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/>. */
22 #include "gdb_string.h"
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
;
2423 int stop_func_filled_in
;
2424 CORE_ADDR stop_func_start
;
2425 CORE_ADDR stop_func_end
;
2426 const char *stop_func_name
;
2430 static void handle_inferior_event (struct execution_control_state
*ecs
);
2432 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2433 struct execution_control_state
*ecs
);
2434 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2435 struct execution_control_state
*ecs
);
2436 static void check_exception_resume (struct execution_control_state
*,
2437 struct frame_info
*);
2439 static void stop_stepping (struct execution_control_state
*ecs
);
2440 static void prepare_to_wait (struct execution_control_state
*ecs
);
2441 static void keep_going (struct execution_control_state
*ecs
);
2442 static void process_event_stop_test (struct execution_control_state
*ecs
);
2443 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
2445 /* Callback for iterate over threads. If the thread is stopped, but
2446 the user/frontend doesn't know about that yet, go through
2447 normal_stop, as if the thread had just stopped now. ARG points at
2448 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2449 ptid_is_pid(PTID) is true, applies to all threads of the process
2450 pointed at by PTID. Otherwise, apply only to the thread pointed by
2454 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2456 ptid_t ptid
= * (ptid_t
*) arg
;
2458 if ((ptid_equal (info
->ptid
, ptid
)
2459 || ptid_equal (minus_one_ptid
, ptid
)
2460 || (ptid_is_pid (ptid
)
2461 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2462 && is_running (info
->ptid
)
2463 && !is_executing (info
->ptid
))
2465 struct cleanup
*old_chain
;
2466 struct execution_control_state ecss
;
2467 struct execution_control_state
*ecs
= &ecss
;
2469 memset (ecs
, 0, sizeof (*ecs
));
2471 old_chain
= make_cleanup_restore_current_thread ();
2473 /* Go through handle_inferior_event/normal_stop, so we always
2474 have consistent output as if the stop event had been
2476 ecs
->ptid
= info
->ptid
;
2477 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2478 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2479 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2481 handle_inferior_event (ecs
);
2483 if (!ecs
->wait_some_more
)
2485 struct thread_info
*tp
;
2489 /* Finish off the continuations. */
2490 tp
= inferior_thread ();
2491 do_all_intermediate_continuations_thread (tp
, 1);
2492 do_all_continuations_thread (tp
, 1);
2495 do_cleanups (old_chain
);
2501 /* This function is attached as a "thread_stop_requested" observer.
2502 Cleanup local state that assumed the PTID was to be resumed, and
2503 report the stop to the frontend. */
2506 infrun_thread_stop_requested (ptid_t ptid
)
2508 struct displaced_step_inferior_state
*displaced
;
2510 /* PTID was requested to stop. Remove it from the displaced
2511 stepping queue, so we don't try to resume it automatically. */
2513 for (displaced
= displaced_step_inferior_states
;
2515 displaced
= displaced
->next
)
2517 struct displaced_step_request
*it
, **prev_next_p
;
2519 it
= displaced
->step_request_queue
;
2520 prev_next_p
= &displaced
->step_request_queue
;
2523 if (ptid_match (it
->ptid
, ptid
))
2525 *prev_next_p
= it
->next
;
2531 prev_next_p
= &it
->next
;
2538 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2542 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2544 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2545 nullify_last_target_wait_ptid ();
2548 /* Callback for iterate_over_threads. */
2551 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
2553 if (is_exited (info
->ptid
))
2556 delete_step_resume_breakpoint (info
);
2557 delete_exception_resume_breakpoint (info
);
2561 /* In all-stop, delete the step resume breakpoint of any thread that
2562 had one. In non-stop, delete the step resume breakpoint of the
2563 thread that just stopped. */
2566 delete_step_thread_step_resume_breakpoint (void)
2568 if (!target_has_execution
2569 || ptid_equal (inferior_ptid
, null_ptid
))
2570 /* If the inferior has exited, we have already deleted the step
2571 resume breakpoints out of GDB's lists. */
2576 /* If in non-stop mode, only delete the step-resume or
2577 longjmp-resume breakpoint of the thread that just stopped
2579 struct thread_info
*tp
= inferior_thread ();
2581 delete_step_resume_breakpoint (tp
);
2582 delete_exception_resume_breakpoint (tp
);
2585 /* In all-stop mode, delete all step-resume and longjmp-resume
2586 breakpoints of any thread that had them. */
2587 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
2590 /* A cleanup wrapper. */
2593 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
2595 delete_step_thread_step_resume_breakpoint ();
2598 /* Pretty print the results of target_wait, for debugging purposes. */
2601 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
2602 const struct target_waitstatus
*ws
)
2604 char *status_string
= target_waitstatus_to_string (ws
);
2605 struct ui_file
*tmp_stream
= mem_fileopen ();
2608 /* The text is split over several lines because it was getting too long.
2609 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2610 output as a unit; we want only one timestamp printed if debug_timestamp
2613 fprintf_unfiltered (tmp_stream
,
2614 "infrun: target_wait (%d", ptid_get_pid (waiton_ptid
));
2615 if (ptid_get_pid (waiton_ptid
) != -1)
2616 fprintf_unfiltered (tmp_stream
,
2617 " [%s]", target_pid_to_str (waiton_ptid
));
2618 fprintf_unfiltered (tmp_stream
, ", status) =\n");
2619 fprintf_unfiltered (tmp_stream
,
2620 "infrun: %d [%s],\n",
2621 ptid_get_pid (result_ptid
),
2622 target_pid_to_str (result_ptid
));
2623 fprintf_unfiltered (tmp_stream
,
2627 text
= ui_file_xstrdup (tmp_stream
, NULL
);
2629 /* This uses %s in part to handle %'s in the text, but also to avoid
2630 a gcc error: the format attribute requires a string literal. */
2631 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
2633 xfree (status_string
);
2635 ui_file_delete (tmp_stream
);
2638 /* Prepare and stabilize the inferior for detaching it. E.g.,
2639 detaching while a thread is displaced stepping is a recipe for
2640 crashing it, as nothing would readjust the PC out of the scratch
2644 prepare_for_detach (void)
2646 struct inferior
*inf
= current_inferior ();
2647 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
2648 struct cleanup
*old_chain_1
;
2649 struct displaced_step_inferior_state
*displaced
;
2651 displaced
= get_displaced_stepping_state (inf
->pid
);
2653 /* Is any thread of this process displaced stepping? If not,
2654 there's nothing else to do. */
2655 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
2659 fprintf_unfiltered (gdb_stdlog
,
2660 "displaced-stepping in-process while detaching");
2662 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
2665 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
2667 struct cleanup
*old_chain_2
;
2668 struct execution_control_state ecss
;
2669 struct execution_control_state
*ecs
;
2672 memset (ecs
, 0, sizeof (*ecs
));
2674 overlay_cache_invalid
= 1;
2676 if (deprecated_target_wait_hook
)
2677 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
2679 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
2682 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
2684 /* If an error happens while handling the event, propagate GDB's
2685 knowledge of the executing state to the frontend/user running
2687 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
2690 /* Now figure out what to do with the result of the result. */
2691 handle_inferior_event (ecs
);
2693 /* No error, don't finish the state yet. */
2694 discard_cleanups (old_chain_2
);
2696 /* Breakpoints and watchpoints are not installed on the target
2697 at this point, and signals are passed directly to the
2698 inferior, so this must mean the process is gone. */
2699 if (!ecs
->wait_some_more
)
2701 discard_cleanups (old_chain_1
);
2702 error (_("Program exited while detaching"));
2706 discard_cleanups (old_chain_1
);
2709 /* Wait for control to return from inferior to debugger.
2711 If inferior gets a signal, we may decide to start it up again
2712 instead of returning. That is why there is a loop in this function.
2713 When this function actually returns it means the inferior
2714 should be left stopped and GDB should read more commands. */
2717 wait_for_inferior (void)
2719 struct cleanup
*old_cleanups
;
2723 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
2726 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
2730 struct execution_control_state ecss
;
2731 struct execution_control_state
*ecs
= &ecss
;
2732 struct cleanup
*old_chain
;
2734 memset (ecs
, 0, sizeof (*ecs
));
2736 overlay_cache_invalid
= 1;
2738 if (deprecated_target_wait_hook
)
2739 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
2741 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
2744 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2746 /* If an error happens while handling the event, propagate GDB's
2747 knowledge of the executing state to the frontend/user running
2749 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2751 /* Now figure out what to do with the result of the result. */
2752 handle_inferior_event (ecs
);
2754 /* No error, don't finish the state yet. */
2755 discard_cleanups (old_chain
);
2757 if (!ecs
->wait_some_more
)
2761 do_cleanups (old_cleanups
);
2764 /* Asynchronous version of wait_for_inferior. It is called by the
2765 event loop whenever a change of state is detected on the file
2766 descriptor corresponding to the target. It can be called more than
2767 once to complete a single execution command. In such cases we need
2768 to keep the state in a global variable ECSS. If it is the last time
2769 that this function is called for a single execution command, then
2770 report to the user that the inferior has stopped, and do the
2771 necessary cleanups. */
2774 fetch_inferior_event (void *client_data
)
2776 struct execution_control_state ecss
;
2777 struct execution_control_state
*ecs
= &ecss
;
2778 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
2779 struct cleanup
*ts_old_chain
;
2780 int was_sync
= sync_execution
;
2783 memset (ecs
, 0, sizeof (*ecs
));
2785 /* We're handling a live event, so make sure we're doing live
2786 debugging. If we're looking at traceframes while the target is
2787 running, we're going to need to get back to that mode after
2788 handling the event. */
2791 make_cleanup_restore_current_traceframe ();
2792 set_current_traceframe (-1);
2796 /* In non-stop mode, the user/frontend should not notice a thread
2797 switch due to internal events. Make sure we reverse to the
2798 user selected thread and frame after handling the event and
2799 running any breakpoint commands. */
2800 make_cleanup_restore_current_thread ();
2802 overlay_cache_invalid
= 1;
2804 make_cleanup_restore_integer (&execution_direction
);
2805 execution_direction
= target_execution_direction ();
2807 if (deprecated_target_wait_hook
)
2809 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2811 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2814 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2816 /* If an error happens while handling the event, propagate GDB's
2817 knowledge of the executing state to the frontend/user running
2820 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2822 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
2824 /* Get executed before make_cleanup_restore_current_thread above to apply
2825 still for the thread which has thrown the exception. */
2826 make_bpstat_clear_actions_cleanup ();
2828 /* Now figure out what to do with the result of the result. */
2829 handle_inferior_event (ecs
);
2831 if (!ecs
->wait_some_more
)
2833 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2835 delete_step_thread_step_resume_breakpoint ();
2837 /* We may not find an inferior if this was a process exit. */
2838 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
2841 if (target_has_execution
2842 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
2843 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2844 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2845 && ecs
->event_thread
->step_multi
2846 && ecs
->event_thread
->control
.stop_step
)
2847 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
2850 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2855 /* No error, don't finish the thread states yet. */
2856 discard_cleanups (ts_old_chain
);
2858 /* Revert thread and frame. */
2859 do_cleanups (old_chain
);
2861 /* If the inferior was in sync execution mode, and now isn't,
2862 restore the prompt (a synchronous execution command has finished,
2863 and we're ready for input). */
2864 if (interpreter_async
&& was_sync
&& !sync_execution
)
2865 display_gdb_prompt (0);
2869 && exec_done_display_p
2870 && (ptid_equal (inferior_ptid
, null_ptid
)
2871 || !is_running (inferior_ptid
)))
2872 printf_unfiltered (_("completed.\n"));
2875 /* Record the frame and location we're currently stepping through. */
2877 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
2879 struct thread_info
*tp
= inferior_thread ();
2881 tp
->control
.step_frame_id
= get_frame_id (frame
);
2882 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
2884 tp
->current_symtab
= sal
.symtab
;
2885 tp
->current_line
= sal
.line
;
2888 /* Clear context switchable stepping state. */
2891 init_thread_stepping_state (struct thread_info
*tss
)
2893 tss
->stepping_over_breakpoint
= 0;
2894 tss
->step_after_step_resume_breakpoint
= 0;
2897 /* Return the cached copy of the last pid/waitstatus returned by
2898 target_wait()/deprecated_target_wait_hook(). The data is actually
2899 cached by handle_inferior_event(), which gets called immediately
2900 after target_wait()/deprecated_target_wait_hook(). */
2903 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
2905 *ptidp
= target_last_wait_ptid
;
2906 *status
= target_last_waitstatus
;
2910 nullify_last_target_wait_ptid (void)
2912 target_last_wait_ptid
= minus_one_ptid
;
2915 /* Switch thread contexts. */
2918 context_switch (ptid_t ptid
)
2920 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
2922 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
2923 target_pid_to_str (inferior_ptid
));
2924 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
2925 target_pid_to_str (ptid
));
2928 switch_to_thread (ptid
);
2932 adjust_pc_after_break (struct execution_control_state
*ecs
)
2934 struct regcache
*regcache
;
2935 struct gdbarch
*gdbarch
;
2936 struct address_space
*aspace
;
2937 CORE_ADDR breakpoint_pc
;
2939 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2940 we aren't, just return.
2942 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2943 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2944 implemented by software breakpoints should be handled through the normal
2947 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2948 different signals (SIGILL or SIGEMT for instance), but it is less
2949 clear where the PC is pointing afterwards. It may not match
2950 gdbarch_decr_pc_after_break. I don't know any specific target that
2951 generates these signals at breakpoints (the code has been in GDB since at
2952 least 1992) so I can not guess how to handle them here.
2954 In earlier versions of GDB, a target with
2955 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2956 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2957 target with both of these set in GDB history, and it seems unlikely to be
2958 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2960 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
2963 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
2966 /* In reverse execution, when a breakpoint is hit, the instruction
2967 under it has already been de-executed. The reported PC always
2968 points at the breakpoint address, so adjusting it further would
2969 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2972 B1 0x08000000 : INSN1
2973 B2 0x08000001 : INSN2
2975 PC -> 0x08000003 : INSN4
2977 Say you're stopped at 0x08000003 as above. Reverse continuing
2978 from that point should hit B2 as below. Reading the PC when the
2979 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2980 been de-executed already.
2982 B1 0x08000000 : INSN1
2983 B2 PC -> 0x08000001 : INSN2
2987 We can't apply the same logic as for forward execution, because
2988 we would wrongly adjust the PC to 0x08000000, since there's a
2989 breakpoint at PC - 1. We'd then report a hit on B1, although
2990 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2992 if (execution_direction
== EXEC_REVERSE
)
2995 /* If this target does not decrement the PC after breakpoints, then
2996 we have nothing to do. */
2997 regcache
= get_thread_regcache (ecs
->ptid
);
2998 gdbarch
= get_regcache_arch (regcache
);
2999 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
3002 aspace
= get_regcache_aspace (regcache
);
3004 /* Find the location where (if we've hit a breakpoint) the
3005 breakpoint would be. */
3006 breakpoint_pc
= regcache_read_pc (regcache
)
3007 - gdbarch_decr_pc_after_break (gdbarch
);
3009 /* Check whether there actually is a software breakpoint inserted at
3012 If in non-stop mode, a race condition is possible where we've
3013 removed a breakpoint, but stop events for that breakpoint were
3014 already queued and arrive later. To suppress those spurious
3015 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3016 and retire them after a number of stop events are reported. */
3017 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3018 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3020 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
3023 record_full_gdb_operation_disable_set ();
3025 /* When using hardware single-step, a SIGTRAP is reported for both
3026 a completed single-step and a software breakpoint. Need to
3027 differentiate between the two, as the latter needs adjusting
3028 but the former does not.
3030 The SIGTRAP can be due to a completed hardware single-step only if
3031 - we didn't insert software single-step breakpoints
3032 - the thread to be examined is still the current thread
3033 - this thread is currently being stepped
3035 If any of these events did not occur, we must have stopped due
3036 to hitting a software breakpoint, and have to back up to the
3039 As a special case, we could have hardware single-stepped a
3040 software breakpoint. In this case (prev_pc == breakpoint_pc),
3041 we also need to back up to the breakpoint address. */
3043 if (singlestep_breakpoints_inserted_p
3044 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
3045 || !currently_stepping (ecs
->event_thread
)
3046 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
3047 regcache_write_pc (regcache
, breakpoint_pc
);
3049 do_cleanups (old_cleanups
);
3054 init_infwait_state (void)
3056 waiton_ptid
= pid_to_ptid (-1);
3057 infwait_state
= infwait_normal_state
;
3061 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3063 for (frame
= get_prev_frame (frame
);
3065 frame
= get_prev_frame (frame
))
3067 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3069 if (get_frame_type (frame
) != INLINE_FRAME
)
3076 /* Auxiliary function that handles syscall entry/return events.
3077 It returns 1 if the inferior should keep going (and GDB
3078 should ignore the event), or 0 if the event deserves to be
3082 handle_syscall_event (struct execution_control_state
*ecs
)
3084 struct regcache
*regcache
;
3087 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3088 context_switch (ecs
->ptid
);
3090 regcache
= get_thread_regcache (ecs
->ptid
);
3091 syscall_number
= ecs
->ws
.value
.syscall_number
;
3092 stop_pc
= regcache_read_pc (regcache
);
3094 if (catch_syscall_enabled () > 0
3095 && catching_syscall_number (syscall_number
) > 0)
3097 enum bpstat_signal_value sval
;
3100 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3103 ecs
->event_thread
->control
.stop_bpstat
3104 = bpstat_stop_status (get_regcache_aspace (regcache
),
3105 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3107 sval
= bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
3109 ecs
->random_signal
= sval
== BPSTAT_SIGNAL_NO
;
3111 if (!ecs
->random_signal
)
3113 /* Catchpoint hit. */
3118 /* If no catchpoint triggered for this, then keep going. */
3123 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3126 fill_in_stop_func (struct gdbarch
*gdbarch
,
3127 struct execution_control_state
*ecs
)
3129 if (!ecs
->stop_func_filled_in
)
3131 /* Don't care about return value; stop_func_start and stop_func_name
3132 will both be 0 if it doesn't work. */
3133 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3134 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3135 ecs
->stop_func_start
3136 += gdbarch_deprecated_function_start_offset (gdbarch
);
3138 ecs
->stop_func_filled_in
= 1;
3142 /* Given an execution control state that has been freshly filled in
3143 by an event from the inferior, figure out what it means and take
3144 appropriate action. */
3147 handle_inferior_event (struct execution_control_state
*ecs
)
3149 struct frame_info
*frame
;
3150 struct gdbarch
*gdbarch
;
3151 int stopped_by_watchpoint
;
3152 int stepped_after_stopped_by_watchpoint
= 0;
3153 enum stop_kind stop_soon
;
3155 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3157 /* We had an event in the inferior, but we are not interested in
3158 handling it at this level. The lower layers have already
3159 done what needs to be done, if anything.
3161 One of the possible circumstances for this is when the
3162 inferior produces output for the console. The inferior has
3163 not stopped, and we are ignoring the event. Another possible
3164 circumstance is any event which the lower level knows will be
3165 reported multiple times without an intervening resume. */
3167 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3168 prepare_to_wait (ecs
);
3172 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3173 && target_can_async_p () && !sync_execution
)
3175 /* There were no unwaited-for children left in the target, but,
3176 we're not synchronously waiting for events either. Just
3177 ignore. Otherwise, if we were running a synchronous
3178 execution command, we need to cancel it and give the user
3179 back the terminal. */
3181 fprintf_unfiltered (gdb_stdlog
,
3182 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3183 prepare_to_wait (ecs
);
3187 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3188 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3189 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
3191 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3194 stop_soon
= inf
->control
.stop_soon
;
3197 stop_soon
= NO_STOP_QUIETLY
;
3199 /* Cache the last pid/waitstatus. */
3200 target_last_wait_ptid
= ecs
->ptid
;
3201 target_last_waitstatus
= ecs
->ws
;
3203 /* Always clear state belonging to the previous time we stopped. */
3204 stop_stack_dummy
= STOP_NONE
;
3206 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3208 /* No unwaited-for children left. IOW, all resumed children
3211 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3213 stop_print_frame
= 0;
3214 stop_stepping (ecs
);
3218 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3219 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
3221 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3222 /* If it's a new thread, add it to the thread database. */
3223 if (ecs
->event_thread
== NULL
)
3224 ecs
->event_thread
= add_thread (ecs
->ptid
);
3226 /* Disable range stepping. If the next step request could use a
3227 range, this will be end up re-enabled then. */
3228 ecs
->event_thread
->control
.may_range_step
= 0;
3231 /* Dependent on valid ECS->EVENT_THREAD. */
3232 adjust_pc_after_break (ecs
);
3234 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3235 reinit_frame_cache ();
3237 breakpoint_retire_moribund ();
3239 /* First, distinguish signals caused by the debugger from signals
3240 that have to do with the program's own actions. Note that
3241 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3242 on the operating system version. Here we detect when a SIGILL or
3243 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3244 something similar for SIGSEGV, since a SIGSEGV will be generated
3245 when we're trying to execute a breakpoint instruction on a
3246 non-executable stack. This happens for call dummy breakpoints
3247 for architectures like SPARC that place call dummies on the
3249 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3250 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3251 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3252 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3254 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3256 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3257 regcache_read_pc (regcache
)))
3260 fprintf_unfiltered (gdb_stdlog
,
3261 "infrun: Treating signal as SIGTRAP\n");
3262 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3266 /* Mark the non-executing threads accordingly. In all-stop, all
3267 threads of all processes are stopped when we get any event
3268 reported. In non-stop mode, only the event thread stops. If
3269 we're handling a process exit in non-stop mode, there's nothing
3270 to do, as threads of the dead process are gone, and threads of
3271 any other process were left running. */
3273 set_executing (minus_one_ptid
, 0);
3274 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3275 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3276 set_executing (ecs
->ptid
, 0);
3278 switch (infwait_state
)
3280 case infwait_thread_hop_state
:
3282 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
3285 case infwait_normal_state
:
3287 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
3290 case infwait_step_watch_state
:
3292 fprintf_unfiltered (gdb_stdlog
,
3293 "infrun: infwait_step_watch_state\n");
3295 stepped_after_stopped_by_watchpoint
= 1;
3298 case infwait_nonstep_watch_state
:
3300 fprintf_unfiltered (gdb_stdlog
,
3301 "infrun: infwait_nonstep_watch_state\n");
3302 insert_breakpoints ();
3304 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3305 handle things like signals arriving and other things happening
3306 in combination correctly? */
3307 stepped_after_stopped_by_watchpoint
= 1;
3311 internal_error (__FILE__
, __LINE__
, _("bad switch"));
3314 infwait_state
= infwait_normal_state
;
3315 waiton_ptid
= pid_to_ptid (-1);
3317 switch (ecs
->ws
.kind
)
3319 case TARGET_WAITKIND_LOADED
:
3321 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3322 /* Ignore gracefully during startup of the inferior, as it might
3323 be the shell which has just loaded some objects, otherwise
3324 add the symbols for the newly loaded objects. Also ignore at
3325 the beginning of an attach or remote session; we will query
3326 the full list of libraries once the connection is
3328 if (stop_soon
== NO_STOP_QUIETLY
)
3330 struct regcache
*regcache
;
3331 enum bpstat_signal_value sval
;
3333 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3334 context_switch (ecs
->ptid
);
3335 regcache
= get_thread_regcache (ecs
->ptid
);
3337 handle_solib_event ();
3339 ecs
->event_thread
->control
.stop_bpstat
3340 = bpstat_stop_status (get_regcache_aspace (regcache
),
3341 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3344 = bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
3346 ecs
->random_signal
= sval
== BPSTAT_SIGNAL_NO
;
3348 if (!ecs
->random_signal
)
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. But stop if
3374 we're attaching or setting up a remote connection. */
3375 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3377 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3378 context_switch (ecs
->ptid
);
3380 /* Loading of shared libraries might have changed breakpoint
3381 addresses. Make sure new breakpoints are inserted. */
3382 if (stop_soon
== NO_STOP_QUIETLY
3383 && !breakpoints_always_inserted_mode ())
3384 insert_breakpoints ();
3385 resume (0, GDB_SIGNAL_0
);
3386 prepare_to_wait (ecs
);
3392 case TARGET_WAITKIND_SPURIOUS
:
3394 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3395 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3396 context_switch (ecs
->ptid
);
3397 resume (0, GDB_SIGNAL_0
);
3398 prepare_to_wait (ecs
);
3401 case TARGET_WAITKIND_EXITED
:
3402 case TARGET_WAITKIND_SIGNALLED
:
3405 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3406 fprintf_unfiltered (gdb_stdlog
,
3407 "infrun: TARGET_WAITKIND_EXITED\n");
3409 fprintf_unfiltered (gdb_stdlog
,
3410 "infrun: TARGET_WAITKIND_SIGNALLED\n");
3413 inferior_ptid
= ecs
->ptid
;
3414 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3415 set_current_program_space (current_inferior ()->pspace
);
3416 handle_vfork_child_exec_or_exit (0);
3417 target_terminal_ours (); /* Must do this before mourn anyway. */
3419 /* Clearing any previous state of convenience variables. */
3420 clear_exit_convenience_vars ();
3422 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3424 /* Record the exit code in the convenience variable $_exitcode, so
3425 that the user can inspect this again later. */
3426 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3427 (LONGEST
) ecs
->ws
.value
.integer
);
3429 /* Also record this in the inferior itself. */
3430 current_inferior ()->has_exit_code
= 1;
3431 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3433 print_exited_reason (ecs
->ws
.value
.integer
);
3437 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3438 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3440 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
3442 /* Set the value of the internal variable $_exitsignal,
3443 which holds the signal uncaught by the inferior. */
3444 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
3445 gdbarch_gdb_signal_to_target (gdbarch
,
3446 ecs
->ws
.value
.sig
));
3450 /* We don't have access to the target's method used for
3451 converting between signal numbers (GDB's internal
3452 representation <-> target's representation).
3453 Therefore, we cannot do a good job at displaying this
3454 information to the user. It's better to just warn
3455 her about it (if infrun debugging is enabled), and
3458 fprintf_filtered (gdb_stdlog
, _("\
3459 Cannot fill $_exitsignal with the correct signal number.\n"));
3462 print_signal_exited_reason (ecs
->ws
.value
.sig
);
3465 gdb_flush (gdb_stdout
);
3466 target_mourn_inferior ();
3467 singlestep_breakpoints_inserted_p
= 0;
3468 cancel_single_step_breakpoints ();
3469 stop_print_frame
= 0;
3470 stop_stepping (ecs
);
3473 /* The following are the only cases in which we keep going;
3474 the above cases end in a continue or goto. */
3475 case TARGET_WAITKIND_FORKED
:
3476 case TARGET_WAITKIND_VFORKED
:
3479 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3480 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3482 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
3485 /* Check whether the inferior is displaced stepping. */
3487 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3488 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3489 struct displaced_step_inferior_state
*displaced
3490 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3492 /* If checking displaced stepping is supported, and thread
3493 ecs->ptid is displaced stepping. */
3494 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3496 struct inferior
*parent_inf
3497 = find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3498 struct regcache
*child_regcache
;
3499 CORE_ADDR parent_pc
;
3501 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3502 indicating that the displaced stepping of syscall instruction
3503 has been done. Perform cleanup for parent process here. Note
3504 that this operation also cleans up the child process for vfork,
3505 because their pages are shared. */
3506 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3508 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3510 /* Restore scratch pad for child process. */
3511 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3514 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3515 the child's PC is also within the scratchpad. Set the child's PC
3516 to the parent's PC value, which has already been fixed up.
3517 FIXME: we use the parent's aspace here, although we're touching
3518 the child, because the child hasn't been added to the inferior
3519 list yet at this point. */
3522 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3524 parent_inf
->aspace
);
3525 /* Read PC value of parent process. */
3526 parent_pc
= regcache_read_pc (regcache
);
3528 if (debug_displaced
)
3529 fprintf_unfiltered (gdb_stdlog
,
3530 "displaced: write child pc from %s to %s\n",
3532 regcache_read_pc (child_regcache
)),
3533 paddress (gdbarch
, parent_pc
));
3535 regcache_write_pc (child_regcache
, parent_pc
);
3539 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3540 context_switch (ecs
->ptid
);
3542 /* Immediately detach breakpoints from the child before there's
3543 any chance of letting the user delete breakpoints from the
3544 breakpoint lists. If we don't do this early, it's easy to
3545 leave left over traps in the child, vis: "break foo; catch
3546 fork; c; <fork>; del; c; <child calls foo>". We only follow
3547 the fork on the last `continue', and by that time the
3548 breakpoint at "foo" is long gone from the breakpoint table.
3549 If we vforked, then we don't need to unpatch here, since both
3550 parent and child are sharing the same memory pages; we'll
3551 need to unpatch at follow/detach time instead to be certain
3552 that new breakpoints added between catchpoint hit time and
3553 vfork follow are detached. */
3554 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3556 /* This won't actually modify the breakpoint list, but will
3557 physically remove the breakpoints from the child. */
3558 detach_breakpoints (ecs
->ws
.value
.related_pid
);
3561 if (singlestep_breakpoints_inserted_p
)
3563 /* Pull the single step breakpoints out of the target. */
3564 remove_single_step_breakpoints ();
3565 singlestep_breakpoints_inserted_p
= 0;
3568 /* In case the event is caught by a catchpoint, remember that
3569 the event is to be followed at the next resume of the thread,
3570 and not immediately. */
3571 ecs
->event_thread
->pending_follow
= ecs
->ws
;
3573 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3575 ecs
->event_thread
->control
.stop_bpstat
3576 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3577 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3579 /* Note that we're interested in knowing the bpstat actually
3580 causes a stop, not just if it may explain the signal.
3581 Software watchpoints, for example, always appear in the
3584 = !bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
);
3586 /* If no catchpoint triggered for this, then keep going. */
3587 if (ecs
->random_signal
)
3593 = (follow_fork_mode_string
== follow_fork_mode_child
);
3595 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3597 should_resume
= follow_fork ();
3600 child
= ecs
->ws
.value
.related_pid
;
3602 /* In non-stop mode, also resume the other branch. */
3603 if (non_stop
&& !detach_fork
)
3606 switch_to_thread (parent
);
3608 switch_to_thread (child
);
3610 ecs
->event_thread
= inferior_thread ();
3611 ecs
->ptid
= inferior_ptid
;
3616 switch_to_thread (child
);
3618 switch_to_thread (parent
);
3620 ecs
->event_thread
= inferior_thread ();
3621 ecs
->ptid
= inferior_ptid
;
3626 stop_stepping (ecs
);
3629 process_event_stop_test (ecs
);
3632 case TARGET_WAITKIND_VFORK_DONE
:
3633 /* Done with the shared memory region. Re-insert breakpoints in
3634 the parent, and keep going. */
3637 fprintf_unfiltered (gdb_stdlog
,
3638 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3640 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3641 context_switch (ecs
->ptid
);
3643 current_inferior ()->waiting_for_vfork_done
= 0;
3644 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
3645 /* This also takes care of reinserting breakpoints in the
3646 previously locked inferior. */
3650 case TARGET_WAITKIND_EXECD
:
3652 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
3654 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3655 context_switch (ecs
->ptid
);
3657 singlestep_breakpoints_inserted_p
= 0;
3658 cancel_single_step_breakpoints ();
3660 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3662 /* Do whatever is necessary to the parent branch of the vfork. */
3663 handle_vfork_child_exec_or_exit (1);
3665 /* This causes the eventpoints and symbol table to be reset.
3666 Must do this now, before trying to determine whether to
3668 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
3670 ecs
->event_thread
->control
.stop_bpstat
3671 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3672 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3674 = (bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
3676 == BPSTAT_SIGNAL_NO
);
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 (ecs
->random_signal
)
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
;
3723 case TARGET_WAITKIND_NO_HISTORY
:
3725 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
3726 /* Reverse execution: target ran out of history info. */
3728 /* Pull the single step breakpoints out of the target. */
3729 if (singlestep_breakpoints_inserted_p
)
3731 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3732 context_switch (ecs
->ptid
);
3733 remove_single_step_breakpoints ();
3734 singlestep_breakpoints_inserted_p
= 0;
3736 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3737 print_no_history_reason ();
3738 stop_stepping (ecs
);
3742 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
3744 /* Do we need to clean up the state of a thread that has
3745 completed a displaced single-step? (Doing so usually affects
3746 the PC, so do it here, before we set stop_pc.) */
3747 displaced_step_fixup (ecs
->ptid
,
3748 ecs
->event_thread
->suspend
.stop_signal
);
3750 /* If we either finished a single-step or hit a breakpoint, but
3751 the user wanted this thread to be stopped, pretend we got a
3752 SIG0 (generic unsignaled stop). */
3754 if (ecs
->event_thread
->stop_requested
3755 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3756 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3759 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3763 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3764 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3765 struct cleanup
*old_chain
= save_inferior_ptid ();
3767 inferior_ptid
= ecs
->ptid
;
3769 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
3770 paddress (gdbarch
, stop_pc
));
3771 if (target_stopped_by_watchpoint ())
3775 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
3777 if (target_stopped_data_address (¤t_target
, &addr
))
3778 fprintf_unfiltered (gdb_stdlog
,
3779 "infrun: stopped data address = %s\n",
3780 paddress (gdbarch
, addr
));
3782 fprintf_unfiltered (gdb_stdlog
,
3783 "infrun: (no data address available)\n");
3786 do_cleanups (old_chain
);
3789 if (stepping_past_singlestep_breakpoint
)
3791 gdb_assert (singlestep_breakpoints_inserted_p
);
3792 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
3793 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
3795 stepping_past_singlestep_breakpoint
= 0;
3797 /* We've either finished single-stepping past the single-step
3798 breakpoint, or stopped for some other reason. It would be nice if
3799 we could tell, but we can't reliably. */
3800 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3803 fprintf_unfiltered (gdb_stdlog
,
3804 "infrun: stepping_past_"
3805 "singlestep_breakpoint\n");
3806 /* Pull the single step breakpoints out of the target. */
3807 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3808 context_switch (ecs
->ptid
);
3809 remove_single_step_breakpoints ();
3810 singlestep_breakpoints_inserted_p
= 0;
3812 ecs
->event_thread
->control
.trap_expected
= 0;
3814 context_switch (saved_singlestep_ptid
);
3815 if (deprecated_context_hook
)
3816 deprecated_context_hook (pid_to_thread_id (saved_singlestep_ptid
));
3818 resume (1, GDB_SIGNAL_0
);
3819 prepare_to_wait (ecs
);
3824 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
3826 /* In non-stop mode, there's never a deferred_step_ptid set. */
3827 gdb_assert (!non_stop
);
3829 /* If we stopped for some other reason than single-stepping, ignore
3830 the fact that we were supposed to switch back. */
3831 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3834 fprintf_unfiltered (gdb_stdlog
,
3835 "infrun: handling deferred step\n");
3837 /* Pull the single step breakpoints out of the target. */
3838 if (singlestep_breakpoints_inserted_p
)
3840 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3841 context_switch (ecs
->ptid
);
3842 remove_single_step_breakpoints ();
3843 singlestep_breakpoints_inserted_p
= 0;
3846 ecs
->event_thread
->control
.trap_expected
= 0;
3848 context_switch (deferred_step_ptid
);
3849 deferred_step_ptid
= null_ptid
;
3850 /* Suppress spurious "Switching to ..." message. */
3851 previous_inferior_ptid
= inferior_ptid
;
3853 resume (1, GDB_SIGNAL_0
);
3854 prepare_to_wait (ecs
);
3858 deferred_step_ptid
= null_ptid
;
3861 /* See if a thread hit a thread-specific breakpoint that was meant for
3862 another thread. If so, then step that thread past the breakpoint,
3865 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3867 int thread_hop_needed
= 0;
3868 struct address_space
*aspace
=
3869 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
3871 /* Check if a regular breakpoint has been hit before checking
3872 for a potential single step breakpoint. Otherwise, GDB will
3873 not see this breakpoint hit when stepping onto breakpoints. */
3874 if (regular_breakpoint_inserted_here_p (aspace
, stop_pc
))
3876 if (!breakpoint_thread_match (aspace
, stop_pc
, ecs
->ptid
))
3877 thread_hop_needed
= 1;
3879 else if (singlestep_breakpoints_inserted_p
)
3881 /* We have not context switched yet, so this should be true
3882 no matter which thread hit the singlestep breakpoint. */
3883 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
3885 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
3887 target_pid_to_str (ecs
->ptid
));
3889 /* The call to in_thread_list is necessary because PTIDs sometimes
3890 change when we go from single-threaded to multi-threaded. If
3891 the singlestep_ptid is still in the list, assume that it is
3892 really different from ecs->ptid. */
3893 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
3894 && in_thread_list (singlestep_ptid
))
3896 /* If the PC of the thread we were trying to single-step
3897 has changed, discard this event (which we were going
3898 to ignore anyway), and pretend we saw that thread
3899 trap. This prevents us continuously moving the
3900 single-step breakpoint forward, one instruction at a
3901 time. If the PC has changed, then the thread we were
3902 trying to single-step has trapped or been signalled,
3903 but the event has not been reported to GDB yet.
3905 There might be some cases where this loses signal
3906 information, if a signal has arrived at exactly the
3907 same time that the PC changed, but this is the best
3908 we can do with the information available. Perhaps we
3909 should arrange to report all events for all threads
3910 when they stop, or to re-poll the remote looking for
3911 this particular thread (i.e. temporarily enable
3914 CORE_ADDR new_singlestep_pc
3915 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
3917 if (new_singlestep_pc
!= singlestep_pc
)
3919 enum gdb_signal stop_signal
;
3922 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
3923 " but expected thread advanced also\n");
3925 /* The current context still belongs to
3926 singlestep_ptid. Don't swap here, since that's
3927 the context we want to use. Just fudge our
3928 state and continue. */
3929 stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
3930 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3931 ecs
->ptid
= singlestep_ptid
;
3932 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3933 ecs
->event_thread
->suspend
.stop_signal
= stop_signal
;
3934 stop_pc
= new_singlestep_pc
;
3939 fprintf_unfiltered (gdb_stdlog
,
3940 "infrun: unexpected thread\n");
3942 thread_hop_needed
= 1;
3943 stepping_past_singlestep_breakpoint
= 1;
3944 saved_singlestep_ptid
= singlestep_ptid
;
3949 if (thread_hop_needed
)
3951 struct regcache
*thread_regcache
;
3952 int remove_status
= 0;
3955 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
3957 /* Switch context before touching inferior memory, the
3958 previous thread may have exited. */
3959 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
3960 context_switch (ecs
->ptid
);
3962 /* Saw a breakpoint, but it was hit by the wrong thread.
3965 if (singlestep_breakpoints_inserted_p
)
3967 /* Pull the single step breakpoints out of the target. */
3968 remove_single_step_breakpoints ();
3969 singlestep_breakpoints_inserted_p
= 0;
3972 /* If the arch can displace step, don't remove the
3974 thread_regcache
= get_thread_regcache (ecs
->ptid
);
3975 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
3976 remove_status
= remove_breakpoints ();
3978 /* Did we fail to remove breakpoints? If so, try
3979 to set the PC past the bp. (There's at least
3980 one situation in which we can fail to remove
3981 the bp's: On HP-UX's that use ttrace, we can't
3982 change the address space of a vforking child
3983 process until the child exits (well, okay, not
3984 then either :-) or execs. */
3985 if (remove_status
!= 0)
3986 error (_("Cannot step over breakpoint hit in wrong thread"));
3991 /* Only need to require the next event from this
3992 thread in all-stop mode. */
3993 waiton_ptid
= ecs
->ptid
;
3994 infwait_state
= infwait_thread_hop_state
;
3997 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4004 /* See if something interesting happened to the non-current thread. If
4005 so, then switch to that thread. */
4006 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4009 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
4011 context_switch (ecs
->ptid
);
4013 if (deprecated_context_hook
)
4014 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
4017 /* At this point, get hold of the now-current thread's frame. */
4018 frame
= get_current_frame ();
4019 gdbarch
= get_frame_arch (frame
);
4021 if (singlestep_breakpoints_inserted_p
)
4023 /* Pull the single step breakpoints out of the target. */
4024 remove_single_step_breakpoints ();
4025 singlestep_breakpoints_inserted_p
= 0;
4028 if (stepped_after_stopped_by_watchpoint
)
4029 stopped_by_watchpoint
= 0;
4031 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
4033 /* If necessary, step over this watchpoint. We'll be back to display
4035 if (stopped_by_watchpoint
4036 && (target_have_steppable_watchpoint
4037 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4039 /* At this point, we are stopped at an instruction which has
4040 attempted to write to a piece of memory under control of
4041 a watchpoint. The instruction hasn't actually executed
4042 yet. If we were to evaluate the watchpoint expression
4043 now, we would get the old value, and therefore no change
4044 would seem to have occurred.
4046 In order to make watchpoints work `right', we really need
4047 to complete the memory write, and then evaluate the
4048 watchpoint expression. We do this by single-stepping the
4051 It may not be necessary to disable the watchpoint to stop over
4052 it. For example, the PA can (with some kernel cooperation)
4053 single step over a watchpoint without disabling the watchpoint.
4055 It is far more common to need to disable a watchpoint to step
4056 the inferior over it. If we have non-steppable watchpoints,
4057 we must disable the current watchpoint; it's simplest to
4058 disable all watchpoints and breakpoints. */
4061 if (!target_have_steppable_watchpoint
)
4063 remove_breakpoints ();
4064 /* See comment in resume why we need to stop bypassing signals
4065 while breakpoints have been removed. */
4066 target_pass_signals (0, NULL
);
4069 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
4070 target_resume (ecs
->ptid
, hw_step
, GDB_SIGNAL_0
);
4071 waiton_ptid
= ecs
->ptid
;
4072 if (target_have_steppable_watchpoint
)
4073 infwait_state
= infwait_step_watch_state
;
4075 infwait_state
= infwait_nonstep_watch_state
;
4076 prepare_to_wait (ecs
);
4080 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4081 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4082 ecs
->event_thread
->control
.stop_step
= 0;
4083 stop_print_frame
= 1;
4084 stopped_by_random_signal
= 0;
4086 /* Hide inlined functions starting here, unless we just performed stepi or
4087 nexti. After stepi and nexti, always show the innermost frame (not any
4088 inline function call sites). */
4089 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4091 struct address_space
*aspace
=
4092 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4094 /* skip_inline_frames is expensive, so we avoid it if we can
4095 determine that the address is one where functions cannot have
4096 been inlined. This improves performance with inferiors that
4097 load a lot of shared libraries, because the solib event
4098 breakpoint is defined as the address of a function (i.e. not
4099 inline). Note that we have to check the previous PC as well
4100 as the current one to catch cases when we have just
4101 single-stepped off a breakpoint prior to reinstating it.
4102 Note that we're assuming that the code we single-step to is
4103 not inline, but that's not definitive: there's nothing
4104 preventing the event breakpoint function from containing
4105 inlined code, and the single-step ending up there. If the
4106 user had set a breakpoint on that inlined code, the missing
4107 skip_inline_frames call would break things. Fortunately
4108 that's an extremely unlikely scenario. */
4109 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4110 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4111 && ecs
->event_thread
->control
.trap_expected
4112 && pc_at_non_inline_function (aspace
,
4113 ecs
->event_thread
->prev_pc
,
4116 skip_inline_frames (ecs
->ptid
);
4118 /* Re-fetch current thread's frame in case that invalidated
4120 frame
= get_current_frame ();
4121 gdbarch
= get_frame_arch (frame
);
4125 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4126 && ecs
->event_thread
->control
.trap_expected
4127 && gdbarch_single_step_through_delay_p (gdbarch
)
4128 && currently_stepping (ecs
->event_thread
))
4130 /* We're trying to step off a breakpoint. Turns out that we're
4131 also on an instruction that needs to be stepped multiple
4132 times before it's been fully executing. E.g., architectures
4133 with a delay slot. It needs to be stepped twice, once for
4134 the instruction and once for the delay slot. */
4135 int step_through_delay
4136 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4138 if (debug_infrun
&& step_through_delay
)
4139 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4140 if (ecs
->event_thread
->control
.step_range_end
== 0
4141 && step_through_delay
)
4143 /* The user issued a continue when stopped at a breakpoint.
4144 Set up for another trap and get out of here. */
4145 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4149 else if (step_through_delay
)
4151 /* The user issued a step when stopped at a breakpoint.
4152 Maybe we should stop, maybe we should not - the delay
4153 slot *might* correspond to a line of source. In any
4154 case, don't decide that here, just set
4155 ecs->stepping_over_breakpoint, making sure we
4156 single-step again before breakpoints are re-inserted. */
4157 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4161 /* Look at the cause of the stop, and decide what to do.
4162 The alternatives are:
4163 1) stop_stepping and return; to really stop and return to the debugger,
4164 2) keep_going and return to start up again
4165 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
4166 3) set ecs->random_signal to 1, and the decision between 1 and 2
4167 will be made according to the signal handling tables. */
4169 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4173 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4174 stop_print_frame
= 0;
4175 stop_stepping (ecs
);
4179 /* This is originated from start_remote(), start_inferior() and
4180 shared libraries hook functions. */
4181 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4184 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4185 stop_stepping (ecs
);
4189 /* This originates from attach_command(). We need to overwrite
4190 the stop_signal here, because some kernels don't ignore a
4191 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4192 See more comments in inferior.h. On the other hand, if we
4193 get a non-SIGSTOP, report it to the user - assume the backend
4194 will handle the SIGSTOP if it should show up later.
4196 Also consider that the attach is complete when we see a
4197 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4198 target extended-remote report it instead of a SIGSTOP
4199 (e.g. gdbserver). We already rely on SIGTRAP being our
4200 signal, so this is no exception.
4202 Also consider that the attach is complete when we see a
4203 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4204 the target to stop all threads of the inferior, in case the
4205 low level attach operation doesn't stop them implicitly. If
4206 they weren't stopped implicitly, then the stub will report a
4207 GDB_SIGNAL_0, meaning: stopped for no particular reason
4208 other than GDB's request. */
4209 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4210 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4211 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4212 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4214 stop_stepping (ecs
);
4215 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4219 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4220 handles this event. */
4221 ecs
->event_thread
->control
.stop_bpstat
4222 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4223 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4225 /* Following in case break condition called a
4227 stop_print_frame
= 1;
4229 /* This is where we handle "moribund" watchpoints. Unlike
4230 software breakpoints traps, hardware watchpoint traps are
4231 always distinguishable from random traps. If no high-level
4232 watchpoint is associated with the reported stop data address
4233 anymore, then the bpstat does not explain the signal ---
4234 simply make sure to ignore it if `stopped_by_watchpoint' is
4238 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4239 && (bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4241 == BPSTAT_SIGNAL_NO
)
4242 && stopped_by_watchpoint
)
4243 fprintf_unfiltered (gdb_stdlog
,
4244 "infrun: no user watchpoint explains "
4245 "watchpoint SIGTRAP, ignoring\n");
4247 /* NOTE: cagney/2003-03-29: These two checks for a random signal
4248 at one stage in the past included checks for an inferior
4249 function call's call dummy's return breakpoint. The original
4250 comment, that went with the test, read:
4252 ``End of a stack dummy. Some systems (e.g. Sony news) give
4253 another signal besides SIGTRAP, so check here as well as
4256 If someone ever tries to get call dummys on a
4257 non-executable stack to work (where the target would stop
4258 with something like a SIGSEGV), then those tests might need
4259 to be re-instated. Given, however, that the tests were only
4260 enabled when momentary breakpoints were not being used, I
4261 suspect that it won't be the case.
4263 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4264 be necessary for call dummies on a non-executable stack on
4267 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4269 = !((bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4271 != BPSTAT_SIGNAL_NO
)
4272 || stopped_by_watchpoint
4273 || ecs
->event_thread
->control
.trap_expected
4274 || (ecs
->event_thread
->control
.step_range_end
4275 && (ecs
->event_thread
->control
.step_resume_breakpoint
4279 enum bpstat_signal_value sval
;
4281 sval
= bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4282 ecs
->event_thread
->suspend
.stop_signal
);
4283 ecs
->random_signal
= (sval
== BPSTAT_SIGNAL_NO
);
4285 if (sval
== BPSTAT_SIGNAL_HIDE
)
4286 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4289 /* For the program's own signals, act according to
4290 the signal handling tables. */
4292 if (ecs
->random_signal
)
4294 /* Signal not for debugging purposes. */
4296 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
4297 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
4300 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
4301 gdb_signal_to_symbol_string (stop_signal
));
4303 stopped_by_random_signal
= 1;
4305 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4308 target_terminal_ours_for_output ();
4309 print_signal_received_reason
4310 (ecs
->event_thread
->suspend
.stop_signal
);
4312 /* Always stop on signals if we're either just gaining control
4313 of the program, or the user explicitly requested this thread
4314 to remain stopped. */
4315 if (stop_soon
!= NO_STOP_QUIETLY
4316 || ecs
->event_thread
->stop_requested
4318 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4320 stop_stepping (ecs
);
4323 /* If not going to stop, give terminal back
4324 if we took it away. */
4326 target_terminal_inferior ();
4328 /* Clear the signal if it should not be passed. */
4329 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4330 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4332 if (ecs
->event_thread
->prev_pc
== stop_pc
4333 && ecs
->event_thread
->control
.trap_expected
4334 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4336 /* We were just starting a new sequence, attempting to
4337 single-step off of a breakpoint and expecting a SIGTRAP.
4338 Instead this signal arrives. This signal will take us out
4339 of the stepping range so GDB needs to remember to, when
4340 the signal handler returns, resume stepping off that
4342 /* To simplify things, "continue" is forced to use the same
4343 code paths as single-step - set a breakpoint at the
4344 signal return address and then, once hit, step off that
4347 fprintf_unfiltered (gdb_stdlog
,
4348 "infrun: signal arrived while stepping over "
4351 insert_hp_step_resume_breakpoint_at_frame (frame
);
4352 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4353 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4354 ecs
->event_thread
->control
.trap_expected
= 0;
4359 if (ecs
->event_thread
->control
.step_range_end
!= 0
4360 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4361 && pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4362 && frame_id_eq (get_stack_frame_id (frame
),
4363 ecs
->event_thread
->control
.step_stack_frame_id
)
4364 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4366 /* The inferior is about to take a signal that will take it
4367 out of the single step range. Set a breakpoint at the
4368 current PC (which is presumably where the signal handler
4369 will eventually return) and then allow the inferior to
4372 Note that this is only needed for a signal delivered
4373 while in the single-step range. Nested signals aren't a
4374 problem as they eventually all return. */
4376 fprintf_unfiltered (gdb_stdlog
,
4377 "infrun: signal may take us out of "
4378 "single-step range\n");
4380 insert_hp_step_resume_breakpoint_at_frame (frame
);
4381 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4382 ecs
->event_thread
->control
.trap_expected
= 0;
4387 /* Note: step_resume_breakpoint may be non-NULL. This occures
4388 when either there's a nested signal, or when there's a
4389 pending signal enabled just as the signal handler returns
4390 (leaving the inferior at the step-resume-breakpoint without
4391 actually executing it). Either way continue until the
4392 breakpoint is really hit. */
4394 if (!switch_back_to_stepped_thread (ecs
))
4397 fprintf_unfiltered (gdb_stdlog
,
4398 "infrun: random signal, keep going\n");
4405 process_event_stop_test (ecs
);
4408 /* Come here when we've got some debug event / signal we can explain
4409 (IOW, not a random signal), and test whether it should cause a
4410 stop, or whether we should resume the inferior (transparently).
4411 E.g., could be a breakpoint whose condition evaluates false; we
4412 could be still stepping within the line; etc. */
4415 process_event_stop_test (struct execution_control_state
*ecs
)
4417 struct symtab_and_line stop_pc_sal
;
4418 struct frame_info
*frame
;
4419 struct gdbarch
*gdbarch
;
4420 CORE_ADDR jmp_buf_pc
;
4421 struct bpstat_what what
;
4423 /* Handle cases caused by hitting a breakpoint. */
4425 frame
= get_current_frame ();
4426 gdbarch
= get_frame_arch (frame
);
4428 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4430 if (what
.call_dummy
)
4432 stop_stack_dummy
= what
.call_dummy
;
4435 /* If we hit an internal event that triggers symbol changes, the
4436 current frame will be invalidated within bpstat_what (e.g., if we
4437 hit an internal solib event). Re-fetch it. */
4438 frame
= get_current_frame ();
4439 gdbarch
= get_frame_arch (frame
);
4441 switch (what
.main_action
)
4443 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4444 /* If we hit the breakpoint at longjmp while stepping, we
4445 install a momentary breakpoint at the target of the
4449 fprintf_unfiltered (gdb_stdlog
,
4450 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4452 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4454 if (what
.is_longjmp
)
4456 struct value
*arg_value
;
4458 /* If we set the longjmp breakpoint via a SystemTap probe,
4459 then use it to extract the arguments. The destination PC
4460 is the third argument to the probe. */
4461 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4463 jmp_buf_pc
= value_as_address (arg_value
);
4464 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4465 || !gdbarch_get_longjmp_target (gdbarch
,
4466 frame
, &jmp_buf_pc
))
4469 fprintf_unfiltered (gdb_stdlog
,
4470 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4471 "(!gdbarch_get_longjmp_target)\n");
4476 /* Insert a breakpoint at resume address. */
4477 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4480 check_exception_resume (ecs
, frame
);
4484 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4486 struct frame_info
*init_frame
;
4488 /* There are several cases to consider.
4490 1. The initiating frame no longer exists. In this case we
4491 must stop, because the exception or longjmp has gone too
4494 2. The initiating frame exists, and is the same as the
4495 current frame. We stop, because the exception or longjmp
4498 3. The initiating frame exists and is different from the
4499 current frame. This means the exception or longjmp has
4500 been caught beneath the initiating frame, so keep going.
4502 4. longjmp breakpoint has been placed just to protect
4503 against stale dummy frames and user is not interested in
4504 stopping around longjmps. */
4507 fprintf_unfiltered (gdb_stdlog
,
4508 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4510 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4512 delete_exception_resume_breakpoint (ecs
->event_thread
);
4514 if (what
.is_longjmp
)
4516 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
->num
);
4518 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
4526 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4530 struct frame_id current_id
4531 = get_frame_id (get_current_frame ());
4532 if (frame_id_eq (current_id
,
4533 ecs
->event_thread
->initiating_frame
))
4535 /* Case 2. Fall through. */
4545 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
4547 delete_step_resume_breakpoint (ecs
->event_thread
);
4549 ecs
->event_thread
->control
.stop_step
= 1;
4550 print_end_stepping_range_reason ();
4551 stop_stepping (ecs
);
4555 case BPSTAT_WHAT_SINGLE
:
4557 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4558 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4559 /* Still need to check other stuff, at least the case where we
4560 are stepping and step out of the right range. */
4563 case BPSTAT_WHAT_STEP_RESUME
:
4565 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4567 delete_step_resume_breakpoint (ecs
->event_thread
);
4568 if (ecs
->event_thread
->control
.proceed_to_finish
4569 && execution_direction
== EXEC_REVERSE
)
4571 struct thread_info
*tp
= ecs
->event_thread
;
4573 /* We are finishing a function in reverse, and just hit the
4574 step-resume breakpoint at the start address of the
4575 function, and we're almost there -- just need to back up
4576 by one more single-step, which should take us back to the
4578 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4582 fill_in_stop_func (gdbarch
, ecs
);
4583 if (stop_pc
== ecs
->stop_func_start
4584 && execution_direction
== EXEC_REVERSE
)
4586 /* We are stepping over a function call in reverse, and just
4587 hit the step-resume breakpoint at the start address of
4588 the function. Go back to single-stepping, which should
4589 take us back to the function call. */
4590 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4596 case BPSTAT_WHAT_STOP_NOISY
:
4598 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4599 stop_print_frame
= 1;
4601 /* We are about to nuke the step_resume_breakpointt via the
4602 cleanup chain, so no need to worry about it here. */
4604 stop_stepping (ecs
);
4607 case BPSTAT_WHAT_STOP_SILENT
:
4609 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4610 stop_print_frame
= 0;
4612 /* We are about to nuke the step_resume_breakpoin via the
4613 cleanup chain, so no need to worry about it here. */
4615 stop_stepping (ecs
);
4618 case BPSTAT_WHAT_HP_STEP_RESUME
:
4620 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4622 delete_step_resume_breakpoint (ecs
->event_thread
);
4623 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4625 /* Back when the step-resume breakpoint was inserted, we
4626 were trying to single-step off a breakpoint. Go back to
4628 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4629 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4635 case BPSTAT_WHAT_KEEP_CHECKING
:
4639 /* We come here if we hit a breakpoint but should not stop for it.
4640 Possibly we also were stepping and should stop for that. So fall
4641 through and test for stepping. But, if not stepping, do not
4644 /* In all-stop mode, if we're currently stepping but have stopped in
4645 some other thread, we need to switch back to the stepped thread. */
4646 if (switch_back_to_stepped_thread (ecs
))
4649 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4652 fprintf_unfiltered (gdb_stdlog
,
4653 "infrun: step-resume breakpoint is inserted\n");
4655 /* Having a step-resume breakpoint overrides anything
4656 else having to do with stepping commands until
4657 that breakpoint is reached. */
4662 if (ecs
->event_thread
->control
.step_range_end
== 0)
4665 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4666 /* Likewise if we aren't even stepping. */
4671 /* Re-fetch current thread's frame in case the code above caused
4672 the frame cache to be re-initialized, making our FRAME variable
4673 a dangling pointer. */
4674 frame
= get_current_frame ();
4675 gdbarch
= get_frame_arch (frame
);
4676 fill_in_stop_func (gdbarch
, ecs
);
4678 /* If stepping through a line, keep going if still within it.
4680 Note that step_range_end is the address of the first instruction
4681 beyond the step range, and NOT the address of the last instruction
4684 Note also that during reverse execution, we may be stepping
4685 through a function epilogue and therefore must detect when
4686 the current-frame changes in the middle of a line. */
4688 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4689 && (execution_direction
!= EXEC_REVERSE
4690 || frame_id_eq (get_frame_id (frame
),
4691 ecs
->event_thread
->control
.step_frame_id
)))
4695 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4696 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4697 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4699 /* Tentatively re-enable range stepping; `resume' disables it if
4700 necessary (e.g., if we're stepping over a breakpoint or we
4701 have software watchpoints). */
4702 ecs
->event_thread
->control
.may_range_step
= 1;
4704 /* When stepping backward, stop at beginning of line range
4705 (unless it's the function entry point, in which case
4706 keep going back to the call point). */
4707 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4708 && stop_pc
!= ecs
->stop_func_start
4709 && execution_direction
== EXEC_REVERSE
)
4711 ecs
->event_thread
->control
.stop_step
= 1;
4712 print_end_stepping_range_reason ();
4713 stop_stepping (ecs
);
4721 /* We stepped out of the stepping range. */
4723 /* If we are stepping at the source level and entered the runtime
4724 loader dynamic symbol resolution code...
4726 EXEC_FORWARD: we keep on single stepping until we exit the run
4727 time loader code and reach the callee's address.
4729 EXEC_REVERSE: we've already executed the callee (backward), and
4730 the runtime loader code is handled just like any other
4731 undebuggable function call. Now we need only keep stepping
4732 backward through the trampoline code, and that's handled further
4733 down, so there is nothing for us to do here. */
4735 if (execution_direction
!= EXEC_REVERSE
4736 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4737 && in_solib_dynsym_resolve_code (stop_pc
))
4739 CORE_ADDR pc_after_resolver
=
4740 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4743 fprintf_unfiltered (gdb_stdlog
,
4744 "infrun: stepped into dynsym resolve code\n");
4746 if (pc_after_resolver
)
4748 /* Set up a step-resume breakpoint at the address
4749 indicated by SKIP_SOLIB_RESOLVER. */
4750 struct symtab_and_line sr_sal
;
4753 sr_sal
.pc
= pc_after_resolver
;
4754 sr_sal
.pspace
= get_frame_program_space (frame
);
4756 insert_step_resume_breakpoint_at_sal (gdbarch
,
4757 sr_sal
, null_frame_id
);
4764 if (ecs
->event_thread
->control
.step_range_end
!= 1
4765 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4766 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4767 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
4770 fprintf_unfiltered (gdb_stdlog
,
4771 "infrun: stepped into signal trampoline\n");
4772 /* The inferior, while doing a "step" or "next", has ended up in
4773 a signal trampoline (either by a signal being delivered or by
4774 the signal handler returning). Just single-step until the
4775 inferior leaves the trampoline (either by calling the handler
4781 /* If we're in the return path from a shared library trampoline,
4782 we want to proceed through the trampoline when stepping. */
4783 /* macro/2012-04-25: This needs to come before the subroutine
4784 call check below as on some targets return trampolines look
4785 like subroutine calls (MIPS16 return thunks). */
4786 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4787 stop_pc
, ecs
->stop_func_name
)
4788 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
4790 /* Determine where this trampoline returns. */
4791 CORE_ADDR real_stop_pc
;
4793 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4796 fprintf_unfiltered (gdb_stdlog
,
4797 "infrun: stepped into solib return tramp\n");
4799 /* Only proceed through if we know where it's going. */
4802 /* And put the step-breakpoint there and go until there. */
4803 struct symtab_and_line sr_sal
;
4805 init_sal (&sr_sal
); /* initialize to zeroes */
4806 sr_sal
.pc
= real_stop_pc
;
4807 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4808 sr_sal
.pspace
= get_frame_program_space (frame
);
4810 /* Do not specify what the fp should be when we stop since
4811 on some machines the prologue is where the new fp value
4813 insert_step_resume_breakpoint_at_sal (gdbarch
,
4814 sr_sal
, null_frame_id
);
4816 /* Restart without fiddling with the step ranges or
4823 /* Check for subroutine calls. The check for the current frame
4824 equalling the step ID is not necessary - the check of the
4825 previous frame's ID is sufficient - but it is a common case and
4826 cheaper than checking the previous frame's ID.
4828 NOTE: frame_id_eq will never report two invalid frame IDs as
4829 being equal, so to get into this block, both the current and
4830 previous frame must have valid frame IDs. */
4831 /* The outer_frame_id check is a heuristic to detect stepping
4832 through startup code. If we step over an instruction which
4833 sets the stack pointer from an invalid value to a valid value,
4834 we may detect that as a subroutine call from the mythical
4835 "outermost" function. This could be fixed by marking
4836 outermost frames as !stack_p,code_p,special_p. Then the
4837 initial outermost frame, before sp was valid, would
4838 have code_addr == &_start. See the comment in frame_id_eq
4840 if (!frame_id_eq (get_stack_frame_id (frame
),
4841 ecs
->event_thread
->control
.step_stack_frame_id
)
4842 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4843 ecs
->event_thread
->control
.step_stack_frame_id
)
4844 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
4846 || step_start_function
!= find_pc_function (stop_pc
))))
4848 CORE_ADDR real_stop_pc
;
4851 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
4853 if ((ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
4854 || ((ecs
->event_thread
->control
.step_range_end
== 1)
4855 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
4856 ecs
->stop_func_start
)))
4858 /* I presume that step_over_calls is only 0 when we're
4859 supposed to be stepping at the assembly language level
4860 ("stepi"). Just stop. */
4861 /* Also, maybe we just did a "nexti" inside a prolog, so we
4862 thought it was a subroutine call but it was not. Stop as
4864 /* And this works the same backward as frontward. MVS */
4865 ecs
->event_thread
->control
.stop_step
= 1;
4866 print_end_stepping_range_reason ();
4867 stop_stepping (ecs
);
4871 /* Reverse stepping through solib trampolines. */
4873 if (execution_direction
== EXEC_REVERSE
4874 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
4875 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4876 || (ecs
->stop_func_start
== 0
4877 && in_solib_dynsym_resolve_code (stop_pc
))))
4879 /* Any solib trampoline code can be handled in reverse
4880 by simply continuing to single-step. We have already
4881 executed the solib function (backwards), and a few
4882 steps will take us back through the trampoline to the
4888 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4890 /* We're doing a "next".
4892 Normal (forward) execution: set a breakpoint at the
4893 callee's return address (the address at which the caller
4896 Reverse (backward) execution. set the step-resume
4897 breakpoint at the start of the function that we just
4898 stepped into (backwards), and continue to there. When we
4899 get there, we'll need to single-step back to the caller. */
4901 if (execution_direction
== EXEC_REVERSE
)
4903 /* If we're already at the start of the function, we've either
4904 just stepped backward into a single instruction function,
4905 or stepped back out of a signal handler to the first instruction
4906 of the function. Just keep going, which will single-step back
4908 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
4910 struct symtab_and_line sr_sal
;
4912 /* Normal function call return (static or dynamic). */
4914 sr_sal
.pc
= ecs
->stop_func_start
;
4915 sr_sal
.pspace
= get_frame_program_space (frame
);
4916 insert_step_resume_breakpoint_at_sal (gdbarch
,
4917 sr_sal
, null_frame_id
);
4921 insert_step_resume_breakpoint_at_caller (frame
);
4927 /* If we are in a function call trampoline (a stub between the
4928 calling routine and the real function), locate the real
4929 function. That's what tells us (a) whether we want to step
4930 into it at all, and (b) what prologue we want to run to the
4931 end of, if we do step into it. */
4932 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
4933 if (real_stop_pc
== 0)
4934 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4935 if (real_stop_pc
!= 0)
4936 ecs
->stop_func_start
= real_stop_pc
;
4938 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
4940 struct symtab_and_line sr_sal
;
4943 sr_sal
.pc
= ecs
->stop_func_start
;
4944 sr_sal
.pspace
= get_frame_program_space (frame
);
4946 insert_step_resume_breakpoint_at_sal (gdbarch
,
4947 sr_sal
, null_frame_id
);
4952 /* If we have line number information for the function we are
4953 thinking of stepping into and the function isn't on the skip
4956 If there are several symtabs at that PC (e.g. with include
4957 files), just want to know whether *any* of them have line
4958 numbers. find_pc_line handles this. */
4960 struct symtab_and_line tmp_sal
;
4962 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4963 if (tmp_sal
.line
!= 0
4964 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
4967 if (execution_direction
== EXEC_REVERSE
)
4968 handle_step_into_function_backward (gdbarch
, ecs
);
4970 handle_step_into_function (gdbarch
, ecs
);
4975 /* If we have no line number and the step-stop-if-no-debug is
4976 set, we stop the step so that the user has a chance to switch
4977 in assembly mode. */
4978 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4979 && step_stop_if_no_debug
)
4981 ecs
->event_thread
->control
.stop_step
= 1;
4982 print_end_stepping_range_reason ();
4983 stop_stepping (ecs
);
4987 if (execution_direction
== EXEC_REVERSE
)
4989 /* If we're already at the start of the function, we've either just
4990 stepped backward into a single instruction function without line
4991 number info, or stepped back out of a signal handler to the first
4992 instruction of the function without line number info. Just keep
4993 going, which will single-step back to the caller. */
4994 if (ecs
->stop_func_start
!= stop_pc
)
4996 /* Set a breakpoint at callee's start address.
4997 From there we can step once and be back in the caller. */
4998 struct symtab_and_line sr_sal
;
5001 sr_sal
.pc
= ecs
->stop_func_start
;
5002 sr_sal
.pspace
= get_frame_program_space (frame
);
5003 insert_step_resume_breakpoint_at_sal (gdbarch
,
5004 sr_sal
, null_frame_id
);
5008 /* Set a breakpoint at callee's return address (the address
5009 at which the caller will resume). */
5010 insert_step_resume_breakpoint_at_caller (frame
);
5016 /* Reverse stepping through solib trampolines. */
5018 if (execution_direction
== EXEC_REVERSE
5019 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5021 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5022 || (ecs
->stop_func_start
== 0
5023 && in_solib_dynsym_resolve_code (stop_pc
)))
5025 /* Any solib trampoline code can be handled in reverse
5026 by simply continuing to single-step. We have already
5027 executed the solib function (backwards), and a few
5028 steps will take us back through the trampoline to the
5033 else if (in_solib_dynsym_resolve_code (stop_pc
))
5035 /* Stepped backward into the solib dynsym resolver.
5036 Set a breakpoint at its start and continue, then
5037 one more step will take us out. */
5038 struct symtab_and_line sr_sal
;
5041 sr_sal
.pc
= ecs
->stop_func_start
;
5042 sr_sal
.pspace
= get_frame_program_space (frame
);
5043 insert_step_resume_breakpoint_at_sal (gdbarch
,
5044 sr_sal
, null_frame_id
);
5050 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5052 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5053 the trampoline processing logic, however, there are some trampolines
5054 that have no names, so we should do trampoline handling first. */
5055 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5056 && ecs
->stop_func_name
== NULL
5057 && stop_pc_sal
.line
== 0)
5060 fprintf_unfiltered (gdb_stdlog
,
5061 "infrun: stepped into undebuggable function\n");
5063 /* The inferior just stepped into, or returned to, an
5064 undebuggable function (where there is no debugging information
5065 and no line number corresponding to the address where the
5066 inferior stopped). Since we want to skip this kind of code,
5067 we keep going until the inferior returns from this
5068 function - unless the user has asked us not to (via
5069 set step-mode) or we no longer know how to get back
5070 to the call site. */
5071 if (step_stop_if_no_debug
5072 || !frame_id_p (frame_unwind_caller_id (frame
)))
5074 /* If we have no line number and the step-stop-if-no-debug
5075 is set, we stop the step so that the user has a chance to
5076 switch in assembly mode. */
5077 ecs
->event_thread
->control
.stop_step
= 1;
5078 print_end_stepping_range_reason ();
5079 stop_stepping (ecs
);
5084 /* Set a breakpoint at callee's return address (the address
5085 at which the caller will resume). */
5086 insert_step_resume_breakpoint_at_caller (frame
);
5092 if (ecs
->event_thread
->control
.step_range_end
== 1)
5094 /* It is stepi or nexti. We always want to stop stepping after
5097 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5098 ecs
->event_thread
->control
.stop_step
= 1;
5099 print_end_stepping_range_reason ();
5100 stop_stepping (ecs
);
5104 if (stop_pc_sal
.line
== 0)
5106 /* We have no line number information. That means to stop
5107 stepping (does this always happen right after one instruction,
5108 when we do "s" in a function with no line numbers,
5109 or can this happen as a result of a return or longjmp?). */
5111 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5112 ecs
->event_thread
->control
.stop_step
= 1;
5113 print_end_stepping_range_reason ();
5114 stop_stepping (ecs
);
5118 /* Look for "calls" to inlined functions, part one. If the inline
5119 frame machinery detected some skipped call sites, we have entered
5120 a new inline function. */
5122 if (frame_id_eq (get_frame_id (get_current_frame ()),
5123 ecs
->event_thread
->control
.step_frame_id
)
5124 && inline_skipped_frames (ecs
->ptid
))
5126 struct symtab_and_line call_sal
;
5129 fprintf_unfiltered (gdb_stdlog
,
5130 "infrun: stepped into inlined function\n");
5132 find_frame_sal (get_current_frame (), &call_sal
);
5134 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5136 /* For "step", we're going to stop. But if the call site
5137 for this inlined function is on the same source line as
5138 we were previously stepping, go down into the function
5139 first. Otherwise stop at the call site. */
5141 if (call_sal
.line
== ecs
->event_thread
->current_line
5142 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5143 step_into_inline_frame (ecs
->ptid
);
5145 ecs
->event_thread
->control
.stop_step
= 1;
5146 print_end_stepping_range_reason ();
5147 stop_stepping (ecs
);
5152 /* For "next", we should stop at the call site if it is on a
5153 different source line. Otherwise continue through the
5154 inlined function. */
5155 if (call_sal
.line
== ecs
->event_thread
->current_line
5156 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5160 ecs
->event_thread
->control
.stop_step
= 1;
5161 print_end_stepping_range_reason ();
5162 stop_stepping (ecs
);
5168 /* Look for "calls" to inlined functions, part two. If we are still
5169 in the same real function we were stepping through, but we have
5170 to go further up to find the exact frame ID, we are stepping
5171 through a more inlined call beyond its call site. */
5173 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5174 && !frame_id_eq (get_frame_id (get_current_frame ()),
5175 ecs
->event_thread
->control
.step_frame_id
)
5176 && stepped_in_from (get_current_frame (),
5177 ecs
->event_thread
->control
.step_frame_id
))
5180 fprintf_unfiltered (gdb_stdlog
,
5181 "infrun: stepping through inlined function\n");
5183 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5187 ecs
->event_thread
->control
.stop_step
= 1;
5188 print_end_stepping_range_reason ();
5189 stop_stepping (ecs
);
5194 if ((stop_pc
== stop_pc_sal
.pc
)
5195 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5196 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5198 /* We are at the start of a different line. So stop. Note that
5199 we don't stop if we step into the middle of a different line.
5200 That is said to make things like for (;;) statements work
5203 fprintf_unfiltered (gdb_stdlog
,
5204 "infrun: stepped to a different line\n");
5205 ecs
->event_thread
->control
.stop_step
= 1;
5206 print_end_stepping_range_reason ();
5207 stop_stepping (ecs
);
5211 /* We aren't done stepping.
5213 Optimize by setting the stepping range to the line.
5214 (We might not be in the original line, but if we entered a
5215 new line in mid-statement, we continue stepping. This makes
5216 things like for(;;) statements work better.) */
5218 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5219 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5220 ecs
->event_thread
->control
.may_range_step
= 1;
5221 set_step_info (frame
, stop_pc_sal
);
5224 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5228 /* In all-stop mode, if we're currently stepping but have stopped in
5229 some other thread, we may need to switch back to the stepped
5230 thread. Returns true we set the inferior running, false if we left
5231 it stopped (and the event needs further processing). */
5234 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
5238 struct thread_info
*tp
;
5240 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
5244 /* However, if the current thread is blocked on some internal
5245 breakpoint, and we simply need to step over that breakpoint
5246 to get it going again, do that first. */
5247 if ((ecs
->event_thread
->control
.trap_expected
5248 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5249 || ecs
->event_thread
->stepping_over_breakpoint
)
5255 /* If the stepping thread exited, then don't try to switch
5256 back and resume it, which could fail in several different
5257 ways depending on the target. Instead, just keep going.
5259 We can find a stepping dead thread in the thread list in
5262 - The target supports thread exit events, and when the
5263 target tries to delete the thread from the thread list,
5264 inferior_ptid pointed at the exiting thread. In such
5265 case, calling delete_thread does not really remove the
5266 thread from the list; instead, the thread is left listed,
5267 with 'exited' state.
5269 - The target's debug interface does not support thread
5270 exit events, and so we have no idea whatsoever if the
5271 previously stepping thread is still alive. For that
5272 reason, we need to synchronously query the target
5274 if (is_exited (tp
->ptid
)
5275 || !target_thread_alive (tp
->ptid
))
5278 fprintf_unfiltered (gdb_stdlog
,
5279 "infrun: not switching back to "
5280 "stepped thread, it has vanished\n");
5282 delete_thread (tp
->ptid
);
5287 /* Otherwise, we no longer expect a trap in the current thread.
5288 Clear the trap_expected flag before switching back -- this is
5289 what keep_going would do as well, if we called it. */
5290 ecs
->event_thread
->control
.trap_expected
= 0;
5293 fprintf_unfiltered (gdb_stdlog
,
5294 "infrun: switching back to stepped thread\n");
5296 ecs
->event_thread
= tp
;
5297 ecs
->ptid
= tp
->ptid
;
5298 context_switch (ecs
->ptid
);
5306 /* Is thread TP in the middle of single-stepping? */
5309 currently_stepping (struct thread_info
*tp
)
5311 return ((tp
->control
.step_range_end
5312 && tp
->control
.step_resume_breakpoint
== NULL
)
5313 || tp
->control
.trap_expected
5314 || bpstat_should_step ());
5317 /* Returns true if any thread *but* the one passed in "data" is in the
5318 middle of stepping or of handling a "next". */
5321 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
5326 return (tp
->control
.step_range_end
5327 || tp
->control
.trap_expected
);
5330 /* Inferior has stepped into a subroutine call with source code that
5331 we should not step over. Do step to the first line of code in
5335 handle_step_into_function (struct gdbarch
*gdbarch
,
5336 struct execution_control_state
*ecs
)
5339 struct symtab_and_line stop_func_sal
, sr_sal
;
5341 fill_in_stop_func (gdbarch
, ecs
);
5343 s
= find_pc_symtab (stop_pc
);
5344 if (s
&& s
->language
!= language_asm
)
5345 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5346 ecs
->stop_func_start
);
5348 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5349 /* Use the step_resume_break to step until the end of the prologue,
5350 even if that involves jumps (as it seems to on the vax under
5352 /* If the prologue ends in the middle of a source line, continue to
5353 the end of that source line (if it is still within the function).
5354 Otherwise, just go to end of prologue. */
5355 if (stop_func_sal
.end
5356 && stop_func_sal
.pc
!= ecs
->stop_func_start
5357 && stop_func_sal
.end
< ecs
->stop_func_end
)
5358 ecs
->stop_func_start
= stop_func_sal
.end
;
5360 /* Architectures which require breakpoint adjustment might not be able
5361 to place a breakpoint at the computed address. If so, the test
5362 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5363 ecs->stop_func_start to an address at which a breakpoint may be
5364 legitimately placed.
5366 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5367 made, GDB will enter an infinite loop when stepping through
5368 optimized code consisting of VLIW instructions which contain
5369 subinstructions corresponding to different source lines. On
5370 FR-V, it's not permitted to place a breakpoint on any but the
5371 first subinstruction of a VLIW instruction. When a breakpoint is
5372 set, GDB will adjust the breakpoint address to the beginning of
5373 the VLIW instruction. Thus, we need to make the corresponding
5374 adjustment here when computing the stop address. */
5376 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5378 ecs
->stop_func_start
5379 = gdbarch_adjust_breakpoint_address (gdbarch
,
5380 ecs
->stop_func_start
);
5383 if (ecs
->stop_func_start
== stop_pc
)
5385 /* We are already there: stop now. */
5386 ecs
->event_thread
->control
.stop_step
= 1;
5387 print_end_stepping_range_reason ();
5388 stop_stepping (ecs
);
5393 /* Put the step-breakpoint there and go until there. */
5394 init_sal (&sr_sal
); /* initialize to zeroes */
5395 sr_sal
.pc
= ecs
->stop_func_start
;
5396 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5397 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5399 /* Do not specify what the fp should be when we stop since on
5400 some machines the prologue is where the new fp value is
5402 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5404 /* And make sure stepping stops right away then. */
5405 ecs
->event_thread
->control
.step_range_end
5406 = ecs
->event_thread
->control
.step_range_start
;
5411 /* Inferior has stepped backward into a subroutine call with source
5412 code that we should not step over. Do step to the beginning of the
5413 last line of code in it. */
5416 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5417 struct execution_control_state
*ecs
)
5420 struct symtab_and_line stop_func_sal
;
5422 fill_in_stop_func (gdbarch
, ecs
);
5424 s
= find_pc_symtab (stop_pc
);
5425 if (s
&& s
->language
!= language_asm
)
5426 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5427 ecs
->stop_func_start
);
5429 stop_func_sal
= find_pc_line (stop_pc
, 0);
5431 /* OK, we're just going to keep stepping here. */
5432 if (stop_func_sal
.pc
== stop_pc
)
5434 /* We're there already. Just stop stepping now. */
5435 ecs
->event_thread
->control
.stop_step
= 1;
5436 print_end_stepping_range_reason ();
5437 stop_stepping (ecs
);
5441 /* Else just reset the step range and keep going.
5442 No step-resume breakpoint, they don't work for
5443 epilogues, which can have multiple entry paths. */
5444 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5445 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5451 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5452 This is used to both functions and to skip over code. */
5455 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5456 struct symtab_and_line sr_sal
,
5457 struct frame_id sr_id
,
5458 enum bptype sr_type
)
5460 /* There should never be more than one step-resume or longjmp-resume
5461 breakpoint per thread, so we should never be setting a new
5462 step_resume_breakpoint when one is already active. */
5463 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5464 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5467 fprintf_unfiltered (gdb_stdlog
,
5468 "infrun: inserting step-resume breakpoint at %s\n",
5469 paddress (gdbarch
, sr_sal
.pc
));
5471 inferior_thread ()->control
.step_resume_breakpoint
5472 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5476 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5477 struct symtab_and_line sr_sal
,
5478 struct frame_id sr_id
)
5480 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5485 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5486 This is used to skip a potential signal handler.
5488 This is called with the interrupted function's frame. The signal
5489 handler, when it returns, will resume the interrupted function at
5493 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5495 struct symtab_and_line sr_sal
;
5496 struct gdbarch
*gdbarch
;
5498 gdb_assert (return_frame
!= NULL
);
5499 init_sal (&sr_sal
); /* initialize to zeros */
5501 gdbarch
= get_frame_arch (return_frame
);
5502 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5503 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5504 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5506 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5507 get_stack_frame_id (return_frame
),
5511 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5512 is used to skip a function after stepping into it (for "next" or if
5513 the called function has no debugging information).
5515 The current function has almost always been reached by single
5516 stepping a call or return instruction. NEXT_FRAME belongs to the
5517 current function, and the breakpoint will be set at the caller's
5520 This is a separate function rather than reusing
5521 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5522 get_prev_frame, which may stop prematurely (see the implementation
5523 of frame_unwind_caller_id for an example). */
5526 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5528 struct symtab_and_line sr_sal
;
5529 struct gdbarch
*gdbarch
;
5531 /* We shouldn't have gotten here if we don't know where the call site
5533 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5535 init_sal (&sr_sal
); /* initialize to zeros */
5537 gdbarch
= frame_unwind_caller_arch (next_frame
);
5538 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5539 frame_unwind_caller_pc (next_frame
));
5540 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5541 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5543 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5544 frame_unwind_caller_id (next_frame
));
5547 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5548 new breakpoint at the target of a jmp_buf. The handling of
5549 longjmp-resume uses the same mechanisms used for handling
5550 "step-resume" breakpoints. */
5553 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5555 /* There should never be more than one longjmp-resume breakpoint per
5556 thread, so we should never be setting a new
5557 longjmp_resume_breakpoint when one is already active. */
5558 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
5561 fprintf_unfiltered (gdb_stdlog
,
5562 "infrun: inserting longjmp-resume breakpoint at %s\n",
5563 paddress (gdbarch
, pc
));
5565 inferior_thread ()->control
.exception_resume_breakpoint
=
5566 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5569 /* Insert an exception resume breakpoint. TP is the thread throwing
5570 the exception. The block B is the block of the unwinder debug hook
5571 function. FRAME is the frame corresponding to the call to this
5572 function. SYM is the symbol of the function argument holding the
5573 target PC of the exception. */
5576 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5578 struct frame_info
*frame
,
5581 volatile struct gdb_exception e
;
5583 /* We want to ignore errors here. */
5584 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5586 struct symbol
*vsym
;
5587 struct value
*value
;
5589 struct breakpoint
*bp
;
5591 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5592 value
= read_var_value (vsym
, frame
);
5593 /* If the value was optimized out, revert to the old behavior. */
5594 if (! value_optimized_out (value
))
5596 handler
= value_as_address (value
);
5599 fprintf_unfiltered (gdb_stdlog
,
5600 "infrun: exception resume at %lx\n",
5601 (unsigned long) handler
);
5603 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5604 handler
, bp_exception_resume
);
5606 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5609 bp
->thread
= tp
->num
;
5610 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5615 /* A helper for check_exception_resume that sets an
5616 exception-breakpoint based on a SystemTap probe. */
5619 insert_exception_resume_from_probe (struct thread_info
*tp
,
5620 const struct probe
*probe
,
5621 struct frame_info
*frame
)
5623 struct value
*arg_value
;
5625 struct breakpoint
*bp
;
5627 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
5631 handler
= value_as_address (arg_value
);
5634 fprintf_unfiltered (gdb_stdlog
,
5635 "infrun: exception resume at %s\n",
5636 paddress (get_objfile_arch (probe
->objfile
),
5639 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5640 handler
, bp_exception_resume
);
5641 bp
->thread
= tp
->num
;
5642 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5645 /* This is called when an exception has been intercepted. Check to
5646 see whether the exception's destination is of interest, and if so,
5647 set an exception resume breakpoint there. */
5650 check_exception_resume (struct execution_control_state
*ecs
,
5651 struct frame_info
*frame
)
5653 volatile struct gdb_exception e
;
5654 const struct probe
*probe
;
5655 struct symbol
*func
;
5657 /* First see if this exception unwinding breakpoint was set via a
5658 SystemTap probe point. If so, the probe has two arguments: the
5659 CFA and the HANDLER. We ignore the CFA, extract the handler, and
5660 set a breakpoint there. */
5661 probe
= find_probe_by_pc (get_frame_pc (frame
));
5664 insert_exception_resume_from_probe (ecs
->event_thread
, probe
, frame
);
5668 func
= get_frame_function (frame
);
5672 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5675 struct block_iterator iter
;
5679 /* The exception breakpoint is a thread-specific breakpoint on
5680 the unwinder's debug hook, declared as:
5682 void _Unwind_DebugHook (void *cfa, void *handler);
5684 The CFA argument indicates the frame to which control is
5685 about to be transferred. HANDLER is the destination PC.
5687 We ignore the CFA and set a temporary breakpoint at HANDLER.
5688 This is not extremely efficient but it avoids issues in gdb
5689 with computing the DWARF CFA, and it also works even in weird
5690 cases such as throwing an exception from inside a signal
5693 b
= SYMBOL_BLOCK_VALUE (func
);
5694 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
5696 if (!SYMBOL_IS_ARGUMENT (sym
))
5703 insert_exception_resume_breakpoint (ecs
->event_thread
,
5712 stop_stepping (struct execution_control_state
*ecs
)
5715 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
5717 /* Let callers know we don't want to wait for the inferior anymore. */
5718 ecs
->wait_some_more
= 0;
5721 /* Called when we should continue running the inferior, because the
5722 current event doesn't cause a user visible stop. This does the
5723 resuming part; waiting for the next event is done elsewhere. */
5726 keep_going (struct execution_control_state
*ecs
)
5728 /* Make sure normal_stop is called if we get a QUIT handled before
5730 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
5732 /* Save the pc before execution, to compare with pc after stop. */
5733 ecs
->event_thread
->prev_pc
5734 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5736 if (ecs
->event_thread
->control
.trap_expected
5737 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5739 /* We haven't yet gotten our trap, and either: intercepted a
5740 non-signal event (e.g., a fork); or took a signal which we
5741 are supposed to pass through to the inferior. Simply
5743 discard_cleanups (old_cleanups
);
5744 resume (currently_stepping (ecs
->event_thread
),
5745 ecs
->event_thread
->suspend
.stop_signal
);
5749 /* Either the trap was not expected, but we are continuing
5750 anyway (if we got a signal, the user asked it be passed to
5753 We got our expected trap, but decided we should resume from
5756 We're going to run this baby now!
5758 Note that insert_breakpoints won't try to re-insert
5759 already inserted breakpoints. Therefore, we don't
5760 care if breakpoints were already inserted, or not. */
5762 if (ecs
->event_thread
->stepping_over_breakpoint
)
5764 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
5766 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
5768 /* Since we can't do a displaced step, we have to remove
5769 the breakpoint while we step it. To keep things
5770 simple, we remove them all. */
5771 remove_breakpoints ();
5776 volatile struct gdb_exception e
;
5778 /* Stop stepping if inserting breakpoints fails. */
5779 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5781 insert_breakpoints ();
5785 exception_print (gdb_stderr
, e
);
5786 stop_stepping (ecs
);
5791 ecs
->event_thread
->control
.trap_expected
5792 = ecs
->event_thread
->stepping_over_breakpoint
;
5794 /* Do not deliver GDB_SIGNAL_TRAP (except when the user
5795 explicitly specifies that such a signal should be delivered
5796 to the target program). Typically, that would occur when a
5797 user is debugging a target monitor on a simulator: the target
5798 monitor sets a breakpoint; the simulator encounters this
5799 breakpoint and halts the simulation handing control to GDB;
5800 GDB, noting that the stop address doesn't map to any known
5801 breakpoint, returns control back to the simulator; the
5802 simulator then delivers the hardware equivalent of a
5803 GDB_SIGNAL_TRAP to the program being debugged. */
5804 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5805 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5806 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5808 discard_cleanups (old_cleanups
);
5809 resume (currently_stepping (ecs
->event_thread
),
5810 ecs
->event_thread
->suspend
.stop_signal
);
5813 prepare_to_wait (ecs
);
5816 /* This function normally comes after a resume, before
5817 handle_inferior_event exits. It takes care of any last bits of
5818 housekeeping, and sets the all-important wait_some_more flag. */
5821 prepare_to_wait (struct execution_control_state
*ecs
)
5824 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
5826 /* This is the old end of the while loop. Let everybody know we
5827 want to wait for the inferior some more and get called again
5829 ecs
->wait_some_more
= 1;
5832 /* Several print_*_reason functions to print why the inferior has stopped.
5833 We always print something when the inferior exits, or receives a signal.
5834 The rest of the cases are dealt with later on in normal_stop and
5835 print_it_typical. Ideally there should be a call to one of these
5836 print_*_reason functions functions from handle_inferior_event each time
5837 stop_stepping is called. */
5839 /* Print why the inferior has stopped.
5840 We are done with a step/next/si/ni command, print why the inferior has
5841 stopped. For now print nothing. Print a message only if not in the middle
5842 of doing a "step n" operation for n > 1. */
5845 print_end_stepping_range_reason (void)
5847 if ((!inferior_thread ()->step_multi
5848 || !inferior_thread ()->control
.stop_step
)
5849 && ui_out_is_mi_like_p (current_uiout
))
5850 ui_out_field_string (current_uiout
, "reason",
5851 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
5854 /* The inferior was terminated by a signal, print why it stopped. */
5857 print_signal_exited_reason (enum gdb_signal siggnal
)
5859 struct ui_out
*uiout
= current_uiout
;
5861 annotate_signalled ();
5862 if (ui_out_is_mi_like_p (uiout
))
5864 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
5865 ui_out_text (uiout
, "\nProgram terminated with signal ");
5866 annotate_signal_name ();
5867 ui_out_field_string (uiout
, "signal-name",
5868 gdb_signal_to_name (siggnal
));
5869 annotate_signal_name_end ();
5870 ui_out_text (uiout
, ", ");
5871 annotate_signal_string ();
5872 ui_out_field_string (uiout
, "signal-meaning",
5873 gdb_signal_to_string (siggnal
));
5874 annotate_signal_string_end ();
5875 ui_out_text (uiout
, ".\n");
5876 ui_out_text (uiout
, "The program no longer exists.\n");
5879 /* The inferior program is finished, print why it stopped. */
5882 print_exited_reason (int exitstatus
)
5884 struct inferior
*inf
= current_inferior ();
5885 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
5886 struct ui_out
*uiout
= current_uiout
;
5888 annotate_exited (exitstatus
);
5891 if (ui_out_is_mi_like_p (uiout
))
5892 ui_out_field_string (uiout
, "reason",
5893 async_reason_lookup (EXEC_ASYNC_EXITED
));
5894 ui_out_text (uiout
, "[Inferior ");
5895 ui_out_text (uiout
, plongest (inf
->num
));
5896 ui_out_text (uiout
, " (");
5897 ui_out_text (uiout
, pidstr
);
5898 ui_out_text (uiout
, ") exited with code ");
5899 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
5900 ui_out_text (uiout
, "]\n");
5904 if (ui_out_is_mi_like_p (uiout
))
5906 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
5907 ui_out_text (uiout
, "[Inferior ");
5908 ui_out_text (uiout
, plongest (inf
->num
));
5909 ui_out_text (uiout
, " (");
5910 ui_out_text (uiout
, pidstr
);
5911 ui_out_text (uiout
, ") exited normally]\n");
5913 /* Support the --return-child-result option. */
5914 return_child_result_value
= exitstatus
;
5917 /* Signal received, print why the inferior has stopped. The signal table
5918 tells us to print about it. */
5921 print_signal_received_reason (enum gdb_signal siggnal
)
5923 struct ui_out
*uiout
= current_uiout
;
5927 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
5929 struct thread_info
*t
= inferior_thread ();
5931 ui_out_text (uiout
, "\n[");
5932 ui_out_field_string (uiout
, "thread-name",
5933 target_pid_to_str (t
->ptid
));
5934 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
5935 ui_out_text (uiout
, " stopped");
5939 ui_out_text (uiout
, "\nProgram received signal ");
5940 annotate_signal_name ();
5941 if (ui_out_is_mi_like_p (uiout
))
5943 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
5944 ui_out_field_string (uiout
, "signal-name",
5945 gdb_signal_to_name (siggnal
));
5946 annotate_signal_name_end ();
5947 ui_out_text (uiout
, ", ");
5948 annotate_signal_string ();
5949 ui_out_field_string (uiout
, "signal-meaning",
5950 gdb_signal_to_string (siggnal
));
5951 annotate_signal_string_end ();
5953 ui_out_text (uiout
, ".\n");
5956 /* Reverse execution: target ran out of history info, print why the inferior
5960 print_no_history_reason (void)
5962 ui_out_text (current_uiout
, "\nNo more reverse-execution history.\n");
5965 /* Here to return control to GDB when the inferior stops for real.
5966 Print appropriate messages, remove breakpoints, give terminal our modes.
5968 STOP_PRINT_FRAME nonzero means print the executing frame
5969 (pc, function, args, file, line number and line text).
5970 BREAKPOINTS_FAILED nonzero means stop was due to error
5971 attempting to insert breakpoints. */
5976 struct target_waitstatus last
;
5978 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
5980 get_last_target_status (&last_ptid
, &last
);
5982 /* If an exception is thrown from this point on, make sure to
5983 propagate GDB's knowledge of the executing state to the
5984 frontend/user running state. A QUIT is an easy exception to see
5985 here, so do this before any filtered output. */
5987 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
5988 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5989 && last
.kind
!= TARGET_WAITKIND_EXITED
5990 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5991 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
5993 /* In non-stop mode, we don't want GDB to switch threads behind the
5994 user's back, to avoid races where the user is typing a command to
5995 apply to thread x, but GDB switches to thread y before the user
5996 finishes entering the command. */
5998 /* As with the notification of thread events, we want to delay
5999 notifying the user that we've switched thread context until
6000 the inferior actually stops.
6002 There's no point in saying anything if the inferior has exited.
6003 Note that SIGNALLED here means "exited with a signal", not
6004 "received a signal". */
6006 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
6007 && target_has_execution
6008 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6009 && last
.kind
!= TARGET_WAITKIND_EXITED
6010 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6012 target_terminal_ours_for_output ();
6013 printf_filtered (_("[Switching to %s]\n"),
6014 target_pid_to_str (inferior_ptid
));
6015 annotate_thread_changed ();
6016 previous_inferior_ptid
= inferior_ptid
;
6019 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
6021 gdb_assert (sync_execution
|| !target_can_async_p ());
6023 target_terminal_ours_for_output ();
6024 printf_filtered (_("No unwaited-for children left.\n"));
6027 if (!breakpoints_always_inserted_mode () && target_has_execution
)
6029 if (remove_breakpoints ())
6031 target_terminal_ours_for_output ();
6032 printf_filtered (_("Cannot remove breakpoints because "
6033 "program is no longer writable.\nFurther "
6034 "execution is probably impossible.\n"));
6038 /* If an auto-display called a function and that got a signal,
6039 delete that auto-display to avoid an infinite recursion. */
6041 if (stopped_by_random_signal
)
6042 disable_current_display ();
6044 /* Don't print a message if in the middle of doing a "step n"
6045 operation for n > 1 */
6046 if (target_has_execution
6047 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6048 && last
.kind
!= TARGET_WAITKIND_EXITED
6049 && inferior_thread ()->step_multi
6050 && inferior_thread ()->control
.stop_step
)
6053 target_terminal_ours ();
6054 async_enable_stdin ();
6056 /* Set the current source location. This will also happen if we
6057 display the frame below, but the current SAL will be incorrect
6058 during a user hook-stop function. */
6059 if (has_stack_frames () && !stop_stack_dummy
)
6060 set_current_sal_from_frame (get_current_frame (), 1);
6062 /* Let the user/frontend see the threads as stopped. */
6063 do_cleanups (old_chain
);
6065 /* Look up the hook_stop and run it (CLI internally handles problem
6066 of stop_command's pre-hook not existing). */
6068 catch_errors (hook_stop_stub
, stop_command
,
6069 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
6071 if (!has_stack_frames ())
6074 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
6075 || last
.kind
== TARGET_WAITKIND_EXITED
)
6078 /* Select innermost stack frame - i.e., current frame is frame 0,
6079 and current location is based on that.
6080 Don't do this on return from a stack dummy routine,
6081 or if the program has exited. */
6083 if (!stop_stack_dummy
)
6085 select_frame (get_current_frame ());
6087 /* Print current location without a level number, if
6088 we have changed functions or hit a breakpoint.
6089 Print source line if we have one.
6090 bpstat_print() contains the logic deciding in detail
6091 what to print, based on the event(s) that just occurred. */
6093 /* If --batch-silent is enabled then there's no need to print the current
6094 source location, and to try risks causing an error message about
6095 missing source files. */
6096 if (stop_print_frame
&& !batch_silent
)
6100 int do_frame_printing
= 1;
6101 struct thread_info
*tp
= inferior_thread ();
6103 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, last
.kind
);
6107 /* FIXME: cagney/2002-12-01: Given that a frame ID does
6108 (or should) carry around the function and does (or
6109 should) use that when doing a frame comparison. */
6110 if (tp
->control
.stop_step
6111 && frame_id_eq (tp
->control
.step_frame_id
,
6112 get_frame_id (get_current_frame ()))
6113 && step_start_function
== find_pc_function (stop_pc
))
6114 source_flag
= SRC_LINE
; /* Finished step, just
6115 print source line. */
6117 source_flag
= SRC_AND_LOC
; /* Print location and
6120 case PRINT_SRC_AND_LOC
:
6121 source_flag
= SRC_AND_LOC
; /* Print location and
6124 case PRINT_SRC_ONLY
:
6125 source_flag
= SRC_LINE
;
6128 source_flag
= SRC_LINE
; /* something bogus */
6129 do_frame_printing
= 0;
6132 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6135 /* The behavior of this routine with respect to the source
6137 SRC_LINE: Print only source line
6138 LOCATION: Print only location
6139 SRC_AND_LOC: Print location and source line. */
6140 if (do_frame_printing
)
6141 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
6143 /* Display the auto-display expressions. */
6148 /* Save the function value return registers, if we care.
6149 We might be about to restore their previous contents. */
6150 if (inferior_thread ()->control
.proceed_to_finish
6151 && execution_direction
!= EXEC_REVERSE
)
6153 /* This should not be necessary. */
6155 regcache_xfree (stop_registers
);
6157 /* NB: The copy goes through to the target picking up the value of
6158 all the registers. */
6159 stop_registers
= regcache_dup (get_current_regcache ());
6162 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6164 /* Pop the empty frame that contains the stack dummy.
6165 This also restores inferior state prior to the call
6166 (struct infcall_suspend_state). */
6167 struct frame_info
*frame
= get_current_frame ();
6169 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6171 /* frame_pop() calls reinit_frame_cache as the last thing it
6172 does which means there's currently no selected frame. We
6173 don't need to re-establish a selected frame if the dummy call
6174 returns normally, that will be done by
6175 restore_infcall_control_state. However, we do have to handle
6176 the case where the dummy call is returning after being
6177 stopped (e.g. the dummy call previously hit a breakpoint).
6178 We can't know which case we have so just always re-establish
6179 a selected frame here. */
6180 select_frame (get_current_frame ());
6184 annotate_stopped ();
6186 /* Suppress the stop observer if we're in the middle of:
6188 - a step n (n > 1), as there still more steps to be done.
6190 - a "finish" command, as the observer will be called in
6191 finish_command_continuation, so it can include the inferior
6192 function's return value.
6194 - calling an inferior function, as we pretend we inferior didn't
6195 run at all. The return value of the call is handled by the
6196 expression evaluator, through call_function_by_hand. */
6198 if (!target_has_execution
6199 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6200 || last
.kind
== TARGET_WAITKIND_EXITED
6201 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6202 || (!(inferior_thread ()->step_multi
6203 && inferior_thread ()->control
.stop_step
)
6204 && !(inferior_thread ()->control
.stop_bpstat
6205 && inferior_thread ()->control
.proceed_to_finish
)
6206 && !inferior_thread ()->control
.in_infcall
))
6208 if (!ptid_equal (inferior_ptid
, null_ptid
))
6209 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6212 observer_notify_normal_stop (NULL
, stop_print_frame
);
6215 if (target_has_execution
)
6217 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6218 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6219 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6220 Delete any breakpoint that is to be deleted at the next stop. */
6221 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6224 /* Try to get rid of automatically added inferiors that are no
6225 longer needed. Keeping those around slows down things linearly.
6226 Note that this never removes the current inferior. */
6231 hook_stop_stub (void *cmd
)
6233 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6238 signal_stop_state (int signo
)
6240 return signal_stop
[signo
];
6244 signal_print_state (int signo
)
6246 return signal_print
[signo
];
6250 signal_pass_state (int signo
)
6252 return signal_program
[signo
];
6256 signal_cache_update (int signo
)
6260 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6261 signal_cache_update (signo
);
6266 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6267 && signal_print
[signo
] == 0
6268 && signal_program
[signo
] == 1
6269 && signal_catch
[signo
] == 0);
6273 signal_stop_update (int signo
, int state
)
6275 int ret
= signal_stop
[signo
];
6277 signal_stop
[signo
] = state
;
6278 signal_cache_update (signo
);
6283 signal_print_update (int signo
, int state
)
6285 int ret
= signal_print
[signo
];
6287 signal_print
[signo
] = state
;
6288 signal_cache_update (signo
);
6293 signal_pass_update (int signo
, int state
)
6295 int ret
= signal_program
[signo
];
6297 signal_program
[signo
] = state
;
6298 signal_cache_update (signo
);
6302 /* Update the global 'signal_catch' from INFO and notify the
6306 signal_catch_update (const unsigned int *info
)
6310 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
6311 signal_catch
[i
] = info
[i
] > 0;
6312 signal_cache_update (-1);
6313 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6317 sig_print_header (void)
6319 printf_filtered (_("Signal Stop\tPrint\tPass "
6320 "to program\tDescription\n"));
6324 sig_print_info (enum gdb_signal oursig
)
6326 const char *name
= gdb_signal_to_name (oursig
);
6327 int name_padding
= 13 - strlen (name
);
6329 if (name_padding
<= 0)
6332 printf_filtered ("%s", name
);
6333 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6334 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6335 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6336 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6337 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6340 /* Specify how various signals in the inferior should be handled. */
6343 handle_command (char *args
, int from_tty
)
6346 int digits
, wordlen
;
6347 int sigfirst
, signum
, siglast
;
6348 enum gdb_signal oursig
;
6351 unsigned char *sigs
;
6352 struct cleanup
*old_chain
;
6356 error_no_arg (_("signal to handle"));
6359 /* Allocate and zero an array of flags for which signals to handle. */
6361 nsigs
= (int) GDB_SIGNAL_LAST
;
6362 sigs
= (unsigned char *) alloca (nsigs
);
6363 memset (sigs
, 0, nsigs
);
6365 /* Break the command line up into args. */
6367 argv
= gdb_buildargv (args
);
6368 old_chain
= make_cleanup_freeargv (argv
);
6370 /* Walk through the args, looking for signal oursigs, signal names, and
6371 actions. Signal numbers and signal names may be interspersed with
6372 actions, with the actions being performed for all signals cumulatively
6373 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6375 while (*argv
!= NULL
)
6377 wordlen
= strlen (*argv
);
6378 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6382 sigfirst
= siglast
= -1;
6384 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6386 /* Apply action to all signals except those used by the
6387 debugger. Silently skip those. */
6390 siglast
= nsigs
- 1;
6392 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6394 SET_SIGS (nsigs
, sigs
, signal_stop
);
6395 SET_SIGS (nsigs
, sigs
, signal_print
);
6397 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6399 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6401 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6403 SET_SIGS (nsigs
, sigs
, signal_print
);
6405 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6407 SET_SIGS (nsigs
, sigs
, signal_program
);
6409 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6411 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6413 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6415 SET_SIGS (nsigs
, sigs
, signal_program
);
6417 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6419 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6420 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6422 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6424 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6426 else if (digits
> 0)
6428 /* It is numeric. The numeric signal refers to our own
6429 internal signal numbering from target.h, not to host/target
6430 signal number. This is a feature; users really should be
6431 using symbolic names anyway, and the common ones like
6432 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6434 sigfirst
= siglast
= (int)
6435 gdb_signal_from_command (atoi (*argv
));
6436 if ((*argv
)[digits
] == '-')
6439 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6441 if (sigfirst
> siglast
)
6443 /* Bet he didn't figure we'd think of this case... */
6451 oursig
= gdb_signal_from_name (*argv
);
6452 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6454 sigfirst
= siglast
= (int) oursig
;
6458 /* Not a number and not a recognized flag word => complain. */
6459 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6463 /* If any signal numbers or symbol names were found, set flags for
6464 which signals to apply actions to. */
6466 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6468 switch ((enum gdb_signal
) signum
)
6470 case GDB_SIGNAL_TRAP
:
6471 case GDB_SIGNAL_INT
:
6472 if (!allsigs
&& !sigs
[signum
])
6474 if (query (_("%s is used by the debugger.\n\
6475 Are you sure you want to change it? "),
6476 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6482 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6483 gdb_flush (gdb_stdout
);
6488 case GDB_SIGNAL_DEFAULT
:
6489 case GDB_SIGNAL_UNKNOWN
:
6490 /* Make sure that "all" doesn't print these. */
6501 for (signum
= 0; signum
< nsigs
; signum
++)
6504 signal_cache_update (-1);
6505 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6506 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
6510 /* Show the results. */
6511 sig_print_header ();
6512 for (; signum
< nsigs
; signum
++)
6514 sig_print_info (signum
);
6520 do_cleanups (old_chain
);
6523 /* Complete the "handle" command. */
6525 static VEC (char_ptr
) *
6526 handle_completer (struct cmd_list_element
*ignore
,
6527 const char *text
, const char *word
)
6529 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
6530 static const char * const keywords
[] =
6544 vec_signals
= signal_completer (ignore
, text
, word
);
6545 vec_keywords
= complete_on_enum (keywords
, word
, word
);
6547 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
6548 VEC_free (char_ptr
, vec_signals
);
6549 VEC_free (char_ptr
, vec_keywords
);
6554 xdb_handle_command (char *args
, int from_tty
)
6557 struct cleanup
*old_chain
;
6560 error_no_arg (_("xdb command"));
6562 /* Break the command line up into args. */
6564 argv
= gdb_buildargv (args
);
6565 old_chain
= make_cleanup_freeargv (argv
);
6566 if (argv
[1] != (char *) NULL
)
6571 bufLen
= strlen (argv
[0]) + 20;
6572 argBuf
= (char *) xmalloc (bufLen
);
6576 enum gdb_signal oursig
;
6578 oursig
= gdb_signal_from_name (argv
[0]);
6579 memset (argBuf
, 0, bufLen
);
6580 if (strcmp (argv
[1], "Q") == 0)
6581 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6584 if (strcmp (argv
[1], "s") == 0)
6586 if (!signal_stop
[oursig
])
6587 sprintf (argBuf
, "%s %s", argv
[0], "stop");
6589 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
6591 else if (strcmp (argv
[1], "i") == 0)
6593 if (!signal_program
[oursig
])
6594 sprintf (argBuf
, "%s %s", argv
[0], "pass");
6596 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
6598 else if (strcmp (argv
[1], "r") == 0)
6600 if (!signal_print
[oursig
])
6601 sprintf (argBuf
, "%s %s", argv
[0], "print");
6603 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6609 handle_command (argBuf
, from_tty
);
6611 printf_filtered (_("Invalid signal handling flag.\n"));
6616 do_cleanups (old_chain
);
6620 gdb_signal_from_command (int num
)
6622 if (num
>= 1 && num
<= 15)
6623 return (enum gdb_signal
) num
;
6624 error (_("Only signals 1-15 are valid as numeric signals.\n\
6625 Use \"info signals\" for a list of symbolic signals."));
6628 /* Print current contents of the tables set by the handle command.
6629 It is possible we should just be printing signals actually used
6630 by the current target (but for things to work right when switching
6631 targets, all signals should be in the signal tables). */
6634 signals_info (char *signum_exp
, int from_tty
)
6636 enum gdb_signal oursig
;
6638 sig_print_header ();
6642 /* First see if this is a symbol name. */
6643 oursig
= gdb_signal_from_name (signum_exp
);
6644 if (oursig
== GDB_SIGNAL_UNKNOWN
)
6646 /* No, try numeric. */
6648 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
6650 sig_print_info (oursig
);
6654 printf_filtered ("\n");
6655 /* These ugly casts brought to you by the native VAX compiler. */
6656 for (oursig
= GDB_SIGNAL_FIRST
;
6657 (int) oursig
< (int) GDB_SIGNAL_LAST
;
6658 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
6662 if (oursig
!= GDB_SIGNAL_UNKNOWN
6663 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
6664 sig_print_info (oursig
);
6667 printf_filtered (_("\nUse the \"handle\" command "
6668 "to change these tables.\n"));
6671 /* Check if it makes sense to read $_siginfo from the current thread
6672 at this point. If not, throw an error. */
6675 validate_siginfo_access (void)
6677 /* No current inferior, no siginfo. */
6678 if (ptid_equal (inferior_ptid
, null_ptid
))
6679 error (_("No thread selected."));
6681 /* Don't try to read from a dead thread. */
6682 if (is_exited (inferior_ptid
))
6683 error (_("The current thread has terminated"));
6685 /* ... or from a spinning thread. */
6686 if (is_running (inferior_ptid
))
6687 error (_("Selected thread is running."));
6690 /* The $_siginfo convenience variable is a bit special. We don't know
6691 for sure the type of the value until we actually have a chance to
6692 fetch the data. The type can change depending on gdbarch, so it is
6693 also dependent on which thread you have selected.
6695 1. making $_siginfo be an internalvar that creates a new value on
6698 2. making the value of $_siginfo be an lval_computed value. */
6700 /* This function implements the lval_computed support for reading a
6704 siginfo_value_read (struct value
*v
)
6706 LONGEST transferred
;
6708 validate_siginfo_access ();
6711 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
6713 value_contents_all_raw (v
),
6715 TYPE_LENGTH (value_type (v
)));
6717 if (transferred
!= TYPE_LENGTH (value_type (v
)))
6718 error (_("Unable to read siginfo"));
6721 /* This function implements the lval_computed support for writing a
6725 siginfo_value_write (struct value
*v
, struct value
*fromval
)
6727 LONGEST transferred
;
6729 validate_siginfo_access ();
6731 transferred
= target_write (¤t_target
,
6732 TARGET_OBJECT_SIGNAL_INFO
,
6734 value_contents_all_raw (fromval
),
6736 TYPE_LENGTH (value_type (fromval
)));
6738 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
6739 error (_("Unable to write siginfo"));
6742 static const struct lval_funcs siginfo_value_funcs
=
6748 /* Return a new value with the correct type for the siginfo object of
6749 the current thread using architecture GDBARCH. Return a void value
6750 if there's no object available. */
6752 static struct value
*
6753 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
6756 if (target_has_stack
6757 && !ptid_equal (inferior_ptid
, null_ptid
)
6758 && gdbarch_get_siginfo_type_p (gdbarch
))
6760 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6762 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
6765 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
6769 /* infcall_suspend_state contains state about the program itself like its
6770 registers and any signal it received when it last stopped.
6771 This state must be restored regardless of how the inferior function call
6772 ends (either successfully, or after it hits a breakpoint or signal)
6773 if the program is to properly continue where it left off. */
6775 struct infcall_suspend_state
6777 struct thread_suspend_state thread_suspend
;
6778 #if 0 /* Currently unused and empty structures are not valid C. */
6779 struct inferior_suspend_state inferior_suspend
;
6784 struct regcache
*registers
;
6786 /* Format of SIGINFO_DATA or NULL if it is not present. */
6787 struct gdbarch
*siginfo_gdbarch
;
6789 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6790 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6791 content would be invalid. */
6792 gdb_byte
*siginfo_data
;
6795 struct infcall_suspend_state
*
6796 save_infcall_suspend_state (void)
6798 struct infcall_suspend_state
*inf_state
;
6799 struct thread_info
*tp
= inferior_thread ();
6801 struct inferior
*inf
= current_inferior ();
6803 struct regcache
*regcache
= get_current_regcache ();
6804 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6805 gdb_byte
*siginfo_data
= NULL
;
6807 if (gdbarch_get_siginfo_type_p (gdbarch
))
6809 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6810 size_t len
= TYPE_LENGTH (type
);
6811 struct cleanup
*back_to
;
6813 siginfo_data
= xmalloc (len
);
6814 back_to
= make_cleanup (xfree
, siginfo_data
);
6816 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6817 siginfo_data
, 0, len
) == len
)
6818 discard_cleanups (back_to
);
6821 /* Errors ignored. */
6822 do_cleanups (back_to
);
6823 siginfo_data
= NULL
;
6827 inf_state
= XZALLOC (struct infcall_suspend_state
);
6831 inf_state
->siginfo_gdbarch
= gdbarch
;
6832 inf_state
->siginfo_data
= siginfo_data
;
6835 inf_state
->thread_suspend
= tp
->suspend
;
6836 #if 0 /* Currently unused and empty structures are not valid C. */
6837 inf_state
->inferior_suspend
= inf
->suspend
;
6840 /* run_inferior_call will not use the signal due to its `proceed' call with
6841 GDB_SIGNAL_0 anyway. */
6842 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6844 inf_state
->stop_pc
= stop_pc
;
6846 inf_state
->registers
= regcache_dup (regcache
);
6851 /* Restore inferior session state to INF_STATE. */
6854 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6856 struct thread_info
*tp
= inferior_thread ();
6858 struct inferior
*inf
= current_inferior ();
6860 struct regcache
*regcache
= get_current_regcache ();
6861 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6863 tp
->suspend
= inf_state
->thread_suspend
;
6864 #if 0 /* Currently unused and empty structures are not valid C. */
6865 inf
->suspend
= inf_state
->inferior_suspend
;
6868 stop_pc
= inf_state
->stop_pc
;
6870 if (inf_state
->siginfo_gdbarch
== gdbarch
)
6872 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6874 /* Errors ignored. */
6875 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6876 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
6879 /* The inferior can be gone if the user types "print exit(0)"
6880 (and perhaps other times). */
6881 if (target_has_execution
)
6882 /* NB: The register write goes through to the target. */
6883 regcache_cpy (regcache
, inf_state
->registers
);
6885 discard_infcall_suspend_state (inf_state
);
6889 do_restore_infcall_suspend_state_cleanup (void *state
)
6891 restore_infcall_suspend_state (state
);
6895 make_cleanup_restore_infcall_suspend_state
6896 (struct infcall_suspend_state
*inf_state
)
6898 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
6902 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6904 regcache_xfree (inf_state
->registers
);
6905 xfree (inf_state
->siginfo_data
);
6910 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
6912 return inf_state
->registers
;
6915 /* infcall_control_state contains state regarding gdb's control of the
6916 inferior itself like stepping control. It also contains session state like
6917 the user's currently selected frame. */
6919 struct infcall_control_state
6921 struct thread_control_state thread_control
;
6922 struct inferior_control_state inferior_control
;
6925 enum stop_stack_kind stop_stack_dummy
;
6926 int stopped_by_random_signal
;
6927 int stop_after_trap
;
6929 /* ID if the selected frame when the inferior function call was made. */
6930 struct frame_id selected_frame_id
;
6933 /* Save all of the information associated with the inferior<==>gdb
6936 struct infcall_control_state
*
6937 save_infcall_control_state (void)
6939 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
6940 struct thread_info
*tp
= inferior_thread ();
6941 struct inferior
*inf
= current_inferior ();
6943 inf_status
->thread_control
= tp
->control
;
6944 inf_status
->inferior_control
= inf
->control
;
6946 tp
->control
.step_resume_breakpoint
= NULL
;
6947 tp
->control
.exception_resume_breakpoint
= NULL
;
6949 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6950 chain. If caller's caller is walking the chain, they'll be happier if we
6951 hand them back the original chain when restore_infcall_control_state is
6953 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
6956 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
6957 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
6958 inf_status
->stop_after_trap
= stop_after_trap
;
6960 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
6966 restore_selected_frame (void *args
)
6968 struct frame_id
*fid
= (struct frame_id
*) args
;
6969 struct frame_info
*frame
;
6971 frame
= frame_find_by_id (*fid
);
6973 /* If inf_status->selected_frame_id is NULL, there was no previously
6977 warning (_("Unable to restore previously selected frame."));
6981 select_frame (frame
);
6986 /* Restore inferior session state to INF_STATUS. */
6989 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
6991 struct thread_info
*tp
= inferior_thread ();
6992 struct inferior
*inf
= current_inferior ();
6994 if (tp
->control
.step_resume_breakpoint
)
6995 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
6997 if (tp
->control
.exception_resume_breakpoint
)
6998 tp
->control
.exception_resume_breakpoint
->disposition
6999 = disp_del_at_next_stop
;
7001 /* Handle the bpstat_copy of the chain. */
7002 bpstat_clear (&tp
->control
.stop_bpstat
);
7004 tp
->control
= inf_status
->thread_control
;
7005 inf
->control
= inf_status
->inferior_control
;
7008 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
7009 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
7010 stop_after_trap
= inf_status
->stop_after_trap
;
7012 if (target_has_stack
)
7014 /* The point of catch_errors is that if the stack is clobbered,
7015 walking the stack might encounter a garbage pointer and
7016 error() trying to dereference it. */
7018 (restore_selected_frame
, &inf_status
->selected_frame_id
,
7019 "Unable to restore previously selected frame:\n",
7020 RETURN_MASK_ERROR
) == 0)
7021 /* Error in restoring the selected frame. Select the innermost
7023 select_frame (get_current_frame ());
7030 do_restore_infcall_control_state_cleanup (void *sts
)
7032 restore_infcall_control_state (sts
);
7036 make_cleanup_restore_infcall_control_state
7037 (struct infcall_control_state
*inf_status
)
7039 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
7043 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
7045 if (inf_status
->thread_control
.step_resume_breakpoint
)
7046 inf_status
->thread_control
.step_resume_breakpoint
->disposition
7047 = disp_del_at_next_stop
;
7049 if (inf_status
->thread_control
.exception_resume_breakpoint
)
7050 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
7051 = disp_del_at_next_stop
;
7053 /* See save_infcall_control_state for info on stop_bpstat. */
7054 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
7060 ptid_match (ptid_t ptid
, ptid_t filter
)
7062 if (ptid_equal (filter
, minus_one_ptid
))
7064 if (ptid_is_pid (filter
)
7065 && ptid_get_pid (ptid
) == ptid_get_pid (filter
))
7067 else if (ptid_equal (ptid
, filter
))
7073 /* restore_inferior_ptid() will be used by the cleanup machinery
7074 to restore the inferior_ptid value saved in a call to
7075 save_inferior_ptid(). */
7078 restore_inferior_ptid (void *arg
)
7080 ptid_t
*saved_ptid_ptr
= arg
;
7082 inferior_ptid
= *saved_ptid_ptr
;
7086 /* Save the value of inferior_ptid so that it may be restored by a
7087 later call to do_cleanups(). Returns the struct cleanup pointer
7088 needed for later doing the cleanup. */
7091 save_inferior_ptid (void)
7093 ptid_t
*saved_ptid_ptr
;
7095 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
7096 *saved_ptid_ptr
= inferior_ptid
;
7097 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
7100 /* See inferior.h. */
7103 clear_exit_convenience_vars (void)
7105 clear_internalvar (lookup_internalvar ("_exitsignal"));
7106 clear_internalvar (lookup_internalvar ("_exitcode"));
7110 /* User interface for reverse debugging:
7111 Set exec-direction / show exec-direction commands
7112 (returns error unless target implements to_set_exec_direction method). */
7114 int execution_direction
= EXEC_FORWARD
;
7115 static const char exec_forward
[] = "forward";
7116 static const char exec_reverse
[] = "reverse";
7117 static const char *exec_direction
= exec_forward
;
7118 static const char *const exec_direction_names
[] = {
7125 set_exec_direction_func (char *args
, int from_tty
,
7126 struct cmd_list_element
*cmd
)
7128 if (target_can_execute_reverse
)
7130 if (!strcmp (exec_direction
, exec_forward
))
7131 execution_direction
= EXEC_FORWARD
;
7132 else if (!strcmp (exec_direction
, exec_reverse
))
7133 execution_direction
= EXEC_REVERSE
;
7137 exec_direction
= exec_forward
;
7138 error (_("Target does not support this operation."));
7143 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7144 struct cmd_list_element
*cmd
, const char *value
)
7146 switch (execution_direction
) {
7148 fprintf_filtered (out
, _("Forward.\n"));
7151 fprintf_filtered (out
, _("Reverse.\n"));
7154 internal_error (__FILE__
, __LINE__
,
7155 _("bogus execution_direction value: %d"),
7156 (int) execution_direction
);
7161 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7162 struct cmd_list_element
*c
, const char *value
)
7164 fprintf_filtered (file
, _("Resuming the execution of threads "
7165 "of all processes is %s.\n"), value
);
7168 /* Implementation of `siginfo' variable. */
7170 static const struct internalvar_funcs siginfo_funcs
=
7178 _initialize_infrun (void)
7182 struct cmd_list_element
*c
;
7184 add_info ("signals", signals_info
, _("\
7185 What debugger does when program gets various signals.\n\
7186 Specify a signal as argument to print info on that signal only."));
7187 add_info_alias ("handle", "signals", 0);
7189 c
= add_com ("handle", class_run
, handle_command
, _("\
7190 Specify how to handle signals.\n\
7191 Usage: handle SIGNAL [ACTIONS]\n\
7192 Args are signals and actions to apply to those signals.\n\
7193 If no actions are specified, the current settings for the specified signals\n\
7194 will be displayed instead.\n\
7196 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7197 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7198 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7199 The special arg \"all\" is recognized to mean all signals except those\n\
7200 used by the debugger, typically SIGTRAP and SIGINT.\n\
7202 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7203 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7204 Stop means reenter debugger if this signal happens (implies print).\n\
7205 Print means print a message if this signal happens.\n\
7206 Pass means let program see this signal; otherwise program doesn't know.\n\
7207 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7208 Pass and Stop may be combined.\n\
7210 Multiple signals may be specified. Signal numbers and signal names\n\
7211 may be interspersed with actions, with the actions being performed for\n\
7212 all signals cumulatively specified."));
7213 set_cmd_completer (c
, handle_completer
);
7217 add_com ("lz", class_info
, signals_info
, _("\
7218 What debugger does when program gets various signals.\n\
7219 Specify a signal as argument to print info on that signal only."));
7220 add_com ("z", class_run
, xdb_handle_command
, _("\
7221 Specify how to handle a signal.\n\
7222 Args are signals and actions to apply to those signals.\n\
7223 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7224 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7225 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7226 The special arg \"all\" is recognized to mean all signals except those\n\
7227 used by the debugger, typically SIGTRAP and SIGINT.\n\
7228 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7229 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7230 nopass), \"Q\" (noprint)\n\
7231 Stop means reenter debugger if this signal happens (implies print).\n\
7232 Print means print a message if this signal happens.\n\
7233 Pass means let program see this signal; otherwise program doesn't know.\n\
7234 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7235 Pass and Stop may be combined."));
7239 stop_command
= add_cmd ("stop", class_obscure
,
7240 not_just_help_class_command
, _("\
7241 There is no `stop' command, but you can set a hook on `stop'.\n\
7242 This allows you to set a list of commands to be run each time execution\n\
7243 of the program stops."), &cmdlist
);
7245 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7246 Set inferior debugging."), _("\
7247 Show inferior debugging."), _("\
7248 When non-zero, inferior specific debugging is enabled."),
7251 &setdebuglist
, &showdebuglist
);
7253 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7254 &debug_displaced
, _("\
7255 Set displaced stepping debugging."), _("\
7256 Show displaced stepping debugging."), _("\
7257 When non-zero, displaced stepping specific debugging is enabled."),
7259 show_debug_displaced
,
7260 &setdebuglist
, &showdebuglist
);
7262 add_setshow_boolean_cmd ("non-stop", no_class
,
7264 Set whether gdb controls the inferior in non-stop mode."), _("\
7265 Show whether gdb controls the inferior in non-stop mode."), _("\
7266 When debugging a multi-threaded program and this setting is\n\
7267 off (the default, also called all-stop mode), when one thread stops\n\
7268 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7269 all other threads in the program while you interact with the thread of\n\
7270 interest. When you continue or step a thread, you can allow the other\n\
7271 threads to run, or have them remain stopped, but while you inspect any\n\
7272 thread's state, all threads stop.\n\
7274 In non-stop mode, when one thread stops, other threads can continue\n\
7275 to run freely. You'll be able to step each thread independently,\n\
7276 leave it stopped or free to run as needed."),
7282 numsigs
= (int) GDB_SIGNAL_LAST
;
7283 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7284 signal_print
= (unsigned char *)
7285 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7286 signal_program
= (unsigned char *)
7287 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7288 signal_catch
= (unsigned char *)
7289 xmalloc (sizeof (signal_catch
[0]) * numsigs
);
7290 signal_pass
= (unsigned char *)
7291 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7292 for (i
= 0; i
< numsigs
; i
++)
7295 signal_print
[i
] = 1;
7296 signal_program
[i
] = 1;
7297 signal_catch
[i
] = 0;
7300 /* Signals caused by debugger's own actions
7301 should not be given to the program afterwards. */
7302 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7303 signal_program
[GDB_SIGNAL_INT
] = 0;
7305 /* Signals that are not errors should not normally enter the debugger. */
7306 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7307 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7308 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7309 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7310 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7311 signal_print
[GDB_SIGNAL_PROF
] = 0;
7312 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7313 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7314 signal_stop
[GDB_SIGNAL_IO
] = 0;
7315 signal_print
[GDB_SIGNAL_IO
] = 0;
7316 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7317 signal_print
[GDB_SIGNAL_POLL
] = 0;
7318 signal_stop
[GDB_SIGNAL_URG
] = 0;
7319 signal_print
[GDB_SIGNAL_URG
] = 0;
7320 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7321 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7322 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7323 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7325 /* These signals are used internally by user-level thread
7326 implementations. (See signal(5) on Solaris.) Like the above
7327 signals, a healthy program receives and handles them as part of
7328 its normal operation. */
7329 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7330 signal_print
[GDB_SIGNAL_LWP
] = 0;
7331 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7332 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7333 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7334 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7336 /* Update cached state. */
7337 signal_cache_update (-1);
7339 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7340 &stop_on_solib_events
, _("\
7341 Set stopping for shared library events."), _("\
7342 Show stopping for shared library events."), _("\
7343 If nonzero, gdb will give control to the user when the dynamic linker\n\
7344 notifies gdb of shared library events. The most common event of interest\n\
7345 to the user would be loading/unloading of a new library."),
7346 set_stop_on_solib_events
,
7347 show_stop_on_solib_events
,
7348 &setlist
, &showlist
);
7350 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7351 follow_fork_mode_kind_names
,
7352 &follow_fork_mode_string
, _("\
7353 Set debugger response to a program call of fork or vfork."), _("\
7354 Show debugger response to a program call of fork or vfork."), _("\
7355 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7356 parent - the original process is debugged after a fork\n\
7357 child - the new process is debugged after a fork\n\
7358 The unfollowed process will continue to run.\n\
7359 By default, the debugger will follow the parent process."),
7361 show_follow_fork_mode_string
,
7362 &setlist
, &showlist
);
7364 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7365 follow_exec_mode_names
,
7366 &follow_exec_mode_string
, _("\
7367 Set debugger response to a program call of exec."), _("\
7368 Show debugger response to a program call of exec."), _("\
7369 An exec call replaces the program image of a process.\n\
7371 follow-exec-mode can be:\n\
7373 new - the debugger creates a new inferior and rebinds the process\n\
7374 to this new inferior. The program the process was running before\n\
7375 the exec call can be restarted afterwards by restarting the original\n\
7378 same - the debugger keeps the process bound to the same inferior.\n\
7379 The new executable image replaces the previous executable loaded in\n\
7380 the inferior. Restarting the inferior after the exec call restarts\n\
7381 the executable the process was running after the exec call.\n\
7383 By default, the debugger will use the same inferior."),
7385 show_follow_exec_mode_string
,
7386 &setlist
, &showlist
);
7388 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7389 scheduler_enums
, &scheduler_mode
, _("\
7390 Set mode for locking scheduler during execution."), _("\
7391 Show mode for locking scheduler during execution."), _("\
7392 off == no locking (threads may preempt at any time)\n\
7393 on == full locking (no thread except the current thread may run)\n\
7394 step == scheduler locked during every single-step operation.\n\
7395 In this mode, no other thread may run during a step command.\n\
7396 Other threads may run while stepping over a function call ('next')."),
7397 set_schedlock_func
, /* traps on target vector */
7398 show_scheduler_mode
,
7399 &setlist
, &showlist
);
7401 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7402 Set mode for resuming threads of all processes."), _("\
7403 Show mode for resuming threads of all processes."), _("\
7404 When on, execution commands (such as 'continue' or 'next') resume all\n\
7405 threads of all processes. When off (which is the default), execution\n\
7406 commands only resume the threads of the current process. The set of\n\
7407 threads that are resumed is further refined by the scheduler-locking\n\
7408 mode (see help set scheduler-locking)."),
7410 show_schedule_multiple
,
7411 &setlist
, &showlist
);
7413 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7414 Set mode of the step operation."), _("\
7415 Show mode of the step operation."), _("\
7416 When set, doing a step over a function without debug line information\n\
7417 will stop at the first instruction of that function. Otherwise, the\n\
7418 function is skipped and the step command stops at a different source line."),
7420 show_step_stop_if_no_debug
,
7421 &setlist
, &showlist
);
7423 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
7424 &can_use_displaced_stepping
, _("\
7425 Set debugger's willingness to use displaced stepping."), _("\
7426 Show debugger's willingness to use displaced stepping."), _("\
7427 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7428 supported by the target architecture. If off, gdb will not use displaced\n\
7429 stepping to step over breakpoints, even if such is supported by the target\n\
7430 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7431 if the target architecture supports it and non-stop mode is active, but will not\n\
7432 use it in all-stop mode (see help set non-stop)."),
7434 show_can_use_displaced_stepping
,
7435 &setlist
, &showlist
);
7437 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7438 &exec_direction
, _("Set direction of execution.\n\
7439 Options are 'forward' or 'reverse'."),
7440 _("Show direction of execution (forward/reverse)."),
7441 _("Tells gdb whether to execute forward or backward."),
7442 set_exec_direction_func
, show_exec_direction_func
,
7443 &setlist
, &showlist
);
7445 /* Set/show detach-on-fork: user-settable mode. */
7447 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7448 Set whether gdb will detach the child of a fork."), _("\
7449 Show whether gdb will detach the child of a fork."), _("\
7450 Tells gdb whether to detach the child of a fork."),
7451 NULL
, NULL
, &setlist
, &showlist
);
7453 /* Set/show disable address space randomization mode. */
7455 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7456 &disable_randomization
, _("\
7457 Set disabling of debuggee's virtual address space randomization."), _("\
7458 Show disabling of debuggee's virtual address space randomization."), _("\
7459 When this mode is on (which is the default), randomization of the virtual\n\
7460 address space is disabled. Standalone programs run with the randomization\n\
7461 enabled by default on some platforms."),
7462 &set_disable_randomization
,
7463 &show_disable_randomization
,
7464 &setlist
, &showlist
);
7466 /* ptid initializations */
7467 inferior_ptid
= null_ptid
;
7468 target_last_wait_ptid
= minus_one_ptid
;
7470 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7471 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7472 observer_attach_thread_exit (infrun_thread_thread_exit
);
7473 observer_attach_inferior_exit (infrun_inferior_exit
);
7475 /* Explicitly create without lookup, since that tries to create a
7476 value with a void typed value, and when we get here, gdbarch
7477 isn't initialized yet. At this point, we're quite sure there
7478 isn't another convenience variable of the same name. */
7479 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7481 add_setshow_boolean_cmd ("observer", no_class
,
7482 &observer_mode_1
, _("\
7483 Set whether gdb controls the inferior in observer mode."), _("\
7484 Show whether gdb controls the inferior in observer mode."), _("\
7485 In observer mode, GDB can get data from the inferior, but not\n\
7486 affect its execution. Registers and memory may not be changed,\n\
7487 breakpoints may not be set, and the program cannot be interrupted\n\