1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2013 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 "exceptions.h"
28 #include "breakpoint.h"
32 #include "cli/cli-script.h"
34 #include "gdbthread.h"
46 #include "dictionary.h"
48 #include "gdb_assert.h"
49 #include "mi/mi-common.h"
50 #include "event-top.h"
52 #include "record-full.h"
53 #include "inline-frame.h"
55 #include "tracepoint.h"
56 #include "continuations.h"
61 #include "completer.h"
62 #include "target-descriptions.h"
64 /* Prototypes for local functions */
66 static void signals_info (char *, int);
68 static void handle_command (char *, int);
70 static void sig_print_info (enum gdb_signal
);
72 static void sig_print_header (void);
74 static void resume_cleanups (void *);
76 static int hook_stop_stub (void *);
78 static int restore_selected_frame (void *);
80 static int follow_fork (void);
82 static void set_schedlock_func (char *args
, int from_tty
,
83 struct cmd_list_element
*c
);
85 static int currently_stepping (struct thread_info
*tp
);
87 static int currently_stepping_or_nexting_callback (struct thread_info
*tp
,
90 static void xdb_handle_command (char *args
, int from_tty
);
92 static int prepare_to_proceed (int);
94 static void print_exited_reason (int exitstatus
);
96 static void print_signal_exited_reason (enum gdb_signal siggnal
);
98 static void print_no_history_reason (void);
100 static void print_signal_received_reason (enum gdb_signal siggnal
);
102 static void print_end_stepping_range_reason (void);
104 void _initialize_infrun (void);
106 void nullify_last_target_wait_ptid (void);
108 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
110 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
112 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
114 /* When set, stop the 'step' command if we enter a function which has
115 no line number information. The normal behavior is that we step
116 over such function. */
117 int step_stop_if_no_debug
= 0;
119 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
120 struct cmd_list_element
*c
, const char *value
)
122 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
125 /* In asynchronous mode, but simulating synchronous execution. */
127 int sync_execution
= 0;
129 /* wait_for_inferior and normal_stop use this to notify the user
130 when the inferior stopped in a different thread than it had been
133 static ptid_t previous_inferior_ptid
;
135 /* If set (default for legacy reasons), when following a fork, GDB
136 will detach from one of the fork branches, child or parent.
137 Exactly which branch is detached depends on 'set follow-fork-mode'
140 static int detach_fork
= 1;
142 int debug_displaced
= 0;
144 show_debug_displaced (struct ui_file
*file
, int from_tty
,
145 struct cmd_list_element
*c
, const char *value
)
147 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
150 unsigned int debug_infrun
= 0;
152 show_debug_infrun (struct ui_file
*file
, int from_tty
,
153 struct cmd_list_element
*c
, const char *value
)
155 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
159 /* Support for disabling address space randomization. */
161 int disable_randomization
= 1;
164 show_disable_randomization (struct ui_file
*file
, int from_tty
,
165 struct cmd_list_element
*c
, const char *value
)
167 if (target_supports_disable_randomization ())
168 fprintf_filtered (file
,
169 _("Disabling randomization of debuggee's "
170 "virtual address space is %s.\n"),
173 fputs_filtered (_("Disabling randomization of debuggee's "
174 "virtual address space is unsupported on\n"
175 "this platform.\n"), file
);
179 set_disable_randomization (char *args
, int from_tty
,
180 struct cmd_list_element
*c
)
182 if (!target_supports_disable_randomization ())
183 error (_("Disabling randomization of debuggee's "
184 "virtual address space is unsupported on\n"
188 /* User interface for non-stop mode. */
191 static int non_stop_1
= 0;
194 set_non_stop (char *args
, int from_tty
,
195 struct cmd_list_element
*c
)
197 if (target_has_execution
)
199 non_stop_1
= non_stop
;
200 error (_("Cannot change this setting while the inferior is running."));
203 non_stop
= non_stop_1
;
207 show_non_stop (struct ui_file
*file
, int from_tty
,
208 struct cmd_list_element
*c
, const char *value
)
210 fprintf_filtered (file
,
211 _("Controlling the inferior in non-stop mode is %s.\n"),
215 /* "Observer mode" is somewhat like a more extreme version of
216 non-stop, in which all GDB operations that might affect the
217 target's execution have been disabled. */
219 int observer_mode
= 0;
220 static int observer_mode_1
= 0;
223 set_observer_mode (char *args
, int from_tty
,
224 struct cmd_list_element
*c
)
226 if (target_has_execution
)
228 observer_mode_1
= observer_mode
;
229 error (_("Cannot change this setting while the inferior is running."));
232 observer_mode
= observer_mode_1
;
234 may_write_registers
= !observer_mode
;
235 may_write_memory
= !observer_mode
;
236 may_insert_breakpoints
= !observer_mode
;
237 may_insert_tracepoints
= !observer_mode
;
238 /* We can insert fast tracepoints in or out of observer mode,
239 but enable them if we're going into this mode. */
241 may_insert_fast_tracepoints
= 1;
242 may_stop
= !observer_mode
;
243 update_target_permissions ();
245 /* Going *into* observer mode we must force non-stop, then
246 going out we leave it that way. */
249 target_async_permitted
= 1;
250 pagination_enabled
= 0;
251 non_stop
= non_stop_1
= 1;
255 printf_filtered (_("Observer mode is now %s.\n"),
256 (observer_mode
? "on" : "off"));
260 show_observer_mode (struct ui_file
*file
, int from_tty
,
261 struct cmd_list_element
*c
, const char *value
)
263 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
266 /* This updates the value of observer mode based on changes in
267 permissions. Note that we are deliberately ignoring the values of
268 may-write-registers and may-write-memory, since the user may have
269 reason to enable these during a session, for instance to turn on a
270 debugging-related global. */
273 update_observer_mode (void)
277 newval
= (!may_insert_breakpoints
278 && !may_insert_tracepoints
279 && may_insert_fast_tracepoints
283 /* Let the user know if things change. */
284 if (newval
!= observer_mode
)
285 printf_filtered (_("Observer mode is now %s.\n"),
286 (newval
? "on" : "off"));
288 observer_mode
= observer_mode_1
= newval
;
291 /* Tables of how to react to signals; the user sets them. */
293 static unsigned char *signal_stop
;
294 static unsigned char *signal_print
;
295 static unsigned char *signal_program
;
297 /* Table of signals that are registered with "catch signal". A
298 non-zero entry indicates that the signal is caught by some "catch
299 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
301 static unsigned char *signal_catch
;
303 /* Table of signals that the target may silently handle.
304 This is automatically determined from the flags above,
305 and simply cached here. */
306 static unsigned char *signal_pass
;
308 #define SET_SIGS(nsigs,sigs,flags) \
310 int signum = (nsigs); \
311 while (signum-- > 0) \
312 if ((sigs)[signum]) \
313 (flags)[signum] = 1; \
316 #define UNSET_SIGS(nsigs,sigs,flags) \
318 int signum = (nsigs); \
319 while (signum-- > 0) \
320 if ((sigs)[signum]) \
321 (flags)[signum] = 0; \
324 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
325 this function is to avoid exporting `signal_program'. */
328 update_signals_program_target (void)
330 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
333 /* Value to pass to target_resume() to cause all threads to resume. */
335 #define RESUME_ALL minus_one_ptid
337 /* Command list pointer for the "stop" placeholder. */
339 static struct cmd_list_element
*stop_command
;
341 /* Function inferior was in as of last step command. */
343 static struct symbol
*step_start_function
;
345 /* Nonzero if we want to give control to the user when we're notified
346 of shared library events by the dynamic linker. */
347 int stop_on_solib_events
;
349 /* Enable or disable optional shared library event breakpoints
350 as appropriate when the above flag is changed. */
353 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
355 update_solib_breakpoints ();
359 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
360 struct cmd_list_element
*c
, const char *value
)
362 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
366 /* Nonzero means expecting a trace trap
367 and should stop the inferior and return silently when it happens. */
371 /* Save register contents here when executing a "finish" command or are
372 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
373 Thus this contains the return value from the called function (assuming
374 values are returned in a register). */
376 struct regcache
*stop_registers
;
378 /* Nonzero after stop if current stack frame should be printed. */
380 static int stop_print_frame
;
382 /* This is a cached copy of the pid/waitstatus of the last event
383 returned by target_wait()/deprecated_target_wait_hook(). This
384 information is returned by get_last_target_status(). */
385 static ptid_t target_last_wait_ptid
;
386 static struct target_waitstatus target_last_waitstatus
;
388 static void context_switch (ptid_t ptid
);
390 void init_thread_stepping_state (struct thread_info
*tss
);
392 static void init_infwait_state (void);
394 static const char follow_fork_mode_child
[] = "child";
395 static const char follow_fork_mode_parent
[] = "parent";
397 static const char *const follow_fork_mode_kind_names
[] = {
398 follow_fork_mode_child
,
399 follow_fork_mode_parent
,
403 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
405 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
406 struct cmd_list_element
*c
, const char *value
)
408 fprintf_filtered (file
,
409 _("Debugger response to a program "
410 "call of fork or vfork is \"%s\".\n"),
415 /* Tell the target to follow the fork we're stopped at. Returns true
416 if the inferior should be resumed; false, if the target for some
417 reason decided it's best not to resume. */
422 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
423 int should_resume
= 1;
424 struct thread_info
*tp
;
426 /* Copy user stepping state to the new inferior thread. FIXME: the
427 followed fork child thread should have a copy of most of the
428 parent thread structure's run control related fields, not just these.
429 Initialized to avoid "may be used uninitialized" warnings from gcc. */
430 struct breakpoint
*step_resume_breakpoint
= NULL
;
431 struct breakpoint
*exception_resume_breakpoint
= NULL
;
432 CORE_ADDR step_range_start
= 0;
433 CORE_ADDR step_range_end
= 0;
434 struct frame_id step_frame_id
= { 0 };
439 struct target_waitstatus wait_status
;
441 /* Get the last target status returned by target_wait(). */
442 get_last_target_status (&wait_ptid
, &wait_status
);
444 /* If not stopped at a fork event, then there's nothing else to
446 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
447 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
450 /* Check if we switched over from WAIT_PTID, since the event was
452 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
453 && !ptid_equal (inferior_ptid
, wait_ptid
))
455 /* We did. Switch back to WAIT_PTID thread, to tell the
456 target to follow it (in either direction). We'll
457 afterwards refuse to resume, and inform the user what
459 switch_to_thread (wait_ptid
);
464 tp
= inferior_thread ();
466 /* If there were any forks/vforks that were caught and are now to be
467 followed, then do so now. */
468 switch (tp
->pending_follow
.kind
)
470 case TARGET_WAITKIND_FORKED
:
471 case TARGET_WAITKIND_VFORKED
:
473 ptid_t parent
, child
;
475 /* If the user did a next/step, etc, over a fork call,
476 preserve the stepping state in the fork child. */
477 if (follow_child
&& should_resume
)
479 step_resume_breakpoint
= clone_momentary_breakpoint
480 (tp
->control
.step_resume_breakpoint
);
481 step_range_start
= tp
->control
.step_range_start
;
482 step_range_end
= tp
->control
.step_range_end
;
483 step_frame_id
= tp
->control
.step_frame_id
;
484 exception_resume_breakpoint
485 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
487 /* For now, delete the parent's sr breakpoint, otherwise,
488 parent/child sr breakpoints are considered duplicates,
489 and the child version will not be installed. Remove
490 this when the breakpoints module becomes aware of
491 inferiors and address spaces. */
492 delete_step_resume_breakpoint (tp
);
493 tp
->control
.step_range_start
= 0;
494 tp
->control
.step_range_end
= 0;
495 tp
->control
.step_frame_id
= null_frame_id
;
496 delete_exception_resume_breakpoint (tp
);
499 parent
= inferior_ptid
;
500 child
= tp
->pending_follow
.value
.related_pid
;
502 /* Tell the target to do whatever is necessary to follow
503 either parent or child. */
504 if (target_follow_fork (follow_child
, detach_fork
))
506 /* Target refused to follow, or there's some other reason
507 we shouldn't resume. */
512 /* This pending follow fork event is now handled, one way
513 or another. The previous selected thread may be gone
514 from the lists by now, but if it is still around, need
515 to clear the pending follow request. */
516 tp
= find_thread_ptid (parent
);
518 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
520 /* This makes sure we don't try to apply the "Switched
521 over from WAIT_PID" logic above. */
522 nullify_last_target_wait_ptid ();
524 /* If we followed the child, switch to it... */
527 switch_to_thread (child
);
529 /* ... and preserve the stepping state, in case the
530 user was stepping over the fork call. */
533 tp
= inferior_thread ();
534 tp
->control
.step_resume_breakpoint
535 = step_resume_breakpoint
;
536 tp
->control
.step_range_start
= step_range_start
;
537 tp
->control
.step_range_end
= step_range_end
;
538 tp
->control
.step_frame_id
= step_frame_id
;
539 tp
->control
.exception_resume_breakpoint
540 = exception_resume_breakpoint
;
544 /* If we get here, it was because we're trying to
545 resume from a fork catchpoint, but, the user
546 has switched threads away from the thread that
547 forked. In that case, the resume command
548 issued is most likely not applicable to the
549 child, so just warn, and refuse to resume. */
550 warning (_("Not resuming: switched threads "
551 "before following fork child.\n"));
554 /* Reset breakpoints in the child as appropriate. */
555 follow_inferior_reset_breakpoints ();
558 switch_to_thread (parent
);
562 case TARGET_WAITKIND_SPURIOUS
:
563 /* Nothing to follow. */
566 internal_error (__FILE__
, __LINE__
,
567 "Unexpected pending_follow.kind %d\n",
568 tp
->pending_follow
.kind
);
572 return should_resume
;
576 follow_inferior_reset_breakpoints (void)
578 struct thread_info
*tp
= inferior_thread ();
580 /* Was there a step_resume breakpoint? (There was if the user
581 did a "next" at the fork() call.) If so, explicitly reset its
584 step_resumes are a form of bp that are made to be per-thread.
585 Since we created the step_resume bp when the parent process
586 was being debugged, and now are switching to the child process,
587 from the breakpoint package's viewpoint, that's a switch of
588 "threads". We must update the bp's notion of which thread
589 it is for, or it'll be ignored when it triggers. */
591 if (tp
->control
.step_resume_breakpoint
)
592 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
594 if (tp
->control
.exception_resume_breakpoint
)
595 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
597 /* Reinsert all breakpoints in the child. The user may have set
598 breakpoints after catching the fork, in which case those
599 were never set in the child, but only in the parent. This makes
600 sure the inserted breakpoints match the breakpoint list. */
602 breakpoint_re_set ();
603 insert_breakpoints ();
606 /* The child has exited or execed: resume threads of the parent the
607 user wanted to be executing. */
610 proceed_after_vfork_done (struct thread_info
*thread
,
613 int pid
= * (int *) arg
;
615 if (ptid_get_pid (thread
->ptid
) == pid
616 && is_running (thread
->ptid
)
617 && !is_executing (thread
->ptid
)
618 && !thread
->stop_requested
619 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
622 fprintf_unfiltered (gdb_stdlog
,
623 "infrun: resuming vfork parent thread %s\n",
624 target_pid_to_str (thread
->ptid
));
626 switch_to_thread (thread
->ptid
);
627 clear_proceed_status ();
628 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
, 0);
634 /* Called whenever we notice an exec or exit event, to handle
635 detaching or resuming a vfork parent. */
638 handle_vfork_child_exec_or_exit (int exec
)
640 struct inferior
*inf
= current_inferior ();
642 if (inf
->vfork_parent
)
644 int resume_parent
= -1;
646 /* This exec or exit marks the end of the shared memory region
647 between the parent and the child. If the user wanted to
648 detach from the parent, now is the time. */
650 if (inf
->vfork_parent
->pending_detach
)
652 struct thread_info
*tp
;
653 struct cleanup
*old_chain
;
654 struct program_space
*pspace
;
655 struct address_space
*aspace
;
657 /* follow-fork child, detach-on-fork on. */
659 inf
->vfork_parent
->pending_detach
= 0;
663 /* If we're handling a child exit, then inferior_ptid
664 points at the inferior's pid, not to a thread. */
665 old_chain
= save_inferior_ptid ();
666 save_current_program_space ();
667 save_current_inferior ();
670 old_chain
= save_current_space_and_thread ();
672 /* We're letting loose of the parent. */
673 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
674 switch_to_thread (tp
->ptid
);
676 /* We're about to detach from the parent, which implicitly
677 removes breakpoints from its address space. There's a
678 catch here: we want to reuse the spaces for the child,
679 but, parent/child are still sharing the pspace at this
680 point, although the exec in reality makes the kernel give
681 the child a fresh set of new pages. The problem here is
682 that the breakpoints module being unaware of this, would
683 likely chose the child process to write to the parent
684 address space. Swapping the child temporarily away from
685 the spaces has the desired effect. Yes, this is "sort
688 pspace
= inf
->pspace
;
689 aspace
= inf
->aspace
;
693 if (debug_infrun
|| info_verbose
)
695 target_terminal_ours ();
698 fprintf_filtered (gdb_stdlog
,
699 "Detaching vfork parent process "
700 "%d after child exec.\n",
701 inf
->vfork_parent
->pid
);
703 fprintf_filtered (gdb_stdlog
,
704 "Detaching vfork parent process "
705 "%d after child exit.\n",
706 inf
->vfork_parent
->pid
);
709 target_detach (NULL
, 0);
712 inf
->pspace
= pspace
;
713 inf
->aspace
= aspace
;
715 do_cleanups (old_chain
);
719 /* We're staying attached to the parent, so, really give the
720 child a new address space. */
721 inf
->pspace
= add_program_space (maybe_new_address_space ());
722 inf
->aspace
= inf
->pspace
->aspace
;
724 set_current_program_space (inf
->pspace
);
726 resume_parent
= inf
->vfork_parent
->pid
;
728 /* Break the bonds. */
729 inf
->vfork_parent
->vfork_child
= NULL
;
733 struct cleanup
*old_chain
;
734 struct program_space
*pspace
;
736 /* If this is a vfork child exiting, then the pspace and
737 aspaces were shared with the parent. Since we're
738 reporting the process exit, we'll be mourning all that is
739 found in the address space, and switching to null_ptid,
740 preparing to start a new inferior. But, since we don't
741 want to clobber the parent's address/program spaces, we
742 go ahead and create a new one for this exiting
745 /* Switch to null_ptid, so that clone_program_space doesn't want
746 to read the selected frame of a dead process. */
747 old_chain
= save_inferior_ptid ();
748 inferior_ptid
= null_ptid
;
750 /* This inferior is dead, so avoid giving the breakpoints
751 module the option to write through to it (cloning a
752 program space resets breakpoints). */
755 pspace
= add_program_space (maybe_new_address_space ());
756 set_current_program_space (pspace
);
758 inf
->symfile_flags
= SYMFILE_NO_READ
;
759 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
760 inf
->pspace
= pspace
;
761 inf
->aspace
= pspace
->aspace
;
763 /* Put back inferior_ptid. We'll continue mourning this
765 do_cleanups (old_chain
);
767 resume_parent
= inf
->vfork_parent
->pid
;
768 /* Break the bonds. */
769 inf
->vfork_parent
->vfork_child
= NULL
;
772 inf
->vfork_parent
= NULL
;
774 gdb_assert (current_program_space
== inf
->pspace
);
776 if (non_stop
&& resume_parent
!= -1)
778 /* If the user wanted the parent to be running, let it go
780 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
783 fprintf_unfiltered (gdb_stdlog
,
784 "infrun: resuming vfork parent process %d\n",
787 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
789 do_cleanups (old_chain
);
794 /* Enum strings for "set|show follow-exec-mode". */
796 static const char follow_exec_mode_new
[] = "new";
797 static const char follow_exec_mode_same
[] = "same";
798 static const char *const follow_exec_mode_names
[] =
800 follow_exec_mode_new
,
801 follow_exec_mode_same
,
805 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
807 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
808 struct cmd_list_element
*c
, const char *value
)
810 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
813 /* EXECD_PATHNAME is assumed to be non-NULL. */
816 follow_exec (ptid_t pid
, char *execd_pathname
)
818 struct thread_info
*th
= inferior_thread ();
819 struct inferior
*inf
= current_inferior ();
821 /* This is an exec event that we actually wish to pay attention to.
822 Refresh our symbol table to the newly exec'd program, remove any
825 If there are breakpoints, they aren't really inserted now,
826 since the exec() transformed our inferior into a fresh set
829 We want to preserve symbolic breakpoints on the list, since
830 we have hopes that they can be reset after the new a.out's
831 symbol table is read.
833 However, any "raw" breakpoints must be removed from the list
834 (e.g., the solib bp's), since their address is probably invalid
837 And, we DON'T want to call delete_breakpoints() here, since
838 that may write the bp's "shadow contents" (the instruction
839 value that was overwritten witha TRAP instruction). Since
840 we now have a new a.out, those shadow contents aren't valid. */
842 mark_breakpoints_out ();
844 update_breakpoints_after_exec ();
846 /* If there was one, it's gone now. We cannot truly step-to-next
847 statement through an exec(). */
848 th
->control
.step_resume_breakpoint
= NULL
;
849 th
->control
.exception_resume_breakpoint
= NULL
;
850 th
->control
.step_range_start
= 0;
851 th
->control
.step_range_end
= 0;
853 /* The target reports the exec event to the main thread, even if
854 some other thread does the exec, and even if the main thread was
855 already stopped --- if debugging in non-stop mode, it's possible
856 the user had the main thread held stopped in the previous image
857 --- release it now. This is the same behavior as step-over-exec
858 with scheduler-locking on in all-stop mode. */
859 th
->stop_requested
= 0;
861 /* What is this a.out's name? */
862 printf_unfiltered (_("%s is executing new program: %s\n"),
863 target_pid_to_str (inferior_ptid
),
866 /* We've followed the inferior through an exec. Therefore, the
867 inferior has essentially been killed & reborn. */
869 gdb_flush (gdb_stdout
);
871 breakpoint_init_inferior (inf_execd
);
873 if (gdb_sysroot
&& *gdb_sysroot
)
875 char *name
= alloca (strlen (gdb_sysroot
)
876 + strlen (execd_pathname
)
879 strcpy (name
, gdb_sysroot
);
880 strcat (name
, execd_pathname
);
881 execd_pathname
= name
;
884 /* Reset the shared library package. This ensures that we get a
885 shlib event when the child reaches "_start", at which point the
886 dld will have had a chance to initialize the child. */
887 /* Also, loading a symbol file below may trigger symbol lookups, and
888 we don't want those to be satisfied by the libraries of the
889 previous incarnation of this process. */
890 no_shared_libraries (NULL
, 0);
892 if (follow_exec_mode_string
== follow_exec_mode_new
)
894 struct program_space
*pspace
;
896 /* The user wants to keep the old inferior and program spaces
897 around. Create a new fresh one, and switch to it. */
899 inf
= add_inferior (current_inferior ()->pid
);
900 pspace
= add_program_space (maybe_new_address_space ());
901 inf
->pspace
= pspace
;
902 inf
->aspace
= pspace
->aspace
;
904 exit_inferior_num_silent (current_inferior ()->num
);
906 set_current_inferior (inf
);
907 set_current_program_space (pspace
);
911 /* The old description may no longer be fit for the new image.
912 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
913 old description; we'll read a new one below. No need to do
914 this on "follow-exec-mode new", as the old inferior stays
915 around (its description is later cleared/refetched on
917 target_clear_description ();
920 gdb_assert (current_program_space
== inf
->pspace
);
922 /* That a.out is now the one to use. */
923 exec_file_attach (execd_pathname
, 0);
925 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
926 (Position Independent Executable) main symbol file will get applied by
927 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
928 the breakpoints with the zero displacement. */
930 symbol_file_add (execd_pathname
,
932 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
935 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
936 set_initial_language ();
938 /* If the target can specify a description, read it. Must do this
939 after flipping to the new executable (because the target supplied
940 description must be compatible with the executable's
941 architecture, and the old executable may e.g., be 32-bit, while
942 the new one 64-bit), and before anything involving memory or
944 target_find_description ();
946 solib_create_inferior_hook (0);
948 jit_inferior_created_hook ();
950 breakpoint_re_set ();
952 /* Reinsert all breakpoints. (Those which were symbolic have
953 been reset to the proper address in the new a.out, thanks
954 to symbol_file_command...). */
955 insert_breakpoints ();
957 /* The next resume of this inferior should bring it to the shlib
958 startup breakpoints. (If the user had also set bp's on
959 "main" from the old (parent) process, then they'll auto-
960 matically get reset there in the new process.). */
963 /* Non-zero if we just simulating a single-step. This is needed
964 because we cannot remove the breakpoints in the inferior process
965 until after the `wait' in `wait_for_inferior'. */
966 static int singlestep_breakpoints_inserted_p
= 0;
968 /* The thread we inserted single-step breakpoints for. */
969 static ptid_t singlestep_ptid
;
971 /* PC when we started this single-step. */
972 static CORE_ADDR singlestep_pc
;
974 /* If another thread hit the singlestep breakpoint, we save the original
975 thread here so that we can resume single-stepping it later. */
976 static ptid_t saved_singlestep_ptid
;
977 static int stepping_past_singlestep_breakpoint
;
979 /* If not equal to null_ptid, this means that after stepping over breakpoint
980 is finished, we need to switch to deferred_step_ptid, and step it.
982 The use case is when one thread has hit a breakpoint, and then the user
983 has switched to another thread and issued 'step'. We need to step over
984 breakpoint in the thread which hit the breakpoint, but then continue
985 stepping the thread user has selected. */
986 static ptid_t deferred_step_ptid
;
988 /* Displaced stepping. */
990 /* In non-stop debugging mode, we must take special care to manage
991 breakpoints properly; in particular, the traditional strategy for
992 stepping a thread past a breakpoint it has hit is unsuitable.
993 'Displaced stepping' is a tactic for stepping one thread past a
994 breakpoint it has hit while ensuring that other threads running
995 concurrently will hit the breakpoint as they should.
997 The traditional way to step a thread T off a breakpoint in a
998 multi-threaded program in all-stop mode is as follows:
1000 a0) Initially, all threads are stopped, and breakpoints are not
1002 a1) We single-step T, leaving breakpoints uninserted.
1003 a2) We insert breakpoints, and resume all threads.
1005 In non-stop debugging, however, this strategy is unsuitable: we
1006 don't want to have to stop all threads in the system in order to
1007 continue or step T past a breakpoint. Instead, we use displaced
1010 n0) Initially, T is stopped, other threads are running, and
1011 breakpoints are inserted.
1012 n1) We copy the instruction "under" the breakpoint to a separate
1013 location, outside the main code stream, making any adjustments
1014 to the instruction, register, and memory state as directed by
1016 n2) We single-step T over the instruction at its new location.
1017 n3) We adjust the resulting register and memory state as directed
1018 by T's architecture. This includes resetting T's PC to point
1019 back into the main instruction stream.
1022 This approach depends on the following gdbarch methods:
1024 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1025 indicate where to copy the instruction, and how much space must
1026 be reserved there. We use these in step n1.
1028 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1029 address, and makes any necessary adjustments to the instruction,
1030 register contents, and memory. We use this in step n1.
1032 - gdbarch_displaced_step_fixup adjusts registers and memory after
1033 we have successfuly single-stepped the instruction, to yield the
1034 same effect the instruction would have had if we had executed it
1035 at its original address. We use this in step n3.
1037 - gdbarch_displaced_step_free_closure provides cleanup.
1039 The gdbarch_displaced_step_copy_insn and
1040 gdbarch_displaced_step_fixup functions must be written so that
1041 copying an instruction with gdbarch_displaced_step_copy_insn,
1042 single-stepping across the copied instruction, and then applying
1043 gdbarch_displaced_insn_fixup should have the same effects on the
1044 thread's memory and registers as stepping the instruction in place
1045 would have. Exactly which responsibilities fall to the copy and
1046 which fall to the fixup is up to the author of those functions.
1048 See the comments in gdbarch.sh for details.
1050 Note that displaced stepping and software single-step cannot
1051 currently be used in combination, although with some care I think
1052 they could be made to. Software single-step works by placing
1053 breakpoints on all possible subsequent instructions; if the
1054 displaced instruction is a PC-relative jump, those breakpoints
1055 could fall in very strange places --- on pages that aren't
1056 executable, or at addresses that are not proper instruction
1057 boundaries. (We do generally let other threads run while we wait
1058 to hit the software single-step breakpoint, and they might
1059 encounter such a corrupted instruction.) One way to work around
1060 this would be to have gdbarch_displaced_step_copy_insn fully
1061 simulate the effect of PC-relative instructions (and return NULL)
1062 on architectures that use software single-stepping.
1064 In non-stop mode, we can have independent and simultaneous step
1065 requests, so more than one thread may need to simultaneously step
1066 over a breakpoint. The current implementation assumes there is
1067 only one scratch space per process. In this case, we have to
1068 serialize access to the scratch space. If thread A wants to step
1069 over a breakpoint, but we are currently waiting for some other
1070 thread to complete a displaced step, we leave thread A stopped and
1071 place it in the displaced_step_request_queue. Whenever a displaced
1072 step finishes, we pick the next thread in the queue and start a new
1073 displaced step operation on it. See displaced_step_prepare and
1074 displaced_step_fixup for details. */
1076 struct displaced_step_request
1079 struct displaced_step_request
*next
;
1082 /* Per-inferior displaced stepping state. */
1083 struct displaced_step_inferior_state
1085 /* Pointer to next in linked list. */
1086 struct displaced_step_inferior_state
*next
;
1088 /* The process this displaced step state refers to. */
1091 /* A queue of pending displaced stepping requests. One entry per
1092 thread that needs to do a displaced step. */
1093 struct displaced_step_request
*step_request_queue
;
1095 /* If this is not null_ptid, this is the thread carrying out a
1096 displaced single-step in process PID. This thread's state will
1097 require fixing up once it has completed its step. */
1100 /* The architecture the thread had when we stepped it. */
1101 struct gdbarch
*step_gdbarch
;
1103 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1104 for post-step cleanup. */
1105 struct displaced_step_closure
*step_closure
;
1107 /* The address of the original instruction, and the copy we
1109 CORE_ADDR step_original
, step_copy
;
1111 /* Saved contents of copy area. */
1112 gdb_byte
*step_saved_copy
;
1115 /* The list of states of processes involved in displaced stepping
1117 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1119 /* Get the displaced stepping state of process PID. */
1121 static struct displaced_step_inferior_state
*
1122 get_displaced_stepping_state (int pid
)
1124 struct displaced_step_inferior_state
*state
;
1126 for (state
= displaced_step_inferior_states
;
1128 state
= state
->next
)
1129 if (state
->pid
== pid
)
1135 /* Add a new displaced stepping state for process PID to the displaced
1136 stepping state list, or return a pointer to an already existing
1137 entry, if it already exists. Never returns NULL. */
1139 static struct displaced_step_inferior_state
*
1140 add_displaced_stepping_state (int pid
)
1142 struct displaced_step_inferior_state
*state
;
1144 for (state
= displaced_step_inferior_states
;
1146 state
= state
->next
)
1147 if (state
->pid
== pid
)
1150 state
= xcalloc (1, sizeof (*state
));
1152 state
->next
= displaced_step_inferior_states
;
1153 displaced_step_inferior_states
= state
;
1158 /* If inferior is in displaced stepping, and ADDR equals to starting address
1159 of copy area, return corresponding displaced_step_closure. Otherwise,
1162 struct displaced_step_closure
*
1163 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1165 struct displaced_step_inferior_state
*displaced
1166 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1168 /* If checking the mode of displaced instruction in copy area. */
1169 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1170 && (displaced
->step_copy
== addr
))
1171 return displaced
->step_closure
;
1176 /* Remove the displaced stepping state of process PID. */
1179 remove_displaced_stepping_state (int pid
)
1181 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1183 gdb_assert (pid
!= 0);
1185 it
= displaced_step_inferior_states
;
1186 prev_next_p
= &displaced_step_inferior_states
;
1191 *prev_next_p
= it
->next
;
1196 prev_next_p
= &it
->next
;
1202 infrun_inferior_exit (struct inferior
*inf
)
1204 remove_displaced_stepping_state (inf
->pid
);
1207 /* If ON, and the architecture supports it, GDB will use displaced
1208 stepping to step over breakpoints. If OFF, or if the architecture
1209 doesn't support it, GDB will instead use the traditional
1210 hold-and-step approach. If AUTO (which is the default), GDB will
1211 decide which technique to use to step over breakpoints depending on
1212 which of all-stop or non-stop mode is active --- displaced stepping
1213 in non-stop mode; hold-and-step in all-stop mode. */
1215 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1218 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1219 struct cmd_list_element
*c
,
1222 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1223 fprintf_filtered (file
,
1224 _("Debugger's willingness to use displaced stepping "
1225 "to step over breakpoints is %s (currently %s).\n"),
1226 value
, non_stop
? "on" : "off");
1228 fprintf_filtered (file
,
1229 _("Debugger's willingness to use displaced stepping "
1230 "to step over breakpoints is %s.\n"), value
);
1233 /* Return non-zero if displaced stepping can/should be used to step
1234 over breakpoints. */
1237 use_displaced_stepping (struct gdbarch
*gdbarch
)
1239 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
&& non_stop
)
1240 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1241 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1242 && !RECORD_IS_USED
);
1245 /* Clean out any stray displaced stepping state. */
1247 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1249 /* Indicate that there is no cleanup pending. */
1250 displaced
->step_ptid
= null_ptid
;
1252 if (displaced
->step_closure
)
1254 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1255 displaced
->step_closure
);
1256 displaced
->step_closure
= NULL
;
1261 displaced_step_clear_cleanup (void *arg
)
1263 struct displaced_step_inferior_state
*state
= arg
;
1265 displaced_step_clear (state
);
1268 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1270 displaced_step_dump_bytes (struct ui_file
*file
,
1271 const gdb_byte
*buf
,
1276 for (i
= 0; i
< len
; i
++)
1277 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1278 fputs_unfiltered ("\n", file
);
1281 /* Prepare to single-step, using displaced stepping.
1283 Note that we cannot use displaced stepping when we have a signal to
1284 deliver. If we have a signal to deliver and an instruction to step
1285 over, then after the step, there will be no indication from the
1286 target whether the thread entered a signal handler or ignored the
1287 signal and stepped over the instruction successfully --- both cases
1288 result in a simple SIGTRAP. In the first case we mustn't do a
1289 fixup, and in the second case we must --- but we can't tell which.
1290 Comments in the code for 'random signals' in handle_inferior_event
1291 explain how we handle this case instead.
1293 Returns 1 if preparing was successful -- this thread is going to be
1294 stepped now; or 0 if displaced stepping this thread got queued. */
1296 displaced_step_prepare (ptid_t ptid
)
1298 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1299 struct thread_info
*tp
= find_thread_ptid (ptid
);
1300 struct regcache
*regcache
= get_thread_regcache (ptid
);
1301 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1302 CORE_ADDR original
, copy
;
1304 struct displaced_step_closure
*closure
;
1305 struct displaced_step_inferior_state
*displaced
;
1308 /* We should never reach this function if the architecture does not
1309 support displaced stepping. */
1310 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1312 /* Disable range stepping while executing in the scratch pad. We
1313 want a single-step even if executing the displaced instruction in
1314 the scratch buffer lands within the stepping range (e.g., a
1316 tp
->control
.may_range_step
= 0;
1318 /* We have to displaced step one thread at a time, as we only have
1319 access to a single scratch space per inferior. */
1321 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1323 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1325 /* Already waiting for a displaced step to finish. Defer this
1326 request and place in queue. */
1327 struct displaced_step_request
*req
, *new_req
;
1329 if (debug_displaced
)
1330 fprintf_unfiltered (gdb_stdlog
,
1331 "displaced: defering step of %s\n",
1332 target_pid_to_str (ptid
));
1334 new_req
= xmalloc (sizeof (*new_req
));
1335 new_req
->ptid
= ptid
;
1336 new_req
->next
= NULL
;
1338 if (displaced
->step_request_queue
)
1340 for (req
= displaced
->step_request_queue
;
1344 req
->next
= new_req
;
1347 displaced
->step_request_queue
= new_req
;
1353 if (debug_displaced
)
1354 fprintf_unfiltered (gdb_stdlog
,
1355 "displaced: stepping %s now\n",
1356 target_pid_to_str (ptid
));
1359 displaced_step_clear (displaced
);
1361 old_cleanups
= save_inferior_ptid ();
1362 inferior_ptid
= ptid
;
1364 original
= regcache_read_pc (regcache
);
1366 copy
= gdbarch_displaced_step_location (gdbarch
);
1367 len
= gdbarch_max_insn_length (gdbarch
);
1369 /* Save the original contents of the copy area. */
1370 displaced
->step_saved_copy
= xmalloc (len
);
1371 ignore_cleanups
= make_cleanup (free_current_contents
,
1372 &displaced
->step_saved_copy
);
1373 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1375 throw_error (MEMORY_ERROR
,
1376 _("Error accessing memory address %s (%s) for "
1377 "displaced-stepping scratch space."),
1378 paddress (gdbarch
, copy
), safe_strerror (status
));
1379 if (debug_displaced
)
1381 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1382 paddress (gdbarch
, copy
));
1383 displaced_step_dump_bytes (gdb_stdlog
,
1384 displaced
->step_saved_copy
,
1388 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1389 original
, copy
, regcache
);
1391 /* We don't support the fully-simulated case at present. */
1392 gdb_assert (closure
);
1394 /* Save the information we need to fix things up if the step
1396 displaced
->step_ptid
= ptid
;
1397 displaced
->step_gdbarch
= gdbarch
;
1398 displaced
->step_closure
= closure
;
1399 displaced
->step_original
= original
;
1400 displaced
->step_copy
= copy
;
1402 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1404 /* Resume execution at the copy. */
1405 regcache_write_pc (regcache
, copy
);
1407 discard_cleanups (ignore_cleanups
);
1409 do_cleanups (old_cleanups
);
1411 if (debug_displaced
)
1412 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1413 paddress (gdbarch
, copy
));
1419 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1420 const gdb_byte
*myaddr
, int len
)
1422 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1424 inferior_ptid
= ptid
;
1425 write_memory (memaddr
, myaddr
, len
);
1426 do_cleanups (ptid_cleanup
);
1429 /* Restore the contents of the copy area for thread PTID. */
1432 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1435 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1437 write_memory_ptid (ptid
, displaced
->step_copy
,
1438 displaced
->step_saved_copy
, len
);
1439 if (debug_displaced
)
1440 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1441 target_pid_to_str (ptid
),
1442 paddress (displaced
->step_gdbarch
,
1443 displaced
->step_copy
));
1447 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1449 struct cleanup
*old_cleanups
;
1450 struct displaced_step_inferior_state
*displaced
1451 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1453 /* Was any thread of this process doing a displaced step? */
1454 if (displaced
== NULL
)
1457 /* Was this event for the pid we displaced? */
1458 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1459 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1462 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1464 displaced_step_restore (displaced
, displaced
->step_ptid
);
1466 /* Did the instruction complete successfully? */
1467 if (signal
== GDB_SIGNAL_TRAP
)
1469 /* Fix up the resulting state. */
1470 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1471 displaced
->step_closure
,
1472 displaced
->step_original
,
1473 displaced
->step_copy
,
1474 get_thread_regcache (displaced
->step_ptid
));
1478 /* Since the instruction didn't complete, all we can do is
1480 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1481 CORE_ADDR pc
= regcache_read_pc (regcache
);
1483 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1484 regcache_write_pc (regcache
, pc
);
1487 do_cleanups (old_cleanups
);
1489 displaced
->step_ptid
= null_ptid
;
1491 /* Are there any pending displaced stepping requests? If so, run
1492 one now. Leave the state object around, since we're likely to
1493 need it again soon. */
1494 while (displaced
->step_request_queue
)
1496 struct displaced_step_request
*head
;
1498 struct regcache
*regcache
;
1499 struct gdbarch
*gdbarch
;
1500 CORE_ADDR actual_pc
;
1501 struct address_space
*aspace
;
1503 head
= displaced
->step_request_queue
;
1505 displaced
->step_request_queue
= head
->next
;
1508 context_switch (ptid
);
1510 regcache
= get_thread_regcache (ptid
);
1511 actual_pc
= regcache_read_pc (regcache
);
1512 aspace
= get_regcache_aspace (regcache
);
1514 if (breakpoint_here_p (aspace
, actual_pc
))
1516 if (debug_displaced
)
1517 fprintf_unfiltered (gdb_stdlog
,
1518 "displaced: stepping queued %s now\n",
1519 target_pid_to_str (ptid
));
1521 displaced_step_prepare (ptid
);
1523 gdbarch
= get_regcache_arch (regcache
);
1525 if (debug_displaced
)
1527 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1530 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1531 paddress (gdbarch
, actual_pc
));
1532 read_memory (actual_pc
, buf
, sizeof (buf
));
1533 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1536 if (gdbarch_displaced_step_hw_singlestep (gdbarch
,
1537 displaced
->step_closure
))
1538 target_resume (ptid
, 1, GDB_SIGNAL_0
);
1540 target_resume (ptid
, 0, GDB_SIGNAL_0
);
1542 /* Done, we're stepping a thread. */
1548 struct thread_info
*tp
= inferior_thread ();
1550 /* The breakpoint we were sitting under has since been
1552 tp
->control
.trap_expected
= 0;
1554 /* Go back to what we were trying to do. */
1555 step
= currently_stepping (tp
);
1557 if (debug_displaced
)
1558 fprintf_unfiltered (gdb_stdlog
,
1559 "displaced: breakpoint is gone: %s, step(%d)\n",
1560 target_pid_to_str (tp
->ptid
), step
);
1562 target_resume (ptid
, step
, GDB_SIGNAL_0
);
1563 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1565 /* This request was discarded. See if there's any other
1566 thread waiting for its turn. */
1571 /* Update global variables holding ptids to hold NEW_PTID if they were
1572 holding OLD_PTID. */
1574 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1576 struct displaced_step_request
*it
;
1577 struct displaced_step_inferior_state
*displaced
;
1579 if (ptid_equal (inferior_ptid
, old_ptid
))
1580 inferior_ptid
= new_ptid
;
1582 if (ptid_equal (singlestep_ptid
, old_ptid
))
1583 singlestep_ptid
= new_ptid
;
1585 if (ptid_equal (deferred_step_ptid
, old_ptid
))
1586 deferred_step_ptid
= new_ptid
;
1588 for (displaced
= displaced_step_inferior_states
;
1590 displaced
= displaced
->next
)
1592 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
1593 displaced
->step_ptid
= new_ptid
;
1595 for (it
= displaced
->step_request_queue
; it
; it
= it
->next
)
1596 if (ptid_equal (it
->ptid
, old_ptid
))
1597 it
->ptid
= new_ptid
;
1604 /* Things to clean up if we QUIT out of resume (). */
1606 resume_cleanups (void *ignore
)
1611 static const char schedlock_off
[] = "off";
1612 static const char schedlock_on
[] = "on";
1613 static const char schedlock_step
[] = "step";
1614 static const char *const scheduler_enums
[] = {
1620 static const char *scheduler_mode
= schedlock_off
;
1622 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1623 struct cmd_list_element
*c
, const char *value
)
1625 fprintf_filtered (file
,
1626 _("Mode for locking scheduler "
1627 "during execution is \"%s\".\n"),
1632 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1634 if (!target_can_lock_scheduler
)
1636 scheduler_mode
= schedlock_off
;
1637 error (_("Target '%s' cannot support this command."), target_shortname
);
1641 /* True if execution commands resume all threads of all processes by
1642 default; otherwise, resume only threads of the current inferior
1644 int sched_multi
= 0;
1646 /* Try to setup for software single stepping over the specified location.
1647 Return 1 if target_resume() should use hardware single step.
1649 GDBARCH the current gdbarch.
1650 PC the location to step over. */
1653 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1657 if (execution_direction
== EXEC_FORWARD
1658 && gdbarch_software_single_step_p (gdbarch
)
1659 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1662 /* Do not pull these breakpoints until after a `wait' in
1663 `wait_for_inferior'. */
1664 singlestep_breakpoints_inserted_p
= 1;
1665 singlestep_ptid
= inferior_ptid
;
1671 /* Return a ptid representing the set of threads that we will proceed,
1672 in the perspective of the user/frontend. We may actually resume
1673 fewer threads at first, e.g., if a thread is stopped at a
1674 breakpoint that needs stepping-off, but that should not be visible
1675 to the user/frontend, and neither should the frontend/user be
1676 allowed to proceed any of the threads that happen to be stopped for
1677 internal run control handling, if a previous command wanted them
1681 user_visible_resume_ptid (int step
)
1683 /* By default, resume all threads of all processes. */
1684 ptid_t resume_ptid
= RESUME_ALL
;
1686 /* Maybe resume only all threads of the current process. */
1687 if (!sched_multi
&& target_supports_multi_process ())
1689 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
1692 /* Maybe resume a single thread after all. */
1695 /* With non-stop mode on, threads are always handled
1697 resume_ptid
= inferior_ptid
;
1699 else if ((scheduler_mode
== schedlock_on
)
1700 || (scheduler_mode
== schedlock_step
1701 && (step
|| singlestep_breakpoints_inserted_p
)))
1703 /* User-settable 'scheduler' mode requires solo thread resume. */
1704 resume_ptid
= inferior_ptid
;
1710 /* Resume the inferior, but allow a QUIT. This is useful if the user
1711 wants to interrupt some lengthy single-stepping operation
1712 (for child processes, the SIGINT goes to the inferior, and so
1713 we get a SIGINT random_signal, but for remote debugging and perhaps
1714 other targets, that's not true).
1716 STEP nonzero if we should step (zero to continue instead).
1717 SIG is the signal to give the inferior (zero for none). */
1719 resume (int step
, enum gdb_signal sig
)
1721 int should_resume
= 1;
1722 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
1723 struct regcache
*regcache
= get_current_regcache ();
1724 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1725 struct thread_info
*tp
= inferior_thread ();
1726 CORE_ADDR pc
= regcache_read_pc (regcache
);
1727 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1731 if (current_inferior ()->waiting_for_vfork_done
)
1733 /* Don't try to single-step a vfork parent that is waiting for
1734 the child to get out of the shared memory region (by exec'ing
1735 or exiting). This is particularly important on software
1736 single-step archs, as the child process would trip on the
1737 software single step breakpoint inserted for the parent
1738 process. Since the parent will not actually execute any
1739 instruction until the child is out of the shared region (such
1740 are vfork's semantics), it is safe to simply continue it.
1741 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
1742 the parent, and tell it to `keep_going', which automatically
1743 re-sets it stepping. */
1745 fprintf_unfiltered (gdb_stdlog
,
1746 "infrun: resume : clear step\n");
1751 fprintf_unfiltered (gdb_stdlog
,
1752 "infrun: resume (step=%d, signal=%s), "
1753 "trap_expected=%d, current thread [%s] at %s\n",
1754 step
, gdb_signal_to_symbol_string (sig
),
1755 tp
->control
.trap_expected
,
1756 target_pid_to_str (inferior_ptid
),
1757 paddress (gdbarch
, pc
));
1759 /* Normally, by the time we reach `resume', the breakpoints are either
1760 removed or inserted, as appropriate. The exception is if we're sitting
1761 at a permanent breakpoint; we need to step over it, but permanent
1762 breakpoints can't be removed. So we have to test for it here. */
1763 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
1765 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
1766 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
1769 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1770 how to step past a permanent breakpoint on this architecture. Try using\n\
1771 a command like `return' or `jump' to continue execution."));
1774 /* If we have a breakpoint to step over, make sure to do a single
1775 step only. Same if we have software watchpoints. */
1776 if (tp
->control
.trap_expected
|| bpstat_should_step ())
1777 tp
->control
.may_range_step
= 0;
1779 /* If enabled, step over breakpoints by executing a copy of the
1780 instruction at a different address.
1782 We can't use displaced stepping when we have a signal to deliver;
1783 the comments for displaced_step_prepare explain why. The
1784 comments in the handle_inferior event for dealing with 'random
1785 signals' explain what we do instead.
1787 We can't use displaced stepping when we are waiting for vfork_done
1788 event, displaced stepping breaks the vfork child similarly as single
1789 step software breakpoint. */
1790 if (use_displaced_stepping (gdbarch
)
1791 && (tp
->control
.trap_expected
1792 || (step
&& gdbarch_software_single_step_p (gdbarch
)))
1793 && sig
== GDB_SIGNAL_0
1794 && !current_inferior ()->waiting_for_vfork_done
)
1796 struct displaced_step_inferior_state
*displaced
;
1798 if (!displaced_step_prepare (inferior_ptid
))
1800 /* Got placed in displaced stepping queue. Will be resumed
1801 later when all the currently queued displaced stepping
1802 requests finish. The thread is not executing at this point,
1803 and the call to set_executing will be made later. But we
1804 need to call set_running here, since from frontend point of view,
1805 the thread is running. */
1806 set_running (inferior_ptid
, 1);
1807 discard_cleanups (old_cleanups
);
1811 /* Update pc to reflect the new address from which we will execute
1812 instructions due to displaced stepping. */
1813 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
1815 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1816 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
1817 displaced
->step_closure
);
1820 /* Do we need to do it the hard way, w/temp breakpoints? */
1822 step
= maybe_software_singlestep (gdbarch
, pc
);
1824 /* Currently, our software single-step implementation leads to different
1825 results than hardware single-stepping in one situation: when stepping
1826 into delivering a signal which has an associated signal handler,
1827 hardware single-step will stop at the first instruction of the handler,
1828 while software single-step will simply skip execution of the handler.
1830 For now, this difference in behavior is accepted since there is no
1831 easy way to actually implement single-stepping into a signal handler
1832 without kernel support.
1834 However, there is one scenario where this difference leads to follow-on
1835 problems: if we're stepping off a breakpoint by removing all breakpoints
1836 and then single-stepping. In this case, the software single-step
1837 behavior means that even if there is a *breakpoint* in the signal
1838 handler, GDB still would not stop.
1840 Fortunately, we can at least fix this particular issue. We detect
1841 here the case where we are about to deliver a signal while software
1842 single-stepping with breakpoints removed. In this situation, we
1843 revert the decisions to remove all breakpoints and insert single-
1844 step breakpoints, and instead we install a step-resume breakpoint
1845 at the current address, deliver the signal without stepping, and
1846 once we arrive back at the step-resume breakpoint, actually step
1847 over the breakpoint we originally wanted to step over. */
1848 if (singlestep_breakpoints_inserted_p
1849 && tp
->control
.trap_expected
&& sig
!= GDB_SIGNAL_0
)
1851 /* If we have nested signals or a pending signal is delivered
1852 immediately after a handler returns, might might already have
1853 a step-resume breakpoint set on the earlier handler. We cannot
1854 set another step-resume breakpoint; just continue on until the
1855 original breakpoint is hit. */
1856 if (tp
->control
.step_resume_breakpoint
== NULL
)
1858 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
1859 tp
->step_after_step_resume_breakpoint
= 1;
1862 remove_single_step_breakpoints ();
1863 singlestep_breakpoints_inserted_p
= 0;
1865 insert_breakpoints ();
1866 tp
->control
.trap_expected
= 0;
1873 /* If STEP is set, it's a request to use hardware stepping
1874 facilities. But in that case, we should never
1875 use singlestep breakpoint. */
1876 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1878 /* Decide the set of threads to ask the target to resume. Start
1879 by assuming everything will be resumed, than narrow the set
1880 by applying increasingly restricting conditions. */
1881 resume_ptid
= user_visible_resume_ptid (step
);
1883 /* Maybe resume a single thread after all. */
1884 if (singlestep_breakpoints_inserted_p
1885 && stepping_past_singlestep_breakpoint
)
1887 /* The situation here is as follows. In thread T1 we wanted to
1888 single-step. Lacking hardware single-stepping we've
1889 set breakpoint at the PC of the next instruction -- call it
1890 P. After resuming, we've hit that breakpoint in thread T2.
1891 Now we've removed original breakpoint, inserted breakpoint
1892 at P+1, and try to step to advance T2 past breakpoint.
1893 We need to step only T2, as if T1 is allowed to freely run,
1894 it can run past P, and if other threads are allowed to run,
1895 they can hit breakpoint at P+1, and nested hits of single-step
1896 breakpoints is not something we'd want -- that's complicated
1897 to support, and has no value. */
1898 resume_ptid
= inferior_ptid
;
1900 else if ((step
|| singlestep_breakpoints_inserted_p
)
1901 && tp
->control
.trap_expected
)
1903 /* We're allowing a thread to run past a breakpoint it has
1904 hit, by single-stepping the thread with the breakpoint
1905 removed. In which case, we need to single-step only this
1906 thread, and keep others stopped, as they can miss this
1907 breakpoint if allowed to run.
1909 The current code actually removes all breakpoints when
1910 doing this, not just the one being stepped over, so if we
1911 let other threads run, we can actually miss any
1912 breakpoint, not just the one at PC. */
1913 resume_ptid
= inferior_ptid
;
1916 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1918 /* Most targets can step a breakpoint instruction, thus
1919 executing it normally. But if this one cannot, just
1920 continue and we will hit it anyway. */
1921 if (step
&& breakpoint_inserted_here_p (aspace
, pc
))
1926 && use_displaced_stepping (gdbarch
)
1927 && tp
->control
.trap_expected
)
1929 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1930 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
1931 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1934 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1935 paddress (resume_gdbarch
, actual_pc
));
1936 read_memory (actual_pc
, buf
, sizeof (buf
));
1937 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1940 if (tp
->control
.may_range_step
)
1942 /* If we're resuming a thread with the PC out of the step
1943 range, then we're doing some nested/finer run control
1944 operation, like stepping the thread out of the dynamic
1945 linker or the displaced stepping scratch pad. We
1946 shouldn't have allowed a range step then. */
1947 gdb_assert (pc_in_thread_step_range (pc
, tp
));
1950 /* Install inferior's terminal modes. */
1951 target_terminal_inferior ();
1953 /* Avoid confusing the next resume, if the next stop/resume
1954 happens to apply to another thread. */
1955 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1957 /* Advise target which signals may be handled silently. If we have
1958 removed breakpoints because we are stepping over one (which can
1959 happen only if we are not using displaced stepping), we need to
1960 receive all signals to avoid accidentally skipping a breakpoint
1961 during execution of a signal handler. */
1962 if ((step
|| singlestep_breakpoints_inserted_p
)
1963 && tp
->control
.trap_expected
1964 && !use_displaced_stepping (gdbarch
))
1965 target_pass_signals (0, NULL
);
1967 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
1969 target_resume (resume_ptid
, step
, sig
);
1972 discard_cleanups (old_cleanups
);
1977 /* Clear out all variables saying what to do when inferior is continued.
1978 First do this, then set the ones you want, then call `proceed'. */
1981 clear_proceed_status_thread (struct thread_info
*tp
)
1984 fprintf_unfiltered (gdb_stdlog
,
1985 "infrun: clear_proceed_status_thread (%s)\n",
1986 target_pid_to_str (tp
->ptid
));
1988 tp
->control
.trap_expected
= 0;
1989 tp
->control
.step_range_start
= 0;
1990 tp
->control
.step_range_end
= 0;
1991 tp
->control
.may_range_step
= 0;
1992 tp
->control
.step_frame_id
= null_frame_id
;
1993 tp
->control
.step_stack_frame_id
= null_frame_id
;
1994 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1995 tp
->stop_requested
= 0;
1997 tp
->control
.stop_step
= 0;
1999 tp
->control
.proceed_to_finish
= 0;
2001 /* Discard any remaining commands or status from previous stop. */
2002 bpstat_clear (&tp
->control
.stop_bpstat
);
2006 clear_proceed_status_callback (struct thread_info
*tp
, void *data
)
2008 if (is_exited (tp
->ptid
))
2011 clear_proceed_status_thread (tp
);
2016 clear_proceed_status (void)
2020 /* In all-stop mode, delete the per-thread status of all
2021 threads, even if inferior_ptid is null_ptid, there may be
2022 threads on the list. E.g., we may be launching a new
2023 process, while selecting the executable. */
2024 iterate_over_threads (clear_proceed_status_callback
, NULL
);
2027 if (!ptid_equal (inferior_ptid
, null_ptid
))
2029 struct inferior
*inferior
;
2033 /* If in non-stop mode, only delete the per-thread status of
2034 the current thread. */
2035 clear_proceed_status_thread (inferior_thread ());
2038 inferior
= current_inferior ();
2039 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2042 stop_after_trap
= 0;
2044 observer_notify_about_to_proceed ();
2048 regcache_xfree (stop_registers
);
2049 stop_registers
= NULL
;
2053 /* Check the current thread against the thread that reported the most recent
2054 event. If a step-over is required return TRUE and set the current thread
2055 to the old thread. Otherwise return FALSE.
2057 This should be suitable for any targets that support threads. */
2060 prepare_to_proceed (int step
)
2063 struct target_waitstatus wait_status
;
2064 int schedlock_enabled
;
2066 /* With non-stop mode on, threads are always handled individually. */
2067 gdb_assert (! non_stop
);
2069 /* Get the last target status returned by target_wait(). */
2070 get_last_target_status (&wait_ptid
, &wait_status
);
2072 /* Make sure we were stopped at a breakpoint. */
2073 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
2074 || (wait_status
.value
.sig
!= GDB_SIGNAL_TRAP
2075 && wait_status
.value
.sig
!= GDB_SIGNAL_ILL
2076 && wait_status
.value
.sig
!= GDB_SIGNAL_SEGV
2077 && wait_status
.value
.sig
!= GDB_SIGNAL_EMT
))
2082 schedlock_enabled
= (scheduler_mode
== schedlock_on
2083 || (scheduler_mode
== schedlock_step
2086 /* Don't switch over to WAIT_PTID if scheduler locking is on. */
2087 if (schedlock_enabled
)
2090 /* Don't switch over if we're about to resume some other process
2091 other than WAIT_PTID's, and schedule-multiple is off. */
2093 && ptid_get_pid (wait_ptid
) != ptid_get_pid (inferior_ptid
))
2096 /* Switched over from WAIT_PID. */
2097 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
2098 && !ptid_equal (inferior_ptid
, wait_ptid
))
2100 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
2102 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2103 regcache_read_pc (regcache
)))
2105 /* If stepping, remember current thread to switch back to. */
2107 deferred_step_ptid
= inferior_ptid
;
2109 /* Switch back to WAIT_PID thread. */
2110 switch_to_thread (wait_ptid
);
2113 fprintf_unfiltered (gdb_stdlog
,
2114 "infrun: prepare_to_proceed (step=%d), "
2115 "switched to [%s]\n",
2116 step
, target_pid_to_str (inferior_ptid
));
2118 /* We return 1 to indicate that there is a breakpoint here,
2119 so we need to step over it before continuing to avoid
2120 hitting it straight away. */
2128 /* Basic routine for continuing the program in various fashions.
2130 ADDR is the address to resume at, or -1 for resume where stopped.
2131 SIGGNAL is the signal to give it, or 0 for none,
2132 or -1 for act according to how it stopped.
2133 STEP is nonzero if should trap after one instruction.
2134 -1 means return after that and print nothing.
2135 You should probably set various step_... variables
2136 before calling here, if you are stepping.
2138 You should call clear_proceed_status before calling proceed. */
2141 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
, int step
)
2143 struct regcache
*regcache
;
2144 struct gdbarch
*gdbarch
;
2145 struct thread_info
*tp
;
2147 struct address_space
*aspace
;
2148 /* GDB may force the inferior to step due to various reasons. */
2151 /* If we're stopped at a fork/vfork, follow the branch set by the
2152 "set follow-fork-mode" command; otherwise, we'll just proceed
2153 resuming the current thread. */
2154 if (!follow_fork ())
2156 /* The target for some reason decided not to resume. */
2158 if (target_can_async_p ())
2159 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2163 /* We'll update this if & when we switch to a new thread. */
2164 previous_inferior_ptid
= inferior_ptid
;
2166 regcache
= get_current_regcache ();
2167 gdbarch
= get_regcache_arch (regcache
);
2168 aspace
= get_regcache_aspace (regcache
);
2169 pc
= regcache_read_pc (regcache
);
2172 step_start_function
= find_pc_function (pc
);
2174 stop_after_trap
= 1;
2176 if (addr
== (CORE_ADDR
) -1)
2178 if (pc
== stop_pc
&& breakpoint_here_p (aspace
, pc
)
2179 && execution_direction
!= EXEC_REVERSE
)
2180 /* There is a breakpoint at the address we will resume at,
2181 step one instruction before inserting breakpoints so that
2182 we do not stop right away (and report a second hit at this
2185 Note, we don't do this in reverse, because we won't
2186 actually be executing the breakpoint insn anyway.
2187 We'll be (un-)executing the previous instruction. */
2190 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2191 && gdbarch_single_step_through_delay (gdbarch
,
2192 get_current_frame ()))
2193 /* We stepped onto an instruction that needs to be stepped
2194 again before re-inserting the breakpoint, do so. */
2199 regcache_write_pc (regcache
, addr
);
2203 fprintf_unfiltered (gdb_stdlog
,
2204 "infrun: proceed (addr=%s, signal=%s, step=%d)\n",
2205 paddress (gdbarch
, addr
),
2206 gdb_signal_to_symbol_string (siggnal
), step
);
2209 /* In non-stop, each thread is handled individually. The context
2210 must already be set to the right thread here. */
2214 /* In a multi-threaded task we may select another thread and
2215 then continue or step.
2217 But if the old thread was stopped at a breakpoint, it will
2218 immediately cause another breakpoint stop without any
2219 execution (i.e. it will report a breakpoint hit incorrectly).
2220 So we must step over it first.
2222 prepare_to_proceed checks the current thread against the
2223 thread that reported the most recent event. If a step-over
2224 is required it returns TRUE and sets the current thread to
2226 if (prepare_to_proceed (step
))
2230 /* prepare_to_proceed may change the current thread. */
2231 tp
= inferior_thread ();
2235 tp
->control
.trap_expected
= 1;
2236 /* If displaced stepping is enabled, we can step over the
2237 breakpoint without hitting it, so leave all breakpoints
2238 inserted. Otherwise we need to disable all breakpoints, step
2239 one instruction, and then re-add them when that step is
2241 if (!use_displaced_stepping (gdbarch
))
2242 remove_breakpoints ();
2245 /* We can insert breakpoints if we're not trying to step over one,
2246 or if we are stepping over one but we're using displaced stepping
2248 if (! tp
->control
.trap_expected
|| use_displaced_stepping (gdbarch
))
2249 insert_breakpoints ();
2253 /* Pass the last stop signal to the thread we're resuming,
2254 irrespective of whether the current thread is the thread that
2255 got the last event or not. This was historically GDB's
2256 behaviour before keeping a stop_signal per thread. */
2258 struct thread_info
*last_thread
;
2260 struct target_waitstatus last_status
;
2262 get_last_target_status (&last_ptid
, &last_status
);
2263 if (!ptid_equal (inferior_ptid
, last_ptid
)
2264 && !ptid_equal (last_ptid
, null_ptid
)
2265 && !ptid_equal (last_ptid
, minus_one_ptid
))
2267 last_thread
= find_thread_ptid (last_ptid
);
2270 tp
->suspend
.stop_signal
= last_thread
->suspend
.stop_signal
;
2271 last_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2276 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2277 tp
->suspend
.stop_signal
= siggnal
;
2278 /* If this signal should not be seen by program,
2279 give it zero. Used for debugging signals. */
2280 else if (!signal_program
[tp
->suspend
.stop_signal
])
2281 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2283 annotate_starting ();
2285 /* Make sure that output from GDB appears before output from the
2287 gdb_flush (gdb_stdout
);
2289 /* Refresh prev_pc value just prior to resuming. This used to be
2290 done in stop_stepping, however, setting prev_pc there did not handle
2291 scenarios such as inferior function calls or returning from
2292 a function via the return command. In those cases, the prev_pc
2293 value was not set properly for subsequent commands. The prev_pc value
2294 is used to initialize the starting line number in the ecs. With an
2295 invalid value, the gdb next command ends up stopping at the position
2296 represented by the next line table entry past our start position.
2297 On platforms that generate one line table entry per line, this
2298 is not a problem. However, on the ia64, the compiler generates
2299 extraneous line table entries that do not increase the line number.
2300 When we issue the gdb next command on the ia64 after an inferior call
2301 or a return command, we often end up a few instructions forward, still
2302 within the original line we started.
2304 An attempt was made to refresh the prev_pc at the same time the
2305 execution_control_state is initialized (for instance, just before
2306 waiting for an inferior event). But this approach did not work
2307 because of platforms that use ptrace, where the pc register cannot
2308 be read unless the inferior is stopped. At that point, we are not
2309 guaranteed the inferior is stopped and so the regcache_read_pc() call
2310 can fail. Setting the prev_pc value here ensures the value is updated
2311 correctly when the inferior is stopped. */
2312 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2314 /* Fill in with reasonable starting values. */
2315 init_thread_stepping_state (tp
);
2317 /* Reset to normal state. */
2318 init_infwait_state ();
2320 /* Resume inferior. */
2321 resume (force_step
|| step
|| bpstat_should_step (),
2322 tp
->suspend
.stop_signal
);
2324 /* Wait for it to stop (if not standalone)
2325 and in any case decode why it stopped, and act accordingly. */
2326 /* Do this only if we are not using the event loop, or if the target
2327 does not support asynchronous execution. */
2328 if (!target_can_async_p ())
2330 wait_for_inferior ();
2336 /* Start remote-debugging of a machine over a serial link. */
2339 start_remote (int from_tty
)
2341 struct inferior
*inferior
;
2343 inferior
= current_inferior ();
2344 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2346 /* Always go on waiting for the target, regardless of the mode. */
2347 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2348 indicate to wait_for_inferior that a target should timeout if
2349 nothing is returned (instead of just blocking). Because of this,
2350 targets expecting an immediate response need to, internally, set
2351 things up so that the target_wait() is forced to eventually
2353 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2354 differentiate to its caller what the state of the target is after
2355 the initial open has been performed. Here we're assuming that
2356 the target has stopped. It should be possible to eventually have
2357 target_open() return to the caller an indication that the target
2358 is currently running and GDB state should be set to the same as
2359 for an async run. */
2360 wait_for_inferior ();
2362 /* Now that the inferior has stopped, do any bookkeeping like
2363 loading shared libraries. We want to do this before normal_stop,
2364 so that the displayed frame is up to date. */
2365 post_create_inferior (¤t_target
, from_tty
);
2370 /* Initialize static vars when a new inferior begins. */
2373 init_wait_for_inferior (void)
2375 /* These are meaningless until the first time through wait_for_inferior. */
2377 breakpoint_init_inferior (inf_starting
);
2379 clear_proceed_status ();
2381 stepping_past_singlestep_breakpoint
= 0;
2382 deferred_step_ptid
= null_ptid
;
2384 target_last_wait_ptid
= minus_one_ptid
;
2386 previous_inferior_ptid
= inferior_ptid
;
2387 init_infwait_state ();
2389 /* Discard any skipped inlined frames. */
2390 clear_inline_frame_state (minus_one_ptid
);
2394 /* This enum encodes possible reasons for doing a target_wait, so that
2395 wfi can call target_wait in one place. (Ultimately the call will be
2396 moved out of the infinite loop entirely.) */
2400 infwait_normal_state
,
2401 infwait_thread_hop_state
,
2402 infwait_step_watch_state
,
2403 infwait_nonstep_watch_state
2406 /* The PTID we'll do a target_wait on.*/
2409 /* Current inferior wait state. */
2410 static enum infwait_states infwait_state
;
2412 /* Data to be passed around while handling an event. This data is
2413 discarded between events. */
2414 struct execution_control_state
2417 /* The thread that got the event, if this was a thread event; NULL
2419 struct thread_info
*event_thread
;
2421 struct target_waitstatus ws
;
2422 int stop_func_filled_in
;
2423 CORE_ADDR stop_func_start
;
2424 CORE_ADDR stop_func_end
;
2425 const char *stop_func_name
;
2428 /* We were in infwait_step_watch_state or
2429 infwait_nonstep_watch_state state, and the thread reported an
2431 int stepped_after_stopped_by_watchpoint
;
2434 static void handle_inferior_event (struct execution_control_state
*ecs
);
2436 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2437 struct execution_control_state
*ecs
);
2438 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2439 struct execution_control_state
*ecs
);
2440 static void handle_signal_stop (struct execution_control_state
*ecs
);
2441 static void check_exception_resume (struct execution_control_state
*,
2442 struct frame_info
*);
2444 static void stop_stepping (struct execution_control_state
*ecs
);
2445 static void prepare_to_wait (struct execution_control_state
*ecs
);
2446 static void keep_going (struct execution_control_state
*ecs
);
2447 static void process_event_stop_test (struct execution_control_state
*ecs
);
2448 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
2450 /* Callback for iterate over threads. If the thread is stopped, but
2451 the user/frontend doesn't know about that yet, go through
2452 normal_stop, as if the thread had just stopped now. ARG points at
2453 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2454 ptid_is_pid(PTID) is true, applies to all threads of the process
2455 pointed at by PTID. Otherwise, apply only to the thread pointed by
2459 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2461 ptid_t ptid
= * (ptid_t
*) arg
;
2463 if ((ptid_equal (info
->ptid
, ptid
)
2464 || ptid_equal (minus_one_ptid
, ptid
)
2465 || (ptid_is_pid (ptid
)
2466 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2467 && is_running (info
->ptid
)
2468 && !is_executing (info
->ptid
))
2470 struct cleanup
*old_chain
;
2471 struct execution_control_state ecss
;
2472 struct execution_control_state
*ecs
= &ecss
;
2474 memset (ecs
, 0, sizeof (*ecs
));
2476 old_chain
= make_cleanup_restore_current_thread ();
2478 /* Go through handle_inferior_event/normal_stop, so we always
2479 have consistent output as if the stop event had been
2481 ecs
->ptid
= info
->ptid
;
2482 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2483 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2484 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2486 handle_inferior_event (ecs
);
2488 if (!ecs
->wait_some_more
)
2490 struct thread_info
*tp
;
2494 /* Finish off the continuations. */
2495 tp
= inferior_thread ();
2496 do_all_intermediate_continuations_thread (tp
, 1);
2497 do_all_continuations_thread (tp
, 1);
2500 do_cleanups (old_chain
);
2506 /* This function is attached as a "thread_stop_requested" observer.
2507 Cleanup local state that assumed the PTID was to be resumed, and
2508 report the stop to the frontend. */
2511 infrun_thread_stop_requested (ptid_t ptid
)
2513 struct displaced_step_inferior_state
*displaced
;
2515 /* PTID was requested to stop. Remove it from the displaced
2516 stepping queue, so we don't try to resume it automatically. */
2518 for (displaced
= displaced_step_inferior_states
;
2520 displaced
= displaced
->next
)
2522 struct displaced_step_request
*it
, **prev_next_p
;
2524 it
= displaced
->step_request_queue
;
2525 prev_next_p
= &displaced
->step_request_queue
;
2528 if (ptid_match (it
->ptid
, ptid
))
2530 *prev_next_p
= it
->next
;
2536 prev_next_p
= &it
->next
;
2543 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2547 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2549 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2550 nullify_last_target_wait_ptid ();
2553 /* Callback for iterate_over_threads. */
2556 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
2558 if (is_exited (info
->ptid
))
2561 delete_step_resume_breakpoint (info
);
2562 delete_exception_resume_breakpoint (info
);
2566 /* In all-stop, delete the step resume breakpoint of any thread that
2567 had one. In non-stop, delete the step resume breakpoint of the
2568 thread that just stopped. */
2571 delete_step_thread_step_resume_breakpoint (void)
2573 if (!target_has_execution
2574 || ptid_equal (inferior_ptid
, null_ptid
))
2575 /* If the inferior has exited, we have already deleted the step
2576 resume breakpoints out of GDB's lists. */
2581 /* If in non-stop mode, only delete the step-resume or
2582 longjmp-resume breakpoint of the thread that just stopped
2584 struct thread_info
*tp
= inferior_thread ();
2586 delete_step_resume_breakpoint (tp
);
2587 delete_exception_resume_breakpoint (tp
);
2590 /* In all-stop mode, delete all step-resume and longjmp-resume
2591 breakpoints of any thread that had them. */
2592 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
2595 /* A cleanup wrapper. */
2598 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
2600 delete_step_thread_step_resume_breakpoint ();
2603 /* Pretty print the results of target_wait, for debugging purposes. */
2606 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
2607 const struct target_waitstatus
*ws
)
2609 char *status_string
= target_waitstatus_to_string (ws
);
2610 struct ui_file
*tmp_stream
= mem_fileopen ();
2613 /* The text is split over several lines because it was getting too long.
2614 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2615 output as a unit; we want only one timestamp printed if debug_timestamp
2618 fprintf_unfiltered (tmp_stream
,
2619 "infrun: target_wait (%d", ptid_get_pid (waiton_ptid
));
2620 if (ptid_get_pid (waiton_ptid
) != -1)
2621 fprintf_unfiltered (tmp_stream
,
2622 " [%s]", target_pid_to_str (waiton_ptid
));
2623 fprintf_unfiltered (tmp_stream
, ", status) =\n");
2624 fprintf_unfiltered (tmp_stream
,
2625 "infrun: %d [%s],\n",
2626 ptid_get_pid (result_ptid
),
2627 target_pid_to_str (result_ptid
));
2628 fprintf_unfiltered (tmp_stream
,
2632 text
= ui_file_xstrdup (tmp_stream
, NULL
);
2634 /* This uses %s in part to handle %'s in the text, but also to avoid
2635 a gcc error: the format attribute requires a string literal. */
2636 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
2638 xfree (status_string
);
2640 ui_file_delete (tmp_stream
);
2643 /* Prepare and stabilize the inferior for detaching it. E.g.,
2644 detaching while a thread is displaced stepping is a recipe for
2645 crashing it, as nothing would readjust the PC out of the scratch
2649 prepare_for_detach (void)
2651 struct inferior
*inf
= current_inferior ();
2652 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
2653 struct cleanup
*old_chain_1
;
2654 struct displaced_step_inferior_state
*displaced
;
2656 displaced
= get_displaced_stepping_state (inf
->pid
);
2658 /* Is any thread of this process displaced stepping? If not,
2659 there's nothing else to do. */
2660 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
2664 fprintf_unfiltered (gdb_stdlog
,
2665 "displaced-stepping in-process while detaching");
2667 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
2670 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
2672 struct cleanup
*old_chain_2
;
2673 struct execution_control_state ecss
;
2674 struct execution_control_state
*ecs
;
2677 memset (ecs
, 0, sizeof (*ecs
));
2679 overlay_cache_invalid
= 1;
2681 if (deprecated_target_wait_hook
)
2682 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
2684 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
2687 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
2689 /* If an error happens while handling the event, propagate GDB's
2690 knowledge of the executing state to the frontend/user running
2692 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
2695 /* Now figure out what to do with the result of the result. */
2696 handle_inferior_event (ecs
);
2698 /* No error, don't finish the state yet. */
2699 discard_cleanups (old_chain_2
);
2701 /* Breakpoints and watchpoints are not installed on the target
2702 at this point, and signals are passed directly to the
2703 inferior, so this must mean the process is gone. */
2704 if (!ecs
->wait_some_more
)
2706 discard_cleanups (old_chain_1
);
2707 error (_("Program exited while detaching"));
2711 discard_cleanups (old_chain_1
);
2714 /* Wait for control to return from inferior to debugger.
2716 If inferior gets a signal, we may decide to start it up again
2717 instead of returning. That is why there is a loop in this function.
2718 When this function actually returns it means the inferior
2719 should be left stopped and GDB should read more commands. */
2722 wait_for_inferior (void)
2724 struct cleanup
*old_cleanups
;
2728 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
2731 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
2735 struct execution_control_state ecss
;
2736 struct execution_control_state
*ecs
= &ecss
;
2737 struct cleanup
*old_chain
;
2739 memset (ecs
, 0, sizeof (*ecs
));
2741 overlay_cache_invalid
= 1;
2743 if (deprecated_target_wait_hook
)
2744 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
2746 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
2749 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2751 /* If an error happens while handling the event, propagate GDB's
2752 knowledge of the executing state to the frontend/user running
2754 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2756 /* Now figure out what to do with the result of the result. */
2757 handle_inferior_event (ecs
);
2759 /* No error, don't finish the state yet. */
2760 discard_cleanups (old_chain
);
2762 if (!ecs
->wait_some_more
)
2766 do_cleanups (old_cleanups
);
2769 /* Asynchronous version of wait_for_inferior. It is called by the
2770 event loop whenever a change of state is detected on the file
2771 descriptor corresponding to the target. It can be called more than
2772 once to complete a single execution command. In such cases we need
2773 to keep the state in a global variable ECSS. If it is the last time
2774 that this function is called for a single execution command, then
2775 report to the user that the inferior has stopped, and do the
2776 necessary cleanups. */
2779 fetch_inferior_event (void *client_data
)
2781 struct execution_control_state ecss
;
2782 struct execution_control_state
*ecs
= &ecss
;
2783 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
2784 struct cleanup
*ts_old_chain
;
2785 int was_sync
= sync_execution
;
2788 memset (ecs
, 0, sizeof (*ecs
));
2790 /* We're handling a live event, so make sure we're doing live
2791 debugging. If we're looking at traceframes while the target is
2792 running, we're going to need to get back to that mode after
2793 handling the event. */
2796 make_cleanup_restore_current_traceframe ();
2797 set_current_traceframe (-1);
2801 /* In non-stop mode, the user/frontend should not notice a thread
2802 switch due to internal events. Make sure we reverse to the
2803 user selected thread and frame after handling the event and
2804 running any breakpoint commands. */
2805 make_cleanup_restore_current_thread ();
2807 overlay_cache_invalid
= 1;
2809 make_cleanup_restore_integer (&execution_direction
);
2810 execution_direction
= target_execution_direction ();
2812 if (deprecated_target_wait_hook
)
2814 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2816 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2819 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2821 /* If an error happens while handling the event, propagate GDB's
2822 knowledge of the executing state to the frontend/user running
2825 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2827 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
2829 /* Get executed before make_cleanup_restore_current_thread above to apply
2830 still for the thread which has thrown the exception. */
2831 make_bpstat_clear_actions_cleanup ();
2833 /* Now figure out what to do with the result of the result. */
2834 handle_inferior_event (ecs
);
2836 if (!ecs
->wait_some_more
)
2838 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2840 delete_step_thread_step_resume_breakpoint ();
2842 /* We may not find an inferior if this was a process exit. */
2843 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
2846 if (target_has_execution
2847 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
2848 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2849 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2850 && ecs
->event_thread
->step_multi
2851 && ecs
->event_thread
->control
.stop_step
)
2852 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
2855 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2860 /* No error, don't finish the thread states yet. */
2861 discard_cleanups (ts_old_chain
);
2863 /* Revert thread and frame. */
2864 do_cleanups (old_chain
);
2866 /* If the inferior was in sync execution mode, and now isn't,
2867 restore the prompt (a synchronous execution command has finished,
2868 and we're ready for input). */
2869 if (interpreter_async
&& was_sync
&& !sync_execution
)
2870 display_gdb_prompt (0);
2874 && exec_done_display_p
2875 && (ptid_equal (inferior_ptid
, null_ptid
)
2876 || !is_running (inferior_ptid
)))
2877 printf_unfiltered (_("completed.\n"));
2880 /* Record the frame and location we're currently stepping through. */
2882 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
2884 struct thread_info
*tp
= inferior_thread ();
2886 tp
->control
.step_frame_id
= get_frame_id (frame
);
2887 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
2889 tp
->current_symtab
= sal
.symtab
;
2890 tp
->current_line
= sal
.line
;
2893 /* Clear context switchable stepping state. */
2896 init_thread_stepping_state (struct thread_info
*tss
)
2898 tss
->stepping_over_breakpoint
= 0;
2899 tss
->step_after_step_resume_breakpoint
= 0;
2902 /* Return the cached copy of the last pid/waitstatus returned by
2903 target_wait()/deprecated_target_wait_hook(). The data is actually
2904 cached by handle_inferior_event(), which gets called immediately
2905 after target_wait()/deprecated_target_wait_hook(). */
2908 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
2910 *ptidp
= target_last_wait_ptid
;
2911 *status
= target_last_waitstatus
;
2915 nullify_last_target_wait_ptid (void)
2917 target_last_wait_ptid
= minus_one_ptid
;
2920 /* Switch thread contexts. */
2923 context_switch (ptid_t ptid
)
2925 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
2927 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
2928 target_pid_to_str (inferior_ptid
));
2929 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
2930 target_pid_to_str (ptid
));
2933 switch_to_thread (ptid
);
2937 adjust_pc_after_break (struct execution_control_state
*ecs
)
2939 struct regcache
*regcache
;
2940 struct gdbarch
*gdbarch
;
2941 struct address_space
*aspace
;
2942 CORE_ADDR breakpoint_pc
;
2944 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2945 we aren't, just return.
2947 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2948 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2949 implemented by software breakpoints should be handled through the normal
2952 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2953 different signals (SIGILL or SIGEMT for instance), but it is less
2954 clear where the PC is pointing afterwards. It may not match
2955 gdbarch_decr_pc_after_break. I don't know any specific target that
2956 generates these signals at breakpoints (the code has been in GDB since at
2957 least 1992) so I can not guess how to handle them here.
2959 In earlier versions of GDB, a target with
2960 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2961 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2962 target with both of these set in GDB history, and it seems unlikely to be
2963 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2965 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
2968 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
2971 /* In reverse execution, when a breakpoint is hit, the instruction
2972 under it has already been de-executed. The reported PC always
2973 points at the breakpoint address, so adjusting it further would
2974 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2977 B1 0x08000000 : INSN1
2978 B2 0x08000001 : INSN2
2980 PC -> 0x08000003 : INSN4
2982 Say you're stopped at 0x08000003 as above. Reverse continuing
2983 from that point should hit B2 as below. Reading the PC when the
2984 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2985 been de-executed already.
2987 B1 0x08000000 : INSN1
2988 B2 PC -> 0x08000001 : INSN2
2992 We can't apply the same logic as for forward execution, because
2993 we would wrongly adjust the PC to 0x08000000, since there's a
2994 breakpoint at PC - 1. We'd then report a hit on B1, although
2995 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2997 if (execution_direction
== EXEC_REVERSE
)
3000 /* If this target does not decrement the PC after breakpoints, then
3001 we have nothing to do. */
3002 regcache
= get_thread_regcache (ecs
->ptid
);
3003 gdbarch
= get_regcache_arch (regcache
);
3004 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
3007 aspace
= get_regcache_aspace (regcache
);
3009 /* Find the location where (if we've hit a breakpoint) the
3010 breakpoint would be. */
3011 breakpoint_pc
= regcache_read_pc (regcache
)
3012 - gdbarch_decr_pc_after_break (gdbarch
);
3014 /* Check whether there actually is a software breakpoint inserted at
3017 If in non-stop mode, a race condition is possible where we've
3018 removed a breakpoint, but stop events for that breakpoint were
3019 already queued and arrive later. To suppress those spurious
3020 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3021 and retire them after a number of stop events are reported. */
3022 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3023 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3025 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
3028 record_full_gdb_operation_disable_set ();
3030 /* When using hardware single-step, a SIGTRAP is reported for both
3031 a completed single-step and a software breakpoint. Need to
3032 differentiate between the two, as the latter needs adjusting
3033 but the former does not.
3035 The SIGTRAP can be due to a completed hardware single-step only if
3036 - we didn't insert software single-step breakpoints
3037 - the thread to be examined is still the current thread
3038 - this thread is currently being stepped
3040 If any of these events did not occur, we must have stopped due
3041 to hitting a software breakpoint, and have to back up to the
3044 As a special case, we could have hardware single-stepped a
3045 software breakpoint. In this case (prev_pc == breakpoint_pc),
3046 we also need to back up to the breakpoint address. */
3048 if (singlestep_breakpoints_inserted_p
3049 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
3050 || !currently_stepping (ecs
->event_thread
)
3051 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
3052 regcache_write_pc (regcache
, breakpoint_pc
);
3054 do_cleanups (old_cleanups
);
3059 init_infwait_state (void)
3061 waiton_ptid
= pid_to_ptid (-1);
3062 infwait_state
= infwait_normal_state
;
3066 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3068 for (frame
= get_prev_frame (frame
);
3070 frame
= get_prev_frame (frame
))
3072 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3074 if (get_frame_type (frame
) != INLINE_FRAME
)
3081 /* Auxiliary function that handles syscall entry/return events.
3082 It returns 1 if the inferior should keep going (and GDB
3083 should ignore the event), or 0 if the event deserves to be
3087 handle_syscall_event (struct execution_control_state
*ecs
)
3089 struct regcache
*regcache
;
3092 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3093 context_switch (ecs
->ptid
);
3095 regcache
= get_thread_regcache (ecs
->ptid
);
3096 syscall_number
= ecs
->ws
.value
.syscall_number
;
3097 stop_pc
= regcache_read_pc (regcache
);
3099 if (catch_syscall_enabled () > 0
3100 && catching_syscall_number (syscall_number
) > 0)
3103 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3106 ecs
->event_thread
->control
.stop_bpstat
3107 = bpstat_stop_status (get_regcache_aspace (regcache
),
3108 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3110 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3112 /* Catchpoint hit. */
3117 /* If no catchpoint triggered for this, then keep going. */
3122 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3125 fill_in_stop_func (struct gdbarch
*gdbarch
,
3126 struct execution_control_state
*ecs
)
3128 if (!ecs
->stop_func_filled_in
)
3130 /* Don't care about return value; stop_func_start and stop_func_name
3131 will both be 0 if it doesn't work. */
3132 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3133 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3134 ecs
->stop_func_start
3135 += gdbarch_deprecated_function_start_offset (gdbarch
);
3137 ecs
->stop_func_filled_in
= 1;
3142 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
3144 static enum stop_kind
3145 get_inferior_stop_soon (ptid_t ptid
)
3147 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ptid
));
3149 gdb_assert (inf
!= NULL
);
3150 return inf
->control
.stop_soon
;
3153 /* Given an execution control state that has been freshly filled in by
3154 an event from the inferior, figure out what it means and take
3157 The alternatives are:
3159 1) stop_stepping and return; to really stop and return to the
3162 2) keep_going and return; to wait for the next event (set
3163 ecs->event_thread->stepping_over_breakpoint to 1 to single step
3167 handle_inferior_event (struct execution_control_state
*ecs
)
3169 enum stop_kind stop_soon
;
3171 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3173 /* We had an event in the inferior, but we are not interested in
3174 handling it at this level. The lower layers have already
3175 done what needs to be done, if anything.
3177 One of the possible circumstances for this is when the
3178 inferior produces output for the console. The inferior has
3179 not stopped, and we are ignoring the event. Another possible
3180 circumstance is any event which the lower level knows will be
3181 reported multiple times without an intervening resume. */
3183 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3184 prepare_to_wait (ecs
);
3188 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3189 && target_can_async_p () && !sync_execution
)
3191 /* There were no unwaited-for children left in the target, but,
3192 we're not synchronously waiting for events either. Just
3193 ignore. Otherwise, if we were running a synchronous
3194 execution command, we need to cancel it and give the user
3195 back the terminal. */
3197 fprintf_unfiltered (gdb_stdlog
,
3198 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3199 prepare_to_wait (ecs
);
3203 /* Cache the last pid/waitstatus. */
3204 target_last_wait_ptid
= ecs
->ptid
;
3205 target_last_waitstatus
= ecs
->ws
;
3207 /* Always clear state belonging to the previous time we stopped. */
3208 stop_stack_dummy
= STOP_NONE
;
3210 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3212 /* No unwaited-for children left. IOW, all resumed children
3215 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3217 stop_print_frame
= 0;
3218 stop_stepping (ecs
);
3222 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3223 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
3225 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3226 /* If it's a new thread, add it to the thread database. */
3227 if (ecs
->event_thread
== NULL
)
3228 ecs
->event_thread
= add_thread (ecs
->ptid
);
3230 /* Disable range stepping. If the next step request could use a
3231 range, this will be end up re-enabled then. */
3232 ecs
->event_thread
->control
.may_range_step
= 0;
3235 /* Dependent on valid ECS->EVENT_THREAD. */
3236 adjust_pc_after_break (ecs
);
3238 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3239 reinit_frame_cache ();
3241 breakpoint_retire_moribund ();
3243 /* First, distinguish signals caused by the debugger from signals
3244 that have to do with the program's own actions. Note that
3245 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3246 on the operating system version. Here we detect when a SIGILL or
3247 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3248 something similar for SIGSEGV, since a SIGSEGV will be generated
3249 when we're trying to execute a breakpoint instruction on a
3250 non-executable stack. This happens for call dummy breakpoints
3251 for architectures like SPARC that place call dummies on the
3253 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3254 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3255 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3256 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3258 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3260 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3261 regcache_read_pc (regcache
)))
3264 fprintf_unfiltered (gdb_stdlog
,
3265 "infrun: Treating signal as SIGTRAP\n");
3266 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3270 /* Mark the non-executing threads accordingly. In all-stop, all
3271 threads of all processes are stopped when we get any event
3272 reported. In non-stop mode, only the event thread stops. If
3273 we're handling a process exit in non-stop mode, there's nothing
3274 to do, as threads of the dead process are gone, and threads of
3275 any other process were left running. */
3277 set_executing (minus_one_ptid
, 0);
3278 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3279 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3280 set_executing (ecs
->ptid
, 0);
3282 switch (infwait_state
)
3284 case infwait_thread_hop_state
:
3286 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
3289 case infwait_normal_state
:
3291 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
3294 case infwait_step_watch_state
:
3296 fprintf_unfiltered (gdb_stdlog
,
3297 "infrun: infwait_step_watch_state\n");
3299 ecs
->stepped_after_stopped_by_watchpoint
= 1;
3302 case infwait_nonstep_watch_state
:
3304 fprintf_unfiltered (gdb_stdlog
,
3305 "infrun: infwait_nonstep_watch_state\n");
3306 insert_breakpoints ();
3308 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3309 handle things like signals arriving and other things happening
3310 in combination correctly? */
3311 ecs
->stepped_after_stopped_by_watchpoint
= 1;
3315 internal_error (__FILE__
, __LINE__
, _("bad switch"));
3318 infwait_state
= infwait_normal_state
;
3319 waiton_ptid
= pid_to_ptid (-1);
3321 switch (ecs
->ws
.kind
)
3323 case TARGET_WAITKIND_LOADED
:
3325 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3326 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3327 context_switch (ecs
->ptid
);
3328 /* Ignore gracefully during startup of the inferior, as it might
3329 be the shell which has just loaded some objects, otherwise
3330 add the symbols for the newly loaded objects. Also ignore at
3331 the beginning of an attach or remote session; we will query
3332 the full list of libraries once the connection is
3335 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
3336 if (stop_soon
== NO_STOP_QUIETLY
)
3338 struct regcache
*regcache
;
3340 regcache
= get_thread_regcache (ecs
->ptid
);
3342 handle_solib_event ();
3344 ecs
->event_thread
->control
.stop_bpstat
3345 = bpstat_stop_status (get_regcache_aspace (regcache
),
3346 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3348 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3350 /* A catchpoint triggered. */
3351 process_event_stop_test (ecs
);
3355 /* If requested, stop when the dynamic linker notifies
3356 gdb of events. This allows the user to get control
3357 and place breakpoints in initializer routines for
3358 dynamically loaded objects (among other things). */
3359 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3360 if (stop_on_solib_events
)
3362 /* Make sure we print "Stopped due to solib-event" in
3364 stop_print_frame
= 1;
3366 stop_stepping (ecs
);
3371 /* If we are skipping through a shell, or through shared library
3372 loading that we aren't interested in, resume the program. If
3373 we're running the program normally, also resume. */
3374 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3376 /* Loading of shared libraries might have changed breakpoint
3377 addresses. Make sure new breakpoints are inserted. */
3378 if (stop_soon
== NO_STOP_QUIETLY
3379 && !breakpoints_always_inserted_mode ())
3380 insert_breakpoints ();
3381 resume (0, GDB_SIGNAL_0
);
3382 prepare_to_wait (ecs
);
3386 /* But stop if we're attaching or setting up a remote
3388 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3389 || stop_soon
== STOP_QUIETLY_REMOTE
)
3392 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3393 stop_stepping (ecs
);
3397 internal_error (__FILE__
, __LINE__
,
3398 _("unhandled stop_soon: %d"), (int) stop_soon
);
3400 case TARGET_WAITKIND_SPURIOUS
:
3402 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3403 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3404 context_switch (ecs
->ptid
);
3405 resume (0, GDB_SIGNAL_0
);
3406 prepare_to_wait (ecs
);
3409 case TARGET_WAITKIND_EXITED
:
3410 case TARGET_WAITKIND_SIGNALLED
:
3413 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3414 fprintf_unfiltered (gdb_stdlog
,
3415 "infrun: TARGET_WAITKIND_EXITED\n");
3417 fprintf_unfiltered (gdb_stdlog
,
3418 "infrun: TARGET_WAITKIND_SIGNALLED\n");
3421 inferior_ptid
= ecs
->ptid
;
3422 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3423 set_current_program_space (current_inferior ()->pspace
);
3424 handle_vfork_child_exec_or_exit (0);
3425 target_terminal_ours (); /* Must do this before mourn anyway. */
3427 /* Clearing any previous state of convenience variables. */
3428 clear_exit_convenience_vars ();
3430 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3432 /* Record the exit code in the convenience variable $_exitcode, so
3433 that the user can inspect this again later. */
3434 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3435 (LONGEST
) ecs
->ws
.value
.integer
);
3437 /* Also record this in the inferior itself. */
3438 current_inferior ()->has_exit_code
= 1;
3439 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3441 print_exited_reason (ecs
->ws
.value
.integer
);
3445 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3446 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3448 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
3450 /* Set the value of the internal variable $_exitsignal,
3451 which holds the signal uncaught by the inferior. */
3452 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
3453 gdbarch_gdb_signal_to_target (gdbarch
,
3454 ecs
->ws
.value
.sig
));
3458 /* We don't have access to the target's method used for
3459 converting between signal numbers (GDB's internal
3460 representation <-> target's representation).
3461 Therefore, we cannot do a good job at displaying this
3462 information to the user. It's better to just warn
3463 her about it (if infrun debugging is enabled), and
3466 fprintf_filtered (gdb_stdlog
, _("\
3467 Cannot fill $_exitsignal with the correct signal number.\n"));
3470 print_signal_exited_reason (ecs
->ws
.value
.sig
);
3473 gdb_flush (gdb_stdout
);
3474 target_mourn_inferior ();
3475 singlestep_breakpoints_inserted_p
= 0;
3476 cancel_single_step_breakpoints ();
3477 stop_print_frame
= 0;
3478 stop_stepping (ecs
);
3481 /* The following are the only cases in which we keep going;
3482 the above cases end in a continue or goto. */
3483 case TARGET_WAITKIND_FORKED
:
3484 case TARGET_WAITKIND_VFORKED
:
3487 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3488 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3490 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
3493 /* Check whether the inferior is displaced stepping. */
3495 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3496 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3497 struct displaced_step_inferior_state
*displaced
3498 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3500 /* If checking displaced stepping is supported, and thread
3501 ecs->ptid is displaced stepping. */
3502 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3504 struct inferior
*parent_inf
3505 = find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3506 struct regcache
*child_regcache
;
3507 CORE_ADDR parent_pc
;
3509 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3510 indicating that the displaced stepping of syscall instruction
3511 has been done. Perform cleanup for parent process here. Note
3512 that this operation also cleans up the child process for vfork,
3513 because their pages are shared. */
3514 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3516 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3518 /* Restore scratch pad for child process. */
3519 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3522 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3523 the child's PC is also within the scratchpad. Set the child's PC
3524 to the parent's PC value, which has already been fixed up.
3525 FIXME: we use the parent's aspace here, although we're touching
3526 the child, because the child hasn't been added to the inferior
3527 list yet at this point. */
3530 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3532 parent_inf
->aspace
);
3533 /* Read PC value of parent process. */
3534 parent_pc
= regcache_read_pc (regcache
);
3536 if (debug_displaced
)
3537 fprintf_unfiltered (gdb_stdlog
,
3538 "displaced: write child pc from %s to %s\n",
3540 regcache_read_pc (child_regcache
)),
3541 paddress (gdbarch
, parent_pc
));
3543 regcache_write_pc (child_regcache
, parent_pc
);
3547 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3548 context_switch (ecs
->ptid
);
3550 /* Immediately detach breakpoints from the child before there's
3551 any chance of letting the user delete breakpoints from the
3552 breakpoint lists. If we don't do this early, it's easy to
3553 leave left over traps in the child, vis: "break foo; catch
3554 fork; c; <fork>; del; c; <child calls foo>". We only follow
3555 the fork on the last `continue', and by that time the
3556 breakpoint at "foo" is long gone from the breakpoint table.
3557 If we vforked, then we don't need to unpatch here, since both
3558 parent and child are sharing the same memory pages; we'll
3559 need to unpatch at follow/detach time instead to be certain
3560 that new breakpoints added between catchpoint hit time and
3561 vfork follow are detached. */
3562 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3564 /* This won't actually modify the breakpoint list, but will
3565 physically remove the breakpoints from the child. */
3566 detach_breakpoints (ecs
->ws
.value
.related_pid
);
3569 if (singlestep_breakpoints_inserted_p
)
3571 /* Pull the single step breakpoints out of the target. */
3572 remove_single_step_breakpoints ();
3573 singlestep_breakpoints_inserted_p
= 0;
3576 /* In case the event is caught by a catchpoint, remember that
3577 the event is to be followed at the next resume of the thread,
3578 and not immediately. */
3579 ecs
->event_thread
->pending_follow
= ecs
->ws
;
3581 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3583 ecs
->event_thread
->control
.stop_bpstat
3584 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3585 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3587 /* If no catchpoint triggered for this, then keep going. Note
3588 that we're interested in knowing the bpstat actually causes a
3589 stop, not just if it may explain the signal. Software
3590 watchpoints, for example, always appear in the bpstat. */
3591 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3597 = (follow_fork_mode_string
== follow_fork_mode_child
);
3599 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3601 should_resume
= follow_fork ();
3604 child
= ecs
->ws
.value
.related_pid
;
3606 /* In non-stop mode, also resume the other branch. */
3607 if (non_stop
&& !detach_fork
)
3610 switch_to_thread (parent
);
3612 switch_to_thread (child
);
3614 ecs
->event_thread
= inferior_thread ();
3615 ecs
->ptid
= inferior_ptid
;
3620 switch_to_thread (child
);
3622 switch_to_thread (parent
);
3624 ecs
->event_thread
= inferior_thread ();
3625 ecs
->ptid
= inferior_ptid
;
3630 stop_stepping (ecs
);
3633 process_event_stop_test (ecs
);
3636 case TARGET_WAITKIND_VFORK_DONE
:
3637 /* Done with the shared memory region. Re-insert breakpoints in
3638 the parent, and keep going. */
3641 fprintf_unfiltered (gdb_stdlog
,
3642 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3644 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3645 context_switch (ecs
->ptid
);
3647 current_inferior ()->waiting_for_vfork_done
= 0;
3648 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
3649 /* This also takes care of reinserting breakpoints in the
3650 previously locked inferior. */
3654 case TARGET_WAITKIND_EXECD
:
3656 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
3658 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3659 context_switch (ecs
->ptid
);
3661 singlestep_breakpoints_inserted_p
= 0;
3662 cancel_single_step_breakpoints ();
3664 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3666 /* Do whatever is necessary to the parent branch of the vfork. */
3667 handle_vfork_child_exec_or_exit (1);
3669 /* This causes the eventpoints and symbol table to be reset.
3670 Must do this now, before trying to determine whether to
3672 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
3674 ecs
->event_thread
->control
.stop_bpstat
3675 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3676 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3678 /* Note that this may be referenced from inside
3679 bpstat_stop_status above, through inferior_has_execd. */
3680 xfree (ecs
->ws
.value
.execd_pathname
);
3681 ecs
->ws
.value
.execd_pathname
= NULL
;
3683 /* If no catchpoint triggered for this, then keep going. */
3684 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3686 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3690 process_event_stop_test (ecs
);
3693 /* Be careful not to try to gather much state about a thread
3694 that's in a syscall. It's frequently a losing proposition. */
3695 case TARGET_WAITKIND_SYSCALL_ENTRY
:
3697 fprintf_unfiltered (gdb_stdlog
,
3698 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3699 /* Getting the current syscall number. */
3700 if (handle_syscall_event (ecs
) == 0)
3701 process_event_stop_test (ecs
);
3704 /* Before examining the threads further, step this thread to
3705 get it entirely out of the syscall. (We get notice of the
3706 event when the thread is just on the verge of exiting a
3707 syscall. Stepping one instruction seems to get it back
3709 case TARGET_WAITKIND_SYSCALL_RETURN
:
3711 fprintf_unfiltered (gdb_stdlog
,
3712 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3713 if (handle_syscall_event (ecs
) == 0)
3714 process_event_stop_test (ecs
);
3717 case TARGET_WAITKIND_STOPPED
:
3719 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
3720 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
3721 handle_signal_stop (ecs
);
3724 case TARGET_WAITKIND_NO_HISTORY
:
3726 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
3727 /* Reverse execution: target ran out of history info. */
3729 /* Pull the single step breakpoints out of the target. */
3730 if (singlestep_breakpoints_inserted_p
)
3732 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3733 context_switch (ecs
->ptid
);
3734 remove_single_step_breakpoints ();
3735 singlestep_breakpoints_inserted_p
= 0;
3737 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3738 print_no_history_reason ();
3739 stop_stepping (ecs
);
3744 /* Come here when the program has stopped with a signal. */
3747 handle_signal_stop (struct execution_control_state
*ecs
)
3749 struct frame_info
*frame
;
3750 struct gdbarch
*gdbarch
;
3751 int stopped_by_watchpoint
;
3752 enum stop_kind stop_soon
;
3755 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
3757 /* Do we need to clean up the state of a thread that has
3758 completed a displaced single-step? (Doing so usually affects
3759 the PC, so do it here, before we set stop_pc.) */
3760 displaced_step_fixup (ecs
->ptid
,
3761 ecs
->event_thread
->suspend
.stop_signal
);
3763 /* If we either finished a single-step or hit a breakpoint, but
3764 the user wanted this thread to be stopped, pretend we got a
3765 SIG0 (generic unsignaled stop). */
3767 if (ecs
->event_thread
->stop_requested
3768 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3769 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3772 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3776 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3777 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3778 struct cleanup
*old_chain
= save_inferior_ptid ();
3780 inferior_ptid
= ecs
->ptid
;
3782 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
3783 paddress (gdbarch
, stop_pc
));
3784 if (target_stopped_by_watchpoint ())
3788 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
3790 if (target_stopped_data_address (¤t_target
, &addr
))
3791 fprintf_unfiltered (gdb_stdlog
,
3792 "infrun: stopped data address = %s\n",
3793 paddress (gdbarch
, addr
));
3795 fprintf_unfiltered (gdb_stdlog
,
3796 "infrun: (no data address available)\n");
3799 do_cleanups (old_chain
);
3802 /* This is originated from start_remote(), start_inferior() and
3803 shared libraries hook functions. */
3804 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
3805 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
3807 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3808 context_switch (ecs
->ptid
);
3810 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3811 stop_print_frame
= 1;
3812 stop_stepping (ecs
);
3816 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
3819 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3820 context_switch (ecs
->ptid
);
3822 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
3823 stop_print_frame
= 0;
3824 stop_stepping (ecs
);
3828 /* This originates from attach_command(). We need to overwrite
3829 the stop_signal here, because some kernels don't ignore a
3830 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
3831 See more comments in inferior.h. On the other hand, if we
3832 get a non-SIGSTOP, report it to the user - assume the backend
3833 will handle the SIGSTOP if it should show up later.
3835 Also consider that the attach is complete when we see a
3836 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
3837 target extended-remote report it instead of a SIGSTOP
3838 (e.g. gdbserver). We already rely on SIGTRAP being our
3839 signal, so this is no exception.
3841 Also consider that the attach is complete when we see a
3842 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
3843 the target to stop all threads of the inferior, in case the
3844 low level attach operation doesn't stop them implicitly. If
3845 they weren't stopped implicitly, then the stub will report a
3846 GDB_SIGNAL_0, meaning: stopped for no particular reason
3847 other than GDB's request. */
3848 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3849 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
3850 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
3851 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
3853 stop_print_frame
= 1;
3854 stop_stepping (ecs
);
3855 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3859 if (stepping_past_singlestep_breakpoint
)
3861 gdb_assert (singlestep_breakpoints_inserted_p
);
3862 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
3863 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
3865 stepping_past_singlestep_breakpoint
= 0;
3867 /* We've either finished single-stepping past the single-step
3868 breakpoint, or stopped for some other reason. It would be nice if
3869 we could tell, but we can't reliably. */
3870 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3873 fprintf_unfiltered (gdb_stdlog
,
3874 "infrun: stepping_past_"
3875 "singlestep_breakpoint\n");
3876 /* Pull the single step breakpoints out of the target. */
3877 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3878 context_switch (ecs
->ptid
);
3879 remove_single_step_breakpoints ();
3880 singlestep_breakpoints_inserted_p
= 0;
3882 ecs
->event_thread
->control
.trap_expected
= 0;
3884 context_switch (saved_singlestep_ptid
);
3885 if (deprecated_context_hook
)
3886 deprecated_context_hook (pid_to_thread_id (saved_singlestep_ptid
));
3888 resume (1, GDB_SIGNAL_0
);
3889 prepare_to_wait (ecs
);
3894 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
3896 /* In non-stop mode, there's never a deferred_step_ptid set. */
3897 gdb_assert (!non_stop
);
3899 /* If we stopped for some other reason than single-stepping, ignore
3900 the fact that we were supposed to switch back. */
3901 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3904 fprintf_unfiltered (gdb_stdlog
,
3905 "infrun: handling deferred step\n");
3907 /* Pull the single step breakpoints out of the target. */
3908 if (singlestep_breakpoints_inserted_p
)
3910 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3911 context_switch (ecs
->ptid
);
3912 remove_single_step_breakpoints ();
3913 singlestep_breakpoints_inserted_p
= 0;
3916 ecs
->event_thread
->control
.trap_expected
= 0;
3918 context_switch (deferred_step_ptid
);
3919 deferred_step_ptid
= null_ptid
;
3920 /* Suppress spurious "Switching to ..." message. */
3921 previous_inferior_ptid
= inferior_ptid
;
3923 resume (1, GDB_SIGNAL_0
);
3924 prepare_to_wait (ecs
);
3928 deferred_step_ptid
= null_ptid
;
3931 /* See if a thread hit a thread-specific breakpoint that was meant for
3932 another thread. If so, then step that thread past the breakpoint,
3935 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3937 int thread_hop_needed
= 0;
3938 struct address_space
*aspace
=
3939 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
3941 /* Check if a regular breakpoint has been hit before checking
3942 for a potential single step breakpoint. Otherwise, GDB will
3943 not see this breakpoint hit when stepping onto breakpoints. */
3944 if (regular_breakpoint_inserted_here_p (aspace
, stop_pc
))
3946 if (!breakpoint_thread_match (aspace
, stop_pc
, ecs
->ptid
))
3947 thread_hop_needed
= 1;
3949 else if (singlestep_breakpoints_inserted_p
)
3951 /* We have not context switched yet, so this should be true
3952 no matter which thread hit the singlestep breakpoint. */
3953 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
3955 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
3957 target_pid_to_str (ecs
->ptid
));
3959 /* The call to in_thread_list is necessary because PTIDs sometimes
3960 change when we go from single-threaded to multi-threaded. If
3961 the singlestep_ptid is still in the list, assume that it is
3962 really different from ecs->ptid. */
3963 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
3964 && in_thread_list (singlestep_ptid
))
3966 /* If the PC of the thread we were trying to single-step
3967 has changed, discard this event (which we were going
3968 to ignore anyway), and pretend we saw that thread
3969 trap. This prevents us continuously moving the
3970 single-step breakpoint forward, one instruction at a
3971 time. If the PC has changed, then the thread we were
3972 trying to single-step has trapped or been signalled,
3973 but the event has not been reported to GDB yet.
3975 There might be some cases where this loses signal
3976 information, if a signal has arrived at exactly the
3977 same time that the PC changed, but this is the best
3978 we can do with the information available. Perhaps we
3979 should arrange to report all events for all threads
3980 when they stop, or to re-poll the remote looking for
3981 this particular thread (i.e. temporarily enable
3984 CORE_ADDR new_singlestep_pc
3985 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
3987 if (new_singlestep_pc
!= singlestep_pc
)
3989 enum gdb_signal stop_signal
;
3992 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
3993 " but expected thread advanced also\n");
3995 /* The current context still belongs to
3996 singlestep_ptid. Don't swap here, since that's
3997 the context we want to use. Just fudge our
3998 state and continue. */
3999 stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
4000 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4001 ecs
->ptid
= singlestep_ptid
;
4002 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4003 ecs
->event_thread
->suspend
.stop_signal
= stop_signal
;
4004 stop_pc
= new_singlestep_pc
;
4009 fprintf_unfiltered (gdb_stdlog
,
4010 "infrun: unexpected thread\n");
4012 thread_hop_needed
= 1;
4013 stepping_past_singlestep_breakpoint
= 1;
4014 saved_singlestep_ptid
= singlestep_ptid
;
4019 if (thread_hop_needed
)
4021 struct regcache
*thread_regcache
;
4022 int remove_status
= 0;
4025 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
4027 /* Switch context before touching inferior memory, the
4028 previous thread may have exited. */
4029 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
4030 context_switch (ecs
->ptid
);
4032 /* Saw a breakpoint, but it was hit by the wrong thread.
4035 if (singlestep_breakpoints_inserted_p
)
4037 /* Pull the single step breakpoints out of the target. */
4038 remove_single_step_breakpoints ();
4039 singlestep_breakpoints_inserted_p
= 0;
4042 /* If the arch can displace step, don't remove the
4044 thread_regcache
= get_thread_regcache (ecs
->ptid
);
4045 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
4046 remove_status
= remove_breakpoints ();
4048 /* Did we fail to remove breakpoints? If so, try
4049 to set the PC past the bp. (There's at least
4050 one situation in which we can fail to remove
4051 the bp's: On HP-UX's that use ttrace, we can't
4052 change the address space of a vforking child
4053 process until the child exits (well, okay, not
4054 then either :-) or execs. */
4055 if (remove_status
!= 0)
4056 error (_("Cannot step over breakpoint hit in wrong thread"));
4061 /* Only need to require the next event from this
4062 thread in all-stop mode. */
4063 waiton_ptid
= ecs
->ptid
;
4064 infwait_state
= infwait_thread_hop_state
;
4067 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4074 /* See if something interesting happened to the non-current thread. If
4075 so, then switch to that thread. */
4076 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4079 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
4081 context_switch (ecs
->ptid
);
4083 if (deprecated_context_hook
)
4084 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
4087 /* At this point, get hold of the now-current thread's frame. */
4088 frame
= get_current_frame ();
4089 gdbarch
= get_frame_arch (frame
);
4091 if (singlestep_breakpoints_inserted_p
)
4093 /* Pull the single step breakpoints out of the target. */
4094 remove_single_step_breakpoints ();
4095 singlestep_breakpoints_inserted_p
= 0;
4098 if (ecs
->stepped_after_stopped_by_watchpoint
)
4099 stopped_by_watchpoint
= 0;
4101 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
4103 /* If necessary, step over this watchpoint. We'll be back to display
4105 if (stopped_by_watchpoint
4106 && (target_have_steppable_watchpoint
4107 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4109 /* At this point, we are stopped at an instruction which has
4110 attempted to write to a piece of memory under control of
4111 a watchpoint. The instruction hasn't actually executed
4112 yet. If we were to evaluate the watchpoint expression
4113 now, we would get the old value, and therefore no change
4114 would seem to have occurred.
4116 In order to make watchpoints work `right', we really need
4117 to complete the memory write, and then evaluate the
4118 watchpoint expression. We do this by single-stepping the
4121 It may not be necessary to disable the watchpoint to stop over
4122 it. For example, the PA can (with some kernel cooperation)
4123 single step over a watchpoint without disabling the watchpoint.
4125 It is far more common to need to disable a watchpoint to step
4126 the inferior over it. If we have non-steppable watchpoints,
4127 we must disable the current watchpoint; it's simplest to
4128 disable all watchpoints and breakpoints. */
4131 if (!target_have_steppable_watchpoint
)
4133 remove_breakpoints ();
4134 /* See comment in resume why we need to stop bypassing signals
4135 while breakpoints have been removed. */
4136 target_pass_signals (0, NULL
);
4139 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
4140 target_resume (ecs
->ptid
, hw_step
, GDB_SIGNAL_0
);
4141 waiton_ptid
= ecs
->ptid
;
4142 if (target_have_steppable_watchpoint
)
4143 infwait_state
= infwait_step_watch_state
;
4145 infwait_state
= infwait_nonstep_watch_state
;
4146 prepare_to_wait (ecs
);
4150 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4151 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4152 ecs
->event_thread
->control
.stop_step
= 0;
4153 stop_print_frame
= 1;
4154 stopped_by_random_signal
= 0;
4156 /* Hide inlined functions starting here, unless we just performed stepi or
4157 nexti. After stepi and nexti, always show the innermost frame (not any
4158 inline function call sites). */
4159 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4161 struct address_space
*aspace
=
4162 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4164 /* skip_inline_frames is expensive, so we avoid it if we can
4165 determine that the address is one where functions cannot have
4166 been inlined. This improves performance with inferiors that
4167 load a lot of shared libraries, because the solib event
4168 breakpoint is defined as the address of a function (i.e. not
4169 inline). Note that we have to check the previous PC as well
4170 as the current one to catch cases when we have just
4171 single-stepped off a breakpoint prior to reinstating it.
4172 Note that we're assuming that the code we single-step to is
4173 not inline, but that's not definitive: there's nothing
4174 preventing the event breakpoint function from containing
4175 inlined code, and the single-step ending up there. If the
4176 user had set a breakpoint on that inlined code, the missing
4177 skip_inline_frames call would break things. Fortunately
4178 that's an extremely unlikely scenario. */
4179 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4180 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4181 && ecs
->event_thread
->control
.trap_expected
4182 && pc_at_non_inline_function (aspace
,
4183 ecs
->event_thread
->prev_pc
,
4186 skip_inline_frames (ecs
->ptid
);
4188 /* Re-fetch current thread's frame in case that invalidated
4190 frame
= get_current_frame ();
4191 gdbarch
= get_frame_arch (frame
);
4195 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4196 && ecs
->event_thread
->control
.trap_expected
4197 && gdbarch_single_step_through_delay_p (gdbarch
)
4198 && currently_stepping (ecs
->event_thread
))
4200 /* We're trying to step off a breakpoint. Turns out that we're
4201 also on an instruction that needs to be stepped multiple
4202 times before it's been fully executing. E.g., architectures
4203 with a delay slot. It needs to be stepped twice, once for
4204 the instruction and once for the delay slot. */
4205 int step_through_delay
4206 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4208 if (debug_infrun
&& step_through_delay
)
4209 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4210 if (ecs
->event_thread
->control
.step_range_end
== 0
4211 && step_through_delay
)
4213 /* The user issued a continue when stopped at a breakpoint.
4214 Set up for another trap and get out of here. */
4215 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4219 else if (step_through_delay
)
4221 /* The user issued a step when stopped at a breakpoint.
4222 Maybe we should stop, maybe we should not - the delay
4223 slot *might* correspond to a line of source. In any
4224 case, don't decide that here, just set
4225 ecs->stepping_over_breakpoint, making sure we
4226 single-step again before breakpoints are re-inserted. */
4227 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4231 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4232 handles this event. */
4233 ecs
->event_thread
->control
.stop_bpstat
4234 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4235 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4237 /* Following in case break condition called a
4239 stop_print_frame
= 1;
4241 /* This is where we handle "moribund" watchpoints. Unlike
4242 software breakpoints traps, hardware watchpoint traps are
4243 always distinguishable from random traps. If no high-level
4244 watchpoint is associated with the reported stop data address
4245 anymore, then the bpstat does not explain the signal ---
4246 simply make sure to ignore it if `stopped_by_watchpoint' is
4250 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4251 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4253 && stopped_by_watchpoint
)
4254 fprintf_unfiltered (gdb_stdlog
,
4255 "infrun: no user watchpoint explains "
4256 "watchpoint SIGTRAP, ignoring\n");
4258 /* NOTE: cagney/2003-03-29: These checks for a random signal
4259 at one stage in the past included checks for an inferior
4260 function call's call dummy's return breakpoint. The original
4261 comment, that went with the test, read:
4263 ``End of a stack dummy. Some systems (e.g. Sony news) give
4264 another signal besides SIGTRAP, so check here as well as
4267 If someone ever tries to get call dummys on a
4268 non-executable stack to work (where the target would stop
4269 with something like a SIGSEGV), then those tests might need
4270 to be re-instated. Given, however, that the tests were only
4271 enabled when momentary breakpoints were not being used, I
4272 suspect that it won't be the case.
4274 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4275 be necessary for call dummies on a non-executable stack on
4278 /* See if the breakpoints module can explain the signal. */
4280 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4281 ecs
->event_thread
->suspend
.stop_signal
);
4283 /* If not, perhaps stepping/nexting can. */
4285 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4286 && currently_stepping (ecs
->event_thread
));
4288 /* No? Perhaps we got a moribund watchpoint. */
4290 random_signal
= !stopped_by_watchpoint
;
4292 /* For the program's own signals, act according to
4293 the signal handling tables. */
4297 /* Signal not for debugging purposes. */
4299 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
4300 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
4303 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
4304 gdb_signal_to_symbol_string (stop_signal
));
4306 stopped_by_random_signal
= 1;
4308 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4311 target_terminal_ours_for_output ();
4312 print_signal_received_reason
4313 (ecs
->event_thread
->suspend
.stop_signal
);
4315 /* Always stop on signals if we're either just gaining control
4316 of the program, or the user explicitly requested this thread
4317 to remain stopped. */
4318 if (stop_soon
!= NO_STOP_QUIETLY
4319 || ecs
->event_thread
->stop_requested
4321 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4323 stop_stepping (ecs
);
4326 /* If not going to stop, give terminal back
4327 if we took it away. */
4329 target_terminal_inferior ();
4331 /* Clear the signal if it should not be passed. */
4332 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4333 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4335 if (ecs
->event_thread
->prev_pc
== stop_pc
4336 && ecs
->event_thread
->control
.trap_expected
4337 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4339 /* We were just starting a new sequence, attempting to
4340 single-step off of a breakpoint and expecting a SIGTRAP.
4341 Instead this signal arrives. This signal will take us out
4342 of the stepping range so GDB needs to remember to, when
4343 the signal handler returns, resume stepping off that
4345 /* To simplify things, "continue" is forced to use the same
4346 code paths as single-step - set a breakpoint at the
4347 signal return address and then, once hit, step off that
4350 fprintf_unfiltered (gdb_stdlog
,
4351 "infrun: signal arrived while stepping over "
4354 insert_hp_step_resume_breakpoint_at_frame (frame
);
4355 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4356 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4357 ecs
->event_thread
->control
.trap_expected
= 0;
4362 if (ecs
->event_thread
->control
.step_range_end
!= 0
4363 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4364 && pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4365 && frame_id_eq (get_stack_frame_id (frame
),
4366 ecs
->event_thread
->control
.step_stack_frame_id
)
4367 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4369 /* The inferior is about to take a signal that will take it
4370 out of the single step range. Set a breakpoint at the
4371 current PC (which is presumably where the signal handler
4372 will eventually return) and then allow the inferior to
4375 Note that this is only needed for a signal delivered
4376 while in the single-step range. Nested signals aren't a
4377 problem as they eventually all return. */
4379 fprintf_unfiltered (gdb_stdlog
,
4380 "infrun: signal may take us out of "
4381 "single-step range\n");
4383 insert_hp_step_resume_breakpoint_at_frame (frame
);
4384 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4385 ecs
->event_thread
->control
.trap_expected
= 0;
4390 /* Note: step_resume_breakpoint may be non-NULL. This occures
4391 when either there's a nested signal, or when there's a
4392 pending signal enabled just as the signal handler returns
4393 (leaving the inferior at the step-resume-breakpoint without
4394 actually executing it). Either way continue until the
4395 breakpoint is really hit. */
4397 if (!switch_back_to_stepped_thread (ecs
))
4400 fprintf_unfiltered (gdb_stdlog
,
4401 "infrun: random signal, keep going\n");
4408 process_event_stop_test (ecs
);
4411 /* Come here when we've got some debug event / signal we can explain
4412 (IOW, not a random signal), and test whether it should cause a
4413 stop, or whether we should resume the inferior (transparently).
4414 E.g., could be a breakpoint whose condition evaluates false; we
4415 could be still stepping within the line; etc. */
4418 process_event_stop_test (struct execution_control_state
*ecs
)
4420 struct symtab_and_line stop_pc_sal
;
4421 struct frame_info
*frame
;
4422 struct gdbarch
*gdbarch
;
4423 CORE_ADDR jmp_buf_pc
;
4424 struct bpstat_what what
;
4426 /* Handle cases caused by hitting a breakpoint. */
4428 frame
= get_current_frame ();
4429 gdbarch
= get_frame_arch (frame
);
4431 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4433 if (what
.call_dummy
)
4435 stop_stack_dummy
= what
.call_dummy
;
4438 /* If we hit an internal event that triggers symbol changes, the
4439 current frame will be invalidated within bpstat_what (e.g., if we
4440 hit an internal solib event). Re-fetch it. */
4441 frame
= get_current_frame ();
4442 gdbarch
= get_frame_arch (frame
);
4444 switch (what
.main_action
)
4446 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4447 /* If we hit the breakpoint at longjmp while stepping, we
4448 install a momentary breakpoint at the target of the
4452 fprintf_unfiltered (gdb_stdlog
,
4453 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4455 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4457 if (what
.is_longjmp
)
4459 struct value
*arg_value
;
4461 /* If we set the longjmp breakpoint via a SystemTap probe,
4462 then use it to extract the arguments. The destination PC
4463 is the third argument to the probe. */
4464 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4466 jmp_buf_pc
= value_as_address (arg_value
);
4467 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4468 || !gdbarch_get_longjmp_target (gdbarch
,
4469 frame
, &jmp_buf_pc
))
4472 fprintf_unfiltered (gdb_stdlog
,
4473 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4474 "(!gdbarch_get_longjmp_target)\n");
4479 /* Insert a breakpoint at resume address. */
4480 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4483 check_exception_resume (ecs
, frame
);
4487 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4489 struct frame_info
*init_frame
;
4491 /* There are several cases to consider.
4493 1. The initiating frame no longer exists. In this case we
4494 must stop, because the exception or longjmp has gone too
4497 2. The initiating frame exists, and is the same as the
4498 current frame. We stop, because the exception or longjmp
4501 3. The initiating frame exists and is different from the
4502 current frame. This means the exception or longjmp has
4503 been caught beneath the initiating frame, so keep going.
4505 4. longjmp breakpoint has been placed just to protect
4506 against stale dummy frames and user is not interested in
4507 stopping around longjmps. */
4510 fprintf_unfiltered (gdb_stdlog
,
4511 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4513 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4515 delete_exception_resume_breakpoint (ecs
->event_thread
);
4517 if (what
.is_longjmp
)
4519 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
->num
);
4521 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
4529 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4533 struct frame_id current_id
4534 = get_frame_id (get_current_frame ());
4535 if (frame_id_eq (current_id
,
4536 ecs
->event_thread
->initiating_frame
))
4538 /* Case 2. Fall through. */
4548 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
4550 delete_step_resume_breakpoint (ecs
->event_thread
);
4552 ecs
->event_thread
->control
.stop_step
= 1;
4553 print_end_stepping_range_reason ();
4554 stop_stepping (ecs
);
4558 case BPSTAT_WHAT_SINGLE
:
4560 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4561 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4562 /* Still need to check other stuff, at least the case where we
4563 are stepping and step out of the right range. */
4566 case BPSTAT_WHAT_STEP_RESUME
:
4568 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4570 delete_step_resume_breakpoint (ecs
->event_thread
);
4571 if (ecs
->event_thread
->control
.proceed_to_finish
4572 && execution_direction
== EXEC_REVERSE
)
4574 struct thread_info
*tp
= ecs
->event_thread
;
4576 /* We are finishing a function in reverse, and just hit the
4577 step-resume breakpoint at the start address of the
4578 function, and we're almost there -- just need to back up
4579 by one more single-step, which should take us back to the
4581 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4585 fill_in_stop_func (gdbarch
, ecs
);
4586 if (stop_pc
== ecs
->stop_func_start
4587 && execution_direction
== EXEC_REVERSE
)
4589 /* We are stepping over a function call in reverse, and just
4590 hit the step-resume breakpoint at the start address of
4591 the function. Go back to single-stepping, which should
4592 take us back to the function call. */
4593 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4599 case BPSTAT_WHAT_STOP_NOISY
:
4601 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4602 stop_print_frame
= 1;
4604 /* We are about to nuke the step_resume_breakpointt via the
4605 cleanup chain, so no need to worry about it here. */
4607 stop_stepping (ecs
);
4610 case BPSTAT_WHAT_STOP_SILENT
:
4612 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4613 stop_print_frame
= 0;
4615 /* We are about to nuke the step_resume_breakpoin via the
4616 cleanup chain, so no need to worry about it here. */
4618 stop_stepping (ecs
);
4621 case BPSTAT_WHAT_HP_STEP_RESUME
:
4623 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4625 delete_step_resume_breakpoint (ecs
->event_thread
);
4626 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4628 /* Back when the step-resume breakpoint was inserted, we
4629 were trying to single-step off a breakpoint. Go back to
4631 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4632 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4638 case BPSTAT_WHAT_KEEP_CHECKING
:
4642 /* We come here if we hit a breakpoint but should not stop for it.
4643 Possibly we also were stepping and should stop for that. So fall
4644 through and test for stepping. But, if not stepping, do not
4647 /* In all-stop mode, if we're currently stepping but have stopped in
4648 some other thread, we need to switch back to the stepped thread. */
4649 if (switch_back_to_stepped_thread (ecs
))
4652 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4655 fprintf_unfiltered (gdb_stdlog
,
4656 "infrun: step-resume breakpoint is inserted\n");
4658 /* Having a step-resume breakpoint overrides anything
4659 else having to do with stepping commands until
4660 that breakpoint is reached. */
4665 if (ecs
->event_thread
->control
.step_range_end
== 0)
4668 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4669 /* Likewise if we aren't even stepping. */
4674 /* Re-fetch current thread's frame in case the code above caused
4675 the frame cache to be re-initialized, making our FRAME variable
4676 a dangling pointer. */
4677 frame
= get_current_frame ();
4678 gdbarch
= get_frame_arch (frame
);
4679 fill_in_stop_func (gdbarch
, ecs
);
4681 /* If stepping through a line, keep going if still within it.
4683 Note that step_range_end is the address of the first instruction
4684 beyond the step range, and NOT the address of the last instruction
4687 Note also that during reverse execution, we may be stepping
4688 through a function epilogue and therefore must detect when
4689 the current-frame changes in the middle of a line. */
4691 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4692 && (execution_direction
!= EXEC_REVERSE
4693 || frame_id_eq (get_frame_id (frame
),
4694 ecs
->event_thread
->control
.step_frame_id
)))
4698 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4699 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4700 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4702 /* Tentatively re-enable range stepping; `resume' disables it if
4703 necessary (e.g., if we're stepping over a breakpoint or we
4704 have software watchpoints). */
4705 ecs
->event_thread
->control
.may_range_step
= 1;
4707 /* When stepping backward, stop at beginning of line range
4708 (unless it's the function entry point, in which case
4709 keep going back to the call point). */
4710 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4711 && stop_pc
!= ecs
->stop_func_start
4712 && execution_direction
== EXEC_REVERSE
)
4714 ecs
->event_thread
->control
.stop_step
= 1;
4715 print_end_stepping_range_reason ();
4716 stop_stepping (ecs
);
4724 /* We stepped out of the stepping range. */
4726 /* If we are stepping at the source level and entered the runtime
4727 loader dynamic symbol resolution code...
4729 EXEC_FORWARD: we keep on single stepping until we exit the run
4730 time loader code and reach the callee's address.
4732 EXEC_REVERSE: we've already executed the callee (backward), and
4733 the runtime loader code is handled just like any other
4734 undebuggable function call. Now we need only keep stepping
4735 backward through the trampoline code, and that's handled further
4736 down, so there is nothing for us to do here. */
4738 if (execution_direction
!= EXEC_REVERSE
4739 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4740 && in_solib_dynsym_resolve_code (stop_pc
))
4742 CORE_ADDR pc_after_resolver
=
4743 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4746 fprintf_unfiltered (gdb_stdlog
,
4747 "infrun: stepped into dynsym resolve code\n");
4749 if (pc_after_resolver
)
4751 /* Set up a step-resume breakpoint at the address
4752 indicated by SKIP_SOLIB_RESOLVER. */
4753 struct symtab_and_line sr_sal
;
4756 sr_sal
.pc
= pc_after_resolver
;
4757 sr_sal
.pspace
= get_frame_program_space (frame
);
4759 insert_step_resume_breakpoint_at_sal (gdbarch
,
4760 sr_sal
, null_frame_id
);
4767 if (ecs
->event_thread
->control
.step_range_end
!= 1
4768 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4769 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4770 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
4773 fprintf_unfiltered (gdb_stdlog
,
4774 "infrun: stepped into signal trampoline\n");
4775 /* The inferior, while doing a "step" or "next", has ended up in
4776 a signal trampoline (either by a signal being delivered or by
4777 the signal handler returning). Just single-step until the
4778 inferior leaves the trampoline (either by calling the handler
4784 /* If we're in the return path from a shared library trampoline,
4785 we want to proceed through the trampoline when stepping. */
4786 /* macro/2012-04-25: This needs to come before the subroutine
4787 call check below as on some targets return trampolines look
4788 like subroutine calls (MIPS16 return thunks). */
4789 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4790 stop_pc
, ecs
->stop_func_name
)
4791 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
4793 /* Determine where this trampoline returns. */
4794 CORE_ADDR real_stop_pc
;
4796 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4799 fprintf_unfiltered (gdb_stdlog
,
4800 "infrun: stepped into solib return tramp\n");
4802 /* Only proceed through if we know where it's going. */
4805 /* And put the step-breakpoint there and go until there. */
4806 struct symtab_and_line sr_sal
;
4808 init_sal (&sr_sal
); /* initialize to zeroes */
4809 sr_sal
.pc
= real_stop_pc
;
4810 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4811 sr_sal
.pspace
= get_frame_program_space (frame
);
4813 /* Do not specify what the fp should be when we stop since
4814 on some machines the prologue is where the new fp value
4816 insert_step_resume_breakpoint_at_sal (gdbarch
,
4817 sr_sal
, null_frame_id
);
4819 /* Restart without fiddling with the step ranges or
4826 /* Check for subroutine calls. The check for the current frame
4827 equalling the step ID is not necessary - the check of the
4828 previous frame's ID is sufficient - but it is a common case and
4829 cheaper than checking the previous frame's ID.
4831 NOTE: frame_id_eq will never report two invalid frame IDs as
4832 being equal, so to get into this block, both the current and
4833 previous frame must have valid frame IDs. */
4834 /* The outer_frame_id check is a heuristic to detect stepping
4835 through startup code. If we step over an instruction which
4836 sets the stack pointer from an invalid value to a valid value,
4837 we may detect that as a subroutine call from the mythical
4838 "outermost" function. This could be fixed by marking
4839 outermost frames as !stack_p,code_p,special_p. Then the
4840 initial outermost frame, before sp was valid, would
4841 have code_addr == &_start. See the comment in frame_id_eq
4843 if (!frame_id_eq (get_stack_frame_id (frame
),
4844 ecs
->event_thread
->control
.step_stack_frame_id
)
4845 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4846 ecs
->event_thread
->control
.step_stack_frame_id
)
4847 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
4849 || step_start_function
!= find_pc_function (stop_pc
))))
4851 CORE_ADDR real_stop_pc
;
4854 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
4856 if ((ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
4857 || ((ecs
->event_thread
->control
.step_range_end
== 1)
4858 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
4859 ecs
->stop_func_start
)))
4861 /* I presume that step_over_calls is only 0 when we're
4862 supposed to be stepping at the assembly language level
4863 ("stepi"). Just stop. */
4864 /* Also, maybe we just did a "nexti" inside a prolog, so we
4865 thought it was a subroutine call but it was not. Stop as
4867 /* And this works the same backward as frontward. MVS */
4868 ecs
->event_thread
->control
.stop_step
= 1;
4869 print_end_stepping_range_reason ();
4870 stop_stepping (ecs
);
4874 /* Reverse stepping through solib trampolines. */
4876 if (execution_direction
== EXEC_REVERSE
4877 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
4878 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4879 || (ecs
->stop_func_start
== 0
4880 && in_solib_dynsym_resolve_code (stop_pc
))))
4882 /* Any solib trampoline code can be handled in reverse
4883 by simply continuing to single-step. We have already
4884 executed the solib function (backwards), and a few
4885 steps will take us back through the trampoline to the
4891 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4893 /* We're doing a "next".
4895 Normal (forward) execution: set a breakpoint at the
4896 callee's return address (the address at which the caller
4899 Reverse (backward) execution. set the step-resume
4900 breakpoint at the start of the function that we just
4901 stepped into (backwards), and continue to there. When we
4902 get there, we'll need to single-step back to the caller. */
4904 if (execution_direction
== EXEC_REVERSE
)
4906 /* If we're already at the start of the function, we've either
4907 just stepped backward into a single instruction function,
4908 or stepped back out of a signal handler to the first instruction
4909 of the function. Just keep going, which will single-step back
4911 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
4913 struct symtab_and_line sr_sal
;
4915 /* Normal function call return (static or dynamic). */
4917 sr_sal
.pc
= ecs
->stop_func_start
;
4918 sr_sal
.pspace
= get_frame_program_space (frame
);
4919 insert_step_resume_breakpoint_at_sal (gdbarch
,
4920 sr_sal
, null_frame_id
);
4924 insert_step_resume_breakpoint_at_caller (frame
);
4930 /* If we are in a function call trampoline (a stub between the
4931 calling routine and the real function), locate the real
4932 function. That's what tells us (a) whether we want to step
4933 into it at all, and (b) what prologue we want to run to the
4934 end of, if we do step into it. */
4935 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
4936 if (real_stop_pc
== 0)
4937 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4938 if (real_stop_pc
!= 0)
4939 ecs
->stop_func_start
= real_stop_pc
;
4941 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
4943 struct symtab_and_line sr_sal
;
4946 sr_sal
.pc
= ecs
->stop_func_start
;
4947 sr_sal
.pspace
= get_frame_program_space (frame
);
4949 insert_step_resume_breakpoint_at_sal (gdbarch
,
4950 sr_sal
, null_frame_id
);
4955 /* If we have line number information for the function we are
4956 thinking of stepping into and the function isn't on the skip
4959 If there are several symtabs at that PC (e.g. with include
4960 files), just want to know whether *any* of them have line
4961 numbers. find_pc_line handles this. */
4963 struct symtab_and_line tmp_sal
;
4965 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4966 if (tmp_sal
.line
!= 0
4967 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
4970 if (execution_direction
== EXEC_REVERSE
)
4971 handle_step_into_function_backward (gdbarch
, ecs
);
4973 handle_step_into_function (gdbarch
, ecs
);
4978 /* If we have no line number and the step-stop-if-no-debug is
4979 set, we stop the step so that the user has a chance to switch
4980 in assembly mode. */
4981 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4982 && step_stop_if_no_debug
)
4984 ecs
->event_thread
->control
.stop_step
= 1;
4985 print_end_stepping_range_reason ();
4986 stop_stepping (ecs
);
4990 if (execution_direction
== EXEC_REVERSE
)
4992 /* If we're already at the start of the function, we've either just
4993 stepped backward into a single instruction function without line
4994 number info, or stepped back out of a signal handler to the first
4995 instruction of the function without line number info. Just keep
4996 going, which will single-step back to the caller. */
4997 if (ecs
->stop_func_start
!= stop_pc
)
4999 /* Set a breakpoint at callee's start address.
5000 From there we can step once and be back in the caller. */
5001 struct symtab_and_line sr_sal
;
5004 sr_sal
.pc
= ecs
->stop_func_start
;
5005 sr_sal
.pspace
= get_frame_program_space (frame
);
5006 insert_step_resume_breakpoint_at_sal (gdbarch
,
5007 sr_sal
, null_frame_id
);
5011 /* Set a breakpoint at callee's return address (the address
5012 at which the caller will resume). */
5013 insert_step_resume_breakpoint_at_caller (frame
);
5019 /* Reverse stepping through solib trampolines. */
5021 if (execution_direction
== EXEC_REVERSE
5022 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5024 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5025 || (ecs
->stop_func_start
== 0
5026 && in_solib_dynsym_resolve_code (stop_pc
)))
5028 /* Any solib trampoline code can be handled in reverse
5029 by simply continuing to single-step. We have already
5030 executed the solib function (backwards), and a few
5031 steps will take us back through the trampoline to the
5036 else if (in_solib_dynsym_resolve_code (stop_pc
))
5038 /* Stepped backward into the solib dynsym resolver.
5039 Set a breakpoint at its start and continue, then
5040 one more step will take us out. */
5041 struct symtab_and_line sr_sal
;
5044 sr_sal
.pc
= ecs
->stop_func_start
;
5045 sr_sal
.pspace
= get_frame_program_space (frame
);
5046 insert_step_resume_breakpoint_at_sal (gdbarch
,
5047 sr_sal
, null_frame_id
);
5053 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5055 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5056 the trampoline processing logic, however, there are some trampolines
5057 that have no names, so we should do trampoline handling first. */
5058 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5059 && ecs
->stop_func_name
== NULL
5060 && stop_pc_sal
.line
== 0)
5063 fprintf_unfiltered (gdb_stdlog
,
5064 "infrun: stepped into undebuggable function\n");
5066 /* The inferior just stepped into, or returned to, an
5067 undebuggable function (where there is no debugging information
5068 and no line number corresponding to the address where the
5069 inferior stopped). Since we want to skip this kind of code,
5070 we keep going until the inferior returns from this
5071 function - unless the user has asked us not to (via
5072 set step-mode) or we no longer know how to get back
5073 to the call site. */
5074 if (step_stop_if_no_debug
5075 || !frame_id_p (frame_unwind_caller_id (frame
)))
5077 /* If we have no line number and the step-stop-if-no-debug
5078 is set, we stop the step so that the user has a chance to
5079 switch in assembly mode. */
5080 ecs
->event_thread
->control
.stop_step
= 1;
5081 print_end_stepping_range_reason ();
5082 stop_stepping (ecs
);
5087 /* Set a breakpoint at callee's return address (the address
5088 at which the caller will resume). */
5089 insert_step_resume_breakpoint_at_caller (frame
);
5095 if (ecs
->event_thread
->control
.step_range_end
== 1)
5097 /* It is stepi or nexti. We always want to stop stepping after
5100 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5101 ecs
->event_thread
->control
.stop_step
= 1;
5102 print_end_stepping_range_reason ();
5103 stop_stepping (ecs
);
5107 if (stop_pc_sal
.line
== 0)
5109 /* We have no line number information. That means to stop
5110 stepping (does this always happen right after one instruction,
5111 when we do "s" in a function with no line numbers,
5112 or can this happen as a result of a return or longjmp?). */
5114 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5115 ecs
->event_thread
->control
.stop_step
= 1;
5116 print_end_stepping_range_reason ();
5117 stop_stepping (ecs
);
5121 /* Look for "calls" to inlined functions, part one. If the inline
5122 frame machinery detected some skipped call sites, we have entered
5123 a new inline function. */
5125 if (frame_id_eq (get_frame_id (get_current_frame ()),
5126 ecs
->event_thread
->control
.step_frame_id
)
5127 && inline_skipped_frames (ecs
->ptid
))
5129 struct symtab_and_line call_sal
;
5132 fprintf_unfiltered (gdb_stdlog
,
5133 "infrun: stepped into inlined function\n");
5135 find_frame_sal (get_current_frame (), &call_sal
);
5137 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5139 /* For "step", we're going to stop. But if the call site
5140 for this inlined function is on the same source line as
5141 we were previously stepping, go down into the function
5142 first. Otherwise stop at the call site. */
5144 if (call_sal
.line
== ecs
->event_thread
->current_line
5145 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5146 step_into_inline_frame (ecs
->ptid
);
5148 ecs
->event_thread
->control
.stop_step
= 1;
5149 print_end_stepping_range_reason ();
5150 stop_stepping (ecs
);
5155 /* For "next", we should stop at the call site if it is on a
5156 different source line. Otherwise continue through the
5157 inlined function. */
5158 if (call_sal
.line
== ecs
->event_thread
->current_line
5159 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5163 ecs
->event_thread
->control
.stop_step
= 1;
5164 print_end_stepping_range_reason ();
5165 stop_stepping (ecs
);
5171 /* Look for "calls" to inlined functions, part two. If we are still
5172 in the same real function we were stepping through, but we have
5173 to go further up to find the exact frame ID, we are stepping
5174 through a more inlined call beyond its call site. */
5176 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5177 && !frame_id_eq (get_frame_id (get_current_frame ()),
5178 ecs
->event_thread
->control
.step_frame_id
)
5179 && stepped_in_from (get_current_frame (),
5180 ecs
->event_thread
->control
.step_frame_id
))
5183 fprintf_unfiltered (gdb_stdlog
,
5184 "infrun: stepping through inlined function\n");
5186 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5190 ecs
->event_thread
->control
.stop_step
= 1;
5191 print_end_stepping_range_reason ();
5192 stop_stepping (ecs
);
5197 if ((stop_pc
== stop_pc_sal
.pc
)
5198 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5199 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5201 /* We are at the start of a different line. So stop. Note that
5202 we don't stop if we step into the middle of a different line.
5203 That is said to make things like for (;;) statements work
5206 fprintf_unfiltered (gdb_stdlog
,
5207 "infrun: stepped to a different line\n");
5208 ecs
->event_thread
->control
.stop_step
= 1;
5209 print_end_stepping_range_reason ();
5210 stop_stepping (ecs
);
5214 /* We aren't done stepping.
5216 Optimize by setting the stepping range to the line.
5217 (We might not be in the original line, but if we entered a
5218 new line in mid-statement, we continue stepping. This makes
5219 things like for(;;) statements work better.) */
5221 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5222 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5223 ecs
->event_thread
->control
.may_range_step
= 1;
5224 set_step_info (frame
, stop_pc_sal
);
5227 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5231 /* In all-stop mode, if we're currently stepping but have stopped in
5232 some other thread, we may need to switch back to the stepped
5233 thread. Returns true we set the inferior running, false if we left
5234 it stopped (and the event needs further processing). */
5237 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
5241 struct thread_info
*tp
;
5243 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
5247 /* However, if the current thread is blocked on some internal
5248 breakpoint, and we simply need to step over that breakpoint
5249 to get it going again, do that first. */
5250 if ((ecs
->event_thread
->control
.trap_expected
5251 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5252 || ecs
->event_thread
->stepping_over_breakpoint
)
5258 /* If the stepping thread exited, then don't try to switch
5259 back and resume it, which could fail in several different
5260 ways depending on the target. Instead, just keep going.
5262 We can find a stepping dead thread in the thread list in
5265 - The target supports thread exit events, and when the
5266 target tries to delete the thread from the thread list,
5267 inferior_ptid pointed at the exiting thread. In such
5268 case, calling delete_thread does not really remove the
5269 thread from the list; instead, the thread is left listed,
5270 with 'exited' state.
5272 - The target's debug interface does not support thread
5273 exit events, and so we have no idea whatsoever if the
5274 previously stepping thread is still alive. For that
5275 reason, we need to synchronously query the target
5277 if (is_exited (tp
->ptid
)
5278 || !target_thread_alive (tp
->ptid
))
5281 fprintf_unfiltered (gdb_stdlog
,
5282 "infrun: not switching back to "
5283 "stepped thread, it has vanished\n");
5285 delete_thread (tp
->ptid
);
5290 /* Otherwise, we no longer expect a trap in the current thread.
5291 Clear the trap_expected flag before switching back -- this is
5292 what keep_going would do as well, if we called it. */
5293 ecs
->event_thread
->control
.trap_expected
= 0;
5296 fprintf_unfiltered (gdb_stdlog
,
5297 "infrun: switching back to stepped thread\n");
5299 ecs
->event_thread
= tp
;
5300 ecs
->ptid
= tp
->ptid
;
5301 context_switch (ecs
->ptid
);
5309 /* Is thread TP in the middle of single-stepping? */
5312 currently_stepping (struct thread_info
*tp
)
5314 return ((tp
->control
.step_range_end
5315 && tp
->control
.step_resume_breakpoint
== NULL
)
5316 || tp
->control
.trap_expected
5317 || bpstat_should_step ());
5320 /* Returns true if any thread *but* the one passed in "data" is in the
5321 middle of stepping or of handling a "next". */
5324 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
5329 return (tp
->control
.step_range_end
5330 || tp
->control
.trap_expected
);
5333 /* Inferior has stepped into a subroutine call with source code that
5334 we should not step over. Do step to the first line of code in
5338 handle_step_into_function (struct gdbarch
*gdbarch
,
5339 struct execution_control_state
*ecs
)
5342 struct symtab_and_line stop_func_sal
, sr_sal
;
5344 fill_in_stop_func (gdbarch
, ecs
);
5346 s
= find_pc_symtab (stop_pc
);
5347 if (s
&& s
->language
!= language_asm
)
5348 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5349 ecs
->stop_func_start
);
5351 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5352 /* Use the step_resume_break to step until the end of the prologue,
5353 even if that involves jumps (as it seems to on the vax under
5355 /* If the prologue ends in the middle of a source line, continue to
5356 the end of that source line (if it is still within the function).
5357 Otherwise, just go to end of prologue. */
5358 if (stop_func_sal
.end
5359 && stop_func_sal
.pc
!= ecs
->stop_func_start
5360 && stop_func_sal
.end
< ecs
->stop_func_end
)
5361 ecs
->stop_func_start
= stop_func_sal
.end
;
5363 /* Architectures which require breakpoint adjustment might not be able
5364 to place a breakpoint at the computed address. If so, the test
5365 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5366 ecs->stop_func_start to an address at which a breakpoint may be
5367 legitimately placed.
5369 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5370 made, GDB will enter an infinite loop when stepping through
5371 optimized code consisting of VLIW instructions which contain
5372 subinstructions corresponding to different source lines. On
5373 FR-V, it's not permitted to place a breakpoint on any but the
5374 first subinstruction of a VLIW instruction. When a breakpoint is
5375 set, GDB will adjust the breakpoint address to the beginning of
5376 the VLIW instruction. Thus, we need to make the corresponding
5377 adjustment here when computing the stop address. */
5379 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5381 ecs
->stop_func_start
5382 = gdbarch_adjust_breakpoint_address (gdbarch
,
5383 ecs
->stop_func_start
);
5386 if (ecs
->stop_func_start
== stop_pc
)
5388 /* We are already there: stop now. */
5389 ecs
->event_thread
->control
.stop_step
= 1;
5390 print_end_stepping_range_reason ();
5391 stop_stepping (ecs
);
5396 /* Put the step-breakpoint there and go until there. */
5397 init_sal (&sr_sal
); /* initialize to zeroes */
5398 sr_sal
.pc
= ecs
->stop_func_start
;
5399 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5400 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5402 /* Do not specify what the fp should be when we stop since on
5403 some machines the prologue is where the new fp value is
5405 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5407 /* And make sure stepping stops right away then. */
5408 ecs
->event_thread
->control
.step_range_end
5409 = ecs
->event_thread
->control
.step_range_start
;
5414 /* Inferior has stepped backward into a subroutine call with source
5415 code that we should not step over. Do step to the beginning of the
5416 last line of code in it. */
5419 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5420 struct execution_control_state
*ecs
)
5423 struct symtab_and_line stop_func_sal
;
5425 fill_in_stop_func (gdbarch
, ecs
);
5427 s
= find_pc_symtab (stop_pc
);
5428 if (s
&& s
->language
!= language_asm
)
5429 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5430 ecs
->stop_func_start
);
5432 stop_func_sal
= find_pc_line (stop_pc
, 0);
5434 /* OK, we're just going to keep stepping here. */
5435 if (stop_func_sal
.pc
== stop_pc
)
5437 /* We're there already. Just stop stepping now. */
5438 ecs
->event_thread
->control
.stop_step
= 1;
5439 print_end_stepping_range_reason ();
5440 stop_stepping (ecs
);
5444 /* Else just reset the step range and keep going.
5445 No step-resume breakpoint, they don't work for
5446 epilogues, which can have multiple entry paths. */
5447 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5448 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5454 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5455 This is used to both functions and to skip over code. */
5458 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5459 struct symtab_and_line sr_sal
,
5460 struct frame_id sr_id
,
5461 enum bptype sr_type
)
5463 /* There should never be more than one step-resume or longjmp-resume
5464 breakpoint per thread, so we should never be setting a new
5465 step_resume_breakpoint when one is already active. */
5466 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5467 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5470 fprintf_unfiltered (gdb_stdlog
,
5471 "infrun: inserting step-resume breakpoint at %s\n",
5472 paddress (gdbarch
, sr_sal
.pc
));
5474 inferior_thread ()->control
.step_resume_breakpoint
5475 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5479 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5480 struct symtab_and_line sr_sal
,
5481 struct frame_id sr_id
)
5483 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5488 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5489 This is used to skip a potential signal handler.
5491 This is called with the interrupted function's frame. The signal
5492 handler, when it returns, will resume the interrupted function at
5496 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5498 struct symtab_and_line sr_sal
;
5499 struct gdbarch
*gdbarch
;
5501 gdb_assert (return_frame
!= NULL
);
5502 init_sal (&sr_sal
); /* initialize to zeros */
5504 gdbarch
= get_frame_arch (return_frame
);
5505 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5506 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5507 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5509 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5510 get_stack_frame_id (return_frame
),
5514 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5515 is used to skip a function after stepping into it (for "next" or if
5516 the called function has no debugging information).
5518 The current function has almost always been reached by single
5519 stepping a call or return instruction. NEXT_FRAME belongs to the
5520 current function, and the breakpoint will be set at the caller's
5523 This is a separate function rather than reusing
5524 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5525 get_prev_frame, which may stop prematurely (see the implementation
5526 of frame_unwind_caller_id for an example). */
5529 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5531 struct symtab_and_line sr_sal
;
5532 struct gdbarch
*gdbarch
;
5534 /* We shouldn't have gotten here if we don't know where the call site
5536 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5538 init_sal (&sr_sal
); /* initialize to zeros */
5540 gdbarch
= frame_unwind_caller_arch (next_frame
);
5541 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5542 frame_unwind_caller_pc (next_frame
));
5543 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5544 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5546 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5547 frame_unwind_caller_id (next_frame
));
5550 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5551 new breakpoint at the target of a jmp_buf. The handling of
5552 longjmp-resume uses the same mechanisms used for handling
5553 "step-resume" breakpoints. */
5556 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5558 /* There should never be more than one longjmp-resume breakpoint per
5559 thread, so we should never be setting a new
5560 longjmp_resume_breakpoint when one is already active. */
5561 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
5564 fprintf_unfiltered (gdb_stdlog
,
5565 "infrun: inserting longjmp-resume breakpoint at %s\n",
5566 paddress (gdbarch
, pc
));
5568 inferior_thread ()->control
.exception_resume_breakpoint
=
5569 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5572 /* Insert an exception resume breakpoint. TP is the thread throwing
5573 the exception. The block B is the block of the unwinder debug hook
5574 function. FRAME is the frame corresponding to the call to this
5575 function. SYM is the symbol of the function argument holding the
5576 target PC of the exception. */
5579 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5581 struct frame_info
*frame
,
5584 volatile struct gdb_exception e
;
5586 /* We want to ignore errors here. */
5587 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5589 struct symbol
*vsym
;
5590 struct value
*value
;
5592 struct breakpoint
*bp
;
5594 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5595 value
= read_var_value (vsym
, frame
);
5596 /* If the value was optimized out, revert to the old behavior. */
5597 if (! value_optimized_out (value
))
5599 handler
= value_as_address (value
);
5602 fprintf_unfiltered (gdb_stdlog
,
5603 "infrun: exception resume at %lx\n",
5604 (unsigned long) handler
);
5606 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5607 handler
, bp_exception_resume
);
5609 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5612 bp
->thread
= tp
->num
;
5613 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5618 /* A helper for check_exception_resume that sets an
5619 exception-breakpoint based on a SystemTap probe. */
5622 insert_exception_resume_from_probe (struct thread_info
*tp
,
5623 const struct probe
*probe
,
5624 struct frame_info
*frame
)
5626 struct value
*arg_value
;
5628 struct breakpoint
*bp
;
5630 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
5634 handler
= value_as_address (arg_value
);
5637 fprintf_unfiltered (gdb_stdlog
,
5638 "infrun: exception resume at %s\n",
5639 paddress (get_objfile_arch (probe
->objfile
),
5642 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5643 handler
, bp_exception_resume
);
5644 bp
->thread
= tp
->num
;
5645 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5648 /* This is called when an exception has been intercepted. Check to
5649 see whether the exception's destination is of interest, and if so,
5650 set an exception resume breakpoint there. */
5653 check_exception_resume (struct execution_control_state
*ecs
,
5654 struct frame_info
*frame
)
5656 volatile struct gdb_exception e
;
5657 const struct probe
*probe
;
5658 struct symbol
*func
;
5660 /* First see if this exception unwinding breakpoint was set via a
5661 SystemTap probe point. If so, the probe has two arguments: the
5662 CFA and the HANDLER. We ignore the CFA, extract the handler, and
5663 set a breakpoint there. */
5664 probe
= find_probe_by_pc (get_frame_pc (frame
));
5667 insert_exception_resume_from_probe (ecs
->event_thread
, probe
, frame
);
5671 func
= get_frame_function (frame
);
5675 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5678 struct block_iterator iter
;
5682 /* The exception breakpoint is a thread-specific breakpoint on
5683 the unwinder's debug hook, declared as:
5685 void _Unwind_DebugHook (void *cfa, void *handler);
5687 The CFA argument indicates the frame to which control is
5688 about to be transferred. HANDLER is the destination PC.
5690 We ignore the CFA and set a temporary breakpoint at HANDLER.
5691 This is not extremely efficient but it avoids issues in gdb
5692 with computing the DWARF CFA, and it also works even in weird
5693 cases such as throwing an exception from inside a signal
5696 b
= SYMBOL_BLOCK_VALUE (func
);
5697 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
5699 if (!SYMBOL_IS_ARGUMENT (sym
))
5706 insert_exception_resume_breakpoint (ecs
->event_thread
,
5715 stop_stepping (struct execution_control_state
*ecs
)
5718 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
5720 /* Let callers know we don't want to wait for the inferior anymore. */
5721 ecs
->wait_some_more
= 0;
5724 /* Called when we should continue running the inferior, because the
5725 current event doesn't cause a user visible stop. This does the
5726 resuming part; waiting for the next event is done elsewhere. */
5729 keep_going (struct execution_control_state
*ecs
)
5731 /* Make sure normal_stop is called if we get a QUIT handled before
5733 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
5735 /* Save the pc before execution, to compare with pc after stop. */
5736 ecs
->event_thread
->prev_pc
5737 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5739 if (ecs
->event_thread
->control
.trap_expected
5740 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5742 /* We haven't yet gotten our trap, and either: intercepted a
5743 non-signal event (e.g., a fork); or took a signal which we
5744 are supposed to pass through to the inferior. Simply
5746 discard_cleanups (old_cleanups
);
5747 resume (currently_stepping (ecs
->event_thread
),
5748 ecs
->event_thread
->suspend
.stop_signal
);
5752 /* Either the trap was not expected, but we are continuing
5753 anyway (if we got a signal, the user asked it be passed to
5756 We got our expected trap, but decided we should resume from
5759 We're going to run this baby now!
5761 Note that insert_breakpoints won't try to re-insert
5762 already inserted breakpoints. Therefore, we don't
5763 care if breakpoints were already inserted, or not. */
5765 if (ecs
->event_thread
->stepping_over_breakpoint
)
5767 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
5769 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
5771 /* Since we can't do a displaced step, we have to remove
5772 the breakpoint while we step it. To keep things
5773 simple, we remove them all. */
5774 remove_breakpoints ();
5779 volatile struct gdb_exception e
;
5781 /* Stop stepping if inserting breakpoints fails. */
5782 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5784 insert_breakpoints ();
5788 exception_print (gdb_stderr
, e
);
5789 stop_stepping (ecs
);
5794 ecs
->event_thread
->control
.trap_expected
5795 = ecs
->event_thread
->stepping_over_breakpoint
;
5797 /* Do not deliver GDB_SIGNAL_TRAP (except when the user
5798 explicitly specifies that such a signal should be delivered
5799 to the target program). Typically, that would occur when a
5800 user is debugging a target monitor on a simulator: the target
5801 monitor sets a breakpoint; the simulator encounters this
5802 breakpoint and halts the simulation handing control to GDB;
5803 GDB, noting that the stop address doesn't map to any known
5804 breakpoint, returns control back to the simulator; the
5805 simulator then delivers the hardware equivalent of a
5806 GDB_SIGNAL_TRAP to the program being debugged. */
5807 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5808 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5809 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5811 discard_cleanups (old_cleanups
);
5812 resume (currently_stepping (ecs
->event_thread
),
5813 ecs
->event_thread
->suspend
.stop_signal
);
5816 prepare_to_wait (ecs
);
5819 /* This function normally comes after a resume, before
5820 handle_inferior_event exits. It takes care of any last bits of
5821 housekeeping, and sets the all-important wait_some_more flag. */
5824 prepare_to_wait (struct execution_control_state
*ecs
)
5827 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
5829 /* This is the old end of the while loop. Let everybody know we
5830 want to wait for the inferior some more and get called again
5832 ecs
->wait_some_more
= 1;
5835 /* Several print_*_reason functions to print why the inferior has stopped.
5836 We always print something when the inferior exits, or receives a signal.
5837 The rest of the cases are dealt with later on in normal_stop and
5838 print_it_typical. Ideally there should be a call to one of these
5839 print_*_reason functions functions from handle_inferior_event each time
5840 stop_stepping is called. */
5842 /* Print why the inferior has stopped.
5843 We are done with a step/next/si/ni command, print why the inferior has
5844 stopped. For now print nothing. Print a message only if not in the middle
5845 of doing a "step n" operation for n > 1. */
5848 print_end_stepping_range_reason (void)
5850 if ((!inferior_thread ()->step_multi
5851 || !inferior_thread ()->control
.stop_step
)
5852 && ui_out_is_mi_like_p (current_uiout
))
5853 ui_out_field_string (current_uiout
, "reason",
5854 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
5857 /* The inferior was terminated by a signal, print why it stopped. */
5860 print_signal_exited_reason (enum gdb_signal siggnal
)
5862 struct ui_out
*uiout
= current_uiout
;
5864 annotate_signalled ();
5865 if (ui_out_is_mi_like_p (uiout
))
5867 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
5868 ui_out_text (uiout
, "\nProgram terminated with signal ");
5869 annotate_signal_name ();
5870 ui_out_field_string (uiout
, "signal-name",
5871 gdb_signal_to_name (siggnal
));
5872 annotate_signal_name_end ();
5873 ui_out_text (uiout
, ", ");
5874 annotate_signal_string ();
5875 ui_out_field_string (uiout
, "signal-meaning",
5876 gdb_signal_to_string (siggnal
));
5877 annotate_signal_string_end ();
5878 ui_out_text (uiout
, ".\n");
5879 ui_out_text (uiout
, "The program no longer exists.\n");
5882 /* The inferior program is finished, print why it stopped. */
5885 print_exited_reason (int exitstatus
)
5887 struct inferior
*inf
= current_inferior ();
5888 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
5889 struct ui_out
*uiout
= current_uiout
;
5891 annotate_exited (exitstatus
);
5894 if (ui_out_is_mi_like_p (uiout
))
5895 ui_out_field_string (uiout
, "reason",
5896 async_reason_lookup (EXEC_ASYNC_EXITED
));
5897 ui_out_text (uiout
, "[Inferior ");
5898 ui_out_text (uiout
, plongest (inf
->num
));
5899 ui_out_text (uiout
, " (");
5900 ui_out_text (uiout
, pidstr
);
5901 ui_out_text (uiout
, ") exited with code ");
5902 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
5903 ui_out_text (uiout
, "]\n");
5907 if (ui_out_is_mi_like_p (uiout
))
5909 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
5910 ui_out_text (uiout
, "[Inferior ");
5911 ui_out_text (uiout
, plongest (inf
->num
));
5912 ui_out_text (uiout
, " (");
5913 ui_out_text (uiout
, pidstr
);
5914 ui_out_text (uiout
, ") exited normally]\n");
5916 /* Support the --return-child-result option. */
5917 return_child_result_value
= exitstatus
;
5920 /* Signal received, print why the inferior has stopped. The signal table
5921 tells us to print about it. */
5924 print_signal_received_reason (enum gdb_signal siggnal
)
5926 struct ui_out
*uiout
= current_uiout
;
5930 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
5932 struct thread_info
*t
= inferior_thread ();
5934 ui_out_text (uiout
, "\n[");
5935 ui_out_field_string (uiout
, "thread-name",
5936 target_pid_to_str (t
->ptid
));
5937 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
5938 ui_out_text (uiout
, " stopped");
5942 ui_out_text (uiout
, "\nProgram received signal ");
5943 annotate_signal_name ();
5944 if (ui_out_is_mi_like_p (uiout
))
5946 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
5947 ui_out_field_string (uiout
, "signal-name",
5948 gdb_signal_to_name (siggnal
));
5949 annotate_signal_name_end ();
5950 ui_out_text (uiout
, ", ");
5951 annotate_signal_string ();
5952 ui_out_field_string (uiout
, "signal-meaning",
5953 gdb_signal_to_string (siggnal
));
5954 annotate_signal_string_end ();
5956 ui_out_text (uiout
, ".\n");
5959 /* Reverse execution: target ran out of history info, print why the inferior
5963 print_no_history_reason (void)
5965 ui_out_text (current_uiout
, "\nNo more reverse-execution history.\n");
5968 /* Here to return control to GDB when the inferior stops for real.
5969 Print appropriate messages, remove breakpoints, give terminal our modes.
5971 STOP_PRINT_FRAME nonzero means print the executing frame
5972 (pc, function, args, file, line number and line text).
5973 BREAKPOINTS_FAILED nonzero means stop was due to error
5974 attempting to insert breakpoints. */
5979 struct target_waitstatus last
;
5981 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
5983 get_last_target_status (&last_ptid
, &last
);
5985 /* If an exception is thrown from this point on, make sure to
5986 propagate GDB's knowledge of the executing state to the
5987 frontend/user running state. A QUIT is an easy exception to see
5988 here, so do this before any filtered output. */
5990 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
5991 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5992 && last
.kind
!= TARGET_WAITKIND_EXITED
5993 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5994 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
5996 /* In non-stop mode, we don't want GDB to switch threads behind the
5997 user's back, to avoid races where the user is typing a command to
5998 apply to thread x, but GDB switches to thread y before the user
5999 finishes entering the command. */
6001 /* As with the notification of thread events, we want to delay
6002 notifying the user that we've switched thread context until
6003 the inferior actually stops.
6005 There's no point in saying anything if the inferior has exited.
6006 Note that SIGNALLED here means "exited with a signal", not
6007 "received a signal". */
6009 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
6010 && target_has_execution
6011 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6012 && last
.kind
!= TARGET_WAITKIND_EXITED
6013 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6015 target_terminal_ours_for_output ();
6016 printf_filtered (_("[Switching to %s]\n"),
6017 target_pid_to_str (inferior_ptid
));
6018 annotate_thread_changed ();
6019 previous_inferior_ptid
= inferior_ptid
;
6022 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
6024 gdb_assert (sync_execution
|| !target_can_async_p ());
6026 target_terminal_ours_for_output ();
6027 printf_filtered (_("No unwaited-for children left.\n"));
6030 if (!breakpoints_always_inserted_mode () && target_has_execution
)
6032 if (remove_breakpoints ())
6034 target_terminal_ours_for_output ();
6035 printf_filtered (_("Cannot remove breakpoints because "
6036 "program is no longer writable.\nFurther "
6037 "execution is probably impossible.\n"));
6041 /* If an auto-display called a function and that got a signal,
6042 delete that auto-display to avoid an infinite recursion. */
6044 if (stopped_by_random_signal
)
6045 disable_current_display ();
6047 /* Don't print a message if in the middle of doing a "step n"
6048 operation for n > 1 */
6049 if (target_has_execution
6050 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6051 && last
.kind
!= TARGET_WAITKIND_EXITED
6052 && inferior_thread ()->step_multi
6053 && inferior_thread ()->control
.stop_step
)
6056 target_terminal_ours ();
6057 async_enable_stdin ();
6059 /* Set the current source location. This will also happen if we
6060 display the frame below, but the current SAL will be incorrect
6061 during a user hook-stop function. */
6062 if (has_stack_frames () && !stop_stack_dummy
)
6063 set_current_sal_from_frame (get_current_frame (), 1);
6065 /* Let the user/frontend see the threads as stopped. */
6066 do_cleanups (old_chain
);
6068 /* Look up the hook_stop and run it (CLI internally handles problem
6069 of stop_command's pre-hook not existing). */
6071 catch_errors (hook_stop_stub
, stop_command
,
6072 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
6074 if (!has_stack_frames ())
6077 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
6078 || last
.kind
== TARGET_WAITKIND_EXITED
)
6081 /* Select innermost stack frame - i.e., current frame is frame 0,
6082 and current location is based on that.
6083 Don't do this on return from a stack dummy routine,
6084 or if the program has exited. */
6086 if (!stop_stack_dummy
)
6088 select_frame (get_current_frame ());
6090 /* Print current location without a level number, if
6091 we have changed functions or hit a breakpoint.
6092 Print source line if we have one.
6093 bpstat_print() contains the logic deciding in detail
6094 what to print, based on the event(s) that just occurred. */
6096 /* If --batch-silent is enabled then there's no need to print the current
6097 source location, and to try risks causing an error message about
6098 missing source files. */
6099 if (stop_print_frame
&& !batch_silent
)
6103 int do_frame_printing
= 1;
6104 struct thread_info
*tp
= inferior_thread ();
6106 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, last
.kind
);
6110 /* FIXME: cagney/2002-12-01: Given that a frame ID does
6111 (or should) carry around the function and does (or
6112 should) use that when doing a frame comparison. */
6113 if (tp
->control
.stop_step
6114 && frame_id_eq (tp
->control
.step_frame_id
,
6115 get_frame_id (get_current_frame ()))
6116 && step_start_function
== find_pc_function (stop_pc
))
6117 source_flag
= SRC_LINE
; /* Finished step, just
6118 print source line. */
6120 source_flag
= SRC_AND_LOC
; /* Print location and
6123 case PRINT_SRC_AND_LOC
:
6124 source_flag
= SRC_AND_LOC
; /* Print location and
6127 case PRINT_SRC_ONLY
:
6128 source_flag
= SRC_LINE
;
6131 source_flag
= SRC_LINE
; /* something bogus */
6132 do_frame_printing
= 0;
6135 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6138 /* The behavior of this routine with respect to the source
6140 SRC_LINE: Print only source line
6141 LOCATION: Print only location
6142 SRC_AND_LOC: Print location and source line. */
6143 if (do_frame_printing
)
6144 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
6146 /* Display the auto-display expressions. */
6151 /* Save the function value return registers, if we care.
6152 We might be about to restore their previous contents. */
6153 if (inferior_thread ()->control
.proceed_to_finish
6154 && execution_direction
!= EXEC_REVERSE
)
6156 /* This should not be necessary. */
6158 regcache_xfree (stop_registers
);
6160 /* NB: The copy goes through to the target picking up the value of
6161 all the registers. */
6162 stop_registers
= regcache_dup (get_current_regcache ());
6165 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6167 /* Pop the empty frame that contains the stack dummy.
6168 This also restores inferior state prior to the call
6169 (struct infcall_suspend_state). */
6170 struct frame_info
*frame
= get_current_frame ();
6172 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6174 /* frame_pop() calls reinit_frame_cache as the last thing it
6175 does which means there's currently no selected frame. We
6176 don't need to re-establish a selected frame if the dummy call
6177 returns normally, that will be done by
6178 restore_infcall_control_state. However, we do have to handle
6179 the case where the dummy call is returning after being
6180 stopped (e.g. the dummy call previously hit a breakpoint).
6181 We can't know which case we have so just always re-establish
6182 a selected frame here. */
6183 select_frame (get_current_frame ());
6187 annotate_stopped ();
6189 /* Suppress the stop observer if we're in the middle of:
6191 - a step n (n > 1), as there still more steps to be done.
6193 - a "finish" command, as the observer will be called in
6194 finish_command_continuation, so it can include the inferior
6195 function's return value.
6197 - calling an inferior function, as we pretend we inferior didn't
6198 run at all. The return value of the call is handled by the
6199 expression evaluator, through call_function_by_hand. */
6201 if (!target_has_execution
6202 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6203 || last
.kind
== TARGET_WAITKIND_EXITED
6204 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6205 || (!(inferior_thread ()->step_multi
6206 && inferior_thread ()->control
.stop_step
)
6207 && !(inferior_thread ()->control
.stop_bpstat
6208 && inferior_thread ()->control
.proceed_to_finish
)
6209 && !inferior_thread ()->control
.in_infcall
))
6211 if (!ptid_equal (inferior_ptid
, null_ptid
))
6212 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6215 observer_notify_normal_stop (NULL
, stop_print_frame
);
6218 if (target_has_execution
)
6220 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6221 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6222 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6223 Delete any breakpoint that is to be deleted at the next stop. */
6224 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6227 /* Try to get rid of automatically added inferiors that are no
6228 longer needed. Keeping those around slows down things linearly.
6229 Note that this never removes the current inferior. */
6234 hook_stop_stub (void *cmd
)
6236 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6241 signal_stop_state (int signo
)
6243 return signal_stop
[signo
];
6247 signal_print_state (int signo
)
6249 return signal_print
[signo
];
6253 signal_pass_state (int signo
)
6255 return signal_program
[signo
];
6259 signal_cache_update (int signo
)
6263 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6264 signal_cache_update (signo
);
6269 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6270 && signal_print
[signo
] == 0
6271 && signal_program
[signo
] == 1
6272 && signal_catch
[signo
] == 0);
6276 signal_stop_update (int signo
, int state
)
6278 int ret
= signal_stop
[signo
];
6280 signal_stop
[signo
] = state
;
6281 signal_cache_update (signo
);
6286 signal_print_update (int signo
, int state
)
6288 int ret
= signal_print
[signo
];
6290 signal_print
[signo
] = state
;
6291 signal_cache_update (signo
);
6296 signal_pass_update (int signo
, int state
)
6298 int ret
= signal_program
[signo
];
6300 signal_program
[signo
] = state
;
6301 signal_cache_update (signo
);
6305 /* Update the global 'signal_catch' from INFO and notify the
6309 signal_catch_update (const unsigned int *info
)
6313 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
6314 signal_catch
[i
] = info
[i
] > 0;
6315 signal_cache_update (-1);
6316 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6320 sig_print_header (void)
6322 printf_filtered (_("Signal Stop\tPrint\tPass "
6323 "to program\tDescription\n"));
6327 sig_print_info (enum gdb_signal oursig
)
6329 const char *name
= gdb_signal_to_name (oursig
);
6330 int name_padding
= 13 - strlen (name
);
6332 if (name_padding
<= 0)
6335 printf_filtered ("%s", name
);
6336 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6337 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6338 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6339 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6340 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6343 /* Specify how various signals in the inferior should be handled. */
6346 handle_command (char *args
, int from_tty
)
6349 int digits
, wordlen
;
6350 int sigfirst
, signum
, siglast
;
6351 enum gdb_signal oursig
;
6354 unsigned char *sigs
;
6355 struct cleanup
*old_chain
;
6359 error_no_arg (_("signal to handle"));
6362 /* Allocate and zero an array of flags for which signals to handle. */
6364 nsigs
= (int) GDB_SIGNAL_LAST
;
6365 sigs
= (unsigned char *) alloca (nsigs
);
6366 memset (sigs
, 0, nsigs
);
6368 /* Break the command line up into args. */
6370 argv
= gdb_buildargv (args
);
6371 old_chain
= make_cleanup_freeargv (argv
);
6373 /* Walk through the args, looking for signal oursigs, signal names, and
6374 actions. Signal numbers and signal names may be interspersed with
6375 actions, with the actions being performed for all signals cumulatively
6376 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6378 while (*argv
!= NULL
)
6380 wordlen
= strlen (*argv
);
6381 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6385 sigfirst
= siglast
= -1;
6387 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6389 /* Apply action to all signals except those used by the
6390 debugger. Silently skip those. */
6393 siglast
= nsigs
- 1;
6395 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6397 SET_SIGS (nsigs
, sigs
, signal_stop
);
6398 SET_SIGS (nsigs
, sigs
, signal_print
);
6400 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6402 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6404 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6406 SET_SIGS (nsigs
, sigs
, signal_print
);
6408 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6410 SET_SIGS (nsigs
, sigs
, signal_program
);
6412 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6414 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6416 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6418 SET_SIGS (nsigs
, sigs
, signal_program
);
6420 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6422 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6423 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6425 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6427 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6429 else if (digits
> 0)
6431 /* It is numeric. The numeric signal refers to our own
6432 internal signal numbering from target.h, not to host/target
6433 signal number. This is a feature; users really should be
6434 using symbolic names anyway, and the common ones like
6435 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6437 sigfirst
= siglast
= (int)
6438 gdb_signal_from_command (atoi (*argv
));
6439 if ((*argv
)[digits
] == '-')
6442 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6444 if (sigfirst
> siglast
)
6446 /* Bet he didn't figure we'd think of this case... */
6454 oursig
= gdb_signal_from_name (*argv
);
6455 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6457 sigfirst
= siglast
= (int) oursig
;
6461 /* Not a number and not a recognized flag word => complain. */
6462 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6466 /* If any signal numbers or symbol names were found, set flags for
6467 which signals to apply actions to. */
6469 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6471 switch ((enum gdb_signal
) signum
)
6473 case GDB_SIGNAL_TRAP
:
6474 case GDB_SIGNAL_INT
:
6475 if (!allsigs
&& !sigs
[signum
])
6477 if (query (_("%s is used by the debugger.\n\
6478 Are you sure you want to change it? "),
6479 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6485 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6486 gdb_flush (gdb_stdout
);
6491 case GDB_SIGNAL_DEFAULT
:
6492 case GDB_SIGNAL_UNKNOWN
:
6493 /* Make sure that "all" doesn't print these. */
6504 for (signum
= 0; signum
< nsigs
; signum
++)
6507 signal_cache_update (-1);
6508 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6509 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
6513 /* Show the results. */
6514 sig_print_header ();
6515 for (; signum
< nsigs
; signum
++)
6517 sig_print_info (signum
);
6523 do_cleanups (old_chain
);
6526 /* Complete the "handle" command. */
6528 static VEC (char_ptr
) *
6529 handle_completer (struct cmd_list_element
*ignore
,
6530 const char *text
, const char *word
)
6532 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
6533 static const char * const keywords
[] =
6547 vec_signals
= signal_completer (ignore
, text
, word
);
6548 vec_keywords
= complete_on_enum (keywords
, word
, word
);
6550 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
6551 VEC_free (char_ptr
, vec_signals
);
6552 VEC_free (char_ptr
, vec_keywords
);
6557 xdb_handle_command (char *args
, int from_tty
)
6560 struct cleanup
*old_chain
;
6563 error_no_arg (_("xdb command"));
6565 /* Break the command line up into args. */
6567 argv
= gdb_buildargv (args
);
6568 old_chain
= make_cleanup_freeargv (argv
);
6569 if (argv
[1] != (char *) NULL
)
6574 bufLen
= strlen (argv
[0]) + 20;
6575 argBuf
= (char *) xmalloc (bufLen
);
6579 enum gdb_signal oursig
;
6581 oursig
= gdb_signal_from_name (argv
[0]);
6582 memset (argBuf
, 0, bufLen
);
6583 if (strcmp (argv
[1], "Q") == 0)
6584 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6587 if (strcmp (argv
[1], "s") == 0)
6589 if (!signal_stop
[oursig
])
6590 sprintf (argBuf
, "%s %s", argv
[0], "stop");
6592 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
6594 else if (strcmp (argv
[1], "i") == 0)
6596 if (!signal_program
[oursig
])
6597 sprintf (argBuf
, "%s %s", argv
[0], "pass");
6599 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
6601 else if (strcmp (argv
[1], "r") == 0)
6603 if (!signal_print
[oursig
])
6604 sprintf (argBuf
, "%s %s", argv
[0], "print");
6606 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6612 handle_command (argBuf
, from_tty
);
6614 printf_filtered (_("Invalid signal handling flag.\n"));
6619 do_cleanups (old_chain
);
6623 gdb_signal_from_command (int num
)
6625 if (num
>= 1 && num
<= 15)
6626 return (enum gdb_signal
) num
;
6627 error (_("Only signals 1-15 are valid as numeric signals.\n\
6628 Use \"info signals\" for a list of symbolic signals."));
6631 /* Print current contents of the tables set by the handle command.
6632 It is possible we should just be printing signals actually used
6633 by the current target (but for things to work right when switching
6634 targets, all signals should be in the signal tables). */
6637 signals_info (char *signum_exp
, int from_tty
)
6639 enum gdb_signal oursig
;
6641 sig_print_header ();
6645 /* First see if this is a symbol name. */
6646 oursig
= gdb_signal_from_name (signum_exp
);
6647 if (oursig
== GDB_SIGNAL_UNKNOWN
)
6649 /* No, try numeric. */
6651 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
6653 sig_print_info (oursig
);
6657 printf_filtered ("\n");
6658 /* These ugly casts brought to you by the native VAX compiler. */
6659 for (oursig
= GDB_SIGNAL_FIRST
;
6660 (int) oursig
< (int) GDB_SIGNAL_LAST
;
6661 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
6665 if (oursig
!= GDB_SIGNAL_UNKNOWN
6666 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
6667 sig_print_info (oursig
);
6670 printf_filtered (_("\nUse the \"handle\" command "
6671 "to change these tables.\n"));
6674 /* Check if it makes sense to read $_siginfo from the current thread
6675 at this point. If not, throw an error. */
6678 validate_siginfo_access (void)
6680 /* No current inferior, no siginfo. */
6681 if (ptid_equal (inferior_ptid
, null_ptid
))
6682 error (_("No thread selected."));
6684 /* Don't try to read from a dead thread. */
6685 if (is_exited (inferior_ptid
))
6686 error (_("The current thread has terminated"));
6688 /* ... or from a spinning thread. */
6689 if (is_running (inferior_ptid
))
6690 error (_("Selected thread is running."));
6693 /* The $_siginfo convenience variable is a bit special. We don't know
6694 for sure the type of the value until we actually have a chance to
6695 fetch the data. The type can change depending on gdbarch, so it is
6696 also dependent on which thread you have selected.
6698 1. making $_siginfo be an internalvar that creates a new value on
6701 2. making the value of $_siginfo be an lval_computed value. */
6703 /* This function implements the lval_computed support for reading a
6707 siginfo_value_read (struct value
*v
)
6709 LONGEST transferred
;
6711 validate_siginfo_access ();
6714 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
6716 value_contents_all_raw (v
),
6718 TYPE_LENGTH (value_type (v
)));
6720 if (transferred
!= TYPE_LENGTH (value_type (v
)))
6721 error (_("Unable to read siginfo"));
6724 /* This function implements the lval_computed support for writing a
6728 siginfo_value_write (struct value
*v
, struct value
*fromval
)
6730 LONGEST transferred
;
6732 validate_siginfo_access ();
6734 transferred
= target_write (¤t_target
,
6735 TARGET_OBJECT_SIGNAL_INFO
,
6737 value_contents_all_raw (fromval
),
6739 TYPE_LENGTH (value_type (fromval
)));
6741 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
6742 error (_("Unable to write siginfo"));
6745 static const struct lval_funcs siginfo_value_funcs
=
6751 /* Return a new value with the correct type for the siginfo object of
6752 the current thread using architecture GDBARCH. Return a void value
6753 if there's no object available. */
6755 static struct value
*
6756 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
6759 if (target_has_stack
6760 && !ptid_equal (inferior_ptid
, null_ptid
)
6761 && gdbarch_get_siginfo_type_p (gdbarch
))
6763 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6765 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
6768 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
6772 /* infcall_suspend_state contains state about the program itself like its
6773 registers and any signal it received when it last stopped.
6774 This state must be restored regardless of how the inferior function call
6775 ends (either successfully, or after it hits a breakpoint or signal)
6776 if the program is to properly continue where it left off. */
6778 struct infcall_suspend_state
6780 struct thread_suspend_state thread_suspend
;
6781 #if 0 /* Currently unused and empty structures are not valid C. */
6782 struct inferior_suspend_state inferior_suspend
;
6787 struct regcache
*registers
;
6789 /* Format of SIGINFO_DATA or NULL if it is not present. */
6790 struct gdbarch
*siginfo_gdbarch
;
6792 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6793 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6794 content would be invalid. */
6795 gdb_byte
*siginfo_data
;
6798 struct infcall_suspend_state
*
6799 save_infcall_suspend_state (void)
6801 struct infcall_suspend_state
*inf_state
;
6802 struct thread_info
*tp
= inferior_thread ();
6804 struct inferior
*inf
= current_inferior ();
6806 struct regcache
*regcache
= get_current_regcache ();
6807 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6808 gdb_byte
*siginfo_data
= NULL
;
6810 if (gdbarch_get_siginfo_type_p (gdbarch
))
6812 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6813 size_t len
= TYPE_LENGTH (type
);
6814 struct cleanup
*back_to
;
6816 siginfo_data
= xmalloc (len
);
6817 back_to
= make_cleanup (xfree
, siginfo_data
);
6819 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6820 siginfo_data
, 0, len
) == len
)
6821 discard_cleanups (back_to
);
6824 /* Errors ignored. */
6825 do_cleanups (back_to
);
6826 siginfo_data
= NULL
;
6830 inf_state
= XZALLOC (struct infcall_suspend_state
);
6834 inf_state
->siginfo_gdbarch
= gdbarch
;
6835 inf_state
->siginfo_data
= siginfo_data
;
6838 inf_state
->thread_suspend
= tp
->suspend
;
6839 #if 0 /* Currently unused and empty structures are not valid C. */
6840 inf_state
->inferior_suspend
= inf
->suspend
;
6843 /* run_inferior_call will not use the signal due to its `proceed' call with
6844 GDB_SIGNAL_0 anyway. */
6845 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6847 inf_state
->stop_pc
= stop_pc
;
6849 inf_state
->registers
= regcache_dup (regcache
);
6854 /* Restore inferior session state to INF_STATE. */
6857 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6859 struct thread_info
*tp
= inferior_thread ();
6861 struct inferior
*inf
= current_inferior ();
6863 struct regcache
*regcache
= get_current_regcache ();
6864 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6866 tp
->suspend
= inf_state
->thread_suspend
;
6867 #if 0 /* Currently unused and empty structures are not valid C. */
6868 inf
->suspend
= inf_state
->inferior_suspend
;
6871 stop_pc
= inf_state
->stop_pc
;
6873 if (inf_state
->siginfo_gdbarch
== gdbarch
)
6875 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6877 /* Errors ignored. */
6878 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6879 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
6882 /* The inferior can be gone if the user types "print exit(0)"
6883 (and perhaps other times). */
6884 if (target_has_execution
)
6885 /* NB: The register write goes through to the target. */
6886 regcache_cpy (regcache
, inf_state
->registers
);
6888 discard_infcall_suspend_state (inf_state
);
6892 do_restore_infcall_suspend_state_cleanup (void *state
)
6894 restore_infcall_suspend_state (state
);
6898 make_cleanup_restore_infcall_suspend_state
6899 (struct infcall_suspend_state
*inf_state
)
6901 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
6905 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6907 regcache_xfree (inf_state
->registers
);
6908 xfree (inf_state
->siginfo_data
);
6913 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
6915 return inf_state
->registers
;
6918 /* infcall_control_state contains state regarding gdb's control of the
6919 inferior itself like stepping control. It also contains session state like
6920 the user's currently selected frame. */
6922 struct infcall_control_state
6924 struct thread_control_state thread_control
;
6925 struct inferior_control_state inferior_control
;
6928 enum stop_stack_kind stop_stack_dummy
;
6929 int stopped_by_random_signal
;
6930 int stop_after_trap
;
6932 /* ID if the selected frame when the inferior function call was made. */
6933 struct frame_id selected_frame_id
;
6936 /* Save all of the information associated with the inferior<==>gdb
6939 struct infcall_control_state
*
6940 save_infcall_control_state (void)
6942 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
6943 struct thread_info
*tp
= inferior_thread ();
6944 struct inferior
*inf
= current_inferior ();
6946 inf_status
->thread_control
= tp
->control
;
6947 inf_status
->inferior_control
= inf
->control
;
6949 tp
->control
.step_resume_breakpoint
= NULL
;
6950 tp
->control
.exception_resume_breakpoint
= NULL
;
6952 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6953 chain. If caller's caller is walking the chain, they'll be happier if we
6954 hand them back the original chain when restore_infcall_control_state is
6956 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
6959 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
6960 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
6961 inf_status
->stop_after_trap
= stop_after_trap
;
6963 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
6969 restore_selected_frame (void *args
)
6971 struct frame_id
*fid
= (struct frame_id
*) args
;
6972 struct frame_info
*frame
;
6974 frame
= frame_find_by_id (*fid
);
6976 /* If inf_status->selected_frame_id is NULL, there was no previously
6980 warning (_("Unable to restore previously selected frame."));
6984 select_frame (frame
);
6989 /* Restore inferior session state to INF_STATUS. */
6992 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
6994 struct thread_info
*tp
= inferior_thread ();
6995 struct inferior
*inf
= current_inferior ();
6997 if (tp
->control
.step_resume_breakpoint
)
6998 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
7000 if (tp
->control
.exception_resume_breakpoint
)
7001 tp
->control
.exception_resume_breakpoint
->disposition
7002 = disp_del_at_next_stop
;
7004 /* Handle the bpstat_copy of the chain. */
7005 bpstat_clear (&tp
->control
.stop_bpstat
);
7007 tp
->control
= inf_status
->thread_control
;
7008 inf
->control
= inf_status
->inferior_control
;
7011 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
7012 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
7013 stop_after_trap
= inf_status
->stop_after_trap
;
7015 if (target_has_stack
)
7017 /* The point of catch_errors is that if the stack is clobbered,
7018 walking the stack might encounter a garbage pointer and
7019 error() trying to dereference it. */
7021 (restore_selected_frame
, &inf_status
->selected_frame_id
,
7022 "Unable to restore previously selected frame:\n",
7023 RETURN_MASK_ERROR
) == 0)
7024 /* Error in restoring the selected frame. Select the innermost
7026 select_frame (get_current_frame ());
7033 do_restore_infcall_control_state_cleanup (void *sts
)
7035 restore_infcall_control_state (sts
);
7039 make_cleanup_restore_infcall_control_state
7040 (struct infcall_control_state
*inf_status
)
7042 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
7046 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
7048 if (inf_status
->thread_control
.step_resume_breakpoint
)
7049 inf_status
->thread_control
.step_resume_breakpoint
->disposition
7050 = disp_del_at_next_stop
;
7052 if (inf_status
->thread_control
.exception_resume_breakpoint
)
7053 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
7054 = disp_del_at_next_stop
;
7056 /* See save_infcall_control_state for info on stop_bpstat. */
7057 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
7063 ptid_match (ptid_t ptid
, ptid_t filter
)
7065 if (ptid_equal (filter
, minus_one_ptid
))
7067 if (ptid_is_pid (filter
)
7068 && ptid_get_pid (ptid
) == ptid_get_pid (filter
))
7070 else if (ptid_equal (ptid
, filter
))
7076 /* restore_inferior_ptid() will be used by the cleanup machinery
7077 to restore the inferior_ptid value saved in a call to
7078 save_inferior_ptid(). */
7081 restore_inferior_ptid (void *arg
)
7083 ptid_t
*saved_ptid_ptr
= arg
;
7085 inferior_ptid
= *saved_ptid_ptr
;
7089 /* Save the value of inferior_ptid so that it may be restored by a
7090 later call to do_cleanups(). Returns the struct cleanup pointer
7091 needed for later doing the cleanup. */
7094 save_inferior_ptid (void)
7096 ptid_t
*saved_ptid_ptr
;
7098 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
7099 *saved_ptid_ptr
= inferior_ptid
;
7100 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
7103 /* See inferior.h. */
7106 clear_exit_convenience_vars (void)
7108 clear_internalvar (lookup_internalvar ("_exitsignal"));
7109 clear_internalvar (lookup_internalvar ("_exitcode"));
7113 /* User interface for reverse debugging:
7114 Set exec-direction / show exec-direction commands
7115 (returns error unless target implements to_set_exec_direction method). */
7117 int execution_direction
= EXEC_FORWARD
;
7118 static const char exec_forward
[] = "forward";
7119 static const char exec_reverse
[] = "reverse";
7120 static const char *exec_direction
= exec_forward
;
7121 static const char *const exec_direction_names
[] = {
7128 set_exec_direction_func (char *args
, int from_tty
,
7129 struct cmd_list_element
*cmd
)
7131 if (target_can_execute_reverse
)
7133 if (!strcmp (exec_direction
, exec_forward
))
7134 execution_direction
= EXEC_FORWARD
;
7135 else if (!strcmp (exec_direction
, exec_reverse
))
7136 execution_direction
= EXEC_REVERSE
;
7140 exec_direction
= exec_forward
;
7141 error (_("Target does not support this operation."));
7146 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7147 struct cmd_list_element
*cmd
, const char *value
)
7149 switch (execution_direction
) {
7151 fprintf_filtered (out
, _("Forward.\n"));
7154 fprintf_filtered (out
, _("Reverse.\n"));
7157 internal_error (__FILE__
, __LINE__
,
7158 _("bogus execution_direction value: %d"),
7159 (int) execution_direction
);
7164 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7165 struct cmd_list_element
*c
, const char *value
)
7167 fprintf_filtered (file
, _("Resuming the execution of threads "
7168 "of all processes is %s.\n"), value
);
7171 /* Implementation of `siginfo' variable. */
7173 static const struct internalvar_funcs siginfo_funcs
=
7181 _initialize_infrun (void)
7185 struct cmd_list_element
*c
;
7187 add_info ("signals", signals_info
, _("\
7188 What debugger does when program gets various signals.\n\
7189 Specify a signal as argument to print info on that signal only."));
7190 add_info_alias ("handle", "signals", 0);
7192 c
= add_com ("handle", class_run
, handle_command
, _("\
7193 Specify how to handle signals.\n\
7194 Usage: handle SIGNAL [ACTIONS]\n\
7195 Args are signals and actions to apply to those signals.\n\
7196 If no actions are specified, the current settings for the specified signals\n\
7197 will be displayed instead.\n\
7199 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7200 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7201 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7202 The special arg \"all\" is recognized to mean all signals except those\n\
7203 used by the debugger, typically SIGTRAP and SIGINT.\n\
7205 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7206 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7207 Stop means reenter debugger if this signal happens (implies print).\n\
7208 Print means print a message if this signal happens.\n\
7209 Pass means let program see this signal; otherwise program doesn't know.\n\
7210 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7211 Pass and Stop may be combined.\n\
7213 Multiple signals may be specified. Signal numbers and signal names\n\
7214 may be interspersed with actions, with the actions being performed for\n\
7215 all signals cumulatively specified."));
7216 set_cmd_completer (c
, handle_completer
);
7220 add_com ("lz", class_info
, signals_info
, _("\
7221 What debugger does when program gets various signals.\n\
7222 Specify a signal as argument to print info on that signal only."));
7223 add_com ("z", class_run
, xdb_handle_command
, _("\
7224 Specify how to handle a signal.\n\
7225 Args are signals and actions to apply to those signals.\n\
7226 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7227 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7228 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7229 The special arg \"all\" is recognized to mean all signals except those\n\
7230 used by the debugger, typically SIGTRAP and SIGINT.\n\
7231 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7232 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7233 nopass), \"Q\" (noprint)\n\
7234 Stop means reenter debugger if this signal happens (implies print).\n\
7235 Print means print a message if this signal happens.\n\
7236 Pass means let program see this signal; otherwise program doesn't know.\n\
7237 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7238 Pass and Stop may be combined."));
7242 stop_command
= add_cmd ("stop", class_obscure
,
7243 not_just_help_class_command
, _("\
7244 There is no `stop' command, but you can set a hook on `stop'.\n\
7245 This allows you to set a list of commands to be run each time execution\n\
7246 of the program stops."), &cmdlist
);
7248 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7249 Set inferior debugging."), _("\
7250 Show inferior debugging."), _("\
7251 When non-zero, inferior specific debugging is enabled."),
7254 &setdebuglist
, &showdebuglist
);
7256 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7257 &debug_displaced
, _("\
7258 Set displaced stepping debugging."), _("\
7259 Show displaced stepping debugging."), _("\
7260 When non-zero, displaced stepping specific debugging is enabled."),
7262 show_debug_displaced
,
7263 &setdebuglist
, &showdebuglist
);
7265 add_setshow_boolean_cmd ("non-stop", no_class
,
7267 Set whether gdb controls the inferior in non-stop mode."), _("\
7268 Show whether gdb controls the inferior in non-stop mode."), _("\
7269 When debugging a multi-threaded program and this setting is\n\
7270 off (the default, also called all-stop mode), when one thread stops\n\
7271 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7272 all other threads in the program while you interact with the thread of\n\
7273 interest. When you continue or step a thread, you can allow the other\n\
7274 threads to run, or have them remain stopped, but while you inspect any\n\
7275 thread's state, all threads stop.\n\
7277 In non-stop mode, when one thread stops, other threads can continue\n\
7278 to run freely. You'll be able to step each thread independently,\n\
7279 leave it stopped or free to run as needed."),
7285 numsigs
= (int) GDB_SIGNAL_LAST
;
7286 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7287 signal_print
= (unsigned char *)
7288 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7289 signal_program
= (unsigned char *)
7290 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7291 signal_catch
= (unsigned char *)
7292 xmalloc (sizeof (signal_catch
[0]) * numsigs
);
7293 signal_pass
= (unsigned char *)
7294 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7295 for (i
= 0; i
< numsigs
; i
++)
7298 signal_print
[i
] = 1;
7299 signal_program
[i
] = 1;
7300 signal_catch
[i
] = 0;
7303 /* Signals caused by debugger's own actions
7304 should not be given to the program afterwards. */
7305 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7306 signal_program
[GDB_SIGNAL_INT
] = 0;
7308 /* Signals that are not errors should not normally enter the debugger. */
7309 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7310 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7311 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7312 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7313 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7314 signal_print
[GDB_SIGNAL_PROF
] = 0;
7315 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7316 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7317 signal_stop
[GDB_SIGNAL_IO
] = 0;
7318 signal_print
[GDB_SIGNAL_IO
] = 0;
7319 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7320 signal_print
[GDB_SIGNAL_POLL
] = 0;
7321 signal_stop
[GDB_SIGNAL_URG
] = 0;
7322 signal_print
[GDB_SIGNAL_URG
] = 0;
7323 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7324 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7325 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7326 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7328 /* These signals are used internally by user-level thread
7329 implementations. (See signal(5) on Solaris.) Like the above
7330 signals, a healthy program receives and handles them as part of
7331 its normal operation. */
7332 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7333 signal_print
[GDB_SIGNAL_LWP
] = 0;
7334 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7335 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7336 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7337 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7339 /* Update cached state. */
7340 signal_cache_update (-1);
7342 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7343 &stop_on_solib_events
, _("\
7344 Set stopping for shared library events."), _("\
7345 Show stopping for shared library events."), _("\
7346 If nonzero, gdb will give control to the user when the dynamic linker\n\
7347 notifies gdb of shared library events. The most common event of interest\n\
7348 to the user would be loading/unloading of a new library."),
7349 set_stop_on_solib_events
,
7350 show_stop_on_solib_events
,
7351 &setlist
, &showlist
);
7353 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7354 follow_fork_mode_kind_names
,
7355 &follow_fork_mode_string
, _("\
7356 Set debugger response to a program call of fork or vfork."), _("\
7357 Show debugger response to a program call of fork or vfork."), _("\
7358 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7359 parent - the original process is debugged after a fork\n\
7360 child - the new process is debugged after a fork\n\
7361 The unfollowed process will continue to run.\n\
7362 By default, the debugger will follow the parent process."),
7364 show_follow_fork_mode_string
,
7365 &setlist
, &showlist
);
7367 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7368 follow_exec_mode_names
,
7369 &follow_exec_mode_string
, _("\
7370 Set debugger response to a program call of exec."), _("\
7371 Show debugger response to a program call of exec."), _("\
7372 An exec call replaces the program image of a process.\n\
7374 follow-exec-mode can be:\n\
7376 new - the debugger creates a new inferior and rebinds the process\n\
7377 to this new inferior. The program the process was running before\n\
7378 the exec call can be restarted afterwards by restarting the original\n\
7381 same - the debugger keeps the process bound to the same inferior.\n\
7382 The new executable image replaces the previous executable loaded in\n\
7383 the inferior. Restarting the inferior after the exec call restarts\n\
7384 the executable the process was running after the exec call.\n\
7386 By default, the debugger will use the same inferior."),
7388 show_follow_exec_mode_string
,
7389 &setlist
, &showlist
);
7391 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7392 scheduler_enums
, &scheduler_mode
, _("\
7393 Set mode for locking scheduler during execution."), _("\
7394 Show mode for locking scheduler during execution."), _("\
7395 off == no locking (threads may preempt at any time)\n\
7396 on == full locking (no thread except the current thread may run)\n\
7397 step == scheduler locked during every single-step operation.\n\
7398 In this mode, no other thread may run during a step command.\n\
7399 Other threads may run while stepping over a function call ('next')."),
7400 set_schedlock_func
, /* traps on target vector */
7401 show_scheduler_mode
,
7402 &setlist
, &showlist
);
7404 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7405 Set mode for resuming threads of all processes."), _("\
7406 Show mode for resuming threads of all processes."), _("\
7407 When on, execution commands (such as 'continue' or 'next') resume all\n\
7408 threads of all processes. When off (which is the default), execution\n\
7409 commands only resume the threads of the current process. The set of\n\
7410 threads that are resumed is further refined by the scheduler-locking\n\
7411 mode (see help set scheduler-locking)."),
7413 show_schedule_multiple
,
7414 &setlist
, &showlist
);
7416 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7417 Set mode of the step operation."), _("\
7418 Show mode of the step operation."), _("\
7419 When set, doing a step over a function without debug line information\n\
7420 will stop at the first instruction of that function. Otherwise, the\n\
7421 function is skipped and the step command stops at a different source line."),
7423 show_step_stop_if_no_debug
,
7424 &setlist
, &showlist
);
7426 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
7427 &can_use_displaced_stepping
, _("\
7428 Set debugger's willingness to use displaced stepping."), _("\
7429 Show debugger's willingness to use displaced stepping."), _("\
7430 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7431 supported by the target architecture. If off, gdb will not use displaced\n\
7432 stepping to step over breakpoints, even if such is supported by the target\n\
7433 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7434 if the target architecture supports it and non-stop mode is active, but will not\n\
7435 use it in all-stop mode (see help set non-stop)."),
7437 show_can_use_displaced_stepping
,
7438 &setlist
, &showlist
);
7440 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7441 &exec_direction
, _("Set direction of execution.\n\
7442 Options are 'forward' or 'reverse'."),
7443 _("Show direction of execution (forward/reverse)."),
7444 _("Tells gdb whether to execute forward or backward."),
7445 set_exec_direction_func
, show_exec_direction_func
,
7446 &setlist
, &showlist
);
7448 /* Set/show detach-on-fork: user-settable mode. */
7450 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7451 Set whether gdb will detach the child of a fork."), _("\
7452 Show whether gdb will detach the child of a fork."), _("\
7453 Tells gdb whether to detach the child of a fork."),
7454 NULL
, NULL
, &setlist
, &showlist
);
7456 /* Set/show disable address space randomization mode. */
7458 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7459 &disable_randomization
, _("\
7460 Set disabling of debuggee's virtual address space randomization."), _("\
7461 Show disabling of debuggee's virtual address space randomization."), _("\
7462 When this mode is on (which is the default), randomization of the virtual\n\
7463 address space is disabled. Standalone programs run with the randomization\n\
7464 enabled by default on some platforms."),
7465 &set_disable_randomization
,
7466 &show_disable_randomization
,
7467 &setlist
, &showlist
);
7469 /* ptid initializations */
7470 inferior_ptid
= null_ptid
;
7471 target_last_wait_ptid
= minus_one_ptid
;
7473 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7474 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7475 observer_attach_thread_exit (infrun_thread_thread_exit
);
7476 observer_attach_inferior_exit (infrun_inferior_exit
);
7478 /* Explicitly create without lookup, since that tries to create a
7479 value with a void typed value, and when we get here, gdbarch
7480 isn't initialized yet. At this point, we're quite sure there
7481 isn't another convenience variable of the same name. */
7482 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7484 add_setshow_boolean_cmd ("observer", no_class
,
7485 &observer_mode_1
, _("\
7486 Set whether gdb controls the inferior in observer mode."), _("\
7487 Show whether gdb controls the inferior in observer mode."), _("\
7488 In observer mode, GDB can get data from the inferior, but not\n\
7489 affect its execution. Registers and memory may not be changed,\n\
7490 breakpoints may not be set, and the program cannot be interrupted\n\