1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2015 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"
67 /* Prototypes for local functions */
69 static void signals_info (char *, int);
71 static void handle_command (char *, int);
73 static void sig_print_info (enum gdb_signal
);
75 static void sig_print_header (void);
77 static void resume_cleanups (void *);
79 static int hook_stop_stub (void *);
81 static int restore_selected_frame (void *);
83 static int follow_fork (void);
85 static int follow_fork_inferior (int follow_child
, int detach_fork
);
87 static void follow_inferior_reset_breakpoints (void);
89 static void set_schedlock_func (char *args
, int from_tty
,
90 struct cmd_list_element
*c
);
92 static int currently_stepping (struct thread_info
*tp
);
94 void _initialize_infrun (void);
96 void nullify_last_target_wait_ptid (void);
98 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
100 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
102 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
104 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
106 /* Asynchronous signal handler registered as event loop source for
107 when we have pending events ready to be passed to the core. */
108 static struct async_event_handler
*infrun_async_inferior_event_token
;
110 /* Stores whether infrun_async was previously enabled or disabled.
111 Starts off as -1, indicating "never enabled/disabled". */
112 static int infrun_is_async
= -1;
117 infrun_async (int enable
)
119 if (infrun_is_async
!= enable
)
121 infrun_is_async
= enable
;
124 fprintf_unfiltered (gdb_stdlog
,
125 "infrun: infrun_async(%d)\n",
129 mark_async_event_handler (infrun_async_inferior_event_token
);
131 clear_async_event_handler (infrun_async_inferior_event_token
);
138 mark_infrun_async_event_handler (void)
140 mark_async_event_handler (infrun_async_inferior_event_token
);
143 /* When set, stop the 'step' command if we enter a function which has
144 no line number information. The normal behavior is that we step
145 over such function. */
146 int step_stop_if_no_debug
= 0;
148 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
149 struct cmd_list_element
*c
, const char *value
)
151 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
154 /* In asynchronous mode, but simulating synchronous execution. */
156 int sync_execution
= 0;
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 means expecting a trace trap
391 and should stop the inferior and return silently when it happens. */
395 /* Nonzero after stop if current stack frame should be printed. */
397 static int stop_print_frame
;
399 /* This is a cached copy of the pid/waitstatus of the last event
400 returned by target_wait()/deprecated_target_wait_hook(). This
401 information is returned by get_last_target_status(). */
402 static ptid_t target_last_wait_ptid
;
403 static struct target_waitstatus target_last_waitstatus
;
405 static void context_switch (ptid_t ptid
);
407 void init_thread_stepping_state (struct thread_info
*tss
);
409 static const char follow_fork_mode_child
[] = "child";
410 static const char follow_fork_mode_parent
[] = "parent";
412 static const char *const follow_fork_mode_kind_names
[] = {
413 follow_fork_mode_child
,
414 follow_fork_mode_parent
,
418 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
420 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
421 struct cmd_list_element
*c
, const char *value
)
423 fprintf_filtered (file
,
424 _("Debugger response to a program "
425 "call of fork or vfork is \"%s\".\n"),
430 /* Handle changes to the inferior list based on the type of fork,
431 which process is being followed, and whether the other process
432 should be detached. On entry inferior_ptid must be the ptid of
433 the fork parent. At return inferior_ptid is the ptid of the
434 followed inferior. */
437 follow_fork_inferior (int follow_child
, int detach_fork
)
440 ptid_t parent_ptid
, child_ptid
;
442 has_vforked
= (inferior_thread ()->pending_follow
.kind
443 == TARGET_WAITKIND_VFORKED
);
444 parent_ptid
= inferior_ptid
;
445 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
448 && !non_stop
/* Non-stop always resumes both branches. */
449 && (!target_is_async_p () || sync_execution
)
450 && !(follow_child
|| detach_fork
|| sched_multi
))
452 /* The parent stays blocked inside the vfork syscall until the
453 child execs or exits. If we don't let the child run, then
454 the parent stays blocked. If we're telling the parent to run
455 in the foreground, the user will not be able to ctrl-c to get
456 back the terminal, effectively hanging the debug session. */
457 fprintf_filtered (gdb_stderr
, _("\
458 Can not resume the parent process over vfork in the foreground while\n\
459 holding the child stopped. Try \"set detach-on-fork\" or \
460 \"set schedule-multiple\".\n"));
461 /* FIXME output string > 80 columns. */
467 /* Detach new forked process? */
470 struct cleanup
*old_chain
;
472 /* Before detaching from the child, remove all breakpoints
473 from it. If we forked, then this has already been taken
474 care of by infrun.c. If we vforked however, any
475 breakpoint inserted in the parent is visible in the
476 child, even those added while stopped in a vfork
477 catchpoint. This will remove the breakpoints from the
478 parent also, but they'll be reinserted below. */
481 /* Keep breakpoints list in sync. */
482 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
485 if (info_verbose
|| debug_infrun
)
487 /* Ensure that we have a process ptid. */
488 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
490 target_terminal_ours_for_output ();
491 fprintf_filtered (gdb_stdlog
,
492 _("Detaching after %s from child %s.\n"),
493 has_vforked
? "vfork" : "fork",
494 target_pid_to_str (process_ptid
));
499 struct inferior
*parent_inf
, *child_inf
;
500 struct cleanup
*old_chain
;
502 /* Add process to GDB's tables. */
503 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
505 parent_inf
= current_inferior ();
506 child_inf
->attach_flag
= parent_inf
->attach_flag
;
507 copy_terminal_info (child_inf
, parent_inf
);
508 child_inf
->gdbarch
= parent_inf
->gdbarch
;
509 copy_inferior_target_desc_info (child_inf
, parent_inf
);
511 old_chain
= save_inferior_ptid ();
512 save_current_program_space ();
514 inferior_ptid
= child_ptid
;
515 add_thread (inferior_ptid
);
516 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
518 /* If this is a vfork child, then the address-space is
519 shared with the parent. */
522 child_inf
->pspace
= parent_inf
->pspace
;
523 child_inf
->aspace
= parent_inf
->aspace
;
525 /* The parent will be frozen until the child is done
526 with the shared region. Keep track of the
528 child_inf
->vfork_parent
= parent_inf
;
529 child_inf
->pending_detach
= 0;
530 parent_inf
->vfork_child
= child_inf
;
531 parent_inf
->pending_detach
= 0;
535 child_inf
->aspace
= new_address_space ();
536 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
537 child_inf
->removable
= 1;
538 set_current_program_space (child_inf
->pspace
);
539 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
541 /* Let the shared library layer (e.g., solib-svr4) learn
542 about this new process, relocate the cloned exec, pull
543 in shared libraries, and install the solib event
544 breakpoint. If a "cloned-VM" event was propagated
545 better throughout the core, this wouldn't be
547 solib_create_inferior_hook (0);
550 do_cleanups (old_chain
);
555 struct inferior
*parent_inf
;
557 parent_inf
= current_inferior ();
559 /* If we detached from the child, then we have to be careful
560 to not insert breakpoints in the parent until the child
561 is done with the shared memory region. However, if we're
562 staying attached to the child, then we can and should
563 insert breakpoints, so that we can debug it. A
564 subsequent child exec or exit is enough to know when does
565 the child stops using the parent's address space. */
566 parent_inf
->waiting_for_vfork_done
= detach_fork
;
567 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
572 /* Follow the child. */
573 struct inferior
*parent_inf
, *child_inf
;
574 struct program_space
*parent_pspace
;
576 if (info_verbose
|| debug_infrun
)
578 target_terminal_ours_for_output ();
579 fprintf_filtered (gdb_stdlog
,
580 _("Attaching after %s %s to child %s.\n"),
581 target_pid_to_str (parent_ptid
),
582 has_vforked
? "vfork" : "fork",
583 target_pid_to_str (child_ptid
));
586 /* Add the new inferior first, so that the target_detach below
587 doesn't unpush the target. */
589 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
591 parent_inf
= current_inferior ();
592 child_inf
->attach_flag
= parent_inf
->attach_flag
;
593 copy_terminal_info (child_inf
, parent_inf
);
594 child_inf
->gdbarch
= parent_inf
->gdbarch
;
595 copy_inferior_target_desc_info (child_inf
, parent_inf
);
597 parent_pspace
= parent_inf
->pspace
;
599 /* If we're vforking, we want to hold on to the parent until the
600 child exits or execs. At child exec or exit time we can
601 remove the old breakpoints from the parent and detach or
602 resume debugging it. Otherwise, detach the parent now; we'll
603 want to reuse it's program/address spaces, but we can't set
604 them to the child before removing breakpoints from the
605 parent, otherwise, the breakpoints module could decide to
606 remove breakpoints from the wrong process (since they'd be
607 assigned to the same address space). */
611 gdb_assert (child_inf
->vfork_parent
== NULL
);
612 gdb_assert (parent_inf
->vfork_child
== NULL
);
613 child_inf
->vfork_parent
= parent_inf
;
614 child_inf
->pending_detach
= 0;
615 parent_inf
->vfork_child
= child_inf
;
616 parent_inf
->pending_detach
= detach_fork
;
617 parent_inf
->waiting_for_vfork_done
= 0;
619 else if (detach_fork
)
621 if (info_verbose
|| debug_infrun
)
623 /* Ensure that we have a process ptid. */
624 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
626 target_terminal_ours_for_output ();
627 fprintf_filtered (gdb_stdlog
,
628 _("Detaching after fork from "
630 target_pid_to_str (process_ptid
));
633 target_detach (NULL
, 0);
636 /* Note that the detach above makes PARENT_INF dangling. */
638 /* Add the child thread to the appropriate lists, and switch to
639 this new thread, before cloning the program space, and
640 informing the solib layer about this new process. */
642 inferior_ptid
= child_ptid
;
643 add_thread (inferior_ptid
);
645 /* If this is a vfork child, then the address-space is shared
646 with the parent. If we detached from the parent, then we can
647 reuse the parent's program/address spaces. */
648 if (has_vforked
|| detach_fork
)
650 child_inf
->pspace
= parent_pspace
;
651 child_inf
->aspace
= child_inf
->pspace
->aspace
;
655 child_inf
->aspace
= new_address_space ();
656 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
657 child_inf
->removable
= 1;
658 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
659 set_current_program_space (child_inf
->pspace
);
660 clone_program_space (child_inf
->pspace
, parent_pspace
);
662 /* Let the shared library layer (e.g., solib-svr4) learn
663 about this new process, relocate the cloned exec, pull in
664 shared libraries, and install the solib event breakpoint.
665 If a "cloned-VM" event was propagated better throughout
666 the core, this wouldn't be required. */
667 solib_create_inferior_hook (0);
671 return target_follow_fork (follow_child
, detach_fork
);
674 /* Tell the target to follow the fork we're stopped at. Returns true
675 if the inferior should be resumed; false, if the target for some
676 reason decided it's best not to resume. */
681 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
682 int should_resume
= 1;
683 struct thread_info
*tp
;
685 /* Copy user stepping state to the new inferior thread. FIXME: the
686 followed fork child thread should have a copy of most of the
687 parent thread structure's run control related fields, not just these.
688 Initialized to avoid "may be used uninitialized" warnings from gcc. */
689 struct breakpoint
*step_resume_breakpoint
= NULL
;
690 struct breakpoint
*exception_resume_breakpoint
= NULL
;
691 CORE_ADDR step_range_start
= 0;
692 CORE_ADDR step_range_end
= 0;
693 struct frame_id step_frame_id
= { 0 };
694 struct interp
*command_interp
= NULL
;
699 struct target_waitstatus wait_status
;
701 /* Get the last target status returned by target_wait(). */
702 get_last_target_status (&wait_ptid
, &wait_status
);
704 /* If not stopped at a fork event, then there's nothing else to
706 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
707 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
710 /* Check if we switched over from WAIT_PTID, since the event was
712 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
713 && !ptid_equal (inferior_ptid
, wait_ptid
))
715 /* We did. Switch back to WAIT_PTID thread, to tell the
716 target to follow it (in either direction). We'll
717 afterwards refuse to resume, and inform the user what
719 switch_to_thread (wait_ptid
);
724 tp
= inferior_thread ();
726 /* If there were any forks/vforks that were caught and are now to be
727 followed, then do so now. */
728 switch (tp
->pending_follow
.kind
)
730 case TARGET_WAITKIND_FORKED
:
731 case TARGET_WAITKIND_VFORKED
:
733 ptid_t parent
, child
;
735 /* If the user did a next/step, etc, over a fork call,
736 preserve the stepping state in the fork child. */
737 if (follow_child
&& should_resume
)
739 step_resume_breakpoint
= clone_momentary_breakpoint
740 (tp
->control
.step_resume_breakpoint
);
741 step_range_start
= tp
->control
.step_range_start
;
742 step_range_end
= tp
->control
.step_range_end
;
743 step_frame_id
= tp
->control
.step_frame_id
;
744 exception_resume_breakpoint
745 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
746 command_interp
= tp
->control
.command_interp
;
748 /* For now, delete the parent's sr breakpoint, otherwise,
749 parent/child sr breakpoints are considered duplicates,
750 and the child version will not be installed. Remove
751 this when the breakpoints module becomes aware of
752 inferiors and address spaces. */
753 delete_step_resume_breakpoint (tp
);
754 tp
->control
.step_range_start
= 0;
755 tp
->control
.step_range_end
= 0;
756 tp
->control
.step_frame_id
= null_frame_id
;
757 delete_exception_resume_breakpoint (tp
);
758 tp
->control
.command_interp
= NULL
;
761 parent
= inferior_ptid
;
762 child
= tp
->pending_follow
.value
.related_pid
;
764 /* Set up inferior(s) as specified by the caller, and tell the
765 target to do whatever is necessary to follow either parent
767 if (follow_fork_inferior (follow_child
, detach_fork
))
769 /* Target refused to follow, or there's some other reason
770 we shouldn't resume. */
775 /* This pending follow fork event is now handled, one way
776 or another. The previous selected thread may be gone
777 from the lists by now, but if it is still around, need
778 to clear the pending follow request. */
779 tp
= find_thread_ptid (parent
);
781 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
783 /* This makes sure we don't try to apply the "Switched
784 over from WAIT_PID" logic above. */
785 nullify_last_target_wait_ptid ();
787 /* If we followed the child, switch to it... */
790 switch_to_thread (child
);
792 /* ... and preserve the stepping state, in case the
793 user was stepping over the fork call. */
796 tp
= inferior_thread ();
797 tp
->control
.step_resume_breakpoint
798 = step_resume_breakpoint
;
799 tp
->control
.step_range_start
= step_range_start
;
800 tp
->control
.step_range_end
= step_range_end
;
801 tp
->control
.step_frame_id
= step_frame_id
;
802 tp
->control
.exception_resume_breakpoint
803 = exception_resume_breakpoint
;
804 tp
->control
.command_interp
= command_interp
;
808 /* If we get here, it was because we're trying to
809 resume from a fork catchpoint, but, the user
810 has switched threads away from the thread that
811 forked. In that case, the resume command
812 issued is most likely not applicable to the
813 child, so just warn, and refuse to resume. */
814 warning (_("Not resuming: switched threads "
815 "before following fork child."));
818 /* Reset breakpoints in the child as appropriate. */
819 follow_inferior_reset_breakpoints ();
822 switch_to_thread (parent
);
826 case TARGET_WAITKIND_SPURIOUS
:
827 /* Nothing to follow. */
830 internal_error (__FILE__
, __LINE__
,
831 "Unexpected pending_follow.kind %d\n",
832 tp
->pending_follow
.kind
);
836 return should_resume
;
840 follow_inferior_reset_breakpoints (void)
842 struct thread_info
*tp
= inferior_thread ();
844 /* Was there a step_resume breakpoint? (There was if the user
845 did a "next" at the fork() call.) If so, explicitly reset its
846 thread number. Cloned step_resume breakpoints are disabled on
847 creation, so enable it here now that it is associated with the
850 step_resumes are a form of bp that are made to be per-thread.
851 Since we created the step_resume bp when the parent process
852 was being debugged, and now are switching to the child process,
853 from the breakpoint package's viewpoint, that's a switch of
854 "threads". We must update the bp's notion of which thread
855 it is for, or it'll be ignored when it triggers. */
857 if (tp
->control
.step_resume_breakpoint
)
859 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
860 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
863 /* Treat exception_resume breakpoints like step_resume breakpoints. */
864 if (tp
->control
.exception_resume_breakpoint
)
866 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
867 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
870 /* Reinsert all breakpoints in the child. The user may have set
871 breakpoints after catching the fork, in which case those
872 were never set in the child, but only in the parent. This makes
873 sure the inserted breakpoints match the breakpoint list. */
875 breakpoint_re_set ();
876 insert_breakpoints ();
879 /* The child has exited or execed: resume threads of the parent the
880 user wanted to be executing. */
883 proceed_after_vfork_done (struct thread_info
*thread
,
886 int pid
= * (int *) arg
;
888 if (ptid_get_pid (thread
->ptid
) == pid
889 && is_running (thread
->ptid
)
890 && !is_executing (thread
->ptid
)
891 && !thread
->stop_requested
892 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
895 fprintf_unfiltered (gdb_stdlog
,
896 "infrun: resuming vfork parent thread %s\n",
897 target_pid_to_str (thread
->ptid
));
899 switch_to_thread (thread
->ptid
);
900 clear_proceed_status (0);
901 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
907 /* Called whenever we notice an exec or exit event, to handle
908 detaching or resuming a vfork parent. */
911 handle_vfork_child_exec_or_exit (int exec
)
913 struct inferior
*inf
= current_inferior ();
915 if (inf
->vfork_parent
)
917 int resume_parent
= -1;
919 /* This exec or exit marks the end of the shared memory region
920 between the parent and the child. If the user wanted to
921 detach from the parent, now is the time. */
923 if (inf
->vfork_parent
->pending_detach
)
925 struct thread_info
*tp
;
926 struct cleanup
*old_chain
;
927 struct program_space
*pspace
;
928 struct address_space
*aspace
;
930 /* follow-fork child, detach-on-fork on. */
932 inf
->vfork_parent
->pending_detach
= 0;
936 /* If we're handling a child exit, then inferior_ptid
937 points at the inferior's pid, not to a thread. */
938 old_chain
= save_inferior_ptid ();
939 save_current_program_space ();
940 save_current_inferior ();
943 old_chain
= save_current_space_and_thread ();
945 /* We're letting loose of the parent. */
946 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
947 switch_to_thread (tp
->ptid
);
949 /* We're about to detach from the parent, which implicitly
950 removes breakpoints from its address space. There's a
951 catch here: we want to reuse the spaces for the child,
952 but, parent/child are still sharing the pspace at this
953 point, although the exec in reality makes the kernel give
954 the child a fresh set of new pages. The problem here is
955 that the breakpoints module being unaware of this, would
956 likely chose the child process to write to the parent
957 address space. Swapping the child temporarily away from
958 the spaces has the desired effect. Yes, this is "sort
961 pspace
= inf
->pspace
;
962 aspace
= inf
->aspace
;
966 if (debug_infrun
|| info_verbose
)
968 target_terminal_ours_for_output ();
972 fprintf_filtered (gdb_stdlog
,
973 _("Detaching vfork parent process "
974 "%d after child exec.\n"),
975 inf
->vfork_parent
->pid
);
979 fprintf_filtered (gdb_stdlog
,
980 _("Detaching vfork parent process "
981 "%d after child exit.\n"),
982 inf
->vfork_parent
->pid
);
986 target_detach (NULL
, 0);
989 inf
->pspace
= pspace
;
990 inf
->aspace
= aspace
;
992 do_cleanups (old_chain
);
996 /* We're staying attached to the parent, so, really give the
997 child a new address space. */
998 inf
->pspace
= add_program_space (maybe_new_address_space ());
999 inf
->aspace
= inf
->pspace
->aspace
;
1001 set_current_program_space (inf
->pspace
);
1003 resume_parent
= inf
->vfork_parent
->pid
;
1005 /* Break the bonds. */
1006 inf
->vfork_parent
->vfork_child
= NULL
;
1010 struct cleanup
*old_chain
;
1011 struct program_space
*pspace
;
1013 /* If this is a vfork child exiting, then the pspace and
1014 aspaces were shared with the parent. Since we're
1015 reporting the process exit, we'll be mourning all that is
1016 found in the address space, and switching to null_ptid,
1017 preparing to start a new inferior. But, since we don't
1018 want to clobber the parent's address/program spaces, we
1019 go ahead and create a new one for this exiting
1022 /* Switch to null_ptid, so that clone_program_space doesn't want
1023 to read the selected frame of a dead process. */
1024 old_chain
= save_inferior_ptid ();
1025 inferior_ptid
= null_ptid
;
1027 /* This inferior is dead, so avoid giving the breakpoints
1028 module the option to write through to it (cloning a
1029 program space resets breakpoints). */
1032 pspace
= add_program_space (maybe_new_address_space ());
1033 set_current_program_space (pspace
);
1035 inf
->symfile_flags
= SYMFILE_NO_READ
;
1036 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1037 inf
->pspace
= pspace
;
1038 inf
->aspace
= pspace
->aspace
;
1040 /* Put back inferior_ptid. We'll continue mourning this
1042 do_cleanups (old_chain
);
1044 resume_parent
= inf
->vfork_parent
->pid
;
1045 /* Break the bonds. */
1046 inf
->vfork_parent
->vfork_child
= NULL
;
1049 inf
->vfork_parent
= NULL
;
1051 gdb_assert (current_program_space
== inf
->pspace
);
1053 if (non_stop
&& resume_parent
!= -1)
1055 /* If the user wanted the parent to be running, let it go
1057 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1060 fprintf_unfiltered (gdb_stdlog
,
1061 "infrun: resuming vfork parent process %d\n",
1064 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1066 do_cleanups (old_chain
);
1071 /* Enum strings for "set|show follow-exec-mode". */
1073 static const char follow_exec_mode_new
[] = "new";
1074 static const char follow_exec_mode_same
[] = "same";
1075 static const char *const follow_exec_mode_names
[] =
1077 follow_exec_mode_new
,
1078 follow_exec_mode_same
,
1082 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1084 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1085 struct cmd_list_element
*c
, const char *value
)
1087 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1090 /* EXECD_PATHNAME is assumed to be non-NULL. */
1093 follow_exec (ptid_t ptid
, char *execd_pathname
)
1095 struct thread_info
*th
, *tmp
;
1096 struct inferior
*inf
= current_inferior ();
1097 int pid
= ptid_get_pid (ptid
);
1098 ptid_t process_ptid
;
1100 /* This is an exec event that we actually wish to pay attention to.
1101 Refresh our symbol table to the newly exec'd program, remove any
1102 momentary bp's, etc.
1104 If there are breakpoints, they aren't really inserted now,
1105 since the exec() transformed our inferior into a fresh set
1108 We want to preserve symbolic breakpoints on the list, since
1109 we have hopes that they can be reset after the new a.out's
1110 symbol table is read.
1112 However, any "raw" breakpoints must be removed from the list
1113 (e.g., the solib bp's), since their address is probably invalid
1116 And, we DON'T want to call delete_breakpoints() here, since
1117 that may write the bp's "shadow contents" (the instruction
1118 value that was overwritten witha TRAP instruction). Since
1119 we now have a new a.out, those shadow contents aren't valid. */
1121 mark_breakpoints_out ();
1123 /* The target reports the exec event to the main thread, even if
1124 some other thread does the exec, and even if the main thread was
1125 stopped or already gone. We may still have non-leader threads of
1126 the process on our list. E.g., on targets that don't have thread
1127 exit events (like remote); or on native Linux in non-stop mode if
1128 there were only two threads in the inferior and the non-leader
1129 one is the one that execs (and nothing forces an update of the
1130 thread list up to here). When debugging remotely, it's best to
1131 avoid extra traffic, when possible, so avoid syncing the thread
1132 list with the target, and instead go ahead and delete all threads
1133 of the process but one that reported the event. Note this must
1134 be done before calling update_breakpoints_after_exec, as
1135 otherwise clearing the threads' resources would reference stale
1136 thread breakpoints -- it may have been one of these threads that
1137 stepped across the exec. We could just clear their stepping
1138 states, but as long as we're iterating, might as well delete
1139 them. Deleting them now rather than at the next user-visible
1140 stop provides a nicer sequence of events for user and MI
1142 ALL_THREADS_SAFE (th
, tmp
)
1143 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1144 delete_thread (th
->ptid
);
1146 /* We also need to clear any left over stale state for the
1147 leader/event thread. E.g., if there was any step-resume
1148 breakpoint or similar, it's gone now. We cannot truly
1149 step-to-next statement through an exec(). */
1150 th
= inferior_thread ();
1151 th
->control
.step_resume_breakpoint
= NULL
;
1152 th
->control
.exception_resume_breakpoint
= NULL
;
1153 th
->control
.single_step_breakpoints
= NULL
;
1154 th
->control
.step_range_start
= 0;
1155 th
->control
.step_range_end
= 0;
1157 /* The user may have had the main thread held stopped in the
1158 previous image (e.g., schedlock on, or non-stop). Release
1160 th
->stop_requested
= 0;
1162 update_breakpoints_after_exec ();
1164 /* What is this a.out's name? */
1165 process_ptid
= pid_to_ptid (pid
);
1166 printf_unfiltered (_("%s is executing new program: %s\n"),
1167 target_pid_to_str (process_ptid
),
1170 /* We've followed the inferior through an exec. Therefore, the
1171 inferior has essentially been killed & reborn. */
1173 gdb_flush (gdb_stdout
);
1175 breakpoint_init_inferior (inf_execd
);
1177 if (*gdb_sysroot
!= '\0')
1179 char *name
= exec_file_find (execd_pathname
, NULL
);
1181 execd_pathname
= (char *) alloca (strlen (name
) + 1);
1182 strcpy (execd_pathname
, name
);
1186 /* Reset the shared library package. This ensures that we get a
1187 shlib event when the child reaches "_start", at which point the
1188 dld will have had a chance to initialize the child. */
1189 /* Also, loading a symbol file below may trigger symbol lookups, and
1190 we don't want those to be satisfied by the libraries of the
1191 previous incarnation of this process. */
1192 no_shared_libraries (NULL
, 0);
1194 if (follow_exec_mode_string
== follow_exec_mode_new
)
1196 /* The user wants to keep the old inferior and program spaces
1197 around. Create a new fresh one, and switch to it. */
1199 /* Do exit processing for the original inferior before adding
1200 the new inferior so we don't have two active inferiors with
1201 the same ptid, which can confuse find_inferior_ptid. */
1202 exit_inferior_num_silent (current_inferior ()->num
);
1204 inf
= add_inferior_with_spaces ();
1206 target_follow_exec (inf
, execd_pathname
);
1208 set_current_inferior (inf
);
1209 set_current_program_space (inf
->pspace
);
1214 /* The old description may no longer be fit for the new image.
1215 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1216 old description; we'll read a new one below. No need to do
1217 this on "follow-exec-mode new", as the old inferior stays
1218 around (its description is later cleared/refetched on
1220 target_clear_description ();
1223 gdb_assert (current_program_space
== inf
->pspace
);
1225 /* That a.out is now the one to use. */
1226 exec_file_attach (execd_pathname
, 0);
1228 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1229 (Position Independent Executable) main symbol file will get applied by
1230 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1231 the breakpoints with the zero displacement. */
1233 symbol_file_add (execd_pathname
,
1235 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
1238 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
1239 set_initial_language ();
1241 /* If the target can specify a description, read it. Must do this
1242 after flipping to the new executable (because the target supplied
1243 description must be compatible with the executable's
1244 architecture, and the old executable may e.g., be 32-bit, while
1245 the new one 64-bit), and before anything involving memory or
1247 target_find_description ();
1249 solib_create_inferior_hook (0);
1251 jit_inferior_created_hook ();
1253 breakpoint_re_set ();
1255 /* Reinsert all breakpoints. (Those which were symbolic have
1256 been reset to the proper address in the new a.out, thanks
1257 to symbol_file_command...). */
1258 insert_breakpoints ();
1260 /* The next resume of this inferior should bring it to the shlib
1261 startup breakpoints. (If the user had also set bp's on
1262 "main" from the old (parent) process, then they'll auto-
1263 matically get reset there in the new process.). */
1266 /* The queue of threads that need to do a step-over operation to get
1267 past e.g., a breakpoint. What technique is used to step over the
1268 breakpoint/watchpoint does not matter -- all threads end up in the
1269 same queue, to maintain rough temporal order of execution, in order
1270 to avoid starvation, otherwise, we could e.g., find ourselves
1271 constantly stepping the same couple threads past their breakpoints
1272 over and over, if the single-step finish fast enough. */
1273 struct thread_info
*step_over_queue_head
;
1275 /* Bit flags indicating what the thread needs to step over. */
1279 /* Step over a breakpoint. */
1280 STEP_OVER_BREAKPOINT
= 1,
1282 /* Step past a non-continuable watchpoint, in order to let the
1283 instruction execute so we can evaluate the watchpoint
1285 STEP_OVER_WATCHPOINT
= 2
1288 /* Info about an instruction that is being stepped over. */
1290 struct step_over_info
1292 /* If we're stepping past a breakpoint, this is the address space
1293 and address of the instruction the breakpoint is set at. We'll
1294 skip inserting all breakpoints here. Valid iff ASPACE is
1296 struct address_space
*aspace
;
1299 /* The instruction being stepped over triggers a nonsteppable
1300 watchpoint. If true, we'll skip inserting watchpoints. */
1301 int nonsteppable_watchpoint_p
;
1304 /* The step-over info of the location that is being stepped over.
1306 Note that with async/breakpoint always-inserted mode, a user might
1307 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1308 being stepped over. As setting a new breakpoint inserts all
1309 breakpoints, we need to make sure the breakpoint being stepped over
1310 isn't inserted then. We do that by only clearing the step-over
1311 info when the step-over is actually finished (or aborted).
1313 Presently GDB can only step over one breakpoint at any given time.
1314 Given threads that can't run code in the same address space as the
1315 breakpoint's can't really miss the breakpoint, GDB could be taught
1316 to step-over at most one breakpoint per address space (so this info
1317 could move to the address space object if/when GDB is extended).
1318 The set of breakpoints being stepped over will normally be much
1319 smaller than the set of all breakpoints, so a flag in the
1320 breakpoint location structure would be wasteful. A separate list
1321 also saves complexity and run-time, as otherwise we'd have to go
1322 through all breakpoint locations clearing their flag whenever we
1323 start a new sequence. Similar considerations weigh against storing
1324 this info in the thread object. Plus, not all step overs actually
1325 have breakpoint locations -- e.g., stepping past a single-step
1326 breakpoint, or stepping to complete a non-continuable
1328 static struct step_over_info step_over_info
;
1330 /* Record the address of the breakpoint/instruction we're currently
1334 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1335 int nonsteppable_watchpoint_p
)
1337 step_over_info
.aspace
= aspace
;
1338 step_over_info
.address
= address
;
1339 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1342 /* Called when we're not longer stepping over a breakpoint / an
1343 instruction, so all breakpoints are free to be (re)inserted. */
1346 clear_step_over_info (void)
1349 fprintf_unfiltered (gdb_stdlog
,
1350 "infrun: clear_step_over_info\n");
1351 step_over_info
.aspace
= NULL
;
1352 step_over_info
.address
= 0;
1353 step_over_info
.nonsteppable_watchpoint_p
= 0;
1359 stepping_past_instruction_at (struct address_space
*aspace
,
1362 return (step_over_info
.aspace
!= NULL
1363 && breakpoint_address_match (aspace
, address
,
1364 step_over_info
.aspace
,
1365 step_over_info
.address
));
1371 stepping_past_nonsteppable_watchpoint (void)
1373 return step_over_info
.nonsteppable_watchpoint_p
;
1376 /* Returns true if step-over info is valid. */
1379 step_over_info_valid_p (void)
1381 return (step_over_info
.aspace
!= NULL
1382 || stepping_past_nonsteppable_watchpoint ());
1386 /* Displaced stepping. */
1388 /* In non-stop debugging mode, we must take special care to manage
1389 breakpoints properly; in particular, the traditional strategy for
1390 stepping a thread past a breakpoint it has hit is unsuitable.
1391 'Displaced stepping' is a tactic for stepping one thread past a
1392 breakpoint it has hit while ensuring that other threads running
1393 concurrently will hit the breakpoint as they should.
1395 The traditional way to step a thread T off a breakpoint in a
1396 multi-threaded program in all-stop mode is as follows:
1398 a0) Initially, all threads are stopped, and breakpoints are not
1400 a1) We single-step T, leaving breakpoints uninserted.
1401 a2) We insert breakpoints, and resume all threads.
1403 In non-stop debugging, however, this strategy is unsuitable: we
1404 don't want to have to stop all threads in the system in order to
1405 continue or step T past a breakpoint. Instead, we use displaced
1408 n0) Initially, T is stopped, other threads are running, and
1409 breakpoints are inserted.
1410 n1) We copy the instruction "under" the breakpoint to a separate
1411 location, outside the main code stream, making any adjustments
1412 to the instruction, register, and memory state as directed by
1414 n2) We single-step T over the instruction at its new location.
1415 n3) We adjust the resulting register and memory state as directed
1416 by T's architecture. This includes resetting T's PC to point
1417 back into the main instruction stream.
1420 This approach depends on the following gdbarch methods:
1422 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1423 indicate where to copy the instruction, and how much space must
1424 be reserved there. We use these in step n1.
1426 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1427 address, and makes any necessary adjustments to the instruction,
1428 register contents, and memory. We use this in step n1.
1430 - gdbarch_displaced_step_fixup adjusts registers and memory after
1431 we have successfuly single-stepped the instruction, to yield the
1432 same effect the instruction would have had if we had executed it
1433 at its original address. We use this in step n3.
1435 - gdbarch_displaced_step_free_closure provides cleanup.
1437 The gdbarch_displaced_step_copy_insn and
1438 gdbarch_displaced_step_fixup functions must be written so that
1439 copying an instruction with gdbarch_displaced_step_copy_insn,
1440 single-stepping across the copied instruction, and then applying
1441 gdbarch_displaced_insn_fixup should have the same effects on the
1442 thread's memory and registers as stepping the instruction in place
1443 would have. Exactly which responsibilities fall to the copy and
1444 which fall to the fixup is up to the author of those functions.
1446 See the comments in gdbarch.sh for details.
1448 Note that displaced stepping and software single-step cannot
1449 currently be used in combination, although with some care I think
1450 they could be made to. Software single-step works by placing
1451 breakpoints on all possible subsequent instructions; if the
1452 displaced instruction is a PC-relative jump, those breakpoints
1453 could fall in very strange places --- on pages that aren't
1454 executable, or at addresses that are not proper instruction
1455 boundaries. (We do generally let other threads run while we wait
1456 to hit the software single-step breakpoint, and they might
1457 encounter such a corrupted instruction.) One way to work around
1458 this would be to have gdbarch_displaced_step_copy_insn fully
1459 simulate the effect of PC-relative instructions (and return NULL)
1460 on architectures that use software single-stepping.
1462 In non-stop mode, we can have independent and simultaneous step
1463 requests, so more than one thread may need to simultaneously step
1464 over a breakpoint. The current implementation assumes there is
1465 only one scratch space per process. In this case, we have to
1466 serialize access to the scratch space. If thread A wants to step
1467 over a breakpoint, but we are currently waiting for some other
1468 thread to complete a displaced step, we leave thread A stopped and
1469 place it in the displaced_step_request_queue. Whenever a displaced
1470 step finishes, we pick the next thread in the queue and start a new
1471 displaced step operation on it. See displaced_step_prepare and
1472 displaced_step_fixup for details. */
1474 /* Per-inferior displaced stepping state. */
1475 struct displaced_step_inferior_state
1477 /* Pointer to next in linked list. */
1478 struct displaced_step_inferior_state
*next
;
1480 /* The process this displaced step state refers to. */
1483 /* True if preparing a displaced step ever failed. If so, we won't
1484 try displaced stepping for this inferior again. */
1487 /* If this is not null_ptid, this is the thread carrying out a
1488 displaced single-step in process PID. This thread's state will
1489 require fixing up once it has completed its step. */
1492 /* The architecture the thread had when we stepped it. */
1493 struct gdbarch
*step_gdbarch
;
1495 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1496 for post-step cleanup. */
1497 struct displaced_step_closure
*step_closure
;
1499 /* The address of the original instruction, and the copy we
1501 CORE_ADDR step_original
, step_copy
;
1503 /* Saved contents of copy area. */
1504 gdb_byte
*step_saved_copy
;
1507 /* The list of states of processes involved in displaced stepping
1509 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1511 /* Get the displaced stepping state of process PID. */
1513 static struct displaced_step_inferior_state
*
1514 get_displaced_stepping_state (int pid
)
1516 struct displaced_step_inferior_state
*state
;
1518 for (state
= displaced_step_inferior_states
;
1520 state
= state
->next
)
1521 if (state
->pid
== pid
)
1527 /* Returns true if any inferior has a thread doing a displaced
1531 displaced_step_in_progress_any_inferior (void)
1533 struct displaced_step_inferior_state
*state
;
1535 for (state
= displaced_step_inferior_states
;
1537 state
= state
->next
)
1538 if (!ptid_equal (state
->step_ptid
, null_ptid
))
1544 /* Return true if process PID has a thread doing a displaced step. */
1547 displaced_step_in_progress (int pid
)
1549 struct displaced_step_inferior_state
*displaced
;
1551 displaced
= get_displaced_stepping_state (pid
);
1552 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1558 /* Add a new displaced stepping state for process PID to the displaced
1559 stepping state list, or return a pointer to an already existing
1560 entry, if it already exists. Never returns NULL. */
1562 static struct displaced_step_inferior_state
*
1563 add_displaced_stepping_state (int pid
)
1565 struct displaced_step_inferior_state
*state
;
1567 for (state
= displaced_step_inferior_states
;
1569 state
= state
->next
)
1570 if (state
->pid
== pid
)
1573 state
= XCNEW (struct displaced_step_inferior_state
);
1575 state
->next
= displaced_step_inferior_states
;
1576 displaced_step_inferior_states
= state
;
1581 /* If inferior is in displaced stepping, and ADDR equals to starting address
1582 of copy area, return corresponding displaced_step_closure. Otherwise,
1585 struct displaced_step_closure
*
1586 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1588 struct displaced_step_inferior_state
*displaced
1589 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1591 /* If checking the mode of displaced instruction in copy area. */
1592 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1593 && (displaced
->step_copy
== addr
))
1594 return displaced
->step_closure
;
1599 /* Remove the displaced stepping state of process PID. */
1602 remove_displaced_stepping_state (int pid
)
1604 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1606 gdb_assert (pid
!= 0);
1608 it
= displaced_step_inferior_states
;
1609 prev_next_p
= &displaced_step_inferior_states
;
1614 *prev_next_p
= it
->next
;
1619 prev_next_p
= &it
->next
;
1625 infrun_inferior_exit (struct inferior
*inf
)
1627 remove_displaced_stepping_state (inf
->pid
);
1630 /* If ON, and the architecture supports it, GDB will use displaced
1631 stepping to step over breakpoints. If OFF, or if the architecture
1632 doesn't support it, GDB will instead use the traditional
1633 hold-and-step approach. If AUTO (which is the default), GDB will
1634 decide which technique to use to step over breakpoints depending on
1635 which of all-stop or non-stop mode is active --- displaced stepping
1636 in non-stop mode; hold-and-step in all-stop mode. */
1638 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1641 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1642 struct cmd_list_element
*c
,
1645 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1646 fprintf_filtered (file
,
1647 _("Debugger's willingness to use displaced stepping "
1648 "to step over breakpoints is %s (currently %s).\n"),
1649 value
, target_is_non_stop_p () ? "on" : "off");
1651 fprintf_filtered (file
,
1652 _("Debugger's willingness to use displaced stepping "
1653 "to step over breakpoints is %s.\n"), value
);
1656 /* Return non-zero if displaced stepping can/should be used to step
1657 over breakpoints of thread TP. */
1660 use_displaced_stepping (struct thread_info
*tp
)
1662 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
1663 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1664 struct displaced_step_inferior_state
*displaced_state
;
1666 displaced_state
= get_displaced_stepping_state (ptid_get_pid (tp
->ptid
));
1668 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1669 && target_is_non_stop_p ())
1670 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1671 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1672 && find_record_target () == NULL
1673 && (displaced_state
== NULL
1674 || !displaced_state
->failed_before
));
1677 /* Clean out any stray displaced stepping state. */
1679 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1681 /* Indicate that there is no cleanup pending. */
1682 displaced
->step_ptid
= null_ptid
;
1684 if (displaced
->step_closure
)
1686 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1687 displaced
->step_closure
);
1688 displaced
->step_closure
= NULL
;
1693 displaced_step_clear_cleanup (void *arg
)
1695 struct displaced_step_inferior_state
*state
1696 = (struct displaced_step_inferior_state
*) arg
;
1698 displaced_step_clear (state
);
1701 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1703 displaced_step_dump_bytes (struct ui_file
*file
,
1704 const gdb_byte
*buf
,
1709 for (i
= 0; i
< len
; i
++)
1710 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1711 fputs_unfiltered ("\n", file
);
1714 /* Prepare to single-step, using displaced stepping.
1716 Note that we cannot use displaced stepping when we have a signal to
1717 deliver. If we have a signal to deliver and an instruction to step
1718 over, then after the step, there will be no indication from the
1719 target whether the thread entered a signal handler or ignored the
1720 signal and stepped over the instruction successfully --- both cases
1721 result in a simple SIGTRAP. In the first case we mustn't do a
1722 fixup, and in the second case we must --- but we can't tell which.
1723 Comments in the code for 'random signals' in handle_inferior_event
1724 explain how we handle this case instead.
1726 Returns 1 if preparing was successful -- this thread is going to be
1727 stepped now; 0 if displaced stepping this thread got queued; or -1
1728 if this instruction can't be displaced stepped. */
1731 displaced_step_prepare_throw (ptid_t ptid
)
1733 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1734 struct thread_info
*tp
= find_thread_ptid (ptid
);
1735 struct regcache
*regcache
= get_thread_regcache (ptid
);
1736 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1737 CORE_ADDR original
, copy
;
1739 struct displaced_step_closure
*closure
;
1740 struct displaced_step_inferior_state
*displaced
;
1743 /* We should never reach this function if the architecture does not
1744 support displaced stepping. */
1745 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1747 /* Nor if the thread isn't meant to step over a breakpoint. */
1748 gdb_assert (tp
->control
.trap_expected
);
1750 /* Disable range stepping while executing in the scratch pad. We
1751 want a single-step even if executing the displaced instruction in
1752 the scratch buffer lands within the stepping range (e.g., a
1754 tp
->control
.may_range_step
= 0;
1756 /* We have to displaced step one thread at a time, as we only have
1757 access to a single scratch space per inferior. */
1759 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1761 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1763 /* Already waiting for a displaced step to finish. Defer this
1764 request and place in queue. */
1766 if (debug_displaced
)
1767 fprintf_unfiltered (gdb_stdlog
,
1768 "displaced: deferring step of %s\n",
1769 target_pid_to_str (ptid
));
1771 thread_step_over_chain_enqueue (tp
);
1776 if (debug_displaced
)
1777 fprintf_unfiltered (gdb_stdlog
,
1778 "displaced: stepping %s now\n",
1779 target_pid_to_str (ptid
));
1782 displaced_step_clear (displaced
);
1784 old_cleanups
= save_inferior_ptid ();
1785 inferior_ptid
= ptid
;
1787 original
= regcache_read_pc (regcache
);
1789 copy
= gdbarch_displaced_step_location (gdbarch
);
1790 len
= gdbarch_max_insn_length (gdbarch
);
1792 /* Save the original contents of the copy area. */
1793 displaced
->step_saved_copy
= (gdb_byte
*) xmalloc (len
);
1794 ignore_cleanups
= make_cleanup (free_current_contents
,
1795 &displaced
->step_saved_copy
);
1796 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1798 throw_error (MEMORY_ERROR
,
1799 _("Error accessing memory address %s (%s) for "
1800 "displaced-stepping scratch space."),
1801 paddress (gdbarch
, copy
), safe_strerror (status
));
1802 if (debug_displaced
)
1804 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1805 paddress (gdbarch
, copy
));
1806 displaced_step_dump_bytes (gdb_stdlog
,
1807 displaced
->step_saved_copy
,
1811 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1812 original
, copy
, regcache
);
1813 if (closure
== NULL
)
1815 /* The architecture doesn't know how or want to displaced step
1816 this instruction or instruction sequence. Fallback to
1817 stepping over the breakpoint in-line. */
1818 do_cleanups (old_cleanups
);
1822 /* Save the information we need to fix things up if the step
1824 displaced
->step_ptid
= ptid
;
1825 displaced
->step_gdbarch
= gdbarch
;
1826 displaced
->step_closure
= closure
;
1827 displaced
->step_original
= original
;
1828 displaced
->step_copy
= copy
;
1830 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1832 /* Resume execution at the copy. */
1833 regcache_write_pc (regcache
, copy
);
1835 discard_cleanups (ignore_cleanups
);
1837 do_cleanups (old_cleanups
);
1839 if (debug_displaced
)
1840 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1841 paddress (gdbarch
, copy
));
1846 /* Wrapper for displaced_step_prepare_throw that disabled further
1847 attempts at displaced stepping if we get a memory error. */
1850 displaced_step_prepare (ptid_t ptid
)
1856 prepared
= displaced_step_prepare_throw (ptid
);
1858 CATCH (ex
, RETURN_MASK_ERROR
)
1860 struct displaced_step_inferior_state
*displaced_state
;
1862 if (ex
.error
!= MEMORY_ERROR
)
1863 throw_exception (ex
);
1867 fprintf_unfiltered (gdb_stdlog
,
1868 "infrun: disabling displaced stepping: %s\n",
1872 /* Be verbose if "set displaced-stepping" is "on", silent if
1874 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1876 warning (_("disabling displaced stepping: %s"),
1880 /* Disable further displaced stepping attempts. */
1882 = get_displaced_stepping_state (ptid_get_pid (ptid
));
1883 displaced_state
->failed_before
= 1;
1891 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1892 const gdb_byte
*myaddr
, int len
)
1894 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1896 inferior_ptid
= ptid
;
1897 write_memory (memaddr
, myaddr
, len
);
1898 do_cleanups (ptid_cleanup
);
1901 /* Restore the contents of the copy area for thread PTID. */
1904 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1907 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1909 write_memory_ptid (ptid
, displaced
->step_copy
,
1910 displaced
->step_saved_copy
, len
);
1911 if (debug_displaced
)
1912 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1913 target_pid_to_str (ptid
),
1914 paddress (displaced
->step_gdbarch
,
1915 displaced
->step_copy
));
1918 /* If we displaced stepped an instruction successfully, adjust
1919 registers and memory to yield the same effect the instruction would
1920 have had if we had executed it at its original address, and return
1921 1. If the instruction didn't complete, relocate the PC and return
1922 -1. If the thread wasn't displaced stepping, return 0. */
1925 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1927 struct cleanup
*old_cleanups
;
1928 struct displaced_step_inferior_state
*displaced
1929 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1932 /* Was any thread of this process doing a displaced step? */
1933 if (displaced
== NULL
)
1936 /* Was this event for the pid we displaced? */
1937 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1938 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1941 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1943 displaced_step_restore (displaced
, displaced
->step_ptid
);
1945 /* Fixup may need to read memory/registers. Switch to the thread
1946 that we're fixing up. Also, target_stopped_by_watchpoint checks
1947 the current thread. */
1948 switch_to_thread (event_ptid
);
1950 /* Did the instruction complete successfully? */
1951 if (signal
== GDB_SIGNAL_TRAP
1952 && !(target_stopped_by_watchpoint ()
1953 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1954 || target_have_steppable_watchpoint
)))
1956 /* Fix up the resulting state. */
1957 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1958 displaced
->step_closure
,
1959 displaced
->step_original
,
1960 displaced
->step_copy
,
1961 get_thread_regcache (displaced
->step_ptid
));
1966 /* Since the instruction didn't complete, all we can do is
1968 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1969 CORE_ADDR pc
= regcache_read_pc (regcache
);
1971 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1972 regcache_write_pc (regcache
, pc
);
1976 do_cleanups (old_cleanups
);
1978 displaced
->step_ptid
= null_ptid
;
1983 /* Data to be passed around while handling an event. This data is
1984 discarded between events. */
1985 struct execution_control_state
1988 /* The thread that got the event, if this was a thread event; NULL
1990 struct thread_info
*event_thread
;
1992 struct target_waitstatus ws
;
1993 int stop_func_filled_in
;
1994 CORE_ADDR stop_func_start
;
1995 CORE_ADDR stop_func_end
;
1996 const char *stop_func_name
;
1999 /* True if the event thread hit the single-step breakpoint of
2000 another thread. Thus the event doesn't cause a stop, the thread
2001 needs to be single-stepped past the single-step breakpoint before
2002 we can switch back to the original stepping thread. */
2003 int hit_singlestep_breakpoint
;
2006 /* Clear ECS and set it to point at TP. */
2009 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
2011 memset (ecs
, 0, sizeof (*ecs
));
2012 ecs
->event_thread
= tp
;
2013 ecs
->ptid
= tp
->ptid
;
2016 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
2017 static void prepare_to_wait (struct execution_control_state
*ecs
);
2018 static int keep_going_stepped_thread (struct thread_info
*tp
);
2019 static int thread_still_needs_step_over (struct thread_info
*tp
);
2020 static void stop_all_threads (void);
2022 /* Are there any pending step-over requests? If so, run all we can
2023 now and return true. Otherwise, return false. */
2026 start_step_over (void)
2028 struct thread_info
*tp
, *next
;
2030 /* Don't start a new step-over if we already have an in-line
2031 step-over operation ongoing. */
2032 if (step_over_info_valid_p ())
2035 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
2037 struct execution_control_state ecss
;
2038 struct execution_control_state
*ecs
= &ecss
;
2039 enum step_over_what step_what
;
2040 int must_be_in_line
;
2042 next
= thread_step_over_chain_next (tp
);
2044 /* If this inferior already has a displaced step in process,
2045 don't start a new one. */
2046 if (displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2049 step_what
= thread_still_needs_step_over (tp
);
2050 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
2051 || ((step_what
& STEP_OVER_BREAKPOINT
)
2052 && !use_displaced_stepping (tp
)));
2054 /* We currently stop all threads of all processes to step-over
2055 in-line. If we need to start a new in-line step-over, let
2056 any pending displaced steps finish first. */
2057 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
2060 thread_step_over_chain_remove (tp
);
2062 if (step_over_queue_head
== NULL
)
2065 fprintf_unfiltered (gdb_stdlog
,
2066 "infrun: step-over queue now empty\n");
2069 if (tp
->control
.trap_expected
2073 internal_error (__FILE__
, __LINE__
,
2074 "[%s] has inconsistent state: "
2075 "trap_expected=%d, resumed=%d, executing=%d\n",
2076 target_pid_to_str (tp
->ptid
),
2077 tp
->control
.trap_expected
,
2083 fprintf_unfiltered (gdb_stdlog
,
2084 "infrun: resuming [%s] for step-over\n",
2085 target_pid_to_str (tp
->ptid
));
2087 /* keep_going_pass_signal skips the step-over if the breakpoint
2088 is no longer inserted. In all-stop, we want to keep looking
2089 for a thread that needs a step-over instead of resuming TP,
2090 because we wouldn't be able to resume anything else until the
2091 target stops again. In non-stop, the resume always resumes
2092 only TP, so it's OK to let the thread resume freely. */
2093 if (!target_is_non_stop_p () && !step_what
)
2096 switch_to_thread (tp
->ptid
);
2097 reset_ecs (ecs
, tp
);
2098 keep_going_pass_signal (ecs
);
2100 if (!ecs
->wait_some_more
)
2101 error (_("Command aborted."));
2103 gdb_assert (tp
->resumed
);
2105 /* If we started a new in-line step-over, we're done. */
2106 if (step_over_info_valid_p ())
2108 gdb_assert (tp
->control
.trap_expected
);
2112 if (!target_is_non_stop_p ())
2114 /* On all-stop, shouldn't have resumed unless we needed a
2116 gdb_assert (tp
->control
.trap_expected
2117 || tp
->step_after_step_resume_breakpoint
);
2119 /* With remote targets (at least), in all-stop, we can't
2120 issue any further remote commands until the program stops
2125 /* Either the thread no longer needed a step-over, or a new
2126 displaced stepping sequence started. Even in the latter
2127 case, continue looking. Maybe we can also start another
2128 displaced step on a thread of other process. */
2134 /* Update global variables holding ptids to hold NEW_PTID if they were
2135 holding OLD_PTID. */
2137 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2139 struct displaced_step_request
*it
;
2140 struct displaced_step_inferior_state
*displaced
;
2142 if (ptid_equal (inferior_ptid
, old_ptid
))
2143 inferior_ptid
= new_ptid
;
2145 for (displaced
= displaced_step_inferior_states
;
2147 displaced
= displaced
->next
)
2149 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
2150 displaced
->step_ptid
= new_ptid
;
2157 /* Things to clean up if we QUIT out of resume (). */
2159 resume_cleanups (void *ignore
)
2161 if (!ptid_equal (inferior_ptid
, null_ptid
))
2162 delete_single_step_breakpoints (inferior_thread ());
2167 static const char schedlock_off
[] = "off";
2168 static const char schedlock_on
[] = "on";
2169 static const char schedlock_step
[] = "step";
2170 static const char schedlock_replay
[] = "replay";
2171 static const char *const scheduler_enums
[] = {
2178 static const char *scheduler_mode
= schedlock_replay
;
2180 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2181 struct cmd_list_element
*c
, const char *value
)
2183 fprintf_filtered (file
,
2184 _("Mode for locking scheduler "
2185 "during execution is \"%s\".\n"),
2190 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
2192 if (!target_can_lock_scheduler
)
2194 scheduler_mode
= schedlock_off
;
2195 error (_("Target '%s' cannot support this command."), target_shortname
);
2199 /* True if execution commands resume all threads of all processes by
2200 default; otherwise, resume only threads of the current inferior
2202 int sched_multi
= 0;
2204 /* Try to setup for software single stepping over the specified location.
2205 Return 1 if target_resume() should use hardware single step.
2207 GDBARCH the current gdbarch.
2208 PC the location to step over. */
2211 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2215 if (execution_direction
== EXEC_FORWARD
2216 && gdbarch_software_single_step_p (gdbarch
)
2217 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
2227 user_visible_resume_ptid (int step
)
2233 /* With non-stop mode on, threads are always handled
2235 resume_ptid
= inferior_ptid
;
2237 else if ((scheduler_mode
== schedlock_on
)
2238 || (scheduler_mode
== schedlock_step
&& step
))
2240 /* User-settable 'scheduler' mode requires solo thread
2242 resume_ptid
= inferior_ptid
;
2244 else if ((scheduler_mode
== schedlock_replay
)
2245 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2247 /* User-settable 'scheduler' mode requires solo thread resume in replay
2249 resume_ptid
= inferior_ptid
;
2251 else if (!sched_multi
&& target_supports_multi_process ())
2253 /* Resume all threads of the current process (and none of other
2255 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2259 /* Resume all threads of all processes. */
2260 resume_ptid
= RESUME_ALL
;
2266 /* Return a ptid representing the set of threads that we will resume,
2267 in the perspective of the target, assuming run control handling
2268 does not require leaving some threads stopped (e.g., stepping past
2269 breakpoint). USER_STEP indicates whether we're about to start the
2270 target for a stepping command. */
2273 internal_resume_ptid (int user_step
)
2275 /* In non-stop, we always control threads individually. Note that
2276 the target may always work in non-stop mode even with "set
2277 non-stop off", in which case user_visible_resume_ptid could
2278 return a wildcard ptid. */
2279 if (target_is_non_stop_p ())
2280 return inferior_ptid
;
2282 return user_visible_resume_ptid (user_step
);
2285 /* Wrapper for target_resume, that handles infrun-specific
2289 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2291 struct thread_info
*tp
= inferior_thread ();
2293 /* Install inferior's terminal modes. */
2294 target_terminal_inferior ();
2296 /* Avoid confusing the next resume, if the next stop/resume
2297 happens to apply to another thread. */
2298 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2300 /* Advise target which signals may be handled silently.
2302 If we have removed breakpoints because we are stepping over one
2303 in-line (in any thread), we need to receive all signals to avoid
2304 accidentally skipping a breakpoint during execution of a signal
2307 Likewise if we're displaced stepping, otherwise a trap for a
2308 breakpoint in a signal handler might be confused with the
2309 displaced step finishing. We don't make the displaced_step_fixup
2310 step distinguish the cases instead, because:
2312 - a backtrace while stopped in the signal handler would show the
2313 scratch pad as frame older than the signal handler, instead of
2314 the real mainline code.
2316 - when the thread is later resumed, the signal handler would
2317 return to the scratch pad area, which would no longer be
2319 if (step_over_info_valid_p ()
2320 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2321 target_pass_signals (0, NULL
);
2323 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2325 target_resume (resume_ptid
, step
, sig
);
2328 /* Resume the inferior, but allow a QUIT. This is useful if the user
2329 wants to interrupt some lengthy single-stepping operation
2330 (for child processes, the SIGINT goes to the inferior, and so
2331 we get a SIGINT random_signal, but for remote debugging and perhaps
2332 other targets, that's not true).
2334 SIG is the signal to give the inferior (zero for none). */
2336 resume (enum gdb_signal sig
)
2338 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2339 struct regcache
*regcache
= get_current_regcache ();
2340 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2341 struct thread_info
*tp
= inferior_thread ();
2342 CORE_ADDR pc
= regcache_read_pc (regcache
);
2343 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2345 /* This represents the user's step vs continue request. When
2346 deciding whether "set scheduler-locking step" applies, it's the
2347 user's intention that counts. */
2348 const int user_step
= tp
->control
.stepping_command
;
2349 /* This represents what we'll actually request the target to do.
2350 This can decay from a step to a continue, if e.g., we need to
2351 implement single-stepping with breakpoints (software
2355 gdb_assert (!thread_is_in_step_over_chain (tp
));
2359 if (tp
->suspend
.waitstatus_pending_p
)
2365 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2366 fprintf_unfiltered (gdb_stdlog
,
2367 "infrun: resume: thread %s has pending wait status %s "
2368 "(currently_stepping=%d).\n",
2369 target_pid_to_str (tp
->ptid
), statstr
,
2370 currently_stepping (tp
));
2376 /* FIXME: What should we do if we are supposed to resume this
2377 thread with a signal? Maybe we should maintain a queue of
2378 pending signals to deliver. */
2379 if (sig
!= GDB_SIGNAL_0
)
2381 warning (_("Couldn't deliver signal %s to %s."),
2382 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2385 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2386 discard_cleanups (old_cleanups
);
2388 if (target_can_async_p ())
2393 tp
->stepped_breakpoint
= 0;
2395 /* Depends on stepped_breakpoint. */
2396 step
= currently_stepping (tp
);
2398 if (current_inferior ()->waiting_for_vfork_done
)
2400 /* Don't try to single-step a vfork parent that is waiting for
2401 the child to get out of the shared memory region (by exec'ing
2402 or exiting). This is particularly important on software
2403 single-step archs, as the child process would trip on the
2404 software single step breakpoint inserted for the parent
2405 process. Since the parent will not actually execute any
2406 instruction until the child is out of the shared region (such
2407 are vfork's semantics), it is safe to simply continue it.
2408 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2409 the parent, and tell it to `keep_going', which automatically
2410 re-sets it stepping. */
2412 fprintf_unfiltered (gdb_stdlog
,
2413 "infrun: resume : clear step\n");
2418 fprintf_unfiltered (gdb_stdlog
,
2419 "infrun: resume (step=%d, signal=%s), "
2420 "trap_expected=%d, current thread [%s] at %s\n",
2421 step
, gdb_signal_to_symbol_string (sig
),
2422 tp
->control
.trap_expected
,
2423 target_pid_to_str (inferior_ptid
),
2424 paddress (gdbarch
, pc
));
2426 /* Normally, by the time we reach `resume', the breakpoints are either
2427 removed or inserted, as appropriate. The exception is if we're sitting
2428 at a permanent breakpoint; we need to step over it, but permanent
2429 breakpoints can't be removed. So we have to test for it here. */
2430 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2432 if (sig
!= GDB_SIGNAL_0
)
2434 /* We have a signal to pass to the inferior. The resume
2435 may, or may not take us to the signal handler. If this
2436 is a step, we'll need to stop in the signal handler, if
2437 there's one, (if the target supports stepping into
2438 handlers), or in the next mainline instruction, if
2439 there's no handler. If this is a continue, we need to be
2440 sure to run the handler with all breakpoints inserted.
2441 In all cases, set a breakpoint at the current address
2442 (where the handler returns to), and once that breakpoint
2443 is hit, resume skipping the permanent breakpoint. If
2444 that breakpoint isn't hit, then we've stepped into the
2445 signal handler (or hit some other event). We'll delete
2446 the step-resume breakpoint then. */
2449 fprintf_unfiltered (gdb_stdlog
,
2450 "infrun: resume: skipping permanent breakpoint, "
2451 "deliver signal first\n");
2453 clear_step_over_info ();
2454 tp
->control
.trap_expected
= 0;
2456 if (tp
->control
.step_resume_breakpoint
== NULL
)
2458 /* Set a "high-priority" step-resume, as we don't want
2459 user breakpoints at PC to trigger (again) when this
2461 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2462 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2464 tp
->step_after_step_resume_breakpoint
= step
;
2467 insert_breakpoints ();
2471 /* There's no signal to pass, we can go ahead and skip the
2472 permanent breakpoint manually. */
2474 fprintf_unfiltered (gdb_stdlog
,
2475 "infrun: resume: skipping permanent breakpoint\n");
2476 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2477 /* Update pc to reflect the new address from which we will
2478 execute instructions. */
2479 pc
= regcache_read_pc (regcache
);
2483 /* We've already advanced the PC, so the stepping part
2484 is done. Now we need to arrange for a trap to be
2485 reported to handle_inferior_event. Set a breakpoint
2486 at the current PC, and run to it. Don't update
2487 prev_pc, because if we end in
2488 switch_back_to_stepped_thread, we want the "expected
2489 thread advanced also" branch to be taken. IOW, we
2490 don't want this thread to step further from PC
2492 gdb_assert (!step_over_info_valid_p ());
2493 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2494 insert_breakpoints ();
2496 resume_ptid
= internal_resume_ptid (user_step
);
2497 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2498 discard_cleanups (old_cleanups
);
2505 /* If we have a breakpoint to step over, make sure to do a single
2506 step only. Same if we have software watchpoints. */
2507 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2508 tp
->control
.may_range_step
= 0;
2510 /* If enabled, step over breakpoints by executing a copy of the
2511 instruction at a different address.
2513 We can't use displaced stepping when we have a signal to deliver;
2514 the comments for displaced_step_prepare explain why. The
2515 comments in the handle_inferior event for dealing with 'random
2516 signals' explain what we do instead.
2518 We can't use displaced stepping when we are waiting for vfork_done
2519 event, displaced stepping breaks the vfork child similarly as single
2520 step software breakpoint. */
2521 if (tp
->control
.trap_expected
2522 && use_displaced_stepping (tp
)
2523 && !step_over_info_valid_p ()
2524 && sig
== GDB_SIGNAL_0
2525 && !current_inferior ()->waiting_for_vfork_done
)
2527 int prepared
= displaced_step_prepare (inferior_ptid
);
2532 fprintf_unfiltered (gdb_stdlog
,
2533 "Got placed in step-over queue\n");
2535 tp
->control
.trap_expected
= 0;
2536 discard_cleanups (old_cleanups
);
2539 else if (prepared
< 0)
2541 /* Fallback to stepping over the breakpoint in-line. */
2543 if (target_is_non_stop_p ())
2544 stop_all_threads ();
2546 set_step_over_info (get_regcache_aspace (regcache
),
2547 regcache_read_pc (regcache
), 0);
2549 step
= maybe_software_singlestep (gdbarch
, pc
);
2551 insert_breakpoints ();
2553 else if (prepared
> 0)
2555 struct displaced_step_inferior_state
*displaced
;
2557 /* Update pc to reflect the new address from which we will
2558 execute instructions due to displaced stepping. */
2559 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2561 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2562 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2563 displaced
->step_closure
);
2567 /* Do we need to do it the hard way, w/temp breakpoints? */
2569 step
= maybe_software_singlestep (gdbarch
, pc
);
2571 /* Currently, our software single-step implementation leads to different
2572 results than hardware single-stepping in one situation: when stepping
2573 into delivering a signal which has an associated signal handler,
2574 hardware single-step will stop at the first instruction of the handler,
2575 while software single-step will simply skip execution of the handler.
2577 For now, this difference in behavior is accepted since there is no
2578 easy way to actually implement single-stepping into a signal handler
2579 without kernel support.
2581 However, there is one scenario where this difference leads to follow-on
2582 problems: if we're stepping off a breakpoint by removing all breakpoints
2583 and then single-stepping. In this case, the software single-step
2584 behavior means that even if there is a *breakpoint* in the signal
2585 handler, GDB still would not stop.
2587 Fortunately, we can at least fix this particular issue. We detect
2588 here the case where we are about to deliver a signal while software
2589 single-stepping with breakpoints removed. In this situation, we
2590 revert the decisions to remove all breakpoints and insert single-
2591 step breakpoints, and instead we install a step-resume breakpoint
2592 at the current address, deliver the signal without stepping, and
2593 once we arrive back at the step-resume breakpoint, actually step
2594 over the breakpoint we originally wanted to step over. */
2595 if (thread_has_single_step_breakpoints_set (tp
)
2596 && sig
!= GDB_SIGNAL_0
2597 && step_over_info_valid_p ())
2599 /* If we have nested signals or a pending signal is delivered
2600 immediately after a handler returns, might might already have
2601 a step-resume breakpoint set on the earlier handler. We cannot
2602 set another step-resume breakpoint; just continue on until the
2603 original breakpoint is hit. */
2604 if (tp
->control
.step_resume_breakpoint
== NULL
)
2606 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2607 tp
->step_after_step_resume_breakpoint
= 1;
2610 delete_single_step_breakpoints (tp
);
2612 clear_step_over_info ();
2613 tp
->control
.trap_expected
= 0;
2615 insert_breakpoints ();
2618 /* If STEP is set, it's a request to use hardware stepping
2619 facilities. But in that case, we should never
2620 use singlestep breakpoint. */
2621 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2623 /* Decide the set of threads to ask the target to resume. */
2624 if ((step
|| thread_has_single_step_breakpoints_set (tp
))
2625 && tp
->control
.trap_expected
)
2627 /* We're allowing a thread to run past a breakpoint it has
2628 hit, by single-stepping the thread with the breakpoint
2629 removed. In which case, we need to single-step only this
2630 thread, and keep others stopped, as they can miss this
2631 breakpoint if allowed to run. */
2632 resume_ptid
= inferior_ptid
;
2635 resume_ptid
= internal_resume_ptid (user_step
);
2637 if (execution_direction
!= EXEC_REVERSE
2638 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2640 /* There are two cases where we currently need to step a
2641 breakpoint instruction when we have a signal to deliver:
2643 - See handle_signal_stop where we handle random signals that
2644 could take out us out of the stepping range. Normally, in
2645 that case we end up continuing (instead of stepping) over the
2646 signal handler with a breakpoint at PC, but there are cases
2647 where we should _always_ single-step, even if we have a
2648 step-resume breakpoint, like when a software watchpoint is
2649 set. Assuming single-stepping and delivering a signal at the
2650 same time would takes us to the signal handler, then we could
2651 have removed the breakpoint at PC to step over it. However,
2652 some hardware step targets (like e.g., Mac OS) can't step
2653 into signal handlers, and for those, we need to leave the
2654 breakpoint at PC inserted, as otherwise if the handler
2655 recurses and executes PC again, it'll miss the breakpoint.
2656 So we leave the breakpoint inserted anyway, but we need to
2657 record that we tried to step a breakpoint instruction, so
2658 that adjust_pc_after_break doesn't end up confused.
2660 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2661 in one thread after another thread that was stepping had been
2662 momentarily paused for a step-over. When we re-resume the
2663 stepping thread, it may be resumed from that address with a
2664 breakpoint that hasn't trapped yet. Seen with
2665 gdb.threads/non-stop-fair-events.exp, on targets that don't
2666 do displaced stepping. */
2669 fprintf_unfiltered (gdb_stdlog
,
2670 "infrun: resume: [%s] stepped breakpoint\n",
2671 target_pid_to_str (tp
->ptid
));
2673 tp
->stepped_breakpoint
= 1;
2675 /* Most targets can step a breakpoint instruction, thus
2676 executing it normally. But if this one cannot, just
2677 continue and we will hit it anyway. */
2678 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2683 && tp
->control
.trap_expected
2684 && use_displaced_stepping (tp
)
2685 && !step_over_info_valid_p ())
2687 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2688 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2689 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2692 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2693 paddress (resume_gdbarch
, actual_pc
));
2694 read_memory (actual_pc
, buf
, sizeof (buf
));
2695 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2698 if (tp
->control
.may_range_step
)
2700 /* If we're resuming a thread with the PC out of the step
2701 range, then we're doing some nested/finer run control
2702 operation, like stepping the thread out of the dynamic
2703 linker or the displaced stepping scratch pad. We
2704 shouldn't have allowed a range step then. */
2705 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2708 do_target_resume (resume_ptid
, step
, sig
);
2710 discard_cleanups (old_cleanups
);
2717 /* Counter that tracks number of user visible stops. This can be used
2718 to tell whether a command has proceeded the inferior past the
2719 current location. This allows e.g., inferior function calls in
2720 breakpoint commands to not interrupt the command list. When the
2721 call finishes successfully, the inferior is standing at the same
2722 breakpoint as if nothing happened (and so we don't call
2724 static ULONGEST current_stop_id
;
2731 return current_stop_id
;
2734 /* Called when we report a user visible stop. */
2742 /* Clear out all variables saying what to do when inferior is continued.
2743 First do this, then set the ones you want, then call `proceed'. */
2746 clear_proceed_status_thread (struct thread_info
*tp
)
2749 fprintf_unfiltered (gdb_stdlog
,
2750 "infrun: clear_proceed_status_thread (%s)\n",
2751 target_pid_to_str (tp
->ptid
));
2753 /* If we're starting a new sequence, then the previous finished
2754 single-step is no longer relevant. */
2755 if (tp
->suspend
.waitstatus_pending_p
)
2757 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2760 fprintf_unfiltered (gdb_stdlog
,
2761 "infrun: clear_proceed_status: pending "
2762 "event of %s was a finished step. "
2764 target_pid_to_str (tp
->ptid
));
2766 tp
->suspend
.waitstatus_pending_p
= 0;
2767 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2769 else if (debug_infrun
)
2773 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2774 fprintf_unfiltered (gdb_stdlog
,
2775 "infrun: clear_proceed_status_thread: thread %s "
2776 "has pending wait status %s "
2777 "(currently_stepping=%d).\n",
2778 target_pid_to_str (tp
->ptid
), statstr
,
2779 currently_stepping (tp
));
2784 /* If this signal should not be seen by program, give it zero.
2785 Used for debugging signals. */
2786 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2787 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2789 thread_fsm_delete (tp
->thread_fsm
);
2790 tp
->thread_fsm
= NULL
;
2792 tp
->control
.trap_expected
= 0;
2793 tp
->control
.step_range_start
= 0;
2794 tp
->control
.step_range_end
= 0;
2795 tp
->control
.may_range_step
= 0;
2796 tp
->control
.step_frame_id
= null_frame_id
;
2797 tp
->control
.step_stack_frame_id
= null_frame_id
;
2798 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2799 tp
->control
.step_start_function
= NULL
;
2800 tp
->stop_requested
= 0;
2802 tp
->control
.stop_step
= 0;
2804 tp
->control
.proceed_to_finish
= 0;
2806 tp
->control
.command_interp
= NULL
;
2807 tp
->control
.stepping_command
= 0;
2809 /* Discard any remaining commands or status from previous stop. */
2810 bpstat_clear (&tp
->control
.stop_bpstat
);
2814 clear_proceed_status (int step
)
2816 /* With scheduler-locking replay, stop replaying other threads if we're
2817 not replaying the user-visible resume ptid.
2819 This is a convenience feature to not require the user to explicitly
2820 stop replaying the other threads. We're assuming that the user's
2821 intent is to resume tracing the recorded process. */
2822 if (!non_stop
&& scheduler_mode
== schedlock_replay
2823 && target_record_is_replaying (minus_one_ptid
)
2824 && !target_record_will_replay (user_visible_resume_ptid (step
),
2825 execution_direction
))
2826 target_record_stop_replaying ();
2830 struct thread_info
*tp
;
2833 resume_ptid
= user_visible_resume_ptid (step
);
2835 /* In all-stop mode, delete the per-thread status of all threads
2836 we're about to resume, implicitly and explicitly. */
2837 ALL_NON_EXITED_THREADS (tp
)
2839 if (!ptid_match (tp
->ptid
, resume_ptid
))
2841 clear_proceed_status_thread (tp
);
2845 if (!ptid_equal (inferior_ptid
, null_ptid
))
2847 struct inferior
*inferior
;
2851 /* If in non-stop mode, only delete the per-thread status of
2852 the current thread. */
2853 clear_proceed_status_thread (inferior_thread ());
2856 inferior
= current_inferior ();
2857 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2860 stop_after_trap
= 0;
2862 observer_notify_about_to_proceed ();
2865 /* Returns true if TP is still stopped at a breakpoint that needs
2866 stepping-over in order to make progress. If the breakpoint is gone
2867 meanwhile, we can skip the whole step-over dance. */
2870 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2872 if (tp
->stepping_over_breakpoint
)
2874 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2876 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2877 regcache_read_pc (regcache
))
2878 == ordinary_breakpoint_here
)
2881 tp
->stepping_over_breakpoint
= 0;
2887 /* Check whether thread TP still needs to start a step-over in order
2888 to make progress when resumed. Returns an bitwise or of enum
2889 step_over_what bits, indicating what needs to be stepped over. */
2892 thread_still_needs_step_over (struct thread_info
*tp
)
2894 struct inferior
*inf
= find_inferior_ptid (tp
->ptid
);
2897 if (thread_still_needs_step_over_bp (tp
))
2898 what
|= STEP_OVER_BREAKPOINT
;
2900 if (tp
->stepping_over_watchpoint
2901 && !target_have_steppable_watchpoint
)
2902 what
|= STEP_OVER_WATCHPOINT
;
2907 /* Returns true if scheduler locking applies. STEP indicates whether
2908 we're about to do a step/next-like command to a thread. */
2911 schedlock_applies (struct thread_info
*tp
)
2913 return (scheduler_mode
== schedlock_on
2914 || (scheduler_mode
== schedlock_step
2915 && tp
->control
.stepping_command
)
2916 || (scheduler_mode
== schedlock_replay
2917 && target_record_will_replay (minus_one_ptid
,
2918 execution_direction
)));
2921 /* Basic routine for continuing the program in various fashions.
2923 ADDR is the address to resume at, or -1 for resume where stopped.
2924 SIGGNAL is the signal to give it, or 0 for none,
2925 or -1 for act according to how it stopped.
2926 STEP is nonzero if should trap after one instruction.
2927 -1 means return after that and print nothing.
2928 You should probably set various step_... variables
2929 before calling here, if you are stepping.
2931 You should call clear_proceed_status before calling proceed. */
2934 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2936 struct regcache
*regcache
;
2937 struct gdbarch
*gdbarch
;
2938 struct thread_info
*tp
;
2940 struct address_space
*aspace
;
2942 struct execution_control_state ecss
;
2943 struct execution_control_state
*ecs
= &ecss
;
2944 struct cleanup
*old_chain
;
2947 /* If we're stopped at a fork/vfork, follow the branch set by the
2948 "set follow-fork-mode" command; otherwise, we'll just proceed
2949 resuming the current thread. */
2950 if (!follow_fork ())
2952 /* The target for some reason decided not to resume. */
2954 if (target_can_async_p ())
2955 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2959 /* We'll update this if & when we switch to a new thread. */
2960 previous_inferior_ptid
= inferior_ptid
;
2962 regcache
= get_current_regcache ();
2963 gdbarch
= get_regcache_arch (regcache
);
2964 aspace
= get_regcache_aspace (regcache
);
2965 pc
= regcache_read_pc (regcache
);
2966 tp
= inferior_thread ();
2968 /* Fill in with reasonable starting values. */
2969 init_thread_stepping_state (tp
);
2971 gdb_assert (!thread_is_in_step_over_chain (tp
));
2973 if (addr
== (CORE_ADDR
) -1)
2976 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
2977 && execution_direction
!= EXEC_REVERSE
)
2978 /* There is a breakpoint at the address we will resume at,
2979 step one instruction before inserting breakpoints so that
2980 we do not stop right away (and report a second hit at this
2983 Note, we don't do this in reverse, because we won't
2984 actually be executing the breakpoint insn anyway.
2985 We'll be (un-)executing the previous instruction. */
2986 tp
->stepping_over_breakpoint
= 1;
2987 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2988 && gdbarch_single_step_through_delay (gdbarch
,
2989 get_current_frame ()))
2990 /* We stepped onto an instruction that needs to be stepped
2991 again before re-inserting the breakpoint, do so. */
2992 tp
->stepping_over_breakpoint
= 1;
2996 regcache_write_pc (regcache
, addr
);
2999 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3000 tp
->suspend
.stop_signal
= siggnal
;
3002 /* Record the interpreter that issued the execution command that
3003 caused this thread to resume. If the top level interpreter is
3004 MI/async, and the execution command was a CLI command
3005 (next/step/etc.), we'll want to print stop event output to the MI
3006 console channel (the stepped-to line, etc.), as if the user
3007 entered the execution command on a real GDB console. */
3008 tp
->control
.command_interp
= command_interp ();
3010 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3012 /* If an exception is thrown from this point on, make sure to
3013 propagate GDB's knowledge of the executing state to the
3014 frontend/user running state. */
3015 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3017 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3018 threads (e.g., we might need to set threads stepping over
3019 breakpoints first), from the user/frontend's point of view, all
3020 threads in RESUME_PTID are now running. Unless we're calling an
3021 inferior function, as in that case we pretend the inferior
3022 doesn't run at all. */
3023 if (!tp
->control
.in_infcall
)
3024 set_running (resume_ptid
, 1);
3027 fprintf_unfiltered (gdb_stdlog
,
3028 "infrun: proceed (addr=%s, signal=%s)\n",
3029 paddress (gdbarch
, addr
),
3030 gdb_signal_to_symbol_string (siggnal
));
3032 annotate_starting ();
3034 /* Make sure that output from GDB appears before output from the
3036 gdb_flush (gdb_stdout
);
3038 /* In a multi-threaded task we may select another thread and
3039 then continue or step.
3041 But if a thread that we're resuming had stopped at a breakpoint,
3042 it will immediately cause another breakpoint stop without any
3043 execution (i.e. it will report a breakpoint hit incorrectly). So
3044 we must step over it first.
3046 Look for threads other than the current (TP) that reported a
3047 breakpoint hit and haven't been resumed yet since. */
3049 /* If scheduler locking applies, we can avoid iterating over all
3051 if (!non_stop
&& !schedlock_applies (tp
))
3053 struct thread_info
*current
= tp
;
3055 ALL_NON_EXITED_THREADS (tp
)
3057 /* Ignore the current thread here. It's handled
3062 /* Ignore threads of processes we're not resuming. */
3063 if (!ptid_match (tp
->ptid
, resume_ptid
))
3066 if (!thread_still_needs_step_over (tp
))
3069 gdb_assert (!thread_is_in_step_over_chain (tp
));
3072 fprintf_unfiltered (gdb_stdlog
,
3073 "infrun: need to step-over [%s] first\n",
3074 target_pid_to_str (tp
->ptid
));
3076 thread_step_over_chain_enqueue (tp
);
3082 /* Enqueue the current thread last, so that we move all other
3083 threads over their breakpoints first. */
3084 if (tp
->stepping_over_breakpoint
)
3085 thread_step_over_chain_enqueue (tp
);
3087 /* If the thread isn't started, we'll still need to set its prev_pc,
3088 so that switch_back_to_stepped_thread knows the thread hasn't
3089 advanced. Must do this before resuming any thread, as in
3090 all-stop/remote, once we resume we can't send any other packet
3091 until the target stops again. */
3092 tp
->prev_pc
= regcache_read_pc (regcache
);
3094 started
= start_step_over ();
3096 if (step_over_info_valid_p ())
3098 /* Either this thread started a new in-line step over, or some
3099 other thread was already doing one. In either case, don't
3100 resume anything else until the step-over is finished. */
3102 else if (started
&& !target_is_non_stop_p ())
3104 /* A new displaced stepping sequence was started. In all-stop,
3105 we can't talk to the target anymore until it next stops. */
3107 else if (!non_stop
&& target_is_non_stop_p ())
3109 /* In all-stop, but the target is always in non-stop mode.
3110 Start all other threads that are implicitly resumed too. */
3111 ALL_NON_EXITED_THREADS (tp
)
3113 /* Ignore threads of processes we're not resuming. */
3114 if (!ptid_match (tp
->ptid
, resume_ptid
))
3120 fprintf_unfiltered (gdb_stdlog
,
3121 "infrun: proceed: [%s] resumed\n",
3122 target_pid_to_str (tp
->ptid
));
3123 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3127 if (thread_is_in_step_over_chain (tp
))
3130 fprintf_unfiltered (gdb_stdlog
,
3131 "infrun: proceed: [%s] needs step-over\n",
3132 target_pid_to_str (tp
->ptid
));
3137 fprintf_unfiltered (gdb_stdlog
,
3138 "infrun: proceed: resuming %s\n",
3139 target_pid_to_str (tp
->ptid
));
3141 reset_ecs (ecs
, tp
);
3142 switch_to_thread (tp
->ptid
);
3143 keep_going_pass_signal (ecs
);
3144 if (!ecs
->wait_some_more
)
3145 error (_("Command aborted."));
3148 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3150 /* The thread wasn't started, and isn't queued, run it now. */
3151 reset_ecs (ecs
, tp
);
3152 switch_to_thread (tp
->ptid
);
3153 keep_going_pass_signal (ecs
);
3154 if (!ecs
->wait_some_more
)
3155 error (_("Command aborted."));
3158 discard_cleanups (old_chain
);
3160 /* Tell the event loop to wait for it to stop. If the target
3161 supports asynchronous execution, it'll do this from within
3163 if (!target_can_async_p ())
3164 mark_async_event_handler (infrun_async_inferior_event_token
);
3168 /* Start remote-debugging of a machine over a serial link. */
3171 start_remote (int from_tty
)
3173 struct inferior
*inferior
;
3175 inferior
= current_inferior ();
3176 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3178 /* Always go on waiting for the target, regardless of the mode. */
3179 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3180 indicate to wait_for_inferior that a target should timeout if
3181 nothing is returned (instead of just blocking). Because of this,
3182 targets expecting an immediate response need to, internally, set
3183 things up so that the target_wait() is forced to eventually
3185 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3186 differentiate to its caller what the state of the target is after
3187 the initial open has been performed. Here we're assuming that
3188 the target has stopped. It should be possible to eventually have
3189 target_open() return to the caller an indication that the target
3190 is currently running and GDB state should be set to the same as
3191 for an async run. */
3192 wait_for_inferior ();
3194 /* Now that the inferior has stopped, do any bookkeeping like
3195 loading shared libraries. We want to do this before normal_stop,
3196 so that the displayed frame is up to date. */
3197 post_create_inferior (¤t_target
, from_tty
);
3202 /* Initialize static vars when a new inferior begins. */
3205 init_wait_for_inferior (void)
3207 /* These are meaningless until the first time through wait_for_inferior. */
3209 breakpoint_init_inferior (inf_starting
);
3211 clear_proceed_status (0);
3213 target_last_wait_ptid
= minus_one_ptid
;
3215 previous_inferior_ptid
= inferior_ptid
;
3217 /* Discard any skipped inlined frames. */
3218 clear_inline_frame_state (minus_one_ptid
);
3223 static void handle_inferior_event (struct execution_control_state
*ecs
);
3225 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3226 struct execution_control_state
*ecs
);
3227 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3228 struct execution_control_state
*ecs
);
3229 static void handle_signal_stop (struct execution_control_state
*ecs
);
3230 static void check_exception_resume (struct execution_control_state
*,
3231 struct frame_info
*);
3233 static void end_stepping_range (struct execution_control_state
*ecs
);
3234 static void stop_waiting (struct execution_control_state
*ecs
);
3235 static void keep_going (struct execution_control_state
*ecs
);
3236 static void process_event_stop_test (struct execution_control_state
*ecs
);
3237 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3239 /* Callback for iterate over threads. If the thread is stopped, but
3240 the user/frontend doesn't know about that yet, go through
3241 normal_stop, as if the thread had just stopped now. ARG points at
3242 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
3243 ptid_is_pid(PTID) is true, applies to all threads of the process
3244 pointed at by PTID. Otherwise, apply only to the thread pointed by
3248 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
3250 ptid_t ptid
= * (ptid_t
*) arg
;
3252 if ((ptid_equal (info
->ptid
, ptid
)
3253 || ptid_equal (minus_one_ptid
, ptid
)
3254 || (ptid_is_pid (ptid
)
3255 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
3256 && is_running (info
->ptid
)
3257 && !is_executing (info
->ptid
))
3259 struct cleanup
*old_chain
;
3260 struct execution_control_state ecss
;
3261 struct execution_control_state
*ecs
= &ecss
;
3263 memset (ecs
, 0, sizeof (*ecs
));
3265 old_chain
= make_cleanup_restore_current_thread ();
3267 overlay_cache_invalid
= 1;
3268 /* Flush target cache before starting to handle each event.
3269 Target was running and cache could be stale. This is just a
3270 heuristic. Running threads may modify target memory, but we
3271 don't get any event. */
3272 target_dcache_invalidate ();
3274 /* Go through handle_inferior_event/normal_stop, so we always
3275 have consistent output as if the stop event had been
3277 ecs
->ptid
= info
->ptid
;
3278 ecs
->event_thread
= info
;
3279 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
3280 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
3282 handle_inferior_event (ecs
);
3284 if (!ecs
->wait_some_more
)
3286 /* Cancel any running execution command. */
3287 thread_cancel_execution_command (info
);
3292 do_cleanups (old_chain
);
3298 /* This function is attached as a "thread_stop_requested" observer.
3299 Cleanup local state that assumed the PTID was to be resumed, and
3300 report the stop to the frontend. */
3303 infrun_thread_stop_requested (ptid_t ptid
)
3305 struct thread_info
*tp
;
3307 /* PTID was requested to stop. Remove matching threads from the
3308 step-over queue, so we don't try to resume them
3310 ALL_NON_EXITED_THREADS (tp
)
3311 if (ptid_match (tp
->ptid
, ptid
))
3313 if (thread_is_in_step_over_chain (tp
))
3314 thread_step_over_chain_remove (tp
);
3317 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
3321 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3323 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3324 nullify_last_target_wait_ptid ();
3327 /* Delete the step resume, single-step and longjmp/exception resume
3328 breakpoints of TP. */
3331 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3333 delete_step_resume_breakpoint (tp
);
3334 delete_exception_resume_breakpoint (tp
);
3335 delete_single_step_breakpoints (tp
);
3338 /* If the target still has execution, call FUNC for each thread that
3339 just stopped. In all-stop, that's all the non-exited threads; in
3340 non-stop, that's the current thread, only. */
3342 typedef void (*for_each_just_stopped_thread_callback_func
)
3343 (struct thread_info
*tp
);
3346 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3348 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3351 if (target_is_non_stop_p ())
3353 /* If in non-stop mode, only the current thread stopped. */
3354 func (inferior_thread ());
3358 struct thread_info
*tp
;
3360 /* In all-stop mode, all threads have stopped. */
3361 ALL_NON_EXITED_THREADS (tp
)
3368 /* Delete the step resume and longjmp/exception resume breakpoints of
3369 the threads that just stopped. */
3372 delete_just_stopped_threads_infrun_breakpoints (void)
3374 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3377 /* Delete the single-step breakpoints of the threads that just
3381 delete_just_stopped_threads_single_step_breakpoints (void)
3383 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3386 /* A cleanup wrapper. */
3389 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3391 delete_just_stopped_threads_infrun_breakpoints ();
3397 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3398 const struct target_waitstatus
*ws
)
3400 char *status_string
= target_waitstatus_to_string (ws
);
3401 struct ui_file
*tmp_stream
= mem_fileopen ();
3404 /* The text is split over several lines because it was getting too long.
3405 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3406 output as a unit; we want only one timestamp printed if debug_timestamp
3409 fprintf_unfiltered (tmp_stream
,
3410 "infrun: target_wait (%d.%ld.%ld",
3411 ptid_get_pid (waiton_ptid
),
3412 ptid_get_lwp (waiton_ptid
),
3413 ptid_get_tid (waiton_ptid
));
3414 if (ptid_get_pid (waiton_ptid
) != -1)
3415 fprintf_unfiltered (tmp_stream
,
3416 " [%s]", target_pid_to_str (waiton_ptid
));
3417 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3418 fprintf_unfiltered (tmp_stream
,
3419 "infrun: %d.%ld.%ld [%s],\n",
3420 ptid_get_pid (result_ptid
),
3421 ptid_get_lwp (result_ptid
),
3422 ptid_get_tid (result_ptid
),
3423 target_pid_to_str (result_ptid
));
3424 fprintf_unfiltered (tmp_stream
,
3428 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3430 /* This uses %s in part to handle %'s in the text, but also to avoid
3431 a gcc error: the format attribute requires a string literal. */
3432 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3434 xfree (status_string
);
3436 ui_file_delete (tmp_stream
);
3439 /* Select a thread at random, out of those which are resumed and have
3442 static struct thread_info
*
3443 random_pending_event_thread (ptid_t waiton_ptid
)
3445 struct thread_info
*event_tp
;
3447 int random_selector
;
3449 /* First see how many events we have. Count only resumed threads
3450 that have an event pending. */
3451 ALL_NON_EXITED_THREADS (event_tp
)
3452 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3453 && event_tp
->resumed
3454 && event_tp
->suspend
.waitstatus_pending_p
)
3457 if (num_events
== 0)
3460 /* Now randomly pick a thread out of those that have had events. */
3461 random_selector
= (int)
3462 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3464 if (debug_infrun
&& num_events
> 1)
3465 fprintf_unfiltered (gdb_stdlog
,
3466 "infrun: Found %d events, selecting #%d\n",
3467 num_events
, random_selector
);
3469 /* Select the Nth thread that has had an event. */
3470 ALL_NON_EXITED_THREADS (event_tp
)
3471 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3472 && event_tp
->resumed
3473 && event_tp
->suspend
.waitstatus_pending_p
)
3474 if (random_selector
-- == 0)
3480 /* Wrapper for target_wait that first checks whether threads have
3481 pending statuses to report before actually asking the target for
3485 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3488 struct thread_info
*tp
;
3490 /* First check if there is a resumed thread with a wait status
3492 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3494 tp
= random_pending_event_thread (ptid
);
3499 fprintf_unfiltered (gdb_stdlog
,
3500 "infrun: Waiting for specific thread %s.\n",
3501 target_pid_to_str (ptid
));
3503 /* We have a specific thread to check. */
3504 tp
= find_thread_ptid (ptid
);
3505 gdb_assert (tp
!= NULL
);
3506 if (!tp
->suspend
.waitstatus_pending_p
)
3511 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3512 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3514 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3515 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3519 pc
= regcache_read_pc (regcache
);
3521 if (pc
!= tp
->suspend
.stop_pc
)
3524 fprintf_unfiltered (gdb_stdlog
,
3525 "infrun: PC of %s changed. was=%s, now=%s\n",
3526 target_pid_to_str (tp
->ptid
),
3527 paddress (gdbarch
, tp
->prev_pc
),
3528 paddress (gdbarch
, pc
));
3531 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3534 fprintf_unfiltered (gdb_stdlog
,
3535 "infrun: previous breakpoint of %s, at %s gone\n",
3536 target_pid_to_str (tp
->ptid
),
3537 paddress (gdbarch
, pc
));
3545 fprintf_unfiltered (gdb_stdlog
,
3546 "infrun: pending event of %s cancelled.\n",
3547 target_pid_to_str (tp
->ptid
));
3549 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3550 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3560 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3561 fprintf_unfiltered (gdb_stdlog
,
3562 "infrun: Using pending wait status %s for %s.\n",
3564 target_pid_to_str (tp
->ptid
));
3568 /* Now that we've selected our final event LWP, un-adjust its PC
3569 if it was a software breakpoint (and the target doesn't
3570 always adjust the PC itself). */
3571 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3572 && !target_supports_stopped_by_sw_breakpoint ())
3574 struct regcache
*regcache
;
3575 struct gdbarch
*gdbarch
;
3578 regcache
= get_thread_regcache (tp
->ptid
);
3579 gdbarch
= get_regcache_arch (regcache
);
3581 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3586 pc
= regcache_read_pc (regcache
);
3587 regcache_write_pc (regcache
, pc
+ decr_pc
);
3591 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3592 *status
= tp
->suspend
.waitstatus
;
3593 tp
->suspend
.waitstatus_pending_p
= 0;
3595 /* Wake up the event loop again, until all pending events are
3597 if (target_is_async_p ())
3598 mark_async_event_handler (infrun_async_inferior_event_token
);
3602 /* But if we don't find one, we'll have to wait. */
3604 if (deprecated_target_wait_hook
)
3605 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3607 event_ptid
= target_wait (ptid
, status
, options
);
3612 /* Prepare and stabilize the inferior for detaching it. E.g.,
3613 detaching while a thread is displaced stepping is a recipe for
3614 crashing it, as nothing would readjust the PC out of the scratch
3618 prepare_for_detach (void)
3620 struct inferior
*inf
= current_inferior ();
3621 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3622 struct cleanup
*old_chain_1
;
3623 struct displaced_step_inferior_state
*displaced
;
3625 displaced
= get_displaced_stepping_state (inf
->pid
);
3627 /* Is any thread of this process displaced stepping? If not,
3628 there's nothing else to do. */
3629 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3633 fprintf_unfiltered (gdb_stdlog
,
3634 "displaced-stepping in-process while detaching");
3636 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3639 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3641 struct cleanup
*old_chain_2
;
3642 struct execution_control_state ecss
;
3643 struct execution_control_state
*ecs
;
3646 memset (ecs
, 0, sizeof (*ecs
));
3648 overlay_cache_invalid
= 1;
3649 /* Flush target cache before starting to handle each event.
3650 Target was running and cache could be stale. This is just a
3651 heuristic. Running threads may modify target memory, but we
3652 don't get any event. */
3653 target_dcache_invalidate ();
3655 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3658 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3660 /* If an error happens while handling the event, propagate GDB's
3661 knowledge of the executing state to the frontend/user running
3663 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3666 /* Now figure out what to do with the result of the result. */
3667 handle_inferior_event (ecs
);
3669 /* No error, don't finish the state yet. */
3670 discard_cleanups (old_chain_2
);
3672 /* Breakpoints and watchpoints are not installed on the target
3673 at this point, and signals are passed directly to the
3674 inferior, so this must mean the process is gone. */
3675 if (!ecs
->wait_some_more
)
3677 discard_cleanups (old_chain_1
);
3678 error (_("Program exited while detaching"));
3682 discard_cleanups (old_chain_1
);
3685 /* Wait for control to return from inferior to debugger.
3687 If inferior gets a signal, we may decide to start it up again
3688 instead of returning. That is why there is a loop in this function.
3689 When this function actually returns it means the inferior
3690 should be left stopped and GDB should read more commands. */
3693 wait_for_inferior (void)
3695 struct cleanup
*old_cleanups
;
3696 struct cleanup
*thread_state_chain
;
3700 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3703 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3706 /* If an error happens while handling the event, propagate GDB's
3707 knowledge of the executing state to the frontend/user running
3709 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3713 struct execution_control_state ecss
;
3714 struct execution_control_state
*ecs
= &ecss
;
3715 ptid_t waiton_ptid
= minus_one_ptid
;
3717 memset (ecs
, 0, sizeof (*ecs
));
3719 overlay_cache_invalid
= 1;
3721 /* Flush target cache before starting to handle each event.
3722 Target was running and cache could be stale. This is just a
3723 heuristic. Running threads may modify target memory, but we
3724 don't get any event. */
3725 target_dcache_invalidate ();
3727 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3730 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3732 /* Now figure out what to do with the result of the result. */
3733 handle_inferior_event (ecs
);
3735 if (!ecs
->wait_some_more
)
3739 /* No error, don't finish the state yet. */
3740 discard_cleanups (thread_state_chain
);
3742 do_cleanups (old_cleanups
);
3745 /* Cleanup that reinstalls the readline callback handler, if the
3746 target is running in the background. If while handling the target
3747 event something triggered a secondary prompt, like e.g., a
3748 pagination prompt, we'll have removed the callback handler (see
3749 gdb_readline_wrapper_line). Need to do this as we go back to the
3750 event loop, ready to process further input. Note this has no
3751 effect if the handler hasn't actually been removed, because calling
3752 rl_callback_handler_install resets the line buffer, thus losing
3756 reinstall_readline_callback_handler_cleanup (void *arg
)
3758 if (!interpreter_async
)
3760 /* We're not going back to the top level event loop yet. Don't
3761 install the readline callback, as it'd prep the terminal,
3762 readline-style (raw, noecho) (e.g., --batch). We'll install
3763 it the next time the prompt is displayed, when we're ready
3768 if (async_command_editing_p
&& !sync_execution
)
3769 gdb_rl_callback_handler_reinstall ();
3772 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3773 that's just the event thread. In all-stop, that's all threads. */
3776 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3778 struct thread_info
*thr
= ecs
->event_thread
;
3780 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3781 thread_fsm_clean_up (thr
->thread_fsm
);
3785 ALL_NON_EXITED_THREADS (thr
)
3787 if (thr
->thread_fsm
== NULL
)
3789 if (thr
== ecs
->event_thread
)
3792 switch_to_thread (thr
->ptid
);
3793 thread_fsm_clean_up (thr
->thread_fsm
);
3796 if (ecs
->event_thread
!= NULL
)
3797 switch_to_thread (ecs
->event_thread
->ptid
);
3801 /* Asynchronous version of wait_for_inferior. It is called by the
3802 event loop whenever a change of state is detected on the file
3803 descriptor corresponding to the target. It can be called more than
3804 once to complete a single execution command. In such cases we need
3805 to keep the state in a global variable ECSS. If it is the last time
3806 that this function is called for a single execution command, then
3807 report to the user that the inferior has stopped, and do the
3808 necessary cleanups. */
3811 fetch_inferior_event (void *client_data
)
3813 struct execution_control_state ecss
;
3814 struct execution_control_state
*ecs
= &ecss
;
3815 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3816 struct cleanup
*ts_old_chain
;
3817 int was_sync
= sync_execution
;
3819 ptid_t waiton_ptid
= minus_one_ptid
;
3821 memset (ecs
, 0, sizeof (*ecs
));
3823 /* End up with readline processing input, if necessary. */
3824 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3826 /* We're handling a live event, so make sure we're doing live
3827 debugging. If we're looking at traceframes while the target is
3828 running, we're going to need to get back to that mode after
3829 handling the event. */
3832 make_cleanup_restore_current_traceframe ();
3833 set_current_traceframe (-1);
3837 /* In non-stop mode, the user/frontend should not notice a thread
3838 switch due to internal events. Make sure we reverse to the
3839 user selected thread and frame after handling the event and
3840 running any breakpoint commands. */
3841 make_cleanup_restore_current_thread ();
3843 overlay_cache_invalid
= 1;
3844 /* Flush target cache before starting to handle each event. Target
3845 was running and cache could be stale. This is just a heuristic.
3846 Running threads may modify target memory, but we don't get any
3848 target_dcache_invalidate ();
3850 make_cleanup_restore_integer (&execution_direction
);
3851 execution_direction
= target_execution_direction ();
3853 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3854 target_can_async_p () ? TARGET_WNOHANG
: 0);
3857 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3859 /* If an error happens while handling the event, propagate GDB's
3860 knowledge of the executing state to the frontend/user running
3862 if (!target_is_non_stop_p ())
3863 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3865 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3867 /* Get executed before make_cleanup_restore_current_thread above to apply
3868 still for the thread which has thrown the exception. */
3869 make_bpstat_clear_actions_cleanup ();
3871 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3873 /* Now figure out what to do with the result of the result. */
3874 handle_inferior_event (ecs
);
3876 if (!ecs
->wait_some_more
)
3878 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3879 int should_stop
= 1;
3880 struct thread_info
*thr
= ecs
->event_thread
;
3881 int should_notify_stop
= 1;
3883 delete_just_stopped_threads_infrun_breakpoints ();
3887 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3889 if (thread_fsm
!= NULL
)
3890 should_stop
= thread_fsm_should_stop (thread_fsm
);
3899 clean_up_just_stopped_threads_fsms (ecs
);
3901 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3904 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
3907 if (should_notify_stop
)
3911 /* We may not find an inferior if this was a process exit. */
3912 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3913 proceeded
= normal_stop ();
3917 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3924 /* No error, don't finish the thread states yet. */
3925 discard_cleanups (ts_old_chain
);
3927 /* Revert thread and frame. */
3928 do_cleanups (old_chain
);
3930 /* If the inferior was in sync execution mode, and now isn't,
3931 restore the prompt (a synchronous execution command has finished,
3932 and we're ready for input). */
3933 if (interpreter_async
&& was_sync
&& !sync_execution
)
3934 observer_notify_sync_execution_done ();
3938 && exec_done_display_p
3939 && (ptid_equal (inferior_ptid
, null_ptid
)
3940 || !is_running (inferior_ptid
)))
3941 printf_unfiltered (_("completed.\n"));
3944 /* Record the frame and location we're currently stepping through. */
3946 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3948 struct thread_info
*tp
= inferior_thread ();
3950 tp
->control
.step_frame_id
= get_frame_id (frame
);
3951 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3953 tp
->current_symtab
= sal
.symtab
;
3954 tp
->current_line
= sal
.line
;
3957 /* Clear context switchable stepping state. */
3960 init_thread_stepping_state (struct thread_info
*tss
)
3962 tss
->stepped_breakpoint
= 0;
3963 tss
->stepping_over_breakpoint
= 0;
3964 tss
->stepping_over_watchpoint
= 0;
3965 tss
->step_after_step_resume_breakpoint
= 0;
3968 /* Set the cached copy of the last ptid/waitstatus. */
3971 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
3973 target_last_wait_ptid
= ptid
;
3974 target_last_waitstatus
= status
;
3977 /* Return the cached copy of the last pid/waitstatus returned by
3978 target_wait()/deprecated_target_wait_hook(). The data is actually
3979 cached by handle_inferior_event(), which gets called immediately
3980 after target_wait()/deprecated_target_wait_hook(). */
3983 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
3985 *ptidp
= target_last_wait_ptid
;
3986 *status
= target_last_waitstatus
;
3990 nullify_last_target_wait_ptid (void)
3992 target_last_wait_ptid
= minus_one_ptid
;
3995 /* Switch thread contexts. */
3998 context_switch (ptid_t ptid
)
4000 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4002 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4003 target_pid_to_str (inferior_ptid
));
4004 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4005 target_pid_to_str (ptid
));
4008 switch_to_thread (ptid
);
4011 /* If the target can't tell whether we've hit breakpoints
4012 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4013 check whether that could have been caused by a breakpoint. If so,
4014 adjust the PC, per gdbarch_decr_pc_after_break. */
4017 adjust_pc_after_break (struct thread_info
*thread
,
4018 struct target_waitstatus
*ws
)
4020 struct regcache
*regcache
;
4021 struct gdbarch
*gdbarch
;
4022 struct address_space
*aspace
;
4023 CORE_ADDR breakpoint_pc
, decr_pc
;
4025 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4026 we aren't, just return.
4028 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4029 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4030 implemented by software breakpoints should be handled through the normal
4033 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4034 different signals (SIGILL or SIGEMT for instance), but it is less
4035 clear where the PC is pointing afterwards. It may not match
4036 gdbarch_decr_pc_after_break. I don't know any specific target that
4037 generates these signals at breakpoints (the code has been in GDB since at
4038 least 1992) so I can not guess how to handle them here.
4040 In earlier versions of GDB, a target with
4041 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4042 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4043 target with both of these set in GDB history, and it seems unlikely to be
4044 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4046 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4049 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4052 /* In reverse execution, when a breakpoint is hit, the instruction
4053 under it has already been de-executed. The reported PC always
4054 points at the breakpoint address, so adjusting it further would
4055 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4058 B1 0x08000000 : INSN1
4059 B2 0x08000001 : INSN2
4061 PC -> 0x08000003 : INSN4
4063 Say you're stopped at 0x08000003 as above. Reverse continuing
4064 from that point should hit B2 as below. Reading the PC when the
4065 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4066 been de-executed already.
4068 B1 0x08000000 : INSN1
4069 B2 PC -> 0x08000001 : INSN2
4073 We can't apply the same logic as for forward execution, because
4074 we would wrongly adjust the PC to 0x08000000, since there's a
4075 breakpoint at PC - 1. We'd then report a hit on B1, although
4076 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4078 if (execution_direction
== EXEC_REVERSE
)
4081 /* If the target can tell whether the thread hit a SW breakpoint,
4082 trust it. Targets that can tell also adjust the PC
4084 if (target_supports_stopped_by_sw_breakpoint ())
4087 /* Note that relying on whether a breakpoint is planted in memory to
4088 determine this can fail. E.g,. the breakpoint could have been
4089 removed since. Or the thread could have been told to step an
4090 instruction the size of a breakpoint instruction, and only
4091 _after_ was a breakpoint inserted at its address. */
4093 /* If this target does not decrement the PC after breakpoints, then
4094 we have nothing to do. */
4095 regcache
= get_thread_regcache (thread
->ptid
);
4096 gdbarch
= get_regcache_arch (regcache
);
4098 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4102 aspace
= get_regcache_aspace (regcache
);
4104 /* Find the location where (if we've hit a breakpoint) the
4105 breakpoint would be. */
4106 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4108 /* If the target can't tell whether a software breakpoint triggered,
4109 fallback to figuring it out based on breakpoints we think were
4110 inserted in the target, and on whether the thread was stepped or
4113 /* Check whether there actually is a software breakpoint inserted at
4116 If in non-stop mode, a race condition is possible where we've
4117 removed a breakpoint, but stop events for that breakpoint were
4118 already queued and arrive later. To suppress those spurious
4119 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4120 and retire them after a number of stop events are reported. Note
4121 this is an heuristic and can thus get confused. The real fix is
4122 to get the "stopped by SW BP and needs adjustment" info out of
4123 the target/kernel (and thus never reach here; see above). */
4124 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4125 || (target_is_non_stop_p ()
4126 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4128 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4130 if (record_full_is_used ())
4131 record_full_gdb_operation_disable_set ();
4133 /* When using hardware single-step, a SIGTRAP is reported for both
4134 a completed single-step and a software breakpoint. Need to
4135 differentiate between the two, as the latter needs adjusting
4136 but the former does not.
4138 The SIGTRAP can be due to a completed hardware single-step only if
4139 - we didn't insert software single-step breakpoints
4140 - this thread is currently being stepped
4142 If any of these events did not occur, we must have stopped due
4143 to hitting a software breakpoint, and have to back up to the
4146 As a special case, we could have hardware single-stepped a
4147 software breakpoint. In this case (prev_pc == breakpoint_pc),
4148 we also need to back up to the breakpoint address. */
4150 if (thread_has_single_step_breakpoints_set (thread
)
4151 || !currently_stepping (thread
)
4152 || (thread
->stepped_breakpoint
4153 && thread
->prev_pc
== breakpoint_pc
))
4154 regcache_write_pc (regcache
, breakpoint_pc
);
4156 do_cleanups (old_cleanups
);
4161 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4163 for (frame
= get_prev_frame (frame
);
4165 frame
= get_prev_frame (frame
))
4167 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4169 if (get_frame_type (frame
) != INLINE_FRAME
)
4176 /* Auxiliary function that handles syscall entry/return events.
4177 It returns 1 if the inferior should keep going (and GDB
4178 should ignore the event), or 0 if the event deserves to be
4182 handle_syscall_event (struct execution_control_state
*ecs
)
4184 struct regcache
*regcache
;
4187 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4188 context_switch (ecs
->ptid
);
4190 regcache
= get_thread_regcache (ecs
->ptid
);
4191 syscall_number
= ecs
->ws
.value
.syscall_number
;
4192 stop_pc
= regcache_read_pc (regcache
);
4194 if (catch_syscall_enabled () > 0
4195 && catching_syscall_number (syscall_number
) > 0)
4198 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4201 ecs
->event_thread
->control
.stop_bpstat
4202 = bpstat_stop_status (get_regcache_aspace (regcache
),
4203 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4205 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4207 /* Catchpoint hit. */
4212 /* If no catchpoint triggered for this, then keep going. */
4217 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4220 fill_in_stop_func (struct gdbarch
*gdbarch
,
4221 struct execution_control_state
*ecs
)
4223 if (!ecs
->stop_func_filled_in
)
4225 /* Don't care about return value; stop_func_start and stop_func_name
4226 will both be 0 if it doesn't work. */
4227 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4228 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4229 ecs
->stop_func_start
4230 += gdbarch_deprecated_function_start_offset (gdbarch
);
4232 if (gdbarch_skip_entrypoint_p (gdbarch
))
4233 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4234 ecs
->stop_func_start
);
4236 ecs
->stop_func_filled_in
= 1;
4241 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4243 static enum stop_kind
4244 get_inferior_stop_soon (ptid_t ptid
)
4246 struct inferior
*inf
= find_inferior_ptid (ptid
);
4248 gdb_assert (inf
!= NULL
);
4249 return inf
->control
.stop_soon
;
4252 /* Wait for one event. Store the resulting waitstatus in WS, and
4253 return the event ptid. */
4256 wait_one (struct target_waitstatus
*ws
)
4259 ptid_t wait_ptid
= minus_one_ptid
;
4261 overlay_cache_invalid
= 1;
4263 /* Flush target cache before starting to handle each event.
4264 Target was running and cache could be stale. This is just a
4265 heuristic. Running threads may modify target memory, but we
4266 don't get any event. */
4267 target_dcache_invalidate ();
4269 if (deprecated_target_wait_hook
)
4270 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4272 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4275 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4280 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4281 instead of the current thread. */
4282 #define THREAD_STOPPED_BY(REASON) \
4284 thread_stopped_by_ ## REASON (ptid_t ptid) \
4286 struct cleanup *old_chain; \
4289 old_chain = save_inferior_ptid (); \
4290 inferior_ptid = ptid; \
4292 res = target_stopped_by_ ## REASON (); \
4294 do_cleanups (old_chain); \
4299 /* Generate thread_stopped_by_watchpoint. */
4300 THREAD_STOPPED_BY (watchpoint
)
4301 /* Generate thread_stopped_by_sw_breakpoint. */
4302 THREAD_STOPPED_BY (sw_breakpoint
)
4303 /* Generate thread_stopped_by_hw_breakpoint. */
4304 THREAD_STOPPED_BY (hw_breakpoint
)
4306 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4309 switch_to_thread_cleanup (void *ptid_p
)
4311 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4313 switch_to_thread (ptid
);
4316 /* Save the thread's event and stop reason to process it later. */
4319 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4321 struct regcache
*regcache
;
4322 struct address_space
*aspace
;
4328 statstr
= target_waitstatus_to_string (ws
);
4329 fprintf_unfiltered (gdb_stdlog
,
4330 "infrun: saving status %s for %d.%ld.%ld\n",
4332 ptid_get_pid (tp
->ptid
),
4333 ptid_get_lwp (tp
->ptid
),
4334 ptid_get_tid (tp
->ptid
));
4338 /* Record for later. */
4339 tp
->suspend
.waitstatus
= *ws
;
4340 tp
->suspend
.waitstatus_pending_p
= 1;
4342 regcache
= get_thread_regcache (tp
->ptid
);
4343 aspace
= get_regcache_aspace (regcache
);
4345 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4346 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4348 CORE_ADDR pc
= regcache_read_pc (regcache
);
4350 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4352 if (thread_stopped_by_watchpoint (tp
->ptid
))
4354 tp
->suspend
.stop_reason
4355 = TARGET_STOPPED_BY_WATCHPOINT
;
4357 else if (target_supports_stopped_by_sw_breakpoint ()
4358 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4360 tp
->suspend
.stop_reason
4361 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4363 else if (target_supports_stopped_by_hw_breakpoint ()
4364 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4366 tp
->suspend
.stop_reason
4367 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4369 else if (!target_supports_stopped_by_hw_breakpoint ()
4370 && hardware_breakpoint_inserted_here_p (aspace
,
4373 tp
->suspend
.stop_reason
4374 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4376 else if (!target_supports_stopped_by_sw_breakpoint ()
4377 && software_breakpoint_inserted_here_p (aspace
,
4380 tp
->suspend
.stop_reason
4381 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4383 else if (!thread_has_single_step_breakpoints_set (tp
)
4384 && currently_stepping (tp
))
4386 tp
->suspend
.stop_reason
4387 = TARGET_STOPPED_BY_SINGLE_STEP
;
4392 /* Stop all threads. */
4395 stop_all_threads (void)
4397 /* We may need multiple passes to discover all threads. */
4401 struct cleanup
*old_chain
;
4403 gdb_assert (target_is_non_stop_p ());
4406 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4408 entry_ptid
= inferior_ptid
;
4409 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4411 /* Request threads to stop, and then wait for the stops. Because
4412 threads we already know about can spawn more threads while we're
4413 trying to stop them, and we only learn about new threads when we
4414 update the thread list, do this in a loop, and keep iterating
4415 until two passes find no threads that need to be stopped. */
4416 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4419 fprintf_unfiltered (gdb_stdlog
,
4420 "infrun: stop_all_threads, pass=%d, "
4421 "iterations=%d\n", pass
, iterations
);
4425 struct target_waitstatus ws
;
4427 struct thread_info
*t
;
4429 update_thread_list ();
4431 /* Go through all threads looking for threads that we need
4432 to tell the target to stop. */
4433 ALL_NON_EXITED_THREADS (t
)
4437 /* If already stopping, don't request a stop again.
4438 We just haven't seen the notification yet. */
4439 if (!t
->stop_requested
)
4442 fprintf_unfiltered (gdb_stdlog
,
4443 "infrun: %s executing, "
4445 target_pid_to_str (t
->ptid
));
4446 target_stop (t
->ptid
);
4447 t
->stop_requested
= 1;
4452 fprintf_unfiltered (gdb_stdlog
,
4453 "infrun: %s executing, "
4454 "already stopping\n",
4455 target_pid_to_str (t
->ptid
));
4458 if (t
->stop_requested
)
4464 fprintf_unfiltered (gdb_stdlog
,
4465 "infrun: %s not executing\n",
4466 target_pid_to_str (t
->ptid
));
4468 /* The thread may be not executing, but still be
4469 resumed with a pending status to process. */
4477 /* If we find new threads on the second iteration, restart
4478 over. We want to see two iterations in a row with all
4483 event_ptid
= wait_one (&ws
);
4484 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4486 /* All resumed threads exited. */
4488 else if (ws
.kind
== TARGET_WAITKIND_EXITED
4489 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4493 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4495 fprintf_unfiltered (gdb_stdlog
,
4496 "infrun: %s exited while "
4497 "stopping threads\n",
4498 target_pid_to_str (ptid
));
4503 t
= find_thread_ptid (event_ptid
);
4505 t
= add_thread (event_ptid
);
4507 t
->stop_requested
= 0;
4510 t
->control
.may_range_step
= 0;
4512 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4513 && ws
.value
.sig
== GDB_SIGNAL_0
)
4515 /* We caught the event that we intended to catch, so
4516 there's no event pending. */
4517 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4518 t
->suspend
.waitstatus_pending_p
= 0;
4520 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4522 /* Add it back to the step-over queue. */
4525 fprintf_unfiltered (gdb_stdlog
,
4526 "infrun: displaced-step of %s "
4527 "canceled: adding back to the "
4528 "step-over queue\n",
4529 target_pid_to_str (t
->ptid
));
4531 t
->control
.trap_expected
= 0;
4532 thread_step_over_chain_enqueue (t
);
4537 enum gdb_signal sig
;
4538 struct regcache
*regcache
;
4539 struct address_space
*aspace
;
4545 statstr
= target_waitstatus_to_string (&ws
);
4546 fprintf_unfiltered (gdb_stdlog
,
4547 "infrun: target_wait %s, saving "
4548 "status for %d.%ld.%ld\n",
4550 ptid_get_pid (t
->ptid
),
4551 ptid_get_lwp (t
->ptid
),
4552 ptid_get_tid (t
->ptid
));
4556 /* Record for later. */
4557 save_waitstatus (t
, &ws
);
4559 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4560 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4562 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4564 /* Add it back to the step-over queue. */
4565 t
->control
.trap_expected
= 0;
4566 thread_step_over_chain_enqueue (t
);
4569 regcache
= get_thread_regcache (t
->ptid
);
4570 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4574 fprintf_unfiltered (gdb_stdlog
,
4575 "infrun: saved stop_pc=%s for %s "
4576 "(currently_stepping=%d)\n",
4577 paddress (target_gdbarch (),
4578 t
->suspend
.stop_pc
),
4579 target_pid_to_str (t
->ptid
),
4580 currently_stepping (t
));
4587 do_cleanups (old_chain
);
4590 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4593 /* Given an execution control state that has been freshly filled in by
4594 an event from the inferior, figure out what it means and take
4597 The alternatives are:
4599 1) stop_waiting and return; to really stop and return to the
4602 2) keep_going and return; to wait for the next event (set
4603 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4607 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4609 enum stop_kind stop_soon
;
4611 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4613 /* We had an event in the inferior, but we are not interested in
4614 handling it at this level. The lower layers have already
4615 done what needs to be done, if anything.
4617 One of the possible circumstances for this is when the
4618 inferior produces output for the console. The inferior has
4619 not stopped, and we are ignoring the event. Another possible
4620 circumstance is any event which the lower level knows will be
4621 reported multiple times without an intervening resume. */
4623 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4624 prepare_to_wait (ecs
);
4628 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4629 && target_can_async_p () && !sync_execution
)
4631 /* There were no unwaited-for children left in the target, but,
4632 we're not synchronously waiting for events either. Just
4633 ignore. Otherwise, if we were running a synchronous
4634 execution command, we need to cancel it and give the user
4635 back the terminal. */
4637 fprintf_unfiltered (gdb_stdlog
,
4638 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
4639 prepare_to_wait (ecs
);
4643 /* Cache the last pid/waitstatus. */
4644 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4646 /* Always clear state belonging to the previous time we stopped. */
4647 stop_stack_dummy
= STOP_NONE
;
4649 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4651 /* No unwaited-for children left. IOW, all resumed children
4654 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4656 stop_print_frame
= 0;
4661 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4662 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4664 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4665 /* If it's a new thread, add it to the thread database. */
4666 if (ecs
->event_thread
== NULL
)
4667 ecs
->event_thread
= add_thread (ecs
->ptid
);
4669 /* Disable range stepping. If the next step request could use a
4670 range, this will be end up re-enabled then. */
4671 ecs
->event_thread
->control
.may_range_step
= 0;
4674 /* Dependent on valid ECS->EVENT_THREAD. */
4675 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4677 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4678 reinit_frame_cache ();
4680 breakpoint_retire_moribund ();
4682 /* First, distinguish signals caused by the debugger from signals
4683 that have to do with the program's own actions. Note that
4684 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4685 on the operating system version. Here we detect when a SIGILL or
4686 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4687 something similar for SIGSEGV, since a SIGSEGV will be generated
4688 when we're trying to execute a breakpoint instruction on a
4689 non-executable stack. This happens for call dummy breakpoints
4690 for architectures like SPARC that place call dummies on the
4692 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4693 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4694 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4695 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4697 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4699 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4700 regcache_read_pc (regcache
)))
4703 fprintf_unfiltered (gdb_stdlog
,
4704 "infrun: Treating signal as SIGTRAP\n");
4705 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4709 /* Mark the non-executing threads accordingly. In all-stop, all
4710 threads of all processes are stopped when we get any event
4711 reported. In non-stop mode, only the event thread stops. */
4715 if (!target_is_non_stop_p ())
4716 mark_ptid
= minus_one_ptid
;
4717 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4718 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4720 /* If we're handling a process exit in non-stop mode, even
4721 though threads haven't been deleted yet, one would think
4722 that there is nothing to do, as threads of the dead process
4723 will be soon deleted, and threads of any other process were
4724 left running. However, on some targets, threads survive a
4725 process exit event. E.g., for the "checkpoint" command,
4726 when the current checkpoint/fork exits, linux-fork.c
4727 automatically switches to another fork from within
4728 target_mourn_inferior, by associating the same
4729 inferior/thread to another fork. We haven't mourned yet at
4730 this point, but we must mark any threads left in the
4731 process as not-executing so that finish_thread_state marks
4732 them stopped (in the user's perspective) if/when we present
4733 the stop to the user. */
4734 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4737 mark_ptid
= ecs
->ptid
;
4739 set_executing (mark_ptid
, 0);
4741 /* Likewise the resumed flag. */
4742 set_resumed (mark_ptid
, 0);
4745 switch (ecs
->ws
.kind
)
4747 case TARGET_WAITKIND_LOADED
:
4749 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4750 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4751 context_switch (ecs
->ptid
);
4752 /* Ignore gracefully during startup of the inferior, as it might
4753 be the shell which has just loaded some objects, otherwise
4754 add the symbols for the newly loaded objects. Also ignore at
4755 the beginning of an attach or remote session; we will query
4756 the full list of libraries once the connection is
4759 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4760 if (stop_soon
== NO_STOP_QUIETLY
)
4762 struct regcache
*regcache
;
4764 regcache
= get_thread_regcache (ecs
->ptid
);
4766 handle_solib_event ();
4768 ecs
->event_thread
->control
.stop_bpstat
4769 = bpstat_stop_status (get_regcache_aspace (regcache
),
4770 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4772 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4774 /* A catchpoint triggered. */
4775 process_event_stop_test (ecs
);
4779 /* If requested, stop when the dynamic linker notifies
4780 gdb of events. This allows the user to get control
4781 and place breakpoints in initializer routines for
4782 dynamically loaded objects (among other things). */
4783 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4784 if (stop_on_solib_events
)
4786 /* Make sure we print "Stopped due to solib-event" in
4788 stop_print_frame
= 1;
4795 /* If we are skipping through a shell, or through shared library
4796 loading that we aren't interested in, resume the program. If
4797 we're running the program normally, also resume. */
4798 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
4800 /* Loading of shared libraries might have changed breakpoint
4801 addresses. Make sure new breakpoints are inserted. */
4802 if (stop_soon
== NO_STOP_QUIETLY
)
4803 insert_breakpoints ();
4804 resume (GDB_SIGNAL_0
);
4805 prepare_to_wait (ecs
);
4809 /* But stop if we're attaching or setting up a remote
4811 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4812 || stop_soon
== STOP_QUIETLY_REMOTE
)
4815 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4820 internal_error (__FILE__
, __LINE__
,
4821 _("unhandled stop_soon: %d"), (int) stop_soon
);
4823 case TARGET_WAITKIND_SPURIOUS
:
4825 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
4826 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4827 context_switch (ecs
->ptid
);
4828 resume (GDB_SIGNAL_0
);
4829 prepare_to_wait (ecs
);
4832 case TARGET_WAITKIND_EXITED
:
4833 case TARGET_WAITKIND_SIGNALLED
:
4836 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4837 fprintf_unfiltered (gdb_stdlog
,
4838 "infrun: TARGET_WAITKIND_EXITED\n");
4840 fprintf_unfiltered (gdb_stdlog
,
4841 "infrun: TARGET_WAITKIND_SIGNALLED\n");
4844 inferior_ptid
= ecs
->ptid
;
4845 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
4846 set_current_program_space (current_inferior ()->pspace
);
4847 handle_vfork_child_exec_or_exit (0);
4848 target_terminal_ours (); /* Must do this before mourn anyway. */
4850 /* Clearing any previous state of convenience variables. */
4851 clear_exit_convenience_vars ();
4853 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4855 /* Record the exit code in the convenience variable $_exitcode, so
4856 that the user can inspect this again later. */
4857 set_internalvar_integer (lookup_internalvar ("_exitcode"),
4858 (LONGEST
) ecs
->ws
.value
.integer
);
4860 /* Also record this in the inferior itself. */
4861 current_inferior ()->has_exit_code
= 1;
4862 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
4864 /* Support the --return-child-result option. */
4865 return_child_result_value
= ecs
->ws
.value
.integer
;
4867 observer_notify_exited (ecs
->ws
.value
.integer
);
4871 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4872 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4874 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
4876 /* Set the value of the internal variable $_exitsignal,
4877 which holds the signal uncaught by the inferior. */
4878 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
4879 gdbarch_gdb_signal_to_target (gdbarch
,
4880 ecs
->ws
.value
.sig
));
4884 /* We don't have access to the target's method used for
4885 converting between signal numbers (GDB's internal
4886 representation <-> target's representation).
4887 Therefore, we cannot do a good job at displaying this
4888 information to the user. It's better to just warn
4889 her about it (if infrun debugging is enabled), and
4892 fprintf_filtered (gdb_stdlog
, _("\
4893 Cannot fill $_exitsignal with the correct signal number.\n"));
4896 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
4899 gdb_flush (gdb_stdout
);
4900 target_mourn_inferior ();
4901 stop_print_frame
= 0;
4905 /* The following are the only cases in which we keep going;
4906 the above cases end in a continue or goto. */
4907 case TARGET_WAITKIND_FORKED
:
4908 case TARGET_WAITKIND_VFORKED
:
4911 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4912 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
4914 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
4917 /* Check whether the inferior is displaced stepping. */
4919 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4920 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4921 struct displaced_step_inferior_state
*displaced
4922 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
4924 /* If checking displaced stepping is supported, and thread
4925 ecs->ptid is displaced stepping. */
4926 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
4928 struct inferior
*parent_inf
4929 = find_inferior_ptid (ecs
->ptid
);
4930 struct regcache
*child_regcache
;
4931 CORE_ADDR parent_pc
;
4933 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
4934 indicating that the displaced stepping of syscall instruction
4935 has been done. Perform cleanup for parent process here. Note
4936 that this operation also cleans up the child process for vfork,
4937 because their pages are shared. */
4938 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
4939 /* Start a new step-over in another thread if there's one
4943 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4945 /* Restore scratch pad for child process. */
4946 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
4949 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
4950 the child's PC is also within the scratchpad. Set the child's PC
4951 to the parent's PC value, which has already been fixed up.
4952 FIXME: we use the parent's aspace here, although we're touching
4953 the child, because the child hasn't been added to the inferior
4954 list yet at this point. */
4957 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
4959 parent_inf
->aspace
);
4960 /* Read PC value of parent process. */
4961 parent_pc
= regcache_read_pc (regcache
);
4963 if (debug_displaced
)
4964 fprintf_unfiltered (gdb_stdlog
,
4965 "displaced: write child pc from %s to %s\n",
4967 regcache_read_pc (child_regcache
)),
4968 paddress (gdbarch
, parent_pc
));
4970 regcache_write_pc (child_regcache
, parent_pc
);
4974 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4975 context_switch (ecs
->ptid
);
4977 /* Immediately detach breakpoints from the child before there's
4978 any chance of letting the user delete breakpoints from the
4979 breakpoint lists. If we don't do this early, it's easy to
4980 leave left over traps in the child, vis: "break foo; catch
4981 fork; c; <fork>; del; c; <child calls foo>". We only follow
4982 the fork on the last `continue', and by that time the
4983 breakpoint at "foo" is long gone from the breakpoint table.
4984 If we vforked, then we don't need to unpatch here, since both
4985 parent and child are sharing the same memory pages; we'll
4986 need to unpatch at follow/detach time instead to be certain
4987 that new breakpoints added between catchpoint hit time and
4988 vfork follow are detached. */
4989 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
4991 /* This won't actually modify the breakpoint list, but will
4992 physically remove the breakpoints from the child. */
4993 detach_breakpoints (ecs
->ws
.value
.related_pid
);
4996 delete_just_stopped_threads_single_step_breakpoints ();
4998 /* In case the event is caught by a catchpoint, remember that
4999 the event is to be followed at the next resume of the thread,
5000 and not immediately. */
5001 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5003 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5005 ecs
->event_thread
->control
.stop_bpstat
5006 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5007 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5009 /* If no catchpoint triggered for this, then keep going. Note
5010 that we're interested in knowing the bpstat actually causes a
5011 stop, not just if it may explain the signal. Software
5012 watchpoints, for example, always appear in the bpstat. */
5013 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5019 = (follow_fork_mode_string
== follow_fork_mode_child
);
5021 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5023 should_resume
= follow_fork ();
5026 child
= ecs
->ws
.value
.related_pid
;
5028 /* In non-stop mode, also resume the other branch. */
5029 if (!detach_fork
&& (non_stop
5030 || (sched_multi
&& target_is_non_stop_p ())))
5033 switch_to_thread (parent
);
5035 switch_to_thread (child
);
5037 ecs
->event_thread
= inferior_thread ();
5038 ecs
->ptid
= inferior_ptid
;
5043 switch_to_thread (child
);
5045 switch_to_thread (parent
);
5047 ecs
->event_thread
= inferior_thread ();
5048 ecs
->ptid
= inferior_ptid
;
5056 process_event_stop_test (ecs
);
5059 case TARGET_WAITKIND_VFORK_DONE
:
5060 /* Done with the shared memory region. Re-insert breakpoints in
5061 the parent, and keep going. */
5064 fprintf_unfiltered (gdb_stdlog
,
5065 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5067 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5068 context_switch (ecs
->ptid
);
5070 current_inferior ()->waiting_for_vfork_done
= 0;
5071 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5072 /* This also takes care of reinserting breakpoints in the
5073 previously locked inferior. */
5077 case TARGET_WAITKIND_EXECD
:
5079 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5081 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5082 context_switch (ecs
->ptid
);
5084 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5086 /* Do whatever is necessary to the parent branch of the vfork. */
5087 handle_vfork_child_exec_or_exit (1);
5089 /* This causes the eventpoints and symbol table to be reset.
5090 Must do this now, before trying to determine whether to
5092 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5094 /* In follow_exec we may have deleted the original thread and
5095 created a new one. Make sure that the event thread is the
5096 execd thread for that case (this is a nop otherwise). */
5097 ecs
->event_thread
= inferior_thread ();
5099 ecs
->event_thread
->control
.stop_bpstat
5100 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5101 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5103 /* Note that this may be referenced from inside
5104 bpstat_stop_status above, through inferior_has_execd. */
5105 xfree (ecs
->ws
.value
.execd_pathname
);
5106 ecs
->ws
.value
.execd_pathname
= NULL
;
5108 /* If no catchpoint triggered for this, then keep going. */
5109 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5111 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5115 process_event_stop_test (ecs
);
5118 /* Be careful not to try to gather much state about a thread
5119 that's in a syscall. It's frequently a losing proposition. */
5120 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5122 fprintf_unfiltered (gdb_stdlog
,
5123 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5124 /* Getting the current syscall number. */
5125 if (handle_syscall_event (ecs
) == 0)
5126 process_event_stop_test (ecs
);
5129 /* Before examining the threads further, step this thread to
5130 get it entirely out of the syscall. (We get notice of the
5131 event when the thread is just on the verge of exiting a
5132 syscall. Stepping one instruction seems to get it back
5134 case TARGET_WAITKIND_SYSCALL_RETURN
:
5136 fprintf_unfiltered (gdb_stdlog
,
5137 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5138 if (handle_syscall_event (ecs
) == 0)
5139 process_event_stop_test (ecs
);
5142 case TARGET_WAITKIND_STOPPED
:
5144 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5145 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5146 handle_signal_stop (ecs
);
5149 case TARGET_WAITKIND_NO_HISTORY
:
5151 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5152 /* Reverse execution: target ran out of history info. */
5154 /* Switch to the stopped thread. */
5155 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5156 context_switch (ecs
->ptid
);
5158 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5160 delete_just_stopped_threads_single_step_breakpoints ();
5161 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5162 observer_notify_no_history ();
5168 /* A wrapper around handle_inferior_event_1, which also makes sure
5169 that all temporary struct value objects that were created during
5170 the handling of the event get deleted at the end. */
5173 handle_inferior_event (struct execution_control_state
*ecs
)
5175 struct value
*mark
= value_mark ();
5177 handle_inferior_event_1 (ecs
);
5178 /* Purge all temporary values created during the event handling,
5179 as it could be a long time before we return to the command level
5180 where such values would otherwise be purged. */
5181 value_free_to_mark (mark
);
5184 /* Restart threads back to what they were trying to do back when we
5185 paused them for an in-line step-over. The EVENT_THREAD thread is
5189 restart_threads (struct thread_info
*event_thread
)
5191 struct thread_info
*tp
;
5192 struct thread_info
*step_over
= NULL
;
5194 /* In case the instruction just stepped spawned a new thread. */
5195 update_thread_list ();
5197 ALL_NON_EXITED_THREADS (tp
)
5199 if (tp
== event_thread
)
5202 fprintf_unfiltered (gdb_stdlog
,
5203 "infrun: restart threads: "
5204 "[%s] is event thread\n",
5205 target_pid_to_str (tp
->ptid
));
5209 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5212 fprintf_unfiltered (gdb_stdlog
,
5213 "infrun: restart threads: "
5214 "[%s] not meant to be running\n",
5215 target_pid_to_str (tp
->ptid
));
5222 fprintf_unfiltered (gdb_stdlog
,
5223 "infrun: restart threads: [%s] resumed\n",
5224 target_pid_to_str (tp
->ptid
));
5225 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5229 if (thread_is_in_step_over_chain (tp
))
5232 fprintf_unfiltered (gdb_stdlog
,
5233 "infrun: restart threads: "
5234 "[%s] needs step-over\n",
5235 target_pid_to_str (tp
->ptid
));
5236 gdb_assert (!tp
->resumed
);
5241 if (tp
->suspend
.waitstatus_pending_p
)
5244 fprintf_unfiltered (gdb_stdlog
,
5245 "infrun: restart threads: "
5246 "[%s] has pending status\n",
5247 target_pid_to_str (tp
->ptid
));
5252 /* If some thread needs to start a step-over at this point, it
5253 should still be in the step-over queue, and thus skipped
5255 if (thread_still_needs_step_over (tp
))
5257 internal_error (__FILE__
, __LINE__
,
5258 "thread [%s] needs a step-over, but not in "
5259 "step-over queue\n",
5260 target_pid_to_str (tp
->ptid
));
5263 if (currently_stepping (tp
))
5266 fprintf_unfiltered (gdb_stdlog
,
5267 "infrun: restart threads: [%s] was stepping\n",
5268 target_pid_to_str (tp
->ptid
));
5269 keep_going_stepped_thread (tp
);
5273 struct execution_control_state ecss
;
5274 struct execution_control_state
*ecs
= &ecss
;
5277 fprintf_unfiltered (gdb_stdlog
,
5278 "infrun: restart threads: [%s] continuing\n",
5279 target_pid_to_str (tp
->ptid
));
5280 reset_ecs (ecs
, tp
);
5281 switch_to_thread (tp
->ptid
);
5282 keep_going_pass_signal (ecs
);
5287 /* Callback for iterate_over_threads. Find a resumed thread that has
5288 a pending waitstatus. */
5291 resumed_thread_with_pending_status (struct thread_info
*tp
,
5295 && tp
->suspend
.waitstatus_pending_p
);
5298 /* Called when we get an event that may finish an in-line or
5299 out-of-line (displaced stepping) step-over started previously.
5300 Return true if the event is processed and we should go back to the
5301 event loop; false if the caller should continue processing the
5305 finish_step_over (struct execution_control_state
*ecs
)
5307 int had_step_over_info
;
5309 displaced_step_fixup (ecs
->ptid
,
5310 ecs
->event_thread
->suspend
.stop_signal
);
5312 had_step_over_info
= step_over_info_valid_p ();
5314 if (had_step_over_info
)
5316 /* If we're stepping over a breakpoint with all threads locked,
5317 then only the thread that was stepped should be reporting
5319 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5321 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5322 clear_step_over_info ();
5325 if (!target_is_non_stop_p ())
5328 /* Start a new step-over in another thread if there's one that
5332 /* If we were stepping over a breakpoint before, and haven't started
5333 a new in-line step-over sequence, then restart all other threads
5334 (except the event thread). We can't do this in all-stop, as then
5335 e.g., we wouldn't be able to issue any other remote packet until
5336 these other threads stop. */
5337 if (had_step_over_info
&& !step_over_info_valid_p ())
5339 struct thread_info
*pending
;
5341 /* If we only have threads with pending statuses, the restart
5342 below won't restart any thread and so nothing re-inserts the
5343 breakpoint we just stepped over. But we need it inserted
5344 when we later process the pending events, otherwise if
5345 another thread has a pending event for this breakpoint too,
5346 we'd discard its event (because the breakpoint that
5347 originally caused the event was no longer inserted). */
5348 context_switch (ecs
->ptid
);
5349 insert_breakpoints ();
5351 restart_threads (ecs
->event_thread
);
5353 /* If we have events pending, go through handle_inferior_event
5354 again, picking up a pending event at random. This avoids
5355 thread starvation. */
5357 /* But not if we just stepped over a watchpoint in order to let
5358 the instruction execute so we can evaluate its expression.
5359 The set of watchpoints that triggered is recorded in the
5360 breakpoint objects themselves (see bp->watchpoint_triggered).
5361 If we processed another event first, that other event could
5362 clobber this info. */
5363 if (ecs
->event_thread
->stepping_over_watchpoint
)
5366 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5368 if (pending
!= NULL
)
5370 struct thread_info
*tp
= ecs
->event_thread
;
5371 struct regcache
*regcache
;
5375 fprintf_unfiltered (gdb_stdlog
,
5376 "infrun: found resumed threads with "
5377 "pending events, saving status\n");
5380 gdb_assert (pending
!= tp
);
5382 /* Record the event thread's event for later. */
5383 save_waitstatus (tp
, &ecs
->ws
);
5384 /* This was cleared early, by handle_inferior_event. Set it
5385 so this pending event is considered by
5389 gdb_assert (!tp
->executing
);
5391 regcache
= get_thread_regcache (tp
->ptid
);
5392 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5396 fprintf_unfiltered (gdb_stdlog
,
5397 "infrun: saved stop_pc=%s for %s "
5398 "(currently_stepping=%d)\n",
5399 paddress (target_gdbarch (),
5400 tp
->suspend
.stop_pc
),
5401 target_pid_to_str (tp
->ptid
),
5402 currently_stepping (tp
));
5405 /* This in-line step-over finished; clear this so we won't
5406 start a new one. This is what handle_signal_stop would
5407 do, if we returned false. */
5408 tp
->stepping_over_breakpoint
= 0;
5410 /* Wake up the event loop again. */
5411 mark_async_event_handler (infrun_async_inferior_event_token
);
5413 prepare_to_wait (ecs
);
5421 /* Come here when the program has stopped with a signal. */
5424 handle_signal_stop (struct execution_control_state
*ecs
)
5426 struct frame_info
*frame
;
5427 struct gdbarch
*gdbarch
;
5428 int stopped_by_watchpoint
;
5429 enum stop_kind stop_soon
;
5432 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5434 /* Do we need to clean up the state of a thread that has
5435 completed a displaced single-step? (Doing so usually affects
5436 the PC, so do it here, before we set stop_pc.) */
5437 if (finish_step_over (ecs
))
5440 /* If we either finished a single-step or hit a breakpoint, but
5441 the user wanted this thread to be stopped, pretend we got a
5442 SIG0 (generic unsignaled stop). */
5443 if (ecs
->event_thread
->stop_requested
5444 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5445 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5447 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5451 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5452 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5453 struct cleanup
*old_chain
= save_inferior_ptid ();
5455 inferior_ptid
= ecs
->ptid
;
5457 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5458 paddress (gdbarch
, stop_pc
));
5459 if (target_stopped_by_watchpoint ())
5463 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5465 if (target_stopped_data_address (¤t_target
, &addr
))
5466 fprintf_unfiltered (gdb_stdlog
,
5467 "infrun: stopped data address = %s\n",
5468 paddress (gdbarch
, addr
));
5470 fprintf_unfiltered (gdb_stdlog
,
5471 "infrun: (no data address available)\n");
5474 do_cleanups (old_chain
);
5477 /* This is originated from start_remote(), start_inferior() and
5478 shared libraries hook functions. */
5479 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5480 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5482 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5483 context_switch (ecs
->ptid
);
5485 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5486 stop_print_frame
= 1;
5491 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5494 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5495 context_switch (ecs
->ptid
);
5497 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5498 stop_print_frame
= 0;
5503 /* This originates from attach_command(). We need to overwrite
5504 the stop_signal here, because some kernels don't ignore a
5505 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5506 See more comments in inferior.h. On the other hand, if we
5507 get a non-SIGSTOP, report it to the user - assume the backend
5508 will handle the SIGSTOP if it should show up later.
5510 Also consider that the attach is complete when we see a
5511 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5512 target extended-remote report it instead of a SIGSTOP
5513 (e.g. gdbserver). We already rely on SIGTRAP being our
5514 signal, so this is no exception.
5516 Also consider that the attach is complete when we see a
5517 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5518 the target to stop all threads of the inferior, in case the
5519 low level attach operation doesn't stop them implicitly. If
5520 they weren't stopped implicitly, then the stub will report a
5521 GDB_SIGNAL_0, meaning: stopped for no particular reason
5522 other than GDB's request. */
5523 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5524 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5525 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5526 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5528 stop_print_frame
= 1;
5530 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5534 /* See if something interesting happened to the non-current thread. If
5535 so, then switch to that thread. */
5536 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5539 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5541 context_switch (ecs
->ptid
);
5543 if (deprecated_context_hook
)
5544 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
5547 /* At this point, get hold of the now-current thread's frame. */
5548 frame
= get_current_frame ();
5549 gdbarch
= get_frame_arch (frame
);
5551 /* Pull the single step breakpoints out of the target. */
5552 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5554 struct regcache
*regcache
;
5555 struct address_space
*aspace
;
5558 regcache
= get_thread_regcache (ecs
->ptid
);
5559 aspace
= get_regcache_aspace (regcache
);
5560 pc
= regcache_read_pc (regcache
);
5562 /* However, before doing so, if this single-step breakpoint was
5563 actually for another thread, set this thread up for moving
5565 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5568 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5572 fprintf_unfiltered (gdb_stdlog
,
5573 "infrun: [%s] hit another thread's "
5574 "single-step breakpoint\n",
5575 target_pid_to_str (ecs
->ptid
));
5577 ecs
->hit_singlestep_breakpoint
= 1;
5584 fprintf_unfiltered (gdb_stdlog
,
5585 "infrun: [%s] hit its "
5586 "single-step breakpoint\n",
5587 target_pid_to_str (ecs
->ptid
));
5591 delete_just_stopped_threads_single_step_breakpoints ();
5593 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5594 && ecs
->event_thread
->control
.trap_expected
5595 && ecs
->event_thread
->stepping_over_watchpoint
)
5596 stopped_by_watchpoint
= 0;
5598 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5600 /* If necessary, step over this watchpoint. We'll be back to display
5602 if (stopped_by_watchpoint
5603 && (target_have_steppable_watchpoint
5604 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5606 /* At this point, we are stopped at an instruction which has
5607 attempted to write to a piece of memory under control of
5608 a watchpoint. The instruction hasn't actually executed
5609 yet. If we were to evaluate the watchpoint expression
5610 now, we would get the old value, and therefore no change
5611 would seem to have occurred.
5613 In order to make watchpoints work `right', we really need
5614 to complete the memory write, and then evaluate the
5615 watchpoint expression. We do this by single-stepping the
5618 It may not be necessary to disable the watchpoint to step over
5619 it. For example, the PA can (with some kernel cooperation)
5620 single step over a watchpoint without disabling the watchpoint.
5622 It is far more common to need to disable a watchpoint to step
5623 the inferior over it. If we have non-steppable watchpoints,
5624 we must disable the current watchpoint; it's simplest to
5625 disable all watchpoints.
5627 Any breakpoint at PC must also be stepped over -- if there's
5628 one, it will have already triggered before the watchpoint
5629 triggered, and we either already reported it to the user, or
5630 it didn't cause a stop and we called keep_going. In either
5631 case, if there was a breakpoint at PC, we must be trying to
5633 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5638 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5639 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5640 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5641 ecs
->event_thread
->control
.stop_step
= 0;
5642 stop_print_frame
= 1;
5643 stopped_by_random_signal
= 0;
5645 /* Hide inlined functions starting here, unless we just performed stepi or
5646 nexti. After stepi and nexti, always show the innermost frame (not any
5647 inline function call sites). */
5648 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5650 struct address_space
*aspace
=
5651 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5653 /* skip_inline_frames is expensive, so we avoid it if we can
5654 determine that the address is one where functions cannot have
5655 been inlined. This improves performance with inferiors that
5656 load a lot of shared libraries, because the solib event
5657 breakpoint is defined as the address of a function (i.e. not
5658 inline). Note that we have to check the previous PC as well
5659 as the current one to catch cases when we have just
5660 single-stepped off a breakpoint prior to reinstating it.
5661 Note that we're assuming that the code we single-step to is
5662 not inline, but that's not definitive: there's nothing
5663 preventing the event breakpoint function from containing
5664 inlined code, and the single-step ending up there. If the
5665 user had set a breakpoint on that inlined code, the missing
5666 skip_inline_frames call would break things. Fortunately
5667 that's an extremely unlikely scenario. */
5668 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5669 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5670 && ecs
->event_thread
->control
.trap_expected
5671 && pc_at_non_inline_function (aspace
,
5672 ecs
->event_thread
->prev_pc
,
5675 skip_inline_frames (ecs
->ptid
);
5677 /* Re-fetch current thread's frame in case that invalidated
5679 frame
= get_current_frame ();
5680 gdbarch
= get_frame_arch (frame
);
5684 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5685 && ecs
->event_thread
->control
.trap_expected
5686 && gdbarch_single_step_through_delay_p (gdbarch
)
5687 && currently_stepping (ecs
->event_thread
))
5689 /* We're trying to step off a breakpoint. Turns out that we're
5690 also on an instruction that needs to be stepped multiple
5691 times before it's been fully executing. E.g., architectures
5692 with a delay slot. It needs to be stepped twice, once for
5693 the instruction and once for the delay slot. */
5694 int step_through_delay
5695 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5697 if (debug_infrun
&& step_through_delay
)
5698 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5699 if (ecs
->event_thread
->control
.step_range_end
== 0
5700 && step_through_delay
)
5702 /* The user issued a continue when stopped at a breakpoint.
5703 Set up for another trap and get out of here. */
5704 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5708 else if (step_through_delay
)
5710 /* The user issued a step when stopped at a breakpoint.
5711 Maybe we should stop, maybe we should not - the delay
5712 slot *might* correspond to a line of source. In any
5713 case, don't decide that here, just set
5714 ecs->stepping_over_breakpoint, making sure we
5715 single-step again before breakpoints are re-inserted. */
5716 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5720 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5721 handles this event. */
5722 ecs
->event_thread
->control
.stop_bpstat
5723 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5724 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5726 /* Following in case break condition called a
5728 stop_print_frame
= 1;
5730 /* This is where we handle "moribund" watchpoints. Unlike
5731 software breakpoints traps, hardware watchpoint traps are
5732 always distinguishable from random traps. If no high-level
5733 watchpoint is associated with the reported stop data address
5734 anymore, then the bpstat does not explain the signal ---
5735 simply make sure to ignore it if `stopped_by_watchpoint' is
5739 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5740 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5742 && stopped_by_watchpoint
)
5743 fprintf_unfiltered (gdb_stdlog
,
5744 "infrun: no user watchpoint explains "
5745 "watchpoint SIGTRAP, ignoring\n");
5747 /* NOTE: cagney/2003-03-29: These checks for a random signal
5748 at one stage in the past included checks for an inferior
5749 function call's call dummy's return breakpoint. The original
5750 comment, that went with the test, read:
5752 ``End of a stack dummy. Some systems (e.g. Sony news) give
5753 another signal besides SIGTRAP, so check here as well as
5756 If someone ever tries to get call dummys on a
5757 non-executable stack to work (where the target would stop
5758 with something like a SIGSEGV), then those tests might need
5759 to be re-instated. Given, however, that the tests were only
5760 enabled when momentary breakpoints were not being used, I
5761 suspect that it won't be the case.
5763 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5764 be necessary for call dummies on a non-executable stack on
5767 /* See if the breakpoints module can explain the signal. */
5769 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5770 ecs
->event_thread
->suspend
.stop_signal
);
5772 /* Maybe this was a trap for a software breakpoint that has since
5774 if (random_signal
&& target_stopped_by_sw_breakpoint ())
5776 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
5778 struct regcache
*regcache
;
5781 /* Re-adjust PC to what the program would see if GDB was not
5783 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
5784 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
5787 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
5789 if (record_full_is_used ())
5790 record_full_gdb_operation_disable_set ();
5792 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
5794 do_cleanups (old_cleanups
);
5799 /* A delayed software breakpoint event. Ignore the trap. */
5801 fprintf_unfiltered (gdb_stdlog
,
5802 "infrun: delayed software breakpoint "
5803 "trap, ignoring\n");
5808 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
5809 has since been removed. */
5810 if (random_signal
&& target_stopped_by_hw_breakpoint ())
5812 /* A delayed hardware breakpoint event. Ignore the trap. */
5814 fprintf_unfiltered (gdb_stdlog
,
5815 "infrun: delayed hardware breakpoint/watchpoint "
5816 "trap, ignoring\n");
5820 /* If not, perhaps stepping/nexting can. */
5822 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5823 && currently_stepping (ecs
->event_thread
));
5825 /* Perhaps the thread hit a single-step breakpoint of _another_
5826 thread. Single-step breakpoints are transparent to the
5827 breakpoints module. */
5829 random_signal
= !ecs
->hit_singlestep_breakpoint
;
5831 /* No? Perhaps we got a moribund watchpoint. */
5833 random_signal
= !stopped_by_watchpoint
;
5835 /* For the program's own signals, act according to
5836 the signal handling tables. */
5840 /* Signal not for debugging purposes. */
5841 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
5842 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
5845 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
5846 gdb_signal_to_symbol_string (stop_signal
));
5848 stopped_by_random_signal
= 1;
5850 /* Always stop on signals if we're either just gaining control
5851 of the program, or the user explicitly requested this thread
5852 to remain stopped. */
5853 if (stop_soon
!= NO_STOP_QUIETLY
5854 || ecs
->event_thread
->stop_requested
5856 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
5862 /* Notify observers the signal has "handle print" set. Note we
5863 returned early above if stopping; normal_stop handles the
5864 printing in that case. */
5865 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
5867 /* The signal table tells us to print about this signal. */
5868 target_terminal_ours_for_output ();
5869 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
5870 target_terminal_inferior ();
5873 /* Clear the signal if it should not be passed. */
5874 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
5875 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5877 if (ecs
->event_thread
->prev_pc
== stop_pc
5878 && ecs
->event_thread
->control
.trap_expected
5879 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5883 /* We were just starting a new sequence, attempting to
5884 single-step off of a breakpoint and expecting a SIGTRAP.
5885 Instead this signal arrives. This signal will take us out
5886 of the stepping range so GDB needs to remember to, when
5887 the signal handler returns, resume stepping off that
5889 /* To simplify things, "continue" is forced to use the same
5890 code paths as single-step - set a breakpoint at the
5891 signal return address and then, once hit, step off that
5894 fprintf_unfiltered (gdb_stdlog
,
5895 "infrun: signal arrived while stepping over "
5898 was_in_line
= step_over_info_valid_p ();
5899 clear_step_over_info ();
5900 insert_hp_step_resume_breakpoint_at_frame (frame
);
5901 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5902 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5903 ecs
->event_thread
->control
.trap_expected
= 0;
5905 if (target_is_non_stop_p ())
5907 /* Either "set non-stop" is "on", or the target is
5908 always in non-stop mode. In this case, we have a bit
5909 more work to do. Resume the current thread, and if
5910 we had paused all threads, restart them while the
5911 signal handler runs. */
5916 restart_threads (ecs
->event_thread
);
5918 else if (debug_infrun
)
5920 fprintf_unfiltered (gdb_stdlog
,
5921 "infrun: no need to restart threads\n");
5926 /* If we were nexting/stepping some other thread, switch to
5927 it, so that we don't continue it, losing control. */
5928 if (!switch_back_to_stepped_thread (ecs
))
5933 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
5934 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
5935 || ecs
->event_thread
->control
.step_range_end
== 1)
5936 && frame_id_eq (get_stack_frame_id (frame
),
5937 ecs
->event_thread
->control
.step_stack_frame_id
)
5938 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5940 /* The inferior is about to take a signal that will take it
5941 out of the single step range. Set a breakpoint at the
5942 current PC (which is presumably where the signal handler
5943 will eventually return) and then allow the inferior to
5946 Note that this is only needed for a signal delivered
5947 while in the single-step range. Nested signals aren't a
5948 problem as they eventually all return. */
5950 fprintf_unfiltered (gdb_stdlog
,
5951 "infrun: signal may take us out of "
5952 "single-step range\n");
5954 clear_step_over_info ();
5955 insert_hp_step_resume_breakpoint_at_frame (frame
);
5956 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5957 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5958 ecs
->event_thread
->control
.trap_expected
= 0;
5963 /* Note: step_resume_breakpoint may be non-NULL. This occures
5964 when either there's a nested signal, or when there's a
5965 pending signal enabled just as the signal handler returns
5966 (leaving the inferior at the step-resume-breakpoint without
5967 actually executing it). Either way continue until the
5968 breakpoint is really hit. */
5970 if (!switch_back_to_stepped_thread (ecs
))
5973 fprintf_unfiltered (gdb_stdlog
,
5974 "infrun: random signal, keep going\n");
5981 process_event_stop_test (ecs
);
5984 /* Come here when we've got some debug event / signal we can explain
5985 (IOW, not a random signal), and test whether it should cause a
5986 stop, or whether we should resume the inferior (transparently).
5987 E.g., could be a breakpoint whose condition evaluates false; we
5988 could be still stepping within the line; etc. */
5991 process_event_stop_test (struct execution_control_state
*ecs
)
5993 struct symtab_and_line stop_pc_sal
;
5994 struct frame_info
*frame
;
5995 struct gdbarch
*gdbarch
;
5996 CORE_ADDR jmp_buf_pc
;
5997 struct bpstat_what what
;
5999 /* Handle cases caused by hitting a breakpoint. */
6001 frame
= get_current_frame ();
6002 gdbarch
= get_frame_arch (frame
);
6004 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6006 if (what
.call_dummy
)
6008 stop_stack_dummy
= what
.call_dummy
;
6011 /* A few breakpoint types have callbacks associated (e.g.,
6012 bp_jit_event). Run them now. */
6013 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6015 /* If we hit an internal event that triggers symbol changes, the
6016 current frame will be invalidated within bpstat_what (e.g., if we
6017 hit an internal solib event). Re-fetch it. */
6018 frame
= get_current_frame ();
6019 gdbarch
= get_frame_arch (frame
);
6021 switch (what
.main_action
)
6023 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6024 /* If we hit the breakpoint at longjmp while stepping, we
6025 install a momentary breakpoint at the target of the
6029 fprintf_unfiltered (gdb_stdlog
,
6030 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6032 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6034 if (what
.is_longjmp
)
6036 struct value
*arg_value
;
6038 /* If we set the longjmp breakpoint via a SystemTap probe,
6039 then use it to extract the arguments. The destination PC
6040 is the third argument to the probe. */
6041 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6044 jmp_buf_pc
= value_as_address (arg_value
);
6045 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6047 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6048 || !gdbarch_get_longjmp_target (gdbarch
,
6049 frame
, &jmp_buf_pc
))
6052 fprintf_unfiltered (gdb_stdlog
,
6053 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6054 "(!gdbarch_get_longjmp_target)\n");
6059 /* Insert a breakpoint at resume address. */
6060 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6063 check_exception_resume (ecs
, frame
);
6067 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6069 struct frame_info
*init_frame
;
6071 /* There are several cases to consider.
6073 1. The initiating frame no longer exists. In this case we
6074 must stop, because the exception or longjmp has gone too
6077 2. The initiating frame exists, and is the same as the
6078 current frame. We stop, because the exception or longjmp
6081 3. The initiating frame exists and is different from the
6082 current frame. This means the exception or longjmp has
6083 been caught beneath the initiating frame, so keep going.
6085 4. longjmp breakpoint has been placed just to protect
6086 against stale dummy frames and user is not interested in
6087 stopping around longjmps. */
6090 fprintf_unfiltered (gdb_stdlog
,
6091 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6093 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6095 delete_exception_resume_breakpoint (ecs
->event_thread
);
6097 if (what
.is_longjmp
)
6099 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6101 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6109 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6113 struct frame_id current_id
6114 = get_frame_id (get_current_frame ());
6115 if (frame_id_eq (current_id
,
6116 ecs
->event_thread
->initiating_frame
))
6118 /* Case 2. Fall through. */
6128 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6130 delete_step_resume_breakpoint (ecs
->event_thread
);
6132 end_stepping_range (ecs
);
6136 case BPSTAT_WHAT_SINGLE
:
6138 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6139 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6140 /* Still need to check other stuff, at least the case where we
6141 are stepping and step out of the right range. */
6144 case BPSTAT_WHAT_STEP_RESUME
:
6146 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6148 delete_step_resume_breakpoint (ecs
->event_thread
);
6149 if (ecs
->event_thread
->control
.proceed_to_finish
6150 && execution_direction
== EXEC_REVERSE
)
6152 struct thread_info
*tp
= ecs
->event_thread
;
6154 /* We are finishing a function in reverse, and just hit the
6155 step-resume breakpoint at the start address of the
6156 function, and we're almost there -- just need to back up
6157 by one more single-step, which should take us back to the
6159 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6163 fill_in_stop_func (gdbarch
, ecs
);
6164 if (stop_pc
== ecs
->stop_func_start
6165 && execution_direction
== EXEC_REVERSE
)
6167 /* We are stepping over a function call in reverse, and just
6168 hit the step-resume breakpoint at the start address of
6169 the function. Go back to single-stepping, which should
6170 take us back to the function call. */
6171 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6177 case BPSTAT_WHAT_STOP_NOISY
:
6179 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6180 stop_print_frame
= 1;
6182 /* Assume the thread stopped for a breapoint. We'll still check
6183 whether a/the breakpoint is there when the thread is next
6185 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6190 case BPSTAT_WHAT_STOP_SILENT
:
6192 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6193 stop_print_frame
= 0;
6195 /* Assume the thread stopped for a breapoint. We'll still check
6196 whether a/the breakpoint is there when the thread is next
6198 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6202 case BPSTAT_WHAT_HP_STEP_RESUME
:
6204 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6206 delete_step_resume_breakpoint (ecs
->event_thread
);
6207 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6209 /* Back when the step-resume breakpoint was inserted, we
6210 were trying to single-step off a breakpoint. Go back to
6212 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6213 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6219 case BPSTAT_WHAT_KEEP_CHECKING
:
6223 /* If we stepped a permanent breakpoint and we had a high priority
6224 step-resume breakpoint for the address we stepped, but we didn't
6225 hit it, then we must have stepped into the signal handler. The
6226 step-resume was only necessary to catch the case of _not_
6227 stepping into the handler, so delete it, and fall through to
6228 checking whether the step finished. */
6229 if (ecs
->event_thread
->stepped_breakpoint
)
6231 struct breakpoint
*sr_bp
6232 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6235 && sr_bp
->loc
->permanent
6236 && sr_bp
->type
== bp_hp_step_resume
6237 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6240 fprintf_unfiltered (gdb_stdlog
,
6241 "infrun: stepped permanent breakpoint, stopped in "
6243 delete_step_resume_breakpoint (ecs
->event_thread
);
6244 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6248 /* We come here if we hit a breakpoint but should not stop for it.
6249 Possibly we also were stepping and should stop for that. So fall
6250 through and test for stepping. But, if not stepping, do not
6253 /* In all-stop mode, if we're currently stepping but have stopped in
6254 some other thread, we need to switch back to the stepped thread. */
6255 if (switch_back_to_stepped_thread (ecs
))
6258 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6261 fprintf_unfiltered (gdb_stdlog
,
6262 "infrun: step-resume breakpoint is inserted\n");
6264 /* Having a step-resume breakpoint overrides anything
6265 else having to do with stepping commands until
6266 that breakpoint is reached. */
6271 if (ecs
->event_thread
->control
.step_range_end
== 0)
6274 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6275 /* Likewise if we aren't even stepping. */
6280 /* Re-fetch current thread's frame in case the code above caused
6281 the frame cache to be re-initialized, making our FRAME variable
6282 a dangling pointer. */
6283 frame
= get_current_frame ();
6284 gdbarch
= get_frame_arch (frame
);
6285 fill_in_stop_func (gdbarch
, ecs
);
6287 /* If stepping through a line, keep going if still within it.
6289 Note that step_range_end is the address of the first instruction
6290 beyond the step range, and NOT the address of the last instruction
6293 Note also that during reverse execution, we may be stepping
6294 through a function epilogue and therefore must detect when
6295 the current-frame changes in the middle of a line. */
6297 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6298 && (execution_direction
!= EXEC_REVERSE
6299 || frame_id_eq (get_frame_id (frame
),
6300 ecs
->event_thread
->control
.step_frame_id
)))
6304 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6305 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6306 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6308 /* Tentatively re-enable range stepping; `resume' disables it if
6309 necessary (e.g., if we're stepping over a breakpoint or we
6310 have software watchpoints). */
6311 ecs
->event_thread
->control
.may_range_step
= 1;
6313 /* When stepping backward, stop at beginning of line range
6314 (unless it's the function entry point, in which case
6315 keep going back to the call point). */
6316 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6317 && stop_pc
!= ecs
->stop_func_start
6318 && execution_direction
== EXEC_REVERSE
)
6319 end_stepping_range (ecs
);
6326 /* We stepped out of the stepping range. */
6328 /* If we are stepping at the source level and entered the runtime
6329 loader dynamic symbol resolution code...
6331 EXEC_FORWARD: we keep on single stepping until we exit the run
6332 time loader code and reach the callee's address.
6334 EXEC_REVERSE: we've already executed the callee (backward), and
6335 the runtime loader code is handled just like any other
6336 undebuggable function call. Now we need only keep stepping
6337 backward through the trampoline code, and that's handled further
6338 down, so there is nothing for us to do here. */
6340 if (execution_direction
!= EXEC_REVERSE
6341 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6342 && in_solib_dynsym_resolve_code (stop_pc
))
6344 CORE_ADDR pc_after_resolver
=
6345 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6348 fprintf_unfiltered (gdb_stdlog
,
6349 "infrun: stepped into dynsym resolve code\n");
6351 if (pc_after_resolver
)
6353 /* Set up a step-resume breakpoint at the address
6354 indicated by SKIP_SOLIB_RESOLVER. */
6355 struct symtab_and_line sr_sal
;
6358 sr_sal
.pc
= pc_after_resolver
;
6359 sr_sal
.pspace
= get_frame_program_space (frame
);
6361 insert_step_resume_breakpoint_at_sal (gdbarch
,
6362 sr_sal
, null_frame_id
);
6369 if (ecs
->event_thread
->control
.step_range_end
!= 1
6370 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6371 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6372 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6375 fprintf_unfiltered (gdb_stdlog
,
6376 "infrun: stepped into signal trampoline\n");
6377 /* The inferior, while doing a "step" or "next", has ended up in
6378 a signal trampoline (either by a signal being delivered or by
6379 the signal handler returning). Just single-step until the
6380 inferior leaves the trampoline (either by calling the handler
6386 /* If we're in the return path from a shared library trampoline,
6387 we want to proceed through the trampoline when stepping. */
6388 /* macro/2012-04-25: This needs to come before the subroutine
6389 call check below as on some targets return trampolines look
6390 like subroutine calls (MIPS16 return thunks). */
6391 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6392 stop_pc
, ecs
->stop_func_name
)
6393 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6395 /* Determine where this trampoline returns. */
6396 CORE_ADDR real_stop_pc
;
6398 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6401 fprintf_unfiltered (gdb_stdlog
,
6402 "infrun: stepped into solib return tramp\n");
6404 /* Only proceed through if we know where it's going. */
6407 /* And put the step-breakpoint there and go until there. */
6408 struct symtab_and_line sr_sal
;
6410 init_sal (&sr_sal
); /* initialize to zeroes */
6411 sr_sal
.pc
= real_stop_pc
;
6412 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6413 sr_sal
.pspace
= get_frame_program_space (frame
);
6415 /* Do not specify what the fp should be when we stop since
6416 on some machines the prologue is where the new fp value
6418 insert_step_resume_breakpoint_at_sal (gdbarch
,
6419 sr_sal
, null_frame_id
);
6421 /* Restart without fiddling with the step ranges or
6428 /* Check for subroutine calls. The check for the current frame
6429 equalling the step ID is not necessary - the check of the
6430 previous frame's ID is sufficient - but it is a common case and
6431 cheaper than checking the previous frame's ID.
6433 NOTE: frame_id_eq will never report two invalid frame IDs as
6434 being equal, so to get into this block, both the current and
6435 previous frame must have valid frame IDs. */
6436 /* The outer_frame_id check is a heuristic to detect stepping
6437 through startup code. If we step over an instruction which
6438 sets the stack pointer from an invalid value to a valid value,
6439 we may detect that as a subroutine call from the mythical
6440 "outermost" function. This could be fixed by marking
6441 outermost frames as !stack_p,code_p,special_p. Then the
6442 initial outermost frame, before sp was valid, would
6443 have code_addr == &_start. See the comment in frame_id_eq
6445 if (!frame_id_eq (get_stack_frame_id (frame
),
6446 ecs
->event_thread
->control
.step_stack_frame_id
)
6447 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6448 ecs
->event_thread
->control
.step_stack_frame_id
)
6449 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6451 || (ecs
->event_thread
->control
.step_start_function
6452 != find_pc_function (stop_pc
)))))
6454 CORE_ADDR real_stop_pc
;
6457 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6459 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6461 /* I presume that step_over_calls is only 0 when we're
6462 supposed to be stepping at the assembly language level
6463 ("stepi"). Just stop. */
6464 /* And this works the same backward as frontward. MVS */
6465 end_stepping_range (ecs
);
6469 /* Reverse stepping through solib trampolines. */
6471 if (execution_direction
== EXEC_REVERSE
6472 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6473 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6474 || (ecs
->stop_func_start
== 0
6475 && in_solib_dynsym_resolve_code (stop_pc
))))
6477 /* Any solib trampoline code can be handled in reverse
6478 by simply continuing to single-step. We have already
6479 executed the solib function (backwards), and a few
6480 steps will take us back through the trampoline to the
6486 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6488 /* We're doing a "next".
6490 Normal (forward) execution: set a breakpoint at the
6491 callee's return address (the address at which the caller
6494 Reverse (backward) execution. set the step-resume
6495 breakpoint at the start of the function that we just
6496 stepped into (backwards), and continue to there. When we
6497 get there, we'll need to single-step back to the caller. */
6499 if (execution_direction
== EXEC_REVERSE
)
6501 /* If we're already at the start of the function, we've either
6502 just stepped backward into a single instruction function,
6503 or stepped back out of a signal handler to the first instruction
6504 of the function. Just keep going, which will single-step back
6506 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6508 struct symtab_and_line sr_sal
;
6510 /* Normal function call return (static or dynamic). */
6512 sr_sal
.pc
= ecs
->stop_func_start
;
6513 sr_sal
.pspace
= get_frame_program_space (frame
);
6514 insert_step_resume_breakpoint_at_sal (gdbarch
,
6515 sr_sal
, null_frame_id
);
6519 insert_step_resume_breakpoint_at_caller (frame
);
6525 /* If we are in a function call trampoline (a stub between the
6526 calling routine and the real function), locate the real
6527 function. That's what tells us (a) whether we want to step
6528 into it at all, and (b) what prologue we want to run to the
6529 end of, if we do step into it. */
6530 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6531 if (real_stop_pc
== 0)
6532 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6533 if (real_stop_pc
!= 0)
6534 ecs
->stop_func_start
= real_stop_pc
;
6536 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6538 struct symtab_and_line sr_sal
;
6541 sr_sal
.pc
= ecs
->stop_func_start
;
6542 sr_sal
.pspace
= get_frame_program_space (frame
);
6544 insert_step_resume_breakpoint_at_sal (gdbarch
,
6545 sr_sal
, null_frame_id
);
6550 /* If we have line number information for the function we are
6551 thinking of stepping into and the function isn't on the skip
6554 If there are several symtabs at that PC (e.g. with include
6555 files), just want to know whether *any* of them have line
6556 numbers. find_pc_line handles this. */
6558 struct symtab_and_line tmp_sal
;
6560 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6561 if (tmp_sal
.line
!= 0
6562 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6565 if (execution_direction
== EXEC_REVERSE
)
6566 handle_step_into_function_backward (gdbarch
, ecs
);
6568 handle_step_into_function (gdbarch
, ecs
);
6573 /* If we have no line number and the step-stop-if-no-debug is
6574 set, we stop the step so that the user has a chance to switch
6575 in assembly mode. */
6576 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6577 && step_stop_if_no_debug
)
6579 end_stepping_range (ecs
);
6583 if (execution_direction
== EXEC_REVERSE
)
6585 /* If we're already at the start of the function, we've either just
6586 stepped backward into a single instruction function without line
6587 number info, or stepped back out of a signal handler to the first
6588 instruction of the function without line number info. Just keep
6589 going, which will single-step back to the caller. */
6590 if (ecs
->stop_func_start
!= stop_pc
)
6592 /* Set a breakpoint at callee's start address.
6593 From there we can step once and be back in the caller. */
6594 struct symtab_and_line sr_sal
;
6597 sr_sal
.pc
= ecs
->stop_func_start
;
6598 sr_sal
.pspace
= get_frame_program_space (frame
);
6599 insert_step_resume_breakpoint_at_sal (gdbarch
,
6600 sr_sal
, null_frame_id
);
6604 /* Set a breakpoint at callee's return address (the address
6605 at which the caller will resume). */
6606 insert_step_resume_breakpoint_at_caller (frame
);
6612 /* Reverse stepping through solib trampolines. */
6614 if (execution_direction
== EXEC_REVERSE
6615 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6617 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6618 || (ecs
->stop_func_start
== 0
6619 && in_solib_dynsym_resolve_code (stop_pc
)))
6621 /* Any solib trampoline code can be handled in reverse
6622 by simply continuing to single-step. We have already
6623 executed the solib function (backwards), and a few
6624 steps will take us back through the trampoline to the
6629 else if (in_solib_dynsym_resolve_code (stop_pc
))
6631 /* Stepped backward into the solib dynsym resolver.
6632 Set a breakpoint at its start and continue, then
6633 one more step will take us out. */
6634 struct symtab_and_line sr_sal
;
6637 sr_sal
.pc
= ecs
->stop_func_start
;
6638 sr_sal
.pspace
= get_frame_program_space (frame
);
6639 insert_step_resume_breakpoint_at_sal (gdbarch
,
6640 sr_sal
, null_frame_id
);
6646 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6648 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6649 the trampoline processing logic, however, there are some trampolines
6650 that have no names, so we should do trampoline handling first. */
6651 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6652 && ecs
->stop_func_name
== NULL
6653 && stop_pc_sal
.line
== 0)
6656 fprintf_unfiltered (gdb_stdlog
,
6657 "infrun: stepped into undebuggable function\n");
6659 /* The inferior just stepped into, or returned to, an
6660 undebuggable function (where there is no debugging information
6661 and no line number corresponding to the address where the
6662 inferior stopped). Since we want to skip this kind of code,
6663 we keep going until the inferior returns from this
6664 function - unless the user has asked us not to (via
6665 set step-mode) or we no longer know how to get back
6666 to the call site. */
6667 if (step_stop_if_no_debug
6668 || !frame_id_p (frame_unwind_caller_id (frame
)))
6670 /* If we have no line number and the step-stop-if-no-debug
6671 is set, we stop the step so that the user has a chance to
6672 switch in assembly mode. */
6673 end_stepping_range (ecs
);
6678 /* Set a breakpoint at callee's return address (the address
6679 at which the caller will resume). */
6680 insert_step_resume_breakpoint_at_caller (frame
);
6686 if (ecs
->event_thread
->control
.step_range_end
== 1)
6688 /* It is stepi or nexti. We always want to stop stepping after
6691 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6692 end_stepping_range (ecs
);
6696 if (stop_pc_sal
.line
== 0)
6698 /* We have no line number information. That means to stop
6699 stepping (does this always happen right after one instruction,
6700 when we do "s" in a function with no line numbers,
6701 or can this happen as a result of a return or longjmp?). */
6703 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6704 end_stepping_range (ecs
);
6708 /* Look for "calls" to inlined functions, part one. If the inline
6709 frame machinery detected some skipped call sites, we have entered
6710 a new inline function. */
6712 if (frame_id_eq (get_frame_id (get_current_frame ()),
6713 ecs
->event_thread
->control
.step_frame_id
)
6714 && inline_skipped_frames (ecs
->ptid
))
6716 struct symtab_and_line call_sal
;
6719 fprintf_unfiltered (gdb_stdlog
,
6720 "infrun: stepped into inlined function\n");
6722 find_frame_sal (get_current_frame (), &call_sal
);
6724 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6726 /* For "step", we're going to stop. But if the call site
6727 for this inlined function is on the same source line as
6728 we were previously stepping, go down into the function
6729 first. Otherwise stop at the call site. */
6731 if (call_sal
.line
== ecs
->event_thread
->current_line
6732 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6733 step_into_inline_frame (ecs
->ptid
);
6735 end_stepping_range (ecs
);
6740 /* For "next", we should stop at the call site if it is on a
6741 different source line. Otherwise continue through the
6742 inlined function. */
6743 if (call_sal
.line
== ecs
->event_thread
->current_line
6744 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6747 end_stepping_range (ecs
);
6752 /* Look for "calls" to inlined functions, part two. If we are still
6753 in the same real function we were stepping through, but we have
6754 to go further up to find the exact frame ID, we are stepping
6755 through a more inlined call beyond its call site. */
6757 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6758 && !frame_id_eq (get_frame_id (get_current_frame ()),
6759 ecs
->event_thread
->control
.step_frame_id
)
6760 && stepped_in_from (get_current_frame (),
6761 ecs
->event_thread
->control
.step_frame_id
))
6764 fprintf_unfiltered (gdb_stdlog
,
6765 "infrun: stepping through inlined function\n");
6767 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6770 end_stepping_range (ecs
);
6774 if ((stop_pc
== stop_pc_sal
.pc
)
6775 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6776 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6778 /* We are at the start of a different line. So stop. Note that
6779 we don't stop if we step into the middle of a different line.
6780 That is said to make things like for (;;) statements work
6783 fprintf_unfiltered (gdb_stdlog
,
6784 "infrun: stepped to a different line\n");
6785 end_stepping_range (ecs
);
6789 /* We aren't done stepping.
6791 Optimize by setting the stepping range to the line.
6792 (We might not be in the original line, but if we entered a
6793 new line in mid-statement, we continue stepping. This makes
6794 things like for(;;) statements work better.) */
6796 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
6797 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
6798 ecs
->event_thread
->control
.may_range_step
= 1;
6799 set_step_info (frame
, stop_pc_sal
);
6802 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
6806 /* In all-stop mode, if we're currently stepping but have stopped in
6807 some other thread, we may need to switch back to the stepped
6808 thread. Returns true we set the inferior running, false if we left
6809 it stopped (and the event needs further processing). */
6812 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
6814 if (!target_is_non_stop_p ())
6816 struct thread_info
*tp
;
6817 struct thread_info
*stepping_thread
;
6819 /* If any thread is blocked on some internal breakpoint, and we
6820 simply need to step over that breakpoint to get it going
6821 again, do that first. */
6823 /* However, if we see an event for the stepping thread, then we
6824 know all other threads have been moved past their breakpoints
6825 already. Let the caller check whether the step is finished,
6826 etc., before deciding to move it past a breakpoint. */
6827 if (ecs
->event_thread
->control
.step_range_end
!= 0)
6830 /* Check if the current thread is blocked on an incomplete
6831 step-over, interrupted by a random signal. */
6832 if (ecs
->event_thread
->control
.trap_expected
6833 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6837 fprintf_unfiltered (gdb_stdlog
,
6838 "infrun: need to finish step-over of [%s]\n",
6839 target_pid_to_str (ecs
->event_thread
->ptid
));
6845 /* Check if the current thread is blocked by a single-step
6846 breakpoint of another thread. */
6847 if (ecs
->hit_singlestep_breakpoint
)
6851 fprintf_unfiltered (gdb_stdlog
,
6852 "infrun: need to step [%s] over single-step "
6854 target_pid_to_str (ecs
->ptid
));
6860 /* If this thread needs yet another step-over (e.g., stepping
6861 through a delay slot), do it first before moving on to
6863 if (thread_still_needs_step_over (ecs
->event_thread
))
6867 fprintf_unfiltered (gdb_stdlog
,
6868 "infrun: thread [%s] still needs step-over\n",
6869 target_pid_to_str (ecs
->event_thread
->ptid
));
6875 /* If scheduler locking applies even if not stepping, there's no
6876 need to walk over threads. Above we've checked whether the
6877 current thread is stepping. If some other thread not the
6878 event thread is stepping, then it must be that scheduler
6879 locking is not in effect. */
6880 if (schedlock_applies (ecs
->event_thread
))
6883 /* Otherwise, we no longer expect a trap in the current thread.
6884 Clear the trap_expected flag before switching back -- this is
6885 what keep_going does as well, if we call it. */
6886 ecs
->event_thread
->control
.trap_expected
= 0;
6888 /* Likewise, clear the signal if it should not be passed. */
6889 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6890 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6892 /* Do all pending step-overs before actually proceeding with
6894 if (start_step_over ())
6896 prepare_to_wait (ecs
);
6900 /* Look for the stepping/nexting thread. */
6901 stepping_thread
= NULL
;
6903 ALL_NON_EXITED_THREADS (tp
)
6905 /* Ignore threads of processes the caller is not
6908 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
6911 /* When stepping over a breakpoint, we lock all threads
6912 except the one that needs to move past the breakpoint.
6913 If a non-event thread has this set, the "incomplete
6914 step-over" check above should have caught it earlier. */
6915 if (tp
->control
.trap_expected
)
6917 internal_error (__FILE__
, __LINE__
,
6918 "[%s] has inconsistent state: "
6919 "trap_expected=%d\n",
6920 target_pid_to_str (tp
->ptid
),
6921 tp
->control
.trap_expected
);
6924 /* Did we find the stepping thread? */
6925 if (tp
->control
.step_range_end
)
6927 /* Yep. There should only one though. */
6928 gdb_assert (stepping_thread
== NULL
);
6930 /* The event thread is handled at the top, before we
6932 gdb_assert (tp
!= ecs
->event_thread
);
6934 /* If some thread other than the event thread is
6935 stepping, then scheduler locking can't be in effect,
6936 otherwise we wouldn't have resumed the current event
6937 thread in the first place. */
6938 gdb_assert (!schedlock_applies (tp
));
6940 stepping_thread
= tp
;
6944 if (stepping_thread
!= NULL
)
6947 fprintf_unfiltered (gdb_stdlog
,
6948 "infrun: switching back to stepped thread\n");
6950 if (keep_going_stepped_thread (stepping_thread
))
6952 prepare_to_wait (ecs
);
6961 /* Set a previously stepped thread back to stepping. Returns true on
6962 success, false if the resume is not possible (e.g., the thread
6966 keep_going_stepped_thread (struct thread_info
*tp
)
6968 struct frame_info
*frame
;
6969 struct gdbarch
*gdbarch
;
6970 struct execution_control_state ecss
;
6971 struct execution_control_state
*ecs
= &ecss
;
6973 /* If the stepping thread exited, then don't try to switch back and
6974 resume it, which could fail in several different ways depending
6975 on the target. Instead, just keep going.
6977 We can find a stepping dead thread in the thread list in two
6980 - The target supports thread exit events, and when the target
6981 tries to delete the thread from the thread list, inferior_ptid
6982 pointed at the exiting thread. In such case, calling
6983 delete_thread does not really remove the thread from the list;
6984 instead, the thread is left listed, with 'exited' state.
6986 - The target's debug interface does not support thread exit
6987 events, and so we have no idea whatsoever if the previously
6988 stepping thread is still alive. For that reason, we need to
6989 synchronously query the target now. */
6991 if (is_exited (tp
->ptid
)
6992 || !target_thread_alive (tp
->ptid
))
6995 fprintf_unfiltered (gdb_stdlog
,
6996 "infrun: not resuming previously "
6997 "stepped thread, it has vanished\n");
6999 delete_thread (tp
->ptid
);
7004 fprintf_unfiltered (gdb_stdlog
,
7005 "infrun: resuming previously stepped thread\n");
7007 reset_ecs (ecs
, tp
);
7008 switch_to_thread (tp
->ptid
);
7010 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7011 frame
= get_current_frame ();
7012 gdbarch
= get_frame_arch (frame
);
7014 /* If the PC of the thread we were trying to single-step has
7015 changed, then that thread has trapped or been signaled, but the
7016 event has not been reported to GDB yet. Re-poll the target
7017 looking for this particular thread's event (i.e. temporarily
7018 enable schedlock) by:
7020 - setting a break at the current PC
7021 - resuming that particular thread, only (by setting trap
7024 This prevents us continuously moving the single-step breakpoint
7025 forward, one instruction at a time, overstepping. */
7027 if (stop_pc
!= tp
->prev_pc
)
7032 fprintf_unfiltered (gdb_stdlog
,
7033 "infrun: expected thread advanced also (%s -> %s)\n",
7034 paddress (target_gdbarch (), tp
->prev_pc
),
7035 paddress (target_gdbarch (), stop_pc
));
7037 /* Clear the info of the previous step-over, as it's no longer
7038 valid (if the thread was trying to step over a breakpoint, it
7039 has already succeeded). It's what keep_going would do too,
7040 if we called it. Do this before trying to insert the sss
7041 breakpoint, otherwise if we were previously trying to step
7042 over this exact address in another thread, the breakpoint is
7044 clear_step_over_info ();
7045 tp
->control
.trap_expected
= 0;
7047 insert_single_step_breakpoint (get_frame_arch (frame
),
7048 get_frame_address_space (frame
),
7052 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7053 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7058 fprintf_unfiltered (gdb_stdlog
,
7059 "infrun: expected thread still hasn't advanced\n");
7061 keep_going_pass_signal (ecs
);
7066 /* Is thread TP in the middle of (software or hardware)
7067 single-stepping? (Note the result of this function must never be
7068 passed directly as target_resume's STEP parameter.) */
7071 currently_stepping (struct thread_info
*tp
)
7073 return ((tp
->control
.step_range_end
7074 && tp
->control
.step_resume_breakpoint
== NULL
)
7075 || tp
->control
.trap_expected
7076 || tp
->stepped_breakpoint
7077 || bpstat_should_step ());
7080 /* Inferior has stepped into a subroutine call with source code that
7081 we should not step over. Do step to the first line of code in
7085 handle_step_into_function (struct gdbarch
*gdbarch
,
7086 struct execution_control_state
*ecs
)
7088 struct compunit_symtab
*cust
;
7089 struct symtab_and_line stop_func_sal
, sr_sal
;
7091 fill_in_stop_func (gdbarch
, ecs
);
7093 cust
= find_pc_compunit_symtab (stop_pc
);
7094 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7095 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7096 ecs
->stop_func_start
);
7098 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7099 /* Use the step_resume_break to step until the end of the prologue,
7100 even if that involves jumps (as it seems to on the vax under
7102 /* If the prologue ends in the middle of a source line, continue to
7103 the end of that source line (if it is still within the function).
7104 Otherwise, just go to end of prologue. */
7105 if (stop_func_sal
.end
7106 && stop_func_sal
.pc
!= ecs
->stop_func_start
7107 && stop_func_sal
.end
< ecs
->stop_func_end
)
7108 ecs
->stop_func_start
= stop_func_sal
.end
;
7110 /* Architectures which require breakpoint adjustment might not be able
7111 to place a breakpoint at the computed address. If so, the test
7112 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7113 ecs->stop_func_start to an address at which a breakpoint may be
7114 legitimately placed.
7116 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7117 made, GDB will enter an infinite loop when stepping through
7118 optimized code consisting of VLIW instructions which contain
7119 subinstructions corresponding to different source lines. On
7120 FR-V, it's not permitted to place a breakpoint on any but the
7121 first subinstruction of a VLIW instruction. When a breakpoint is
7122 set, GDB will adjust the breakpoint address to the beginning of
7123 the VLIW instruction. Thus, we need to make the corresponding
7124 adjustment here when computing the stop address. */
7126 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7128 ecs
->stop_func_start
7129 = gdbarch_adjust_breakpoint_address (gdbarch
,
7130 ecs
->stop_func_start
);
7133 if (ecs
->stop_func_start
== stop_pc
)
7135 /* We are already there: stop now. */
7136 end_stepping_range (ecs
);
7141 /* Put the step-breakpoint there and go until there. */
7142 init_sal (&sr_sal
); /* initialize to zeroes */
7143 sr_sal
.pc
= ecs
->stop_func_start
;
7144 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7145 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7147 /* Do not specify what the fp should be when we stop since on
7148 some machines the prologue is where the new fp value is
7150 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7152 /* And make sure stepping stops right away then. */
7153 ecs
->event_thread
->control
.step_range_end
7154 = ecs
->event_thread
->control
.step_range_start
;
7159 /* Inferior has stepped backward into a subroutine call with source
7160 code that we should not step over. Do step to the beginning of the
7161 last line of code in it. */
7164 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7165 struct execution_control_state
*ecs
)
7167 struct compunit_symtab
*cust
;
7168 struct symtab_and_line stop_func_sal
;
7170 fill_in_stop_func (gdbarch
, ecs
);
7172 cust
= find_pc_compunit_symtab (stop_pc
);
7173 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7174 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7175 ecs
->stop_func_start
);
7177 stop_func_sal
= find_pc_line (stop_pc
, 0);
7179 /* OK, we're just going to keep stepping here. */
7180 if (stop_func_sal
.pc
== stop_pc
)
7182 /* We're there already. Just stop stepping now. */
7183 end_stepping_range (ecs
);
7187 /* Else just reset the step range and keep going.
7188 No step-resume breakpoint, they don't work for
7189 epilogues, which can have multiple entry paths. */
7190 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7191 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7197 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7198 This is used to both functions and to skip over code. */
7201 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7202 struct symtab_and_line sr_sal
,
7203 struct frame_id sr_id
,
7204 enum bptype sr_type
)
7206 /* There should never be more than one step-resume or longjmp-resume
7207 breakpoint per thread, so we should never be setting a new
7208 step_resume_breakpoint when one is already active. */
7209 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7210 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7213 fprintf_unfiltered (gdb_stdlog
,
7214 "infrun: inserting step-resume breakpoint at %s\n",
7215 paddress (gdbarch
, sr_sal
.pc
));
7217 inferior_thread ()->control
.step_resume_breakpoint
7218 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7222 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7223 struct symtab_and_line sr_sal
,
7224 struct frame_id sr_id
)
7226 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7231 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7232 This is used to skip a potential signal handler.
7234 This is called with the interrupted function's frame. The signal
7235 handler, when it returns, will resume the interrupted function at
7239 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7241 struct symtab_and_line sr_sal
;
7242 struct gdbarch
*gdbarch
;
7244 gdb_assert (return_frame
!= NULL
);
7245 init_sal (&sr_sal
); /* initialize to zeros */
7247 gdbarch
= get_frame_arch (return_frame
);
7248 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7249 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7250 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7252 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7253 get_stack_frame_id (return_frame
),
7257 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7258 is used to skip a function after stepping into it (for "next" or if
7259 the called function has no debugging information).
7261 The current function has almost always been reached by single
7262 stepping a call or return instruction. NEXT_FRAME belongs to the
7263 current function, and the breakpoint will be set at the caller's
7266 This is a separate function rather than reusing
7267 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7268 get_prev_frame, which may stop prematurely (see the implementation
7269 of frame_unwind_caller_id for an example). */
7272 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7274 struct symtab_and_line sr_sal
;
7275 struct gdbarch
*gdbarch
;
7277 /* We shouldn't have gotten here if we don't know where the call site
7279 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7281 init_sal (&sr_sal
); /* initialize to zeros */
7283 gdbarch
= frame_unwind_caller_arch (next_frame
);
7284 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7285 frame_unwind_caller_pc (next_frame
));
7286 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7287 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7289 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7290 frame_unwind_caller_id (next_frame
));
7293 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7294 new breakpoint at the target of a jmp_buf. The handling of
7295 longjmp-resume uses the same mechanisms used for handling
7296 "step-resume" breakpoints. */
7299 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7301 /* There should never be more than one longjmp-resume breakpoint per
7302 thread, so we should never be setting a new
7303 longjmp_resume_breakpoint when one is already active. */
7304 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7307 fprintf_unfiltered (gdb_stdlog
,
7308 "infrun: inserting longjmp-resume breakpoint at %s\n",
7309 paddress (gdbarch
, pc
));
7311 inferior_thread ()->control
.exception_resume_breakpoint
=
7312 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7315 /* Insert an exception resume breakpoint. TP is the thread throwing
7316 the exception. The block B is the block of the unwinder debug hook
7317 function. FRAME is the frame corresponding to the call to this
7318 function. SYM is the symbol of the function argument holding the
7319 target PC of the exception. */
7322 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7323 const struct block
*b
,
7324 struct frame_info
*frame
,
7329 struct block_symbol vsym
;
7330 struct value
*value
;
7332 struct breakpoint
*bp
;
7334 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
7335 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7336 /* If the value was optimized out, revert to the old behavior. */
7337 if (! value_optimized_out (value
))
7339 handler
= value_as_address (value
);
7342 fprintf_unfiltered (gdb_stdlog
,
7343 "infrun: exception resume at %lx\n",
7344 (unsigned long) handler
);
7346 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7347 handler
, bp_exception_resume
);
7349 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7352 bp
->thread
= tp
->num
;
7353 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7356 CATCH (e
, RETURN_MASK_ERROR
)
7358 /* We want to ignore errors here. */
7363 /* A helper for check_exception_resume that sets an
7364 exception-breakpoint based on a SystemTap probe. */
7367 insert_exception_resume_from_probe (struct thread_info
*tp
,
7368 const struct bound_probe
*probe
,
7369 struct frame_info
*frame
)
7371 struct value
*arg_value
;
7373 struct breakpoint
*bp
;
7375 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7379 handler
= value_as_address (arg_value
);
7382 fprintf_unfiltered (gdb_stdlog
,
7383 "infrun: exception resume at %s\n",
7384 paddress (get_objfile_arch (probe
->objfile
),
7387 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7388 handler
, bp_exception_resume
);
7389 bp
->thread
= tp
->num
;
7390 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7393 /* This is called when an exception has been intercepted. Check to
7394 see whether the exception's destination is of interest, and if so,
7395 set an exception resume breakpoint there. */
7398 check_exception_resume (struct execution_control_state
*ecs
,
7399 struct frame_info
*frame
)
7401 struct bound_probe probe
;
7402 struct symbol
*func
;
7404 /* First see if this exception unwinding breakpoint was set via a
7405 SystemTap probe point. If so, the probe has two arguments: the
7406 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7407 set a breakpoint there. */
7408 probe
= find_probe_by_pc (get_frame_pc (frame
));
7411 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7415 func
= get_frame_function (frame
);
7421 const struct block
*b
;
7422 struct block_iterator iter
;
7426 /* The exception breakpoint is a thread-specific breakpoint on
7427 the unwinder's debug hook, declared as:
7429 void _Unwind_DebugHook (void *cfa, void *handler);
7431 The CFA argument indicates the frame to which control is
7432 about to be transferred. HANDLER is the destination PC.
7434 We ignore the CFA and set a temporary breakpoint at HANDLER.
7435 This is not extremely efficient but it avoids issues in gdb
7436 with computing the DWARF CFA, and it also works even in weird
7437 cases such as throwing an exception from inside a signal
7440 b
= SYMBOL_BLOCK_VALUE (func
);
7441 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7443 if (!SYMBOL_IS_ARGUMENT (sym
))
7450 insert_exception_resume_breakpoint (ecs
->event_thread
,
7456 CATCH (e
, RETURN_MASK_ERROR
)
7463 stop_waiting (struct execution_control_state
*ecs
)
7466 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7468 clear_step_over_info ();
7470 /* Let callers know we don't want to wait for the inferior anymore. */
7471 ecs
->wait_some_more
= 0;
7473 /* If all-stop, but the target is always in non-stop mode, stop all
7474 threads now that we're presenting the stop to the user. */
7475 if (!non_stop
&& target_is_non_stop_p ())
7476 stop_all_threads ();
7479 /* Like keep_going, but passes the signal to the inferior, even if the
7480 signal is set to nopass. */
7483 keep_going_pass_signal (struct execution_control_state
*ecs
)
7485 /* Make sure normal_stop is called if we get a QUIT handled before
7487 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
7489 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7490 gdb_assert (!ecs
->event_thread
->resumed
);
7492 /* Save the pc before execution, to compare with pc after stop. */
7493 ecs
->event_thread
->prev_pc
7494 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7496 if (ecs
->event_thread
->control
.trap_expected
)
7498 struct thread_info
*tp
= ecs
->event_thread
;
7501 fprintf_unfiltered (gdb_stdlog
,
7502 "infrun: %s has trap_expected set, "
7503 "resuming to collect trap\n",
7504 target_pid_to_str (tp
->ptid
));
7506 /* We haven't yet gotten our trap, and either: intercepted a
7507 non-signal event (e.g., a fork); or took a signal which we
7508 are supposed to pass through to the inferior. Simply
7510 discard_cleanups (old_cleanups
);
7511 resume (ecs
->event_thread
->suspend
.stop_signal
);
7513 else if (step_over_info_valid_p ())
7515 /* Another thread is stepping over a breakpoint in-line. If
7516 this thread needs a step-over too, queue the request. In
7517 either case, this resume must be deferred for later. */
7518 struct thread_info
*tp
= ecs
->event_thread
;
7520 if (ecs
->hit_singlestep_breakpoint
7521 || thread_still_needs_step_over (tp
))
7524 fprintf_unfiltered (gdb_stdlog
,
7525 "infrun: step-over already in progress: "
7526 "step-over for %s deferred\n",
7527 target_pid_to_str (tp
->ptid
));
7528 thread_step_over_chain_enqueue (tp
);
7533 fprintf_unfiltered (gdb_stdlog
,
7534 "infrun: step-over in progress: "
7535 "resume of %s deferred\n",
7536 target_pid_to_str (tp
->ptid
));
7539 discard_cleanups (old_cleanups
);
7543 struct regcache
*regcache
= get_current_regcache ();
7546 enum step_over_what step_what
;
7548 /* Either the trap was not expected, but we are continuing
7549 anyway (if we got a signal, the user asked it be passed to
7552 We got our expected trap, but decided we should resume from
7555 We're going to run this baby now!
7557 Note that insert_breakpoints won't try to re-insert
7558 already inserted breakpoints. Therefore, we don't
7559 care if breakpoints were already inserted, or not. */
7561 /* If we need to step over a breakpoint, and we're not using
7562 displaced stepping to do so, insert all breakpoints
7563 (watchpoints, etc.) but the one we're stepping over, step one
7564 instruction, and then re-insert the breakpoint when that step
7567 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7569 remove_bp
= (ecs
->hit_singlestep_breakpoint
7570 || (step_what
& STEP_OVER_BREAKPOINT
));
7571 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7573 /* We can't use displaced stepping if we need to step past a
7574 watchpoint. The instruction copied to the scratch pad would
7575 still trigger the watchpoint. */
7577 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7579 set_step_over_info (get_regcache_aspace (regcache
),
7580 regcache_read_pc (regcache
), remove_wps
);
7582 else if (remove_wps
)
7583 set_step_over_info (NULL
, 0, remove_wps
);
7585 /* If we now need to do an in-line step-over, we need to stop
7586 all other threads. Note this must be done before
7587 insert_breakpoints below, because that removes the breakpoint
7588 we're about to step over, otherwise other threads could miss
7590 if (step_over_info_valid_p () && target_is_non_stop_p ())
7591 stop_all_threads ();
7593 /* Stop stepping if inserting breakpoints fails. */
7596 insert_breakpoints ();
7598 CATCH (e
, RETURN_MASK_ERROR
)
7600 exception_print (gdb_stderr
, e
);
7602 discard_cleanups (old_cleanups
);
7607 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7609 discard_cleanups (old_cleanups
);
7610 resume (ecs
->event_thread
->suspend
.stop_signal
);
7613 prepare_to_wait (ecs
);
7616 /* Called when we should continue running the inferior, because the
7617 current event doesn't cause a user visible stop. This does the
7618 resuming part; waiting for the next event is done elsewhere. */
7621 keep_going (struct execution_control_state
*ecs
)
7623 if (ecs
->event_thread
->control
.trap_expected
7624 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7625 ecs
->event_thread
->control
.trap_expected
= 0;
7627 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7628 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7629 keep_going_pass_signal (ecs
);
7632 /* This function normally comes after a resume, before
7633 handle_inferior_event exits. It takes care of any last bits of
7634 housekeeping, and sets the all-important wait_some_more flag. */
7637 prepare_to_wait (struct execution_control_state
*ecs
)
7640 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7642 ecs
->wait_some_more
= 1;
7644 if (!target_is_async_p ())
7645 mark_infrun_async_event_handler ();
7648 /* We are done with the step range of a step/next/si/ni command.
7649 Called once for each n of a "step n" operation. */
7652 end_stepping_range (struct execution_control_state
*ecs
)
7654 ecs
->event_thread
->control
.stop_step
= 1;
7658 /* Several print_*_reason functions to print why the inferior has stopped.
7659 We always print something when the inferior exits, or receives a signal.
7660 The rest of the cases are dealt with later on in normal_stop and
7661 print_it_typical. Ideally there should be a call to one of these
7662 print_*_reason functions functions from handle_inferior_event each time
7663 stop_waiting is called.
7665 Note that we don't call these directly, instead we delegate that to
7666 the interpreters, through observers. Interpreters then call these
7667 with whatever uiout is right. */
7670 print_end_stepping_range_reason (struct ui_out
*uiout
)
7672 /* For CLI-like interpreters, print nothing. */
7674 if (ui_out_is_mi_like_p (uiout
))
7676 ui_out_field_string (uiout
, "reason",
7677 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7682 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7684 annotate_signalled ();
7685 if (ui_out_is_mi_like_p (uiout
))
7687 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7688 ui_out_text (uiout
, "\nProgram terminated with signal ");
7689 annotate_signal_name ();
7690 ui_out_field_string (uiout
, "signal-name",
7691 gdb_signal_to_name (siggnal
));
7692 annotate_signal_name_end ();
7693 ui_out_text (uiout
, ", ");
7694 annotate_signal_string ();
7695 ui_out_field_string (uiout
, "signal-meaning",
7696 gdb_signal_to_string (siggnal
));
7697 annotate_signal_string_end ();
7698 ui_out_text (uiout
, ".\n");
7699 ui_out_text (uiout
, "The program no longer exists.\n");
7703 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7705 struct inferior
*inf
= current_inferior ();
7706 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7708 annotate_exited (exitstatus
);
7711 if (ui_out_is_mi_like_p (uiout
))
7712 ui_out_field_string (uiout
, "reason",
7713 async_reason_lookup (EXEC_ASYNC_EXITED
));
7714 ui_out_text (uiout
, "[Inferior ");
7715 ui_out_text (uiout
, plongest (inf
->num
));
7716 ui_out_text (uiout
, " (");
7717 ui_out_text (uiout
, pidstr
);
7718 ui_out_text (uiout
, ") exited with code ");
7719 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
7720 ui_out_text (uiout
, "]\n");
7724 if (ui_out_is_mi_like_p (uiout
))
7726 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7727 ui_out_text (uiout
, "[Inferior ");
7728 ui_out_text (uiout
, plongest (inf
->num
));
7729 ui_out_text (uiout
, " (");
7730 ui_out_text (uiout
, pidstr
);
7731 ui_out_text (uiout
, ") exited normally]\n");
7736 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7740 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
7742 struct thread_info
*t
= inferior_thread ();
7744 ui_out_text (uiout
, "\n[");
7745 ui_out_field_string (uiout
, "thread-name",
7746 target_pid_to_str (t
->ptid
));
7747 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
7748 ui_out_text (uiout
, " stopped");
7752 ui_out_text (uiout
, "\nProgram received signal ");
7753 annotate_signal_name ();
7754 if (ui_out_is_mi_like_p (uiout
))
7756 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
7757 ui_out_field_string (uiout
, "signal-name",
7758 gdb_signal_to_name (siggnal
));
7759 annotate_signal_name_end ();
7760 ui_out_text (uiout
, ", ");
7761 annotate_signal_string ();
7762 ui_out_field_string (uiout
, "signal-meaning",
7763 gdb_signal_to_string (siggnal
));
7764 annotate_signal_string_end ();
7766 ui_out_text (uiout
, ".\n");
7770 print_no_history_reason (struct ui_out
*uiout
)
7772 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
7775 /* Print current location without a level number, if we have changed
7776 functions or hit a breakpoint. Print source line if we have one.
7777 bpstat_print contains the logic deciding in detail what to print,
7778 based on the event(s) that just occurred. */
7781 print_stop_location (struct target_waitstatus
*ws
)
7784 enum print_what source_flag
;
7785 int do_frame_printing
= 1;
7786 struct thread_info
*tp
= inferior_thread ();
7788 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
7792 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
7793 should) carry around the function and does (or should) use
7794 that when doing a frame comparison. */
7795 if (tp
->control
.stop_step
7796 && frame_id_eq (tp
->control
.step_frame_id
,
7797 get_frame_id (get_current_frame ()))
7798 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
7800 /* Finished step, just print source line. */
7801 source_flag
= SRC_LINE
;
7805 /* Print location and source line. */
7806 source_flag
= SRC_AND_LOC
;
7809 case PRINT_SRC_AND_LOC
:
7810 /* Print location and source line. */
7811 source_flag
= SRC_AND_LOC
;
7813 case PRINT_SRC_ONLY
:
7814 source_flag
= SRC_LINE
;
7817 /* Something bogus. */
7818 source_flag
= SRC_LINE
;
7819 do_frame_printing
= 0;
7822 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
7825 /* The behavior of this routine with respect to the source
7827 SRC_LINE: Print only source line
7828 LOCATION: Print only location
7829 SRC_AND_LOC: Print location and source line. */
7830 if (do_frame_printing
)
7831 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
7834 /* Cleanup that restores a previous current uiout. */
7837 restore_current_uiout_cleanup (void *arg
)
7839 struct ui_out
*saved_uiout
= (struct ui_out
*) arg
;
7841 current_uiout
= saved_uiout
;
7847 print_stop_event (struct ui_out
*uiout
)
7849 struct cleanup
*old_chain
;
7850 struct target_waitstatus last
;
7852 struct thread_info
*tp
;
7854 get_last_target_status (&last_ptid
, &last
);
7856 old_chain
= make_cleanup (restore_current_uiout_cleanup
, current_uiout
);
7857 current_uiout
= uiout
;
7859 print_stop_location (&last
);
7861 /* Display the auto-display expressions. */
7864 do_cleanups (old_chain
);
7866 tp
= inferior_thread ();
7867 if (tp
->thread_fsm
!= NULL
7868 && thread_fsm_finished_p (tp
->thread_fsm
))
7870 struct return_value_info
*rv
;
7872 rv
= thread_fsm_return_value (tp
->thread_fsm
);
7874 print_return_value (uiout
, rv
);
7881 maybe_remove_breakpoints (void)
7883 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
7885 if (remove_breakpoints ())
7887 target_terminal_ours_for_output ();
7888 printf_filtered (_("Cannot remove breakpoints because "
7889 "program is no longer writable.\nFurther "
7890 "execution is probably impossible.\n"));
7895 /* The execution context that just caused a normal stop. */
7902 /* The event PTID. */
7906 /* If stopp for a thread event, this is the thread that caused the
7908 struct thread_info
*thread
;
7910 /* The inferior that caused the stop. */
7914 /* Returns a new stop context. If stopped for a thread event, this
7915 takes a strong reference to the thread. */
7917 static struct stop_context
*
7918 save_stop_context (void)
7920 struct stop_context
*sc
= XNEW (struct stop_context
);
7922 sc
->stop_id
= get_stop_id ();
7923 sc
->ptid
= inferior_ptid
;
7924 sc
->inf_num
= current_inferior ()->num
;
7926 if (!ptid_equal (inferior_ptid
, null_ptid
))
7928 /* Take a strong reference so that the thread can't be deleted
7930 sc
->thread
= inferior_thread ();
7931 sc
->thread
->refcount
++;
7939 /* Release a stop context previously created with save_stop_context.
7940 Releases the strong reference to the thread as well. */
7943 release_stop_context_cleanup (void *arg
)
7945 struct stop_context
*sc
= (struct stop_context
*) arg
;
7947 if (sc
->thread
!= NULL
)
7948 sc
->thread
->refcount
--;
7952 /* Return true if the current context no longer matches the saved stop
7956 stop_context_changed (struct stop_context
*prev
)
7958 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
7960 if (prev
->inf_num
!= current_inferior ()->num
)
7962 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
7964 if (get_stop_id () != prev
->stop_id
)
7974 struct target_waitstatus last
;
7976 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
7979 get_last_target_status (&last_ptid
, &last
);
7983 /* If an exception is thrown from this point on, make sure to
7984 propagate GDB's knowledge of the executing state to the
7985 frontend/user running state. A QUIT is an easy exception to see
7986 here, so do this before any filtered output. */
7988 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
7989 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
7990 || last
.kind
== TARGET_WAITKIND_EXITED
)
7992 /* On some targets, we may still have live threads in the
7993 inferior when we get a process exit event. E.g., for
7994 "checkpoint", when the current checkpoint/fork exits,
7995 linux-fork.c automatically switches to another fork from
7996 within target_mourn_inferior. */
7997 if (!ptid_equal (inferior_ptid
, null_ptid
))
7999 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8000 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8003 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8004 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8006 /* As we're presenting a stop, and potentially removing breakpoints,
8007 update the thread list so we can tell whether there are threads
8008 running on the target. With target remote, for example, we can
8009 only learn about new threads when we explicitly update the thread
8010 list. Do this before notifying the interpreters about signal
8011 stops, end of stepping ranges, etc., so that the "new thread"
8012 output is emitted before e.g., "Program received signal FOO",
8013 instead of after. */
8014 update_thread_list ();
8016 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8017 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
8019 /* As with the notification of thread events, we want to delay
8020 notifying the user that we've switched thread context until
8021 the inferior actually stops.
8023 There's no point in saying anything if the inferior has exited.
8024 Note that SIGNALLED here means "exited with a signal", not
8025 "received a signal".
8027 Also skip saying anything in non-stop mode. In that mode, as we
8028 don't want GDB to switch threads behind the user's back, to avoid
8029 races where the user is typing a command to apply to thread x,
8030 but GDB switches to thread y before the user finishes entering
8031 the command, fetch_inferior_event installs a cleanup to restore
8032 the current thread back to the thread the user had selected right
8033 after this event is handled, so we're not really switching, only
8034 informing of a stop. */
8036 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8037 && target_has_execution
8038 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8039 && last
.kind
!= TARGET_WAITKIND_EXITED
8040 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8042 target_terminal_ours_for_output ();
8043 printf_filtered (_("[Switching to %s]\n"),
8044 target_pid_to_str (inferior_ptid
));
8045 annotate_thread_changed ();
8046 previous_inferior_ptid
= inferior_ptid
;
8049 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8051 gdb_assert (sync_execution
|| !target_can_async_p ());
8053 target_terminal_ours_for_output ();
8054 printf_filtered (_("No unwaited-for children left.\n"));
8057 /* Note: this depends on the update_thread_list call above. */
8058 maybe_remove_breakpoints ();
8060 /* If an auto-display called a function and that got a signal,
8061 delete that auto-display to avoid an infinite recursion. */
8063 if (stopped_by_random_signal
)
8064 disable_current_display ();
8066 target_terminal_ours ();
8067 async_enable_stdin ();
8069 /* Let the user/frontend see the threads as stopped. */
8070 do_cleanups (old_chain
);
8072 /* Select innermost stack frame - i.e., current frame is frame 0,
8073 and current location is based on that. Handle the case where the
8074 dummy call is returning after being stopped. E.g. the dummy call
8075 previously hit a breakpoint. (If the dummy call returns
8076 normally, we won't reach here.) Do this before the stop hook is
8077 run, so that it doesn't get to see the temporary dummy frame,
8078 which is not where we'll present the stop. */
8079 if (has_stack_frames ())
8081 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8083 /* Pop the empty frame that contains the stack dummy. This
8084 also restores inferior state prior to the call (struct
8085 infcall_suspend_state). */
8086 struct frame_info
*frame
= get_current_frame ();
8088 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8090 /* frame_pop calls reinit_frame_cache as the last thing it
8091 does which means there's now no selected frame. */
8094 select_frame (get_current_frame ());
8096 /* Set the current source location. */
8097 set_current_sal_from_frame (get_current_frame ());
8100 /* Look up the hook_stop and run it (CLI internally handles problem
8101 of stop_command's pre-hook not existing). */
8102 if (stop_command
!= NULL
)
8104 struct stop_context
*saved_context
= save_stop_context ();
8105 struct cleanup
*old_chain
8106 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8108 catch_errors (hook_stop_stub
, stop_command
,
8109 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
8111 /* If the stop hook resumes the target, then there's no point in
8112 trying to notify about the previous stop; its context is
8113 gone. Likewise if the command switches thread or inferior --
8114 the observers would print a stop for the wrong
8116 if (stop_context_changed (saved_context
))
8118 do_cleanups (old_chain
);
8121 do_cleanups (old_chain
);
8124 /* Notify observers about the stop. This is where the interpreters
8125 print the stop event. */
8126 if (!ptid_equal (inferior_ptid
, null_ptid
))
8127 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
8130 observer_notify_normal_stop (NULL
, stop_print_frame
);
8132 annotate_stopped ();
8134 if (target_has_execution
)
8136 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8137 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8138 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8139 Delete any breakpoint that is to be deleted at the next stop. */
8140 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8143 /* Try to get rid of automatically added inferiors that are no
8144 longer needed. Keeping those around slows down things linearly.
8145 Note that this never removes the current inferior. */
8152 hook_stop_stub (void *cmd
)
8154 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
8159 signal_stop_state (int signo
)
8161 return signal_stop
[signo
];
8165 signal_print_state (int signo
)
8167 return signal_print
[signo
];
8171 signal_pass_state (int signo
)
8173 return signal_program
[signo
];
8177 signal_cache_update (int signo
)
8181 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8182 signal_cache_update (signo
);
8187 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8188 && signal_print
[signo
] == 0
8189 && signal_program
[signo
] == 1
8190 && signal_catch
[signo
] == 0);
8194 signal_stop_update (int signo
, int state
)
8196 int ret
= signal_stop
[signo
];
8198 signal_stop
[signo
] = state
;
8199 signal_cache_update (signo
);
8204 signal_print_update (int signo
, int state
)
8206 int ret
= signal_print
[signo
];
8208 signal_print
[signo
] = state
;
8209 signal_cache_update (signo
);
8214 signal_pass_update (int signo
, int state
)
8216 int ret
= signal_program
[signo
];
8218 signal_program
[signo
] = state
;
8219 signal_cache_update (signo
);
8223 /* Update the global 'signal_catch' from INFO and notify the
8227 signal_catch_update (const unsigned int *info
)
8231 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8232 signal_catch
[i
] = info
[i
] > 0;
8233 signal_cache_update (-1);
8234 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8238 sig_print_header (void)
8240 printf_filtered (_("Signal Stop\tPrint\tPass "
8241 "to program\tDescription\n"));
8245 sig_print_info (enum gdb_signal oursig
)
8247 const char *name
= gdb_signal_to_name (oursig
);
8248 int name_padding
= 13 - strlen (name
);
8250 if (name_padding
<= 0)
8253 printf_filtered ("%s", name
);
8254 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8255 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8256 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8257 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8258 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8261 /* Specify how various signals in the inferior should be handled. */
8264 handle_command (char *args
, int from_tty
)
8267 int digits
, wordlen
;
8268 int sigfirst
, signum
, siglast
;
8269 enum gdb_signal oursig
;
8272 unsigned char *sigs
;
8273 struct cleanup
*old_chain
;
8277 error_no_arg (_("signal to handle"));
8280 /* Allocate and zero an array of flags for which signals to handle. */
8282 nsigs
= (int) GDB_SIGNAL_LAST
;
8283 sigs
= (unsigned char *) alloca (nsigs
);
8284 memset (sigs
, 0, nsigs
);
8286 /* Break the command line up into args. */
8288 argv
= gdb_buildargv (args
);
8289 old_chain
= make_cleanup_freeargv (argv
);
8291 /* Walk through the args, looking for signal oursigs, signal names, and
8292 actions. Signal numbers and signal names may be interspersed with
8293 actions, with the actions being performed for all signals cumulatively
8294 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8296 while (*argv
!= NULL
)
8298 wordlen
= strlen (*argv
);
8299 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
8303 sigfirst
= siglast
= -1;
8305 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
8307 /* Apply action to all signals except those used by the
8308 debugger. Silently skip those. */
8311 siglast
= nsigs
- 1;
8313 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
8315 SET_SIGS (nsigs
, sigs
, signal_stop
);
8316 SET_SIGS (nsigs
, sigs
, signal_print
);
8318 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
8320 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8322 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
8324 SET_SIGS (nsigs
, sigs
, signal_print
);
8326 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
8328 SET_SIGS (nsigs
, sigs
, signal_program
);
8330 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
8332 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8334 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
8336 SET_SIGS (nsigs
, sigs
, signal_program
);
8338 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
8340 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8341 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8343 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
8345 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8347 else if (digits
> 0)
8349 /* It is numeric. The numeric signal refers to our own
8350 internal signal numbering from target.h, not to host/target
8351 signal number. This is a feature; users really should be
8352 using symbolic names anyway, and the common ones like
8353 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8355 sigfirst
= siglast
= (int)
8356 gdb_signal_from_command (atoi (*argv
));
8357 if ((*argv
)[digits
] == '-')
8360 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
8362 if (sigfirst
> siglast
)
8364 /* Bet he didn't figure we'd think of this case... */
8372 oursig
= gdb_signal_from_name (*argv
);
8373 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8375 sigfirst
= siglast
= (int) oursig
;
8379 /* Not a number and not a recognized flag word => complain. */
8380 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
8384 /* If any signal numbers or symbol names were found, set flags for
8385 which signals to apply actions to. */
8387 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8389 switch ((enum gdb_signal
) signum
)
8391 case GDB_SIGNAL_TRAP
:
8392 case GDB_SIGNAL_INT
:
8393 if (!allsigs
&& !sigs
[signum
])
8395 if (query (_("%s is used by the debugger.\n\
8396 Are you sure you want to change it? "),
8397 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8403 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8404 gdb_flush (gdb_stdout
);
8409 case GDB_SIGNAL_DEFAULT
:
8410 case GDB_SIGNAL_UNKNOWN
:
8411 /* Make sure that "all" doesn't print these. */
8422 for (signum
= 0; signum
< nsigs
; signum
++)
8425 signal_cache_update (-1);
8426 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8427 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8431 /* Show the results. */
8432 sig_print_header ();
8433 for (; signum
< nsigs
; signum
++)
8435 sig_print_info ((enum gdb_signal
) signum
);
8441 do_cleanups (old_chain
);
8444 /* Complete the "handle" command. */
8446 static VEC (char_ptr
) *
8447 handle_completer (struct cmd_list_element
*ignore
,
8448 const char *text
, const char *word
)
8450 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
8451 static const char * const keywords
[] =
8465 vec_signals
= signal_completer (ignore
, text
, word
);
8466 vec_keywords
= complete_on_enum (keywords
, word
, word
);
8468 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
8469 VEC_free (char_ptr
, vec_signals
);
8470 VEC_free (char_ptr
, vec_keywords
);
8475 gdb_signal_from_command (int num
)
8477 if (num
>= 1 && num
<= 15)
8478 return (enum gdb_signal
) num
;
8479 error (_("Only signals 1-15 are valid as numeric signals.\n\
8480 Use \"info signals\" for a list of symbolic signals."));
8483 /* Print current contents of the tables set by the handle command.
8484 It is possible we should just be printing signals actually used
8485 by the current target (but for things to work right when switching
8486 targets, all signals should be in the signal tables). */
8489 signals_info (char *signum_exp
, int from_tty
)
8491 enum gdb_signal oursig
;
8493 sig_print_header ();
8497 /* First see if this is a symbol name. */
8498 oursig
= gdb_signal_from_name (signum_exp
);
8499 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8501 /* No, try numeric. */
8503 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8505 sig_print_info (oursig
);
8509 printf_filtered ("\n");
8510 /* These ugly casts brought to you by the native VAX compiler. */
8511 for (oursig
= GDB_SIGNAL_FIRST
;
8512 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8513 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8517 if (oursig
!= GDB_SIGNAL_UNKNOWN
8518 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8519 sig_print_info (oursig
);
8522 printf_filtered (_("\nUse the \"handle\" command "
8523 "to change these tables.\n"));
8526 /* Check if it makes sense to read $_siginfo from the current thread
8527 at this point. If not, throw an error. */
8530 validate_siginfo_access (void)
8532 /* No current inferior, no siginfo. */
8533 if (ptid_equal (inferior_ptid
, null_ptid
))
8534 error (_("No thread selected."));
8536 /* Don't try to read from a dead thread. */
8537 if (is_exited (inferior_ptid
))
8538 error (_("The current thread has terminated"));
8540 /* ... or from a spinning thread. */
8541 if (is_running (inferior_ptid
))
8542 error (_("Selected thread is running."));
8545 /* The $_siginfo convenience variable is a bit special. We don't know
8546 for sure the type of the value until we actually have a chance to
8547 fetch the data. The type can change depending on gdbarch, so it is
8548 also dependent on which thread you have selected.
8550 1. making $_siginfo be an internalvar that creates a new value on
8553 2. making the value of $_siginfo be an lval_computed value. */
8555 /* This function implements the lval_computed support for reading a
8559 siginfo_value_read (struct value
*v
)
8561 LONGEST transferred
;
8563 validate_siginfo_access ();
8566 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8568 value_contents_all_raw (v
),
8570 TYPE_LENGTH (value_type (v
)));
8572 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8573 error (_("Unable to read siginfo"));
8576 /* This function implements the lval_computed support for writing a
8580 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8582 LONGEST transferred
;
8584 validate_siginfo_access ();
8586 transferred
= target_write (¤t_target
,
8587 TARGET_OBJECT_SIGNAL_INFO
,
8589 value_contents_all_raw (fromval
),
8591 TYPE_LENGTH (value_type (fromval
)));
8593 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8594 error (_("Unable to write siginfo"));
8597 static const struct lval_funcs siginfo_value_funcs
=
8603 /* Return a new value with the correct type for the siginfo object of
8604 the current thread using architecture GDBARCH. Return a void value
8605 if there's no object available. */
8607 static struct value
*
8608 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8611 if (target_has_stack
8612 && !ptid_equal (inferior_ptid
, null_ptid
)
8613 && gdbarch_get_siginfo_type_p (gdbarch
))
8615 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8617 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8620 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8624 /* infcall_suspend_state contains state about the program itself like its
8625 registers and any signal it received when it last stopped.
8626 This state must be restored regardless of how the inferior function call
8627 ends (either successfully, or after it hits a breakpoint or signal)
8628 if the program is to properly continue where it left off. */
8630 struct infcall_suspend_state
8632 struct thread_suspend_state thread_suspend
;
8636 struct regcache
*registers
;
8638 /* Format of SIGINFO_DATA or NULL if it is not present. */
8639 struct gdbarch
*siginfo_gdbarch
;
8641 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8642 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8643 content would be invalid. */
8644 gdb_byte
*siginfo_data
;
8647 struct infcall_suspend_state
*
8648 save_infcall_suspend_state (void)
8650 struct infcall_suspend_state
*inf_state
;
8651 struct thread_info
*tp
= inferior_thread ();
8652 struct regcache
*regcache
= get_current_regcache ();
8653 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8654 gdb_byte
*siginfo_data
= NULL
;
8656 if (gdbarch_get_siginfo_type_p (gdbarch
))
8658 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8659 size_t len
= TYPE_LENGTH (type
);
8660 struct cleanup
*back_to
;
8662 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8663 back_to
= make_cleanup (xfree
, siginfo_data
);
8665 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8666 siginfo_data
, 0, len
) == len
)
8667 discard_cleanups (back_to
);
8670 /* Errors ignored. */
8671 do_cleanups (back_to
);
8672 siginfo_data
= NULL
;
8676 inf_state
= XCNEW (struct infcall_suspend_state
);
8680 inf_state
->siginfo_gdbarch
= gdbarch
;
8681 inf_state
->siginfo_data
= siginfo_data
;
8684 inf_state
->thread_suspend
= tp
->suspend
;
8686 /* run_inferior_call will not use the signal due to its `proceed' call with
8687 GDB_SIGNAL_0 anyway. */
8688 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8690 inf_state
->stop_pc
= stop_pc
;
8692 inf_state
->registers
= regcache_dup (regcache
);
8697 /* Restore inferior session state to INF_STATE. */
8700 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8702 struct thread_info
*tp
= inferior_thread ();
8703 struct regcache
*regcache
= get_current_regcache ();
8704 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8706 tp
->suspend
= inf_state
->thread_suspend
;
8708 stop_pc
= inf_state
->stop_pc
;
8710 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8712 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8714 /* Errors ignored. */
8715 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8716 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8719 /* The inferior can be gone if the user types "print exit(0)"
8720 (and perhaps other times). */
8721 if (target_has_execution
)
8722 /* NB: The register write goes through to the target. */
8723 regcache_cpy (regcache
, inf_state
->registers
);
8725 discard_infcall_suspend_state (inf_state
);
8729 do_restore_infcall_suspend_state_cleanup (void *state
)
8731 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
8735 make_cleanup_restore_infcall_suspend_state
8736 (struct infcall_suspend_state
*inf_state
)
8738 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8742 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8744 regcache_xfree (inf_state
->registers
);
8745 xfree (inf_state
->siginfo_data
);
8750 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8752 return inf_state
->registers
;
8755 /* infcall_control_state contains state regarding gdb's control of the
8756 inferior itself like stepping control. It also contains session state like
8757 the user's currently selected frame. */
8759 struct infcall_control_state
8761 struct thread_control_state thread_control
;
8762 struct inferior_control_state inferior_control
;
8765 enum stop_stack_kind stop_stack_dummy
;
8766 int stopped_by_random_signal
;
8767 int stop_after_trap
;
8769 /* ID if the selected frame when the inferior function call was made. */
8770 struct frame_id selected_frame_id
;
8773 /* Save all of the information associated with the inferior<==>gdb
8776 struct infcall_control_state
*
8777 save_infcall_control_state (void)
8779 struct infcall_control_state
*inf_status
=
8780 XNEW (struct infcall_control_state
);
8781 struct thread_info
*tp
= inferior_thread ();
8782 struct inferior
*inf
= current_inferior ();
8784 inf_status
->thread_control
= tp
->control
;
8785 inf_status
->inferior_control
= inf
->control
;
8787 tp
->control
.step_resume_breakpoint
= NULL
;
8788 tp
->control
.exception_resume_breakpoint
= NULL
;
8790 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8791 chain. If caller's caller is walking the chain, they'll be happier if we
8792 hand them back the original chain when restore_infcall_control_state is
8794 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
8797 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
8798 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
8799 inf_status
->stop_after_trap
= stop_after_trap
;
8801 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
8807 restore_selected_frame (void *args
)
8809 struct frame_id
*fid
= (struct frame_id
*) args
;
8810 struct frame_info
*frame
;
8812 frame
= frame_find_by_id (*fid
);
8814 /* If inf_status->selected_frame_id is NULL, there was no previously
8818 warning (_("Unable to restore previously selected frame."));
8822 select_frame (frame
);
8827 /* Restore inferior session state to INF_STATUS. */
8830 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
8832 struct thread_info
*tp
= inferior_thread ();
8833 struct inferior
*inf
= current_inferior ();
8835 if (tp
->control
.step_resume_breakpoint
)
8836 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
8838 if (tp
->control
.exception_resume_breakpoint
)
8839 tp
->control
.exception_resume_breakpoint
->disposition
8840 = disp_del_at_next_stop
;
8842 /* Handle the bpstat_copy of the chain. */
8843 bpstat_clear (&tp
->control
.stop_bpstat
);
8845 tp
->control
= inf_status
->thread_control
;
8846 inf
->control
= inf_status
->inferior_control
;
8849 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
8850 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
8851 stop_after_trap
= inf_status
->stop_after_trap
;
8853 if (target_has_stack
)
8855 /* The point of catch_errors is that if the stack is clobbered,
8856 walking the stack might encounter a garbage pointer and
8857 error() trying to dereference it. */
8859 (restore_selected_frame
, &inf_status
->selected_frame_id
,
8860 "Unable to restore previously selected frame:\n",
8861 RETURN_MASK_ERROR
) == 0)
8862 /* Error in restoring the selected frame. Select the innermost
8864 select_frame (get_current_frame ());
8871 do_restore_infcall_control_state_cleanup (void *sts
)
8873 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
8877 make_cleanup_restore_infcall_control_state
8878 (struct infcall_control_state
*inf_status
)
8880 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
8884 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
8886 if (inf_status
->thread_control
.step_resume_breakpoint
)
8887 inf_status
->thread_control
.step_resume_breakpoint
->disposition
8888 = disp_del_at_next_stop
;
8890 if (inf_status
->thread_control
.exception_resume_breakpoint
)
8891 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
8892 = disp_del_at_next_stop
;
8894 /* See save_infcall_control_state for info on stop_bpstat. */
8895 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
8900 /* restore_inferior_ptid() will be used by the cleanup machinery
8901 to restore the inferior_ptid value saved in a call to
8902 save_inferior_ptid(). */
8905 restore_inferior_ptid (void *arg
)
8907 ptid_t
*saved_ptid_ptr
= (ptid_t
*) arg
;
8909 inferior_ptid
= *saved_ptid_ptr
;
8913 /* Save the value of inferior_ptid so that it may be restored by a
8914 later call to do_cleanups(). Returns the struct cleanup pointer
8915 needed for later doing the cleanup. */
8918 save_inferior_ptid (void)
8920 ptid_t
*saved_ptid_ptr
= XNEW (ptid_t
);
8922 *saved_ptid_ptr
= inferior_ptid
;
8923 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
8929 clear_exit_convenience_vars (void)
8931 clear_internalvar (lookup_internalvar ("_exitsignal"));
8932 clear_internalvar (lookup_internalvar ("_exitcode"));
8936 /* User interface for reverse debugging:
8937 Set exec-direction / show exec-direction commands
8938 (returns error unless target implements to_set_exec_direction method). */
8940 int execution_direction
= EXEC_FORWARD
;
8941 static const char exec_forward
[] = "forward";
8942 static const char exec_reverse
[] = "reverse";
8943 static const char *exec_direction
= exec_forward
;
8944 static const char *const exec_direction_names
[] = {
8951 set_exec_direction_func (char *args
, int from_tty
,
8952 struct cmd_list_element
*cmd
)
8954 if (target_can_execute_reverse
)
8956 if (!strcmp (exec_direction
, exec_forward
))
8957 execution_direction
= EXEC_FORWARD
;
8958 else if (!strcmp (exec_direction
, exec_reverse
))
8959 execution_direction
= EXEC_REVERSE
;
8963 exec_direction
= exec_forward
;
8964 error (_("Target does not support this operation."));
8969 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
8970 struct cmd_list_element
*cmd
, const char *value
)
8972 switch (execution_direction
) {
8974 fprintf_filtered (out
, _("Forward.\n"));
8977 fprintf_filtered (out
, _("Reverse.\n"));
8980 internal_error (__FILE__
, __LINE__
,
8981 _("bogus execution_direction value: %d"),
8982 (int) execution_direction
);
8987 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
8988 struct cmd_list_element
*c
, const char *value
)
8990 fprintf_filtered (file
, _("Resuming the execution of threads "
8991 "of all processes is %s.\n"), value
);
8994 /* Implementation of `siginfo' variable. */
8996 static const struct internalvar_funcs siginfo_funcs
=
9003 /* Callback for infrun's target events source. This is marked when a
9004 thread has a pending status to process. */
9007 infrun_async_inferior_event_handler (gdb_client_data data
)
9009 inferior_event_handler (INF_REG_EVENT
, NULL
);
9013 _initialize_infrun (void)
9017 struct cmd_list_element
*c
;
9019 /* Register extra event sources in the event loop. */
9020 infrun_async_inferior_event_token
9021 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9023 add_info ("signals", signals_info
, _("\
9024 What debugger does when program gets various signals.\n\
9025 Specify a signal as argument to print info on that signal only."));
9026 add_info_alias ("handle", "signals", 0);
9028 c
= add_com ("handle", class_run
, handle_command
, _("\
9029 Specify how to handle signals.\n\
9030 Usage: handle SIGNAL [ACTIONS]\n\
9031 Args are signals and actions to apply to those signals.\n\
9032 If no actions are specified, the current settings for the specified signals\n\
9033 will be displayed instead.\n\
9035 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9036 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9037 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9038 The special arg \"all\" is recognized to mean all signals except those\n\
9039 used by the debugger, typically SIGTRAP and SIGINT.\n\
9041 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9042 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9043 Stop means reenter debugger if this signal happens (implies print).\n\
9044 Print means print a message if this signal happens.\n\
9045 Pass means let program see this signal; otherwise program doesn't know.\n\
9046 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9047 Pass and Stop may be combined.\n\
9049 Multiple signals may be specified. Signal numbers and signal names\n\
9050 may be interspersed with actions, with the actions being performed for\n\
9051 all signals cumulatively specified."));
9052 set_cmd_completer (c
, handle_completer
);
9055 stop_command
= add_cmd ("stop", class_obscure
,
9056 not_just_help_class_command
, _("\
9057 There is no `stop' command, but you can set a hook on `stop'.\n\
9058 This allows you to set a list of commands to be run each time execution\n\
9059 of the program stops."), &cmdlist
);
9061 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9062 Set inferior debugging."), _("\
9063 Show inferior debugging."), _("\
9064 When non-zero, inferior specific debugging is enabled."),
9067 &setdebuglist
, &showdebuglist
);
9069 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9070 &debug_displaced
, _("\
9071 Set displaced stepping debugging."), _("\
9072 Show displaced stepping debugging."), _("\
9073 When non-zero, displaced stepping specific debugging is enabled."),
9075 show_debug_displaced
,
9076 &setdebuglist
, &showdebuglist
);
9078 add_setshow_boolean_cmd ("non-stop", no_class
,
9080 Set whether gdb controls the inferior in non-stop mode."), _("\
9081 Show whether gdb controls the inferior in non-stop mode."), _("\
9082 When debugging a multi-threaded program and this setting is\n\
9083 off (the default, also called all-stop mode), when one thread stops\n\
9084 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9085 all other threads in the program while you interact with the thread of\n\
9086 interest. When you continue or step a thread, you can allow the other\n\
9087 threads to run, or have them remain stopped, but while you inspect any\n\
9088 thread's state, all threads stop.\n\
9090 In non-stop mode, when one thread stops, other threads can continue\n\
9091 to run freely. You'll be able to step each thread independently,\n\
9092 leave it stopped or free to run as needed."),
9098 numsigs
= (int) GDB_SIGNAL_LAST
;
9099 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9100 signal_print
= XNEWVEC (unsigned char, numsigs
);
9101 signal_program
= XNEWVEC (unsigned char, numsigs
);
9102 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9103 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9104 for (i
= 0; i
< numsigs
; i
++)
9107 signal_print
[i
] = 1;
9108 signal_program
[i
] = 1;
9109 signal_catch
[i
] = 0;
9112 /* Signals caused by debugger's own actions should not be given to
9113 the program afterwards.
9115 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9116 explicitly specifies that it should be delivered to the target
9117 program. Typically, that would occur when a user is debugging a
9118 target monitor on a simulator: the target monitor sets a
9119 breakpoint; the simulator encounters this breakpoint and halts
9120 the simulation handing control to GDB; GDB, noting that the stop
9121 address doesn't map to any known breakpoint, returns control back
9122 to the simulator; the simulator then delivers the hardware
9123 equivalent of a GDB_SIGNAL_TRAP to the program being
9125 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9126 signal_program
[GDB_SIGNAL_INT
] = 0;
9128 /* Signals that are not errors should not normally enter the debugger. */
9129 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9130 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9131 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9132 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9133 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9134 signal_print
[GDB_SIGNAL_PROF
] = 0;
9135 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9136 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9137 signal_stop
[GDB_SIGNAL_IO
] = 0;
9138 signal_print
[GDB_SIGNAL_IO
] = 0;
9139 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9140 signal_print
[GDB_SIGNAL_POLL
] = 0;
9141 signal_stop
[GDB_SIGNAL_URG
] = 0;
9142 signal_print
[GDB_SIGNAL_URG
] = 0;
9143 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9144 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9145 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9146 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9148 /* These signals are used internally by user-level thread
9149 implementations. (See signal(5) on Solaris.) Like the above
9150 signals, a healthy program receives and handles them as part of
9151 its normal operation. */
9152 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9153 signal_print
[GDB_SIGNAL_LWP
] = 0;
9154 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9155 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9156 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9157 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9159 /* Update cached state. */
9160 signal_cache_update (-1);
9162 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9163 &stop_on_solib_events
, _("\
9164 Set stopping for shared library events."), _("\
9165 Show stopping for shared library events."), _("\
9166 If nonzero, gdb will give control to the user when the dynamic linker\n\
9167 notifies gdb of shared library events. The most common event of interest\n\
9168 to the user would be loading/unloading of a new library."),
9169 set_stop_on_solib_events
,
9170 show_stop_on_solib_events
,
9171 &setlist
, &showlist
);
9173 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9174 follow_fork_mode_kind_names
,
9175 &follow_fork_mode_string
, _("\
9176 Set debugger response to a program call of fork or vfork."), _("\
9177 Show debugger response to a program call of fork or vfork."), _("\
9178 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9179 parent - the original process is debugged after a fork\n\
9180 child - the new process is debugged after a fork\n\
9181 The unfollowed process will continue to run.\n\
9182 By default, the debugger will follow the parent process."),
9184 show_follow_fork_mode_string
,
9185 &setlist
, &showlist
);
9187 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9188 follow_exec_mode_names
,
9189 &follow_exec_mode_string
, _("\
9190 Set debugger response to a program call of exec."), _("\
9191 Show debugger response to a program call of exec."), _("\
9192 An exec call replaces the program image of a process.\n\
9194 follow-exec-mode can be:\n\
9196 new - the debugger creates a new inferior and rebinds the process\n\
9197 to this new inferior. The program the process was running before\n\
9198 the exec call can be restarted afterwards by restarting the original\n\
9201 same - the debugger keeps the process bound to the same inferior.\n\
9202 The new executable image replaces the previous executable loaded in\n\
9203 the inferior. Restarting the inferior after the exec call restarts\n\
9204 the executable the process was running after the exec call.\n\
9206 By default, the debugger will use the same inferior."),
9208 show_follow_exec_mode_string
,
9209 &setlist
, &showlist
);
9211 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9212 scheduler_enums
, &scheduler_mode
, _("\
9213 Set mode for locking scheduler during execution."), _("\
9214 Show mode for locking scheduler during execution."), _("\
9215 off == no locking (threads may preempt at any time)\n\
9216 on == full locking (no thread except the current thread may run)\n\
9217 This applies to both normal execution and replay mode.\n\
9218 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9219 In this mode, other threads may run during other commands.\n\
9220 This applies to both normal execution and replay mode.\n\
9221 replay == scheduler locked in replay mode and unlocked during normal execution."),
9222 set_schedlock_func
, /* traps on target vector */
9223 show_scheduler_mode
,
9224 &setlist
, &showlist
);
9226 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9227 Set mode for resuming threads of all processes."), _("\
9228 Show mode for resuming threads of all processes."), _("\
9229 When on, execution commands (such as 'continue' or 'next') resume all\n\
9230 threads of all processes. When off (which is the default), execution\n\
9231 commands only resume the threads of the current process. The set of\n\
9232 threads that are resumed is further refined by the scheduler-locking\n\
9233 mode (see help set scheduler-locking)."),
9235 show_schedule_multiple
,
9236 &setlist
, &showlist
);
9238 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9239 Set mode of the step operation."), _("\
9240 Show mode of the step operation."), _("\
9241 When set, doing a step over a function without debug line information\n\
9242 will stop at the first instruction of that function. Otherwise, the\n\
9243 function is skipped and the step command stops at a different source line."),
9245 show_step_stop_if_no_debug
,
9246 &setlist
, &showlist
);
9248 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9249 &can_use_displaced_stepping
, _("\
9250 Set debugger's willingness to use displaced stepping."), _("\
9251 Show debugger's willingness to use displaced stepping."), _("\
9252 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9253 supported by the target architecture. If off, gdb will not use displaced\n\
9254 stepping to step over breakpoints, even if such is supported by the target\n\
9255 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9256 if the target architecture supports it and non-stop mode is active, but will not\n\
9257 use it in all-stop mode (see help set non-stop)."),
9259 show_can_use_displaced_stepping
,
9260 &setlist
, &showlist
);
9262 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9263 &exec_direction
, _("Set direction of execution.\n\
9264 Options are 'forward' or 'reverse'."),
9265 _("Show direction of execution (forward/reverse)."),
9266 _("Tells gdb whether to execute forward or backward."),
9267 set_exec_direction_func
, show_exec_direction_func
,
9268 &setlist
, &showlist
);
9270 /* Set/show detach-on-fork: user-settable mode. */
9272 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9273 Set whether gdb will detach the child of a fork."), _("\
9274 Show whether gdb will detach the child of a fork."), _("\
9275 Tells gdb whether to detach the child of a fork."),
9276 NULL
, NULL
, &setlist
, &showlist
);
9278 /* Set/show disable address space randomization mode. */
9280 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9281 &disable_randomization
, _("\
9282 Set disabling of debuggee's virtual address space randomization."), _("\
9283 Show disabling of debuggee's virtual address space randomization."), _("\
9284 When this mode is on (which is the default), randomization of the virtual\n\
9285 address space is disabled. Standalone programs run with the randomization\n\
9286 enabled by default on some platforms."),
9287 &set_disable_randomization
,
9288 &show_disable_randomization
,
9289 &setlist
, &showlist
);
9291 /* ptid initializations */
9292 inferior_ptid
= null_ptid
;
9293 target_last_wait_ptid
= minus_one_ptid
;
9295 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9296 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9297 observer_attach_thread_exit (infrun_thread_thread_exit
);
9298 observer_attach_inferior_exit (infrun_inferior_exit
);
9300 /* Explicitly create without lookup, since that tries to create a
9301 value with a void typed value, and when we get here, gdbarch
9302 isn't initialized yet. At this point, we're quite sure there
9303 isn't another convenience variable of the same name. */
9304 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9306 add_setshow_boolean_cmd ("observer", no_class
,
9307 &observer_mode_1
, _("\
9308 Set whether gdb controls the inferior in observer mode."), _("\
9309 Show whether gdb controls the inferior in observer mode."), _("\
9310 In observer mode, GDB can get data from the inferior, but not\n\
9311 affect its execution. Registers and memory may not be changed,\n\
9312 breakpoints may not be set, and the program cannot be interrupted\n\