, this difference in behavior is accepted since there is no
2627 easy way to actually implement single-stepping into a signal handler
2628 without kernel support.
2630 However, there is one scenario where this difference leads to follow-on
2631 problems: if we're stepping off a breakpoint by removing all breakpoints
2632 and then single-stepping. In this case, the software single-step
2633 behavior means that even if there is a *breakpoint* in the signal
2634 handler, GDB still would not stop.
2636 Fortunately, we can at least fix this particular issue. We detect
2637 here the case where we are about to deliver a signal while software
2638 single-stepping with breakpoints removed. In this situation, we
2639 revert the decisions to remove all breakpoints and insert single-
2640 step breakpoints, and instead we install a step-resume breakpoint
2641 at the current address, deliver the signal without stepping, and
2642 once we arrive back at the step-resume breakpoint, actually step
2643 over the breakpoint we originally wanted to step over. */
2644 if (thread_has_single_step_breakpoints_set (tp
)
2645 && sig
!= GDB_SIGNAL_0
2646 && step_over_info_valid_p ())
2648 /* If we have nested signals or a pending signal is delivered
2649 immediately after a handler returns, might might already have
2650 a step-resume breakpoint set on the earlier handler. We cannot
2651 set another step-resume breakpoint; just continue on until the
2652 original breakpoint is hit. */
2653 if (tp
->control
.step_resume_breakpoint
== NULL
)
2655 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2656 tp
->step_after_step_resume_breakpoint
= 1;
2659 delete_single_step_breakpoints (tp
);
2661 clear_step_over_info ();
2662 tp
->control
.trap_expected
= 0;
2664 insert_breakpoints ();
2667 /* If STEP is set, it's a request to use hardware stepping
2668 facilities. But in that case, we should never
2669 use singlestep breakpoint. */
2670 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2672 /* Decide the set of threads to ask the target to resume. */
2673 if (tp
->control
.trap_expected
)
2675 /* We're allowing a thread to run past a breakpoint it has
2676 hit, either by single-stepping the thread with the breakpoint
2677 removed, or by displaced stepping, with the breakpoint inserted.
2678 In the former case, we need to single-step only this thread,
2679 and keep others stopped, as they can miss this breakpoint if
2680 allowed to run. That's not really a problem for displaced
2681 stepping, but, we still keep other threads stopped, in case
2682 another thread is also stopped for a breakpoint waiting for
2683 its turn in the displaced stepping queue. */
2684 resume_ptid
= inferior_ptid
;
2687 resume_ptid
= internal_resume_ptid (user_step
);
2689 if (execution_direction
!= EXEC_REVERSE
2690 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2692 /* There are two cases where we currently need to step a
2693 breakpoint instruction when we have a signal to deliver:
2695 - See handle_signal_stop where we handle random signals that
2696 could take out us out of the stepping range. Normally, in
2697 that case we end up continuing (instead of stepping) over the
2698 signal handler with a breakpoint at PC, but there are cases
2699 where we should _always_ single-step, even if we have a
2700 step-resume breakpoint, like when a software watchpoint is
2701 set. Assuming single-stepping and delivering a signal at the
2702 same time would takes us to the signal handler, then we could
2703 have removed the breakpoint at PC to step over it. However,
2704 some hardware step targets (like e.g., Mac OS) can't step
2705 into signal handlers, and for those, we need to leave the
2706 breakpoint at PC inserted, as otherwise if the handler
2707 recurses and executes PC again, it'll miss the breakpoint.
2708 So we leave the breakpoint inserted anyway, but we need to
2709 record that we tried to step a breakpoint instruction, so
2710 that adjust_pc_after_break doesn't end up confused.
2712 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2713 in one thread after another thread that was stepping had been
2714 momentarily paused for a step-over. When we re-resume the
2715 stepping thread, it may be resumed from that address with a
2716 breakpoint that hasn't trapped yet. Seen with
2717 gdb.threads/non-stop-fair-events.exp, on targets that don't
2718 do displaced stepping. */
2721 fprintf_unfiltered (gdb_stdlog
,
2722 "infrun: resume: [%s] stepped breakpoint\n",
2723 target_pid_to_str (tp
->ptid
));
2725 tp
->stepped_breakpoint
= 1;
2727 /* Most targets can step a breakpoint instruction, thus
2728 executing it normally. But if this one cannot, just
2729 continue and we will hit it anyway. */
2730 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2735 && tp
->control
.trap_expected
2736 && use_displaced_stepping (tp
)
2737 && !step_over_info_valid_p ())
2739 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2740 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2741 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2744 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2745 paddress (resume_gdbarch
, actual_pc
));
2746 read_memory (actual_pc
, buf
, sizeof (buf
));
2747 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2750 if (tp
->control
.may_range_step
)
2752 /* If we're resuming a thread with the PC out of the step
2753 range, then we're doing some nested/finer run control
2754 operation, like stepping the thread out of the dynamic
2755 linker or the displaced stepping scratch pad. We
2756 shouldn't have allowed a range step then. */
2757 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2760 do_target_resume (resume_ptid
, step
, sig
);
2762 discard_cleanups (old_cleanups
);
2769 /* Counter that tracks number of user visible stops. This can be used
2770 to tell whether a command has proceeded the inferior past the
2771 current location. This allows e.g., inferior function calls in
2772 breakpoint commands to not interrupt the command list. When the
2773 call finishes successfully, the inferior is standing at the same
2774 breakpoint as if nothing happened (and so we don't call
2776 static ULONGEST current_stop_id
;
2783 return current_stop_id
;
2786 /* Called when we report a user visible stop. */
2794 /* Clear out all variables saying what to do when inferior is continued.
2795 First do this, then set the ones you want, then call `proceed'. */
2798 clear_proceed_status_thread (struct thread_info
*tp
)
2801 fprintf_unfiltered (gdb_stdlog
,
2802 "infrun: clear_proceed_status_thread (%s)\n",
2803 target_pid_to_str (tp
->ptid
));
2805 /* If we're starting a new sequence, then the previous finished
2806 single-step is no longer relevant. */
2807 if (tp
->suspend
.waitstatus_pending_p
)
2809 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2812 fprintf_unfiltered (gdb_stdlog
,
2813 "infrun: clear_proceed_status: pending "
2814 "event of %s was a finished step. "
2816 target_pid_to_str (tp
->ptid
));
2818 tp
->suspend
.waitstatus_pending_p
= 0;
2819 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2821 else if (debug_infrun
)
2825 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2826 fprintf_unfiltered (gdb_stdlog
,
2827 "infrun: clear_proceed_status_thread: thread %s "
2828 "has pending wait status %s "
2829 "(currently_stepping=%d).\n",
2830 target_pid_to_str (tp
->ptid
), statstr
,
2831 currently_stepping (tp
));
2836 /* If this signal should not be seen by program, give it zero.
2837 Used for debugging signals. */
2838 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2839 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2841 thread_fsm_delete (tp
->thread_fsm
);
2842 tp
->thread_fsm
= NULL
;
2844 tp
->control
.trap_expected
= 0;
2845 tp
->control
.step_range_start
= 0;
2846 tp
->control
.step_range_end
= 0;
2847 tp
->control
.may_range_step
= 0;
2848 tp
->control
.step_frame_id
= null_frame_id
;
2849 tp
->control
.step_stack_frame_id
= null_frame_id
;
2850 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2851 tp
->control
.step_start_function
= NULL
;
2852 tp
->stop_requested
= 0;
2854 tp
->control
.stop_step
= 0;
2856 tp
->control
.proceed_to_finish
= 0;
2858 tp
->control
.stepping_command
= 0;
2860 /* Discard any remaining commands or status from previous stop. */
2861 bpstat_clear (&tp
->control
.stop_bpstat
);
2865 clear_proceed_status (int step
)
2867 /* With scheduler-locking replay, stop replaying other threads if we're
2868 not replaying the user-visible resume ptid.
2870 This is a convenience feature to not require the user to explicitly
2871 stop replaying the other threads. We're assuming that the user's
2872 intent is to resume tracing the recorded process. */
2873 if (!non_stop
&& scheduler_mode
== schedlock_replay
2874 && target_record_is_replaying (minus_one_ptid
)
2875 && !target_record_will_replay (user_visible_resume_ptid (step
),
2876 execution_direction
))
2877 target_record_stop_replaying ();
2881 struct thread_info
*tp
;
2884 resume_ptid
= user_visible_resume_ptid (step
);
2886 /* In all-stop mode, delete the per-thread status of all threads
2887 we're about to resume, implicitly and explicitly. */
2888 ALL_NON_EXITED_THREADS (tp
)
2890 if (!ptid_match (tp
->ptid
, resume_ptid
))
2892 clear_proceed_status_thread (tp
);
2896 if (!ptid_equal (inferior_ptid
, null_ptid
))
2898 struct inferior
*inferior
;
2902 /* If in non-stop mode, only delete the per-thread status of
2903 the current thread. */
2904 clear_proceed_status_thread (inferior_thread ());
2907 inferior
= current_inferior ();
2908 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2911 observer_notify_about_to_proceed ();
2914 /* Returns true if TP is still stopped at a breakpoint that needs
2915 stepping-over in order to make progress. If the breakpoint is gone
2916 meanwhile, we can skip the whole step-over dance. */
2919 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2921 if (tp
->stepping_over_breakpoint
)
2923 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2925 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2926 regcache_read_pc (regcache
))
2927 == ordinary_breakpoint_here
)
2930 tp
->stepping_over_breakpoint
= 0;
2936 /* Check whether thread TP still needs to start a step-over in order
2937 to make progress when resumed. Returns an bitwise or of enum
2938 step_over_what bits, indicating what needs to be stepped over. */
2940 static step_over_what
2941 thread_still_needs_step_over (struct thread_info
*tp
)
2943 step_over_what what
= 0;
2945 if (thread_still_needs_step_over_bp (tp
))
2946 what
|= STEP_OVER_BREAKPOINT
;
2948 if (tp
->stepping_over_watchpoint
2949 && !target_have_steppable_watchpoint
)
2950 what
|= STEP_OVER_WATCHPOINT
;
2955 /* Returns true if scheduler locking applies. STEP indicates whether
2956 we're about to do a step/next-like command to a thread. */
2959 schedlock_applies (struct thread_info
*tp
)
2961 return (scheduler_mode
== schedlock_on
2962 || (scheduler_mode
== schedlock_step
2963 && tp
->control
.stepping_command
)
2964 || (scheduler_mode
== schedlock_replay
2965 && target_record_will_replay (minus_one_ptid
,
2966 execution_direction
)));
2969 /* Basic routine for continuing the program in various fashions.
2971 ADDR is the address to resume at, or -1 for resume where stopped.
2972 SIGGNAL is the signal to give it, or 0 for none,
2973 or -1 for act according to how it stopped.
2974 STEP is nonzero if should trap after one instruction.
2975 -1 means return after that and print nothing.
2976 You should probably set various step_... variables
2977 before calling here, if you are stepping.
2979 You should call clear_proceed_status before calling proceed. */
2982 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2984 struct regcache
*regcache
;
2985 struct gdbarch
*gdbarch
;
2986 struct thread_info
*tp
;
2988 struct address_space
*aspace
;
2990 struct execution_control_state ecss
;
2991 struct execution_control_state
*ecs
= &ecss
;
2992 struct cleanup
*old_chain
;
2993 struct cleanup
*defer_resume_cleanup
;
2996 /* If we're stopped at a fork/vfork, follow the branch set by the
2997 "set follow-fork-mode" command; otherwise, we'll just proceed
2998 resuming the current thread. */
2999 if (!follow_fork ())
3001 /* The target for some reason decided not to resume. */
3003 if (target_can_async_p ())
3004 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3008 /* We'll update this if & when we switch to a new thread. */
3009 previous_inferior_ptid
= inferior_ptid
;
3011 regcache
= get_current_regcache ();
3012 gdbarch
= get_regcache_arch (regcache
);
3013 aspace
= get_regcache_aspace (regcache
);
3014 pc
= regcache_read_pc (regcache
);
3015 tp
= inferior_thread ();
3017 /* Fill in with reasonable starting values. */
3018 init_thread_stepping_state (tp
);
3020 gdb_assert (!thread_is_in_step_over_chain (tp
));
3022 if (addr
== (CORE_ADDR
) -1)
3025 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3026 && execution_direction
!= EXEC_REVERSE
)
3027 /* There is a breakpoint at the address we will resume at,
3028 step one instruction before inserting breakpoints so that
3029 we do not stop right away (and report a second hit at this
3032 Note, we don't do this in reverse, because we won't
3033 actually be executing the breakpoint insn anyway.
3034 We'll be (un-)executing the previous instruction. */
3035 tp
->stepping_over_breakpoint
= 1;
3036 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3037 && gdbarch_single_step_through_delay (gdbarch
,
3038 get_current_frame ()))
3039 /* We stepped onto an instruction that needs to be stepped
3040 again before re-inserting the breakpoint, do so. */
3041 tp
->stepping_over_breakpoint
= 1;
3045 regcache_write_pc (regcache
, addr
);
3048 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3049 tp
->suspend
.stop_signal
= siggnal
;
3051 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3053 /* If an exception is thrown from this point on, make sure to
3054 propagate GDB's knowledge of the executing state to the
3055 frontend/user running state. */
3056 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3058 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3059 threads (e.g., we might need to set threads stepping over
3060 breakpoints first), from the user/frontend's point of view, all
3061 threads in RESUME_PTID are now running. Unless we're calling an
3062 inferior function, as in that case we pretend the inferior
3063 doesn't run at all. */
3064 if (!tp
->control
.in_infcall
)
3065 set_running (resume_ptid
, 1);
3068 fprintf_unfiltered (gdb_stdlog
,
3069 "infrun: proceed (addr=%s, signal=%s)\n",
3070 paddress (gdbarch
, addr
),
3071 gdb_signal_to_symbol_string (siggnal
));
3073 annotate_starting ();
3075 /* Make sure that output from GDB appears before output from the
3077 gdb_flush (gdb_stdout
);
3079 /* In a multi-threaded task we may select another thread and
3080 then continue or step.
3082 But if a thread that we're resuming had stopped at a breakpoint,
3083 it will immediately cause another breakpoint stop without any
3084 execution (i.e. it will report a breakpoint hit incorrectly). So
3085 we must step over it first.
3087 Look for threads other than the current (TP) that reported a
3088 breakpoint hit and haven't been resumed yet since. */
3090 /* If scheduler locking applies, we can avoid iterating over all
3092 if (!non_stop
&& !schedlock_applies (tp
))
3094 struct thread_info
*current
= tp
;
3096 ALL_NON_EXITED_THREADS (tp
)
3098 /* Ignore the current thread here. It's handled
3103 /* Ignore threads of processes we're not resuming. */
3104 if (!ptid_match (tp
->ptid
, resume_ptid
))
3107 if (!thread_still_needs_step_over (tp
))
3110 gdb_assert (!thread_is_in_step_over_chain (tp
));
3113 fprintf_unfiltered (gdb_stdlog
,
3114 "infrun: need to step-over [%s] first\n",
3115 target_pid_to_str (tp
->ptid
));
3117 thread_step_over_chain_enqueue (tp
);
3123 /* Enqueue the current thread last, so that we move all other
3124 threads over their breakpoints first. */
3125 if (tp
->stepping_over_breakpoint
)
3126 thread_step_over_chain_enqueue (tp
);
3128 /* If the thread isn't started, we'll still need to set its prev_pc,
3129 so that switch_back_to_stepped_thread knows the thread hasn't
3130 advanced. Must do this before resuming any thread, as in
3131 all-stop/remote, once we resume we can't send any other packet
3132 until the target stops again. */
3133 tp
->prev_pc
= regcache_read_pc (regcache
);
3135 defer_resume_cleanup
= make_cleanup_defer_target_commit_resume ();
3137 started
= start_step_over ();
3139 if (step_over_info_valid_p ())
3141 /* Either this thread started a new in-line step over, or some
3142 other thread was already doing one. In either case, don't
3143 resume anything else until the step-over is finished. */
3145 else if (started
&& !target_is_non_stop_p ())
3147 /* A new displaced stepping sequence was started. In all-stop,
3148 we can't talk to the target anymore until it next stops. */
3150 else if (!non_stop
&& target_is_non_stop_p ())
3152 /* In all-stop, but the target is always in non-stop mode.
3153 Start all other threads that are implicitly resumed too. */
3154 ALL_NON_EXITED_THREADS (tp
)
3156 /* Ignore threads of processes we're not resuming. */
3157 if (!ptid_match (tp
->ptid
, resume_ptid
))
3163 fprintf_unfiltered (gdb_stdlog
,
3164 "infrun: proceed: [%s] resumed\n",
3165 target_pid_to_str (tp
->ptid
));
3166 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3170 if (thread_is_in_step_over_chain (tp
))
3173 fprintf_unfiltered (gdb_stdlog
,
3174 "infrun: proceed: [%s] needs step-over\n",
3175 target_pid_to_str (tp
->ptid
));
3180 fprintf_unfiltered (gdb_stdlog
,
3181 "infrun: proceed: resuming %s\n",
3182 target_pid_to_str (tp
->ptid
));
3184 reset_ecs (ecs
, tp
);
3185 switch_to_thread (tp
->ptid
);
3186 keep_going_pass_signal (ecs
);
3187 if (!ecs
->wait_some_more
)
3188 error (_("Command aborted."));
3191 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3193 /* The thread wasn't started, and isn't queued, run it now. */
3194 reset_ecs (ecs
, tp
);
3195 switch_to_thread (tp
->ptid
);
3196 keep_going_pass_signal (ecs
);
3197 if (!ecs
->wait_some_more
)
3198 error (_("Command aborted."));
3201 do_cleanups (defer_resume_cleanup
);
3202 target_commit_resume ();
3204 discard_cleanups (old_chain
);
3206 /* Tell the event loop to wait for it to stop. If the target
3207 supports asynchronous execution, it'll do this from within
3209 if (!target_can_async_p ())
3210 mark_async_event_handler (infrun_async_inferior_event_token
);
3214 /* Start remote-debugging of a machine over a serial link. */
3217 start_remote (int from_tty
)
3219 struct inferior
*inferior
;
3221 inferior
= current_inferior ();
3222 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3224 /* Always go on waiting for the target, regardless of the mode. */
3225 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3226 indicate to wait_for_inferior that a target should timeout if
3227 nothing is returned (instead of just blocking). Because of this,
3228 targets expecting an immediate response need to, internally, set
3229 things up so that the target_wait() is forced to eventually
3231 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3232 differentiate to its caller what the state of the target is after
3233 the initial open has been performed. Here we're assuming that
3234 the target has stopped. It should be possible to eventually have
3235 target_open() return to the caller an indication that the target
3236 is currently running and GDB state should be set to the same as
3237 for an async run. */
3238 wait_for_inferior ();
3240 /* Now that the inferior has stopped, do any bookkeeping like
3241 loading shared libraries. We want to do this before normal_stop,
3242 so that the displayed frame is up to date. */
3243 post_create_inferior (¤t_target
, from_tty
);
3248 /* Initialize static vars when a new inferior begins. */
3251 init_wait_for_inferior (void)
3253 /* These are meaningless until the first time through wait_for_inferior. */
3255 breakpoint_init_inferior (inf_starting
);
3257 clear_proceed_status (0);
3259 target_last_wait_ptid
= minus_one_ptid
;
3261 previous_inferior_ptid
= inferior_ptid
;
3263 /* Discard any skipped inlined frames. */
3264 clear_inline_frame_state (minus_one_ptid
);
3269 static void handle_inferior_event (struct execution_control_state
*ecs
);
3271 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3272 struct execution_control_state
*ecs
);
3273 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3274 struct execution_control_state
*ecs
);
3275 static void handle_signal_stop (struct execution_control_state
*ecs
);
3276 static void check_exception_resume (struct execution_control_state
*,
3277 struct frame_info
*);
3279 static void end_stepping_range (struct execution_control_state
*ecs
);
3280 static void stop_waiting (struct execution_control_state
*ecs
);
3281 static void keep_going (struct execution_control_state
*ecs
);
3282 static void process_event_stop_test (struct execution_control_state
*ecs
);
3283 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3285 /* This function is attached as a "thread_stop_requested" observer.
3286 Cleanup local state that assumed the PTID was to be resumed, and
3287 report the stop to the frontend. */
3290 infrun_thread_stop_requested (ptid_t ptid
)
3292 struct thread_info
*tp
;
3294 /* PTID was requested to stop. If the thread was already stopped,
3295 but the user/frontend doesn't know about that yet (e.g., the
3296 thread had been temporarily paused for some step-over), set up
3297 for reporting the stop now. */
3298 ALL_NON_EXITED_THREADS (tp
)
3299 if (ptid_match (tp
->ptid
, ptid
))
3301 if (tp
->state
!= THREAD_RUNNING
)
3306 /* Remove matching threads from the step-over queue, so
3307 start_step_over doesn't try to resume them
3309 if (thread_is_in_step_over_chain (tp
))
3310 thread_step_over_chain_remove (tp
);
3312 /* If the thread is stopped, but the user/frontend doesn't
3313 know about that yet, queue a pending event, as if the
3314 thread had just stopped now. Unless the thread already had
3316 if (!tp
->suspend
.waitstatus_pending_p
)
3318 tp
->suspend
.waitstatus_pending_p
= 1;
3319 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_STOPPED
;
3320 tp
->suspend
.waitstatus
.value
.sig
= GDB_SIGNAL_0
;
3323 /* Clear the inline-frame state, since we're re-processing the
3325 clear_inline_frame_state (tp
->ptid
);
3327 /* If this thread was paused because some other thread was
3328 doing an inline-step over, let that finish first. Once
3329 that happens, we'll restart all threads and consume pending
3330 stop events then. */
3331 if (step_over_info_valid_p ())
3334 /* Otherwise we can process the (new) pending event now. Set
3335 it so this pending event is considered by
3342 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3344 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3345 nullify_last_target_wait_ptid ();
3348 /* Delete the step resume, single-step and longjmp/exception resume
3349 breakpoints of TP. */
3352 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3354 delete_step_resume_breakpoint (tp
);
3355 delete_exception_resume_breakpoint (tp
);
3356 delete_single_step_breakpoints (tp
);
3359 /* If the target still has execution, call FUNC for each thread that
3360 just stopped. In all-stop, that's all the non-exited threads; in
3361 non-stop, that's the current thread, only. */
3363 typedef void (*for_each_just_stopped_thread_callback_func
)
3364 (struct thread_info
*tp
);
3367 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3369 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3372 if (target_is_non_stop_p ())
3374 /* If in non-stop mode, only the current thread stopped. */
3375 func (inferior_thread ());
3379 struct thread_info
*tp
;
3381 /* In all-stop mode, all threads have stopped. */
3382 ALL_NON_EXITED_THREADS (tp
)
3389 /* Delete the step resume and longjmp/exception resume breakpoints of
3390 the threads that just stopped. */
3393 delete_just_stopped_threads_infrun_breakpoints (void)
3395 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3398 /* Delete the single-step breakpoints of the threads that just
3402 delete_just_stopped_threads_single_step_breakpoints (void)
3404 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3407 /* A cleanup wrapper. */
3410 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3412 delete_just_stopped_threads_infrun_breakpoints ();
3418 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3419 const struct target_waitstatus
*ws
)
3421 char *status_string
= target_waitstatus_to_string (ws
);
3424 /* The text is split over several lines because it was getting too long.
3425 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3426 output as a unit; we want only one timestamp printed if debug_timestamp
3429 stb
.printf ("infrun: target_wait (%d.%ld.%ld",
3430 ptid_get_pid (waiton_ptid
),
3431 ptid_get_lwp (waiton_ptid
),
3432 ptid_get_tid (waiton_ptid
));
3433 if (ptid_get_pid (waiton_ptid
) != -1)
3434 stb
.printf (" [%s]", target_pid_to_str (waiton_ptid
));
3435 stb
.printf (", status) =\n");
3436 stb
.printf ("infrun: %d.%ld.%ld [%s],\n",
3437 ptid_get_pid (result_ptid
),
3438 ptid_get_lwp (result_ptid
),
3439 ptid_get_tid (result_ptid
),
3440 target_pid_to_str (result_ptid
));
3441 stb
.printf ("infrun: %s\n", status_string
);
3443 /* This uses %s in part to handle %'s in the text, but also to avoid
3444 a gcc error: the format attribute requires a string literal. */
3445 fprintf_unfiltered (gdb_stdlog
, "%s", stb
.c_str ());
3447 xfree (status_string
);
3450 /* Select a thread at random, out of those which are resumed and have
3453 static struct thread_info
*
3454 random_pending_event_thread (ptid_t waiton_ptid
)
3456 struct thread_info
*event_tp
;
3458 int random_selector
;
3460 /* First see how many events we have. Count only resumed threads
3461 that have an event pending. */
3462 ALL_NON_EXITED_THREADS (event_tp
)
3463 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3464 && event_tp
->resumed
3465 && event_tp
->suspend
.waitstatus_pending_p
)
3468 if (num_events
== 0)
3471 /* Now randomly pick a thread out of those that have had events. */
3472 random_selector
= (int)
3473 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3475 if (debug_infrun
&& num_events
> 1)
3476 fprintf_unfiltered (gdb_stdlog
,
3477 "infrun: Found %d events, selecting #%d\n",
3478 num_events
, random_selector
);
3480 /* Select the Nth thread that has had an event. */
3481 ALL_NON_EXITED_THREADS (event_tp
)
3482 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3483 && event_tp
->resumed
3484 && event_tp
->suspend
.waitstatus_pending_p
)
3485 if (random_selector
-- == 0)
3491 /* Wrapper for target_wait that first checks whether threads have
3492 pending statuses to report before actually asking the target for
3496 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3499 struct thread_info
*tp
;
3501 /* First check if there is a resumed thread with a wait status
3503 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3505 tp
= random_pending_event_thread (ptid
);
3510 fprintf_unfiltered (gdb_stdlog
,
3511 "infrun: Waiting for specific thread %s.\n",
3512 target_pid_to_str (ptid
));
3514 /* We have a specific thread to check. */
3515 tp
= find_thread_ptid (ptid
);
3516 gdb_assert (tp
!= NULL
);
3517 if (!tp
->suspend
.waitstatus_pending_p
)
3522 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3523 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3525 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3526 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3530 pc
= regcache_read_pc (regcache
);
3532 if (pc
!= tp
->suspend
.stop_pc
)
3535 fprintf_unfiltered (gdb_stdlog
,
3536 "infrun: PC of %s changed. was=%s, now=%s\n",
3537 target_pid_to_str (tp
->ptid
),
3538 paddress (gdbarch
, tp
->prev_pc
),
3539 paddress (gdbarch
, pc
));
3542 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3545 fprintf_unfiltered (gdb_stdlog
,
3546 "infrun: previous breakpoint of %s, at %s gone\n",
3547 target_pid_to_str (tp
->ptid
),
3548 paddress (gdbarch
, pc
));
3556 fprintf_unfiltered (gdb_stdlog
,
3557 "infrun: pending event of %s cancelled.\n",
3558 target_pid_to_str (tp
->ptid
));
3560 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3561 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3571 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3572 fprintf_unfiltered (gdb_stdlog
,
3573 "infrun: Using pending wait status %s for %s.\n",
3575 target_pid_to_str (tp
->ptid
));
3579 /* Now that we've selected our final event LWP, un-adjust its PC
3580 if it was a software breakpoint (and the target doesn't
3581 always adjust the PC itself). */
3582 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3583 && !target_supports_stopped_by_sw_breakpoint ())
3585 struct regcache
*regcache
;
3586 struct gdbarch
*gdbarch
;
3589 regcache
= get_thread_regcache (tp
->ptid
);
3590 gdbarch
= get_regcache_arch (regcache
);
3592 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3597 pc
= regcache_read_pc (regcache
);
3598 regcache_write_pc (regcache
, pc
+ decr_pc
);
3602 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3603 *status
= tp
->suspend
.waitstatus
;
3604 tp
->suspend
.waitstatus_pending_p
= 0;
3606 /* Wake up the event loop again, until all pending events are
3608 if (target_is_async_p ())
3609 mark_async_event_handler (infrun_async_inferior_event_token
);
3613 /* But if we don't find one, we'll have to wait. */
3615 if (deprecated_target_wait_hook
)
3616 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3618 event_ptid
= target_wait (ptid
, status
, options
);
3623 /* Prepare and stabilize the inferior for detaching it. E.g.,
3624 detaching while a thread is displaced stepping is a recipe for
3625 crashing it, as nothing would readjust the PC out of the scratch
3629 prepare_for_detach (void)
3631 struct inferior
*inf
= current_inferior ();
3632 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3633 struct displaced_step_inferior_state
*displaced
;
3635 displaced
= get_displaced_stepping_state (inf
->pid
);
3637 /* Is any thread of this process displaced stepping? If not,
3638 there's nothing else to do. */
3639 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3643 fprintf_unfiltered (gdb_stdlog
,
3644 "displaced-stepping in-process while detaching");
3646 scoped_restore restore_detaching
= make_scoped_restore (&inf
->detaching
, true);
3648 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3650 struct cleanup
*old_chain_2
;
3651 struct execution_control_state ecss
;
3652 struct execution_control_state
*ecs
;
3655 memset (ecs
, 0, sizeof (*ecs
));
3657 overlay_cache_invalid
= 1;
3658 /* Flush target cache before starting to handle each event.
3659 Target was running and cache could be stale. This is just a
3660 heuristic. Running threads may modify target memory, but we
3661 don't get any event. */
3662 target_dcache_invalidate ();
3664 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3667 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3669 /* If an error happens while handling the event, propagate GDB's
3670 knowledge of the executing state to the frontend/user running
3672 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3675 /* Now figure out what to do with the result of the result. */
3676 handle_inferior_event (ecs
);
3678 /* No error, don't finish the state yet. */
3679 discard_cleanups (old_chain_2
);
3681 /* Breakpoints and watchpoints are not installed on the target
3682 at this point, and signals are passed directly to the
3683 inferior, so this must mean the process is gone. */
3684 if (!ecs
->wait_some_more
)
3686 restore_detaching
.release ();
3687 error (_("Program exited while detaching"));
3691 restore_detaching
.release ();
3694 /* Wait for control to return from inferior to debugger.
3696 If inferior gets a signal, we may decide to start it up again
3697 instead of returning. That is why there is a loop in this function.
3698 When this function actually returns it means the inferior
3699 should be left stopped and GDB should read more commands. */
3702 wait_for_inferior (void)
3704 struct cleanup
*old_cleanups
;
3705 struct cleanup
*thread_state_chain
;
3709 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3712 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3715 /* If an error happens while handling the event, propagate GDB's
3716 knowledge of the executing state to the frontend/user running
3718 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3722 struct execution_control_state ecss
;
3723 struct execution_control_state
*ecs
= &ecss
;
3724 ptid_t waiton_ptid
= minus_one_ptid
;
3726 memset (ecs
, 0, sizeof (*ecs
));
3728 overlay_cache_invalid
= 1;
3730 /* Flush target cache before starting to handle each event.
3731 Target was running and cache could be stale. This is just a
3732 heuristic. Running threads may modify target memory, but we
3733 don't get any event. */
3734 target_dcache_invalidate ();
3736 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3739 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3741 /* Now figure out what to do with the result of the result. */
3742 handle_inferior_event (ecs
);
3744 if (!ecs
->wait_some_more
)
3748 /* No error, don't finish the state yet. */
3749 discard_cleanups (thread_state_chain
);
3751 do_cleanups (old_cleanups
);
3754 /* Cleanup that reinstalls the readline callback handler, if the
3755 target is running in the background. If while handling the target
3756 event something triggered a secondary prompt, like e.g., a
3757 pagination prompt, we'll have removed the callback handler (see
3758 gdb_readline_wrapper_line). Need to do this as we go back to the
3759 event loop, ready to process further input. Note this has no
3760 effect if the handler hasn't actually been removed, because calling
3761 rl_callback_handler_install resets the line buffer, thus losing
3765 reinstall_readline_callback_handler_cleanup (void *arg
)
3767 struct ui
*ui
= current_ui
;
3771 /* We're not going back to the top level event loop yet. Don't
3772 install the readline callback, as it'd prep the terminal,
3773 readline-style (raw, noecho) (e.g., --batch). We'll install
3774 it the next time the prompt is displayed, when we're ready
3779 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3780 gdb_rl_callback_handler_reinstall ();
3783 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3784 that's just the event thread. In all-stop, that's all threads. */
3787 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3789 struct thread_info
*thr
= ecs
->event_thread
;
3791 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3792 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3796 ALL_NON_EXITED_THREADS (thr
)
3798 if (thr
->thread_fsm
== NULL
)
3800 if (thr
== ecs
->event_thread
)
3803 switch_to_thread (thr
->ptid
);
3804 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3807 if (ecs
->event_thread
!= NULL
)
3808 switch_to_thread (ecs
->event_thread
->ptid
);
3812 /* Helper for all_uis_check_sync_execution_done that works on the
3816 check_curr_ui_sync_execution_done (void)
3818 struct ui
*ui
= current_ui
;
3820 if (ui
->prompt_state
== PROMPT_NEEDED
3822 && !gdb_in_secondary_prompt_p (ui
))
3824 target_terminal_ours ();
3825 observer_notify_sync_execution_done ();
3826 ui_register_input_event_handler (ui
);
3833 all_uis_check_sync_execution_done (void)
3835 SWITCH_THRU_ALL_UIS ()
3837 check_curr_ui_sync_execution_done ();
3844 all_uis_on_sync_execution_starting (void)
3846 SWITCH_THRU_ALL_UIS ()
3848 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3849 async_disable_stdin ();
3853 /* Asynchronous version of wait_for_inferior. It is called by the
3854 event loop whenever a change of state is detected on the file
3855 descriptor corresponding to the target. It can be called more than
3856 once to complete a single execution command. In such cases we need
3857 to keep the state in a global variable ECSS. If it is the last time
3858 that this function is called for a single execution command, then
3859 report to the user that the inferior has stopped, and do the
3860 necessary cleanups. */
3863 fetch_inferior_event (void *client_data
)
3865 struct execution_control_state ecss
;
3866 struct execution_control_state
*ecs
= &ecss
;
3867 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3868 struct cleanup
*ts_old_chain
;
3870 ptid_t waiton_ptid
= minus_one_ptid
;
3872 memset (ecs
, 0, sizeof (*ecs
));
3874 /* Events are always processed with the main UI as current UI. This
3875 way, warnings, debug output, etc. are always consistently sent to
3876 the main console. */
3877 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3879 /* End up with readline processing input, if necessary. */
3880 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3882 /* We're handling a live event, so make sure we're doing live
3883 debugging. If we're looking at traceframes while the target is
3884 running, we're going to need to get back to that mode after
3885 handling the event. */
3888 make_cleanup_restore_current_traceframe ();
3889 set_current_traceframe (-1);
3892 gdb::optional
<scoped_restore_current_thread
> maybe_restore_thread
;
3895 /* In non-stop mode, the user/frontend should not notice a thread
3896 switch due to internal events. Make sure we reverse to the
3897 user selected thread and frame after handling the event and
3898 running any breakpoint commands. */
3899 maybe_restore_thread
.emplace ();
3901 overlay_cache_invalid
= 1;
3902 /* Flush target cache before starting to handle each event. Target
3903 was running and cache could be stale. This is just a heuristic.
3904 Running threads may modify target memory, but we don't get any
3906 target_dcache_invalidate ();
3908 scoped_restore save_exec_dir
3909 = make_scoped_restore (&execution_direction
, target_execution_direction ());
3911 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3912 target_can_async_p () ? TARGET_WNOHANG
: 0);
3915 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3917 /* If an error happens while handling the event, propagate GDB's
3918 knowledge of the executing state to the frontend/user running
3920 if (!target_is_non_stop_p ())
3921 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3923 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3925 /* Get executed before make_cleanup_restore_current_thread above to apply
3926 still for the thread which has thrown the exception. */
3927 make_bpstat_clear_actions_cleanup ();
3929 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3931 /* Now figure out what to do with the result of the result. */
3932 handle_inferior_event (ecs
);
3934 if (!ecs
->wait_some_more
)
3936 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3937 int should_stop
= 1;
3938 struct thread_info
*thr
= ecs
->event_thread
;
3939 int should_notify_stop
= 1;
3941 delete_just_stopped_threads_infrun_breakpoints ();
3945 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3947 if (thread_fsm
!= NULL
)
3948 should_stop
= thread_fsm_should_stop (thread_fsm
, thr
);
3957 clean_up_just_stopped_threads_fsms (ecs
);
3959 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3962 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
3965 if (should_notify_stop
)
3969 /* We may not find an inferior if this was a process exit. */
3970 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3971 proceeded
= normal_stop ();
3975 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3982 /* No error, don't finish the thread states yet. */
3983 discard_cleanups (ts_old_chain
);
3985 /* Revert thread and frame. */
3986 do_cleanups (old_chain
);
3988 /* If a UI was in sync execution mode, and now isn't, restore its
3989 prompt (a synchronous execution command has finished, and we're
3990 ready for input). */
3991 all_uis_check_sync_execution_done ();
3994 && exec_done_display_p
3995 && (ptid_equal (inferior_ptid
, null_ptid
)
3996 || !is_running (inferior_ptid
)))
3997 printf_unfiltered (_("completed.\n"));
4000 /* Record the frame and location we're currently stepping through. */
4002 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
4004 struct thread_info
*tp
= inferior_thread ();
4006 tp
->control
.step_frame_id
= get_frame_id (frame
);
4007 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4009 tp
->current_symtab
= sal
.symtab
;
4010 tp
->current_line
= sal
.line
;
4013 /* Clear context switchable stepping state. */
4016 init_thread_stepping_state (struct thread_info
*tss
)
4018 tss
->stepped_breakpoint
= 0;
4019 tss
->stepping_over_breakpoint
= 0;
4020 tss
->stepping_over_watchpoint
= 0;
4021 tss
->step_after_step_resume_breakpoint
= 0;
4024 /* Set the cached copy of the last ptid/waitstatus. */
4027 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
4029 target_last_wait_ptid
= ptid
;
4030 target_last_waitstatus
= status
;
4033 /* Return the cached copy of the last pid/waitstatus returned by
4034 target_wait()/deprecated_target_wait_hook(). The data is actually
4035 cached by handle_inferior_event(), which gets called immediately
4036 after target_wait()/deprecated_target_wait_hook(). */
4039 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
4041 *ptidp
= target_last_wait_ptid
;
4042 *status
= target_last_waitstatus
;
4046 nullify_last_target_wait_ptid (void)
4048 target_last_wait_ptid
= minus_one_ptid
;
4051 /* Switch thread contexts. */
4054 context_switch (ptid_t ptid
)
4056 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4058 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4059 target_pid_to_str (inferior_ptid
));
4060 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4061 target_pid_to_str (ptid
));
4064 switch_to_thread (ptid
);
4067 /* If the target can't tell whether we've hit breakpoints
4068 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4069 check whether that could have been caused by a breakpoint. If so,
4070 adjust the PC, per gdbarch_decr_pc_after_break. */
4073 adjust_pc_after_break (struct thread_info
*thread
,
4074 struct target_waitstatus
*ws
)
4076 struct regcache
*regcache
;
4077 struct gdbarch
*gdbarch
;
4078 struct address_space
*aspace
;
4079 CORE_ADDR breakpoint_pc
, decr_pc
;
4081 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4082 we aren't, just return.
4084 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4085 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4086 implemented by software breakpoints should be handled through the normal
4089 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4090 different signals (SIGILL or SIGEMT for instance), but it is less
4091 clear where the PC is pointing afterwards. It may not match
4092 gdbarch_decr_pc_after_break. I don't know any specific target that
4093 generates these signals at breakpoints (the code has been in GDB since at
4094 least 1992) so I can not guess how to handle them here.
4096 In earlier versions of GDB, a target with
4097 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4098 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4099 target with both of these set in GDB history, and it seems unlikely to be
4100 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4102 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4105 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4108 /* In reverse execution, when a breakpoint is hit, the instruction
4109 under it has already been de-executed. The reported PC always
4110 points at the breakpoint address, so adjusting it further would
4111 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4114 B1 0x08000000 : INSN1
4115 B2 0x08000001 : INSN2
4117 PC -> 0x08000003 : INSN4
4119 Say you're stopped at 0x08000003 as above. Reverse continuing
4120 from that point should hit B2 as below. Reading the PC when the
4121 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4122 been de-executed already.
4124 B1 0x08000000 : INSN1
4125 B2 PC -> 0x08000001 : INSN2
4129 We can't apply the same logic as for forward execution, because
4130 we would wrongly adjust the PC to 0x08000000, since there's a
4131 breakpoint at PC - 1. We'd then report a hit on B1, although
4132 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4134 if (execution_direction
== EXEC_REVERSE
)
4137 /* If the target can tell whether the thread hit a SW breakpoint,
4138 trust it. Targets that can tell also adjust the PC
4140 if (target_supports_stopped_by_sw_breakpoint ())
4143 /* Note that relying on whether a breakpoint is planted in memory to
4144 determine this can fail. E.g,. the breakpoint could have been
4145 removed since. Or the thread could have been told to step an
4146 instruction the size of a breakpoint instruction, and only
4147 _after_ was a breakpoint inserted at its address. */
4149 /* If this target does not decrement the PC after breakpoints, then
4150 we have nothing to do. */
4151 regcache
= get_thread_regcache (thread
->ptid
);
4152 gdbarch
= get_regcache_arch (regcache
);
4154 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4158 aspace
= get_regcache_aspace (regcache
);
4160 /* Find the location where (if we've hit a breakpoint) the
4161 breakpoint would be. */
4162 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4164 /* If the target can't tell whether a software breakpoint triggered,
4165 fallback to figuring it out based on breakpoints we think were
4166 inserted in the target, and on whether the thread was stepped or
4169 /* Check whether there actually is a software breakpoint inserted at
4172 If in non-stop mode, a race condition is possible where we've
4173 removed a breakpoint, but stop events for that breakpoint were
4174 already queued and arrive later. To suppress those spurious
4175 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4176 and retire them after a number of stop events are reported. Note
4177 this is an heuristic and can thus get confused. The real fix is
4178 to get the "stopped by SW BP and needs adjustment" info out of
4179 the target/kernel (and thus never reach here; see above). */
4180 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4181 || (target_is_non_stop_p ()
4182 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4184 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4186 if (record_full_is_used ())
4187 record_full_gdb_operation_disable_set ();
4189 /* When using hardware single-step, a SIGTRAP is reported for both
4190 a completed single-step and a software breakpoint. Need to
4191 differentiate between the two, as the latter needs adjusting
4192 but the former does not.
4194 The SIGTRAP can be due to a completed hardware single-step only if
4195 - we didn't insert software single-step breakpoints
4196 - this thread is currently being stepped
4198 If any of these events did not occur, we must have stopped due
4199 to hitting a software breakpoint, and have to back up to the
4202 As a special case, we could have hardware single-stepped a
4203 software breakpoint. In this case (prev_pc == breakpoint_pc),
4204 we also need to back up to the breakpoint address. */
4206 if (thread_has_single_step_breakpoints_set (thread
)
4207 || !currently_stepping (thread
)
4208 || (thread
->stepped_breakpoint
4209 && thread
->prev_pc
== breakpoint_pc
))
4210 regcache_write_pc (regcache
, breakpoint_pc
);
4212 do_cleanups (old_cleanups
);
4217 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4219 for (frame
= get_prev_frame (frame
);
4221 frame
= get_prev_frame (frame
))
4223 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4225 if (get_frame_type (frame
) != INLINE_FRAME
)
4232 /* If the event thread has the stop requested flag set, pretend it
4233 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4237 handle_stop_requested (struct execution_control_state
*ecs
)
4239 if (ecs
->event_thread
->stop_requested
)
4241 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4242 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4243 handle_signal_stop (ecs
);
4249 /* Auxiliary function that handles syscall entry/return events.
4250 It returns 1 if the inferior should keep going (and GDB
4251 should ignore the event), or 0 if the event deserves to be
4255 handle_syscall_event (struct execution_control_state
*ecs
)
4257 struct regcache
*regcache
;
4260 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4261 context_switch (ecs
->ptid
);
4263 regcache
= get_thread_regcache (ecs
->ptid
);
4264 syscall_number
= ecs
->ws
.value
.syscall_number
;
4265 stop_pc
= regcache_read_pc (regcache
);
4267 if (catch_syscall_enabled () > 0
4268 && catching_syscall_number (syscall_number
) > 0)
4271 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4274 ecs
->event_thread
->control
.stop_bpstat
4275 = bpstat_stop_status (get_regcache_aspace (regcache
),
4276 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4278 if (handle_stop_requested (ecs
))
4281 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4283 /* Catchpoint hit. */
4288 if (handle_stop_requested (ecs
))
4291 /* If no catchpoint triggered for this, then keep going. */
4296 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4299 fill_in_stop_func (struct gdbarch
*gdbarch
,
4300 struct execution_control_state
*ecs
)
4302 if (!ecs
->stop_func_filled_in
)
4304 /* Don't care about return value; stop_func_start and stop_func_name
4305 will both be 0 if it doesn't work. */
4306 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4307 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4308 ecs
->stop_func_start
4309 += gdbarch_deprecated_function_start_offset (gdbarch
);
4311 if (gdbarch_skip_entrypoint_p (gdbarch
))
4312 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4313 ecs
->stop_func_start
);
4315 ecs
->stop_func_filled_in
= 1;
4320 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4322 static enum stop_kind
4323 get_inferior_stop_soon (ptid_t ptid
)
4325 struct inferior
*inf
= find_inferior_ptid (ptid
);
4327 gdb_assert (inf
!= NULL
);
4328 return inf
->control
.stop_soon
;
4331 /* Wait for one event. Store the resulting waitstatus in WS, and
4332 return the event ptid. */
4335 wait_one (struct target_waitstatus
*ws
)
4338 ptid_t wait_ptid
= minus_one_ptid
;
4340 overlay_cache_invalid
= 1;
4342 /* Flush target cache before starting to handle each event.
4343 Target was running and cache could be stale. This is just a
4344 heuristic. Running threads may modify target memory, but we
4345 don't get any event. */
4346 target_dcache_invalidate ();
4348 if (deprecated_target_wait_hook
)
4349 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4351 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4354 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4359 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4360 instead of the current thread. */
4361 #define THREAD_STOPPED_BY(REASON) \
4363 thread_stopped_by_ ## REASON (ptid_t ptid) \
4365 scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid); \
4366 inferior_ptid = ptid; \
4368 return target_stopped_by_ ## REASON (); \
4371 /* Generate thread_stopped_by_watchpoint. */
4372 THREAD_STOPPED_BY (watchpoint
)
4373 /* Generate thread_stopped_by_sw_breakpoint. */
4374 THREAD_STOPPED_BY (sw_breakpoint
)
4375 /* Generate thread_stopped_by_hw_breakpoint. */
4376 THREAD_STOPPED_BY (hw_breakpoint
)
4378 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4381 switch_to_thread_cleanup (void *ptid_p
)
4383 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4385 switch_to_thread (ptid
);
4388 /* Save the thread's event and stop reason to process it later. */
4391 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4393 struct regcache
*regcache
;
4394 struct address_space
*aspace
;
4400 statstr
= target_waitstatus_to_string (ws
);
4401 fprintf_unfiltered (gdb_stdlog
,
4402 "infrun: saving status %s for %d.%ld.%ld\n",
4404 ptid_get_pid (tp
->ptid
),
4405 ptid_get_lwp (tp
->ptid
),
4406 ptid_get_tid (tp
->ptid
));
4410 /* Record for later. */
4411 tp
->suspend
.waitstatus
= *ws
;
4412 tp
->suspend
.waitstatus_pending_p
= 1;
4414 regcache
= get_thread_regcache (tp
->ptid
);
4415 aspace
= get_regcache_aspace (regcache
);
4417 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4418 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4420 CORE_ADDR pc
= regcache_read_pc (regcache
);
4422 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4424 if (thread_stopped_by_watchpoint (tp
->ptid
))
4426 tp
->suspend
.stop_reason
4427 = TARGET_STOPPED_BY_WATCHPOINT
;
4429 else if (target_supports_stopped_by_sw_breakpoint ()
4430 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4432 tp
->suspend
.stop_reason
4433 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4435 else if (target_supports_stopped_by_hw_breakpoint ()
4436 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4438 tp
->suspend
.stop_reason
4439 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4441 else if (!target_supports_stopped_by_hw_breakpoint ()
4442 && hardware_breakpoint_inserted_here_p (aspace
,
4445 tp
->suspend
.stop_reason
4446 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4448 else if (!target_supports_stopped_by_sw_breakpoint ()
4449 && software_breakpoint_inserted_here_p (aspace
,
4452 tp
->suspend
.stop_reason
4453 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4455 else if (!thread_has_single_step_breakpoints_set (tp
)
4456 && currently_stepping (tp
))
4458 tp
->suspend
.stop_reason
4459 = TARGET_STOPPED_BY_SINGLE_STEP
;
4464 /* A cleanup that disables thread create/exit events. */
4467 disable_thread_events (void *arg
)
4469 target_thread_events (0);
4475 stop_all_threads (void)
4477 /* We may need multiple passes to discover all threads. */
4481 struct cleanup
*old_chain
;
4483 gdb_assert (target_is_non_stop_p ());
4486 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4488 entry_ptid
= inferior_ptid
;
4489 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4491 target_thread_events (1);
4492 make_cleanup (disable_thread_events
, NULL
);
4494 /* Request threads to stop, and then wait for the stops. Because
4495 threads we already know about can spawn more threads while we're
4496 trying to stop them, and we only learn about new threads when we
4497 update the thread list, do this in a loop, and keep iterating
4498 until two passes find no threads that need to be stopped. */
4499 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4502 fprintf_unfiltered (gdb_stdlog
,
4503 "infrun: stop_all_threads, pass=%d, "
4504 "iterations=%d\n", pass
, iterations
);
4508 struct target_waitstatus ws
;
4510 struct thread_info
*t
;
4512 update_thread_list ();
4514 /* Go through all threads looking for threads that we need
4515 to tell the target to stop. */
4516 ALL_NON_EXITED_THREADS (t
)
4520 /* If already stopping, don't request a stop again.
4521 We just haven't seen the notification yet. */
4522 if (!t
->stop_requested
)
4525 fprintf_unfiltered (gdb_stdlog
,
4526 "infrun: %s executing, "
4528 target_pid_to_str (t
->ptid
));
4529 target_stop (t
->ptid
);
4530 t
->stop_requested
= 1;
4535 fprintf_unfiltered (gdb_stdlog
,
4536 "infrun: %s executing, "
4537 "already stopping\n",
4538 target_pid_to_str (t
->ptid
));
4541 if (t
->stop_requested
)
4547 fprintf_unfiltered (gdb_stdlog
,
4548 "infrun: %s not executing\n",
4549 target_pid_to_str (t
->ptid
));
4551 /* The thread may be not executing, but still be
4552 resumed with a pending status to process. */
4560 /* If we find new threads on the second iteration, restart
4561 over. We want to see two iterations in a row with all
4566 event_ptid
= wait_one (&ws
);
4567 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4569 /* All resumed threads exited. */
4571 else if (ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4572 || ws
.kind
== TARGET_WAITKIND_EXITED
4573 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4577 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4579 fprintf_unfiltered (gdb_stdlog
,
4580 "infrun: %s exited while "
4581 "stopping threads\n",
4582 target_pid_to_str (ptid
));
4587 struct inferior
*inf
;
4589 t
= find_thread_ptid (event_ptid
);
4591 t
= add_thread (event_ptid
);
4593 t
->stop_requested
= 0;
4596 t
->control
.may_range_step
= 0;
4598 /* This may be the first time we see the inferior report
4600 inf
= find_inferior_ptid (event_ptid
);
4601 if (inf
->needs_setup
)
4603 switch_to_thread_no_regs (t
);
4607 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4608 && ws
.value
.sig
== GDB_SIGNAL_0
)
4610 /* We caught the event that we intended to catch, so
4611 there's no event pending. */
4612 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4613 t
->suspend
.waitstatus_pending_p
= 0;
4615 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4617 /* Add it back to the step-over queue. */
4620 fprintf_unfiltered (gdb_stdlog
,
4621 "infrun: displaced-step of %s "
4622 "canceled: adding back to the "
4623 "step-over queue\n",
4624 target_pid_to_str (t
->ptid
));
4626 t
->control
.trap_expected
= 0;
4627 thread_step_over_chain_enqueue (t
);
4632 enum gdb_signal sig
;
4633 struct regcache
*regcache
;
4639 statstr
= target_waitstatus_to_string (&ws
);
4640 fprintf_unfiltered (gdb_stdlog
,
4641 "infrun: target_wait %s, saving "
4642 "status for %d.%ld.%ld\n",
4644 ptid_get_pid (t
->ptid
),
4645 ptid_get_lwp (t
->ptid
),
4646 ptid_get_tid (t
->ptid
));
4650 /* Record for later. */
4651 save_waitstatus (t
, &ws
);
4653 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4654 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4656 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4658 /* Add it back to the step-over queue. */
4659 t
->control
.trap_expected
= 0;
4660 thread_step_over_chain_enqueue (t
);
4663 regcache
= get_thread_regcache (t
->ptid
);
4664 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4668 fprintf_unfiltered (gdb_stdlog
,
4669 "infrun: saved stop_pc=%s for %s "
4670 "(currently_stepping=%d)\n",
4671 paddress (target_gdbarch (),
4672 t
->suspend
.stop_pc
),
4673 target_pid_to_str (t
->ptid
),
4674 currently_stepping (t
));
4681 do_cleanups (old_chain
);
4684 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4687 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4690 handle_no_resumed (struct execution_control_state
*ecs
)
4692 struct inferior
*inf
;
4693 struct thread_info
*thread
;
4695 if (target_can_async_p ())
4702 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4710 /* There were no unwaited-for children left in the target, but,
4711 we're not synchronously waiting for events either. Just
4715 fprintf_unfiltered (gdb_stdlog
,
4716 "infrun: TARGET_WAITKIND_NO_RESUMED "
4717 "(ignoring: bg)\n");
4718 prepare_to_wait (ecs
);
4723 /* Otherwise, if we were running a synchronous execution command, we
4724 may need to cancel it and give the user back the terminal.
4726 In non-stop mode, the target can't tell whether we've already
4727 consumed previous stop events, so it can end up sending us a
4728 no-resumed event like so:
4730 #0 - thread 1 is left stopped
4732 #1 - thread 2 is resumed and hits breakpoint
4733 -> TARGET_WAITKIND_STOPPED
4735 #2 - thread 3 is resumed and exits
4736 this is the last resumed thread, so
4737 -> TARGET_WAITKIND_NO_RESUMED
4739 #3 - gdb processes stop for thread 2 and decides to re-resume
4742 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4743 thread 2 is now resumed, so the event should be ignored.
4745 IOW, if the stop for thread 2 doesn't end a foreground command,
4746 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4747 event. But it could be that the event meant that thread 2 itself
4748 (or whatever other thread was the last resumed thread) exited.
4750 To address this we refresh the thread list and check whether we
4751 have resumed threads _now_. In the example above, this removes
4752 thread 3 from the thread list. If thread 2 was re-resumed, we
4753 ignore this event. If we find no thread resumed, then we cancel
4754 the synchronous command show "no unwaited-for " to the user. */
4755 update_thread_list ();
4757 ALL_NON_EXITED_THREADS (thread
)
4759 if (thread
->executing
4760 || thread
->suspend
.waitstatus_pending_p
)
4762 /* There were no unwaited-for children left in the target at
4763 some point, but there are now. Just ignore. */
4765 fprintf_unfiltered (gdb_stdlog
,
4766 "infrun: TARGET_WAITKIND_NO_RESUMED "
4767 "(ignoring: found resumed)\n");
4768 prepare_to_wait (ecs
);
4773 /* Note however that we may find no resumed thread because the whole
4774 process exited meanwhile (thus updating the thread list results
4775 in an empty thread list). In this case we know we'll be getting
4776 a process exit event shortly. */
4782 thread
= any_live_thread_of_process (inf
->pid
);
4786 fprintf_unfiltered (gdb_stdlog
,
4787 "infrun: TARGET_WAITKIND_NO_RESUMED "
4788 "(expect process exit)\n");
4789 prepare_to_wait (ecs
);
4794 /* Go ahead and report the event. */
4798 /* Given an execution control state that has been freshly filled in by
4799 an event from the inferior, figure out what it means and take
4802 The alternatives are:
4804 1) stop_waiting and return; to really stop and return to the
4807 2) keep_going and return; to wait for the next event (set
4808 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4812 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4814 enum stop_kind stop_soon
;
4816 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4818 /* We had an event in the inferior, but we are not interested in
4819 handling it at this level. The lower layers have already
4820 done what needs to be done, if anything.
4822 One of the possible circumstances for this is when the
4823 inferior produces output for the console. The inferior has
4824 not stopped, and we are ignoring the event. Another possible
4825 circumstance is any event which the lower level knows will be
4826 reported multiple times without an intervening resume. */
4828 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4829 prepare_to_wait (ecs
);
4833 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4836 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4837 prepare_to_wait (ecs
);
4841 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4842 && handle_no_resumed (ecs
))
4845 /* Cache the last pid/waitstatus. */
4846 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4848 /* Always clear state belonging to the previous time we stopped. */
4849 stop_stack_dummy
= STOP_NONE
;
4851 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4853 /* No unwaited-for children left. IOW, all resumed children
4856 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4858 stop_print_frame
= 0;
4863 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4864 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4866 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4867 /* If it's a new thread, add it to the thread database. */
4868 if (ecs
->event_thread
== NULL
)
4869 ecs
->event_thread
= add_thread (ecs
->ptid
);
4871 /* Disable range stepping. If the next step request could use a
4872 range, this will be end up re-enabled then. */
4873 ecs
->event_thread
->control
.may_range_step
= 0;
4876 /* Dependent on valid ECS->EVENT_THREAD. */
4877 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4879 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4880 reinit_frame_cache ();
4882 breakpoint_retire_moribund ();
4884 /* First, distinguish signals caused by the debugger from signals
4885 that have to do with the program's own actions. Note that
4886 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4887 on the operating system version. Here we detect when a SIGILL or
4888 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4889 something similar for SIGSEGV, since a SIGSEGV will be generated
4890 when we're trying to execute a breakpoint instruction on a
4891 non-executable stack. This happens for call dummy breakpoints
4892 for architectures like SPARC that place call dummies on the
4894 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4895 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4896 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4897 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4899 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4901 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4902 regcache_read_pc (regcache
)))
4905 fprintf_unfiltered (gdb_stdlog
,
4906 "infrun: Treating signal as SIGTRAP\n");
4907 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4911 /* Mark the non-executing threads accordingly. In all-stop, all
4912 threads of all processes are stopped when we get any event
4913 reported. In non-stop mode, only the event thread stops. */
4917 if (!target_is_non_stop_p ())
4918 mark_ptid
= minus_one_ptid
;
4919 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4920 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4922 /* If we're handling a process exit in non-stop mode, even
4923 though threads haven't been deleted yet, one would think
4924 that there is nothing to do, as threads of the dead process
4925 will be soon deleted, and threads of any other process were
4926 left running. However, on some targets, threads survive a
4927 process exit event. E.g., for the "checkpoint" command,
4928 when the current checkpoint/fork exits, linux-fork.c
4929 automatically switches to another fork from within
4930 target_mourn_inferior, by associating the same
4931 inferior/thread to another fork. We haven't mourned yet at
4932 this point, but we must mark any threads left in the
4933 process as not-executing so that finish_thread_state marks
4934 them stopped (in the user's perspective) if/when we present
4935 the stop to the user. */
4936 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4939 mark_ptid
= ecs
->ptid
;
4941 set_executing (mark_ptid
, 0);
4943 /* Likewise the resumed flag. */
4944 set_resumed (mark_ptid
, 0);
4947 switch (ecs
->ws
.kind
)
4949 case TARGET_WAITKIND_LOADED
:
4951 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4952 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4953 context_switch (ecs
->ptid
);
4954 /* Ignore gracefully during startup of the inferior, as it might
4955 be the shell which has just loaded some objects, otherwise
4956 add the symbols for the newly loaded objects. Also ignore at
4957 the beginning of an attach or remote session; we will query
4958 the full list of libraries once the connection is
4961 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4962 if (stop_soon
== NO_STOP_QUIETLY
)
4964 struct regcache
*regcache
;
4966 regcache
= get_thread_regcache (ecs
->ptid
);
4968 handle_solib_event ();
4970 ecs
->event_thread
->control
.stop_bpstat
4971 = bpstat_stop_status (get_regcache_aspace (regcache
),
4972 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4974 if (handle_stop_requested (ecs
))
4977 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4979 /* A catchpoint triggered. */
4980 process_event_stop_test (ecs
);
4984 /* If requested, stop when the dynamic linker notifies
4985 gdb of events. This allows the user to get control
4986 and place breakpoints in initializer routines for
4987 dynamically loaded objects (among other things). */
4988 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4989 if (stop_on_solib_events
)
4991 /* Make sure we print "Stopped due to solib-event" in
4993 stop_print_frame
= 1;
5000 /* If we are skipping through a shell, or through shared library
5001 loading that we aren't interested in, resume the program. If
5002 we're running the program normally, also resume. */
5003 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5005 /* Loading of shared libraries might have changed breakpoint
5006 addresses. Make sure new breakpoints are inserted. */
5007 if (stop_soon
== NO_STOP_QUIETLY
)
5008 insert_breakpoints ();
5009 resume (GDB_SIGNAL_0
);
5010 prepare_to_wait (ecs
);
5014 /* But stop if we're attaching or setting up a remote
5016 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5017 || stop_soon
== STOP_QUIETLY_REMOTE
)
5020 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5025 internal_error (__FILE__
, __LINE__
,
5026 _("unhandled stop_soon: %d"), (int) stop_soon
);
5028 case TARGET_WAITKIND_SPURIOUS
:
5030 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5031 if (handle_stop_requested (ecs
))
5033 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5034 context_switch (ecs
->ptid
);
5035 resume (GDB_SIGNAL_0
);
5036 prepare_to_wait (ecs
);
5039 case TARGET_WAITKIND_THREAD_CREATED
:
5041 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5042 if (handle_stop_requested (ecs
))
5044 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5045 context_switch (ecs
->ptid
);
5046 if (!switch_back_to_stepped_thread (ecs
))
5050 case TARGET_WAITKIND_EXITED
:
5051 case TARGET_WAITKIND_SIGNALLED
:
5054 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5055 fprintf_unfiltered (gdb_stdlog
,
5056 "infrun: TARGET_WAITKIND_EXITED\n");
5058 fprintf_unfiltered (gdb_stdlog
,
5059 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5062 inferior_ptid
= ecs
->ptid
;
5063 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
5064 set_current_program_space (current_inferior ()->pspace
);
5065 handle_vfork_child_exec_or_exit (0);
5066 target_terminal_ours (); /* Must do this before mourn anyway. */
5068 /* Clearing any previous state of convenience variables. */
5069 clear_exit_convenience_vars ();
5071 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5073 /* Record the exit code in the convenience variable $_exitcode, so
5074 that the user can inspect this again later. */
5075 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5076 (LONGEST
) ecs
->ws
.value
.integer
);
5078 /* Also record this in the inferior itself. */
5079 current_inferior ()->has_exit_code
= 1;
5080 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5082 /* Support the --return-child-result option. */
5083 return_child_result_value
= ecs
->ws
.value
.integer
;
5085 observer_notify_exited (ecs
->ws
.value
.integer
);
5089 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5090 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5092 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5094 /* Set the value of the internal variable $_exitsignal,
5095 which holds the signal uncaught by the inferior. */
5096 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5097 gdbarch_gdb_signal_to_target (gdbarch
,
5098 ecs
->ws
.value
.sig
));
5102 /* We don't have access to the target's method used for
5103 converting between signal numbers (GDB's internal
5104 representation <-> target's representation).
5105 Therefore, we cannot do a good job at displaying this
5106 information to the user. It's better to just warn
5107 her about it (if infrun debugging is enabled), and
5110 fprintf_filtered (gdb_stdlog
, _("\
5111 Cannot fill $_exitsignal with the correct signal number.\n"));
5114 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
5117 gdb_flush (gdb_stdout
);
5118 target_mourn_inferior (inferior_ptid
);
5119 stop_print_frame
= 0;
5123 /* The following are the only cases in which we keep going;
5124 the above cases end in a continue or goto. */
5125 case TARGET_WAITKIND_FORKED
:
5126 case TARGET_WAITKIND_VFORKED
:
5129 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5130 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
5132 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
5135 /* Check whether the inferior is displaced stepping. */
5137 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5138 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5140 /* If checking displaced stepping is supported, and thread
5141 ecs->ptid is displaced stepping. */
5142 if (displaced_step_in_progress_thread (ecs
->ptid
))
5144 struct inferior
*parent_inf
5145 = find_inferior_ptid (ecs
->ptid
);
5146 struct regcache
*child_regcache
;
5147 CORE_ADDR parent_pc
;
5149 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5150 indicating that the displaced stepping of syscall instruction
5151 has been done. Perform cleanup for parent process here. Note
5152 that this operation also cleans up the child process for vfork,
5153 because their pages are shared. */
5154 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
5155 /* Start a new step-over in another thread if there's one
5159 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5161 struct displaced_step_inferior_state
*displaced
5162 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
5164 /* Restore scratch pad for child process. */
5165 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
5168 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5169 the child's PC is also within the scratchpad. Set the child's PC
5170 to the parent's PC value, which has already been fixed up.
5171 FIXME: we use the parent's aspace here, although we're touching
5172 the child, because the child hasn't been added to the inferior
5173 list yet at this point. */
5176 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
5178 parent_inf
->aspace
);
5179 /* Read PC value of parent process. */
5180 parent_pc
= regcache_read_pc (regcache
);
5182 if (debug_displaced
)
5183 fprintf_unfiltered (gdb_stdlog
,
5184 "displaced: write child pc from %s to %s\n",
5186 regcache_read_pc (child_regcache
)),
5187 paddress (gdbarch
, parent_pc
));
5189 regcache_write_pc (child_regcache
, parent_pc
);
5193 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5194 context_switch (ecs
->ptid
);
5196 /* Immediately detach breakpoints from the child before there's
5197 any chance of letting the user delete breakpoints from the
5198 breakpoint lists. If we don't do this early, it's easy to
5199 leave left over traps in the child, vis: "break foo; catch
5200 fork; c; <fork>; del; c; <child calls foo>". We only follow
5201 the fork on the last `continue', and by that time the
5202 breakpoint at "foo" is long gone from the breakpoint table.
5203 If we vforked, then we don't need to unpatch here, since both
5204 parent and child are sharing the same memory pages; we'll
5205 need to unpatch at follow/detach time instead to be certain
5206 that new breakpoints added between catchpoint hit time and
5207 vfork follow are detached. */
5208 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5210 /* This won't actually modify the breakpoint list, but will
5211 physically remove the breakpoints from the child. */
5212 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5215 delete_just_stopped_threads_single_step_breakpoints ();
5217 /* In case the event is caught by a catchpoint, remember that
5218 the event is to be followed at the next resume of the thread,
5219 and not immediately. */
5220 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5222 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5224 ecs
->event_thread
->control
.stop_bpstat
5225 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5226 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5228 if (handle_stop_requested (ecs
))
5231 /* If no catchpoint triggered for this, then keep going. Note
5232 that we're interested in knowing the bpstat actually causes a
5233 stop, not just if it may explain the signal. Software
5234 watchpoints, for example, always appear in the bpstat. */
5235 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5241 = (follow_fork_mode_string
== follow_fork_mode_child
);
5243 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5245 should_resume
= follow_fork ();
5248 child
= ecs
->ws
.value
.related_pid
;
5250 /* At this point, the parent is marked running, and the
5251 child is marked stopped. */
5253 /* If not resuming the parent, mark it stopped. */
5254 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5255 set_running (parent
, 0);
5257 /* If resuming the child, mark it running. */
5258 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5259 set_running (child
, 1);
5261 /* In non-stop mode, also resume the other branch. */
5262 if (!detach_fork
&& (non_stop
5263 || (sched_multi
&& target_is_non_stop_p ())))
5266 switch_to_thread (parent
);
5268 switch_to_thread (child
);
5270 ecs
->event_thread
= inferior_thread ();
5271 ecs
->ptid
= inferior_ptid
;
5276 switch_to_thread (child
);
5278 switch_to_thread (parent
);
5280 ecs
->event_thread
= inferior_thread ();
5281 ecs
->ptid
= inferior_ptid
;
5289 process_event_stop_test (ecs
);
5292 case TARGET_WAITKIND_VFORK_DONE
:
5293 /* Done with the shared memory region. Re-insert breakpoints in
5294 the parent, and keep going. */
5297 fprintf_unfiltered (gdb_stdlog
,
5298 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5300 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5301 context_switch (ecs
->ptid
);
5303 current_inferior ()->waiting_for_vfork_done
= 0;
5304 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5306 if (handle_stop_requested (ecs
))
5309 /* This also takes care of reinserting breakpoints in the
5310 previously locked inferior. */
5314 case TARGET_WAITKIND_EXECD
:
5316 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5318 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5319 context_switch (ecs
->ptid
);
5321 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5323 /* Do whatever is necessary to the parent branch of the vfork. */
5324 handle_vfork_child_exec_or_exit (1);
5326 /* This causes the eventpoints and symbol table to be reset.
5327 Must do this now, before trying to determine whether to
5329 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5331 /* In follow_exec we may have deleted the original thread and
5332 created a new one. Make sure that the event thread is the
5333 execd thread for that case (this is a nop otherwise). */
5334 ecs
->event_thread
= inferior_thread ();
5336 ecs
->event_thread
->control
.stop_bpstat
5337 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5338 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5340 /* Note that this may be referenced from inside
5341 bpstat_stop_status above, through inferior_has_execd. */
5342 xfree (ecs
->ws
.value
.execd_pathname
);
5343 ecs
->ws
.value
.execd_pathname
= NULL
;
5345 if (handle_stop_requested (ecs
))
5348 /* If no catchpoint triggered for this, then keep going. */
5349 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5351 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5355 process_event_stop_test (ecs
);
5358 /* Be careful not to try to gather much state about a thread
5359 that's in a syscall. It's frequently a losing proposition. */
5360 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5362 fprintf_unfiltered (gdb_stdlog
,
5363 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5364 /* Getting the current syscall number. */
5365 if (handle_syscall_event (ecs
) == 0)
5366 process_event_stop_test (ecs
);
5369 /* Before examining the threads further, step this thread to
5370 get it entirely out of the syscall. (We get notice of the
5371 event when the thread is just on the verge of exiting a
5372 syscall. Stepping one instruction seems to get it back
5374 case TARGET_WAITKIND_SYSCALL_RETURN
:
5376 fprintf_unfiltered (gdb_stdlog
,
5377 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5378 if (handle_syscall_event (ecs
) == 0)
5379 process_event_stop_test (ecs
);
5382 case TARGET_WAITKIND_STOPPED
:
5384 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5385 handle_signal_stop (ecs
);
5388 case TARGET_WAITKIND_NO_HISTORY
:
5390 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5391 /* Reverse execution: target ran out of history info. */
5393 /* Switch to the stopped thread. */
5394 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5395 context_switch (ecs
->ptid
);
5397 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5399 delete_just_stopped_threads_single_step_breakpoints ();
5400 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5402 if (handle_stop_requested (ecs
))
5405 observer_notify_no_history ();
5411 /* A wrapper around handle_inferior_event_1, which also makes sure
5412 that all temporary struct value objects that were created during
5413 the handling of the event get deleted at the end. */
5416 handle_inferior_event (struct execution_control_state
*ecs
)
5418 struct value
*mark
= value_mark ();
5420 handle_inferior_event_1 (ecs
);
5421 /* Purge all temporary values created during the event handling,
5422 as it could be a long time before we return to the command level
5423 where such values would otherwise be purged. */
5424 value_free_to_mark (mark
);
5427 /* Restart threads back to what they were trying to do back when we
5428 paused them for an in-line step-over. The EVENT_THREAD thread is
5432 restart_threads (struct thread_info
*event_thread
)
5434 struct thread_info
*tp
;
5436 /* In case the instruction just stepped spawned a new thread. */
5437 update_thread_list ();
5439 ALL_NON_EXITED_THREADS (tp
)
5441 if (tp
== event_thread
)
5444 fprintf_unfiltered (gdb_stdlog
,
5445 "infrun: restart threads: "
5446 "[%s] is event thread\n",
5447 target_pid_to_str (tp
->ptid
));
5451 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5454 fprintf_unfiltered (gdb_stdlog
,
5455 "infrun: restart threads: "
5456 "[%s] not meant to be running\n",
5457 target_pid_to_str (tp
->ptid
));
5464 fprintf_unfiltered (gdb_stdlog
,
5465 "infrun: restart threads: [%s] resumed\n",
5466 target_pid_to_str (tp
->ptid
));
5467 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5471 if (thread_is_in_step_over_chain (tp
))
5474 fprintf_unfiltered (gdb_stdlog
,
5475 "infrun: restart threads: "
5476 "[%s] needs step-over\n",
5477 target_pid_to_str (tp
->ptid
));
5478 gdb_assert (!tp
->resumed
);
5483 if (tp
->suspend
.waitstatus_pending_p
)
5486 fprintf_unfiltered (gdb_stdlog
,
5487 "infrun: restart threads: "
5488 "[%s] has pending status\n",
5489 target_pid_to_str (tp
->ptid
));
5494 gdb_assert (!tp
->stop_requested
);
5496 /* If some thread needs to start a step-over at this point, it
5497 should still be in the step-over queue, and thus skipped
5499 if (thread_still_needs_step_over (tp
))
5501 internal_error (__FILE__
, __LINE__
,
5502 "thread [%s] needs a step-over, but not in "
5503 "step-over queue\n",
5504 target_pid_to_str (tp
->ptid
));
5507 if (currently_stepping (tp
))
5510 fprintf_unfiltered (gdb_stdlog
,
5511 "infrun: restart threads: [%s] was stepping\n",
5512 target_pid_to_str (tp
->ptid
));
5513 keep_going_stepped_thread (tp
);
5517 struct execution_control_state ecss
;
5518 struct execution_control_state
*ecs
= &ecss
;
5521 fprintf_unfiltered (gdb_stdlog
,
5522 "infrun: restart threads: [%s] continuing\n",
5523 target_pid_to_str (tp
->ptid
));
5524 reset_ecs (ecs
, tp
);
5525 switch_to_thread (tp
->ptid
);
5526 keep_going_pass_signal (ecs
);
5531 /* Callback for iterate_over_threads. Find a resumed thread that has
5532 a pending waitstatus. */
5535 resumed_thread_with_pending_status (struct thread_info
*tp
,
5539 && tp
->suspend
.waitstatus_pending_p
);
5542 /* Called when we get an event that may finish an in-line or
5543 out-of-line (displaced stepping) step-over started previously.
5544 Return true if the event is processed and we should go back to the
5545 event loop; false if the caller should continue processing the
5549 finish_step_over (struct execution_control_state
*ecs
)
5551 int had_step_over_info
;
5553 displaced_step_fixup (ecs
->ptid
,
5554 ecs
->event_thread
->suspend
.stop_signal
);
5556 had_step_over_info
= step_over_info_valid_p ();
5558 if (had_step_over_info
)
5560 /* If we're stepping over a breakpoint with all threads locked,
5561 then only the thread that was stepped should be reporting
5563 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5565 clear_step_over_info ();
5568 if (!target_is_non_stop_p ())
5571 /* Start a new step-over in another thread if there's one that
5575 /* If we were stepping over a breakpoint before, and haven't started
5576 a new in-line step-over sequence, then restart all other threads
5577 (except the event thread). We can't do this in all-stop, as then
5578 e.g., we wouldn't be able to issue any other remote packet until
5579 these other threads stop. */
5580 if (had_step_over_info
&& !step_over_info_valid_p ())
5582 struct thread_info
*pending
;
5584 /* If we only have threads with pending statuses, the restart
5585 below won't restart any thread and so nothing re-inserts the
5586 breakpoint we just stepped over. But we need it inserted
5587 when we later process the pending events, otherwise if
5588 another thread has a pending event for this breakpoint too,
5589 we'd discard its event (because the breakpoint that
5590 originally caused the event was no longer inserted). */
5591 context_switch (ecs
->ptid
);
5592 insert_breakpoints ();
5594 restart_threads (ecs
->event_thread
);
5596 /* If we have events pending, go through handle_inferior_event
5597 again, picking up a pending event at random. This avoids
5598 thread starvation. */
5600 /* But not if we just stepped over a watchpoint in order to let
5601 the instruction execute so we can evaluate its expression.
5602 The set of watchpoints that triggered is recorded in the
5603 breakpoint objects themselves (see bp->watchpoint_triggered).
5604 If we processed another event first, that other event could
5605 clobber this info. */
5606 if (ecs
->event_thread
->stepping_over_watchpoint
)
5609 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5611 if (pending
!= NULL
)
5613 struct thread_info
*tp
= ecs
->event_thread
;
5614 struct regcache
*regcache
;
5618 fprintf_unfiltered (gdb_stdlog
,
5619 "infrun: found resumed threads with "
5620 "pending events, saving status\n");
5623 gdb_assert (pending
!= tp
);
5625 /* Record the event thread's event for later. */
5626 save_waitstatus (tp
, &ecs
->ws
);
5627 /* This was cleared early, by handle_inferior_event. Set it
5628 so this pending event is considered by
5632 gdb_assert (!tp
->executing
);
5634 regcache
= get_thread_regcache (tp
->ptid
);
5635 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5639 fprintf_unfiltered (gdb_stdlog
,
5640 "infrun: saved stop_pc=%s for %s "
5641 "(currently_stepping=%d)\n",
5642 paddress (target_gdbarch (),
5643 tp
->suspend
.stop_pc
),
5644 target_pid_to_str (tp
->ptid
),
5645 currently_stepping (tp
));
5648 /* This in-line step-over finished; clear this so we won't
5649 start a new one. This is what handle_signal_stop would
5650 do, if we returned false. */
5651 tp
->stepping_over_breakpoint
= 0;
5653 /* Wake up the event loop again. */
5654 mark_async_event_handler (infrun_async_inferior_event_token
);
5656 prepare_to_wait (ecs
);
5664 /* Come here when the program has stopped with a signal. */
5667 handle_signal_stop (struct execution_control_state
*ecs
)
5669 struct frame_info
*frame
;
5670 struct gdbarch
*gdbarch
;
5671 int stopped_by_watchpoint
;
5672 enum stop_kind stop_soon
;
5675 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5677 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5679 /* Do we need to clean up the state of a thread that has
5680 completed a displaced single-step? (Doing so usually affects
5681 the PC, so do it here, before we set stop_pc.) */
5682 if (finish_step_over (ecs
))
5685 /* If we either finished a single-step or hit a breakpoint, but
5686 the user wanted this thread to be stopped, pretend we got a
5687 SIG0 (generic unsignaled stop). */
5688 if (ecs
->event_thread
->stop_requested
5689 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5690 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5692 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5696 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5697 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5698 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
5700 inferior_ptid
= ecs
->ptid
;
5702 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5703 paddress (gdbarch
, stop_pc
));
5704 if (target_stopped_by_watchpoint ())
5708 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5710 if (target_stopped_data_address (¤t_target
, &addr
))
5711 fprintf_unfiltered (gdb_stdlog
,
5712 "infrun: stopped data address = %s\n",
5713 paddress (gdbarch
, addr
));
5715 fprintf_unfiltered (gdb_stdlog
,
5716 "infrun: (no data address available)\n");
5720 /* This is originated from start_remote(), start_inferior() and
5721 shared libraries hook functions. */
5722 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5723 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5725 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5726 context_switch (ecs
->ptid
);
5728 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5729 stop_print_frame
= 1;
5734 /* This originates from attach_command(). We need to overwrite
5735 the stop_signal here, because some kernels don't ignore a
5736 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5737 See more comments in inferior.h. On the other hand, if we
5738 get a non-SIGSTOP, report it to the user - assume the backend
5739 will handle the SIGSTOP if it should show up later.
5741 Also consider that the attach is complete when we see a
5742 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5743 target extended-remote report it instead of a SIGSTOP
5744 (e.g. gdbserver). We already rely on SIGTRAP being our
5745 signal, so this is no exception.
5747 Also consider that the attach is complete when we see a
5748 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5749 the target to stop all threads of the inferior, in case the
5750 low level attach operation doesn't stop them implicitly. If
5751 they weren't stopped implicitly, then the stub will report a
5752 GDB_SIGNAL_0, meaning: stopped for no particular reason
5753 other than GDB's request. */
5754 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5755 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5756 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5757 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5759 stop_print_frame
= 1;
5761 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5765 /* See if something interesting happened to the non-current thread. If
5766 so, then switch to that thread. */
5767 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5770 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5772 context_switch (ecs
->ptid
);
5774 if (deprecated_context_hook
)
5775 deprecated_context_hook (ptid_to_global_thread_id (ecs
->ptid
));
5778 /* At this point, get hold of the now-current thread's frame. */
5779 frame
= get_current_frame ();
5780 gdbarch
= get_frame_arch (frame
);
5782 /* Pull the single step breakpoints out of the target. */
5783 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5785 struct regcache
*regcache
;
5786 struct address_space
*aspace
;
5789 regcache
= get_thread_regcache (ecs
->ptid
);
5790 aspace
= get_regcache_aspace (regcache
);
5791 pc
= regcache_read_pc (regcache
);
5793 /* However, before doing so, if this single-step breakpoint was
5794 actually for another thread, set this thread up for moving
5796 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5799 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5803 fprintf_unfiltered (gdb_stdlog
,
5804 "infrun: [%s] hit another thread's "
5805 "single-step breakpoint\n",
5806 target_pid_to_str (ecs
->ptid
));
5808 ecs
->hit_singlestep_breakpoint
= 1;
5815 fprintf_unfiltered (gdb_stdlog
,
5816 "infrun: [%s] hit its "
5817 "single-step breakpoint\n",
5818 target_pid_to_str (ecs
->ptid
));
5822 delete_just_stopped_threads_single_step_breakpoints ();
5824 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5825 && ecs
->event_thread
->control
.trap_expected
5826 && ecs
->event_thread
->stepping_over_watchpoint
)
5827 stopped_by_watchpoint
= 0;
5829 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5831 /* If necessary, step over this watchpoint. We'll be back to display
5833 if (stopped_by_watchpoint
5834 && (target_have_steppable_watchpoint
5835 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5837 /* At this point, we are stopped at an instruction which has
5838 attempted to write to a piece of memory under control of
5839 a watchpoint. The instruction hasn't actually executed
5840 yet. If we were to evaluate the watchpoint expression
5841 now, we would get the old value, and therefore no change
5842 would seem to have occurred.
5844 In order to make watchpoints work `right', we really need
5845 to complete the memory write, and then evaluate the
5846 watchpoint expression. We do this by single-stepping the
5849 It may not be necessary to disable the watchpoint to step over
5850 it. For example, the PA can (with some kernel cooperation)
5851 single step over a watchpoint without disabling the watchpoint.
5853 It is far more common to need to disable a watchpoint to step
5854 the inferior over it. If we have non-steppable watchpoints,
5855 we must disable the current watchpoint; it's simplest to
5856 disable all watchpoints.
5858 Any breakpoint at PC must also be stepped over -- if there's
5859 one, it will have already triggered before the watchpoint
5860 triggered, and we either already reported it to the user, or
5861 it didn't cause a stop and we called keep_going. In either
5862 case, if there was a breakpoint at PC, we must be trying to
5864 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5869 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5870 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5871 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5872 ecs
->event_thread
->control
.stop_step
= 0;
5873 stop_print_frame
= 1;
5874 stopped_by_random_signal
= 0;
5876 /* Hide inlined functions starting here, unless we just performed stepi or
5877 nexti. After stepi and nexti, always show the innermost frame (not any
5878 inline function call sites). */
5879 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5881 struct address_space
*aspace
=
5882 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5884 /* skip_inline_frames is expensive, so we avoid it if we can
5885 determine that the address is one where functions cannot have
5886 been inlined. This improves performance with inferiors that
5887 load a lot of shared libraries, because the solib event
5888 breakpoint is defined as the address of a function (i.e. not
5889 inline). Note that we have to check the previous PC as well
5890 as the current one to catch cases when we have just
5891 single-stepped off a breakpoint prior to reinstating it.
5892 Note that we're assuming that the code we single-step to is
5893 not inline, but that's not definitive: there's nothing
5894 preventing the event breakpoint function from containing
5895 inlined code, and the single-step ending up there. If the
5896 user had set a breakpoint on that inlined code, the missing
5897 skip_inline_frames call would break things. Fortunately
5898 that's an extremely unlikely scenario. */
5899 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5900 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5901 && ecs
->event_thread
->control
.trap_expected
5902 && pc_at_non_inline_function (aspace
,
5903 ecs
->event_thread
->prev_pc
,
5906 skip_inline_frames (ecs
->ptid
);
5908 /* Re-fetch current thread's frame in case that invalidated
5910 frame
= get_current_frame ();
5911 gdbarch
= get_frame_arch (frame
);
5915 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5916 && ecs
->event_thread
->control
.trap_expected
5917 && gdbarch_single_step_through_delay_p (gdbarch
)
5918 && currently_stepping (ecs
->event_thread
))
5920 /* We're trying to step off a breakpoint. Turns out that we're
5921 also on an instruction that needs to be stepped multiple
5922 times before it's been fully executing. E.g., architectures
5923 with a delay slot. It needs to be stepped twice, once for
5924 the instruction and once for the delay slot. */
5925 int step_through_delay
5926 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5928 if (debug_infrun
&& step_through_delay
)
5929 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5930 if (ecs
->event_thread
->control
.step_range_end
== 0
5931 && step_through_delay
)
5933 /* The user issued a continue when stopped at a breakpoint.
5934 Set up for another trap and get out of here. */
5935 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5939 else if (step_through_delay
)
5941 /* The user issued a step when stopped at a breakpoint.
5942 Maybe we should stop, maybe we should not - the delay
5943 slot *might* correspond to a line of source. In any
5944 case, don't decide that here, just set
5945 ecs->stepping_over_breakpoint, making sure we
5946 single-step again before breakpoints are re-inserted. */
5947 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5951 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5952 handles this event. */
5953 ecs
->event_thread
->control
.stop_bpstat
5954 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5955 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5957 /* Following in case break condition called a
5959 stop_print_frame
= 1;
5961 /* This is where we handle "moribund" watchpoints. Unlike
5962 software breakpoints traps, hardware watchpoint traps are
5963 always distinguishable from random traps. If no high-level
5964 watchpoint is associated with the reported stop data address
5965 anymore, then the bpstat does not explain the signal ---
5966 simply make sure to ignore it if `stopped_by_watchpoint' is
5970 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5971 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5973 && stopped_by_watchpoint
)
5974 fprintf_unfiltered (gdb_stdlog
,
5975 "infrun: no user watchpoint explains "
5976 "watchpoint SIGTRAP, ignoring\n");
5978 /* NOTE: cagney/2003-03-29: These checks for a random signal
5979 at one stage in the past included checks for an inferior
5980 function call's call dummy's return breakpoint. The original
5981 comment, that went with the test, read:
5983 ``End of a stack dummy. Some systems (e.g. Sony news) give
5984 another signal besides SIGTRAP, so check here as well as
5987 If someone ever tries to get call dummys on a
5988 non-executable stack to work (where the target would stop
5989 with something like a SIGSEGV), then those tests might need
5990 to be re-instated. Given, however, that the tests were only
5991 enabled when momentary breakpoints were not being used, I
5992 suspect that it won't be the case.
5994 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5995 be necessary for call dummies on a non-executable stack on
5998 /* See if the breakpoints module can explain the signal. */
6000 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6001 ecs
->event_thread
->suspend
.stop_signal
);
6003 /* Maybe this was a trap for a software breakpoint that has since
6005 if (random_signal
&& target_stopped_by_sw_breakpoint ())
6007 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
6009 struct regcache
*regcache
;
6012 /* Re-adjust PC to what the program would see if GDB was not
6014 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
6015 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6018 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
6020 if (record_full_is_used ())
6021 record_full_gdb_operation_disable_set ();
6023 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
6025 do_cleanups (old_cleanups
);
6030 /* A delayed software breakpoint event. Ignore the trap. */
6032 fprintf_unfiltered (gdb_stdlog
,
6033 "infrun: delayed software breakpoint "
6034 "trap, ignoring\n");
6039 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6040 has since been removed. */
6041 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6043 /* A delayed hardware breakpoint event. Ignore the trap. */
6045 fprintf_unfiltered (gdb_stdlog
,
6046 "infrun: delayed hardware breakpoint/watchpoint "
6047 "trap, ignoring\n");
6051 /* If not, perhaps stepping/nexting can. */
6053 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6054 && currently_stepping (ecs
->event_thread
));
6056 /* Perhaps the thread hit a single-step breakpoint of _another_
6057 thread. Single-step breakpoints are transparent to the
6058 breakpoints module. */
6060 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6062 /* No? Perhaps we got a moribund watchpoint. */
6064 random_signal
= !stopped_by_watchpoint
;
6066 /* Always stop if the user explicitly requested this thread to
6068 if (ecs
->event_thread
->stop_requested
)
6072 fprintf_unfiltered (gdb_stdlog
, "infrun: user-requested stop\n");
6075 /* For the program's own signals, act according to
6076 the signal handling tables. */
6080 /* Signal not for debugging purposes. */
6081 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
6082 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6085 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
6086 gdb_signal_to_symbol_string (stop_signal
));
6088 stopped_by_random_signal
= 1;
6090 /* Always stop on signals if we're either just gaining control
6091 of the program, or the user explicitly requested this thread
6092 to remain stopped. */
6093 if (stop_soon
!= NO_STOP_QUIETLY
6094 || ecs
->event_thread
->stop_requested
6096 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
6102 /* Notify observers the signal has "handle print" set. Note we
6103 returned early above if stopping; normal_stop handles the
6104 printing in that case. */
6105 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6107 /* The signal table tells us to print about this signal. */
6108 target_terminal_ours_for_output ();
6109 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
6110 target_terminal_inferior ();
6113 /* Clear the signal if it should not be passed. */
6114 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6115 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6117 if (ecs
->event_thread
->prev_pc
== stop_pc
6118 && ecs
->event_thread
->control
.trap_expected
6119 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6121 /* We were just starting a new sequence, attempting to
6122 single-step off of a breakpoint and expecting a SIGTRAP.
6123 Instead this signal arrives. This signal will take us out
6124 of the stepping range so GDB needs to remember to, when
6125 the signal handler returns, resume stepping off that
6127 /* To simplify things, "continue" is forced to use the same
6128 code paths as single-step - set a breakpoint at the
6129 signal return address and then, once hit, step off that
6132 fprintf_unfiltered (gdb_stdlog
,
6133 "infrun: signal arrived while stepping over "
6136 insert_hp_step_resume_breakpoint_at_frame (frame
);
6137 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6138 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6139 ecs
->event_thread
->control
.trap_expected
= 0;
6141 /* If we were nexting/stepping some other thread, switch to
6142 it, so that we don't continue it, losing control. */
6143 if (!switch_back_to_stepped_thread (ecs
))
6148 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6149 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6150 || ecs
->event_thread
->control
.step_range_end
== 1)
6151 && frame_id_eq (get_stack_frame_id (frame
),
6152 ecs
->event_thread
->control
.step_stack_frame_id
)
6153 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6155 /* The inferior is about to take a signal that will take it
6156 out of the single step range. Set a breakpoint at the
6157 current PC (which is presumably where the signal handler
6158 will eventually return) and then allow the inferior to
6161 Note that this is only needed for a signal delivered
6162 while in the single-step range. Nested signals aren't a
6163 problem as they eventually all return. */
6165 fprintf_unfiltered (gdb_stdlog
,
6166 "infrun: signal may take us out of "
6167 "single-step range\n");
6169 clear_step_over_info ();
6170 insert_hp_step_resume_breakpoint_at_frame (frame
);
6171 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6172 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6173 ecs
->event_thread
->control
.trap_expected
= 0;
6178 /* Note: step_resume_breakpoint may be non-NULL. This occures
6179 when either there's a nested signal, or when there's a
6180 pending signal enabled just as the signal handler returns
6181 (leaving the inferior at the step-resume-breakpoint without
6182 actually executing it). Either way continue until the
6183 breakpoint is really hit. */
6185 if (!switch_back_to_stepped_thread (ecs
))
6188 fprintf_unfiltered (gdb_stdlog
,
6189 "infrun: random signal, keep going\n");
6196 process_event_stop_test (ecs
);
6199 /* Come here when we've got some debug event / signal we can explain
6200 (IOW, not a random signal), and test whether it should cause a
6201 stop, or whether we should resume the inferior (transparently).
6202 E.g., could be a breakpoint whose condition evaluates false; we
6203 could be still stepping within the line; etc. */
6206 process_event_stop_test (struct execution_control_state
*ecs
)
6208 struct symtab_and_line stop_pc_sal
;
6209 struct frame_info
*frame
;
6210 struct gdbarch
*gdbarch
;
6211 CORE_ADDR jmp_buf_pc
;
6212 struct bpstat_what what
;
6214 /* Handle cases caused by hitting a breakpoint. */
6216 frame
= get_current_frame ();
6217 gdbarch
= get_frame_arch (frame
);
6219 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6221 if (what
.call_dummy
)
6223 stop_stack_dummy
= what
.call_dummy
;
6226 /* A few breakpoint types have callbacks associated (e.g.,
6227 bp_jit_event). Run them now. */
6228 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6230 /* If we hit an internal event that triggers symbol changes, the
6231 current frame will be invalidated within bpstat_what (e.g., if we
6232 hit an internal solib event). Re-fetch it. */
6233 frame
= get_current_frame ();
6234 gdbarch
= get_frame_arch (frame
);
6236 switch (what
.main_action
)
6238 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6239 /* If we hit the breakpoint at longjmp while stepping, we
6240 install a momentary breakpoint at the target of the
6244 fprintf_unfiltered (gdb_stdlog
,
6245 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6247 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6249 if (what
.is_longjmp
)
6251 struct value
*arg_value
;
6253 /* If we set the longjmp breakpoint via a SystemTap probe,
6254 then use it to extract the arguments. The destination PC
6255 is the third argument to the probe. */
6256 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6259 jmp_buf_pc
= value_as_address (arg_value
);
6260 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6262 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6263 || !gdbarch_get_longjmp_target (gdbarch
,
6264 frame
, &jmp_buf_pc
))
6267 fprintf_unfiltered (gdb_stdlog
,
6268 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6269 "(!gdbarch_get_longjmp_target)\n");
6274 /* Insert a breakpoint at resume address. */
6275 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6278 check_exception_resume (ecs
, frame
);
6282 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6284 struct frame_info
*init_frame
;
6286 /* There are several cases to consider.
6288 1. The initiating frame no longer exists. In this case we
6289 must stop, because the exception or longjmp has gone too
6292 2. The initiating frame exists, and is the same as the
6293 current frame. We stop, because the exception or longjmp
6296 3. The initiating frame exists and is different from the
6297 current frame. This means the exception or longjmp has
6298 been caught beneath the initiating frame, so keep going.
6300 4. longjmp breakpoint has been placed just to protect
6301 against stale dummy frames and user is not interested in
6302 stopping around longjmps. */
6305 fprintf_unfiltered (gdb_stdlog
,
6306 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6308 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6310 delete_exception_resume_breakpoint (ecs
->event_thread
);
6312 if (what
.is_longjmp
)
6314 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6316 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6324 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6328 struct frame_id current_id
6329 = get_frame_id (get_current_frame ());
6330 if (frame_id_eq (current_id
,
6331 ecs
->event_thread
->initiating_frame
))
6333 /* Case 2. Fall through. */
6343 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6345 delete_step_resume_breakpoint (ecs
->event_thread
);
6347 end_stepping_range (ecs
);
6351 case BPSTAT_WHAT_SINGLE
:
6353 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6354 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6355 /* Still need to check other stuff, at least the case where we
6356 are stepping and step out of the right range. */
6359 case BPSTAT_WHAT_STEP_RESUME
:
6361 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6363 delete_step_resume_breakpoint (ecs
->event_thread
);
6364 if (ecs
->event_thread
->control
.proceed_to_finish
6365 && execution_direction
== EXEC_REVERSE
)
6367 struct thread_info
*tp
= ecs
->event_thread
;
6369 /* We are finishing a function in reverse, and just hit the
6370 step-resume breakpoint at the start address of the
6371 function, and we're almost there -- just need to back up
6372 by one more single-step, which should take us back to the
6374 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6378 fill_in_stop_func (gdbarch
, ecs
);
6379 if (stop_pc
== ecs
->stop_func_start
6380 && execution_direction
== EXEC_REVERSE
)
6382 /* We are stepping over a function call in reverse, and just
6383 hit the step-resume breakpoint at the start address of
6384 the function. Go back to single-stepping, which should
6385 take us back to the function call. */
6386 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6392 case BPSTAT_WHAT_STOP_NOISY
:
6394 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6395 stop_print_frame
= 1;
6397 /* Assume the thread stopped for a breapoint. We'll still check
6398 whether a/the breakpoint is there when the thread is next
6400 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6405 case BPSTAT_WHAT_STOP_SILENT
:
6407 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6408 stop_print_frame
= 0;
6410 /* Assume the thread stopped for a breapoint. We'll still check
6411 whether a/the breakpoint is there when the thread is next
6413 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6417 case BPSTAT_WHAT_HP_STEP_RESUME
:
6419 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6421 delete_step_resume_breakpoint (ecs
->event_thread
);
6422 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6424 /* Back when the step-resume breakpoint was inserted, we
6425 were trying to single-step off a breakpoint. Go back to
6427 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6428 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6434 case BPSTAT_WHAT_KEEP_CHECKING
:
6438 /* If we stepped a permanent breakpoint and we had a high priority
6439 step-resume breakpoint for the address we stepped, but we didn't
6440 hit it, then we must have stepped into the signal handler. The
6441 step-resume was only necessary to catch the case of _not_
6442 stepping into the handler, so delete it, and fall through to
6443 checking whether the step finished. */
6444 if (ecs
->event_thread
->stepped_breakpoint
)
6446 struct breakpoint
*sr_bp
6447 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6450 && sr_bp
->loc
->permanent
6451 && sr_bp
->type
== bp_hp_step_resume
6452 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6455 fprintf_unfiltered (gdb_stdlog
,
6456 "infrun: stepped permanent breakpoint, stopped in "
6458 delete_step_resume_breakpoint (ecs
->event_thread
);
6459 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6463 /* We come here if we hit a breakpoint but should not stop for it.
6464 Possibly we also were stepping and should stop for that. So fall
6465 through and test for stepping. But, if not stepping, do not
6468 /* In all-stop mode, if we're currently stepping but have stopped in
6469 some other thread, we need to switch back to the stepped thread. */
6470 if (switch_back_to_stepped_thread (ecs
))
6473 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6476 fprintf_unfiltered (gdb_stdlog
,
6477 "infrun: step-resume breakpoint is inserted\n");
6479 /* Having a step-resume breakpoint overrides anything
6480 else having to do with stepping commands until
6481 that breakpoint is reached. */
6486 if (ecs
->event_thread
->control
.step_range_end
== 0)
6489 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6490 /* Likewise if we aren't even stepping. */
6495 /* Re-fetch current thread's frame in case the code above caused
6496 the frame cache to be re-initialized, making our FRAME variable
6497 a dangling pointer. */
6498 frame
= get_current_frame ();
6499 gdbarch
= get_frame_arch (frame
);
6500 fill_in_stop_func (gdbarch
, ecs
);
6502 /* If stepping through a line, keep going if still within it.
6504 Note that step_range_end is the address of the first instruction
6505 beyond the step range, and NOT the address of the last instruction
6508 Note also that during reverse execution, we may be stepping
6509 through a function epilogue and therefore must detect when
6510 the current-frame changes in the middle of a line. */
6512 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6513 && (execution_direction
!= EXEC_REVERSE
6514 || frame_id_eq (get_frame_id (frame
),
6515 ecs
->event_thread
->control
.step_frame_id
)))
6519 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6520 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6521 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6523 /* Tentatively re-enable range stepping; `resume' disables it if
6524 necessary (e.g., if we're stepping over a breakpoint or we
6525 have software watchpoints). */
6526 ecs
->event_thread
->control
.may_range_step
= 1;
6528 /* When stepping backward, stop at beginning of line range
6529 (unless it's the function entry point, in which case
6530 keep going back to the call point). */
6531 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6532 && stop_pc
!= ecs
->stop_func_start
6533 && execution_direction
== EXEC_REVERSE
)
6534 end_stepping_range (ecs
);
6541 /* We stepped out of the stepping range. */
6543 /* If we are stepping at the source level and entered the runtime
6544 loader dynamic symbol resolution code...
6546 EXEC_FORWARD: we keep on single stepping until we exit the run
6547 time loader code and reach the callee's address.
6549 EXEC_REVERSE: we've already executed the callee (backward), and
6550 the runtime loader code is handled just like any other
6551 undebuggable function call. Now we need only keep stepping
6552 backward through the trampoline code, and that's handled further
6553 down, so there is nothing for us to do here. */
6555 if (execution_direction
!= EXEC_REVERSE
6556 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6557 && in_solib_dynsym_resolve_code (stop_pc
))
6559 CORE_ADDR pc_after_resolver
=
6560 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6563 fprintf_unfiltered (gdb_stdlog
,
6564 "infrun: stepped into dynsym resolve code\n");
6566 if (pc_after_resolver
)
6568 /* Set up a step-resume breakpoint at the address
6569 indicated by SKIP_SOLIB_RESOLVER. */
6570 struct symtab_and_line sr_sal
;
6573 sr_sal
.pc
= pc_after_resolver
;
6574 sr_sal
.pspace
= get_frame_program_space (frame
);
6576 insert_step_resume_breakpoint_at_sal (gdbarch
,
6577 sr_sal
, null_frame_id
);
6584 if (ecs
->event_thread
->control
.step_range_end
!= 1
6585 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6586 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6587 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6590 fprintf_unfiltered (gdb_stdlog
,
6591 "infrun: stepped into signal trampoline\n");
6592 /* The inferior, while doing a "step" or "next", has ended up in
6593 a signal trampoline (either by a signal being delivered or by
6594 the signal handler returning). Just single-step until the
6595 inferior leaves the trampoline (either by calling the handler
6601 /* If we're in the return path from a shared library trampoline,
6602 we want to proceed through the trampoline when stepping. */
6603 /* macro/2012-04-25: This needs to come before the subroutine
6604 call check below as on some targets return trampolines look
6605 like subroutine calls (MIPS16 return thunks). */
6606 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6607 stop_pc
, ecs
->stop_func_name
)
6608 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6610 /* Determine where this trampoline returns. */
6611 CORE_ADDR real_stop_pc
;
6613 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6616 fprintf_unfiltered (gdb_stdlog
,
6617 "infrun: stepped into solib return tramp\n");
6619 /* Only proceed through if we know where it's going. */
6622 /* And put the step-breakpoint there and go until there. */
6623 struct symtab_and_line sr_sal
;
6625 init_sal (&sr_sal
); /* initialize to zeroes */
6626 sr_sal
.pc
= real_stop_pc
;
6627 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6628 sr_sal
.pspace
= get_frame_program_space (frame
);
6630 /* Do not specify what the fp should be when we stop since
6631 on some machines the prologue is where the new fp value
6633 insert_step_resume_breakpoint_at_sal (gdbarch
,
6634 sr_sal
, null_frame_id
);
6636 /* Restart without fiddling with the step ranges or
6643 /* Check for subroutine calls. The check for the current frame
6644 equalling the step ID is not necessary - the check of the
6645 previous frame's ID is sufficient - but it is a common case and
6646 cheaper than checking the previous frame's ID.
6648 NOTE: frame_id_eq will never report two invalid frame IDs as
6649 being equal, so to get into this block, both the current and
6650 previous frame must have valid frame IDs. */
6651 /* The outer_frame_id check is a heuristic to detect stepping
6652 through startup code. If we step over an instruction which
6653 sets the stack pointer from an invalid value to a valid value,
6654 we may detect that as a subroutine call from the mythical
6655 "outermost" function. This could be fixed by marking
6656 outermost frames as !stack_p,code_p,special_p. Then the
6657 initial outermost frame, before sp was valid, would
6658 have code_addr == &_start. See the comment in frame_id_eq
6660 if (!frame_id_eq (get_stack_frame_id (frame
),
6661 ecs
->event_thread
->control
.step_stack_frame_id
)
6662 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6663 ecs
->event_thread
->control
.step_stack_frame_id
)
6664 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6666 || (ecs
->event_thread
->control
.step_start_function
6667 != find_pc_function (stop_pc
)))))
6669 CORE_ADDR real_stop_pc
;
6672 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6674 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6676 /* I presume that step_over_calls is only 0 when we're
6677 supposed to be stepping at the assembly language level
6678 ("stepi"). Just stop. */
6679 /* And this works the same backward as frontward. MVS */
6680 end_stepping_range (ecs
);
6684 /* Reverse stepping through solib trampolines. */
6686 if (execution_direction
== EXEC_REVERSE
6687 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6688 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6689 || (ecs
->stop_func_start
== 0
6690 && in_solib_dynsym_resolve_code (stop_pc
))))
6692 /* Any solib trampoline code can be handled in reverse
6693 by simply continuing to single-step. We have already
6694 executed the solib function (backwards), and a few
6695 steps will take us back through the trampoline to the
6701 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6703 /* We're doing a "next".
6705 Normal (forward) execution: set a breakpoint at the
6706 callee's return address (the address at which the caller
6709 Reverse (backward) execution. set the step-resume
6710 breakpoint at the start of the function that we just
6711 stepped into (backwards), and continue to there. When we
6712 get there, we'll need to single-step back to the caller. */
6714 if (execution_direction
== EXEC_REVERSE
)
6716 /* If we're already at the start of the function, we've either
6717 just stepped backward into a single instruction function,
6718 or stepped back out of a signal handler to the first instruction
6719 of the function. Just keep going, which will single-step back
6721 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6723 struct symtab_and_line sr_sal
;
6725 /* Normal function call return (static or dynamic). */
6727 sr_sal
.pc
= ecs
->stop_func_start
;
6728 sr_sal
.pspace
= get_frame_program_space (frame
);
6729 insert_step_resume_breakpoint_at_sal (gdbarch
,
6730 sr_sal
, null_frame_id
);
6734 insert_step_resume_breakpoint_at_caller (frame
);
6740 /* If we are in a function call trampoline (a stub between the
6741 calling routine and the real function), locate the real
6742 function. That's what tells us (a) whether we want to step
6743 into it at all, and (b) what prologue we want to run to the
6744 end of, if we do step into it. */
6745 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6746 if (real_stop_pc
== 0)
6747 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6748 if (real_stop_pc
!= 0)
6749 ecs
->stop_func_start
= real_stop_pc
;
6751 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6753 struct symtab_and_line sr_sal
;
6756 sr_sal
.pc
= ecs
->stop_func_start
;
6757 sr_sal
.pspace
= get_frame_program_space (frame
);
6759 insert_step_resume_breakpoint_at_sal (gdbarch
,
6760 sr_sal
, null_frame_id
);
6765 /* If we have line number information for the function we are
6766 thinking of stepping into and the function isn't on the skip
6769 If there are several symtabs at that PC (e.g. with include
6770 files), just want to know whether *any* of them have line
6771 numbers. find_pc_line handles this. */
6773 struct symtab_and_line tmp_sal
;
6775 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6776 if (tmp_sal
.line
!= 0
6777 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6780 if (execution_direction
== EXEC_REVERSE
)
6781 handle_step_into_function_backward (gdbarch
, ecs
);
6783 handle_step_into_function (gdbarch
, ecs
);
6788 /* If we have no line number and the step-stop-if-no-debug is
6789 set, we stop the step so that the user has a chance to switch
6790 in assembly mode. */
6791 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6792 && step_stop_if_no_debug
)
6794 end_stepping_range (ecs
);
6798 if (execution_direction
== EXEC_REVERSE
)
6800 /* If we're already at the start of the function, we've either just
6801 stepped backward into a single instruction function without line
6802 number info, or stepped back out of a signal handler to the first
6803 instruction of the function without line number info. Just keep
6804 going, which will single-step back to the caller. */
6805 if (ecs
->stop_func_start
!= stop_pc
)
6807 /* Set a breakpoint at callee's start address.
6808 From there we can step once and be back in the caller. */
6809 struct symtab_and_line sr_sal
;
6812 sr_sal
.pc
= ecs
->stop_func_start
;
6813 sr_sal
.pspace
= get_frame_program_space (frame
);
6814 insert_step_resume_breakpoint_at_sal (gdbarch
,
6815 sr_sal
, null_frame_id
);
6819 /* Set a breakpoint at callee's return address (the address
6820 at which the caller will resume). */
6821 insert_step_resume_breakpoint_at_caller (frame
);
6827 /* Reverse stepping through solib trampolines. */
6829 if (execution_direction
== EXEC_REVERSE
6830 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6832 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6833 || (ecs
->stop_func_start
== 0
6834 && in_solib_dynsym_resolve_code (stop_pc
)))
6836 /* Any solib trampoline code can be handled in reverse
6837 by simply continuing to single-step. We have already
6838 executed the solib function (backwards), and a few
6839 steps will take us back through the trampoline to the
6844 else if (in_solib_dynsym_resolve_code (stop_pc
))
6846 /* Stepped backward into the solib dynsym resolver.
6847 Set a breakpoint at its start and continue, then
6848 one more step will take us out. */
6849 struct symtab_and_line sr_sal
;
6852 sr_sal
.pc
= ecs
->stop_func_start
;
6853 sr_sal
.pspace
= get_frame_program_space (frame
);
6854 insert_step_resume_breakpoint_at_sal (gdbarch
,
6855 sr_sal
, null_frame_id
);
6861 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6863 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6864 the trampoline processing logic, however, there are some trampolines
6865 that have no names, so we should do trampoline handling first. */
6866 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6867 && ecs
->stop_func_name
== NULL
6868 && stop_pc_sal
.line
== 0)
6871 fprintf_unfiltered (gdb_stdlog
,
6872 "infrun: stepped into undebuggable function\n");
6874 /* The inferior just stepped into, or returned to, an
6875 undebuggable function (where there is no debugging information
6876 and no line number corresponding to the address where the
6877 inferior stopped). Since we want to skip this kind of code,
6878 we keep going until the inferior returns from this
6879 function - unless the user has asked us not to (via
6880 set step-mode) or we no longer know how to get back
6881 to the call site. */
6882 if (step_stop_if_no_debug
6883 || !frame_id_p (frame_unwind_caller_id (frame
)))
6885 /* If we have no line number and the step-stop-if-no-debug
6886 is set, we stop the step so that the user has a chance to
6887 switch in assembly mode. */
6888 end_stepping_range (ecs
);
6893 /* Set a breakpoint at callee's return address (the address
6894 at which the caller will resume). */
6895 insert_step_resume_breakpoint_at_caller (frame
);
6901 if (ecs
->event_thread
->control
.step_range_end
== 1)
6903 /* It is stepi or nexti. We always want to stop stepping after
6906 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6907 end_stepping_range (ecs
);
6911 if (stop_pc_sal
.line
== 0)
6913 /* We have no line number information. That means to stop
6914 stepping (does this always happen right after one instruction,
6915 when we do "s" in a function with no line numbers,
6916 or can this happen as a result of a return or longjmp?). */
6918 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6919 end_stepping_range (ecs
);
6923 /* Look for "calls" to inlined functions, part one. If the inline
6924 frame machinery detected some skipped call sites, we have entered
6925 a new inline function. */
6927 if (frame_id_eq (get_frame_id (get_current_frame ()),
6928 ecs
->event_thread
->control
.step_frame_id
)
6929 && inline_skipped_frames (ecs
->ptid
))
6931 struct symtab_and_line call_sal
;
6934 fprintf_unfiltered (gdb_stdlog
,
6935 "infrun: stepped into inlined function\n");
6937 find_frame_sal (get_current_frame (), &call_sal
);
6939 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6941 /* For "step", we're going to stop. But if the call site
6942 for this inlined function is on the same source line as
6943 we were previously stepping, go down into the function
6944 first. Otherwise stop at the call site. */
6946 if (call_sal
.line
== ecs
->event_thread
->current_line
6947 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6948 step_into_inline_frame (ecs
->ptid
);
6950 end_stepping_range (ecs
);
6955 /* For "next", we should stop at the call site if it is on a
6956 different source line. Otherwise continue through the
6957 inlined function. */
6958 if (call_sal
.line
== ecs
->event_thread
->current_line
6959 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6962 end_stepping_range (ecs
);
6967 /* Look for "calls" to inlined functions, part two. If we are still
6968 in the same real function we were stepping through, but we have
6969 to go further up to find the exact frame ID, we are stepping
6970 through a more inlined call beyond its call site. */
6972 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6973 && !frame_id_eq (get_frame_id (get_current_frame ()),
6974 ecs
->event_thread
->control
.step_frame_id
)
6975 && stepped_in_from (get_current_frame (),
6976 ecs
->event_thread
->control
.step_frame_id
))
6979 fprintf_unfiltered (gdb_stdlog
,
6980 "infrun: stepping through inlined function\n");
6982 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6985 end_stepping_range (ecs
);
6989 if ((stop_pc
== stop_pc_sal
.pc
)
6990 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6991 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6993 /* We are at the start of a different line. So stop. Note that
6994 we don't stop if we step into the middle of a different line.
6995 That is said to make things like for (;;) statements work
6998 fprintf_unfiltered (gdb_stdlog
,
6999 "infrun: stepped to a different line\n");
7000 end_stepping_range (ecs
);
7004 /* We aren't done stepping.
7006 Optimize by setting the stepping range to the line.
7007 (We might not be in the original line, but if we entered a
7008 new line in mid-statement, we continue stepping. This makes
7009 things like for(;;) statements work better.) */
7011 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7012 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7013 ecs
->event_thread
->control
.may_range_step
= 1;
7014 set_step_info (frame
, stop_pc_sal
);
7017 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
7021 /* In all-stop mode, if we're currently stepping but have stopped in
7022 some other thread, we may need to switch back to the stepped
7023 thread. Returns true we set the inferior running, false if we left
7024 it stopped (and the event needs further processing). */
7027 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7029 if (!target_is_non_stop_p ())
7031 struct thread_info
*tp
;
7032 struct thread_info
*stepping_thread
;
7034 /* If any thread is blocked on some internal breakpoint, and we
7035 simply need to step over that breakpoint to get it going
7036 again, do that first. */
7038 /* However, if we see an event for the stepping thread, then we
7039 know all other threads have been moved past their breakpoints
7040 already. Let the caller check whether the step is finished,
7041 etc., before deciding to move it past a breakpoint. */
7042 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7045 /* Check if the current thread is blocked on an incomplete
7046 step-over, interrupted by a random signal. */
7047 if (ecs
->event_thread
->control
.trap_expected
7048 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7052 fprintf_unfiltered (gdb_stdlog
,
7053 "infrun: need to finish step-over of [%s]\n",
7054 target_pid_to_str (ecs
->event_thread
->ptid
));
7060 /* Check if the current thread is blocked by a single-step
7061 breakpoint of another thread. */
7062 if (ecs
->hit_singlestep_breakpoint
)
7066 fprintf_unfiltered (gdb_stdlog
,
7067 "infrun: need to step [%s] over single-step "
7069 target_pid_to_str (ecs
->ptid
));
7075 /* If this thread needs yet another step-over (e.g., stepping
7076 through a delay slot), do it first before moving on to
7078 if (thread_still_needs_step_over (ecs
->event_thread
))
7082 fprintf_unfiltered (gdb_stdlog
,
7083 "infrun: thread [%s] still needs step-over\n",
7084 target_pid_to_str (ecs
->event_thread
->ptid
));
7090 /* If scheduler locking applies even if not stepping, there's no
7091 need to walk over threads. Above we've checked whether the
7092 current thread is stepping. If some other thread not the
7093 event thread is stepping, then it must be that scheduler
7094 locking is not in effect. */
7095 if (schedlock_applies (ecs
->event_thread
))
7098 /* Otherwise, we no longer expect a trap in the current thread.
7099 Clear the trap_expected flag before switching back -- this is
7100 what keep_going does as well, if we call it. */
7101 ecs
->event_thread
->control
.trap_expected
= 0;
7103 /* Likewise, clear the signal if it should not be passed. */
7104 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7105 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7107 /* Do all pending step-overs before actually proceeding with
7109 if (start_step_over ())
7111 prepare_to_wait (ecs
);
7115 /* Look for the stepping/nexting thread. */
7116 stepping_thread
= NULL
;
7118 ALL_NON_EXITED_THREADS (tp
)
7120 /* Ignore threads of processes the caller is not
7123 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
7126 /* When stepping over a breakpoint, we lock all threads
7127 except the one that needs to move past the breakpoint.
7128 If a non-event thread has this set, the "incomplete
7129 step-over" check above should have caught it earlier. */
7130 if (tp
->control
.trap_expected
)
7132 internal_error (__FILE__
, __LINE__
,
7133 "[%s] has inconsistent state: "
7134 "trap_expected=%d\n",
7135 target_pid_to_str (tp
->ptid
),
7136 tp
->control
.trap_expected
);
7139 /* Did we find the stepping thread? */
7140 if (tp
->control
.step_range_end
)
7142 /* Yep. There should only one though. */
7143 gdb_assert (stepping_thread
== NULL
);
7145 /* The event thread is handled at the top, before we
7147 gdb_assert (tp
!= ecs
->event_thread
);
7149 /* If some thread other than the event thread is
7150 stepping, then scheduler locking can't be in effect,
7151 otherwise we wouldn't have resumed the current event
7152 thread in the first place. */
7153 gdb_assert (!schedlock_applies (tp
));
7155 stepping_thread
= tp
;
7159 if (stepping_thread
!= NULL
)
7162 fprintf_unfiltered (gdb_stdlog
,
7163 "infrun: switching back to stepped thread\n");
7165 if (keep_going_stepped_thread (stepping_thread
))
7167 prepare_to_wait (ecs
);
7176 /* Set a previously stepped thread back to stepping. Returns true on
7177 success, false if the resume is not possible (e.g., the thread
7181 keep_going_stepped_thread (struct thread_info
*tp
)
7183 struct frame_info
*frame
;
7184 struct execution_control_state ecss
;
7185 struct execution_control_state
*ecs
= &ecss
;
7187 /* If the stepping thread exited, then don't try to switch back and
7188 resume it, which could fail in several different ways depending
7189 on the target. Instead, just keep going.
7191 We can find a stepping dead thread in the thread list in two
7194 - The target supports thread exit events, and when the target
7195 tries to delete the thread from the thread list, inferior_ptid
7196 pointed at the exiting thread. In such case, calling
7197 delete_thread does not really remove the thread from the list;
7198 instead, the thread is left listed, with 'exited' state.
7200 - The target's debug interface does not support thread exit
7201 events, and so we have no idea whatsoever if the previously
7202 stepping thread is still alive. For that reason, we need to
7203 synchronously query the target now. */
7205 if (is_exited (tp
->ptid
)
7206 || !target_thread_alive (tp
->ptid
))
7209 fprintf_unfiltered (gdb_stdlog
,
7210 "infrun: not resuming previously "
7211 "stepped thread, it has vanished\n");
7213 delete_thread (tp
->ptid
);
7218 fprintf_unfiltered (gdb_stdlog
,
7219 "infrun: resuming previously stepped thread\n");
7221 reset_ecs (ecs
, tp
);
7222 switch_to_thread (tp
->ptid
);
7224 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7225 frame
= get_current_frame ();
7227 /* If the PC of the thread we were trying to single-step has
7228 changed, then that thread has trapped or been signaled, but the
7229 event has not been reported to GDB yet. Re-poll the target
7230 looking for this particular thread's event (i.e. temporarily
7231 enable schedlock) by:
7233 - setting a break at the current PC
7234 - resuming that particular thread, only (by setting trap
7237 This prevents us continuously moving the single-step breakpoint
7238 forward, one instruction at a time, overstepping. */
7240 if (stop_pc
!= tp
->prev_pc
)
7245 fprintf_unfiltered (gdb_stdlog
,
7246 "infrun: expected thread advanced also (%s -> %s)\n",
7247 paddress (target_gdbarch (), tp
->prev_pc
),
7248 paddress (target_gdbarch (), stop_pc
));
7250 /* Clear the info of the previous step-over, as it's no longer
7251 valid (if the thread was trying to step over a breakpoint, it
7252 has already succeeded). It's what keep_going would do too,
7253 if we called it. Do this before trying to insert the sss
7254 breakpoint, otherwise if we were previously trying to step
7255 over this exact address in another thread, the breakpoint is
7257 clear_step_over_info ();
7258 tp
->control
.trap_expected
= 0;
7260 insert_single_step_breakpoint (get_frame_arch (frame
),
7261 get_frame_address_space (frame
),
7265 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7266 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7271 fprintf_unfiltered (gdb_stdlog
,
7272 "infrun: expected thread still hasn't advanced\n");
7274 keep_going_pass_signal (ecs
);
7279 /* Is thread TP in the middle of (software or hardware)
7280 single-stepping? (Note the result of this function must never be
7281 passed directly as target_resume's STEP parameter.) */
7284 currently_stepping (struct thread_info
*tp
)
7286 return ((tp
->control
.step_range_end
7287 && tp
->control
.step_resume_breakpoint
== NULL
)
7288 || tp
->control
.trap_expected
7289 || tp
->stepped_breakpoint
7290 || bpstat_should_step ());
7293 /* Inferior has stepped into a subroutine call with source code that
7294 we should not step over. Do step to the first line of code in
7298 handle_step_into_function (struct gdbarch
*gdbarch
,
7299 struct execution_control_state
*ecs
)
7301 struct compunit_symtab
*cust
;
7302 struct symtab_and_line stop_func_sal
, sr_sal
;
7304 fill_in_stop_func (gdbarch
, ecs
);
7306 cust
= find_pc_compunit_symtab (stop_pc
);
7307 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7308 ecs
->stop_func_start
7309 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7311 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7312 /* Use the step_resume_break to step until the end of the prologue,
7313 even if that involves jumps (as it seems to on the vax under
7315 /* If the prologue ends in the middle of a source line, continue to
7316 the end of that source line (if it is still within the function).
7317 Otherwise, just go to end of prologue. */
7318 if (stop_func_sal
.end
7319 && stop_func_sal
.pc
!= ecs
->stop_func_start
7320 && stop_func_sal
.end
< ecs
->stop_func_end
)
7321 ecs
->stop_func_start
= stop_func_sal
.end
;
7323 /* Architectures which require breakpoint adjustment might not be able
7324 to place a breakpoint at the computed address. If so, the test
7325 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7326 ecs->stop_func_start to an address at which a breakpoint may be
7327 legitimately placed.
7329 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7330 made, GDB will enter an infinite loop when stepping through
7331 optimized code consisting of VLIW instructions which contain
7332 subinstructions corresponding to different source lines. On
7333 FR-V, it's not permitted to place a breakpoint on any but the
7334 first subinstruction of a VLIW instruction. When a breakpoint is
7335 set, GDB will adjust the breakpoint address to the beginning of
7336 the VLIW instruction. Thus, we need to make the corresponding
7337 adjustment here when computing the stop address. */
7339 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7341 ecs
->stop_func_start
7342 = gdbarch_adjust_breakpoint_address (gdbarch
,
7343 ecs
->stop_func_start
);
7346 if (ecs
->stop_func_start
== stop_pc
)
7348 /* We are already there: stop now. */
7349 end_stepping_range (ecs
);
7354 /* Put the step-breakpoint there and go until there. */
7355 init_sal (&sr_sal
); /* initialize to zeroes */
7356 sr_sal
.pc
= ecs
->stop_func_start
;
7357 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7358 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7360 /* Do not specify what the fp should be when we stop since on
7361 some machines the prologue is where the new fp value is
7363 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7365 /* And make sure stepping stops right away then. */
7366 ecs
->event_thread
->control
.step_range_end
7367 = ecs
->event_thread
->control
.step_range_start
;
7372 /* Inferior has stepped backward into a subroutine call with source
7373 code that we should not step over. Do step to the beginning of the
7374 last line of code in it. */
7377 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7378 struct execution_control_state
*ecs
)
7380 struct compunit_symtab
*cust
;
7381 struct symtab_and_line stop_func_sal
;
7383 fill_in_stop_func (gdbarch
, ecs
);
7385 cust
= find_pc_compunit_symtab (stop_pc
);
7386 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7387 ecs
->stop_func_start
7388 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7390 stop_func_sal
= find_pc_line (stop_pc
, 0);
7392 /* OK, we're just going to keep stepping here. */
7393 if (stop_func_sal
.pc
== stop_pc
)
7395 /* We're there already. Just stop stepping now. */
7396 end_stepping_range (ecs
);
7400 /* Else just reset the step range and keep going.
7401 No step-resume breakpoint, they don't work for
7402 epilogues, which can have multiple entry paths. */
7403 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7404 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7410 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7411 This is used to both functions and to skip over code. */
7414 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7415 struct symtab_and_line sr_sal
,
7416 struct frame_id sr_id
,
7417 enum bptype sr_type
)
7419 /* There should never be more than one step-resume or longjmp-resume
7420 breakpoint per thread, so we should never be setting a new
7421 step_resume_breakpoint when one is already active. */
7422 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7423 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7426 fprintf_unfiltered (gdb_stdlog
,
7427 "infrun: inserting step-resume breakpoint at %s\n",
7428 paddress (gdbarch
, sr_sal
.pc
));
7430 inferior_thread ()->control
.step_resume_breakpoint
7431 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7435 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7436 struct symtab_and_line sr_sal
,
7437 struct frame_id sr_id
)
7439 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7444 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7445 This is used to skip a potential signal handler.
7447 This is called with the interrupted function's frame. The signal
7448 handler, when it returns, will resume the interrupted function at
7452 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7454 struct symtab_and_line sr_sal
;
7455 struct gdbarch
*gdbarch
;
7457 gdb_assert (return_frame
!= NULL
);
7458 init_sal (&sr_sal
); /* initialize to zeros */
7460 gdbarch
= get_frame_arch (return_frame
);
7461 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7462 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7463 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7465 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7466 get_stack_frame_id (return_frame
),
7470 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7471 is used to skip a function after stepping into it (for "next" or if
7472 the called function has no debugging information).
7474 The current function has almost always been reached by single
7475 stepping a call or return instruction. NEXT_FRAME belongs to the
7476 current function, and the breakpoint will be set at the caller's
7479 This is a separate function rather than reusing
7480 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7481 get_prev_frame, which may stop prematurely (see the implementation
7482 of frame_unwind_caller_id for an example). */
7485 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7487 struct symtab_and_line sr_sal
;
7488 struct gdbarch
*gdbarch
;
7490 /* We shouldn't have gotten here if we don't know where the call site
7492 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7494 init_sal (&sr_sal
); /* initialize to zeros */
7496 gdbarch
= frame_unwind_caller_arch (next_frame
);
7497 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7498 frame_unwind_caller_pc (next_frame
));
7499 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7500 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7502 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7503 frame_unwind_caller_id (next_frame
));
7506 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7507 new breakpoint at the target of a jmp_buf. The handling of
7508 longjmp-resume uses the same mechanisms used for handling
7509 "step-resume" breakpoints. */
7512 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7514 /* There should never be more than one longjmp-resume breakpoint per
7515 thread, so we should never be setting a new
7516 longjmp_resume_breakpoint when one is already active. */
7517 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7520 fprintf_unfiltered (gdb_stdlog
,
7521 "infrun: inserting longjmp-resume breakpoint at %s\n",
7522 paddress (gdbarch
, pc
));
7524 inferior_thread ()->control
.exception_resume_breakpoint
=
7525 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7528 /* Insert an exception resume breakpoint. TP is the thread throwing
7529 the exception. The block B is the block of the unwinder debug hook
7530 function. FRAME is the frame corresponding to the call to this
7531 function. SYM is the symbol of the function argument holding the
7532 target PC of the exception. */
7535 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7536 const struct block
*b
,
7537 struct frame_info
*frame
,
7542 struct block_symbol vsym
;
7543 struct value
*value
;
7545 struct breakpoint
*bp
;
7547 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
7548 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7549 /* If the value was optimized out, revert to the old behavior. */
7550 if (! value_optimized_out (value
))
7552 handler
= value_as_address (value
);
7555 fprintf_unfiltered (gdb_stdlog
,
7556 "infrun: exception resume at %lx\n",
7557 (unsigned long) handler
);
7559 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7560 handler
, bp_exception_resume
);
7562 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7565 bp
->thread
= tp
->global_num
;
7566 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7569 CATCH (e
, RETURN_MASK_ERROR
)
7571 /* We want to ignore errors here. */
7576 /* A helper for check_exception_resume that sets an
7577 exception-breakpoint based on a SystemTap probe. */
7580 insert_exception_resume_from_probe (struct thread_info
*tp
,
7581 const struct bound_probe
*probe
,
7582 struct frame_info
*frame
)
7584 struct value
*arg_value
;
7586 struct breakpoint
*bp
;
7588 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7592 handler
= value_as_address (arg_value
);
7595 fprintf_unfiltered (gdb_stdlog
,
7596 "infrun: exception resume at %s\n",
7597 paddress (get_objfile_arch (probe
->objfile
),
7600 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7601 handler
, bp_exception_resume
);
7602 bp
->thread
= tp
->global_num
;
7603 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7606 /* This is called when an exception has been intercepted. Check to
7607 see whether the exception's destination is of interest, and if so,
7608 set an exception resume breakpoint there. */
7611 check_exception_resume (struct execution_control_state
*ecs
,
7612 struct frame_info
*frame
)
7614 struct bound_probe probe
;
7615 struct symbol
*func
;
7617 /* First see if this exception unwinding breakpoint was set via a
7618 SystemTap probe point. If so, the probe has two arguments: the
7619 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7620 set a breakpoint there. */
7621 probe
= find_probe_by_pc (get_frame_pc (frame
));
7624 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7628 func
= get_frame_function (frame
);
7634 const struct block
*b
;
7635 struct block_iterator iter
;
7639 /* The exception breakpoint is a thread-specific breakpoint on
7640 the unwinder's debug hook, declared as:
7642 void _Unwind_DebugHook (void *cfa, void *handler);
7644 The CFA argument indicates the frame to which control is
7645 about to be transferred. HANDLER is the destination PC.
7647 We ignore the CFA and set a temporary breakpoint at HANDLER.
7648 This is not extremely efficient but it avoids issues in gdb
7649 with computing the DWARF CFA, and it also works even in weird
7650 cases such as throwing an exception from inside a signal
7653 b
= SYMBOL_BLOCK_VALUE (func
);
7654 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7656 if (!SYMBOL_IS_ARGUMENT (sym
))
7663 insert_exception_resume_breakpoint (ecs
->event_thread
,
7669 CATCH (e
, RETURN_MASK_ERROR
)
7676 stop_waiting (struct execution_control_state
*ecs
)
7679 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7681 /* Let callers know we don't want to wait for the inferior anymore. */
7682 ecs
->wait_some_more
= 0;
7684 /* If all-stop, but the target is always in non-stop mode, stop all
7685 threads now that we're presenting the stop to the user. */
7686 if (!non_stop
&& target_is_non_stop_p ())
7687 stop_all_threads ();
7690 /* Like keep_going, but passes the signal to the inferior, even if the
7691 signal is set to nopass. */
7694 keep_going_pass_signal (struct execution_control_state
*ecs
)
7696 /* Make sure normal_stop is called if we get a QUIT handled before
7698 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
7700 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7701 gdb_assert (!ecs
->event_thread
->resumed
);
7703 /* Save the pc before execution, to compare with pc after stop. */
7704 ecs
->event_thread
->prev_pc
7705 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7707 if (ecs
->event_thread
->control
.trap_expected
)
7709 struct thread_info
*tp
= ecs
->event_thread
;
7712 fprintf_unfiltered (gdb_stdlog
,
7713 "infrun: %s has trap_expected set, "
7714 "resuming to collect trap\n",
7715 target_pid_to_str (tp
->ptid
));
7717 /* We haven't yet gotten our trap, and either: intercepted a
7718 non-signal event (e.g., a fork); or took a signal which we
7719 are supposed to pass through to the inferior. Simply
7721 discard_cleanups (old_cleanups
);
7722 resume (ecs
->event_thread
->suspend
.stop_signal
);
7724 else if (step_over_info_valid_p ())
7726 /* Another thread is stepping over a breakpoint in-line. If
7727 this thread needs a step-over too, queue the request. In
7728 either case, this resume must be deferred for later. */
7729 struct thread_info
*tp
= ecs
->event_thread
;
7731 if (ecs
->hit_singlestep_breakpoint
7732 || thread_still_needs_step_over (tp
))
7735 fprintf_unfiltered (gdb_stdlog
,
7736 "infrun: step-over already in progress: "
7737 "step-over for %s deferred\n",
7738 target_pid_to_str (tp
->ptid
));
7739 thread_step_over_chain_enqueue (tp
);
7744 fprintf_unfiltered (gdb_stdlog
,
7745 "infrun: step-over in progress: "
7746 "resume of %s deferred\n",
7747 target_pid_to_str (tp
->ptid
));
7750 discard_cleanups (old_cleanups
);
7754 struct regcache
*regcache
= get_current_regcache ();
7757 step_over_what step_what
;
7759 /* Either the trap was not expected, but we are continuing
7760 anyway (if we got a signal, the user asked it be passed to
7763 We got our expected trap, but decided we should resume from
7766 We're going to run this baby now!
7768 Note that insert_breakpoints won't try to re-insert
7769 already inserted breakpoints. Therefore, we don't
7770 care if breakpoints were already inserted, or not. */
7772 /* If we need to step over a breakpoint, and we're not using
7773 displaced stepping to do so, insert all breakpoints
7774 (watchpoints, etc.) but the one we're stepping over, step one
7775 instruction, and then re-insert the breakpoint when that step
7778 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7780 remove_bp
= (ecs
->hit_singlestep_breakpoint
7781 || (step_what
& STEP_OVER_BREAKPOINT
));
7782 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7784 /* We can't use displaced stepping if we need to step past a
7785 watchpoint. The instruction copied to the scratch pad would
7786 still trigger the watchpoint. */
7788 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7790 set_step_over_info (get_regcache_aspace (regcache
),
7791 regcache_read_pc (regcache
), remove_wps
,
7792 ecs
->event_thread
->global_num
);
7794 else if (remove_wps
)
7795 set_step_over_info (NULL
, 0, remove_wps
, -1);
7797 /* If we now need to do an in-line step-over, we need to stop
7798 all other threads. Note this must be done before
7799 insert_breakpoints below, because that removes the breakpoint
7800 we're about to step over, otherwise other threads could miss
7802 if (step_over_info_valid_p () && target_is_non_stop_p ())
7803 stop_all_threads ();
7805 /* Stop stepping if inserting breakpoints fails. */
7808 insert_breakpoints ();
7810 CATCH (e
, RETURN_MASK_ERROR
)
7812 exception_print (gdb_stderr
, e
);
7814 discard_cleanups (old_cleanups
);
7819 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7821 discard_cleanups (old_cleanups
);
7822 resume (ecs
->event_thread
->suspend
.stop_signal
);
7825 prepare_to_wait (ecs
);
7828 /* Called when we should continue running the inferior, because the
7829 current event doesn't cause a user visible stop. This does the
7830 resuming part; waiting for the next event is done elsewhere. */
7833 keep_going (struct execution_control_state
*ecs
)
7835 if (ecs
->event_thread
->control
.trap_expected
7836 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7837 ecs
->event_thread
->control
.trap_expected
= 0;
7839 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7840 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7841 keep_going_pass_signal (ecs
);
7844 /* This function normally comes after a resume, before
7845 handle_inferior_event exits. It takes care of any last bits of
7846 housekeeping, and sets the all-important wait_some_more flag. */
7849 prepare_to_wait (struct execution_control_state
*ecs
)
7852 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7854 ecs
->wait_some_more
= 1;
7856 if (!target_is_async_p ())
7857 mark_infrun_async_event_handler ();
7860 /* We are done with the step range of a step/next/si/ni command.
7861 Called once for each n of a "step n" operation. */
7864 end_stepping_range (struct execution_control_state
*ecs
)
7866 ecs
->event_thread
->control
.stop_step
= 1;
7870 /* Several print_*_reason functions to print why the inferior has stopped.
7871 We always print something when the inferior exits, or receives a signal.
7872 The rest of the cases are dealt with later on in normal_stop and
7873 print_it_typical. Ideally there should be a call to one of these
7874 print_*_reason functions functions from handle_inferior_event each time
7875 stop_waiting is called.
7877 Note that we don't call these directly, instead we delegate that to
7878 the interpreters, through observers. Interpreters then call these
7879 with whatever uiout is right. */
7882 print_end_stepping_range_reason (struct ui_out
*uiout
)
7884 /* For CLI-like interpreters, print nothing. */
7886 if (uiout
->is_mi_like_p ())
7888 uiout
->field_string ("reason",
7889 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7894 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7896 annotate_signalled ();
7897 if (uiout
->is_mi_like_p ())
7899 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7900 uiout
->text ("\nProgram terminated with signal ");
7901 annotate_signal_name ();
7902 uiout
->field_string ("signal-name",
7903 gdb_signal_to_name (siggnal
));
7904 annotate_signal_name_end ();
7906 annotate_signal_string ();
7907 uiout
->field_string ("signal-meaning",
7908 gdb_signal_to_string (siggnal
));
7909 annotate_signal_string_end ();
7910 uiout
->text (".\n");
7911 uiout
->text ("The program no longer exists.\n");
7915 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7917 struct inferior
*inf
= current_inferior ();
7918 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7920 annotate_exited (exitstatus
);
7923 if (uiout
->is_mi_like_p ())
7924 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
7925 uiout
->text ("[Inferior ");
7926 uiout
->text (plongest (inf
->num
));
7928 uiout
->text (pidstr
);
7929 uiout
->text (") exited with code ");
7930 uiout
->field_fmt ("exit-code", "0%o", (unsigned int) exitstatus
);
7931 uiout
->text ("]\n");
7935 if (uiout
->is_mi_like_p ())
7937 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7938 uiout
->text ("[Inferior ");
7939 uiout
->text (plongest (inf
->num
));
7941 uiout
->text (pidstr
);
7942 uiout
->text (") exited normally]\n");
7946 /* Some targets/architectures can do extra processing/display of
7947 segmentation faults. E.g., Intel MPX boundary faults.
7948 Call the architecture dependent function to handle the fault. */
7951 handle_segmentation_fault (struct ui_out
*uiout
)
7953 struct regcache
*regcache
= get_current_regcache ();
7954 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7956 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7957 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7961 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7963 struct thread_info
*thr
= inferior_thread ();
7967 if (uiout
->is_mi_like_p ())
7969 else if (show_thread_that_caused_stop ())
7973 uiout
->text ("\nThread ");
7974 uiout
->field_fmt ("thread-id", "%s", print_thread_id (thr
));
7976 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7979 uiout
->text (" \"");
7980 uiout
->field_fmt ("name", "%s", name
);
7985 uiout
->text ("\nProgram");
7987 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
7988 uiout
->text (" stopped");
7991 uiout
->text (" received signal ");
7992 annotate_signal_name ();
7993 if (uiout
->is_mi_like_p ())
7995 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
7996 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
7997 annotate_signal_name_end ();
7999 annotate_signal_string ();
8000 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
8002 if (siggnal
== GDB_SIGNAL_SEGV
)
8003 handle_segmentation_fault (uiout
);
8005 annotate_signal_string_end ();
8007 uiout
->text (".\n");
8011 print_no_history_reason (struct ui_out
*uiout
)
8013 uiout
->text ("\nNo more reverse-execution history.\n");
8016 /* Print current location without a level number, if we have changed
8017 functions or hit a breakpoint. Print source line if we have one.
8018 bpstat_print contains the logic deciding in detail what to print,
8019 based on the event(s) that just occurred. */
8022 print_stop_location (struct target_waitstatus
*ws
)
8025 enum print_what source_flag
;
8026 int do_frame_printing
= 1;
8027 struct thread_info
*tp
= inferior_thread ();
8029 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8033 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8034 should) carry around the function and does (or should) use
8035 that when doing a frame comparison. */
8036 if (tp
->control
.stop_step
8037 && frame_id_eq (tp
->control
.step_frame_id
,
8038 get_frame_id (get_current_frame ()))
8039 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
8041 /* Finished step, just print source line. */
8042 source_flag
= SRC_LINE
;
8046 /* Print location and source line. */
8047 source_flag
= SRC_AND_LOC
;
8050 case PRINT_SRC_AND_LOC
:
8051 /* Print location and source line. */
8052 source_flag
= SRC_AND_LOC
;
8054 case PRINT_SRC_ONLY
:
8055 source_flag
= SRC_LINE
;
8058 /* Something bogus. */
8059 source_flag
= SRC_LINE
;
8060 do_frame_printing
= 0;
8063 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8066 /* The behavior of this routine with respect to the source
8068 SRC_LINE: Print only source line
8069 LOCATION: Print only location
8070 SRC_AND_LOC: Print location and source line. */
8071 if (do_frame_printing
)
8072 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8078 print_stop_event (struct ui_out
*uiout
)
8080 struct target_waitstatus last
;
8082 struct thread_info
*tp
;
8084 get_last_target_status (&last_ptid
, &last
);
8087 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8089 print_stop_location (&last
);
8091 /* Display the auto-display expressions. */
8095 tp
= inferior_thread ();
8096 if (tp
->thread_fsm
!= NULL
8097 && thread_fsm_finished_p (tp
->thread_fsm
))
8099 struct return_value_info
*rv
;
8101 rv
= thread_fsm_return_value (tp
->thread_fsm
);
8103 print_return_value (uiout
, rv
);
8110 maybe_remove_breakpoints (void)
8112 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
8114 if (remove_breakpoints ())
8116 target_terminal_ours_for_output ();
8117 printf_filtered (_("Cannot remove breakpoints because "
8118 "program is no longer writable.\nFurther "
8119 "execution is probably impossible.\n"));
8124 /* The execution context that just caused a normal stop. */
8131 /* The event PTID. */
8135 /* If stopp for a thread event, this is the thread that caused the
8137 struct thread_info
*thread
;
8139 /* The inferior that caused the stop. */
8143 /* Returns a new stop context. If stopped for a thread event, this
8144 takes a strong reference to the thread. */
8146 static struct stop_context
*
8147 save_stop_context (void)
8149 struct stop_context
*sc
= XNEW (struct stop_context
);
8151 sc
->stop_id
= get_stop_id ();
8152 sc
->ptid
= inferior_ptid
;
8153 sc
->inf_num
= current_inferior ()->num
;
8155 if (!ptid_equal (inferior_ptid
, null_ptid
))
8157 /* Take a strong reference so that the thread can't be deleted
8159 sc
->thread
= inferior_thread ();
8160 sc
->thread
->incref ();
8168 /* Release a stop context previously created with save_stop_context.
8169 Releases the strong reference to the thread as well. */
8172 release_stop_context_cleanup (void *arg
)
8174 struct stop_context
*sc
= (struct stop_context
*) arg
;
8176 if (sc
->thread
!= NULL
)
8177 sc
->thread
->decref ();
8181 /* Return true if the current context no longer matches the saved stop
8185 stop_context_changed (struct stop_context
*prev
)
8187 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
8189 if (prev
->inf_num
!= current_inferior ()->num
)
8191 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
8193 if (get_stop_id () != prev
->stop_id
)
8203 struct target_waitstatus last
;
8205 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
8208 get_last_target_status (&last_ptid
, &last
);
8212 /* If an exception is thrown from this point on, make sure to
8213 propagate GDB's knowledge of the executing state to the
8214 frontend/user running state. A QUIT is an easy exception to see
8215 here, so do this before any filtered output. */
8217 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
8218 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8219 || last
.kind
== TARGET_WAITKIND_EXITED
)
8221 /* On some targets, we may still have live threads in the
8222 inferior when we get a process exit event. E.g., for
8223 "checkpoint", when the current checkpoint/fork exits,
8224 linux-fork.c automatically switches to another fork from
8225 within target_mourn_inferior. */
8226 if (!ptid_equal (inferior_ptid
, null_ptid
))
8228 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8229 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8232 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8233 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8235 /* As we're presenting a stop, and potentially removing breakpoints,
8236 update the thread list so we can tell whether there are threads
8237 running on the target. With target remote, for example, we can
8238 only learn about new threads when we explicitly update the thread
8239 list. Do this before notifying the interpreters about signal
8240 stops, end of stepping ranges, etc., so that the "new thread"
8241 output is emitted before e.g., "Program received signal FOO",
8242 instead of after. */
8243 update_thread_list ();
8245 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8246 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
8248 /* As with the notification of thread events, we want to delay
8249 notifying the user that we've switched thread context until
8250 the inferior actually stops.
8252 There's no point in saying anything if the inferior has exited.
8253 Note that SIGNALLED here means "exited with a signal", not
8254 "received a signal".
8256 Also skip saying anything in non-stop mode. In that mode, as we
8257 don't want GDB to switch threads behind the user's back, to avoid
8258 races where the user is typing a command to apply to thread x,
8259 but GDB switches to thread y before the user finishes entering
8260 the command, fetch_inferior_event installs a cleanup to restore
8261 the current thread back to the thread the user had selected right
8262 after this event is handled, so we're not really switching, only
8263 informing of a stop. */
8265 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8266 && target_has_execution
8267 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8268 && last
.kind
!= TARGET_WAITKIND_EXITED
8269 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8271 SWITCH_THRU_ALL_UIS ()
8273 target_terminal_ours_for_output ();
8274 printf_filtered (_("[Switching to %s]\n"),
8275 target_pid_to_str (inferior_ptid
));
8276 annotate_thread_changed ();
8278 previous_inferior_ptid
= inferior_ptid
;
8281 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8283 SWITCH_THRU_ALL_UIS ()
8284 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8286 target_terminal_ours_for_output ();
8287 printf_filtered (_("No unwaited-for children left.\n"));
8291 /* Note: this depends on the update_thread_list call above. */
8292 maybe_remove_breakpoints ();
8294 /* If an auto-display called a function and that got a signal,
8295 delete that auto-display to avoid an infinite recursion. */
8297 if (stopped_by_random_signal
)
8298 disable_current_display ();
8300 SWITCH_THRU_ALL_UIS ()
8302 async_enable_stdin ();
8305 /* Let the user/frontend see the threads as stopped. */
8306 do_cleanups (old_chain
);
8308 /* Select innermost stack frame - i.e., current frame is frame 0,
8309 and current location is based on that. Handle the case where the
8310 dummy call is returning after being stopped. E.g. the dummy call
8311 previously hit a breakpoint. (If the dummy call returns
8312 normally, we won't reach here.) Do this before the stop hook is
8313 run, so that it doesn't get to see the temporary dummy frame,
8314 which is not where we'll present the stop. */
8315 if (has_stack_frames ())
8317 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8319 /* Pop the empty frame that contains the stack dummy. This
8320 also restores inferior state prior to the call (struct
8321 infcall_suspend_state). */
8322 struct frame_info
*frame
= get_current_frame ();
8324 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8326 /* frame_pop calls reinit_frame_cache as the last thing it
8327 does which means there's now no selected frame. */
8330 select_frame (get_current_frame ());
8332 /* Set the current source location. */
8333 set_current_sal_from_frame (get_current_frame ());
8336 /* Look up the hook_stop and run it (CLI internally handles problem
8337 of stop_command's pre-hook not existing). */
8338 if (stop_command
!= NULL
)
8340 struct stop_context
*saved_context
= save_stop_context ();
8341 struct cleanup
*old_chain
8342 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8344 catch_errors (hook_stop_stub
, stop_command
,
8345 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
8347 /* If the stop hook resumes the target, then there's no point in
8348 trying to notify about the previous stop; its context is
8349 gone. Likewise if the command switches thread or inferior --
8350 the observers would print a stop for the wrong
8352 if (stop_context_changed (saved_context
))
8354 do_cleanups (old_chain
);
8357 do_cleanups (old_chain
);
8360 /* Notify observers about the stop. This is where the interpreters
8361 print the stop event. */
8362 if (!ptid_equal (inferior_ptid
, null_ptid
))
8363 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
8366 observer_notify_normal_stop (NULL
, stop_print_frame
);
8368 annotate_stopped ();
8370 if (target_has_execution
)
8372 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8373 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8374 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8375 Delete any breakpoint that is to be deleted at the next stop. */
8376 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8379 /* Try to get rid of automatically added inferiors that are no
8380 longer needed. Keeping those around slows down things linearly.
8381 Note that this never removes the current inferior. */
8388 hook_stop_stub (void *cmd
)
8390 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
8395 signal_stop_state (int signo
)
8397 return signal_stop
[signo
];
8401 signal_print_state (int signo
)
8403 return signal_print
[signo
];
8407 signal_pass_state (int signo
)
8409 return signal_program
[signo
];
8413 signal_cache_update (int signo
)
8417 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8418 signal_cache_update (signo
);
8423 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8424 && signal_print
[signo
] == 0
8425 && signal_program
[signo
] == 1
8426 && signal_catch
[signo
] == 0);
8430 signal_stop_update (int signo
, int state
)
8432 int ret
= signal_stop
[signo
];
8434 signal_stop
[signo
] = state
;
8435 signal_cache_update (signo
);
8440 signal_print_update (int signo
, int state
)
8442 int ret
= signal_print
[signo
];
8444 signal_print
[signo
] = state
;
8445 signal_cache_update (signo
);
8450 signal_pass_update (int signo
, int state
)
8452 int ret
= signal_program
[signo
];
8454 signal_program
[signo
] = state
;
8455 signal_cache_update (signo
);
8459 /* Update the global 'signal_catch' from INFO and notify the
8463 signal_catch_update (const unsigned int *info
)
8467 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8468 signal_catch
[i
] = info
[i
] > 0;
8469 signal_cache_update (-1);
8470 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8474 sig_print_header (void)
8476 printf_filtered (_("Signal Stop\tPrint\tPass "
8477 "to program\tDescription\n"));
8481 sig_print_info (enum gdb_signal oursig
)
8483 const char *name
= gdb_signal_to_name (oursig
);
8484 int name_padding
= 13 - strlen (name
);
8486 if (name_padding
<= 0)
8489 printf_filtered ("%s", name
);
8490 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8491 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8492 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8493 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8494 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8497 /* Specify how various signals in the inferior should be handled. */
8500 handle_command (char *args
, int from_tty
)
8502 int digits
, wordlen
;
8503 int sigfirst
, signum
, siglast
;
8504 enum gdb_signal oursig
;
8507 unsigned char *sigs
;
8511 error_no_arg (_("signal to handle"));
8514 /* Allocate and zero an array of flags for which signals to handle. */
8516 nsigs
= (int) GDB_SIGNAL_LAST
;
8517 sigs
= (unsigned char *) alloca (nsigs
);
8518 memset (sigs
, 0, nsigs
);
8520 /* Break the command line up into args. */
8522 gdb_argv
built_argv (args
);
8524 /* Walk through the args, looking for signal oursigs, signal names, and
8525 actions. Signal numbers and signal names may be interspersed with
8526 actions, with the actions being performed for all signals cumulatively
8527 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8529 for (char *arg
: built_argv
)
8531 wordlen
= strlen (arg
);
8532 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8536 sigfirst
= siglast
= -1;
8538 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8540 /* Apply action to all signals except those used by the
8541 debugger. Silently skip those. */
8544 siglast
= nsigs
- 1;
8546 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8548 SET_SIGS (nsigs
, sigs
, signal_stop
);
8549 SET_SIGS (nsigs
, sigs
, signal_print
);
8551 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8553 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8555 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8557 SET_SIGS (nsigs
, sigs
, signal_print
);
8559 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8561 SET_SIGS (nsigs
, sigs
, signal_program
);
8563 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8565 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8567 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8569 SET_SIGS (nsigs
, sigs
, signal_program
);
8571 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8573 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8574 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8576 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8578 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8580 else if (digits
> 0)
8582 /* It is numeric. The numeric signal refers to our own
8583 internal signal numbering from target.h, not to host/target
8584 signal number. This is a feature; users really should be
8585 using symbolic names anyway, and the common ones like
8586 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8588 sigfirst
= siglast
= (int)
8589 gdb_signal_from_command (atoi (arg
));
8590 if (arg
[digits
] == '-')
8593 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8595 if (sigfirst
> siglast
)
8597 /* Bet he didn't figure we'd think of this case... */
8605 oursig
= gdb_signal_from_name (arg
);
8606 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8608 sigfirst
= siglast
= (int) oursig
;
8612 /* Not a number and not a recognized flag word => complain. */
8613 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8617 /* If any signal numbers or symbol names were found, set flags for
8618 which signals to apply actions to. */
8620 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8622 switch ((enum gdb_signal
) signum
)
8624 case GDB_SIGNAL_TRAP
:
8625 case GDB_SIGNAL_INT
:
8626 if (!allsigs
&& !sigs
[signum
])
8628 if (query (_("%s is used by the debugger.\n\
8629 Are you sure you want to change it? "),
8630 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8636 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8637 gdb_flush (gdb_stdout
);
8642 case GDB_SIGNAL_DEFAULT
:
8643 case GDB_SIGNAL_UNKNOWN
:
8644 /* Make sure that "all" doesn't print these. */
8653 for (signum
= 0; signum
< nsigs
; signum
++)
8656 signal_cache_update (-1);
8657 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8658 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8662 /* Show the results. */
8663 sig_print_header ();
8664 for (; signum
< nsigs
; signum
++)
8666 sig_print_info ((enum gdb_signal
) signum
);
8673 /* Complete the "handle" command. */
8676 handle_completer (struct cmd_list_element
*ignore
,
8677 completion_tracker
&tracker
,
8678 const char *text
, const char *word
)
8680 static const char * const keywords
[] =
8694 signal_completer (ignore
, tracker
, text
, word
);
8695 complete_on_enum (tracker
, keywords
, word
, word
);
8699 gdb_signal_from_command (int num
)
8701 if (num
>= 1 && num
<= 15)
8702 return (enum gdb_signal
) num
;
8703 error (_("Only signals 1-15 are valid as numeric signals.\n\
8704 Use \"info signals\" for a list of symbolic signals."));
8707 /* Print current contents of the tables set by the handle command.
8708 It is possible we should just be printing signals actually used
8709 by the current target (but for things to work right when switching
8710 targets, all signals should be in the signal tables). */
8713 info_signals_command (char *signum_exp
, int from_tty
)
8715 enum gdb_signal oursig
;
8717 sig_print_header ();
8721 /* First see if this is a symbol name. */
8722 oursig
= gdb_signal_from_name (signum_exp
);
8723 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8725 /* No, try numeric. */
8727 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8729 sig_print_info (oursig
);
8733 printf_filtered ("\n");
8734 /* These ugly casts brought to you by the native VAX compiler. */
8735 for (oursig
= GDB_SIGNAL_FIRST
;
8736 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8737 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8741 if (oursig
!= GDB_SIGNAL_UNKNOWN
8742 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8743 sig_print_info (oursig
);
8746 printf_filtered (_("\nUse the \"handle\" command "
8747 "to change these tables.\n"));
8750 /* The $_siginfo convenience variable is a bit special. We don't know
8751 for sure the type of the value until we actually have a chance to
8752 fetch the data. The type can change depending on gdbarch, so it is
8753 also dependent on which thread you have selected.
8755 1. making $_siginfo be an internalvar that creates a new value on
8758 2. making the value of $_siginfo be an lval_computed value. */
8760 /* This function implements the lval_computed support for reading a
8764 siginfo_value_read (struct value
*v
)
8766 LONGEST transferred
;
8768 /* If we can access registers, so can we access $_siginfo. Likewise
8770 validate_registers_access ();
8773 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8775 value_contents_all_raw (v
),
8777 TYPE_LENGTH (value_type (v
)));
8779 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8780 error (_("Unable to read siginfo"));
8783 /* This function implements the lval_computed support for writing a
8787 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8789 LONGEST transferred
;
8791 /* If we can access registers, so can we access $_siginfo. Likewise
8793 validate_registers_access ();
8795 transferred
= target_write (¤t_target
,
8796 TARGET_OBJECT_SIGNAL_INFO
,
8798 value_contents_all_raw (fromval
),
8800 TYPE_LENGTH (value_type (fromval
)));
8802 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8803 error (_("Unable to write siginfo"));
8806 static const struct lval_funcs siginfo_value_funcs
=
8812 /* Return a new value with the correct type for the siginfo object of
8813 the current thread using architecture GDBARCH. Return a void value
8814 if there's no object available. */
8816 static struct value
*
8817 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8820 if (target_has_stack
8821 && !ptid_equal (inferior_ptid
, null_ptid
)
8822 && gdbarch_get_siginfo_type_p (gdbarch
))
8824 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8826 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8829 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8833 /* infcall_suspend_state contains state about the program itself like its
8834 registers and any signal it received when it last stopped.
8835 This state must be restored regardless of how the inferior function call
8836 ends (either successfully, or after it hits a breakpoint or signal)
8837 if the program is to properly continue where it left off. */
8839 struct infcall_suspend_state
8841 struct thread_suspend_state thread_suspend
;
8845 struct regcache
*registers
;
8847 /* Format of SIGINFO_DATA or NULL if it is not present. */
8848 struct gdbarch
*siginfo_gdbarch
;
8850 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8851 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8852 content would be invalid. */
8853 gdb_byte
*siginfo_data
;
8856 struct infcall_suspend_state
*
8857 save_infcall_suspend_state (void)
8859 struct infcall_suspend_state
*inf_state
;
8860 struct thread_info
*tp
= inferior_thread ();
8861 struct regcache
*regcache
= get_current_regcache ();
8862 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8863 gdb_byte
*siginfo_data
= NULL
;
8865 if (gdbarch_get_siginfo_type_p (gdbarch
))
8867 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8868 size_t len
= TYPE_LENGTH (type
);
8869 struct cleanup
*back_to
;
8871 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8872 back_to
= make_cleanup (xfree
, siginfo_data
);
8874 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8875 siginfo_data
, 0, len
) == len
)
8876 discard_cleanups (back_to
);
8879 /* Errors ignored. */
8880 do_cleanups (back_to
);
8881 siginfo_data
= NULL
;
8885 inf_state
= XCNEW (struct infcall_suspend_state
);
8889 inf_state
->siginfo_gdbarch
= gdbarch
;
8890 inf_state
->siginfo_data
= siginfo_data
;
8893 inf_state
->thread_suspend
= tp
->suspend
;
8895 /* run_inferior_call will not use the signal due to its `proceed' call with
8896 GDB_SIGNAL_0 anyway. */
8897 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8899 inf_state
->stop_pc
= stop_pc
;
8901 inf_state
->registers
= regcache_dup (regcache
);
8906 /* Restore inferior session state to INF_STATE. */
8909 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8911 struct thread_info
*tp
= inferior_thread ();
8912 struct regcache
*regcache
= get_current_regcache ();
8913 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8915 tp
->suspend
= inf_state
->thread_suspend
;
8917 stop_pc
= inf_state
->stop_pc
;
8919 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8921 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8923 /* Errors ignored. */
8924 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8925 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8928 /* The inferior can be gone if the user types "print exit(0)"
8929 (and perhaps other times). */
8930 if (target_has_execution
)
8931 /* NB: The register write goes through to the target. */
8932 regcache_cpy (regcache
, inf_state
->registers
);
8934 discard_infcall_suspend_state (inf_state
);
8938 do_restore_infcall_suspend_state_cleanup (void *state
)
8940 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
8944 make_cleanup_restore_infcall_suspend_state
8945 (struct infcall_suspend_state
*inf_state
)
8947 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8951 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8953 regcache_xfree (inf_state
->registers
);
8954 xfree (inf_state
->siginfo_data
);
8959 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8961 return inf_state
->registers
;
8964 /* infcall_control_state contains state regarding gdb's control of the
8965 inferior itself like stepping control. It also contains session state like
8966 the user's currently selected frame. */
8968 struct infcall_control_state
8970 struct thread_control_state thread_control
;
8971 struct inferior_control_state inferior_control
;
8974 enum stop_stack_kind stop_stack_dummy
;
8975 int stopped_by_random_signal
;
8977 /* ID if the selected frame when the inferior function call was made. */
8978 struct frame_id selected_frame_id
;
8981 /* Save all of the information associated with the inferior<==>gdb
8984 struct infcall_control_state
*
8985 save_infcall_control_state (void)
8987 struct infcall_control_state
*inf_status
=
8988 XNEW (struct infcall_control_state
);
8989 struct thread_info
*tp
= inferior_thread ();
8990 struct inferior
*inf
= current_inferior ();
8992 inf_status
->thread_control
= tp
->control
;
8993 inf_status
->inferior_control
= inf
->control
;
8995 tp
->control
.step_resume_breakpoint
= NULL
;
8996 tp
->control
.exception_resume_breakpoint
= NULL
;
8998 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8999 chain. If caller's caller is walking the chain, they'll be happier if we
9000 hand them back the original chain when restore_infcall_control_state is
9002 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9005 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9006 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9008 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
9014 restore_selected_frame (void *args
)
9016 struct frame_id
*fid
= (struct frame_id
*) args
;
9017 struct frame_info
*frame
;
9019 frame
= frame_find_by_id (*fid
);
9021 /* If inf_status->selected_frame_id is NULL, there was no previously
9025 warning (_("Unable to restore previously selected frame."));
9029 select_frame (frame
);
9034 /* Restore inferior session state to INF_STATUS. */
9037 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9039 struct thread_info
*tp
= inferior_thread ();
9040 struct inferior
*inf
= current_inferior ();
9042 if (tp
->control
.step_resume_breakpoint
)
9043 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9045 if (tp
->control
.exception_resume_breakpoint
)
9046 tp
->control
.exception_resume_breakpoint
->disposition
9047 = disp_del_at_next_stop
;
9049 /* Handle the bpstat_copy of the chain. */
9050 bpstat_clear (&tp
->control
.stop_bpstat
);
9052 tp
->control
= inf_status
->thread_control
;
9053 inf
->control
= inf_status
->inferior_control
;
9056 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9057 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9059 if (target_has_stack
)
9061 /* The point of catch_errors is that if the stack is clobbered,
9062 walking the stack might encounter a garbage pointer and
9063 error() trying to dereference it. */
9065 (restore_selected_frame
, &inf_status
->selected_frame_id
,
9066 "Unable to restore previously selected frame:\n",
9067 RETURN_MASK_ERROR
) == 0)
9068 /* Error in restoring the selected frame. Select the innermost
9070 select_frame (get_current_frame ());
9077 do_restore_infcall_control_state_cleanup (void *sts
)
9079 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
9083 make_cleanup_restore_infcall_control_state
9084 (struct infcall_control_state
*inf_status
)
9086 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
9090 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9092 if (inf_status
->thread_control
.step_resume_breakpoint
)
9093 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9094 = disp_del_at_next_stop
;
9096 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9097 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9098 = disp_del_at_next_stop
;
9100 /* See save_infcall_control_state for info on stop_bpstat. */
9101 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9109 clear_exit_convenience_vars (void)
9111 clear_internalvar (lookup_internalvar ("_exitsignal"));
9112 clear_internalvar (lookup_internalvar ("_exitcode"));
9116 /* User interface for reverse debugging:
9117 Set exec-direction / show exec-direction commands
9118 (returns error unless target implements to_set_exec_direction method). */
9120 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9121 static const char exec_forward
[] = "forward";
9122 static const char exec_reverse
[] = "reverse";
9123 static const char *exec_direction
= exec_forward
;
9124 static const char *const exec_direction_names
[] = {
9131 set_exec_direction_func (char *args
, int from_tty
,
9132 struct cmd_list_element
*cmd
)
9134 if (target_can_execute_reverse
)
9136 if (!strcmp (exec_direction
, exec_forward
))
9137 execution_direction
= EXEC_FORWARD
;
9138 else if (!strcmp (exec_direction
, exec_reverse
))
9139 execution_direction
= EXEC_REVERSE
;
9143 exec_direction
= exec_forward
;
9144 error (_("Target does not support this operation."));
9149 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9150 struct cmd_list_element
*cmd
, const char *value
)
9152 switch (execution_direction
) {
9154 fprintf_filtered (out
, _("Forward.\n"));
9157 fprintf_filtered (out
, _("Reverse.\n"));
9160 internal_error (__FILE__
, __LINE__
,
9161 _("bogus execution_direction value: %d"),
9162 (int) execution_direction
);
9167 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9168 struct cmd_list_element
*c
, const char *value
)
9170 fprintf_filtered (file
, _("Resuming the execution of threads "
9171 "of all processes is %s.\n"), value
);
9174 /* Implementation of `siginfo' variable. */
9176 static const struct internalvar_funcs siginfo_funcs
=
9183 /* Callback for infrun's target events source. This is marked when a
9184 thread has a pending status to process. */
9187 infrun_async_inferior_event_handler (gdb_client_data data
)
9189 inferior_event_handler (INF_REG_EVENT
, NULL
);
9193 _initialize_infrun (void)
9197 struct cmd_list_element
*c
;
9199 /* Register extra event sources in the event loop. */
9200 infrun_async_inferior_event_token
9201 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9203 add_info ("signals", info_signals_command
, _("\
9204 What debugger does when program gets various signals.\n\
9205 Specify a signal as argument to print info on that signal only."));
9206 add_info_alias ("handle", "signals", 0);
9208 c
= add_com ("handle", class_run
, handle_command
, _("\
9209 Specify how to handle signals.\n\
9210 Usage: handle SIGNAL [ACTIONS]\n\
9211 Args are signals and actions to apply to those signals.\n\
9212 If no actions are specified, the current settings for the specified signals\n\
9213 will be displayed instead.\n\
9215 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9216 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9217 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9218 The special arg \"all\" is recognized to mean all signals except those\n\
9219 used by the debugger, typically SIGTRAP and SIGINT.\n\
9221 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9222 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9223 Stop means reenter debugger if this signal happens (implies print).\n\
9224 Print means print a message if this signal happens.\n\
9225 Pass means let program see this signal; otherwise program doesn't know.\n\
9226 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9227 Pass and Stop may be combined.\n\
9229 Multiple signals may be specified. Signal numbers and signal names\n\
9230 may be interspersed with actions, with the actions being performed for\n\
9231 all signals cumulatively specified."));
9232 set_cmd_completer (c
, handle_completer
);
9235 stop_command
= add_cmd ("stop", class_obscure
,
9236 not_just_help_class_command
, _("\
9237 There is no `stop' command, but you can set a hook on `stop'.\n\
9238 This allows you to set a list of commands to be run each time execution\n\
9239 of the program stops."), &cmdlist
);
9241 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9242 Set inferior debugging."), _("\
9243 Show inferior debugging."), _("\
9244 When non-zero, inferior specific debugging is enabled."),
9247 &setdebuglist
, &showdebuglist
);
9249 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9250 &debug_displaced
, _("\
9251 Set displaced stepping debugging."), _("\
9252 Show displaced stepping debugging."), _("\
9253 When non-zero, displaced stepping specific debugging is enabled."),
9255 show_debug_displaced
,
9256 &setdebuglist
, &showdebuglist
);
9258 add_setshow_boolean_cmd ("non-stop", no_class
,
9260 Set whether gdb controls the inferior in non-stop mode."), _("\
9261 Show whether gdb controls the inferior in non-stop mode."), _("\
9262 When debugging a multi-threaded program and this setting is\n\
9263 off (the default, also called all-stop mode), when one thread stops\n\
9264 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9265 all other threads in the program while you interact with the thread of\n\
9266 interest. When you continue or step a thread, you can allow the other\n\
9267 threads to run, or have them remain stopped, but while you inspect any\n\
9268 thread's state, all threads stop.\n\
9270 In non-stop mode, when one thread stops, other threads can continue\n\
9271 to run freely. You'll be able to step each thread independently,\n\
9272 leave it stopped or free to run as needed."),
9278 numsigs
= (int) GDB_SIGNAL_LAST
;
9279 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9280 signal_print
= XNEWVEC (unsigned char, numsigs
);
9281 signal_program
= XNEWVEC (unsigned char, numsigs
);
9282 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9283 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9284 for (i
= 0; i
< numsigs
; i
++)
9287 signal_print
[i
] = 1;
9288 signal_program
[i
] = 1;
9289 signal_catch
[i
] = 0;
9292 /* Signals caused by debugger's own actions should not be given to
9293 the program afterwards.
9295 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9296 explicitly specifies that it should be delivered to the target
9297 program. Typically, that would occur when a user is debugging a
9298 target monitor on a simulator: the target monitor sets a
9299 breakpoint; the simulator encounters this breakpoint and halts
9300 the simulation handing control to GDB; GDB, noting that the stop
9301 address doesn't map to any known breakpoint, returns control back
9302 to the simulator; the simulator then delivers the hardware
9303 equivalent of a GDB_SIGNAL_TRAP to the program being
9305 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9306 signal_program
[GDB_SIGNAL_INT
] = 0;
9308 /* Signals that are not errors should not normally enter the debugger. */
9309 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9310 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9311 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9312 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9313 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9314 signal_print
[GDB_SIGNAL_PROF
] = 0;
9315 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9316 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9317 signal_stop
[GDB_SIGNAL_IO
] = 0;
9318 signal_print
[GDB_SIGNAL_IO
] = 0;
9319 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9320 signal_print
[GDB_SIGNAL_POLL
] = 0;
9321 signal_stop
[GDB_SIGNAL_URG
] = 0;
9322 signal_print
[GDB_SIGNAL_URG
] = 0;
9323 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9324 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9325 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9326 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9328 /* These signals are used internally by user-level thread
9329 implementations. (See signal(5) on Solaris.) Like the above
9330 signals, a healthy program receives and handles them as part of
9331 its normal operation. */
9332 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9333 signal_print
[GDB_SIGNAL_LWP
] = 0;
9334 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9335 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9336 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9337 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9338 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9339 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9341 /* Update cached state. */
9342 signal_cache_update (-1);
9344 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9345 &stop_on_solib_events
, _("\
9346 Set stopping for shared library events."), _("\
9347 Show stopping for shared library events."), _("\
9348 If nonzero, gdb will give control to the user when the dynamic linker\n\
9349 notifies gdb of shared library events. The most common event of interest\n\
9350 to the user would be loading/unloading of a new library."),
9351 set_stop_on_solib_events
,
9352 show_stop_on_solib_events
,
9353 &setlist
, &showlist
);
9355 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9356 follow_fork_mode_kind_names
,
9357 &follow_fork_mode_string
, _("\
9358 Set debugger response to a program call of fork or vfork."), _("\
9359 Show debugger response to a program call of fork or vfork."), _("\
9360 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9361 parent - the original process is debugged after a fork\n\
9362 child - the new process is debugged after a fork\n\
9363 The unfollowed process will continue to run.\n\
9364 By default, the debugger will follow the parent process."),
9366 show_follow_fork_mode_string
,
9367 &setlist
, &showlist
);
9369 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9370 follow_exec_mode_names
,
9371 &follow_exec_mode_string
, _("\
9372 Set debugger response to a program call of exec."), _("\
9373 Show debugger response to a program call of exec."), _("\
9374 An exec call replaces the program image of a process.\n\
9376 follow-exec-mode can be:\n\
9378 new - the debugger creates a new inferior and rebinds the process\n\
9379 to this new inferior. The program the process was running before\n\
9380 the exec call can be restarted afterwards by restarting the original\n\
9383 same - the debugger keeps the process bound to the same inferior.\n\
9384 The new executable image replaces the previous executable loaded in\n\
9385 the inferior. Restarting the inferior after the exec call restarts\n\
9386 the executable the process was running after the exec call.\n\
9388 By default, the debugger will use the same inferior."),
9390 show_follow_exec_mode_string
,
9391 &setlist
, &showlist
);
9393 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9394 scheduler_enums
, &scheduler_mode
, _("\
9395 Set mode for locking scheduler during execution."), _("\
9396 Show mode for locking scheduler during execution."), _("\
9397 off == no locking (threads may preempt at any time)\n\
9398 on == full locking (no thread except the current thread may run)\n\
9399 This applies to both normal execution and replay mode.\n\
9400 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9401 In this mode, other threads may run during other commands.\n\
9402 This applies to both normal execution and replay mode.\n\
9403 replay == scheduler locked in replay mode and unlocked during normal execution."),
9404 set_schedlock_func
, /* traps on target vector */
9405 show_scheduler_mode
,
9406 &setlist
, &showlist
);
9408 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9409 Set mode for resuming threads of all processes."), _("\
9410 Show mode for resuming threads of all processes."), _("\
9411 When on, execution commands (such as 'continue' or 'next') resume all\n\
9412 threads of all processes. When off (which is the default), execution\n\
9413 commands only resume the threads of the current process. The set of\n\
9414 threads that are resumed is further refined by the scheduler-locking\n\
9415 mode (see help set scheduler-locking)."),
9417 show_schedule_multiple
,
9418 &setlist
, &showlist
);
9420 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9421 Set mode of the step operation."), _("\
9422 Show mode of the step operation."), _("\
9423 When set, doing a step over a function without debug line information\n\
9424 will stop at the first instruction of that function. Otherwise, the\n\
9425 function is skipped and the step command stops at a different source line."),
9427 show_step_stop_if_no_debug
,
9428 &setlist
, &showlist
);
9430 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9431 &can_use_displaced_stepping
, _("\
9432 Set debugger's willingness to use displaced stepping."), _("\
9433 Show debugger's willingness to use displaced stepping."), _("\
9434 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9435 supported by the target architecture. If off, gdb will not use displaced\n\
9436 stepping to step over breakpoints, even if such is supported by the target\n\
9437 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9438 if the target architecture supports it and non-stop mode is active, but will not\n\
9439 use it in all-stop mode (see help set non-stop)."),
9441 show_can_use_displaced_stepping
,
9442 &setlist
, &showlist
);
9444 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9445 &exec_direction
, _("Set direction of execution.\n\
9446 Options are 'forward' or 'reverse'."),
9447 _("Show direction of execution (forward/reverse)."),
9448 _("Tells gdb whether to execute forward or backward."),
9449 set_exec_direction_func
, show_exec_direction_func
,
9450 &setlist
, &showlist
);
9452 /* Set/show detach-on-fork: user-settable mode. */
9454 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9455 Set whether gdb will detach the child of a fork."), _("\
9456 Show whether gdb will detach the child of a fork."), _("\
9457 Tells gdb whether to detach the child of a fork."),
9458 NULL
, NULL
, &setlist
, &showlist
);
9460 /* Set/show disable address space randomization mode. */
9462 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9463 &disable_randomization
, _("\
9464 Set disabling of debuggee's virtual address space randomization."), _("\
9465 Show disabling of debuggee's virtual address space randomization."), _("\
9466 When this mode is on (which is the default), randomization of the virtual\n\
9467 address space is disabled. Standalone programs run with the randomization\n\
9468 enabled by default on some platforms."),
9469 &set_disable_randomization
,
9470 &show_disable_randomization
,
9471 &setlist
, &showlist
);
9473 /* ptid initializations */
9474 inferior_ptid
= null_ptid
;
9475 target_last_wait_ptid
= minus_one_ptid
;
9477 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9478 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9479 observer_attach_thread_exit (infrun_thread_thread_exit
);
9480 observer_attach_inferior_exit (infrun_inferior_exit
);
9482 /* Explicitly create without lookup, since that tries to create a
9483 value with a void typed value, and when we get here, gdbarch
9484 isn't initialized yet. At this point, we're quite sure there
9485 isn't another convenience variable of the same name. */
9486 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9488 add_setshow_boolean_cmd ("observer", no_class
,
9489 &observer_mode_1
, _("\
9490 Set whether gdb controls the inferior in observer mode."), _("\
9491 Show whether gdb controls the inferior in observer mode."), _("\
9492 In observer mode, GDB can get data from the inferior, but not\n\
9493 affect its execution. Registers and memory may not be changed,\n\
9494 breakpoints may not be set, and the program cannot be interrupted\n\