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 after stop if current stack frame should be printed. */
392 static int stop_print_frame
;
394 /* This is a cached copy of the pid/waitstatus of the last event
395 returned by target_wait()/deprecated_target_wait_hook(). This
396 information is returned by get_last_target_status(). */
397 static ptid_t target_last_wait_ptid
;
398 static struct target_waitstatus target_last_waitstatus
;
400 static void context_switch (ptid_t ptid
);
402 void init_thread_stepping_state (struct thread_info
*tss
);
404 static const char follow_fork_mode_child
[] = "child";
405 static const char follow_fork_mode_parent
[] = "parent";
407 static const char *const follow_fork_mode_kind_names
[] = {
408 follow_fork_mode_child
,
409 follow_fork_mode_parent
,
413 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
415 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
416 struct cmd_list_element
*c
, const char *value
)
418 fprintf_filtered (file
,
419 _("Debugger response to a program "
420 "call of fork or vfork is \"%s\".\n"),
425 /* Handle changes to the inferior list based on the type of fork,
426 which process is being followed, and whether the other process
427 should be detached. On entry inferior_ptid must be the ptid of
428 the fork parent. At return inferior_ptid is the ptid of the
429 followed inferior. */
432 follow_fork_inferior (int follow_child
, int detach_fork
)
435 ptid_t parent_ptid
, child_ptid
;
437 has_vforked
= (inferior_thread ()->pending_follow
.kind
438 == TARGET_WAITKIND_VFORKED
);
439 parent_ptid
= inferior_ptid
;
440 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
443 && !non_stop
/* Non-stop always resumes both branches. */
444 && (!target_is_async_p () || sync_execution
)
445 && !(follow_child
|| detach_fork
|| sched_multi
))
447 /* The parent stays blocked inside the vfork syscall until the
448 child execs or exits. If we don't let the child run, then
449 the parent stays blocked. If we're telling the parent to run
450 in the foreground, the user will not be able to ctrl-c to get
451 back the terminal, effectively hanging the debug session. */
452 fprintf_filtered (gdb_stderr
, _("\
453 Can not resume the parent process over vfork in the foreground while\n\
454 holding the child stopped. Try \"set detach-on-fork\" or \
455 \"set schedule-multiple\".\n"));
456 /* FIXME output string > 80 columns. */
462 /* Detach new forked process? */
465 struct cleanup
*old_chain
;
467 /* Before detaching from the child, remove all breakpoints
468 from it. If we forked, then this has already been taken
469 care of by infrun.c. If we vforked however, any
470 breakpoint inserted in the parent is visible in the
471 child, even those added while stopped in a vfork
472 catchpoint. This will remove the breakpoints from the
473 parent also, but they'll be reinserted below. */
476 /* Keep breakpoints list in sync. */
477 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
480 if (info_verbose
|| debug_infrun
)
482 /* Ensure that we have a process ptid. */
483 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
485 target_terminal_ours_for_output ();
486 fprintf_filtered (gdb_stdlog
,
487 _("Detaching after %s from child %s.\n"),
488 has_vforked
? "vfork" : "fork",
489 target_pid_to_str (process_ptid
));
494 struct inferior
*parent_inf
, *child_inf
;
495 struct cleanup
*old_chain
;
497 /* Add process to GDB's tables. */
498 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
500 parent_inf
= current_inferior ();
501 child_inf
->attach_flag
= parent_inf
->attach_flag
;
502 copy_terminal_info (child_inf
, parent_inf
);
503 child_inf
->gdbarch
= parent_inf
->gdbarch
;
504 copy_inferior_target_desc_info (child_inf
, parent_inf
);
506 old_chain
= save_inferior_ptid ();
507 save_current_program_space ();
509 inferior_ptid
= child_ptid
;
510 add_thread (inferior_ptid
);
511 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
513 /* If this is a vfork child, then the address-space is
514 shared with the parent. */
517 child_inf
->pspace
= parent_inf
->pspace
;
518 child_inf
->aspace
= parent_inf
->aspace
;
520 /* The parent will be frozen until the child is done
521 with the shared region. Keep track of the
523 child_inf
->vfork_parent
= parent_inf
;
524 child_inf
->pending_detach
= 0;
525 parent_inf
->vfork_child
= child_inf
;
526 parent_inf
->pending_detach
= 0;
530 child_inf
->aspace
= new_address_space ();
531 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
532 child_inf
->removable
= 1;
533 set_current_program_space (child_inf
->pspace
);
534 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
536 /* Let the shared library layer (e.g., solib-svr4) learn
537 about this new process, relocate the cloned exec, pull
538 in shared libraries, and install the solib event
539 breakpoint. If a "cloned-VM" event was propagated
540 better throughout the core, this wouldn't be
542 solib_create_inferior_hook (0);
545 do_cleanups (old_chain
);
550 struct inferior
*parent_inf
;
552 parent_inf
= current_inferior ();
554 /* If we detached from the child, then we have to be careful
555 to not insert breakpoints in the parent until the child
556 is done with the shared memory region. However, if we're
557 staying attached to the child, then we can and should
558 insert breakpoints, so that we can debug it. A
559 subsequent child exec or exit is enough to know when does
560 the child stops using the parent's address space. */
561 parent_inf
->waiting_for_vfork_done
= detach_fork
;
562 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
567 /* Follow the child. */
568 struct inferior
*parent_inf
, *child_inf
;
569 struct program_space
*parent_pspace
;
571 if (info_verbose
|| debug_infrun
)
573 target_terminal_ours_for_output ();
574 fprintf_filtered (gdb_stdlog
,
575 _("Attaching after %s %s to child %s.\n"),
576 target_pid_to_str (parent_ptid
),
577 has_vforked
? "vfork" : "fork",
578 target_pid_to_str (child_ptid
));
581 /* Add the new inferior first, so that the target_detach below
582 doesn't unpush the target. */
584 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
586 parent_inf
= current_inferior ();
587 child_inf
->attach_flag
= parent_inf
->attach_flag
;
588 copy_terminal_info (child_inf
, parent_inf
);
589 child_inf
->gdbarch
= parent_inf
->gdbarch
;
590 copy_inferior_target_desc_info (child_inf
, parent_inf
);
592 parent_pspace
= parent_inf
->pspace
;
594 /* If we're vforking, we want to hold on to the parent until the
595 child exits or execs. At child exec or exit time we can
596 remove the old breakpoints from the parent and detach or
597 resume debugging it. Otherwise, detach the parent now; we'll
598 want to reuse it's program/address spaces, but we can't set
599 them to the child before removing breakpoints from the
600 parent, otherwise, the breakpoints module could decide to
601 remove breakpoints from the wrong process (since they'd be
602 assigned to the same address space). */
606 gdb_assert (child_inf
->vfork_parent
== NULL
);
607 gdb_assert (parent_inf
->vfork_child
== NULL
);
608 child_inf
->vfork_parent
= parent_inf
;
609 child_inf
->pending_detach
= 0;
610 parent_inf
->vfork_child
= child_inf
;
611 parent_inf
->pending_detach
= detach_fork
;
612 parent_inf
->waiting_for_vfork_done
= 0;
614 else if (detach_fork
)
616 if (info_verbose
|| debug_infrun
)
618 /* Ensure that we have a process ptid. */
619 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
621 target_terminal_ours_for_output ();
622 fprintf_filtered (gdb_stdlog
,
623 _("Detaching after fork from "
625 target_pid_to_str (process_ptid
));
628 target_detach (NULL
, 0);
631 /* Note that the detach above makes PARENT_INF dangling. */
633 /* Add the child thread to the appropriate lists, and switch to
634 this new thread, before cloning the program space, and
635 informing the solib layer about this new process. */
637 inferior_ptid
= child_ptid
;
638 add_thread (inferior_ptid
);
640 /* If this is a vfork child, then the address-space is shared
641 with the parent. If we detached from the parent, then we can
642 reuse the parent's program/address spaces. */
643 if (has_vforked
|| detach_fork
)
645 child_inf
->pspace
= parent_pspace
;
646 child_inf
->aspace
= child_inf
->pspace
->aspace
;
650 child_inf
->aspace
= new_address_space ();
651 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
652 child_inf
->removable
= 1;
653 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
654 set_current_program_space (child_inf
->pspace
);
655 clone_program_space (child_inf
->pspace
, parent_pspace
);
657 /* Let the shared library layer (e.g., solib-svr4) learn
658 about this new process, relocate the cloned exec, pull in
659 shared libraries, and install the solib event breakpoint.
660 If a "cloned-VM" event was propagated better throughout
661 the core, this wouldn't be required. */
662 solib_create_inferior_hook (0);
666 return target_follow_fork (follow_child
, detach_fork
);
669 /* Tell the target to follow the fork we're stopped at. Returns true
670 if the inferior should be resumed; false, if the target for some
671 reason decided it's best not to resume. */
676 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
677 int should_resume
= 1;
678 struct thread_info
*tp
;
680 /* Copy user stepping state to the new inferior thread. FIXME: the
681 followed fork child thread should have a copy of most of the
682 parent thread structure's run control related fields, not just these.
683 Initialized to avoid "may be used uninitialized" warnings from gcc. */
684 struct breakpoint
*step_resume_breakpoint
= NULL
;
685 struct breakpoint
*exception_resume_breakpoint
= NULL
;
686 CORE_ADDR step_range_start
= 0;
687 CORE_ADDR step_range_end
= 0;
688 struct frame_id step_frame_id
= { 0 };
689 struct interp
*command_interp
= NULL
;
694 struct target_waitstatus wait_status
;
696 /* Get the last target status returned by target_wait(). */
697 get_last_target_status (&wait_ptid
, &wait_status
);
699 /* If not stopped at a fork event, then there's nothing else to
701 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
702 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
705 /* Check if we switched over from WAIT_PTID, since the event was
707 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
708 && !ptid_equal (inferior_ptid
, wait_ptid
))
710 /* We did. Switch back to WAIT_PTID thread, to tell the
711 target to follow it (in either direction). We'll
712 afterwards refuse to resume, and inform the user what
714 switch_to_thread (wait_ptid
);
719 tp
= inferior_thread ();
721 /* If there were any forks/vforks that were caught and are now to be
722 followed, then do so now. */
723 switch (tp
->pending_follow
.kind
)
725 case TARGET_WAITKIND_FORKED
:
726 case TARGET_WAITKIND_VFORKED
:
728 ptid_t parent
, child
;
730 /* If the user did a next/step, etc, over a fork call,
731 preserve the stepping state in the fork child. */
732 if (follow_child
&& should_resume
)
734 step_resume_breakpoint
= clone_momentary_breakpoint
735 (tp
->control
.step_resume_breakpoint
);
736 step_range_start
= tp
->control
.step_range_start
;
737 step_range_end
= tp
->control
.step_range_end
;
738 step_frame_id
= tp
->control
.step_frame_id
;
739 exception_resume_breakpoint
740 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
741 command_interp
= tp
->control
.command_interp
;
743 /* For now, delete the parent's sr breakpoint, otherwise,
744 parent/child sr breakpoints are considered duplicates,
745 and the child version will not be installed. Remove
746 this when the breakpoints module becomes aware of
747 inferiors and address spaces. */
748 delete_step_resume_breakpoint (tp
);
749 tp
->control
.step_range_start
= 0;
750 tp
->control
.step_range_end
= 0;
751 tp
->control
.step_frame_id
= null_frame_id
;
752 delete_exception_resume_breakpoint (tp
);
753 tp
->control
.command_interp
= NULL
;
756 parent
= inferior_ptid
;
757 child
= tp
->pending_follow
.value
.related_pid
;
759 /* Set up inferior(s) as specified by the caller, and tell the
760 target to do whatever is necessary to follow either parent
762 if (follow_fork_inferior (follow_child
, detach_fork
))
764 /* Target refused to follow, or there's some other reason
765 we shouldn't resume. */
770 /* This pending follow fork event is now handled, one way
771 or another. The previous selected thread may be gone
772 from the lists by now, but if it is still around, need
773 to clear the pending follow request. */
774 tp
= find_thread_ptid (parent
);
776 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
778 /* This makes sure we don't try to apply the "Switched
779 over from WAIT_PID" logic above. */
780 nullify_last_target_wait_ptid ();
782 /* If we followed the child, switch to it... */
785 switch_to_thread (child
);
787 /* ... and preserve the stepping state, in case the
788 user was stepping over the fork call. */
791 tp
= inferior_thread ();
792 tp
->control
.step_resume_breakpoint
793 = step_resume_breakpoint
;
794 tp
->control
.step_range_start
= step_range_start
;
795 tp
->control
.step_range_end
= step_range_end
;
796 tp
->control
.step_frame_id
= step_frame_id
;
797 tp
->control
.exception_resume_breakpoint
798 = exception_resume_breakpoint
;
799 tp
->control
.command_interp
= command_interp
;
803 /* If we get here, it was because we're trying to
804 resume from a fork catchpoint, but, the user
805 has switched threads away from the thread that
806 forked. In that case, the resume command
807 issued is most likely not applicable to the
808 child, so just warn, and refuse to resume. */
809 warning (_("Not resuming: switched threads "
810 "before following fork child."));
813 /* Reset breakpoints in the child as appropriate. */
814 follow_inferior_reset_breakpoints ();
817 switch_to_thread (parent
);
821 case TARGET_WAITKIND_SPURIOUS
:
822 /* Nothing to follow. */
825 internal_error (__FILE__
, __LINE__
,
826 "Unexpected pending_follow.kind %d\n",
827 tp
->pending_follow
.kind
);
831 return should_resume
;
835 follow_inferior_reset_breakpoints (void)
837 struct thread_info
*tp
= inferior_thread ();
839 /* Was there a step_resume breakpoint? (There was if the user
840 did a "next" at the fork() call.) If so, explicitly reset its
841 thread number. Cloned step_resume breakpoints are disabled on
842 creation, so enable it here now that it is associated with the
845 step_resumes are a form of bp that are made to be per-thread.
846 Since we created the step_resume bp when the parent process
847 was being debugged, and now are switching to the child process,
848 from the breakpoint package's viewpoint, that's a switch of
849 "threads". We must update the bp's notion of which thread
850 it is for, or it'll be ignored when it triggers. */
852 if (tp
->control
.step_resume_breakpoint
)
854 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
855 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
858 /* Treat exception_resume breakpoints like step_resume breakpoints. */
859 if (tp
->control
.exception_resume_breakpoint
)
861 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
862 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
865 /* Reinsert all breakpoints in the child. The user may have set
866 breakpoints after catching the fork, in which case those
867 were never set in the child, but only in the parent. This makes
868 sure the inserted breakpoints match the breakpoint list. */
870 breakpoint_re_set ();
871 insert_breakpoints ();
874 /* The child has exited or execed: resume threads of the parent the
875 user wanted to be executing. */
878 proceed_after_vfork_done (struct thread_info
*thread
,
881 int pid
= * (int *) arg
;
883 if (ptid_get_pid (thread
->ptid
) == pid
884 && is_running (thread
->ptid
)
885 && !is_executing (thread
->ptid
)
886 && !thread
->stop_requested
887 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
890 fprintf_unfiltered (gdb_stdlog
,
891 "infrun: resuming vfork parent thread %s\n",
892 target_pid_to_str (thread
->ptid
));
894 switch_to_thread (thread
->ptid
);
895 clear_proceed_status (0);
896 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
902 /* Called whenever we notice an exec or exit event, to handle
903 detaching or resuming a vfork parent. */
906 handle_vfork_child_exec_or_exit (int exec
)
908 struct inferior
*inf
= current_inferior ();
910 if (inf
->vfork_parent
)
912 int resume_parent
= -1;
914 /* This exec or exit marks the end of the shared memory region
915 between the parent and the child. If the user wanted to
916 detach from the parent, now is the time. */
918 if (inf
->vfork_parent
->pending_detach
)
920 struct thread_info
*tp
;
921 struct cleanup
*old_chain
;
922 struct program_space
*pspace
;
923 struct address_space
*aspace
;
925 /* follow-fork child, detach-on-fork on. */
927 inf
->vfork_parent
->pending_detach
= 0;
931 /* If we're handling a child exit, then inferior_ptid
932 points at the inferior's pid, not to a thread. */
933 old_chain
= save_inferior_ptid ();
934 save_current_program_space ();
935 save_current_inferior ();
938 old_chain
= save_current_space_and_thread ();
940 /* We're letting loose of the parent. */
941 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
942 switch_to_thread (tp
->ptid
);
944 /* We're about to detach from the parent, which implicitly
945 removes breakpoints from its address space. There's a
946 catch here: we want to reuse the spaces for the child,
947 but, parent/child are still sharing the pspace at this
948 point, although the exec in reality makes the kernel give
949 the child a fresh set of new pages. The problem here is
950 that the breakpoints module being unaware of this, would
951 likely chose the child process to write to the parent
952 address space. Swapping the child temporarily away from
953 the spaces has the desired effect. Yes, this is "sort
956 pspace
= inf
->pspace
;
957 aspace
= inf
->aspace
;
961 if (debug_infrun
|| info_verbose
)
963 target_terminal_ours_for_output ();
967 fprintf_filtered (gdb_stdlog
,
968 _("Detaching vfork parent process "
969 "%d after child exec.\n"),
970 inf
->vfork_parent
->pid
);
974 fprintf_filtered (gdb_stdlog
,
975 _("Detaching vfork parent process "
976 "%d after child exit.\n"),
977 inf
->vfork_parent
->pid
);
981 target_detach (NULL
, 0);
984 inf
->pspace
= pspace
;
985 inf
->aspace
= aspace
;
987 do_cleanups (old_chain
);
991 /* We're staying attached to the parent, so, really give the
992 child a new address space. */
993 inf
->pspace
= add_program_space (maybe_new_address_space ());
994 inf
->aspace
= inf
->pspace
->aspace
;
996 set_current_program_space (inf
->pspace
);
998 resume_parent
= inf
->vfork_parent
->pid
;
1000 /* Break the bonds. */
1001 inf
->vfork_parent
->vfork_child
= NULL
;
1005 struct cleanup
*old_chain
;
1006 struct program_space
*pspace
;
1008 /* If this is a vfork child exiting, then the pspace and
1009 aspaces were shared with the parent. Since we're
1010 reporting the process exit, we'll be mourning all that is
1011 found in the address space, and switching to null_ptid,
1012 preparing to start a new inferior. But, since we don't
1013 want to clobber the parent's address/program spaces, we
1014 go ahead and create a new one for this exiting
1017 /* Switch to null_ptid, so that clone_program_space doesn't want
1018 to read the selected frame of a dead process. */
1019 old_chain
= save_inferior_ptid ();
1020 inferior_ptid
= null_ptid
;
1022 /* This inferior is dead, so avoid giving the breakpoints
1023 module the option to write through to it (cloning a
1024 program space resets breakpoints). */
1027 pspace
= add_program_space (maybe_new_address_space ());
1028 set_current_program_space (pspace
);
1030 inf
->symfile_flags
= SYMFILE_NO_READ
;
1031 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1032 inf
->pspace
= pspace
;
1033 inf
->aspace
= pspace
->aspace
;
1035 /* Put back inferior_ptid. We'll continue mourning this
1037 do_cleanups (old_chain
);
1039 resume_parent
= inf
->vfork_parent
->pid
;
1040 /* Break the bonds. */
1041 inf
->vfork_parent
->vfork_child
= NULL
;
1044 inf
->vfork_parent
= NULL
;
1046 gdb_assert (current_program_space
== inf
->pspace
);
1048 if (non_stop
&& resume_parent
!= -1)
1050 /* If the user wanted the parent to be running, let it go
1052 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1055 fprintf_unfiltered (gdb_stdlog
,
1056 "infrun: resuming vfork parent process %d\n",
1059 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1061 do_cleanups (old_chain
);
1066 /* Enum strings for "set|show follow-exec-mode". */
1068 static const char follow_exec_mode_new
[] = "new";
1069 static const char follow_exec_mode_same
[] = "same";
1070 static const char *const follow_exec_mode_names
[] =
1072 follow_exec_mode_new
,
1073 follow_exec_mode_same
,
1077 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1079 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1080 struct cmd_list_element
*c
, const char *value
)
1082 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1085 /* EXECD_PATHNAME is assumed to be non-NULL. */
1088 follow_exec (ptid_t ptid
, char *execd_pathname
)
1090 struct thread_info
*th
, *tmp
;
1091 struct inferior
*inf
= current_inferior ();
1092 int pid
= ptid_get_pid (ptid
);
1093 ptid_t process_ptid
;
1095 /* This is an exec event that we actually wish to pay attention to.
1096 Refresh our symbol table to the newly exec'd program, remove any
1097 momentary bp's, etc.
1099 If there are breakpoints, they aren't really inserted now,
1100 since the exec() transformed our inferior into a fresh set
1103 We want to preserve symbolic breakpoints on the list, since
1104 we have hopes that they can be reset after the new a.out's
1105 symbol table is read.
1107 However, any "raw" breakpoints must be removed from the list
1108 (e.g., the solib bp's), since their address is probably invalid
1111 And, we DON'T want to call delete_breakpoints() here, since
1112 that may write the bp's "shadow contents" (the instruction
1113 value that was overwritten witha TRAP instruction). Since
1114 we now have a new a.out, those shadow contents aren't valid. */
1116 mark_breakpoints_out ();
1118 /* The target reports the exec event to the main thread, even if
1119 some other thread does the exec, and even if the main thread was
1120 stopped or already gone. We may still have non-leader threads of
1121 the process on our list. E.g., on targets that don't have thread
1122 exit events (like remote); or on native Linux in non-stop mode if
1123 there were only two threads in the inferior and the non-leader
1124 one is the one that execs (and nothing forces an update of the
1125 thread list up to here). When debugging remotely, it's best to
1126 avoid extra traffic, when possible, so avoid syncing the thread
1127 list with the target, and instead go ahead and delete all threads
1128 of the process but one that reported the event. Note this must
1129 be done before calling update_breakpoints_after_exec, as
1130 otherwise clearing the threads' resources would reference stale
1131 thread breakpoints -- it may have been one of these threads that
1132 stepped across the exec. We could just clear their stepping
1133 states, but as long as we're iterating, might as well delete
1134 them. Deleting them now rather than at the next user-visible
1135 stop provides a nicer sequence of events for user and MI
1137 ALL_THREADS_SAFE (th
, tmp
)
1138 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1139 delete_thread (th
->ptid
);
1141 /* We also need to clear any left over stale state for the
1142 leader/event thread. E.g., if there was any step-resume
1143 breakpoint or similar, it's gone now. We cannot truly
1144 step-to-next statement through an exec(). */
1145 th
= inferior_thread ();
1146 th
->control
.step_resume_breakpoint
= NULL
;
1147 th
->control
.exception_resume_breakpoint
= NULL
;
1148 th
->control
.single_step_breakpoints
= NULL
;
1149 th
->control
.step_range_start
= 0;
1150 th
->control
.step_range_end
= 0;
1152 /* The user may have had the main thread held stopped in the
1153 previous image (e.g., schedlock on, or non-stop). Release
1155 th
->stop_requested
= 0;
1157 update_breakpoints_after_exec ();
1159 /* What is this a.out's name? */
1160 process_ptid
= pid_to_ptid (pid
);
1161 printf_unfiltered (_("%s is executing new program: %s\n"),
1162 target_pid_to_str (process_ptid
),
1165 /* We've followed the inferior through an exec. Therefore, the
1166 inferior has essentially been killed & reborn. */
1168 gdb_flush (gdb_stdout
);
1170 breakpoint_init_inferior (inf_execd
);
1172 if (*gdb_sysroot
!= '\0')
1174 char *name
= exec_file_find (execd_pathname
, NULL
);
1176 execd_pathname
= (char *) alloca (strlen (name
) + 1);
1177 strcpy (execd_pathname
, name
);
1181 /* Reset the shared library package. This ensures that we get a
1182 shlib event when the child reaches "_start", at which point the
1183 dld will have had a chance to initialize the child. */
1184 /* Also, loading a symbol file below may trigger symbol lookups, and
1185 we don't want those to be satisfied by the libraries of the
1186 previous incarnation of this process. */
1187 no_shared_libraries (NULL
, 0);
1189 if (follow_exec_mode_string
== follow_exec_mode_new
)
1191 /* The user wants to keep the old inferior and program spaces
1192 around. Create a new fresh one, and switch to it. */
1194 /* Do exit processing for the original inferior before adding
1195 the new inferior so we don't have two active inferiors with
1196 the same ptid, which can confuse find_inferior_ptid. */
1197 exit_inferior_num_silent (current_inferior ()->num
);
1199 inf
= add_inferior_with_spaces ();
1201 target_follow_exec (inf
, execd_pathname
);
1203 set_current_inferior (inf
);
1204 set_current_program_space (inf
->pspace
);
1209 /* The old description may no longer be fit for the new image.
1210 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1211 old description; we'll read a new one below. No need to do
1212 this on "follow-exec-mode new", as the old inferior stays
1213 around (its description is later cleared/refetched on
1215 target_clear_description ();
1218 gdb_assert (current_program_space
== inf
->pspace
);
1220 /* That a.out is now the one to use. */
1221 exec_file_attach (execd_pathname
, 0);
1223 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1224 (Position Independent Executable) main symbol file will get applied by
1225 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1226 the breakpoints with the zero displacement. */
1228 symbol_file_add (execd_pathname
,
1230 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
1233 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
1234 set_initial_language ();
1236 /* If the target can specify a description, read it. Must do this
1237 after flipping to the new executable (because the target supplied
1238 description must be compatible with the executable's
1239 architecture, and the old executable may e.g., be 32-bit, while
1240 the new one 64-bit), and before anything involving memory or
1242 target_find_description ();
1244 solib_create_inferior_hook (0);
1246 jit_inferior_created_hook ();
1248 breakpoint_re_set ();
1250 /* Reinsert all breakpoints. (Those which were symbolic have
1251 been reset to the proper address in the new a.out, thanks
1252 to symbol_file_command...). */
1253 insert_breakpoints ();
1255 /* The next resume of this inferior should bring it to the shlib
1256 startup breakpoints. (If the user had also set bp's on
1257 "main" from the old (parent) process, then they'll auto-
1258 matically get reset there in the new process.). */
1261 /* The queue of threads that need to do a step-over operation to get
1262 past e.g., a breakpoint. What technique is used to step over the
1263 breakpoint/watchpoint does not matter -- all threads end up in the
1264 same queue, to maintain rough temporal order of execution, in order
1265 to avoid starvation, otherwise, we could e.g., find ourselves
1266 constantly stepping the same couple threads past their breakpoints
1267 over and over, if the single-step finish fast enough. */
1268 struct thread_info
*step_over_queue_head
;
1270 /* Bit flags indicating what the thread needs to step over. */
1274 /* Step over a breakpoint. */
1275 STEP_OVER_BREAKPOINT
= 1,
1277 /* Step past a non-continuable watchpoint, in order to let the
1278 instruction execute so we can evaluate the watchpoint
1280 STEP_OVER_WATCHPOINT
= 2
1283 /* Info about an instruction that is being stepped over. */
1285 struct step_over_info
1287 /* If we're stepping past a breakpoint, this is the address space
1288 and address of the instruction the breakpoint is set at. We'll
1289 skip inserting all breakpoints here. Valid iff ASPACE is
1291 struct address_space
*aspace
;
1294 /* The instruction being stepped over triggers a nonsteppable
1295 watchpoint. If true, we'll skip inserting watchpoints. */
1296 int nonsteppable_watchpoint_p
;
1299 /* The step-over info of the location that is being stepped over.
1301 Note that with async/breakpoint always-inserted mode, a user might
1302 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1303 being stepped over. As setting a new breakpoint inserts all
1304 breakpoints, we need to make sure the breakpoint being stepped over
1305 isn't inserted then. We do that by only clearing the step-over
1306 info when the step-over is actually finished (or aborted).
1308 Presently GDB can only step over one breakpoint at any given time.
1309 Given threads that can't run code in the same address space as the
1310 breakpoint's can't really miss the breakpoint, GDB could be taught
1311 to step-over at most one breakpoint per address space (so this info
1312 could move to the address space object if/when GDB is extended).
1313 The set of breakpoints being stepped over will normally be much
1314 smaller than the set of all breakpoints, so a flag in the
1315 breakpoint location structure would be wasteful. A separate list
1316 also saves complexity and run-time, as otherwise we'd have to go
1317 through all breakpoint locations clearing their flag whenever we
1318 start a new sequence. Similar considerations weigh against storing
1319 this info in the thread object. Plus, not all step overs actually
1320 have breakpoint locations -- e.g., stepping past a single-step
1321 breakpoint, or stepping to complete a non-continuable
1323 static struct step_over_info step_over_info
;
1325 /* Record the address of the breakpoint/instruction we're currently
1329 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1330 int nonsteppable_watchpoint_p
)
1332 step_over_info
.aspace
= aspace
;
1333 step_over_info
.address
= address
;
1334 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1337 /* Called when we're not longer stepping over a breakpoint / an
1338 instruction, so all breakpoints are free to be (re)inserted. */
1341 clear_step_over_info (void)
1344 fprintf_unfiltered (gdb_stdlog
,
1345 "infrun: clear_step_over_info\n");
1346 step_over_info
.aspace
= NULL
;
1347 step_over_info
.address
= 0;
1348 step_over_info
.nonsteppable_watchpoint_p
= 0;
1354 stepping_past_instruction_at (struct address_space
*aspace
,
1357 return (step_over_info
.aspace
!= NULL
1358 && breakpoint_address_match (aspace
, address
,
1359 step_over_info
.aspace
,
1360 step_over_info
.address
));
1366 stepping_past_nonsteppable_watchpoint (void)
1368 return step_over_info
.nonsteppable_watchpoint_p
;
1371 /* Returns true if step-over info is valid. */
1374 step_over_info_valid_p (void)
1376 return (step_over_info
.aspace
!= NULL
1377 || stepping_past_nonsteppable_watchpoint ());
1381 /* Displaced stepping. */
1383 /* In non-stop debugging mode, we must take special care to manage
1384 breakpoints properly; in particular, the traditional strategy for
1385 stepping a thread past a breakpoint it has hit is unsuitable.
1386 'Displaced stepping' is a tactic for stepping one thread past a
1387 breakpoint it has hit while ensuring that other threads running
1388 concurrently will hit the breakpoint as they should.
1390 The traditional way to step a thread T off a breakpoint in a
1391 multi-threaded program in all-stop mode is as follows:
1393 a0) Initially, all threads are stopped, and breakpoints are not
1395 a1) We single-step T, leaving breakpoints uninserted.
1396 a2) We insert breakpoints, and resume all threads.
1398 In non-stop debugging, however, this strategy is unsuitable: we
1399 don't want to have to stop all threads in the system in order to
1400 continue or step T past a breakpoint. Instead, we use displaced
1403 n0) Initially, T is stopped, other threads are running, and
1404 breakpoints are inserted.
1405 n1) We copy the instruction "under" the breakpoint to a separate
1406 location, outside the main code stream, making any adjustments
1407 to the instruction, register, and memory state as directed by
1409 n2) We single-step T over the instruction at its new location.
1410 n3) We adjust the resulting register and memory state as directed
1411 by T's architecture. This includes resetting T's PC to point
1412 back into the main instruction stream.
1415 This approach depends on the following gdbarch methods:
1417 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1418 indicate where to copy the instruction, and how much space must
1419 be reserved there. We use these in step n1.
1421 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1422 address, and makes any necessary adjustments to the instruction,
1423 register contents, and memory. We use this in step n1.
1425 - gdbarch_displaced_step_fixup adjusts registers and memory after
1426 we have successfuly single-stepped the instruction, to yield the
1427 same effect the instruction would have had if we had executed it
1428 at its original address. We use this in step n3.
1430 - gdbarch_displaced_step_free_closure provides cleanup.
1432 The gdbarch_displaced_step_copy_insn and
1433 gdbarch_displaced_step_fixup functions must be written so that
1434 copying an instruction with gdbarch_displaced_step_copy_insn,
1435 single-stepping across the copied instruction, and then applying
1436 gdbarch_displaced_insn_fixup should have the same effects on the
1437 thread's memory and registers as stepping the instruction in place
1438 would have. Exactly which responsibilities fall to the copy and
1439 which fall to the fixup is up to the author of those functions.
1441 See the comments in gdbarch.sh for details.
1443 Note that displaced stepping and software single-step cannot
1444 currently be used in combination, although with some care I think
1445 they could be made to. Software single-step works by placing
1446 breakpoints on all possible subsequent instructions; if the
1447 displaced instruction is a PC-relative jump, those breakpoints
1448 could fall in very strange places --- on pages that aren't
1449 executable, or at addresses that are not proper instruction
1450 boundaries. (We do generally let other threads run while we wait
1451 to hit the software single-step breakpoint, and they might
1452 encounter such a corrupted instruction.) One way to work around
1453 this would be to have gdbarch_displaced_step_copy_insn fully
1454 simulate the effect of PC-relative instructions (and return NULL)
1455 on architectures that use software single-stepping.
1457 In non-stop mode, we can have independent and simultaneous step
1458 requests, so more than one thread may need to simultaneously step
1459 over a breakpoint. The current implementation assumes there is
1460 only one scratch space per process. In this case, we have to
1461 serialize access to the scratch space. If thread A wants to step
1462 over a breakpoint, but we are currently waiting for some other
1463 thread to complete a displaced step, we leave thread A stopped and
1464 place it in the displaced_step_request_queue. Whenever a displaced
1465 step finishes, we pick the next thread in the queue and start a new
1466 displaced step operation on it. See displaced_step_prepare and
1467 displaced_step_fixup for details. */
1469 /* Per-inferior displaced stepping state. */
1470 struct displaced_step_inferior_state
1472 /* Pointer to next in linked list. */
1473 struct displaced_step_inferior_state
*next
;
1475 /* The process this displaced step state refers to. */
1478 /* True if preparing a displaced step ever failed. If so, we won't
1479 try displaced stepping for this inferior again. */
1482 /* If this is not null_ptid, this is the thread carrying out a
1483 displaced single-step in process PID. This thread's state will
1484 require fixing up once it has completed its step. */
1487 /* The architecture the thread had when we stepped it. */
1488 struct gdbarch
*step_gdbarch
;
1490 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1491 for post-step cleanup. */
1492 struct displaced_step_closure
*step_closure
;
1494 /* The address of the original instruction, and the copy we
1496 CORE_ADDR step_original
, step_copy
;
1498 /* Saved contents of copy area. */
1499 gdb_byte
*step_saved_copy
;
1502 /* The list of states of processes involved in displaced stepping
1504 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1506 /* Get the displaced stepping state of process PID. */
1508 static struct displaced_step_inferior_state
*
1509 get_displaced_stepping_state (int pid
)
1511 struct displaced_step_inferior_state
*state
;
1513 for (state
= displaced_step_inferior_states
;
1515 state
= state
->next
)
1516 if (state
->pid
== pid
)
1522 /* Returns true if any inferior has a thread doing a displaced
1526 displaced_step_in_progress_any_inferior (void)
1528 struct displaced_step_inferior_state
*state
;
1530 for (state
= displaced_step_inferior_states
;
1532 state
= state
->next
)
1533 if (!ptid_equal (state
->step_ptid
, null_ptid
))
1539 /* Return true if thread represented by PTID is doing a displaced
1543 displaced_step_in_progress_thread (ptid_t ptid
)
1545 struct displaced_step_inferior_state
*displaced
;
1547 gdb_assert (!ptid_equal (ptid
, null_ptid
));
1549 displaced
= get_displaced_stepping_state (ptid_get_pid (ptid
));
1551 return (displaced
!= NULL
&& ptid_equal (displaced
->step_ptid
, ptid
));
1554 /* Return true if process PID has a thread doing a displaced step. */
1557 displaced_step_in_progress (int pid
)
1559 struct displaced_step_inferior_state
*displaced
;
1561 displaced
= get_displaced_stepping_state (pid
);
1562 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1568 /* Add a new displaced stepping state for process PID to the displaced
1569 stepping state list, or return a pointer to an already existing
1570 entry, if it already exists. Never returns NULL. */
1572 static struct displaced_step_inferior_state
*
1573 add_displaced_stepping_state (int pid
)
1575 struct displaced_step_inferior_state
*state
;
1577 for (state
= displaced_step_inferior_states
;
1579 state
= state
->next
)
1580 if (state
->pid
== pid
)
1583 state
= XCNEW (struct displaced_step_inferior_state
);
1585 state
->next
= displaced_step_inferior_states
;
1586 displaced_step_inferior_states
= state
;
1591 /* If inferior is in displaced stepping, and ADDR equals to starting address
1592 of copy area, return corresponding displaced_step_closure. Otherwise,
1595 struct displaced_step_closure
*
1596 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1598 struct displaced_step_inferior_state
*displaced
1599 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1601 /* If checking the mode of displaced instruction in copy area. */
1602 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1603 && (displaced
->step_copy
== addr
))
1604 return displaced
->step_closure
;
1609 /* Remove the displaced stepping state of process PID. */
1612 remove_displaced_stepping_state (int pid
)
1614 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1616 gdb_assert (pid
!= 0);
1618 it
= displaced_step_inferior_states
;
1619 prev_next_p
= &displaced_step_inferior_states
;
1624 *prev_next_p
= it
->next
;
1629 prev_next_p
= &it
->next
;
1635 infrun_inferior_exit (struct inferior
*inf
)
1637 remove_displaced_stepping_state (inf
->pid
);
1640 /* If ON, and the architecture supports it, GDB will use displaced
1641 stepping to step over breakpoints. If OFF, or if the architecture
1642 doesn't support it, GDB will instead use the traditional
1643 hold-and-step approach. If AUTO (which is the default), GDB will
1644 decide which technique to use to step over breakpoints depending on
1645 which of all-stop or non-stop mode is active --- displaced stepping
1646 in non-stop mode; hold-and-step in all-stop mode. */
1648 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1651 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1652 struct cmd_list_element
*c
,
1655 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1656 fprintf_filtered (file
,
1657 _("Debugger's willingness to use displaced stepping "
1658 "to step over breakpoints is %s (currently %s).\n"),
1659 value
, target_is_non_stop_p () ? "on" : "off");
1661 fprintf_filtered (file
,
1662 _("Debugger's willingness to use displaced stepping "
1663 "to step over breakpoints is %s.\n"), value
);
1666 /* Return non-zero if displaced stepping can/should be used to step
1667 over breakpoints of thread TP. */
1670 use_displaced_stepping (struct thread_info
*tp
)
1672 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
1673 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1674 struct displaced_step_inferior_state
*displaced_state
;
1676 displaced_state
= get_displaced_stepping_state (ptid_get_pid (tp
->ptid
));
1678 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1679 && target_is_non_stop_p ())
1680 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1681 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1682 && find_record_target () == NULL
1683 && (displaced_state
== NULL
1684 || !displaced_state
->failed_before
));
1687 /* Clean out any stray displaced stepping state. */
1689 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1691 /* Indicate that there is no cleanup pending. */
1692 displaced
->step_ptid
= null_ptid
;
1694 if (displaced
->step_closure
)
1696 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1697 displaced
->step_closure
);
1698 displaced
->step_closure
= NULL
;
1703 displaced_step_clear_cleanup (void *arg
)
1705 struct displaced_step_inferior_state
*state
1706 = (struct displaced_step_inferior_state
*) arg
;
1708 displaced_step_clear (state
);
1711 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1713 displaced_step_dump_bytes (struct ui_file
*file
,
1714 const gdb_byte
*buf
,
1719 for (i
= 0; i
< len
; i
++)
1720 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1721 fputs_unfiltered ("\n", file
);
1724 /* Prepare to single-step, using displaced stepping.
1726 Note that we cannot use displaced stepping when we have a signal to
1727 deliver. If we have a signal to deliver and an instruction to step
1728 over, then after the step, there will be no indication from the
1729 target whether the thread entered a signal handler or ignored the
1730 signal and stepped over the instruction successfully --- both cases
1731 result in a simple SIGTRAP. In the first case we mustn't do a
1732 fixup, and in the second case we must --- but we can't tell which.
1733 Comments in the code for 'random signals' in handle_inferior_event
1734 explain how we handle this case instead.
1736 Returns 1 if preparing was successful -- this thread is going to be
1737 stepped now; 0 if displaced stepping this thread got queued; or -1
1738 if this instruction can't be displaced stepped. */
1741 displaced_step_prepare_throw (ptid_t ptid
)
1743 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1744 struct thread_info
*tp
= find_thread_ptid (ptid
);
1745 struct regcache
*regcache
= get_thread_regcache (ptid
);
1746 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1747 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1748 CORE_ADDR original
, copy
;
1750 struct displaced_step_closure
*closure
;
1751 struct displaced_step_inferior_state
*displaced
;
1754 /* We should never reach this function if the architecture does not
1755 support displaced stepping. */
1756 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1758 /* Nor if the thread isn't meant to step over a breakpoint. */
1759 gdb_assert (tp
->control
.trap_expected
);
1761 /* Disable range stepping while executing in the scratch pad. We
1762 want a single-step even if executing the displaced instruction in
1763 the scratch buffer lands within the stepping range (e.g., a
1765 tp
->control
.may_range_step
= 0;
1767 /* We have to displaced step one thread at a time, as we only have
1768 access to a single scratch space per inferior. */
1770 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1772 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1774 /* Already waiting for a displaced step to finish. Defer this
1775 request and place in queue. */
1777 if (debug_displaced
)
1778 fprintf_unfiltered (gdb_stdlog
,
1779 "displaced: deferring step of %s\n",
1780 target_pid_to_str (ptid
));
1782 thread_step_over_chain_enqueue (tp
);
1787 if (debug_displaced
)
1788 fprintf_unfiltered (gdb_stdlog
,
1789 "displaced: stepping %s now\n",
1790 target_pid_to_str (ptid
));
1793 displaced_step_clear (displaced
);
1795 old_cleanups
= save_inferior_ptid ();
1796 inferior_ptid
= ptid
;
1798 original
= regcache_read_pc (regcache
);
1800 copy
= gdbarch_displaced_step_location (gdbarch
);
1801 len
= gdbarch_max_insn_length (gdbarch
);
1803 if (breakpoint_in_range_p (aspace
, copy
, len
))
1805 /* There's a breakpoint set in the scratch pad location range
1806 (which is usually around the entry point). We'd either
1807 install it before resuming, which would overwrite/corrupt the
1808 scratch pad, or if it was already inserted, this displaced
1809 step would overwrite it. The latter is OK in the sense that
1810 we already assume that no thread is going to execute the code
1811 in the scratch pad range (after initial startup) anyway, but
1812 the former is unacceptable. Simply punt and fallback to
1813 stepping over this breakpoint in-line. */
1814 if (debug_displaced
)
1816 fprintf_unfiltered (gdb_stdlog
,
1817 "displaced: breakpoint set in scratch pad. "
1818 "Stepping over breakpoint in-line instead.\n");
1821 do_cleanups (old_cleanups
);
1825 /* Save the original contents of the copy area. */
1826 displaced
->step_saved_copy
= (gdb_byte
*) xmalloc (len
);
1827 ignore_cleanups
= make_cleanup (free_current_contents
,
1828 &displaced
->step_saved_copy
);
1829 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1831 throw_error (MEMORY_ERROR
,
1832 _("Error accessing memory address %s (%s) for "
1833 "displaced-stepping scratch space."),
1834 paddress (gdbarch
, copy
), safe_strerror (status
));
1835 if (debug_displaced
)
1837 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1838 paddress (gdbarch
, copy
));
1839 displaced_step_dump_bytes (gdb_stdlog
,
1840 displaced
->step_saved_copy
,
1844 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1845 original
, copy
, regcache
);
1846 if (closure
== NULL
)
1848 /* The architecture doesn't know how or want to displaced step
1849 this instruction or instruction sequence. Fallback to
1850 stepping over the breakpoint in-line. */
1851 do_cleanups (old_cleanups
);
1855 /* Save the information we need to fix things up if the step
1857 displaced
->step_ptid
= ptid
;
1858 displaced
->step_gdbarch
= gdbarch
;
1859 displaced
->step_closure
= closure
;
1860 displaced
->step_original
= original
;
1861 displaced
->step_copy
= copy
;
1863 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1865 /* Resume execution at the copy. */
1866 regcache_write_pc (regcache
, copy
);
1868 discard_cleanups (ignore_cleanups
);
1870 do_cleanups (old_cleanups
);
1872 if (debug_displaced
)
1873 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1874 paddress (gdbarch
, copy
));
1879 /* Wrapper for displaced_step_prepare_throw that disabled further
1880 attempts at displaced stepping if we get a memory error. */
1883 displaced_step_prepare (ptid_t ptid
)
1889 prepared
= displaced_step_prepare_throw (ptid
);
1891 CATCH (ex
, RETURN_MASK_ERROR
)
1893 struct displaced_step_inferior_state
*displaced_state
;
1895 if (ex
.error
!= MEMORY_ERROR
)
1896 throw_exception (ex
);
1900 fprintf_unfiltered (gdb_stdlog
,
1901 "infrun: disabling displaced stepping: %s\n",
1905 /* Be verbose if "set displaced-stepping" is "on", silent if
1907 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1909 warning (_("disabling displaced stepping: %s"),
1913 /* Disable further displaced stepping attempts. */
1915 = get_displaced_stepping_state (ptid_get_pid (ptid
));
1916 displaced_state
->failed_before
= 1;
1924 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1925 const gdb_byte
*myaddr
, int len
)
1927 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1929 inferior_ptid
= ptid
;
1930 write_memory (memaddr
, myaddr
, len
);
1931 do_cleanups (ptid_cleanup
);
1934 /* Restore the contents of the copy area for thread PTID. */
1937 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1940 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1942 write_memory_ptid (ptid
, displaced
->step_copy
,
1943 displaced
->step_saved_copy
, len
);
1944 if (debug_displaced
)
1945 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1946 target_pid_to_str (ptid
),
1947 paddress (displaced
->step_gdbarch
,
1948 displaced
->step_copy
));
1951 /* If we displaced stepped an instruction successfully, adjust
1952 registers and memory to yield the same effect the instruction would
1953 have had if we had executed it at its original address, and return
1954 1. If the instruction didn't complete, relocate the PC and return
1955 -1. If the thread wasn't displaced stepping, return 0. */
1958 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1960 struct cleanup
*old_cleanups
;
1961 struct displaced_step_inferior_state
*displaced
1962 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1965 /* Was any thread of this process doing a displaced step? */
1966 if (displaced
== NULL
)
1969 /* Was this event for the pid we displaced? */
1970 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1971 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1974 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1976 displaced_step_restore (displaced
, displaced
->step_ptid
);
1978 /* Fixup may need to read memory/registers. Switch to the thread
1979 that we're fixing up. Also, target_stopped_by_watchpoint checks
1980 the current thread. */
1981 switch_to_thread (event_ptid
);
1983 /* Did the instruction complete successfully? */
1984 if (signal
== GDB_SIGNAL_TRAP
1985 && !(target_stopped_by_watchpoint ()
1986 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1987 || target_have_steppable_watchpoint
)))
1989 /* Fix up the resulting state. */
1990 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1991 displaced
->step_closure
,
1992 displaced
->step_original
,
1993 displaced
->step_copy
,
1994 get_thread_regcache (displaced
->step_ptid
));
1999 /* Since the instruction didn't complete, all we can do is
2001 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
2002 CORE_ADDR pc
= regcache_read_pc (regcache
);
2004 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
2005 regcache_write_pc (regcache
, pc
);
2009 do_cleanups (old_cleanups
);
2011 displaced
->step_ptid
= null_ptid
;
2016 /* Data to be passed around while handling an event. This data is
2017 discarded between events. */
2018 struct execution_control_state
2021 /* The thread that got the event, if this was a thread event; NULL
2023 struct thread_info
*event_thread
;
2025 struct target_waitstatus ws
;
2026 int stop_func_filled_in
;
2027 CORE_ADDR stop_func_start
;
2028 CORE_ADDR stop_func_end
;
2029 const char *stop_func_name
;
2032 /* True if the event thread hit the single-step breakpoint of
2033 another thread. Thus the event doesn't cause a stop, the thread
2034 needs to be single-stepped past the single-step breakpoint before
2035 we can switch back to the original stepping thread. */
2036 int hit_singlestep_breakpoint
;
2039 /* Clear ECS and set it to point at TP. */
2042 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
2044 memset (ecs
, 0, sizeof (*ecs
));
2045 ecs
->event_thread
= tp
;
2046 ecs
->ptid
= tp
->ptid
;
2049 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
2050 static void prepare_to_wait (struct execution_control_state
*ecs
);
2051 static int keep_going_stepped_thread (struct thread_info
*tp
);
2052 static int thread_still_needs_step_over (struct thread_info
*tp
);
2053 static void stop_all_threads (void);
2055 /* Are there any pending step-over requests? If so, run all we can
2056 now and return true. Otherwise, return false. */
2059 start_step_over (void)
2061 struct thread_info
*tp
, *next
;
2063 /* Don't start a new step-over if we already have an in-line
2064 step-over operation ongoing. */
2065 if (step_over_info_valid_p ())
2068 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
2070 struct execution_control_state ecss
;
2071 struct execution_control_state
*ecs
= &ecss
;
2072 enum step_over_what step_what
;
2073 int must_be_in_line
;
2075 next
= thread_step_over_chain_next (tp
);
2077 /* If this inferior already has a displaced step in process,
2078 don't start a new one. */
2079 if (displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2082 step_what
= thread_still_needs_step_over (tp
);
2083 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
2084 || ((step_what
& STEP_OVER_BREAKPOINT
)
2085 && !use_displaced_stepping (tp
)));
2087 /* We currently stop all threads of all processes to step-over
2088 in-line. If we need to start a new in-line step-over, let
2089 any pending displaced steps finish first. */
2090 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
2093 thread_step_over_chain_remove (tp
);
2095 if (step_over_queue_head
== NULL
)
2098 fprintf_unfiltered (gdb_stdlog
,
2099 "infrun: step-over queue now empty\n");
2102 if (tp
->control
.trap_expected
2106 internal_error (__FILE__
, __LINE__
,
2107 "[%s] has inconsistent state: "
2108 "trap_expected=%d, resumed=%d, executing=%d\n",
2109 target_pid_to_str (tp
->ptid
),
2110 tp
->control
.trap_expected
,
2116 fprintf_unfiltered (gdb_stdlog
,
2117 "infrun: resuming [%s] for step-over\n",
2118 target_pid_to_str (tp
->ptid
));
2120 /* keep_going_pass_signal skips the step-over if the breakpoint
2121 is no longer inserted. In all-stop, we want to keep looking
2122 for a thread that needs a step-over instead of resuming TP,
2123 because we wouldn't be able to resume anything else until the
2124 target stops again. In non-stop, the resume always resumes
2125 only TP, so it's OK to let the thread resume freely. */
2126 if (!target_is_non_stop_p () && !step_what
)
2129 switch_to_thread (tp
->ptid
);
2130 reset_ecs (ecs
, tp
);
2131 keep_going_pass_signal (ecs
);
2133 if (!ecs
->wait_some_more
)
2134 error (_("Command aborted."));
2136 gdb_assert (tp
->resumed
);
2138 /* If we started a new in-line step-over, we're done. */
2139 if (step_over_info_valid_p ())
2141 gdb_assert (tp
->control
.trap_expected
);
2145 if (!target_is_non_stop_p ())
2147 /* On all-stop, shouldn't have resumed unless we needed a
2149 gdb_assert (tp
->control
.trap_expected
2150 || tp
->step_after_step_resume_breakpoint
);
2152 /* With remote targets (at least), in all-stop, we can't
2153 issue any further remote commands until the program stops
2158 /* Either the thread no longer needed a step-over, or a new
2159 displaced stepping sequence started. Even in the latter
2160 case, continue looking. Maybe we can also start another
2161 displaced step on a thread of other process. */
2167 /* Update global variables holding ptids to hold NEW_PTID if they were
2168 holding OLD_PTID. */
2170 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2172 struct displaced_step_request
*it
;
2173 struct displaced_step_inferior_state
*displaced
;
2175 if (ptid_equal (inferior_ptid
, old_ptid
))
2176 inferior_ptid
= new_ptid
;
2178 for (displaced
= displaced_step_inferior_states
;
2180 displaced
= displaced
->next
)
2182 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
2183 displaced
->step_ptid
= new_ptid
;
2190 /* Things to clean up if we QUIT out of resume (). */
2192 resume_cleanups (void *ignore
)
2194 if (!ptid_equal (inferior_ptid
, null_ptid
))
2195 delete_single_step_breakpoints (inferior_thread ());
2200 static const char schedlock_off
[] = "off";
2201 static const char schedlock_on
[] = "on";
2202 static const char schedlock_step
[] = "step";
2203 static const char schedlock_replay
[] = "replay";
2204 static const char *const scheduler_enums
[] = {
2211 static const char *scheduler_mode
= schedlock_replay
;
2213 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2214 struct cmd_list_element
*c
, const char *value
)
2216 fprintf_filtered (file
,
2217 _("Mode for locking scheduler "
2218 "during execution is \"%s\".\n"),
2223 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
2225 if (!target_can_lock_scheduler
)
2227 scheduler_mode
= schedlock_off
;
2228 error (_("Target '%s' cannot support this command."), target_shortname
);
2232 /* True if execution commands resume all threads of all processes by
2233 default; otherwise, resume only threads of the current inferior
2235 int sched_multi
= 0;
2237 /* Try to setup for software single stepping over the specified location.
2238 Return 1 if target_resume() should use hardware single step.
2240 GDBARCH the current gdbarch.
2241 PC the location to step over. */
2244 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2248 if (execution_direction
== EXEC_FORWARD
2249 && gdbarch_software_single_step_p (gdbarch
)
2250 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
2260 user_visible_resume_ptid (int step
)
2266 /* With non-stop mode on, threads are always handled
2268 resume_ptid
= inferior_ptid
;
2270 else if ((scheduler_mode
== schedlock_on
)
2271 || (scheduler_mode
== schedlock_step
&& step
))
2273 /* User-settable 'scheduler' mode requires solo thread
2275 resume_ptid
= inferior_ptid
;
2277 else if ((scheduler_mode
== schedlock_replay
)
2278 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2280 /* User-settable 'scheduler' mode requires solo thread resume in replay
2282 resume_ptid
= inferior_ptid
;
2284 else if (!sched_multi
&& target_supports_multi_process ())
2286 /* Resume all threads of the current process (and none of other
2288 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2292 /* Resume all threads of all processes. */
2293 resume_ptid
= RESUME_ALL
;
2299 /* Return a ptid representing the set of threads that we will resume,
2300 in the perspective of the target, assuming run control handling
2301 does not require leaving some threads stopped (e.g., stepping past
2302 breakpoint). USER_STEP indicates whether we're about to start the
2303 target for a stepping command. */
2306 internal_resume_ptid (int user_step
)
2308 /* In non-stop, we always control threads individually. Note that
2309 the target may always work in non-stop mode even with "set
2310 non-stop off", in which case user_visible_resume_ptid could
2311 return a wildcard ptid. */
2312 if (target_is_non_stop_p ())
2313 return inferior_ptid
;
2315 return user_visible_resume_ptid (user_step
);
2318 /* Wrapper for target_resume, that handles infrun-specific
2322 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2324 struct thread_info
*tp
= inferior_thread ();
2326 /* Install inferior's terminal modes. */
2327 target_terminal_inferior ();
2329 /* Avoid confusing the next resume, if the next stop/resume
2330 happens to apply to another thread. */
2331 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2333 /* Advise target which signals may be handled silently.
2335 If we have removed breakpoints because we are stepping over one
2336 in-line (in any thread), we need to receive all signals to avoid
2337 accidentally skipping a breakpoint during execution of a signal
2340 Likewise if we're displaced stepping, otherwise a trap for a
2341 breakpoint in a signal handler might be confused with the
2342 displaced step finishing. We don't make the displaced_step_fixup
2343 step distinguish the cases instead, because:
2345 - a backtrace while stopped in the signal handler would show the
2346 scratch pad as frame older than the signal handler, instead of
2347 the real mainline code.
2349 - when the thread is later resumed, the signal handler would
2350 return to the scratch pad area, which would no longer be
2352 if (step_over_info_valid_p ()
2353 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2354 target_pass_signals (0, NULL
);
2356 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2358 target_resume (resume_ptid
, step
, sig
);
2361 /* Resume the inferior, but allow a QUIT. This is useful if the user
2362 wants to interrupt some lengthy single-stepping operation
2363 (for child processes, the SIGINT goes to the inferior, and so
2364 we get a SIGINT random_signal, but for remote debugging and perhaps
2365 other targets, that's not true).
2367 SIG is the signal to give the inferior (zero for none). */
2369 resume (enum gdb_signal sig
)
2371 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2372 struct regcache
*regcache
= get_current_regcache ();
2373 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2374 struct thread_info
*tp
= inferior_thread ();
2375 CORE_ADDR pc
= regcache_read_pc (regcache
);
2376 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2378 /* This represents the user's step vs continue request. When
2379 deciding whether "set scheduler-locking step" applies, it's the
2380 user's intention that counts. */
2381 const int user_step
= tp
->control
.stepping_command
;
2382 /* This represents what we'll actually request the target to do.
2383 This can decay from a step to a continue, if e.g., we need to
2384 implement single-stepping with breakpoints (software
2388 gdb_assert (!thread_is_in_step_over_chain (tp
));
2392 if (tp
->suspend
.waitstatus_pending_p
)
2398 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2399 fprintf_unfiltered (gdb_stdlog
,
2400 "infrun: resume: thread %s has pending wait status %s "
2401 "(currently_stepping=%d).\n",
2402 target_pid_to_str (tp
->ptid
), statstr
,
2403 currently_stepping (tp
));
2409 /* FIXME: What should we do if we are supposed to resume this
2410 thread with a signal? Maybe we should maintain a queue of
2411 pending signals to deliver. */
2412 if (sig
!= GDB_SIGNAL_0
)
2414 warning (_("Couldn't deliver signal %s to %s."),
2415 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2418 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2419 discard_cleanups (old_cleanups
);
2421 if (target_can_async_p ())
2426 tp
->stepped_breakpoint
= 0;
2428 /* Depends on stepped_breakpoint. */
2429 step
= currently_stepping (tp
);
2431 if (current_inferior ()->waiting_for_vfork_done
)
2433 /* Don't try to single-step a vfork parent that is waiting for
2434 the child to get out of the shared memory region (by exec'ing
2435 or exiting). This is particularly important on software
2436 single-step archs, as the child process would trip on the
2437 software single step breakpoint inserted for the parent
2438 process. Since the parent will not actually execute any
2439 instruction until the child is out of the shared region (such
2440 are vfork's semantics), it is safe to simply continue it.
2441 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2442 the parent, and tell it to `keep_going', which automatically
2443 re-sets it stepping. */
2445 fprintf_unfiltered (gdb_stdlog
,
2446 "infrun: resume : clear step\n");
2451 fprintf_unfiltered (gdb_stdlog
,
2452 "infrun: resume (step=%d, signal=%s), "
2453 "trap_expected=%d, current thread [%s] at %s\n",
2454 step
, gdb_signal_to_symbol_string (sig
),
2455 tp
->control
.trap_expected
,
2456 target_pid_to_str (inferior_ptid
),
2457 paddress (gdbarch
, pc
));
2459 /* Normally, by the time we reach `resume', the breakpoints are either
2460 removed or inserted, as appropriate. The exception is if we're sitting
2461 at a permanent breakpoint; we need to step over it, but permanent
2462 breakpoints can't be removed. So we have to test for it here. */
2463 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2465 if (sig
!= GDB_SIGNAL_0
)
2467 /* We have a signal to pass to the inferior. The resume
2468 may, or may not take us to the signal handler. If this
2469 is a step, we'll need to stop in the signal handler, if
2470 there's one, (if the target supports stepping into
2471 handlers), or in the next mainline instruction, if
2472 there's no handler. If this is a continue, we need to be
2473 sure to run the handler with all breakpoints inserted.
2474 In all cases, set a breakpoint at the current address
2475 (where the handler returns to), and once that breakpoint
2476 is hit, resume skipping the permanent breakpoint. If
2477 that breakpoint isn't hit, then we've stepped into the
2478 signal handler (or hit some other event). We'll delete
2479 the step-resume breakpoint then. */
2482 fprintf_unfiltered (gdb_stdlog
,
2483 "infrun: resume: skipping permanent breakpoint, "
2484 "deliver signal first\n");
2486 clear_step_over_info ();
2487 tp
->control
.trap_expected
= 0;
2489 if (tp
->control
.step_resume_breakpoint
== NULL
)
2491 /* Set a "high-priority" step-resume, as we don't want
2492 user breakpoints at PC to trigger (again) when this
2494 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2495 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2497 tp
->step_after_step_resume_breakpoint
= step
;
2500 insert_breakpoints ();
2504 /* There's no signal to pass, we can go ahead and skip the
2505 permanent breakpoint manually. */
2507 fprintf_unfiltered (gdb_stdlog
,
2508 "infrun: resume: skipping permanent breakpoint\n");
2509 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2510 /* Update pc to reflect the new address from which we will
2511 execute instructions. */
2512 pc
= regcache_read_pc (regcache
);
2516 /* We've already advanced the PC, so the stepping part
2517 is done. Now we need to arrange for a trap to be
2518 reported to handle_inferior_event. Set a breakpoint
2519 at the current PC, and run to it. Don't update
2520 prev_pc, because if we end in
2521 switch_back_to_stepped_thread, we want the "expected
2522 thread advanced also" branch to be taken. IOW, we
2523 don't want this thread to step further from PC
2525 gdb_assert (!step_over_info_valid_p ());
2526 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2527 insert_breakpoints ();
2529 resume_ptid
= internal_resume_ptid (user_step
);
2530 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2531 discard_cleanups (old_cleanups
);
2538 /* If we have a breakpoint to step over, make sure to do a single
2539 step only. Same if we have software watchpoints. */
2540 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2541 tp
->control
.may_range_step
= 0;
2543 /* If enabled, step over breakpoints by executing a copy of the
2544 instruction at a different address.
2546 We can't use displaced stepping when we have a signal to deliver;
2547 the comments for displaced_step_prepare explain why. The
2548 comments in the handle_inferior event for dealing with 'random
2549 signals' explain what we do instead.
2551 We can't use displaced stepping when we are waiting for vfork_done
2552 event, displaced stepping breaks the vfork child similarly as single
2553 step software breakpoint. */
2554 if (tp
->control
.trap_expected
2555 && use_displaced_stepping (tp
)
2556 && !step_over_info_valid_p ()
2557 && sig
== GDB_SIGNAL_0
2558 && !current_inferior ()->waiting_for_vfork_done
)
2560 int prepared
= displaced_step_prepare (inferior_ptid
);
2565 fprintf_unfiltered (gdb_stdlog
,
2566 "Got placed in step-over queue\n");
2568 tp
->control
.trap_expected
= 0;
2569 discard_cleanups (old_cleanups
);
2572 else if (prepared
< 0)
2574 /* Fallback to stepping over the breakpoint in-line. */
2576 if (target_is_non_stop_p ())
2577 stop_all_threads ();
2579 set_step_over_info (get_regcache_aspace (regcache
),
2580 regcache_read_pc (regcache
), 0);
2582 step
= maybe_software_singlestep (gdbarch
, pc
);
2584 insert_breakpoints ();
2586 else if (prepared
> 0)
2588 struct displaced_step_inferior_state
*displaced
;
2590 /* Update pc to reflect the new address from which we will
2591 execute instructions due to displaced stepping. */
2592 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2594 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2595 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2596 displaced
->step_closure
);
2600 /* Do we need to do it the hard way, w/temp breakpoints? */
2602 step
= maybe_software_singlestep (gdbarch
, pc
);
2604 /* Currently, our software single-step implementation leads to different
2605 results than hardware single-stepping in one situation: when stepping
2606 into delivering a signal which has an associated signal handler,
2607 hardware single-step will stop at the first instruction of the handler,
2608 while software single-step will simply skip execution of the handler.
2610 For now, this difference in behavior is accepted since there is no
2611 easy way to actually implement single-stepping into a signal handler
2612 without kernel support.
2614 However, there is one scenario where this difference leads to follow-on
2615 problems: if we're stepping off a breakpoint by removing all breakpoints
2616 and then single-stepping. In this case, the software single-step
2617 behavior means that even if there is a *breakpoint* in the signal
2618 handler, GDB still would not stop.
2620 Fortunately, we can at least fix this particular issue. We detect
2621 here the case where we are about to deliver a signal while software
2622 single-stepping with breakpoints removed. In this situation, we
2623 revert the decisions to remove all breakpoints and insert single-
2624 step breakpoints, and instead we install a step-resume breakpoint
2625 at the current address, deliver the signal without stepping, and
2626 once we arrive back at the step-resume breakpoint, actually step
2627 over the breakpoint we originally wanted to step over. */
2628 if (thread_has_single_step_breakpoints_set (tp
)
2629 && sig
!= GDB_SIGNAL_0
2630 && step_over_info_valid_p ())
2632 /* If we have nested signals or a pending signal is delivered
2633 immediately after a handler returns, might might already have
2634 a step-resume breakpoint set on the earlier handler. We cannot
2635 set another step-resume breakpoint; just continue on until the
2636 original breakpoint is hit. */
2637 if (tp
->control
.step_resume_breakpoint
== NULL
)
2639 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2640 tp
->step_after_step_resume_breakpoint
= 1;
2643 delete_single_step_breakpoints (tp
);
2645 clear_step_over_info ();
2646 tp
->control
.trap_expected
= 0;
2648 insert_breakpoints ();
2651 /* If STEP is set, it's a request to use hardware stepping
2652 facilities. But in that case, we should never
2653 use singlestep breakpoint. */
2654 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2656 /* Decide the set of threads to ask the target to resume. */
2657 if ((step
|| thread_has_single_step_breakpoints_set (tp
))
2658 && tp
->control
.trap_expected
)
2660 /* We're allowing a thread to run past a breakpoint it has
2661 hit, by single-stepping the thread with the breakpoint
2662 removed. In which case, we need to single-step only this
2663 thread, and keep others stopped, as they can miss this
2664 breakpoint if allowed to run. */
2665 resume_ptid
= inferior_ptid
;
2668 resume_ptid
= internal_resume_ptid (user_step
);
2670 if (execution_direction
!= EXEC_REVERSE
2671 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2673 /* There are two cases where we currently need to step a
2674 breakpoint instruction when we have a signal to deliver:
2676 - See handle_signal_stop where we handle random signals that
2677 could take out us out of the stepping range. Normally, in
2678 that case we end up continuing (instead of stepping) over the
2679 signal handler with a breakpoint at PC, but there are cases
2680 where we should _always_ single-step, even if we have a
2681 step-resume breakpoint, like when a software watchpoint is
2682 set. Assuming single-stepping and delivering a signal at the
2683 same time would takes us to the signal handler, then we could
2684 have removed the breakpoint at PC to step over it. However,
2685 some hardware step targets (like e.g., Mac OS) can't step
2686 into signal handlers, and for those, we need to leave the
2687 breakpoint at PC inserted, as otherwise if the handler
2688 recurses and executes PC again, it'll miss the breakpoint.
2689 So we leave the breakpoint inserted anyway, but we need to
2690 record that we tried to step a breakpoint instruction, so
2691 that adjust_pc_after_break doesn't end up confused.
2693 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2694 in one thread after another thread that was stepping had been
2695 momentarily paused for a step-over. When we re-resume the
2696 stepping thread, it may be resumed from that address with a
2697 breakpoint that hasn't trapped yet. Seen with
2698 gdb.threads/non-stop-fair-events.exp, on targets that don't
2699 do displaced stepping. */
2702 fprintf_unfiltered (gdb_stdlog
,
2703 "infrun: resume: [%s] stepped breakpoint\n",
2704 target_pid_to_str (tp
->ptid
));
2706 tp
->stepped_breakpoint
= 1;
2708 /* Most targets can step a breakpoint instruction, thus
2709 executing it normally. But if this one cannot, just
2710 continue and we will hit it anyway. */
2711 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2716 && tp
->control
.trap_expected
2717 && use_displaced_stepping (tp
)
2718 && !step_over_info_valid_p ())
2720 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2721 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2722 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2725 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2726 paddress (resume_gdbarch
, actual_pc
));
2727 read_memory (actual_pc
, buf
, sizeof (buf
));
2728 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2731 if (tp
->control
.may_range_step
)
2733 /* If we're resuming a thread with the PC out of the step
2734 range, then we're doing some nested/finer run control
2735 operation, like stepping the thread out of the dynamic
2736 linker or the displaced stepping scratch pad. We
2737 shouldn't have allowed a range step then. */
2738 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2741 do_target_resume (resume_ptid
, step
, sig
);
2743 discard_cleanups (old_cleanups
);
2750 /* Counter that tracks number of user visible stops. This can be used
2751 to tell whether a command has proceeded the inferior past the
2752 current location. This allows e.g., inferior function calls in
2753 breakpoint commands to not interrupt the command list. When the
2754 call finishes successfully, the inferior is standing at the same
2755 breakpoint as if nothing happened (and so we don't call
2757 static ULONGEST current_stop_id
;
2764 return current_stop_id
;
2767 /* Called when we report a user visible stop. */
2775 /* Clear out all variables saying what to do when inferior is continued.
2776 First do this, then set the ones you want, then call `proceed'. */
2779 clear_proceed_status_thread (struct thread_info
*tp
)
2782 fprintf_unfiltered (gdb_stdlog
,
2783 "infrun: clear_proceed_status_thread (%s)\n",
2784 target_pid_to_str (tp
->ptid
));
2786 /* If we're starting a new sequence, then the previous finished
2787 single-step is no longer relevant. */
2788 if (tp
->suspend
.waitstatus_pending_p
)
2790 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2793 fprintf_unfiltered (gdb_stdlog
,
2794 "infrun: clear_proceed_status: pending "
2795 "event of %s was a finished step. "
2797 target_pid_to_str (tp
->ptid
));
2799 tp
->suspend
.waitstatus_pending_p
= 0;
2800 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2802 else if (debug_infrun
)
2806 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2807 fprintf_unfiltered (gdb_stdlog
,
2808 "infrun: clear_proceed_status_thread: thread %s "
2809 "has pending wait status %s "
2810 "(currently_stepping=%d).\n",
2811 target_pid_to_str (tp
->ptid
), statstr
,
2812 currently_stepping (tp
));
2817 /* If this signal should not be seen by program, give it zero.
2818 Used for debugging signals. */
2819 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2820 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2822 thread_fsm_delete (tp
->thread_fsm
);
2823 tp
->thread_fsm
= NULL
;
2825 tp
->control
.trap_expected
= 0;
2826 tp
->control
.step_range_start
= 0;
2827 tp
->control
.step_range_end
= 0;
2828 tp
->control
.may_range_step
= 0;
2829 tp
->control
.step_frame_id
= null_frame_id
;
2830 tp
->control
.step_stack_frame_id
= null_frame_id
;
2831 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2832 tp
->control
.step_start_function
= NULL
;
2833 tp
->stop_requested
= 0;
2835 tp
->control
.stop_step
= 0;
2837 tp
->control
.proceed_to_finish
= 0;
2839 tp
->control
.command_interp
= NULL
;
2840 tp
->control
.stepping_command
= 0;
2842 /* Discard any remaining commands or status from previous stop. */
2843 bpstat_clear (&tp
->control
.stop_bpstat
);
2847 clear_proceed_status (int step
)
2849 /* With scheduler-locking replay, stop replaying other threads if we're
2850 not replaying the user-visible resume ptid.
2852 This is a convenience feature to not require the user to explicitly
2853 stop replaying the other threads. We're assuming that the user's
2854 intent is to resume tracing the recorded process. */
2855 if (!non_stop
&& scheduler_mode
== schedlock_replay
2856 && target_record_is_replaying (minus_one_ptid
)
2857 && !target_record_will_replay (user_visible_resume_ptid (step
),
2858 execution_direction
))
2859 target_record_stop_replaying ();
2863 struct thread_info
*tp
;
2866 resume_ptid
= user_visible_resume_ptid (step
);
2868 /* In all-stop mode, delete the per-thread status of all threads
2869 we're about to resume, implicitly and explicitly. */
2870 ALL_NON_EXITED_THREADS (tp
)
2872 if (!ptid_match (tp
->ptid
, resume_ptid
))
2874 clear_proceed_status_thread (tp
);
2878 if (!ptid_equal (inferior_ptid
, null_ptid
))
2880 struct inferior
*inferior
;
2884 /* If in non-stop mode, only delete the per-thread status of
2885 the current thread. */
2886 clear_proceed_status_thread (inferior_thread ());
2889 inferior
= current_inferior ();
2890 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2893 observer_notify_about_to_proceed ();
2896 /* Returns true if TP is still stopped at a breakpoint that needs
2897 stepping-over in order to make progress. If the breakpoint is gone
2898 meanwhile, we can skip the whole step-over dance. */
2901 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2903 if (tp
->stepping_over_breakpoint
)
2905 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2907 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2908 regcache_read_pc (regcache
))
2909 == ordinary_breakpoint_here
)
2912 tp
->stepping_over_breakpoint
= 0;
2918 /* Check whether thread TP still needs to start a step-over in order
2919 to make progress when resumed. Returns an bitwise or of enum
2920 step_over_what bits, indicating what needs to be stepped over. */
2923 thread_still_needs_step_over (struct thread_info
*tp
)
2925 struct inferior
*inf
= find_inferior_ptid (tp
->ptid
);
2928 if (thread_still_needs_step_over_bp (tp
))
2929 what
|= STEP_OVER_BREAKPOINT
;
2931 if (tp
->stepping_over_watchpoint
2932 && !target_have_steppable_watchpoint
)
2933 what
|= STEP_OVER_WATCHPOINT
;
2938 /* Returns true if scheduler locking applies. STEP indicates whether
2939 we're about to do a step/next-like command to a thread. */
2942 schedlock_applies (struct thread_info
*tp
)
2944 return (scheduler_mode
== schedlock_on
2945 || (scheduler_mode
== schedlock_step
2946 && tp
->control
.stepping_command
)
2947 || (scheduler_mode
== schedlock_replay
2948 && target_record_will_replay (minus_one_ptid
,
2949 execution_direction
)));
2952 /* Basic routine for continuing the program in various fashions.
2954 ADDR is the address to resume at, or -1 for resume where stopped.
2955 SIGGNAL is the signal to give it, or 0 for none,
2956 or -1 for act according to how it stopped.
2957 STEP is nonzero if should trap after one instruction.
2958 -1 means return after that and print nothing.
2959 You should probably set various step_... variables
2960 before calling here, if you are stepping.
2962 You should call clear_proceed_status before calling proceed. */
2965 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2967 struct regcache
*regcache
;
2968 struct gdbarch
*gdbarch
;
2969 struct thread_info
*tp
;
2971 struct address_space
*aspace
;
2973 struct execution_control_state ecss
;
2974 struct execution_control_state
*ecs
= &ecss
;
2975 struct cleanup
*old_chain
;
2978 /* If we're stopped at a fork/vfork, follow the branch set by the
2979 "set follow-fork-mode" command; otherwise, we'll just proceed
2980 resuming the current thread. */
2981 if (!follow_fork ())
2983 /* The target for some reason decided not to resume. */
2985 if (target_can_async_p ())
2986 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2990 /* We'll update this if & when we switch to a new thread. */
2991 previous_inferior_ptid
= inferior_ptid
;
2993 regcache
= get_current_regcache ();
2994 gdbarch
= get_regcache_arch (regcache
);
2995 aspace
= get_regcache_aspace (regcache
);
2996 pc
= regcache_read_pc (regcache
);
2997 tp
= inferior_thread ();
2999 /* Fill in with reasonable starting values. */
3000 init_thread_stepping_state (tp
);
3002 gdb_assert (!thread_is_in_step_over_chain (tp
));
3004 if (addr
== (CORE_ADDR
) -1)
3007 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3008 && execution_direction
!= EXEC_REVERSE
)
3009 /* There is a breakpoint at the address we will resume at,
3010 step one instruction before inserting breakpoints so that
3011 we do not stop right away (and report a second hit at this
3014 Note, we don't do this in reverse, because we won't
3015 actually be executing the breakpoint insn anyway.
3016 We'll be (un-)executing the previous instruction. */
3017 tp
->stepping_over_breakpoint
= 1;
3018 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3019 && gdbarch_single_step_through_delay (gdbarch
,
3020 get_current_frame ()))
3021 /* We stepped onto an instruction that needs to be stepped
3022 again before re-inserting the breakpoint, do so. */
3023 tp
->stepping_over_breakpoint
= 1;
3027 regcache_write_pc (regcache
, addr
);
3030 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3031 tp
->suspend
.stop_signal
= siggnal
;
3033 /* Record the interpreter that issued the execution command that
3034 caused this thread to resume. If the top level interpreter is
3035 MI/async, and the execution command was a CLI command
3036 (next/step/etc.), we'll want to print stop event output to the MI
3037 console channel (the stepped-to line, etc.), as if the user
3038 entered the execution command on a real GDB console. */
3039 tp
->control
.command_interp
= command_interp ();
3041 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3043 /* If an exception is thrown from this point on, make sure to
3044 propagate GDB's knowledge of the executing state to the
3045 frontend/user running state. */
3046 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3048 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3049 threads (e.g., we might need to set threads stepping over
3050 breakpoints first), from the user/frontend's point of view, all
3051 threads in RESUME_PTID are now running. Unless we're calling an
3052 inferior function, as in that case we pretend the inferior
3053 doesn't run at all. */
3054 if (!tp
->control
.in_infcall
)
3055 set_running (resume_ptid
, 1);
3058 fprintf_unfiltered (gdb_stdlog
,
3059 "infrun: proceed (addr=%s, signal=%s)\n",
3060 paddress (gdbarch
, addr
),
3061 gdb_signal_to_symbol_string (siggnal
));
3063 annotate_starting ();
3065 /* Make sure that output from GDB appears before output from the
3067 gdb_flush (gdb_stdout
);
3069 /* In a multi-threaded task we may select another thread and
3070 then continue or step.
3072 But if a thread that we're resuming had stopped at a breakpoint,
3073 it will immediately cause another breakpoint stop without any
3074 execution (i.e. it will report a breakpoint hit incorrectly). So
3075 we must step over it first.
3077 Look for threads other than the current (TP) that reported a
3078 breakpoint hit and haven't been resumed yet since. */
3080 /* If scheduler locking applies, we can avoid iterating over all
3082 if (!non_stop
&& !schedlock_applies (tp
))
3084 struct thread_info
*current
= tp
;
3086 ALL_NON_EXITED_THREADS (tp
)
3088 /* Ignore the current thread here. It's handled
3093 /* Ignore threads of processes we're not resuming. */
3094 if (!ptid_match (tp
->ptid
, resume_ptid
))
3097 if (!thread_still_needs_step_over (tp
))
3100 gdb_assert (!thread_is_in_step_over_chain (tp
));
3103 fprintf_unfiltered (gdb_stdlog
,
3104 "infrun: need to step-over [%s] first\n",
3105 target_pid_to_str (tp
->ptid
));
3107 thread_step_over_chain_enqueue (tp
);
3113 /* Enqueue the current thread last, so that we move all other
3114 threads over their breakpoints first. */
3115 if (tp
->stepping_over_breakpoint
)
3116 thread_step_over_chain_enqueue (tp
);
3118 /* If the thread isn't started, we'll still need to set its prev_pc,
3119 so that switch_back_to_stepped_thread knows the thread hasn't
3120 advanced. Must do this before resuming any thread, as in
3121 all-stop/remote, once we resume we can't send any other packet
3122 until the target stops again. */
3123 tp
->prev_pc
= regcache_read_pc (regcache
);
3125 started
= start_step_over ();
3127 if (step_over_info_valid_p ())
3129 /* Either this thread started a new in-line step over, or some
3130 other thread was already doing one. In either case, don't
3131 resume anything else until the step-over is finished. */
3133 else if (started
&& !target_is_non_stop_p ())
3135 /* A new displaced stepping sequence was started. In all-stop,
3136 we can't talk to the target anymore until it next stops. */
3138 else if (!non_stop
&& target_is_non_stop_p ())
3140 /* In all-stop, but the target is always in non-stop mode.
3141 Start all other threads that are implicitly resumed too. */
3142 ALL_NON_EXITED_THREADS (tp
)
3144 /* Ignore threads of processes we're not resuming. */
3145 if (!ptid_match (tp
->ptid
, resume_ptid
))
3151 fprintf_unfiltered (gdb_stdlog
,
3152 "infrun: proceed: [%s] resumed\n",
3153 target_pid_to_str (tp
->ptid
));
3154 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3158 if (thread_is_in_step_over_chain (tp
))
3161 fprintf_unfiltered (gdb_stdlog
,
3162 "infrun: proceed: [%s] needs step-over\n",
3163 target_pid_to_str (tp
->ptid
));
3168 fprintf_unfiltered (gdb_stdlog
,
3169 "infrun: proceed: resuming %s\n",
3170 target_pid_to_str (tp
->ptid
));
3172 reset_ecs (ecs
, tp
);
3173 switch_to_thread (tp
->ptid
);
3174 keep_going_pass_signal (ecs
);
3175 if (!ecs
->wait_some_more
)
3176 error (_("Command aborted."));
3179 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3181 /* The thread wasn't started, and isn't queued, run it now. */
3182 reset_ecs (ecs
, tp
);
3183 switch_to_thread (tp
->ptid
);
3184 keep_going_pass_signal (ecs
);
3185 if (!ecs
->wait_some_more
)
3186 error (_("Command aborted."));
3189 discard_cleanups (old_chain
);
3191 /* Tell the event loop to wait for it to stop. If the target
3192 supports asynchronous execution, it'll do this from within
3194 if (!target_can_async_p ())
3195 mark_async_event_handler (infrun_async_inferior_event_token
);
3199 /* Start remote-debugging of a machine over a serial link. */
3202 start_remote (int from_tty
)
3204 struct inferior
*inferior
;
3206 inferior
= current_inferior ();
3207 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3209 /* Always go on waiting for the target, regardless of the mode. */
3210 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3211 indicate to wait_for_inferior that a target should timeout if
3212 nothing is returned (instead of just blocking). Because of this,
3213 targets expecting an immediate response need to, internally, set
3214 things up so that the target_wait() is forced to eventually
3216 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3217 differentiate to its caller what the state of the target is after
3218 the initial open has been performed. Here we're assuming that
3219 the target has stopped. It should be possible to eventually have
3220 target_open() return to the caller an indication that the target
3221 is currently running and GDB state should be set to the same as
3222 for an async run. */
3223 wait_for_inferior ();
3225 /* Now that the inferior has stopped, do any bookkeeping like
3226 loading shared libraries. We want to do this before normal_stop,
3227 so that the displayed frame is up to date. */
3228 post_create_inferior (¤t_target
, from_tty
);
3233 /* Initialize static vars when a new inferior begins. */
3236 init_wait_for_inferior (void)
3238 /* These are meaningless until the first time through wait_for_inferior. */
3240 breakpoint_init_inferior (inf_starting
);
3242 clear_proceed_status (0);
3244 target_last_wait_ptid
= minus_one_ptid
;
3246 previous_inferior_ptid
= inferior_ptid
;
3248 /* Discard any skipped inlined frames. */
3249 clear_inline_frame_state (minus_one_ptid
);
3254 static void handle_inferior_event (struct execution_control_state
*ecs
);
3256 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3257 struct execution_control_state
*ecs
);
3258 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3259 struct execution_control_state
*ecs
);
3260 static void handle_signal_stop (struct execution_control_state
*ecs
);
3261 static void check_exception_resume (struct execution_control_state
*,
3262 struct frame_info
*);
3264 static void end_stepping_range (struct execution_control_state
*ecs
);
3265 static void stop_waiting (struct execution_control_state
*ecs
);
3266 static void keep_going (struct execution_control_state
*ecs
);
3267 static void process_event_stop_test (struct execution_control_state
*ecs
);
3268 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3270 /* Callback for iterate over threads. If the thread is stopped, but
3271 the user/frontend doesn't know about that yet, go through
3272 normal_stop, as if the thread had just stopped now. ARG points at
3273 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
3274 ptid_is_pid(PTID) is true, applies to all threads of the process
3275 pointed at by PTID. Otherwise, apply only to the thread pointed by
3279 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
3281 ptid_t ptid
= * (ptid_t
*) arg
;
3283 if ((ptid_equal (info
->ptid
, ptid
)
3284 || ptid_equal (minus_one_ptid
, ptid
)
3285 || (ptid_is_pid (ptid
)
3286 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
3287 && is_running (info
->ptid
)
3288 && !is_executing (info
->ptid
))
3290 struct cleanup
*old_chain
;
3291 struct execution_control_state ecss
;
3292 struct execution_control_state
*ecs
= &ecss
;
3294 memset (ecs
, 0, sizeof (*ecs
));
3296 old_chain
= make_cleanup_restore_current_thread ();
3298 overlay_cache_invalid
= 1;
3299 /* Flush target cache before starting to handle each event.
3300 Target was running and cache could be stale. This is just a
3301 heuristic. Running threads may modify target memory, but we
3302 don't get any event. */
3303 target_dcache_invalidate ();
3305 /* Go through handle_inferior_event/normal_stop, so we always
3306 have consistent output as if the stop event had been
3308 ecs
->ptid
= info
->ptid
;
3309 ecs
->event_thread
= info
;
3310 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
3311 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
3313 handle_inferior_event (ecs
);
3315 if (!ecs
->wait_some_more
)
3317 /* Cancel any running execution command. */
3318 thread_cancel_execution_command (info
);
3323 do_cleanups (old_chain
);
3329 /* This function is attached as a "thread_stop_requested" observer.
3330 Cleanup local state that assumed the PTID was to be resumed, and
3331 report the stop to the frontend. */
3334 infrun_thread_stop_requested (ptid_t ptid
)
3336 struct thread_info
*tp
;
3338 /* PTID was requested to stop. Remove matching threads from the
3339 step-over queue, so we don't try to resume them
3341 ALL_NON_EXITED_THREADS (tp
)
3342 if (ptid_match (tp
->ptid
, ptid
))
3344 if (thread_is_in_step_over_chain (tp
))
3345 thread_step_over_chain_remove (tp
);
3348 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
3352 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3354 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3355 nullify_last_target_wait_ptid ();
3358 /* Delete the step resume, single-step and longjmp/exception resume
3359 breakpoints of TP. */
3362 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3364 delete_step_resume_breakpoint (tp
);
3365 delete_exception_resume_breakpoint (tp
);
3366 delete_single_step_breakpoints (tp
);
3369 /* If the target still has execution, call FUNC for each thread that
3370 just stopped. In all-stop, that's all the non-exited threads; in
3371 non-stop, that's the current thread, only. */
3373 typedef void (*for_each_just_stopped_thread_callback_func
)
3374 (struct thread_info
*tp
);
3377 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3379 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3382 if (target_is_non_stop_p ())
3384 /* If in non-stop mode, only the current thread stopped. */
3385 func (inferior_thread ());
3389 struct thread_info
*tp
;
3391 /* In all-stop mode, all threads have stopped. */
3392 ALL_NON_EXITED_THREADS (tp
)
3399 /* Delete the step resume and longjmp/exception resume breakpoints of
3400 the threads that just stopped. */
3403 delete_just_stopped_threads_infrun_breakpoints (void)
3405 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3408 /* Delete the single-step breakpoints of the threads that just
3412 delete_just_stopped_threads_single_step_breakpoints (void)
3414 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3417 /* A cleanup wrapper. */
3420 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3422 delete_just_stopped_threads_infrun_breakpoints ();
3428 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3429 const struct target_waitstatus
*ws
)
3431 char *status_string
= target_waitstatus_to_string (ws
);
3432 struct ui_file
*tmp_stream
= mem_fileopen ();
3435 /* The text is split over several lines because it was getting too long.
3436 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3437 output as a unit; we want only one timestamp printed if debug_timestamp
3440 fprintf_unfiltered (tmp_stream
,
3441 "infrun: target_wait (%d.%ld.%ld",
3442 ptid_get_pid (waiton_ptid
),
3443 ptid_get_lwp (waiton_ptid
),
3444 ptid_get_tid (waiton_ptid
));
3445 if (ptid_get_pid (waiton_ptid
) != -1)
3446 fprintf_unfiltered (tmp_stream
,
3447 " [%s]", target_pid_to_str (waiton_ptid
));
3448 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3449 fprintf_unfiltered (tmp_stream
,
3450 "infrun: %d.%ld.%ld [%s],\n",
3451 ptid_get_pid (result_ptid
),
3452 ptid_get_lwp (result_ptid
),
3453 ptid_get_tid (result_ptid
),
3454 target_pid_to_str (result_ptid
));
3455 fprintf_unfiltered (tmp_stream
,
3459 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3461 /* This uses %s in part to handle %'s in the text, but also to avoid
3462 a gcc error: the format attribute requires a string literal. */
3463 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3465 xfree (status_string
);
3467 ui_file_delete (tmp_stream
);
3470 /* Select a thread at random, out of those which are resumed and have
3473 static struct thread_info
*
3474 random_pending_event_thread (ptid_t waiton_ptid
)
3476 struct thread_info
*event_tp
;
3478 int random_selector
;
3480 /* First see how many events we have. Count only resumed threads
3481 that have an event pending. */
3482 ALL_NON_EXITED_THREADS (event_tp
)
3483 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3484 && event_tp
->resumed
3485 && event_tp
->suspend
.waitstatus_pending_p
)
3488 if (num_events
== 0)
3491 /* Now randomly pick a thread out of those that have had events. */
3492 random_selector
= (int)
3493 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3495 if (debug_infrun
&& num_events
> 1)
3496 fprintf_unfiltered (gdb_stdlog
,
3497 "infrun: Found %d events, selecting #%d\n",
3498 num_events
, random_selector
);
3500 /* Select the Nth thread that has had an event. */
3501 ALL_NON_EXITED_THREADS (event_tp
)
3502 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3503 && event_tp
->resumed
3504 && event_tp
->suspend
.waitstatus_pending_p
)
3505 if (random_selector
-- == 0)
3511 /* Wrapper for target_wait that first checks whether threads have
3512 pending statuses to report before actually asking the target for
3516 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3519 struct thread_info
*tp
;
3521 /* First check if there is a resumed thread with a wait status
3523 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3525 tp
= random_pending_event_thread (ptid
);
3530 fprintf_unfiltered (gdb_stdlog
,
3531 "infrun: Waiting for specific thread %s.\n",
3532 target_pid_to_str (ptid
));
3534 /* We have a specific thread to check. */
3535 tp
= find_thread_ptid (ptid
);
3536 gdb_assert (tp
!= NULL
);
3537 if (!tp
->suspend
.waitstatus_pending_p
)
3542 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3543 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3545 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3546 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3550 pc
= regcache_read_pc (regcache
);
3552 if (pc
!= tp
->suspend
.stop_pc
)
3555 fprintf_unfiltered (gdb_stdlog
,
3556 "infrun: PC of %s changed. was=%s, now=%s\n",
3557 target_pid_to_str (tp
->ptid
),
3558 paddress (gdbarch
, tp
->prev_pc
),
3559 paddress (gdbarch
, pc
));
3562 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3565 fprintf_unfiltered (gdb_stdlog
,
3566 "infrun: previous breakpoint of %s, at %s gone\n",
3567 target_pid_to_str (tp
->ptid
),
3568 paddress (gdbarch
, pc
));
3576 fprintf_unfiltered (gdb_stdlog
,
3577 "infrun: pending event of %s cancelled.\n",
3578 target_pid_to_str (tp
->ptid
));
3580 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3581 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3591 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3592 fprintf_unfiltered (gdb_stdlog
,
3593 "infrun: Using pending wait status %s for %s.\n",
3595 target_pid_to_str (tp
->ptid
));
3599 /* Now that we've selected our final event LWP, un-adjust its PC
3600 if it was a software breakpoint (and the target doesn't
3601 always adjust the PC itself). */
3602 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3603 && !target_supports_stopped_by_sw_breakpoint ())
3605 struct regcache
*regcache
;
3606 struct gdbarch
*gdbarch
;
3609 regcache
= get_thread_regcache (tp
->ptid
);
3610 gdbarch
= get_regcache_arch (regcache
);
3612 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3617 pc
= regcache_read_pc (regcache
);
3618 regcache_write_pc (regcache
, pc
+ decr_pc
);
3622 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3623 *status
= tp
->suspend
.waitstatus
;
3624 tp
->suspend
.waitstatus_pending_p
= 0;
3626 /* Wake up the event loop again, until all pending events are
3628 if (target_is_async_p ())
3629 mark_async_event_handler (infrun_async_inferior_event_token
);
3633 /* But if we don't find one, we'll have to wait. */
3635 if (deprecated_target_wait_hook
)
3636 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3638 event_ptid
= target_wait (ptid
, status
, options
);
3643 /* Prepare and stabilize the inferior for detaching it. E.g.,
3644 detaching while a thread is displaced stepping is a recipe for
3645 crashing it, as nothing would readjust the PC out of the scratch
3649 prepare_for_detach (void)
3651 struct inferior
*inf
= current_inferior ();
3652 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3653 struct cleanup
*old_chain_1
;
3654 struct displaced_step_inferior_state
*displaced
;
3656 displaced
= get_displaced_stepping_state (inf
->pid
);
3658 /* Is any thread of this process displaced stepping? If not,
3659 there's nothing else to do. */
3660 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3664 fprintf_unfiltered (gdb_stdlog
,
3665 "displaced-stepping in-process while detaching");
3667 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3670 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3672 struct cleanup
*old_chain_2
;
3673 struct execution_control_state ecss
;
3674 struct execution_control_state
*ecs
;
3677 memset (ecs
, 0, sizeof (*ecs
));
3679 overlay_cache_invalid
= 1;
3680 /* Flush target cache before starting to handle each event.
3681 Target was running and cache could be stale. This is just a
3682 heuristic. Running threads may modify target memory, but we
3683 don't get any event. */
3684 target_dcache_invalidate ();
3686 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3689 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3691 /* If an error happens while handling the event, propagate GDB's
3692 knowledge of the executing state to the frontend/user running
3694 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3697 /* Now figure out what to do with the result of the result. */
3698 handle_inferior_event (ecs
);
3700 /* No error, don't finish the state yet. */
3701 discard_cleanups (old_chain_2
);
3703 /* Breakpoints and watchpoints are not installed on the target
3704 at this point, and signals are passed directly to the
3705 inferior, so this must mean the process is gone. */
3706 if (!ecs
->wait_some_more
)
3708 discard_cleanups (old_chain_1
);
3709 error (_("Program exited while detaching"));
3713 discard_cleanups (old_chain_1
);
3716 /* Wait for control to return from inferior to debugger.
3718 If inferior gets a signal, we may decide to start it up again
3719 instead of returning. That is why there is a loop in this function.
3720 When this function actually returns it means the inferior
3721 should be left stopped and GDB should read more commands. */
3724 wait_for_inferior (void)
3726 struct cleanup
*old_cleanups
;
3727 struct cleanup
*thread_state_chain
;
3731 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3734 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3737 /* If an error happens while handling the event, propagate GDB's
3738 knowledge of the executing state to the frontend/user running
3740 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3744 struct execution_control_state ecss
;
3745 struct execution_control_state
*ecs
= &ecss
;
3746 ptid_t waiton_ptid
= minus_one_ptid
;
3748 memset (ecs
, 0, sizeof (*ecs
));
3750 overlay_cache_invalid
= 1;
3752 /* Flush target cache before starting to handle each event.
3753 Target was running and cache could be stale. This is just a
3754 heuristic. Running threads may modify target memory, but we
3755 don't get any event. */
3756 target_dcache_invalidate ();
3758 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3761 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3763 /* Now figure out what to do with the result of the result. */
3764 handle_inferior_event (ecs
);
3766 if (!ecs
->wait_some_more
)
3770 /* No error, don't finish the state yet. */
3771 discard_cleanups (thread_state_chain
);
3773 do_cleanups (old_cleanups
);
3776 /* Cleanup that reinstalls the readline callback handler, if the
3777 target is running in the background. If while handling the target
3778 event something triggered a secondary prompt, like e.g., a
3779 pagination prompt, we'll have removed the callback handler (see
3780 gdb_readline_wrapper_line). Need to do this as we go back to the
3781 event loop, ready to process further input. Note this has no
3782 effect if the handler hasn't actually been removed, because calling
3783 rl_callback_handler_install resets the line buffer, thus losing
3787 reinstall_readline_callback_handler_cleanup (void *arg
)
3789 if (!interpreter_async
)
3791 /* We're not going back to the top level event loop yet. Don't
3792 install the readline callback, as it'd prep the terminal,
3793 readline-style (raw, noecho) (e.g., --batch). We'll install
3794 it the next time the prompt is displayed, when we're ready
3799 if (async_command_editing_p
&& !sync_execution
)
3800 gdb_rl_callback_handler_reinstall ();
3803 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3804 that's just the event thread. In all-stop, that's all threads. */
3807 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3809 struct thread_info
*thr
= ecs
->event_thread
;
3811 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3812 thread_fsm_clean_up (thr
->thread_fsm
);
3816 ALL_NON_EXITED_THREADS (thr
)
3818 if (thr
->thread_fsm
== NULL
)
3820 if (thr
== ecs
->event_thread
)
3823 switch_to_thread (thr
->ptid
);
3824 thread_fsm_clean_up (thr
->thread_fsm
);
3827 if (ecs
->event_thread
!= NULL
)
3828 switch_to_thread (ecs
->event_thread
->ptid
);
3832 /* A cleanup that restores the execution direction to the value saved
3836 restore_execution_direction (void *arg
)
3838 enum exec_direction_kind
*save_exec_dir
= (enum exec_direction_kind
*) arg
;
3840 execution_direction
= *save_exec_dir
;
3843 /* Asynchronous version of wait_for_inferior. It is called by the
3844 event loop whenever a change of state is detected on the file
3845 descriptor corresponding to the target. It can be called more than
3846 once to complete a single execution command. In such cases we need
3847 to keep the state in a global variable ECSS. If it is the last time
3848 that this function is called for a single execution command, then
3849 report to the user that the inferior has stopped, and do the
3850 necessary cleanups. */
3853 fetch_inferior_event (void *client_data
)
3855 struct execution_control_state ecss
;
3856 struct execution_control_state
*ecs
= &ecss
;
3857 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3858 struct cleanup
*ts_old_chain
;
3859 int was_sync
= sync_execution
;
3860 enum exec_direction_kind save_exec_dir
= execution_direction
;
3862 ptid_t waiton_ptid
= minus_one_ptid
;
3864 memset (ecs
, 0, sizeof (*ecs
));
3866 /* End up with readline processing input, if necessary. */
3867 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3869 /* We're handling a live event, so make sure we're doing live
3870 debugging. If we're looking at traceframes while the target is
3871 running, we're going to need to get back to that mode after
3872 handling the event. */
3875 make_cleanup_restore_current_traceframe ();
3876 set_current_traceframe (-1);
3880 /* In non-stop mode, the user/frontend should not notice a thread
3881 switch due to internal events. Make sure we reverse to the
3882 user selected thread and frame after handling the event and
3883 running any breakpoint commands. */
3884 make_cleanup_restore_current_thread ();
3886 overlay_cache_invalid
= 1;
3887 /* Flush target cache before starting to handle each event. Target
3888 was running and cache could be stale. This is just a heuristic.
3889 Running threads may modify target memory, but we don't get any
3891 target_dcache_invalidate ();
3893 make_cleanup (restore_execution_direction
, &save_exec_dir
);
3894 execution_direction
= target_execution_direction ();
3896 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3897 target_can_async_p () ? TARGET_WNOHANG
: 0);
3900 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3902 /* If an error happens while handling the event, propagate GDB's
3903 knowledge of the executing state to the frontend/user running
3905 if (!target_is_non_stop_p ())
3906 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3908 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3910 /* Get executed before make_cleanup_restore_current_thread above to apply
3911 still for the thread which has thrown the exception. */
3912 make_bpstat_clear_actions_cleanup ();
3914 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3916 /* Now figure out what to do with the result of the result. */
3917 handle_inferior_event (ecs
);
3919 if (!ecs
->wait_some_more
)
3921 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3922 int should_stop
= 1;
3923 struct thread_info
*thr
= ecs
->event_thread
;
3924 int should_notify_stop
= 1;
3926 delete_just_stopped_threads_infrun_breakpoints ();
3930 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3932 if (thread_fsm
!= NULL
)
3933 should_stop
= thread_fsm_should_stop (thread_fsm
);
3942 clean_up_just_stopped_threads_fsms (ecs
);
3944 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3947 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
3950 if (should_notify_stop
)
3954 /* We may not find an inferior if this was a process exit. */
3955 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3956 proceeded
= normal_stop ();
3960 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3967 /* No error, don't finish the thread states yet. */
3968 discard_cleanups (ts_old_chain
);
3970 /* Revert thread and frame. */
3971 do_cleanups (old_chain
);
3973 /* If the inferior was in sync execution mode, and now isn't,
3974 restore the prompt (a synchronous execution command has finished,
3975 and we're ready for input). */
3976 if (interpreter_async
&& was_sync
&& !sync_execution
)
3977 observer_notify_sync_execution_done ();
3981 && exec_done_display_p
3982 && (ptid_equal (inferior_ptid
, null_ptid
)
3983 || !is_running (inferior_ptid
)))
3984 printf_unfiltered (_("completed.\n"));
3987 /* Record the frame and location we're currently stepping through. */
3989 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3991 struct thread_info
*tp
= inferior_thread ();
3993 tp
->control
.step_frame_id
= get_frame_id (frame
);
3994 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3996 tp
->current_symtab
= sal
.symtab
;
3997 tp
->current_line
= sal
.line
;
4000 /* Clear context switchable stepping state. */
4003 init_thread_stepping_state (struct thread_info
*tss
)
4005 tss
->stepped_breakpoint
= 0;
4006 tss
->stepping_over_breakpoint
= 0;
4007 tss
->stepping_over_watchpoint
= 0;
4008 tss
->step_after_step_resume_breakpoint
= 0;
4011 /* Set the cached copy of the last ptid/waitstatus. */
4014 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
4016 target_last_wait_ptid
= ptid
;
4017 target_last_waitstatus
= status
;
4020 /* Return the cached copy of the last pid/waitstatus returned by
4021 target_wait()/deprecated_target_wait_hook(). The data is actually
4022 cached by handle_inferior_event(), which gets called immediately
4023 after target_wait()/deprecated_target_wait_hook(). */
4026 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
4028 *ptidp
= target_last_wait_ptid
;
4029 *status
= target_last_waitstatus
;
4033 nullify_last_target_wait_ptid (void)
4035 target_last_wait_ptid
= minus_one_ptid
;
4038 /* Switch thread contexts. */
4041 context_switch (ptid_t ptid
)
4043 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4045 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4046 target_pid_to_str (inferior_ptid
));
4047 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4048 target_pid_to_str (ptid
));
4051 switch_to_thread (ptid
);
4054 /* If the target can't tell whether we've hit breakpoints
4055 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4056 check whether that could have been caused by a breakpoint. If so,
4057 adjust the PC, per gdbarch_decr_pc_after_break. */
4060 adjust_pc_after_break (struct thread_info
*thread
,
4061 struct target_waitstatus
*ws
)
4063 struct regcache
*regcache
;
4064 struct gdbarch
*gdbarch
;
4065 struct address_space
*aspace
;
4066 CORE_ADDR breakpoint_pc
, decr_pc
;
4068 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4069 we aren't, just return.
4071 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4072 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4073 implemented by software breakpoints should be handled through the normal
4076 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4077 different signals (SIGILL or SIGEMT for instance), but it is less
4078 clear where the PC is pointing afterwards. It may not match
4079 gdbarch_decr_pc_after_break. I don't know any specific target that
4080 generates these signals at breakpoints (the code has been in GDB since at
4081 least 1992) so I can not guess how to handle them here.
4083 In earlier versions of GDB, a target with
4084 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4085 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4086 target with both of these set in GDB history, and it seems unlikely to be
4087 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4089 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4092 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4095 /* In reverse execution, when a breakpoint is hit, the instruction
4096 under it has already been de-executed. The reported PC always
4097 points at the breakpoint address, so adjusting it further would
4098 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4101 B1 0x08000000 : INSN1
4102 B2 0x08000001 : INSN2
4104 PC -> 0x08000003 : INSN4
4106 Say you're stopped at 0x08000003 as above. Reverse continuing
4107 from that point should hit B2 as below. Reading the PC when the
4108 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4109 been de-executed already.
4111 B1 0x08000000 : INSN1
4112 B2 PC -> 0x08000001 : INSN2
4116 We can't apply the same logic as for forward execution, because
4117 we would wrongly adjust the PC to 0x08000000, since there's a
4118 breakpoint at PC - 1. We'd then report a hit on B1, although
4119 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4121 if (execution_direction
== EXEC_REVERSE
)
4124 /* If the target can tell whether the thread hit a SW breakpoint,
4125 trust it. Targets that can tell also adjust the PC
4127 if (target_supports_stopped_by_sw_breakpoint ())
4130 /* Note that relying on whether a breakpoint is planted in memory to
4131 determine this can fail. E.g,. the breakpoint could have been
4132 removed since. Or the thread could have been told to step an
4133 instruction the size of a breakpoint instruction, and only
4134 _after_ was a breakpoint inserted at its address. */
4136 /* If this target does not decrement the PC after breakpoints, then
4137 we have nothing to do. */
4138 regcache
= get_thread_regcache (thread
->ptid
);
4139 gdbarch
= get_regcache_arch (regcache
);
4141 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4145 aspace
= get_regcache_aspace (regcache
);
4147 /* Find the location where (if we've hit a breakpoint) the
4148 breakpoint would be. */
4149 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4151 /* If the target can't tell whether a software breakpoint triggered,
4152 fallback to figuring it out based on breakpoints we think were
4153 inserted in the target, and on whether the thread was stepped or
4156 /* Check whether there actually is a software breakpoint inserted at
4159 If in non-stop mode, a race condition is possible where we've
4160 removed a breakpoint, but stop events for that breakpoint were
4161 already queued and arrive later. To suppress those spurious
4162 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4163 and retire them after a number of stop events are reported. Note
4164 this is an heuristic and can thus get confused. The real fix is
4165 to get the "stopped by SW BP and needs adjustment" info out of
4166 the target/kernel (and thus never reach here; see above). */
4167 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4168 || (target_is_non_stop_p ()
4169 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4171 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4173 if (record_full_is_used ())
4174 record_full_gdb_operation_disable_set ();
4176 /* When using hardware single-step, a SIGTRAP is reported for both
4177 a completed single-step and a software breakpoint. Need to
4178 differentiate between the two, as the latter needs adjusting
4179 but the former does not.
4181 The SIGTRAP can be due to a completed hardware single-step only if
4182 - we didn't insert software single-step breakpoints
4183 - this thread is currently being stepped
4185 If any of these events did not occur, we must have stopped due
4186 to hitting a software breakpoint, and have to back up to the
4189 As a special case, we could have hardware single-stepped a
4190 software breakpoint. In this case (prev_pc == breakpoint_pc),
4191 we also need to back up to the breakpoint address. */
4193 if (thread_has_single_step_breakpoints_set (thread
)
4194 || !currently_stepping (thread
)
4195 || (thread
->stepped_breakpoint
4196 && thread
->prev_pc
== breakpoint_pc
))
4197 regcache_write_pc (regcache
, breakpoint_pc
);
4199 do_cleanups (old_cleanups
);
4204 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4206 for (frame
= get_prev_frame (frame
);
4208 frame
= get_prev_frame (frame
))
4210 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4212 if (get_frame_type (frame
) != INLINE_FRAME
)
4219 /* Auxiliary function that handles syscall entry/return events.
4220 It returns 1 if the inferior should keep going (and GDB
4221 should ignore the event), or 0 if the event deserves to be
4225 handle_syscall_event (struct execution_control_state
*ecs
)
4227 struct regcache
*regcache
;
4230 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4231 context_switch (ecs
->ptid
);
4233 regcache
= get_thread_regcache (ecs
->ptid
);
4234 syscall_number
= ecs
->ws
.value
.syscall_number
;
4235 stop_pc
= regcache_read_pc (regcache
);
4237 if (catch_syscall_enabled () > 0
4238 && catching_syscall_number (syscall_number
) > 0)
4241 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4244 ecs
->event_thread
->control
.stop_bpstat
4245 = bpstat_stop_status (get_regcache_aspace (regcache
),
4246 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4248 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4250 /* Catchpoint hit. */
4255 /* If no catchpoint triggered for this, then keep going. */
4260 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4263 fill_in_stop_func (struct gdbarch
*gdbarch
,
4264 struct execution_control_state
*ecs
)
4266 if (!ecs
->stop_func_filled_in
)
4268 /* Don't care about return value; stop_func_start and stop_func_name
4269 will both be 0 if it doesn't work. */
4270 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4271 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4272 ecs
->stop_func_start
4273 += gdbarch_deprecated_function_start_offset (gdbarch
);
4275 if (gdbarch_skip_entrypoint_p (gdbarch
))
4276 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4277 ecs
->stop_func_start
);
4279 ecs
->stop_func_filled_in
= 1;
4284 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4286 static enum stop_kind
4287 get_inferior_stop_soon (ptid_t ptid
)
4289 struct inferior
*inf
= find_inferior_ptid (ptid
);
4291 gdb_assert (inf
!= NULL
);
4292 return inf
->control
.stop_soon
;
4295 /* Wait for one event. Store the resulting waitstatus in WS, and
4296 return the event ptid. */
4299 wait_one (struct target_waitstatus
*ws
)
4302 ptid_t wait_ptid
= minus_one_ptid
;
4304 overlay_cache_invalid
= 1;
4306 /* Flush target cache before starting to handle each event.
4307 Target was running and cache could be stale. This is just a
4308 heuristic. Running threads may modify target memory, but we
4309 don't get any event. */
4310 target_dcache_invalidate ();
4312 if (deprecated_target_wait_hook
)
4313 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4315 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4318 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4323 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4324 instead of the current thread. */
4325 #define THREAD_STOPPED_BY(REASON) \
4327 thread_stopped_by_ ## REASON (ptid_t ptid) \
4329 struct cleanup *old_chain; \
4332 old_chain = save_inferior_ptid (); \
4333 inferior_ptid = ptid; \
4335 res = target_stopped_by_ ## REASON (); \
4337 do_cleanups (old_chain); \
4342 /* Generate thread_stopped_by_watchpoint. */
4343 THREAD_STOPPED_BY (watchpoint
)
4344 /* Generate thread_stopped_by_sw_breakpoint. */
4345 THREAD_STOPPED_BY (sw_breakpoint
)
4346 /* Generate thread_stopped_by_hw_breakpoint. */
4347 THREAD_STOPPED_BY (hw_breakpoint
)
4349 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4352 switch_to_thread_cleanup (void *ptid_p
)
4354 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4356 switch_to_thread (ptid
);
4359 /* Save the thread's event and stop reason to process it later. */
4362 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4364 struct regcache
*regcache
;
4365 struct address_space
*aspace
;
4371 statstr
= target_waitstatus_to_string (ws
);
4372 fprintf_unfiltered (gdb_stdlog
,
4373 "infrun: saving status %s for %d.%ld.%ld\n",
4375 ptid_get_pid (tp
->ptid
),
4376 ptid_get_lwp (tp
->ptid
),
4377 ptid_get_tid (tp
->ptid
));
4381 /* Record for later. */
4382 tp
->suspend
.waitstatus
= *ws
;
4383 tp
->suspend
.waitstatus_pending_p
= 1;
4385 regcache
= get_thread_regcache (tp
->ptid
);
4386 aspace
= get_regcache_aspace (regcache
);
4388 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4389 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4391 CORE_ADDR pc
= regcache_read_pc (regcache
);
4393 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4395 if (thread_stopped_by_watchpoint (tp
->ptid
))
4397 tp
->suspend
.stop_reason
4398 = TARGET_STOPPED_BY_WATCHPOINT
;
4400 else if (target_supports_stopped_by_sw_breakpoint ()
4401 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4403 tp
->suspend
.stop_reason
4404 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4406 else if (target_supports_stopped_by_hw_breakpoint ()
4407 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4409 tp
->suspend
.stop_reason
4410 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4412 else if (!target_supports_stopped_by_hw_breakpoint ()
4413 && hardware_breakpoint_inserted_here_p (aspace
,
4416 tp
->suspend
.stop_reason
4417 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4419 else if (!target_supports_stopped_by_sw_breakpoint ()
4420 && software_breakpoint_inserted_here_p (aspace
,
4423 tp
->suspend
.stop_reason
4424 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4426 else if (!thread_has_single_step_breakpoints_set (tp
)
4427 && currently_stepping (tp
))
4429 tp
->suspend
.stop_reason
4430 = TARGET_STOPPED_BY_SINGLE_STEP
;
4435 /* Stop all threads. */
4438 stop_all_threads (void)
4440 /* We may need multiple passes to discover all threads. */
4444 struct cleanup
*old_chain
;
4446 gdb_assert (target_is_non_stop_p ());
4449 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4451 entry_ptid
= inferior_ptid
;
4452 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4454 /* Request threads to stop, and then wait for the stops. Because
4455 threads we already know about can spawn more threads while we're
4456 trying to stop them, and we only learn about new threads when we
4457 update the thread list, do this in a loop, and keep iterating
4458 until two passes find no threads that need to be stopped. */
4459 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4462 fprintf_unfiltered (gdb_stdlog
,
4463 "infrun: stop_all_threads, pass=%d, "
4464 "iterations=%d\n", pass
, iterations
);
4468 struct target_waitstatus ws
;
4470 struct thread_info
*t
;
4472 update_thread_list ();
4474 /* Go through all threads looking for threads that we need
4475 to tell the target to stop. */
4476 ALL_NON_EXITED_THREADS (t
)
4480 /* If already stopping, don't request a stop again.
4481 We just haven't seen the notification yet. */
4482 if (!t
->stop_requested
)
4485 fprintf_unfiltered (gdb_stdlog
,
4486 "infrun: %s executing, "
4488 target_pid_to_str (t
->ptid
));
4489 target_stop (t
->ptid
);
4490 t
->stop_requested
= 1;
4495 fprintf_unfiltered (gdb_stdlog
,
4496 "infrun: %s executing, "
4497 "already stopping\n",
4498 target_pid_to_str (t
->ptid
));
4501 if (t
->stop_requested
)
4507 fprintf_unfiltered (gdb_stdlog
,
4508 "infrun: %s not executing\n",
4509 target_pid_to_str (t
->ptid
));
4511 /* The thread may be not executing, but still be
4512 resumed with a pending status to process. */
4520 /* If we find new threads on the second iteration, restart
4521 over. We want to see two iterations in a row with all
4526 event_ptid
= wait_one (&ws
);
4527 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4529 /* All resumed threads exited. */
4531 else if (ws
.kind
== TARGET_WAITKIND_EXITED
4532 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4536 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4538 fprintf_unfiltered (gdb_stdlog
,
4539 "infrun: %s exited while "
4540 "stopping threads\n",
4541 target_pid_to_str (ptid
));
4546 t
= find_thread_ptid (event_ptid
);
4548 t
= add_thread (event_ptid
);
4550 t
->stop_requested
= 0;
4553 t
->control
.may_range_step
= 0;
4555 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4556 && ws
.value
.sig
== GDB_SIGNAL_0
)
4558 /* We caught the event that we intended to catch, so
4559 there's no event pending. */
4560 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4561 t
->suspend
.waitstatus_pending_p
= 0;
4563 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4565 /* Add it back to the step-over queue. */
4568 fprintf_unfiltered (gdb_stdlog
,
4569 "infrun: displaced-step of %s "
4570 "canceled: adding back to the "
4571 "step-over queue\n",
4572 target_pid_to_str (t
->ptid
));
4574 t
->control
.trap_expected
= 0;
4575 thread_step_over_chain_enqueue (t
);
4580 enum gdb_signal sig
;
4581 struct regcache
*regcache
;
4582 struct address_space
*aspace
;
4588 statstr
= target_waitstatus_to_string (&ws
);
4589 fprintf_unfiltered (gdb_stdlog
,
4590 "infrun: target_wait %s, saving "
4591 "status for %d.%ld.%ld\n",
4593 ptid_get_pid (t
->ptid
),
4594 ptid_get_lwp (t
->ptid
),
4595 ptid_get_tid (t
->ptid
));
4599 /* Record for later. */
4600 save_waitstatus (t
, &ws
);
4602 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4603 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4605 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4607 /* Add it back to the step-over queue. */
4608 t
->control
.trap_expected
= 0;
4609 thread_step_over_chain_enqueue (t
);
4612 regcache
= get_thread_regcache (t
->ptid
);
4613 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4617 fprintf_unfiltered (gdb_stdlog
,
4618 "infrun: saved stop_pc=%s for %s "
4619 "(currently_stepping=%d)\n",
4620 paddress (target_gdbarch (),
4621 t
->suspend
.stop_pc
),
4622 target_pid_to_str (t
->ptid
),
4623 currently_stepping (t
));
4630 do_cleanups (old_chain
);
4633 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4636 /* Given an execution control state that has been freshly filled in by
4637 an event from the inferior, figure out what it means and take
4640 The alternatives are:
4642 1) stop_waiting and return; to really stop and return to the
4645 2) keep_going and return; to wait for the next event (set
4646 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4650 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4652 enum stop_kind stop_soon
;
4654 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4656 /* We had an event in the inferior, but we are not interested in
4657 handling it at this level. The lower layers have already
4658 done what needs to be done, if anything.
4660 One of the possible circumstances for this is when the
4661 inferior produces output for the console. The inferior has
4662 not stopped, and we are ignoring the event. Another possible
4663 circumstance is any event which the lower level knows will be
4664 reported multiple times without an intervening resume. */
4666 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4667 prepare_to_wait (ecs
);
4671 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4672 && target_can_async_p () && !sync_execution
)
4674 /* There were no unwaited-for children left in the target, but,
4675 we're not synchronously waiting for events either. Just
4676 ignore. Otherwise, if we were running a synchronous
4677 execution command, we need to cancel it and give the user
4678 back the terminal. */
4680 fprintf_unfiltered (gdb_stdlog
,
4681 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
4682 prepare_to_wait (ecs
);
4686 /* Cache the last pid/waitstatus. */
4687 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4689 /* Always clear state belonging to the previous time we stopped. */
4690 stop_stack_dummy
= STOP_NONE
;
4692 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4694 /* No unwaited-for children left. IOW, all resumed children
4697 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4699 stop_print_frame
= 0;
4704 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4705 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4707 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4708 /* If it's a new thread, add it to the thread database. */
4709 if (ecs
->event_thread
== NULL
)
4710 ecs
->event_thread
= add_thread (ecs
->ptid
);
4712 /* Disable range stepping. If the next step request could use a
4713 range, this will be end up re-enabled then. */
4714 ecs
->event_thread
->control
.may_range_step
= 0;
4717 /* Dependent on valid ECS->EVENT_THREAD. */
4718 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4720 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4721 reinit_frame_cache ();
4723 breakpoint_retire_moribund ();
4725 /* First, distinguish signals caused by the debugger from signals
4726 that have to do with the program's own actions. Note that
4727 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4728 on the operating system version. Here we detect when a SIGILL or
4729 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4730 something similar for SIGSEGV, since a SIGSEGV will be generated
4731 when we're trying to execute a breakpoint instruction on a
4732 non-executable stack. This happens for call dummy breakpoints
4733 for architectures like SPARC that place call dummies on the
4735 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4736 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4737 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4738 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4740 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4742 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4743 regcache_read_pc (regcache
)))
4746 fprintf_unfiltered (gdb_stdlog
,
4747 "infrun: Treating signal as SIGTRAP\n");
4748 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4752 /* Mark the non-executing threads accordingly. In all-stop, all
4753 threads of all processes are stopped when we get any event
4754 reported. In non-stop mode, only the event thread stops. */
4758 if (!target_is_non_stop_p ())
4759 mark_ptid
= minus_one_ptid
;
4760 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4761 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4763 /* If we're handling a process exit in non-stop mode, even
4764 though threads haven't been deleted yet, one would think
4765 that there is nothing to do, as threads of the dead process
4766 will be soon deleted, and threads of any other process were
4767 left running. However, on some targets, threads survive a
4768 process exit event. E.g., for the "checkpoint" command,
4769 when the current checkpoint/fork exits, linux-fork.c
4770 automatically switches to another fork from within
4771 target_mourn_inferior, by associating the same
4772 inferior/thread to another fork. We haven't mourned yet at
4773 this point, but we must mark any threads left in the
4774 process as not-executing so that finish_thread_state marks
4775 them stopped (in the user's perspective) if/when we present
4776 the stop to the user. */
4777 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4780 mark_ptid
= ecs
->ptid
;
4782 set_executing (mark_ptid
, 0);
4784 /* Likewise the resumed flag. */
4785 set_resumed (mark_ptid
, 0);
4788 switch (ecs
->ws
.kind
)
4790 case TARGET_WAITKIND_LOADED
:
4792 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4793 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4794 context_switch (ecs
->ptid
);
4795 /* Ignore gracefully during startup of the inferior, as it might
4796 be the shell which has just loaded some objects, otherwise
4797 add the symbols for the newly loaded objects. Also ignore at
4798 the beginning of an attach or remote session; we will query
4799 the full list of libraries once the connection is
4802 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4803 if (stop_soon
== NO_STOP_QUIETLY
)
4805 struct regcache
*regcache
;
4807 regcache
= get_thread_regcache (ecs
->ptid
);
4809 handle_solib_event ();
4811 ecs
->event_thread
->control
.stop_bpstat
4812 = bpstat_stop_status (get_regcache_aspace (regcache
),
4813 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4815 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4817 /* A catchpoint triggered. */
4818 process_event_stop_test (ecs
);
4822 /* If requested, stop when the dynamic linker notifies
4823 gdb of events. This allows the user to get control
4824 and place breakpoints in initializer routines for
4825 dynamically loaded objects (among other things). */
4826 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4827 if (stop_on_solib_events
)
4829 /* Make sure we print "Stopped due to solib-event" in
4831 stop_print_frame
= 1;
4838 /* If we are skipping through a shell, or through shared library
4839 loading that we aren't interested in, resume the program. If
4840 we're running the program normally, also resume. */
4841 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
4843 /* Loading of shared libraries might have changed breakpoint
4844 addresses. Make sure new breakpoints are inserted. */
4845 if (stop_soon
== NO_STOP_QUIETLY
)
4846 insert_breakpoints ();
4847 resume (GDB_SIGNAL_0
);
4848 prepare_to_wait (ecs
);
4852 /* But stop if we're attaching or setting up a remote
4854 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4855 || stop_soon
== STOP_QUIETLY_REMOTE
)
4858 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4863 internal_error (__FILE__
, __LINE__
,
4864 _("unhandled stop_soon: %d"), (int) stop_soon
);
4866 case TARGET_WAITKIND_SPURIOUS
:
4868 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
4869 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4870 context_switch (ecs
->ptid
);
4871 resume (GDB_SIGNAL_0
);
4872 prepare_to_wait (ecs
);
4875 case TARGET_WAITKIND_EXITED
:
4876 case TARGET_WAITKIND_SIGNALLED
:
4879 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4880 fprintf_unfiltered (gdb_stdlog
,
4881 "infrun: TARGET_WAITKIND_EXITED\n");
4883 fprintf_unfiltered (gdb_stdlog
,
4884 "infrun: TARGET_WAITKIND_SIGNALLED\n");
4887 inferior_ptid
= ecs
->ptid
;
4888 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
4889 set_current_program_space (current_inferior ()->pspace
);
4890 handle_vfork_child_exec_or_exit (0);
4891 target_terminal_ours (); /* Must do this before mourn anyway. */
4893 /* Clearing any previous state of convenience variables. */
4894 clear_exit_convenience_vars ();
4896 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4898 /* Record the exit code in the convenience variable $_exitcode, so
4899 that the user can inspect this again later. */
4900 set_internalvar_integer (lookup_internalvar ("_exitcode"),
4901 (LONGEST
) ecs
->ws
.value
.integer
);
4903 /* Also record this in the inferior itself. */
4904 current_inferior ()->has_exit_code
= 1;
4905 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
4907 /* Support the --return-child-result option. */
4908 return_child_result_value
= ecs
->ws
.value
.integer
;
4910 observer_notify_exited (ecs
->ws
.value
.integer
);
4914 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4915 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4917 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
4919 /* Set the value of the internal variable $_exitsignal,
4920 which holds the signal uncaught by the inferior. */
4921 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
4922 gdbarch_gdb_signal_to_target (gdbarch
,
4923 ecs
->ws
.value
.sig
));
4927 /* We don't have access to the target's method used for
4928 converting between signal numbers (GDB's internal
4929 representation <-> target's representation).
4930 Therefore, we cannot do a good job at displaying this
4931 information to the user. It's better to just warn
4932 her about it (if infrun debugging is enabled), and
4935 fprintf_filtered (gdb_stdlog
, _("\
4936 Cannot fill $_exitsignal with the correct signal number.\n"));
4939 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
4942 gdb_flush (gdb_stdout
);
4943 target_mourn_inferior ();
4944 stop_print_frame
= 0;
4948 /* The following are the only cases in which we keep going;
4949 the above cases end in a continue or goto. */
4950 case TARGET_WAITKIND_FORKED
:
4951 case TARGET_WAITKIND_VFORKED
:
4954 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4955 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
4957 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
4960 /* Check whether the inferior is displaced stepping. */
4962 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4963 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4965 /* If checking displaced stepping is supported, and thread
4966 ecs->ptid is displaced stepping. */
4967 if (displaced_step_in_progress_thread (ecs
->ptid
))
4969 struct inferior
*parent_inf
4970 = find_inferior_ptid (ecs
->ptid
);
4971 struct regcache
*child_regcache
;
4972 CORE_ADDR parent_pc
;
4974 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
4975 indicating that the displaced stepping of syscall instruction
4976 has been done. Perform cleanup for parent process here. Note
4977 that this operation also cleans up the child process for vfork,
4978 because their pages are shared. */
4979 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
4980 /* Start a new step-over in another thread if there's one
4984 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4986 struct displaced_step_inferior_state
*displaced
4987 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
4989 /* Restore scratch pad for child process. */
4990 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
4993 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
4994 the child's PC is also within the scratchpad. Set the child's PC
4995 to the parent's PC value, which has already been fixed up.
4996 FIXME: we use the parent's aspace here, although we're touching
4997 the child, because the child hasn't been added to the inferior
4998 list yet at this point. */
5001 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
5003 parent_inf
->aspace
);
5004 /* Read PC value of parent process. */
5005 parent_pc
= regcache_read_pc (regcache
);
5007 if (debug_displaced
)
5008 fprintf_unfiltered (gdb_stdlog
,
5009 "displaced: write child pc from %s to %s\n",
5011 regcache_read_pc (child_regcache
)),
5012 paddress (gdbarch
, parent_pc
));
5014 regcache_write_pc (child_regcache
, parent_pc
);
5018 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5019 context_switch (ecs
->ptid
);
5021 /* Immediately detach breakpoints from the child before there's
5022 any chance of letting the user delete breakpoints from the
5023 breakpoint lists. If we don't do this early, it's easy to
5024 leave left over traps in the child, vis: "break foo; catch
5025 fork; c; <fork>; del; c; <child calls foo>". We only follow
5026 the fork on the last `continue', and by that time the
5027 breakpoint at "foo" is long gone from the breakpoint table.
5028 If we vforked, then we don't need to unpatch here, since both
5029 parent and child are sharing the same memory pages; we'll
5030 need to unpatch at follow/detach time instead to be certain
5031 that new breakpoints added between catchpoint hit time and
5032 vfork follow are detached. */
5033 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5035 /* This won't actually modify the breakpoint list, but will
5036 physically remove the breakpoints from the child. */
5037 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5040 delete_just_stopped_threads_single_step_breakpoints ();
5042 /* In case the event is caught by a catchpoint, remember that
5043 the event is to be followed at the next resume of the thread,
5044 and not immediately. */
5045 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5047 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5049 ecs
->event_thread
->control
.stop_bpstat
5050 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5051 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5053 /* If no catchpoint triggered for this, then keep going. Note
5054 that we're interested in knowing the bpstat actually causes a
5055 stop, not just if it may explain the signal. Software
5056 watchpoints, for example, always appear in the bpstat. */
5057 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5063 = (follow_fork_mode_string
== follow_fork_mode_child
);
5065 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5067 should_resume
= follow_fork ();
5070 child
= ecs
->ws
.value
.related_pid
;
5072 /* In non-stop mode, also resume the other branch. */
5073 if (!detach_fork
&& (non_stop
5074 || (sched_multi
&& target_is_non_stop_p ())))
5077 switch_to_thread (parent
);
5079 switch_to_thread (child
);
5081 ecs
->event_thread
= inferior_thread ();
5082 ecs
->ptid
= inferior_ptid
;
5087 switch_to_thread (child
);
5089 switch_to_thread (parent
);
5091 ecs
->event_thread
= inferior_thread ();
5092 ecs
->ptid
= inferior_ptid
;
5100 process_event_stop_test (ecs
);
5103 case TARGET_WAITKIND_VFORK_DONE
:
5104 /* Done with the shared memory region. Re-insert breakpoints in
5105 the parent, and keep going. */
5108 fprintf_unfiltered (gdb_stdlog
,
5109 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5111 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5112 context_switch (ecs
->ptid
);
5114 current_inferior ()->waiting_for_vfork_done
= 0;
5115 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5116 /* This also takes care of reinserting breakpoints in the
5117 previously locked inferior. */
5121 case TARGET_WAITKIND_EXECD
:
5123 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5125 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5126 context_switch (ecs
->ptid
);
5128 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5130 /* Do whatever is necessary to the parent branch of the vfork. */
5131 handle_vfork_child_exec_or_exit (1);
5133 /* This causes the eventpoints and symbol table to be reset.
5134 Must do this now, before trying to determine whether to
5136 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5138 /* In follow_exec we may have deleted the original thread and
5139 created a new one. Make sure that the event thread is the
5140 execd thread for that case (this is a nop otherwise). */
5141 ecs
->event_thread
= inferior_thread ();
5143 ecs
->event_thread
->control
.stop_bpstat
5144 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5145 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5147 /* Note that this may be referenced from inside
5148 bpstat_stop_status above, through inferior_has_execd. */
5149 xfree (ecs
->ws
.value
.execd_pathname
);
5150 ecs
->ws
.value
.execd_pathname
= NULL
;
5152 /* If no catchpoint triggered for this, then keep going. */
5153 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5155 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5159 process_event_stop_test (ecs
);
5162 /* Be careful not to try to gather much state about a thread
5163 that's in a syscall. It's frequently a losing proposition. */
5164 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5166 fprintf_unfiltered (gdb_stdlog
,
5167 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5168 /* Getting the current syscall number. */
5169 if (handle_syscall_event (ecs
) == 0)
5170 process_event_stop_test (ecs
);
5173 /* Before examining the threads further, step this thread to
5174 get it entirely out of the syscall. (We get notice of the
5175 event when the thread is just on the verge of exiting a
5176 syscall. Stepping one instruction seems to get it back
5178 case TARGET_WAITKIND_SYSCALL_RETURN
:
5180 fprintf_unfiltered (gdb_stdlog
,
5181 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5182 if (handle_syscall_event (ecs
) == 0)
5183 process_event_stop_test (ecs
);
5186 case TARGET_WAITKIND_STOPPED
:
5188 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5189 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5190 handle_signal_stop (ecs
);
5193 case TARGET_WAITKIND_NO_HISTORY
:
5195 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5196 /* Reverse execution: target ran out of history info. */
5198 /* Switch to the stopped thread. */
5199 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5200 context_switch (ecs
->ptid
);
5202 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5204 delete_just_stopped_threads_single_step_breakpoints ();
5205 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5206 observer_notify_no_history ();
5212 /* A wrapper around handle_inferior_event_1, which also makes sure
5213 that all temporary struct value objects that were created during
5214 the handling of the event get deleted at the end. */
5217 handle_inferior_event (struct execution_control_state
*ecs
)
5219 struct value
*mark
= value_mark ();
5221 handle_inferior_event_1 (ecs
);
5222 /* Purge all temporary values created during the event handling,
5223 as it could be a long time before we return to the command level
5224 where such values would otherwise be purged. */
5225 value_free_to_mark (mark
);
5228 /* Restart threads back to what they were trying to do back when we
5229 paused them for an in-line step-over. The EVENT_THREAD thread is
5233 restart_threads (struct thread_info
*event_thread
)
5235 struct thread_info
*tp
;
5236 struct thread_info
*step_over
= NULL
;
5238 /* In case the instruction just stepped spawned a new thread. */
5239 update_thread_list ();
5241 ALL_NON_EXITED_THREADS (tp
)
5243 if (tp
== event_thread
)
5246 fprintf_unfiltered (gdb_stdlog
,
5247 "infrun: restart threads: "
5248 "[%s] is event thread\n",
5249 target_pid_to_str (tp
->ptid
));
5253 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5256 fprintf_unfiltered (gdb_stdlog
,
5257 "infrun: restart threads: "
5258 "[%s] not meant to be running\n",
5259 target_pid_to_str (tp
->ptid
));
5266 fprintf_unfiltered (gdb_stdlog
,
5267 "infrun: restart threads: [%s] resumed\n",
5268 target_pid_to_str (tp
->ptid
));
5269 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5273 if (thread_is_in_step_over_chain (tp
))
5276 fprintf_unfiltered (gdb_stdlog
,
5277 "infrun: restart threads: "
5278 "[%s] needs step-over\n",
5279 target_pid_to_str (tp
->ptid
));
5280 gdb_assert (!tp
->resumed
);
5285 if (tp
->suspend
.waitstatus_pending_p
)
5288 fprintf_unfiltered (gdb_stdlog
,
5289 "infrun: restart threads: "
5290 "[%s] has pending status\n",
5291 target_pid_to_str (tp
->ptid
));
5296 /* If some thread needs to start a step-over at this point, it
5297 should still be in the step-over queue, and thus skipped
5299 if (thread_still_needs_step_over (tp
))
5301 internal_error (__FILE__
, __LINE__
,
5302 "thread [%s] needs a step-over, but not in "
5303 "step-over queue\n",
5304 target_pid_to_str (tp
->ptid
));
5307 if (currently_stepping (tp
))
5310 fprintf_unfiltered (gdb_stdlog
,
5311 "infrun: restart threads: [%s] was stepping\n",
5312 target_pid_to_str (tp
->ptid
));
5313 keep_going_stepped_thread (tp
);
5317 struct execution_control_state ecss
;
5318 struct execution_control_state
*ecs
= &ecss
;
5321 fprintf_unfiltered (gdb_stdlog
,
5322 "infrun: restart threads: [%s] continuing\n",
5323 target_pid_to_str (tp
->ptid
));
5324 reset_ecs (ecs
, tp
);
5325 switch_to_thread (tp
->ptid
);
5326 keep_going_pass_signal (ecs
);
5331 /* Callback for iterate_over_threads. Find a resumed thread that has
5332 a pending waitstatus. */
5335 resumed_thread_with_pending_status (struct thread_info
*tp
,
5339 && tp
->suspend
.waitstatus_pending_p
);
5342 /* Called when we get an event that may finish an in-line or
5343 out-of-line (displaced stepping) step-over started previously.
5344 Return true if the event is processed and we should go back to the
5345 event loop; false if the caller should continue processing the
5349 finish_step_over (struct execution_control_state
*ecs
)
5351 int had_step_over_info
;
5353 displaced_step_fixup (ecs
->ptid
,
5354 ecs
->event_thread
->suspend
.stop_signal
);
5356 had_step_over_info
= step_over_info_valid_p ();
5358 if (had_step_over_info
)
5360 /* If we're stepping over a breakpoint with all threads locked,
5361 then only the thread that was stepped should be reporting
5363 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5365 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5366 clear_step_over_info ();
5369 if (!target_is_non_stop_p ())
5372 /* Start a new step-over in another thread if there's one that
5376 /* If we were stepping over a breakpoint before, and haven't started
5377 a new in-line step-over sequence, then restart all other threads
5378 (except the event thread). We can't do this in all-stop, as then
5379 e.g., we wouldn't be able to issue any other remote packet until
5380 these other threads stop. */
5381 if (had_step_over_info
&& !step_over_info_valid_p ())
5383 struct thread_info
*pending
;
5385 /* If we only have threads with pending statuses, the restart
5386 below won't restart any thread and so nothing re-inserts the
5387 breakpoint we just stepped over. But we need it inserted
5388 when we later process the pending events, otherwise if
5389 another thread has a pending event for this breakpoint too,
5390 we'd discard its event (because the breakpoint that
5391 originally caused the event was no longer inserted). */
5392 context_switch (ecs
->ptid
);
5393 insert_breakpoints ();
5395 restart_threads (ecs
->event_thread
);
5397 /* If we have events pending, go through handle_inferior_event
5398 again, picking up a pending event at random. This avoids
5399 thread starvation. */
5401 /* But not if we just stepped over a watchpoint in order to let
5402 the instruction execute so we can evaluate its expression.
5403 The set of watchpoints that triggered is recorded in the
5404 breakpoint objects themselves (see bp->watchpoint_triggered).
5405 If we processed another event first, that other event could
5406 clobber this info. */
5407 if (ecs
->event_thread
->stepping_over_watchpoint
)
5410 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5412 if (pending
!= NULL
)
5414 struct thread_info
*tp
= ecs
->event_thread
;
5415 struct regcache
*regcache
;
5419 fprintf_unfiltered (gdb_stdlog
,
5420 "infrun: found resumed threads with "
5421 "pending events, saving status\n");
5424 gdb_assert (pending
!= tp
);
5426 /* Record the event thread's event for later. */
5427 save_waitstatus (tp
, &ecs
->ws
);
5428 /* This was cleared early, by handle_inferior_event. Set it
5429 so this pending event is considered by
5433 gdb_assert (!tp
->executing
);
5435 regcache
= get_thread_regcache (tp
->ptid
);
5436 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5440 fprintf_unfiltered (gdb_stdlog
,
5441 "infrun: saved stop_pc=%s for %s "
5442 "(currently_stepping=%d)\n",
5443 paddress (target_gdbarch (),
5444 tp
->suspend
.stop_pc
),
5445 target_pid_to_str (tp
->ptid
),
5446 currently_stepping (tp
));
5449 /* This in-line step-over finished; clear this so we won't
5450 start a new one. This is what handle_signal_stop would
5451 do, if we returned false. */
5452 tp
->stepping_over_breakpoint
= 0;
5454 /* Wake up the event loop again. */
5455 mark_async_event_handler (infrun_async_inferior_event_token
);
5457 prepare_to_wait (ecs
);
5465 /* Come here when the program has stopped with a signal. */
5468 handle_signal_stop (struct execution_control_state
*ecs
)
5470 struct frame_info
*frame
;
5471 struct gdbarch
*gdbarch
;
5472 int stopped_by_watchpoint
;
5473 enum stop_kind stop_soon
;
5476 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5478 /* Do we need to clean up the state of a thread that has
5479 completed a displaced single-step? (Doing so usually affects
5480 the PC, so do it here, before we set stop_pc.) */
5481 if (finish_step_over (ecs
))
5484 /* If we either finished a single-step or hit a breakpoint, but
5485 the user wanted this thread to be stopped, pretend we got a
5486 SIG0 (generic unsignaled stop). */
5487 if (ecs
->event_thread
->stop_requested
5488 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5489 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5491 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5495 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5496 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5497 struct cleanup
*old_chain
= save_inferior_ptid ();
5499 inferior_ptid
= ecs
->ptid
;
5501 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5502 paddress (gdbarch
, stop_pc
));
5503 if (target_stopped_by_watchpoint ())
5507 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5509 if (target_stopped_data_address (¤t_target
, &addr
))
5510 fprintf_unfiltered (gdb_stdlog
,
5511 "infrun: stopped data address = %s\n",
5512 paddress (gdbarch
, addr
));
5514 fprintf_unfiltered (gdb_stdlog
,
5515 "infrun: (no data address available)\n");
5518 do_cleanups (old_chain
);
5521 /* This is originated from start_remote(), start_inferior() and
5522 shared libraries hook functions. */
5523 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5524 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5526 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5527 context_switch (ecs
->ptid
);
5529 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5530 stop_print_frame
= 1;
5535 /* This originates from attach_command(). We need to overwrite
5536 the stop_signal here, because some kernels don't ignore a
5537 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5538 See more comments in inferior.h. On the other hand, if we
5539 get a non-SIGSTOP, report it to the user - assume the backend
5540 will handle the SIGSTOP if it should show up later.
5542 Also consider that the attach is complete when we see a
5543 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5544 target extended-remote report it instead of a SIGSTOP
5545 (e.g. gdbserver). We already rely on SIGTRAP being our
5546 signal, so this is no exception.
5548 Also consider that the attach is complete when we see a
5549 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5550 the target to stop all threads of the inferior, in case the
5551 low level attach operation doesn't stop them implicitly. If
5552 they weren't stopped implicitly, then the stub will report a
5553 GDB_SIGNAL_0, meaning: stopped for no particular reason
5554 other than GDB's request. */
5555 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5556 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5557 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5558 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5560 stop_print_frame
= 1;
5562 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5566 /* See if something interesting happened to the non-current thread. If
5567 so, then switch to that thread. */
5568 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5571 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5573 context_switch (ecs
->ptid
);
5575 if (deprecated_context_hook
)
5576 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
5579 /* At this point, get hold of the now-current thread's frame. */
5580 frame
= get_current_frame ();
5581 gdbarch
= get_frame_arch (frame
);
5583 /* Pull the single step breakpoints out of the target. */
5584 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5586 struct regcache
*regcache
;
5587 struct address_space
*aspace
;
5590 regcache
= get_thread_regcache (ecs
->ptid
);
5591 aspace
= get_regcache_aspace (regcache
);
5592 pc
= regcache_read_pc (regcache
);
5594 /* However, before doing so, if this single-step breakpoint was
5595 actually for another thread, set this thread up for moving
5597 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5600 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5604 fprintf_unfiltered (gdb_stdlog
,
5605 "infrun: [%s] hit another thread's "
5606 "single-step breakpoint\n",
5607 target_pid_to_str (ecs
->ptid
));
5609 ecs
->hit_singlestep_breakpoint
= 1;
5616 fprintf_unfiltered (gdb_stdlog
,
5617 "infrun: [%s] hit its "
5618 "single-step breakpoint\n",
5619 target_pid_to_str (ecs
->ptid
));
5623 delete_just_stopped_threads_single_step_breakpoints ();
5625 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5626 && ecs
->event_thread
->control
.trap_expected
5627 && ecs
->event_thread
->stepping_over_watchpoint
)
5628 stopped_by_watchpoint
= 0;
5630 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5632 /* If necessary, step over this watchpoint. We'll be back to display
5634 if (stopped_by_watchpoint
5635 && (target_have_steppable_watchpoint
5636 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5638 /* At this point, we are stopped at an instruction which has
5639 attempted to write to a piece of memory under control of
5640 a watchpoint. The instruction hasn't actually executed
5641 yet. If we were to evaluate the watchpoint expression
5642 now, we would get the old value, and therefore no change
5643 would seem to have occurred.
5645 In order to make watchpoints work `right', we really need
5646 to complete the memory write, and then evaluate the
5647 watchpoint expression. We do this by single-stepping the
5650 It may not be necessary to disable the watchpoint to step over
5651 it. For example, the PA can (with some kernel cooperation)
5652 single step over a watchpoint without disabling the watchpoint.
5654 It is far more common to need to disable a watchpoint to step
5655 the inferior over it. If we have non-steppable watchpoints,
5656 we must disable the current watchpoint; it's simplest to
5657 disable all watchpoints.
5659 Any breakpoint at PC must also be stepped over -- if there's
5660 one, it will have already triggered before the watchpoint
5661 triggered, and we either already reported it to the user, or
5662 it didn't cause a stop and we called keep_going. In either
5663 case, if there was a breakpoint at PC, we must be trying to
5665 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5670 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5671 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5672 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5673 ecs
->event_thread
->control
.stop_step
= 0;
5674 stop_print_frame
= 1;
5675 stopped_by_random_signal
= 0;
5677 /* Hide inlined functions starting here, unless we just performed stepi or
5678 nexti. After stepi and nexti, always show the innermost frame (not any
5679 inline function call sites). */
5680 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5682 struct address_space
*aspace
=
5683 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5685 /* skip_inline_frames is expensive, so we avoid it if we can
5686 determine that the address is one where functions cannot have
5687 been inlined. This improves performance with inferiors that
5688 load a lot of shared libraries, because the solib event
5689 breakpoint is defined as the address of a function (i.e. not
5690 inline). Note that we have to check the previous PC as well
5691 as the current one to catch cases when we have just
5692 single-stepped off a breakpoint prior to reinstating it.
5693 Note that we're assuming that the code we single-step to is
5694 not inline, but that's not definitive: there's nothing
5695 preventing the event breakpoint function from containing
5696 inlined code, and the single-step ending up there. If the
5697 user had set a breakpoint on that inlined code, the missing
5698 skip_inline_frames call would break things. Fortunately
5699 that's an extremely unlikely scenario. */
5700 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5701 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5702 && ecs
->event_thread
->control
.trap_expected
5703 && pc_at_non_inline_function (aspace
,
5704 ecs
->event_thread
->prev_pc
,
5707 skip_inline_frames (ecs
->ptid
);
5709 /* Re-fetch current thread's frame in case that invalidated
5711 frame
= get_current_frame ();
5712 gdbarch
= get_frame_arch (frame
);
5716 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5717 && ecs
->event_thread
->control
.trap_expected
5718 && gdbarch_single_step_through_delay_p (gdbarch
)
5719 && currently_stepping (ecs
->event_thread
))
5721 /* We're trying to step off a breakpoint. Turns out that we're
5722 also on an instruction that needs to be stepped multiple
5723 times before it's been fully executing. E.g., architectures
5724 with a delay slot. It needs to be stepped twice, once for
5725 the instruction and once for the delay slot. */
5726 int step_through_delay
5727 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5729 if (debug_infrun
&& step_through_delay
)
5730 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5731 if (ecs
->event_thread
->control
.step_range_end
== 0
5732 && step_through_delay
)
5734 /* The user issued a continue when stopped at a breakpoint.
5735 Set up for another trap and get out of here. */
5736 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5740 else if (step_through_delay
)
5742 /* The user issued a step when stopped at a breakpoint.
5743 Maybe we should stop, maybe we should not - the delay
5744 slot *might* correspond to a line of source. In any
5745 case, don't decide that here, just set
5746 ecs->stepping_over_breakpoint, making sure we
5747 single-step again before breakpoints are re-inserted. */
5748 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5752 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5753 handles this event. */
5754 ecs
->event_thread
->control
.stop_bpstat
5755 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5756 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5758 /* Following in case break condition called a
5760 stop_print_frame
= 1;
5762 /* This is where we handle "moribund" watchpoints. Unlike
5763 software breakpoints traps, hardware watchpoint traps are
5764 always distinguishable from random traps. If no high-level
5765 watchpoint is associated with the reported stop data address
5766 anymore, then the bpstat does not explain the signal ---
5767 simply make sure to ignore it if `stopped_by_watchpoint' is
5771 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5772 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5774 && stopped_by_watchpoint
)
5775 fprintf_unfiltered (gdb_stdlog
,
5776 "infrun: no user watchpoint explains "
5777 "watchpoint SIGTRAP, ignoring\n");
5779 /* NOTE: cagney/2003-03-29: These checks for a random signal
5780 at one stage in the past included checks for an inferior
5781 function call's call dummy's return breakpoint. The original
5782 comment, that went with the test, read:
5784 ``End of a stack dummy. Some systems (e.g. Sony news) give
5785 another signal besides SIGTRAP, so check here as well as
5788 If someone ever tries to get call dummys on a
5789 non-executable stack to work (where the target would stop
5790 with something like a SIGSEGV), then those tests might need
5791 to be re-instated. Given, however, that the tests were only
5792 enabled when momentary breakpoints were not being used, I
5793 suspect that it won't be the case.
5795 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5796 be necessary for call dummies on a non-executable stack on
5799 /* See if the breakpoints module can explain the signal. */
5801 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5802 ecs
->event_thread
->suspend
.stop_signal
);
5804 /* Maybe this was a trap for a software breakpoint that has since
5806 if (random_signal
&& target_stopped_by_sw_breakpoint ())
5808 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
5810 struct regcache
*regcache
;
5813 /* Re-adjust PC to what the program would see if GDB was not
5815 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
5816 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
5819 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
5821 if (record_full_is_used ())
5822 record_full_gdb_operation_disable_set ();
5824 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
5826 do_cleanups (old_cleanups
);
5831 /* A delayed software breakpoint event. Ignore the trap. */
5833 fprintf_unfiltered (gdb_stdlog
,
5834 "infrun: delayed software breakpoint "
5835 "trap, ignoring\n");
5840 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
5841 has since been removed. */
5842 if (random_signal
&& target_stopped_by_hw_breakpoint ())
5844 /* A delayed hardware breakpoint event. Ignore the trap. */
5846 fprintf_unfiltered (gdb_stdlog
,
5847 "infrun: delayed hardware breakpoint/watchpoint "
5848 "trap, ignoring\n");
5852 /* If not, perhaps stepping/nexting can. */
5854 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5855 && currently_stepping (ecs
->event_thread
));
5857 /* Perhaps the thread hit a single-step breakpoint of _another_
5858 thread. Single-step breakpoints are transparent to the
5859 breakpoints module. */
5861 random_signal
= !ecs
->hit_singlestep_breakpoint
;
5863 /* No? Perhaps we got a moribund watchpoint. */
5865 random_signal
= !stopped_by_watchpoint
;
5867 /* For the program's own signals, act according to
5868 the signal handling tables. */
5872 /* Signal not for debugging purposes. */
5873 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
5874 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
5877 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
5878 gdb_signal_to_symbol_string (stop_signal
));
5880 stopped_by_random_signal
= 1;
5882 /* Always stop on signals if we're either just gaining control
5883 of the program, or the user explicitly requested this thread
5884 to remain stopped. */
5885 if (stop_soon
!= NO_STOP_QUIETLY
5886 || ecs
->event_thread
->stop_requested
5888 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
5894 /* Notify observers the signal has "handle print" set. Note we
5895 returned early above if stopping; normal_stop handles the
5896 printing in that case. */
5897 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
5899 /* The signal table tells us to print about this signal. */
5900 target_terminal_ours_for_output ();
5901 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
5902 target_terminal_inferior ();
5905 /* Clear the signal if it should not be passed. */
5906 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
5907 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5909 if (ecs
->event_thread
->prev_pc
== stop_pc
5910 && ecs
->event_thread
->control
.trap_expected
5911 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5915 /* We were just starting a new sequence, attempting to
5916 single-step off of a breakpoint and expecting a SIGTRAP.
5917 Instead this signal arrives. This signal will take us out
5918 of the stepping range so GDB needs to remember to, when
5919 the signal handler returns, resume stepping off that
5921 /* To simplify things, "continue" is forced to use the same
5922 code paths as single-step - set a breakpoint at the
5923 signal return address and then, once hit, step off that
5926 fprintf_unfiltered (gdb_stdlog
,
5927 "infrun: signal arrived while stepping over "
5930 was_in_line
= step_over_info_valid_p ();
5931 clear_step_over_info ();
5932 insert_hp_step_resume_breakpoint_at_frame (frame
);
5933 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5934 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5935 ecs
->event_thread
->control
.trap_expected
= 0;
5937 if (target_is_non_stop_p ())
5939 /* Either "set non-stop" is "on", or the target is
5940 always in non-stop mode. In this case, we have a bit
5941 more work to do. Resume the current thread, and if
5942 we had paused all threads, restart them while the
5943 signal handler runs. */
5948 restart_threads (ecs
->event_thread
);
5950 else if (debug_infrun
)
5952 fprintf_unfiltered (gdb_stdlog
,
5953 "infrun: no need to restart threads\n");
5958 /* If we were nexting/stepping some other thread, switch to
5959 it, so that we don't continue it, losing control. */
5960 if (!switch_back_to_stepped_thread (ecs
))
5965 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
5966 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
5967 || ecs
->event_thread
->control
.step_range_end
== 1)
5968 && frame_id_eq (get_stack_frame_id (frame
),
5969 ecs
->event_thread
->control
.step_stack_frame_id
)
5970 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5972 /* The inferior is about to take a signal that will take it
5973 out of the single step range. Set a breakpoint at the
5974 current PC (which is presumably where the signal handler
5975 will eventually return) and then allow the inferior to
5978 Note that this is only needed for a signal delivered
5979 while in the single-step range. Nested signals aren't a
5980 problem as they eventually all return. */
5982 fprintf_unfiltered (gdb_stdlog
,
5983 "infrun: signal may take us out of "
5984 "single-step range\n");
5986 clear_step_over_info ();
5987 insert_hp_step_resume_breakpoint_at_frame (frame
);
5988 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5989 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5990 ecs
->event_thread
->control
.trap_expected
= 0;
5995 /* Note: step_resume_breakpoint may be non-NULL. This occures
5996 when either there's a nested signal, or when there's a
5997 pending signal enabled just as the signal handler returns
5998 (leaving the inferior at the step-resume-breakpoint without
5999 actually executing it). Either way continue until the
6000 breakpoint is really hit. */
6002 if (!switch_back_to_stepped_thread (ecs
))
6005 fprintf_unfiltered (gdb_stdlog
,
6006 "infrun: random signal, keep going\n");
6013 process_event_stop_test (ecs
);
6016 /* Come here when we've got some debug event / signal we can explain
6017 (IOW, not a random signal), and test whether it should cause a
6018 stop, or whether we should resume the inferior (transparently).
6019 E.g., could be a breakpoint whose condition evaluates false; we
6020 could be still stepping within the line; etc. */
6023 process_event_stop_test (struct execution_control_state
*ecs
)
6025 struct symtab_and_line stop_pc_sal
;
6026 struct frame_info
*frame
;
6027 struct gdbarch
*gdbarch
;
6028 CORE_ADDR jmp_buf_pc
;
6029 struct bpstat_what what
;
6031 /* Handle cases caused by hitting a breakpoint. */
6033 frame
= get_current_frame ();
6034 gdbarch
= get_frame_arch (frame
);
6036 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6038 if (what
.call_dummy
)
6040 stop_stack_dummy
= what
.call_dummy
;
6043 /* A few breakpoint types have callbacks associated (e.g.,
6044 bp_jit_event). Run them now. */
6045 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6047 /* If we hit an internal event that triggers symbol changes, the
6048 current frame will be invalidated within bpstat_what (e.g., if we
6049 hit an internal solib event). Re-fetch it. */
6050 frame
= get_current_frame ();
6051 gdbarch
= get_frame_arch (frame
);
6053 switch (what
.main_action
)
6055 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6056 /* If we hit the breakpoint at longjmp while stepping, we
6057 install a momentary breakpoint at the target of the
6061 fprintf_unfiltered (gdb_stdlog
,
6062 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6064 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6066 if (what
.is_longjmp
)
6068 struct value
*arg_value
;
6070 /* If we set the longjmp breakpoint via a SystemTap probe,
6071 then use it to extract the arguments. The destination PC
6072 is the third argument to the probe. */
6073 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6076 jmp_buf_pc
= value_as_address (arg_value
);
6077 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6079 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6080 || !gdbarch_get_longjmp_target (gdbarch
,
6081 frame
, &jmp_buf_pc
))
6084 fprintf_unfiltered (gdb_stdlog
,
6085 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6086 "(!gdbarch_get_longjmp_target)\n");
6091 /* Insert a breakpoint at resume address. */
6092 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6095 check_exception_resume (ecs
, frame
);
6099 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6101 struct frame_info
*init_frame
;
6103 /* There are several cases to consider.
6105 1. The initiating frame no longer exists. In this case we
6106 must stop, because the exception or longjmp has gone too
6109 2. The initiating frame exists, and is the same as the
6110 current frame. We stop, because the exception or longjmp
6113 3. The initiating frame exists and is different from the
6114 current frame. This means the exception or longjmp has
6115 been caught beneath the initiating frame, so keep going.
6117 4. longjmp breakpoint has been placed just to protect
6118 against stale dummy frames and user is not interested in
6119 stopping around longjmps. */
6122 fprintf_unfiltered (gdb_stdlog
,
6123 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6125 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6127 delete_exception_resume_breakpoint (ecs
->event_thread
);
6129 if (what
.is_longjmp
)
6131 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6133 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6141 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6145 struct frame_id current_id
6146 = get_frame_id (get_current_frame ());
6147 if (frame_id_eq (current_id
,
6148 ecs
->event_thread
->initiating_frame
))
6150 /* Case 2. Fall through. */
6160 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6162 delete_step_resume_breakpoint (ecs
->event_thread
);
6164 end_stepping_range (ecs
);
6168 case BPSTAT_WHAT_SINGLE
:
6170 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6171 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6172 /* Still need to check other stuff, at least the case where we
6173 are stepping and step out of the right range. */
6176 case BPSTAT_WHAT_STEP_RESUME
:
6178 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6180 delete_step_resume_breakpoint (ecs
->event_thread
);
6181 if (ecs
->event_thread
->control
.proceed_to_finish
6182 && execution_direction
== EXEC_REVERSE
)
6184 struct thread_info
*tp
= ecs
->event_thread
;
6186 /* We are finishing a function in reverse, and just hit the
6187 step-resume breakpoint at the start address of the
6188 function, and we're almost there -- just need to back up
6189 by one more single-step, which should take us back to the
6191 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6195 fill_in_stop_func (gdbarch
, ecs
);
6196 if (stop_pc
== ecs
->stop_func_start
6197 && execution_direction
== EXEC_REVERSE
)
6199 /* We are stepping over a function call in reverse, and just
6200 hit the step-resume breakpoint at the start address of
6201 the function. Go back to single-stepping, which should
6202 take us back to the function call. */
6203 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6209 case BPSTAT_WHAT_STOP_NOISY
:
6211 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6212 stop_print_frame
= 1;
6214 /* Assume the thread stopped for a breapoint. We'll still check
6215 whether a/the breakpoint is there when the thread is next
6217 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6222 case BPSTAT_WHAT_STOP_SILENT
:
6224 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6225 stop_print_frame
= 0;
6227 /* Assume the thread stopped for a breapoint. We'll still check
6228 whether a/the breakpoint is there when the thread is next
6230 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6234 case BPSTAT_WHAT_HP_STEP_RESUME
:
6236 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6238 delete_step_resume_breakpoint (ecs
->event_thread
);
6239 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6241 /* Back when the step-resume breakpoint was inserted, we
6242 were trying to single-step off a breakpoint. Go back to
6244 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6245 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6251 case BPSTAT_WHAT_KEEP_CHECKING
:
6255 /* If we stepped a permanent breakpoint and we had a high priority
6256 step-resume breakpoint for the address we stepped, but we didn't
6257 hit it, then we must have stepped into the signal handler. The
6258 step-resume was only necessary to catch the case of _not_
6259 stepping into the handler, so delete it, and fall through to
6260 checking whether the step finished. */
6261 if (ecs
->event_thread
->stepped_breakpoint
)
6263 struct breakpoint
*sr_bp
6264 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6267 && sr_bp
->loc
->permanent
6268 && sr_bp
->type
== bp_hp_step_resume
6269 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6272 fprintf_unfiltered (gdb_stdlog
,
6273 "infrun: stepped permanent breakpoint, stopped in "
6275 delete_step_resume_breakpoint (ecs
->event_thread
);
6276 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6280 /* We come here if we hit a breakpoint but should not stop for it.
6281 Possibly we also were stepping and should stop for that. So fall
6282 through and test for stepping. But, if not stepping, do not
6285 /* In all-stop mode, if we're currently stepping but have stopped in
6286 some other thread, we need to switch back to the stepped thread. */
6287 if (switch_back_to_stepped_thread (ecs
))
6290 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6293 fprintf_unfiltered (gdb_stdlog
,
6294 "infrun: step-resume breakpoint is inserted\n");
6296 /* Having a step-resume breakpoint overrides anything
6297 else having to do with stepping commands until
6298 that breakpoint is reached. */
6303 if (ecs
->event_thread
->control
.step_range_end
== 0)
6306 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6307 /* Likewise if we aren't even stepping. */
6312 /* Re-fetch current thread's frame in case the code above caused
6313 the frame cache to be re-initialized, making our FRAME variable
6314 a dangling pointer. */
6315 frame
= get_current_frame ();
6316 gdbarch
= get_frame_arch (frame
);
6317 fill_in_stop_func (gdbarch
, ecs
);
6319 /* If stepping through a line, keep going if still within it.
6321 Note that step_range_end is the address of the first instruction
6322 beyond the step range, and NOT the address of the last instruction
6325 Note also that during reverse execution, we may be stepping
6326 through a function epilogue and therefore must detect when
6327 the current-frame changes in the middle of a line. */
6329 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6330 && (execution_direction
!= EXEC_REVERSE
6331 || frame_id_eq (get_frame_id (frame
),
6332 ecs
->event_thread
->control
.step_frame_id
)))
6336 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6337 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6338 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6340 /* Tentatively re-enable range stepping; `resume' disables it if
6341 necessary (e.g., if we're stepping over a breakpoint or we
6342 have software watchpoints). */
6343 ecs
->event_thread
->control
.may_range_step
= 1;
6345 /* When stepping backward, stop at beginning of line range
6346 (unless it's the function entry point, in which case
6347 keep going back to the call point). */
6348 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6349 && stop_pc
!= ecs
->stop_func_start
6350 && execution_direction
== EXEC_REVERSE
)
6351 end_stepping_range (ecs
);
6358 /* We stepped out of the stepping range. */
6360 /* If we are stepping at the source level and entered the runtime
6361 loader dynamic symbol resolution code...
6363 EXEC_FORWARD: we keep on single stepping until we exit the run
6364 time loader code and reach the callee's address.
6366 EXEC_REVERSE: we've already executed the callee (backward), and
6367 the runtime loader code is handled just like any other
6368 undebuggable function call. Now we need only keep stepping
6369 backward through the trampoline code, and that's handled further
6370 down, so there is nothing for us to do here. */
6372 if (execution_direction
!= EXEC_REVERSE
6373 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6374 && in_solib_dynsym_resolve_code (stop_pc
))
6376 CORE_ADDR pc_after_resolver
=
6377 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6380 fprintf_unfiltered (gdb_stdlog
,
6381 "infrun: stepped into dynsym resolve code\n");
6383 if (pc_after_resolver
)
6385 /* Set up a step-resume breakpoint at the address
6386 indicated by SKIP_SOLIB_RESOLVER. */
6387 struct symtab_and_line sr_sal
;
6390 sr_sal
.pc
= pc_after_resolver
;
6391 sr_sal
.pspace
= get_frame_program_space (frame
);
6393 insert_step_resume_breakpoint_at_sal (gdbarch
,
6394 sr_sal
, null_frame_id
);
6401 if (ecs
->event_thread
->control
.step_range_end
!= 1
6402 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6403 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6404 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6407 fprintf_unfiltered (gdb_stdlog
,
6408 "infrun: stepped into signal trampoline\n");
6409 /* The inferior, while doing a "step" or "next", has ended up in
6410 a signal trampoline (either by a signal being delivered or by
6411 the signal handler returning). Just single-step until the
6412 inferior leaves the trampoline (either by calling the handler
6418 /* If we're in the return path from a shared library trampoline,
6419 we want to proceed through the trampoline when stepping. */
6420 /* macro/2012-04-25: This needs to come before the subroutine
6421 call check below as on some targets return trampolines look
6422 like subroutine calls (MIPS16 return thunks). */
6423 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6424 stop_pc
, ecs
->stop_func_name
)
6425 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6427 /* Determine where this trampoline returns. */
6428 CORE_ADDR real_stop_pc
;
6430 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6433 fprintf_unfiltered (gdb_stdlog
,
6434 "infrun: stepped into solib return tramp\n");
6436 /* Only proceed through if we know where it's going. */
6439 /* And put the step-breakpoint there and go until there. */
6440 struct symtab_and_line sr_sal
;
6442 init_sal (&sr_sal
); /* initialize to zeroes */
6443 sr_sal
.pc
= real_stop_pc
;
6444 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6445 sr_sal
.pspace
= get_frame_program_space (frame
);
6447 /* Do not specify what the fp should be when we stop since
6448 on some machines the prologue is where the new fp value
6450 insert_step_resume_breakpoint_at_sal (gdbarch
,
6451 sr_sal
, null_frame_id
);
6453 /* Restart without fiddling with the step ranges or
6460 /* Check for subroutine calls. The check for the current frame
6461 equalling the step ID is not necessary - the check of the
6462 previous frame's ID is sufficient - but it is a common case and
6463 cheaper than checking the previous frame's ID.
6465 NOTE: frame_id_eq will never report two invalid frame IDs as
6466 being equal, so to get into this block, both the current and
6467 previous frame must have valid frame IDs. */
6468 /* The outer_frame_id check is a heuristic to detect stepping
6469 through startup code. If we step over an instruction which
6470 sets the stack pointer from an invalid value to a valid value,
6471 we may detect that as a subroutine call from the mythical
6472 "outermost" function. This could be fixed by marking
6473 outermost frames as !stack_p,code_p,special_p. Then the
6474 initial outermost frame, before sp was valid, would
6475 have code_addr == &_start. See the comment in frame_id_eq
6477 if (!frame_id_eq (get_stack_frame_id (frame
),
6478 ecs
->event_thread
->control
.step_stack_frame_id
)
6479 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6480 ecs
->event_thread
->control
.step_stack_frame_id
)
6481 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6483 || (ecs
->event_thread
->control
.step_start_function
6484 != find_pc_function (stop_pc
)))))
6486 CORE_ADDR real_stop_pc
;
6489 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6491 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6493 /* I presume that step_over_calls is only 0 when we're
6494 supposed to be stepping at the assembly language level
6495 ("stepi"). Just stop. */
6496 /* And this works the same backward as frontward. MVS */
6497 end_stepping_range (ecs
);
6501 /* Reverse stepping through solib trampolines. */
6503 if (execution_direction
== EXEC_REVERSE
6504 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6505 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6506 || (ecs
->stop_func_start
== 0
6507 && in_solib_dynsym_resolve_code (stop_pc
))))
6509 /* Any solib trampoline code can be handled in reverse
6510 by simply continuing to single-step. We have already
6511 executed the solib function (backwards), and a few
6512 steps will take us back through the trampoline to the
6518 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6520 /* We're doing a "next".
6522 Normal (forward) execution: set a breakpoint at the
6523 callee's return address (the address at which the caller
6526 Reverse (backward) execution. set the step-resume
6527 breakpoint at the start of the function that we just
6528 stepped into (backwards), and continue to there. When we
6529 get there, we'll need to single-step back to the caller. */
6531 if (execution_direction
== EXEC_REVERSE
)
6533 /* If we're already at the start of the function, we've either
6534 just stepped backward into a single instruction function,
6535 or stepped back out of a signal handler to the first instruction
6536 of the function. Just keep going, which will single-step back
6538 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6540 struct symtab_and_line sr_sal
;
6542 /* Normal function call return (static or dynamic). */
6544 sr_sal
.pc
= ecs
->stop_func_start
;
6545 sr_sal
.pspace
= get_frame_program_space (frame
);
6546 insert_step_resume_breakpoint_at_sal (gdbarch
,
6547 sr_sal
, null_frame_id
);
6551 insert_step_resume_breakpoint_at_caller (frame
);
6557 /* If we are in a function call trampoline (a stub between the
6558 calling routine and the real function), locate the real
6559 function. That's what tells us (a) whether we want to step
6560 into it at all, and (b) what prologue we want to run to the
6561 end of, if we do step into it. */
6562 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6563 if (real_stop_pc
== 0)
6564 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6565 if (real_stop_pc
!= 0)
6566 ecs
->stop_func_start
= real_stop_pc
;
6568 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6570 struct symtab_and_line sr_sal
;
6573 sr_sal
.pc
= ecs
->stop_func_start
;
6574 sr_sal
.pspace
= get_frame_program_space (frame
);
6576 insert_step_resume_breakpoint_at_sal (gdbarch
,
6577 sr_sal
, null_frame_id
);
6582 /* If we have line number information for the function we are
6583 thinking of stepping into and the function isn't on the skip
6586 If there are several symtabs at that PC (e.g. with include
6587 files), just want to know whether *any* of them have line
6588 numbers. find_pc_line handles this. */
6590 struct symtab_and_line tmp_sal
;
6592 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6593 if (tmp_sal
.line
!= 0
6594 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6597 if (execution_direction
== EXEC_REVERSE
)
6598 handle_step_into_function_backward (gdbarch
, ecs
);
6600 handle_step_into_function (gdbarch
, ecs
);
6605 /* If we have no line number and the step-stop-if-no-debug is
6606 set, we stop the step so that the user has a chance to switch
6607 in assembly mode. */
6608 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6609 && step_stop_if_no_debug
)
6611 end_stepping_range (ecs
);
6615 if (execution_direction
== EXEC_REVERSE
)
6617 /* If we're already at the start of the function, we've either just
6618 stepped backward into a single instruction function without line
6619 number info, or stepped back out of a signal handler to the first
6620 instruction of the function without line number info. Just keep
6621 going, which will single-step back to the caller. */
6622 if (ecs
->stop_func_start
!= stop_pc
)
6624 /* Set a breakpoint at callee's start address.
6625 From there we can step once and be back in the caller. */
6626 struct symtab_and_line sr_sal
;
6629 sr_sal
.pc
= ecs
->stop_func_start
;
6630 sr_sal
.pspace
= get_frame_program_space (frame
);
6631 insert_step_resume_breakpoint_at_sal (gdbarch
,
6632 sr_sal
, null_frame_id
);
6636 /* Set a breakpoint at callee's return address (the address
6637 at which the caller will resume). */
6638 insert_step_resume_breakpoint_at_caller (frame
);
6644 /* Reverse stepping through solib trampolines. */
6646 if (execution_direction
== EXEC_REVERSE
6647 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6649 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6650 || (ecs
->stop_func_start
== 0
6651 && in_solib_dynsym_resolve_code (stop_pc
)))
6653 /* Any solib trampoline code can be handled in reverse
6654 by simply continuing to single-step. We have already
6655 executed the solib function (backwards), and a few
6656 steps will take us back through the trampoline to the
6661 else if (in_solib_dynsym_resolve_code (stop_pc
))
6663 /* Stepped backward into the solib dynsym resolver.
6664 Set a breakpoint at its start and continue, then
6665 one more step will take us out. */
6666 struct symtab_and_line sr_sal
;
6669 sr_sal
.pc
= ecs
->stop_func_start
;
6670 sr_sal
.pspace
= get_frame_program_space (frame
);
6671 insert_step_resume_breakpoint_at_sal (gdbarch
,
6672 sr_sal
, null_frame_id
);
6678 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6680 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6681 the trampoline processing logic, however, there are some trampolines
6682 that have no names, so we should do trampoline handling first. */
6683 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6684 && ecs
->stop_func_name
== NULL
6685 && stop_pc_sal
.line
== 0)
6688 fprintf_unfiltered (gdb_stdlog
,
6689 "infrun: stepped into undebuggable function\n");
6691 /* The inferior just stepped into, or returned to, an
6692 undebuggable function (where there is no debugging information
6693 and no line number corresponding to the address where the
6694 inferior stopped). Since we want to skip this kind of code,
6695 we keep going until the inferior returns from this
6696 function - unless the user has asked us not to (via
6697 set step-mode) or we no longer know how to get back
6698 to the call site. */
6699 if (step_stop_if_no_debug
6700 || !frame_id_p (frame_unwind_caller_id (frame
)))
6702 /* If we have no line number and the step-stop-if-no-debug
6703 is set, we stop the step so that the user has a chance to
6704 switch in assembly mode. */
6705 end_stepping_range (ecs
);
6710 /* Set a breakpoint at callee's return address (the address
6711 at which the caller will resume). */
6712 insert_step_resume_breakpoint_at_caller (frame
);
6718 if (ecs
->event_thread
->control
.step_range_end
== 1)
6720 /* It is stepi or nexti. We always want to stop stepping after
6723 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6724 end_stepping_range (ecs
);
6728 if (stop_pc_sal
.line
== 0)
6730 /* We have no line number information. That means to stop
6731 stepping (does this always happen right after one instruction,
6732 when we do "s" in a function with no line numbers,
6733 or can this happen as a result of a return or longjmp?). */
6735 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6736 end_stepping_range (ecs
);
6740 /* Look for "calls" to inlined functions, part one. If the inline
6741 frame machinery detected some skipped call sites, we have entered
6742 a new inline function. */
6744 if (frame_id_eq (get_frame_id (get_current_frame ()),
6745 ecs
->event_thread
->control
.step_frame_id
)
6746 && inline_skipped_frames (ecs
->ptid
))
6748 struct symtab_and_line call_sal
;
6751 fprintf_unfiltered (gdb_stdlog
,
6752 "infrun: stepped into inlined function\n");
6754 find_frame_sal (get_current_frame (), &call_sal
);
6756 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6758 /* For "step", we're going to stop. But if the call site
6759 for this inlined function is on the same source line as
6760 we were previously stepping, go down into the function
6761 first. Otherwise stop at the call site. */
6763 if (call_sal
.line
== ecs
->event_thread
->current_line
6764 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6765 step_into_inline_frame (ecs
->ptid
);
6767 end_stepping_range (ecs
);
6772 /* For "next", we should stop at the call site if it is on a
6773 different source line. Otherwise continue through the
6774 inlined function. */
6775 if (call_sal
.line
== ecs
->event_thread
->current_line
6776 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6779 end_stepping_range (ecs
);
6784 /* Look for "calls" to inlined functions, part two. If we are still
6785 in the same real function we were stepping through, but we have
6786 to go further up to find the exact frame ID, we are stepping
6787 through a more inlined call beyond its call site. */
6789 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6790 && !frame_id_eq (get_frame_id (get_current_frame ()),
6791 ecs
->event_thread
->control
.step_frame_id
)
6792 && stepped_in_from (get_current_frame (),
6793 ecs
->event_thread
->control
.step_frame_id
))
6796 fprintf_unfiltered (gdb_stdlog
,
6797 "infrun: stepping through inlined function\n");
6799 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6802 end_stepping_range (ecs
);
6806 if ((stop_pc
== stop_pc_sal
.pc
)
6807 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6808 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6810 /* We are at the start of a different line. So stop. Note that
6811 we don't stop if we step into the middle of a different line.
6812 That is said to make things like for (;;) statements work
6815 fprintf_unfiltered (gdb_stdlog
,
6816 "infrun: stepped to a different line\n");
6817 end_stepping_range (ecs
);
6821 /* We aren't done stepping.
6823 Optimize by setting the stepping range to the line.
6824 (We might not be in the original line, but if we entered a
6825 new line in mid-statement, we continue stepping. This makes
6826 things like for(;;) statements work better.) */
6828 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
6829 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
6830 ecs
->event_thread
->control
.may_range_step
= 1;
6831 set_step_info (frame
, stop_pc_sal
);
6834 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
6838 /* In all-stop mode, if we're currently stepping but have stopped in
6839 some other thread, we may need to switch back to the stepped
6840 thread. Returns true we set the inferior running, false if we left
6841 it stopped (and the event needs further processing). */
6844 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
6846 if (!target_is_non_stop_p ())
6848 struct thread_info
*tp
;
6849 struct thread_info
*stepping_thread
;
6851 /* If any thread is blocked on some internal breakpoint, and we
6852 simply need to step over that breakpoint to get it going
6853 again, do that first. */
6855 /* However, if we see an event for the stepping thread, then we
6856 know all other threads have been moved past their breakpoints
6857 already. Let the caller check whether the step is finished,
6858 etc., before deciding to move it past a breakpoint. */
6859 if (ecs
->event_thread
->control
.step_range_end
!= 0)
6862 /* Check if the current thread is blocked on an incomplete
6863 step-over, interrupted by a random signal. */
6864 if (ecs
->event_thread
->control
.trap_expected
6865 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6869 fprintf_unfiltered (gdb_stdlog
,
6870 "infrun: need to finish step-over of [%s]\n",
6871 target_pid_to_str (ecs
->event_thread
->ptid
));
6877 /* Check if the current thread is blocked by a single-step
6878 breakpoint of another thread. */
6879 if (ecs
->hit_singlestep_breakpoint
)
6883 fprintf_unfiltered (gdb_stdlog
,
6884 "infrun: need to step [%s] over single-step "
6886 target_pid_to_str (ecs
->ptid
));
6892 /* If this thread needs yet another step-over (e.g., stepping
6893 through a delay slot), do it first before moving on to
6895 if (thread_still_needs_step_over (ecs
->event_thread
))
6899 fprintf_unfiltered (gdb_stdlog
,
6900 "infrun: thread [%s] still needs step-over\n",
6901 target_pid_to_str (ecs
->event_thread
->ptid
));
6907 /* If scheduler locking applies even if not stepping, there's no
6908 need to walk over threads. Above we've checked whether the
6909 current thread is stepping. If some other thread not the
6910 event thread is stepping, then it must be that scheduler
6911 locking is not in effect. */
6912 if (schedlock_applies (ecs
->event_thread
))
6915 /* Otherwise, we no longer expect a trap in the current thread.
6916 Clear the trap_expected flag before switching back -- this is
6917 what keep_going does as well, if we call it. */
6918 ecs
->event_thread
->control
.trap_expected
= 0;
6920 /* Likewise, clear the signal if it should not be passed. */
6921 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6922 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6924 /* Do all pending step-overs before actually proceeding with
6926 if (start_step_over ())
6928 prepare_to_wait (ecs
);
6932 /* Look for the stepping/nexting thread. */
6933 stepping_thread
= NULL
;
6935 ALL_NON_EXITED_THREADS (tp
)
6937 /* Ignore threads of processes the caller is not
6940 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
6943 /* When stepping over a breakpoint, we lock all threads
6944 except the one that needs to move past the breakpoint.
6945 If a non-event thread has this set, the "incomplete
6946 step-over" check above should have caught it earlier. */
6947 if (tp
->control
.trap_expected
)
6949 internal_error (__FILE__
, __LINE__
,
6950 "[%s] has inconsistent state: "
6951 "trap_expected=%d\n",
6952 target_pid_to_str (tp
->ptid
),
6953 tp
->control
.trap_expected
);
6956 /* Did we find the stepping thread? */
6957 if (tp
->control
.step_range_end
)
6959 /* Yep. There should only one though. */
6960 gdb_assert (stepping_thread
== NULL
);
6962 /* The event thread is handled at the top, before we
6964 gdb_assert (tp
!= ecs
->event_thread
);
6966 /* If some thread other than the event thread is
6967 stepping, then scheduler locking can't be in effect,
6968 otherwise we wouldn't have resumed the current event
6969 thread in the first place. */
6970 gdb_assert (!schedlock_applies (tp
));
6972 stepping_thread
= tp
;
6976 if (stepping_thread
!= NULL
)
6979 fprintf_unfiltered (gdb_stdlog
,
6980 "infrun: switching back to stepped thread\n");
6982 if (keep_going_stepped_thread (stepping_thread
))
6984 prepare_to_wait (ecs
);
6993 /* Set a previously stepped thread back to stepping. Returns true on
6994 success, false if the resume is not possible (e.g., the thread
6998 keep_going_stepped_thread (struct thread_info
*tp
)
7000 struct frame_info
*frame
;
7001 struct gdbarch
*gdbarch
;
7002 struct execution_control_state ecss
;
7003 struct execution_control_state
*ecs
= &ecss
;
7005 /* If the stepping thread exited, then don't try to switch back and
7006 resume it, which could fail in several different ways depending
7007 on the target. Instead, just keep going.
7009 We can find a stepping dead thread in the thread list in two
7012 - The target supports thread exit events, and when the target
7013 tries to delete the thread from the thread list, inferior_ptid
7014 pointed at the exiting thread. In such case, calling
7015 delete_thread does not really remove the thread from the list;
7016 instead, the thread is left listed, with 'exited' state.
7018 - The target's debug interface does not support thread exit
7019 events, and so we have no idea whatsoever if the previously
7020 stepping thread is still alive. For that reason, we need to
7021 synchronously query the target now. */
7023 if (is_exited (tp
->ptid
)
7024 || !target_thread_alive (tp
->ptid
))
7027 fprintf_unfiltered (gdb_stdlog
,
7028 "infrun: not resuming previously "
7029 "stepped thread, it has vanished\n");
7031 delete_thread (tp
->ptid
);
7036 fprintf_unfiltered (gdb_stdlog
,
7037 "infrun: resuming previously stepped thread\n");
7039 reset_ecs (ecs
, tp
);
7040 switch_to_thread (tp
->ptid
);
7042 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7043 frame
= get_current_frame ();
7044 gdbarch
= get_frame_arch (frame
);
7046 /* If the PC of the thread we were trying to single-step has
7047 changed, then that thread has trapped or been signaled, but the
7048 event has not been reported to GDB yet. Re-poll the target
7049 looking for this particular thread's event (i.e. temporarily
7050 enable schedlock) by:
7052 - setting a break at the current PC
7053 - resuming that particular thread, only (by setting trap
7056 This prevents us continuously moving the single-step breakpoint
7057 forward, one instruction at a time, overstepping. */
7059 if (stop_pc
!= tp
->prev_pc
)
7064 fprintf_unfiltered (gdb_stdlog
,
7065 "infrun: expected thread advanced also (%s -> %s)\n",
7066 paddress (target_gdbarch (), tp
->prev_pc
),
7067 paddress (target_gdbarch (), stop_pc
));
7069 /* Clear the info of the previous step-over, as it's no longer
7070 valid (if the thread was trying to step over a breakpoint, it
7071 has already succeeded). It's what keep_going would do too,
7072 if we called it. Do this before trying to insert the sss
7073 breakpoint, otherwise if we were previously trying to step
7074 over this exact address in another thread, the breakpoint is
7076 clear_step_over_info ();
7077 tp
->control
.trap_expected
= 0;
7079 insert_single_step_breakpoint (get_frame_arch (frame
),
7080 get_frame_address_space (frame
),
7084 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7085 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7090 fprintf_unfiltered (gdb_stdlog
,
7091 "infrun: expected thread still hasn't advanced\n");
7093 keep_going_pass_signal (ecs
);
7098 /* Is thread TP in the middle of (software or hardware)
7099 single-stepping? (Note the result of this function must never be
7100 passed directly as target_resume's STEP parameter.) */
7103 currently_stepping (struct thread_info
*tp
)
7105 return ((tp
->control
.step_range_end
7106 && tp
->control
.step_resume_breakpoint
== NULL
)
7107 || tp
->control
.trap_expected
7108 || tp
->stepped_breakpoint
7109 || bpstat_should_step ());
7112 /* Inferior has stepped into a subroutine call with source code that
7113 we should not step over. Do step to the first line of code in
7117 handle_step_into_function (struct gdbarch
*gdbarch
,
7118 struct execution_control_state
*ecs
)
7120 struct compunit_symtab
*cust
;
7121 struct symtab_and_line stop_func_sal
, sr_sal
;
7123 fill_in_stop_func (gdbarch
, ecs
);
7125 cust
= find_pc_compunit_symtab (stop_pc
);
7126 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7127 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7128 ecs
->stop_func_start
);
7130 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7131 /* Use the step_resume_break to step until the end of the prologue,
7132 even if that involves jumps (as it seems to on the vax under
7134 /* If the prologue ends in the middle of a source line, continue to
7135 the end of that source line (if it is still within the function).
7136 Otherwise, just go to end of prologue. */
7137 if (stop_func_sal
.end
7138 && stop_func_sal
.pc
!= ecs
->stop_func_start
7139 && stop_func_sal
.end
< ecs
->stop_func_end
)
7140 ecs
->stop_func_start
= stop_func_sal
.end
;
7142 /* Architectures which require breakpoint adjustment might not be able
7143 to place a breakpoint at the computed address. If so, the test
7144 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7145 ecs->stop_func_start to an address at which a breakpoint may be
7146 legitimately placed.
7148 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7149 made, GDB will enter an infinite loop when stepping through
7150 optimized code consisting of VLIW instructions which contain
7151 subinstructions corresponding to different source lines. On
7152 FR-V, it's not permitted to place a breakpoint on any but the
7153 first subinstruction of a VLIW instruction. When a breakpoint is
7154 set, GDB will adjust the breakpoint address to the beginning of
7155 the VLIW instruction. Thus, we need to make the corresponding
7156 adjustment here when computing the stop address. */
7158 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7160 ecs
->stop_func_start
7161 = gdbarch_adjust_breakpoint_address (gdbarch
,
7162 ecs
->stop_func_start
);
7165 if (ecs
->stop_func_start
== stop_pc
)
7167 /* We are already there: stop now. */
7168 end_stepping_range (ecs
);
7173 /* Put the step-breakpoint there and go until there. */
7174 init_sal (&sr_sal
); /* initialize to zeroes */
7175 sr_sal
.pc
= ecs
->stop_func_start
;
7176 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7177 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7179 /* Do not specify what the fp should be when we stop since on
7180 some machines the prologue is where the new fp value is
7182 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7184 /* And make sure stepping stops right away then. */
7185 ecs
->event_thread
->control
.step_range_end
7186 = ecs
->event_thread
->control
.step_range_start
;
7191 /* Inferior has stepped backward into a subroutine call with source
7192 code that we should not step over. Do step to the beginning of the
7193 last line of code in it. */
7196 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7197 struct execution_control_state
*ecs
)
7199 struct compunit_symtab
*cust
;
7200 struct symtab_and_line stop_func_sal
;
7202 fill_in_stop_func (gdbarch
, ecs
);
7204 cust
= find_pc_compunit_symtab (stop_pc
);
7205 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7206 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7207 ecs
->stop_func_start
);
7209 stop_func_sal
= find_pc_line (stop_pc
, 0);
7211 /* OK, we're just going to keep stepping here. */
7212 if (stop_func_sal
.pc
== stop_pc
)
7214 /* We're there already. Just stop stepping now. */
7215 end_stepping_range (ecs
);
7219 /* Else just reset the step range and keep going.
7220 No step-resume breakpoint, they don't work for
7221 epilogues, which can have multiple entry paths. */
7222 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7223 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7229 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7230 This is used to both functions and to skip over code. */
7233 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7234 struct symtab_and_line sr_sal
,
7235 struct frame_id sr_id
,
7236 enum bptype sr_type
)
7238 /* There should never be more than one step-resume or longjmp-resume
7239 breakpoint per thread, so we should never be setting a new
7240 step_resume_breakpoint when one is already active. */
7241 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7242 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7245 fprintf_unfiltered (gdb_stdlog
,
7246 "infrun: inserting step-resume breakpoint at %s\n",
7247 paddress (gdbarch
, sr_sal
.pc
));
7249 inferior_thread ()->control
.step_resume_breakpoint
7250 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7254 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7255 struct symtab_and_line sr_sal
,
7256 struct frame_id sr_id
)
7258 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7263 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7264 This is used to skip a potential signal handler.
7266 This is called with the interrupted function's frame. The signal
7267 handler, when it returns, will resume the interrupted function at
7271 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7273 struct symtab_and_line sr_sal
;
7274 struct gdbarch
*gdbarch
;
7276 gdb_assert (return_frame
!= NULL
);
7277 init_sal (&sr_sal
); /* initialize to zeros */
7279 gdbarch
= get_frame_arch (return_frame
);
7280 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7281 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7282 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7284 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7285 get_stack_frame_id (return_frame
),
7289 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7290 is used to skip a function after stepping into it (for "next" or if
7291 the called function has no debugging information).
7293 The current function has almost always been reached by single
7294 stepping a call or return instruction. NEXT_FRAME belongs to the
7295 current function, and the breakpoint will be set at the caller's
7298 This is a separate function rather than reusing
7299 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7300 get_prev_frame, which may stop prematurely (see the implementation
7301 of frame_unwind_caller_id for an example). */
7304 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7306 struct symtab_and_line sr_sal
;
7307 struct gdbarch
*gdbarch
;
7309 /* We shouldn't have gotten here if we don't know where the call site
7311 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7313 init_sal (&sr_sal
); /* initialize to zeros */
7315 gdbarch
= frame_unwind_caller_arch (next_frame
);
7316 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7317 frame_unwind_caller_pc (next_frame
));
7318 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7319 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7321 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7322 frame_unwind_caller_id (next_frame
));
7325 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7326 new breakpoint at the target of a jmp_buf. The handling of
7327 longjmp-resume uses the same mechanisms used for handling
7328 "step-resume" breakpoints. */
7331 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7333 /* There should never be more than one longjmp-resume breakpoint per
7334 thread, so we should never be setting a new
7335 longjmp_resume_breakpoint when one is already active. */
7336 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7339 fprintf_unfiltered (gdb_stdlog
,
7340 "infrun: inserting longjmp-resume breakpoint at %s\n",
7341 paddress (gdbarch
, pc
));
7343 inferior_thread ()->control
.exception_resume_breakpoint
=
7344 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7347 /* Insert an exception resume breakpoint. TP is the thread throwing
7348 the exception. The block B is the block of the unwinder debug hook
7349 function. FRAME is the frame corresponding to the call to this
7350 function. SYM is the symbol of the function argument holding the
7351 target PC of the exception. */
7354 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7355 const struct block
*b
,
7356 struct frame_info
*frame
,
7361 struct block_symbol vsym
;
7362 struct value
*value
;
7364 struct breakpoint
*bp
;
7366 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
7367 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7368 /* If the value was optimized out, revert to the old behavior. */
7369 if (! value_optimized_out (value
))
7371 handler
= value_as_address (value
);
7374 fprintf_unfiltered (gdb_stdlog
,
7375 "infrun: exception resume at %lx\n",
7376 (unsigned long) handler
);
7378 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7379 handler
, bp_exception_resume
);
7381 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7384 bp
->thread
= tp
->num
;
7385 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7388 CATCH (e
, RETURN_MASK_ERROR
)
7390 /* We want to ignore errors here. */
7395 /* A helper for check_exception_resume that sets an
7396 exception-breakpoint based on a SystemTap probe. */
7399 insert_exception_resume_from_probe (struct thread_info
*tp
,
7400 const struct bound_probe
*probe
,
7401 struct frame_info
*frame
)
7403 struct value
*arg_value
;
7405 struct breakpoint
*bp
;
7407 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7411 handler
= value_as_address (arg_value
);
7414 fprintf_unfiltered (gdb_stdlog
,
7415 "infrun: exception resume at %s\n",
7416 paddress (get_objfile_arch (probe
->objfile
),
7419 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7420 handler
, bp_exception_resume
);
7421 bp
->thread
= tp
->num
;
7422 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7425 /* This is called when an exception has been intercepted. Check to
7426 see whether the exception's destination is of interest, and if so,
7427 set an exception resume breakpoint there. */
7430 check_exception_resume (struct execution_control_state
*ecs
,
7431 struct frame_info
*frame
)
7433 struct bound_probe probe
;
7434 struct symbol
*func
;
7436 /* First see if this exception unwinding breakpoint was set via a
7437 SystemTap probe point. If so, the probe has two arguments: the
7438 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7439 set a breakpoint there. */
7440 probe
= find_probe_by_pc (get_frame_pc (frame
));
7443 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7447 func
= get_frame_function (frame
);
7453 const struct block
*b
;
7454 struct block_iterator iter
;
7458 /* The exception breakpoint is a thread-specific breakpoint on
7459 the unwinder's debug hook, declared as:
7461 void _Unwind_DebugHook (void *cfa, void *handler);
7463 The CFA argument indicates the frame to which control is
7464 about to be transferred. HANDLER is the destination PC.
7466 We ignore the CFA and set a temporary breakpoint at HANDLER.
7467 This is not extremely efficient but it avoids issues in gdb
7468 with computing the DWARF CFA, and it also works even in weird
7469 cases such as throwing an exception from inside a signal
7472 b
= SYMBOL_BLOCK_VALUE (func
);
7473 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7475 if (!SYMBOL_IS_ARGUMENT (sym
))
7482 insert_exception_resume_breakpoint (ecs
->event_thread
,
7488 CATCH (e
, RETURN_MASK_ERROR
)
7495 stop_waiting (struct execution_control_state
*ecs
)
7498 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7500 clear_step_over_info ();
7502 /* Let callers know we don't want to wait for the inferior anymore. */
7503 ecs
->wait_some_more
= 0;
7505 /* If all-stop, but the target is always in non-stop mode, stop all
7506 threads now that we're presenting the stop to the user. */
7507 if (!non_stop
&& target_is_non_stop_p ())
7508 stop_all_threads ();
7511 /* Like keep_going, but passes the signal to the inferior, even if the
7512 signal is set to nopass. */
7515 keep_going_pass_signal (struct execution_control_state
*ecs
)
7517 /* Make sure normal_stop is called if we get a QUIT handled before
7519 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
7521 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7522 gdb_assert (!ecs
->event_thread
->resumed
);
7524 /* Save the pc before execution, to compare with pc after stop. */
7525 ecs
->event_thread
->prev_pc
7526 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7528 if (ecs
->event_thread
->control
.trap_expected
)
7530 struct thread_info
*tp
= ecs
->event_thread
;
7533 fprintf_unfiltered (gdb_stdlog
,
7534 "infrun: %s has trap_expected set, "
7535 "resuming to collect trap\n",
7536 target_pid_to_str (tp
->ptid
));
7538 /* We haven't yet gotten our trap, and either: intercepted a
7539 non-signal event (e.g., a fork); or took a signal which we
7540 are supposed to pass through to the inferior. Simply
7542 discard_cleanups (old_cleanups
);
7543 resume (ecs
->event_thread
->suspend
.stop_signal
);
7545 else if (step_over_info_valid_p ())
7547 /* Another thread is stepping over a breakpoint in-line. If
7548 this thread needs a step-over too, queue the request. In
7549 either case, this resume must be deferred for later. */
7550 struct thread_info
*tp
= ecs
->event_thread
;
7552 if (ecs
->hit_singlestep_breakpoint
7553 || thread_still_needs_step_over (tp
))
7556 fprintf_unfiltered (gdb_stdlog
,
7557 "infrun: step-over already in progress: "
7558 "step-over for %s deferred\n",
7559 target_pid_to_str (tp
->ptid
));
7560 thread_step_over_chain_enqueue (tp
);
7565 fprintf_unfiltered (gdb_stdlog
,
7566 "infrun: step-over in progress: "
7567 "resume of %s deferred\n",
7568 target_pid_to_str (tp
->ptid
));
7571 discard_cleanups (old_cleanups
);
7575 struct regcache
*regcache
= get_current_regcache ();
7578 enum step_over_what step_what
;
7580 /* Either the trap was not expected, but we are continuing
7581 anyway (if we got a signal, the user asked it be passed to
7584 We got our expected trap, but decided we should resume from
7587 We're going to run this baby now!
7589 Note that insert_breakpoints won't try to re-insert
7590 already inserted breakpoints. Therefore, we don't
7591 care if breakpoints were already inserted, or not. */
7593 /* If we need to step over a breakpoint, and we're not using
7594 displaced stepping to do so, insert all breakpoints
7595 (watchpoints, etc.) but the one we're stepping over, step one
7596 instruction, and then re-insert the breakpoint when that step
7599 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7601 remove_bp
= (ecs
->hit_singlestep_breakpoint
7602 || (step_what
& STEP_OVER_BREAKPOINT
));
7603 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7605 /* We can't use displaced stepping if we need to step past a
7606 watchpoint. The instruction copied to the scratch pad would
7607 still trigger the watchpoint. */
7609 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7611 set_step_over_info (get_regcache_aspace (regcache
),
7612 regcache_read_pc (regcache
), remove_wps
);
7614 else if (remove_wps
)
7615 set_step_over_info (NULL
, 0, remove_wps
);
7617 /* If we now need to do an in-line step-over, we need to stop
7618 all other threads. Note this must be done before
7619 insert_breakpoints below, because that removes the breakpoint
7620 we're about to step over, otherwise other threads could miss
7622 if (step_over_info_valid_p () && target_is_non_stop_p ())
7623 stop_all_threads ();
7625 /* Stop stepping if inserting breakpoints fails. */
7628 insert_breakpoints ();
7630 CATCH (e
, RETURN_MASK_ERROR
)
7632 exception_print (gdb_stderr
, e
);
7634 discard_cleanups (old_cleanups
);
7639 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7641 discard_cleanups (old_cleanups
);
7642 resume (ecs
->event_thread
->suspend
.stop_signal
);
7645 prepare_to_wait (ecs
);
7648 /* Called when we should continue running the inferior, because the
7649 current event doesn't cause a user visible stop. This does the
7650 resuming part; waiting for the next event is done elsewhere. */
7653 keep_going (struct execution_control_state
*ecs
)
7655 if (ecs
->event_thread
->control
.trap_expected
7656 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7657 ecs
->event_thread
->control
.trap_expected
= 0;
7659 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7660 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7661 keep_going_pass_signal (ecs
);
7664 /* This function normally comes after a resume, before
7665 handle_inferior_event exits. It takes care of any last bits of
7666 housekeeping, and sets the all-important wait_some_more flag. */
7669 prepare_to_wait (struct execution_control_state
*ecs
)
7672 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7674 ecs
->wait_some_more
= 1;
7676 if (!target_is_async_p ())
7677 mark_infrun_async_event_handler ();
7680 /* We are done with the step range of a step/next/si/ni command.
7681 Called once for each n of a "step n" operation. */
7684 end_stepping_range (struct execution_control_state
*ecs
)
7686 ecs
->event_thread
->control
.stop_step
= 1;
7690 /* Several print_*_reason functions to print why the inferior has stopped.
7691 We always print something when the inferior exits, or receives a signal.
7692 The rest of the cases are dealt with later on in normal_stop and
7693 print_it_typical. Ideally there should be a call to one of these
7694 print_*_reason functions functions from handle_inferior_event each time
7695 stop_waiting is called.
7697 Note that we don't call these directly, instead we delegate that to
7698 the interpreters, through observers. Interpreters then call these
7699 with whatever uiout is right. */
7702 print_end_stepping_range_reason (struct ui_out
*uiout
)
7704 /* For CLI-like interpreters, print nothing. */
7706 if (ui_out_is_mi_like_p (uiout
))
7708 ui_out_field_string (uiout
, "reason",
7709 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7714 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7716 annotate_signalled ();
7717 if (ui_out_is_mi_like_p (uiout
))
7719 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7720 ui_out_text (uiout
, "\nProgram terminated with signal ");
7721 annotate_signal_name ();
7722 ui_out_field_string (uiout
, "signal-name",
7723 gdb_signal_to_name (siggnal
));
7724 annotate_signal_name_end ();
7725 ui_out_text (uiout
, ", ");
7726 annotate_signal_string ();
7727 ui_out_field_string (uiout
, "signal-meaning",
7728 gdb_signal_to_string (siggnal
));
7729 annotate_signal_string_end ();
7730 ui_out_text (uiout
, ".\n");
7731 ui_out_text (uiout
, "The program no longer exists.\n");
7735 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7737 struct inferior
*inf
= current_inferior ();
7738 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7740 annotate_exited (exitstatus
);
7743 if (ui_out_is_mi_like_p (uiout
))
7744 ui_out_field_string (uiout
, "reason",
7745 async_reason_lookup (EXEC_ASYNC_EXITED
));
7746 ui_out_text (uiout
, "[Inferior ");
7747 ui_out_text (uiout
, plongest (inf
->num
));
7748 ui_out_text (uiout
, " (");
7749 ui_out_text (uiout
, pidstr
);
7750 ui_out_text (uiout
, ") exited with code ");
7751 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
7752 ui_out_text (uiout
, "]\n");
7756 if (ui_out_is_mi_like_p (uiout
))
7758 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7759 ui_out_text (uiout
, "[Inferior ");
7760 ui_out_text (uiout
, plongest (inf
->num
));
7761 ui_out_text (uiout
, " (");
7762 ui_out_text (uiout
, pidstr
);
7763 ui_out_text (uiout
, ") exited normally]\n");
7768 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7772 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
7774 struct thread_info
*t
= inferior_thread ();
7776 ui_out_text (uiout
, "\n[");
7777 ui_out_field_string (uiout
, "thread-name",
7778 target_pid_to_str (t
->ptid
));
7779 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
7780 ui_out_text (uiout
, " stopped");
7784 ui_out_text (uiout
, "\nProgram received signal ");
7785 annotate_signal_name ();
7786 if (ui_out_is_mi_like_p (uiout
))
7788 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
7789 ui_out_field_string (uiout
, "signal-name",
7790 gdb_signal_to_name (siggnal
));
7791 annotate_signal_name_end ();
7792 ui_out_text (uiout
, ", ");
7793 annotate_signal_string ();
7794 ui_out_field_string (uiout
, "signal-meaning",
7795 gdb_signal_to_string (siggnal
));
7796 annotate_signal_string_end ();
7798 ui_out_text (uiout
, ".\n");
7802 print_no_history_reason (struct ui_out
*uiout
)
7804 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
7807 /* Print current location without a level number, if we have changed
7808 functions or hit a breakpoint. Print source line if we have one.
7809 bpstat_print contains the logic deciding in detail what to print,
7810 based on the event(s) that just occurred. */
7813 print_stop_location (struct target_waitstatus
*ws
)
7816 enum print_what source_flag
;
7817 int do_frame_printing
= 1;
7818 struct thread_info
*tp
= inferior_thread ();
7820 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
7824 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
7825 should) carry around the function and does (or should) use
7826 that when doing a frame comparison. */
7827 if (tp
->control
.stop_step
7828 && frame_id_eq (tp
->control
.step_frame_id
,
7829 get_frame_id (get_current_frame ()))
7830 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
7832 /* Finished step, just print source line. */
7833 source_flag
= SRC_LINE
;
7837 /* Print location and source line. */
7838 source_flag
= SRC_AND_LOC
;
7841 case PRINT_SRC_AND_LOC
:
7842 /* Print location and source line. */
7843 source_flag
= SRC_AND_LOC
;
7845 case PRINT_SRC_ONLY
:
7846 source_flag
= SRC_LINE
;
7849 /* Something bogus. */
7850 source_flag
= SRC_LINE
;
7851 do_frame_printing
= 0;
7854 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
7857 /* The behavior of this routine with respect to the source
7859 SRC_LINE: Print only source line
7860 LOCATION: Print only location
7861 SRC_AND_LOC: Print location and source line. */
7862 if (do_frame_printing
)
7863 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
7866 /* Cleanup that restores a previous current uiout. */
7869 restore_current_uiout_cleanup (void *arg
)
7871 struct ui_out
*saved_uiout
= (struct ui_out
*) arg
;
7873 current_uiout
= saved_uiout
;
7879 print_stop_event (struct ui_out
*uiout
)
7881 struct cleanup
*old_chain
;
7882 struct target_waitstatus last
;
7884 struct thread_info
*tp
;
7886 get_last_target_status (&last_ptid
, &last
);
7888 old_chain
= make_cleanup (restore_current_uiout_cleanup
, current_uiout
);
7889 current_uiout
= uiout
;
7891 print_stop_location (&last
);
7893 /* Display the auto-display expressions. */
7896 do_cleanups (old_chain
);
7898 tp
= inferior_thread ();
7899 if (tp
->thread_fsm
!= NULL
7900 && thread_fsm_finished_p (tp
->thread_fsm
))
7902 struct return_value_info
*rv
;
7904 rv
= thread_fsm_return_value (tp
->thread_fsm
);
7906 print_return_value (uiout
, rv
);
7913 maybe_remove_breakpoints (void)
7915 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
7917 if (remove_breakpoints ())
7919 target_terminal_ours_for_output ();
7920 printf_filtered (_("Cannot remove breakpoints because "
7921 "program is no longer writable.\nFurther "
7922 "execution is probably impossible.\n"));
7927 /* The execution context that just caused a normal stop. */
7934 /* The event PTID. */
7938 /* If stopp for a thread event, this is the thread that caused the
7940 struct thread_info
*thread
;
7942 /* The inferior that caused the stop. */
7946 /* Returns a new stop context. If stopped for a thread event, this
7947 takes a strong reference to the thread. */
7949 static struct stop_context
*
7950 save_stop_context (void)
7952 struct stop_context
*sc
= XNEW (struct stop_context
);
7954 sc
->stop_id
= get_stop_id ();
7955 sc
->ptid
= inferior_ptid
;
7956 sc
->inf_num
= current_inferior ()->num
;
7958 if (!ptid_equal (inferior_ptid
, null_ptid
))
7960 /* Take a strong reference so that the thread can't be deleted
7962 sc
->thread
= inferior_thread ();
7963 sc
->thread
->refcount
++;
7971 /* Release a stop context previously created with save_stop_context.
7972 Releases the strong reference to the thread as well. */
7975 release_stop_context_cleanup (void *arg
)
7977 struct stop_context
*sc
= (struct stop_context
*) arg
;
7979 if (sc
->thread
!= NULL
)
7980 sc
->thread
->refcount
--;
7984 /* Return true if the current context no longer matches the saved stop
7988 stop_context_changed (struct stop_context
*prev
)
7990 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
7992 if (prev
->inf_num
!= current_inferior ()->num
)
7994 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
7996 if (get_stop_id () != prev
->stop_id
)
8006 struct target_waitstatus last
;
8008 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
8011 get_last_target_status (&last_ptid
, &last
);
8015 /* If an exception is thrown from this point on, make sure to
8016 propagate GDB's knowledge of the executing state to the
8017 frontend/user running state. A QUIT is an easy exception to see
8018 here, so do this before any filtered output. */
8020 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
8021 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8022 || last
.kind
== TARGET_WAITKIND_EXITED
)
8024 /* On some targets, we may still have live threads in the
8025 inferior when we get a process exit event. E.g., for
8026 "checkpoint", when the current checkpoint/fork exits,
8027 linux-fork.c automatically switches to another fork from
8028 within target_mourn_inferior. */
8029 if (!ptid_equal (inferior_ptid
, null_ptid
))
8031 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8032 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8035 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8036 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8038 /* As we're presenting a stop, and potentially removing breakpoints,
8039 update the thread list so we can tell whether there are threads
8040 running on the target. With target remote, for example, we can
8041 only learn about new threads when we explicitly update the thread
8042 list. Do this before notifying the interpreters about signal
8043 stops, end of stepping ranges, etc., so that the "new thread"
8044 output is emitted before e.g., "Program received signal FOO",
8045 instead of after. */
8046 update_thread_list ();
8048 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8049 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
8051 /* As with the notification of thread events, we want to delay
8052 notifying the user that we've switched thread context until
8053 the inferior actually stops.
8055 There's no point in saying anything if the inferior has exited.
8056 Note that SIGNALLED here means "exited with a signal", not
8057 "received a signal".
8059 Also skip saying anything in non-stop mode. In that mode, as we
8060 don't want GDB to switch threads behind the user's back, to avoid
8061 races where the user is typing a command to apply to thread x,
8062 but GDB switches to thread y before the user finishes entering
8063 the command, fetch_inferior_event installs a cleanup to restore
8064 the current thread back to the thread the user had selected right
8065 after this event is handled, so we're not really switching, only
8066 informing of a stop. */
8068 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8069 && target_has_execution
8070 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8071 && last
.kind
!= TARGET_WAITKIND_EXITED
8072 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8074 target_terminal_ours_for_output ();
8075 printf_filtered (_("[Switching to %s]\n"),
8076 target_pid_to_str (inferior_ptid
));
8077 annotate_thread_changed ();
8078 previous_inferior_ptid
= inferior_ptid
;
8081 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8083 gdb_assert (sync_execution
|| !target_can_async_p ());
8085 target_terminal_ours_for_output ();
8086 printf_filtered (_("No unwaited-for children left.\n"));
8089 /* Note: this depends on the update_thread_list call above. */
8090 maybe_remove_breakpoints ();
8092 /* If an auto-display called a function and that got a signal,
8093 delete that auto-display to avoid an infinite recursion. */
8095 if (stopped_by_random_signal
)
8096 disable_current_display ();
8098 target_terminal_ours ();
8099 async_enable_stdin ();
8101 /* Let the user/frontend see the threads as stopped. */
8102 do_cleanups (old_chain
);
8104 /* Select innermost stack frame - i.e., current frame is frame 0,
8105 and current location is based on that. Handle the case where the
8106 dummy call is returning after being stopped. E.g. the dummy call
8107 previously hit a breakpoint. (If the dummy call returns
8108 normally, we won't reach here.) Do this before the stop hook is
8109 run, so that it doesn't get to see the temporary dummy frame,
8110 which is not where we'll present the stop. */
8111 if (has_stack_frames ())
8113 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8115 /* Pop the empty frame that contains the stack dummy. This
8116 also restores inferior state prior to the call (struct
8117 infcall_suspend_state). */
8118 struct frame_info
*frame
= get_current_frame ();
8120 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8122 /* frame_pop calls reinit_frame_cache as the last thing it
8123 does which means there's now no selected frame. */
8126 select_frame (get_current_frame ());
8128 /* Set the current source location. */
8129 set_current_sal_from_frame (get_current_frame ());
8132 /* Look up the hook_stop and run it (CLI internally handles problem
8133 of stop_command's pre-hook not existing). */
8134 if (stop_command
!= NULL
)
8136 struct stop_context
*saved_context
= save_stop_context ();
8137 struct cleanup
*old_chain
8138 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8140 catch_errors (hook_stop_stub
, stop_command
,
8141 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
8143 /* If the stop hook resumes the target, then there's no point in
8144 trying to notify about the previous stop; its context is
8145 gone. Likewise if the command switches thread or inferior --
8146 the observers would print a stop for the wrong
8148 if (stop_context_changed (saved_context
))
8150 do_cleanups (old_chain
);
8153 do_cleanups (old_chain
);
8156 /* Notify observers about the stop. This is where the interpreters
8157 print the stop event. */
8158 if (!ptid_equal (inferior_ptid
, null_ptid
))
8159 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
8162 observer_notify_normal_stop (NULL
, stop_print_frame
);
8164 annotate_stopped ();
8166 if (target_has_execution
)
8168 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8169 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8170 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8171 Delete any breakpoint that is to be deleted at the next stop. */
8172 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8175 /* Try to get rid of automatically added inferiors that are no
8176 longer needed. Keeping those around slows down things linearly.
8177 Note that this never removes the current inferior. */
8184 hook_stop_stub (void *cmd
)
8186 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
8191 signal_stop_state (int signo
)
8193 return signal_stop
[signo
];
8197 signal_print_state (int signo
)
8199 return signal_print
[signo
];
8203 signal_pass_state (int signo
)
8205 return signal_program
[signo
];
8209 signal_cache_update (int signo
)
8213 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8214 signal_cache_update (signo
);
8219 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8220 && signal_print
[signo
] == 0
8221 && signal_program
[signo
] == 1
8222 && signal_catch
[signo
] == 0);
8226 signal_stop_update (int signo
, int state
)
8228 int ret
= signal_stop
[signo
];
8230 signal_stop
[signo
] = state
;
8231 signal_cache_update (signo
);
8236 signal_print_update (int signo
, int state
)
8238 int ret
= signal_print
[signo
];
8240 signal_print
[signo
] = state
;
8241 signal_cache_update (signo
);
8246 signal_pass_update (int signo
, int state
)
8248 int ret
= signal_program
[signo
];
8250 signal_program
[signo
] = state
;
8251 signal_cache_update (signo
);
8255 /* Update the global 'signal_catch' from INFO and notify the
8259 signal_catch_update (const unsigned int *info
)
8263 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8264 signal_catch
[i
] = info
[i
] > 0;
8265 signal_cache_update (-1);
8266 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8270 sig_print_header (void)
8272 printf_filtered (_("Signal Stop\tPrint\tPass "
8273 "to program\tDescription\n"));
8277 sig_print_info (enum gdb_signal oursig
)
8279 const char *name
= gdb_signal_to_name (oursig
);
8280 int name_padding
= 13 - strlen (name
);
8282 if (name_padding
<= 0)
8285 printf_filtered ("%s", name
);
8286 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8287 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8288 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8289 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8290 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8293 /* Specify how various signals in the inferior should be handled. */
8296 handle_command (char *args
, int from_tty
)
8299 int digits
, wordlen
;
8300 int sigfirst
, signum
, siglast
;
8301 enum gdb_signal oursig
;
8304 unsigned char *sigs
;
8305 struct cleanup
*old_chain
;
8309 error_no_arg (_("signal to handle"));
8312 /* Allocate and zero an array of flags for which signals to handle. */
8314 nsigs
= (int) GDB_SIGNAL_LAST
;
8315 sigs
= (unsigned char *) alloca (nsigs
);
8316 memset (sigs
, 0, nsigs
);
8318 /* Break the command line up into args. */
8320 argv
= gdb_buildargv (args
);
8321 old_chain
= make_cleanup_freeargv (argv
);
8323 /* Walk through the args, looking for signal oursigs, signal names, and
8324 actions. Signal numbers and signal names may be interspersed with
8325 actions, with the actions being performed for all signals cumulatively
8326 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8328 while (*argv
!= NULL
)
8330 wordlen
= strlen (*argv
);
8331 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
8335 sigfirst
= siglast
= -1;
8337 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
8339 /* Apply action to all signals except those used by the
8340 debugger. Silently skip those. */
8343 siglast
= nsigs
- 1;
8345 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
8347 SET_SIGS (nsigs
, sigs
, signal_stop
);
8348 SET_SIGS (nsigs
, sigs
, signal_print
);
8350 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
8352 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8354 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
8356 SET_SIGS (nsigs
, sigs
, signal_print
);
8358 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
8360 SET_SIGS (nsigs
, sigs
, signal_program
);
8362 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
8364 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8366 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
8368 SET_SIGS (nsigs
, sigs
, signal_program
);
8370 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
8372 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8373 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8375 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
8377 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8379 else if (digits
> 0)
8381 /* It is numeric. The numeric signal refers to our own
8382 internal signal numbering from target.h, not to host/target
8383 signal number. This is a feature; users really should be
8384 using symbolic names anyway, and the common ones like
8385 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8387 sigfirst
= siglast
= (int)
8388 gdb_signal_from_command (atoi (*argv
));
8389 if ((*argv
)[digits
] == '-')
8392 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
8394 if (sigfirst
> siglast
)
8396 /* Bet he didn't figure we'd think of this case... */
8404 oursig
= gdb_signal_from_name (*argv
);
8405 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8407 sigfirst
= siglast
= (int) oursig
;
8411 /* Not a number and not a recognized flag word => complain. */
8412 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
8416 /* If any signal numbers or symbol names were found, set flags for
8417 which signals to apply actions to. */
8419 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8421 switch ((enum gdb_signal
) signum
)
8423 case GDB_SIGNAL_TRAP
:
8424 case GDB_SIGNAL_INT
:
8425 if (!allsigs
&& !sigs
[signum
])
8427 if (query (_("%s is used by the debugger.\n\
8428 Are you sure you want to change it? "),
8429 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8435 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8436 gdb_flush (gdb_stdout
);
8441 case GDB_SIGNAL_DEFAULT
:
8442 case GDB_SIGNAL_UNKNOWN
:
8443 /* Make sure that "all" doesn't print these. */
8454 for (signum
= 0; signum
< nsigs
; signum
++)
8457 signal_cache_update (-1);
8458 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8459 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8463 /* Show the results. */
8464 sig_print_header ();
8465 for (; signum
< nsigs
; signum
++)
8467 sig_print_info ((enum gdb_signal
) signum
);
8473 do_cleanups (old_chain
);
8476 /* Complete the "handle" command. */
8478 static VEC (char_ptr
) *
8479 handle_completer (struct cmd_list_element
*ignore
,
8480 const char *text
, const char *word
)
8482 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
8483 static const char * const keywords
[] =
8497 vec_signals
= signal_completer (ignore
, text
, word
);
8498 vec_keywords
= complete_on_enum (keywords
, word
, word
);
8500 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
8501 VEC_free (char_ptr
, vec_signals
);
8502 VEC_free (char_ptr
, vec_keywords
);
8507 gdb_signal_from_command (int num
)
8509 if (num
>= 1 && num
<= 15)
8510 return (enum gdb_signal
) num
;
8511 error (_("Only signals 1-15 are valid as numeric signals.\n\
8512 Use \"info signals\" for a list of symbolic signals."));
8515 /* Print current contents of the tables set by the handle command.
8516 It is possible we should just be printing signals actually used
8517 by the current target (but for things to work right when switching
8518 targets, all signals should be in the signal tables). */
8521 signals_info (char *signum_exp
, int from_tty
)
8523 enum gdb_signal oursig
;
8525 sig_print_header ();
8529 /* First see if this is a symbol name. */
8530 oursig
= gdb_signal_from_name (signum_exp
);
8531 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8533 /* No, try numeric. */
8535 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8537 sig_print_info (oursig
);
8541 printf_filtered ("\n");
8542 /* These ugly casts brought to you by the native VAX compiler. */
8543 for (oursig
= GDB_SIGNAL_FIRST
;
8544 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8545 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8549 if (oursig
!= GDB_SIGNAL_UNKNOWN
8550 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8551 sig_print_info (oursig
);
8554 printf_filtered (_("\nUse the \"handle\" command "
8555 "to change these tables.\n"));
8558 /* Check if it makes sense to read $_siginfo from the current thread
8559 at this point. If not, throw an error. */
8562 validate_siginfo_access (void)
8564 /* No current inferior, no siginfo. */
8565 if (ptid_equal (inferior_ptid
, null_ptid
))
8566 error (_("No thread selected."));
8568 /* Don't try to read from a dead thread. */
8569 if (is_exited (inferior_ptid
))
8570 error (_("The current thread has terminated"));
8572 /* ... or from a spinning thread. */
8573 if (is_running (inferior_ptid
))
8574 error (_("Selected thread is running."));
8577 /* The $_siginfo convenience variable is a bit special. We don't know
8578 for sure the type of the value until we actually have a chance to
8579 fetch the data. The type can change depending on gdbarch, so it is
8580 also dependent on which thread you have selected.
8582 1. making $_siginfo be an internalvar that creates a new value on
8585 2. making the value of $_siginfo be an lval_computed value. */
8587 /* This function implements the lval_computed support for reading a
8591 siginfo_value_read (struct value
*v
)
8593 LONGEST transferred
;
8595 validate_siginfo_access ();
8598 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8600 value_contents_all_raw (v
),
8602 TYPE_LENGTH (value_type (v
)));
8604 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8605 error (_("Unable to read siginfo"));
8608 /* This function implements the lval_computed support for writing a
8612 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8614 LONGEST transferred
;
8616 validate_siginfo_access ();
8618 transferred
= target_write (¤t_target
,
8619 TARGET_OBJECT_SIGNAL_INFO
,
8621 value_contents_all_raw (fromval
),
8623 TYPE_LENGTH (value_type (fromval
)));
8625 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8626 error (_("Unable to write siginfo"));
8629 static const struct lval_funcs siginfo_value_funcs
=
8635 /* Return a new value with the correct type for the siginfo object of
8636 the current thread using architecture GDBARCH. Return a void value
8637 if there's no object available. */
8639 static struct value
*
8640 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8643 if (target_has_stack
8644 && !ptid_equal (inferior_ptid
, null_ptid
)
8645 && gdbarch_get_siginfo_type_p (gdbarch
))
8647 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8649 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8652 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8656 /* infcall_suspend_state contains state about the program itself like its
8657 registers and any signal it received when it last stopped.
8658 This state must be restored regardless of how the inferior function call
8659 ends (either successfully, or after it hits a breakpoint or signal)
8660 if the program is to properly continue where it left off. */
8662 struct infcall_suspend_state
8664 struct thread_suspend_state thread_suspend
;
8668 struct regcache
*registers
;
8670 /* Format of SIGINFO_DATA or NULL if it is not present. */
8671 struct gdbarch
*siginfo_gdbarch
;
8673 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8674 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8675 content would be invalid. */
8676 gdb_byte
*siginfo_data
;
8679 struct infcall_suspend_state
*
8680 save_infcall_suspend_state (void)
8682 struct infcall_suspend_state
*inf_state
;
8683 struct thread_info
*tp
= inferior_thread ();
8684 struct regcache
*regcache
= get_current_regcache ();
8685 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8686 gdb_byte
*siginfo_data
= NULL
;
8688 if (gdbarch_get_siginfo_type_p (gdbarch
))
8690 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8691 size_t len
= TYPE_LENGTH (type
);
8692 struct cleanup
*back_to
;
8694 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8695 back_to
= make_cleanup (xfree
, siginfo_data
);
8697 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8698 siginfo_data
, 0, len
) == len
)
8699 discard_cleanups (back_to
);
8702 /* Errors ignored. */
8703 do_cleanups (back_to
);
8704 siginfo_data
= NULL
;
8708 inf_state
= XCNEW (struct infcall_suspend_state
);
8712 inf_state
->siginfo_gdbarch
= gdbarch
;
8713 inf_state
->siginfo_data
= siginfo_data
;
8716 inf_state
->thread_suspend
= tp
->suspend
;
8718 /* run_inferior_call will not use the signal due to its `proceed' call with
8719 GDB_SIGNAL_0 anyway. */
8720 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8722 inf_state
->stop_pc
= stop_pc
;
8724 inf_state
->registers
= regcache_dup (regcache
);
8729 /* Restore inferior session state to INF_STATE. */
8732 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8734 struct thread_info
*tp
= inferior_thread ();
8735 struct regcache
*regcache
= get_current_regcache ();
8736 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8738 tp
->suspend
= inf_state
->thread_suspend
;
8740 stop_pc
= inf_state
->stop_pc
;
8742 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8744 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8746 /* Errors ignored. */
8747 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8748 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8751 /* The inferior can be gone if the user types "print exit(0)"
8752 (and perhaps other times). */
8753 if (target_has_execution
)
8754 /* NB: The register write goes through to the target. */
8755 regcache_cpy (regcache
, inf_state
->registers
);
8757 discard_infcall_suspend_state (inf_state
);
8761 do_restore_infcall_suspend_state_cleanup (void *state
)
8763 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
8767 make_cleanup_restore_infcall_suspend_state
8768 (struct infcall_suspend_state
*inf_state
)
8770 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8774 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8776 regcache_xfree (inf_state
->registers
);
8777 xfree (inf_state
->siginfo_data
);
8782 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8784 return inf_state
->registers
;
8787 /* infcall_control_state contains state regarding gdb's control of the
8788 inferior itself like stepping control. It also contains session state like
8789 the user's currently selected frame. */
8791 struct infcall_control_state
8793 struct thread_control_state thread_control
;
8794 struct inferior_control_state inferior_control
;
8797 enum stop_stack_kind stop_stack_dummy
;
8798 int stopped_by_random_signal
;
8800 /* ID if the selected frame when the inferior function call was made. */
8801 struct frame_id selected_frame_id
;
8804 /* Save all of the information associated with the inferior<==>gdb
8807 struct infcall_control_state
*
8808 save_infcall_control_state (void)
8810 struct infcall_control_state
*inf_status
=
8811 XNEW (struct infcall_control_state
);
8812 struct thread_info
*tp
= inferior_thread ();
8813 struct inferior
*inf
= current_inferior ();
8815 inf_status
->thread_control
= tp
->control
;
8816 inf_status
->inferior_control
= inf
->control
;
8818 tp
->control
.step_resume_breakpoint
= NULL
;
8819 tp
->control
.exception_resume_breakpoint
= NULL
;
8821 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8822 chain. If caller's caller is walking the chain, they'll be happier if we
8823 hand them back the original chain when restore_infcall_control_state is
8825 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
8828 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
8829 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
8831 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
8837 restore_selected_frame (void *args
)
8839 struct frame_id
*fid
= (struct frame_id
*) args
;
8840 struct frame_info
*frame
;
8842 frame
= frame_find_by_id (*fid
);
8844 /* If inf_status->selected_frame_id is NULL, there was no previously
8848 warning (_("Unable to restore previously selected frame."));
8852 select_frame (frame
);
8857 /* Restore inferior session state to INF_STATUS. */
8860 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
8862 struct thread_info
*tp
= inferior_thread ();
8863 struct inferior
*inf
= current_inferior ();
8865 if (tp
->control
.step_resume_breakpoint
)
8866 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
8868 if (tp
->control
.exception_resume_breakpoint
)
8869 tp
->control
.exception_resume_breakpoint
->disposition
8870 = disp_del_at_next_stop
;
8872 /* Handle the bpstat_copy of the chain. */
8873 bpstat_clear (&tp
->control
.stop_bpstat
);
8875 tp
->control
= inf_status
->thread_control
;
8876 inf
->control
= inf_status
->inferior_control
;
8879 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
8880 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
8882 if (target_has_stack
)
8884 /* The point of catch_errors is that if the stack is clobbered,
8885 walking the stack might encounter a garbage pointer and
8886 error() trying to dereference it. */
8888 (restore_selected_frame
, &inf_status
->selected_frame_id
,
8889 "Unable to restore previously selected frame:\n",
8890 RETURN_MASK_ERROR
) == 0)
8891 /* Error in restoring the selected frame. Select the innermost
8893 select_frame (get_current_frame ());
8900 do_restore_infcall_control_state_cleanup (void *sts
)
8902 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
8906 make_cleanup_restore_infcall_control_state
8907 (struct infcall_control_state
*inf_status
)
8909 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
8913 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
8915 if (inf_status
->thread_control
.step_resume_breakpoint
)
8916 inf_status
->thread_control
.step_resume_breakpoint
->disposition
8917 = disp_del_at_next_stop
;
8919 if (inf_status
->thread_control
.exception_resume_breakpoint
)
8920 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
8921 = disp_del_at_next_stop
;
8923 /* See save_infcall_control_state for info on stop_bpstat. */
8924 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
8929 /* restore_inferior_ptid() will be used by the cleanup machinery
8930 to restore the inferior_ptid value saved in a call to
8931 save_inferior_ptid(). */
8934 restore_inferior_ptid (void *arg
)
8936 ptid_t
*saved_ptid_ptr
= (ptid_t
*) arg
;
8938 inferior_ptid
= *saved_ptid_ptr
;
8942 /* Save the value of inferior_ptid so that it may be restored by a
8943 later call to do_cleanups(). Returns the struct cleanup pointer
8944 needed for later doing the cleanup. */
8947 save_inferior_ptid (void)
8949 ptid_t
*saved_ptid_ptr
= XNEW (ptid_t
);
8951 *saved_ptid_ptr
= inferior_ptid
;
8952 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
8958 clear_exit_convenience_vars (void)
8960 clear_internalvar (lookup_internalvar ("_exitsignal"));
8961 clear_internalvar (lookup_internalvar ("_exitcode"));
8965 /* User interface for reverse debugging:
8966 Set exec-direction / show exec-direction commands
8967 (returns error unless target implements to_set_exec_direction method). */
8969 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
8970 static const char exec_forward
[] = "forward";
8971 static const char exec_reverse
[] = "reverse";
8972 static const char *exec_direction
= exec_forward
;
8973 static const char *const exec_direction_names
[] = {
8980 set_exec_direction_func (char *args
, int from_tty
,
8981 struct cmd_list_element
*cmd
)
8983 if (target_can_execute_reverse
)
8985 if (!strcmp (exec_direction
, exec_forward
))
8986 execution_direction
= EXEC_FORWARD
;
8987 else if (!strcmp (exec_direction
, exec_reverse
))
8988 execution_direction
= EXEC_REVERSE
;
8992 exec_direction
= exec_forward
;
8993 error (_("Target does not support this operation."));
8998 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
8999 struct cmd_list_element
*cmd
, const char *value
)
9001 switch (execution_direction
) {
9003 fprintf_filtered (out
, _("Forward.\n"));
9006 fprintf_filtered (out
, _("Reverse.\n"));
9009 internal_error (__FILE__
, __LINE__
,
9010 _("bogus execution_direction value: %d"),
9011 (int) execution_direction
);
9016 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9017 struct cmd_list_element
*c
, const char *value
)
9019 fprintf_filtered (file
, _("Resuming the execution of threads "
9020 "of all processes is %s.\n"), value
);
9023 /* Implementation of `siginfo' variable. */
9025 static const struct internalvar_funcs siginfo_funcs
=
9032 /* Callback for infrun's target events source. This is marked when a
9033 thread has a pending status to process. */
9036 infrun_async_inferior_event_handler (gdb_client_data data
)
9038 inferior_event_handler (INF_REG_EVENT
, NULL
);
9042 _initialize_infrun (void)
9046 struct cmd_list_element
*c
;
9048 /* Register extra event sources in the event loop. */
9049 infrun_async_inferior_event_token
9050 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9052 add_info ("signals", signals_info
, _("\
9053 What debugger does when program gets various signals.\n\
9054 Specify a signal as argument to print info on that signal only."));
9055 add_info_alias ("handle", "signals", 0);
9057 c
= add_com ("handle", class_run
, handle_command
, _("\
9058 Specify how to handle signals.\n\
9059 Usage: handle SIGNAL [ACTIONS]\n\
9060 Args are signals and actions to apply to those signals.\n\
9061 If no actions are specified, the current settings for the specified signals\n\
9062 will be displayed instead.\n\
9064 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9065 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9066 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9067 The special arg \"all\" is recognized to mean all signals except those\n\
9068 used by the debugger, typically SIGTRAP and SIGINT.\n\
9070 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9071 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9072 Stop means reenter debugger if this signal happens (implies print).\n\
9073 Print means print a message if this signal happens.\n\
9074 Pass means let program see this signal; otherwise program doesn't know.\n\
9075 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9076 Pass and Stop may be combined.\n\
9078 Multiple signals may be specified. Signal numbers and signal names\n\
9079 may be interspersed with actions, with the actions being performed for\n\
9080 all signals cumulatively specified."));
9081 set_cmd_completer (c
, handle_completer
);
9084 stop_command
= add_cmd ("stop", class_obscure
,
9085 not_just_help_class_command
, _("\
9086 There is no `stop' command, but you can set a hook on `stop'.\n\
9087 This allows you to set a list of commands to be run each time execution\n\
9088 of the program stops."), &cmdlist
);
9090 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9091 Set inferior debugging."), _("\
9092 Show inferior debugging."), _("\
9093 When non-zero, inferior specific debugging is enabled."),
9096 &setdebuglist
, &showdebuglist
);
9098 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9099 &debug_displaced
, _("\
9100 Set displaced stepping debugging."), _("\
9101 Show displaced stepping debugging."), _("\
9102 When non-zero, displaced stepping specific debugging is enabled."),
9104 show_debug_displaced
,
9105 &setdebuglist
, &showdebuglist
);
9107 add_setshow_boolean_cmd ("non-stop", no_class
,
9109 Set whether gdb controls the inferior in non-stop mode."), _("\
9110 Show whether gdb controls the inferior in non-stop mode."), _("\
9111 When debugging a multi-threaded program and this setting is\n\
9112 off (the default, also called all-stop mode), when one thread stops\n\
9113 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9114 all other threads in the program while you interact with the thread of\n\
9115 interest. When you continue or step a thread, you can allow the other\n\
9116 threads to run, or have them remain stopped, but while you inspect any\n\
9117 thread's state, all threads stop.\n\
9119 In non-stop mode, when one thread stops, other threads can continue\n\
9120 to run freely. You'll be able to step each thread independently,\n\
9121 leave it stopped or free to run as needed."),
9127 numsigs
= (int) GDB_SIGNAL_LAST
;
9128 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9129 signal_print
= XNEWVEC (unsigned char, numsigs
);
9130 signal_program
= XNEWVEC (unsigned char, numsigs
);
9131 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9132 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9133 for (i
= 0; i
< numsigs
; i
++)
9136 signal_print
[i
] = 1;
9137 signal_program
[i
] = 1;
9138 signal_catch
[i
] = 0;
9141 /* Signals caused by debugger's own actions should not be given to
9142 the program afterwards.
9144 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9145 explicitly specifies that it should be delivered to the target
9146 program. Typically, that would occur when a user is debugging a
9147 target monitor on a simulator: the target monitor sets a
9148 breakpoint; the simulator encounters this breakpoint and halts
9149 the simulation handing control to GDB; GDB, noting that the stop
9150 address doesn't map to any known breakpoint, returns control back
9151 to the simulator; the simulator then delivers the hardware
9152 equivalent of a GDB_SIGNAL_TRAP to the program being
9154 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9155 signal_program
[GDB_SIGNAL_INT
] = 0;
9157 /* Signals that are not errors should not normally enter the debugger. */
9158 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9159 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9160 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9161 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9162 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9163 signal_print
[GDB_SIGNAL_PROF
] = 0;
9164 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9165 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9166 signal_stop
[GDB_SIGNAL_IO
] = 0;
9167 signal_print
[GDB_SIGNAL_IO
] = 0;
9168 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9169 signal_print
[GDB_SIGNAL_POLL
] = 0;
9170 signal_stop
[GDB_SIGNAL_URG
] = 0;
9171 signal_print
[GDB_SIGNAL_URG
] = 0;
9172 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9173 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9174 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9175 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9177 /* These signals are used internally by user-level thread
9178 implementations. (See signal(5) on Solaris.) Like the above
9179 signals, a healthy program receives and handles them as part of
9180 its normal operation. */
9181 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9182 signal_print
[GDB_SIGNAL_LWP
] = 0;
9183 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9184 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9185 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9186 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9188 /* Update cached state. */
9189 signal_cache_update (-1);
9191 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9192 &stop_on_solib_events
, _("\
9193 Set stopping for shared library events."), _("\
9194 Show stopping for shared library events."), _("\
9195 If nonzero, gdb will give control to the user when the dynamic linker\n\
9196 notifies gdb of shared library events. The most common event of interest\n\
9197 to the user would be loading/unloading of a new library."),
9198 set_stop_on_solib_events
,
9199 show_stop_on_solib_events
,
9200 &setlist
, &showlist
);
9202 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9203 follow_fork_mode_kind_names
,
9204 &follow_fork_mode_string
, _("\
9205 Set debugger response to a program call of fork or vfork."), _("\
9206 Show debugger response to a program call of fork or vfork."), _("\
9207 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9208 parent - the original process is debugged after a fork\n\
9209 child - the new process is debugged after a fork\n\
9210 The unfollowed process will continue to run.\n\
9211 By default, the debugger will follow the parent process."),
9213 show_follow_fork_mode_string
,
9214 &setlist
, &showlist
);
9216 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9217 follow_exec_mode_names
,
9218 &follow_exec_mode_string
, _("\
9219 Set debugger response to a program call of exec."), _("\
9220 Show debugger response to a program call of exec."), _("\
9221 An exec call replaces the program image of a process.\n\
9223 follow-exec-mode can be:\n\
9225 new - the debugger creates a new inferior and rebinds the process\n\
9226 to this new inferior. The program the process was running before\n\
9227 the exec call can be restarted afterwards by restarting the original\n\
9230 same - the debugger keeps the process bound to the same inferior.\n\
9231 The new executable image replaces the previous executable loaded in\n\
9232 the inferior. Restarting the inferior after the exec call restarts\n\
9233 the executable the process was running after the exec call.\n\
9235 By default, the debugger will use the same inferior."),
9237 show_follow_exec_mode_string
,
9238 &setlist
, &showlist
);
9240 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9241 scheduler_enums
, &scheduler_mode
, _("\
9242 Set mode for locking scheduler during execution."), _("\
9243 Show mode for locking scheduler during execution."), _("\
9244 off == no locking (threads may preempt at any time)\n\
9245 on == full locking (no thread except the current thread may run)\n\
9246 This applies to both normal execution and replay mode.\n\
9247 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9248 In this mode, other threads may run during other commands.\n\
9249 This applies to both normal execution and replay mode.\n\
9250 replay == scheduler locked in replay mode and unlocked during normal execution."),
9251 set_schedlock_func
, /* traps on target vector */
9252 show_scheduler_mode
,
9253 &setlist
, &showlist
);
9255 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9256 Set mode for resuming threads of all processes."), _("\
9257 Show mode for resuming threads of all processes."), _("\
9258 When on, execution commands (such as 'continue' or 'next') resume all\n\
9259 threads of all processes. When off (which is the default), execution\n\
9260 commands only resume the threads of the current process. The set of\n\
9261 threads that are resumed is further refined by the scheduler-locking\n\
9262 mode (see help set scheduler-locking)."),
9264 show_schedule_multiple
,
9265 &setlist
, &showlist
);
9267 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9268 Set mode of the step operation."), _("\
9269 Show mode of the step operation."), _("\
9270 When set, doing a step over a function without debug line information\n\
9271 will stop at the first instruction of that function. Otherwise, the\n\
9272 function is skipped and the step command stops at a different source line."),
9274 show_step_stop_if_no_debug
,
9275 &setlist
, &showlist
);
9277 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9278 &can_use_displaced_stepping
, _("\
9279 Set debugger's willingness to use displaced stepping."), _("\
9280 Show debugger's willingness to use displaced stepping."), _("\
9281 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9282 supported by the target architecture. If off, gdb will not use displaced\n\
9283 stepping to step over breakpoints, even if such is supported by the target\n\
9284 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9285 if the target architecture supports it and non-stop mode is active, but will not\n\
9286 use it in all-stop mode (see help set non-stop)."),
9288 show_can_use_displaced_stepping
,
9289 &setlist
, &showlist
);
9291 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9292 &exec_direction
, _("Set direction of execution.\n\
9293 Options are 'forward' or 'reverse'."),
9294 _("Show direction of execution (forward/reverse)."),
9295 _("Tells gdb whether to execute forward or backward."),
9296 set_exec_direction_func
, show_exec_direction_func
,
9297 &setlist
, &showlist
);
9299 /* Set/show detach-on-fork: user-settable mode. */
9301 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9302 Set whether gdb will detach the child of a fork."), _("\
9303 Show whether gdb will detach the child of a fork."), _("\
9304 Tells gdb whether to detach the child of a fork."),
9305 NULL
, NULL
, &setlist
, &showlist
);
9307 /* Set/show disable address space randomization mode. */
9309 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9310 &disable_randomization
, _("\
9311 Set disabling of debuggee's virtual address space randomization."), _("\
9312 Show disabling of debuggee's virtual address space randomization."), _("\
9313 When this mode is on (which is the default), randomization of the virtual\n\
9314 address space is disabled. Standalone programs run with the randomization\n\
9315 enabled by default on some platforms."),
9316 &set_disable_randomization
,
9317 &show_disable_randomization
,
9318 &setlist
, &showlist
);
9320 /* ptid initializations */
9321 inferior_ptid
= null_ptid
;
9322 target_last_wait_ptid
= minus_one_ptid
;
9324 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9325 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9326 observer_attach_thread_exit (infrun_thread_thread_exit
);
9327 observer_attach_inferior_exit (infrun_inferior_exit
);
9329 /* Explicitly create without lookup, since that tries to create a
9330 value with a void typed value, and when we get here, gdbarch
9331 isn't initialized yet. At this point, we're quite sure there
9332 isn't another convenience variable of the same name. */
9333 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9335 add_setshow_boolean_cmd ("observer", no_class
,
9336 &observer_mode_1
, _("\
9337 Set whether gdb controls the inferior in observer mode."), _("\
9338 Show whether gdb controls the inferior in observer mode."), _("\
9339 In observer mode, GDB can get data from the inferior, but not\n\
9340 affect its execution. Registers and memory may not be changed,\n\
9341 breakpoints may not be set, and the program cannot be interrupted\n\