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
);
1217 /* The old description may no longer be fit for the new image.
1218 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1219 old description; we'll read a new one below. No need to do
1220 this on "follow-exec-mode new", as the old inferior stays
1221 around (its description is later cleared/refetched on
1223 target_clear_description ();
1226 gdb_assert (current_program_space
== inf
->pspace
);
1228 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1229 because the proper displacement for a PIE (Position Independent
1230 Executable) main symbol file will only be computed by
1231 solib_create_inferior_hook below. breakpoint_re_set would fail
1232 to insert the breakpoints with the zero displacement. */
1233 try_open_exec_file (exec_file_host
, inf
, SYMFILE_DEFER_BP_RESET
);
1235 do_cleanups (old_chain
);
1237 /* If the target can specify a description, read it. Must do this
1238 after flipping to the new executable (because the target supplied
1239 description must be compatible with the executable's
1240 architecture, and the old executable may e.g., be 32-bit, while
1241 the new one 64-bit), and before anything involving memory or
1243 target_find_description ();
1245 /* The add_thread call ends up reading registers, so do it after updating the
1246 target description. */
1247 if (follow_exec_mode_string
== follow_exec_mode_new
)
1250 solib_create_inferior_hook (0);
1252 jit_inferior_created_hook ();
1254 breakpoint_re_set ();
1256 /* Reinsert all breakpoints. (Those which were symbolic have
1257 been reset to the proper address in the new a.out, thanks
1258 to symbol_file_command...). */
1259 insert_breakpoints ();
1261 /* The next resume of this inferior should bring it to the shlib
1262 startup breakpoints. (If the user had also set bp's on
1263 "main" from the old (parent) process, then they'll auto-
1264 matically get reset there in the new process.). */
1267 /* The queue of threads that need to do a step-over operation to get
1268 past e.g., a breakpoint. What technique is used to step over the
1269 breakpoint/watchpoint does not matter -- all threads end up in the
1270 same queue, to maintain rough temporal order of execution, in order
1271 to avoid starvation, otherwise, we could e.g., find ourselves
1272 constantly stepping the same couple threads past their breakpoints
1273 over and over, if the single-step finish fast enough. */
1274 struct thread_info
*step_over_queue_head
;
1276 /* Bit flags indicating what the thread needs to step over. */
1278 enum step_over_what_flag
1280 /* Step over a breakpoint. */
1281 STEP_OVER_BREAKPOINT
= 1,
1283 /* Step past a non-continuable watchpoint, in order to let the
1284 instruction execute so we can evaluate the watchpoint
1286 STEP_OVER_WATCHPOINT
= 2
1288 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1290 /* Info about an instruction that is being stepped over. */
1292 struct step_over_info
1294 /* If we're stepping past a breakpoint, this is the address space
1295 and address of the instruction the breakpoint is set at. We'll
1296 skip inserting all breakpoints here. Valid iff ASPACE is
1298 struct address_space
*aspace
;
1301 /* The instruction being stepped over triggers a nonsteppable
1302 watchpoint. If true, we'll skip inserting watchpoints. */
1303 int nonsteppable_watchpoint_p
;
1305 /* The thread's global number. */
1309 /* The step-over info of the location that is being stepped over.
1311 Note that with async/breakpoint always-inserted mode, a user might
1312 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1313 being stepped over. As setting a new breakpoint inserts all
1314 breakpoints, we need to make sure the breakpoint being stepped over
1315 isn't inserted then. We do that by only clearing the step-over
1316 info when the step-over is actually finished (or aborted).
1318 Presently GDB can only step over one breakpoint at any given time.
1319 Given threads that can't run code in the same address space as the
1320 breakpoint's can't really miss the breakpoint, GDB could be taught
1321 to step-over at most one breakpoint per address space (so this info
1322 could move to the address space object if/when GDB is extended).
1323 The set of breakpoints being stepped over will normally be much
1324 smaller than the set of all breakpoints, so a flag in the
1325 breakpoint location structure would be wasteful. A separate list
1326 also saves complexity and run-time, as otherwise we'd have to go
1327 through all breakpoint locations clearing their flag whenever we
1328 start a new sequence. Similar considerations weigh against storing
1329 this info in the thread object. Plus, not all step overs actually
1330 have breakpoint locations -- e.g., stepping past a single-step
1331 breakpoint, or stepping to complete a non-continuable
1333 static struct step_over_info step_over_info
;
1335 /* Record the address of the breakpoint/instruction we're currently
1337 N.B. We record the aspace and address now, instead of say just the thread,
1338 because when we need the info later the thread may be running. */
1341 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1342 int nonsteppable_watchpoint_p
,
1345 step_over_info
.aspace
= aspace
;
1346 step_over_info
.address
= address
;
1347 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1348 step_over_info
.thread
= thread
;
1351 /* Called when we're not longer stepping over a breakpoint / an
1352 instruction, so all breakpoints are free to be (re)inserted. */
1355 clear_step_over_info (void)
1358 fprintf_unfiltered (gdb_stdlog
,
1359 "infrun: clear_step_over_info\n");
1360 step_over_info
.aspace
= NULL
;
1361 step_over_info
.address
= 0;
1362 step_over_info
.nonsteppable_watchpoint_p
= 0;
1363 step_over_info
.thread
= -1;
1369 stepping_past_instruction_at (struct address_space
*aspace
,
1372 return (step_over_info
.aspace
!= NULL
1373 && breakpoint_address_match (aspace
, address
,
1374 step_over_info
.aspace
,
1375 step_over_info
.address
));
1381 thread_is_stepping_over_breakpoint (int thread
)
1383 return (step_over_info
.thread
!= -1
1384 && thread
== step_over_info
.thread
);
1390 stepping_past_nonsteppable_watchpoint (void)
1392 return step_over_info
.nonsteppable_watchpoint_p
;
1395 /* Returns true if step-over info is valid. */
1398 step_over_info_valid_p (void)
1400 return (step_over_info
.aspace
!= NULL
1401 || stepping_past_nonsteppable_watchpoint ());
1405 /* Displaced stepping. */
1407 /* In non-stop debugging mode, we must take special care to manage
1408 breakpoints properly; in particular, the traditional strategy for
1409 stepping a thread past a breakpoint it has hit is unsuitable.
1410 'Displaced stepping' is a tactic for stepping one thread past a
1411 breakpoint it has hit while ensuring that other threads running
1412 concurrently will hit the breakpoint as they should.
1414 The traditional way to step a thread T off a breakpoint in a
1415 multi-threaded program in all-stop mode is as follows:
1417 a0) Initially, all threads are stopped, and breakpoints are not
1419 a1) We single-step T, leaving breakpoints uninserted.
1420 a2) We insert breakpoints, and resume all threads.
1422 In non-stop debugging, however, this strategy is unsuitable: we
1423 don't want to have to stop all threads in the system in order to
1424 continue or step T past a breakpoint. Instead, we use displaced
1427 n0) Initially, T is stopped, other threads are running, and
1428 breakpoints are inserted.
1429 n1) We copy the instruction "under" the breakpoint to a separate
1430 location, outside the main code stream, making any adjustments
1431 to the instruction, register, and memory state as directed by
1433 n2) We single-step T over the instruction at its new location.
1434 n3) We adjust the resulting register and memory state as directed
1435 by T's architecture. This includes resetting T's PC to point
1436 back into the main instruction stream.
1439 This approach depends on the following gdbarch methods:
1441 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1442 indicate where to copy the instruction, and how much space must
1443 be reserved there. We use these in step n1.
1445 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1446 address, and makes any necessary adjustments to the instruction,
1447 register contents, and memory. We use this in step n1.
1449 - gdbarch_displaced_step_fixup adjusts registers and memory after
1450 we have successfuly single-stepped the instruction, to yield the
1451 same effect the instruction would have had if we had executed it
1452 at its original address. We use this in step n3.
1454 - gdbarch_displaced_step_free_closure provides cleanup.
1456 The gdbarch_displaced_step_copy_insn and
1457 gdbarch_displaced_step_fixup functions must be written so that
1458 copying an instruction with gdbarch_displaced_step_copy_insn,
1459 single-stepping across the copied instruction, and then applying
1460 gdbarch_displaced_insn_fixup should have the same effects on the
1461 thread's memory and registers as stepping the instruction in place
1462 would have. Exactly which responsibilities fall to the copy and
1463 which fall to the fixup is up to the author of those functions.
1465 See the comments in gdbarch.sh for details.
1467 Note that displaced stepping and software single-step cannot
1468 currently be used in combination, although with some care I think
1469 they could be made to. Software single-step works by placing
1470 breakpoints on all possible subsequent instructions; if the
1471 displaced instruction is a PC-relative jump, those breakpoints
1472 could fall in very strange places --- on pages that aren't
1473 executable, or at addresses that are not proper instruction
1474 boundaries. (We do generally let other threads run while we wait
1475 to hit the software single-step breakpoint, and they might
1476 encounter such a corrupted instruction.) One way to work around
1477 this would be to have gdbarch_displaced_step_copy_insn fully
1478 simulate the effect of PC-relative instructions (and return NULL)
1479 on architectures that use software single-stepping.
1481 In non-stop mode, we can have independent and simultaneous step
1482 requests, so more than one thread may need to simultaneously step
1483 over a breakpoint. The current implementation assumes there is
1484 only one scratch space per process. In this case, we have to
1485 serialize access to the scratch space. If thread A wants to step
1486 over a breakpoint, but we are currently waiting for some other
1487 thread to complete a displaced step, we leave thread A stopped and
1488 place it in the displaced_step_request_queue. Whenever a displaced
1489 step finishes, we pick the next thread in the queue and start a new
1490 displaced step operation on it. See displaced_step_prepare and
1491 displaced_step_fixup for details. */
1493 /* Per-inferior displaced stepping state. */
1494 struct displaced_step_inferior_state
1496 /* Pointer to next in linked list. */
1497 struct displaced_step_inferior_state
*next
;
1499 /* The process this displaced step state refers to. */
1502 /* True if preparing a displaced step ever failed. If so, we won't
1503 try displaced stepping for this inferior again. */
1506 /* If this is not null_ptid, this is the thread carrying out a
1507 displaced single-step in process PID. This thread's state will
1508 require fixing up once it has completed its step. */
1511 /* The architecture the thread had when we stepped it. */
1512 struct gdbarch
*step_gdbarch
;
1514 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1515 for post-step cleanup. */
1516 struct displaced_step_closure
*step_closure
;
1518 /* The address of the original instruction, and the copy we
1520 CORE_ADDR step_original
, step_copy
;
1522 /* Saved contents of copy area. */
1523 gdb_byte
*step_saved_copy
;
1526 /* The list of states of processes involved in displaced stepping
1528 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1530 /* Get the displaced stepping state of process PID. */
1532 static struct displaced_step_inferior_state
*
1533 get_displaced_stepping_state (int pid
)
1535 struct displaced_step_inferior_state
*state
;
1537 for (state
= displaced_step_inferior_states
;
1539 state
= state
->next
)
1540 if (state
->pid
== pid
)
1546 /* Returns true if any inferior has a thread doing a displaced
1550 displaced_step_in_progress_any_inferior (void)
1552 struct displaced_step_inferior_state
*state
;
1554 for (state
= displaced_step_inferior_states
;
1556 state
= state
->next
)
1557 if (!ptid_equal (state
->step_ptid
, null_ptid
))
1563 /* Return true if thread represented by PTID is doing a displaced
1567 displaced_step_in_progress_thread (ptid_t ptid
)
1569 struct displaced_step_inferior_state
*displaced
;
1571 gdb_assert (!ptid_equal (ptid
, null_ptid
));
1573 displaced
= get_displaced_stepping_state (ptid_get_pid (ptid
));
1575 return (displaced
!= NULL
&& ptid_equal (displaced
->step_ptid
, ptid
));
1578 /* Return true if process PID has a thread doing a displaced step. */
1581 displaced_step_in_progress (int pid
)
1583 struct displaced_step_inferior_state
*displaced
;
1585 displaced
= get_displaced_stepping_state (pid
);
1586 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1592 /* Add a new displaced stepping state for process PID to the displaced
1593 stepping state list, or return a pointer to an already existing
1594 entry, if it already exists. Never returns NULL. */
1596 static struct displaced_step_inferior_state
*
1597 add_displaced_stepping_state (int pid
)
1599 struct displaced_step_inferior_state
*state
;
1601 for (state
= displaced_step_inferior_states
;
1603 state
= state
->next
)
1604 if (state
->pid
== pid
)
1607 state
= XCNEW (struct displaced_step_inferior_state
);
1609 state
->next
= displaced_step_inferior_states
;
1610 displaced_step_inferior_states
= state
;
1615 /* If inferior is in displaced stepping, and ADDR equals to starting address
1616 of copy area, return corresponding displaced_step_closure. Otherwise,
1619 struct displaced_step_closure
*
1620 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1622 struct displaced_step_inferior_state
*displaced
1623 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1625 /* If checking the mode of displaced instruction in copy area. */
1626 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1627 && (displaced
->step_copy
== addr
))
1628 return displaced
->step_closure
;
1633 /* Remove the displaced stepping state of process PID. */
1636 remove_displaced_stepping_state (int pid
)
1638 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1640 gdb_assert (pid
!= 0);
1642 it
= displaced_step_inferior_states
;
1643 prev_next_p
= &displaced_step_inferior_states
;
1648 *prev_next_p
= it
->next
;
1653 prev_next_p
= &it
->next
;
1659 infrun_inferior_exit (struct inferior
*inf
)
1661 remove_displaced_stepping_state (inf
->pid
);
1664 /* If ON, and the architecture supports it, GDB will use displaced
1665 stepping to step over breakpoints. If OFF, or if the architecture
1666 doesn't support it, GDB will instead use the traditional
1667 hold-and-step approach. If AUTO (which is the default), GDB will
1668 decide which technique to use to step over breakpoints depending on
1669 which of all-stop or non-stop mode is active --- displaced stepping
1670 in non-stop mode; hold-and-step in all-stop mode. */
1672 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1675 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1676 struct cmd_list_element
*c
,
1679 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1680 fprintf_filtered (file
,
1681 _("Debugger's willingness to use displaced stepping "
1682 "to step over breakpoints is %s (currently %s).\n"),
1683 value
, target_is_non_stop_p () ? "on" : "off");
1685 fprintf_filtered (file
,
1686 _("Debugger's willingness to use displaced stepping "
1687 "to step over breakpoints is %s.\n"), value
);
1690 /* Return non-zero if displaced stepping can/should be used to step
1691 over breakpoints of thread TP. */
1694 use_displaced_stepping (struct thread_info
*tp
)
1696 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
1697 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1698 struct displaced_step_inferior_state
*displaced_state
;
1700 displaced_state
= get_displaced_stepping_state (ptid_get_pid (tp
->ptid
));
1702 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1703 && target_is_non_stop_p ())
1704 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1705 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1706 && find_record_target () == NULL
1707 && (displaced_state
== NULL
1708 || !displaced_state
->failed_before
));
1711 /* Clean out any stray displaced stepping state. */
1713 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1715 /* Indicate that there is no cleanup pending. */
1716 displaced
->step_ptid
= null_ptid
;
1718 xfree (displaced
->step_closure
);
1719 displaced
->step_closure
= NULL
;
1723 displaced_step_clear_cleanup (void *arg
)
1725 struct displaced_step_inferior_state
*state
1726 = (struct displaced_step_inferior_state
*) arg
;
1728 displaced_step_clear (state
);
1731 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1733 displaced_step_dump_bytes (struct ui_file
*file
,
1734 const gdb_byte
*buf
,
1739 for (i
= 0; i
< len
; i
++)
1740 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1741 fputs_unfiltered ("\n", file
);
1744 /* Prepare to single-step, using displaced stepping.
1746 Note that we cannot use displaced stepping when we have a signal to
1747 deliver. If we have a signal to deliver and an instruction to step
1748 over, then after the step, there will be no indication from the
1749 target whether the thread entered a signal handler or ignored the
1750 signal and stepped over the instruction successfully --- both cases
1751 result in a simple SIGTRAP. In the first case we mustn't do a
1752 fixup, and in the second case we must --- but we can't tell which.
1753 Comments in the code for 'random signals' in handle_inferior_event
1754 explain how we handle this case instead.
1756 Returns 1 if preparing was successful -- this thread is going to be
1757 stepped now; 0 if displaced stepping this thread got queued; or -1
1758 if this instruction can't be displaced stepped. */
1761 displaced_step_prepare_throw (ptid_t ptid
)
1763 struct cleanup
*ignore_cleanups
;
1764 struct thread_info
*tp
= find_thread_ptid (ptid
);
1765 struct regcache
*regcache
= get_thread_regcache (ptid
);
1766 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1767 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1768 CORE_ADDR original
, copy
;
1770 struct displaced_step_closure
*closure
;
1771 struct displaced_step_inferior_state
*displaced
;
1774 /* We should never reach this function if the architecture does not
1775 support displaced stepping. */
1776 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1778 /* Nor if the thread isn't meant to step over a breakpoint. */
1779 gdb_assert (tp
->control
.trap_expected
);
1781 /* Disable range stepping while executing in the scratch pad. We
1782 want a single-step even if executing the displaced instruction in
1783 the scratch buffer lands within the stepping range (e.g., a
1785 tp
->control
.may_range_step
= 0;
1787 /* We have to displaced step one thread at a time, as we only have
1788 access to a single scratch space per inferior. */
1790 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1792 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1794 /* Already waiting for a displaced step to finish. Defer this
1795 request and place in queue. */
1797 if (debug_displaced
)
1798 fprintf_unfiltered (gdb_stdlog
,
1799 "displaced: deferring step of %s\n",
1800 target_pid_to_str (ptid
));
1802 thread_step_over_chain_enqueue (tp
);
1807 if (debug_displaced
)
1808 fprintf_unfiltered (gdb_stdlog
,
1809 "displaced: stepping %s now\n",
1810 target_pid_to_str (ptid
));
1813 displaced_step_clear (displaced
);
1815 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
1816 inferior_ptid
= ptid
;
1818 original
= regcache_read_pc (regcache
);
1820 copy
= gdbarch_displaced_step_location (gdbarch
);
1821 len
= gdbarch_max_insn_length (gdbarch
);
1823 if (breakpoint_in_range_p (aspace
, copy
, len
))
1825 /* There's a breakpoint set in the scratch pad location range
1826 (which is usually around the entry point). We'd either
1827 install it before resuming, which would overwrite/corrupt the
1828 scratch pad, or if it was already inserted, this displaced
1829 step would overwrite it. The latter is OK in the sense that
1830 we already assume that no thread is going to execute the code
1831 in the scratch pad range (after initial startup) anyway, but
1832 the former is unacceptable. Simply punt and fallback to
1833 stepping over this breakpoint in-line. */
1834 if (debug_displaced
)
1836 fprintf_unfiltered (gdb_stdlog
,
1837 "displaced: breakpoint set in scratch pad. "
1838 "Stepping over breakpoint in-line instead.\n");
1844 /* Save the original contents of the copy area. */
1845 displaced
->step_saved_copy
= (gdb_byte
*) xmalloc (len
);
1846 ignore_cleanups
= make_cleanup (free_current_contents
,
1847 &displaced
->step_saved_copy
);
1848 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1850 throw_error (MEMORY_ERROR
,
1851 _("Error accessing memory address %s (%s) for "
1852 "displaced-stepping scratch space."),
1853 paddress (gdbarch
, copy
), safe_strerror (status
));
1854 if (debug_displaced
)
1856 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1857 paddress (gdbarch
, copy
));
1858 displaced_step_dump_bytes (gdb_stdlog
,
1859 displaced
->step_saved_copy
,
1863 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1864 original
, copy
, regcache
);
1865 if (closure
== NULL
)
1867 /* The architecture doesn't know how or want to displaced step
1868 this instruction or instruction sequence. Fallback to
1869 stepping over the breakpoint in-line. */
1870 do_cleanups (ignore_cleanups
);
1874 /* Save the information we need to fix things up if the step
1876 displaced
->step_ptid
= ptid
;
1877 displaced
->step_gdbarch
= gdbarch
;
1878 displaced
->step_closure
= closure
;
1879 displaced
->step_original
= original
;
1880 displaced
->step_copy
= copy
;
1882 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1884 /* Resume execution at the copy. */
1885 regcache_write_pc (regcache
, copy
);
1887 discard_cleanups (ignore_cleanups
);
1889 if (debug_displaced
)
1890 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1891 paddress (gdbarch
, copy
));
1896 /* Wrapper for displaced_step_prepare_throw that disabled further
1897 attempts at displaced stepping if we get a memory error. */
1900 displaced_step_prepare (ptid_t ptid
)
1906 prepared
= displaced_step_prepare_throw (ptid
);
1908 CATCH (ex
, RETURN_MASK_ERROR
)
1910 struct displaced_step_inferior_state
*displaced_state
;
1912 if (ex
.error
!= MEMORY_ERROR
1913 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1914 throw_exception (ex
);
1918 fprintf_unfiltered (gdb_stdlog
,
1919 "infrun: disabling displaced stepping: %s\n",
1923 /* Be verbose if "set displaced-stepping" is "on", silent if
1925 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1927 warning (_("disabling displaced stepping: %s"),
1931 /* Disable further displaced stepping attempts. */
1933 = get_displaced_stepping_state (ptid_get_pid (ptid
));
1934 displaced_state
->failed_before
= 1;
1942 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1943 const gdb_byte
*myaddr
, int len
)
1945 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
1947 inferior_ptid
= ptid
;
1948 write_memory (memaddr
, myaddr
, len
);
1951 /* Restore the contents of the copy area for thread PTID. */
1954 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1957 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1959 write_memory_ptid (ptid
, displaced
->step_copy
,
1960 displaced
->step_saved_copy
, len
);
1961 if (debug_displaced
)
1962 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1963 target_pid_to_str (ptid
),
1964 paddress (displaced
->step_gdbarch
,
1965 displaced
->step_copy
));
1968 /* If we displaced stepped an instruction successfully, adjust
1969 registers and memory to yield the same effect the instruction would
1970 have had if we had executed it at its original address, and return
1971 1. If the instruction didn't complete, relocate the PC and return
1972 -1. If the thread wasn't displaced stepping, return 0. */
1975 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1977 struct cleanup
*old_cleanups
;
1978 struct displaced_step_inferior_state
*displaced
1979 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1982 /* Was any thread of this process doing a displaced step? */
1983 if (displaced
== NULL
)
1986 /* Was this event for the pid we displaced? */
1987 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1988 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1991 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1993 displaced_step_restore (displaced
, displaced
->step_ptid
);
1995 /* Fixup may need to read memory/registers. Switch to the thread
1996 that we're fixing up. Also, target_stopped_by_watchpoint checks
1997 the current thread. */
1998 switch_to_thread (event_ptid
);
2000 /* Did the instruction complete successfully? */
2001 if (signal
== GDB_SIGNAL_TRAP
2002 && !(target_stopped_by_watchpoint ()
2003 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
2004 || target_have_steppable_watchpoint
)))
2006 /* Fix up the resulting state. */
2007 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
2008 displaced
->step_closure
,
2009 displaced
->step_original
,
2010 displaced
->step_copy
,
2011 get_thread_regcache (displaced
->step_ptid
));
2016 /* Since the instruction didn't complete, all we can do is
2018 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
2019 CORE_ADDR pc
= regcache_read_pc (regcache
);
2021 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
2022 regcache_write_pc (regcache
, pc
);
2026 do_cleanups (old_cleanups
);
2028 displaced
->step_ptid
= null_ptid
;
2033 /* Data to be passed around while handling an event. This data is
2034 discarded between events. */
2035 struct execution_control_state
2038 /* The thread that got the event, if this was a thread event; NULL
2040 struct thread_info
*event_thread
;
2042 struct target_waitstatus ws
;
2043 int stop_func_filled_in
;
2044 CORE_ADDR stop_func_start
;
2045 CORE_ADDR stop_func_end
;
2046 const char *stop_func_name
;
2049 /* True if the event thread hit the single-step breakpoint of
2050 another thread. Thus the event doesn't cause a stop, the thread
2051 needs to be single-stepped past the single-step breakpoint before
2052 we can switch back to the original stepping thread. */
2053 int hit_singlestep_breakpoint
;
2056 /* Clear ECS and set it to point at TP. */
2059 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
2061 memset (ecs
, 0, sizeof (*ecs
));
2062 ecs
->event_thread
= tp
;
2063 ecs
->ptid
= tp
->ptid
;
2066 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
2067 static void prepare_to_wait (struct execution_control_state
*ecs
);
2068 static int keep_going_stepped_thread (struct thread_info
*tp
);
2069 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
2071 /* Are there any pending step-over requests? If so, run all we can
2072 now and return true. Otherwise, return false. */
2075 start_step_over (void)
2077 struct thread_info
*tp
, *next
;
2079 /* Don't start a new step-over if we already have an in-line
2080 step-over operation ongoing. */
2081 if (step_over_info_valid_p ())
2084 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
2086 struct execution_control_state ecss
;
2087 struct execution_control_state
*ecs
= &ecss
;
2088 step_over_what step_what
;
2089 int must_be_in_line
;
2091 gdb_assert (!tp
->stop_requested
);
2093 next
= thread_step_over_chain_next (tp
);
2095 /* If this inferior already has a displaced step in process,
2096 don't start a new one. */
2097 if (displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2100 step_what
= thread_still_needs_step_over (tp
);
2101 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
2102 || ((step_what
& STEP_OVER_BREAKPOINT
)
2103 && !use_displaced_stepping (tp
)));
2105 /* We currently stop all threads of all processes to step-over
2106 in-line. If we need to start a new in-line step-over, let
2107 any pending displaced steps finish first. */
2108 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
2111 thread_step_over_chain_remove (tp
);
2113 if (step_over_queue_head
== NULL
)
2116 fprintf_unfiltered (gdb_stdlog
,
2117 "infrun: step-over queue now empty\n");
2120 if (tp
->control
.trap_expected
2124 internal_error (__FILE__
, __LINE__
,
2125 "[%s] has inconsistent state: "
2126 "trap_expected=%d, resumed=%d, executing=%d\n",
2127 target_pid_to_str (tp
->ptid
),
2128 tp
->control
.trap_expected
,
2134 fprintf_unfiltered (gdb_stdlog
,
2135 "infrun: resuming [%s] for step-over\n",
2136 target_pid_to_str (tp
->ptid
));
2138 /* keep_going_pass_signal skips the step-over if the breakpoint
2139 is no longer inserted. In all-stop, we want to keep looking
2140 for a thread that needs a step-over instead of resuming TP,
2141 because we wouldn't be able to resume anything else until the
2142 target stops again. In non-stop, the resume always resumes
2143 only TP, so it's OK to let the thread resume freely. */
2144 if (!target_is_non_stop_p () && !step_what
)
2147 switch_to_thread (tp
->ptid
);
2148 reset_ecs (ecs
, tp
);
2149 keep_going_pass_signal (ecs
);
2151 if (!ecs
->wait_some_more
)
2152 error (_("Command aborted."));
2154 gdb_assert (tp
->resumed
);
2156 /* If we started a new in-line step-over, we're done. */
2157 if (step_over_info_valid_p ())
2159 gdb_assert (tp
->control
.trap_expected
);
2163 if (!target_is_non_stop_p ())
2165 /* On all-stop, shouldn't have resumed unless we needed a
2167 gdb_assert (tp
->control
.trap_expected
2168 || tp
->step_after_step_resume_breakpoint
);
2170 /* With remote targets (at least), in all-stop, we can't
2171 issue any further remote commands until the program stops
2176 /* Either the thread no longer needed a step-over, or a new
2177 displaced stepping sequence started. Even in the latter
2178 case, continue looking. Maybe we can also start another
2179 displaced step on a thread of other process. */
2185 /* Update global variables holding ptids to hold NEW_PTID if they were
2186 holding OLD_PTID. */
2188 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2190 struct displaced_step_inferior_state
*displaced
;
2192 if (ptid_equal (inferior_ptid
, old_ptid
))
2193 inferior_ptid
= new_ptid
;
2195 for (displaced
= displaced_step_inferior_states
;
2197 displaced
= displaced
->next
)
2199 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
2200 displaced
->step_ptid
= new_ptid
;
2207 /* Things to clean up if we QUIT out of resume (). */
2209 resume_cleanups (void *ignore
)
2211 if (!ptid_equal (inferior_ptid
, null_ptid
))
2212 delete_single_step_breakpoints (inferior_thread ());
2217 static const char schedlock_off
[] = "off";
2218 static const char schedlock_on
[] = "on";
2219 static const char schedlock_step
[] = "step";
2220 static const char schedlock_replay
[] = "replay";
2221 static const char *const scheduler_enums
[] = {
2228 static const char *scheduler_mode
= schedlock_replay
;
2230 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2231 struct cmd_list_element
*c
, const char *value
)
2233 fprintf_filtered (file
,
2234 _("Mode for locking scheduler "
2235 "during execution is \"%s\".\n"),
2240 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
2242 if (!target_can_lock_scheduler
)
2244 scheduler_mode
= schedlock_off
;
2245 error (_("Target '%s' cannot support this command."), target_shortname
);
2249 /* True if execution commands resume all threads of all processes by
2250 default; otherwise, resume only threads of the current inferior
2252 int sched_multi
= 0;
2254 /* Try to setup for software single stepping over the specified location.
2255 Return 1 if target_resume() should use hardware single step.
2257 GDBARCH the current gdbarch.
2258 PC the location to step over. */
2261 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2265 if (execution_direction
== EXEC_FORWARD
2266 && gdbarch_software_single_step_p (gdbarch
))
2267 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2275 user_visible_resume_ptid (int step
)
2281 /* With non-stop mode on, threads are always handled
2283 resume_ptid
= inferior_ptid
;
2285 else if ((scheduler_mode
== schedlock_on
)
2286 || (scheduler_mode
== schedlock_step
&& step
))
2288 /* User-settable 'scheduler' mode requires solo thread
2290 resume_ptid
= inferior_ptid
;
2292 else if ((scheduler_mode
== schedlock_replay
)
2293 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2295 /* User-settable 'scheduler' mode requires solo thread resume in replay
2297 resume_ptid
= inferior_ptid
;
2299 else if (!sched_multi
&& target_supports_multi_process ())
2301 /* Resume all threads of the current process (and none of other
2303 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2307 /* Resume all threads of all processes. */
2308 resume_ptid
= RESUME_ALL
;
2314 /* Return a ptid representing the set of threads that we will resume,
2315 in the perspective of the target, assuming run control handling
2316 does not require leaving some threads stopped (e.g., stepping past
2317 breakpoint). USER_STEP indicates whether we're about to start the
2318 target for a stepping command. */
2321 internal_resume_ptid (int user_step
)
2323 /* In non-stop, we always control threads individually. Note that
2324 the target may always work in non-stop mode even with "set
2325 non-stop off", in which case user_visible_resume_ptid could
2326 return a wildcard ptid. */
2327 if (target_is_non_stop_p ())
2328 return inferior_ptid
;
2330 return user_visible_resume_ptid (user_step
);
2333 /* Wrapper for target_resume, that handles infrun-specific
2337 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2339 struct thread_info
*tp
= inferior_thread ();
2341 gdb_assert (!tp
->stop_requested
);
2343 /* Install inferior's terminal modes. */
2344 target_terminal_inferior ();
2346 /* Avoid confusing the next resume, if the next stop/resume
2347 happens to apply to another thread. */
2348 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2350 /* Advise target which signals may be handled silently.
2352 If we have removed breakpoints because we are stepping over one
2353 in-line (in any thread), we need to receive all signals to avoid
2354 accidentally skipping a breakpoint during execution of a signal
2357 Likewise if we're displaced stepping, otherwise a trap for a
2358 breakpoint in a signal handler might be confused with the
2359 displaced step finishing. We don't make the displaced_step_fixup
2360 step distinguish the cases instead, because:
2362 - a backtrace while stopped in the signal handler would show the
2363 scratch pad as frame older than the signal handler, instead of
2364 the real mainline code.
2366 - when the thread is later resumed, the signal handler would
2367 return to the scratch pad area, which would no longer be
2369 if (step_over_info_valid_p ()
2370 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2371 target_pass_signals (0, NULL
);
2373 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2375 target_resume (resume_ptid
, step
, sig
);
2377 target_commit_resume ();
2380 /* Resume the inferior, but allow a QUIT. This is useful if the user
2381 wants to interrupt some lengthy single-stepping operation
2382 (for child processes, the SIGINT goes to the inferior, and so
2383 we get a SIGINT random_signal, but for remote debugging and perhaps
2384 other targets, that's not true).
2386 SIG is the signal to give the inferior (zero for none). */
2388 resume (enum gdb_signal sig
)
2390 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2391 struct regcache
*regcache
= get_current_regcache ();
2392 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2393 struct thread_info
*tp
= inferior_thread ();
2394 CORE_ADDR pc
= regcache_read_pc (regcache
);
2395 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2397 /* This represents the user's step vs continue request. When
2398 deciding whether "set scheduler-locking step" applies, it's the
2399 user's intention that counts. */
2400 const int user_step
= tp
->control
.stepping_command
;
2401 /* This represents what we'll actually request the target to do.
2402 This can decay from a step to a continue, if e.g., we need to
2403 implement single-stepping with breakpoints (software
2407 gdb_assert (!tp
->stop_requested
);
2408 gdb_assert (!thread_is_in_step_over_chain (tp
));
2412 if (tp
->suspend
.waitstatus_pending_p
)
2417 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2419 fprintf_unfiltered (gdb_stdlog
,
2420 "infrun: resume: thread %s has pending wait "
2421 "status %s (currently_stepping=%d).\n",
2422 target_pid_to_str (tp
->ptid
), statstr
.c_str (),
2423 currently_stepping (tp
));
2428 /* FIXME: What should we do if we are supposed to resume this
2429 thread with a signal? Maybe we should maintain a queue of
2430 pending signals to deliver. */
2431 if (sig
!= GDB_SIGNAL_0
)
2433 warning (_("Couldn't deliver signal %s to %s."),
2434 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2437 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2438 discard_cleanups (old_cleanups
);
2440 if (target_can_async_p ())
2445 tp
->stepped_breakpoint
= 0;
2447 /* Depends on stepped_breakpoint. */
2448 step
= currently_stepping (tp
);
2450 if (current_inferior ()->waiting_for_vfork_done
)
2452 /* Don't try to single-step a vfork parent that is waiting for
2453 the child to get out of the shared memory region (by exec'ing
2454 or exiting). This is particularly important on software
2455 single-step archs, as the child process would trip on the
2456 software single step breakpoint inserted for the parent
2457 process. Since the parent will not actually execute any
2458 instruction until the child is out of the shared region (such
2459 are vfork's semantics), it is safe to simply continue it.
2460 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2461 the parent, and tell it to `keep_going', which automatically
2462 re-sets it stepping. */
2464 fprintf_unfiltered (gdb_stdlog
,
2465 "infrun: resume : clear step\n");
2470 fprintf_unfiltered (gdb_stdlog
,
2471 "infrun: resume (step=%d, signal=%s), "
2472 "trap_expected=%d, current thread [%s] at %s\n",
2473 step
, gdb_signal_to_symbol_string (sig
),
2474 tp
->control
.trap_expected
,
2475 target_pid_to_str (inferior_ptid
),
2476 paddress (gdbarch
, pc
));
2478 /* Normally, by the time we reach `resume', the breakpoints are either
2479 removed or inserted, as appropriate. The exception is if we're sitting
2480 at a permanent breakpoint; we need to step over it, but permanent
2481 breakpoints can't be removed. So we have to test for it here. */
2482 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2484 if (sig
!= GDB_SIGNAL_0
)
2486 /* We have a signal to pass to the inferior. The resume
2487 may, or may not take us to the signal handler. If this
2488 is a step, we'll need to stop in the signal handler, if
2489 there's one, (if the target supports stepping into
2490 handlers), or in the next mainline instruction, if
2491 there's no handler. If this is a continue, we need to be
2492 sure to run the handler with all breakpoints inserted.
2493 In all cases, set a breakpoint at the current address
2494 (where the handler returns to), and once that breakpoint
2495 is hit, resume skipping the permanent breakpoint. If
2496 that breakpoint isn't hit, then we've stepped into the
2497 signal handler (or hit some other event). We'll delete
2498 the step-resume breakpoint then. */
2501 fprintf_unfiltered (gdb_stdlog
,
2502 "infrun: resume: skipping permanent breakpoint, "
2503 "deliver signal first\n");
2505 clear_step_over_info ();
2506 tp
->control
.trap_expected
= 0;
2508 if (tp
->control
.step_resume_breakpoint
== NULL
)
2510 /* Set a "high-priority" step-resume, as we don't want
2511 user breakpoints at PC to trigger (again) when this
2513 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2514 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2516 tp
->step_after_step_resume_breakpoint
= step
;
2519 insert_breakpoints ();
2523 /* There's no signal to pass, we can go ahead and skip the
2524 permanent breakpoint manually. */
2526 fprintf_unfiltered (gdb_stdlog
,
2527 "infrun: resume: skipping permanent breakpoint\n");
2528 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2529 /* Update pc to reflect the new address from which we will
2530 execute instructions. */
2531 pc
= regcache_read_pc (regcache
);
2535 /* We've already advanced the PC, so the stepping part
2536 is done. Now we need to arrange for a trap to be
2537 reported to handle_inferior_event. Set a breakpoint
2538 at the current PC, and run to it. Don't update
2539 prev_pc, because if we end in
2540 switch_back_to_stepped_thread, we want the "expected
2541 thread advanced also" branch to be taken. IOW, we
2542 don't want this thread to step further from PC
2544 gdb_assert (!step_over_info_valid_p ());
2545 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2546 insert_breakpoints ();
2548 resume_ptid
= internal_resume_ptid (user_step
);
2549 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2550 discard_cleanups (old_cleanups
);
2557 /* If we have a breakpoint to step over, make sure to do a single
2558 step only. Same if we have software watchpoints. */
2559 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2560 tp
->control
.may_range_step
= 0;
2562 /* If enabled, step over breakpoints by executing a copy of the
2563 instruction at a different address.
2565 We can't use displaced stepping when we have a signal to deliver;
2566 the comments for displaced_step_prepare explain why. The
2567 comments in the handle_inferior event for dealing with 'random
2568 signals' explain what we do instead.
2570 We can't use displaced stepping when we are waiting for vfork_done
2571 event, displaced stepping breaks the vfork child similarly as single
2572 step software breakpoint. */
2573 if (tp
->control
.trap_expected
2574 && use_displaced_stepping (tp
)
2575 && !step_over_info_valid_p ()
2576 && sig
== GDB_SIGNAL_0
2577 && !current_inferior ()->waiting_for_vfork_done
)
2579 int prepared
= displaced_step_prepare (inferior_ptid
);
2584 fprintf_unfiltered (gdb_stdlog
,
2585 "Got placed in step-over queue\n");
2587 tp
->control
.trap_expected
= 0;
2588 discard_cleanups (old_cleanups
);
2591 else if (prepared
< 0)
2593 /* Fallback to stepping over the breakpoint in-line. */
2595 if (target_is_non_stop_p ())
2596 stop_all_threads ();
2598 set_step_over_info (get_regcache_aspace (regcache
),
2599 regcache_read_pc (regcache
), 0, tp
->global_num
);
2601 step
= maybe_software_singlestep (gdbarch
, pc
);
2603 insert_breakpoints ();
2605 else if (prepared
> 0)
2607 struct displaced_step_inferior_state
*displaced
;
2609 /* Update pc to reflect the new address from which we will
2610 execute instructions due to displaced stepping. */
2611 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2613 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2614 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2615 displaced
->step_closure
);
2619 /* Do we need to do it the hard way, w/temp breakpoints? */
2621 step
= maybe_software_singlestep (gdbarch
, pc
);
2623 /* Currently, our software single-step implementation leads to different
2624 results than hardware single-stepping in one situation: when stepping
2625 into delivering a signal which has an associated signal handler,
2626 hardware single-step will stop at the first instruction of the handler,
2627 while software single-step will simply skip execution of the handler.
2629 For now, this difference in behavior is accepted since there is no
2630 easy way to actually implement single-stepping into a signal handler
2631 without kernel support.
2633 However, there is one scenario where this difference leads to follow-on
2634 problems: if we're stepping off a breakpoint by removing all breakpoints
2635 and then single-stepping. In this case, the software single-step
2636 behavior means that even if there is a *breakpoint* in the signal
2637 handler, GDB still would not stop.
2639 Fortunately, we can at least fix this particular issue. We detect
2640 here the case where we are about to deliver a signal while software
2641 single-stepping with breakpoints removed. In this situation, we
2642 revert the decisions to remove all breakpoints and insert single-
2643 step breakpoints, and instead we install a step-resume breakpoint
2644 at the current address, deliver the signal without stepping, and
2645 once we arrive back at the step-resume breakpoint, actually step
2646 over the breakpoint we originally wanted to step over. */
2647 if (thread_has_single_step_breakpoints_set (tp
)
2648 && sig
!= GDB_SIGNAL_0
2649 && step_over_info_valid_p ())
2651 /* If we have nested signals or a pending signal is delivered
2652 immediately after a handler returns, might might already have
2653 a step-resume breakpoint set on the earlier handler. We cannot
2654 set another step-resume breakpoint; just continue on until the
2655 original breakpoint is hit. */
2656 if (tp
->control
.step_resume_breakpoint
== NULL
)
2658 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2659 tp
->step_after_step_resume_breakpoint
= 1;
2662 delete_single_step_breakpoints (tp
);
2664 clear_step_over_info ();
2665 tp
->control
.trap_expected
= 0;
2667 insert_breakpoints ();
2670 /* If STEP is set, it's a request to use hardware stepping
2671 facilities. But in that case, we should never
2672 use singlestep breakpoint. */
2673 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2675 /* Decide the set of threads to ask the target to resume. */
2676 if (tp
->control
.trap_expected
)
2678 /* We're allowing a thread to run past a breakpoint it has
2679 hit, either by single-stepping the thread with the breakpoint
2680 removed, or by displaced stepping, with the breakpoint inserted.
2681 In the former case, we need to single-step only this thread,
2682 and keep others stopped, as they can miss this breakpoint if
2683 allowed to run. That's not really a problem for displaced
2684 stepping, but, we still keep other threads stopped, in case
2685 another thread is also stopped for a breakpoint waiting for
2686 its turn in the displaced stepping queue. */
2687 resume_ptid
= inferior_ptid
;
2690 resume_ptid
= internal_resume_ptid (user_step
);
2692 if (execution_direction
!= EXEC_REVERSE
2693 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2695 /* There are two cases where we currently need to step a
2696 breakpoint instruction when we have a signal to deliver:
2698 - See handle_signal_stop where we handle random signals that
2699 could take out us out of the stepping range. Normally, in
2700 that case we end up continuing (instead of stepping) over the
2701 signal handler with a breakpoint at PC, but there are cases
2702 where we should _always_ single-step, even if we have a
2703 step-resume breakpoint, like when a software watchpoint is
2704 set. Assuming single-stepping and delivering a signal at the
2705 same time would takes us to the signal handler, then we could
2706 have removed the breakpoint at PC to step over it. However,
2707 some hardware step targets (like e.g., Mac OS) can't step
2708 into signal handlers, and for those, we need to leave the
2709 breakpoint at PC inserted, as otherwise if the handler
2710 recurses and executes PC again, it'll miss the breakpoint.
2711 So we leave the breakpoint inserted anyway, but we need to
2712 record that we tried to step a breakpoint instruction, so
2713 that adjust_pc_after_break doesn't end up confused.
2715 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2716 in one thread after another thread that was stepping had been
2717 momentarily paused for a step-over. When we re-resume the
2718 stepping thread, it may be resumed from that address with a
2719 breakpoint that hasn't trapped yet. Seen with
2720 gdb.threads/non-stop-fair-events.exp, on targets that don't
2721 do displaced stepping. */
2724 fprintf_unfiltered (gdb_stdlog
,
2725 "infrun: resume: [%s] stepped breakpoint\n",
2726 target_pid_to_str (tp
->ptid
));
2728 tp
->stepped_breakpoint
= 1;
2730 /* Most targets can step a breakpoint instruction, thus
2731 executing it normally. But if this one cannot, just
2732 continue and we will hit it anyway. */
2733 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2738 && tp
->control
.trap_expected
2739 && use_displaced_stepping (tp
)
2740 && !step_over_info_valid_p ())
2742 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2743 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2744 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2747 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2748 paddress (resume_gdbarch
, actual_pc
));
2749 read_memory (actual_pc
, buf
, sizeof (buf
));
2750 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2753 if (tp
->control
.may_range_step
)
2755 /* If we're resuming a thread with the PC out of the step
2756 range, then we're doing some nested/finer run control
2757 operation, like stepping the thread out of the dynamic
2758 linker or the displaced stepping scratch pad. We
2759 shouldn't have allowed a range step then. */
2760 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2763 do_target_resume (resume_ptid
, step
, sig
);
2765 discard_cleanups (old_cleanups
);
2772 /* Counter that tracks number of user visible stops. This can be used
2773 to tell whether a command has proceeded the inferior past the
2774 current location. This allows e.g., inferior function calls in
2775 breakpoint commands to not interrupt the command list. When the
2776 call finishes successfully, the inferior is standing at the same
2777 breakpoint as if nothing happened (and so we don't call
2779 static ULONGEST current_stop_id
;
2786 return current_stop_id
;
2789 /* Called when we report a user visible stop. */
2797 /* Clear out all variables saying what to do when inferior is continued.
2798 First do this, then set the ones you want, then call `proceed'. */
2801 clear_proceed_status_thread (struct thread_info
*tp
)
2804 fprintf_unfiltered (gdb_stdlog
,
2805 "infrun: clear_proceed_status_thread (%s)\n",
2806 target_pid_to_str (tp
->ptid
));
2808 /* If we're starting a new sequence, then the previous finished
2809 single-step is no longer relevant. */
2810 if (tp
->suspend
.waitstatus_pending_p
)
2812 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2815 fprintf_unfiltered (gdb_stdlog
,
2816 "infrun: clear_proceed_status: pending "
2817 "event of %s was a finished step. "
2819 target_pid_to_str (tp
->ptid
));
2821 tp
->suspend
.waitstatus_pending_p
= 0;
2822 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2824 else if (debug_infrun
)
2827 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2829 fprintf_unfiltered (gdb_stdlog
,
2830 "infrun: clear_proceed_status_thread: thread %s "
2831 "has pending wait status %s "
2832 "(currently_stepping=%d).\n",
2833 target_pid_to_str (tp
->ptid
), statstr
.c_str (),
2834 currently_stepping (tp
));
2838 /* If this signal should not be seen by program, give it zero.
2839 Used for debugging signals. */
2840 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2841 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2843 thread_fsm_delete (tp
->thread_fsm
);
2844 tp
->thread_fsm
= NULL
;
2846 tp
->control
.trap_expected
= 0;
2847 tp
->control
.step_range_start
= 0;
2848 tp
->control
.step_range_end
= 0;
2849 tp
->control
.may_range_step
= 0;
2850 tp
->control
.step_frame_id
= null_frame_id
;
2851 tp
->control
.step_stack_frame_id
= null_frame_id
;
2852 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2853 tp
->control
.step_start_function
= NULL
;
2854 tp
->stop_requested
= 0;
2856 tp
->control
.stop_step
= 0;
2858 tp
->control
.proceed_to_finish
= 0;
2860 tp
->control
.stepping_command
= 0;
2862 /* Discard any remaining commands or status from previous stop. */
2863 bpstat_clear (&tp
->control
.stop_bpstat
);
2867 clear_proceed_status (int step
)
2869 /* With scheduler-locking replay, stop replaying other threads if we're
2870 not replaying the user-visible resume ptid.
2872 This is a convenience feature to not require the user to explicitly
2873 stop replaying the other threads. We're assuming that the user's
2874 intent is to resume tracing the recorded process. */
2875 if (!non_stop
&& scheduler_mode
== schedlock_replay
2876 && target_record_is_replaying (minus_one_ptid
)
2877 && !target_record_will_replay (user_visible_resume_ptid (step
),
2878 execution_direction
))
2879 target_record_stop_replaying ();
2883 struct thread_info
*tp
;
2886 resume_ptid
= user_visible_resume_ptid (step
);
2888 /* In all-stop mode, delete the per-thread status of all threads
2889 we're about to resume, implicitly and explicitly. */
2890 ALL_NON_EXITED_THREADS (tp
)
2892 if (!ptid_match (tp
->ptid
, resume_ptid
))
2894 clear_proceed_status_thread (tp
);
2898 if (!ptid_equal (inferior_ptid
, null_ptid
))
2900 struct inferior
*inferior
;
2904 /* If in non-stop mode, only delete the per-thread status of
2905 the current thread. */
2906 clear_proceed_status_thread (inferior_thread ());
2909 inferior
= current_inferior ();
2910 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2913 observer_notify_about_to_proceed ();
2916 /* Returns true if TP is still stopped at a breakpoint that needs
2917 stepping-over in order to make progress. If the breakpoint is gone
2918 meanwhile, we can skip the whole step-over dance. */
2921 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2923 if (tp
->stepping_over_breakpoint
)
2925 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2927 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2928 regcache_read_pc (regcache
))
2929 == ordinary_breakpoint_here
)
2932 tp
->stepping_over_breakpoint
= 0;
2938 /* Check whether thread TP still needs to start a step-over in order
2939 to make progress when resumed. Returns an bitwise or of enum
2940 step_over_what bits, indicating what needs to be stepped over. */
2942 static step_over_what
2943 thread_still_needs_step_over (struct thread_info
*tp
)
2945 step_over_what what
= 0;
2947 if (thread_still_needs_step_over_bp (tp
))
2948 what
|= STEP_OVER_BREAKPOINT
;
2950 if (tp
->stepping_over_watchpoint
2951 && !target_have_steppable_watchpoint
)
2952 what
|= STEP_OVER_WATCHPOINT
;
2957 /* Returns true if scheduler locking applies. STEP indicates whether
2958 we're about to do a step/next-like command to a thread. */
2961 schedlock_applies (struct thread_info
*tp
)
2963 return (scheduler_mode
== schedlock_on
2964 || (scheduler_mode
== schedlock_step
2965 && tp
->control
.stepping_command
)
2966 || (scheduler_mode
== schedlock_replay
2967 && target_record_will_replay (minus_one_ptid
,
2968 execution_direction
)));
2971 /* Basic routine for continuing the program in various fashions.
2973 ADDR is the address to resume at, or -1 for resume where stopped.
2974 SIGGNAL is the signal to give it, or 0 for none,
2975 or -1 for act according to how it stopped.
2976 STEP is nonzero if should trap after one instruction.
2977 -1 means return after that and print nothing.
2978 You should probably set various step_... variables
2979 before calling here, if you are stepping.
2981 You should call clear_proceed_status before calling proceed. */
2984 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2986 struct regcache
*regcache
;
2987 struct gdbarch
*gdbarch
;
2988 struct thread_info
*tp
;
2990 struct address_space
*aspace
;
2992 struct execution_control_state ecss
;
2993 struct execution_control_state
*ecs
= &ecss
;
2994 struct cleanup
*old_chain
;
2995 struct cleanup
*defer_resume_cleanup
;
2998 /* If we're stopped at a fork/vfork, follow the branch set by the
2999 "set follow-fork-mode" command; otherwise, we'll just proceed
3000 resuming the current thread. */
3001 if (!follow_fork ())
3003 /* The target for some reason decided not to resume. */
3005 if (target_can_async_p ())
3006 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3010 /* We'll update this if & when we switch to a new thread. */
3011 previous_inferior_ptid
= inferior_ptid
;
3013 regcache
= get_current_regcache ();
3014 gdbarch
= get_regcache_arch (regcache
);
3015 aspace
= get_regcache_aspace (regcache
);
3016 pc
= regcache_read_pc (regcache
);
3017 tp
= inferior_thread ();
3019 /* Fill in with reasonable starting values. */
3020 init_thread_stepping_state (tp
);
3022 gdb_assert (!thread_is_in_step_over_chain (tp
));
3024 if (addr
== (CORE_ADDR
) -1)
3027 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3028 && execution_direction
!= EXEC_REVERSE
)
3029 /* There is a breakpoint at the address we will resume at,
3030 step one instruction before inserting breakpoints so that
3031 we do not stop right away (and report a second hit at this
3034 Note, we don't do this in reverse, because we won't
3035 actually be executing the breakpoint insn anyway.
3036 We'll be (un-)executing the previous instruction. */
3037 tp
->stepping_over_breakpoint
= 1;
3038 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3039 && gdbarch_single_step_through_delay (gdbarch
,
3040 get_current_frame ()))
3041 /* We stepped onto an instruction that needs to be stepped
3042 again before re-inserting the breakpoint, do so. */
3043 tp
->stepping_over_breakpoint
= 1;
3047 regcache_write_pc (regcache
, addr
);
3050 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3051 tp
->suspend
.stop_signal
= siggnal
;
3053 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3055 /* If an exception is thrown from this point on, make sure to
3056 propagate GDB's knowledge of the executing state to the
3057 frontend/user running state. */
3058 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3060 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3061 threads (e.g., we might need to set threads stepping over
3062 breakpoints first), from the user/frontend's point of view, all
3063 threads in RESUME_PTID are now running. Unless we're calling an
3064 inferior function, as in that case we pretend the inferior
3065 doesn't run at all. */
3066 if (!tp
->control
.in_infcall
)
3067 set_running (resume_ptid
, 1);
3070 fprintf_unfiltered (gdb_stdlog
,
3071 "infrun: proceed (addr=%s, signal=%s)\n",
3072 paddress (gdbarch
, addr
),
3073 gdb_signal_to_symbol_string (siggnal
));
3075 annotate_starting ();
3077 /* Make sure that output from GDB appears before output from the
3079 gdb_flush (gdb_stdout
);
3081 /* In a multi-threaded task we may select another thread and
3082 then continue or step.
3084 But if a thread that we're resuming had stopped at a breakpoint,
3085 it will immediately cause another breakpoint stop without any
3086 execution (i.e. it will report a breakpoint hit incorrectly). So
3087 we must step over it first.
3089 Look for threads other than the current (TP) that reported a
3090 breakpoint hit and haven't been resumed yet since. */
3092 /* If scheduler locking applies, we can avoid iterating over all
3094 if (!non_stop
&& !schedlock_applies (tp
))
3096 struct thread_info
*current
= tp
;
3098 ALL_NON_EXITED_THREADS (tp
)
3100 /* Ignore the current thread here. It's handled
3105 /* Ignore threads of processes we're not resuming. */
3106 if (!ptid_match (tp
->ptid
, resume_ptid
))
3109 if (!thread_still_needs_step_over (tp
))
3112 gdb_assert (!thread_is_in_step_over_chain (tp
));
3115 fprintf_unfiltered (gdb_stdlog
,
3116 "infrun: need to step-over [%s] first\n",
3117 target_pid_to_str (tp
->ptid
));
3119 thread_step_over_chain_enqueue (tp
);
3125 /* Enqueue the current thread last, so that we move all other
3126 threads over their breakpoints first. */
3127 if (tp
->stepping_over_breakpoint
)
3128 thread_step_over_chain_enqueue (tp
);
3130 /* If the thread isn't started, we'll still need to set its prev_pc,
3131 so that switch_back_to_stepped_thread knows the thread hasn't
3132 advanced. Must do this before resuming any thread, as in
3133 all-stop/remote, once we resume we can't send any other packet
3134 until the target stops again. */
3135 tp
->prev_pc
= regcache_read_pc (regcache
);
3137 defer_resume_cleanup
= make_cleanup_defer_target_commit_resume ();
3139 started
= start_step_over ();
3141 if (step_over_info_valid_p ())
3143 /* Either this thread started a new in-line step over, or some
3144 other thread was already doing one. In either case, don't
3145 resume anything else until the step-over is finished. */
3147 else if (started
&& !target_is_non_stop_p ())
3149 /* A new displaced stepping sequence was started. In all-stop,
3150 we can't talk to the target anymore until it next stops. */
3152 else if (!non_stop
&& target_is_non_stop_p ())
3154 /* In all-stop, but the target is always in non-stop mode.
3155 Start all other threads that are implicitly resumed too. */
3156 ALL_NON_EXITED_THREADS (tp
)
3158 /* Ignore threads of processes we're not resuming. */
3159 if (!ptid_match (tp
->ptid
, resume_ptid
))
3165 fprintf_unfiltered (gdb_stdlog
,
3166 "infrun: proceed: [%s] resumed\n",
3167 target_pid_to_str (tp
->ptid
));
3168 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3172 if (thread_is_in_step_over_chain (tp
))
3175 fprintf_unfiltered (gdb_stdlog
,
3176 "infrun: proceed: [%s] needs step-over\n",
3177 target_pid_to_str (tp
->ptid
));
3182 fprintf_unfiltered (gdb_stdlog
,
3183 "infrun: proceed: resuming %s\n",
3184 target_pid_to_str (tp
->ptid
));
3186 reset_ecs (ecs
, tp
);
3187 switch_to_thread (tp
->ptid
);
3188 keep_going_pass_signal (ecs
);
3189 if (!ecs
->wait_some_more
)
3190 error (_("Command aborted."));
3193 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3195 /* The thread wasn't started, and isn't queued, run it now. */
3196 reset_ecs (ecs
, tp
);
3197 switch_to_thread (tp
->ptid
);
3198 keep_going_pass_signal (ecs
);
3199 if (!ecs
->wait_some_more
)
3200 error (_("Command aborted."));
3203 do_cleanups (defer_resume_cleanup
);
3204 target_commit_resume ();
3206 discard_cleanups (old_chain
);
3208 /* Tell the event loop to wait for it to stop. If the target
3209 supports asynchronous execution, it'll do this from within
3211 if (!target_can_async_p ())
3212 mark_async_event_handler (infrun_async_inferior_event_token
);
3216 /* Start remote-debugging of a machine over a serial link. */
3219 start_remote (int from_tty
)
3221 struct inferior
*inferior
;
3223 inferior
= current_inferior ();
3224 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3226 /* Always go on waiting for the target, regardless of the mode. */
3227 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3228 indicate to wait_for_inferior that a target should timeout if
3229 nothing is returned (instead of just blocking). Because of this,
3230 targets expecting an immediate response need to, internally, set
3231 things up so that the target_wait() is forced to eventually
3233 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3234 differentiate to its caller what the state of the target is after
3235 the initial open has been performed. Here we're assuming that
3236 the target has stopped. It should be possible to eventually have
3237 target_open() return to the caller an indication that the target
3238 is currently running and GDB state should be set to the same as
3239 for an async run. */
3240 wait_for_inferior ();
3242 /* Now that the inferior has stopped, do any bookkeeping like
3243 loading shared libraries. We want to do this before normal_stop,
3244 so that the displayed frame is up to date. */
3245 post_create_inferior (¤t_target
, from_tty
);
3250 /* Initialize static vars when a new inferior begins. */
3253 init_wait_for_inferior (void)
3255 /* These are meaningless until the first time through wait_for_inferior. */
3257 breakpoint_init_inferior (inf_starting
);
3259 clear_proceed_status (0);
3261 target_last_wait_ptid
= minus_one_ptid
;
3263 previous_inferior_ptid
= inferior_ptid
;
3265 /* Discard any skipped inlined frames. */
3266 clear_inline_frame_state (minus_one_ptid
);
3271 static void handle_inferior_event (struct execution_control_state
*ecs
);
3273 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3274 struct execution_control_state
*ecs
);
3275 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3276 struct execution_control_state
*ecs
);
3277 static void handle_signal_stop (struct execution_control_state
*ecs
);
3278 static void check_exception_resume (struct execution_control_state
*,
3279 struct frame_info
*);
3281 static void end_stepping_range (struct execution_control_state
*ecs
);
3282 static void stop_waiting (struct execution_control_state
*ecs
);
3283 static void keep_going (struct execution_control_state
*ecs
);
3284 static void process_event_stop_test (struct execution_control_state
*ecs
);
3285 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3287 /* This function is attached as a "thread_stop_requested" observer.
3288 Cleanup local state that assumed the PTID was to be resumed, and
3289 report the stop to the frontend. */
3292 infrun_thread_stop_requested (ptid_t ptid
)
3294 struct thread_info
*tp
;
3296 /* PTID was requested to stop. If the thread was already stopped,
3297 but the user/frontend doesn't know about that yet (e.g., the
3298 thread had been temporarily paused for some step-over), set up
3299 for reporting the stop now. */
3300 ALL_NON_EXITED_THREADS (tp
)
3301 if (ptid_match (tp
->ptid
, ptid
))
3303 if (tp
->state
!= THREAD_RUNNING
)
3308 /* Remove matching threads from the step-over queue, so
3309 start_step_over doesn't try to resume them
3311 if (thread_is_in_step_over_chain (tp
))
3312 thread_step_over_chain_remove (tp
);
3314 /* If the thread is stopped, but the user/frontend doesn't
3315 know about that yet, queue a pending event, as if the
3316 thread had just stopped now. Unless the thread already had
3318 if (!tp
->suspend
.waitstatus_pending_p
)
3320 tp
->suspend
.waitstatus_pending_p
= 1;
3321 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_STOPPED
;
3322 tp
->suspend
.waitstatus
.value
.sig
= GDB_SIGNAL_0
;
3325 /* Clear the inline-frame state, since we're re-processing the
3327 clear_inline_frame_state (tp
->ptid
);
3329 /* If this thread was paused because some other thread was
3330 doing an inline-step over, let that finish first. Once
3331 that happens, we'll restart all threads and consume pending
3332 stop events then. */
3333 if (step_over_info_valid_p ())
3336 /* Otherwise we can process the (new) pending event now. Set
3337 it so this pending event is considered by
3344 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3346 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3347 nullify_last_target_wait_ptid ();
3350 /* Delete the step resume, single-step and longjmp/exception resume
3351 breakpoints of TP. */
3354 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3356 delete_step_resume_breakpoint (tp
);
3357 delete_exception_resume_breakpoint (tp
);
3358 delete_single_step_breakpoints (tp
);
3361 /* If the target still has execution, call FUNC for each thread that
3362 just stopped. In all-stop, that's all the non-exited threads; in
3363 non-stop, that's the current thread, only. */
3365 typedef void (*for_each_just_stopped_thread_callback_func
)
3366 (struct thread_info
*tp
);
3369 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3371 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3374 if (target_is_non_stop_p ())
3376 /* If in non-stop mode, only the current thread stopped. */
3377 func (inferior_thread ());
3381 struct thread_info
*tp
;
3383 /* In all-stop mode, all threads have stopped. */
3384 ALL_NON_EXITED_THREADS (tp
)
3391 /* Delete the step resume and longjmp/exception resume breakpoints of
3392 the threads that just stopped. */
3395 delete_just_stopped_threads_infrun_breakpoints (void)
3397 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3400 /* Delete the single-step breakpoints of the threads that just
3404 delete_just_stopped_threads_single_step_breakpoints (void)
3406 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3409 /* A cleanup wrapper. */
3412 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3414 delete_just_stopped_threads_infrun_breakpoints ();
3420 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3421 const struct target_waitstatus
*ws
)
3423 std::string status_string
= target_waitstatus_to_string (ws
);
3426 /* The text is split over several lines because it was getting too long.
3427 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3428 output as a unit; we want only one timestamp printed if debug_timestamp
3431 stb
.printf ("infrun: target_wait (%d.%ld.%ld",
3432 ptid_get_pid (waiton_ptid
),
3433 ptid_get_lwp (waiton_ptid
),
3434 ptid_get_tid (waiton_ptid
));
3435 if (ptid_get_pid (waiton_ptid
) != -1)
3436 stb
.printf (" [%s]", target_pid_to_str (waiton_ptid
));
3437 stb
.printf (", status) =\n");
3438 stb
.printf ("infrun: %d.%ld.%ld [%s],\n",
3439 ptid_get_pid (result_ptid
),
3440 ptid_get_lwp (result_ptid
),
3441 ptid_get_tid (result_ptid
),
3442 target_pid_to_str (result_ptid
));
3443 stb
.printf ("infrun: %s\n", status_string
.c_str ());
3445 /* This uses %s in part to handle %'s in the text, but also to avoid
3446 a gcc error: the format attribute requires a string literal. */
3447 fprintf_unfiltered (gdb_stdlog
, "%s", stb
.c_str ());
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
;
3570 = 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
));
3578 /* Now that we've selected our final event LWP, un-adjust its PC
3579 if it was a software breakpoint (and the target doesn't
3580 always adjust the PC itself). */
3581 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3582 && !target_supports_stopped_by_sw_breakpoint ())
3584 struct regcache
*regcache
;
3585 struct gdbarch
*gdbarch
;
3588 regcache
= get_thread_regcache (tp
->ptid
);
3589 gdbarch
= get_regcache_arch (regcache
);
3591 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3596 pc
= regcache_read_pc (regcache
);
3597 regcache_write_pc (regcache
, pc
+ decr_pc
);
3601 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3602 *status
= tp
->suspend
.waitstatus
;
3603 tp
->suspend
.waitstatus_pending_p
= 0;
3605 /* Wake up the event loop again, until all pending events are
3607 if (target_is_async_p ())
3608 mark_async_event_handler (infrun_async_inferior_event_token
);
3612 /* But if we don't find one, we'll have to wait. */
3614 if (deprecated_target_wait_hook
)
3615 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3617 event_ptid
= target_wait (ptid
, status
, options
);
3622 /* Prepare and stabilize the inferior for detaching it. E.g.,
3623 detaching while a thread is displaced stepping is a recipe for
3624 crashing it, as nothing would readjust the PC out of the scratch
3628 prepare_for_detach (void)
3630 struct inferior
*inf
= current_inferior ();
3631 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3632 struct displaced_step_inferior_state
*displaced
;
3634 displaced
= get_displaced_stepping_state (inf
->pid
);
3636 /* Is any thread of this process displaced stepping? If not,
3637 there's nothing else to do. */
3638 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3642 fprintf_unfiltered (gdb_stdlog
,
3643 "displaced-stepping in-process while detaching");
3645 scoped_restore restore_detaching
= make_scoped_restore (&inf
->detaching
, true);
3647 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3649 struct cleanup
*old_chain_2
;
3650 struct execution_control_state ecss
;
3651 struct execution_control_state
*ecs
;
3654 memset (ecs
, 0, sizeof (*ecs
));
3656 overlay_cache_invalid
= 1;
3657 /* Flush target cache before starting to handle each event.
3658 Target was running and cache could be stale. This is just a
3659 heuristic. Running threads may modify target memory, but we
3660 don't get any event. */
3661 target_dcache_invalidate ();
3663 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3666 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3668 /* If an error happens while handling the event, propagate GDB's
3669 knowledge of the executing state to the frontend/user running
3671 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3674 /* Now figure out what to do with the result of the result. */
3675 handle_inferior_event (ecs
);
3677 /* No error, don't finish the state yet. */
3678 discard_cleanups (old_chain_2
);
3680 /* Breakpoints and watchpoints are not installed on the target
3681 at this point, and signals are passed directly to the
3682 inferior, so this must mean the process is gone. */
3683 if (!ecs
->wait_some_more
)
3685 restore_detaching
.release ();
3686 error (_("Program exited while detaching"));
3690 restore_detaching
.release ();
3693 /* Wait for control to return from inferior to debugger.
3695 If inferior gets a signal, we may decide to start it up again
3696 instead of returning. That is why there is a loop in this function.
3697 When this function actually returns it means the inferior
3698 should be left stopped and GDB should read more commands. */
3701 wait_for_inferior (void)
3703 struct cleanup
*old_cleanups
;
3704 struct cleanup
*thread_state_chain
;
3708 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3711 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3714 /* If an error happens while handling the event, propagate GDB's
3715 knowledge of the executing state to the frontend/user running
3717 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3721 struct execution_control_state ecss
;
3722 struct execution_control_state
*ecs
= &ecss
;
3723 ptid_t waiton_ptid
= minus_one_ptid
;
3725 memset (ecs
, 0, sizeof (*ecs
));
3727 overlay_cache_invalid
= 1;
3729 /* Flush target cache before starting to handle each event.
3730 Target was running and cache could be stale. This is just a
3731 heuristic. Running threads may modify target memory, but we
3732 don't get any event. */
3733 target_dcache_invalidate ();
3735 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3738 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3740 /* Now figure out what to do with the result of the result. */
3741 handle_inferior_event (ecs
);
3743 if (!ecs
->wait_some_more
)
3747 /* No error, don't finish the state yet. */
3748 discard_cleanups (thread_state_chain
);
3750 do_cleanups (old_cleanups
);
3753 /* Cleanup that reinstalls the readline callback handler, if the
3754 target is running in the background. If while handling the target
3755 event something triggered a secondary prompt, like e.g., a
3756 pagination prompt, we'll have removed the callback handler (see
3757 gdb_readline_wrapper_line). Need to do this as we go back to the
3758 event loop, ready to process further input. Note this has no
3759 effect if the handler hasn't actually been removed, because calling
3760 rl_callback_handler_install resets the line buffer, thus losing
3764 reinstall_readline_callback_handler_cleanup (void *arg
)
3766 struct ui
*ui
= current_ui
;
3770 /* We're not going back to the top level event loop yet. Don't
3771 install the readline callback, as it'd prep the terminal,
3772 readline-style (raw, noecho) (e.g., --batch). We'll install
3773 it the next time the prompt is displayed, when we're ready
3778 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3779 gdb_rl_callback_handler_reinstall ();
3782 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3783 that's just the event thread. In all-stop, that's all threads. */
3786 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3788 struct thread_info
*thr
= ecs
->event_thread
;
3790 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3791 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3795 ALL_NON_EXITED_THREADS (thr
)
3797 if (thr
->thread_fsm
== NULL
)
3799 if (thr
== ecs
->event_thread
)
3802 switch_to_thread (thr
->ptid
);
3803 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3806 if (ecs
->event_thread
!= NULL
)
3807 switch_to_thread (ecs
->event_thread
->ptid
);
3811 /* Helper for all_uis_check_sync_execution_done that works on the
3815 check_curr_ui_sync_execution_done (void)
3817 struct ui
*ui
= current_ui
;
3819 if (ui
->prompt_state
== PROMPT_NEEDED
3821 && !gdb_in_secondary_prompt_p (ui
))
3823 target_terminal_ours ();
3824 observer_notify_sync_execution_done ();
3825 ui_register_input_event_handler (ui
);
3832 all_uis_check_sync_execution_done (void)
3834 SWITCH_THRU_ALL_UIS ()
3836 check_curr_ui_sync_execution_done ();
3843 all_uis_on_sync_execution_starting (void)
3845 SWITCH_THRU_ALL_UIS ()
3847 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3848 async_disable_stdin ();
3852 /* Asynchronous version of wait_for_inferior. It is called by the
3853 event loop whenever a change of state is detected on the file
3854 descriptor corresponding to the target. It can be called more than
3855 once to complete a single execution command. In such cases we need
3856 to keep the state in a global variable ECSS. If it is the last time
3857 that this function is called for a single execution command, then
3858 report to the user that the inferior has stopped, and do the
3859 necessary cleanups. */
3862 fetch_inferior_event (void *client_data
)
3864 struct execution_control_state ecss
;
3865 struct execution_control_state
*ecs
= &ecss
;
3866 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3867 struct cleanup
*ts_old_chain
;
3869 ptid_t waiton_ptid
= minus_one_ptid
;
3871 memset (ecs
, 0, sizeof (*ecs
));
3873 /* Events are always processed with the main UI as current UI. This
3874 way, warnings, debug output, etc. are always consistently sent to
3875 the main console. */
3876 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3878 /* End up with readline processing input, if necessary. */
3879 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3881 /* We're handling a live event, so make sure we're doing live
3882 debugging. If we're looking at traceframes while the target is
3883 running, we're going to need to get back to that mode after
3884 handling the event. */
3887 make_cleanup_restore_current_traceframe ();
3888 set_current_traceframe (-1);
3891 gdb::optional
<scoped_restore_current_thread
> maybe_restore_thread
;
3894 /* In non-stop mode, the user/frontend should not notice a thread
3895 switch due to internal events. Make sure we reverse to the
3896 user selected thread and frame after handling the event and
3897 running any breakpoint commands. */
3898 maybe_restore_thread
.emplace ();
3900 overlay_cache_invalid
= 1;
3901 /* Flush target cache before starting to handle each event. Target
3902 was running and cache could be stale. This is just a heuristic.
3903 Running threads may modify target memory, but we don't get any
3905 target_dcache_invalidate ();
3907 scoped_restore save_exec_dir
3908 = make_scoped_restore (&execution_direction
, target_execution_direction ());
3910 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3911 target_can_async_p () ? TARGET_WNOHANG
: 0);
3914 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3916 /* If an error happens while handling the event, propagate GDB's
3917 knowledge of the executing state to the frontend/user running
3919 if (!target_is_non_stop_p ())
3920 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3922 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3924 /* Get executed before make_cleanup_restore_current_thread above to apply
3925 still for the thread which has thrown the exception. */
3926 make_bpstat_clear_actions_cleanup ();
3928 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3930 /* Now figure out what to do with the result of the result. */
3931 handle_inferior_event (ecs
);
3933 if (!ecs
->wait_some_more
)
3935 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3936 int should_stop
= 1;
3937 struct thread_info
*thr
= ecs
->event_thread
;
3938 int should_notify_stop
= 1;
3940 delete_just_stopped_threads_infrun_breakpoints ();
3944 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3946 if (thread_fsm
!= NULL
)
3947 should_stop
= thread_fsm_should_stop (thread_fsm
, thr
);
3956 clean_up_just_stopped_threads_fsms (ecs
);
3958 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3961 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
3964 if (should_notify_stop
)
3968 /* We may not find an inferior if this was a process exit. */
3969 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3970 proceeded
= normal_stop ();
3974 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3981 /* No error, don't finish the thread states yet. */
3982 discard_cleanups (ts_old_chain
);
3984 /* Revert thread and frame. */
3985 do_cleanups (old_chain
);
3987 /* If a UI was in sync execution mode, and now isn't, restore its
3988 prompt (a synchronous execution command has finished, and we're
3989 ready for input). */
3990 all_uis_check_sync_execution_done ();
3993 && exec_done_display_p
3994 && (ptid_equal (inferior_ptid
, null_ptid
)
3995 || !is_running (inferior_ptid
)))
3996 printf_unfiltered (_("completed.\n"));
3999 /* Record the frame and location we're currently stepping through. */
4001 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
4003 struct thread_info
*tp
= inferior_thread ();
4005 tp
->control
.step_frame_id
= get_frame_id (frame
);
4006 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4008 tp
->current_symtab
= sal
.symtab
;
4009 tp
->current_line
= sal
.line
;
4012 /* Clear context switchable stepping state. */
4015 init_thread_stepping_state (struct thread_info
*tss
)
4017 tss
->stepped_breakpoint
= 0;
4018 tss
->stepping_over_breakpoint
= 0;
4019 tss
->stepping_over_watchpoint
= 0;
4020 tss
->step_after_step_resume_breakpoint
= 0;
4023 /* Set the cached copy of the last ptid/waitstatus. */
4026 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
4028 target_last_wait_ptid
= ptid
;
4029 target_last_waitstatus
= status
;
4032 /* Return the cached copy of the last pid/waitstatus returned by
4033 target_wait()/deprecated_target_wait_hook(). The data is actually
4034 cached by handle_inferior_event(), which gets called immediately
4035 after target_wait()/deprecated_target_wait_hook(). */
4038 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
4040 *ptidp
= target_last_wait_ptid
;
4041 *status
= target_last_waitstatus
;
4045 nullify_last_target_wait_ptid (void)
4047 target_last_wait_ptid
= minus_one_ptid
;
4050 /* Switch thread contexts. */
4053 context_switch (ptid_t ptid
)
4055 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4057 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4058 target_pid_to_str (inferior_ptid
));
4059 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4060 target_pid_to_str (ptid
));
4063 switch_to_thread (ptid
);
4066 /* If the target can't tell whether we've hit breakpoints
4067 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4068 check whether that could have been caused by a breakpoint. If so,
4069 adjust the PC, per gdbarch_decr_pc_after_break. */
4072 adjust_pc_after_break (struct thread_info
*thread
,
4073 struct target_waitstatus
*ws
)
4075 struct regcache
*regcache
;
4076 struct gdbarch
*gdbarch
;
4077 struct address_space
*aspace
;
4078 CORE_ADDR breakpoint_pc
, decr_pc
;
4080 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4081 we aren't, just return.
4083 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4084 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4085 implemented by software breakpoints should be handled through the normal
4088 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4089 different signals (SIGILL or SIGEMT for instance), but it is less
4090 clear where the PC is pointing afterwards. It may not match
4091 gdbarch_decr_pc_after_break. I don't know any specific target that
4092 generates these signals at breakpoints (the code has been in GDB since at
4093 least 1992) so I can not guess how to handle them here.
4095 In earlier versions of GDB, a target with
4096 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4097 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4098 target with both of these set in GDB history, and it seems unlikely to be
4099 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4101 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4104 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4107 /* In reverse execution, when a breakpoint is hit, the instruction
4108 under it has already been de-executed. The reported PC always
4109 points at the breakpoint address, so adjusting it further would
4110 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4113 B1 0x08000000 : INSN1
4114 B2 0x08000001 : INSN2
4116 PC -> 0x08000003 : INSN4
4118 Say you're stopped at 0x08000003 as above. Reverse continuing
4119 from that point should hit B2 as below. Reading the PC when the
4120 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4121 been de-executed already.
4123 B1 0x08000000 : INSN1
4124 B2 PC -> 0x08000001 : INSN2
4128 We can't apply the same logic as for forward execution, because
4129 we would wrongly adjust the PC to 0x08000000, since there's a
4130 breakpoint at PC - 1. We'd then report a hit on B1, although
4131 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4133 if (execution_direction
== EXEC_REVERSE
)
4136 /* If the target can tell whether the thread hit a SW breakpoint,
4137 trust it. Targets that can tell also adjust the PC
4139 if (target_supports_stopped_by_sw_breakpoint ())
4142 /* Note that relying on whether a breakpoint is planted in memory to
4143 determine this can fail. E.g,. the breakpoint could have been
4144 removed since. Or the thread could have been told to step an
4145 instruction the size of a breakpoint instruction, and only
4146 _after_ was a breakpoint inserted at its address. */
4148 /* If this target does not decrement the PC after breakpoints, then
4149 we have nothing to do. */
4150 regcache
= get_thread_regcache (thread
->ptid
);
4151 gdbarch
= get_regcache_arch (regcache
);
4153 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4157 aspace
= get_regcache_aspace (regcache
);
4159 /* Find the location where (if we've hit a breakpoint) the
4160 breakpoint would be. */
4161 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4163 /* If the target can't tell whether a software breakpoint triggered,
4164 fallback to figuring it out based on breakpoints we think were
4165 inserted in the target, and on whether the thread was stepped or
4168 /* Check whether there actually is a software breakpoint inserted at
4171 If in non-stop mode, a race condition is possible where we've
4172 removed a breakpoint, but stop events for that breakpoint were
4173 already queued and arrive later. To suppress those spurious
4174 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4175 and retire them after a number of stop events are reported. Note
4176 this is an heuristic and can thus get confused. The real fix is
4177 to get the "stopped by SW BP and needs adjustment" info out of
4178 the target/kernel (and thus never reach here; see above). */
4179 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4180 || (target_is_non_stop_p ()
4181 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4183 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4185 if (record_full_is_used ())
4186 record_full_gdb_operation_disable_set ();
4188 /* When using hardware single-step, a SIGTRAP is reported for both
4189 a completed single-step and a software breakpoint. Need to
4190 differentiate between the two, as the latter needs adjusting
4191 but the former does not.
4193 The SIGTRAP can be due to a completed hardware single-step only if
4194 - we didn't insert software single-step breakpoints
4195 - this thread is currently being stepped
4197 If any of these events did not occur, we must have stopped due
4198 to hitting a software breakpoint, and have to back up to the
4201 As a special case, we could have hardware single-stepped a
4202 software breakpoint. In this case (prev_pc == breakpoint_pc),
4203 we also need to back up to the breakpoint address. */
4205 if (thread_has_single_step_breakpoints_set (thread
)
4206 || !currently_stepping (thread
)
4207 || (thread
->stepped_breakpoint
4208 && thread
->prev_pc
== breakpoint_pc
))
4209 regcache_write_pc (regcache
, breakpoint_pc
);
4211 do_cleanups (old_cleanups
);
4216 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4218 for (frame
= get_prev_frame (frame
);
4220 frame
= get_prev_frame (frame
))
4222 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4224 if (get_frame_type (frame
) != INLINE_FRAME
)
4231 /* If the event thread has the stop requested flag set, pretend it
4232 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4236 handle_stop_requested (struct execution_control_state
*ecs
)
4238 if (ecs
->event_thread
->stop_requested
)
4240 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4241 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4242 handle_signal_stop (ecs
);
4248 /* Auxiliary function that handles syscall entry/return events.
4249 It returns 1 if the inferior should keep going (and GDB
4250 should ignore the event), or 0 if the event deserves to be
4254 handle_syscall_event (struct execution_control_state
*ecs
)
4256 struct regcache
*regcache
;
4259 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4260 context_switch (ecs
->ptid
);
4262 regcache
= get_thread_regcache (ecs
->ptid
);
4263 syscall_number
= ecs
->ws
.value
.syscall_number
;
4264 stop_pc
= regcache_read_pc (regcache
);
4266 if (catch_syscall_enabled () > 0
4267 && catching_syscall_number (syscall_number
) > 0)
4270 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4273 ecs
->event_thread
->control
.stop_bpstat
4274 = bpstat_stop_status (get_regcache_aspace (regcache
),
4275 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4277 if (handle_stop_requested (ecs
))
4280 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4282 /* Catchpoint hit. */
4287 if (handle_stop_requested (ecs
))
4290 /* If no catchpoint triggered for this, then keep going. */
4295 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4298 fill_in_stop_func (struct gdbarch
*gdbarch
,
4299 struct execution_control_state
*ecs
)
4301 if (!ecs
->stop_func_filled_in
)
4303 /* Don't care about return value; stop_func_start and stop_func_name
4304 will both be 0 if it doesn't work. */
4305 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4306 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4307 ecs
->stop_func_start
4308 += gdbarch_deprecated_function_start_offset (gdbarch
);
4310 if (gdbarch_skip_entrypoint_p (gdbarch
))
4311 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4312 ecs
->stop_func_start
);
4314 ecs
->stop_func_filled_in
= 1;
4319 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4321 static enum stop_kind
4322 get_inferior_stop_soon (ptid_t ptid
)
4324 struct inferior
*inf
= find_inferior_ptid (ptid
);
4326 gdb_assert (inf
!= NULL
);
4327 return inf
->control
.stop_soon
;
4330 /* Wait for one event. Store the resulting waitstatus in WS, and
4331 return the event ptid. */
4334 wait_one (struct target_waitstatus
*ws
)
4337 ptid_t wait_ptid
= minus_one_ptid
;
4339 overlay_cache_invalid
= 1;
4341 /* Flush target cache before starting to handle each event.
4342 Target was running and cache could be stale. This is just a
4343 heuristic. Running threads may modify target memory, but we
4344 don't get any event. */
4345 target_dcache_invalidate ();
4347 if (deprecated_target_wait_hook
)
4348 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4350 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4353 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4358 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4359 instead of the current thread. */
4360 #define THREAD_STOPPED_BY(REASON) \
4362 thread_stopped_by_ ## REASON (ptid_t ptid) \
4364 scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid); \
4365 inferior_ptid = ptid; \
4367 return target_stopped_by_ ## REASON (); \
4370 /* Generate thread_stopped_by_watchpoint. */
4371 THREAD_STOPPED_BY (watchpoint
)
4372 /* Generate thread_stopped_by_sw_breakpoint. */
4373 THREAD_STOPPED_BY (sw_breakpoint
)
4374 /* Generate thread_stopped_by_hw_breakpoint. */
4375 THREAD_STOPPED_BY (hw_breakpoint
)
4377 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4380 switch_to_thread_cleanup (void *ptid_p
)
4382 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4384 switch_to_thread (ptid
);
4387 /* Save the thread's event and stop reason to process it later. */
4390 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4392 struct regcache
*regcache
;
4393 struct address_space
*aspace
;
4397 std::string statstr
= target_waitstatus_to_string (ws
);
4399 fprintf_unfiltered (gdb_stdlog
,
4400 "infrun: saving status %s for %d.%ld.%ld\n",
4402 ptid_get_pid (tp
->ptid
),
4403 ptid_get_lwp (tp
->ptid
),
4404 ptid_get_tid (tp
->ptid
));
4407 /* Record for later. */
4408 tp
->suspend
.waitstatus
= *ws
;
4409 tp
->suspend
.waitstatus_pending_p
= 1;
4411 regcache
= get_thread_regcache (tp
->ptid
);
4412 aspace
= get_regcache_aspace (regcache
);
4414 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4415 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4417 CORE_ADDR pc
= regcache_read_pc (regcache
);
4419 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4421 if (thread_stopped_by_watchpoint (tp
->ptid
))
4423 tp
->suspend
.stop_reason
4424 = TARGET_STOPPED_BY_WATCHPOINT
;
4426 else if (target_supports_stopped_by_sw_breakpoint ()
4427 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4429 tp
->suspend
.stop_reason
4430 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4432 else if (target_supports_stopped_by_hw_breakpoint ()
4433 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4435 tp
->suspend
.stop_reason
4436 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4438 else if (!target_supports_stopped_by_hw_breakpoint ()
4439 && hardware_breakpoint_inserted_here_p (aspace
,
4442 tp
->suspend
.stop_reason
4443 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4445 else if (!target_supports_stopped_by_sw_breakpoint ()
4446 && software_breakpoint_inserted_here_p (aspace
,
4449 tp
->suspend
.stop_reason
4450 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4452 else if (!thread_has_single_step_breakpoints_set (tp
)
4453 && currently_stepping (tp
))
4455 tp
->suspend
.stop_reason
4456 = TARGET_STOPPED_BY_SINGLE_STEP
;
4461 /* A cleanup that disables thread create/exit events. */
4464 disable_thread_events (void *arg
)
4466 target_thread_events (0);
4472 stop_all_threads (void)
4474 /* We may need multiple passes to discover all threads. */
4478 struct cleanup
*old_chain
;
4480 gdb_assert (target_is_non_stop_p ());
4483 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4485 entry_ptid
= inferior_ptid
;
4486 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4488 target_thread_events (1);
4489 make_cleanup (disable_thread_events
, NULL
);
4491 /* Request threads to stop, and then wait for the stops. Because
4492 threads we already know about can spawn more threads while we're
4493 trying to stop them, and we only learn about new threads when we
4494 update the thread list, do this in a loop, and keep iterating
4495 until two passes find no threads that need to be stopped. */
4496 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4499 fprintf_unfiltered (gdb_stdlog
,
4500 "infrun: stop_all_threads, pass=%d, "
4501 "iterations=%d\n", pass
, iterations
);
4505 struct target_waitstatus ws
;
4507 struct thread_info
*t
;
4509 update_thread_list ();
4511 /* Go through all threads looking for threads that we need
4512 to tell the target to stop. */
4513 ALL_NON_EXITED_THREADS (t
)
4517 /* If already stopping, don't request a stop again.
4518 We just haven't seen the notification yet. */
4519 if (!t
->stop_requested
)
4522 fprintf_unfiltered (gdb_stdlog
,
4523 "infrun: %s executing, "
4525 target_pid_to_str (t
->ptid
));
4526 target_stop (t
->ptid
);
4527 t
->stop_requested
= 1;
4532 fprintf_unfiltered (gdb_stdlog
,
4533 "infrun: %s executing, "
4534 "already stopping\n",
4535 target_pid_to_str (t
->ptid
));
4538 if (t
->stop_requested
)
4544 fprintf_unfiltered (gdb_stdlog
,
4545 "infrun: %s not executing\n",
4546 target_pid_to_str (t
->ptid
));
4548 /* The thread may be not executing, but still be
4549 resumed with a pending status to process. */
4557 /* If we find new threads on the second iteration, restart
4558 over. We want to see two iterations in a row with all
4563 event_ptid
= wait_one (&ws
);
4564 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4566 /* All resumed threads exited. */
4568 else if (ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4569 || ws
.kind
== TARGET_WAITKIND_EXITED
4570 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4574 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4576 fprintf_unfiltered (gdb_stdlog
,
4577 "infrun: %s exited while "
4578 "stopping threads\n",
4579 target_pid_to_str (ptid
));
4584 struct inferior
*inf
;
4586 t
= find_thread_ptid (event_ptid
);
4588 t
= add_thread (event_ptid
);
4590 t
->stop_requested
= 0;
4593 t
->control
.may_range_step
= 0;
4595 /* This may be the first time we see the inferior report
4597 inf
= find_inferior_ptid (event_ptid
);
4598 if (inf
->needs_setup
)
4600 switch_to_thread_no_regs (t
);
4604 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4605 && ws
.value
.sig
== GDB_SIGNAL_0
)
4607 /* We caught the event that we intended to catch, so
4608 there's no event pending. */
4609 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4610 t
->suspend
.waitstatus_pending_p
= 0;
4612 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4614 /* Add it back to the step-over queue. */
4617 fprintf_unfiltered (gdb_stdlog
,
4618 "infrun: displaced-step of %s "
4619 "canceled: adding back to the "
4620 "step-over queue\n",
4621 target_pid_to_str (t
->ptid
));
4623 t
->control
.trap_expected
= 0;
4624 thread_step_over_chain_enqueue (t
);
4629 enum gdb_signal sig
;
4630 struct regcache
*regcache
;
4634 std::string statstr
= target_waitstatus_to_string (&ws
);
4636 fprintf_unfiltered (gdb_stdlog
,
4637 "infrun: target_wait %s, saving "
4638 "status for %d.%ld.%ld\n",
4640 ptid_get_pid (t
->ptid
),
4641 ptid_get_lwp (t
->ptid
),
4642 ptid_get_tid (t
->ptid
));
4645 /* Record for later. */
4646 save_waitstatus (t
, &ws
);
4648 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4649 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4651 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4653 /* Add it back to the step-over queue. */
4654 t
->control
.trap_expected
= 0;
4655 thread_step_over_chain_enqueue (t
);
4658 regcache
= get_thread_regcache (t
->ptid
);
4659 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4663 fprintf_unfiltered (gdb_stdlog
,
4664 "infrun: saved stop_pc=%s for %s "
4665 "(currently_stepping=%d)\n",
4666 paddress (target_gdbarch (),
4667 t
->suspend
.stop_pc
),
4668 target_pid_to_str (t
->ptid
),
4669 currently_stepping (t
));
4676 do_cleanups (old_chain
);
4679 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4682 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4685 handle_no_resumed (struct execution_control_state
*ecs
)
4687 struct inferior
*inf
;
4688 struct thread_info
*thread
;
4690 if (target_can_async_p ())
4697 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4705 /* There were no unwaited-for children left in the target, but,
4706 we're not synchronously waiting for events either. Just
4710 fprintf_unfiltered (gdb_stdlog
,
4711 "infrun: TARGET_WAITKIND_NO_RESUMED "
4712 "(ignoring: bg)\n");
4713 prepare_to_wait (ecs
);
4718 /* Otherwise, if we were running a synchronous execution command, we
4719 may need to cancel it and give the user back the terminal.
4721 In non-stop mode, the target can't tell whether we've already
4722 consumed previous stop events, so it can end up sending us a
4723 no-resumed event like so:
4725 #0 - thread 1 is left stopped
4727 #1 - thread 2 is resumed and hits breakpoint
4728 -> TARGET_WAITKIND_STOPPED
4730 #2 - thread 3 is resumed and exits
4731 this is the last resumed thread, so
4732 -> TARGET_WAITKIND_NO_RESUMED
4734 #3 - gdb processes stop for thread 2 and decides to re-resume
4737 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4738 thread 2 is now resumed, so the event should be ignored.
4740 IOW, if the stop for thread 2 doesn't end a foreground command,
4741 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4742 event. But it could be that the event meant that thread 2 itself
4743 (or whatever other thread was the last resumed thread) exited.
4745 To address this we refresh the thread list and check whether we
4746 have resumed threads _now_. In the example above, this removes
4747 thread 3 from the thread list. If thread 2 was re-resumed, we
4748 ignore this event. If we find no thread resumed, then we cancel
4749 the synchronous command show "no unwaited-for " to the user. */
4750 update_thread_list ();
4752 ALL_NON_EXITED_THREADS (thread
)
4754 if (thread
->executing
4755 || thread
->suspend
.waitstatus_pending_p
)
4757 /* There were no unwaited-for children left in the target at
4758 some point, but there are now. Just ignore. */
4760 fprintf_unfiltered (gdb_stdlog
,
4761 "infrun: TARGET_WAITKIND_NO_RESUMED "
4762 "(ignoring: found resumed)\n");
4763 prepare_to_wait (ecs
);
4768 /* Note however that we may find no resumed thread because the whole
4769 process exited meanwhile (thus updating the thread list results
4770 in an empty thread list). In this case we know we'll be getting
4771 a process exit event shortly. */
4777 thread
= any_live_thread_of_process (inf
->pid
);
4781 fprintf_unfiltered (gdb_stdlog
,
4782 "infrun: TARGET_WAITKIND_NO_RESUMED "
4783 "(expect process exit)\n");
4784 prepare_to_wait (ecs
);
4789 /* Go ahead and report the event. */
4793 /* Given an execution control state that has been freshly filled in by
4794 an event from the inferior, figure out what it means and take
4797 The alternatives are:
4799 1) stop_waiting and return; to really stop and return to the
4802 2) keep_going and return; to wait for the next event (set
4803 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4807 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4809 enum stop_kind stop_soon
;
4811 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4813 /* We had an event in the inferior, but we are not interested in
4814 handling it at this level. The lower layers have already
4815 done what needs to be done, if anything.
4817 One of the possible circumstances for this is when the
4818 inferior produces output for the console. The inferior has
4819 not stopped, and we are ignoring the event. Another possible
4820 circumstance is any event which the lower level knows will be
4821 reported multiple times without an intervening resume. */
4823 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4824 prepare_to_wait (ecs
);
4828 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4831 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4832 prepare_to_wait (ecs
);
4836 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4837 && handle_no_resumed (ecs
))
4840 /* Cache the last pid/waitstatus. */
4841 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4843 /* Always clear state belonging to the previous time we stopped. */
4844 stop_stack_dummy
= STOP_NONE
;
4846 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4848 /* No unwaited-for children left. IOW, all resumed children
4851 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4853 stop_print_frame
= 0;
4858 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4859 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4861 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4862 /* If it's a new thread, add it to the thread database. */
4863 if (ecs
->event_thread
== NULL
)
4864 ecs
->event_thread
= add_thread (ecs
->ptid
);
4866 /* Disable range stepping. If the next step request could use a
4867 range, this will be end up re-enabled then. */
4868 ecs
->event_thread
->control
.may_range_step
= 0;
4871 /* Dependent on valid ECS->EVENT_THREAD. */
4872 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4874 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4875 reinit_frame_cache ();
4877 breakpoint_retire_moribund ();
4879 /* First, distinguish signals caused by the debugger from signals
4880 that have to do with the program's own actions. Note that
4881 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4882 on the operating system version. Here we detect when a SIGILL or
4883 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4884 something similar for SIGSEGV, since a SIGSEGV will be generated
4885 when we're trying to execute a breakpoint instruction on a
4886 non-executable stack. This happens for call dummy breakpoints
4887 for architectures like SPARC that place call dummies on the
4889 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4890 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4891 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4892 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4894 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4896 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4897 regcache_read_pc (regcache
)))
4900 fprintf_unfiltered (gdb_stdlog
,
4901 "infrun: Treating signal as SIGTRAP\n");
4902 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4906 /* Mark the non-executing threads accordingly. In all-stop, all
4907 threads of all processes are stopped when we get any event
4908 reported. In non-stop mode, only the event thread stops. */
4912 if (!target_is_non_stop_p ())
4913 mark_ptid
= minus_one_ptid
;
4914 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4915 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4917 /* If we're handling a process exit in non-stop mode, even
4918 though threads haven't been deleted yet, one would think
4919 that there is nothing to do, as threads of the dead process
4920 will be soon deleted, and threads of any other process were
4921 left running. However, on some targets, threads survive a
4922 process exit event. E.g., for the "checkpoint" command,
4923 when the current checkpoint/fork exits, linux-fork.c
4924 automatically switches to another fork from within
4925 target_mourn_inferior, by associating the same
4926 inferior/thread to another fork. We haven't mourned yet at
4927 this point, but we must mark any threads left in the
4928 process as not-executing so that finish_thread_state marks
4929 them stopped (in the user's perspective) if/when we present
4930 the stop to the user. */
4931 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4934 mark_ptid
= ecs
->ptid
;
4936 set_executing (mark_ptid
, 0);
4938 /* Likewise the resumed flag. */
4939 set_resumed (mark_ptid
, 0);
4942 switch (ecs
->ws
.kind
)
4944 case TARGET_WAITKIND_LOADED
:
4946 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4947 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4948 context_switch (ecs
->ptid
);
4949 /* Ignore gracefully during startup of the inferior, as it might
4950 be the shell which has just loaded some objects, otherwise
4951 add the symbols for the newly loaded objects. Also ignore at
4952 the beginning of an attach or remote session; we will query
4953 the full list of libraries once the connection is
4956 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4957 if (stop_soon
== NO_STOP_QUIETLY
)
4959 struct regcache
*regcache
;
4961 regcache
= get_thread_regcache (ecs
->ptid
);
4963 handle_solib_event ();
4965 ecs
->event_thread
->control
.stop_bpstat
4966 = bpstat_stop_status (get_regcache_aspace (regcache
),
4967 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4969 if (handle_stop_requested (ecs
))
4972 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4974 /* A catchpoint triggered. */
4975 process_event_stop_test (ecs
);
4979 /* If requested, stop when the dynamic linker notifies
4980 gdb of events. This allows the user to get control
4981 and place breakpoints in initializer routines for
4982 dynamically loaded objects (among other things). */
4983 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4984 if (stop_on_solib_events
)
4986 /* Make sure we print "Stopped due to solib-event" in
4988 stop_print_frame
= 1;
4995 /* If we are skipping through a shell, or through shared library
4996 loading that we aren't interested in, resume the program. If
4997 we're running the program normally, also resume. */
4998 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5000 /* Loading of shared libraries might have changed breakpoint
5001 addresses. Make sure new breakpoints are inserted. */
5002 if (stop_soon
== NO_STOP_QUIETLY
)
5003 insert_breakpoints ();
5004 resume (GDB_SIGNAL_0
);
5005 prepare_to_wait (ecs
);
5009 /* But stop if we're attaching or setting up a remote
5011 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5012 || stop_soon
== STOP_QUIETLY_REMOTE
)
5015 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5020 internal_error (__FILE__
, __LINE__
,
5021 _("unhandled stop_soon: %d"), (int) stop_soon
);
5023 case TARGET_WAITKIND_SPURIOUS
:
5025 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5026 if (handle_stop_requested (ecs
))
5028 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5029 context_switch (ecs
->ptid
);
5030 resume (GDB_SIGNAL_0
);
5031 prepare_to_wait (ecs
);
5034 case TARGET_WAITKIND_THREAD_CREATED
:
5036 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5037 if (handle_stop_requested (ecs
))
5039 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5040 context_switch (ecs
->ptid
);
5041 if (!switch_back_to_stepped_thread (ecs
))
5045 case TARGET_WAITKIND_EXITED
:
5046 case TARGET_WAITKIND_SIGNALLED
:
5049 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5050 fprintf_unfiltered (gdb_stdlog
,
5051 "infrun: TARGET_WAITKIND_EXITED\n");
5053 fprintf_unfiltered (gdb_stdlog
,
5054 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5057 inferior_ptid
= ecs
->ptid
;
5058 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
5059 set_current_program_space (current_inferior ()->pspace
);
5060 handle_vfork_child_exec_or_exit (0);
5061 target_terminal_ours (); /* Must do this before mourn anyway. */
5063 /* Clearing any previous state of convenience variables. */
5064 clear_exit_convenience_vars ();
5066 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5068 /* Record the exit code in the convenience variable $_exitcode, so
5069 that the user can inspect this again later. */
5070 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5071 (LONGEST
) ecs
->ws
.value
.integer
);
5073 /* Also record this in the inferior itself. */
5074 current_inferior ()->has_exit_code
= 1;
5075 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5077 /* Support the --return-child-result option. */
5078 return_child_result_value
= ecs
->ws
.value
.integer
;
5080 observer_notify_exited (ecs
->ws
.value
.integer
);
5084 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5085 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5087 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5089 /* Set the value of the internal variable $_exitsignal,
5090 which holds the signal uncaught by the inferior. */
5091 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5092 gdbarch_gdb_signal_to_target (gdbarch
,
5093 ecs
->ws
.value
.sig
));
5097 /* We don't have access to the target's method used for
5098 converting between signal numbers (GDB's internal
5099 representation <-> target's representation).
5100 Therefore, we cannot do a good job at displaying this
5101 information to the user. It's better to just warn
5102 her about it (if infrun debugging is enabled), and
5105 fprintf_filtered (gdb_stdlog
, _("\
5106 Cannot fill $_exitsignal with the correct signal number.\n"));
5109 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
5112 gdb_flush (gdb_stdout
);
5113 target_mourn_inferior (inferior_ptid
);
5114 stop_print_frame
= 0;
5118 /* The following are the only cases in which we keep going;
5119 the above cases end in a continue or goto. */
5120 case TARGET_WAITKIND_FORKED
:
5121 case TARGET_WAITKIND_VFORKED
:
5124 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5125 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
5127 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
5130 /* Check whether the inferior is displaced stepping. */
5132 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5133 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5135 /* If checking displaced stepping is supported, and thread
5136 ecs->ptid is displaced stepping. */
5137 if (displaced_step_in_progress_thread (ecs
->ptid
))
5139 struct inferior
*parent_inf
5140 = find_inferior_ptid (ecs
->ptid
);
5141 struct regcache
*child_regcache
;
5142 CORE_ADDR parent_pc
;
5144 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5145 indicating that the displaced stepping of syscall instruction
5146 has been done. Perform cleanup for parent process here. Note
5147 that this operation also cleans up the child process for vfork,
5148 because their pages are shared. */
5149 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
5150 /* Start a new step-over in another thread if there's one
5154 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5156 struct displaced_step_inferior_state
*displaced
5157 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
5159 /* Restore scratch pad for child process. */
5160 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
5163 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5164 the child's PC is also within the scratchpad. Set the child's PC
5165 to the parent's PC value, which has already been fixed up.
5166 FIXME: we use the parent's aspace here, although we're touching
5167 the child, because the child hasn't been added to the inferior
5168 list yet at this point. */
5171 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
5173 parent_inf
->aspace
);
5174 /* Read PC value of parent process. */
5175 parent_pc
= regcache_read_pc (regcache
);
5177 if (debug_displaced
)
5178 fprintf_unfiltered (gdb_stdlog
,
5179 "displaced: write child pc from %s to %s\n",
5181 regcache_read_pc (child_regcache
)),
5182 paddress (gdbarch
, parent_pc
));
5184 regcache_write_pc (child_regcache
, parent_pc
);
5188 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5189 context_switch (ecs
->ptid
);
5191 /* Immediately detach breakpoints from the child before there's
5192 any chance of letting the user delete breakpoints from the
5193 breakpoint lists. If we don't do this early, it's easy to
5194 leave left over traps in the child, vis: "break foo; catch
5195 fork; c; <fork>; del; c; <child calls foo>". We only follow
5196 the fork on the last `continue', and by that time the
5197 breakpoint at "foo" is long gone from the breakpoint table.
5198 If we vforked, then we don't need to unpatch here, since both
5199 parent and child are sharing the same memory pages; we'll
5200 need to unpatch at follow/detach time instead to be certain
5201 that new breakpoints added between catchpoint hit time and
5202 vfork follow are detached. */
5203 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5205 /* This won't actually modify the breakpoint list, but will
5206 physically remove the breakpoints from the child. */
5207 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5210 delete_just_stopped_threads_single_step_breakpoints ();
5212 /* In case the event is caught by a catchpoint, remember that
5213 the event is to be followed at the next resume of the thread,
5214 and not immediately. */
5215 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5217 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5219 ecs
->event_thread
->control
.stop_bpstat
5220 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5221 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5223 if (handle_stop_requested (ecs
))
5226 /* If no catchpoint triggered for this, then keep going. Note
5227 that we're interested in knowing the bpstat actually causes a
5228 stop, not just if it may explain the signal. Software
5229 watchpoints, for example, always appear in the bpstat. */
5230 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5236 = (follow_fork_mode_string
== follow_fork_mode_child
);
5238 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5240 should_resume
= follow_fork ();
5243 child
= ecs
->ws
.value
.related_pid
;
5245 /* At this point, the parent is marked running, and the
5246 child is marked stopped. */
5248 /* If not resuming the parent, mark it stopped. */
5249 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5250 set_running (parent
, 0);
5252 /* If resuming the child, mark it running. */
5253 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5254 set_running (child
, 1);
5256 /* In non-stop mode, also resume the other branch. */
5257 if (!detach_fork
&& (non_stop
5258 || (sched_multi
&& target_is_non_stop_p ())))
5261 switch_to_thread (parent
);
5263 switch_to_thread (child
);
5265 ecs
->event_thread
= inferior_thread ();
5266 ecs
->ptid
= inferior_ptid
;
5271 switch_to_thread (child
);
5273 switch_to_thread (parent
);
5275 ecs
->event_thread
= inferior_thread ();
5276 ecs
->ptid
= inferior_ptid
;
5284 process_event_stop_test (ecs
);
5287 case TARGET_WAITKIND_VFORK_DONE
:
5288 /* Done with the shared memory region. Re-insert breakpoints in
5289 the parent, and keep going. */
5292 fprintf_unfiltered (gdb_stdlog
,
5293 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5295 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5296 context_switch (ecs
->ptid
);
5298 current_inferior ()->waiting_for_vfork_done
= 0;
5299 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5301 if (handle_stop_requested (ecs
))
5304 /* This also takes care of reinserting breakpoints in the
5305 previously locked inferior. */
5309 case TARGET_WAITKIND_EXECD
:
5311 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5313 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5314 context_switch (ecs
->ptid
);
5316 /* Do whatever is necessary to the parent branch of the vfork. */
5317 handle_vfork_child_exec_or_exit (1);
5319 /* This causes the eventpoints and symbol table to be reset.
5320 Must do this now, before trying to determine whether to
5322 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5324 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5326 /* In follow_exec we may have deleted the original thread and
5327 created a new one. Make sure that the event thread is the
5328 execd thread for that case (this is a nop otherwise). */
5329 ecs
->event_thread
= inferior_thread ();
5331 ecs
->event_thread
->control
.stop_bpstat
5332 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5333 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5335 /* Note that this may be referenced from inside
5336 bpstat_stop_status above, through inferior_has_execd. */
5337 xfree (ecs
->ws
.value
.execd_pathname
);
5338 ecs
->ws
.value
.execd_pathname
= NULL
;
5340 if (handle_stop_requested (ecs
))
5343 /* If no catchpoint triggered for this, then keep going. */
5344 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5346 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5350 process_event_stop_test (ecs
);
5353 /* Be careful not to try to gather much state about a thread
5354 that's in a syscall. It's frequently a losing proposition. */
5355 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5357 fprintf_unfiltered (gdb_stdlog
,
5358 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5359 /* Getting the current syscall number. */
5360 if (handle_syscall_event (ecs
) == 0)
5361 process_event_stop_test (ecs
);
5364 /* Before examining the threads further, step this thread to
5365 get it entirely out of the syscall. (We get notice of the
5366 event when the thread is just on the verge of exiting a
5367 syscall. Stepping one instruction seems to get it back
5369 case TARGET_WAITKIND_SYSCALL_RETURN
:
5371 fprintf_unfiltered (gdb_stdlog
,
5372 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5373 if (handle_syscall_event (ecs
) == 0)
5374 process_event_stop_test (ecs
);
5377 case TARGET_WAITKIND_STOPPED
:
5379 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5380 handle_signal_stop (ecs
);
5383 case TARGET_WAITKIND_NO_HISTORY
:
5385 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5386 /* Reverse execution: target ran out of history info. */
5388 /* Switch to the stopped thread. */
5389 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5390 context_switch (ecs
->ptid
);
5392 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5394 delete_just_stopped_threads_single_step_breakpoints ();
5395 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5397 if (handle_stop_requested (ecs
))
5400 observer_notify_no_history ();
5406 /* A wrapper around handle_inferior_event_1, which also makes sure
5407 that all temporary struct value objects that were created during
5408 the handling of the event get deleted at the end. */
5411 handle_inferior_event (struct execution_control_state
*ecs
)
5413 struct value
*mark
= value_mark ();
5415 handle_inferior_event_1 (ecs
);
5416 /* Purge all temporary values created during the event handling,
5417 as it could be a long time before we return to the command level
5418 where such values would otherwise be purged. */
5419 value_free_to_mark (mark
);
5422 /* Restart threads back to what they were trying to do back when we
5423 paused them for an in-line step-over. The EVENT_THREAD thread is
5427 restart_threads (struct thread_info
*event_thread
)
5429 struct thread_info
*tp
;
5431 /* In case the instruction just stepped spawned a new thread. */
5432 update_thread_list ();
5434 ALL_NON_EXITED_THREADS (tp
)
5436 if (tp
== event_thread
)
5439 fprintf_unfiltered (gdb_stdlog
,
5440 "infrun: restart threads: "
5441 "[%s] is event thread\n",
5442 target_pid_to_str (tp
->ptid
));
5446 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5449 fprintf_unfiltered (gdb_stdlog
,
5450 "infrun: restart threads: "
5451 "[%s] not meant to be running\n",
5452 target_pid_to_str (tp
->ptid
));
5459 fprintf_unfiltered (gdb_stdlog
,
5460 "infrun: restart threads: [%s] resumed\n",
5461 target_pid_to_str (tp
->ptid
));
5462 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5466 if (thread_is_in_step_over_chain (tp
))
5469 fprintf_unfiltered (gdb_stdlog
,
5470 "infrun: restart threads: "
5471 "[%s] needs step-over\n",
5472 target_pid_to_str (tp
->ptid
));
5473 gdb_assert (!tp
->resumed
);
5478 if (tp
->suspend
.waitstatus_pending_p
)
5481 fprintf_unfiltered (gdb_stdlog
,
5482 "infrun: restart threads: "
5483 "[%s] has pending status\n",
5484 target_pid_to_str (tp
->ptid
));
5489 gdb_assert (!tp
->stop_requested
);
5491 /* If some thread needs to start a step-over at this point, it
5492 should still be in the step-over queue, and thus skipped
5494 if (thread_still_needs_step_over (tp
))
5496 internal_error (__FILE__
, __LINE__
,
5497 "thread [%s] needs a step-over, but not in "
5498 "step-over queue\n",
5499 target_pid_to_str (tp
->ptid
));
5502 if (currently_stepping (tp
))
5505 fprintf_unfiltered (gdb_stdlog
,
5506 "infrun: restart threads: [%s] was stepping\n",
5507 target_pid_to_str (tp
->ptid
));
5508 keep_going_stepped_thread (tp
);
5512 struct execution_control_state ecss
;
5513 struct execution_control_state
*ecs
= &ecss
;
5516 fprintf_unfiltered (gdb_stdlog
,
5517 "infrun: restart threads: [%s] continuing\n",
5518 target_pid_to_str (tp
->ptid
));
5519 reset_ecs (ecs
, tp
);
5520 switch_to_thread (tp
->ptid
);
5521 keep_going_pass_signal (ecs
);
5526 /* Callback for iterate_over_threads. Find a resumed thread that has
5527 a pending waitstatus. */
5530 resumed_thread_with_pending_status (struct thread_info
*tp
,
5534 && tp
->suspend
.waitstatus_pending_p
);
5537 /* Called when we get an event that may finish an in-line or
5538 out-of-line (displaced stepping) step-over started previously.
5539 Return true if the event is processed and we should go back to the
5540 event loop; false if the caller should continue processing the
5544 finish_step_over (struct execution_control_state
*ecs
)
5546 int had_step_over_info
;
5548 displaced_step_fixup (ecs
->ptid
,
5549 ecs
->event_thread
->suspend
.stop_signal
);
5551 had_step_over_info
= step_over_info_valid_p ();
5553 if (had_step_over_info
)
5555 /* If we're stepping over a breakpoint with all threads locked,
5556 then only the thread that was stepped should be reporting
5558 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5560 clear_step_over_info ();
5563 if (!target_is_non_stop_p ())
5566 /* Start a new step-over in another thread if there's one that
5570 /* If we were stepping over a breakpoint before, and haven't started
5571 a new in-line step-over sequence, then restart all other threads
5572 (except the event thread). We can't do this in all-stop, as then
5573 e.g., we wouldn't be able to issue any other remote packet until
5574 these other threads stop. */
5575 if (had_step_over_info
&& !step_over_info_valid_p ())
5577 struct thread_info
*pending
;
5579 /* If we only have threads with pending statuses, the restart
5580 below won't restart any thread and so nothing re-inserts the
5581 breakpoint we just stepped over. But we need it inserted
5582 when we later process the pending events, otherwise if
5583 another thread has a pending event for this breakpoint too,
5584 we'd discard its event (because the breakpoint that
5585 originally caused the event was no longer inserted). */
5586 context_switch (ecs
->ptid
);
5587 insert_breakpoints ();
5589 restart_threads (ecs
->event_thread
);
5591 /* If we have events pending, go through handle_inferior_event
5592 again, picking up a pending event at random. This avoids
5593 thread starvation. */
5595 /* But not if we just stepped over a watchpoint in order to let
5596 the instruction execute so we can evaluate its expression.
5597 The set of watchpoints that triggered is recorded in the
5598 breakpoint objects themselves (see bp->watchpoint_triggered).
5599 If we processed another event first, that other event could
5600 clobber this info. */
5601 if (ecs
->event_thread
->stepping_over_watchpoint
)
5604 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5606 if (pending
!= NULL
)
5608 struct thread_info
*tp
= ecs
->event_thread
;
5609 struct regcache
*regcache
;
5613 fprintf_unfiltered (gdb_stdlog
,
5614 "infrun: found resumed threads with "
5615 "pending events, saving status\n");
5618 gdb_assert (pending
!= tp
);
5620 /* Record the event thread's event for later. */
5621 save_waitstatus (tp
, &ecs
->ws
);
5622 /* This was cleared early, by handle_inferior_event. Set it
5623 so this pending event is considered by
5627 gdb_assert (!tp
->executing
);
5629 regcache
= get_thread_regcache (tp
->ptid
);
5630 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5634 fprintf_unfiltered (gdb_stdlog
,
5635 "infrun: saved stop_pc=%s for %s "
5636 "(currently_stepping=%d)\n",
5637 paddress (target_gdbarch (),
5638 tp
->suspend
.stop_pc
),
5639 target_pid_to_str (tp
->ptid
),
5640 currently_stepping (tp
));
5643 /* This in-line step-over finished; clear this so we won't
5644 start a new one. This is what handle_signal_stop would
5645 do, if we returned false. */
5646 tp
->stepping_over_breakpoint
= 0;
5648 /* Wake up the event loop again. */
5649 mark_async_event_handler (infrun_async_inferior_event_token
);
5651 prepare_to_wait (ecs
);
5659 /* Come here when the program has stopped with a signal. */
5662 handle_signal_stop (struct execution_control_state
*ecs
)
5664 struct frame_info
*frame
;
5665 struct gdbarch
*gdbarch
;
5666 int stopped_by_watchpoint
;
5667 enum stop_kind stop_soon
;
5670 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5672 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5674 /* Do we need to clean up the state of a thread that has
5675 completed a displaced single-step? (Doing so usually affects
5676 the PC, so do it here, before we set stop_pc.) */
5677 if (finish_step_over (ecs
))
5680 /* If we either finished a single-step or hit a breakpoint, but
5681 the user wanted this thread to be stopped, pretend we got a
5682 SIG0 (generic unsignaled stop). */
5683 if (ecs
->event_thread
->stop_requested
5684 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5685 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5687 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5691 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5692 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5693 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
5695 inferior_ptid
= ecs
->ptid
;
5697 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5698 paddress (gdbarch
, stop_pc
));
5699 if (target_stopped_by_watchpoint ())
5703 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5705 if (target_stopped_data_address (¤t_target
, &addr
))
5706 fprintf_unfiltered (gdb_stdlog
,
5707 "infrun: stopped data address = %s\n",
5708 paddress (gdbarch
, addr
));
5710 fprintf_unfiltered (gdb_stdlog
,
5711 "infrun: (no data address available)\n");
5715 /* This is originated from start_remote(), start_inferior() and
5716 shared libraries hook functions. */
5717 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5718 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5720 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5721 context_switch (ecs
->ptid
);
5723 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5724 stop_print_frame
= 1;
5729 /* This originates from attach_command(). We need to overwrite
5730 the stop_signal here, because some kernels don't ignore a
5731 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5732 See more comments in inferior.h. On the other hand, if we
5733 get a non-SIGSTOP, report it to the user - assume the backend
5734 will handle the SIGSTOP if it should show up later.
5736 Also consider that the attach is complete when we see a
5737 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5738 target extended-remote report it instead of a SIGSTOP
5739 (e.g. gdbserver). We already rely on SIGTRAP being our
5740 signal, so this is no exception.
5742 Also consider that the attach is complete when we see a
5743 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5744 the target to stop all threads of the inferior, in case the
5745 low level attach operation doesn't stop them implicitly. If
5746 they weren't stopped implicitly, then the stub will report a
5747 GDB_SIGNAL_0, meaning: stopped for no particular reason
5748 other than GDB's request. */
5749 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5750 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5751 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5752 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5754 stop_print_frame
= 1;
5756 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5760 /* See if something interesting happened to the non-current thread. If
5761 so, then switch to that thread. */
5762 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5765 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5767 context_switch (ecs
->ptid
);
5769 if (deprecated_context_hook
)
5770 deprecated_context_hook (ptid_to_global_thread_id (ecs
->ptid
));
5773 /* At this point, get hold of the now-current thread's frame. */
5774 frame
= get_current_frame ();
5775 gdbarch
= get_frame_arch (frame
);
5777 /* Pull the single step breakpoints out of the target. */
5778 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5780 struct regcache
*regcache
;
5781 struct address_space
*aspace
;
5784 regcache
= get_thread_regcache (ecs
->ptid
);
5785 aspace
= get_regcache_aspace (regcache
);
5786 pc
= regcache_read_pc (regcache
);
5788 /* However, before doing so, if this single-step breakpoint was
5789 actually for another thread, set this thread up for moving
5791 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5794 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5798 fprintf_unfiltered (gdb_stdlog
,
5799 "infrun: [%s] hit another thread's "
5800 "single-step breakpoint\n",
5801 target_pid_to_str (ecs
->ptid
));
5803 ecs
->hit_singlestep_breakpoint
= 1;
5810 fprintf_unfiltered (gdb_stdlog
,
5811 "infrun: [%s] hit its "
5812 "single-step breakpoint\n",
5813 target_pid_to_str (ecs
->ptid
));
5817 delete_just_stopped_threads_single_step_breakpoints ();
5819 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5820 && ecs
->event_thread
->control
.trap_expected
5821 && ecs
->event_thread
->stepping_over_watchpoint
)
5822 stopped_by_watchpoint
= 0;
5824 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5826 /* If necessary, step over this watchpoint. We'll be back to display
5828 if (stopped_by_watchpoint
5829 && (target_have_steppable_watchpoint
5830 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5832 /* At this point, we are stopped at an instruction which has
5833 attempted to write to a piece of memory under control of
5834 a watchpoint. The instruction hasn't actually executed
5835 yet. If we were to evaluate the watchpoint expression
5836 now, we would get the old value, and therefore no change
5837 would seem to have occurred.
5839 In order to make watchpoints work `right', we really need
5840 to complete the memory write, and then evaluate the
5841 watchpoint expression. We do this by single-stepping the
5844 It may not be necessary to disable the watchpoint to step over
5845 it. For example, the PA can (with some kernel cooperation)
5846 single step over a watchpoint without disabling the watchpoint.
5848 It is far more common to need to disable a watchpoint to step
5849 the inferior over it. If we have non-steppable watchpoints,
5850 we must disable the current watchpoint; it's simplest to
5851 disable all watchpoints.
5853 Any breakpoint at PC must also be stepped over -- if there's
5854 one, it will have already triggered before the watchpoint
5855 triggered, and we either already reported it to the user, or
5856 it didn't cause a stop and we called keep_going. In either
5857 case, if there was a breakpoint at PC, we must be trying to
5859 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5864 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5865 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5866 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5867 ecs
->event_thread
->control
.stop_step
= 0;
5868 stop_print_frame
= 1;
5869 stopped_by_random_signal
= 0;
5871 /* Hide inlined functions starting here, unless we just performed stepi or
5872 nexti. After stepi and nexti, always show the innermost frame (not any
5873 inline function call sites). */
5874 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5876 struct address_space
*aspace
=
5877 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5879 /* skip_inline_frames is expensive, so we avoid it if we can
5880 determine that the address is one where functions cannot have
5881 been inlined. This improves performance with inferiors that
5882 load a lot of shared libraries, because the solib event
5883 breakpoint is defined as the address of a function (i.e. not
5884 inline). Note that we have to check the previous PC as well
5885 as the current one to catch cases when we have just
5886 single-stepped off a breakpoint prior to reinstating it.
5887 Note that we're assuming that the code we single-step to is
5888 not inline, but that's not definitive: there's nothing
5889 preventing the event breakpoint function from containing
5890 inlined code, and the single-step ending up there. If the
5891 user had set a breakpoint on that inlined code, the missing
5892 skip_inline_frames call would break things. Fortunately
5893 that's an extremely unlikely scenario. */
5894 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5895 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5896 && ecs
->event_thread
->control
.trap_expected
5897 && pc_at_non_inline_function (aspace
,
5898 ecs
->event_thread
->prev_pc
,
5901 skip_inline_frames (ecs
->ptid
);
5903 /* Re-fetch current thread's frame in case that invalidated
5905 frame
= get_current_frame ();
5906 gdbarch
= get_frame_arch (frame
);
5910 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5911 && ecs
->event_thread
->control
.trap_expected
5912 && gdbarch_single_step_through_delay_p (gdbarch
)
5913 && currently_stepping (ecs
->event_thread
))
5915 /* We're trying to step off a breakpoint. Turns out that we're
5916 also on an instruction that needs to be stepped multiple
5917 times before it's been fully executing. E.g., architectures
5918 with a delay slot. It needs to be stepped twice, once for
5919 the instruction and once for the delay slot. */
5920 int step_through_delay
5921 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5923 if (debug_infrun
&& step_through_delay
)
5924 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5925 if (ecs
->event_thread
->control
.step_range_end
== 0
5926 && step_through_delay
)
5928 /* The user issued a continue when stopped at a breakpoint.
5929 Set up for another trap and get out of here. */
5930 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5934 else if (step_through_delay
)
5936 /* The user issued a step when stopped at a breakpoint.
5937 Maybe we should stop, maybe we should not - the delay
5938 slot *might* correspond to a line of source. In any
5939 case, don't decide that here, just set
5940 ecs->stepping_over_breakpoint, making sure we
5941 single-step again before breakpoints are re-inserted. */
5942 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5946 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5947 handles this event. */
5948 ecs
->event_thread
->control
.stop_bpstat
5949 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5950 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5952 /* Following in case break condition called a
5954 stop_print_frame
= 1;
5956 /* This is where we handle "moribund" watchpoints. Unlike
5957 software breakpoints traps, hardware watchpoint traps are
5958 always distinguishable from random traps. If no high-level
5959 watchpoint is associated with the reported stop data address
5960 anymore, then the bpstat does not explain the signal ---
5961 simply make sure to ignore it if `stopped_by_watchpoint' is
5965 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5966 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5968 && stopped_by_watchpoint
)
5969 fprintf_unfiltered (gdb_stdlog
,
5970 "infrun: no user watchpoint explains "
5971 "watchpoint SIGTRAP, ignoring\n");
5973 /* NOTE: cagney/2003-03-29: These checks for a random signal
5974 at one stage in the past included checks for an inferior
5975 function call's call dummy's return breakpoint. The original
5976 comment, that went with the test, read:
5978 ``End of a stack dummy. Some systems (e.g. Sony news) give
5979 another signal besides SIGTRAP, so check here as well as
5982 If someone ever tries to get call dummys on a
5983 non-executable stack to work (where the target would stop
5984 with something like a SIGSEGV), then those tests might need
5985 to be re-instated. Given, however, that the tests were only
5986 enabled when momentary breakpoints were not being used, I
5987 suspect that it won't be the case.
5989 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5990 be necessary for call dummies on a non-executable stack on
5993 /* See if the breakpoints module can explain the signal. */
5995 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5996 ecs
->event_thread
->suspend
.stop_signal
);
5998 /* Maybe this was a trap for a software breakpoint that has since
6000 if (random_signal
&& target_stopped_by_sw_breakpoint ())
6002 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
6004 struct regcache
*regcache
;
6007 /* Re-adjust PC to what the program would see if GDB was not
6009 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
6010 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6013 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
6015 if (record_full_is_used ())
6016 record_full_gdb_operation_disable_set ();
6018 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
6020 do_cleanups (old_cleanups
);
6025 /* A delayed software breakpoint event. Ignore the trap. */
6027 fprintf_unfiltered (gdb_stdlog
,
6028 "infrun: delayed software breakpoint "
6029 "trap, ignoring\n");
6034 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6035 has since been removed. */
6036 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6038 /* A delayed hardware breakpoint event. Ignore the trap. */
6040 fprintf_unfiltered (gdb_stdlog
,
6041 "infrun: delayed hardware breakpoint/watchpoint "
6042 "trap, ignoring\n");
6046 /* If not, perhaps stepping/nexting can. */
6048 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6049 && currently_stepping (ecs
->event_thread
));
6051 /* Perhaps the thread hit a single-step breakpoint of _another_
6052 thread. Single-step breakpoints are transparent to the
6053 breakpoints module. */
6055 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6057 /* No? Perhaps we got a moribund watchpoint. */
6059 random_signal
= !stopped_by_watchpoint
;
6061 /* Always stop if the user explicitly requested this thread to
6063 if (ecs
->event_thread
->stop_requested
)
6067 fprintf_unfiltered (gdb_stdlog
, "infrun: user-requested stop\n");
6070 /* For the program's own signals, act according to
6071 the signal handling tables. */
6075 /* Signal not for debugging purposes. */
6076 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
6077 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6080 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
6081 gdb_signal_to_symbol_string (stop_signal
));
6083 stopped_by_random_signal
= 1;
6085 /* Always stop on signals if we're either just gaining control
6086 of the program, or the user explicitly requested this thread
6087 to remain stopped. */
6088 if (stop_soon
!= NO_STOP_QUIETLY
6089 || ecs
->event_thread
->stop_requested
6091 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
6097 /* Notify observers the signal has "handle print" set. Note we
6098 returned early above if stopping; normal_stop handles the
6099 printing in that case. */
6100 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6102 /* The signal table tells us to print about this signal. */
6103 target_terminal_ours_for_output ();
6104 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
6105 target_terminal_inferior ();
6108 /* Clear the signal if it should not be passed. */
6109 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6110 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6112 if (ecs
->event_thread
->prev_pc
== stop_pc
6113 && ecs
->event_thread
->control
.trap_expected
6114 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6116 /* We were just starting a new sequence, attempting to
6117 single-step off of a breakpoint and expecting a SIGTRAP.
6118 Instead this signal arrives. This signal will take us out
6119 of the stepping range so GDB needs to remember to, when
6120 the signal handler returns, resume stepping off that
6122 /* To simplify things, "continue" is forced to use the same
6123 code paths as single-step - set a breakpoint at the
6124 signal return address and then, once hit, step off that
6127 fprintf_unfiltered (gdb_stdlog
,
6128 "infrun: signal arrived while stepping over "
6131 insert_hp_step_resume_breakpoint_at_frame (frame
);
6132 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6133 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6134 ecs
->event_thread
->control
.trap_expected
= 0;
6136 /* If we were nexting/stepping some other thread, switch to
6137 it, so that we don't continue it, losing control. */
6138 if (!switch_back_to_stepped_thread (ecs
))
6143 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6144 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6145 || ecs
->event_thread
->control
.step_range_end
== 1)
6146 && frame_id_eq (get_stack_frame_id (frame
),
6147 ecs
->event_thread
->control
.step_stack_frame_id
)
6148 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6150 /* The inferior is about to take a signal that will take it
6151 out of the single step range. Set a breakpoint at the
6152 current PC (which is presumably where the signal handler
6153 will eventually return) and then allow the inferior to
6156 Note that this is only needed for a signal delivered
6157 while in the single-step range. Nested signals aren't a
6158 problem as they eventually all return. */
6160 fprintf_unfiltered (gdb_stdlog
,
6161 "infrun: signal may take us out of "
6162 "single-step range\n");
6164 clear_step_over_info ();
6165 insert_hp_step_resume_breakpoint_at_frame (frame
);
6166 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6167 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6168 ecs
->event_thread
->control
.trap_expected
= 0;
6173 /* Note: step_resume_breakpoint may be non-NULL. This occures
6174 when either there's a nested signal, or when there's a
6175 pending signal enabled just as the signal handler returns
6176 (leaving the inferior at the step-resume-breakpoint without
6177 actually executing it). Either way continue until the
6178 breakpoint is really hit. */
6180 if (!switch_back_to_stepped_thread (ecs
))
6183 fprintf_unfiltered (gdb_stdlog
,
6184 "infrun: random signal, keep going\n");
6191 process_event_stop_test (ecs
);
6194 /* Come here when we've got some debug event / signal we can explain
6195 (IOW, not a random signal), and test whether it should cause a
6196 stop, or whether we should resume the inferior (transparently).
6197 E.g., could be a breakpoint whose condition evaluates false; we
6198 could be still stepping within the line; etc. */
6201 process_event_stop_test (struct execution_control_state
*ecs
)
6203 struct symtab_and_line stop_pc_sal
;
6204 struct frame_info
*frame
;
6205 struct gdbarch
*gdbarch
;
6206 CORE_ADDR jmp_buf_pc
;
6207 struct bpstat_what what
;
6209 /* Handle cases caused by hitting a breakpoint. */
6211 frame
= get_current_frame ();
6212 gdbarch
= get_frame_arch (frame
);
6214 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6216 if (what
.call_dummy
)
6218 stop_stack_dummy
= what
.call_dummy
;
6221 /* A few breakpoint types have callbacks associated (e.g.,
6222 bp_jit_event). Run them now. */
6223 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6225 /* If we hit an internal event that triggers symbol changes, the
6226 current frame will be invalidated within bpstat_what (e.g., if we
6227 hit an internal solib event). Re-fetch it. */
6228 frame
= get_current_frame ();
6229 gdbarch
= get_frame_arch (frame
);
6231 switch (what
.main_action
)
6233 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6234 /* If we hit the breakpoint at longjmp while stepping, we
6235 install a momentary breakpoint at the target of the
6239 fprintf_unfiltered (gdb_stdlog
,
6240 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6242 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6244 if (what
.is_longjmp
)
6246 struct value
*arg_value
;
6248 /* If we set the longjmp breakpoint via a SystemTap probe,
6249 then use it to extract the arguments. The destination PC
6250 is the third argument to the probe. */
6251 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6254 jmp_buf_pc
= value_as_address (arg_value
);
6255 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6257 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6258 || !gdbarch_get_longjmp_target (gdbarch
,
6259 frame
, &jmp_buf_pc
))
6262 fprintf_unfiltered (gdb_stdlog
,
6263 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6264 "(!gdbarch_get_longjmp_target)\n");
6269 /* Insert a breakpoint at resume address. */
6270 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6273 check_exception_resume (ecs
, frame
);
6277 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6279 struct frame_info
*init_frame
;
6281 /* There are several cases to consider.
6283 1. The initiating frame no longer exists. In this case we
6284 must stop, because the exception or longjmp has gone too
6287 2. The initiating frame exists, and is the same as the
6288 current frame. We stop, because the exception or longjmp
6291 3. The initiating frame exists and is different from the
6292 current frame. This means the exception or longjmp has
6293 been caught beneath the initiating frame, so keep going.
6295 4. longjmp breakpoint has been placed just to protect
6296 against stale dummy frames and user is not interested in
6297 stopping around longjmps. */
6300 fprintf_unfiltered (gdb_stdlog
,
6301 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6303 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6305 delete_exception_resume_breakpoint (ecs
->event_thread
);
6307 if (what
.is_longjmp
)
6309 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6311 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6319 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6323 struct frame_id current_id
6324 = get_frame_id (get_current_frame ());
6325 if (frame_id_eq (current_id
,
6326 ecs
->event_thread
->initiating_frame
))
6328 /* Case 2. Fall through. */
6338 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6340 delete_step_resume_breakpoint (ecs
->event_thread
);
6342 end_stepping_range (ecs
);
6346 case BPSTAT_WHAT_SINGLE
:
6348 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6349 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6350 /* Still need to check other stuff, at least the case where we
6351 are stepping and step out of the right range. */
6354 case BPSTAT_WHAT_STEP_RESUME
:
6356 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6358 delete_step_resume_breakpoint (ecs
->event_thread
);
6359 if (ecs
->event_thread
->control
.proceed_to_finish
6360 && execution_direction
== EXEC_REVERSE
)
6362 struct thread_info
*tp
= ecs
->event_thread
;
6364 /* We are finishing a function in reverse, and just hit the
6365 step-resume breakpoint at the start address of the
6366 function, and we're almost there -- just need to back up
6367 by one more single-step, which should take us back to the
6369 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6373 fill_in_stop_func (gdbarch
, ecs
);
6374 if (stop_pc
== ecs
->stop_func_start
6375 && execution_direction
== EXEC_REVERSE
)
6377 /* We are stepping over a function call in reverse, and just
6378 hit the step-resume breakpoint at the start address of
6379 the function. Go back to single-stepping, which should
6380 take us back to the function call. */
6381 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6387 case BPSTAT_WHAT_STOP_NOISY
:
6389 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6390 stop_print_frame
= 1;
6392 /* Assume the thread stopped for a breapoint. We'll still check
6393 whether a/the breakpoint is there when the thread is next
6395 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6400 case BPSTAT_WHAT_STOP_SILENT
:
6402 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6403 stop_print_frame
= 0;
6405 /* Assume the thread stopped for a breapoint. We'll still check
6406 whether a/the breakpoint is there when the thread is next
6408 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6412 case BPSTAT_WHAT_HP_STEP_RESUME
:
6414 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6416 delete_step_resume_breakpoint (ecs
->event_thread
);
6417 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6419 /* Back when the step-resume breakpoint was inserted, we
6420 were trying to single-step off a breakpoint. Go back to
6422 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6423 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6429 case BPSTAT_WHAT_KEEP_CHECKING
:
6433 /* If we stepped a permanent breakpoint and we had a high priority
6434 step-resume breakpoint for the address we stepped, but we didn't
6435 hit it, then we must have stepped into the signal handler. The
6436 step-resume was only necessary to catch the case of _not_
6437 stepping into the handler, so delete it, and fall through to
6438 checking whether the step finished. */
6439 if (ecs
->event_thread
->stepped_breakpoint
)
6441 struct breakpoint
*sr_bp
6442 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6445 && sr_bp
->loc
->permanent
6446 && sr_bp
->type
== bp_hp_step_resume
6447 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6450 fprintf_unfiltered (gdb_stdlog
,
6451 "infrun: stepped permanent breakpoint, stopped in "
6453 delete_step_resume_breakpoint (ecs
->event_thread
);
6454 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6458 /* We come here if we hit a breakpoint but should not stop for it.
6459 Possibly we also were stepping and should stop for that. So fall
6460 through and test for stepping. But, if not stepping, do not
6463 /* In all-stop mode, if we're currently stepping but have stopped in
6464 some other thread, we need to switch back to the stepped thread. */
6465 if (switch_back_to_stepped_thread (ecs
))
6468 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6471 fprintf_unfiltered (gdb_stdlog
,
6472 "infrun: step-resume breakpoint is inserted\n");
6474 /* Having a step-resume breakpoint overrides anything
6475 else having to do with stepping commands until
6476 that breakpoint is reached. */
6481 if (ecs
->event_thread
->control
.step_range_end
== 0)
6484 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6485 /* Likewise if we aren't even stepping. */
6490 /* Re-fetch current thread's frame in case the code above caused
6491 the frame cache to be re-initialized, making our FRAME variable
6492 a dangling pointer. */
6493 frame
= get_current_frame ();
6494 gdbarch
= get_frame_arch (frame
);
6495 fill_in_stop_func (gdbarch
, ecs
);
6497 /* If stepping through a line, keep going if still within it.
6499 Note that step_range_end is the address of the first instruction
6500 beyond the step range, and NOT the address of the last instruction
6503 Note also that during reverse execution, we may be stepping
6504 through a function epilogue and therefore must detect when
6505 the current-frame changes in the middle of a line. */
6507 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6508 && (execution_direction
!= EXEC_REVERSE
6509 || frame_id_eq (get_frame_id (frame
),
6510 ecs
->event_thread
->control
.step_frame_id
)))
6514 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6515 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6516 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6518 /* Tentatively re-enable range stepping; `resume' disables it if
6519 necessary (e.g., if we're stepping over a breakpoint or we
6520 have software watchpoints). */
6521 ecs
->event_thread
->control
.may_range_step
= 1;
6523 /* When stepping backward, stop at beginning of line range
6524 (unless it's the function entry point, in which case
6525 keep going back to the call point). */
6526 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6527 && stop_pc
!= ecs
->stop_func_start
6528 && execution_direction
== EXEC_REVERSE
)
6529 end_stepping_range (ecs
);
6536 /* We stepped out of the stepping range. */
6538 /* If we are stepping at the source level and entered the runtime
6539 loader dynamic symbol resolution code...
6541 EXEC_FORWARD: we keep on single stepping until we exit the run
6542 time loader code and reach the callee's address.
6544 EXEC_REVERSE: we've already executed the callee (backward), and
6545 the runtime loader code is handled just like any other
6546 undebuggable function call. Now we need only keep stepping
6547 backward through the trampoline code, and that's handled further
6548 down, so there is nothing for us to do here. */
6550 if (execution_direction
!= EXEC_REVERSE
6551 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6552 && in_solib_dynsym_resolve_code (stop_pc
))
6554 CORE_ADDR pc_after_resolver
=
6555 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6558 fprintf_unfiltered (gdb_stdlog
,
6559 "infrun: stepped into dynsym resolve code\n");
6561 if (pc_after_resolver
)
6563 /* Set up a step-resume breakpoint at the address
6564 indicated by SKIP_SOLIB_RESOLVER. */
6565 symtab_and_line sr_sal
;
6566 sr_sal
.pc
= pc_after_resolver
;
6567 sr_sal
.pspace
= get_frame_program_space (frame
);
6569 insert_step_resume_breakpoint_at_sal (gdbarch
,
6570 sr_sal
, null_frame_id
);
6577 if (ecs
->event_thread
->control
.step_range_end
!= 1
6578 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6579 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6580 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6583 fprintf_unfiltered (gdb_stdlog
,
6584 "infrun: stepped into signal trampoline\n");
6585 /* The inferior, while doing a "step" or "next", has ended up in
6586 a signal trampoline (either by a signal being delivered or by
6587 the signal handler returning). Just single-step until the
6588 inferior leaves the trampoline (either by calling the handler
6594 /* If we're in the return path from a shared library trampoline,
6595 we want to proceed through the trampoline when stepping. */
6596 /* macro/2012-04-25: This needs to come before the subroutine
6597 call check below as on some targets return trampolines look
6598 like subroutine calls (MIPS16 return thunks). */
6599 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6600 stop_pc
, ecs
->stop_func_name
)
6601 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6603 /* Determine where this trampoline returns. */
6604 CORE_ADDR real_stop_pc
;
6606 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6609 fprintf_unfiltered (gdb_stdlog
,
6610 "infrun: stepped into solib return tramp\n");
6612 /* Only proceed through if we know where it's going. */
6615 /* And put the step-breakpoint there and go until there. */
6616 symtab_and_line sr_sal
;
6617 sr_sal
.pc
= real_stop_pc
;
6618 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6619 sr_sal
.pspace
= get_frame_program_space (frame
);
6621 /* Do not specify what the fp should be when we stop since
6622 on some machines the prologue is where the new fp value
6624 insert_step_resume_breakpoint_at_sal (gdbarch
,
6625 sr_sal
, null_frame_id
);
6627 /* Restart without fiddling with the step ranges or
6634 /* Check for subroutine calls. The check for the current frame
6635 equalling the step ID is not necessary - the check of the
6636 previous frame's ID is sufficient - but it is a common case and
6637 cheaper than checking the previous frame's ID.
6639 NOTE: frame_id_eq will never report two invalid frame IDs as
6640 being equal, so to get into this block, both the current and
6641 previous frame must have valid frame IDs. */
6642 /* The outer_frame_id check is a heuristic to detect stepping
6643 through startup code. If we step over an instruction which
6644 sets the stack pointer from an invalid value to a valid value,
6645 we may detect that as a subroutine call from the mythical
6646 "outermost" function. This could be fixed by marking
6647 outermost frames as !stack_p,code_p,special_p. Then the
6648 initial outermost frame, before sp was valid, would
6649 have code_addr == &_start. See the comment in frame_id_eq
6651 if (!frame_id_eq (get_stack_frame_id (frame
),
6652 ecs
->event_thread
->control
.step_stack_frame_id
)
6653 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6654 ecs
->event_thread
->control
.step_stack_frame_id
)
6655 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6657 || (ecs
->event_thread
->control
.step_start_function
6658 != find_pc_function (stop_pc
)))))
6660 CORE_ADDR real_stop_pc
;
6663 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6665 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6667 /* I presume that step_over_calls is only 0 when we're
6668 supposed to be stepping at the assembly language level
6669 ("stepi"). Just stop. */
6670 /* And this works the same backward as frontward. MVS */
6671 end_stepping_range (ecs
);
6675 /* Reverse stepping through solib trampolines. */
6677 if (execution_direction
== EXEC_REVERSE
6678 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6679 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6680 || (ecs
->stop_func_start
== 0
6681 && in_solib_dynsym_resolve_code (stop_pc
))))
6683 /* Any solib trampoline code can be handled in reverse
6684 by simply continuing to single-step. We have already
6685 executed the solib function (backwards), and a few
6686 steps will take us back through the trampoline to the
6692 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6694 /* We're doing a "next".
6696 Normal (forward) execution: set a breakpoint at the
6697 callee's return address (the address at which the caller
6700 Reverse (backward) execution. set the step-resume
6701 breakpoint at the start of the function that we just
6702 stepped into (backwards), and continue to there. When we
6703 get there, we'll need to single-step back to the caller. */
6705 if (execution_direction
== EXEC_REVERSE
)
6707 /* If we're already at the start of the function, we've either
6708 just stepped backward into a single instruction function,
6709 or stepped back out of a signal handler to the first instruction
6710 of the function. Just keep going, which will single-step back
6712 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6714 /* Normal function call return (static or dynamic). */
6715 symtab_and_line sr_sal
;
6716 sr_sal
.pc
= ecs
->stop_func_start
;
6717 sr_sal
.pspace
= get_frame_program_space (frame
);
6718 insert_step_resume_breakpoint_at_sal (gdbarch
,
6719 sr_sal
, null_frame_id
);
6723 insert_step_resume_breakpoint_at_caller (frame
);
6729 /* If we are in a function call trampoline (a stub between the
6730 calling routine and the real function), locate the real
6731 function. That's what tells us (a) whether we want to step
6732 into it at all, and (b) what prologue we want to run to the
6733 end of, if we do step into it. */
6734 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6735 if (real_stop_pc
== 0)
6736 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6737 if (real_stop_pc
!= 0)
6738 ecs
->stop_func_start
= real_stop_pc
;
6740 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6742 symtab_and_line sr_sal
;
6743 sr_sal
.pc
= ecs
->stop_func_start
;
6744 sr_sal
.pspace
= get_frame_program_space (frame
);
6746 insert_step_resume_breakpoint_at_sal (gdbarch
,
6747 sr_sal
, null_frame_id
);
6752 /* If we have line number information for the function we are
6753 thinking of stepping into and the function isn't on the skip
6756 If there are several symtabs at that PC (e.g. with include
6757 files), just want to know whether *any* of them have line
6758 numbers. find_pc_line handles this. */
6760 struct symtab_and_line tmp_sal
;
6762 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6763 if (tmp_sal
.line
!= 0
6764 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6767 if (execution_direction
== EXEC_REVERSE
)
6768 handle_step_into_function_backward (gdbarch
, ecs
);
6770 handle_step_into_function (gdbarch
, ecs
);
6775 /* If we have no line number and the step-stop-if-no-debug is
6776 set, we stop the step so that the user has a chance to switch
6777 in assembly mode. */
6778 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6779 && step_stop_if_no_debug
)
6781 end_stepping_range (ecs
);
6785 if (execution_direction
== EXEC_REVERSE
)
6787 /* If we're already at the start of the function, we've either just
6788 stepped backward into a single instruction function without line
6789 number info, or stepped back out of a signal handler to the first
6790 instruction of the function without line number info. Just keep
6791 going, which will single-step back to the caller. */
6792 if (ecs
->stop_func_start
!= stop_pc
)
6794 /* Set a breakpoint at callee's start address.
6795 From there we can step once and be back in the caller. */
6796 symtab_and_line sr_sal
;
6797 sr_sal
.pc
= ecs
->stop_func_start
;
6798 sr_sal
.pspace
= get_frame_program_space (frame
);
6799 insert_step_resume_breakpoint_at_sal (gdbarch
,
6800 sr_sal
, null_frame_id
);
6804 /* Set a breakpoint at callee's return address (the address
6805 at which the caller will resume). */
6806 insert_step_resume_breakpoint_at_caller (frame
);
6812 /* Reverse stepping through solib trampolines. */
6814 if (execution_direction
== EXEC_REVERSE
6815 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6817 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6818 || (ecs
->stop_func_start
== 0
6819 && in_solib_dynsym_resolve_code (stop_pc
)))
6821 /* Any solib trampoline code can be handled in reverse
6822 by simply continuing to single-step. We have already
6823 executed the solib function (backwards), and a few
6824 steps will take us back through the trampoline to the
6829 else if (in_solib_dynsym_resolve_code (stop_pc
))
6831 /* Stepped backward into the solib dynsym resolver.
6832 Set a breakpoint at its start and continue, then
6833 one more step will take us out. */
6834 symtab_and_line sr_sal
;
6835 sr_sal
.pc
= ecs
->stop_func_start
;
6836 sr_sal
.pspace
= get_frame_program_space (frame
);
6837 insert_step_resume_breakpoint_at_sal (gdbarch
,
6838 sr_sal
, null_frame_id
);
6844 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6846 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6847 the trampoline processing logic, however, there are some trampolines
6848 that have no names, so we should do trampoline handling first. */
6849 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6850 && ecs
->stop_func_name
== NULL
6851 && stop_pc_sal
.line
== 0)
6854 fprintf_unfiltered (gdb_stdlog
,
6855 "infrun: stepped into undebuggable function\n");
6857 /* The inferior just stepped into, or returned to, an
6858 undebuggable function (where there is no debugging information
6859 and no line number corresponding to the address where the
6860 inferior stopped). Since we want to skip this kind of code,
6861 we keep going until the inferior returns from this
6862 function - unless the user has asked us not to (via
6863 set step-mode) or we no longer know how to get back
6864 to the call site. */
6865 if (step_stop_if_no_debug
6866 || !frame_id_p (frame_unwind_caller_id (frame
)))
6868 /* If we have no line number and the step-stop-if-no-debug
6869 is set, we stop the step so that the user has a chance to
6870 switch in assembly mode. */
6871 end_stepping_range (ecs
);
6876 /* Set a breakpoint at callee's return address (the address
6877 at which the caller will resume). */
6878 insert_step_resume_breakpoint_at_caller (frame
);
6884 if (ecs
->event_thread
->control
.step_range_end
== 1)
6886 /* It is stepi or nexti. We always want to stop stepping after
6889 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6890 end_stepping_range (ecs
);
6894 if (stop_pc_sal
.line
== 0)
6896 /* We have no line number information. That means to stop
6897 stepping (does this always happen right after one instruction,
6898 when we do "s" in a function with no line numbers,
6899 or can this happen as a result of a return or longjmp?). */
6901 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6902 end_stepping_range (ecs
);
6906 /* Look for "calls" to inlined functions, part one. If the inline
6907 frame machinery detected some skipped call sites, we have entered
6908 a new inline function. */
6910 if (frame_id_eq (get_frame_id (get_current_frame ()),
6911 ecs
->event_thread
->control
.step_frame_id
)
6912 && inline_skipped_frames (ecs
->ptid
))
6915 fprintf_unfiltered (gdb_stdlog
,
6916 "infrun: stepped into inlined function\n");
6918 symtab_and_line call_sal
= find_frame_sal (get_current_frame ());
6920 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6922 /* For "step", we're going to stop. But if the call site
6923 for this inlined function is on the same source line as
6924 we were previously stepping, go down into the function
6925 first. Otherwise stop at the call site. */
6927 if (call_sal
.line
== ecs
->event_thread
->current_line
6928 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6929 step_into_inline_frame (ecs
->ptid
);
6931 end_stepping_range (ecs
);
6936 /* For "next", we should stop at the call site if it is on a
6937 different source line. Otherwise continue through the
6938 inlined function. */
6939 if (call_sal
.line
== ecs
->event_thread
->current_line
6940 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6943 end_stepping_range (ecs
);
6948 /* Look for "calls" to inlined functions, part two. If we are still
6949 in the same real function we were stepping through, but we have
6950 to go further up to find the exact frame ID, we are stepping
6951 through a more inlined call beyond its call site. */
6953 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6954 && !frame_id_eq (get_frame_id (get_current_frame ()),
6955 ecs
->event_thread
->control
.step_frame_id
)
6956 && stepped_in_from (get_current_frame (),
6957 ecs
->event_thread
->control
.step_frame_id
))
6960 fprintf_unfiltered (gdb_stdlog
,
6961 "infrun: stepping through inlined function\n");
6963 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6966 end_stepping_range (ecs
);
6970 if ((stop_pc
== stop_pc_sal
.pc
)
6971 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6972 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6974 /* We are at the start of a different line. So stop. Note that
6975 we don't stop if we step into the middle of a different line.
6976 That is said to make things like for (;;) statements work
6979 fprintf_unfiltered (gdb_stdlog
,
6980 "infrun: stepped to a different line\n");
6981 end_stepping_range (ecs
);
6985 /* We aren't done stepping.
6987 Optimize by setting the stepping range to the line.
6988 (We might not be in the original line, but if we entered a
6989 new line in mid-statement, we continue stepping. This makes
6990 things like for(;;) statements work better.) */
6992 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
6993 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
6994 ecs
->event_thread
->control
.may_range_step
= 1;
6995 set_step_info (frame
, stop_pc_sal
);
6998 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
7002 /* In all-stop mode, if we're currently stepping but have stopped in
7003 some other thread, we may need to switch back to the stepped
7004 thread. Returns true we set the inferior running, false if we left
7005 it stopped (and the event needs further processing). */
7008 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7010 if (!target_is_non_stop_p ())
7012 struct thread_info
*tp
;
7013 struct thread_info
*stepping_thread
;
7015 /* If any thread is blocked on some internal breakpoint, and we
7016 simply need to step over that breakpoint to get it going
7017 again, do that first. */
7019 /* However, if we see an event for the stepping thread, then we
7020 know all other threads have been moved past their breakpoints
7021 already. Let the caller check whether the step is finished,
7022 etc., before deciding to move it past a breakpoint. */
7023 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7026 /* Check if the current thread is blocked on an incomplete
7027 step-over, interrupted by a random signal. */
7028 if (ecs
->event_thread
->control
.trap_expected
7029 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7033 fprintf_unfiltered (gdb_stdlog
,
7034 "infrun: need to finish step-over of [%s]\n",
7035 target_pid_to_str (ecs
->event_thread
->ptid
));
7041 /* Check if the current thread is blocked by a single-step
7042 breakpoint of another thread. */
7043 if (ecs
->hit_singlestep_breakpoint
)
7047 fprintf_unfiltered (gdb_stdlog
,
7048 "infrun: need to step [%s] over single-step "
7050 target_pid_to_str (ecs
->ptid
));
7056 /* If this thread needs yet another step-over (e.g., stepping
7057 through a delay slot), do it first before moving on to
7059 if (thread_still_needs_step_over (ecs
->event_thread
))
7063 fprintf_unfiltered (gdb_stdlog
,
7064 "infrun: thread [%s] still needs step-over\n",
7065 target_pid_to_str (ecs
->event_thread
->ptid
));
7071 /* If scheduler locking applies even if not stepping, there's no
7072 need to walk over threads. Above we've checked whether the
7073 current thread is stepping. If some other thread not the
7074 event thread is stepping, then it must be that scheduler
7075 locking is not in effect. */
7076 if (schedlock_applies (ecs
->event_thread
))
7079 /* Otherwise, we no longer expect a trap in the current thread.
7080 Clear the trap_expected flag before switching back -- this is
7081 what keep_going does as well, if we call it. */
7082 ecs
->event_thread
->control
.trap_expected
= 0;
7084 /* Likewise, clear the signal if it should not be passed. */
7085 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7086 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7088 /* Do all pending step-overs before actually proceeding with
7090 if (start_step_over ())
7092 prepare_to_wait (ecs
);
7096 /* Look for the stepping/nexting thread. */
7097 stepping_thread
= NULL
;
7099 ALL_NON_EXITED_THREADS (tp
)
7101 /* Ignore threads of processes the caller is not
7104 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
7107 /* When stepping over a breakpoint, we lock all threads
7108 except the one that needs to move past the breakpoint.
7109 If a non-event thread has this set, the "incomplete
7110 step-over" check above should have caught it earlier. */
7111 if (tp
->control
.trap_expected
)
7113 internal_error (__FILE__
, __LINE__
,
7114 "[%s] has inconsistent state: "
7115 "trap_expected=%d\n",
7116 target_pid_to_str (tp
->ptid
),
7117 tp
->control
.trap_expected
);
7120 /* Did we find the stepping thread? */
7121 if (tp
->control
.step_range_end
)
7123 /* Yep. There should only one though. */
7124 gdb_assert (stepping_thread
== NULL
);
7126 /* The event thread is handled at the top, before we
7128 gdb_assert (tp
!= ecs
->event_thread
);
7130 /* If some thread other than the event thread is
7131 stepping, then scheduler locking can't be in effect,
7132 otherwise we wouldn't have resumed the current event
7133 thread in the first place. */
7134 gdb_assert (!schedlock_applies (tp
));
7136 stepping_thread
= tp
;
7140 if (stepping_thread
!= NULL
)
7143 fprintf_unfiltered (gdb_stdlog
,
7144 "infrun: switching back to stepped thread\n");
7146 if (keep_going_stepped_thread (stepping_thread
))
7148 prepare_to_wait (ecs
);
7157 /* Set a previously stepped thread back to stepping. Returns true on
7158 success, false if the resume is not possible (e.g., the thread
7162 keep_going_stepped_thread (struct thread_info
*tp
)
7164 struct frame_info
*frame
;
7165 struct execution_control_state ecss
;
7166 struct execution_control_state
*ecs
= &ecss
;
7168 /* If the stepping thread exited, then don't try to switch back and
7169 resume it, which could fail in several different ways depending
7170 on the target. Instead, just keep going.
7172 We can find a stepping dead thread in the thread list in two
7175 - The target supports thread exit events, and when the target
7176 tries to delete the thread from the thread list, inferior_ptid
7177 pointed at the exiting thread. In such case, calling
7178 delete_thread does not really remove the thread from the list;
7179 instead, the thread is left listed, with 'exited' state.
7181 - The target's debug interface does not support thread exit
7182 events, and so we have no idea whatsoever if the previously
7183 stepping thread is still alive. For that reason, we need to
7184 synchronously query the target now. */
7186 if (is_exited (tp
->ptid
)
7187 || !target_thread_alive (tp
->ptid
))
7190 fprintf_unfiltered (gdb_stdlog
,
7191 "infrun: not resuming previously "
7192 "stepped thread, it has vanished\n");
7194 delete_thread (tp
->ptid
);
7199 fprintf_unfiltered (gdb_stdlog
,
7200 "infrun: resuming previously stepped thread\n");
7202 reset_ecs (ecs
, tp
);
7203 switch_to_thread (tp
->ptid
);
7205 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7206 frame
= get_current_frame ();
7208 /* If the PC of the thread we were trying to single-step has
7209 changed, then that thread has trapped or been signaled, but the
7210 event has not been reported to GDB yet. Re-poll the target
7211 looking for this particular thread's event (i.e. temporarily
7212 enable schedlock) by:
7214 - setting a break at the current PC
7215 - resuming that particular thread, only (by setting trap
7218 This prevents us continuously moving the single-step breakpoint
7219 forward, one instruction at a time, overstepping. */
7221 if (stop_pc
!= tp
->prev_pc
)
7226 fprintf_unfiltered (gdb_stdlog
,
7227 "infrun: expected thread advanced also (%s -> %s)\n",
7228 paddress (target_gdbarch (), tp
->prev_pc
),
7229 paddress (target_gdbarch (), stop_pc
));
7231 /* Clear the info of the previous step-over, as it's no longer
7232 valid (if the thread was trying to step over a breakpoint, it
7233 has already succeeded). It's what keep_going would do too,
7234 if we called it. Do this before trying to insert the sss
7235 breakpoint, otherwise if we were previously trying to step
7236 over this exact address in another thread, the breakpoint is
7238 clear_step_over_info ();
7239 tp
->control
.trap_expected
= 0;
7241 insert_single_step_breakpoint (get_frame_arch (frame
),
7242 get_frame_address_space (frame
),
7246 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7247 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7252 fprintf_unfiltered (gdb_stdlog
,
7253 "infrun: expected thread still hasn't advanced\n");
7255 keep_going_pass_signal (ecs
);
7260 /* Is thread TP in the middle of (software or hardware)
7261 single-stepping? (Note the result of this function must never be
7262 passed directly as target_resume's STEP parameter.) */
7265 currently_stepping (struct thread_info
*tp
)
7267 return ((tp
->control
.step_range_end
7268 && tp
->control
.step_resume_breakpoint
== NULL
)
7269 || tp
->control
.trap_expected
7270 || tp
->stepped_breakpoint
7271 || bpstat_should_step ());
7274 /* Inferior has stepped into a subroutine call with source code that
7275 we should not step over. Do step to the first line of code in
7279 handle_step_into_function (struct gdbarch
*gdbarch
,
7280 struct execution_control_state
*ecs
)
7282 fill_in_stop_func (gdbarch
, ecs
);
7284 compunit_symtab
*cust
= find_pc_compunit_symtab (stop_pc
);
7285 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7286 ecs
->stop_func_start
7287 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7289 symtab_and_line stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7290 /* Use the step_resume_break to step until the end of the prologue,
7291 even if that involves jumps (as it seems to on the vax under
7293 /* If the prologue ends in the middle of a source line, continue to
7294 the end of that source line (if it is still within the function).
7295 Otherwise, just go to end of prologue. */
7296 if (stop_func_sal
.end
7297 && stop_func_sal
.pc
!= ecs
->stop_func_start
7298 && stop_func_sal
.end
< ecs
->stop_func_end
)
7299 ecs
->stop_func_start
= stop_func_sal
.end
;
7301 /* Architectures which require breakpoint adjustment might not be able
7302 to place a breakpoint at the computed address. If so, the test
7303 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7304 ecs->stop_func_start to an address at which a breakpoint may be
7305 legitimately placed.
7307 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7308 made, GDB will enter an infinite loop when stepping through
7309 optimized code consisting of VLIW instructions which contain
7310 subinstructions corresponding to different source lines. On
7311 FR-V, it's not permitted to place a breakpoint on any but the
7312 first subinstruction of a VLIW instruction. When a breakpoint is
7313 set, GDB will adjust the breakpoint address to the beginning of
7314 the VLIW instruction. Thus, we need to make the corresponding
7315 adjustment here when computing the stop address. */
7317 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7319 ecs
->stop_func_start
7320 = gdbarch_adjust_breakpoint_address (gdbarch
,
7321 ecs
->stop_func_start
);
7324 if (ecs
->stop_func_start
== stop_pc
)
7326 /* We are already there: stop now. */
7327 end_stepping_range (ecs
);
7332 /* Put the step-breakpoint there and go until there. */
7333 symtab_and_line sr_sal
;
7334 sr_sal
.pc
= ecs
->stop_func_start
;
7335 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7336 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7338 /* Do not specify what the fp should be when we stop since on
7339 some machines the prologue is where the new fp value is
7341 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7343 /* And make sure stepping stops right away then. */
7344 ecs
->event_thread
->control
.step_range_end
7345 = ecs
->event_thread
->control
.step_range_start
;
7350 /* Inferior has stepped backward into a subroutine call with source
7351 code that we should not step over. Do step to the beginning of the
7352 last line of code in it. */
7355 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7356 struct execution_control_state
*ecs
)
7358 struct compunit_symtab
*cust
;
7359 struct symtab_and_line stop_func_sal
;
7361 fill_in_stop_func (gdbarch
, ecs
);
7363 cust
= find_pc_compunit_symtab (stop_pc
);
7364 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7365 ecs
->stop_func_start
7366 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7368 stop_func_sal
= find_pc_line (stop_pc
, 0);
7370 /* OK, we're just going to keep stepping here. */
7371 if (stop_func_sal
.pc
== stop_pc
)
7373 /* We're there already. Just stop stepping now. */
7374 end_stepping_range (ecs
);
7378 /* Else just reset the step range and keep going.
7379 No step-resume breakpoint, they don't work for
7380 epilogues, which can have multiple entry paths. */
7381 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7382 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7388 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7389 This is used to both functions and to skip over code. */
7392 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7393 struct symtab_and_line sr_sal
,
7394 struct frame_id sr_id
,
7395 enum bptype sr_type
)
7397 /* There should never be more than one step-resume or longjmp-resume
7398 breakpoint per thread, so we should never be setting a new
7399 step_resume_breakpoint when one is already active. */
7400 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7401 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7404 fprintf_unfiltered (gdb_stdlog
,
7405 "infrun: inserting step-resume breakpoint at %s\n",
7406 paddress (gdbarch
, sr_sal
.pc
));
7408 inferior_thread ()->control
.step_resume_breakpoint
7409 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7413 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7414 struct symtab_and_line sr_sal
,
7415 struct frame_id sr_id
)
7417 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7422 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7423 This is used to skip a potential signal handler.
7425 This is called with the interrupted function's frame. The signal
7426 handler, when it returns, will resume the interrupted function at
7430 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7432 gdb_assert (return_frame
!= NULL
);
7434 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
7436 symtab_and_line sr_sal
;
7437 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7438 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7439 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7441 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7442 get_stack_frame_id (return_frame
),
7446 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7447 is used to skip a function after stepping into it (for "next" or if
7448 the called function has no debugging information).
7450 The current function has almost always been reached by single
7451 stepping a call or return instruction. NEXT_FRAME belongs to the
7452 current function, and the breakpoint will be set at the caller's
7455 This is a separate function rather than reusing
7456 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7457 get_prev_frame, which may stop prematurely (see the implementation
7458 of frame_unwind_caller_id for an example). */
7461 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7463 /* We shouldn't have gotten here if we don't know where the call site
7465 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7467 struct gdbarch
*gdbarch
= frame_unwind_caller_arch (next_frame
);
7469 symtab_and_line sr_sal
;
7470 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7471 frame_unwind_caller_pc (next_frame
));
7472 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7473 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7475 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7476 frame_unwind_caller_id (next_frame
));
7479 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7480 new breakpoint at the target of a jmp_buf. The handling of
7481 longjmp-resume uses the same mechanisms used for handling
7482 "step-resume" breakpoints. */
7485 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7487 /* There should never be more than one longjmp-resume breakpoint per
7488 thread, so we should never be setting a new
7489 longjmp_resume_breakpoint when one is already active. */
7490 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7493 fprintf_unfiltered (gdb_stdlog
,
7494 "infrun: inserting longjmp-resume breakpoint at %s\n",
7495 paddress (gdbarch
, pc
));
7497 inferior_thread ()->control
.exception_resume_breakpoint
=
7498 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7501 /* Insert an exception resume breakpoint. TP is the thread throwing
7502 the exception. The block B is the block of the unwinder debug hook
7503 function. FRAME is the frame corresponding to the call to this
7504 function. SYM is the symbol of the function argument holding the
7505 target PC of the exception. */
7508 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7509 const struct block
*b
,
7510 struct frame_info
*frame
,
7515 struct block_symbol vsym
;
7516 struct value
*value
;
7518 struct breakpoint
*bp
;
7520 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
7521 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7522 /* If the value was optimized out, revert to the old behavior. */
7523 if (! value_optimized_out (value
))
7525 handler
= value_as_address (value
);
7528 fprintf_unfiltered (gdb_stdlog
,
7529 "infrun: exception resume at %lx\n",
7530 (unsigned long) handler
);
7532 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7533 handler
, bp_exception_resume
);
7535 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7538 bp
->thread
= tp
->global_num
;
7539 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7542 CATCH (e
, RETURN_MASK_ERROR
)
7544 /* We want to ignore errors here. */
7549 /* A helper for check_exception_resume that sets an
7550 exception-breakpoint based on a SystemTap probe. */
7553 insert_exception_resume_from_probe (struct thread_info
*tp
,
7554 const struct bound_probe
*probe
,
7555 struct frame_info
*frame
)
7557 struct value
*arg_value
;
7559 struct breakpoint
*bp
;
7561 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7565 handler
= value_as_address (arg_value
);
7568 fprintf_unfiltered (gdb_stdlog
,
7569 "infrun: exception resume at %s\n",
7570 paddress (get_objfile_arch (probe
->objfile
),
7573 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7574 handler
, bp_exception_resume
);
7575 bp
->thread
= tp
->global_num
;
7576 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7579 /* This is called when an exception has been intercepted. Check to
7580 see whether the exception's destination is of interest, and if so,
7581 set an exception resume breakpoint there. */
7584 check_exception_resume (struct execution_control_state
*ecs
,
7585 struct frame_info
*frame
)
7587 struct bound_probe probe
;
7588 struct symbol
*func
;
7590 /* First see if this exception unwinding breakpoint was set via a
7591 SystemTap probe point. If so, the probe has two arguments: the
7592 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7593 set a breakpoint there. */
7594 probe
= find_probe_by_pc (get_frame_pc (frame
));
7597 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7601 func
= get_frame_function (frame
);
7607 const struct block
*b
;
7608 struct block_iterator iter
;
7612 /* The exception breakpoint is a thread-specific breakpoint on
7613 the unwinder's debug hook, declared as:
7615 void _Unwind_DebugHook (void *cfa, void *handler);
7617 The CFA argument indicates the frame to which control is
7618 about to be transferred. HANDLER is the destination PC.
7620 We ignore the CFA and set a temporary breakpoint at HANDLER.
7621 This is not extremely efficient but it avoids issues in gdb
7622 with computing the DWARF CFA, and it also works even in weird
7623 cases such as throwing an exception from inside a signal
7626 b
= SYMBOL_BLOCK_VALUE (func
);
7627 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7629 if (!SYMBOL_IS_ARGUMENT (sym
))
7636 insert_exception_resume_breakpoint (ecs
->event_thread
,
7642 CATCH (e
, RETURN_MASK_ERROR
)
7649 stop_waiting (struct execution_control_state
*ecs
)
7652 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7654 /* Let callers know we don't want to wait for the inferior anymore. */
7655 ecs
->wait_some_more
= 0;
7657 /* If all-stop, but the target is always in non-stop mode, stop all
7658 threads now that we're presenting the stop to the user. */
7659 if (!non_stop
&& target_is_non_stop_p ())
7660 stop_all_threads ();
7663 /* Like keep_going, but passes the signal to the inferior, even if the
7664 signal is set to nopass. */
7667 keep_going_pass_signal (struct execution_control_state
*ecs
)
7669 /* Make sure normal_stop is called if we get a QUIT handled before
7671 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
7673 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7674 gdb_assert (!ecs
->event_thread
->resumed
);
7676 /* Save the pc before execution, to compare with pc after stop. */
7677 ecs
->event_thread
->prev_pc
7678 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7680 if (ecs
->event_thread
->control
.trap_expected
)
7682 struct thread_info
*tp
= ecs
->event_thread
;
7685 fprintf_unfiltered (gdb_stdlog
,
7686 "infrun: %s has trap_expected set, "
7687 "resuming to collect trap\n",
7688 target_pid_to_str (tp
->ptid
));
7690 /* We haven't yet gotten our trap, and either: intercepted a
7691 non-signal event (e.g., a fork); or took a signal which we
7692 are supposed to pass through to the inferior. Simply
7694 discard_cleanups (old_cleanups
);
7695 resume (ecs
->event_thread
->suspend
.stop_signal
);
7697 else if (step_over_info_valid_p ())
7699 /* Another thread is stepping over a breakpoint in-line. If
7700 this thread needs a step-over too, queue the request. In
7701 either case, this resume must be deferred for later. */
7702 struct thread_info
*tp
= ecs
->event_thread
;
7704 if (ecs
->hit_singlestep_breakpoint
7705 || thread_still_needs_step_over (tp
))
7708 fprintf_unfiltered (gdb_stdlog
,
7709 "infrun: step-over already in progress: "
7710 "step-over for %s deferred\n",
7711 target_pid_to_str (tp
->ptid
));
7712 thread_step_over_chain_enqueue (tp
);
7717 fprintf_unfiltered (gdb_stdlog
,
7718 "infrun: step-over in progress: "
7719 "resume of %s deferred\n",
7720 target_pid_to_str (tp
->ptid
));
7723 discard_cleanups (old_cleanups
);
7727 struct regcache
*regcache
= get_current_regcache ();
7730 step_over_what step_what
;
7732 /* Either the trap was not expected, but we are continuing
7733 anyway (if we got a signal, the user asked it be passed to
7736 We got our expected trap, but decided we should resume from
7739 We're going to run this baby now!
7741 Note that insert_breakpoints won't try to re-insert
7742 already inserted breakpoints. Therefore, we don't
7743 care if breakpoints were already inserted, or not. */
7745 /* If we need to step over a breakpoint, and we're not using
7746 displaced stepping to do so, insert all breakpoints
7747 (watchpoints, etc.) but the one we're stepping over, step one
7748 instruction, and then re-insert the breakpoint when that step
7751 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7753 remove_bp
= (ecs
->hit_singlestep_breakpoint
7754 || (step_what
& STEP_OVER_BREAKPOINT
));
7755 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7757 /* We can't use displaced stepping if we need to step past a
7758 watchpoint. The instruction copied to the scratch pad would
7759 still trigger the watchpoint. */
7761 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7763 set_step_over_info (get_regcache_aspace (regcache
),
7764 regcache_read_pc (regcache
), remove_wps
,
7765 ecs
->event_thread
->global_num
);
7767 else if (remove_wps
)
7768 set_step_over_info (NULL
, 0, remove_wps
, -1);
7770 /* If we now need to do an in-line step-over, we need to stop
7771 all other threads. Note this must be done before
7772 insert_breakpoints below, because that removes the breakpoint
7773 we're about to step over, otherwise other threads could miss
7775 if (step_over_info_valid_p () && target_is_non_stop_p ())
7776 stop_all_threads ();
7778 /* Stop stepping if inserting breakpoints fails. */
7781 insert_breakpoints ();
7783 CATCH (e
, RETURN_MASK_ERROR
)
7785 exception_print (gdb_stderr
, e
);
7787 discard_cleanups (old_cleanups
);
7792 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7794 discard_cleanups (old_cleanups
);
7795 resume (ecs
->event_thread
->suspend
.stop_signal
);
7798 prepare_to_wait (ecs
);
7801 /* Called when we should continue running the inferior, because the
7802 current event doesn't cause a user visible stop. This does the
7803 resuming part; waiting for the next event is done elsewhere. */
7806 keep_going (struct execution_control_state
*ecs
)
7808 if (ecs
->event_thread
->control
.trap_expected
7809 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7810 ecs
->event_thread
->control
.trap_expected
= 0;
7812 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7813 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7814 keep_going_pass_signal (ecs
);
7817 /* This function normally comes after a resume, before
7818 handle_inferior_event exits. It takes care of any last bits of
7819 housekeeping, and sets the all-important wait_some_more flag. */
7822 prepare_to_wait (struct execution_control_state
*ecs
)
7825 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7827 ecs
->wait_some_more
= 1;
7829 if (!target_is_async_p ())
7830 mark_infrun_async_event_handler ();
7833 /* We are done with the step range of a step/next/si/ni command.
7834 Called once for each n of a "step n" operation. */
7837 end_stepping_range (struct execution_control_state
*ecs
)
7839 ecs
->event_thread
->control
.stop_step
= 1;
7843 /* Several print_*_reason functions to print why the inferior has stopped.
7844 We always print something when the inferior exits, or receives a signal.
7845 The rest of the cases are dealt with later on in normal_stop and
7846 print_it_typical. Ideally there should be a call to one of these
7847 print_*_reason functions functions from handle_inferior_event each time
7848 stop_waiting is called.
7850 Note that we don't call these directly, instead we delegate that to
7851 the interpreters, through observers. Interpreters then call these
7852 with whatever uiout is right. */
7855 print_end_stepping_range_reason (struct ui_out
*uiout
)
7857 /* For CLI-like interpreters, print nothing. */
7859 if (uiout
->is_mi_like_p ())
7861 uiout
->field_string ("reason",
7862 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7867 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7869 annotate_signalled ();
7870 if (uiout
->is_mi_like_p ())
7872 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7873 uiout
->text ("\nProgram terminated with signal ");
7874 annotate_signal_name ();
7875 uiout
->field_string ("signal-name",
7876 gdb_signal_to_name (siggnal
));
7877 annotate_signal_name_end ();
7879 annotate_signal_string ();
7880 uiout
->field_string ("signal-meaning",
7881 gdb_signal_to_string (siggnal
));
7882 annotate_signal_string_end ();
7883 uiout
->text (".\n");
7884 uiout
->text ("The program no longer exists.\n");
7888 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7890 struct inferior
*inf
= current_inferior ();
7891 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7893 annotate_exited (exitstatus
);
7896 if (uiout
->is_mi_like_p ())
7897 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
7898 uiout
->text ("[Inferior ");
7899 uiout
->text (plongest (inf
->num
));
7901 uiout
->text (pidstr
);
7902 uiout
->text (") exited with code ");
7903 uiout
->field_fmt ("exit-code", "0%o", (unsigned int) exitstatus
);
7904 uiout
->text ("]\n");
7908 if (uiout
->is_mi_like_p ())
7910 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7911 uiout
->text ("[Inferior ");
7912 uiout
->text (plongest (inf
->num
));
7914 uiout
->text (pidstr
);
7915 uiout
->text (") exited normally]\n");
7919 /* Some targets/architectures can do extra processing/display of
7920 segmentation faults. E.g., Intel MPX boundary faults.
7921 Call the architecture dependent function to handle the fault. */
7924 handle_segmentation_fault (struct ui_out
*uiout
)
7926 struct regcache
*regcache
= get_current_regcache ();
7927 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7929 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7930 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7934 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7936 struct thread_info
*thr
= inferior_thread ();
7940 if (uiout
->is_mi_like_p ())
7942 else if (show_thread_that_caused_stop ())
7946 uiout
->text ("\nThread ");
7947 uiout
->field_fmt ("thread-id", "%s", print_thread_id (thr
));
7949 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7952 uiout
->text (" \"");
7953 uiout
->field_fmt ("name", "%s", name
);
7958 uiout
->text ("\nProgram");
7960 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
7961 uiout
->text (" stopped");
7964 uiout
->text (" received signal ");
7965 annotate_signal_name ();
7966 if (uiout
->is_mi_like_p ())
7968 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
7969 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
7970 annotate_signal_name_end ();
7972 annotate_signal_string ();
7973 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
7975 if (siggnal
== GDB_SIGNAL_SEGV
)
7976 handle_segmentation_fault (uiout
);
7978 annotate_signal_string_end ();
7980 uiout
->text (".\n");
7984 print_no_history_reason (struct ui_out
*uiout
)
7986 uiout
->text ("\nNo more reverse-execution history.\n");
7989 /* Print current location without a level number, if we have changed
7990 functions or hit a breakpoint. Print source line if we have one.
7991 bpstat_print contains the logic deciding in detail what to print,
7992 based on the event(s) that just occurred. */
7995 print_stop_location (struct target_waitstatus
*ws
)
7998 enum print_what source_flag
;
7999 int do_frame_printing
= 1;
8000 struct thread_info
*tp
= inferior_thread ();
8002 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8006 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8007 should) carry around the function and does (or should) use
8008 that when doing a frame comparison. */
8009 if (tp
->control
.stop_step
8010 && frame_id_eq (tp
->control
.step_frame_id
,
8011 get_frame_id (get_current_frame ()))
8012 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
8014 /* Finished step, just print source line. */
8015 source_flag
= SRC_LINE
;
8019 /* Print location and source line. */
8020 source_flag
= SRC_AND_LOC
;
8023 case PRINT_SRC_AND_LOC
:
8024 /* Print location and source line. */
8025 source_flag
= SRC_AND_LOC
;
8027 case PRINT_SRC_ONLY
:
8028 source_flag
= SRC_LINE
;
8031 /* Something bogus. */
8032 source_flag
= SRC_LINE
;
8033 do_frame_printing
= 0;
8036 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8039 /* The behavior of this routine with respect to the source
8041 SRC_LINE: Print only source line
8042 LOCATION: Print only location
8043 SRC_AND_LOC: Print location and source line. */
8044 if (do_frame_printing
)
8045 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8051 print_stop_event (struct ui_out
*uiout
)
8053 struct target_waitstatus last
;
8055 struct thread_info
*tp
;
8057 get_last_target_status (&last_ptid
, &last
);
8060 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8062 print_stop_location (&last
);
8064 /* Display the auto-display expressions. */
8068 tp
= inferior_thread ();
8069 if (tp
->thread_fsm
!= NULL
8070 && thread_fsm_finished_p (tp
->thread_fsm
))
8072 struct return_value_info
*rv
;
8074 rv
= thread_fsm_return_value (tp
->thread_fsm
);
8076 print_return_value (uiout
, rv
);
8083 maybe_remove_breakpoints (void)
8085 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
8087 if (remove_breakpoints ())
8089 target_terminal_ours_for_output ();
8090 printf_filtered (_("Cannot remove breakpoints because "
8091 "program is no longer writable.\nFurther "
8092 "execution is probably impossible.\n"));
8097 /* The execution context that just caused a normal stop. */
8104 /* The event PTID. */
8108 /* If stopp for a thread event, this is the thread that caused the
8110 struct thread_info
*thread
;
8112 /* The inferior that caused the stop. */
8116 /* Returns a new stop context. If stopped for a thread event, this
8117 takes a strong reference to the thread. */
8119 static struct stop_context
*
8120 save_stop_context (void)
8122 struct stop_context
*sc
= XNEW (struct stop_context
);
8124 sc
->stop_id
= get_stop_id ();
8125 sc
->ptid
= inferior_ptid
;
8126 sc
->inf_num
= current_inferior ()->num
;
8128 if (!ptid_equal (inferior_ptid
, null_ptid
))
8130 /* Take a strong reference so that the thread can't be deleted
8132 sc
->thread
= inferior_thread ();
8133 sc
->thread
->incref ();
8141 /* Release a stop context previously created with save_stop_context.
8142 Releases the strong reference to the thread as well. */
8145 release_stop_context_cleanup (void *arg
)
8147 struct stop_context
*sc
= (struct stop_context
*) arg
;
8149 if (sc
->thread
!= NULL
)
8150 sc
->thread
->decref ();
8154 /* Return true if the current context no longer matches the saved stop
8158 stop_context_changed (struct stop_context
*prev
)
8160 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
8162 if (prev
->inf_num
!= current_inferior ()->num
)
8164 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
8166 if (get_stop_id () != prev
->stop_id
)
8176 struct target_waitstatus last
;
8178 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
8181 get_last_target_status (&last_ptid
, &last
);
8185 /* If an exception is thrown from this point on, make sure to
8186 propagate GDB's knowledge of the executing state to the
8187 frontend/user running state. A QUIT is an easy exception to see
8188 here, so do this before any filtered output. */
8190 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
8191 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8192 || last
.kind
== TARGET_WAITKIND_EXITED
)
8194 /* On some targets, we may still have live threads in the
8195 inferior when we get a process exit event. E.g., for
8196 "checkpoint", when the current checkpoint/fork exits,
8197 linux-fork.c automatically switches to another fork from
8198 within target_mourn_inferior. */
8199 if (!ptid_equal (inferior_ptid
, null_ptid
))
8201 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8202 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8205 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8206 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8208 /* As we're presenting a stop, and potentially removing breakpoints,
8209 update the thread list so we can tell whether there are threads
8210 running on the target. With target remote, for example, we can
8211 only learn about new threads when we explicitly update the thread
8212 list. Do this before notifying the interpreters about signal
8213 stops, end of stepping ranges, etc., so that the "new thread"
8214 output is emitted before e.g., "Program received signal FOO",
8215 instead of after. */
8216 update_thread_list ();
8218 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8219 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
8221 /* As with the notification of thread events, we want to delay
8222 notifying the user that we've switched thread context until
8223 the inferior actually stops.
8225 There's no point in saying anything if the inferior has exited.
8226 Note that SIGNALLED here means "exited with a signal", not
8227 "received a signal".
8229 Also skip saying anything in non-stop mode. In that mode, as we
8230 don't want GDB to switch threads behind the user's back, to avoid
8231 races where the user is typing a command to apply to thread x,
8232 but GDB switches to thread y before the user finishes entering
8233 the command, fetch_inferior_event installs a cleanup to restore
8234 the current thread back to the thread the user had selected right
8235 after this event is handled, so we're not really switching, only
8236 informing of a stop. */
8238 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8239 && target_has_execution
8240 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8241 && last
.kind
!= TARGET_WAITKIND_EXITED
8242 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8244 SWITCH_THRU_ALL_UIS ()
8246 target_terminal_ours_for_output ();
8247 printf_filtered (_("[Switching to %s]\n"),
8248 target_pid_to_str (inferior_ptid
));
8249 annotate_thread_changed ();
8251 previous_inferior_ptid
= inferior_ptid
;
8254 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8256 SWITCH_THRU_ALL_UIS ()
8257 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8259 target_terminal_ours_for_output ();
8260 printf_filtered (_("No unwaited-for children left.\n"));
8264 /* Note: this depends on the update_thread_list call above. */
8265 maybe_remove_breakpoints ();
8267 /* If an auto-display called a function and that got a signal,
8268 delete that auto-display to avoid an infinite recursion. */
8270 if (stopped_by_random_signal
)
8271 disable_current_display ();
8273 SWITCH_THRU_ALL_UIS ()
8275 async_enable_stdin ();
8278 /* Let the user/frontend see the threads as stopped. */
8279 do_cleanups (old_chain
);
8281 /* Select innermost stack frame - i.e., current frame is frame 0,
8282 and current location is based on that. Handle the case where the
8283 dummy call is returning after being stopped. E.g. the dummy call
8284 previously hit a breakpoint. (If the dummy call returns
8285 normally, we won't reach here.) Do this before the stop hook is
8286 run, so that it doesn't get to see the temporary dummy frame,
8287 which is not where we'll present the stop. */
8288 if (has_stack_frames ())
8290 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8292 /* Pop the empty frame that contains the stack dummy. This
8293 also restores inferior state prior to the call (struct
8294 infcall_suspend_state). */
8295 struct frame_info
*frame
= get_current_frame ();
8297 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8299 /* frame_pop calls reinit_frame_cache as the last thing it
8300 does which means there's now no selected frame. */
8303 select_frame (get_current_frame ());
8305 /* Set the current source location. */
8306 set_current_sal_from_frame (get_current_frame ());
8309 /* Look up the hook_stop and run it (CLI internally handles problem
8310 of stop_command's pre-hook not existing). */
8311 if (stop_command
!= NULL
)
8313 struct stop_context
*saved_context
= save_stop_context ();
8314 struct cleanup
*old_chain
8315 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8317 catch_errors (hook_stop_stub
, stop_command
,
8318 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
8320 /* If the stop hook resumes the target, then there's no point in
8321 trying to notify about the previous stop; its context is
8322 gone. Likewise if the command switches thread or inferior --
8323 the observers would print a stop for the wrong
8325 if (stop_context_changed (saved_context
))
8327 do_cleanups (old_chain
);
8330 do_cleanups (old_chain
);
8333 /* Notify observers about the stop. This is where the interpreters
8334 print the stop event. */
8335 if (!ptid_equal (inferior_ptid
, null_ptid
))
8336 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
8339 observer_notify_normal_stop (NULL
, stop_print_frame
);
8341 annotate_stopped ();
8343 if (target_has_execution
)
8345 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8346 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8347 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8348 Delete any breakpoint that is to be deleted at the next stop. */
8349 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8352 /* Try to get rid of automatically added inferiors that are no
8353 longer needed. Keeping those around slows down things linearly.
8354 Note that this never removes the current inferior. */
8361 hook_stop_stub (void *cmd
)
8363 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
8368 signal_stop_state (int signo
)
8370 return signal_stop
[signo
];
8374 signal_print_state (int signo
)
8376 return signal_print
[signo
];
8380 signal_pass_state (int signo
)
8382 return signal_program
[signo
];
8386 signal_cache_update (int signo
)
8390 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8391 signal_cache_update (signo
);
8396 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8397 && signal_print
[signo
] == 0
8398 && signal_program
[signo
] == 1
8399 && signal_catch
[signo
] == 0);
8403 signal_stop_update (int signo
, int state
)
8405 int ret
= signal_stop
[signo
];
8407 signal_stop
[signo
] = state
;
8408 signal_cache_update (signo
);
8413 signal_print_update (int signo
, int state
)
8415 int ret
= signal_print
[signo
];
8417 signal_print
[signo
] = state
;
8418 signal_cache_update (signo
);
8423 signal_pass_update (int signo
, int state
)
8425 int ret
= signal_program
[signo
];
8427 signal_program
[signo
] = state
;
8428 signal_cache_update (signo
);
8432 /* Update the global 'signal_catch' from INFO and notify the
8436 signal_catch_update (const unsigned int *info
)
8440 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8441 signal_catch
[i
] = info
[i
] > 0;
8442 signal_cache_update (-1);
8443 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8447 sig_print_header (void)
8449 printf_filtered (_("Signal Stop\tPrint\tPass "
8450 "to program\tDescription\n"));
8454 sig_print_info (enum gdb_signal oursig
)
8456 const char *name
= gdb_signal_to_name (oursig
);
8457 int name_padding
= 13 - strlen (name
);
8459 if (name_padding
<= 0)
8462 printf_filtered ("%s", name
);
8463 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8464 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8465 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8466 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8467 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8470 /* Specify how various signals in the inferior should be handled. */
8473 handle_command (char *args
, int from_tty
)
8475 int digits
, wordlen
;
8476 int sigfirst
, signum
, siglast
;
8477 enum gdb_signal oursig
;
8480 unsigned char *sigs
;
8484 error_no_arg (_("signal to handle"));
8487 /* Allocate and zero an array of flags for which signals to handle. */
8489 nsigs
= (int) GDB_SIGNAL_LAST
;
8490 sigs
= (unsigned char *) alloca (nsigs
);
8491 memset (sigs
, 0, nsigs
);
8493 /* Break the command line up into args. */
8495 gdb_argv
built_argv (args
);
8497 /* Walk through the args, looking for signal oursigs, signal names, and
8498 actions. Signal numbers and signal names may be interspersed with
8499 actions, with the actions being performed for all signals cumulatively
8500 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8502 for (char *arg
: built_argv
)
8504 wordlen
= strlen (arg
);
8505 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8509 sigfirst
= siglast
= -1;
8511 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8513 /* Apply action to all signals except those used by the
8514 debugger. Silently skip those. */
8517 siglast
= nsigs
- 1;
8519 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8521 SET_SIGS (nsigs
, sigs
, signal_stop
);
8522 SET_SIGS (nsigs
, sigs
, signal_print
);
8524 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8526 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8528 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8530 SET_SIGS (nsigs
, sigs
, signal_print
);
8532 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8534 SET_SIGS (nsigs
, sigs
, signal_program
);
8536 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8538 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8540 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8542 SET_SIGS (nsigs
, sigs
, signal_program
);
8544 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8546 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8547 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8549 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8551 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8553 else if (digits
> 0)
8555 /* It is numeric. The numeric signal refers to our own
8556 internal signal numbering from target.h, not to host/target
8557 signal number. This is a feature; users really should be
8558 using symbolic names anyway, and the common ones like
8559 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8561 sigfirst
= siglast
= (int)
8562 gdb_signal_from_command (atoi (arg
));
8563 if (arg
[digits
] == '-')
8566 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8568 if (sigfirst
> siglast
)
8570 /* Bet he didn't figure we'd think of this case... */
8578 oursig
= gdb_signal_from_name (arg
);
8579 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8581 sigfirst
= siglast
= (int) oursig
;
8585 /* Not a number and not a recognized flag word => complain. */
8586 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8590 /* If any signal numbers or symbol names were found, set flags for
8591 which signals to apply actions to. */
8593 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8595 switch ((enum gdb_signal
) signum
)
8597 case GDB_SIGNAL_TRAP
:
8598 case GDB_SIGNAL_INT
:
8599 if (!allsigs
&& !sigs
[signum
])
8601 if (query (_("%s is used by the debugger.\n\
8602 Are you sure you want to change it? "),
8603 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8609 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8610 gdb_flush (gdb_stdout
);
8615 case GDB_SIGNAL_DEFAULT
:
8616 case GDB_SIGNAL_UNKNOWN
:
8617 /* Make sure that "all" doesn't print these. */
8626 for (signum
= 0; signum
< nsigs
; signum
++)
8629 signal_cache_update (-1);
8630 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8631 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8635 /* Show the results. */
8636 sig_print_header ();
8637 for (; signum
< nsigs
; signum
++)
8639 sig_print_info ((enum gdb_signal
) signum
);
8646 /* Complete the "handle" command. */
8649 handle_completer (struct cmd_list_element
*ignore
,
8650 completion_tracker
&tracker
,
8651 const char *text
, const char *word
)
8653 static const char * const keywords
[] =
8667 signal_completer (ignore
, tracker
, text
, word
);
8668 complete_on_enum (tracker
, keywords
, word
, word
);
8672 gdb_signal_from_command (int num
)
8674 if (num
>= 1 && num
<= 15)
8675 return (enum gdb_signal
) num
;
8676 error (_("Only signals 1-15 are valid as numeric signals.\n\
8677 Use \"info signals\" for a list of symbolic signals."));
8680 /* Print current contents of the tables set by the handle command.
8681 It is possible we should just be printing signals actually used
8682 by the current target (but for things to work right when switching
8683 targets, all signals should be in the signal tables). */
8686 info_signals_command (char *signum_exp
, int from_tty
)
8688 enum gdb_signal oursig
;
8690 sig_print_header ();
8694 /* First see if this is a symbol name. */
8695 oursig
= gdb_signal_from_name (signum_exp
);
8696 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8698 /* No, try numeric. */
8700 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8702 sig_print_info (oursig
);
8706 printf_filtered ("\n");
8707 /* These ugly casts brought to you by the native VAX compiler. */
8708 for (oursig
= GDB_SIGNAL_FIRST
;
8709 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8710 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8714 if (oursig
!= GDB_SIGNAL_UNKNOWN
8715 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8716 sig_print_info (oursig
);
8719 printf_filtered (_("\nUse the \"handle\" command "
8720 "to change these tables.\n"));
8723 /* The $_siginfo convenience variable is a bit special. We don't know
8724 for sure the type of the value until we actually have a chance to
8725 fetch the data. The type can change depending on gdbarch, so it is
8726 also dependent on which thread you have selected.
8728 1. making $_siginfo be an internalvar that creates a new value on
8731 2. making the value of $_siginfo be an lval_computed value. */
8733 /* This function implements the lval_computed support for reading a
8737 siginfo_value_read (struct value
*v
)
8739 LONGEST transferred
;
8741 /* If we can access registers, so can we access $_siginfo. Likewise
8743 validate_registers_access ();
8746 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8748 value_contents_all_raw (v
),
8750 TYPE_LENGTH (value_type (v
)));
8752 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8753 error (_("Unable to read siginfo"));
8756 /* This function implements the lval_computed support for writing a
8760 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8762 LONGEST transferred
;
8764 /* If we can access registers, so can we access $_siginfo. Likewise
8766 validate_registers_access ();
8768 transferred
= target_write (¤t_target
,
8769 TARGET_OBJECT_SIGNAL_INFO
,
8771 value_contents_all_raw (fromval
),
8773 TYPE_LENGTH (value_type (fromval
)));
8775 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8776 error (_("Unable to write siginfo"));
8779 static const struct lval_funcs siginfo_value_funcs
=
8785 /* Return a new value with the correct type for the siginfo object of
8786 the current thread using architecture GDBARCH. Return a void value
8787 if there's no object available. */
8789 static struct value
*
8790 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8793 if (target_has_stack
8794 && !ptid_equal (inferior_ptid
, null_ptid
)
8795 && gdbarch_get_siginfo_type_p (gdbarch
))
8797 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8799 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8802 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8806 /* infcall_suspend_state contains state about the program itself like its
8807 registers and any signal it received when it last stopped.
8808 This state must be restored regardless of how the inferior function call
8809 ends (either successfully, or after it hits a breakpoint or signal)
8810 if the program is to properly continue where it left off. */
8812 struct infcall_suspend_state
8814 struct thread_suspend_state thread_suspend
;
8818 struct regcache
*registers
;
8820 /* Format of SIGINFO_DATA or NULL if it is not present. */
8821 struct gdbarch
*siginfo_gdbarch
;
8823 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8824 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8825 content would be invalid. */
8826 gdb_byte
*siginfo_data
;
8829 struct infcall_suspend_state
*
8830 save_infcall_suspend_state (void)
8832 struct infcall_suspend_state
*inf_state
;
8833 struct thread_info
*tp
= inferior_thread ();
8834 struct regcache
*regcache
= get_current_regcache ();
8835 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8836 gdb_byte
*siginfo_data
= NULL
;
8838 if (gdbarch_get_siginfo_type_p (gdbarch
))
8840 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8841 size_t len
= TYPE_LENGTH (type
);
8842 struct cleanup
*back_to
;
8844 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8845 back_to
= make_cleanup (xfree
, siginfo_data
);
8847 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8848 siginfo_data
, 0, len
) == len
)
8849 discard_cleanups (back_to
);
8852 /* Errors ignored. */
8853 do_cleanups (back_to
);
8854 siginfo_data
= NULL
;
8858 inf_state
= XCNEW (struct infcall_suspend_state
);
8862 inf_state
->siginfo_gdbarch
= gdbarch
;
8863 inf_state
->siginfo_data
= siginfo_data
;
8866 inf_state
->thread_suspend
= tp
->suspend
;
8868 /* run_inferior_call will not use the signal due to its `proceed' call with
8869 GDB_SIGNAL_0 anyway. */
8870 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8872 inf_state
->stop_pc
= stop_pc
;
8874 inf_state
->registers
= regcache_dup (regcache
);
8879 /* Restore inferior session state to INF_STATE. */
8882 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8884 struct thread_info
*tp
= inferior_thread ();
8885 struct regcache
*regcache
= get_current_regcache ();
8886 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8888 tp
->suspend
= inf_state
->thread_suspend
;
8890 stop_pc
= inf_state
->stop_pc
;
8892 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8894 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8896 /* Errors ignored. */
8897 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8898 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8901 /* The inferior can be gone if the user types "print exit(0)"
8902 (and perhaps other times). */
8903 if (target_has_execution
)
8904 /* NB: The register write goes through to the target. */
8905 regcache_cpy (regcache
, inf_state
->registers
);
8907 discard_infcall_suspend_state (inf_state
);
8911 do_restore_infcall_suspend_state_cleanup (void *state
)
8913 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
8917 make_cleanup_restore_infcall_suspend_state
8918 (struct infcall_suspend_state
*inf_state
)
8920 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8924 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8926 regcache_xfree (inf_state
->registers
);
8927 xfree (inf_state
->siginfo_data
);
8932 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8934 return inf_state
->registers
;
8937 /* infcall_control_state contains state regarding gdb's control of the
8938 inferior itself like stepping control. It also contains session state like
8939 the user's currently selected frame. */
8941 struct infcall_control_state
8943 struct thread_control_state thread_control
;
8944 struct inferior_control_state inferior_control
;
8947 enum stop_stack_kind stop_stack_dummy
;
8948 int stopped_by_random_signal
;
8950 /* ID if the selected frame when the inferior function call was made. */
8951 struct frame_id selected_frame_id
;
8954 /* Save all of the information associated with the inferior<==>gdb
8957 struct infcall_control_state
*
8958 save_infcall_control_state (void)
8960 struct infcall_control_state
*inf_status
=
8961 XNEW (struct infcall_control_state
);
8962 struct thread_info
*tp
= inferior_thread ();
8963 struct inferior
*inf
= current_inferior ();
8965 inf_status
->thread_control
= tp
->control
;
8966 inf_status
->inferior_control
= inf
->control
;
8968 tp
->control
.step_resume_breakpoint
= NULL
;
8969 tp
->control
.exception_resume_breakpoint
= NULL
;
8971 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8972 chain. If caller's caller is walking the chain, they'll be happier if we
8973 hand them back the original chain when restore_infcall_control_state is
8975 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
8978 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
8979 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
8981 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
8987 restore_selected_frame (void *args
)
8989 struct frame_id
*fid
= (struct frame_id
*) args
;
8990 struct frame_info
*frame
;
8992 frame
= frame_find_by_id (*fid
);
8994 /* If inf_status->selected_frame_id is NULL, there was no previously
8998 warning (_("Unable to restore previously selected frame."));
9002 select_frame (frame
);
9007 /* Restore inferior session state to INF_STATUS. */
9010 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9012 struct thread_info
*tp
= inferior_thread ();
9013 struct inferior
*inf
= current_inferior ();
9015 if (tp
->control
.step_resume_breakpoint
)
9016 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9018 if (tp
->control
.exception_resume_breakpoint
)
9019 tp
->control
.exception_resume_breakpoint
->disposition
9020 = disp_del_at_next_stop
;
9022 /* Handle the bpstat_copy of the chain. */
9023 bpstat_clear (&tp
->control
.stop_bpstat
);
9025 tp
->control
= inf_status
->thread_control
;
9026 inf
->control
= inf_status
->inferior_control
;
9029 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9030 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9032 if (target_has_stack
)
9034 /* The point of catch_errors is that if the stack is clobbered,
9035 walking the stack might encounter a garbage pointer and
9036 error() trying to dereference it. */
9038 (restore_selected_frame
, &inf_status
->selected_frame_id
,
9039 "Unable to restore previously selected frame:\n",
9040 RETURN_MASK_ERROR
) == 0)
9041 /* Error in restoring the selected frame. Select the innermost
9043 select_frame (get_current_frame ());
9050 do_restore_infcall_control_state_cleanup (void *sts
)
9052 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
9056 make_cleanup_restore_infcall_control_state
9057 (struct infcall_control_state
*inf_status
)
9059 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
9063 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9065 if (inf_status
->thread_control
.step_resume_breakpoint
)
9066 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9067 = disp_del_at_next_stop
;
9069 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9070 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9071 = disp_del_at_next_stop
;
9073 /* See save_infcall_control_state for info on stop_bpstat. */
9074 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9082 clear_exit_convenience_vars (void)
9084 clear_internalvar (lookup_internalvar ("_exitsignal"));
9085 clear_internalvar (lookup_internalvar ("_exitcode"));
9089 /* User interface for reverse debugging:
9090 Set exec-direction / show exec-direction commands
9091 (returns error unless target implements to_set_exec_direction method). */
9093 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9094 static const char exec_forward
[] = "forward";
9095 static const char exec_reverse
[] = "reverse";
9096 static const char *exec_direction
= exec_forward
;
9097 static const char *const exec_direction_names
[] = {
9104 set_exec_direction_func (char *args
, int from_tty
,
9105 struct cmd_list_element
*cmd
)
9107 if (target_can_execute_reverse
)
9109 if (!strcmp (exec_direction
, exec_forward
))
9110 execution_direction
= EXEC_FORWARD
;
9111 else if (!strcmp (exec_direction
, exec_reverse
))
9112 execution_direction
= EXEC_REVERSE
;
9116 exec_direction
= exec_forward
;
9117 error (_("Target does not support this operation."));
9122 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9123 struct cmd_list_element
*cmd
, const char *value
)
9125 switch (execution_direction
) {
9127 fprintf_filtered (out
, _("Forward.\n"));
9130 fprintf_filtered (out
, _("Reverse.\n"));
9133 internal_error (__FILE__
, __LINE__
,
9134 _("bogus execution_direction value: %d"),
9135 (int) execution_direction
);
9140 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9141 struct cmd_list_element
*c
, const char *value
)
9143 fprintf_filtered (file
, _("Resuming the execution of threads "
9144 "of all processes is %s.\n"), value
);
9147 /* Implementation of `siginfo' variable. */
9149 static const struct internalvar_funcs siginfo_funcs
=
9156 /* Callback for infrun's target events source. This is marked when a
9157 thread has a pending status to process. */
9160 infrun_async_inferior_event_handler (gdb_client_data data
)
9162 inferior_event_handler (INF_REG_EVENT
, NULL
);
9166 _initialize_infrun (void)
9170 struct cmd_list_element
*c
;
9172 /* Register extra event sources in the event loop. */
9173 infrun_async_inferior_event_token
9174 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9176 add_info ("signals", info_signals_command
, _("\
9177 What debugger does when program gets various signals.\n\
9178 Specify a signal as argument to print info on that signal only."));
9179 add_info_alias ("handle", "signals", 0);
9181 c
= add_com ("handle", class_run
, handle_command
, _("\
9182 Specify how to handle signals.\n\
9183 Usage: handle SIGNAL [ACTIONS]\n\
9184 Args are signals and actions to apply to those signals.\n\
9185 If no actions are specified, the current settings for the specified signals\n\
9186 will be displayed instead.\n\
9188 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9189 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9190 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9191 The special arg \"all\" is recognized to mean all signals except those\n\
9192 used by the debugger, typically SIGTRAP and SIGINT.\n\
9194 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9195 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9196 Stop means reenter debugger if this signal happens (implies print).\n\
9197 Print means print a message if this signal happens.\n\
9198 Pass means let program see this signal; otherwise program doesn't know.\n\
9199 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9200 Pass and Stop may be combined.\n\
9202 Multiple signals may be specified. Signal numbers and signal names\n\
9203 may be interspersed with actions, with the actions being performed for\n\
9204 all signals cumulatively specified."));
9205 set_cmd_completer (c
, handle_completer
);
9208 stop_command
= add_cmd ("stop", class_obscure
,
9209 not_just_help_class_command
, _("\
9210 There is no `stop' command, but you can set a hook on `stop'.\n\
9211 This allows you to set a list of commands to be run each time execution\n\
9212 of the program stops."), &cmdlist
);
9214 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9215 Set inferior debugging."), _("\
9216 Show inferior debugging."), _("\
9217 When non-zero, inferior specific debugging is enabled."),
9220 &setdebuglist
, &showdebuglist
);
9222 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9223 &debug_displaced
, _("\
9224 Set displaced stepping debugging."), _("\
9225 Show displaced stepping debugging."), _("\
9226 When non-zero, displaced stepping specific debugging is enabled."),
9228 show_debug_displaced
,
9229 &setdebuglist
, &showdebuglist
);
9231 add_setshow_boolean_cmd ("non-stop", no_class
,
9233 Set whether gdb controls the inferior in non-stop mode."), _("\
9234 Show whether gdb controls the inferior in non-stop mode."), _("\
9235 When debugging a multi-threaded program and this setting is\n\
9236 off (the default, also called all-stop mode), when one thread stops\n\
9237 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9238 all other threads in the program while you interact with the thread of\n\
9239 interest. When you continue or step a thread, you can allow the other\n\
9240 threads to run, or have them remain stopped, but while you inspect any\n\
9241 thread's state, all threads stop.\n\
9243 In non-stop mode, when one thread stops, other threads can continue\n\
9244 to run freely. You'll be able to step each thread independently,\n\
9245 leave it stopped or free to run as needed."),
9251 numsigs
= (int) GDB_SIGNAL_LAST
;
9252 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9253 signal_print
= XNEWVEC (unsigned char, numsigs
);
9254 signal_program
= XNEWVEC (unsigned char, numsigs
);
9255 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9256 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9257 for (i
= 0; i
< numsigs
; i
++)
9260 signal_print
[i
] = 1;
9261 signal_program
[i
] = 1;
9262 signal_catch
[i
] = 0;
9265 /* Signals caused by debugger's own actions should not be given to
9266 the program afterwards.
9268 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9269 explicitly specifies that it should be delivered to the target
9270 program. Typically, that would occur when a user is debugging a
9271 target monitor on a simulator: the target monitor sets a
9272 breakpoint; the simulator encounters this breakpoint and halts
9273 the simulation handing control to GDB; GDB, noting that the stop
9274 address doesn't map to any known breakpoint, returns control back
9275 to the simulator; the simulator then delivers the hardware
9276 equivalent of a GDB_SIGNAL_TRAP to the program being
9278 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9279 signal_program
[GDB_SIGNAL_INT
] = 0;
9281 /* Signals that are not errors should not normally enter the debugger. */
9282 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9283 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9284 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9285 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9286 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9287 signal_print
[GDB_SIGNAL_PROF
] = 0;
9288 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9289 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9290 signal_stop
[GDB_SIGNAL_IO
] = 0;
9291 signal_print
[GDB_SIGNAL_IO
] = 0;
9292 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9293 signal_print
[GDB_SIGNAL_POLL
] = 0;
9294 signal_stop
[GDB_SIGNAL_URG
] = 0;
9295 signal_print
[GDB_SIGNAL_URG
] = 0;
9296 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9297 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9298 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9299 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9301 /* These signals are used internally by user-level thread
9302 implementations. (See signal(5) on Solaris.) Like the above
9303 signals, a healthy program receives and handles them as part of
9304 its normal operation. */
9305 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9306 signal_print
[GDB_SIGNAL_LWP
] = 0;
9307 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9308 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9309 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9310 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9311 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9312 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9314 /* Update cached state. */
9315 signal_cache_update (-1);
9317 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9318 &stop_on_solib_events
, _("\
9319 Set stopping for shared library events."), _("\
9320 Show stopping for shared library events."), _("\
9321 If nonzero, gdb will give control to the user when the dynamic linker\n\
9322 notifies gdb of shared library events. The most common event of interest\n\
9323 to the user would be loading/unloading of a new library."),
9324 set_stop_on_solib_events
,
9325 show_stop_on_solib_events
,
9326 &setlist
, &showlist
);
9328 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9329 follow_fork_mode_kind_names
,
9330 &follow_fork_mode_string
, _("\
9331 Set debugger response to a program call of fork or vfork."), _("\
9332 Show debugger response to a program call of fork or vfork."), _("\
9333 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9334 parent - the original process is debugged after a fork\n\
9335 child - the new process is debugged after a fork\n\
9336 The unfollowed process will continue to run.\n\
9337 By default, the debugger will follow the parent process."),
9339 show_follow_fork_mode_string
,
9340 &setlist
, &showlist
);
9342 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9343 follow_exec_mode_names
,
9344 &follow_exec_mode_string
, _("\
9345 Set debugger response to a program call of exec."), _("\
9346 Show debugger response to a program call of exec."), _("\
9347 An exec call replaces the program image of a process.\n\
9349 follow-exec-mode can be:\n\
9351 new - the debugger creates a new inferior and rebinds the process\n\
9352 to this new inferior. The program the process was running before\n\
9353 the exec call can be restarted afterwards by restarting the original\n\
9356 same - the debugger keeps the process bound to the same inferior.\n\
9357 The new executable image replaces the previous executable loaded in\n\
9358 the inferior. Restarting the inferior after the exec call restarts\n\
9359 the executable the process was running after the exec call.\n\
9361 By default, the debugger will use the same inferior."),
9363 show_follow_exec_mode_string
,
9364 &setlist
, &showlist
);
9366 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9367 scheduler_enums
, &scheduler_mode
, _("\
9368 Set mode for locking scheduler during execution."), _("\
9369 Show mode for locking scheduler during execution."), _("\
9370 off == no locking (threads may preempt at any time)\n\
9371 on == full locking (no thread except the current thread may run)\n\
9372 This applies to both normal execution and replay mode.\n\
9373 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9374 In this mode, other threads may run during other commands.\n\
9375 This applies to both normal execution and replay mode.\n\
9376 replay == scheduler locked in replay mode and unlocked during normal execution."),
9377 set_schedlock_func
, /* traps on target vector */
9378 show_scheduler_mode
,
9379 &setlist
, &showlist
);
9381 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9382 Set mode for resuming threads of all processes."), _("\
9383 Show mode for resuming threads of all processes."), _("\
9384 When on, execution commands (such as 'continue' or 'next') resume all\n\
9385 threads of all processes. When off (which is the default), execution\n\
9386 commands only resume the threads of the current process. The set of\n\
9387 threads that are resumed is further refined by the scheduler-locking\n\
9388 mode (see help set scheduler-locking)."),
9390 show_schedule_multiple
,
9391 &setlist
, &showlist
);
9393 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9394 Set mode of the step operation."), _("\
9395 Show mode of the step operation."), _("\
9396 When set, doing a step over a function without debug line information\n\
9397 will stop at the first instruction of that function. Otherwise, the\n\
9398 function is skipped and the step command stops at a different source line."),
9400 show_step_stop_if_no_debug
,
9401 &setlist
, &showlist
);
9403 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9404 &can_use_displaced_stepping
, _("\
9405 Set debugger's willingness to use displaced stepping."), _("\
9406 Show debugger's willingness to use displaced stepping."), _("\
9407 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9408 supported by the target architecture. If off, gdb will not use displaced\n\
9409 stepping to step over breakpoints, even if such is supported by the target\n\
9410 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9411 if the target architecture supports it and non-stop mode is active, but will not\n\
9412 use it in all-stop mode (see help set non-stop)."),
9414 show_can_use_displaced_stepping
,
9415 &setlist
, &showlist
);
9417 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9418 &exec_direction
, _("Set direction of execution.\n\
9419 Options are 'forward' or 'reverse'."),
9420 _("Show direction of execution (forward/reverse)."),
9421 _("Tells gdb whether to execute forward or backward."),
9422 set_exec_direction_func
, show_exec_direction_func
,
9423 &setlist
, &showlist
);
9425 /* Set/show detach-on-fork: user-settable mode. */
9427 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9428 Set whether gdb will detach the child of a fork."), _("\
9429 Show whether gdb will detach the child of a fork."), _("\
9430 Tells gdb whether to detach the child of a fork."),
9431 NULL
, NULL
, &setlist
, &showlist
);
9433 /* Set/show disable address space randomization mode. */
9435 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9436 &disable_randomization
, _("\
9437 Set disabling of debuggee's virtual address space randomization."), _("\
9438 Show disabling of debuggee's virtual address space randomization."), _("\
9439 When this mode is on (which is the default), randomization of the virtual\n\
9440 address space is disabled. Standalone programs run with the randomization\n\
9441 enabled by default on some platforms."),
9442 &set_disable_randomization
,
9443 &show_disable_randomization
,
9444 &setlist
, &showlist
);
9446 /* ptid initializations */
9447 inferior_ptid
= null_ptid
;
9448 target_last_wait_ptid
= minus_one_ptid
;
9450 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9451 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9452 observer_attach_thread_exit (infrun_thread_thread_exit
);
9453 observer_attach_inferior_exit (infrun_inferior_exit
);
9455 /* Explicitly create without lookup, since that tries to create a
9456 value with a void typed value, and when we get here, gdbarch
9457 isn't initialized yet. At this point, we're quite sure there
9458 isn't another convenience variable of the same name. */
9459 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9461 add_setshow_boolean_cmd ("observer", no_class
,
9462 &observer_mode_1
, _("\
9463 Set whether gdb controls the inferior in observer mode."), _("\
9464 Show whether gdb controls the inferior in observer mode."), _("\
9465 In observer mode, GDB can get data from the inferior, but not\n\
9466 affect its execution. Registers and memory may not be changed,\n\
9467 breakpoints may not be set, and the program cannot be interrupted\n\