1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2015 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
65 /* Prototypes for local functions */
67 static void signals_info (char *, int);
69 static void handle_command (char *, int);
71 static void sig_print_info (enum gdb_signal
);
73 static void sig_print_header (void);
75 static void resume_cleanups (void *);
77 static int hook_stop_stub (void *);
79 static int restore_selected_frame (void *);
81 static int follow_fork (void);
83 static int follow_fork_inferior (int follow_child
, int detach_fork
);
85 static void follow_inferior_reset_breakpoints (void);
87 static void set_schedlock_func (char *args
, int from_tty
,
88 struct cmd_list_element
*c
);
90 static int currently_stepping (struct thread_info
*tp
);
92 void _initialize_infrun (void);
94 void nullify_last_target_wait_ptid (void);
96 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
98 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
100 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
102 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
104 /* When set, stop the 'step' command if we enter a function which has
105 no line number information. The normal behavior is that we step
106 over such function. */
107 int step_stop_if_no_debug
= 0;
109 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
110 struct cmd_list_element
*c
, const char *value
)
112 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
115 /* In asynchronous mode, but simulating synchronous execution. */
117 int sync_execution
= 0;
119 /* proceed and normal_stop use this to notify the user when the
120 inferior stopped in a different thread than it had been running
123 static ptid_t previous_inferior_ptid
;
125 /* If set (default for legacy reasons), when following a fork, GDB
126 will detach from one of the fork branches, child or parent.
127 Exactly which branch is detached depends on 'set follow-fork-mode'
130 static int detach_fork
= 1;
132 int debug_displaced
= 0;
134 show_debug_displaced (struct ui_file
*file
, int from_tty
,
135 struct cmd_list_element
*c
, const char *value
)
137 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
140 unsigned int debug_infrun
= 0;
142 show_debug_infrun (struct ui_file
*file
, int from_tty
,
143 struct cmd_list_element
*c
, const char *value
)
145 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
149 /* Support for disabling address space randomization. */
151 int disable_randomization
= 1;
154 show_disable_randomization (struct ui_file
*file
, int from_tty
,
155 struct cmd_list_element
*c
, const char *value
)
157 if (target_supports_disable_randomization ())
158 fprintf_filtered (file
,
159 _("Disabling randomization of debuggee's "
160 "virtual address space is %s.\n"),
163 fputs_filtered (_("Disabling randomization of debuggee's "
164 "virtual address space is unsupported on\n"
165 "this platform.\n"), file
);
169 set_disable_randomization (char *args
, int from_tty
,
170 struct cmd_list_element
*c
)
172 if (!target_supports_disable_randomization ())
173 error (_("Disabling randomization of debuggee's "
174 "virtual address space is unsupported on\n"
178 /* User interface for non-stop mode. */
181 static int non_stop_1
= 0;
184 set_non_stop (char *args
, int from_tty
,
185 struct cmd_list_element
*c
)
187 if (target_has_execution
)
189 non_stop_1
= non_stop
;
190 error (_("Cannot change this setting while the inferior is running."));
193 non_stop
= non_stop_1
;
197 show_non_stop (struct ui_file
*file
, int from_tty
,
198 struct cmd_list_element
*c
, const char *value
)
200 fprintf_filtered (file
,
201 _("Controlling the inferior in non-stop mode is %s.\n"),
205 /* "Observer mode" is somewhat like a more extreme version of
206 non-stop, in which all GDB operations that might affect the
207 target's execution have been disabled. */
209 int observer_mode
= 0;
210 static int observer_mode_1
= 0;
213 set_observer_mode (char *args
, int from_tty
,
214 struct cmd_list_element
*c
)
216 if (target_has_execution
)
218 observer_mode_1
= observer_mode
;
219 error (_("Cannot change this setting while the inferior is running."));
222 observer_mode
= observer_mode_1
;
224 may_write_registers
= !observer_mode
;
225 may_write_memory
= !observer_mode
;
226 may_insert_breakpoints
= !observer_mode
;
227 may_insert_tracepoints
= !observer_mode
;
228 /* We can insert fast tracepoints in or out of observer mode,
229 but enable them if we're going into this mode. */
231 may_insert_fast_tracepoints
= 1;
232 may_stop
= !observer_mode
;
233 update_target_permissions ();
235 /* Going *into* observer mode we must force non-stop, then
236 going out we leave it that way. */
239 pagination_enabled
= 0;
240 non_stop
= non_stop_1
= 1;
244 printf_filtered (_("Observer mode is now %s.\n"),
245 (observer_mode
? "on" : "off"));
249 show_observer_mode (struct ui_file
*file
, int from_tty
,
250 struct cmd_list_element
*c
, const char *value
)
252 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
255 /* This updates the value of observer mode based on changes in
256 permissions. Note that we are deliberately ignoring the values of
257 may-write-registers and may-write-memory, since the user may have
258 reason to enable these during a session, for instance to turn on a
259 debugging-related global. */
262 update_observer_mode (void)
266 newval
= (!may_insert_breakpoints
267 && !may_insert_tracepoints
268 && may_insert_fast_tracepoints
272 /* Let the user know if things change. */
273 if (newval
!= observer_mode
)
274 printf_filtered (_("Observer mode is now %s.\n"),
275 (newval
? "on" : "off"));
277 observer_mode
= observer_mode_1
= newval
;
280 /* Tables of how to react to signals; the user sets them. */
282 static unsigned char *signal_stop
;
283 static unsigned char *signal_print
;
284 static unsigned char *signal_program
;
286 /* Table of signals that are registered with "catch signal". A
287 non-zero entry indicates that the signal is caught by some "catch
288 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
290 static unsigned char *signal_catch
;
292 /* Table of signals that the target may silently handle.
293 This is automatically determined from the flags above,
294 and simply cached here. */
295 static unsigned char *signal_pass
;
297 #define SET_SIGS(nsigs,sigs,flags) \
299 int signum = (nsigs); \
300 while (signum-- > 0) \
301 if ((sigs)[signum]) \
302 (flags)[signum] = 1; \
305 #define UNSET_SIGS(nsigs,sigs,flags) \
307 int signum = (nsigs); \
308 while (signum-- > 0) \
309 if ((sigs)[signum]) \
310 (flags)[signum] = 0; \
313 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
314 this function is to avoid exporting `signal_program'. */
317 update_signals_program_target (void)
319 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
322 /* Value to pass to target_resume() to cause all threads to resume. */
324 #define RESUME_ALL minus_one_ptid
326 /* Command list pointer for the "stop" placeholder. */
328 static struct cmd_list_element
*stop_command
;
330 /* Nonzero if we want to give control to the user when we're notified
331 of shared library events by the dynamic linker. */
332 int stop_on_solib_events
;
334 /* Enable or disable optional shared library event breakpoints
335 as appropriate when the above flag is changed. */
338 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
340 update_solib_breakpoints ();
344 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
345 struct cmd_list_element
*c
, const char *value
)
347 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
351 /* Nonzero means expecting a trace trap
352 and should stop the inferior and return silently when it happens. */
356 /* Save register contents here when executing a "finish" command or are
357 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
358 Thus this contains the return value from the called function (assuming
359 values are returned in a register). */
361 struct regcache
*stop_registers
;
363 /* Nonzero after stop if current stack frame should be printed. */
365 static int stop_print_frame
;
367 /* This is a cached copy of the pid/waitstatus of the last event
368 returned by target_wait()/deprecated_target_wait_hook(). This
369 information is returned by get_last_target_status(). */
370 static ptid_t target_last_wait_ptid
;
371 static struct target_waitstatus target_last_waitstatus
;
373 static void context_switch (ptid_t ptid
);
375 void init_thread_stepping_state (struct thread_info
*tss
);
377 static const char follow_fork_mode_child
[] = "child";
378 static const char follow_fork_mode_parent
[] = "parent";
380 static const char *const follow_fork_mode_kind_names
[] = {
381 follow_fork_mode_child
,
382 follow_fork_mode_parent
,
386 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
388 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
389 struct cmd_list_element
*c
, const char *value
)
391 fprintf_filtered (file
,
392 _("Debugger response to a program "
393 "call of fork or vfork is \"%s\".\n"),
398 /* Handle changes to the inferior list based on the type of fork,
399 which process is being followed, and whether the other process
400 should be detached. On entry inferior_ptid must be the ptid of
401 the fork parent. At return inferior_ptid is the ptid of the
402 followed inferior. */
405 follow_fork_inferior (int follow_child
, int detach_fork
)
408 ptid_t parent_ptid
, child_ptid
;
410 has_vforked
= (inferior_thread ()->pending_follow
.kind
411 == TARGET_WAITKIND_VFORKED
);
412 parent_ptid
= inferior_ptid
;
413 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
416 && !non_stop
/* Non-stop always resumes both branches. */
417 && (!target_is_async_p () || sync_execution
)
418 && !(follow_child
|| detach_fork
|| sched_multi
))
420 /* The parent stays blocked inside the vfork syscall until the
421 child execs or exits. If we don't let the child run, then
422 the parent stays blocked. If we're telling the parent to run
423 in the foreground, the user will not be able to ctrl-c to get
424 back the terminal, effectively hanging the debug session. */
425 fprintf_filtered (gdb_stderr
, _("\
426 Can not resume the parent process over vfork in the foreground while\n\
427 holding the child stopped. Try \"set detach-on-fork\" or \
428 \"set schedule-multiple\".\n"));
429 /* FIXME output string > 80 columns. */
435 /* Detach new forked process? */
438 struct cleanup
*old_chain
;
440 /* Before detaching from the child, remove all breakpoints
441 from it. If we forked, then this has already been taken
442 care of by infrun.c. If we vforked however, any
443 breakpoint inserted in the parent is visible in the
444 child, even those added while stopped in a vfork
445 catchpoint. This will remove the breakpoints from the
446 parent also, but they'll be reinserted below. */
449 /* Keep breakpoints list in sync. */
450 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
453 if (info_verbose
|| debug_infrun
)
455 target_terminal_ours_for_output ();
456 fprintf_filtered (gdb_stdlog
,
457 _("Detaching after %s from child %s.\n"),
458 has_vforked
? "vfork" : "fork",
459 target_pid_to_str (child_ptid
));
464 struct inferior
*parent_inf
, *child_inf
;
465 struct cleanup
*old_chain
;
467 /* Add process to GDB's tables. */
468 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
470 parent_inf
= current_inferior ();
471 child_inf
->attach_flag
= parent_inf
->attach_flag
;
472 copy_terminal_info (child_inf
, parent_inf
);
473 child_inf
->gdbarch
= parent_inf
->gdbarch
;
474 copy_inferior_target_desc_info (child_inf
, parent_inf
);
476 old_chain
= save_inferior_ptid ();
477 save_current_program_space ();
479 inferior_ptid
= child_ptid
;
480 add_thread (inferior_ptid
);
481 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
483 /* If this is a vfork child, then the address-space is
484 shared with the parent. */
487 child_inf
->pspace
= parent_inf
->pspace
;
488 child_inf
->aspace
= parent_inf
->aspace
;
490 /* The parent will be frozen until the child is done
491 with the shared region. Keep track of the
493 child_inf
->vfork_parent
= parent_inf
;
494 child_inf
->pending_detach
= 0;
495 parent_inf
->vfork_child
= child_inf
;
496 parent_inf
->pending_detach
= 0;
500 child_inf
->aspace
= new_address_space ();
501 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
502 child_inf
->removable
= 1;
503 set_current_program_space (child_inf
->pspace
);
504 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
506 /* Let the shared library layer (e.g., solib-svr4) learn
507 about this new process, relocate the cloned exec, pull
508 in shared libraries, and install the solib event
509 breakpoint. If a "cloned-VM" event was propagated
510 better throughout the core, this wouldn't be
512 solib_create_inferior_hook (0);
515 do_cleanups (old_chain
);
520 struct inferior
*parent_inf
;
522 parent_inf
= current_inferior ();
524 /* If we detached from the child, then we have to be careful
525 to not insert breakpoints in the parent until the child
526 is done with the shared memory region. However, if we're
527 staying attached to the child, then we can and should
528 insert breakpoints, so that we can debug it. A
529 subsequent child exec or exit is enough to know when does
530 the child stops using the parent's address space. */
531 parent_inf
->waiting_for_vfork_done
= detach_fork
;
532 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
537 /* Follow the child. */
538 struct inferior
*parent_inf
, *child_inf
;
539 struct program_space
*parent_pspace
;
541 if (info_verbose
|| debug_infrun
)
543 target_terminal_ours_for_output ();
544 fprintf_filtered (gdb_stdlog
,
545 _("Attaching after %s %s to child %s.\n"),
546 target_pid_to_str (parent_ptid
),
547 has_vforked
? "vfork" : "fork",
548 target_pid_to_str (child_ptid
));
551 /* Add the new inferior first, so that the target_detach below
552 doesn't unpush the target. */
554 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
556 parent_inf
= current_inferior ();
557 child_inf
->attach_flag
= parent_inf
->attach_flag
;
558 copy_terminal_info (child_inf
, parent_inf
);
559 child_inf
->gdbarch
= parent_inf
->gdbarch
;
560 copy_inferior_target_desc_info (child_inf
, parent_inf
);
562 parent_pspace
= parent_inf
->pspace
;
564 /* If we're vforking, we want to hold on to the parent until the
565 child exits or execs. At child exec or exit time we can
566 remove the old breakpoints from the parent and detach or
567 resume debugging it. Otherwise, detach the parent now; we'll
568 want to reuse it's program/address spaces, but we can't set
569 them to the child before removing breakpoints from the
570 parent, otherwise, the breakpoints module could decide to
571 remove breakpoints from the wrong process (since they'd be
572 assigned to the same address space). */
576 gdb_assert (child_inf
->vfork_parent
== NULL
);
577 gdb_assert (parent_inf
->vfork_child
== NULL
);
578 child_inf
->vfork_parent
= parent_inf
;
579 child_inf
->pending_detach
= 0;
580 parent_inf
->vfork_child
= child_inf
;
581 parent_inf
->pending_detach
= detach_fork
;
582 parent_inf
->waiting_for_vfork_done
= 0;
584 else if (detach_fork
)
586 if (info_verbose
|| debug_infrun
)
588 target_terminal_ours_for_output ();
589 fprintf_filtered (gdb_stdlog
,
590 _("Detaching after fork from "
592 target_pid_to_str (child_ptid
));
595 target_detach (NULL
, 0);
598 /* Note that the detach above makes PARENT_INF dangling. */
600 /* Add the child thread to the appropriate lists, and switch to
601 this new thread, before cloning the program space, and
602 informing the solib layer about this new process. */
604 inferior_ptid
= child_ptid
;
605 add_thread (inferior_ptid
);
607 /* If this is a vfork child, then the address-space is shared
608 with the parent. If we detached from the parent, then we can
609 reuse the parent's program/address spaces. */
610 if (has_vforked
|| detach_fork
)
612 child_inf
->pspace
= parent_pspace
;
613 child_inf
->aspace
= child_inf
->pspace
->aspace
;
617 child_inf
->aspace
= new_address_space ();
618 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
619 child_inf
->removable
= 1;
620 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
621 set_current_program_space (child_inf
->pspace
);
622 clone_program_space (child_inf
->pspace
, parent_pspace
);
624 /* Let the shared library layer (e.g., solib-svr4) learn
625 about this new process, relocate the cloned exec, pull in
626 shared libraries, and install the solib event breakpoint.
627 If a "cloned-VM" event was propagated better throughout
628 the core, this wouldn't be required. */
629 solib_create_inferior_hook (0);
633 return target_follow_fork (follow_child
, detach_fork
);
636 /* Tell the target to follow the fork we're stopped at. Returns true
637 if the inferior should be resumed; false, if the target for some
638 reason decided it's best not to resume. */
643 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
644 int should_resume
= 1;
645 struct thread_info
*tp
;
647 /* Copy user stepping state to the new inferior thread. FIXME: the
648 followed fork child thread should have a copy of most of the
649 parent thread structure's run control related fields, not just these.
650 Initialized to avoid "may be used uninitialized" warnings from gcc. */
651 struct breakpoint
*step_resume_breakpoint
= NULL
;
652 struct breakpoint
*exception_resume_breakpoint
= NULL
;
653 CORE_ADDR step_range_start
= 0;
654 CORE_ADDR step_range_end
= 0;
655 struct frame_id step_frame_id
= { 0 };
656 struct interp
*command_interp
= NULL
;
661 struct target_waitstatus wait_status
;
663 /* Get the last target status returned by target_wait(). */
664 get_last_target_status (&wait_ptid
, &wait_status
);
666 /* If not stopped at a fork event, then there's nothing else to
668 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
669 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
672 /* Check if we switched over from WAIT_PTID, since the event was
674 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
675 && !ptid_equal (inferior_ptid
, wait_ptid
))
677 /* We did. Switch back to WAIT_PTID thread, to tell the
678 target to follow it (in either direction). We'll
679 afterwards refuse to resume, and inform the user what
681 switch_to_thread (wait_ptid
);
686 tp
= inferior_thread ();
688 /* If there were any forks/vforks that were caught and are now to be
689 followed, then do so now. */
690 switch (tp
->pending_follow
.kind
)
692 case TARGET_WAITKIND_FORKED
:
693 case TARGET_WAITKIND_VFORKED
:
695 ptid_t parent
, child
;
697 /* If the user did a next/step, etc, over a fork call,
698 preserve the stepping state in the fork child. */
699 if (follow_child
&& should_resume
)
701 step_resume_breakpoint
= clone_momentary_breakpoint
702 (tp
->control
.step_resume_breakpoint
);
703 step_range_start
= tp
->control
.step_range_start
;
704 step_range_end
= tp
->control
.step_range_end
;
705 step_frame_id
= tp
->control
.step_frame_id
;
706 exception_resume_breakpoint
707 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
708 command_interp
= tp
->control
.command_interp
;
710 /* For now, delete the parent's sr breakpoint, otherwise,
711 parent/child sr breakpoints are considered duplicates,
712 and the child version will not be installed. Remove
713 this when the breakpoints module becomes aware of
714 inferiors and address spaces. */
715 delete_step_resume_breakpoint (tp
);
716 tp
->control
.step_range_start
= 0;
717 tp
->control
.step_range_end
= 0;
718 tp
->control
.step_frame_id
= null_frame_id
;
719 delete_exception_resume_breakpoint (tp
);
720 tp
->control
.command_interp
= NULL
;
723 parent
= inferior_ptid
;
724 child
= tp
->pending_follow
.value
.related_pid
;
726 /* Set up inferior(s) as specified by the caller, and tell the
727 target to do whatever is necessary to follow either parent
729 if (follow_fork_inferior (follow_child
, detach_fork
))
731 /* Target refused to follow, or there's some other reason
732 we shouldn't resume. */
737 /* This pending follow fork event is now handled, one way
738 or another. The previous selected thread may be gone
739 from the lists by now, but if it is still around, need
740 to clear the pending follow request. */
741 tp
= find_thread_ptid (parent
);
743 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
745 /* This makes sure we don't try to apply the "Switched
746 over from WAIT_PID" logic above. */
747 nullify_last_target_wait_ptid ();
749 /* If we followed the child, switch to it... */
752 switch_to_thread (child
);
754 /* ... and preserve the stepping state, in case the
755 user was stepping over the fork call. */
758 tp
= inferior_thread ();
759 tp
->control
.step_resume_breakpoint
760 = step_resume_breakpoint
;
761 tp
->control
.step_range_start
= step_range_start
;
762 tp
->control
.step_range_end
= step_range_end
;
763 tp
->control
.step_frame_id
= step_frame_id
;
764 tp
->control
.exception_resume_breakpoint
765 = exception_resume_breakpoint
;
766 tp
->control
.command_interp
= command_interp
;
770 /* If we get here, it was because we're trying to
771 resume from a fork catchpoint, but, the user
772 has switched threads away from the thread that
773 forked. In that case, the resume command
774 issued is most likely not applicable to the
775 child, so just warn, and refuse to resume. */
776 warning (_("Not resuming: switched threads "
777 "before following fork child.\n"));
780 /* Reset breakpoints in the child as appropriate. */
781 follow_inferior_reset_breakpoints ();
784 switch_to_thread (parent
);
788 case TARGET_WAITKIND_SPURIOUS
:
789 /* Nothing to follow. */
792 internal_error (__FILE__
, __LINE__
,
793 "Unexpected pending_follow.kind %d\n",
794 tp
->pending_follow
.kind
);
798 return should_resume
;
802 follow_inferior_reset_breakpoints (void)
804 struct thread_info
*tp
= inferior_thread ();
806 /* Was there a step_resume breakpoint? (There was if the user
807 did a "next" at the fork() call.) If so, explicitly reset its
808 thread number. Cloned step_resume breakpoints are disabled on
809 creation, so enable it here now that it is associated with the
812 step_resumes are a form of bp that are made to be per-thread.
813 Since we created the step_resume bp when the parent process
814 was being debugged, and now are switching to the child process,
815 from the breakpoint package's viewpoint, that's a switch of
816 "threads". We must update the bp's notion of which thread
817 it is for, or it'll be ignored when it triggers. */
819 if (tp
->control
.step_resume_breakpoint
)
821 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
822 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
825 /* Treat exception_resume breakpoints like step_resume breakpoints. */
826 if (tp
->control
.exception_resume_breakpoint
)
828 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
829 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
832 /* Reinsert all breakpoints in the child. The user may have set
833 breakpoints after catching the fork, in which case those
834 were never set in the child, but only in the parent. This makes
835 sure the inserted breakpoints match the breakpoint list. */
837 breakpoint_re_set ();
838 insert_breakpoints ();
841 /* The child has exited or execed: resume threads of the parent the
842 user wanted to be executing. */
845 proceed_after_vfork_done (struct thread_info
*thread
,
848 int pid
= * (int *) arg
;
850 if (ptid_get_pid (thread
->ptid
) == pid
851 && is_running (thread
->ptid
)
852 && !is_executing (thread
->ptid
)
853 && !thread
->stop_requested
854 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
857 fprintf_unfiltered (gdb_stdlog
,
858 "infrun: resuming vfork parent thread %s\n",
859 target_pid_to_str (thread
->ptid
));
861 switch_to_thread (thread
->ptid
);
862 clear_proceed_status (0);
863 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
869 /* Called whenever we notice an exec or exit event, to handle
870 detaching or resuming a vfork parent. */
873 handle_vfork_child_exec_or_exit (int exec
)
875 struct inferior
*inf
= current_inferior ();
877 if (inf
->vfork_parent
)
879 int resume_parent
= -1;
881 /* This exec or exit marks the end of the shared memory region
882 between the parent and the child. If the user wanted to
883 detach from the parent, now is the time. */
885 if (inf
->vfork_parent
->pending_detach
)
887 struct thread_info
*tp
;
888 struct cleanup
*old_chain
;
889 struct program_space
*pspace
;
890 struct address_space
*aspace
;
892 /* follow-fork child, detach-on-fork on. */
894 inf
->vfork_parent
->pending_detach
= 0;
898 /* If we're handling a child exit, then inferior_ptid
899 points at the inferior's pid, not to a thread. */
900 old_chain
= save_inferior_ptid ();
901 save_current_program_space ();
902 save_current_inferior ();
905 old_chain
= save_current_space_and_thread ();
907 /* We're letting loose of the parent. */
908 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
909 switch_to_thread (tp
->ptid
);
911 /* We're about to detach from the parent, which implicitly
912 removes breakpoints from its address space. There's a
913 catch here: we want to reuse the spaces for the child,
914 but, parent/child are still sharing the pspace at this
915 point, although the exec in reality makes the kernel give
916 the child a fresh set of new pages. The problem here is
917 that the breakpoints module being unaware of this, would
918 likely chose the child process to write to the parent
919 address space. Swapping the child temporarily away from
920 the spaces has the desired effect. Yes, this is "sort
923 pspace
= inf
->pspace
;
924 aspace
= inf
->aspace
;
928 if (debug_infrun
|| info_verbose
)
930 target_terminal_ours_for_output ();
934 fprintf_filtered (gdb_stdlog
,
935 _("Detaching vfork parent process "
936 "%d after child exec.\n"),
937 inf
->vfork_parent
->pid
);
941 fprintf_filtered (gdb_stdlog
,
942 _("Detaching vfork parent process "
943 "%d after child exit.\n"),
944 inf
->vfork_parent
->pid
);
948 target_detach (NULL
, 0);
951 inf
->pspace
= pspace
;
952 inf
->aspace
= aspace
;
954 do_cleanups (old_chain
);
958 /* We're staying attached to the parent, so, really give the
959 child a new address space. */
960 inf
->pspace
= add_program_space (maybe_new_address_space ());
961 inf
->aspace
= inf
->pspace
->aspace
;
963 set_current_program_space (inf
->pspace
);
965 resume_parent
= inf
->vfork_parent
->pid
;
967 /* Break the bonds. */
968 inf
->vfork_parent
->vfork_child
= NULL
;
972 struct cleanup
*old_chain
;
973 struct program_space
*pspace
;
975 /* If this is a vfork child exiting, then the pspace and
976 aspaces were shared with the parent. Since we're
977 reporting the process exit, we'll be mourning all that is
978 found in the address space, and switching to null_ptid,
979 preparing to start a new inferior. But, since we don't
980 want to clobber the parent's address/program spaces, we
981 go ahead and create a new one for this exiting
984 /* Switch to null_ptid, so that clone_program_space doesn't want
985 to read the selected frame of a dead process. */
986 old_chain
= save_inferior_ptid ();
987 inferior_ptid
= null_ptid
;
989 /* This inferior is dead, so avoid giving the breakpoints
990 module the option to write through to it (cloning a
991 program space resets breakpoints). */
994 pspace
= add_program_space (maybe_new_address_space ());
995 set_current_program_space (pspace
);
997 inf
->symfile_flags
= SYMFILE_NO_READ
;
998 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
999 inf
->pspace
= pspace
;
1000 inf
->aspace
= pspace
->aspace
;
1002 /* Put back inferior_ptid. We'll continue mourning this
1004 do_cleanups (old_chain
);
1006 resume_parent
= inf
->vfork_parent
->pid
;
1007 /* Break the bonds. */
1008 inf
->vfork_parent
->vfork_child
= NULL
;
1011 inf
->vfork_parent
= NULL
;
1013 gdb_assert (current_program_space
== inf
->pspace
);
1015 if (non_stop
&& resume_parent
!= -1)
1017 /* If the user wanted the parent to be running, let it go
1019 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1022 fprintf_unfiltered (gdb_stdlog
,
1023 "infrun: resuming vfork parent process %d\n",
1026 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1028 do_cleanups (old_chain
);
1033 /* Enum strings for "set|show follow-exec-mode". */
1035 static const char follow_exec_mode_new
[] = "new";
1036 static const char follow_exec_mode_same
[] = "same";
1037 static const char *const follow_exec_mode_names
[] =
1039 follow_exec_mode_new
,
1040 follow_exec_mode_same
,
1044 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1046 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1047 struct cmd_list_element
*c
, const char *value
)
1049 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1052 /* EXECD_PATHNAME is assumed to be non-NULL. */
1055 follow_exec (ptid_t ptid
, char *execd_pathname
)
1057 struct thread_info
*th
, *tmp
;
1058 struct inferior
*inf
= current_inferior ();
1059 int pid
= ptid_get_pid (ptid
);
1061 /* This is an exec event that we actually wish to pay attention to.
1062 Refresh our symbol table to the newly exec'd program, remove any
1063 momentary bp's, etc.
1065 If there are breakpoints, they aren't really inserted now,
1066 since the exec() transformed our inferior into a fresh set
1069 We want to preserve symbolic breakpoints on the list, since
1070 we have hopes that they can be reset after the new a.out's
1071 symbol table is read.
1073 However, any "raw" breakpoints must be removed from the list
1074 (e.g., the solib bp's), since their address is probably invalid
1077 And, we DON'T want to call delete_breakpoints() here, since
1078 that may write the bp's "shadow contents" (the instruction
1079 value that was overwritten witha TRAP instruction). Since
1080 we now have a new a.out, those shadow contents aren't valid. */
1082 mark_breakpoints_out ();
1084 /* The target reports the exec event to the main thread, even if
1085 some other thread does the exec, and even if the main thread was
1086 stopped or already gone. We may still have non-leader threads of
1087 the process on our list. E.g., on targets that don't have thread
1088 exit events (like remote); or on native Linux in non-stop mode if
1089 there were only two threads in the inferior and the non-leader
1090 one is the one that execs (and nothing forces an update of the
1091 thread list up to here). When debugging remotely, it's best to
1092 avoid extra traffic, when possible, so avoid syncing the thread
1093 list with the target, and instead go ahead and delete all threads
1094 of the process but one that reported the event. Note this must
1095 be done before calling update_breakpoints_after_exec, as
1096 otherwise clearing the threads' resources would reference stale
1097 thread breakpoints -- it may have been one of these threads that
1098 stepped across the exec. We could just clear their stepping
1099 states, but as long as we're iterating, might as well delete
1100 them. Deleting them now rather than at the next user-visible
1101 stop provides a nicer sequence of events for user and MI
1103 ALL_THREADS_SAFE (th
, tmp
)
1104 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1105 delete_thread (th
->ptid
);
1107 /* We also need to clear any left over stale state for the
1108 leader/event thread. E.g., if there was any step-resume
1109 breakpoint or similar, it's gone now. We cannot truly
1110 step-to-next statement through an exec(). */
1111 th
= inferior_thread ();
1112 th
->control
.step_resume_breakpoint
= NULL
;
1113 th
->control
.exception_resume_breakpoint
= NULL
;
1114 th
->control
.single_step_breakpoints
= NULL
;
1115 th
->control
.step_range_start
= 0;
1116 th
->control
.step_range_end
= 0;
1118 /* The user may have had the main thread held stopped in the
1119 previous image (e.g., schedlock on, or non-stop). Release
1121 th
->stop_requested
= 0;
1123 update_breakpoints_after_exec ();
1125 /* What is this a.out's name? */
1126 printf_unfiltered (_("%s is executing new program: %s\n"),
1127 target_pid_to_str (inferior_ptid
),
1130 /* We've followed the inferior through an exec. Therefore, the
1131 inferior has essentially been killed & reborn. */
1133 gdb_flush (gdb_stdout
);
1135 breakpoint_init_inferior (inf_execd
);
1137 if (gdb_sysroot
!= NULL
&& *gdb_sysroot
!= '\0')
1139 char *name
= exec_file_find (execd_pathname
, NULL
);
1141 execd_pathname
= alloca (strlen (name
) + 1);
1142 strcpy (execd_pathname
, name
);
1146 /* Reset the shared library package. This ensures that we get a
1147 shlib event when the child reaches "_start", at which point the
1148 dld will have had a chance to initialize the child. */
1149 /* Also, loading a symbol file below may trigger symbol lookups, and
1150 we don't want those to be satisfied by the libraries of the
1151 previous incarnation of this process. */
1152 no_shared_libraries (NULL
, 0);
1154 if (follow_exec_mode_string
== follow_exec_mode_new
)
1156 struct program_space
*pspace
;
1158 /* The user wants to keep the old inferior and program spaces
1159 around. Create a new fresh one, and switch to it. */
1161 inf
= add_inferior (current_inferior ()->pid
);
1162 pspace
= add_program_space (maybe_new_address_space ());
1163 inf
->pspace
= pspace
;
1164 inf
->aspace
= pspace
->aspace
;
1166 exit_inferior_num_silent (current_inferior ()->num
);
1168 set_current_inferior (inf
);
1169 set_current_program_space (pspace
);
1173 /* The old description may no longer be fit for the new image.
1174 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1175 old description; we'll read a new one below. No need to do
1176 this on "follow-exec-mode new", as the old inferior stays
1177 around (its description is later cleared/refetched on
1179 target_clear_description ();
1182 gdb_assert (current_program_space
== inf
->pspace
);
1184 /* That a.out is now the one to use. */
1185 exec_file_attach (execd_pathname
, 0);
1187 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1188 (Position Independent Executable) main symbol file will get applied by
1189 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1190 the breakpoints with the zero displacement. */
1192 symbol_file_add (execd_pathname
,
1194 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
1197 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
1198 set_initial_language ();
1200 /* If the target can specify a description, read it. Must do this
1201 after flipping to the new executable (because the target supplied
1202 description must be compatible with the executable's
1203 architecture, and the old executable may e.g., be 32-bit, while
1204 the new one 64-bit), and before anything involving memory or
1206 target_find_description ();
1208 solib_create_inferior_hook (0);
1210 jit_inferior_created_hook ();
1212 breakpoint_re_set ();
1214 /* Reinsert all breakpoints. (Those which were symbolic have
1215 been reset to the proper address in the new a.out, thanks
1216 to symbol_file_command...). */
1217 insert_breakpoints ();
1219 /* The next resume of this inferior should bring it to the shlib
1220 startup breakpoints. (If the user had also set bp's on
1221 "main" from the old (parent) process, then they'll auto-
1222 matically get reset there in the new process.). */
1225 /* Info about an instruction that is being stepped over. */
1227 struct step_over_info
1229 /* If we're stepping past a breakpoint, this is the address space
1230 and address of the instruction the breakpoint is set at. We'll
1231 skip inserting all breakpoints here. Valid iff ASPACE is
1233 struct address_space
*aspace
;
1236 /* The instruction being stepped over triggers a nonsteppable
1237 watchpoint. If true, we'll skip inserting watchpoints. */
1238 int nonsteppable_watchpoint_p
;
1241 /* The step-over info of the location that is being stepped over.
1243 Note that with async/breakpoint always-inserted mode, a user might
1244 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1245 being stepped over. As setting a new breakpoint inserts all
1246 breakpoints, we need to make sure the breakpoint being stepped over
1247 isn't inserted then. We do that by only clearing the step-over
1248 info when the step-over is actually finished (or aborted).
1250 Presently GDB can only step over one breakpoint at any given time.
1251 Given threads that can't run code in the same address space as the
1252 breakpoint's can't really miss the breakpoint, GDB could be taught
1253 to step-over at most one breakpoint per address space (so this info
1254 could move to the address space object if/when GDB is extended).
1255 The set of breakpoints being stepped over will normally be much
1256 smaller than the set of all breakpoints, so a flag in the
1257 breakpoint location structure would be wasteful. A separate list
1258 also saves complexity and run-time, as otherwise we'd have to go
1259 through all breakpoint locations clearing their flag whenever we
1260 start a new sequence. Similar considerations weigh against storing
1261 this info in the thread object. Plus, not all step overs actually
1262 have breakpoint locations -- e.g., stepping past a single-step
1263 breakpoint, or stepping to complete a non-continuable
1265 static struct step_over_info step_over_info
;
1267 /* Record the address of the breakpoint/instruction we're currently
1271 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1272 int nonsteppable_watchpoint_p
)
1274 step_over_info
.aspace
= aspace
;
1275 step_over_info
.address
= address
;
1276 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1279 /* Called when we're not longer stepping over a breakpoint / an
1280 instruction, so all breakpoints are free to be (re)inserted. */
1283 clear_step_over_info (void)
1285 step_over_info
.aspace
= NULL
;
1286 step_over_info
.address
= 0;
1287 step_over_info
.nonsteppable_watchpoint_p
= 0;
1293 stepping_past_instruction_at (struct address_space
*aspace
,
1296 return (step_over_info
.aspace
!= NULL
1297 && breakpoint_address_match (aspace
, address
,
1298 step_over_info
.aspace
,
1299 step_over_info
.address
));
1305 stepping_past_nonsteppable_watchpoint (void)
1307 return step_over_info
.nonsteppable_watchpoint_p
;
1310 /* Returns true if step-over info is valid. */
1313 step_over_info_valid_p (void)
1315 return (step_over_info
.aspace
!= NULL
1316 || stepping_past_nonsteppable_watchpoint ());
1320 /* Displaced stepping. */
1322 /* In non-stop debugging mode, we must take special care to manage
1323 breakpoints properly; in particular, the traditional strategy for
1324 stepping a thread past a breakpoint it has hit is unsuitable.
1325 'Displaced stepping' is a tactic for stepping one thread past a
1326 breakpoint it has hit while ensuring that other threads running
1327 concurrently will hit the breakpoint as they should.
1329 The traditional way to step a thread T off a breakpoint in a
1330 multi-threaded program in all-stop mode is as follows:
1332 a0) Initially, all threads are stopped, and breakpoints are not
1334 a1) We single-step T, leaving breakpoints uninserted.
1335 a2) We insert breakpoints, and resume all threads.
1337 In non-stop debugging, however, this strategy is unsuitable: we
1338 don't want to have to stop all threads in the system in order to
1339 continue or step T past a breakpoint. Instead, we use displaced
1342 n0) Initially, T is stopped, other threads are running, and
1343 breakpoints are inserted.
1344 n1) We copy the instruction "under" the breakpoint to a separate
1345 location, outside the main code stream, making any adjustments
1346 to the instruction, register, and memory state as directed by
1348 n2) We single-step T over the instruction at its new location.
1349 n3) We adjust the resulting register and memory state as directed
1350 by T's architecture. This includes resetting T's PC to point
1351 back into the main instruction stream.
1354 This approach depends on the following gdbarch methods:
1356 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1357 indicate where to copy the instruction, and how much space must
1358 be reserved there. We use these in step n1.
1360 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1361 address, and makes any necessary adjustments to the instruction,
1362 register contents, and memory. We use this in step n1.
1364 - gdbarch_displaced_step_fixup adjusts registers and memory after
1365 we have successfuly single-stepped the instruction, to yield the
1366 same effect the instruction would have had if we had executed it
1367 at its original address. We use this in step n3.
1369 - gdbarch_displaced_step_free_closure provides cleanup.
1371 The gdbarch_displaced_step_copy_insn and
1372 gdbarch_displaced_step_fixup functions must be written so that
1373 copying an instruction with gdbarch_displaced_step_copy_insn,
1374 single-stepping across the copied instruction, and then applying
1375 gdbarch_displaced_insn_fixup should have the same effects on the
1376 thread's memory and registers as stepping the instruction in place
1377 would have. Exactly which responsibilities fall to the copy and
1378 which fall to the fixup is up to the author of those functions.
1380 See the comments in gdbarch.sh for details.
1382 Note that displaced stepping and software single-step cannot
1383 currently be used in combination, although with some care I think
1384 they could be made to. Software single-step works by placing
1385 breakpoints on all possible subsequent instructions; if the
1386 displaced instruction is a PC-relative jump, those breakpoints
1387 could fall in very strange places --- on pages that aren't
1388 executable, or at addresses that are not proper instruction
1389 boundaries. (We do generally let other threads run while we wait
1390 to hit the software single-step breakpoint, and they might
1391 encounter such a corrupted instruction.) One way to work around
1392 this would be to have gdbarch_displaced_step_copy_insn fully
1393 simulate the effect of PC-relative instructions (and return NULL)
1394 on architectures that use software single-stepping.
1396 In non-stop mode, we can have independent and simultaneous step
1397 requests, so more than one thread may need to simultaneously step
1398 over a breakpoint. The current implementation assumes there is
1399 only one scratch space per process. In this case, we have to
1400 serialize access to the scratch space. If thread A wants to step
1401 over a breakpoint, but we are currently waiting for some other
1402 thread to complete a displaced step, we leave thread A stopped and
1403 place it in the displaced_step_request_queue. Whenever a displaced
1404 step finishes, we pick the next thread in the queue and start a new
1405 displaced step operation on it. See displaced_step_prepare and
1406 displaced_step_fixup for details. */
1408 struct displaced_step_request
1411 struct displaced_step_request
*next
;
1414 /* Per-inferior displaced stepping state. */
1415 struct displaced_step_inferior_state
1417 /* Pointer to next in linked list. */
1418 struct displaced_step_inferior_state
*next
;
1420 /* The process this displaced step state refers to. */
1423 /* A queue of pending displaced stepping requests. One entry per
1424 thread that needs to do a displaced step. */
1425 struct displaced_step_request
*step_request_queue
;
1427 /* If this is not null_ptid, this is the thread carrying out a
1428 displaced single-step in process PID. This thread's state will
1429 require fixing up once it has completed its step. */
1432 /* The architecture the thread had when we stepped it. */
1433 struct gdbarch
*step_gdbarch
;
1435 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1436 for post-step cleanup. */
1437 struct displaced_step_closure
*step_closure
;
1439 /* The address of the original instruction, and the copy we
1441 CORE_ADDR step_original
, step_copy
;
1443 /* Saved contents of copy area. */
1444 gdb_byte
*step_saved_copy
;
1447 /* The list of states of processes involved in displaced stepping
1449 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1451 /* Get the displaced stepping state of process PID. */
1453 static struct displaced_step_inferior_state
*
1454 get_displaced_stepping_state (int pid
)
1456 struct displaced_step_inferior_state
*state
;
1458 for (state
= displaced_step_inferior_states
;
1460 state
= state
->next
)
1461 if (state
->pid
== pid
)
1467 /* Return true if process PID has a thread doing a displaced step. */
1470 displaced_step_in_progress (int pid
)
1472 struct displaced_step_inferior_state
*displaced
;
1474 displaced
= get_displaced_stepping_state (pid
);
1475 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1481 /* Add a new displaced stepping state for process PID to the displaced
1482 stepping state list, or return a pointer to an already existing
1483 entry, if it already exists. Never returns NULL. */
1485 static struct displaced_step_inferior_state
*
1486 add_displaced_stepping_state (int pid
)
1488 struct displaced_step_inferior_state
*state
;
1490 for (state
= displaced_step_inferior_states
;
1492 state
= state
->next
)
1493 if (state
->pid
== pid
)
1496 state
= xcalloc (1, sizeof (*state
));
1498 state
->next
= displaced_step_inferior_states
;
1499 displaced_step_inferior_states
= state
;
1504 /* If inferior is in displaced stepping, and ADDR equals to starting address
1505 of copy area, return corresponding displaced_step_closure. Otherwise,
1508 struct displaced_step_closure
*
1509 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1511 struct displaced_step_inferior_state
*displaced
1512 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1514 /* If checking the mode of displaced instruction in copy area. */
1515 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1516 && (displaced
->step_copy
== addr
))
1517 return displaced
->step_closure
;
1522 /* Remove the displaced stepping state of process PID. */
1525 remove_displaced_stepping_state (int pid
)
1527 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1529 gdb_assert (pid
!= 0);
1531 it
= displaced_step_inferior_states
;
1532 prev_next_p
= &displaced_step_inferior_states
;
1537 *prev_next_p
= it
->next
;
1542 prev_next_p
= &it
->next
;
1548 infrun_inferior_exit (struct inferior
*inf
)
1550 remove_displaced_stepping_state (inf
->pid
);
1553 /* If ON, and the architecture supports it, GDB will use displaced
1554 stepping to step over breakpoints. If OFF, or if the architecture
1555 doesn't support it, GDB will instead use the traditional
1556 hold-and-step approach. If AUTO (which is the default), GDB will
1557 decide which technique to use to step over breakpoints depending on
1558 which of all-stop or non-stop mode is active --- displaced stepping
1559 in non-stop mode; hold-and-step in all-stop mode. */
1561 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1564 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1565 struct cmd_list_element
*c
,
1568 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1569 fprintf_filtered (file
,
1570 _("Debugger's willingness to use displaced stepping "
1571 "to step over breakpoints is %s (currently %s).\n"),
1572 value
, non_stop
? "on" : "off");
1574 fprintf_filtered (file
,
1575 _("Debugger's willingness to use displaced stepping "
1576 "to step over breakpoints is %s.\n"), value
);
1579 /* Return non-zero if displaced stepping can/should be used to step
1580 over breakpoints. */
1583 use_displaced_stepping (struct gdbarch
*gdbarch
)
1585 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
&& non_stop
)
1586 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1587 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1588 && find_record_target () == NULL
);
1591 /* Clean out any stray displaced stepping state. */
1593 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1595 /* Indicate that there is no cleanup pending. */
1596 displaced
->step_ptid
= null_ptid
;
1598 if (displaced
->step_closure
)
1600 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1601 displaced
->step_closure
);
1602 displaced
->step_closure
= NULL
;
1607 displaced_step_clear_cleanup (void *arg
)
1609 struct displaced_step_inferior_state
*state
= arg
;
1611 displaced_step_clear (state
);
1614 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1616 displaced_step_dump_bytes (struct ui_file
*file
,
1617 const gdb_byte
*buf
,
1622 for (i
= 0; i
< len
; i
++)
1623 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1624 fputs_unfiltered ("\n", file
);
1627 /* Prepare to single-step, using displaced stepping.
1629 Note that we cannot use displaced stepping when we have a signal to
1630 deliver. If we have a signal to deliver and an instruction to step
1631 over, then after the step, there will be no indication from the
1632 target whether the thread entered a signal handler or ignored the
1633 signal and stepped over the instruction successfully --- both cases
1634 result in a simple SIGTRAP. In the first case we mustn't do a
1635 fixup, and in the second case we must --- but we can't tell which.
1636 Comments in the code for 'random signals' in handle_inferior_event
1637 explain how we handle this case instead.
1639 Returns 1 if preparing was successful -- this thread is going to be
1640 stepped now; or 0 if displaced stepping this thread got queued. */
1642 displaced_step_prepare (ptid_t ptid
)
1644 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1645 struct thread_info
*tp
= find_thread_ptid (ptid
);
1646 struct regcache
*regcache
= get_thread_regcache (ptid
);
1647 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1648 CORE_ADDR original
, copy
;
1650 struct displaced_step_closure
*closure
;
1651 struct displaced_step_inferior_state
*displaced
;
1654 /* We should never reach this function if the architecture does not
1655 support displaced stepping. */
1656 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1658 /* Disable range stepping while executing in the scratch pad. We
1659 want a single-step even if executing the displaced instruction in
1660 the scratch buffer lands within the stepping range (e.g., a
1662 tp
->control
.may_range_step
= 0;
1664 /* We have to displaced step one thread at a time, as we only have
1665 access to a single scratch space per inferior. */
1667 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1669 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1671 /* Already waiting for a displaced step to finish. Defer this
1672 request and place in queue. */
1673 struct displaced_step_request
*req
, *new_req
;
1675 if (debug_displaced
)
1676 fprintf_unfiltered (gdb_stdlog
,
1677 "displaced: defering step of %s\n",
1678 target_pid_to_str (ptid
));
1680 new_req
= xmalloc (sizeof (*new_req
));
1681 new_req
->ptid
= ptid
;
1682 new_req
->next
= NULL
;
1684 if (displaced
->step_request_queue
)
1686 for (req
= displaced
->step_request_queue
;
1690 req
->next
= new_req
;
1693 displaced
->step_request_queue
= new_req
;
1699 if (debug_displaced
)
1700 fprintf_unfiltered (gdb_stdlog
,
1701 "displaced: stepping %s now\n",
1702 target_pid_to_str (ptid
));
1705 displaced_step_clear (displaced
);
1707 old_cleanups
= save_inferior_ptid ();
1708 inferior_ptid
= ptid
;
1710 original
= regcache_read_pc (regcache
);
1712 copy
= gdbarch_displaced_step_location (gdbarch
);
1713 len
= gdbarch_max_insn_length (gdbarch
);
1715 /* Save the original contents of the copy area. */
1716 displaced
->step_saved_copy
= xmalloc (len
);
1717 ignore_cleanups
= make_cleanup (free_current_contents
,
1718 &displaced
->step_saved_copy
);
1719 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1721 throw_error (MEMORY_ERROR
,
1722 _("Error accessing memory address %s (%s) for "
1723 "displaced-stepping scratch space."),
1724 paddress (gdbarch
, copy
), safe_strerror (status
));
1725 if (debug_displaced
)
1727 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1728 paddress (gdbarch
, copy
));
1729 displaced_step_dump_bytes (gdb_stdlog
,
1730 displaced
->step_saved_copy
,
1734 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1735 original
, copy
, regcache
);
1737 /* We don't support the fully-simulated case at present. */
1738 gdb_assert (closure
);
1740 /* Save the information we need to fix things up if the step
1742 displaced
->step_ptid
= ptid
;
1743 displaced
->step_gdbarch
= gdbarch
;
1744 displaced
->step_closure
= closure
;
1745 displaced
->step_original
= original
;
1746 displaced
->step_copy
= copy
;
1748 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1750 /* Resume execution at the copy. */
1751 regcache_write_pc (regcache
, copy
);
1753 discard_cleanups (ignore_cleanups
);
1755 do_cleanups (old_cleanups
);
1757 if (debug_displaced
)
1758 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1759 paddress (gdbarch
, copy
));
1765 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1766 const gdb_byte
*myaddr
, int len
)
1768 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1770 inferior_ptid
= ptid
;
1771 write_memory (memaddr
, myaddr
, len
);
1772 do_cleanups (ptid_cleanup
);
1775 /* Restore the contents of the copy area for thread PTID. */
1778 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1781 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1783 write_memory_ptid (ptid
, displaced
->step_copy
,
1784 displaced
->step_saved_copy
, len
);
1785 if (debug_displaced
)
1786 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1787 target_pid_to_str (ptid
),
1788 paddress (displaced
->step_gdbarch
,
1789 displaced
->step_copy
));
1793 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1795 struct cleanup
*old_cleanups
;
1796 struct displaced_step_inferior_state
*displaced
1797 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1799 /* Was any thread of this process doing a displaced step? */
1800 if (displaced
== NULL
)
1803 /* Was this event for the pid we displaced? */
1804 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1805 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1808 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1810 displaced_step_restore (displaced
, displaced
->step_ptid
);
1812 /* Fixup may need to read memory/registers. Switch to the thread
1813 that we're fixing up. Also, target_stopped_by_watchpoint checks
1814 the current thread. */
1815 switch_to_thread (event_ptid
);
1817 /* Did the instruction complete successfully? */
1818 if (signal
== GDB_SIGNAL_TRAP
1819 && !(target_stopped_by_watchpoint ()
1820 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1821 || target_have_steppable_watchpoint
)))
1823 /* Fix up the resulting state. */
1824 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1825 displaced
->step_closure
,
1826 displaced
->step_original
,
1827 displaced
->step_copy
,
1828 get_thread_regcache (displaced
->step_ptid
));
1832 /* Since the instruction didn't complete, all we can do is
1834 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1835 CORE_ADDR pc
= regcache_read_pc (regcache
);
1837 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1838 regcache_write_pc (regcache
, pc
);
1841 do_cleanups (old_cleanups
);
1843 displaced
->step_ptid
= null_ptid
;
1845 /* Are there any pending displaced stepping requests? If so, run
1846 one now. Leave the state object around, since we're likely to
1847 need it again soon. */
1848 while (displaced
->step_request_queue
)
1850 struct displaced_step_request
*head
;
1852 struct regcache
*regcache
;
1853 struct gdbarch
*gdbarch
;
1854 CORE_ADDR actual_pc
;
1855 struct address_space
*aspace
;
1857 head
= displaced
->step_request_queue
;
1859 displaced
->step_request_queue
= head
->next
;
1862 context_switch (ptid
);
1864 regcache
= get_thread_regcache (ptid
);
1865 actual_pc
= regcache_read_pc (regcache
);
1866 aspace
= get_regcache_aspace (regcache
);
1867 gdbarch
= get_regcache_arch (regcache
);
1869 if (breakpoint_here_p (aspace
, actual_pc
))
1871 if (debug_displaced
)
1872 fprintf_unfiltered (gdb_stdlog
,
1873 "displaced: stepping queued %s now\n",
1874 target_pid_to_str (ptid
));
1876 displaced_step_prepare (ptid
);
1878 if (debug_displaced
)
1880 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1883 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1884 paddress (gdbarch
, actual_pc
));
1885 read_memory (actual_pc
, buf
, sizeof (buf
));
1886 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1889 if (gdbarch_displaced_step_hw_singlestep (gdbarch
,
1890 displaced
->step_closure
))
1891 target_resume (ptid
, 1, GDB_SIGNAL_0
);
1893 target_resume (ptid
, 0, GDB_SIGNAL_0
);
1895 /* Done, we're stepping a thread. */
1901 struct thread_info
*tp
= inferior_thread ();
1903 /* The breakpoint we were sitting under has since been
1905 tp
->control
.trap_expected
= 0;
1907 /* Go back to what we were trying to do. */
1908 step
= currently_stepping (tp
);
1911 step
= maybe_software_singlestep (gdbarch
, actual_pc
);
1913 if (debug_displaced
)
1914 fprintf_unfiltered (gdb_stdlog
,
1915 "displaced: breakpoint is gone: %s, step(%d)\n",
1916 target_pid_to_str (tp
->ptid
), step
);
1918 target_resume (ptid
, step
, GDB_SIGNAL_0
);
1919 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1921 /* This request was discarded. See if there's any other
1922 thread waiting for its turn. */
1927 /* Update global variables holding ptids to hold NEW_PTID if they were
1928 holding OLD_PTID. */
1930 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1932 struct displaced_step_request
*it
;
1933 struct displaced_step_inferior_state
*displaced
;
1935 if (ptid_equal (inferior_ptid
, old_ptid
))
1936 inferior_ptid
= new_ptid
;
1938 for (displaced
= displaced_step_inferior_states
;
1940 displaced
= displaced
->next
)
1942 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
1943 displaced
->step_ptid
= new_ptid
;
1945 for (it
= displaced
->step_request_queue
; it
; it
= it
->next
)
1946 if (ptid_equal (it
->ptid
, old_ptid
))
1947 it
->ptid
= new_ptid
;
1954 /* Things to clean up if we QUIT out of resume (). */
1956 resume_cleanups (void *ignore
)
1958 if (!ptid_equal (inferior_ptid
, null_ptid
))
1959 delete_single_step_breakpoints (inferior_thread ());
1964 static const char schedlock_off
[] = "off";
1965 static const char schedlock_on
[] = "on";
1966 static const char schedlock_step
[] = "step";
1967 static const char *const scheduler_enums
[] = {
1973 static const char *scheduler_mode
= schedlock_off
;
1975 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1976 struct cmd_list_element
*c
, const char *value
)
1978 fprintf_filtered (file
,
1979 _("Mode for locking scheduler "
1980 "during execution is \"%s\".\n"),
1985 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1987 if (!target_can_lock_scheduler
)
1989 scheduler_mode
= schedlock_off
;
1990 error (_("Target '%s' cannot support this command."), target_shortname
);
1994 /* True if execution commands resume all threads of all processes by
1995 default; otherwise, resume only threads of the current inferior
1997 int sched_multi
= 0;
1999 /* Try to setup for software single stepping over the specified location.
2000 Return 1 if target_resume() should use hardware single step.
2002 GDBARCH the current gdbarch.
2003 PC the location to step over. */
2006 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2010 if (execution_direction
== EXEC_FORWARD
2011 && gdbarch_software_single_step_p (gdbarch
)
2012 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
2022 user_visible_resume_ptid (int step
)
2028 /* With non-stop mode on, threads are always handled
2030 resume_ptid
= inferior_ptid
;
2032 else if ((scheduler_mode
== schedlock_on
)
2033 || (scheduler_mode
== schedlock_step
&& step
))
2035 /* User-settable 'scheduler' mode requires solo thread
2037 resume_ptid
= inferior_ptid
;
2039 else if (!sched_multi
&& target_supports_multi_process ())
2041 /* Resume all threads of the current process (and none of other
2043 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2047 /* Resume all threads of all processes. */
2048 resume_ptid
= RESUME_ALL
;
2054 /* Wrapper for target_resume, that handles infrun-specific
2058 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2060 struct thread_info
*tp
= inferior_thread ();
2062 /* Install inferior's terminal modes. */
2063 target_terminal_inferior ();
2065 /* Avoid confusing the next resume, if the next stop/resume
2066 happens to apply to another thread. */
2067 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2069 /* Advise target which signals may be handled silently.
2071 If we have removed breakpoints because we are stepping over one
2072 in-line (in any thread), we need to receive all signals to avoid
2073 accidentally skipping a breakpoint during execution of a signal
2076 Likewise if we're displaced stepping, otherwise a trap for a
2077 breakpoint in a signal handler might be confused with the
2078 displaced step finishing. We don't make the displaced_step_fixup
2079 step distinguish the cases instead, because:
2081 - a backtrace while stopped in the signal handler would show the
2082 scratch pad as frame older than the signal handler, instead of
2083 the real mainline code.
2085 - when the thread is later resumed, the signal handler would
2086 return to the scratch pad area, which would no longer be
2088 if (step_over_info_valid_p ()
2089 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2090 target_pass_signals (0, NULL
);
2092 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2094 target_resume (resume_ptid
, step
, sig
);
2097 /* Resume the inferior, but allow a QUIT. This is useful if the user
2098 wants to interrupt some lengthy single-stepping operation
2099 (for child processes, the SIGINT goes to the inferior, and so
2100 we get a SIGINT random_signal, but for remote debugging and perhaps
2101 other targets, that's not true).
2103 SIG is the signal to give the inferior (zero for none). */
2105 resume (enum gdb_signal sig
)
2107 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2108 struct regcache
*regcache
= get_current_regcache ();
2109 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2110 struct thread_info
*tp
= inferior_thread ();
2111 CORE_ADDR pc
= regcache_read_pc (regcache
);
2112 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2114 /* This represents the user's step vs continue request. When
2115 deciding whether "set scheduler-locking step" applies, it's the
2116 user's intention that counts. */
2117 const int user_step
= tp
->control
.stepping_command
;
2118 /* This represents what we'll actually request the target to do.
2119 This can decay from a step to a continue, if e.g., we need to
2120 implement single-stepping with breakpoints (software
2124 tp
->stepped_breakpoint
= 0;
2128 /* Depends on stepped_breakpoint. */
2129 step
= currently_stepping (tp
);
2131 if (current_inferior ()->waiting_for_vfork_done
)
2133 /* Don't try to single-step a vfork parent that is waiting for
2134 the child to get out of the shared memory region (by exec'ing
2135 or exiting). This is particularly important on software
2136 single-step archs, as the child process would trip on the
2137 software single step breakpoint inserted for the parent
2138 process. Since the parent will not actually execute any
2139 instruction until the child is out of the shared region (such
2140 are vfork's semantics), it is safe to simply continue it.
2141 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2142 the parent, and tell it to `keep_going', which automatically
2143 re-sets it stepping. */
2145 fprintf_unfiltered (gdb_stdlog
,
2146 "infrun: resume : clear step\n");
2151 fprintf_unfiltered (gdb_stdlog
,
2152 "infrun: resume (step=%d, signal=%s), "
2153 "trap_expected=%d, current thread [%s] at %s\n",
2154 step
, gdb_signal_to_symbol_string (sig
),
2155 tp
->control
.trap_expected
,
2156 target_pid_to_str (inferior_ptid
),
2157 paddress (gdbarch
, pc
));
2159 /* Normally, by the time we reach `resume', the breakpoints are either
2160 removed or inserted, as appropriate. The exception is if we're sitting
2161 at a permanent breakpoint; we need to step over it, but permanent
2162 breakpoints can't be removed. So we have to test for it here. */
2163 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2165 if (sig
!= GDB_SIGNAL_0
)
2167 /* We have a signal to pass to the inferior. The resume
2168 may, or may not take us to the signal handler. If this
2169 is a step, we'll need to stop in the signal handler, if
2170 there's one, (if the target supports stepping into
2171 handlers), or in the next mainline instruction, if
2172 there's no handler. If this is a continue, we need to be
2173 sure to run the handler with all breakpoints inserted.
2174 In all cases, set a breakpoint at the current address
2175 (where the handler returns to), and once that breakpoint
2176 is hit, resume skipping the permanent breakpoint. If
2177 that breakpoint isn't hit, then we've stepped into the
2178 signal handler (or hit some other event). We'll delete
2179 the step-resume breakpoint then. */
2182 fprintf_unfiltered (gdb_stdlog
,
2183 "infrun: resume: skipping permanent breakpoint, "
2184 "deliver signal first\n");
2186 clear_step_over_info ();
2187 tp
->control
.trap_expected
= 0;
2189 if (tp
->control
.step_resume_breakpoint
== NULL
)
2191 /* Set a "high-priority" step-resume, as we don't want
2192 user breakpoints at PC to trigger (again) when this
2194 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2195 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2197 tp
->step_after_step_resume_breakpoint
= step
;
2200 insert_breakpoints ();
2204 /* There's no signal to pass, we can go ahead and skip the
2205 permanent breakpoint manually. */
2207 fprintf_unfiltered (gdb_stdlog
,
2208 "infrun: resume: skipping permanent breakpoint\n");
2209 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2210 /* Update pc to reflect the new address from which we will
2211 execute instructions. */
2212 pc
= regcache_read_pc (regcache
);
2216 /* We've already advanced the PC, so the stepping part
2217 is done. Now we need to arrange for a trap to be
2218 reported to handle_inferior_event. Set a breakpoint
2219 at the current PC, and run to it. Don't update
2220 prev_pc, because if we end in
2221 switch_back_to_stepped_thread, we want the "expected
2222 thread advanced also" branch to be taken. IOW, we
2223 don't want this thread to step further from PC
2225 gdb_assert (!step_over_info_valid_p ());
2226 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2227 insert_breakpoints ();
2229 resume_ptid
= user_visible_resume_ptid (user_step
);
2230 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2231 discard_cleanups (old_cleanups
);
2237 /* If we have a breakpoint to step over, make sure to do a single
2238 step only. Same if we have software watchpoints. */
2239 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2240 tp
->control
.may_range_step
= 0;
2242 /* If enabled, step over breakpoints by executing a copy of the
2243 instruction at a different address.
2245 We can't use displaced stepping when we have a signal to deliver;
2246 the comments for displaced_step_prepare explain why. The
2247 comments in the handle_inferior event for dealing with 'random
2248 signals' explain what we do instead.
2250 We can't use displaced stepping when we are waiting for vfork_done
2251 event, displaced stepping breaks the vfork child similarly as single
2252 step software breakpoint. */
2253 if (use_displaced_stepping (gdbarch
)
2254 && tp
->control
.trap_expected
2255 && !step_over_info_valid_p ()
2256 && sig
== GDB_SIGNAL_0
2257 && !current_inferior ()->waiting_for_vfork_done
)
2259 struct displaced_step_inferior_state
*displaced
;
2261 if (!displaced_step_prepare (inferior_ptid
))
2263 /* Got placed in displaced stepping queue. Will be resumed
2264 later when all the currently queued displaced stepping
2265 requests finish. The thread is not executing at this
2266 point, and the call to set_executing will be made later.
2267 But we need to call set_running here, since from the
2268 user/frontend's point of view, threads were set running.
2269 Unless we're calling an inferior function, as in that
2270 case we pretend the inferior doesn't run at all. */
2271 if (!tp
->control
.in_infcall
)
2272 set_running (user_visible_resume_ptid (user_step
), 1);
2273 discard_cleanups (old_cleanups
);
2277 /* Update pc to reflect the new address from which we will execute
2278 instructions due to displaced stepping. */
2279 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2281 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2282 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2283 displaced
->step_closure
);
2286 /* Do we need to do it the hard way, w/temp breakpoints? */
2288 step
= maybe_software_singlestep (gdbarch
, pc
);
2290 /* Currently, our software single-step implementation leads to different
2291 results than hardware single-stepping in one situation: when stepping
2292 into delivering a signal which has an associated signal handler,
2293 hardware single-step will stop at the first instruction of the handler,
2294 while software single-step will simply skip execution of the handler.
2296 For now, this difference in behavior is accepted since there is no
2297 easy way to actually implement single-stepping into a signal handler
2298 without kernel support.
2300 However, there is one scenario where this difference leads to follow-on
2301 problems: if we're stepping off a breakpoint by removing all breakpoints
2302 and then single-stepping. In this case, the software single-step
2303 behavior means that even if there is a *breakpoint* in the signal
2304 handler, GDB still would not stop.
2306 Fortunately, we can at least fix this particular issue. We detect
2307 here the case where we are about to deliver a signal while software
2308 single-stepping with breakpoints removed. In this situation, we
2309 revert the decisions to remove all breakpoints and insert single-
2310 step breakpoints, and instead we install a step-resume breakpoint
2311 at the current address, deliver the signal without stepping, and
2312 once we arrive back at the step-resume breakpoint, actually step
2313 over the breakpoint we originally wanted to step over. */
2314 if (thread_has_single_step_breakpoints_set (tp
)
2315 && sig
!= GDB_SIGNAL_0
2316 && step_over_info_valid_p ())
2318 /* If we have nested signals or a pending signal is delivered
2319 immediately after a handler returns, might might already have
2320 a step-resume breakpoint set on the earlier handler. We cannot
2321 set another step-resume breakpoint; just continue on until the
2322 original breakpoint is hit. */
2323 if (tp
->control
.step_resume_breakpoint
== NULL
)
2325 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2326 tp
->step_after_step_resume_breakpoint
= 1;
2329 delete_single_step_breakpoints (tp
);
2331 clear_step_over_info ();
2332 tp
->control
.trap_expected
= 0;
2334 insert_breakpoints ();
2337 /* If STEP is set, it's a request to use hardware stepping
2338 facilities. But in that case, we should never
2339 use singlestep breakpoint. */
2340 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2342 /* Decide the set of threads to ask the target to resume. Start
2343 by assuming everything will be resumed, than narrow the set
2344 by applying increasingly restricting conditions. */
2345 resume_ptid
= user_visible_resume_ptid (user_step
);
2347 /* Even if RESUME_PTID is a wildcard, and we end up resuming less
2348 (e.g., we might need to step over a breakpoint), from the
2349 user/frontend's point of view, all threads in RESUME_PTID are now
2350 running. Unless we're calling an inferior function, as in that
2351 case pretend we inferior doesn't run at all. */
2352 if (!tp
->control
.in_infcall
)
2353 set_running (resume_ptid
, 1);
2355 /* Maybe resume a single thread after all. */
2356 if ((step
|| thread_has_single_step_breakpoints_set (tp
))
2357 && tp
->control
.trap_expected
)
2359 /* We're allowing a thread to run past a breakpoint it has
2360 hit, by single-stepping the thread with the breakpoint
2361 removed. In which case, we need to single-step only this
2362 thread, and keep others stopped, as they can miss this
2363 breakpoint if allowed to run. */
2364 resume_ptid
= inferior_ptid
;
2367 if (execution_direction
!= EXEC_REVERSE
2368 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2370 /* The only case we currently need to step a breakpoint
2371 instruction is when we have a signal to deliver. See
2372 handle_signal_stop where we handle random signals that could
2373 take out us out of the stepping range. Normally, in that
2374 case we end up continuing (instead of stepping) over the
2375 signal handler with a breakpoint at PC, but there are cases
2376 where we should _always_ single-step, even if we have a
2377 step-resume breakpoint, like when a software watchpoint is
2378 set. Assuming single-stepping and delivering a signal at the
2379 same time would takes us to the signal handler, then we could
2380 have removed the breakpoint at PC to step over it. However,
2381 some hardware step targets (like e.g., Mac OS) can't step
2382 into signal handlers, and for those, we need to leave the
2383 breakpoint at PC inserted, as otherwise if the handler
2384 recurses and executes PC again, it'll miss the breakpoint.
2385 So we leave the breakpoint inserted anyway, but we need to
2386 record that we tried to step a breakpoint instruction, so
2387 that adjust_pc_after_break doesn't end up confused. */
2388 gdb_assert (sig
!= GDB_SIGNAL_0
);
2390 tp
->stepped_breakpoint
= 1;
2392 /* Most targets can step a breakpoint instruction, thus
2393 executing it normally. But if this one cannot, just
2394 continue and we will hit it anyway. */
2395 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2400 && use_displaced_stepping (gdbarch
)
2401 && tp
->control
.trap_expected
2402 && !step_over_info_valid_p ())
2404 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2405 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2406 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2409 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2410 paddress (resume_gdbarch
, actual_pc
));
2411 read_memory (actual_pc
, buf
, sizeof (buf
));
2412 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2415 if (tp
->control
.may_range_step
)
2417 /* If we're resuming a thread with the PC out of the step
2418 range, then we're doing some nested/finer run control
2419 operation, like stepping the thread out of the dynamic
2420 linker or the displaced stepping scratch pad. We
2421 shouldn't have allowed a range step then. */
2422 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2425 do_target_resume (resume_ptid
, step
, sig
);
2426 discard_cleanups (old_cleanups
);
2431 /* Clear out all variables saying what to do when inferior is continued.
2432 First do this, then set the ones you want, then call `proceed'. */
2435 clear_proceed_status_thread (struct thread_info
*tp
)
2438 fprintf_unfiltered (gdb_stdlog
,
2439 "infrun: clear_proceed_status_thread (%s)\n",
2440 target_pid_to_str (tp
->ptid
));
2442 /* If this signal should not be seen by program, give it zero.
2443 Used for debugging signals. */
2444 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2445 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2447 tp
->control
.trap_expected
= 0;
2448 tp
->control
.step_range_start
= 0;
2449 tp
->control
.step_range_end
= 0;
2450 tp
->control
.may_range_step
= 0;
2451 tp
->control
.step_frame_id
= null_frame_id
;
2452 tp
->control
.step_stack_frame_id
= null_frame_id
;
2453 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2454 tp
->control
.step_start_function
= NULL
;
2455 tp
->stop_requested
= 0;
2457 tp
->control
.stop_step
= 0;
2459 tp
->control
.proceed_to_finish
= 0;
2461 tp
->control
.command_interp
= NULL
;
2462 tp
->control
.stepping_command
= 0;
2464 /* Discard any remaining commands or status from previous stop. */
2465 bpstat_clear (&tp
->control
.stop_bpstat
);
2469 clear_proceed_status (int step
)
2473 struct thread_info
*tp
;
2476 resume_ptid
= user_visible_resume_ptid (step
);
2478 /* In all-stop mode, delete the per-thread status of all threads
2479 we're about to resume, implicitly and explicitly. */
2480 ALL_NON_EXITED_THREADS (tp
)
2482 if (!ptid_match (tp
->ptid
, resume_ptid
))
2484 clear_proceed_status_thread (tp
);
2488 if (!ptid_equal (inferior_ptid
, null_ptid
))
2490 struct inferior
*inferior
;
2494 /* If in non-stop mode, only delete the per-thread status of
2495 the current thread. */
2496 clear_proceed_status_thread (inferior_thread ());
2499 inferior
= current_inferior ();
2500 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2503 stop_after_trap
= 0;
2505 clear_step_over_info ();
2507 observer_notify_about_to_proceed ();
2511 regcache_xfree (stop_registers
);
2512 stop_registers
= NULL
;
2516 /* Returns true if TP is still stopped at a breakpoint that needs
2517 stepping-over in order to make progress. If the breakpoint is gone
2518 meanwhile, we can skip the whole step-over dance. */
2521 thread_still_needs_step_over (struct thread_info
*tp
)
2523 if (tp
->stepping_over_breakpoint
)
2525 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2527 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2528 regcache_read_pc (regcache
))
2529 == ordinary_breakpoint_here
)
2532 tp
->stepping_over_breakpoint
= 0;
2538 /* Returns true if scheduler locking applies. STEP indicates whether
2539 we're about to do a step/next-like command to a thread. */
2542 schedlock_applies (struct thread_info
*tp
)
2544 return (scheduler_mode
== schedlock_on
2545 || (scheduler_mode
== schedlock_step
2546 && tp
->control
.stepping_command
));
2549 /* Look a thread other than EXCEPT that has previously reported a
2550 breakpoint event, and thus needs a step-over in order to make
2551 progress. Returns NULL is none is found. */
2553 static struct thread_info
*
2554 find_thread_needs_step_over (struct thread_info
*except
)
2556 struct thread_info
*tp
, *current
;
2558 /* With non-stop mode on, threads are always handled individually. */
2559 gdb_assert (! non_stop
);
2561 current
= inferior_thread ();
2563 /* If scheduler locking applies, we can avoid iterating over all
2565 if (schedlock_applies (except
))
2567 if (except
!= current
2568 && thread_still_needs_step_over (current
))
2574 ALL_NON_EXITED_THREADS (tp
)
2576 /* Ignore the EXCEPT thread. */
2579 /* Ignore threads of processes we're not resuming. */
2581 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
2584 if (thread_still_needs_step_over (tp
))
2591 /* Basic routine for continuing the program in various fashions.
2593 ADDR is the address to resume at, or -1 for resume where stopped.
2594 SIGGNAL is the signal to give it, or 0 for none,
2595 or -1 for act according to how it stopped.
2596 STEP is nonzero if should trap after one instruction.
2597 -1 means return after that and print nothing.
2598 You should probably set various step_... variables
2599 before calling here, if you are stepping.
2601 You should call clear_proceed_status before calling proceed. */
2604 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2606 struct regcache
*regcache
;
2607 struct gdbarch
*gdbarch
;
2608 struct thread_info
*tp
;
2610 struct address_space
*aspace
;
2612 /* If we're stopped at a fork/vfork, follow the branch set by the
2613 "set follow-fork-mode" command; otherwise, we'll just proceed
2614 resuming the current thread. */
2615 if (!follow_fork ())
2617 /* The target for some reason decided not to resume. */
2619 if (target_can_async_p ())
2620 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2624 /* We'll update this if & when we switch to a new thread. */
2625 previous_inferior_ptid
= inferior_ptid
;
2627 regcache
= get_current_regcache ();
2628 gdbarch
= get_regcache_arch (regcache
);
2629 aspace
= get_regcache_aspace (regcache
);
2630 pc
= regcache_read_pc (regcache
);
2631 tp
= inferior_thread ();
2633 /* Fill in with reasonable starting values. */
2634 init_thread_stepping_state (tp
);
2636 if (addr
== (CORE_ADDR
) -1)
2639 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
2640 && execution_direction
!= EXEC_REVERSE
)
2641 /* There is a breakpoint at the address we will resume at,
2642 step one instruction before inserting breakpoints so that
2643 we do not stop right away (and report a second hit at this
2646 Note, we don't do this in reverse, because we won't
2647 actually be executing the breakpoint insn anyway.
2648 We'll be (un-)executing the previous instruction. */
2649 tp
->stepping_over_breakpoint
= 1;
2650 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2651 && gdbarch_single_step_through_delay (gdbarch
,
2652 get_current_frame ()))
2653 /* We stepped onto an instruction that needs to be stepped
2654 again before re-inserting the breakpoint, do so. */
2655 tp
->stepping_over_breakpoint
= 1;
2659 regcache_write_pc (regcache
, addr
);
2662 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2663 tp
->suspend
.stop_signal
= siggnal
;
2665 /* Record the interpreter that issued the execution command that
2666 caused this thread to resume. If the top level interpreter is
2667 MI/async, and the execution command was a CLI command
2668 (next/step/etc.), we'll want to print stop event output to the MI
2669 console channel (the stepped-to line, etc.), as if the user
2670 entered the execution command on a real GDB console. */
2671 inferior_thread ()->control
.command_interp
= command_interp ();
2674 fprintf_unfiltered (gdb_stdlog
,
2675 "infrun: proceed (addr=%s, signal=%s)\n",
2676 paddress (gdbarch
, addr
),
2677 gdb_signal_to_symbol_string (siggnal
));
2680 /* In non-stop, each thread is handled individually. The context
2681 must already be set to the right thread here. */
2685 struct thread_info
*step_over
;
2687 /* In a multi-threaded task we may select another thread and
2688 then continue or step.
2690 But if the old thread was stopped at a breakpoint, it will
2691 immediately cause another breakpoint stop without any
2692 execution (i.e. it will report a breakpoint hit incorrectly).
2693 So we must step over it first.
2695 Look for a thread other than the current (TP) that reported a
2696 breakpoint hit and hasn't been resumed yet since. */
2697 step_over
= find_thread_needs_step_over (tp
);
2698 if (step_over
!= NULL
)
2701 fprintf_unfiltered (gdb_stdlog
,
2702 "infrun: need to step-over [%s] first\n",
2703 target_pid_to_str (step_over
->ptid
));
2705 /* Store the prev_pc for the stepping thread too, needed by
2706 switch_back_to_stepped_thread. */
2707 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2708 switch_to_thread (step_over
->ptid
);
2713 /* If we need to step over a breakpoint, and we're not using
2714 displaced stepping to do so, insert all breakpoints (watchpoints,
2715 etc.) but the one we're stepping over, step one instruction, and
2716 then re-insert the breakpoint when that step is finished. */
2717 if (tp
->stepping_over_breakpoint
&& !use_displaced_stepping (gdbarch
))
2719 struct regcache
*regcache
= get_current_regcache ();
2721 set_step_over_info (get_regcache_aspace (regcache
),
2722 regcache_read_pc (regcache
), 0);
2725 clear_step_over_info ();
2727 insert_breakpoints ();
2729 tp
->control
.trap_expected
= tp
->stepping_over_breakpoint
;
2731 annotate_starting ();
2733 /* Make sure that output from GDB appears before output from the
2735 gdb_flush (gdb_stdout
);
2737 /* Refresh prev_pc value just prior to resuming. This used to be
2738 done in stop_waiting, however, setting prev_pc there did not handle
2739 scenarios such as inferior function calls or returning from
2740 a function via the return command. In those cases, the prev_pc
2741 value was not set properly for subsequent commands. The prev_pc value
2742 is used to initialize the starting line number in the ecs. With an
2743 invalid value, the gdb next command ends up stopping at the position
2744 represented by the next line table entry past our start position.
2745 On platforms that generate one line table entry per line, this
2746 is not a problem. However, on the ia64, the compiler generates
2747 extraneous line table entries that do not increase the line number.
2748 When we issue the gdb next command on the ia64 after an inferior call
2749 or a return command, we often end up a few instructions forward, still
2750 within the original line we started.
2752 An attempt was made to refresh the prev_pc at the same time the
2753 execution_control_state is initialized (for instance, just before
2754 waiting for an inferior event). But this approach did not work
2755 because of platforms that use ptrace, where the pc register cannot
2756 be read unless the inferior is stopped. At that point, we are not
2757 guaranteed the inferior is stopped and so the regcache_read_pc() call
2758 can fail. Setting the prev_pc value here ensures the value is updated
2759 correctly when the inferior is stopped. */
2760 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2762 /* Resume inferior. */
2763 resume (tp
->suspend
.stop_signal
);
2765 /* Wait for it to stop (if not standalone)
2766 and in any case decode why it stopped, and act accordingly. */
2767 /* Do this only if we are not using the event loop, or if the target
2768 does not support asynchronous execution. */
2769 if (!target_can_async_p ())
2771 wait_for_inferior ();
2777 /* Start remote-debugging of a machine over a serial link. */
2780 start_remote (int from_tty
)
2782 struct inferior
*inferior
;
2784 inferior
= current_inferior ();
2785 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2787 /* Always go on waiting for the target, regardless of the mode. */
2788 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2789 indicate to wait_for_inferior that a target should timeout if
2790 nothing is returned (instead of just blocking). Because of this,
2791 targets expecting an immediate response need to, internally, set
2792 things up so that the target_wait() is forced to eventually
2794 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2795 differentiate to its caller what the state of the target is after
2796 the initial open has been performed. Here we're assuming that
2797 the target has stopped. It should be possible to eventually have
2798 target_open() return to the caller an indication that the target
2799 is currently running and GDB state should be set to the same as
2800 for an async run. */
2801 wait_for_inferior ();
2803 /* Now that the inferior has stopped, do any bookkeeping like
2804 loading shared libraries. We want to do this before normal_stop,
2805 so that the displayed frame is up to date. */
2806 post_create_inferior (¤t_target
, from_tty
);
2811 /* Initialize static vars when a new inferior begins. */
2814 init_wait_for_inferior (void)
2816 /* These are meaningless until the first time through wait_for_inferior. */
2818 breakpoint_init_inferior (inf_starting
);
2820 clear_proceed_status (0);
2822 target_last_wait_ptid
= minus_one_ptid
;
2824 previous_inferior_ptid
= inferior_ptid
;
2826 /* Discard any skipped inlined frames. */
2827 clear_inline_frame_state (minus_one_ptid
);
2831 /* Data to be passed around while handling an event. This data is
2832 discarded between events. */
2833 struct execution_control_state
2836 /* The thread that got the event, if this was a thread event; NULL
2838 struct thread_info
*event_thread
;
2840 struct target_waitstatus ws
;
2841 int stop_func_filled_in
;
2842 CORE_ADDR stop_func_start
;
2843 CORE_ADDR stop_func_end
;
2844 const char *stop_func_name
;
2847 /* True if the event thread hit the single-step breakpoint of
2848 another thread. Thus the event doesn't cause a stop, the thread
2849 needs to be single-stepped past the single-step breakpoint before
2850 we can switch back to the original stepping thread. */
2851 int hit_singlestep_breakpoint
;
2854 static void handle_inferior_event (struct execution_control_state
*ecs
);
2856 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2857 struct execution_control_state
*ecs
);
2858 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2859 struct execution_control_state
*ecs
);
2860 static void handle_signal_stop (struct execution_control_state
*ecs
);
2861 static void check_exception_resume (struct execution_control_state
*,
2862 struct frame_info
*);
2864 static void end_stepping_range (struct execution_control_state
*ecs
);
2865 static void stop_waiting (struct execution_control_state
*ecs
);
2866 static void prepare_to_wait (struct execution_control_state
*ecs
);
2867 static void keep_going (struct execution_control_state
*ecs
);
2868 static void process_event_stop_test (struct execution_control_state
*ecs
);
2869 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
2871 /* Callback for iterate over threads. If the thread is stopped, but
2872 the user/frontend doesn't know about that yet, go through
2873 normal_stop, as if the thread had just stopped now. ARG points at
2874 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2875 ptid_is_pid(PTID) is true, applies to all threads of the process
2876 pointed at by PTID. Otherwise, apply only to the thread pointed by
2880 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2882 ptid_t ptid
= * (ptid_t
*) arg
;
2884 if ((ptid_equal (info
->ptid
, ptid
)
2885 || ptid_equal (minus_one_ptid
, ptid
)
2886 || (ptid_is_pid (ptid
)
2887 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2888 && is_running (info
->ptid
)
2889 && !is_executing (info
->ptid
))
2891 struct cleanup
*old_chain
;
2892 struct execution_control_state ecss
;
2893 struct execution_control_state
*ecs
= &ecss
;
2895 memset (ecs
, 0, sizeof (*ecs
));
2897 old_chain
= make_cleanup_restore_current_thread ();
2899 overlay_cache_invalid
= 1;
2900 /* Flush target cache before starting to handle each event.
2901 Target was running and cache could be stale. This is just a
2902 heuristic. Running threads may modify target memory, but we
2903 don't get any event. */
2904 target_dcache_invalidate ();
2906 /* Go through handle_inferior_event/normal_stop, so we always
2907 have consistent output as if the stop event had been
2909 ecs
->ptid
= info
->ptid
;
2910 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2911 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2912 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2914 handle_inferior_event (ecs
);
2916 if (!ecs
->wait_some_more
)
2918 struct thread_info
*tp
;
2922 /* Finish off the continuations. */
2923 tp
= inferior_thread ();
2924 do_all_intermediate_continuations_thread (tp
, 1);
2925 do_all_continuations_thread (tp
, 1);
2928 do_cleanups (old_chain
);
2934 /* This function is attached as a "thread_stop_requested" observer.
2935 Cleanup local state that assumed the PTID was to be resumed, and
2936 report the stop to the frontend. */
2939 infrun_thread_stop_requested (ptid_t ptid
)
2941 struct displaced_step_inferior_state
*displaced
;
2943 /* PTID was requested to stop. Remove it from the displaced
2944 stepping queue, so we don't try to resume it automatically. */
2946 for (displaced
= displaced_step_inferior_states
;
2948 displaced
= displaced
->next
)
2950 struct displaced_step_request
*it
, **prev_next_p
;
2952 it
= displaced
->step_request_queue
;
2953 prev_next_p
= &displaced
->step_request_queue
;
2956 if (ptid_match (it
->ptid
, ptid
))
2958 *prev_next_p
= it
->next
;
2964 prev_next_p
= &it
->next
;
2971 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2975 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2977 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2978 nullify_last_target_wait_ptid ();
2981 /* Delete the step resume, single-step and longjmp/exception resume
2982 breakpoints of TP. */
2985 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
2987 delete_step_resume_breakpoint (tp
);
2988 delete_exception_resume_breakpoint (tp
);
2989 delete_single_step_breakpoints (tp
);
2992 /* If the target still has execution, call FUNC for each thread that
2993 just stopped. In all-stop, that's all the non-exited threads; in
2994 non-stop, that's the current thread, only. */
2996 typedef void (*for_each_just_stopped_thread_callback_func
)
2997 (struct thread_info
*tp
);
3000 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3002 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3007 /* If in non-stop mode, only the current thread stopped. */
3008 func (inferior_thread ());
3012 struct thread_info
*tp
;
3014 /* In all-stop mode, all threads have stopped. */
3015 ALL_NON_EXITED_THREADS (tp
)
3022 /* Delete the step resume and longjmp/exception resume breakpoints of
3023 the threads that just stopped. */
3026 delete_just_stopped_threads_infrun_breakpoints (void)
3028 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3031 /* Delete the single-step breakpoints of the threads that just
3035 delete_just_stopped_threads_single_step_breakpoints (void)
3037 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3040 /* A cleanup wrapper. */
3043 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3045 delete_just_stopped_threads_infrun_breakpoints ();
3048 /* Pretty print the results of target_wait, for debugging purposes. */
3051 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3052 const struct target_waitstatus
*ws
)
3054 char *status_string
= target_waitstatus_to_string (ws
);
3055 struct ui_file
*tmp_stream
= mem_fileopen ();
3058 /* The text is split over several lines because it was getting too long.
3059 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3060 output as a unit; we want only one timestamp printed if debug_timestamp
3063 fprintf_unfiltered (tmp_stream
,
3064 "infrun: target_wait (%d.%ld.%ld",
3065 ptid_get_pid (waiton_ptid
),
3066 ptid_get_lwp (waiton_ptid
),
3067 ptid_get_tid (waiton_ptid
));
3068 if (ptid_get_pid (waiton_ptid
) != -1)
3069 fprintf_unfiltered (tmp_stream
,
3070 " [%s]", target_pid_to_str (waiton_ptid
));
3071 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3072 fprintf_unfiltered (tmp_stream
,
3073 "infrun: %d.%ld.%ld [%s],\n",
3074 ptid_get_pid (result_ptid
),
3075 ptid_get_lwp (result_ptid
),
3076 ptid_get_tid (result_ptid
),
3077 target_pid_to_str (result_ptid
));
3078 fprintf_unfiltered (tmp_stream
,
3082 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3084 /* This uses %s in part to handle %'s in the text, but also to avoid
3085 a gcc error: the format attribute requires a string literal. */
3086 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3088 xfree (status_string
);
3090 ui_file_delete (tmp_stream
);
3093 /* Prepare and stabilize the inferior for detaching it. E.g.,
3094 detaching while a thread is displaced stepping is a recipe for
3095 crashing it, as nothing would readjust the PC out of the scratch
3099 prepare_for_detach (void)
3101 struct inferior
*inf
= current_inferior ();
3102 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3103 struct cleanup
*old_chain_1
;
3104 struct displaced_step_inferior_state
*displaced
;
3106 displaced
= get_displaced_stepping_state (inf
->pid
);
3108 /* Is any thread of this process displaced stepping? If not,
3109 there's nothing else to do. */
3110 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3114 fprintf_unfiltered (gdb_stdlog
,
3115 "displaced-stepping in-process while detaching");
3117 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3120 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3122 struct cleanup
*old_chain_2
;
3123 struct execution_control_state ecss
;
3124 struct execution_control_state
*ecs
;
3127 memset (ecs
, 0, sizeof (*ecs
));
3129 overlay_cache_invalid
= 1;
3130 /* Flush target cache before starting to handle each event.
3131 Target was running and cache could be stale. This is just a
3132 heuristic. Running threads may modify target memory, but we
3133 don't get any event. */
3134 target_dcache_invalidate ();
3136 if (deprecated_target_wait_hook
)
3137 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
3139 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
3142 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3144 /* If an error happens while handling the event, propagate GDB's
3145 knowledge of the executing state to the frontend/user running
3147 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3150 /* Now figure out what to do with the result of the result. */
3151 handle_inferior_event (ecs
);
3153 /* No error, don't finish the state yet. */
3154 discard_cleanups (old_chain_2
);
3156 /* Breakpoints and watchpoints are not installed on the target
3157 at this point, and signals are passed directly to the
3158 inferior, so this must mean the process is gone. */
3159 if (!ecs
->wait_some_more
)
3161 discard_cleanups (old_chain_1
);
3162 error (_("Program exited while detaching"));
3166 discard_cleanups (old_chain_1
);
3169 /* Wait for control to return from inferior to debugger.
3171 If inferior gets a signal, we may decide to start it up again
3172 instead of returning. That is why there is a loop in this function.
3173 When this function actually returns it means the inferior
3174 should be left stopped and GDB should read more commands. */
3177 wait_for_inferior (void)
3179 struct cleanup
*old_cleanups
;
3180 struct cleanup
*thread_state_chain
;
3184 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3187 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3190 /* If an error happens while handling the event, propagate GDB's
3191 knowledge of the executing state to the frontend/user running
3193 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3197 struct execution_control_state ecss
;
3198 struct execution_control_state
*ecs
= &ecss
;
3199 ptid_t waiton_ptid
= minus_one_ptid
;
3201 memset (ecs
, 0, sizeof (*ecs
));
3203 overlay_cache_invalid
= 1;
3205 /* Flush target cache before starting to handle each event.
3206 Target was running and cache could be stale. This is just a
3207 heuristic. Running threads may modify target memory, but we
3208 don't get any event. */
3209 target_dcache_invalidate ();
3211 if (deprecated_target_wait_hook
)
3212 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
3214 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
3217 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3219 /* Now figure out what to do with the result of the result. */
3220 handle_inferior_event (ecs
);
3222 if (!ecs
->wait_some_more
)
3226 /* No error, don't finish the state yet. */
3227 discard_cleanups (thread_state_chain
);
3229 do_cleanups (old_cleanups
);
3232 /* Cleanup that reinstalls the readline callback handler, if the
3233 target is running in the background. If while handling the target
3234 event something triggered a secondary prompt, like e.g., a
3235 pagination prompt, we'll have removed the callback handler (see
3236 gdb_readline_wrapper_line). Need to do this as we go back to the
3237 event loop, ready to process further input. Note this has no
3238 effect if the handler hasn't actually been removed, because calling
3239 rl_callback_handler_install resets the line buffer, thus losing
3243 reinstall_readline_callback_handler_cleanup (void *arg
)
3245 if (!interpreter_async
)
3247 /* We're not going back to the top level event loop yet. Don't
3248 install the readline callback, as it'd prep the terminal,
3249 readline-style (raw, noecho) (e.g., --batch). We'll install
3250 it the next time the prompt is displayed, when we're ready
3255 if (async_command_editing_p
&& !sync_execution
)
3256 gdb_rl_callback_handler_reinstall ();
3259 /* Asynchronous version of wait_for_inferior. It is called by the
3260 event loop whenever a change of state is detected on the file
3261 descriptor corresponding to the target. It can be called more than
3262 once to complete a single execution command. In such cases we need
3263 to keep the state in a global variable ECSS. If it is the last time
3264 that this function is called for a single execution command, then
3265 report to the user that the inferior has stopped, and do the
3266 necessary cleanups. */
3269 fetch_inferior_event (void *client_data
)
3271 struct execution_control_state ecss
;
3272 struct execution_control_state
*ecs
= &ecss
;
3273 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3274 struct cleanup
*ts_old_chain
;
3275 int was_sync
= sync_execution
;
3277 ptid_t waiton_ptid
= minus_one_ptid
;
3279 memset (ecs
, 0, sizeof (*ecs
));
3281 /* End up with readline processing input, if necessary. */
3282 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3284 /* We're handling a live event, so make sure we're doing live
3285 debugging. If we're looking at traceframes while the target is
3286 running, we're going to need to get back to that mode after
3287 handling the event. */
3290 make_cleanup_restore_current_traceframe ();
3291 set_current_traceframe (-1);
3295 /* In non-stop mode, the user/frontend should not notice a thread
3296 switch due to internal events. Make sure we reverse to the
3297 user selected thread and frame after handling the event and
3298 running any breakpoint commands. */
3299 make_cleanup_restore_current_thread ();
3301 overlay_cache_invalid
= 1;
3302 /* Flush target cache before starting to handle each event. Target
3303 was running and cache could be stale. This is just a heuristic.
3304 Running threads may modify target memory, but we don't get any
3306 target_dcache_invalidate ();
3308 make_cleanup_restore_integer (&execution_direction
);
3309 execution_direction
= target_execution_direction ();
3311 if (deprecated_target_wait_hook
)
3313 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3315 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3318 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3320 /* If an error happens while handling the event, propagate GDB's
3321 knowledge of the executing state to the frontend/user running
3324 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3326 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3328 /* Get executed before make_cleanup_restore_current_thread above to apply
3329 still for the thread which has thrown the exception. */
3330 make_bpstat_clear_actions_cleanup ();
3332 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3334 /* Now figure out what to do with the result of the result. */
3335 handle_inferior_event (ecs
);
3337 if (!ecs
->wait_some_more
)
3339 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3341 delete_just_stopped_threads_infrun_breakpoints ();
3343 /* We may not find an inferior if this was a process exit. */
3344 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3347 if (target_has_execution
3348 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
3349 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3350 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3351 && ecs
->event_thread
->step_multi
3352 && ecs
->event_thread
->control
.stop_step
)
3353 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
3356 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3361 /* No error, don't finish the thread states yet. */
3362 discard_cleanups (ts_old_chain
);
3364 /* Revert thread and frame. */
3365 do_cleanups (old_chain
);
3367 /* If the inferior was in sync execution mode, and now isn't,
3368 restore the prompt (a synchronous execution command has finished,
3369 and we're ready for input). */
3370 if (interpreter_async
&& was_sync
&& !sync_execution
)
3371 observer_notify_sync_execution_done ();
3375 && exec_done_display_p
3376 && (ptid_equal (inferior_ptid
, null_ptid
)
3377 || !is_running (inferior_ptid
)))
3378 printf_unfiltered (_("completed.\n"));
3381 /* Record the frame and location we're currently stepping through. */
3383 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3385 struct thread_info
*tp
= inferior_thread ();
3387 tp
->control
.step_frame_id
= get_frame_id (frame
);
3388 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3390 tp
->current_symtab
= sal
.symtab
;
3391 tp
->current_line
= sal
.line
;
3394 /* Clear context switchable stepping state. */
3397 init_thread_stepping_state (struct thread_info
*tss
)
3399 tss
->stepped_breakpoint
= 0;
3400 tss
->stepping_over_breakpoint
= 0;
3401 tss
->stepping_over_watchpoint
= 0;
3402 tss
->step_after_step_resume_breakpoint
= 0;
3405 /* Set the cached copy of the last ptid/waitstatus. */
3408 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
3410 target_last_wait_ptid
= ptid
;
3411 target_last_waitstatus
= status
;
3414 /* Return the cached copy of the last pid/waitstatus returned by
3415 target_wait()/deprecated_target_wait_hook(). The data is actually
3416 cached by handle_inferior_event(), which gets called immediately
3417 after target_wait()/deprecated_target_wait_hook(). */
3420 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
3422 *ptidp
= target_last_wait_ptid
;
3423 *status
= target_last_waitstatus
;
3427 nullify_last_target_wait_ptid (void)
3429 target_last_wait_ptid
= minus_one_ptid
;
3432 /* Switch thread contexts. */
3435 context_switch (ptid_t ptid
)
3437 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
3439 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
3440 target_pid_to_str (inferior_ptid
));
3441 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
3442 target_pid_to_str (ptid
));
3445 switch_to_thread (ptid
);
3449 adjust_pc_after_break (struct execution_control_state
*ecs
)
3451 struct regcache
*regcache
;
3452 struct gdbarch
*gdbarch
;
3453 struct address_space
*aspace
;
3454 CORE_ADDR breakpoint_pc
, decr_pc
;
3456 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
3457 we aren't, just return.
3459 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
3460 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
3461 implemented by software breakpoints should be handled through the normal
3464 NOTE drow/2004-01-31: On some targets, breakpoints may generate
3465 different signals (SIGILL or SIGEMT for instance), but it is less
3466 clear where the PC is pointing afterwards. It may not match
3467 gdbarch_decr_pc_after_break. I don't know any specific target that
3468 generates these signals at breakpoints (the code has been in GDB since at
3469 least 1992) so I can not guess how to handle them here.
3471 In earlier versions of GDB, a target with
3472 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
3473 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
3474 target with both of these set in GDB history, and it seems unlikely to be
3475 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
3477 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
3480 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
3483 /* In reverse execution, when a breakpoint is hit, the instruction
3484 under it has already been de-executed. The reported PC always
3485 points at the breakpoint address, so adjusting it further would
3486 be wrong. E.g., consider this case on a decr_pc_after_break == 1
3489 B1 0x08000000 : INSN1
3490 B2 0x08000001 : INSN2
3492 PC -> 0x08000003 : INSN4
3494 Say you're stopped at 0x08000003 as above. Reverse continuing
3495 from that point should hit B2 as below. Reading the PC when the
3496 SIGTRAP is reported should read 0x08000001 and INSN2 should have
3497 been de-executed already.
3499 B1 0x08000000 : INSN1
3500 B2 PC -> 0x08000001 : INSN2
3504 We can't apply the same logic as for forward execution, because
3505 we would wrongly adjust the PC to 0x08000000, since there's a
3506 breakpoint at PC - 1. We'd then report a hit on B1, although
3507 INSN1 hadn't been de-executed yet. Doing nothing is the correct
3509 if (execution_direction
== EXEC_REVERSE
)
3512 /* If the target can tell whether the thread hit a SW breakpoint,
3513 trust it. Targets that can tell also adjust the PC
3515 if (target_supports_stopped_by_sw_breakpoint ())
3518 /* Note that relying on whether a breakpoint is planted in memory to
3519 determine this can fail. E.g,. the breakpoint could have been
3520 removed since. Or the thread could have been told to step an
3521 instruction the size of a breakpoint instruction, and only
3522 _after_ was a breakpoint inserted at its address. */
3524 /* If this target does not decrement the PC after breakpoints, then
3525 we have nothing to do. */
3526 regcache
= get_thread_regcache (ecs
->ptid
);
3527 gdbarch
= get_regcache_arch (regcache
);
3529 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3533 aspace
= get_regcache_aspace (regcache
);
3535 /* Find the location where (if we've hit a breakpoint) the
3536 breakpoint would be. */
3537 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
3539 /* If the target can't tell whether a software breakpoint triggered,
3540 fallback to figuring it out based on breakpoints we think were
3541 inserted in the target, and on whether the thread was stepped or
3544 /* Check whether there actually is a software breakpoint inserted at
3547 If in non-stop mode, a race condition is possible where we've
3548 removed a breakpoint, but stop events for that breakpoint were
3549 already queued and arrive later. To suppress those spurious
3550 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3551 and retire them after a number of stop events are reported. Note
3552 this is an heuristic and can thus get confused. The real fix is
3553 to get the "stopped by SW BP and needs adjustment" info out of
3554 the target/kernel (and thus never reach here; see above). */
3555 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3556 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3558 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
3560 if (record_full_is_used ())
3561 record_full_gdb_operation_disable_set ();
3563 /* When using hardware single-step, a SIGTRAP is reported for both
3564 a completed single-step and a software breakpoint. Need to
3565 differentiate between the two, as the latter needs adjusting
3566 but the former does not.
3568 The SIGTRAP can be due to a completed hardware single-step only if
3569 - we didn't insert software single-step breakpoints
3570 - this thread is currently being stepped
3572 If any of these events did not occur, we must have stopped due
3573 to hitting a software breakpoint, and have to back up to the
3576 As a special case, we could have hardware single-stepped a
3577 software breakpoint. In this case (prev_pc == breakpoint_pc),
3578 we also need to back up to the breakpoint address. */
3580 if (thread_has_single_step_breakpoints_set (ecs
->event_thread
)
3581 || !currently_stepping (ecs
->event_thread
)
3582 || (ecs
->event_thread
->stepped_breakpoint
3583 && ecs
->event_thread
->prev_pc
== breakpoint_pc
))
3584 regcache_write_pc (regcache
, breakpoint_pc
);
3586 do_cleanups (old_cleanups
);
3591 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3593 for (frame
= get_prev_frame (frame
);
3595 frame
= get_prev_frame (frame
))
3597 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3599 if (get_frame_type (frame
) != INLINE_FRAME
)
3606 /* Auxiliary function that handles syscall entry/return events.
3607 It returns 1 if the inferior should keep going (and GDB
3608 should ignore the event), or 0 if the event deserves to be
3612 handle_syscall_event (struct execution_control_state
*ecs
)
3614 struct regcache
*regcache
;
3617 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3618 context_switch (ecs
->ptid
);
3620 regcache
= get_thread_regcache (ecs
->ptid
);
3621 syscall_number
= ecs
->ws
.value
.syscall_number
;
3622 stop_pc
= regcache_read_pc (regcache
);
3624 if (catch_syscall_enabled () > 0
3625 && catching_syscall_number (syscall_number
) > 0)
3628 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3631 ecs
->event_thread
->control
.stop_bpstat
3632 = bpstat_stop_status (get_regcache_aspace (regcache
),
3633 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3635 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3637 /* Catchpoint hit. */
3642 /* If no catchpoint triggered for this, then keep going. */
3647 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3650 fill_in_stop_func (struct gdbarch
*gdbarch
,
3651 struct execution_control_state
*ecs
)
3653 if (!ecs
->stop_func_filled_in
)
3655 /* Don't care about return value; stop_func_start and stop_func_name
3656 will both be 0 if it doesn't work. */
3657 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3658 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3659 ecs
->stop_func_start
3660 += gdbarch_deprecated_function_start_offset (gdbarch
);
3662 if (gdbarch_skip_entrypoint_p (gdbarch
))
3663 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
3664 ecs
->stop_func_start
);
3666 ecs
->stop_func_filled_in
= 1;
3671 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
3673 static enum stop_kind
3674 get_inferior_stop_soon (ptid_t ptid
)
3676 struct inferior
*inf
= find_inferior_ptid (ptid
);
3678 gdb_assert (inf
!= NULL
);
3679 return inf
->control
.stop_soon
;
3682 /* Given an execution control state that has been freshly filled in by
3683 an event from the inferior, figure out what it means and take
3686 The alternatives are:
3688 1) stop_waiting and return; to really stop and return to the
3691 2) keep_going and return; to wait for the next event (set
3692 ecs->event_thread->stepping_over_breakpoint to 1 to single step
3696 handle_inferior_event (struct execution_control_state
*ecs
)
3698 enum stop_kind stop_soon
;
3700 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3702 /* We had an event in the inferior, but we are not interested in
3703 handling it at this level. The lower layers have already
3704 done what needs to be done, if anything.
3706 One of the possible circumstances for this is when the
3707 inferior produces output for the console. The inferior has
3708 not stopped, and we are ignoring the event. Another possible
3709 circumstance is any event which the lower level knows will be
3710 reported multiple times without an intervening resume. */
3712 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3713 prepare_to_wait (ecs
);
3717 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3718 && target_can_async_p () && !sync_execution
)
3720 /* There were no unwaited-for children left in the target, but,
3721 we're not synchronously waiting for events either. Just
3722 ignore. Otherwise, if we were running a synchronous
3723 execution command, we need to cancel it and give the user
3724 back the terminal. */
3726 fprintf_unfiltered (gdb_stdlog
,
3727 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3728 prepare_to_wait (ecs
);
3732 /* Cache the last pid/waitstatus. */
3733 set_last_target_status (ecs
->ptid
, ecs
->ws
);
3735 /* Always clear state belonging to the previous time we stopped. */
3736 stop_stack_dummy
= STOP_NONE
;
3738 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3740 /* No unwaited-for children left. IOW, all resumed children
3743 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3745 stop_print_frame
= 0;
3750 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3751 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
3753 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3754 /* If it's a new thread, add it to the thread database. */
3755 if (ecs
->event_thread
== NULL
)
3756 ecs
->event_thread
= add_thread (ecs
->ptid
);
3758 /* Disable range stepping. If the next step request could use a
3759 range, this will be end up re-enabled then. */
3760 ecs
->event_thread
->control
.may_range_step
= 0;
3763 /* Dependent on valid ECS->EVENT_THREAD. */
3764 adjust_pc_after_break (ecs
);
3766 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3767 reinit_frame_cache ();
3769 breakpoint_retire_moribund ();
3771 /* First, distinguish signals caused by the debugger from signals
3772 that have to do with the program's own actions. Note that
3773 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3774 on the operating system version. Here we detect when a SIGILL or
3775 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3776 something similar for SIGSEGV, since a SIGSEGV will be generated
3777 when we're trying to execute a breakpoint instruction on a
3778 non-executable stack. This happens for call dummy breakpoints
3779 for architectures like SPARC that place call dummies on the
3781 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3782 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3783 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3784 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3786 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3788 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3789 regcache_read_pc (regcache
)))
3792 fprintf_unfiltered (gdb_stdlog
,
3793 "infrun: Treating signal as SIGTRAP\n");
3794 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3798 /* Mark the non-executing threads accordingly. In all-stop, all
3799 threads of all processes are stopped when we get any event
3800 reported. In non-stop mode, only the event thread stops. If
3801 we're handling a process exit in non-stop mode, there's nothing
3802 to do, as threads of the dead process are gone, and threads of
3803 any other process were left running. */
3805 set_executing (minus_one_ptid
, 0);
3806 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3807 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3808 set_executing (ecs
->ptid
, 0);
3810 switch (ecs
->ws
.kind
)
3812 case TARGET_WAITKIND_LOADED
:
3814 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3815 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3816 context_switch (ecs
->ptid
);
3817 /* Ignore gracefully during startup of the inferior, as it might
3818 be the shell which has just loaded some objects, otherwise
3819 add the symbols for the newly loaded objects. Also ignore at
3820 the beginning of an attach or remote session; we will query
3821 the full list of libraries once the connection is
3824 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
3825 if (stop_soon
== NO_STOP_QUIETLY
)
3827 struct regcache
*regcache
;
3829 regcache
= get_thread_regcache (ecs
->ptid
);
3831 handle_solib_event ();
3833 ecs
->event_thread
->control
.stop_bpstat
3834 = bpstat_stop_status (get_regcache_aspace (regcache
),
3835 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3837 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3839 /* A catchpoint triggered. */
3840 process_event_stop_test (ecs
);
3844 /* If requested, stop when the dynamic linker notifies
3845 gdb of events. This allows the user to get control
3846 and place breakpoints in initializer routines for
3847 dynamically loaded objects (among other things). */
3848 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3849 if (stop_on_solib_events
)
3851 /* Make sure we print "Stopped due to solib-event" in
3853 stop_print_frame
= 1;
3860 /* If we are skipping through a shell, or through shared library
3861 loading that we aren't interested in, resume the program. If
3862 we're running the program normally, also resume. */
3863 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3865 /* Loading of shared libraries might have changed breakpoint
3866 addresses. Make sure new breakpoints are inserted. */
3867 if (stop_soon
== NO_STOP_QUIETLY
)
3868 insert_breakpoints ();
3869 resume (GDB_SIGNAL_0
);
3870 prepare_to_wait (ecs
);
3874 /* But stop if we're attaching or setting up a remote
3876 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3877 || stop_soon
== STOP_QUIETLY_REMOTE
)
3880 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3885 internal_error (__FILE__
, __LINE__
,
3886 _("unhandled stop_soon: %d"), (int) stop_soon
);
3888 case TARGET_WAITKIND_SPURIOUS
:
3890 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3891 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3892 context_switch (ecs
->ptid
);
3893 resume (GDB_SIGNAL_0
);
3894 prepare_to_wait (ecs
);
3897 case TARGET_WAITKIND_EXITED
:
3898 case TARGET_WAITKIND_SIGNALLED
:
3901 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3902 fprintf_unfiltered (gdb_stdlog
,
3903 "infrun: TARGET_WAITKIND_EXITED\n");
3905 fprintf_unfiltered (gdb_stdlog
,
3906 "infrun: TARGET_WAITKIND_SIGNALLED\n");
3909 inferior_ptid
= ecs
->ptid
;
3910 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
3911 set_current_program_space (current_inferior ()->pspace
);
3912 handle_vfork_child_exec_or_exit (0);
3913 target_terminal_ours (); /* Must do this before mourn anyway. */
3915 /* Clearing any previous state of convenience variables. */
3916 clear_exit_convenience_vars ();
3918 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3920 /* Record the exit code in the convenience variable $_exitcode, so
3921 that the user can inspect this again later. */
3922 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3923 (LONGEST
) ecs
->ws
.value
.integer
);
3925 /* Also record this in the inferior itself. */
3926 current_inferior ()->has_exit_code
= 1;
3927 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3929 /* Support the --return-child-result option. */
3930 return_child_result_value
= ecs
->ws
.value
.integer
;
3932 observer_notify_exited (ecs
->ws
.value
.integer
);
3936 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3937 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3939 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
3941 /* Set the value of the internal variable $_exitsignal,
3942 which holds the signal uncaught by the inferior. */
3943 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
3944 gdbarch_gdb_signal_to_target (gdbarch
,
3945 ecs
->ws
.value
.sig
));
3949 /* We don't have access to the target's method used for
3950 converting between signal numbers (GDB's internal
3951 representation <-> target's representation).
3952 Therefore, we cannot do a good job at displaying this
3953 information to the user. It's better to just warn
3954 her about it (if infrun debugging is enabled), and
3957 fprintf_filtered (gdb_stdlog
, _("\
3958 Cannot fill $_exitsignal with the correct signal number.\n"));
3961 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
3964 gdb_flush (gdb_stdout
);
3965 target_mourn_inferior ();
3966 stop_print_frame
= 0;
3970 /* The following are the only cases in which we keep going;
3971 the above cases end in a continue or goto. */
3972 case TARGET_WAITKIND_FORKED
:
3973 case TARGET_WAITKIND_VFORKED
:
3976 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3977 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3979 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
3982 /* Check whether the inferior is displaced stepping. */
3984 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3985 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3986 struct displaced_step_inferior_state
*displaced
3987 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3989 /* If checking displaced stepping is supported, and thread
3990 ecs->ptid is displaced stepping. */
3991 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3993 struct inferior
*parent_inf
3994 = find_inferior_ptid (ecs
->ptid
);
3995 struct regcache
*child_regcache
;
3996 CORE_ADDR parent_pc
;
3998 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3999 indicating that the displaced stepping of syscall instruction
4000 has been done. Perform cleanup for parent process here. Note
4001 that this operation also cleans up the child process for vfork,
4002 because their pages are shared. */
4003 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
4005 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4007 /* Restore scratch pad for child process. */
4008 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
4011 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
4012 the child's PC is also within the scratchpad. Set the child's PC
4013 to the parent's PC value, which has already been fixed up.
4014 FIXME: we use the parent's aspace here, although we're touching
4015 the child, because the child hasn't been added to the inferior
4016 list yet at this point. */
4019 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
4021 parent_inf
->aspace
);
4022 /* Read PC value of parent process. */
4023 parent_pc
= regcache_read_pc (regcache
);
4025 if (debug_displaced
)
4026 fprintf_unfiltered (gdb_stdlog
,
4027 "displaced: write child pc from %s to %s\n",
4029 regcache_read_pc (child_regcache
)),
4030 paddress (gdbarch
, parent_pc
));
4032 regcache_write_pc (child_regcache
, parent_pc
);
4036 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4037 context_switch (ecs
->ptid
);
4039 /* Immediately detach breakpoints from the child before there's
4040 any chance of letting the user delete breakpoints from the
4041 breakpoint lists. If we don't do this early, it's easy to
4042 leave left over traps in the child, vis: "break foo; catch
4043 fork; c; <fork>; del; c; <child calls foo>". We only follow
4044 the fork on the last `continue', and by that time the
4045 breakpoint at "foo" is long gone from the breakpoint table.
4046 If we vforked, then we don't need to unpatch here, since both
4047 parent and child are sharing the same memory pages; we'll
4048 need to unpatch at follow/detach time instead to be certain
4049 that new breakpoints added between catchpoint hit time and
4050 vfork follow are detached. */
4051 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
4053 /* This won't actually modify the breakpoint list, but will
4054 physically remove the breakpoints from the child. */
4055 detach_breakpoints (ecs
->ws
.value
.related_pid
);
4058 delete_just_stopped_threads_single_step_breakpoints ();
4060 /* In case the event is caught by a catchpoint, remember that
4061 the event is to be followed at the next resume of the thread,
4062 and not immediately. */
4063 ecs
->event_thread
->pending_follow
= ecs
->ws
;
4065 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4067 ecs
->event_thread
->control
.stop_bpstat
4068 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4069 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4071 /* If no catchpoint triggered for this, then keep going. Note
4072 that we're interested in knowing the bpstat actually causes a
4073 stop, not just if it may explain the signal. Software
4074 watchpoints, for example, always appear in the bpstat. */
4075 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4081 = (follow_fork_mode_string
== follow_fork_mode_child
);
4083 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4085 should_resume
= follow_fork ();
4088 child
= ecs
->ws
.value
.related_pid
;
4090 /* In non-stop mode, also resume the other branch. */
4091 if (non_stop
&& !detach_fork
)
4094 switch_to_thread (parent
);
4096 switch_to_thread (child
);
4098 ecs
->event_thread
= inferior_thread ();
4099 ecs
->ptid
= inferior_ptid
;
4104 switch_to_thread (child
);
4106 switch_to_thread (parent
);
4108 ecs
->event_thread
= inferior_thread ();
4109 ecs
->ptid
= inferior_ptid
;
4117 process_event_stop_test (ecs
);
4120 case TARGET_WAITKIND_VFORK_DONE
:
4121 /* Done with the shared memory region. Re-insert breakpoints in
4122 the parent, and keep going. */
4125 fprintf_unfiltered (gdb_stdlog
,
4126 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
4128 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4129 context_switch (ecs
->ptid
);
4131 current_inferior ()->waiting_for_vfork_done
= 0;
4132 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
4133 /* This also takes care of reinserting breakpoints in the
4134 previously locked inferior. */
4138 case TARGET_WAITKIND_EXECD
:
4140 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
4142 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4143 context_switch (ecs
->ptid
);
4145 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4147 /* Do whatever is necessary to the parent branch of the vfork. */
4148 handle_vfork_child_exec_or_exit (1);
4150 /* This causes the eventpoints and symbol table to be reset.
4151 Must do this now, before trying to determine whether to
4153 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
4155 ecs
->event_thread
->control
.stop_bpstat
4156 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4157 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4159 /* Note that this may be referenced from inside
4160 bpstat_stop_status above, through inferior_has_execd. */
4161 xfree (ecs
->ws
.value
.execd_pathname
);
4162 ecs
->ws
.value
.execd_pathname
= NULL
;
4164 /* If no catchpoint triggered for this, then keep going. */
4165 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4167 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4171 process_event_stop_test (ecs
);
4174 /* Be careful not to try to gather much state about a thread
4175 that's in a syscall. It's frequently a losing proposition. */
4176 case TARGET_WAITKIND_SYSCALL_ENTRY
:
4178 fprintf_unfiltered (gdb_stdlog
,
4179 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
4180 /* Getting the current syscall number. */
4181 if (handle_syscall_event (ecs
) == 0)
4182 process_event_stop_test (ecs
);
4185 /* Before examining the threads further, step this thread to
4186 get it entirely out of the syscall. (We get notice of the
4187 event when the thread is just on the verge of exiting a
4188 syscall. Stepping one instruction seems to get it back
4190 case TARGET_WAITKIND_SYSCALL_RETURN
:
4192 fprintf_unfiltered (gdb_stdlog
,
4193 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
4194 if (handle_syscall_event (ecs
) == 0)
4195 process_event_stop_test (ecs
);
4198 case TARGET_WAITKIND_STOPPED
:
4200 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
4201 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
4202 handle_signal_stop (ecs
);
4205 case TARGET_WAITKIND_NO_HISTORY
:
4207 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
4208 /* Reverse execution: target ran out of history info. */
4210 delete_just_stopped_threads_single_step_breakpoints ();
4211 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4212 observer_notify_no_history ();
4218 /* Come here when the program has stopped with a signal. */
4221 handle_signal_stop (struct execution_control_state
*ecs
)
4223 struct frame_info
*frame
;
4224 struct gdbarch
*gdbarch
;
4225 int stopped_by_watchpoint
;
4226 enum stop_kind stop_soon
;
4229 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
4231 /* Do we need to clean up the state of a thread that has
4232 completed a displaced single-step? (Doing so usually affects
4233 the PC, so do it here, before we set stop_pc.) */
4234 displaced_step_fixup (ecs
->ptid
,
4235 ecs
->event_thread
->suspend
.stop_signal
);
4237 /* If we either finished a single-step or hit a breakpoint, but
4238 the user wanted this thread to be stopped, pretend we got a
4239 SIG0 (generic unsignaled stop). */
4240 if (ecs
->event_thread
->stop_requested
4241 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4242 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4244 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4248 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4249 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4250 struct cleanup
*old_chain
= save_inferior_ptid ();
4252 inferior_ptid
= ecs
->ptid
;
4254 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
4255 paddress (gdbarch
, stop_pc
));
4256 if (target_stopped_by_watchpoint ())
4260 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
4262 if (target_stopped_data_address (¤t_target
, &addr
))
4263 fprintf_unfiltered (gdb_stdlog
,
4264 "infrun: stopped data address = %s\n",
4265 paddress (gdbarch
, addr
));
4267 fprintf_unfiltered (gdb_stdlog
,
4268 "infrun: (no data address available)\n");
4271 do_cleanups (old_chain
);
4274 /* This is originated from start_remote(), start_inferior() and
4275 shared libraries hook functions. */
4276 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4277 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4279 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4280 context_switch (ecs
->ptid
);
4282 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4283 stop_print_frame
= 1;
4288 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4291 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4292 context_switch (ecs
->ptid
);
4294 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4295 stop_print_frame
= 0;
4300 /* This originates from attach_command(). We need to overwrite
4301 the stop_signal here, because some kernels don't ignore a
4302 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4303 See more comments in inferior.h. On the other hand, if we
4304 get a non-SIGSTOP, report it to the user - assume the backend
4305 will handle the SIGSTOP if it should show up later.
4307 Also consider that the attach is complete when we see a
4308 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4309 target extended-remote report it instead of a SIGSTOP
4310 (e.g. gdbserver). We already rely on SIGTRAP being our
4311 signal, so this is no exception.
4313 Also consider that the attach is complete when we see a
4314 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4315 the target to stop all threads of the inferior, in case the
4316 low level attach operation doesn't stop them implicitly. If
4317 they weren't stopped implicitly, then the stub will report a
4318 GDB_SIGNAL_0, meaning: stopped for no particular reason
4319 other than GDB's request. */
4320 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4321 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4322 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4323 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4325 stop_print_frame
= 1;
4327 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4331 /* See if something interesting happened to the non-current thread. If
4332 so, then switch to that thread. */
4333 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4336 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
4338 context_switch (ecs
->ptid
);
4340 if (deprecated_context_hook
)
4341 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
4344 /* At this point, get hold of the now-current thread's frame. */
4345 frame
= get_current_frame ();
4346 gdbarch
= get_frame_arch (frame
);
4348 /* Pull the single step breakpoints out of the target. */
4349 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4351 struct regcache
*regcache
;
4352 struct address_space
*aspace
;
4355 regcache
= get_thread_regcache (ecs
->ptid
);
4356 aspace
= get_regcache_aspace (regcache
);
4357 pc
= regcache_read_pc (regcache
);
4359 /* However, before doing so, if this single-step breakpoint was
4360 actually for another thread, set this thread up for moving
4362 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
4365 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
4369 fprintf_unfiltered (gdb_stdlog
,
4370 "infrun: [%s] hit another thread's "
4371 "single-step breakpoint\n",
4372 target_pid_to_str (ecs
->ptid
));
4374 ecs
->hit_singlestep_breakpoint
= 1;
4381 fprintf_unfiltered (gdb_stdlog
,
4382 "infrun: [%s] hit its "
4383 "single-step breakpoint\n",
4384 target_pid_to_str (ecs
->ptid
));
4388 delete_just_stopped_threads_single_step_breakpoints ();
4390 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4391 && ecs
->event_thread
->control
.trap_expected
4392 && ecs
->event_thread
->stepping_over_watchpoint
)
4393 stopped_by_watchpoint
= 0;
4395 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
4397 /* If necessary, step over this watchpoint. We'll be back to display
4399 if (stopped_by_watchpoint
4400 && (target_have_steppable_watchpoint
4401 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4403 /* At this point, we are stopped at an instruction which has
4404 attempted to write to a piece of memory under control of
4405 a watchpoint. The instruction hasn't actually executed
4406 yet. If we were to evaluate the watchpoint expression
4407 now, we would get the old value, and therefore no change
4408 would seem to have occurred.
4410 In order to make watchpoints work `right', we really need
4411 to complete the memory write, and then evaluate the
4412 watchpoint expression. We do this by single-stepping the
4415 It may not be necessary to disable the watchpoint to step over
4416 it. For example, the PA can (with some kernel cooperation)
4417 single step over a watchpoint without disabling the watchpoint.
4419 It is far more common to need to disable a watchpoint to step
4420 the inferior over it. If we have non-steppable watchpoints,
4421 we must disable the current watchpoint; it's simplest to
4422 disable all watchpoints.
4424 Any breakpoint at PC must also be stepped over -- if there's
4425 one, it will have already triggered before the watchpoint
4426 triggered, and we either already reported it to the user, or
4427 it didn't cause a stop and we called keep_going. In either
4428 case, if there was a breakpoint at PC, we must be trying to
4430 ecs
->event_thread
->stepping_over_watchpoint
= 1;
4435 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4436 ecs
->event_thread
->stepping_over_watchpoint
= 0;
4437 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4438 ecs
->event_thread
->control
.stop_step
= 0;
4439 stop_print_frame
= 1;
4440 stopped_by_random_signal
= 0;
4442 /* Hide inlined functions starting here, unless we just performed stepi or
4443 nexti. After stepi and nexti, always show the innermost frame (not any
4444 inline function call sites). */
4445 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4447 struct address_space
*aspace
=
4448 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4450 /* skip_inline_frames is expensive, so we avoid it if we can
4451 determine that the address is one where functions cannot have
4452 been inlined. This improves performance with inferiors that
4453 load a lot of shared libraries, because the solib event
4454 breakpoint is defined as the address of a function (i.e. not
4455 inline). Note that we have to check the previous PC as well
4456 as the current one to catch cases when we have just
4457 single-stepped off a breakpoint prior to reinstating it.
4458 Note that we're assuming that the code we single-step to is
4459 not inline, but that's not definitive: there's nothing
4460 preventing the event breakpoint function from containing
4461 inlined code, and the single-step ending up there. If the
4462 user had set a breakpoint on that inlined code, the missing
4463 skip_inline_frames call would break things. Fortunately
4464 that's an extremely unlikely scenario. */
4465 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4466 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4467 && ecs
->event_thread
->control
.trap_expected
4468 && pc_at_non_inline_function (aspace
,
4469 ecs
->event_thread
->prev_pc
,
4472 skip_inline_frames (ecs
->ptid
);
4474 /* Re-fetch current thread's frame in case that invalidated
4476 frame
= get_current_frame ();
4477 gdbarch
= get_frame_arch (frame
);
4481 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4482 && ecs
->event_thread
->control
.trap_expected
4483 && gdbarch_single_step_through_delay_p (gdbarch
)
4484 && currently_stepping (ecs
->event_thread
))
4486 /* We're trying to step off a breakpoint. Turns out that we're
4487 also on an instruction that needs to be stepped multiple
4488 times before it's been fully executing. E.g., architectures
4489 with a delay slot. It needs to be stepped twice, once for
4490 the instruction and once for the delay slot. */
4491 int step_through_delay
4492 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4494 if (debug_infrun
&& step_through_delay
)
4495 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4496 if (ecs
->event_thread
->control
.step_range_end
== 0
4497 && step_through_delay
)
4499 /* The user issued a continue when stopped at a breakpoint.
4500 Set up for another trap and get out of here. */
4501 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4505 else if (step_through_delay
)
4507 /* The user issued a step when stopped at a breakpoint.
4508 Maybe we should stop, maybe we should not - the delay
4509 slot *might* correspond to a line of source. In any
4510 case, don't decide that here, just set
4511 ecs->stepping_over_breakpoint, making sure we
4512 single-step again before breakpoints are re-inserted. */
4513 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4517 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4518 handles this event. */
4519 ecs
->event_thread
->control
.stop_bpstat
4520 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4521 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4523 /* Following in case break condition called a
4525 stop_print_frame
= 1;
4527 /* This is where we handle "moribund" watchpoints. Unlike
4528 software breakpoints traps, hardware watchpoint traps are
4529 always distinguishable from random traps. If no high-level
4530 watchpoint is associated with the reported stop data address
4531 anymore, then the bpstat does not explain the signal ---
4532 simply make sure to ignore it if `stopped_by_watchpoint' is
4536 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4537 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4539 && stopped_by_watchpoint
)
4540 fprintf_unfiltered (gdb_stdlog
,
4541 "infrun: no user watchpoint explains "
4542 "watchpoint SIGTRAP, ignoring\n");
4544 /* NOTE: cagney/2003-03-29: These checks for a random signal
4545 at one stage in the past included checks for an inferior
4546 function call's call dummy's return breakpoint. The original
4547 comment, that went with the test, read:
4549 ``End of a stack dummy. Some systems (e.g. Sony news) give
4550 another signal besides SIGTRAP, so check here as well as
4553 If someone ever tries to get call dummys on a
4554 non-executable stack to work (where the target would stop
4555 with something like a SIGSEGV), then those tests might need
4556 to be re-instated. Given, however, that the tests were only
4557 enabled when momentary breakpoints were not being used, I
4558 suspect that it won't be the case.
4560 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4561 be necessary for call dummies on a non-executable stack on
4564 /* See if the breakpoints module can explain the signal. */
4566 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4567 ecs
->event_thread
->suspend
.stop_signal
);
4569 /* Maybe this was a trap for a software breakpoint that has since
4571 if (random_signal
&& target_stopped_by_sw_breakpoint ())
4573 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
4575 struct regcache
*regcache
;
4578 /* Re-adjust PC to what the program would see if GDB was not
4580 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
4581 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4584 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4586 if (record_full_is_used ())
4587 record_full_gdb_operation_disable_set ();
4589 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
4591 do_cleanups (old_cleanups
);
4596 /* A delayed software breakpoint event. Ignore the trap. */
4598 fprintf_unfiltered (gdb_stdlog
,
4599 "infrun: delayed software breakpoint "
4600 "trap, ignoring\n");
4605 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
4606 has since been removed. */
4607 if (random_signal
&& target_stopped_by_hw_breakpoint ())
4609 /* A delayed hardware breakpoint event. Ignore the trap. */
4611 fprintf_unfiltered (gdb_stdlog
,
4612 "infrun: delayed hardware breakpoint/watchpoint "
4613 "trap, ignoring\n");
4617 /* If not, perhaps stepping/nexting can. */
4619 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4620 && currently_stepping (ecs
->event_thread
));
4622 /* Perhaps the thread hit a single-step breakpoint of _another_
4623 thread. Single-step breakpoints are transparent to the
4624 breakpoints module. */
4626 random_signal
= !ecs
->hit_singlestep_breakpoint
;
4628 /* No? Perhaps we got a moribund watchpoint. */
4630 random_signal
= !stopped_by_watchpoint
;
4632 /* For the program's own signals, act according to
4633 the signal handling tables. */
4637 /* Signal not for debugging purposes. */
4638 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
4639 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
4642 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
4643 gdb_signal_to_symbol_string (stop_signal
));
4645 stopped_by_random_signal
= 1;
4647 /* Always stop on signals if we're either just gaining control
4648 of the program, or the user explicitly requested this thread
4649 to remain stopped. */
4650 if (stop_soon
!= NO_STOP_QUIETLY
4651 || ecs
->event_thread
->stop_requested
4653 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4659 /* Notify observers the signal has "handle print" set. Note we
4660 returned early above if stopping; normal_stop handles the
4661 printing in that case. */
4662 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4664 /* The signal table tells us to print about this signal. */
4665 target_terminal_ours_for_output ();
4666 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
4667 target_terminal_inferior ();
4670 /* Clear the signal if it should not be passed. */
4671 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4672 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4674 if (ecs
->event_thread
->prev_pc
== stop_pc
4675 && ecs
->event_thread
->control
.trap_expected
4676 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4678 /* We were just starting a new sequence, attempting to
4679 single-step off of a breakpoint and expecting a SIGTRAP.
4680 Instead this signal arrives. This signal will take us out
4681 of the stepping range so GDB needs to remember to, when
4682 the signal handler returns, resume stepping off that
4684 /* To simplify things, "continue" is forced to use the same
4685 code paths as single-step - set a breakpoint at the
4686 signal return address and then, once hit, step off that
4689 fprintf_unfiltered (gdb_stdlog
,
4690 "infrun: signal arrived while stepping over "
4693 insert_hp_step_resume_breakpoint_at_frame (frame
);
4694 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4695 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4696 ecs
->event_thread
->control
.trap_expected
= 0;
4698 /* If we were nexting/stepping some other thread, switch to
4699 it, so that we don't continue it, losing control. */
4700 if (!switch_back_to_stepped_thread (ecs
))
4705 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4706 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4707 || ecs
->event_thread
->control
.step_range_end
== 1)
4708 && frame_id_eq (get_stack_frame_id (frame
),
4709 ecs
->event_thread
->control
.step_stack_frame_id
)
4710 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4712 /* The inferior is about to take a signal that will take it
4713 out of the single step range. Set a breakpoint at the
4714 current PC (which is presumably where the signal handler
4715 will eventually return) and then allow the inferior to
4718 Note that this is only needed for a signal delivered
4719 while in the single-step range. Nested signals aren't a
4720 problem as they eventually all return. */
4722 fprintf_unfiltered (gdb_stdlog
,
4723 "infrun: signal may take us out of "
4724 "single-step range\n");
4726 insert_hp_step_resume_breakpoint_at_frame (frame
);
4727 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4728 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4729 ecs
->event_thread
->control
.trap_expected
= 0;
4734 /* Note: step_resume_breakpoint may be non-NULL. This occures
4735 when either there's a nested signal, or when there's a
4736 pending signal enabled just as the signal handler returns
4737 (leaving the inferior at the step-resume-breakpoint without
4738 actually executing it). Either way continue until the
4739 breakpoint is really hit. */
4741 if (!switch_back_to_stepped_thread (ecs
))
4744 fprintf_unfiltered (gdb_stdlog
,
4745 "infrun: random signal, keep going\n");
4752 process_event_stop_test (ecs
);
4755 /* Come here when we've got some debug event / signal we can explain
4756 (IOW, not a random signal), and test whether it should cause a
4757 stop, or whether we should resume the inferior (transparently).
4758 E.g., could be a breakpoint whose condition evaluates false; we
4759 could be still stepping within the line; etc. */
4762 process_event_stop_test (struct execution_control_state
*ecs
)
4764 struct symtab_and_line stop_pc_sal
;
4765 struct frame_info
*frame
;
4766 struct gdbarch
*gdbarch
;
4767 CORE_ADDR jmp_buf_pc
;
4768 struct bpstat_what what
;
4770 /* Handle cases caused by hitting a breakpoint. */
4772 frame
= get_current_frame ();
4773 gdbarch
= get_frame_arch (frame
);
4775 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4777 if (what
.call_dummy
)
4779 stop_stack_dummy
= what
.call_dummy
;
4782 /* If we hit an internal event that triggers symbol changes, the
4783 current frame will be invalidated within bpstat_what (e.g., if we
4784 hit an internal solib event). Re-fetch it. */
4785 frame
= get_current_frame ();
4786 gdbarch
= get_frame_arch (frame
);
4788 switch (what
.main_action
)
4790 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4791 /* If we hit the breakpoint at longjmp while stepping, we
4792 install a momentary breakpoint at the target of the
4796 fprintf_unfiltered (gdb_stdlog
,
4797 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4799 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4801 if (what
.is_longjmp
)
4803 struct value
*arg_value
;
4805 /* If we set the longjmp breakpoint via a SystemTap probe,
4806 then use it to extract the arguments. The destination PC
4807 is the third argument to the probe. */
4808 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4811 jmp_buf_pc
= value_as_address (arg_value
);
4812 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
4814 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4815 || !gdbarch_get_longjmp_target (gdbarch
,
4816 frame
, &jmp_buf_pc
))
4819 fprintf_unfiltered (gdb_stdlog
,
4820 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4821 "(!gdbarch_get_longjmp_target)\n");
4826 /* Insert a breakpoint at resume address. */
4827 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4830 check_exception_resume (ecs
, frame
);
4834 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4836 struct frame_info
*init_frame
;
4838 /* There are several cases to consider.
4840 1. The initiating frame no longer exists. In this case we
4841 must stop, because the exception or longjmp has gone too
4844 2. The initiating frame exists, and is the same as the
4845 current frame. We stop, because the exception or longjmp
4848 3. The initiating frame exists and is different from the
4849 current frame. This means the exception or longjmp has
4850 been caught beneath the initiating frame, so keep going.
4852 4. longjmp breakpoint has been placed just to protect
4853 against stale dummy frames and user is not interested in
4854 stopping around longjmps. */
4857 fprintf_unfiltered (gdb_stdlog
,
4858 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4860 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4862 delete_exception_resume_breakpoint (ecs
->event_thread
);
4864 if (what
.is_longjmp
)
4866 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
4868 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
4876 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4880 struct frame_id current_id
4881 = get_frame_id (get_current_frame ());
4882 if (frame_id_eq (current_id
,
4883 ecs
->event_thread
->initiating_frame
))
4885 /* Case 2. Fall through. */
4895 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
4897 delete_step_resume_breakpoint (ecs
->event_thread
);
4899 end_stepping_range (ecs
);
4903 case BPSTAT_WHAT_SINGLE
:
4905 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4906 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4907 /* Still need to check other stuff, at least the case where we
4908 are stepping and step out of the right range. */
4911 case BPSTAT_WHAT_STEP_RESUME
:
4913 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4915 delete_step_resume_breakpoint (ecs
->event_thread
);
4916 if (ecs
->event_thread
->control
.proceed_to_finish
4917 && execution_direction
== EXEC_REVERSE
)
4919 struct thread_info
*tp
= ecs
->event_thread
;
4921 /* We are finishing a function in reverse, and just hit the
4922 step-resume breakpoint at the start address of the
4923 function, and we're almost there -- just need to back up
4924 by one more single-step, which should take us back to the
4926 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4930 fill_in_stop_func (gdbarch
, ecs
);
4931 if (stop_pc
== ecs
->stop_func_start
4932 && execution_direction
== EXEC_REVERSE
)
4934 /* We are stepping over a function call in reverse, and just
4935 hit the step-resume breakpoint at the start address of
4936 the function. Go back to single-stepping, which should
4937 take us back to the function call. */
4938 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4944 case BPSTAT_WHAT_STOP_NOISY
:
4946 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4947 stop_print_frame
= 1;
4949 /* Assume the thread stopped for a breapoint. We'll still check
4950 whether a/the breakpoint is there when the thread is next
4952 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4957 case BPSTAT_WHAT_STOP_SILENT
:
4959 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4960 stop_print_frame
= 0;
4962 /* Assume the thread stopped for a breapoint. We'll still check
4963 whether a/the breakpoint is there when the thread is next
4965 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4969 case BPSTAT_WHAT_HP_STEP_RESUME
:
4971 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4973 delete_step_resume_breakpoint (ecs
->event_thread
);
4974 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4976 /* Back when the step-resume breakpoint was inserted, we
4977 were trying to single-step off a breakpoint. Go back to
4979 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4980 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4986 case BPSTAT_WHAT_KEEP_CHECKING
:
4990 /* If we stepped a permanent breakpoint and we had a high priority
4991 step-resume breakpoint for the address we stepped, but we didn't
4992 hit it, then we must have stepped into the signal handler. The
4993 step-resume was only necessary to catch the case of _not_
4994 stepping into the handler, so delete it, and fall through to
4995 checking whether the step finished. */
4996 if (ecs
->event_thread
->stepped_breakpoint
)
4998 struct breakpoint
*sr_bp
4999 = ecs
->event_thread
->control
.step_resume_breakpoint
;
5002 && sr_bp
->loc
->permanent
5003 && sr_bp
->type
== bp_hp_step_resume
5004 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
5007 fprintf_unfiltered (gdb_stdlog
,
5008 "infrun: stepped permanent breakpoint, stopped in "
5010 delete_step_resume_breakpoint (ecs
->event_thread
);
5011 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
5015 /* We come here if we hit a breakpoint but should not stop for it.
5016 Possibly we also were stepping and should stop for that. So fall
5017 through and test for stepping. But, if not stepping, do not
5020 /* In all-stop mode, if we're currently stepping but have stopped in
5021 some other thread, we need to switch back to the stepped thread. */
5022 if (switch_back_to_stepped_thread (ecs
))
5025 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
5028 fprintf_unfiltered (gdb_stdlog
,
5029 "infrun: step-resume breakpoint is inserted\n");
5031 /* Having a step-resume breakpoint overrides anything
5032 else having to do with stepping commands until
5033 that breakpoint is reached. */
5038 if (ecs
->event_thread
->control
.step_range_end
== 0)
5041 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
5042 /* Likewise if we aren't even stepping. */
5047 /* Re-fetch current thread's frame in case the code above caused
5048 the frame cache to be re-initialized, making our FRAME variable
5049 a dangling pointer. */
5050 frame
= get_current_frame ();
5051 gdbarch
= get_frame_arch (frame
);
5052 fill_in_stop_func (gdbarch
, ecs
);
5054 /* If stepping through a line, keep going if still within it.
5056 Note that step_range_end is the address of the first instruction
5057 beyond the step range, and NOT the address of the last instruction
5060 Note also that during reverse execution, we may be stepping
5061 through a function epilogue and therefore must detect when
5062 the current-frame changes in the middle of a line. */
5064 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
5065 && (execution_direction
!= EXEC_REVERSE
5066 || frame_id_eq (get_frame_id (frame
),
5067 ecs
->event_thread
->control
.step_frame_id
)))
5071 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
5072 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
5073 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
5075 /* Tentatively re-enable range stepping; `resume' disables it if
5076 necessary (e.g., if we're stepping over a breakpoint or we
5077 have software watchpoints). */
5078 ecs
->event_thread
->control
.may_range_step
= 1;
5080 /* When stepping backward, stop at beginning of line range
5081 (unless it's the function entry point, in which case
5082 keep going back to the call point). */
5083 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
5084 && stop_pc
!= ecs
->stop_func_start
5085 && execution_direction
== EXEC_REVERSE
)
5086 end_stepping_range (ecs
);
5093 /* We stepped out of the stepping range. */
5095 /* If we are stepping at the source level and entered the runtime
5096 loader dynamic symbol resolution code...
5098 EXEC_FORWARD: we keep on single stepping until we exit the run
5099 time loader code and reach the callee's address.
5101 EXEC_REVERSE: we've already executed the callee (backward), and
5102 the runtime loader code is handled just like any other
5103 undebuggable function call. Now we need only keep stepping
5104 backward through the trampoline code, and that's handled further
5105 down, so there is nothing for us to do here. */
5107 if (execution_direction
!= EXEC_REVERSE
5108 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5109 && in_solib_dynsym_resolve_code (stop_pc
))
5111 CORE_ADDR pc_after_resolver
=
5112 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
5115 fprintf_unfiltered (gdb_stdlog
,
5116 "infrun: stepped into dynsym resolve code\n");
5118 if (pc_after_resolver
)
5120 /* Set up a step-resume breakpoint at the address
5121 indicated by SKIP_SOLIB_RESOLVER. */
5122 struct symtab_and_line sr_sal
;
5125 sr_sal
.pc
= pc_after_resolver
;
5126 sr_sal
.pspace
= get_frame_program_space (frame
);
5128 insert_step_resume_breakpoint_at_sal (gdbarch
,
5129 sr_sal
, null_frame_id
);
5136 if (ecs
->event_thread
->control
.step_range_end
!= 1
5137 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5138 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5139 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
5142 fprintf_unfiltered (gdb_stdlog
,
5143 "infrun: stepped into signal trampoline\n");
5144 /* The inferior, while doing a "step" or "next", has ended up in
5145 a signal trampoline (either by a signal being delivered or by
5146 the signal handler returning). Just single-step until the
5147 inferior leaves the trampoline (either by calling the handler
5153 /* If we're in the return path from a shared library trampoline,
5154 we want to proceed through the trampoline when stepping. */
5155 /* macro/2012-04-25: This needs to come before the subroutine
5156 call check below as on some targets return trampolines look
5157 like subroutine calls (MIPS16 return thunks). */
5158 if (gdbarch_in_solib_return_trampoline (gdbarch
,
5159 stop_pc
, ecs
->stop_func_name
)
5160 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5162 /* Determine where this trampoline returns. */
5163 CORE_ADDR real_stop_pc
;
5165 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
5168 fprintf_unfiltered (gdb_stdlog
,
5169 "infrun: stepped into solib return tramp\n");
5171 /* Only proceed through if we know where it's going. */
5174 /* And put the step-breakpoint there and go until there. */
5175 struct symtab_and_line sr_sal
;
5177 init_sal (&sr_sal
); /* initialize to zeroes */
5178 sr_sal
.pc
= real_stop_pc
;
5179 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5180 sr_sal
.pspace
= get_frame_program_space (frame
);
5182 /* Do not specify what the fp should be when we stop since
5183 on some machines the prologue is where the new fp value
5185 insert_step_resume_breakpoint_at_sal (gdbarch
,
5186 sr_sal
, null_frame_id
);
5188 /* Restart without fiddling with the step ranges or
5195 /* Check for subroutine calls. The check for the current frame
5196 equalling the step ID is not necessary - the check of the
5197 previous frame's ID is sufficient - but it is a common case and
5198 cheaper than checking the previous frame's ID.
5200 NOTE: frame_id_eq will never report two invalid frame IDs as
5201 being equal, so to get into this block, both the current and
5202 previous frame must have valid frame IDs. */
5203 /* The outer_frame_id check is a heuristic to detect stepping
5204 through startup code. If we step over an instruction which
5205 sets the stack pointer from an invalid value to a valid value,
5206 we may detect that as a subroutine call from the mythical
5207 "outermost" function. This could be fixed by marking
5208 outermost frames as !stack_p,code_p,special_p. Then the
5209 initial outermost frame, before sp was valid, would
5210 have code_addr == &_start. See the comment in frame_id_eq
5212 if (!frame_id_eq (get_stack_frame_id (frame
),
5213 ecs
->event_thread
->control
.step_stack_frame_id
)
5214 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
5215 ecs
->event_thread
->control
.step_stack_frame_id
)
5216 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
5218 || (ecs
->event_thread
->control
.step_start_function
5219 != find_pc_function (stop_pc
)))))
5221 CORE_ADDR real_stop_pc
;
5224 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
5226 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
5228 /* I presume that step_over_calls is only 0 when we're
5229 supposed to be stepping at the assembly language level
5230 ("stepi"). Just stop. */
5231 /* And this works the same backward as frontward. MVS */
5232 end_stepping_range (ecs
);
5236 /* Reverse stepping through solib trampolines. */
5238 if (execution_direction
== EXEC_REVERSE
5239 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
5240 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5241 || (ecs
->stop_func_start
== 0
5242 && in_solib_dynsym_resolve_code (stop_pc
))))
5244 /* Any solib trampoline code can be handled in reverse
5245 by simply continuing to single-step. We have already
5246 executed the solib function (backwards), and a few
5247 steps will take us back through the trampoline to the
5253 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5255 /* We're doing a "next".
5257 Normal (forward) execution: set a breakpoint at the
5258 callee's return address (the address at which the caller
5261 Reverse (backward) execution. set the step-resume
5262 breakpoint at the start of the function that we just
5263 stepped into (backwards), and continue to there. When we
5264 get there, we'll need to single-step back to the caller. */
5266 if (execution_direction
== EXEC_REVERSE
)
5268 /* If we're already at the start of the function, we've either
5269 just stepped backward into a single instruction function,
5270 or stepped back out of a signal handler to the first instruction
5271 of the function. Just keep going, which will single-step back
5273 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
5275 struct symtab_and_line sr_sal
;
5277 /* Normal function call return (static or dynamic). */
5279 sr_sal
.pc
= ecs
->stop_func_start
;
5280 sr_sal
.pspace
= get_frame_program_space (frame
);
5281 insert_step_resume_breakpoint_at_sal (gdbarch
,
5282 sr_sal
, null_frame_id
);
5286 insert_step_resume_breakpoint_at_caller (frame
);
5292 /* If we are in a function call trampoline (a stub between the
5293 calling routine and the real function), locate the real
5294 function. That's what tells us (a) whether we want to step
5295 into it at all, and (b) what prologue we want to run to the
5296 end of, if we do step into it. */
5297 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
5298 if (real_stop_pc
== 0)
5299 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
5300 if (real_stop_pc
!= 0)
5301 ecs
->stop_func_start
= real_stop_pc
;
5303 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
5305 struct symtab_and_line sr_sal
;
5308 sr_sal
.pc
= ecs
->stop_func_start
;
5309 sr_sal
.pspace
= get_frame_program_space (frame
);
5311 insert_step_resume_breakpoint_at_sal (gdbarch
,
5312 sr_sal
, null_frame_id
);
5317 /* If we have line number information for the function we are
5318 thinking of stepping into and the function isn't on the skip
5321 If there are several symtabs at that PC (e.g. with include
5322 files), just want to know whether *any* of them have line
5323 numbers. find_pc_line handles this. */
5325 struct symtab_and_line tmp_sal
;
5327 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5328 if (tmp_sal
.line
!= 0
5329 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
5332 if (execution_direction
== EXEC_REVERSE
)
5333 handle_step_into_function_backward (gdbarch
, ecs
);
5335 handle_step_into_function (gdbarch
, ecs
);
5340 /* If we have no line number and the step-stop-if-no-debug is
5341 set, we stop the step so that the user has a chance to switch
5342 in assembly mode. */
5343 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5344 && step_stop_if_no_debug
)
5346 end_stepping_range (ecs
);
5350 if (execution_direction
== EXEC_REVERSE
)
5352 /* If we're already at the start of the function, we've either just
5353 stepped backward into a single instruction function without line
5354 number info, or stepped back out of a signal handler to the first
5355 instruction of the function without line number info. Just keep
5356 going, which will single-step back to the caller. */
5357 if (ecs
->stop_func_start
!= stop_pc
)
5359 /* Set a breakpoint at callee's start address.
5360 From there we can step once and be back in the caller. */
5361 struct symtab_and_line sr_sal
;
5364 sr_sal
.pc
= ecs
->stop_func_start
;
5365 sr_sal
.pspace
= get_frame_program_space (frame
);
5366 insert_step_resume_breakpoint_at_sal (gdbarch
,
5367 sr_sal
, null_frame_id
);
5371 /* Set a breakpoint at callee's return address (the address
5372 at which the caller will resume). */
5373 insert_step_resume_breakpoint_at_caller (frame
);
5379 /* Reverse stepping through solib trampolines. */
5381 if (execution_direction
== EXEC_REVERSE
5382 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5384 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5385 || (ecs
->stop_func_start
== 0
5386 && in_solib_dynsym_resolve_code (stop_pc
)))
5388 /* Any solib trampoline code can be handled in reverse
5389 by simply continuing to single-step. We have already
5390 executed the solib function (backwards), and a few
5391 steps will take us back through the trampoline to the
5396 else if (in_solib_dynsym_resolve_code (stop_pc
))
5398 /* Stepped backward into the solib dynsym resolver.
5399 Set a breakpoint at its start and continue, then
5400 one more step will take us out. */
5401 struct symtab_and_line sr_sal
;
5404 sr_sal
.pc
= ecs
->stop_func_start
;
5405 sr_sal
.pspace
= get_frame_program_space (frame
);
5406 insert_step_resume_breakpoint_at_sal (gdbarch
,
5407 sr_sal
, null_frame_id
);
5413 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5415 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5416 the trampoline processing logic, however, there are some trampolines
5417 that have no names, so we should do trampoline handling first. */
5418 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5419 && ecs
->stop_func_name
== NULL
5420 && stop_pc_sal
.line
== 0)
5423 fprintf_unfiltered (gdb_stdlog
,
5424 "infrun: stepped into undebuggable function\n");
5426 /* The inferior just stepped into, or returned to, an
5427 undebuggable function (where there is no debugging information
5428 and no line number corresponding to the address where the
5429 inferior stopped). Since we want to skip this kind of code,
5430 we keep going until the inferior returns from this
5431 function - unless the user has asked us not to (via
5432 set step-mode) or we no longer know how to get back
5433 to the call site. */
5434 if (step_stop_if_no_debug
5435 || !frame_id_p (frame_unwind_caller_id (frame
)))
5437 /* If we have no line number and the step-stop-if-no-debug
5438 is set, we stop the step so that the user has a chance to
5439 switch in assembly mode. */
5440 end_stepping_range (ecs
);
5445 /* Set a breakpoint at callee's return address (the address
5446 at which the caller will resume). */
5447 insert_step_resume_breakpoint_at_caller (frame
);
5453 if (ecs
->event_thread
->control
.step_range_end
== 1)
5455 /* It is stepi or nexti. We always want to stop stepping after
5458 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5459 end_stepping_range (ecs
);
5463 if (stop_pc_sal
.line
== 0)
5465 /* We have no line number information. That means to stop
5466 stepping (does this always happen right after one instruction,
5467 when we do "s" in a function with no line numbers,
5468 or can this happen as a result of a return or longjmp?). */
5470 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5471 end_stepping_range (ecs
);
5475 /* Look for "calls" to inlined functions, part one. If the inline
5476 frame machinery detected some skipped call sites, we have entered
5477 a new inline function. */
5479 if (frame_id_eq (get_frame_id (get_current_frame ()),
5480 ecs
->event_thread
->control
.step_frame_id
)
5481 && inline_skipped_frames (ecs
->ptid
))
5483 struct symtab_and_line call_sal
;
5486 fprintf_unfiltered (gdb_stdlog
,
5487 "infrun: stepped into inlined function\n");
5489 find_frame_sal (get_current_frame (), &call_sal
);
5491 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5493 /* For "step", we're going to stop. But if the call site
5494 for this inlined function is on the same source line as
5495 we were previously stepping, go down into the function
5496 first. Otherwise stop at the call site. */
5498 if (call_sal
.line
== ecs
->event_thread
->current_line
5499 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5500 step_into_inline_frame (ecs
->ptid
);
5502 end_stepping_range (ecs
);
5507 /* For "next", we should stop at the call site if it is on a
5508 different source line. Otherwise continue through the
5509 inlined function. */
5510 if (call_sal
.line
== ecs
->event_thread
->current_line
5511 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5514 end_stepping_range (ecs
);
5519 /* Look for "calls" to inlined functions, part two. If we are still
5520 in the same real function we were stepping through, but we have
5521 to go further up to find the exact frame ID, we are stepping
5522 through a more inlined call beyond its call site. */
5524 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5525 && !frame_id_eq (get_frame_id (get_current_frame ()),
5526 ecs
->event_thread
->control
.step_frame_id
)
5527 && stepped_in_from (get_current_frame (),
5528 ecs
->event_thread
->control
.step_frame_id
))
5531 fprintf_unfiltered (gdb_stdlog
,
5532 "infrun: stepping through inlined function\n");
5534 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5537 end_stepping_range (ecs
);
5541 if ((stop_pc
== stop_pc_sal
.pc
)
5542 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5543 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5545 /* We are at the start of a different line. So stop. Note that
5546 we don't stop if we step into the middle of a different line.
5547 That is said to make things like for (;;) statements work
5550 fprintf_unfiltered (gdb_stdlog
,
5551 "infrun: stepped to a different line\n");
5552 end_stepping_range (ecs
);
5556 /* We aren't done stepping.
5558 Optimize by setting the stepping range to the line.
5559 (We might not be in the original line, but if we entered a
5560 new line in mid-statement, we continue stepping. This makes
5561 things like for(;;) statements work better.) */
5563 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5564 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5565 ecs
->event_thread
->control
.may_range_step
= 1;
5566 set_step_info (frame
, stop_pc_sal
);
5569 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5573 /* In all-stop mode, if we're currently stepping but have stopped in
5574 some other thread, we may need to switch back to the stepped
5575 thread. Returns true we set the inferior running, false if we left
5576 it stopped (and the event needs further processing). */
5579 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
5583 struct thread_info
*tp
;
5584 struct thread_info
*stepping_thread
;
5585 struct thread_info
*step_over
;
5587 /* If any thread is blocked on some internal breakpoint, and we
5588 simply need to step over that breakpoint to get it going
5589 again, do that first. */
5591 /* However, if we see an event for the stepping thread, then we
5592 know all other threads have been moved past their breakpoints
5593 already. Let the caller check whether the step is finished,
5594 etc., before deciding to move it past a breakpoint. */
5595 if (ecs
->event_thread
->control
.step_range_end
!= 0)
5598 /* Check if the current thread is blocked on an incomplete
5599 step-over, interrupted by a random signal. */
5600 if (ecs
->event_thread
->control
.trap_expected
5601 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5605 fprintf_unfiltered (gdb_stdlog
,
5606 "infrun: need to finish step-over of [%s]\n",
5607 target_pid_to_str (ecs
->event_thread
->ptid
));
5613 /* Check if the current thread is blocked by a single-step
5614 breakpoint of another thread. */
5615 if (ecs
->hit_singlestep_breakpoint
)
5619 fprintf_unfiltered (gdb_stdlog
,
5620 "infrun: need to step [%s] over single-step "
5622 target_pid_to_str (ecs
->ptid
));
5628 /* Otherwise, we no longer expect a trap in the current thread.
5629 Clear the trap_expected flag before switching back -- this is
5630 what keep_going does as well, if we call it. */
5631 ecs
->event_thread
->control
.trap_expected
= 0;
5633 /* Likewise, clear the signal if it should not be passed. */
5634 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5635 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5637 /* If scheduler locking applies even if not stepping, there's no
5638 need to walk over threads. Above we've checked whether the
5639 current thread is stepping. If some other thread not the
5640 event thread is stepping, then it must be that scheduler
5641 locking is not in effect. */
5642 if (schedlock_applies (ecs
->event_thread
))
5645 /* Look for the stepping/nexting thread, and check if any other
5646 thread other than the stepping thread needs to start a
5647 step-over. Do all step-overs before actually proceeding with
5649 stepping_thread
= NULL
;
5651 ALL_NON_EXITED_THREADS (tp
)
5653 /* Ignore threads of processes we're not resuming. */
5655 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
5658 /* When stepping over a breakpoint, we lock all threads
5659 except the one that needs to move past the breakpoint.
5660 If a non-event thread has this set, the "incomplete
5661 step-over" check above should have caught it earlier. */
5662 gdb_assert (!tp
->control
.trap_expected
);
5664 /* Did we find the stepping thread? */
5665 if (tp
->control
.step_range_end
)
5667 /* Yep. There should only one though. */
5668 gdb_assert (stepping_thread
== NULL
);
5670 /* The event thread is handled at the top, before we
5672 gdb_assert (tp
!= ecs
->event_thread
);
5674 /* If some thread other than the event thread is
5675 stepping, then scheduler locking can't be in effect,
5676 otherwise we wouldn't have resumed the current event
5677 thread in the first place. */
5678 gdb_assert (!schedlock_applies (tp
));
5680 stepping_thread
= tp
;
5682 else if (thread_still_needs_step_over (tp
))
5686 /* At the top we've returned early if the event thread
5687 is stepping. If some other thread not the event
5688 thread is stepping, then scheduler locking can't be
5689 in effect, and we can resume this thread. No need to
5690 keep looking for the stepping thread then. */
5695 if (step_over
!= NULL
)
5700 fprintf_unfiltered (gdb_stdlog
,
5701 "infrun: need to step-over [%s]\n",
5702 target_pid_to_str (tp
->ptid
));
5705 /* Only the stepping thread should have this set. */
5706 gdb_assert (tp
->control
.step_range_end
== 0);
5708 ecs
->ptid
= tp
->ptid
;
5709 ecs
->event_thread
= tp
;
5710 switch_to_thread (ecs
->ptid
);
5715 if (stepping_thread
!= NULL
)
5717 struct frame_info
*frame
;
5718 struct gdbarch
*gdbarch
;
5720 tp
= stepping_thread
;
5722 /* If the stepping thread exited, then don't try to switch
5723 back and resume it, which could fail in several different
5724 ways depending on the target. Instead, just keep going.
5726 We can find a stepping dead thread in the thread list in
5729 - The target supports thread exit events, and when the
5730 target tries to delete the thread from the thread list,
5731 inferior_ptid pointed at the exiting thread. In such
5732 case, calling delete_thread does not really remove the
5733 thread from the list; instead, the thread is left listed,
5734 with 'exited' state.
5736 - The target's debug interface does not support thread
5737 exit events, and so we have no idea whatsoever if the
5738 previously stepping thread is still alive. For that
5739 reason, we need to synchronously query the target
5741 if (is_exited (tp
->ptid
)
5742 || !target_thread_alive (tp
->ptid
))
5745 fprintf_unfiltered (gdb_stdlog
,
5746 "infrun: not switching back to "
5747 "stepped thread, it has vanished\n");
5749 delete_thread (tp
->ptid
);
5755 fprintf_unfiltered (gdb_stdlog
,
5756 "infrun: switching back to stepped thread\n");
5758 ecs
->event_thread
= tp
;
5759 ecs
->ptid
= tp
->ptid
;
5760 context_switch (ecs
->ptid
);
5762 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5763 frame
= get_current_frame ();
5764 gdbarch
= get_frame_arch (frame
);
5766 /* If the PC of the thread we were trying to single-step has
5767 changed, then that thread has trapped or been signaled,
5768 but the event has not been reported to GDB yet. Re-poll
5769 the target looking for this particular thread's event
5770 (i.e. temporarily enable schedlock) by:
5772 - setting a break at the current PC
5773 - resuming that particular thread, only (by setting
5776 This prevents us continuously moving the single-step
5777 breakpoint forward, one instruction at a time,
5780 if (stop_pc
!= tp
->prev_pc
)
5785 fprintf_unfiltered (gdb_stdlog
,
5786 "infrun: expected thread advanced also\n");
5788 /* Clear the info of the previous step-over, as it's no
5789 longer valid. It's what keep_going would do too, if
5790 we called it. Must do this before trying to insert
5791 the sss breakpoint, otherwise if we were previously
5792 trying to step over this exact address in another
5793 thread, the breakpoint ends up not installed. */
5794 clear_step_over_info ();
5796 insert_single_step_breakpoint (get_frame_arch (frame
),
5797 get_frame_address_space (frame
),
5800 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
5801 do_target_resume (resume_ptid
,
5802 currently_stepping (tp
), GDB_SIGNAL_0
);
5803 prepare_to_wait (ecs
);
5808 fprintf_unfiltered (gdb_stdlog
,
5809 "infrun: expected thread still "
5810 "hasn't advanced\n");
5820 /* Is thread TP in the middle of single-stepping? */
5823 currently_stepping (struct thread_info
*tp
)
5825 return ((tp
->control
.step_range_end
5826 && tp
->control
.step_resume_breakpoint
== NULL
)
5827 || tp
->control
.trap_expected
5828 || tp
->stepped_breakpoint
5829 || bpstat_should_step ());
5832 /* Inferior has stepped into a subroutine call with source code that
5833 we should not step over. Do step to the first line of code in
5837 handle_step_into_function (struct gdbarch
*gdbarch
,
5838 struct execution_control_state
*ecs
)
5840 struct compunit_symtab
*cust
;
5841 struct symtab_and_line stop_func_sal
, sr_sal
;
5843 fill_in_stop_func (gdbarch
, ecs
);
5845 cust
= find_pc_compunit_symtab (stop_pc
);
5846 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
5847 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5848 ecs
->stop_func_start
);
5850 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5851 /* Use the step_resume_break to step until the end of the prologue,
5852 even if that involves jumps (as it seems to on the vax under
5854 /* If the prologue ends in the middle of a source line, continue to
5855 the end of that source line (if it is still within the function).
5856 Otherwise, just go to end of prologue. */
5857 if (stop_func_sal
.end
5858 && stop_func_sal
.pc
!= ecs
->stop_func_start
5859 && stop_func_sal
.end
< ecs
->stop_func_end
)
5860 ecs
->stop_func_start
= stop_func_sal
.end
;
5862 /* Architectures which require breakpoint adjustment might not be able
5863 to place a breakpoint at the computed address. If so, the test
5864 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5865 ecs->stop_func_start to an address at which a breakpoint may be
5866 legitimately placed.
5868 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5869 made, GDB will enter an infinite loop when stepping through
5870 optimized code consisting of VLIW instructions which contain
5871 subinstructions corresponding to different source lines. On
5872 FR-V, it's not permitted to place a breakpoint on any but the
5873 first subinstruction of a VLIW instruction. When a breakpoint is
5874 set, GDB will adjust the breakpoint address to the beginning of
5875 the VLIW instruction. Thus, we need to make the corresponding
5876 adjustment here when computing the stop address. */
5878 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5880 ecs
->stop_func_start
5881 = gdbarch_adjust_breakpoint_address (gdbarch
,
5882 ecs
->stop_func_start
);
5885 if (ecs
->stop_func_start
== stop_pc
)
5887 /* We are already there: stop now. */
5888 end_stepping_range (ecs
);
5893 /* Put the step-breakpoint there and go until there. */
5894 init_sal (&sr_sal
); /* initialize to zeroes */
5895 sr_sal
.pc
= ecs
->stop_func_start
;
5896 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5897 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5899 /* Do not specify what the fp should be when we stop since on
5900 some machines the prologue is where the new fp value is
5902 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5904 /* And make sure stepping stops right away then. */
5905 ecs
->event_thread
->control
.step_range_end
5906 = ecs
->event_thread
->control
.step_range_start
;
5911 /* Inferior has stepped backward into a subroutine call with source
5912 code that we should not step over. Do step to the beginning of the
5913 last line of code in it. */
5916 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5917 struct execution_control_state
*ecs
)
5919 struct compunit_symtab
*cust
;
5920 struct symtab_and_line stop_func_sal
;
5922 fill_in_stop_func (gdbarch
, ecs
);
5924 cust
= find_pc_compunit_symtab (stop_pc
);
5925 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
5926 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5927 ecs
->stop_func_start
);
5929 stop_func_sal
= find_pc_line (stop_pc
, 0);
5931 /* OK, we're just going to keep stepping here. */
5932 if (stop_func_sal
.pc
== stop_pc
)
5934 /* We're there already. Just stop stepping now. */
5935 end_stepping_range (ecs
);
5939 /* Else just reset the step range and keep going.
5940 No step-resume breakpoint, they don't work for
5941 epilogues, which can have multiple entry paths. */
5942 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5943 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5949 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5950 This is used to both functions and to skip over code. */
5953 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5954 struct symtab_and_line sr_sal
,
5955 struct frame_id sr_id
,
5956 enum bptype sr_type
)
5958 /* There should never be more than one step-resume or longjmp-resume
5959 breakpoint per thread, so we should never be setting a new
5960 step_resume_breakpoint when one is already active. */
5961 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5962 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5965 fprintf_unfiltered (gdb_stdlog
,
5966 "infrun: inserting step-resume breakpoint at %s\n",
5967 paddress (gdbarch
, sr_sal
.pc
));
5969 inferior_thread ()->control
.step_resume_breakpoint
5970 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5974 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5975 struct symtab_and_line sr_sal
,
5976 struct frame_id sr_id
)
5978 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5983 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5984 This is used to skip a potential signal handler.
5986 This is called with the interrupted function's frame. The signal
5987 handler, when it returns, will resume the interrupted function at
5991 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5993 struct symtab_and_line sr_sal
;
5994 struct gdbarch
*gdbarch
;
5996 gdb_assert (return_frame
!= NULL
);
5997 init_sal (&sr_sal
); /* initialize to zeros */
5999 gdbarch
= get_frame_arch (return_frame
);
6000 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
6001 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6002 sr_sal
.pspace
= get_frame_program_space (return_frame
);
6004 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
6005 get_stack_frame_id (return_frame
),
6009 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
6010 is used to skip a function after stepping into it (for "next" or if
6011 the called function has no debugging information).
6013 The current function has almost always been reached by single
6014 stepping a call or return instruction. NEXT_FRAME belongs to the
6015 current function, and the breakpoint will be set at the caller's
6018 This is a separate function rather than reusing
6019 insert_hp_step_resume_breakpoint_at_frame in order to avoid
6020 get_prev_frame, which may stop prematurely (see the implementation
6021 of frame_unwind_caller_id for an example). */
6024 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
6026 struct symtab_and_line sr_sal
;
6027 struct gdbarch
*gdbarch
;
6029 /* We shouldn't have gotten here if we don't know where the call site
6031 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
6033 init_sal (&sr_sal
); /* initialize to zeros */
6035 gdbarch
= frame_unwind_caller_arch (next_frame
);
6036 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
6037 frame_unwind_caller_pc (next_frame
));
6038 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6039 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
6041 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
6042 frame_unwind_caller_id (next_frame
));
6045 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
6046 new breakpoint at the target of a jmp_buf. The handling of
6047 longjmp-resume uses the same mechanisms used for handling
6048 "step-resume" breakpoints. */
6051 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
6053 /* There should never be more than one longjmp-resume breakpoint per
6054 thread, so we should never be setting a new
6055 longjmp_resume_breakpoint when one is already active. */
6056 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
6059 fprintf_unfiltered (gdb_stdlog
,
6060 "infrun: inserting longjmp-resume breakpoint at %s\n",
6061 paddress (gdbarch
, pc
));
6063 inferior_thread ()->control
.exception_resume_breakpoint
=
6064 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
6067 /* Insert an exception resume breakpoint. TP is the thread throwing
6068 the exception. The block B is the block of the unwinder debug hook
6069 function. FRAME is the frame corresponding to the call to this
6070 function. SYM is the symbol of the function argument holding the
6071 target PC of the exception. */
6074 insert_exception_resume_breakpoint (struct thread_info
*tp
,
6075 const struct block
*b
,
6076 struct frame_info
*frame
,
6081 struct symbol
*vsym
;
6082 struct value
*value
;
6084 struct breakpoint
*bp
;
6086 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
6087 value
= read_var_value (vsym
, frame
);
6088 /* If the value was optimized out, revert to the old behavior. */
6089 if (! value_optimized_out (value
))
6091 handler
= value_as_address (value
);
6094 fprintf_unfiltered (gdb_stdlog
,
6095 "infrun: exception resume at %lx\n",
6096 (unsigned long) handler
);
6098 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
6099 handler
, bp_exception_resume
);
6101 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
6104 bp
->thread
= tp
->num
;
6105 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
6108 CATCH (e
, RETURN_MASK_ERROR
)
6110 /* We want to ignore errors here. */
6115 /* A helper for check_exception_resume that sets an
6116 exception-breakpoint based on a SystemTap probe. */
6119 insert_exception_resume_from_probe (struct thread_info
*tp
,
6120 const struct bound_probe
*probe
,
6121 struct frame_info
*frame
)
6123 struct value
*arg_value
;
6125 struct breakpoint
*bp
;
6127 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
6131 handler
= value_as_address (arg_value
);
6134 fprintf_unfiltered (gdb_stdlog
,
6135 "infrun: exception resume at %s\n",
6136 paddress (get_objfile_arch (probe
->objfile
),
6139 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
6140 handler
, bp_exception_resume
);
6141 bp
->thread
= tp
->num
;
6142 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
6145 /* This is called when an exception has been intercepted. Check to
6146 see whether the exception's destination is of interest, and if so,
6147 set an exception resume breakpoint there. */
6150 check_exception_resume (struct execution_control_state
*ecs
,
6151 struct frame_info
*frame
)
6153 struct bound_probe probe
;
6154 struct symbol
*func
;
6156 /* First see if this exception unwinding breakpoint was set via a
6157 SystemTap probe point. If so, the probe has two arguments: the
6158 CFA and the HANDLER. We ignore the CFA, extract the handler, and
6159 set a breakpoint there. */
6160 probe
= find_probe_by_pc (get_frame_pc (frame
));
6163 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
6167 func
= get_frame_function (frame
);
6173 const struct block
*b
;
6174 struct block_iterator iter
;
6178 /* The exception breakpoint is a thread-specific breakpoint on
6179 the unwinder's debug hook, declared as:
6181 void _Unwind_DebugHook (void *cfa, void *handler);
6183 The CFA argument indicates the frame to which control is
6184 about to be transferred. HANDLER is the destination PC.
6186 We ignore the CFA and set a temporary breakpoint at HANDLER.
6187 This is not extremely efficient but it avoids issues in gdb
6188 with computing the DWARF CFA, and it also works even in weird
6189 cases such as throwing an exception from inside a signal
6192 b
= SYMBOL_BLOCK_VALUE (func
);
6193 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
6195 if (!SYMBOL_IS_ARGUMENT (sym
))
6202 insert_exception_resume_breakpoint (ecs
->event_thread
,
6208 CATCH (e
, RETURN_MASK_ERROR
)
6215 stop_waiting (struct execution_control_state
*ecs
)
6218 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
6220 clear_step_over_info ();
6222 /* Let callers know we don't want to wait for the inferior anymore. */
6223 ecs
->wait_some_more
= 0;
6226 /* Called when we should continue running the inferior, because the
6227 current event doesn't cause a user visible stop. This does the
6228 resuming part; waiting for the next event is done elsewhere. */
6231 keep_going (struct execution_control_state
*ecs
)
6233 /* Make sure normal_stop is called if we get a QUIT handled before
6235 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
6237 /* Save the pc before execution, to compare with pc after stop. */
6238 ecs
->event_thread
->prev_pc
6239 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
6241 if (ecs
->event_thread
->control
.trap_expected
6242 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6244 /* We haven't yet gotten our trap, and either: intercepted a
6245 non-signal event (e.g., a fork); or took a signal which we
6246 are supposed to pass through to the inferior. Simply
6248 discard_cleanups (old_cleanups
);
6249 resume (ecs
->event_thread
->suspend
.stop_signal
);
6253 struct regcache
*regcache
= get_current_regcache ();
6257 /* Either the trap was not expected, but we are continuing
6258 anyway (if we got a signal, the user asked it be passed to
6261 We got our expected trap, but decided we should resume from
6264 We're going to run this baby now!
6266 Note that insert_breakpoints won't try to re-insert
6267 already inserted breakpoints. Therefore, we don't
6268 care if breakpoints were already inserted, or not. */
6270 /* If we need to step over a breakpoint, and we're not using
6271 displaced stepping to do so, insert all breakpoints
6272 (watchpoints, etc.) but the one we're stepping over, step one
6273 instruction, and then re-insert the breakpoint when that step
6276 remove_bp
= (ecs
->hit_singlestep_breakpoint
6277 || thread_still_needs_step_over (ecs
->event_thread
));
6278 remove_wps
= (ecs
->event_thread
->stepping_over_watchpoint
6279 && !target_have_steppable_watchpoint
);
6281 /* We can't use displaced stepping if we need to step past a
6282 watchpoint. The instruction copied to the scratch pad would
6283 still trigger the watchpoint. */
6286 || !use_displaced_stepping (get_regcache_arch (regcache
))))
6288 set_step_over_info (get_regcache_aspace (regcache
),
6289 regcache_read_pc (regcache
), remove_wps
);
6291 else if (remove_wps
)
6292 set_step_over_info (NULL
, 0, remove_wps
);
6294 clear_step_over_info ();
6296 /* Stop stepping if inserting breakpoints fails. */
6299 insert_breakpoints ();
6301 CATCH (e
, RETURN_MASK_ERROR
)
6303 exception_print (gdb_stderr
, e
);
6305 discard_cleanups (old_cleanups
);
6310 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
6312 /* Do not deliver GDB_SIGNAL_TRAP (except when the user
6313 explicitly specifies that such a signal should be delivered
6314 to the target program). Typically, that would occur when a
6315 user is debugging a target monitor on a simulator: the target
6316 monitor sets a breakpoint; the simulator encounters this
6317 breakpoint and halts the simulation handing control to GDB;
6318 GDB, noting that the stop address doesn't map to any known
6319 breakpoint, returns control back to the simulator; the
6320 simulator then delivers the hardware equivalent of a
6321 GDB_SIGNAL_TRAP to the program being debugged. */
6322 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6323 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6324 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6326 discard_cleanups (old_cleanups
);
6327 resume (ecs
->event_thread
->suspend
.stop_signal
);
6330 prepare_to_wait (ecs
);
6333 /* This function normally comes after a resume, before
6334 handle_inferior_event exits. It takes care of any last bits of
6335 housekeeping, and sets the all-important wait_some_more flag. */
6338 prepare_to_wait (struct execution_control_state
*ecs
)
6341 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
6343 /* This is the old end of the while loop. Let everybody know we
6344 want to wait for the inferior some more and get called again
6346 ecs
->wait_some_more
= 1;
6349 /* We are done with the step range of a step/next/si/ni command.
6350 Called once for each n of a "step n" operation. */
6353 end_stepping_range (struct execution_control_state
*ecs
)
6355 ecs
->event_thread
->control
.stop_step
= 1;
6359 /* Several print_*_reason functions to print why the inferior has stopped.
6360 We always print something when the inferior exits, or receives a signal.
6361 The rest of the cases are dealt with later on in normal_stop and
6362 print_it_typical. Ideally there should be a call to one of these
6363 print_*_reason functions functions from handle_inferior_event each time
6364 stop_waiting is called.
6366 Note that we don't call these directly, instead we delegate that to
6367 the interpreters, through observers. Interpreters then call these
6368 with whatever uiout is right. */
6371 print_end_stepping_range_reason (struct ui_out
*uiout
)
6373 /* For CLI-like interpreters, print nothing. */
6375 if (ui_out_is_mi_like_p (uiout
))
6377 ui_out_field_string (uiout
, "reason",
6378 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
6383 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6385 annotate_signalled ();
6386 if (ui_out_is_mi_like_p (uiout
))
6388 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
6389 ui_out_text (uiout
, "\nProgram terminated with signal ");
6390 annotate_signal_name ();
6391 ui_out_field_string (uiout
, "signal-name",
6392 gdb_signal_to_name (siggnal
));
6393 annotate_signal_name_end ();
6394 ui_out_text (uiout
, ", ");
6395 annotate_signal_string ();
6396 ui_out_field_string (uiout
, "signal-meaning",
6397 gdb_signal_to_string (siggnal
));
6398 annotate_signal_string_end ();
6399 ui_out_text (uiout
, ".\n");
6400 ui_out_text (uiout
, "The program no longer exists.\n");
6404 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
6406 struct inferior
*inf
= current_inferior ();
6407 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
6409 annotate_exited (exitstatus
);
6412 if (ui_out_is_mi_like_p (uiout
))
6413 ui_out_field_string (uiout
, "reason",
6414 async_reason_lookup (EXEC_ASYNC_EXITED
));
6415 ui_out_text (uiout
, "[Inferior ");
6416 ui_out_text (uiout
, plongest (inf
->num
));
6417 ui_out_text (uiout
, " (");
6418 ui_out_text (uiout
, pidstr
);
6419 ui_out_text (uiout
, ") exited with code ");
6420 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
6421 ui_out_text (uiout
, "]\n");
6425 if (ui_out_is_mi_like_p (uiout
))
6427 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
6428 ui_out_text (uiout
, "[Inferior ");
6429 ui_out_text (uiout
, plongest (inf
->num
));
6430 ui_out_text (uiout
, " (");
6431 ui_out_text (uiout
, pidstr
);
6432 ui_out_text (uiout
, ") exited normally]\n");
6437 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6441 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
6443 struct thread_info
*t
= inferior_thread ();
6445 ui_out_text (uiout
, "\n[");
6446 ui_out_field_string (uiout
, "thread-name",
6447 target_pid_to_str (t
->ptid
));
6448 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
6449 ui_out_text (uiout
, " stopped");
6453 ui_out_text (uiout
, "\nProgram received signal ");
6454 annotate_signal_name ();
6455 if (ui_out_is_mi_like_p (uiout
))
6457 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
6458 ui_out_field_string (uiout
, "signal-name",
6459 gdb_signal_to_name (siggnal
));
6460 annotate_signal_name_end ();
6461 ui_out_text (uiout
, ", ");
6462 annotate_signal_string ();
6463 ui_out_field_string (uiout
, "signal-meaning",
6464 gdb_signal_to_string (siggnal
));
6465 annotate_signal_string_end ();
6467 ui_out_text (uiout
, ".\n");
6471 print_no_history_reason (struct ui_out
*uiout
)
6473 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
6476 /* Print current location without a level number, if we have changed
6477 functions or hit a breakpoint. Print source line if we have one.
6478 bpstat_print contains the logic deciding in detail what to print,
6479 based on the event(s) that just occurred. */
6482 print_stop_event (struct target_waitstatus
*ws
)
6486 int do_frame_printing
= 1;
6487 struct thread_info
*tp
= inferior_thread ();
6489 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
6493 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
6494 should) carry around the function and does (or should) use
6495 that when doing a frame comparison. */
6496 if (tp
->control
.stop_step
6497 && frame_id_eq (tp
->control
.step_frame_id
,
6498 get_frame_id (get_current_frame ()))
6499 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
6501 /* Finished step, just print source line. */
6502 source_flag
= SRC_LINE
;
6506 /* Print location and source line. */
6507 source_flag
= SRC_AND_LOC
;
6510 case PRINT_SRC_AND_LOC
:
6511 /* Print location and source line. */
6512 source_flag
= SRC_AND_LOC
;
6514 case PRINT_SRC_ONLY
:
6515 source_flag
= SRC_LINE
;
6518 /* Something bogus. */
6519 source_flag
= SRC_LINE
;
6520 do_frame_printing
= 0;
6523 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6526 /* The behavior of this routine with respect to the source
6528 SRC_LINE: Print only source line
6529 LOCATION: Print only location
6530 SRC_AND_LOC: Print location and source line. */
6531 if (do_frame_printing
)
6532 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
6534 /* Display the auto-display expressions. */
6538 /* Here to return control to GDB when the inferior stops for real.
6539 Print appropriate messages, remove breakpoints, give terminal our modes.
6541 STOP_PRINT_FRAME nonzero means print the executing frame
6542 (pc, function, args, file, line number and line text).
6543 BREAKPOINTS_FAILED nonzero means stop was due to error
6544 attempting to insert breakpoints. */
6549 struct target_waitstatus last
;
6551 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
6553 get_last_target_status (&last_ptid
, &last
);
6555 /* If an exception is thrown from this point on, make sure to
6556 propagate GDB's knowledge of the executing state to the
6557 frontend/user running state. A QUIT is an easy exception to see
6558 here, so do this before any filtered output. */
6560 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
6561 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6562 && last
.kind
!= TARGET_WAITKIND_EXITED
6563 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6564 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
6566 /* As we're presenting a stop, and potentially removing breakpoints,
6567 update the thread list so we can tell whether there are threads
6568 running on the target. With target remote, for example, we can
6569 only learn about new threads when we explicitly update the thread
6570 list. Do this before notifying the interpreters about signal
6571 stops, end of stepping ranges, etc., so that the "new thread"
6572 output is emitted before e.g., "Program received signal FOO",
6573 instead of after. */
6574 update_thread_list ();
6576 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
6577 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
6579 /* As with the notification of thread events, we want to delay
6580 notifying the user that we've switched thread context until
6581 the inferior actually stops.
6583 There's no point in saying anything if the inferior has exited.
6584 Note that SIGNALLED here means "exited with a signal", not
6585 "received a signal".
6587 Also skip saying anything in non-stop mode. In that mode, as we
6588 don't want GDB to switch threads behind the user's back, to avoid
6589 races where the user is typing a command to apply to thread x,
6590 but GDB switches to thread y before the user finishes entering
6591 the command, fetch_inferior_event installs a cleanup to restore
6592 the current thread back to the thread the user had selected right
6593 after this event is handled, so we're not really switching, only
6594 informing of a stop. */
6596 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
6597 && target_has_execution
6598 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6599 && last
.kind
!= TARGET_WAITKIND_EXITED
6600 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6602 target_terminal_ours_for_output ();
6603 printf_filtered (_("[Switching to %s]\n"),
6604 target_pid_to_str (inferior_ptid
));
6605 annotate_thread_changed ();
6606 previous_inferior_ptid
= inferior_ptid
;
6609 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
6611 gdb_assert (sync_execution
|| !target_can_async_p ());
6613 target_terminal_ours_for_output ();
6614 printf_filtered (_("No unwaited-for children left.\n"));
6617 /* Note: this depends on the update_thread_list call above. */
6618 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
6620 if (remove_breakpoints ())
6622 target_terminal_ours_for_output ();
6623 printf_filtered (_("Cannot remove breakpoints because "
6624 "program is no longer writable.\nFurther "
6625 "execution is probably impossible.\n"));
6629 /* If an auto-display called a function and that got a signal,
6630 delete that auto-display to avoid an infinite recursion. */
6632 if (stopped_by_random_signal
)
6633 disable_current_display ();
6635 /* Notify observers if we finished a "step"-like command, etc. */
6636 if (target_has_execution
6637 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6638 && last
.kind
!= TARGET_WAITKIND_EXITED
6639 && inferior_thread ()->control
.stop_step
)
6641 /* But not if in the middle of doing a "step n" operation for
6643 if (inferior_thread ()->step_multi
)
6646 observer_notify_end_stepping_range ();
6649 target_terminal_ours ();
6650 async_enable_stdin ();
6652 /* Set the current source location. This will also happen if we
6653 display the frame below, but the current SAL will be incorrect
6654 during a user hook-stop function. */
6655 if (has_stack_frames () && !stop_stack_dummy
)
6656 set_current_sal_from_frame (get_current_frame ());
6658 /* Let the user/frontend see the threads as stopped, but do nothing
6659 if the thread was running an infcall. We may be e.g., evaluating
6660 a breakpoint condition. In that case, the thread had state
6661 THREAD_RUNNING before the infcall, and shall remain set to
6662 running, all without informing the user/frontend about state
6663 transition changes. If this is actually a call command, then the
6664 thread was originally already stopped, so there's no state to
6666 if (target_has_execution
&& inferior_thread ()->control
.in_infcall
)
6667 discard_cleanups (old_chain
);
6669 do_cleanups (old_chain
);
6671 /* Look up the hook_stop and run it (CLI internally handles problem
6672 of stop_command's pre-hook not existing). */
6674 catch_errors (hook_stop_stub
, stop_command
,
6675 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
6677 if (!has_stack_frames ())
6680 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
6681 || last
.kind
== TARGET_WAITKIND_EXITED
)
6684 /* Select innermost stack frame - i.e., current frame is frame 0,
6685 and current location is based on that.
6686 Don't do this on return from a stack dummy routine,
6687 or if the program has exited. */
6689 if (!stop_stack_dummy
)
6691 select_frame (get_current_frame ());
6693 /* If --batch-silent is enabled then there's no need to print the current
6694 source location, and to try risks causing an error message about
6695 missing source files. */
6696 if (stop_print_frame
&& !batch_silent
)
6697 print_stop_event (&last
);
6700 /* Save the function value return registers, if we care.
6701 We might be about to restore their previous contents. */
6702 if (inferior_thread ()->control
.proceed_to_finish
6703 && execution_direction
!= EXEC_REVERSE
)
6705 /* This should not be necessary. */
6707 regcache_xfree (stop_registers
);
6709 /* NB: The copy goes through to the target picking up the value of
6710 all the registers. */
6711 stop_registers
= regcache_dup (get_current_regcache ());
6714 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6716 /* Pop the empty frame that contains the stack dummy.
6717 This also restores inferior state prior to the call
6718 (struct infcall_suspend_state). */
6719 struct frame_info
*frame
= get_current_frame ();
6721 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6723 /* frame_pop() calls reinit_frame_cache as the last thing it
6724 does which means there's currently no selected frame. We
6725 don't need to re-establish a selected frame if the dummy call
6726 returns normally, that will be done by
6727 restore_infcall_control_state. However, we do have to handle
6728 the case where the dummy call is returning after being
6729 stopped (e.g. the dummy call previously hit a breakpoint).
6730 We can't know which case we have so just always re-establish
6731 a selected frame here. */
6732 select_frame (get_current_frame ());
6736 annotate_stopped ();
6738 /* Suppress the stop observer if we're in the middle of:
6740 - a step n (n > 1), as there still more steps to be done.
6742 - a "finish" command, as the observer will be called in
6743 finish_command_continuation, so it can include the inferior
6744 function's return value.
6746 - calling an inferior function, as we pretend we inferior didn't
6747 run at all. The return value of the call is handled by the
6748 expression evaluator, through call_function_by_hand. */
6750 if (!target_has_execution
6751 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6752 || last
.kind
== TARGET_WAITKIND_EXITED
6753 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6754 || (!(inferior_thread ()->step_multi
6755 && inferior_thread ()->control
.stop_step
)
6756 && !(inferior_thread ()->control
.stop_bpstat
6757 && inferior_thread ()->control
.proceed_to_finish
)
6758 && !inferior_thread ()->control
.in_infcall
))
6760 if (!ptid_equal (inferior_ptid
, null_ptid
))
6761 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6764 observer_notify_normal_stop (NULL
, stop_print_frame
);
6767 if (target_has_execution
)
6769 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6770 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6771 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6772 Delete any breakpoint that is to be deleted at the next stop. */
6773 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6776 /* Try to get rid of automatically added inferiors that are no
6777 longer needed. Keeping those around slows down things linearly.
6778 Note that this never removes the current inferior. */
6783 hook_stop_stub (void *cmd
)
6785 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6790 signal_stop_state (int signo
)
6792 return signal_stop
[signo
];
6796 signal_print_state (int signo
)
6798 return signal_print
[signo
];
6802 signal_pass_state (int signo
)
6804 return signal_program
[signo
];
6808 signal_cache_update (int signo
)
6812 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6813 signal_cache_update (signo
);
6818 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6819 && signal_print
[signo
] == 0
6820 && signal_program
[signo
] == 1
6821 && signal_catch
[signo
] == 0);
6825 signal_stop_update (int signo
, int state
)
6827 int ret
= signal_stop
[signo
];
6829 signal_stop
[signo
] = state
;
6830 signal_cache_update (signo
);
6835 signal_print_update (int signo
, int state
)
6837 int ret
= signal_print
[signo
];
6839 signal_print
[signo
] = state
;
6840 signal_cache_update (signo
);
6845 signal_pass_update (int signo
, int state
)
6847 int ret
= signal_program
[signo
];
6849 signal_program
[signo
] = state
;
6850 signal_cache_update (signo
);
6854 /* Update the global 'signal_catch' from INFO and notify the
6858 signal_catch_update (const unsigned int *info
)
6862 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
6863 signal_catch
[i
] = info
[i
] > 0;
6864 signal_cache_update (-1);
6865 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6869 sig_print_header (void)
6871 printf_filtered (_("Signal Stop\tPrint\tPass "
6872 "to program\tDescription\n"));
6876 sig_print_info (enum gdb_signal oursig
)
6878 const char *name
= gdb_signal_to_name (oursig
);
6879 int name_padding
= 13 - strlen (name
);
6881 if (name_padding
<= 0)
6884 printf_filtered ("%s", name
);
6885 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6886 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6887 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6888 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6889 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6892 /* Specify how various signals in the inferior should be handled. */
6895 handle_command (char *args
, int from_tty
)
6898 int digits
, wordlen
;
6899 int sigfirst
, signum
, siglast
;
6900 enum gdb_signal oursig
;
6903 unsigned char *sigs
;
6904 struct cleanup
*old_chain
;
6908 error_no_arg (_("signal to handle"));
6911 /* Allocate and zero an array of flags for which signals to handle. */
6913 nsigs
= (int) GDB_SIGNAL_LAST
;
6914 sigs
= (unsigned char *) alloca (nsigs
);
6915 memset (sigs
, 0, nsigs
);
6917 /* Break the command line up into args. */
6919 argv
= gdb_buildargv (args
);
6920 old_chain
= make_cleanup_freeargv (argv
);
6922 /* Walk through the args, looking for signal oursigs, signal names, and
6923 actions. Signal numbers and signal names may be interspersed with
6924 actions, with the actions being performed for all signals cumulatively
6925 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6927 while (*argv
!= NULL
)
6929 wordlen
= strlen (*argv
);
6930 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6934 sigfirst
= siglast
= -1;
6936 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6938 /* Apply action to all signals except those used by the
6939 debugger. Silently skip those. */
6942 siglast
= nsigs
- 1;
6944 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6946 SET_SIGS (nsigs
, sigs
, signal_stop
);
6947 SET_SIGS (nsigs
, sigs
, signal_print
);
6949 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6951 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6953 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6955 SET_SIGS (nsigs
, sigs
, signal_print
);
6957 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6959 SET_SIGS (nsigs
, sigs
, signal_program
);
6961 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6963 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6965 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6967 SET_SIGS (nsigs
, sigs
, signal_program
);
6969 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6971 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6972 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6974 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6976 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6978 else if (digits
> 0)
6980 /* It is numeric. The numeric signal refers to our own
6981 internal signal numbering from target.h, not to host/target
6982 signal number. This is a feature; users really should be
6983 using symbolic names anyway, and the common ones like
6984 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6986 sigfirst
= siglast
= (int)
6987 gdb_signal_from_command (atoi (*argv
));
6988 if ((*argv
)[digits
] == '-')
6991 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6993 if (sigfirst
> siglast
)
6995 /* Bet he didn't figure we'd think of this case... */
7003 oursig
= gdb_signal_from_name (*argv
);
7004 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
7006 sigfirst
= siglast
= (int) oursig
;
7010 /* Not a number and not a recognized flag word => complain. */
7011 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
7015 /* If any signal numbers or symbol names were found, set flags for
7016 which signals to apply actions to. */
7018 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
7020 switch ((enum gdb_signal
) signum
)
7022 case GDB_SIGNAL_TRAP
:
7023 case GDB_SIGNAL_INT
:
7024 if (!allsigs
&& !sigs
[signum
])
7026 if (query (_("%s is used by the debugger.\n\
7027 Are you sure you want to change it? "),
7028 gdb_signal_to_name ((enum gdb_signal
) signum
)))
7034 printf_unfiltered (_("Not confirmed, unchanged.\n"));
7035 gdb_flush (gdb_stdout
);
7040 case GDB_SIGNAL_DEFAULT
:
7041 case GDB_SIGNAL_UNKNOWN
:
7042 /* Make sure that "all" doesn't print these. */
7053 for (signum
= 0; signum
< nsigs
; signum
++)
7056 signal_cache_update (-1);
7057 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
7058 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
7062 /* Show the results. */
7063 sig_print_header ();
7064 for (; signum
< nsigs
; signum
++)
7066 sig_print_info (signum
);
7072 do_cleanups (old_chain
);
7075 /* Complete the "handle" command. */
7077 static VEC (char_ptr
) *
7078 handle_completer (struct cmd_list_element
*ignore
,
7079 const char *text
, const char *word
)
7081 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
7082 static const char * const keywords
[] =
7096 vec_signals
= signal_completer (ignore
, text
, word
);
7097 vec_keywords
= complete_on_enum (keywords
, word
, word
);
7099 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
7100 VEC_free (char_ptr
, vec_signals
);
7101 VEC_free (char_ptr
, vec_keywords
);
7106 gdb_signal_from_command (int num
)
7108 if (num
>= 1 && num
<= 15)
7109 return (enum gdb_signal
) num
;
7110 error (_("Only signals 1-15 are valid as numeric signals.\n\
7111 Use \"info signals\" for a list of symbolic signals."));
7114 /* Print current contents of the tables set by the handle command.
7115 It is possible we should just be printing signals actually used
7116 by the current target (but for things to work right when switching
7117 targets, all signals should be in the signal tables). */
7120 signals_info (char *signum_exp
, int from_tty
)
7122 enum gdb_signal oursig
;
7124 sig_print_header ();
7128 /* First see if this is a symbol name. */
7129 oursig
= gdb_signal_from_name (signum_exp
);
7130 if (oursig
== GDB_SIGNAL_UNKNOWN
)
7132 /* No, try numeric. */
7134 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
7136 sig_print_info (oursig
);
7140 printf_filtered ("\n");
7141 /* These ugly casts brought to you by the native VAX compiler. */
7142 for (oursig
= GDB_SIGNAL_FIRST
;
7143 (int) oursig
< (int) GDB_SIGNAL_LAST
;
7144 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
7148 if (oursig
!= GDB_SIGNAL_UNKNOWN
7149 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
7150 sig_print_info (oursig
);
7153 printf_filtered (_("\nUse the \"handle\" command "
7154 "to change these tables.\n"));
7157 /* Check if it makes sense to read $_siginfo from the current thread
7158 at this point. If not, throw an error. */
7161 validate_siginfo_access (void)
7163 /* No current inferior, no siginfo. */
7164 if (ptid_equal (inferior_ptid
, null_ptid
))
7165 error (_("No thread selected."));
7167 /* Don't try to read from a dead thread. */
7168 if (is_exited (inferior_ptid
))
7169 error (_("The current thread has terminated"));
7171 /* ... or from a spinning thread. */
7172 if (is_running (inferior_ptid
))
7173 error (_("Selected thread is running."));
7176 /* The $_siginfo convenience variable is a bit special. We don't know
7177 for sure the type of the value until we actually have a chance to
7178 fetch the data. The type can change depending on gdbarch, so it is
7179 also dependent on which thread you have selected.
7181 1. making $_siginfo be an internalvar that creates a new value on
7184 2. making the value of $_siginfo be an lval_computed value. */
7186 /* This function implements the lval_computed support for reading a
7190 siginfo_value_read (struct value
*v
)
7192 LONGEST transferred
;
7194 validate_siginfo_access ();
7197 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
7199 value_contents_all_raw (v
),
7201 TYPE_LENGTH (value_type (v
)));
7203 if (transferred
!= TYPE_LENGTH (value_type (v
)))
7204 error (_("Unable to read siginfo"));
7207 /* This function implements the lval_computed support for writing a
7211 siginfo_value_write (struct value
*v
, struct value
*fromval
)
7213 LONGEST transferred
;
7215 validate_siginfo_access ();
7217 transferred
= target_write (¤t_target
,
7218 TARGET_OBJECT_SIGNAL_INFO
,
7220 value_contents_all_raw (fromval
),
7222 TYPE_LENGTH (value_type (fromval
)));
7224 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
7225 error (_("Unable to write siginfo"));
7228 static const struct lval_funcs siginfo_value_funcs
=
7234 /* Return a new value with the correct type for the siginfo object of
7235 the current thread using architecture GDBARCH. Return a void value
7236 if there's no object available. */
7238 static struct value
*
7239 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
7242 if (target_has_stack
7243 && !ptid_equal (inferior_ptid
, null_ptid
)
7244 && gdbarch_get_siginfo_type_p (gdbarch
))
7246 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7248 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
7251 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
7255 /* infcall_suspend_state contains state about the program itself like its
7256 registers and any signal it received when it last stopped.
7257 This state must be restored regardless of how the inferior function call
7258 ends (either successfully, or after it hits a breakpoint or signal)
7259 if the program is to properly continue where it left off. */
7261 struct infcall_suspend_state
7263 struct thread_suspend_state thread_suspend
;
7264 #if 0 /* Currently unused and empty structures are not valid C. */
7265 struct inferior_suspend_state inferior_suspend
;
7270 struct regcache
*registers
;
7272 /* Format of SIGINFO_DATA or NULL if it is not present. */
7273 struct gdbarch
*siginfo_gdbarch
;
7275 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
7276 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
7277 content would be invalid. */
7278 gdb_byte
*siginfo_data
;
7281 struct infcall_suspend_state
*
7282 save_infcall_suspend_state (void)
7284 struct infcall_suspend_state
*inf_state
;
7285 struct thread_info
*tp
= inferior_thread ();
7287 struct inferior
*inf
= current_inferior ();
7289 struct regcache
*regcache
= get_current_regcache ();
7290 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7291 gdb_byte
*siginfo_data
= NULL
;
7293 if (gdbarch_get_siginfo_type_p (gdbarch
))
7295 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7296 size_t len
= TYPE_LENGTH (type
);
7297 struct cleanup
*back_to
;
7299 siginfo_data
= xmalloc (len
);
7300 back_to
= make_cleanup (xfree
, siginfo_data
);
7302 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7303 siginfo_data
, 0, len
) == len
)
7304 discard_cleanups (back_to
);
7307 /* Errors ignored. */
7308 do_cleanups (back_to
);
7309 siginfo_data
= NULL
;
7313 inf_state
= XCNEW (struct infcall_suspend_state
);
7317 inf_state
->siginfo_gdbarch
= gdbarch
;
7318 inf_state
->siginfo_data
= siginfo_data
;
7321 inf_state
->thread_suspend
= tp
->suspend
;
7322 #if 0 /* Currently unused and empty structures are not valid C. */
7323 inf_state
->inferior_suspend
= inf
->suspend
;
7326 /* run_inferior_call will not use the signal due to its `proceed' call with
7327 GDB_SIGNAL_0 anyway. */
7328 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7330 inf_state
->stop_pc
= stop_pc
;
7332 inf_state
->registers
= regcache_dup (regcache
);
7337 /* Restore inferior session state to INF_STATE. */
7340 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7342 struct thread_info
*tp
= inferior_thread ();
7344 struct inferior
*inf
= current_inferior ();
7346 struct regcache
*regcache
= get_current_regcache ();
7347 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7349 tp
->suspend
= inf_state
->thread_suspend
;
7350 #if 0 /* Currently unused and empty structures are not valid C. */
7351 inf
->suspend
= inf_state
->inferior_suspend
;
7354 stop_pc
= inf_state
->stop_pc
;
7356 if (inf_state
->siginfo_gdbarch
== gdbarch
)
7358 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7360 /* Errors ignored. */
7361 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7362 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
7365 /* The inferior can be gone if the user types "print exit(0)"
7366 (and perhaps other times). */
7367 if (target_has_execution
)
7368 /* NB: The register write goes through to the target. */
7369 regcache_cpy (regcache
, inf_state
->registers
);
7371 discard_infcall_suspend_state (inf_state
);
7375 do_restore_infcall_suspend_state_cleanup (void *state
)
7377 restore_infcall_suspend_state (state
);
7381 make_cleanup_restore_infcall_suspend_state
7382 (struct infcall_suspend_state
*inf_state
)
7384 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
7388 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7390 regcache_xfree (inf_state
->registers
);
7391 xfree (inf_state
->siginfo_data
);
7396 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
7398 return inf_state
->registers
;
7401 /* infcall_control_state contains state regarding gdb's control of the
7402 inferior itself like stepping control. It also contains session state like
7403 the user's currently selected frame. */
7405 struct infcall_control_state
7407 struct thread_control_state thread_control
;
7408 struct inferior_control_state inferior_control
;
7411 enum stop_stack_kind stop_stack_dummy
;
7412 int stopped_by_random_signal
;
7413 int stop_after_trap
;
7415 /* ID if the selected frame when the inferior function call was made. */
7416 struct frame_id selected_frame_id
;
7419 /* Save all of the information associated with the inferior<==>gdb
7422 struct infcall_control_state
*
7423 save_infcall_control_state (void)
7425 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
7426 struct thread_info
*tp
= inferior_thread ();
7427 struct inferior
*inf
= current_inferior ();
7429 inf_status
->thread_control
= tp
->control
;
7430 inf_status
->inferior_control
= inf
->control
;
7432 tp
->control
.step_resume_breakpoint
= NULL
;
7433 tp
->control
.exception_resume_breakpoint
= NULL
;
7435 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
7436 chain. If caller's caller is walking the chain, they'll be happier if we
7437 hand them back the original chain when restore_infcall_control_state is
7439 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
7442 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
7443 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
7444 inf_status
->stop_after_trap
= stop_after_trap
;
7446 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
7452 restore_selected_frame (void *args
)
7454 struct frame_id
*fid
= (struct frame_id
*) args
;
7455 struct frame_info
*frame
;
7457 frame
= frame_find_by_id (*fid
);
7459 /* If inf_status->selected_frame_id is NULL, there was no previously
7463 warning (_("Unable to restore previously selected frame."));
7467 select_frame (frame
);
7472 /* Restore inferior session state to INF_STATUS. */
7475 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
7477 struct thread_info
*tp
= inferior_thread ();
7478 struct inferior
*inf
= current_inferior ();
7480 if (tp
->control
.step_resume_breakpoint
)
7481 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
7483 if (tp
->control
.exception_resume_breakpoint
)
7484 tp
->control
.exception_resume_breakpoint
->disposition
7485 = disp_del_at_next_stop
;
7487 /* Handle the bpstat_copy of the chain. */
7488 bpstat_clear (&tp
->control
.stop_bpstat
);
7490 tp
->control
= inf_status
->thread_control
;
7491 inf
->control
= inf_status
->inferior_control
;
7494 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
7495 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
7496 stop_after_trap
= inf_status
->stop_after_trap
;
7498 if (target_has_stack
)
7500 /* The point of catch_errors is that if the stack is clobbered,
7501 walking the stack might encounter a garbage pointer and
7502 error() trying to dereference it. */
7504 (restore_selected_frame
, &inf_status
->selected_frame_id
,
7505 "Unable to restore previously selected frame:\n",
7506 RETURN_MASK_ERROR
) == 0)
7507 /* Error in restoring the selected frame. Select the innermost
7509 select_frame (get_current_frame ());
7516 do_restore_infcall_control_state_cleanup (void *sts
)
7518 restore_infcall_control_state (sts
);
7522 make_cleanup_restore_infcall_control_state
7523 (struct infcall_control_state
*inf_status
)
7525 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
7529 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
7531 if (inf_status
->thread_control
.step_resume_breakpoint
)
7532 inf_status
->thread_control
.step_resume_breakpoint
->disposition
7533 = disp_del_at_next_stop
;
7535 if (inf_status
->thread_control
.exception_resume_breakpoint
)
7536 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
7537 = disp_del_at_next_stop
;
7539 /* See save_infcall_control_state for info on stop_bpstat. */
7540 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
7545 /* restore_inferior_ptid() will be used by the cleanup machinery
7546 to restore the inferior_ptid value saved in a call to
7547 save_inferior_ptid(). */
7550 restore_inferior_ptid (void *arg
)
7552 ptid_t
*saved_ptid_ptr
= arg
;
7554 inferior_ptid
= *saved_ptid_ptr
;
7558 /* Save the value of inferior_ptid so that it may be restored by a
7559 later call to do_cleanups(). Returns the struct cleanup pointer
7560 needed for later doing the cleanup. */
7563 save_inferior_ptid (void)
7565 ptid_t
*saved_ptid_ptr
;
7567 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
7568 *saved_ptid_ptr
= inferior_ptid
;
7569 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
7575 clear_exit_convenience_vars (void)
7577 clear_internalvar (lookup_internalvar ("_exitsignal"));
7578 clear_internalvar (lookup_internalvar ("_exitcode"));
7582 /* User interface for reverse debugging:
7583 Set exec-direction / show exec-direction commands
7584 (returns error unless target implements to_set_exec_direction method). */
7586 int execution_direction
= EXEC_FORWARD
;
7587 static const char exec_forward
[] = "forward";
7588 static const char exec_reverse
[] = "reverse";
7589 static const char *exec_direction
= exec_forward
;
7590 static const char *const exec_direction_names
[] = {
7597 set_exec_direction_func (char *args
, int from_tty
,
7598 struct cmd_list_element
*cmd
)
7600 if (target_can_execute_reverse
)
7602 if (!strcmp (exec_direction
, exec_forward
))
7603 execution_direction
= EXEC_FORWARD
;
7604 else if (!strcmp (exec_direction
, exec_reverse
))
7605 execution_direction
= EXEC_REVERSE
;
7609 exec_direction
= exec_forward
;
7610 error (_("Target does not support this operation."));
7615 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7616 struct cmd_list_element
*cmd
, const char *value
)
7618 switch (execution_direction
) {
7620 fprintf_filtered (out
, _("Forward.\n"));
7623 fprintf_filtered (out
, _("Reverse.\n"));
7626 internal_error (__FILE__
, __LINE__
,
7627 _("bogus execution_direction value: %d"),
7628 (int) execution_direction
);
7633 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7634 struct cmd_list_element
*c
, const char *value
)
7636 fprintf_filtered (file
, _("Resuming the execution of threads "
7637 "of all processes is %s.\n"), value
);
7640 /* Implementation of `siginfo' variable. */
7642 static const struct internalvar_funcs siginfo_funcs
=
7650 _initialize_infrun (void)
7654 struct cmd_list_element
*c
;
7656 add_info ("signals", signals_info
, _("\
7657 What debugger does when program gets various signals.\n\
7658 Specify a signal as argument to print info on that signal only."));
7659 add_info_alias ("handle", "signals", 0);
7661 c
= add_com ("handle", class_run
, handle_command
, _("\
7662 Specify how to handle signals.\n\
7663 Usage: handle SIGNAL [ACTIONS]\n\
7664 Args are signals and actions to apply to those signals.\n\
7665 If no actions are specified, the current settings for the specified signals\n\
7666 will be displayed instead.\n\
7668 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7669 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7670 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7671 The special arg \"all\" is recognized to mean all signals except those\n\
7672 used by the debugger, typically SIGTRAP and SIGINT.\n\
7674 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7675 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7676 Stop means reenter debugger if this signal happens (implies print).\n\
7677 Print means print a message if this signal happens.\n\
7678 Pass means let program see this signal; otherwise program doesn't know.\n\
7679 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7680 Pass and Stop may be combined.\n\
7682 Multiple signals may be specified. Signal numbers and signal names\n\
7683 may be interspersed with actions, with the actions being performed for\n\
7684 all signals cumulatively specified."));
7685 set_cmd_completer (c
, handle_completer
);
7688 stop_command
= add_cmd ("stop", class_obscure
,
7689 not_just_help_class_command
, _("\
7690 There is no `stop' command, but you can set a hook on `stop'.\n\
7691 This allows you to set a list of commands to be run each time execution\n\
7692 of the program stops."), &cmdlist
);
7694 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7695 Set inferior debugging."), _("\
7696 Show inferior debugging."), _("\
7697 When non-zero, inferior specific debugging is enabled."),
7700 &setdebuglist
, &showdebuglist
);
7702 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7703 &debug_displaced
, _("\
7704 Set displaced stepping debugging."), _("\
7705 Show displaced stepping debugging."), _("\
7706 When non-zero, displaced stepping specific debugging is enabled."),
7708 show_debug_displaced
,
7709 &setdebuglist
, &showdebuglist
);
7711 add_setshow_boolean_cmd ("non-stop", no_class
,
7713 Set whether gdb controls the inferior in non-stop mode."), _("\
7714 Show whether gdb controls the inferior in non-stop mode."), _("\
7715 When debugging a multi-threaded program and this setting is\n\
7716 off (the default, also called all-stop mode), when one thread stops\n\
7717 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7718 all other threads in the program while you interact with the thread of\n\
7719 interest. When you continue or step a thread, you can allow the other\n\
7720 threads to run, or have them remain stopped, but while you inspect any\n\
7721 thread's state, all threads stop.\n\
7723 In non-stop mode, when one thread stops, other threads can continue\n\
7724 to run freely. You'll be able to step each thread independently,\n\
7725 leave it stopped or free to run as needed."),
7731 numsigs
= (int) GDB_SIGNAL_LAST
;
7732 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7733 signal_print
= (unsigned char *)
7734 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7735 signal_program
= (unsigned char *)
7736 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7737 signal_catch
= (unsigned char *)
7738 xmalloc (sizeof (signal_catch
[0]) * numsigs
);
7739 signal_pass
= (unsigned char *)
7740 xmalloc (sizeof (signal_pass
[0]) * numsigs
);
7741 for (i
= 0; i
< numsigs
; i
++)
7744 signal_print
[i
] = 1;
7745 signal_program
[i
] = 1;
7746 signal_catch
[i
] = 0;
7749 /* Signals caused by debugger's own actions
7750 should not be given to the program afterwards. */
7751 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7752 signal_program
[GDB_SIGNAL_INT
] = 0;
7754 /* Signals that are not errors should not normally enter the debugger. */
7755 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7756 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7757 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7758 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7759 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7760 signal_print
[GDB_SIGNAL_PROF
] = 0;
7761 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7762 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7763 signal_stop
[GDB_SIGNAL_IO
] = 0;
7764 signal_print
[GDB_SIGNAL_IO
] = 0;
7765 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7766 signal_print
[GDB_SIGNAL_POLL
] = 0;
7767 signal_stop
[GDB_SIGNAL_URG
] = 0;
7768 signal_print
[GDB_SIGNAL_URG
] = 0;
7769 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7770 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7771 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7772 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7774 /* These signals are used internally by user-level thread
7775 implementations. (See signal(5) on Solaris.) Like the above
7776 signals, a healthy program receives and handles them as part of
7777 its normal operation. */
7778 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7779 signal_print
[GDB_SIGNAL_LWP
] = 0;
7780 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7781 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7782 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7783 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7785 /* Update cached state. */
7786 signal_cache_update (-1);
7788 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7789 &stop_on_solib_events
, _("\
7790 Set stopping for shared library events."), _("\
7791 Show stopping for shared library events."), _("\
7792 If nonzero, gdb will give control to the user when the dynamic linker\n\
7793 notifies gdb of shared library events. The most common event of interest\n\
7794 to the user would be loading/unloading of a new library."),
7795 set_stop_on_solib_events
,
7796 show_stop_on_solib_events
,
7797 &setlist
, &showlist
);
7799 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7800 follow_fork_mode_kind_names
,
7801 &follow_fork_mode_string
, _("\
7802 Set debugger response to a program call of fork or vfork."), _("\
7803 Show debugger response to a program call of fork or vfork."), _("\
7804 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7805 parent - the original process is debugged after a fork\n\
7806 child - the new process is debugged after a fork\n\
7807 The unfollowed process will continue to run.\n\
7808 By default, the debugger will follow the parent process."),
7810 show_follow_fork_mode_string
,
7811 &setlist
, &showlist
);
7813 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7814 follow_exec_mode_names
,
7815 &follow_exec_mode_string
, _("\
7816 Set debugger response to a program call of exec."), _("\
7817 Show debugger response to a program call of exec."), _("\
7818 An exec call replaces the program image of a process.\n\
7820 follow-exec-mode can be:\n\
7822 new - the debugger creates a new inferior and rebinds the process\n\
7823 to this new inferior. The program the process was running before\n\
7824 the exec call can be restarted afterwards by restarting the original\n\
7827 same - the debugger keeps the process bound to the same inferior.\n\
7828 The new executable image replaces the previous executable loaded in\n\
7829 the inferior. Restarting the inferior after the exec call restarts\n\
7830 the executable the process was running after the exec call.\n\
7832 By default, the debugger will use the same inferior."),
7834 show_follow_exec_mode_string
,
7835 &setlist
, &showlist
);
7837 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7838 scheduler_enums
, &scheduler_mode
, _("\
7839 Set mode for locking scheduler during execution."), _("\
7840 Show mode for locking scheduler during execution."), _("\
7841 off == no locking (threads may preempt at any time)\n\
7842 on == full locking (no thread except the current thread may run)\n\
7843 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
7844 In this mode, other threads may run during other commands."),
7845 set_schedlock_func
, /* traps on target vector */
7846 show_scheduler_mode
,
7847 &setlist
, &showlist
);
7849 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7850 Set mode for resuming threads of all processes."), _("\
7851 Show mode for resuming threads of all processes."), _("\
7852 When on, execution commands (such as 'continue' or 'next') resume all\n\
7853 threads of all processes. When off (which is the default), execution\n\
7854 commands only resume the threads of the current process. The set of\n\
7855 threads that are resumed is further refined by the scheduler-locking\n\
7856 mode (see help set scheduler-locking)."),
7858 show_schedule_multiple
,
7859 &setlist
, &showlist
);
7861 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7862 Set mode of the step operation."), _("\
7863 Show mode of the step operation."), _("\
7864 When set, doing a step over a function without debug line information\n\
7865 will stop at the first instruction of that function. Otherwise, the\n\
7866 function is skipped and the step command stops at a different source line."),
7868 show_step_stop_if_no_debug
,
7869 &setlist
, &showlist
);
7871 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
7872 &can_use_displaced_stepping
, _("\
7873 Set debugger's willingness to use displaced stepping."), _("\
7874 Show debugger's willingness to use displaced stepping."), _("\
7875 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7876 supported by the target architecture. If off, gdb will not use displaced\n\
7877 stepping to step over breakpoints, even if such is supported by the target\n\
7878 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7879 if the target architecture supports it and non-stop mode is active, but will not\n\
7880 use it in all-stop mode (see help set non-stop)."),
7882 show_can_use_displaced_stepping
,
7883 &setlist
, &showlist
);
7885 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7886 &exec_direction
, _("Set direction of execution.\n\
7887 Options are 'forward' or 'reverse'."),
7888 _("Show direction of execution (forward/reverse)."),
7889 _("Tells gdb whether to execute forward or backward."),
7890 set_exec_direction_func
, show_exec_direction_func
,
7891 &setlist
, &showlist
);
7893 /* Set/show detach-on-fork: user-settable mode. */
7895 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7896 Set whether gdb will detach the child of a fork."), _("\
7897 Show whether gdb will detach the child of a fork."), _("\
7898 Tells gdb whether to detach the child of a fork."),
7899 NULL
, NULL
, &setlist
, &showlist
);
7901 /* Set/show disable address space randomization mode. */
7903 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7904 &disable_randomization
, _("\
7905 Set disabling of debuggee's virtual address space randomization."), _("\
7906 Show disabling of debuggee's virtual address space randomization."), _("\
7907 When this mode is on (which is the default), randomization of the virtual\n\
7908 address space is disabled. Standalone programs run with the randomization\n\
7909 enabled by default on some platforms."),
7910 &set_disable_randomization
,
7911 &show_disable_randomization
,
7912 &setlist
, &showlist
);
7914 /* ptid initializations */
7915 inferior_ptid
= null_ptid
;
7916 target_last_wait_ptid
= minus_one_ptid
;
7918 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7919 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7920 observer_attach_thread_exit (infrun_thread_thread_exit
);
7921 observer_attach_inferior_exit (infrun_inferior_exit
);
7923 /* Explicitly create without lookup, since that tries to create a
7924 value with a void typed value, and when we get here, gdbarch
7925 isn't initialized yet. At this point, we're quite sure there
7926 isn't another convenience variable of the same name. */
7927 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7929 add_setshow_boolean_cmd ("observer", no_class
,
7930 &observer_mode_1
, _("\
7931 Set whether gdb controls the inferior in observer mode."), _("\
7932 Show whether gdb controls the inferior in observer mode."), _("\
7933 In observer mode, GDB can get data from the inferior, but not\n\
7934 affect its execution. Registers and memory may not be changed,\n\
7935 breakpoints may not be set, and the program cannot be interrupted\n\