1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2017 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 #include "event-loop.h"
65 #include "thread-fsm.h"
66 #include "common/enum-flags.h"
68 /* Prototypes for local functions */
70 static void signals_info (char *, int);
72 static void handle_command (char *, int);
74 static void sig_print_info (enum gdb_signal
);
76 static void sig_print_header (void);
78 static void resume_cleanups (void *);
80 static int hook_stop_stub (void *);
82 static int restore_selected_frame (void *);
84 static int follow_fork (void);
86 static int follow_fork_inferior (int follow_child
, int detach_fork
);
88 static void follow_inferior_reset_breakpoints (void);
90 static void set_schedlock_func (char *args
, int from_tty
,
91 struct cmd_list_element
*c
);
93 static int currently_stepping (struct thread_info
*tp
);
95 void _initialize_infrun (void);
97 void nullify_last_target_wait_ptid (void);
99 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
101 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
103 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
105 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
107 /* Asynchronous signal handler registered as event loop source for
108 when we have pending events ready to be passed to the core. */
109 static struct async_event_handler
*infrun_async_inferior_event_token
;
111 /* Stores whether infrun_async was previously enabled or disabled.
112 Starts off as -1, indicating "never enabled/disabled". */
113 static int infrun_is_async
= -1;
118 infrun_async (int enable
)
120 if (infrun_is_async
!= enable
)
122 infrun_is_async
= enable
;
125 fprintf_unfiltered (gdb_stdlog
,
126 "infrun: infrun_async(%d)\n",
130 mark_async_event_handler (infrun_async_inferior_event_token
);
132 clear_async_event_handler (infrun_async_inferior_event_token
);
139 mark_infrun_async_event_handler (void)
141 mark_async_event_handler (infrun_async_inferior_event_token
);
144 /* When set, stop the 'step' command if we enter a function which has
145 no line number information. The normal behavior is that we step
146 over such function. */
147 int step_stop_if_no_debug
= 0;
149 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
150 struct cmd_list_element
*c
, const char *value
)
152 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
155 /* proceed and normal_stop use this to notify the user when the
156 inferior stopped in a different thread than it had been running
159 static ptid_t previous_inferior_ptid
;
161 /* If set (default for legacy reasons), when following a fork, GDB
162 will detach from one of the fork branches, child or parent.
163 Exactly which branch is detached depends on 'set follow-fork-mode'
166 static int detach_fork
= 1;
168 int debug_displaced
= 0;
170 show_debug_displaced (struct ui_file
*file
, int from_tty
,
171 struct cmd_list_element
*c
, const char *value
)
173 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
176 unsigned int debug_infrun
= 0;
178 show_debug_infrun (struct ui_file
*file
, int from_tty
,
179 struct cmd_list_element
*c
, const char *value
)
181 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
185 /* Support for disabling address space randomization. */
187 int disable_randomization
= 1;
190 show_disable_randomization (struct ui_file
*file
, int from_tty
,
191 struct cmd_list_element
*c
, const char *value
)
193 if (target_supports_disable_randomization ())
194 fprintf_filtered (file
,
195 _("Disabling randomization of debuggee's "
196 "virtual address space is %s.\n"),
199 fputs_filtered (_("Disabling randomization of debuggee's "
200 "virtual address space is unsupported on\n"
201 "this platform.\n"), file
);
205 set_disable_randomization (char *args
, int from_tty
,
206 struct cmd_list_element
*c
)
208 if (!target_supports_disable_randomization ())
209 error (_("Disabling randomization of debuggee's "
210 "virtual address space is unsupported on\n"
214 /* User interface for non-stop mode. */
217 static int non_stop_1
= 0;
220 set_non_stop (char *args
, int from_tty
,
221 struct cmd_list_element
*c
)
223 if (target_has_execution
)
225 non_stop_1
= non_stop
;
226 error (_("Cannot change this setting while the inferior is running."));
229 non_stop
= non_stop_1
;
233 show_non_stop (struct ui_file
*file
, int from_tty
,
234 struct cmd_list_element
*c
, const char *value
)
236 fprintf_filtered (file
,
237 _("Controlling the inferior in non-stop mode is %s.\n"),
241 /* "Observer mode" is somewhat like a more extreme version of
242 non-stop, in which all GDB operations that might affect the
243 target's execution have been disabled. */
245 int observer_mode
= 0;
246 static int observer_mode_1
= 0;
249 set_observer_mode (char *args
, int from_tty
,
250 struct cmd_list_element
*c
)
252 if (target_has_execution
)
254 observer_mode_1
= observer_mode
;
255 error (_("Cannot change this setting while the inferior is running."));
258 observer_mode
= observer_mode_1
;
260 may_write_registers
= !observer_mode
;
261 may_write_memory
= !observer_mode
;
262 may_insert_breakpoints
= !observer_mode
;
263 may_insert_tracepoints
= !observer_mode
;
264 /* We can insert fast tracepoints in or out of observer mode,
265 but enable them if we're going into this mode. */
267 may_insert_fast_tracepoints
= 1;
268 may_stop
= !observer_mode
;
269 update_target_permissions ();
271 /* Going *into* observer mode we must force non-stop, then
272 going out we leave it that way. */
275 pagination_enabled
= 0;
276 non_stop
= non_stop_1
= 1;
280 printf_filtered (_("Observer mode is now %s.\n"),
281 (observer_mode
? "on" : "off"));
285 show_observer_mode (struct ui_file
*file
, int from_tty
,
286 struct cmd_list_element
*c
, const char *value
)
288 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
291 /* This updates the value of observer mode based on changes in
292 permissions. Note that we are deliberately ignoring the values of
293 may-write-registers and may-write-memory, since the user may have
294 reason to enable these during a session, for instance to turn on a
295 debugging-related global. */
298 update_observer_mode (void)
302 newval
= (!may_insert_breakpoints
303 && !may_insert_tracepoints
304 && may_insert_fast_tracepoints
308 /* Let the user know if things change. */
309 if (newval
!= observer_mode
)
310 printf_filtered (_("Observer mode is now %s.\n"),
311 (newval
? "on" : "off"));
313 observer_mode
= observer_mode_1
= newval
;
316 /* Tables of how to react to signals; the user sets them. */
318 static unsigned char *signal_stop
;
319 static unsigned char *signal_print
;
320 static unsigned char *signal_program
;
322 /* Table of signals that are registered with "catch signal". A
323 non-zero entry indicates that the signal is caught by some "catch
324 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
326 static unsigned char *signal_catch
;
328 /* Table of signals that the target may silently handle.
329 This is automatically determined from the flags above,
330 and simply cached here. */
331 static unsigned char *signal_pass
;
333 #define SET_SIGS(nsigs,sigs,flags) \
335 int signum = (nsigs); \
336 while (signum-- > 0) \
337 if ((sigs)[signum]) \
338 (flags)[signum] = 1; \
341 #define UNSET_SIGS(nsigs,sigs,flags) \
343 int signum = (nsigs); \
344 while (signum-- > 0) \
345 if ((sigs)[signum]) \
346 (flags)[signum] = 0; \
349 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
350 this function is to avoid exporting `signal_program'. */
353 update_signals_program_target (void)
355 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
358 /* Value to pass to target_resume() to cause all threads to resume. */
360 #define RESUME_ALL minus_one_ptid
362 /* Command list pointer for the "stop" placeholder. */
364 static struct cmd_list_element
*stop_command
;
366 /* Nonzero if we want to give control to the user when we're notified
367 of shared library events by the dynamic linker. */
368 int stop_on_solib_events
;
370 /* Enable or disable optional shared library event breakpoints
371 as appropriate when the above flag is changed. */
374 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
376 update_solib_breakpoints ();
380 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
381 struct cmd_list_element
*c
, const char *value
)
383 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
387 /* Nonzero after stop if current stack frame should be printed. */
389 static int stop_print_frame
;
391 /* This is a cached copy of the pid/waitstatus of the last event
392 returned by target_wait()/deprecated_target_wait_hook(). This
393 information is returned by get_last_target_status(). */
394 static ptid_t target_last_wait_ptid
;
395 static struct target_waitstatus target_last_waitstatus
;
397 static void context_switch (ptid_t ptid
);
399 void init_thread_stepping_state (struct thread_info
*tss
);
401 static const char follow_fork_mode_child
[] = "child";
402 static const char follow_fork_mode_parent
[] = "parent";
404 static const char *const follow_fork_mode_kind_names
[] = {
405 follow_fork_mode_child
,
406 follow_fork_mode_parent
,
410 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
412 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
413 struct cmd_list_element
*c
, const char *value
)
415 fprintf_filtered (file
,
416 _("Debugger response to a program "
417 "call of fork or vfork is \"%s\".\n"),
422 /* Handle changes to the inferior list based on the type of fork,
423 which process is being followed, and whether the other process
424 should be detached. On entry inferior_ptid must be the ptid of
425 the fork parent. At return inferior_ptid is the ptid of the
426 followed inferior. */
429 follow_fork_inferior (int follow_child
, int detach_fork
)
432 ptid_t parent_ptid
, child_ptid
;
434 has_vforked
= (inferior_thread ()->pending_follow
.kind
435 == TARGET_WAITKIND_VFORKED
);
436 parent_ptid
= inferior_ptid
;
437 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
440 && !non_stop
/* Non-stop always resumes both branches. */
441 && current_ui
->prompt_state
== PROMPT_BLOCKED
442 && !(follow_child
|| detach_fork
|| sched_multi
))
444 /* The parent stays blocked inside the vfork syscall until the
445 child execs or exits. If we don't let the child run, then
446 the parent stays blocked. If we're telling the parent to run
447 in the foreground, the user will not be able to ctrl-c to get
448 back the terminal, effectively hanging the debug session. */
449 fprintf_filtered (gdb_stderr
, _("\
450 Can not resume the parent process over vfork in the foreground while\n\
451 holding the child stopped. Try \"set detach-on-fork\" or \
452 \"set schedule-multiple\".\n"));
453 /* FIXME output string > 80 columns. */
459 /* Detach new forked process? */
462 /* Before detaching from the child, remove all breakpoints
463 from it. If we forked, then this has already been taken
464 care of by infrun.c. If we vforked however, any
465 breakpoint inserted in the parent is visible in the
466 child, even those added while stopped in a vfork
467 catchpoint. This will remove the breakpoints from the
468 parent also, but they'll be reinserted below. */
471 /* Keep breakpoints list in sync. */
472 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
475 if (info_verbose
|| debug_infrun
)
477 /* Ensure that we have a process ptid. */
478 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
480 target_terminal_ours_for_output ();
481 fprintf_filtered (gdb_stdlog
,
482 _("Detaching after %s from child %s.\n"),
483 has_vforked
? "vfork" : "fork",
484 target_pid_to_str (process_ptid
));
489 struct inferior
*parent_inf
, *child_inf
;
490 struct cleanup
*old_chain
;
492 /* Add process to GDB's tables. */
493 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
495 parent_inf
= current_inferior ();
496 child_inf
->attach_flag
= parent_inf
->attach_flag
;
497 copy_terminal_info (child_inf
, parent_inf
);
498 child_inf
->gdbarch
= parent_inf
->gdbarch
;
499 copy_inferior_target_desc_info (child_inf
, parent_inf
);
501 old_chain
= save_inferior_ptid ();
502 save_current_program_space ();
504 inferior_ptid
= child_ptid
;
505 add_thread (inferior_ptid
);
506 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
508 /* If this is a vfork child, then the address-space is
509 shared with the parent. */
512 child_inf
->pspace
= parent_inf
->pspace
;
513 child_inf
->aspace
= parent_inf
->aspace
;
515 /* The parent will be frozen until the child is done
516 with the shared region. Keep track of the
518 child_inf
->vfork_parent
= parent_inf
;
519 child_inf
->pending_detach
= 0;
520 parent_inf
->vfork_child
= child_inf
;
521 parent_inf
->pending_detach
= 0;
525 child_inf
->aspace
= new_address_space ();
526 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
527 child_inf
->removable
= 1;
528 set_current_program_space (child_inf
->pspace
);
529 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
531 /* Let the shared library layer (e.g., solib-svr4) learn
532 about this new process, relocate the cloned exec, pull
533 in shared libraries, and install the solib event
534 breakpoint. If a "cloned-VM" event was propagated
535 better throughout the core, this wouldn't be
537 solib_create_inferior_hook (0);
540 do_cleanups (old_chain
);
545 struct inferior
*parent_inf
;
547 parent_inf
= current_inferior ();
549 /* If we detached from the child, then we have to be careful
550 to not insert breakpoints in the parent until the child
551 is done with the shared memory region. However, if we're
552 staying attached to the child, then we can and should
553 insert breakpoints, so that we can debug it. A
554 subsequent child exec or exit is enough to know when does
555 the child stops using the parent's address space. */
556 parent_inf
->waiting_for_vfork_done
= detach_fork
;
557 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
562 /* Follow the child. */
563 struct inferior
*parent_inf
, *child_inf
;
564 struct program_space
*parent_pspace
;
566 if (info_verbose
|| debug_infrun
)
568 target_terminal_ours_for_output ();
569 fprintf_filtered (gdb_stdlog
,
570 _("Attaching after %s %s to child %s.\n"),
571 target_pid_to_str (parent_ptid
),
572 has_vforked
? "vfork" : "fork",
573 target_pid_to_str (child_ptid
));
576 /* Add the new inferior first, so that the target_detach below
577 doesn't unpush the target. */
579 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
581 parent_inf
= current_inferior ();
582 child_inf
->attach_flag
= parent_inf
->attach_flag
;
583 copy_terminal_info (child_inf
, parent_inf
);
584 child_inf
->gdbarch
= parent_inf
->gdbarch
;
585 copy_inferior_target_desc_info (child_inf
, parent_inf
);
587 parent_pspace
= parent_inf
->pspace
;
589 /* If we're vforking, we want to hold on to the parent until the
590 child exits or execs. At child exec or exit time we can
591 remove the old breakpoints from the parent and detach or
592 resume debugging it. Otherwise, detach the parent now; we'll
593 want to reuse it's program/address spaces, but we can't set
594 them to the child before removing breakpoints from the
595 parent, otherwise, the breakpoints module could decide to
596 remove breakpoints from the wrong process (since they'd be
597 assigned to the same address space). */
601 gdb_assert (child_inf
->vfork_parent
== NULL
);
602 gdb_assert (parent_inf
->vfork_child
== NULL
);
603 child_inf
->vfork_parent
= parent_inf
;
604 child_inf
->pending_detach
= 0;
605 parent_inf
->vfork_child
= child_inf
;
606 parent_inf
->pending_detach
= detach_fork
;
607 parent_inf
->waiting_for_vfork_done
= 0;
609 else if (detach_fork
)
611 if (info_verbose
|| debug_infrun
)
613 /* Ensure that we have a process ptid. */
614 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
616 target_terminal_ours_for_output ();
617 fprintf_filtered (gdb_stdlog
,
618 _("Detaching after fork from "
620 target_pid_to_str (process_ptid
));
623 target_detach (NULL
, 0);
626 /* Note that the detach above makes PARENT_INF dangling. */
628 /* Add the child thread to the appropriate lists, and switch to
629 this new thread, before cloning the program space, and
630 informing the solib layer about this new process. */
632 inferior_ptid
= child_ptid
;
633 add_thread (inferior_ptid
);
635 /* If this is a vfork child, then the address-space is shared
636 with the parent. If we detached from the parent, then we can
637 reuse the parent's program/address spaces. */
638 if (has_vforked
|| detach_fork
)
640 child_inf
->pspace
= parent_pspace
;
641 child_inf
->aspace
= child_inf
->pspace
->aspace
;
645 child_inf
->aspace
= new_address_space ();
646 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
647 child_inf
->removable
= 1;
648 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
649 set_current_program_space (child_inf
->pspace
);
650 clone_program_space (child_inf
->pspace
, parent_pspace
);
652 /* Let the shared library layer (e.g., solib-svr4) learn
653 about this new process, relocate the cloned exec, pull in
654 shared libraries, and install the solib event breakpoint.
655 If a "cloned-VM" event was propagated better throughout
656 the core, this wouldn't be required. */
657 solib_create_inferior_hook (0);
661 return target_follow_fork (follow_child
, detach_fork
);
664 /* Tell the target to follow the fork we're stopped at. Returns true
665 if the inferior should be resumed; false, if the target for some
666 reason decided it's best not to resume. */
671 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
672 int should_resume
= 1;
673 struct thread_info
*tp
;
675 /* Copy user stepping state to the new inferior thread. FIXME: the
676 followed fork child thread should have a copy of most of the
677 parent thread structure's run control related fields, not just these.
678 Initialized to avoid "may be used uninitialized" warnings from gcc. */
679 struct breakpoint
*step_resume_breakpoint
= NULL
;
680 struct breakpoint
*exception_resume_breakpoint
= NULL
;
681 CORE_ADDR step_range_start
= 0;
682 CORE_ADDR step_range_end
= 0;
683 struct frame_id step_frame_id
= { 0 };
684 struct thread_fsm
*thread_fsm
= NULL
;
689 struct target_waitstatus wait_status
;
691 /* Get the last target status returned by target_wait(). */
692 get_last_target_status (&wait_ptid
, &wait_status
);
694 /* If not stopped at a fork event, then there's nothing else to
696 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
697 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
700 /* Check if we switched over from WAIT_PTID, since the event was
702 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
703 && !ptid_equal (inferior_ptid
, wait_ptid
))
705 /* We did. Switch back to WAIT_PTID thread, to tell the
706 target to follow it (in either direction). We'll
707 afterwards refuse to resume, and inform the user what
709 switch_to_thread (wait_ptid
);
714 tp
= inferior_thread ();
716 /* If there were any forks/vforks that were caught and are now to be
717 followed, then do so now. */
718 switch (tp
->pending_follow
.kind
)
720 case TARGET_WAITKIND_FORKED
:
721 case TARGET_WAITKIND_VFORKED
:
723 ptid_t parent
, child
;
725 /* If the user did a next/step, etc, over a fork call,
726 preserve the stepping state in the fork child. */
727 if (follow_child
&& should_resume
)
729 step_resume_breakpoint
= clone_momentary_breakpoint
730 (tp
->control
.step_resume_breakpoint
);
731 step_range_start
= tp
->control
.step_range_start
;
732 step_range_end
= tp
->control
.step_range_end
;
733 step_frame_id
= tp
->control
.step_frame_id
;
734 exception_resume_breakpoint
735 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
736 thread_fsm
= tp
->thread_fsm
;
738 /* For now, delete the parent's sr breakpoint, otherwise,
739 parent/child sr breakpoints are considered duplicates,
740 and the child version will not be installed. Remove
741 this when the breakpoints module becomes aware of
742 inferiors and address spaces. */
743 delete_step_resume_breakpoint (tp
);
744 tp
->control
.step_range_start
= 0;
745 tp
->control
.step_range_end
= 0;
746 tp
->control
.step_frame_id
= null_frame_id
;
747 delete_exception_resume_breakpoint (tp
);
748 tp
->thread_fsm
= NULL
;
751 parent
= inferior_ptid
;
752 child
= tp
->pending_follow
.value
.related_pid
;
754 /* Set up inferior(s) as specified by the caller, and tell the
755 target to do whatever is necessary to follow either parent
757 if (follow_fork_inferior (follow_child
, detach_fork
))
759 /* Target refused to follow, or there's some other reason
760 we shouldn't resume. */
765 /* This pending follow fork event is now handled, one way
766 or another. The previous selected thread may be gone
767 from the lists by now, but if it is still around, need
768 to clear the pending follow request. */
769 tp
= find_thread_ptid (parent
);
771 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
773 /* This makes sure we don't try to apply the "Switched
774 over from WAIT_PID" logic above. */
775 nullify_last_target_wait_ptid ();
777 /* If we followed the child, switch to it... */
780 switch_to_thread (child
);
782 /* ... and preserve the stepping state, in case the
783 user was stepping over the fork call. */
786 tp
= inferior_thread ();
787 tp
->control
.step_resume_breakpoint
788 = step_resume_breakpoint
;
789 tp
->control
.step_range_start
= step_range_start
;
790 tp
->control
.step_range_end
= step_range_end
;
791 tp
->control
.step_frame_id
= step_frame_id
;
792 tp
->control
.exception_resume_breakpoint
793 = exception_resume_breakpoint
;
794 tp
->thread_fsm
= thread_fsm
;
798 /* If we get here, it was because we're trying to
799 resume from a fork catchpoint, but, the user
800 has switched threads away from the thread that
801 forked. In that case, the resume command
802 issued is most likely not applicable to the
803 child, so just warn, and refuse to resume. */
804 warning (_("Not resuming: switched threads "
805 "before following fork child."));
808 /* Reset breakpoints in the child as appropriate. */
809 follow_inferior_reset_breakpoints ();
812 switch_to_thread (parent
);
816 case TARGET_WAITKIND_SPURIOUS
:
817 /* Nothing to follow. */
820 internal_error (__FILE__
, __LINE__
,
821 "Unexpected pending_follow.kind %d\n",
822 tp
->pending_follow
.kind
);
826 return should_resume
;
830 follow_inferior_reset_breakpoints (void)
832 struct thread_info
*tp
= inferior_thread ();
834 /* Was there a step_resume breakpoint? (There was if the user
835 did a "next" at the fork() call.) If so, explicitly reset its
836 thread number. Cloned step_resume breakpoints are disabled on
837 creation, so enable it here now that it is associated with the
840 step_resumes are a form of bp that are made to be per-thread.
841 Since we created the step_resume bp when the parent process
842 was being debugged, and now are switching to the child process,
843 from the breakpoint package's viewpoint, that's a switch of
844 "threads". We must update the bp's notion of which thread
845 it is for, or it'll be ignored when it triggers. */
847 if (tp
->control
.step_resume_breakpoint
)
849 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
850 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
853 /* Treat exception_resume breakpoints like step_resume breakpoints. */
854 if (tp
->control
.exception_resume_breakpoint
)
856 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
857 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
860 /* Reinsert all breakpoints in the child. The user may have set
861 breakpoints after catching the fork, in which case those
862 were never set in the child, but only in the parent. This makes
863 sure the inserted breakpoints match the breakpoint list. */
865 breakpoint_re_set ();
866 insert_breakpoints ();
869 /* The child has exited or execed: resume threads of the parent the
870 user wanted to be executing. */
873 proceed_after_vfork_done (struct thread_info
*thread
,
876 int pid
= * (int *) arg
;
878 if (ptid_get_pid (thread
->ptid
) == pid
879 && is_running (thread
->ptid
)
880 && !is_executing (thread
->ptid
)
881 && !thread
->stop_requested
882 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
885 fprintf_unfiltered (gdb_stdlog
,
886 "infrun: resuming vfork parent thread %s\n",
887 target_pid_to_str (thread
->ptid
));
889 switch_to_thread (thread
->ptid
);
890 clear_proceed_status (0);
891 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
897 /* Called whenever we notice an exec or exit event, to handle
898 detaching or resuming a vfork parent. */
901 handle_vfork_child_exec_or_exit (int exec
)
903 struct inferior
*inf
= current_inferior ();
905 if (inf
->vfork_parent
)
907 int resume_parent
= -1;
909 /* This exec or exit marks the end of the shared memory region
910 between the parent and the child. If the user wanted to
911 detach from the parent, now is the time. */
913 if (inf
->vfork_parent
->pending_detach
)
915 struct thread_info
*tp
;
916 struct cleanup
*old_chain
;
917 struct program_space
*pspace
;
918 struct address_space
*aspace
;
920 /* follow-fork child, detach-on-fork on. */
922 inf
->vfork_parent
->pending_detach
= 0;
926 /* If we're handling a child exit, then inferior_ptid
927 points at the inferior's pid, not to a thread. */
928 old_chain
= save_inferior_ptid ();
929 save_current_program_space ();
930 save_current_inferior ();
933 old_chain
= save_current_space_and_thread ();
935 /* We're letting loose of the parent. */
936 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
937 switch_to_thread (tp
->ptid
);
939 /* We're about to detach from the parent, which implicitly
940 removes breakpoints from its address space. There's a
941 catch here: we want to reuse the spaces for the child,
942 but, parent/child are still sharing the pspace at this
943 point, although the exec in reality makes the kernel give
944 the child a fresh set of new pages. The problem here is
945 that the breakpoints module being unaware of this, would
946 likely chose the child process to write to the parent
947 address space. Swapping the child temporarily away from
948 the spaces has the desired effect. Yes, this is "sort
951 pspace
= inf
->pspace
;
952 aspace
= inf
->aspace
;
956 if (debug_infrun
|| info_verbose
)
958 target_terminal_ours_for_output ();
962 fprintf_filtered (gdb_stdlog
,
963 _("Detaching vfork parent process "
964 "%d after child exec.\n"),
965 inf
->vfork_parent
->pid
);
969 fprintf_filtered (gdb_stdlog
,
970 _("Detaching vfork parent process "
971 "%d after child exit.\n"),
972 inf
->vfork_parent
->pid
);
976 target_detach (NULL
, 0);
979 inf
->pspace
= pspace
;
980 inf
->aspace
= aspace
;
982 do_cleanups (old_chain
);
986 /* We're staying attached to the parent, so, really give the
987 child a new address space. */
988 inf
->pspace
= add_program_space (maybe_new_address_space ());
989 inf
->aspace
= inf
->pspace
->aspace
;
991 set_current_program_space (inf
->pspace
);
993 resume_parent
= inf
->vfork_parent
->pid
;
995 /* Break the bonds. */
996 inf
->vfork_parent
->vfork_child
= NULL
;
1000 struct cleanup
*old_chain
;
1001 struct program_space
*pspace
;
1003 /* If this is a vfork child exiting, then the pspace and
1004 aspaces were shared with the parent. Since we're
1005 reporting the process exit, we'll be mourning all that is
1006 found in the address space, and switching to null_ptid,
1007 preparing to start a new inferior. But, since we don't
1008 want to clobber the parent's address/program spaces, we
1009 go ahead and create a new one for this exiting
1012 /* Switch to null_ptid, so that clone_program_space doesn't want
1013 to read the selected frame of a dead process. */
1014 old_chain
= save_inferior_ptid ();
1015 inferior_ptid
= null_ptid
;
1017 /* This inferior is dead, so avoid giving the breakpoints
1018 module the option to write through to it (cloning a
1019 program space resets breakpoints). */
1022 pspace
= add_program_space (maybe_new_address_space ());
1023 set_current_program_space (pspace
);
1025 inf
->symfile_flags
= SYMFILE_NO_READ
;
1026 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1027 inf
->pspace
= pspace
;
1028 inf
->aspace
= pspace
->aspace
;
1030 /* Put back inferior_ptid. We'll continue mourning this
1032 do_cleanups (old_chain
);
1034 resume_parent
= inf
->vfork_parent
->pid
;
1035 /* Break the bonds. */
1036 inf
->vfork_parent
->vfork_child
= NULL
;
1039 inf
->vfork_parent
= NULL
;
1041 gdb_assert (current_program_space
== inf
->pspace
);
1043 if (non_stop
&& resume_parent
!= -1)
1045 /* If the user wanted the parent to be running, let it go
1047 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1050 fprintf_unfiltered (gdb_stdlog
,
1051 "infrun: resuming vfork parent process %d\n",
1054 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1056 do_cleanups (old_chain
);
1061 /* Enum strings for "set|show follow-exec-mode". */
1063 static const char follow_exec_mode_new
[] = "new";
1064 static const char follow_exec_mode_same
[] = "same";
1065 static const char *const follow_exec_mode_names
[] =
1067 follow_exec_mode_new
,
1068 follow_exec_mode_same
,
1072 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1074 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1075 struct cmd_list_element
*c
, const char *value
)
1077 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1080 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1083 follow_exec (ptid_t ptid
, char *exec_file_target
)
1085 struct thread_info
*th
, *tmp
;
1086 struct inferior
*inf
= current_inferior ();
1087 int pid
= ptid_get_pid (ptid
);
1088 ptid_t process_ptid
;
1089 char *exec_file_host
;
1090 struct cleanup
*old_chain
;
1092 /* This is an exec event that we actually wish to pay attention to.
1093 Refresh our symbol table to the newly exec'd program, remove any
1094 momentary bp's, etc.
1096 If there are breakpoints, they aren't really inserted now,
1097 since the exec() transformed our inferior into a fresh set
1100 We want to preserve symbolic breakpoints on the list, since
1101 we have hopes that they can be reset after the new a.out's
1102 symbol table is read.
1104 However, any "raw" breakpoints must be removed from the list
1105 (e.g., the solib bp's), since their address is probably invalid
1108 And, we DON'T want to call delete_breakpoints() here, since
1109 that may write the bp's "shadow contents" (the instruction
1110 value that was overwritten witha TRAP instruction). Since
1111 we now have a new a.out, those shadow contents aren't valid. */
1113 mark_breakpoints_out ();
1115 /* The target reports the exec event to the main thread, even if
1116 some other thread does the exec, and even if the main thread was
1117 stopped or already gone. We may still have non-leader threads of
1118 the process on our list. E.g., on targets that don't have thread
1119 exit events (like remote); or on native Linux in non-stop mode if
1120 there were only two threads in the inferior and the non-leader
1121 one is the one that execs (and nothing forces an update of the
1122 thread list up to here). When debugging remotely, it's best to
1123 avoid extra traffic, when possible, so avoid syncing the thread
1124 list with the target, and instead go ahead and delete all threads
1125 of the process but one that reported the event. Note this must
1126 be done before calling update_breakpoints_after_exec, as
1127 otherwise clearing the threads' resources would reference stale
1128 thread breakpoints -- it may have been one of these threads that
1129 stepped across the exec. We could just clear their stepping
1130 states, but as long as we're iterating, might as well delete
1131 them. Deleting them now rather than at the next user-visible
1132 stop provides a nicer sequence of events for user and MI
1134 ALL_THREADS_SAFE (th
, tmp
)
1135 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1136 delete_thread (th
->ptid
);
1138 /* We also need to clear any left over stale state for the
1139 leader/event thread. E.g., if there was any step-resume
1140 breakpoint or similar, it's gone now. We cannot truly
1141 step-to-next statement through an exec(). */
1142 th
= inferior_thread ();
1143 th
->control
.step_resume_breakpoint
= NULL
;
1144 th
->control
.exception_resume_breakpoint
= NULL
;
1145 th
->control
.single_step_breakpoints
= NULL
;
1146 th
->control
.step_range_start
= 0;
1147 th
->control
.step_range_end
= 0;
1149 /* The user may have had the main thread held stopped in the
1150 previous image (e.g., schedlock on, or non-stop). Release
1152 th
->stop_requested
= 0;
1154 update_breakpoints_after_exec ();
1156 /* What is this a.out's name? */
1157 process_ptid
= pid_to_ptid (pid
);
1158 printf_unfiltered (_("%s is executing new program: %s\n"),
1159 target_pid_to_str (process_ptid
),
1162 /* We've followed the inferior through an exec. Therefore, the
1163 inferior has essentially been killed & reborn. */
1165 gdb_flush (gdb_stdout
);
1167 breakpoint_init_inferior (inf_execd
);
1169 exec_file_host
= exec_file_find (exec_file_target
, NULL
);
1170 old_chain
= make_cleanup (xfree
, exec_file_host
);
1172 /* If we were unable to map the executable target pathname onto a host
1173 pathname, tell the user that. Otherwise GDB's subsequent behavior
1174 is confusing. Maybe it would even be better to stop at this point
1175 so that the user can specify a file manually before continuing. */
1176 if (exec_file_host
== NULL
)
1177 warning (_("Could not load symbols for executable %s.\n"
1178 "Do you need \"set sysroot\"?"),
1181 /* Reset the shared library package. This ensures that we get a
1182 shlib event when the child reaches "_start", at which point the
1183 dld will have had a chance to initialize the child. */
1184 /* Also, loading a symbol file below may trigger symbol lookups, and
1185 we don't want those to be satisfied by the libraries of the
1186 previous incarnation of this process. */
1187 no_shared_libraries (NULL
, 0);
1189 if (follow_exec_mode_string
== follow_exec_mode_new
)
1191 /* The user wants to keep the old inferior and program spaces
1192 around. Create a new fresh one, and switch to it. */
1194 /* Do exit processing for the original inferior before adding
1195 the new inferior so we don't have two active inferiors with
1196 the same ptid, which can confuse find_inferior_ptid. */
1197 exit_inferior_num_silent (current_inferior ()->num
);
1199 inf
= add_inferior_with_spaces ();
1201 target_follow_exec (inf
, exec_file_target
);
1203 set_current_inferior (inf
);
1204 set_current_program_space (inf
->pspace
);
1209 /* The old description may no longer be fit for the new image.
1210 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1211 old description; we'll read a new one below. No need to do
1212 this on "follow-exec-mode new", as the old inferior stays
1213 around (its description is later cleared/refetched on
1215 target_clear_description ();
1218 gdb_assert (current_program_space
== inf
->pspace
);
1220 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1221 because the proper displacement for a PIE (Position Independent
1222 Executable) main symbol file will only be computed by
1223 solib_create_inferior_hook below. breakpoint_re_set would fail
1224 to insert the breakpoints with the zero displacement. */
1225 try_open_exec_file (exec_file_host
, inf
, SYMFILE_DEFER_BP_RESET
);
1227 do_cleanups (old_chain
);
1229 /* If the target can specify a description, read it. Must do this
1230 after flipping to the new executable (because the target supplied
1231 description must be compatible with the executable's
1232 architecture, and the old executable may e.g., be 32-bit, while
1233 the new one 64-bit), and before anything involving memory or
1235 target_find_description ();
1237 solib_create_inferior_hook (0);
1239 jit_inferior_created_hook ();
1241 breakpoint_re_set ();
1243 /* Reinsert all breakpoints. (Those which were symbolic have
1244 been reset to the proper address in the new a.out, thanks
1245 to symbol_file_command...). */
1246 insert_breakpoints ();
1248 /* The next resume of this inferior should bring it to the shlib
1249 startup breakpoints. (If the user had also set bp's on
1250 "main" from the old (parent) process, then they'll auto-
1251 matically get reset there in the new process.). */
1254 /* The queue of threads that need to do a step-over operation to get
1255 past e.g., a breakpoint. What technique is used to step over the
1256 breakpoint/watchpoint does not matter -- all threads end up in the
1257 same queue, to maintain rough temporal order of execution, in order
1258 to avoid starvation, otherwise, we could e.g., find ourselves
1259 constantly stepping the same couple threads past their breakpoints
1260 over and over, if the single-step finish fast enough. */
1261 struct thread_info
*step_over_queue_head
;
1263 /* Bit flags indicating what the thread needs to step over. */
1265 enum step_over_what_flag
1267 /* Step over a breakpoint. */
1268 STEP_OVER_BREAKPOINT
= 1,
1270 /* Step past a non-continuable watchpoint, in order to let the
1271 instruction execute so we can evaluate the watchpoint
1273 STEP_OVER_WATCHPOINT
= 2
1275 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1277 /* Info about an instruction that is being stepped over. */
1279 struct step_over_info
1281 /* If we're stepping past a breakpoint, this is the address space
1282 and address of the instruction the breakpoint is set at. We'll
1283 skip inserting all breakpoints here. Valid iff ASPACE is
1285 struct address_space
*aspace
;
1288 /* The instruction being stepped over triggers a nonsteppable
1289 watchpoint. If true, we'll skip inserting watchpoints. */
1290 int nonsteppable_watchpoint_p
;
1292 /* The thread's global number. */
1296 /* The step-over info of the location that is being stepped over.
1298 Note that with async/breakpoint always-inserted mode, a user might
1299 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1300 being stepped over. As setting a new breakpoint inserts all
1301 breakpoints, we need to make sure the breakpoint being stepped over
1302 isn't inserted then. We do that by only clearing the step-over
1303 info when the step-over is actually finished (or aborted).
1305 Presently GDB can only step over one breakpoint at any given time.
1306 Given threads that can't run code in the same address space as the
1307 breakpoint's can't really miss the breakpoint, GDB could be taught
1308 to step-over at most one breakpoint per address space (so this info
1309 could move to the address space object if/when GDB is extended).
1310 The set of breakpoints being stepped over will normally be much
1311 smaller than the set of all breakpoints, so a flag in the
1312 breakpoint location structure would be wasteful. A separate list
1313 also saves complexity and run-time, as otherwise we'd have to go
1314 through all breakpoint locations clearing their flag whenever we
1315 start a new sequence. Similar considerations weigh against storing
1316 this info in the thread object. Plus, not all step overs actually
1317 have breakpoint locations -- e.g., stepping past a single-step
1318 breakpoint, or stepping to complete a non-continuable
1320 static struct step_over_info step_over_info
;
1322 /* Record the address of the breakpoint/instruction we're currently
1324 N.B. We record the aspace and address now, instead of say just the thread,
1325 because when we need the info later the thread may be running. */
1328 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1329 int nonsteppable_watchpoint_p
,
1332 step_over_info
.aspace
= aspace
;
1333 step_over_info
.address
= address
;
1334 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1335 step_over_info
.thread
= thread
;
1338 /* Called when we're not longer stepping over a breakpoint / an
1339 instruction, so all breakpoints are free to be (re)inserted. */
1342 clear_step_over_info (void)
1345 fprintf_unfiltered (gdb_stdlog
,
1346 "infrun: clear_step_over_info\n");
1347 step_over_info
.aspace
= NULL
;
1348 step_over_info
.address
= 0;
1349 step_over_info
.nonsteppable_watchpoint_p
= 0;
1350 step_over_info
.thread
= -1;
1356 stepping_past_instruction_at (struct address_space
*aspace
,
1359 return (step_over_info
.aspace
!= NULL
1360 && breakpoint_address_match (aspace
, address
,
1361 step_over_info
.aspace
,
1362 step_over_info
.address
));
1368 thread_is_stepping_over_breakpoint (int thread
)
1370 return (step_over_info
.thread
!= -1
1371 && thread
== step_over_info
.thread
);
1377 stepping_past_nonsteppable_watchpoint (void)
1379 return step_over_info
.nonsteppable_watchpoint_p
;
1382 /* Returns true if step-over info is valid. */
1385 step_over_info_valid_p (void)
1387 return (step_over_info
.aspace
!= NULL
1388 || stepping_past_nonsteppable_watchpoint ());
1392 /* Displaced stepping. */
1394 /* In non-stop debugging mode, we must take special care to manage
1395 breakpoints properly; in particular, the traditional strategy for
1396 stepping a thread past a breakpoint it has hit is unsuitable.
1397 'Displaced stepping' is a tactic for stepping one thread past a
1398 breakpoint it has hit while ensuring that other threads running
1399 concurrently will hit the breakpoint as they should.
1401 The traditional way to step a thread T off a breakpoint in a
1402 multi-threaded program in all-stop mode is as follows:
1404 a0) Initially, all threads are stopped, and breakpoints are not
1406 a1) We single-step T, leaving breakpoints uninserted.
1407 a2) We insert breakpoints, and resume all threads.
1409 In non-stop debugging, however, this strategy is unsuitable: we
1410 don't want to have to stop all threads in the system in order to
1411 continue or step T past a breakpoint. Instead, we use displaced
1414 n0) Initially, T is stopped, other threads are running, and
1415 breakpoints are inserted.
1416 n1) We copy the instruction "under" the breakpoint to a separate
1417 location, outside the main code stream, making any adjustments
1418 to the instruction, register, and memory state as directed by
1420 n2) We single-step T over the instruction at its new location.
1421 n3) We adjust the resulting register and memory state as directed
1422 by T's architecture. This includes resetting T's PC to point
1423 back into the main instruction stream.
1426 This approach depends on the following gdbarch methods:
1428 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1429 indicate where to copy the instruction, and how much space must
1430 be reserved there. We use these in step n1.
1432 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1433 address, and makes any necessary adjustments to the instruction,
1434 register contents, and memory. We use this in step n1.
1436 - gdbarch_displaced_step_fixup adjusts registers and memory after
1437 we have successfuly single-stepped the instruction, to yield the
1438 same effect the instruction would have had if we had executed it
1439 at its original address. We use this in step n3.
1441 - gdbarch_displaced_step_free_closure provides cleanup.
1443 The gdbarch_displaced_step_copy_insn and
1444 gdbarch_displaced_step_fixup functions must be written so that
1445 copying an instruction with gdbarch_displaced_step_copy_insn,
1446 single-stepping across the copied instruction, and then applying
1447 gdbarch_displaced_insn_fixup should have the same effects on the
1448 thread's memory and registers as stepping the instruction in place
1449 would have. Exactly which responsibilities fall to the copy and
1450 which fall to the fixup is up to the author of those functions.
1452 See the comments in gdbarch.sh for details.
1454 Note that displaced stepping and software single-step cannot
1455 currently be used in combination, although with some care I think
1456 they could be made to. Software single-step works by placing
1457 breakpoints on all possible subsequent instructions; if the
1458 displaced instruction is a PC-relative jump, those breakpoints
1459 could fall in very strange places --- on pages that aren't
1460 executable, or at addresses that are not proper instruction
1461 boundaries. (We do generally let other threads run while we wait
1462 to hit the software single-step breakpoint, and they might
1463 encounter such a corrupted instruction.) One way to work around
1464 this would be to have gdbarch_displaced_step_copy_insn fully
1465 simulate the effect of PC-relative instructions (and return NULL)
1466 on architectures that use software single-stepping.
1468 In non-stop mode, we can have independent and simultaneous step
1469 requests, so more than one thread may need to simultaneously step
1470 over a breakpoint. The current implementation assumes there is
1471 only one scratch space per process. In this case, we have to
1472 serialize access to the scratch space. If thread A wants to step
1473 over a breakpoint, but we are currently waiting for some other
1474 thread to complete a displaced step, we leave thread A stopped and
1475 place it in the displaced_step_request_queue. Whenever a displaced
1476 step finishes, we pick the next thread in the queue and start a new
1477 displaced step operation on it. See displaced_step_prepare and
1478 displaced_step_fixup for details. */
1480 /* Per-inferior displaced stepping state. */
1481 struct displaced_step_inferior_state
1483 /* Pointer to next in linked list. */
1484 struct displaced_step_inferior_state
*next
;
1486 /* The process this displaced step state refers to. */
1489 /* True if preparing a displaced step ever failed. If so, we won't
1490 try displaced stepping for this inferior again. */
1493 /* If this is not null_ptid, this is the thread carrying out a
1494 displaced single-step in process PID. This thread's state will
1495 require fixing up once it has completed its step. */
1498 /* The architecture the thread had when we stepped it. */
1499 struct gdbarch
*step_gdbarch
;
1501 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1502 for post-step cleanup. */
1503 struct displaced_step_closure
*step_closure
;
1505 /* The address of the original instruction, and the copy we
1507 CORE_ADDR step_original
, step_copy
;
1509 /* Saved contents of copy area. */
1510 gdb_byte
*step_saved_copy
;
1513 /* The list of states of processes involved in displaced stepping
1515 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1517 /* Get the displaced stepping state of process PID. */
1519 static struct displaced_step_inferior_state
*
1520 get_displaced_stepping_state (int pid
)
1522 struct displaced_step_inferior_state
*state
;
1524 for (state
= displaced_step_inferior_states
;
1526 state
= state
->next
)
1527 if (state
->pid
== pid
)
1533 /* Returns true if any inferior has a thread doing a displaced
1537 displaced_step_in_progress_any_inferior (void)
1539 struct displaced_step_inferior_state
*state
;
1541 for (state
= displaced_step_inferior_states
;
1543 state
= state
->next
)
1544 if (!ptid_equal (state
->step_ptid
, null_ptid
))
1550 /* Return true if thread represented by PTID is doing a displaced
1554 displaced_step_in_progress_thread (ptid_t ptid
)
1556 struct displaced_step_inferior_state
*displaced
;
1558 gdb_assert (!ptid_equal (ptid
, null_ptid
));
1560 displaced
= get_displaced_stepping_state (ptid_get_pid (ptid
));
1562 return (displaced
!= NULL
&& ptid_equal (displaced
->step_ptid
, ptid
));
1565 /* Return true if process PID has a thread doing a displaced step. */
1568 displaced_step_in_progress (int pid
)
1570 struct displaced_step_inferior_state
*displaced
;
1572 displaced
= get_displaced_stepping_state (pid
);
1573 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1579 /* Add a new displaced stepping state for process PID to the displaced
1580 stepping state list, or return a pointer to an already existing
1581 entry, if it already exists. Never returns NULL. */
1583 static struct displaced_step_inferior_state
*
1584 add_displaced_stepping_state (int pid
)
1586 struct displaced_step_inferior_state
*state
;
1588 for (state
= displaced_step_inferior_states
;
1590 state
= state
->next
)
1591 if (state
->pid
== pid
)
1594 state
= XCNEW (struct displaced_step_inferior_state
);
1596 state
->next
= displaced_step_inferior_states
;
1597 displaced_step_inferior_states
= state
;
1602 /* If inferior is in displaced stepping, and ADDR equals to starting address
1603 of copy area, return corresponding displaced_step_closure. Otherwise,
1606 struct displaced_step_closure
*
1607 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1609 struct displaced_step_inferior_state
*displaced
1610 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1612 /* If checking the mode of displaced instruction in copy area. */
1613 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1614 && (displaced
->step_copy
== addr
))
1615 return displaced
->step_closure
;
1620 /* Remove the displaced stepping state of process PID. */
1623 remove_displaced_stepping_state (int pid
)
1625 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1627 gdb_assert (pid
!= 0);
1629 it
= displaced_step_inferior_states
;
1630 prev_next_p
= &displaced_step_inferior_states
;
1635 *prev_next_p
= it
->next
;
1640 prev_next_p
= &it
->next
;
1646 infrun_inferior_exit (struct inferior
*inf
)
1648 remove_displaced_stepping_state (inf
->pid
);
1651 /* If ON, and the architecture supports it, GDB will use displaced
1652 stepping to step over breakpoints. If OFF, or if the architecture
1653 doesn't support it, GDB will instead use the traditional
1654 hold-and-step approach. If AUTO (which is the default), GDB will
1655 decide which technique to use to step over breakpoints depending on
1656 which of all-stop or non-stop mode is active --- displaced stepping
1657 in non-stop mode; hold-and-step in all-stop mode. */
1659 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1662 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1663 struct cmd_list_element
*c
,
1666 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1667 fprintf_filtered (file
,
1668 _("Debugger's willingness to use displaced stepping "
1669 "to step over breakpoints is %s (currently %s).\n"),
1670 value
, target_is_non_stop_p () ? "on" : "off");
1672 fprintf_filtered (file
,
1673 _("Debugger's willingness to use displaced stepping "
1674 "to step over breakpoints is %s.\n"), value
);
1677 /* Return non-zero if displaced stepping can/should be used to step
1678 over breakpoints of thread TP. */
1681 use_displaced_stepping (struct thread_info
*tp
)
1683 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
1684 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1685 struct displaced_step_inferior_state
*displaced_state
;
1687 displaced_state
= get_displaced_stepping_state (ptid_get_pid (tp
->ptid
));
1689 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1690 && target_is_non_stop_p ())
1691 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1692 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1693 && find_record_target () == NULL
1694 && (displaced_state
== NULL
1695 || !displaced_state
->failed_before
));
1698 /* Clean out any stray displaced stepping state. */
1700 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1702 /* Indicate that there is no cleanup pending. */
1703 displaced
->step_ptid
= null_ptid
;
1705 if (displaced
->step_closure
)
1707 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1708 displaced
->step_closure
);
1709 displaced
->step_closure
= NULL
;
1714 displaced_step_clear_cleanup (void *arg
)
1716 struct displaced_step_inferior_state
*state
1717 = (struct displaced_step_inferior_state
*) arg
;
1719 displaced_step_clear (state
);
1722 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1724 displaced_step_dump_bytes (struct ui_file
*file
,
1725 const gdb_byte
*buf
,
1730 for (i
= 0; i
< len
; i
++)
1731 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1732 fputs_unfiltered ("\n", file
);
1735 /* Prepare to single-step, using displaced stepping.
1737 Note that we cannot use displaced stepping when we have a signal to
1738 deliver. If we have a signal to deliver and an instruction to step
1739 over, then after the step, there will be no indication from the
1740 target whether the thread entered a signal handler or ignored the
1741 signal and stepped over the instruction successfully --- both cases
1742 result in a simple SIGTRAP. In the first case we mustn't do a
1743 fixup, and in the second case we must --- but we can't tell which.
1744 Comments in the code for 'random signals' in handle_inferior_event
1745 explain how we handle this case instead.
1747 Returns 1 if preparing was successful -- this thread is going to be
1748 stepped now; 0 if displaced stepping this thread got queued; or -1
1749 if this instruction can't be displaced stepped. */
1752 displaced_step_prepare_throw (ptid_t ptid
)
1754 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1755 struct thread_info
*tp
= find_thread_ptid (ptid
);
1756 struct regcache
*regcache
= get_thread_regcache (ptid
);
1757 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1758 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1759 CORE_ADDR original
, copy
;
1761 struct displaced_step_closure
*closure
;
1762 struct displaced_step_inferior_state
*displaced
;
1765 /* We should never reach this function if the architecture does not
1766 support displaced stepping. */
1767 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1769 /* Nor if the thread isn't meant to step over a breakpoint. */
1770 gdb_assert (tp
->control
.trap_expected
);
1772 /* Disable range stepping while executing in the scratch pad. We
1773 want a single-step even if executing the displaced instruction in
1774 the scratch buffer lands within the stepping range (e.g., a
1776 tp
->control
.may_range_step
= 0;
1778 /* We have to displaced step one thread at a time, as we only have
1779 access to a single scratch space per inferior. */
1781 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1783 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1785 /* Already waiting for a displaced step to finish. Defer this
1786 request and place in queue. */
1788 if (debug_displaced
)
1789 fprintf_unfiltered (gdb_stdlog
,
1790 "displaced: deferring step of %s\n",
1791 target_pid_to_str (ptid
));
1793 thread_step_over_chain_enqueue (tp
);
1798 if (debug_displaced
)
1799 fprintf_unfiltered (gdb_stdlog
,
1800 "displaced: stepping %s now\n",
1801 target_pid_to_str (ptid
));
1804 displaced_step_clear (displaced
);
1806 old_cleanups
= save_inferior_ptid ();
1807 inferior_ptid
= ptid
;
1809 original
= regcache_read_pc (regcache
);
1811 copy
= gdbarch_displaced_step_location (gdbarch
);
1812 len
= gdbarch_max_insn_length (gdbarch
);
1814 if (breakpoint_in_range_p (aspace
, copy
, len
))
1816 /* There's a breakpoint set in the scratch pad location range
1817 (which is usually around the entry point). We'd either
1818 install it before resuming, which would overwrite/corrupt the
1819 scratch pad, or if it was already inserted, this displaced
1820 step would overwrite it. The latter is OK in the sense that
1821 we already assume that no thread is going to execute the code
1822 in the scratch pad range (after initial startup) anyway, but
1823 the former is unacceptable. Simply punt and fallback to
1824 stepping over this breakpoint in-line. */
1825 if (debug_displaced
)
1827 fprintf_unfiltered (gdb_stdlog
,
1828 "displaced: breakpoint set in scratch pad. "
1829 "Stepping over breakpoint in-line instead.\n");
1832 do_cleanups (old_cleanups
);
1836 /* Save the original contents of the copy area. */
1837 displaced
->step_saved_copy
= (gdb_byte
*) xmalloc (len
);
1838 ignore_cleanups
= make_cleanup (free_current_contents
,
1839 &displaced
->step_saved_copy
);
1840 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1842 throw_error (MEMORY_ERROR
,
1843 _("Error accessing memory address %s (%s) for "
1844 "displaced-stepping scratch space."),
1845 paddress (gdbarch
, copy
), safe_strerror (status
));
1846 if (debug_displaced
)
1848 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1849 paddress (gdbarch
, copy
));
1850 displaced_step_dump_bytes (gdb_stdlog
,
1851 displaced
->step_saved_copy
,
1855 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1856 original
, copy
, regcache
);
1857 if (closure
== NULL
)
1859 /* The architecture doesn't know how or want to displaced step
1860 this instruction or instruction sequence. Fallback to
1861 stepping over the breakpoint in-line. */
1862 do_cleanups (old_cleanups
);
1866 /* Save the information we need to fix things up if the step
1868 displaced
->step_ptid
= ptid
;
1869 displaced
->step_gdbarch
= gdbarch
;
1870 displaced
->step_closure
= closure
;
1871 displaced
->step_original
= original
;
1872 displaced
->step_copy
= copy
;
1874 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1876 /* Resume execution at the copy. */
1877 regcache_write_pc (regcache
, copy
);
1879 discard_cleanups (ignore_cleanups
);
1881 do_cleanups (old_cleanups
);
1883 if (debug_displaced
)
1884 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1885 paddress (gdbarch
, copy
));
1890 /* Wrapper for displaced_step_prepare_throw that disabled further
1891 attempts at displaced stepping if we get a memory error. */
1894 displaced_step_prepare (ptid_t ptid
)
1900 prepared
= displaced_step_prepare_throw (ptid
);
1902 CATCH (ex
, RETURN_MASK_ERROR
)
1904 struct displaced_step_inferior_state
*displaced_state
;
1906 if (ex
.error
!= MEMORY_ERROR
1907 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1908 throw_exception (ex
);
1912 fprintf_unfiltered (gdb_stdlog
,
1913 "infrun: disabling displaced stepping: %s\n",
1917 /* Be verbose if "set displaced-stepping" is "on", silent if
1919 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1921 warning (_("disabling displaced stepping: %s"),
1925 /* Disable further displaced stepping attempts. */
1927 = get_displaced_stepping_state (ptid_get_pid (ptid
));
1928 displaced_state
->failed_before
= 1;
1936 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1937 const gdb_byte
*myaddr
, int len
)
1939 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1941 inferior_ptid
= ptid
;
1942 write_memory (memaddr
, myaddr
, len
);
1943 do_cleanups (ptid_cleanup
);
1946 /* Restore the contents of the copy area for thread PTID. */
1949 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1952 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1954 write_memory_ptid (ptid
, displaced
->step_copy
,
1955 displaced
->step_saved_copy
, len
);
1956 if (debug_displaced
)
1957 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1958 target_pid_to_str (ptid
),
1959 paddress (displaced
->step_gdbarch
,
1960 displaced
->step_copy
));
1963 /* If we displaced stepped an instruction successfully, adjust
1964 registers and memory to yield the same effect the instruction would
1965 have had if we had executed it at its original address, and return
1966 1. If the instruction didn't complete, relocate the PC and return
1967 -1. If the thread wasn't displaced stepping, return 0. */
1970 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1972 struct cleanup
*old_cleanups
;
1973 struct displaced_step_inferior_state
*displaced
1974 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1977 /* Was any thread of this process doing a displaced step? */
1978 if (displaced
== NULL
)
1981 /* Was this event for the pid we displaced? */
1982 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1983 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1986 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1988 displaced_step_restore (displaced
, displaced
->step_ptid
);
1990 /* Fixup may need to read memory/registers. Switch to the thread
1991 that we're fixing up. Also, target_stopped_by_watchpoint checks
1992 the current thread. */
1993 switch_to_thread (event_ptid
);
1995 /* Did the instruction complete successfully? */
1996 if (signal
== GDB_SIGNAL_TRAP
1997 && !(target_stopped_by_watchpoint ()
1998 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1999 || target_have_steppable_watchpoint
)))
2001 /* Fix up the resulting state. */
2002 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
2003 displaced
->step_closure
,
2004 displaced
->step_original
,
2005 displaced
->step_copy
,
2006 get_thread_regcache (displaced
->step_ptid
));
2011 /* Since the instruction didn't complete, all we can do is
2013 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
2014 CORE_ADDR pc
= regcache_read_pc (regcache
);
2016 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
2017 regcache_write_pc (regcache
, pc
);
2021 do_cleanups (old_cleanups
);
2023 displaced
->step_ptid
= null_ptid
;
2028 /* Data to be passed around while handling an event. This data is
2029 discarded between events. */
2030 struct execution_control_state
2033 /* The thread that got the event, if this was a thread event; NULL
2035 struct thread_info
*event_thread
;
2037 struct target_waitstatus ws
;
2038 int stop_func_filled_in
;
2039 CORE_ADDR stop_func_start
;
2040 CORE_ADDR stop_func_end
;
2041 const char *stop_func_name
;
2044 /* True if the event thread hit the single-step breakpoint of
2045 another thread. Thus the event doesn't cause a stop, the thread
2046 needs to be single-stepped past the single-step breakpoint before
2047 we can switch back to the original stepping thread. */
2048 int hit_singlestep_breakpoint
;
2051 /* Clear ECS and set it to point at TP. */
2054 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
2056 memset (ecs
, 0, sizeof (*ecs
));
2057 ecs
->event_thread
= tp
;
2058 ecs
->ptid
= tp
->ptid
;
2061 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
2062 static void prepare_to_wait (struct execution_control_state
*ecs
);
2063 static int keep_going_stepped_thread (struct thread_info
*tp
);
2064 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
2066 /* Are there any pending step-over requests? If so, run all we can
2067 now and return true. Otherwise, return false. */
2070 start_step_over (void)
2072 struct thread_info
*tp
, *next
;
2074 /* Don't start a new step-over if we already have an in-line
2075 step-over operation ongoing. */
2076 if (step_over_info_valid_p ())
2079 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
2081 struct execution_control_state ecss
;
2082 struct execution_control_state
*ecs
= &ecss
;
2083 step_over_what step_what
;
2084 int must_be_in_line
;
2086 gdb_assert (!tp
->stop_requested
);
2088 next
= thread_step_over_chain_next (tp
);
2090 /* If this inferior already has a displaced step in process,
2091 don't start a new one. */
2092 if (displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2095 step_what
= thread_still_needs_step_over (tp
);
2096 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
2097 || ((step_what
& STEP_OVER_BREAKPOINT
)
2098 && !use_displaced_stepping (tp
)));
2100 /* We currently stop all threads of all processes to step-over
2101 in-line. If we need to start a new in-line step-over, let
2102 any pending displaced steps finish first. */
2103 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
2106 thread_step_over_chain_remove (tp
);
2108 if (step_over_queue_head
== NULL
)
2111 fprintf_unfiltered (gdb_stdlog
,
2112 "infrun: step-over queue now empty\n");
2115 if (tp
->control
.trap_expected
2119 internal_error (__FILE__
, __LINE__
,
2120 "[%s] has inconsistent state: "
2121 "trap_expected=%d, resumed=%d, executing=%d\n",
2122 target_pid_to_str (tp
->ptid
),
2123 tp
->control
.trap_expected
,
2129 fprintf_unfiltered (gdb_stdlog
,
2130 "infrun: resuming [%s] for step-over\n",
2131 target_pid_to_str (tp
->ptid
));
2133 /* keep_going_pass_signal skips the step-over if the breakpoint
2134 is no longer inserted. In all-stop, we want to keep looking
2135 for a thread that needs a step-over instead of resuming TP,
2136 because we wouldn't be able to resume anything else until the
2137 target stops again. In non-stop, the resume always resumes
2138 only TP, so it's OK to let the thread resume freely. */
2139 if (!target_is_non_stop_p () && !step_what
)
2142 switch_to_thread (tp
->ptid
);
2143 reset_ecs (ecs
, tp
);
2144 keep_going_pass_signal (ecs
);
2146 if (!ecs
->wait_some_more
)
2147 error (_("Command aborted."));
2149 gdb_assert (tp
->resumed
);
2151 /* If we started a new in-line step-over, we're done. */
2152 if (step_over_info_valid_p ())
2154 gdb_assert (tp
->control
.trap_expected
);
2158 if (!target_is_non_stop_p ())
2160 /* On all-stop, shouldn't have resumed unless we needed a
2162 gdb_assert (tp
->control
.trap_expected
2163 || tp
->step_after_step_resume_breakpoint
);
2165 /* With remote targets (at least), in all-stop, we can't
2166 issue any further remote commands until the program stops
2171 /* Either the thread no longer needed a step-over, or a new
2172 displaced stepping sequence started. Even in the latter
2173 case, continue looking. Maybe we can also start another
2174 displaced step on a thread of other process. */
2180 /* Update global variables holding ptids to hold NEW_PTID if they were
2181 holding OLD_PTID. */
2183 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2185 struct displaced_step_inferior_state
*displaced
;
2187 if (ptid_equal (inferior_ptid
, old_ptid
))
2188 inferior_ptid
= new_ptid
;
2190 for (displaced
= displaced_step_inferior_states
;
2192 displaced
= displaced
->next
)
2194 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
2195 displaced
->step_ptid
= new_ptid
;
2202 /* Things to clean up if we QUIT out of resume (). */
2204 resume_cleanups (void *ignore
)
2206 if (!ptid_equal (inferior_ptid
, null_ptid
))
2207 delete_single_step_breakpoints (inferior_thread ());
2212 static const char schedlock_off
[] = "off";
2213 static const char schedlock_on
[] = "on";
2214 static const char schedlock_step
[] = "step";
2215 static const char schedlock_replay
[] = "replay";
2216 static const char *const scheduler_enums
[] = {
2223 static const char *scheduler_mode
= schedlock_replay
;
2225 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2226 struct cmd_list_element
*c
, const char *value
)
2228 fprintf_filtered (file
,
2229 _("Mode for locking scheduler "
2230 "during execution is \"%s\".\n"),
2235 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
2237 if (!target_can_lock_scheduler
)
2239 scheduler_mode
= schedlock_off
;
2240 error (_("Target '%s' cannot support this command."), target_shortname
);
2244 /* True if execution commands resume all threads of all processes by
2245 default; otherwise, resume only threads of the current inferior
2247 int sched_multi
= 0;
2249 /* Try to setup for software single stepping over the specified location.
2250 Return 1 if target_resume() should use hardware single step.
2252 GDBARCH the current gdbarch.
2253 PC the location to step over. */
2256 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2260 if (execution_direction
== EXEC_FORWARD
2261 && gdbarch_software_single_step_p (gdbarch
))
2262 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2270 user_visible_resume_ptid (int step
)
2276 /* With non-stop mode on, threads are always handled
2278 resume_ptid
= inferior_ptid
;
2280 else if ((scheduler_mode
== schedlock_on
)
2281 || (scheduler_mode
== schedlock_step
&& step
))
2283 /* User-settable 'scheduler' mode requires solo thread
2285 resume_ptid
= inferior_ptid
;
2287 else if ((scheduler_mode
== schedlock_replay
)
2288 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2290 /* User-settable 'scheduler' mode requires solo thread resume in replay
2292 resume_ptid
= inferior_ptid
;
2294 else if (!sched_multi
&& target_supports_multi_process ())
2296 /* Resume all threads of the current process (and none of other
2298 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2302 /* Resume all threads of all processes. */
2303 resume_ptid
= RESUME_ALL
;
2309 /* Return a ptid representing the set of threads that we will resume,
2310 in the perspective of the target, assuming run control handling
2311 does not require leaving some threads stopped (e.g., stepping past
2312 breakpoint). USER_STEP indicates whether we're about to start the
2313 target for a stepping command. */
2316 internal_resume_ptid (int user_step
)
2318 /* In non-stop, we always control threads individually. Note that
2319 the target may always work in non-stop mode even with "set
2320 non-stop off", in which case user_visible_resume_ptid could
2321 return a wildcard ptid. */
2322 if (target_is_non_stop_p ())
2323 return inferior_ptid
;
2325 return user_visible_resume_ptid (user_step
);
2328 /* Wrapper for target_resume, that handles infrun-specific
2332 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2334 struct thread_info
*tp
= inferior_thread ();
2336 gdb_assert (!tp
->stop_requested
);
2338 /* Install inferior's terminal modes. */
2339 target_terminal_inferior ();
2341 /* Avoid confusing the next resume, if the next stop/resume
2342 happens to apply to another thread. */
2343 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2345 /* Advise target which signals may be handled silently.
2347 If we have removed breakpoints because we are stepping over one
2348 in-line (in any thread), we need to receive all signals to avoid
2349 accidentally skipping a breakpoint during execution of a signal
2352 Likewise if we're displaced stepping, otherwise a trap for a
2353 breakpoint in a signal handler might be confused with the
2354 displaced step finishing. We don't make the displaced_step_fixup
2355 step distinguish the cases instead, because:
2357 - a backtrace while stopped in the signal handler would show the
2358 scratch pad as frame older than the signal handler, instead of
2359 the real mainline code.
2361 - when the thread is later resumed, the signal handler would
2362 return to the scratch pad area, which would no longer be
2364 if (step_over_info_valid_p ()
2365 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2366 target_pass_signals (0, NULL
);
2368 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2370 target_resume (resume_ptid
, step
, sig
);
2372 target_commit_resume ();
2375 /* Resume the inferior, but allow a QUIT. This is useful if the user
2376 wants to interrupt some lengthy single-stepping operation
2377 (for child processes, the SIGINT goes to the inferior, and so
2378 we get a SIGINT random_signal, but for remote debugging and perhaps
2379 other targets, that's not true).
2381 SIG is the signal to give the inferior (zero for none). */
2383 resume (enum gdb_signal sig
)
2385 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2386 struct regcache
*regcache
= get_current_regcache ();
2387 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2388 struct thread_info
*tp
= inferior_thread ();
2389 CORE_ADDR pc
= regcache_read_pc (regcache
);
2390 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2392 /* This represents the user's step vs continue request. When
2393 deciding whether "set scheduler-locking step" applies, it's the
2394 user's intention that counts. */
2395 const int user_step
= tp
->control
.stepping_command
;
2396 /* This represents what we'll actually request the target to do.
2397 This can decay from a step to a continue, if e.g., we need to
2398 implement single-stepping with breakpoints (software
2402 gdb_assert (!tp
->stop_requested
);
2403 gdb_assert (!thread_is_in_step_over_chain (tp
));
2407 if (tp
->suspend
.waitstatus_pending_p
)
2413 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2414 fprintf_unfiltered (gdb_stdlog
,
2415 "infrun: resume: thread %s has pending wait status %s "
2416 "(currently_stepping=%d).\n",
2417 target_pid_to_str (tp
->ptid
), statstr
,
2418 currently_stepping (tp
));
2424 /* FIXME: What should we do if we are supposed to resume this
2425 thread with a signal? Maybe we should maintain a queue of
2426 pending signals to deliver. */
2427 if (sig
!= GDB_SIGNAL_0
)
2429 warning (_("Couldn't deliver signal %s to %s."),
2430 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2433 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2434 discard_cleanups (old_cleanups
);
2436 if (target_can_async_p ())
2441 tp
->stepped_breakpoint
= 0;
2443 /* Depends on stepped_breakpoint. */
2444 step
= currently_stepping (tp
);
2446 if (current_inferior ()->waiting_for_vfork_done
)
2448 /* Don't try to single-step a vfork parent that is waiting for
2449 the child to get out of the shared memory region (by exec'ing
2450 or exiting). This is particularly important on software
2451 single-step archs, as the child process would trip on the
2452 software single step breakpoint inserted for the parent
2453 process. Since the parent will not actually execute any
2454 instruction until the child is out of the shared region (such
2455 are vfork's semantics), it is safe to simply continue it.
2456 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2457 the parent, and tell it to `keep_going', which automatically
2458 re-sets it stepping. */
2460 fprintf_unfiltered (gdb_stdlog
,
2461 "infrun: resume : clear step\n");
2466 fprintf_unfiltered (gdb_stdlog
,
2467 "infrun: resume (step=%d, signal=%s), "
2468 "trap_expected=%d, current thread [%s] at %s\n",
2469 step
, gdb_signal_to_symbol_string (sig
),
2470 tp
->control
.trap_expected
,
2471 target_pid_to_str (inferior_ptid
),
2472 paddress (gdbarch
, pc
));
2474 /* Normally, by the time we reach `resume', the breakpoints are either
2475 removed or inserted, as appropriate. The exception is if we're sitting
2476 at a permanent breakpoint; we need to step over it, but permanent
2477 breakpoints can't be removed. So we have to test for it here. */
2478 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2480 if (sig
!= GDB_SIGNAL_0
)
2482 /* We have a signal to pass to the inferior. The resume
2483 may, or may not take us to the signal handler. If this
2484 is a step, we'll need to stop in the signal handler, if
2485 there's one, (if the target supports stepping into
2486 handlers), or in the next mainline instruction, if
2487 there's no handler. If this is a continue, we need to be
2488 sure to run the handler with all breakpoints inserted.
2489 In all cases, set a breakpoint at the current address
2490 (where the handler returns to), and once that breakpoint
2491 is hit, resume skipping the permanent breakpoint. If
2492 that breakpoint isn't hit, then we've stepped into the
2493 signal handler (or hit some other event). We'll delete
2494 the step-resume breakpoint then. */
2497 fprintf_unfiltered (gdb_stdlog
,
2498 "infrun: resume: skipping permanent breakpoint, "
2499 "deliver signal first\n");
2501 clear_step_over_info ();
2502 tp
->control
.trap_expected
= 0;
2504 if (tp
->control
.step_resume_breakpoint
== NULL
)
2506 /* Set a "high-priority" step-resume, as we don't want
2507 user breakpoints at PC to trigger (again) when this
2509 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2510 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2512 tp
->step_after_step_resume_breakpoint
= step
;
2515 insert_breakpoints ();
2519 /* There's no signal to pass, we can go ahead and skip the
2520 permanent breakpoint manually. */
2522 fprintf_unfiltered (gdb_stdlog
,
2523 "infrun: resume: skipping permanent breakpoint\n");
2524 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2525 /* Update pc to reflect the new address from which we will
2526 execute instructions. */
2527 pc
= regcache_read_pc (regcache
);
2531 /* We've already advanced the PC, so the stepping part
2532 is done. Now we need to arrange for a trap to be
2533 reported to handle_inferior_event. Set a breakpoint
2534 at the current PC, and run to it. Don't update
2535 prev_pc, because if we end in
2536 switch_back_to_stepped_thread, we want the "expected
2537 thread advanced also" branch to be taken. IOW, we
2538 don't want this thread to step further from PC
2540 gdb_assert (!step_over_info_valid_p ());
2541 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2542 insert_breakpoints ();
2544 resume_ptid
= internal_resume_ptid (user_step
);
2545 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2546 discard_cleanups (old_cleanups
);
2553 /* If we have a breakpoint to step over, make sure to do a single
2554 step only. Same if we have software watchpoints. */
2555 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2556 tp
->control
.may_range_step
= 0;
2558 /* If enabled, step over breakpoints by executing a copy of the
2559 instruction at a different address.
2561 We can't use displaced stepping when we have a signal to deliver;
2562 the comments for displaced_step_prepare explain why. The
2563 comments in the handle_inferior event for dealing with 'random
2564 signals' explain what we do instead.
2566 We can't use displaced stepping when we are waiting for vfork_done
2567 event, displaced stepping breaks the vfork child similarly as single
2568 step software breakpoint. */
2569 if (tp
->control
.trap_expected
2570 && use_displaced_stepping (tp
)
2571 && !step_over_info_valid_p ()
2572 && sig
== GDB_SIGNAL_0
2573 && !current_inferior ()->waiting_for_vfork_done
)
2575 int prepared
= displaced_step_prepare (inferior_ptid
);
2580 fprintf_unfiltered (gdb_stdlog
,
2581 "Got placed in step-over queue\n");
2583 tp
->control
.trap_expected
= 0;
2584 discard_cleanups (old_cleanups
);
2587 else if (prepared
< 0)
2589 /* Fallback to stepping over the breakpoint in-line. */
2591 if (target_is_non_stop_p ())
2592 stop_all_threads ();
2594 set_step_over_info (get_regcache_aspace (regcache
),
2595 regcache_read_pc (regcache
), 0, tp
->global_num
);
2597 step
= maybe_software_singlestep (gdbarch
, pc
);
2599 insert_breakpoints ();
2601 else if (prepared
> 0)
2603 struct displaced_step_inferior_state
*displaced
;
2605 /* Update pc to reflect the new address from which we will
2606 execute instructions due to displaced stepping. */
2607 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2609 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2610 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2611 displaced
->step_closure
);
2615 /* Do we need to do it the hard way, w/temp breakpoints? */
2617 step
= maybe_software_singlestep (gdbarch
, pc
);
2619 /* Currently, our software single-step implementation leads to different
2620 results than hardware single-stepping in one situation: when stepping
2621 into delivering a signal which has an associated signal handler,
2622 hardware single-step will stop at the first instruction of the handler,
2623 while software single-step will simply skip execution of the handler.
2625 For now, this difference in behavior is accepted since there is no
2626 easy way to actually implement single-stepping into a signal handler
2627 without kernel support.
2629 However, there is one scenario where this difference leads to follow-on
2630 problems: if we're stepping off a breakpoint by removing all breakpoints
2631 and then single-stepping. In this case, the software single-step
2632 behavior means that even if there is a *breakpoint* in the signal
2633 handler, GDB still would not stop.
2635 Fortunately, we can at least fix this particular issue. We detect
2636 here the case where we are about to deliver a signal while software
2637 single-stepping with breakpoints removed. In this situation, we
2638 revert the decisions to remove all breakpoints and insert single-
2639 step breakpoints, and instead we install a step-resume breakpoint
2640 at the current address, deliver the signal without stepping, and
2641 once we arrive back at the step-resume breakpoint, actually step
2642 over the breakpoint we originally wanted to step over. */
2643 if (thread_has_single_step_breakpoints_set (tp
)
2644 && sig
!= GDB_SIGNAL_0
2645 && step_over_info_valid_p ())
2647 /* If we have nested signals or a pending signal is delivered
2648 immediately after a handler returns, might might already have
2649 a step-resume breakpoint set on the earlier handler. We cannot
2650 set another step-resume breakpoint; just continue on until the
2651 original breakpoint is hit. */
2652 if (tp
->control
.step_resume_breakpoint
== NULL
)
2654 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2655 tp
->step_after_step_resume_breakpoint
= 1;
2658 delete_single_step_breakpoints (tp
);
2660 clear_step_over_info ();
2661 tp
->control
.trap_expected
= 0;
2663 insert_breakpoints ();
2666 /* If STEP is set, it's a request to use hardware stepping
2667 facilities. But in that case, we should never
2668 use singlestep breakpoint. */
2669 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2671 /* Decide the set of threads to ask the target to resume. */
2672 if (tp
->control
.trap_expected
)
2674 /* We're allowing a thread to run past a breakpoint it has
2675 hit, either by single-stepping the thread with the breakpoint
2676 removed, or by displaced stepping, with the breakpoint inserted.
2677 In the former case, we need to single-step only this thread,
2678 and keep others stopped, as they can miss this breakpoint if
2679 allowed to run. That's not really a problem for displaced
2680 stepping, but, we still keep other threads stopped, in case
2681 another thread is also stopped for a breakpoint waiting for
2682 its turn in the displaced stepping queue. */
2683 resume_ptid
= inferior_ptid
;
2686 resume_ptid
= internal_resume_ptid (user_step
);
2688 if (execution_direction
!= EXEC_REVERSE
2689 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2691 /* There are two cases where we currently need to step a
2692 breakpoint instruction when we have a signal to deliver:
2694 - See handle_signal_stop where we handle random signals that
2695 could take out us out of the stepping range. Normally, in
2696 that case we end up continuing (instead of stepping) over the
2697 signal handler with a breakpoint at PC, but there are cases
2698 where we should _always_ single-step, even if we have a
2699 step-resume breakpoint, like when a software watchpoint is
2700 set. Assuming single-stepping and delivering a signal at the
2701 same time would takes us to the signal handler, then we could
2702 have removed the breakpoint at PC to step over it. However,
2703 some hardware step targets (like e.g., Mac OS) can't step
2704 into signal handlers, and for those, we need to leave the
2705 breakpoint at PC inserted, as otherwise if the handler
2706 recurses and executes PC again, it'll miss the breakpoint.
2707 So we leave the breakpoint inserted anyway, but we need to
2708 record that we tried to step a breakpoint instruction, so
2709 that adjust_pc_after_break doesn't end up confused.
2711 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2712 in one thread after another thread that was stepping had been
2713 momentarily paused for a step-over. When we re-resume the
2714 stepping thread, it may be resumed from that address with a
2715 breakpoint that hasn't trapped yet. Seen with
2716 gdb.threads/non-stop-fair-events.exp, on targets that don't
2717 do displaced stepping. */
2720 fprintf_unfiltered (gdb_stdlog
,
2721 "infrun: resume: [%s] stepped breakpoint\n",
2722 target_pid_to_str (tp
->ptid
));
2724 tp
->stepped_breakpoint
= 1;
2726 /* Most targets can step a breakpoint instruction, thus
2727 executing it normally. But if this one cannot, just
2728 continue and we will hit it anyway. */
2729 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2734 && tp
->control
.trap_expected
2735 && use_displaced_stepping (tp
)
2736 && !step_over_info_valid_p ())
2738 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2739 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2740 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2743 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2744 paddress (resume_gdbarch
, actual_pc
));
2745 read_memory (actual_pc
, buf
, sizeof (buf
));
2746 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2749 if (tp
->control
.may_range_step
)
2751 /* If we're resuming a thread with the PC out of the step
2752 range, then we're doing some nested/finer run control
2753 operation, like stepping the thread out of the dynamic
2754 linker or the displaced stepping scratch pad. We
2755 shouldn't have allowed a range step then. */
2756 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2759 do_target_resume (resume_ptid
, step
, sig
);
2761 discard_cleanups (old_cleanups
);
2768 /* Counter that tracks number of user visible stops. This can be used
2769 to tell whether a command has proceeded the inferior past the
2770 current location. This allows e.g., inferior function calls in
2771 breakpoint commands to not interrupt the command list. When the
2772 call finishes successfully, the inferior is standing at the same
2773 breakpoint as if nothing happened (and so we don't call
2775 static ULONGEST current_stop_id
;
2782 return current_stop_id
;
2785 /* Called when we report a user visible stop. */
2793 /* Clear out all variables saying what to do when inferior is continued.
2794 First do this, then set the ones you want, then call `proceed'. */
2797 clear_proceed_status_thread (struct thread_info
*tp
)
2800 fprintf_unfiltered (gdb_stdlog
,
2801 "infrun: clear_proceed_status_thread (%s)\n",
2802 target_pid_to_str (tp
->ptid
));
2804 /* If we're starting a new sequence, then the previous finished
2805 single-step is no longer relevant. */
2806 if (tp
->suspend
.waitstatus_pending_p
)
2808 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2811 fprintf_unfiltered (gdb_stdlog
,
2812 "infrun: clear_proceed_status: pending "
2813 "event of %s was a finished step. "
2815 target_pid_to_str (tp
->ptid
));
2817 tp
->suspend
.waitstatus_pending_p
= 0;
2818 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2820 else if (debug_infrun
)
2824 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2825 fprintf_unfiltered (gdb_stdlog
,
2826 "infrun: clear_proceed_status_thread: thread %s "
2827 "has pending wait status %s "
2828 "(currently_stepping=%d).\n",
2829 target_pid_to_str (tp
->ptid
), statstr
,
2830 currently_stepping (tp
));
2835 /* If this signal should not be seen by program, give it zero.
2836 Used for debugging signals. */
2837 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2838 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2840 thread_fsm_delete (tp
->thread_fsm
);
2841 tp
->thread_fsm
= NULL
;
2843 tp
->control
.trap_expected
= 0;
2844 tp
->control
.step_range_start
= 0;
2845 tp
->control
.step_range_end
= 0;
2846 tp
->control
.may_range_step
= 0;
2847 tp
->control
.step_frame_id
= null_frame_id
;
2848 tp
->control
.step_stack_frame_id
= null_frame_id
;
2849 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2850 tp
->control
.step_start_function
= NULL
;
2851 tp
->stop_requested
= 0;
2853 tp
->control
.stop_step
= 0;
2855 tp
->control
.proceed_to_finish
= 0;
2857 tp
->control
.stepping_command
= 0;
2859 /* Discard any remaining commands or status from previous stop. */
2860 bpstat_clear (&tp
->control
.stop_bpstat
);
2864 clear_proceed_status (int step
)
2866 /* With scheduler-locking replay, stop replaying other threads if we're
2867 not replaying the user-visible resume ptid.
2869 This is a convenience feature to not require the user to explicitly
2870 stop replaying the other threads. We're assuming that the user's
2871 intent is to resume tracing the recorded process. */
2872 if (!non_stop
&& scheduler_mode
== schedlock_replay
2873 && target_record_is_replaying (minus_one_ptid
)
2874 && !target_record_will_replay (user_visible_resume_ptid (step
),
2875 execution_direction
))
2876 target_record_stop_replaying ();
2880 struct thread_info
*tp
;
2883 resume_ptid
= user_visible_resume_ptid (step
);
2885 /* In all-stop mode, delete the per-thread status of all threads
2886 we're about to resume, implicitly and explicitly. */
2887 ALL_NON_EXITED_THREADS (tp
)
2889 if (!ptid_match (tp
->ptid
, resume_ptid
))
2891 clear_proceed_status_thread (tp
);
2895 if (!ptid_equal (inferior_ptid
, null_ptid
))
2897 struct inferior
*inferior
;
2901 /* If in non-stop mode, only delete the per-thread status of
2902 the current thread. */
2903 clear_proceed_status_thread (inferior_thread ());
2906 inferior
= current_inferior ();
2907 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2910 observer_notify_about_to_proceed ();
2913 /* Returns true if TP is still stopped at a breakpoint that needs
2914 stepping-over in order to make progress. If the breakpoint is gone
2915 meanwhile, we can skip the whole step-over dance. */
2918 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2920 if (tp
->stepping_over_breakpoint
)
2922 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2924 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2925 regcache_read_pc (regcache
))
2926 == ordinary_breakpoint_here
)
2929 tp
->stepping_over_breakpoint
= 0;
2935 /* Check whether thread TP still needs to start a step-over in order
2936 to make progress when resumed. Returns an bitwise or of enum
2937 step_over_what bits, indicating what needs to be stepped over. */
2939 static step_over_what
2940 thread_still_needs_step_over (struct thread_info
*tp
)
2942 step_over_what what
= 0;
2944 if (thread_still_needs_step_over_bp (tp
))
2945 what
|= STEP_OVER_BREAKPOINT
;
2947 if (tp
->stepping_over_watchpoint
2948 && !target_have_steppable_watchpoint
)
2949 what
|= STEP_OVER_WATCHPOINT
;
2954 /* Returns true if scheduler locking applies. STEP indicates whether
2955 we're about to do a step/next-like command to a thread. */
2958 schedlock_applies (struct thread_info
*tp
)
2960 return (scheduler_mode
== schedlock_on
2961 || (scheduler_mode
== schedlock_step
2962 && tp
->control
.stepping_command
)
2963 || (scheduler_mode
== schedlock_replay
2964 && target_record_will_replay (minus_one_ptid
,
2965 execution_direction
)));
2968 /* Basic routine for continuing the program in various fashions.
2970 ADDR is the address to resume at, or -1 for resume where stopped.
2971 SIGGNAL is the signal to give it, or 0 for none,
2972 or -1 for act according to how it stopped.
2973 STEP is nonzero if should trap after one instruction.
2974 -1 means return after that and print nothing.
2975 You should probably set various step_... variables
2976 before calling here, if you are stepping.
2978 You should call clear_proceed_status before calling proceed. */
2981 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2983 struct regcache
*regcache
;
2984 struct gdbarch
*gdbarch
;
2985 struct thread_info
*tp
;
2987 struct address_space
*aspace
;
2989 struct execution_control_state ecss
;
2990 struct execution_control_state
*ecs
= &ecss
;
2991 struct cleanup
*old_chain
;
2992 struct cleanup
*defer_resume_cleanup
;
2995 /* If we're stopped at a fork/vfork, follow the branch set by the
2996 "set follow-fork-mode" command; otherwise, we'll just proceed
2997 resuming the current thread. */
2998 if (!follow_fork ())
3000 /* The target for some reason decided not to resume. */
3002 if (target_can_async_p ())
3003 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3007 /* We'll update this if & when we switch to a new thread. */
3008 previous_inferior_ptid
= inferior_ptid
;
3010 regcache
= get_current_regcache ();
3011 gdbarch
= get_regcache_arch (regcache
);
3012 aspace
= get_regcache_aspace (regcache
);
3013 pc
= regcache_read_pc (regcache
);
3014 tp
= inferior_thread ();
3016 /* Fill in with reasonable starting values. */
3017 init_thread_stepping_state (tp
);
3019 gdb_assert (!thread_is_in_step_over_chain (tp
));
3021 if (addr
== (CORE_ADDR
) -1)
3024 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3025 && execution_direction
!= EXEC_REVERSE
)
3026 /* There is a breakpoint at the address we will resume at,
3027 step one instruction before inserting breakpoints so that
3028 we do not stop right away (and report a second hit at this
3031 Note, we don't do this in reverse, because we won't
3032 actually be executing the breakpoint insn anyway.
3033 We'll be (un-)executing the previous instruction. */
3034 tp
->stepping_over_breakpoint
= 1;
3035 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3036 && gdbarch_single_step_through_delay (gdbarch
,
3037 get_current_frame ()))
3038 /* We stepped onto an instruction that needs to be stepped
3039 again before re-inserting the breakpoint, do so. */
3040 tp
->stepping_over_breakpoint
= 1;
3044 regcache_write_pc (regcache
, addr
);
3047 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3048 tp
->suspend
.stop_signal
= siggnal
;
3050 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3052 /* If an exception is thrown from this point on, make sure to
3053 propagate GDB's knowledge of the executing state to the
3054 frontend/user running state. */
3055 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3057 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3058 threads (e.g., we might need to set threads stepping over
3059 breakpoints first), from the user/frontend's point of view, all
3060 threads in RESUME_PTID are now running. Unless we're calling an
3061 inferior function, as in that case we pretend the inferior
3062 doesn't run at all. */
3063 if (!tp
->control
.in_infcall
)
3064 set_running (resume_ptid
, 1);
3067 fprintf_unfiltered (gdb_stdlog
,
3068 "infrun: proceed (addr=%s, signal=%s)\n",
3069 paddress (gdbarch
, addr
),
3070 gdb_signal_to_symbol_string (siggnal
));
3072 annotate_starting ();
3074 /* Make sure that output from GDB appears before output from the
3076 gdb_flush (gdb_stdout
);
3078 /* In a multi-threaded task we may select another thread and
3079 then continue or step.
3081 But if a thread that we're resuming had stopped at a breakpoint,
3082 it will immediately cause another breakpoint stop without any
3083 execution (i.e. it will report a breakpoint hit incorrectly). So
3084 we must step over it first.
3086 Look for threads other than the current (TP) that reported a
3087 breakpoint hit and haven't been resumed yet since. */
3089 /* If scheduler locking applies, we can avoid iterating over all
3091 if (!non_stop
&& !schedlock_applies (tp
))
3093 struct thread_info
*current
= tp
;
3095 ALL_NON_EXITED_THREADS (tp
)
3097 /* Ignore the current thread here. It's handled
3102 /* Ignore threads of processes we're not resuming. */
3103 if (!ptid_match (tp
->ptid
, resume_ptid
))
3106 if (!thread_still_needs_step_over (tp
))
3109 gdb_assert (!thread_is_in_step_over_chain (tp
));
3112 fprintf_unfiltered (gdb_stdlog
,
3113 "infrun: need to step-over [%s] first\n",
3114 target_pid_to_str (tp
->ptid
));
3116 thread_step_over_chain_enqueue (tp
);
3122 /* Enqueue the current thread last, so that we move all other
3123 threads over their breakpoints first. */
3124 if (tp
->stepping_over_breakpoint
)
3125 thread_step_over_chain_enqueue (tp
);
3127 /* If the thread isn't started, we'll still need to set its prev_pc,
3128 so that switch_back_to_stepped_thread knows the thread hasn't
3129 advanced. Must do this before resuming any thread, as in
3130 all-stop/remote, once we resume we can't send any other packet
3131 until the target stops again. */
3132 tp
->prev_pc
= regcache_read_pc (regcache
);
3134 defer_resume_cleanup
= make_cleanup_defer_target_commit_resume ();
3136 started
= start_step_over ();
3138 if (step_over_info_valid_p ())
3140 /* Either this thread started a new in-line step over, or some
3141 other thread was already doing one. In either case, don't
3142 resume anything else until the step-over is finished. */
3144 else if (started
&& !target_is_non_stop_p ())
3146 /* A new displaced stepping sequence was started. In all-stop,
3147 we can't talk to the target anymore until it next stops. */
3149 else if (!non_stop
&& target_is_non_stop_p ())
3151 /* In all-stop, but the target is always in non-stop mode.
3152 Start all other threads that are implicitly resumed too. */
3153 ALL_NON_EXITED_THREADS (tp
)
3155 /* Ignore threads of processes we're not resuming. */
3156 if (!ptid_match (tp
->ptid
, resume_ptid
))
3162 fprintf_unfiltered (gdb_stdlog
,
3163 "infrun: proceed: [%s] resumed\n",
3164 target_pid_to_str (tp
->ptid
));
3165 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3169 if (thread_is_in_step_over_chain (tp
))
3172 fprintf_unfiltered (gdb_stdlog
,
3173 "infrun: proceed: [%s] needs step-over\n",
3174 target_pid_to_str (tp
->ptid
));
3179 fprintf_unfiltered (gdb_stdlog
,
3180 "infrun: proceed: resuming %s\n",
3181 target_pid_to_str (tp
->ptid
));
3183 reset_ecs (ecs
, tp
);
3184 switch_to_thread (tp
->ptid
);
3185 keep_going_pass_signal (ecs
);
3186 if (!ecs
->wait_some_more
)
3187 error (_("Command aborted."));
3190 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3192 /* The thread wasn't started, and isn't queued, run it now. */
3193 reset_ecs (ecs
, tp
);
3194 switch_to_thread (tp
->ptid
);
3195 keep_going_pass_signal (ecs
);
3196 if (!ecs
->wait_some_more
)
3197 error (_("Command aborted."));
3200 do_cleanups (defer_resume_cleanup
);
3201 target_commit_resume ();
3203 discard_cleanups (old_chain
);
3205 /* Tell the event loop to wait for it to stop. If the target
3206 supports asynchronous execution, it'll do this from within
3208 if (!target_can_async_p ())
3209 mark_async_event_handler (infrun_async_inferior_event_token
);
3213 /* Start remote-debugging of a machine over a serial link. */
3216 start_remote (int from_tty
)
3218 struct inferior
*inferior
;
3220 inferior
= current_inferior ();
3221 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3223 /* Always go on waiting for the target, regardless of the mode. */
3224 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3225 indicate to wait_for_inferior that a target should timeout if
3226 nothing is returned (instead of just blocking). Because of this,
3227 targets expecting an immediate response need to, internally, set
3228 things up so that the target_wait() is forced to eventually
3230 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3231 differentiate to its caller what the state of the target is after
3232 the initial open has been performed. Here we're assuming that
3233 the target has stopped. It should be possible to eventually have
3234 target_open() return to the caller an indication that the target
3235 is currently running and GDB state should be set to the same as
3236 for an async run. */
3237 wait_for_inferior ();
3239 /* Now that the inferior has stopped, do any bookkeeping like
3240 loading shared libraries. We want to do this before normal_stop,
3241 so that the displayed frame is up to date. */
3242 post_create_inferior (¤t_target
, from_tty
);
3247 /* Initialize static vars when a new inferior begins. */
3250 init_wait_for_inferior (void)
3252 /* These are meaningless until the first time through wait_for_inferior. */
3254 breakpoint_init_inferior (inf_starting
);
3256 clear_proceed_status (0);
3258 target_last_wait_ptid
= minus_one_ptid
;
3260 previous_inferior_ptid
= inferior_ptid
;
3262 /* Discard any skipped inlined frames. */
3263 clear_inline_frame_state (minus_one_ptid
);
3268 static void handle_inferior_event (struct execution_control_state
*ecs
);
3270 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3271 struct execution_control_state
*ecs
);
3272 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3273 struct execution_control_state
*ecs
);
3274 static void handle_signal_stop (struct execution_control_state
*ecs
);
3275 static void check_exception_resume (struct execution_control_state
*,
3276 struct frame_info
*);
3278 static void end_stepping_range (struct execution_control_state
*ecs
);
3279 static void stop_waiting (struct execution_control_state
*ecs
);
3280 static void keep_going (struct execution_control_state
*ecs
);
3281 static void process_event_stop_test (struct execution_control_state
*ecs
);
3282 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3284 /* This function is attached as a "thread_stop_requested" observer.
3285 Cleanup local state that assumed the PTID was to be resumed, and
3286 report the stop to the frontend. */
3289 infrun_thread_stop_requested (ptid_t ptid
)
3291 struct thread_info
*tp
;
3293 /* PTID was requested to stop. If the thread was already stopped,
3294 but the user/frontend doesn't know about that yet (e.g., the
3295 thread had been temporarily paused for some step-over), set up
3296 for reporting the stop now. */
3297 ALL_NON_EXITED_THREADS (tp
)
3298 if (ptid_match (tp
->ptid
, ptid
))
3300 if (tp
->state
!= THREAD_RUNNING
)
3305 /* Remove matching threads from the step-over queue, so
3306 start_step_over doesn't try to resume them
3308 if (thread_is_in_step_over_chain (tp
))
3309 thread_step_over_chain_remove (tp
);
3311 /* If the thread is stopped, but the user/frontend doesn't
3312 know about that yet, queue a pending event, as if the
3313 thread had just stopped now. Unless the thread already had
3315 if (!tp
->suspend
.waitstatus_pending_p
)
3317 tp
->suspend
.waitstatus_pending_p
= 1;
3318 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_STOPPED
;
3319 tp
->suspend
.waitstatus
.value
.sig
= GDB_SIGNAL_0
;
3322 /* Clear the inline-frame state, since we're re-processing the
3324 clear_inline_frame_state (tp
->ptid
);
3326 /* If this thread was paused because some other thread was
3327 doing an inline-step over, let that finish first. Once
3328 that happens, we'll restart all threads and consume pending
3329 stop events then. */
3330 if (step_over_info_valid_p ())
3333 /* Otherwise we can process the (new) pending event now. Set
3334 it so this pending event is considered by
3341 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3343 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3344 nullify_last_target_wait_ptid ();
3347 /* Delete the step resume, single-step and longjmp/exception resume
3348 breakpoints of TP. */
3351 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3353 delete_step_resume_breakpoint (tp
);
3354 delete_exception_resume_breakpoint (tp
);
3355 delete_single_step_breakpoints (tp
);
3358 /* If the target still has execution, call FUNC for each thread that
3359 just stopped. In all-stop, that's all the non-exited threads; in
3360 non-stop, that's the current thread, only. */
3362 typedef void (*for_each_just_stopped_thread_callback_func
)
3363 (struct thread_info
*tp
);
3366 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3368 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3371 if (target_is_non_stop_p ())
3373 /* If in non-stop mode, only the current thread stopped. */
3374 func (inferior_thread ());
3378 struct thread_info
*tp
;
3380 /* In all-stop mode, all threads have stopped. */
3381 ALL_NON_EXITED_THREADS (tp
)
3388 /* Delete the step resume and longjmp/exception resume breakpoints of
3389 the threads that just stopped. */
3392 delete_just_stopped_threads_infrun_breakpoints (void)
3394 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3397 /* Delete the single-step breakpoints of the threads that just
3401 delete_just_stopped_threads_single_step_breakpoints (void)
3403 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3406 /* A cleanup wrapper. */
3409 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3411 delete_just_stopped_threads_infrun_breakpoints ();
3417 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3418 const struct target_waitstatus
*ws
)
3420 char *status_string
= target_waitstatus_to_string (ws
);
3423 /* The text is split over several lines because it was getting too long.
3424 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3425 output as a unit; we want only one timestamp printed if debug_timestamp
3428 stb
.printf ("infrun: target_wait (%d.%ld.%ld",
3429 ptid_get_pid (waiton_ptid
),
3430 ptid_get_lwp (waiton_ptid
),
3431 ptid_get_tid (waiton_ptid
));
3432 if (ptid_get_pid (waiton_ptid
) != -1)
3433 stb
.printf (" [%s]", target_pid_to_str (waiton_ptid
));
3434 stb
.printf (", status) =\n");
3435 stb
.printf ("infrun: %d.%ld.%ld [%s],\n",
3436 ptid_get_pid (result_ptid
),
3437 ptid_get_lwp (result_ptid
),
3438 ptid_get_tid (result_ptid
),
3439 target_pid_to_str (result_ptid
));
3440 stb
.printf ("infrun: %s\n", status_string
);
3442 /* This uses %s in part to handle %'s in the text, but also to avoid
3443 a gcc error: the format attribute requires a string literal. */
3444 fprintf_unfiltered (gdb_stdlog
, "%s", stb
.c_str ());
3446 xfree (status_string
);
3449 /* Select a thread at random, out of those which are resumed and have
3452 static struct thread_info
*
3453 random_pending_event_thread (ptid_t waiton_ptid
)
3455 struct thread_info
*event_tp
;
3457 int random_selector
;
3459 /* First see how many events we have. Count only resumed threads
3460 that have an event pending. */
3461 ALL_NON_EXITED_THREADS (event_tp
)
3462 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3463 && event_tp
->resumed
3464 && event_tp
->suspend
.waitstatus_pending_p
)
3467 if (num_events
== 0)
3470 /* Now randomly pick a thread out of those that have had events. */
3471 random_selector
= (int)
3472 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3474 if (debug_infrun
&& num_events
> 1)
3475 fprintf_unfiltered (gdb_stdlog
,
3476 "infrun: Found %d events, selecting #%d\n",
3477 num_events
, random_selector
);
3479 /* Select the Nth thread that has had an event. */
3480 ALL_NON_EXITED_THREADS (event_tp
)
3481 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3482 && event_tp
->resumed
3483 && event_tp
->suspend
.waitstatus_pending_p
)
3484 if (random_selector
-- == 0)
3490 /* Wrapper for target_wait that first checks whether threads have
3491 pending statuses to report before actually asking the target for
3495 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3498 struct thread_info
*tp
;
3500 /* First check if there is a resumed thread with a wait status
3502 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3504 tp
= random_pending_event_thread (ptid
);
3509 fprintf_unfiltered (gdb_stdlog
,
3510 "infrun: Waiting for specific thread %s.\n",
3511 target_pid_to_str (ptid
));
3513 /* We have a specific thread to check. */
3514 tp
= find_thread_ptid (ptid
);
3515 gdb_assert (tp
!= NULL
);
3516 if (!tp
->suspend
.waitstatus_pending_p
)
3521 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3522 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3524 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3525 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3529 pc
= regcache_read_pc (regcache
);
3531 if (pc
!= tp
->suspend
.stop_pc
)
3534 fprintf_unfiltered (gdb_stdlog
,
3535 "infrun: PC of %s changed. was=%s, now=%s\n",
3536 target_pid_to_str (tp
->ptid
),
3537 paddress (gdbarch
, tp
->prev_pc
),
3538 paddress (gdbarch
, pc
));
3541 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3544 fprintf_unfiltered (gdb_stdlog
,
3545 "infrun: previous breakpoint of %s, at %s gone\n",
3546 target_pid_to_str (tp
->ptid
),
3547 paddress (gdbarch
, pc
));
3555 fprintf_unfiltered (gdb_stdlog
,
3556 "infrun: pending event of %s cancelled.\n",
3557 target_pid_to_str (tp
->ptid
));
3559 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3560 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3570 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3571 fprintf_unfiltered (gdb_stdlog
,
3572 "infrun: Using pending wait status %s for %s.\n",
3574 target_pid_to_str (tp
->ptid
));
3578 /* Now that we've selected our final event LWP, un-adjust its PC
3579 if it was a software breakpoint (and the target doesn't
3580 always adjust the PC itself). */
3581 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3582 && !target_supports_stopped_by_sw_breakpoint ())
3584 struct regcache
*regcache
;
3585 struct gdbarch
*gdbarch
;
3588 regcache
= get_thread_regcache (tp
->ptid
);
3589 gdbarch
= get_regcache_arch (regcache
);
3591 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3596 pc
= regcache_read_pc (regcache
);
3597 regcache_write_pc (regcache
, pc
+ decr_pc
);
3601 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3602 *status
= tp
->suspend
.waitstatus
;
3603 tp
->suspend
.waitstatus_pending_p
= 0;
3605 /* Wake up the event loop again, until all pending events are
3607 if (target_is_async_p ())
3608 mark_async_event_handler (infrun_async_inferior_event_token
);
3612 /* But if we don't find one, we'll have to wait. */
3614 if (deprecated_target_wait_hook
)
3615 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3617 event_ptid
= target_wait (ptid
, status
, options
);
3622 /* Prepare and stabilize the inferior for detaching it. E.g.,
3623 detaching while a thread is displaced stepping is a recipe for
3624 crashing it, as nothing would readjust the PC out of the scratch
3628 prepare_for_detach (void)
3630 struct inferior
*inf
= current_inferior ();
3631 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3632 struct cleanup
*old_chain_1
;
3633 struct displaced_step_inferior_state
*displaced
;
3635 displaced
= get_displaced_stepping_state (inf
->pid
);
3637 /* Is any thread of this process displaced stepping? If not,
3638 there's nothing else to do. */
3639 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3643 fprintf_unfiltered (gdb_stdlog
,
3644 "displaced-stepping in-process while detaching");
3646 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3649 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3651 struct cleanup
*old_chain_2
;
3652 struct execution_control_state ecss
;
3653 struct execution_control_state
*ecs
;
3656 memset (ecs
, 0, sizeof (*ecs
));
3658 overlay_cache_invalid
= 1;
3659 /* Flush target cache before starting to handle each event.
3660 Target was running and cache could be stale. This is just a
3661 heuristic. Running threads may modify target memory, but we
3662 don't get any event. */
3663 target_dcache_invalidate ();
3665 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3668 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3670 /* If an error happens while handling the event, propagate GDB's
3671 knowledge of the executing state to the frontend/user running
3673 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3676 /* Now figure out what to do with the result of the result. */
3677 handle_inferior_event (ecs
);
3679 /* No error, don't finish the state yet. */
3680 discard_cleanups (old_chain_2
);
3682 /* Breakpoints and watchpoints are not installed on the target
3683 at this point, and signals are passed directly to the
3684 inferior, so this must mean the process is gone. */
3685 if (!ecs
->wait_some_more
)
3687 discard_cleanups (old_chain_1
);
3688 error (_("Program exited while detaching"));
3692 discard_cleanups (old_chain_1
);
3695 /* Wait for control to return from inferior to debugger.
3697 If inferior gets a signal, we may decide to start it up again
3698 instead of returning. That is why there is a loop in this function.
3699 When this function actually returns it means the inferior
3700 should be left stopped and GDB should read more commands. */
3703 wait_for_inferior (void)
3705 struct cleanup
*old_cleanups
;
3706 struct cleanup
*thread_state_chain
;
3710 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3713 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3716 /* If an error happens while handling the event, propagate GDB's
3717 knowledge of the executing state to the frontend/user running
3719 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3723 struct execution_control_state ecss
;
3724 struct execution_control_state
*ecs
= &ecss
;
3725 ptid_t waiton_ptid
= minus_one_ptid
;
3727 memset (ecs
, 0, sizeof (*ecs
));
3729 overlay_cache_invalid
= 1;
3731 /* Flush target cache before starting to handle each event.
3732 Target was running and cache could be stale. This is just a
3733 heuristic. Running threads may modify target memory, but we
3734 don't get any event. */
3735 target_dcache_invalidate ();
3737 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3740 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3742 /* Now figure out what to do with the result of the result. */
3743 handle_inferior_event (ecs
);
3745 if (!ecs
->wait_some_more
)
3749 /* No error, don't finish the state yet. */
3750 discard_cleanups (thread_state_chain
);
3752 do_cleanups (old_cleanups
);
3755 /* Cleanup that reinstalls the readline callback handler, if the
3756 target is running in the background. If while handling the target
3757 event something triggered a secondary prompt, like e.g., a
3758 pagination prompt, we'll have removed the callback handler (see
3759 gdb_readline_wrapper_line). Need to do this as we go back to the
3760 event loop, ready to process further input. Note this has no
3761 effect if the handler hasn't actually been removed, because calling
3762 rl_callback_handler_install resets the line buffer, thus losing
3766 reinstall_readline_callback_handler_cleanup (void *arg
)
3768 struct ui
*ui
= current_ui
;
3772 /* We're not going back to the top level event loop yet. Don't
3773 install the readline callback, as it'd prep the terminal,
3774 readline-style (raw, noecho) (e.g., --batch). We'll install
3775 it the next time the prompt is displayed, when we're ready
3780 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3781 gdb_rl_callback_handler_reinstall ();
3784 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3785 that's just the event thread. In all-stop, that's all threads. */
3788 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3790 struct thread_info
*thr
= ecs
->event_thread
;
3792 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3793 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3797 ALL_NON_EXITED_THREADS (thr
)
3799 if (thr
->thread_fsm
== NULL
)
3801 if (thr
== ecs
->event_thread
)
3804 switch_to_thread (thr
->ptid
);
3805 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3808 if (ecs
->event_thread
!= NULL
)
3809 switch_to_thread (ecs
->event_thread
->ptid
);
3813 /* Helper for all_uis_check_sync_execution_done that works on the
3817 check_curr_ui_sync_execution_done (void)
3819 struct ui
*ui
= current_ui
;
3821 if (ui
->prompt_state
== PROMPT_NEEDED
3823 && !gdb_in_secondary_prompt_p (ui
))
3825 target_terminal_ours ();
3826 observer_notify_sync_execution_done ();
3827 ui_register_input_event_handler (ui
);
3834 all_uis_check_sync_execution_done (void)
3836 SWITCH_THRU_ALL_UIS ()
3838 check_curr_ui_sync_execution_done ();
3845 all_uis_on_sync_execution_starting (void)
3847 SWITCH_THRU_ALL_UIS ()
3849 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3850 async_disable_stdin ();
3854 /* Asynchronous version of wait_for_inferior. It is called by the
3855 event loop whenever a change of state is detected on the file
3856 descriptor corresponding to the target. It can be called more than
3857 once to complete a single execution command. In such cases we need
3858 to keep the state in a global variable ECSS. If it is the last time
3859 that this function is called for a single execution command, then
3860 report to the user that the inferior has stopped, and do the
3861 necessary cleanups. */
3864 fetch_inferior_event (void *client_data
)
3866 struct execution_control_state ecss
;
3867 struct execution_control_state
*ecs
= &ecss
;
3868 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3869 struct cleanup
*ts_old_chain
;
3871 ptid_t waiton_ptid
= minus_one_ptid
;
3873 memset (ecs
, 0, sizeof (*ecs
));
3875 /* Events are always processed with the main UI as current UI. This
3876 way, warnings, debug output, etc. are always consistently sent to
3877 the main console. */
3878 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3880 /* End up with readline processing input, if necessary. */
3881 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3883 /* We're handling a live event, so make sure we're doing live
3884 debugging. If we're looking at traceframes while the target is
3885 running, we're going to need to get back to that mode after
3886 handling the event. */
3889 make_cleanup_restore_current_traceframe ();
3890 set_current_traceframe (-1);
3894 /* In non-stop mode, the user/frontend should not notice a thread
3895 switch due to internal events. Make sure we reverse to the
3896 user selected thread and frame after handling the event and
3897 running any breakpoint commands. */
3898 make_cleanup_restore_current_thread ();
3900 overlay_cache_invalid
= 1;
3901 /* Flush target cache before starting to handle each event. Target
3902 was running and cache could be stale. This is just a heuristic.
3903 Running threads may modify target memory, but we don't get any
3905 target_dcache_invalidate ();
3907 scoped_restore save_exec_dir
3908 = make_scoped_restore (&execution_direction
, target_execution_direction ());
3910 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3911 target_can_async_p () ? TARGET_WNOHANG
: 0);
3914 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3916 /* If an error happens while handling the event, propagate GDB's
3917 knowledge of the executing state to the frontend/user running
3919 if (!target_is_non_stop_p ())
3920 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3922 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3924 /* Get executed before make_cleanup_restore_current_thread above to apply
3925 still for the thread which has thrown the exception. */
3926 make_bpstat_clear_actions_cleanup ();
3928 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3930 /* Now figure out what to do with the result of the result. */
3931 handle_inferior_event (ecs
);
3933 if (!ecs
->wait_some_more
)
3935 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3936 int should_stop
= 1;
3937 struct thread_info
*thr
= ecs
->event_thread
;
3938 int should_notify_stop
= 1;
3940 delete_just_stopped_threads_infrun_breakpoints ();
3944 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3946 if (thread_fsm
!= NULL
)
3947 should_stop
= thread_fsm_should_stop (thread_fsm
, thr
);
3956 clean_up_just_stopped_threads_fsms (ecs
);
3958 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3961 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
3964 if (should_notify_stop
)
3968 /* We may not find an inferior if this was a process exit. */
3969 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3970 proceeded
= normal_stop ();
3974 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3981 /* No error, don't finish the thread states yet. */
3982 discard_cleanups (ts_old_chain
);
3984 /* Revert thread and frame. */
3985 do_cleanups (old_chain
);
3987 /* If a UI was in sync execution mode, and now isn't, restore its
3988 prompt (a synchronous execution command has finished, and we're
3989 ready for input). */
3990 all_uis_check_sync_execution_done ();
3993 && exec_done_display_p
3994 && (ptid_equal (inferior_ptid
, null_ptid
)
3995 || !is_running (inferior_ptid
)))
3996 printf_unfiltered (_("completed.\n"));
3999 /* Record the frame and location we're currently stepping through. */
4001 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
4003 struct thread_info
*tp
= inferior_thread ();
4005 tp
->control
.step_frame_id
= get_frame_id (frame
);
4006 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4008 tp
->current_symtab
= sal
.symtab
;
4009 tp
->current_line
= sal
.line
;
4012 /* Clear context switchable stepping state. */
4015 init_thread_stepping_state (struct thread_info
*tss
)
4017 tss
->stepped_breakpoint
= 0;
4018 tss
->stepping_over_breakpoint
= 0;
4019 tss
->stepping_over_watchpoint
= 0;
4020 tss
->step_after_step_resume_breakpoint
= 0;
4023 /* Set the cached copy of the last ptid/waitstatus. */
4026 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
4028 target_last_wait_ptid
= ptid
;
4029 target_last_waitstatus
= status
;
4032 /* Return the cached copy of the last pid/waitstatus returned by
4033 target_wait()/deprecated_target_wait_hook(). The data is actually
4034 cached by handle_inferior_event(), which gets called immediately
4035 after target_wait()/deprecated_target_wait_hook(). */
4038 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
4040 *ptidp
= target_last_wait_ptid
;
4041 *status
= target_last_waitstatus
;
4045 nullify_last_target_wait_ptid (void)
4047 target_last_wait_ptid
= minus_one_ptid
;
4050 /* Switch thread contexts. */
4053 context_switch (ptid_t ptid
)
4055 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4057 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4058 target_pid_to_str (inferior_ptid
));
4059 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4060 target_pid_to_str (ptid
));
4063 switch_to_thread (ptid
);
4066 /* If the target can't tell whether we've hit breakpoints
4067 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4068 check whether that could have been caused by a breakpoint. If so,
4069 adjust the PC, per gdbarch_decr_pc_after_break. */
4072 adjust_pc_after_break (struct thread_info
*thread
,
4073 struct target_waitstatus
*ws
)
4075 struct regcache
*regcache
;
4076 struct gdbarch
*gdbarch
;
4077 struct address_space
*aspace
;
4078 CORE_ADDR breakpoint_pc
, decr_pc
;
4080 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4081 we aren't, just return.
4083 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4084 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4085 implemented by software breakpoints should be handled through the normal
4088 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4089 different signals (SIGILL or SIGEMT for instance), but it is less
4090 clear where the PC is pointing afterwards. It may not match
4091 gdbarch_decr_pc_after_break. I don't know any specific target that
4092 generates these signals at breakpoints (the code has been in GDB since at
4093 least 1992) so I can not guess how to handle them here.
4095 In earlier versions of GDB, a target with
4096 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4097 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4098 target with both of these set in GDB history, and it seems unlikely to be
4099 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4101 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4104 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4107 /* In reverse execution, when a breakpoint is hit, the instruction
4108 under it has already been de-executed. The reported PC always
4109 points at the breakpoint address, so adjusting it further would
4110 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4113 B1 0x08000000 : INSN1
4114 B2 0x08000001 : INSN2
4116 PC -> 0x08000003 : INSN4
4118 Say you're stopped at 0x08000003 as above. Reverse continuing
4119 from that point should hit B2 as below. Reading the PC when the
4120 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4121 been de-executed already.
4123 B1 0x08000000 : INSN1
4124 B2 PC -> 0x08000001 : INSN2
4128 We can't apply the same logic as for forward execution, because
4129 we would wrongly adjust the PC to 0x08000000, since there's a
4130 breakpoint at PC - 1. We'd then report a hit on B1, although
4131 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4133 if (execution_direction
== EXEC_REVERSE
)
4136 /* If the target can tell whether the thread hit a SW breakpoint,
4137 trust it. Targets that can tell also adjust the PC
4139 if (target_supports_stopped_by_sw_breakpoint ())
4142 /* Note that relying on whether a breakpoint is planted in memory to
4143 determine this can fail. E.g,. the breakpoint could have been
4144 removed since. Or the thread could have been told to step an
4145 instruction the size of a breakpoint instruction, and only
4146 _after_ was a breakpoint inserted at its address. */
4148 /* If this target does not decrement the PC after breakpoints, then
4149 we have nothing to do. */
4150 regcache
= get_thread_regcache (thread
->ptid
);
4151 gdbarch
= get_regcache_arch (regcache
);
4153 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4157 aspace
= get_regcache_aspace (regcache
);
4159 /* Find the location where (if we've hit a breakpoint) the
4160 breakpoint would be. */
4161 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4163 /* If the target can't tell whether a software breakpoint triggered,
4164 fallback to figuring it out based on breakpoints we think were
4165 inserted in the target, and on whether the thread was stepped or
4168 /* Check whether there actually is a software breakpoint inserted at
4171 If in non-stop mode, a race condition is possible where we've
4172 removed a breakpoint, but stop events for that breakpoint were
4173 already queued and arrive later. To suppress those spurious
4174 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4175 and retire them after a number of stop events are reported. Note
4176 this is an heuristic and can thus get confused. The real fix is
4177 to get the "stopped by SW BP and needs adjustment" info out of
4178 the target/kernel (and thus never reach here; see above). */
4179 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4180 || (target_is_non_stop_p ()
4181 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4183 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4185 if (record_full_is_used ())
4186 record_full_gdb_operation_disable_set ();
4188 /* When using hardware single-step, a SIGTRAP is reported for both
4189 a completed single-step and a software breakpoint. Need to
4190 differentiate between the two, as the latter needs adjusting
4191 but the former does not.
4193 The SIGTRAP can be due to a completed hardware single-step only if
4194 - we didn't insert software single-step breakpoints
4195 - this thread is currently being stepped
4197 If any of these events did not occur, we must have stopped due
4198 to hitting a software breakpoint, and have to back up to the
4201 As a special case, we could have hardware single-stepped a
4202 software breakpoint. In this case (prev_pc == breakpoint_pc),
4203 we also need to back up to the breakpoint address. */
4205 if (thread_has_single_step_breakpoints_set (thread
)
4206 || !currently_stepping (thread
)
4207 || (thread
->stepped_breakpoint
4208 && thread
->prev_pc
== breakpoint_pc
))
4209 regcache_write_pc (regcache
, breakpoint_pc
);
4211 do_cleanups (old_cleanups
);
4216 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4218 for (frame
= get_prev_frame (frame
);
4220 frame
= get_prev_frame (frame
))
4222 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4224 if (get_frame_type (frame
) != INLINE_FRAME
)
4231 /* If the event thread has the stop requested flag set, pretend it
4232 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4236 handle_stop_requested (struct execution_control_state
*ecs
)
4238 if (ecs
->event_thread
->stop_requested
)
4240 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4241 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4242 handle_signal_stop (ecs
);
4248 /* Auxiliary function that handles syscall entry/return events.
4249 It returns 1 if the inferior should keep going (and GDB
4250 should ignore the event), or 0 if the event deserves to be
4254 handle_syscall_event (struct execution_control_state
*ecs
)
4256 struct regcache
*regcache
;
4259 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4260 context_switch (ecs
->ptid
);
4262 regcache
= get_thread_regcache (ecs
->ptid
);
4263 syscall_number
= ecs
->ws
.value
.syscall_number
;
4264 stop_pc
= regcache_read_pc (regcache
);
4266 if (catch_syscall_enabled () > 0
4267 && catching_syscall_number (syscall_number
) > 0)
4270 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4273 ecs
->event_thread
->control
.stop_bpstat
4274 = bpstat_stop_status (get_regcache_aspace (regcache
),
4275 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4277 if (handle_stop_requested (ecs
))
4280 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4282 /* Catchpoint hit. */
4287 if (handle_stop_requested (ecs
))
4290 /* If no catchpoint triggered for this, then keep going. */
4295 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4298 fill_in_stop_func (struct gdbarch
*gdbarch
,
4299 struct execution_control_state
*ecs
)
4301 if (!ecs
->stop_func_filled_in
)
4303 /* Don't care about return value; stop_func_start and stop_func_name
4304 will both be 0 if it doesn't work. */
4305 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4306 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4307 ecs
->stop_func_start
4308 += gdbarch_deprecated_function_start_offset (gdbarch
);
4310 if (gdbarch_skip_entrypoint_p (gdbarch
))
4311 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4312 ecs
->stop_func_start
);
4314 ecs
->stop_func_filled_in
= 1;
4319 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4321 static enum stop_kind
4322 get_inferior_stop_soon (ptid_t ptid
)
4324 struct inferior
*inf
= find_inferior_ptid (ptid
);
4326 gdb_assert (inf
!= NULL
);
4327 return inf
->control
.stop_soon
;
4330 /* Wait for one event. Store the resulting waitstatus in WS, and
4331 return the event ptid. */
4334 wait_one (struct target_waitstatus
*ws
)
4337 ptid_t wait_ptid
= minus_one_ptid
;
4339 overlay_cache_invalid
= 1;
4341 /* Flush target cache before starting to handle each event.
4342 Target was running and cache could be stale. This is just a
4343 heuristic. Running threads may modify target memory, but we
4344 don't get any event. */
4345 target_dcache_invalidate ();
4347 if (deprecated_target_wait_hook
)
4348 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4350 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4353 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4358 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4359 instead of the current thread. */
4360 #define THREAD_STOPPED_BY(REASON) \
4362 thread_stopped_by_ ## REASON (ptid_t ptid) \
4364 struct cleanup *old_chain; \
4367 old_chain = save_inferior_ptid (); \
4368 inferior_ptid = ptid; \
4370 res = target_stopped_by_ ## REASON (); \
4372 do_cleanups (old_chain); \
4377 /* Generate thread_stopped_by_watchpoint. */
4378 THREAD_STOPPED_BY (watchpoint
)
4379 /* Generate thread_stopped_by_sw_breakpoint. */
4380 THREAD_STOPPED_BY (sw_breakpoint
)
4381 /* Generate thread_stopped_by_hw_breakpoint. */
4382 THREAD_STOPPED_BY (hw_breakpoint
)
4384 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4387 switch_to_thread_cleanup (void *ptid_p
)
4389 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4391 switch_to_thread (ptid
);
4394 /* Save the thread's event and stop reason to process it later. */
4397 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4399 struct regcache
*regcache
;
4400 struct address_space
*aspace
;
4406 statstr
= target_waitstatus_to_string (ws
);
4407 fprintf_unfiltered (gdb_stdlog
,
4408 "infrun: saving status %s for %d.%ld.%ld\n",
4410 ptid_get_pid (tp
->ptid
),
4411 ptid_get_lwp (tp
->ptid
),
4412 ptid_get_tid (tp
->ptid
));
4416 /* Record for later. */
4417 tp
->suspend
.waitstatus
= *ws
;
4418 tp
->suspend
.waitstatus_pending_p
= 1;
4420 regcache
= get_thread_regcache (tp
->ptid
);
4421 aspace
= get_regcache_aspace (regcache
);
4423 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4424 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4426 CORE_ADDR pc
= regcache_read_pc (regcache
);
4428 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4430 if (thread_stopped_by_watchpoint (tp
->ptid
))
4432 tp
->suspend
.stop_reason
4433 = TARGET_STOPPED_BY_WATCHPOINT
;
4435 else if (target_supports_stopped_by_sw_breakpoint ()
4436 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4438 tp
->suspend
.stop_reason
4439 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4441 else if (target_supports_stopped_by_hw_breakpoint ()
4442 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4444 tp
->suspend
.stop_reason
4445 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4447 else if (!target_supports_stopped_by_hw_breakpoint ()
4448 && hardware_breakpoint_inserted_here_p (aspace
,
4451 tp
->suspend
.stop_reason
4452 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4454 else if (!target_supports_stopped_by_sw_breakpoint ()
4455 && software_breakpoint_inserted_here_p (aspace
,
4458 tp
->suspend
.stop_reason
4459 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4461 else if (!thread_has_single_step_breakpoints_set (tp
)
4462 && currently_stepping (tp
))
4464 tp
->suspend
.stop_reason
4465 = TARGET_STOPPED_BY_SINGLE_STEP
;
4470 /* A cleanup that disables thread create/exit events. */
4473 disable_thread_events (void *arg
)
4475 target_thread_events (0);
4481 stop_all_threads (void)
4483 /* We may need multiple passes to discover all threads. */
4487 struct cleanup
*old_chain
;
4489 gdb_assert (target_is_non_stop_p ());
4492 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4494 entry_ptid
= inferior_ptid
;
4495 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4497 target_thread_events (1);
4498 make_cleanup (disable_thread_events
, NULL
);
4500 /* Request threads to stop, and then wait for the stops. Because
4501 threads we already know about can spawn more threads while we're
4502 trying to stop them, and we only learn about new threads when we
4503 update the thread list, do this in a loop, and keep iterating
4504 until two passes find no threads that need to be stopped. */
4505 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4508 fprintf_unfiltered (gdb_stdlog
,
4509 "infrun: stop_all_threads, pass=%d, "
4510 "iterations=%d\n", pass
, iterations
);
4514 struct target_waitstatus ws
;
4516 struct thread_info
*t
;
4518 update_thread_list ();
4520 /* Go through all threads looking for threads that we need
4521 to tell the target to stop. */
4522 ALL_NON_EXITED_THREADS (t
)
4526 /* If already stopping, don't request a stop again.
4527 We just haven't seen the notification yet. */
4528 if (!t
->stop_requested
)
4531 fprintf_unfiltered (gdb_stdlog
,
4532 "infrun: %s executing, "
4534 target_pid_to_str (t
->ptid
));
4535 target_stop (t
->ptid
);
4536 t
->stop_requested
= 1;
4541 fprintf_unfiltered (gdb_stdlog
,
4542 "infrun: %s executing, "
4543 "already stopping\n",
4544 target_pid_to_str (t
->ptid
));
4547 if (t
->stop_requested
)
4553 fprintf_unfiltered (gdb_stdlog
,
4554 "infrun: %s not executing\n",
4555 target_pid_to_str (t
->ptid
));
4557 /* The thread may be not executing, but still be
4558 resumed with a pending status to process. */
4566 /* If we find new threads on the second iteration, restart
4567 over. We want to see two iterations in a row with all
4572 event_ptid
= wait_one (&ws
);
4573 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4575 /* All resumed threads exited. */
4577 else if (ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4578 || ws
.kind
== TARGET_WAITKIND_EXITED
4579 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4583 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4585 fprintf_unfiltered (gdb_stdlog
,
4586 "infrun: %s exited while "
4587 "stopping threads\n",
4588 target_pid_to_str (ptid
));
4593 struct inferior
*inf
;
4595 t
= find_thread_ptid (event_ptid
);
4597 t
= add_thread (event_ptid
);
4599 t
->stop_requested
= 0;
4602 t
->control
.may_range_step
= 0;
4604 /* This may be the first time we see the inferior report
4606 inf
= find_inferior_ptid (event_ptid
);
4607 if (inf
->needs_setup
)
4609 switch_to_thread_no_regs (t
);
4613 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4614 && ws
.value
.sig
== GDB_SIGNAL_0
)
4616 /* We caught the event that we intended to catch, so
4617 there's no event pending. */
4618 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4619 t
->suspend
.waitstatus_pending_p
= 0;
4621 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4623 /* Add it back to the step-over queue. */
4626 fprintf_unfiltered (gdb_stdlog
,
4627 "infrun: displaced-step of %s "
4628 "canceled: adding back to the "
4629 "step-over queue\n",
4630 target_pid_to_str (t
->ptid
));
4632 t
->control
.trap_expected
= 0;
4633 thread_step_over_chain_enqueue (t
);
4638 enum gdb_signal sig
;
4639 struct regcache
*regcache
;
4645 statstr
= target_waitstatus_to_string (&ws
);
4646 fprintf_unfiltered (gdb_stdlog
,
4647 "infrun: target_wait %s, saving "
4648 "status for %d.%ld.%ld\n",
4650 ptid_get_pid (t
->ptid
),
4651 ptid_get_lwp (t
->ptid
),
4652 ptid_get_tid (t
->ptid
));
4656 /* Record for later. */
4657 save_waitstatus (t
, &ws
);
4659 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4660 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4662 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4664 /* Add it back to the step-over queue. */
4665 t
->control
.trap_expected
= 0;
4666 thread_step_over_chain_enqueue (t
);
4669 regcache
= get_thread_regcache (t
->ptid
);
4670 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4674 fprintf_unfiltered (gdb_stdlog
,
4675 "infrun: saved stop_pc=%s for %s "
4676 "(currently_stepping=%d)\n",
4677 paddress (target_gdbarch (),
4678 t
->suspend
.stop_pc
),
4679 target_pid_to_str (t
->ptid
),
4680 currently_stepping (t
));
4687 do_cleanups (old_chain
);
4690 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4693 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4696 handle_no_resumed (struct execution_control_state
*ecs
)
4698 struct inferior
*inf
;
4699 struct thread_info
*thread
;
4701 if (target_can_async_p ())
4708 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4716 /* There were no unwaited-for children left in the target, but,
4717 we're not synchronously waiting for events either. Just
4721 fprintf_unfiltered (gdb_stdlog
,
4722 "infrun: TARGET_WAITKIND_NO_RESUMED "
4723 "(ignoring: bg)\n");
4724 prepare_to_wait (ecs
);
4729 /* Otherwise, if we were running a synchronous execution command, we
4730 may need to cancel it and give the user back the terminal.
4732 In non-stop mode, the target can't tell whether we've already
4733 consumed previous stop events, so it can end up sending us a
4734 no-resumed event like so:
4736 #0 - thread 1 is left stopped
4738 #1 - thread 2 is resumed and hits breakpoint
4739 -> TARGET_WAITKIND_STOPPED
4741 #2 - thread 3 is resumed and exits
4742 this is the last resumed thread, so
4743 -> TARGET_WAITKIND_NO_RESUMED
4745 #3 - gdb processes stop for thread 2 and decides to re-resume
4748 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4749 thread 2 is now resumed, so the event should be ignored.
4751 IOW, if the stop for thread 2 doesn't end a foreground command,
4752 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4753 event. But it could be that the event meant that thread 2 itself
4754 (or whatever other thread was the last resumed thread) exited.
4756 To address this we refresh the thread list and check whether we
4757 have resumed threads _now_. In the example above, this removes
4758 thread 3 from the thread list. If thread 2 was re-resumed, we
4759 ignore this event. If we find no thread resumed, then we cancel
4760 the synchronous command show "no unwaited-for " to the user. */
4761 update_thread_list ();
4763 ALL_NON_EXITED_THREADS (thread
)
4765 if (thread
->executing
4766 || thread
->suspend
.waitstatus_pending_p
)
4768 /* There were no unwaited-for children left in the target at
4769 some point, but there are now. Just ignore. */
4771 fprintf_unfiltered (gdb_stdlog
,
4772 "infrun: TARGET_WAITKIND_NO_RESUMED "
4773 "(ignoring: found resumed)\n");
4774 prepare_to_wait (ecs
);
4779 /* Note however that we may find no resumed thread because the whole
4780 process exited meanwhile (thus updating the thread list results
4781 in an empty thread list). In this case we know we'll be getting
4782 a process exit event shortly. */
4788 thread
= any_live_thread_of_process (inf
->pid
);
4792 fprintf_unfiltered (gdb_stdlog
,
4793 "infrun: TARGET_WAITKIND_NO_RESUMED "
4794 "(expect process exit)\n");
4795 prepare_to_wait (ecs
);
4800 /* Go ahead and report the event. */
4804 /* Given an execution control state that has been freshly filled in by
4805 an event from the inferior, figure out what it means and take
4808 The alternatives are:
4810 1) stop_waiting and return; to really stop and return to the
4813 2) keep_going and return; to wait for the next event (set
4814 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4818 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4820 enum stop_kind stop_soon
;
4822 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4824 /* We had an event in the inferior, but we are not interested in
4825 handling it at this level. The lower layers have already
4826 done what needs to be done, if anything.
4828 One of the possible circumstances for this is when the
4829 inferior produces output for the console. The inferior has
4830 not stopped, and we are ignoring the event. Another possible
4831 circumstance is any event which the lower level knows will be
4832 reported multiple times without an intervening resume. */
4834 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4835 prepare_to_wait (ecs
);
4839 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4842 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4843 prepare_to_wait (ecs
);
4847 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4848 && handle_no_resumed (ecs
))
4851 /* Cache the last pid/waitstatus. */
4852 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4854 /* Always clear state belonging to the previous time we stopped. */
4855 stop_stack_dummy
= STOP_NONE
;
4857 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4859 /* No unwaited-for children left. IOW, all resumed children
4862 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4864 stop_print_frame
= 0;
4869 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4870 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4872 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4873 /* If it's a new thread, add it to the thread database. */
4874 if (ecs
->event_thread
== NULL
)
4875 ecs
->event_thread
= add_thread (ecs
->ptid
);
4877 /* Disable range stepping. If the next step request could use a
4878 range, this will be end up re-enabled then. */
4879 ecs
->event_thread
->control
.may_range_step
= 0;
4882 /* Dependent on valid ECS->EVENT_THREAD. */
4883 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4885 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4886 reinit_frame_cache ();
4888 breakpoint_retire_moribund ();
4890 /* First, distinguish signals caused by the debugger from signals
4891 that have to do with the program's own actions. Note that
4892 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4893 on the operating system version. Here we detect when a SIGILL or
4894 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4895 something similar for SIGSEGV, since a SIGSEGV will be generated
4896 when we're trying to execute a breakpoint instruction on a
4897 non-executable stack. This happens for call dummy breakpoints
4898 for architectures like SPARC that place call dummies on the
4900 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4901 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4902 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4903 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4905 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4907 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4908 regcache_read_pc (regcache
)))
4911 fprintf_unfiltered (gdb_stdlog
,
4912 "infrun: Treating signal as SIGTRAP\n");
4913 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4917 /* Mark the non-executing threads accordingly. In all-stop, all
4918 threads of all processes are stopped when we get any event
4919 reported. In non-stop mode, only the event thread stops. */
4923 if (!target_is_non_stop_p ())
4924 mark_ptid
= minus_one_ptid
;
4925 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4926 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4928 /* If we're handling a process exit in non-stop mode, even
4929 though threads haven't been deleted yet, one would think
4930 that there is nothing to do, as threads of the dead process
4931 will be soon deleted, and threads of any other process were
4932 left running. However, on some targets, threads survive a
4933 process exit event. E.g., for the "checkpoint" command,
4934 when the current checkpoint/fork exits, linux-fork.c
4935 automatically switches to another fork from within
4936 target_mourn_inferior, by associating the same
4937 inferior/thread to another fork. We haven't mourned yet at
4938 this point, but we must mark any threads left in the
4939 process as not-executing so that finish_thread_state marks
4940 them stopped (in the user's perspective) if/when we present
4941 the stop to the user. */
4942 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4945 mark_ptid
= ecs
->ptid
;
4947 set_executing (mark_ptid
, 0);
4949 /* Likewise the resumed flag. */
4950 set_resumed (mark_ptid
, 0);
4953 switch (ecs
->ws
.kind
)
4955 case TARGET_WAITKIND_LOADED
:
4957 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4958 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4959 context_switch (ecs
->ptid
);
4960 /* Ignore gracefully during startup of the inferior, as it might
4961 be the shell which has just loaded some objects, otherwise
4962 add the symbols for the newly loaded objects. Also ignore at
4963 the beginning of an attach or remote session; we will query
4964 the full list of libraries once the connection is
4967 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4968 if (stop_soon
== NO_STOP_QUIETLY
)
4970 struct regcache
*regcache
;
4972 regcache
= get_thread_regcache (ecs
->ptid
);
4974 handle_solib_event ();
4976 ecs
->event_thread
->control
.stop_bpstat
4977 = bpstat_stop_status (get_regcache_aspace (regcache
),
4978 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4980 if (handle_stop_requested (ecs
))
4983 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4985 /* A catchpoint triggered. */
4986 process_event_stop_test (ecs
);
4990 /* If requested, stop when the dynamic linker notifies
4991 gdb of events. This allows the user to get control
4992 and place breakpoints in initializer routines for
4993 dynamically loaded objects (among other things). */
4994 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4995 if (stop_on_solib_events
)
4997 /* Make sure we print "Stopped due to solib-event" in
4999 stop_print_frame
= 1;
5006 /* If we are skipping through a shell, or through shared library
5007 loading that we aren't interested in, resume the program. If
5008 we're running the program normally, also resume. */
5009 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5011 /* Loading of shared libraries might have changed breakpoint
5012 addresses. Make sure new breakpoints are inserted. */
5013 if (stop_soon
== NO_STOP_QUIETLY
)
5014 insert_breakpoints ();
5015 resume (GDB_SIGNAL_0
);
5016 prepare_to_wait (ecs
);
5020 /* But stop if we're attaching or setting up a remote
5022 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5023 || stop_soon
== STOP_QUIETLY_REMOTE
)
5026 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5031 internal_error (__FILE__
, __LINE__
,
5032 _("unhandled stop_soon: %d"), (int) stop_soon
);
5034 case TARGET_WAITKIND_SPURIOUS
:
5036 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5037 if (handle_stop_requested (ecs
))
5039 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5040 context_switch (ecs
->ptid
);
5041 resume (GDB_SIGNAL_0
);
5042 prepare_to_wait (ecs
);
5045 case TARGET_WAITKIND_THREAD_CREATED
:
5047 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5048 if (handle_stop_requested (ecs
))
5050 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5051 context_switch (ecs
->ptid
);
5052 if (!switch_back_to_stepped_thread (ecs
))
5056 case TARGET_WAITKIND_EXITED
:
5057 case TARGET_WAITKIND_SIGNALLED
:
5060 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5061 fprintf_unfiltered (gdb_stdlog
,
5062 "infrun: TARGET_WAITKIND_EXITED\n");
5064 fprintf_unfiltered (gdb_stdlog
,
5065 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5068 inferior_ptid
= ecs
->ptid
;
5069 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
5070 set_current_program_space (current_inferior ()->pspace
);
5071 handle_vfork_child_exec_or_exit (0);
5072 target_terminal_ours (); /* Must do this before mourn anyway. */
5074 /* Clearing any previous state of convenience variables. */
5075 clear_exit_convenience_vars ();
5077 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5079 /* Record the exit code in the convenience variable $_exitcode, so
5080 that the user can inspect this again later. */
5081 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5082 (LONGEST
) ecs
->ws
.value
.integer
);
5084 /* Also record this in the inferior itself. */
5085 current_inferior ()->has_exit_code
= 1;
5086 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5088 /* Support the --return-child-result option. */
5089 return_child_result_value
= ecs
->ws
.value
.integer
;
5091 observer_notify_exited (ecs
->ws
.value
.integer
);
5095 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5096 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5098 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5100 /* Set the value of the internal variable $_exitsignal,
5101 which holds the signal uncaught by the inferior. */
5102 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5103 gdbarch_gdb_signal_to_target (gdbarch
,
5104 ecs
->ws
.value
.sig
));
5108 /* We don't have access to the target's method used for
5109 converting between signal numbers (GDB's internal
5110 representation <-> target's representation).
5111 Therefore, we cannot do a good job at displaying this
5112 information to the user. It's better to just warn
5113 her about it (if infrun debugging is enabled), and
5116 fprintf_filtered (gdb_stdlog
, _("\
5117 Cannot fill $_exitsignal with the correct signal number.\n"));
5120 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
5123 gdb_flush (gdb_stdout
);
5124 target_mourn_inferior (inferior_ptid
);
5125 stop_print_frame
= 0;
5129 /* The following are the only cases in which we keep going;
5130 the above cases end in a continue or goto. */
5131 case TARGET_WAITKIND_FORKED
:
5132 case TARGET_WAITKIND_VFORKED
:
5135 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5136 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
5138 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
5141 /* Check whether the inferior is displaced stepping. */
5143 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5144 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5146 /* If checking displaced stepping is supported, and thread
5147 ecs->ptid is displaced stepping. */
5148 if (displaced_step_in_progress_thread (ecs
->ptid
))
5150 struct inferior
*parent_inf
5151 = find_inferior_ptid (ecs
->ptid
);
5152 struct regcache
*child_regcache
;
5153 CORE_ADDR parent_pc
;
5155 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5156 indicating that the displaced stepping of syscall instruction
5157 has been done. Perform cleanup for parent process here. Note
5158 that this operation also cleans up the child process for vfork,
5159 because their pages are shared. */
5160 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
5161 /* Start a new step-over in another thread if there's one
5165 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5167 struct displaced_step_inferior_state
*displaced
5168 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
5170 /* Restore scratch pad for child process. */
5171 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
5174 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5175 the child's PC is also within the scratchpad. Set the child's PC
5176 to the parent's PC value, which has already been fixed up.
5177 FIXME: we use the parent's aspace here, although we're touching
5178 the child, because the child hasn't been added to the inferior
5179 list yet at this point. */
5182 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
5184 parent_inf
->aspace
);
5185 /* Read PC value of parent process. */
5186 parent_pc
= regcache_read_pc (regcache
);
5188 if (debug_displaced
)
5189 fprintf_unfiltered (gdb_stdlog
,
5190 "displaced: write child pc from %s to %s\n",
5192 regcache_read_pc (child_regcache
)),
5193 paddress (gdbarch
, parent_pc
));
5195 regcache_write_pc (child_regcache
, parent_pc
);
5199 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5200 context_switch (ecs
->ptid
);
5202 /* Immediately detach breakpoints from the child before there's
5203 any chance of letting the user delete breakpoints from the
5204 breakpoint lists. If we don't do this early, it's easy to
5205 leave left over traps in the child, vis: "break foo; catch
5206 fork; c; <fork>; del; c; <child calls foo>". We only follow
5207 the fork on the last `continue', and by that time the
5208 breakpoint at "foo" is long gone from the breakpoint table.
5209 If we vforked, then we don't need to unpatch here, since both
5210 parent and child are sharing the same memory pages; we'll
5211 need to unpatch at follow/detach time instead to be certain
5212 that new breakpoints added between catchpoint hit time and
5213 vfork follow are detached. */
5214 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5216 /* This won't actually modify the breakpoint list, but will
5217 physically remove the breakpoints from the child. */
5218 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5221 delete_just_stopped_threads_single_step_breakpoints ();
5223 /* In case the event is caught by a catchpoint, remember that
5224 the event is to be followed at the next resume of the thread,
5225 and not immediately. */
5226 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5228 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5230 ecs
->event_thread
->control
.stop_bpstat
5231 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5232 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5234 if (handle_stop_requested (ecs
))
5237 /* If no catchpoint triggered for this, then keep going. Note
5238 that we're interested in knowing the bpstat actually causes a
5239 stop, not just if it may explain the signal. Software
5240 watchpoints, for example, always appear in the bpstat. */
5241 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5247 = (follow_fork_mode_string
== follow_fork_mode_child
);
5249 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5251 should_resume
= follow_fork ();
5254 child
= ecs
->ws
.value
.related_pid
;
5256 /* At this point, the parent is marked running, and the
5257 child is marked stopped. */
5259 /* If not resuming the parent, mark it stopped. */
5260 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5261 set_running (parent
, 0);
5263 /* If resuming the child, mark it running. */
5264 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5265 set_running (child
, 1);
5267 /* In non-stop mode, also resume the other branch. */
5268 if (!detach_fork
&& (non_stop
5269 || (sched_multi
&& target_is_non_stop_p ())))
5272 switch_to_thread (parent
);
5274 switch_to_thread (child
);
5276 ecs
->event_thread
= inferior_thread ();
5277 ecs
->ptid
= inferior_ptid
;
5282 switch_to_thread (child
);
5284 switch_to_thread (parent
);
5286 ecs
->event_thread
= inferior_thread ();
5287 ecs
->ptid
= inferior_ptid
;
5295 process_event_stop_test (ecs
);
5298 case TARGET_WAITKIND_VFORK_DONE
:
5299 /* Done with the shared memory region. Re-insert breakpoints in
5300 the parent, and keep going. */
5303 fprintf_unfiltered (gdb_stdlog
,
5304 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5306 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5307 context_switch (ecs
->ptid
);
5309 current_inferior ()->waiting_for_vfork_done
= 0;
5310 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5312 if (handle_stop_requested (ecs
))
5315 /* This also takes care of reinserting breakpoints in the
5316 previously locked inferior. */
5320 case TARGET_WAITKIND_EXECD
:
5322 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5324 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5325 context_switch (ecs
->ptid
);
5327 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5329 /* Do whatever is necessary to the parent branch of the vfork. */
5330 handle_vfork_child_exec_or_exit (1);
5332 /* This causes the eventpoints and symbol table to be reset.
5333 Must do this now, before trying to determine whether to
5335 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5337 /* In follow_exec we may have deleted the original thread and
5338 created a new one. Make sure that the event thread is the
5339 execd thread for that case (this is a nop otherwise). */
5340 ecs
->event_thread
= inferior_thread ();
5342 ecs
->event_thread
->control
.stop_bpstat
5343 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5344 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5346 /* Note that this may be referenced from inside
5347 bpstat_stop_status above, through inferior_has_execd. */
5348 xfree (ecs
->ws
.value
.execd_pathname
);
5349 ecs
->ws
.value
.execd_pathname
= NULL
;
5351 if (handle_stop_requested (ecs
))
5354 /* If no catchpoint triggered for this, then keep going. */
5355 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5357 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5361 process_event_stop_test (ecs
);
5364 /* Be careful not to try to gather much state about a thread
5365 that's in a syscall. It's frequently a losing proposition. */
5366 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5368 fprintf_unfiltered (gdb_stdlog
,
5369 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5370 /* Getting the current syscall number. */
5371 if (handle_syscall_event (ecs
) == 0)
5372 process_event_stop_test (ecs
);
5375 /* Before examining the threads further, step this thread to
5376 get it entirely out of the syscall. (We get notice of the
5377 event when the thread is just on the verge of exiting a
5378 syscall. Stepping one instruction seems to get it back
5380 case TARGET_WAITKIND_SYSCALL_RETURN
:
5382 fprintf_unfiltered (gdb_stdlog
,
5383 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5384 if (handle_syscall_event (ecs
) == 0)
5385 process_event_stop_test (ecs
);
5388 case TARGET_WAITKIND_STOPPED
:
5390 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5391 handle_signal_stop (ecs
);
5394 case TARGET_WAITKIND_NO_HISTORY
:
5396 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5397 /* Reverse execution: target ran out of history info. */
5399 /* Switch to the stopped thread. */
5400 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5401 context_switch (ecs
->ptid
);
5403 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5405 delete_just_stopped_threads_single_step_breakpoints ();
5406 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5408 if (handle_stop_requested (ecs
))
5411 observer_notify_no_history ();
5417 /* A wrapper around handle_inferior_event_1, which also makes sure
5418 that all temporary struct value objects that were created during
5419 the handling of the event get deleted at the end. */
5422 handle_inferior_event (struct execution_control_state
*ecs
)
5424 struct value
*mark
= value_mark ();
5426 handle_inferior_event_1 (ecs
);
5427 /* Purge all temporary values created during the event handling,
5428 as it could be a long time before we return to the command level
5429 where such values would otherwise be purged. */
5430 value_free_to_mark (mark
);
5433 /* Restart threads back to what they were trying to do back when we
5434 paused them for an in-line step-over. The EVENT_THREAD thread is
5438 restart_threads (struct thread_info
*event_thread
)
5440 struct thread_info
*tp
;
5442 /* In case the instruction just stepped spawned a new thread. */
5443 update_thread_list ();
5445 ALL_NON_EXITED_THREADS (tp
)
5447 if (tp
== event_thread
)
5450 fprintf_unfiltered (gdb_stdlog
,
5451 "infrun: restart threads: "
5452 "[%s] is event thread\n",
5453 target_pid_to_str (tp
->ptid
));
5457 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5460 fprintf_unfiltered (gdb_stdlog
,
5461 "infrun: restart threads: "
5462 "[%s] not meant to be running\n",
5463 target_pid_to_str (tp
->ptid
));
5470 fprintf_unfiltered (gdb_stdlog
,
5471 "infrun: restart threads: [%s] resumed\n",
5472 target_pid_to_str (tp
->ptid
));
5473 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5477 if (thread_is_in_step_over_chain (tp
))
5480 fprintf_unfiltered (gdb_stdlog
,
5481 "infrun: restart threads: "
5482 "[%s] needs step-over\n",
5483 target_pid_to_str (tp
->ptid
));
5484 gdb_assert (!tp
->resumed
);
5489 if (tp
->suspend
.waitstatus_pending_p
)
5492 fprintf_unfiltered (gdb_stdlog
,
5493 "infrun: restart threads: "
5494 "[%s] has pending status\n",
5495 target_pid_to_str (tp
->ptid
));
5500 gdb_assert (!tp
->stop_requested
);
5502 /* If some thread needs to start a step-over at this point, it
5503 should still be in the step-over queue, and thus skipped
5505 if (thread_still_needs_step_over (tp
))
5507 internal_error (__FILE__
, __LINE__
,
5508 "thread [%s] needs a step-over, but not in "
5509 "step-over queue\n",
5510 target_pid_to_str (tp
->ptid
));
5513 if (currently_stepping (tp
))
5516 fprintf_unfiltered (gdb_stdlog
,
5517 "infrun: restart threads: [%s] was stepping\n",
5518 target_pid_to_str (tp
->ptid
));
5519 keep_going_stepped_thread (tp
);
5523 struct execution_control_state ecss
;
5524 struct execution_control_state
*ecs
= &ecss
;
5527 fprintf_unfiltered (gdb_stdlog
,
5528 "infrun: restart threads: [%s] continuing\n",
5529 target_pid_to_str (tp
->ptid
));
5530 reset_ecs (ecs
, tp
);
5531 switch_to_thread (tp
->ptid
);
5532 keep_going_pass_signal (ecs
);
5537 /* Callback for iterate_over_threads. Find a resumed thread that has
5538 a pending waitstatus. */
5541 resumed_thread_with_pending_status (struct thread_info
*tp
,
5545 && tp
->suspend
.waitstatus_pending_p
);
5548 /* Called when we get an event that may finish an in-line or
5549 out-of-line (displaced stepping) step-over started previously.
5550 Return true if the event is processed and we should go back to the
5551 event loop; false if the caller should continue processing the
5555 finish_step_over (struct execution_control_state
*ecs
)
5557 int had_step_over_info
;
5559 displaced_step_fixup (ecs
->ptid
,
5560 ecs
->event_thread
->suspend
.stop_signal
);
5562 had_step_over_info
= step_over_info_valid_p ();
5564 if (had_step_over_info
)
5566 /* If we're stepping over a breakpoint with all threads locked,
5567 then only the thread that was stepped should be reporting
5569 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5571 clear_step_over_info ();
5574 if (!target_is_non_stop_p ())
5577 /* Start a new step-over in another thread if there's one that
5581 /* If we were stepping over a breakpoint before, and haven't started
5582 a new in-line step-over sequence, then restart all other threads
5583 (except the event thread). We can't do this in all-stop, as then
5584 e.g., we wouldn't be able to issue any other remote packet until
5585 these other threads stop. */
5586 if (had_step_over_info
&& !step_over_info_valid_p ())
5588 struct thread_info
*pending
;
5590 /* If we only have threads with pending statuses, the restart
5591 below won't restart any thread and so nothing re-inserts the
5592 breakpoint we just stepped over. But we need it inserted
5593 when we later process the pending events, otherwise if
5594 another thread has a pending event for this breakpoint too,
5595 we'd discard its event (because the breakpoint that
5596 originally caused the event was no longer inserted). */
5597 context_switch (ecs
->ptid
);
5598 insert_breakpoints ();
5600 restart_threads (ecs
->event_thread
);
5602 /* If we have events pending, go through handle_inferior_event
5603 again, picking up a pending event at random. This avoids
5604 thread starvation. */
5606 /* But not if we just stepped over a watchpoint in order to let
5607 the instruction execute so we can evaluate its expression.
5608 The set of watchpoints that triggered is recorded in the
5609 breakpoint objects themselves (see bp->watchpoint_triggered).
5610 If we processed another event first, that other event could
5611 clobber this info. */
5612 if (ecs
->event_thread
->stepping_over_watchpoint
)
5615 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5617 if (pending
!= NULL
)
5619 struct thread_info
*tp
= ecs
->event_thread
;
5620 struct regcache
*regcache
;
5624 fprintf_unfiltered (gdb_stdlog
,
5625 "infrun: found resumed threads with "
5626 "pending events, saving status\n");
5629 gdb_assert (pending
!= tp
);
5631 /* Record the event thread's event for later. */
5632 save_waitstatus (tp
, &ecs
->ws
);
5633 /* This was cleared early, by handle_inferior_event. Set it
5634 so this pending event is considered by
5638 gdb_assert (!tp
->executing
);
5640 regcache
= get_thread_regcache (tp
->ptid
);
5641 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5645 fprintf_unfiltered (gdb_stdlog
,
5646 "infrun: saved stop_pc=%s for %s "
5647 "(currently_stepping=%d)\n",
5648 paddress (target_gdbarch (),
5649 tp
->suspend
.stop_pc
),
5650 target_pid_to_str (tp
->ptid
),
5651 currently_stepping (tp
));
5654 /* This in-line step-over finished; clear this so we won't
5655 start a new one. This is what handle_signal_stop would
5656 do, if we returned false. */
5657 tp
->stepping_over_breakpoint
= 0;
5659 /* Wake up the event loop again. */
5660 mark_async_event_handler (infrun_async_inferior_event_token
);
5662 prepare_to_wait (ecs
);
5670 /* Come here when the program has stopped with a signal. */
5673 handle_signal_stop (struct execution_control_state
*ecs
)
5675 struct frame_info
*frame
;
5676 struct gdbarch
*gdbarch
;
5677 int stopped_by_watchpoint
;
5678 enum stop_kind stop_soon
;
5681 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5683 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5685 /* Do we need to clean up the state of a thread that has
5686 completed a displaced single-step? (Doing so usually affects
5687 the PC, so do it here, before we set stop_pc.) */
5688 if (finish_step_over (ecs
))
5691 /* If we either finished a single-step or hit a breakpoint, but
5692 the user wanted this thread to be stopped, pretend we got a
5693 SIG0 (generic unsignaled stop). */
5694 if (ecs
->event_thread
->stop_requested
5695 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5696 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5698 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5702 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5703 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5704 struct cleanup
*old_chain
= save_inferior_ptid ();
5706 inferior_ptid
= ecs
->ptid
;
5708 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5709 paddress (gdbarch
, stop_pc
));
5710 if (target_stopped_by_watchpoint ())
5714 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5716 if (target_stopped_data_address (¤t_target
, &addr
))
5717 fprintf_unfiltered (gdb_stdlog
,
5718 "infrun: stopped data address = %s\n",
5719 paddress (gdbarch
, addr
));
5721 fprintf_unfiltered (gdb_stdlog
,
5722 "infrun: (no data address available)\n");
5725 do_cleanups (old_chain
);
5728 /* This is originated from start_remote(), start_inferior() and
5729 shared libraries hook functions. */
5730 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5731 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5733 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5734 context_switch (ecs
->ptid
);
5736 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5737 stop_print_frame
= 1;
5742 /* This originates from attach_command(). We need to overwrite
5743 the stop_signal here, because some kernels don't ignore a
5744 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5745 See more comments in inferior.h. On the other hand, if we
5746 get a non-SIGSTOP, report it to the user - assume the backend
5747 will handle the SIGSTOP if it should show up later.
5749 Also consider that the attach is complete when we see a
5750 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5751 target extended-remote report it instead of a SIGSTOP
5752 (e.g. gdbserver). We already rely on SIGTRAP being our
5753 signal, so this is no exception.
5755 Also consider that the attach is complete when we see a
5756 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5757 the target to stop all threads of the inferior, in case the
5758 low level attach operation doesn't stop them implicitly. If
5759 they weren't stopped implicitly, then the stub will report a
5760 GDB_SIGNAL_0, meaning: stopped for no particular reason
5761 other than GDB's request. */
5762 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5763 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5764 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5765 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5767 stop_print_frame
= 1;
5769 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5773 /* See if something interesting happened to the non-current thread. If
5774 so, then switch to that thread. */
5775 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5778 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5780 context_switch (ecs
->ptid
);
5782 if (deprecated_context_hook
)
5783 deprecated_context_hook (ptid_to_global_thread_id (ecs
->ptid
));
5786 /* At this point, get hold of the now-current thread's frame. */
5787 frame
= get_current_frame ();
5788 gdbarch
= get_frame_arch (frame
);
5790 /* Pull the single step breakpoints out of the target. */
5791 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5793 struct regcache
*regcache
;
5794 struct address_space
*aspace
;
5797 regcache
= get_thread_regcache (ecs
->ptid
);
5798 aspace
= get_regcache_aspace (regcache
);
5799 pc
= regcache_read_pc (regcache
);
5801 /* However, before doing so, if this single-step breakpoint was
5802 actually for another thread, set this thread up for moving
5804 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5807 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5811 fprintf_unfiltered (gdb_stdlog
,
5812 "infrun: [%s] hit another thread's "
5813 "single-step breakpoint\n",
5814 target_pid_to_str (ecs
->ptid
));
5816 ecs
->hit_singlestep_breakpoint
= 1;
5823 fprintf_unfiltered (gdb_stdlog
,
5824 "infrun: [%s] hit its "
5825 "single-step breakpoint\n",
5826 target_pid_to_str (ecs
->ptid
));
5830 delete_just_stopped_threads_single_step_breakpoints ();
5832 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5833 && ecs
->event_thread
->control
.trap_expected
5834 && ecs
->event_thread
->stepping_over_watchpoint
)
5835 stopped_by_watchpoint
= 0;
5837 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5839 /* If necessary, step over this watchpoint. We'll be back to display
5841 if (stopped_by_watchpoint
5842 && (target_have_steppable_watchpoint
5843 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5845 /* At this point, we are stopped at an instruction which has
5846 attempted to write to a piece of memory under control of
5847 a watchpoint. The instruction hasn't actually executed
5848 yet. If we were to evaluate the watchpoint expression
5849 now, we would get the old value, and therefore no change
5850 would seem to have occurred.
5852 In order to make watchpoints work `right', we really need
5853 to complete the memory write, and then evaluate the
5854 watchpoint expression. We do this by single-stepping the
5857 It may not be necessary to disable the watchpoint to step over
5858 it. For example, the PA can (with some kernel cooperation)
5859 single step over a watchpoint without disabling the watchpoint.
5861 It is far more common to need to disable a watchpoint to step
5862 the inferior over it. If we have non-steppable watchpoints,
5863 we must disable the current watchpoint; it's simplest to
5864 disable all watchpoints.
5866 Any breakpoint at PC must also be stepped over -- if there's
5867 one, it will have already triggered before the watchpoint
5868 triggered, and we either already reported it to the user, or
5869 it didn't cause a stop and we called keep_going. In either
5870 case, if there was a breakpoint at PC, we must be trying to
5872 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5877 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5878 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5879 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5880 ecs
->event_thread
->control
.stop_step
= 0;
5881 stop_print_frame
= 1;
5882 stopped_by_random_signal
= 0;
5884 /* Hide inlined functions starting here, unless we just performed stepi or
5885 nexti. After stepi and nexti, always show the innermost frame (not any
5886 inline function call sites). */
5887 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5889 struct address_space
*aspace
=
5890 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5892 /* skip_inline_frames is expensive, so we avoid it if we can
5893 determine that the address is one where functions cannot have
5894 been inlined. This improves performance with inferiors that
5895 load a lot of shared libraries, because the solib event
5896 breakpoint is defined as the address of a function (i.e. not
5897 inline). Note that we have to check the previous PC as well
5898 as the current one to catch cases when we have just
5899 single-stepped off a breakpoint prior to reinstating it.
5900 Note that we're assuming that the code we single-step to is
5901 not inline, but that's not definitive: there's nothing
5902 preventing the event breakpoint function from containing
5903 inlined code, and the single-step ending up there. If the
5904 user had set a breakpoint on that inlined code, the missing
5905 skip_inline_frames call would break things. Fortunately
5906 that's an extremely unlikely scenario. */
5907 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5908 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5909 && ecs
->event_thread
->control
.trap_expected
5910 && pc_at_non_inline_function (aspace
,
5911 ecs
->event_thread
->prev_pc
,
5914 skip_inline_frames (ecs
->ptid
);
5916 /* Re-fetch current thread's frame in case that invalidated
5918 frame
= get_current_frame ();
5919 gdbarch
= get_frame_arch (frame
);
5923 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5924 && ecs
->event_thread
->control
.trap_expected
5925 && gdbarch_single_step_through_delay_p (gdbarch
)
5926 && currently_stepping (ecs
->event_thread
))
5928 /* We're trying to step off a breakpoint. Turns out that we're
5929 also on an instruction that needs to be stepped multiple
5930 times before it's been fully executing. E.g., architectures
5931 with a delay slot. It needs to be stepped twice, once for
5932 the instruction and once for the delay slot. */
5933 int step_through_delay
5934 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5936 if (debug_infrun
&& step_through_delay
)
5937 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5938 if (ecs
->event_thread
->control
.step_range_end
== 0
5939 && step_through_delay
)
5941 /* The user issued a continue when stopped at a breakpoint.
5942 Set up for another trap and get out of here. */
5943 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5947 else if (step_through_delay
)
5949 /* The user issued a step when stopped at a breakpoint.
5950 Maybe we should stop, maybe we should not - the delay
5951 slot *might* correspond to a line of source. In any
5952 case, don't decide that here, just set
5953 ecs->stepping_over_breakpoint, making sure we
5954 single-step again before breakpoints are re-inserted. */
5955 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5959 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5960 handles this event. */
5961 ecs
->event_thread
->control
.stop_bpstat
5962 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5963 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5965 /* Following in case break condition called a
5967 stop_print_frame
= 1;
5969 /* This is where we handle "moribund" watchpoints. Unlike
5970 software breakpoints traps, hardware watchpoint traps are
5971 always distinguishable from random traps. If no high-level
5972 watchpoint is associated with the reported stop data address
5973 anymore, then the bpstat does not explain the signal ---
5974 simply make sure to ignore it if `stopped_by_watchpoint' is
5978 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5979 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5981 && stopped_by_watchpoint
)
5982 fprintf_unfiltered (gdb_stdlog
,
5983 "infrun: no user watchpoint explains "
5984 "watchpoint SIGTRAP, ignoring\n");
5986 /* NOTE: cagney/2003-03-29: These checks for a random signal
5987 at one stage in the past included checks for an inferior
5988 function call's call dummy's return breakpoint. The original
5989 comment, that went with the test, read:
5991 ``End of a stack dummy. Some systems (e.g. Sony news) give
5992 another signal besides SIGTRAP, so check here as well as
5995 If someone ever tries to get call dummys on a
5996 non-executable stack to work (where the target would stop
5997 with something like a SIGSEGV), then those tests might need
5998 to be re-instated. Given, however, that the tests were only
5999 enabled when momentary breakpoints were not being used, I
6000 suspect that it won't be the case.
6002 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
6003 be necessary for call dummies on a non-executable stack on
6006 /* See if the breakpoints module can explain the signal. */
6008 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6009 ecs
->event_thread
->suspend
.stop_signal
);
6011 /* Maybe this was a trap for a software breakpoint that has since
6013 if (random_signal
&& target_stopped_by_sw_breakpoint ())
6015 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
6017 struct regcache
*regcache
;
6020 /* Re-adjust PC to what the program would see if GDB was not
6022 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
6023 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6026 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
6028 if (record_full_is_used ())
6029 record_full_gdb_operation_disable_set ();
6031 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
6033 do_cleanups (old_cleanups
);
6038 /* A delayed software breakpoint event. Ignore the trap. */
6040 fprintf_unfiltered (gdb_stdlog
,
6041 "infrun: delayed software breakpoint "
6042 "trap, ignoring\n");
6047 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6048 has since been removed. */
6049 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6051 /* A delayed hardware breakpoint event. Ignore the trap. */
6053 fprintf_unfiltered (gdb_stdlog
,
6054 "infrun: delayed hardware breakpoint/watchpoint "
6055 "trap, ignoring\n");
6059 /* If not, perhaps stepping/nexting can. */
6061 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6062 && currently_stepping (ecs
->event_thread
));
6064 /* Perhaps the thread hit a single-step breakpoint of _another_
6065 thread. Single-step breakpoints are transparent to the
6066 breakpoints module. */
6068 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6070 /* No? Perhaps we got a moribund watchpoint. */
6072 random_signal
= !stopped_by_watchpoint
;
6074 /* Always stop if the user explicitly requested this thread to
6076 if (ecs
->event_thread
->stop_requested
)
6080 fprintf_unfiltered (gdb_stdlog
, "infrun: user-requested stop\n");
6083 /* For the program's own signals, act according to
6084 the signal handling tables. */
6088 /* Signal not for debugging purposes. */
6089 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
6090 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6093 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
6094 gdb_signal_to_symbol_string (stop_signal
));
6096 stopped_by_random_signal
= 1;
6098 /* Always stop on signals if we're either just gaining control
6099 of the program, or the user explicitly requested this thread
6100 to remain stopped. */
6101 if (stop_soon
!= NO_STOP_QUIETLY
6102 || ecs
->event_thread
->stop_requested
6104 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
6110 /* Notify observers the signal has "handle print" set. Note we
6111 returned early above if stopping; normal_stop handles the
6112 printing in that case. */
6113 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6115 /* The signal table tells us to print about this signal. */
6116 target_terminal_ours_for_output ();
6117 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
6118 target_terminal_inferior ();
6121 /* Clear the signal if it should not be passed. */
6122 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6123 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6125 if (ecs
->event_thread
->prev_pc
== stop_pc
6126 && ecs
->event_thread
->control
.trap_expected
6127 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6129 /* We were just starting a new sequence, attempting to
6130 single-step off of a breakpoint and expecting a SIGTRAP.
6131 Instead this signal arrives. This signal will take us out
6132 of the stepping range so GDB needs to remember to, when
6133 the signal handler returns, resume stepping off that
6135 /* To simplify things, "continue" is forced to use the same
6136 code paths as single-step - set a breakpoint at the
6137 signal return address and then, once hit, step off that
6140 fprintf_unfiltered (gdb_stdlog
,
6141 "infrun: signal arrived while stepping over "
6144 insert_hp_step_resume_breakpoint_at_frame (frame
);
6145 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6146 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6147 ecs
->event_thread
->control
.trap_expected
= 0;
6149 /* If we were nexting/stepping some other thread, switch to
6150 it, so that we don't continue it, losing control. */
6151 if (!switch_back_to_stepped_thread (ecs
))
6156 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6157 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6158 || ecs
->event_thread
->control
.step_range_end
== 1)
6159 && frame_id_eq (get_stack_frame_id (frame
),
6160 ecs
->event_thread
->control
.step_stack_frame_id
)
6161 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6163 /* The inferior is about to take a signal that will take it
6164 out of the single step range. Set a breakpoint at the
6165 current PC (which is presumably where the signal handler
6166 will eventually return) and then allow the inferior to
6169 Note that this is only needed for a signal delivered
6170 while in the single-step range. Nested signals aren't a
6171 problem as they eventually all return. */
6173 fprintf_unfiltered (gdb_stdlog
,
6174 "infrun: signal may take us out of "
6175 "single-step range\n");
6177 clear_step_over_info ();
6178 insert_hp_step_resume_breakpoint_at_frame (frame
);
6179 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6180 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6181 ecs
->event_thread
->control
.trap_expected
= 0;
6186 /* Note: step_resume_breakpoint may be non-NULL. This occures
6187 when either there's a nested signal, or when there's a
6188 pending signal enabled just as the signal handler returns
6189 (leaving the inferior at the step-resume-breakpoint without
6190 actually executing it). Either way continue until the
6191 breakpoint is really hit. */
6193 if (!switch_back_to_stepped_thread (ecs
))
6196 fprintf_unfiltered (gdb_stdlog
,
6197 "infrun: random signal, keep going\n");
6204 process_event_stop_test (ecs
);
6207 /* Come here when we've got some debug event / signal we can explain
6208 (IOW, not a random signal), and test whether it should cause a
6209 stop, or whether we should resume the inferior (transparently).
6210 E.g., could be a breakpoint whose condition evaluates false; we
6211 could be still stepping within the line; etc. */
6214 process_event_stop_test (struct execution_control_state
*ecs
)
6216 struct symtab_and_line stop_pc_sal
;
6217 struct frame_info
*frame
;
6218 struct gdbarch
*gdbarch
;
6219 CORE_ADDR jmp_buf_pc
;
6220 struct bpstat_what what
;
6222 /* Handle cases caused by hitting a breakpoint. */
6224 frame
= get_current_frame ();
6225 gdbarch
= get_frame_arch (frame
);
6227 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6229 if (what
.call_dummy
)
6231 stop_stack_dummy
= what
.call_dummy
;
6234 /* A few breakpoint types have callbacks associated (e.g.,
6235 bp_jit_event). Run them now. */
6236 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6238 /* If we hit an internal event that triggers symbol changes, the
6239 current frame will be invalidated within bpstat_what (e.g., if we
6240 hit an internal solib event). Re-fetch it. */
6241 frame
= get_current_frame ();
6242 gdbarch
= get_frame_arch (frame
);
6244 switch (what
.main_action
)
6246 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6247 /* If we hit the breakpoint at longjmp while stepping, we
6248 install a momentary breakpoint at the target of the
6252 fprintf_unfiltered (gdb_stdlog
,
6253 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6255 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6257 if (what
.is_longjmp
)
6259 struct value
*arg_value
;
6261 /* If we set the longjmp breakpoint via a SystemTap probe,
6262 then use it to extract the arguments. The destination PC
6263 is the third argument to the probe. */
6264 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6267 jmp_buf_pc
= value_as_address (arg_value
);
6268 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6270 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6271 || !gdbarch_get_longjmp_target (gdbarch
,
6272 frame
, &jmp_buf_pc
))
6275 fprintf_unfiltered (gdb_stdlog
,
6276 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6277 "(!gdbarch_get_longjmp_target)\n");
6282 /* Insert a breakpoint at resume address. */
6283 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6286 check_exception_resume (ecs
, frame
);
6290 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6292 struct frame_info
*init_frame
;
6294 /* There are several cases to consider.
6296 1. The initiating frame no longer exists. In this case we
6297 must stop, because the exception or longjmp has gone too
6300 2. The initiating frame exists, and is the same as the
6301 current frame. We stop, because the exception or longjmp
6304 3. The initiating frame exists and is different from the
6305 current frame. This means the exception or longjmp has
6306 been caught beneath the initiating frame, so keep going.
6308 4. longjmp breakpoint has been placed just to protect
6309 against stale dummy frames and user is not interested in
6310 stopping around longjmps. */
6313 fprintf_unfiltered (gdb_stdlog
,
6314 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6316 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6318 delete_exception_resume_breakpoint (ecs
->event_thread
);
6320 if (what
.is_longjmp
)
6322 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6324 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6332 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6336 struct frame_id current_id
6337 = get_frame_id (get_current_frame ());
6338 if (frame_id_eq (current_id
,
6339 ecs
->event_thread
->initiating_frame
))
6341 /* Case 2. Fall through. */
6351 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6353 delete_step_resume_breakpoint (ecs
->event_thread
);
6355 end_stepping_range (ecs
);
6359 case BPSTAT_WHAT_SINGLE
:
6361 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6362 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6363 /* Still need to check other stuff, at least the case where we
6364 are stepping and step out of the right range. */
6367 case BPSTAT_WHAT_STEP_RESUME
:
6369 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6371 delete_step_resume_breakpoint (ecs
->event_thread
);
6372 if (ecs
->event_thread
->control
.proceed_to_finish
6373 && execution_direction
== EXEC_REVERSE
)
6375 struct thread_info
*tp
= ecs
->event_thread
;
6377 /* We are finishing a function in reverse, and just hit the
6378 step-resume breakpoint at the start address of the
6379 function, and we're almost there -- just need to back up
6380 by one more single-step, which should take us back to the
6382 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6386 fill_in_stop_func (gdbarch
, ecs
);
6387 if (stop_pc
== ecs
->stop_func_start
6388 && execution_direction
== EXEC_REVERSE
)
6390 /* We are stepping over a function call in reverse, and just
6391 hit the step-resume breakpoint at the start address of
6392 the function. Go back to single-stepping, which should
6393 take us back to the function call. */
6394 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6400 case BPSTAT_WHAT_STOP_NOISY
:
6402 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6403 stop_print_frame
= 1;
6405 /* Assume the thread stopped for a breapoint. We'll still check
6406 whether a/the breakpoint is there when the thread is next
6408 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6413 case BPSTAT_WHAT_STOP_SILENT
:
6415 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6416 stop_print_frame
= 0;
6418 /* Assume the thread stopped for a breapoint. We'll still check
6419 whether a/the breakpoint is there when the thread is next
6421 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6425 case BPSTAT_WHAT_HP_STEP_RESUME
:
6427 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6429 delete_step_resume_breakpoint (ecs
->event_thread
);
6430 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6432 /* Back when the step-resume breakpoint was inserted, we
6433 were trying to single-step off a breakpoint. Go back to
6435 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6436 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6442 case BPSTAT_WHAT_KEEP_CHECKING
:
6446 /* If we stepped a permanent breakpoint and we had a high priority
6447 step-resume breakpoint for the address we stepped, but we didn't
6448 hit it, then we must have stepped into the signal handler. The
6449 step-resume was only necessary to catch the case of _not_
6450 stepping into the handler, so delete it, and fall through to
6451 checking whether the step finished. */
6452 if (ecs
->event_thread
->stepped_breakpoint
)
6454 struct breakpoint
*sr_bp
6455 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6458 && sr_bp
->loc
->permanent
6459 && sr_bp
->type
== bp_hp_step_resume
6460 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6463 fprintf_unfiltered (gdb_stdlog
,
6464 "infrun: stepped permanent breakpoint, stopped in "
6466 delete_step_resume_breakpoint (ecs
->event_thread
);
6467 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6471 /* We come here if we hit a breakpoint but should not stop for it.
6472 Possibly we also were stepping and should stop for that. So fall
6473 through and test for stepping. But, if not stepping, do not
6476 /* In all-stop mode, if we're currently stepping but have stopped in
6477 some other thread, we need to switch back to the stepped thread. */
6478 if (switch_back_to_stepped_thread (ecs
))
6481 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6484 fprintf_unfiltered (gdb_stdlog
,
6485 "infrun: step-resume breakpoint is inserted\n");
6487 /* Having a step-resume breakpoint overrides anything
6488 else having to do with stepping commands until
6489 that breakpoint is reached. */
6494 if (ecs
->event_thread
->control
.step_range_end
== 0)
6497 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6498 /* Likewise if we aren't even stepping. */
6503 /* Re-fetch current thread's frame in case the code above caused
6504 the frame cache to be re-initialized, making our FRAME variable
6505 a dangling pointer. */
6506 frame
= get_current_frame ();
6507 gdbarch
= get_frame_arch (frame
);
6508 fill_in_stop_func (gdbarch
, ecs
);
6510 /* If stepping through a line, keep going if still within it.
6512 Note that step_range_end is the address of the first instruction
6513 beyond the step range, and NOT the address of the last instruction
6516 Note also that during reverse execution, we may be stepping
6517 through a function epilogue and therefore must detect when
6518 the current-frame changes in the middle of a line. */
6520 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6521 && (execution_direction
!= EXEC_REVERSE
6522 || frame_id_eq (get_frame_id (frame
),
6523 ecs
->event_thread
->control
.step_frame_id
)))
6527 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6528 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6529 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6531 /* Tentatively re-enable range stepping; `resume' disables it if
6532 necessary (e.g., if we're stepping over a breakpoint or we
6533 have software watchpoints). */
6534 ecs
->event_thread
->control
.may_range_step
= 1;
6536 /* When stepping backward, stop at beginning of line range
6537 (unless it's the function entry point, in which case
6538 keep going back to the call point). */
6539 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6540 && stop_pc
!= ecs
->stop_func_start
6541 && execution_direction
== EXEC_REVERSE
)
6542 end_stepping_range (ecs
);
6549 /* We stepped out of the stepping range. */
6551 /* If we are stepping at the source level and entered the runtime
6552 loader dynamic symbol resolution code...
6554 EXEC_FORWARD: we keep on single stepping until we exit the run
6555 time loader code and reach the callee's address.
6557 EXEC_REVERSE: we've already executed the callee (backward), and
6558 the runtime loader code is handled just like any other
6559 undebuggable function call. Now we need only keep stepping
6560 backward through the trampoline code, and that's handled further
6561 down, so there is nothing for us to do here. */
6563 if (execution_direction
!= EXEC_REVERSE
6564 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6565 && in_solib_dynsym_resolve_code (stop_pc
))
6567 CORE_ADDR pc_after_resolver
=
6568 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6571 fprintf_unfiltered (gdb_stdlog
,
6572 "infrun: stepped into dynsym resolve code\n");
6574 if (pc_after_resolver
)
6576 /* Set up a step-resume breakpoint at the address
6577 indicated by SKIP_SOLIB_RESOLVER. */
6578 struct symtab_and_line sr_sal
;
6581 sr_sal
.pc
= pc_after_resolver
;
6582 sr_sal
.pspace
= get_frame_program_space (frame
);
6584 insert_step_resume_breakpoint_at_sal (gdbarch
,
6585 sr_sal
, null_frame_id
);
6592 if (ecs
->event_thread
->control
.step_range_end
!= 1
6593 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6594 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6595 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6598 fprintf_unfiltered (gdb_stdlog
,
6599 "infrun: stepped into signal trampoline\n");
6600 /* The inferior, while doing a "step" or "next", has ended up in
6601 a signal trampoline (either by a signal being delivered or by
6602 the signal handler returning). Just single-step until the
6603 inferior leaves the trampoline (either by calling the handler
6609 /* If we're in the return path from a shared library trampoline,
6610 we want to proceed through the trampoline when stepping. */
6611 /* macro/2012-04-25: This needs to come before the subroutine
6612 call check below as on some targets return trampolines look
6613 like subroutine calls (MIPS16 return thunks). */
6614 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6615 stop_pc
, ecs
->stop_func_name
)
6616 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6618 /* Determine where this trampoline returns. */
6619 CORE_ADDR real_stop_pc
;
6621 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6624 fprintf_unfiltered (gdb_stdlog
,
6625 "infrun: stepped into solib return tramp\n");
6627 /* Only proceed through if we know where it's going. */
6630 /* And put the step-breakpoint there and go until there. */
6631 struct symtab_and_line sr_sal
;
6633 init_sal (&sr_sal
); /* initialize to zeroes */
6634 sr_sal
.pc
= real_stop_pc
;
6635 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6636 sr_sal
.pspace
= get_frame_program_space (frame
);
6638 /* Do not specify what the fp should be when we stop since
6639 on some machines the prologue is where the new fp value
6641 insert_step_resume_breakpoint_at_sal (gdbarch
,
6642 sr_sal
, null_frame_id
);
6644 /* Restart without fiddling with the step ranges or
6651 /* Check for subroutine calls. The check for the current frame
6652 equalling the step ID is not necessary - the check of the
6653 previous frame's ID is sufficient - but it is a common case and
6654 cheaper than checking the previous frame's ID.
6656 NOTE: frame_id_eq will never report two invalid frame IDs as
6657 being equal, so to get into this block, both the current and
6658 previous frame must have valid frame IDs. */
6659 /* The outer_frame_id check is a heuristic to detect stepping
6660 through startup code. If we step over an instruction which
6661 sets the stack pointer from an invalid value to a valid value,
6662 we may detect that as a subroutine call from the mythical
6663 "outermost" function. This could be fixed by marking
6664 outermost frames as !stack_p,code_p,special_p. Then the
6665 initial outermost frame, before sp was valid, would
6666 have code_addr == &_start. See the comment in frame_id_eq
6668 if (!frame_id_eq (get_stack_frame_id (frame
),
6669 ecs
->event_thread
->control
.step_stack_frame_id
)
6670 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6671 ecs
->event_thread
->control
.step_stack_frame_id
)
6672 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6674 || (ecs
->event_thread
->control
.step_start_function
6675 != find_pc_function (stop_pc
)))))
6677 CORE_ADDR real_stop_pc
;
6680 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6682 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6684 /* I presume that step_over_calls is only 0 when we're
6685 supposed to be stepping at the assembly language level
6686 ("stepi"). Just stop. */
6687 /* And this works the same backward as frontward. MVS */
6688 end_stepping_range (ecs
);
6692 /* Reverse stepping through solib trampolines. */
6694 if (execution_direction
== EXEC_REVERSE
6695 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6696 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6697 || (ecs
->stop_func_start
== 0
6698 && in_solib_dynsym_resolve_code (stop_pc
))))
6700 /* Any solib trampoline code can be handled in reverse
6701 by simply continuing to single-step. We have already
6702 executed the solib function (backwards), and a few
6703 steps will take us back through the trampoline to the
6709 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6711 /* We're doing a "next".
6713 Normal (forward) execution: set a breakpoint at the
6714 callee's return address (the address at which the caller
6717 Reverse (backward) execution. set the step-resume
6718 breakpoint at the start of the function that we just
6719 stepped into (backwards), and continue to there. When we
6720 get there, we'll need to single-step back to the caller. */
6722 if (execution_direction
== EXEC_REVERSE
)
6724 /* If we're already at the start of the function, we've either
6725 just stepped backward into a single instruction function,
6726 or stepped back out of a signal handler to the first instruction
6727 of the function. Just keep going, which will single-step back
6729 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6731 struct symtab_and_line sr_sal
;
6733 /* Normal function call return (static or dynamic). */
6735 sr_sal
.pc
= ecs
->stop_func_start
;
6736 sr_sal
.pspace
= get_frame_program_space (frame
);
6737 insert_step_resume_breakpoint_at_sal (gdbarch
,
6738 sr_sal
, null_frame_id
);
6742 insert_step_resume_breakpoint_at_caller (frame
);
6748 /* If we are in a function call trampoline (a stub between the
6749 calling routine and the real function), locate the real
6750 function. That's what tells us (a) whether we want to step
6751 into it at all, and (b) what prologue we want to run to the
6752 end of, if we do step into it. */
6753 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6754 if (real_stop_pc
== 0)
6755 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6756 if (real_stop_pc
!= 0)
6757 ecs
->stop_func_start
= real_stop_pc
;
6759 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6761 struct symtab_and_line sr_sal
;
6764 sr_sal
.pc
= ecs
->stop_func_start
;
6765 sr_sal
.pspace
= get_frame_program_space (frame
);
6767 insert_step_resume_breakpoint_at_sal (gdbarch
,
6768 sr_sal
, null_frame_id
);
6773 /* If we have line number information for the function we are
6774 thinking of stepping into and the function isn't on the skip
6777 If there are several symtabs at that PC (e.g. with include
6778 files), just want to know whether *any* of them have line
6779 numbers. find_pc_line handles this. */
6781 struct symtab_and_line tmp_sal
;
6783 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6784 if (tmp_sal
.line
!= 0
6785 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6788 if (execution_direction
== EXEC_REVERSE
)
6789 handle_step_into_function_backward (gdbarch
, ecs
);
6791 handle_step_into_function (gdbarch
, ecs
);
6796 /* If we have no line number and the step-stop-if-no-debug is
6797 set, we stop the step so that the user has a chance to switch
6798 in assembly mode. */
6799 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6800 && step_stop_if_no_debug
)
6802 end_stepping_range (ecs
);
6806 if (execution_direction
== EXEC_REVERSE
)
6808 /* If we're already at the start of the function, we've either just
6809 stepped backward into a single instruction function without line
6810 number info, or stepped back out of a signal handler to the first
6811 instruction of the function without line number info. Just keep
6812 going, which will single-step back to the caller. */
6813 if (ecs
->stop_func_start
!= stop_pc
)
6815 /* Set a breakpoint at callee's start address.
6816 From there we can step once and be back in the caller. */
6817 struct symtab_and_line sr_sal
;
6820 sr_sal
.pc
= ecs
->stop_func_start
;
6821 sr_sal
.pspace
= get_frame_program_space (frame
);
6822 insert_step_resume_breakpoint_at_sal (gdbarch
,
6823 sr_sal
, null_frame_id
);
6827 /* Set a breakpoint at callee's return address (the address
6828 at which the caller will resume). */
6829 insert_step_resume_breakpoint_at_caller (frame
);
6835 /* Reverse stepping through solib trampolines. */
6837 if (execution_direction
== EXEC_REVERSE
6838 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6840 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6841 || (ecs
->stop_func_start
== 0
6842 && in_solib_dynsym_resolve_code (stop_pc
)))
6844 /* Any solib trampoline code can be handled in reverse
6845 by simply continuing to single-step. We have already
6846 executed the solib function (backwards), and a few
6847 steps will take us back through the trampoline to the
6852 else if (in_solib_dynsym_resolve_code (stop_pc
))
6854 /* Stepped backward into the solib dynsym resolver.
6855 Set a breakpoint at its start and continue, then
6856 one more step will take us out. */
6857 struct symtab_and_line sr_sal
;
6860 sr_sal
.pc
= ecs
->stop_func_start
;
6861 sr_sal
.pspace
= get_frame_program_space (frame
);
6862 insert_step_resume_breakpoint_at_sal (gdbarch
,
6863 sr_sal
, null_frame_id
);
6869 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6871 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6872 the trampoline processing logic, however, there are some trampolines
6873 that have no names, so we should do trampoline handling first. */
6874 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6875 && ecs
->stop_func_name
== NULL
6876 && stop_pc_sal
.line
== 0)
6879 fprintf_unfiltered (gdb_stdlog
,
6880 "infrun: stepped into undebuggable function\n");
6882 /* The inferior just stepped into, or returned to, an
6883 undebuggable function (where there is no debugging information
6884 and no line number corresponding to the address where the
6885 inferior stopped). Since we want to skip this kind of code,
6886 we keep going until the inferior returns from this
6887 function - unless the user has asked us not to (via
6888 set step-mode) or we no longer know how to get back
6889 to the call site. */
6890 if (step_stop_if_no_debug
6891 || !frame_id_p (frame_unwind_caller_id (frame
)))
6893 /* If we have no line number and the step-stop-if-no-debug
6894 is set, we stop the step so that the user has a chance to
6895 switch in assembly mode. */
6896 end_stepping_range (ecs
);
6901 /* Set a breakpoint at callee's return address (the address
6902 at which the caller will resume). */
6903 insert_step_resume_breakpoint_at_caller (frame
);
6909 if (ecs
->event_thread
->control
.step_range_end
== 1)
6911 /* It is stepi or nexti. We always want to stop stepping after
6914 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6915 end_stepping_range (ecs
);
6919 if (stop_pc_sal
.line
== 0)
6921 /* We have no line number information. That means to stop
6922 stepping (does this always happen right after one instruction,
6923 when we do "s" in a function with no line numbers,
6924 or can this happen as a result of a return or longjmp?). */
6926 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6927 end_stepping_range (ecs
);
6931 /* Look for "calls" to inlined functions, part one. If the inline
6932 frame machinery detected some skipped call sites, we have entered
6933 a new inline function. */
6935 if (frame_id_eq (get_frame_id (get_current_frame ()),
6936 ecs
->event_thread
->control
.step_frame_id
)
6937 && inline_skipped_frames (ecs
->ptid
))
6939 struct symtab_and_line call_sal
;
6942 fprintf_unfiltered (gdb_stdlog
,
6943 "infrun: stepped into inlined function\n");
6945 find_frame_sal (get_current_frame (), &call_sal
);
6947 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6949 /* For "step", we're going to stop. But if the call site
6950 for this inlined function is on the same source line as
6951 we were previously stepping, go down into the function
6952 first. Otherwise stop at the call site. */
6954 if (call_sal
.line
== ecs
->event_thread
->current_line
6955 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6956 step_into_inline_frame (ecs
->ptid
);
6958 end_stepping_range (ecs
);
6963 /* For "next", we should stop at the call site if it is on a
6964 different source line. Otherwise continue through the
6965 inlined function. */
6966 if (call_sal
.line
== ecs
->event_thread
->current_line
6967 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6970 end_stepping_range (ecs
);
6975 /* Look for "calls" to inlined functions, part two. If we are still
6976 in the same real function we were stepping through, but we have
6977 to go further up to find the exact frame ID, we are stepping
6978 through a more inlined call beyond its call site. */
6980 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6981 && !frame_id_eq (get_frame_id (get_current_frame ()),
6982 ecs
->event_thread
->control
.step_frame_id
)
6983 && stepped_in_from (get_current_frame (),
6984 ecs
->event_thread
->control
.step_frame_id
))
6987 fprintf_unfiltered (gdb_stdlog
,
6988 "infrun: stepping through inlined function\n");
6990 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6993 end_stepping_range (ecs
);
6997 if ((stop_pc
== stop_pc_sal
.pc
)
6998 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6999 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
7001 /* We are at the start of a different line. So stop. Note that
7002 we don't stop if we step into the middle of a different line.
7003 That is said to make things like for (;;) statements work
7006 fprintf_unfiltered (gdb_stdlog
,
7007 "infrun: stepped to a different line\n");
7008 end_stepping_range (ecs
);
7012 /* We aren't done stepping.
7014 Optimize by setting the stepping range to the line.
7015 (We might not be in the original line, but if we entered a
7016 new line in mid-statement, we continue stepping. This makes
7017 things like for(;;) statements work better.) */
7019 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7020 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7021 ecs
->event_thread
->control
.may_range_step
= 1;
7022 set_step_info (frame
, stop_pc_sal
);
7025 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
7029 /* In all-stop mode, if we're currently stepping but have stopped in
7030 some other thread, we may need to switch back to the stepped
7031 thread. Returns true we set the inferior running, false if we left
7032 it stopped (and the event needs further processing). */
7035 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7037 if (!target_is_non_stop_p ())
7039 struct thread_info
*tp
;
7040 struct thread_info
*stepping_thread
;
7042 /* If any thread is blocked on some internal breakpoint, and we
7043 simply need to step over that breakpoint to get it going
7044 again, do that first. */
7046 /* However, if we see an event for the stepping thread, then we
7047 know all other threads have been moved past their breakpoints
7048 already. Let the caller check whether the step is finished,
7049 etc., before deciding to move it past a breakpoint. */
7050 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7053 /* Check if the current thread is blocked on an incomplete
7054 step-over, interrupted by a random signal. */
7055 if (ecs
->event_thread
->control
.trap_expected
7056 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7060 fprintf_unfiltered (gdb_stdlog
,
7061 "infrun: need to finish step-over of [%s]\n",
7062 target_pid_to_str (ecs
->event_thread
->ptid
));
7068 /* Check if the current thread is blocked by a single-step
7069 breakpoint of another thread. */
7070 if (ecs
->hit_singlestep_breakpoint
)
7074 fprintf_unfiltered (gdb_stdlog
,
7075 "infrun: need to step [%s] over single-step "
7077 target_pid_to_str (ecs
->ptid
));
7083 /* If this thread needs yet another step-over (e.g., stepping
7084 through a delay slot), do it first before moving on to
7086 if (thread_still_needs_step_over (ecs
->event_thread
))
7090 fprintf_unfiltered (gdb_stdlog
,
7091 "infrun: thread [%s] still needs step-over\n",
7092 target_pid_to_str (ecs
->event_thread
->ptid
));
7098 /* If scheduler locking applies even if not stepping, there's no
7099 need to walk over threads. Above we've checked whether the
7100 current thread is stepping. If some other thread not the
7101 event thread is stepping, then it must be that scheduler
7102 locking is not in effect. */
7103 if (schedlock_applies (ecs
->event_thread
))
7106 /* Otherwise, we no longer expect a trap in the current thread.
7107 Clear the trap_expected flag before switching back -- this is
7108 what keep_going does as well, if we call it. */
7109 ecs
->event_thread
->control
.trap_expected
= 0;
7111 /* Likewise, clear the signal if it should not be passed. */
7112 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7113 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7115 /* Do all pending step-overs before actually proceeding with
7117 if (start_step_over ())
7119 prepare_to_wait (ecs
);
7123 /* Look for the stepping/nexting thread. */
7124 stepping_thread
= NULL
;
7126 ALL_NON_EXITED_THREADS (tp
)
7128 /* Ignore threads of processes the caller is not
7131 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
7134 /* When stepping over a breakpoint, we lock all threads
7135 except the one that needs to move past the breakpoint.
7136 If a non-event thread has this set, the "incomplete
7137 step-over" check above should have caught it earlier. */
7138 if (tp
->control
.trap_expected
)
7140 internal_error (__FILE__
, __LINE__
,
7141 "[%s] has inconsistent state: "
7142 "trap_expected=%d\n",
7143 target_pid_to_str (tp
->ptid
),
7144 tp
->control
.trap_expected
);
7147 /* Did we find the stepping thread? */
7148 if (tp
->control
.step_range_end
)
7150 /* Yep. There should only one though. */
7151 gdb_assert (stepping_thread
== NULL
);
7153 /* The event thread is handled at the top, before we
7155 gdb_assert (tp
!= ecs
->event_thread
);
7157 /* If some thread other than the event thread is
7158 stepping, then scheduler locking can't be in effect,
7159 otherwise we wouldn't have resumed the current event
7160 thread in the first place. */
7161 gdb_assert (!schedlock_applies (tp
));
7163 stepping_thread
= tp
;
7167 if (stepping_thread
!= NULL
)
7170 fprintf_unfiltered (gdb_stdlog
,
7171 "infrun: switching back to stepped thread\n");
7173 if (keep_going_stepped_thread (stepping_thread
))
7175 prepare_to_wait (ecs
);
7184 /* Set a previously stepped thread back to stepping. Returns true on
7185 success, false if the resume is not possible (e.g., the thread
7189 keep_going_stepped_thread (struct thread_info
*tp
)
7191 struct frame_info
*frame
;
7192 struct execution_control_state ecss
;
7193 struct execution_control_state
*ecs
= &ecss
;
7195 /* If the stepping thread exited, then don't try to switch back and
7196 resume it, which could fail in several different ways depending
7197 on the target. Instead, just keep going.
7199 We can find a stepping dead thread in the thread list in two
7202 - The target supports thread exit events, and when the target
7203 tries to delete the thread from the thread list, inferior_ptid
7204 pointed at the exiting thread. In such case, calling
7205 delete_thread does not really remove the thread from the list;
7206 instead, the thread is left listed, with 'exited' state.
7208 - The target's debug interface does not support thread exit
7209 events, and so we have no idea whatsoever if the previously
7210 stepping thread is still alive. For that reason, we need to
7211 synchronously query the target now. */
7213 if (is_exited (tp
->ptid
)
7214 || !target_thread_alive (tp
->ptid
))
7217 fprintf_unfiltered (gdb_stdlog
,
7218 "infrun: not resuming previously "
7219 "stepped thread, it has vanished\n");
7221 delete_thread (tp
->ptid
);
7226 fprintf_unfiltered (gdb_stdlog
,
7227 "infrun: resuming previously stepped thread\n");
7229 reset_ecs (ecs
, tp
);
7230 switch_to_thread (tp
->ptid
);
7232 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7233 frame
= get_current_frame ();
7235 /* If the PC of the thread we were trying to single-step has
7236 changed, then that thread has trapped or been signaled, but the
7237 event has not been reported to GDB yet. Re-poll the target
7238 looking for this particular thread's event (i.e. temporarily
7239 enable schedlock) by:
7241 - setting a break at the current PC
7242 - resuming that particular thread, only (by setting trap
7245 This prevents us continuously moving the single-step breakpoint
7246 forward, one instruction at a time, overstepping. */
7248 if (stop_pc
!= tp
->prev_pc
)
7253 fprintf_unfiltered (gdb_stdlog
,
7254 "infrun: expected thread advanced also (%s -> %s)\n",
7255 paddress (target_gdbarch (), tp
->prev_pc
),
7256 paddress (target_gdbarch (), stop_pc
));
7258 /* Clear the info of the previous step-over, as it's no longer
7259 valid (if the thread was trying to step over a breakpoint, it
7260 has already succeeded). It's what keep_going would do too,
7261 if we called it. Do this before trying to insert the sss
7262 breakpoint, otherwise if we were previously trying to step
7263 over this exact address in another thread, the breakpoint is
7265 clear_step_over_info ();
7266 tp
->control
.trap_expected
= 0;
7268 insert_single_step_breakpoint (get_frame_arch (frame
),
7269 get_frame_address_space (frame
),
7273 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7274 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7279 fprintf_unfiltered (gdb_stdlog
,
7280 "infrun: expected thread still hasn't advanced\n");
7282 keep_going_pass_signal (ecs
);
7287 /* Is thread TP in the middle of (software or hardware)
7288 single-stepping? (Note the result of this function must never be
7289 passed directly as target_resume's STEP parameter.) */
7292 currently_stepping (struct thread_info
*tp
)
7294 return ((tp
->control
.step_range_end
7295 && tp
->control
.step_resume_breakpoint
== NULL
)
7296 || tp
->control
.trap_expected
7297 || tp
->stepped_breakpoint
7298 || bpstat_should_step ());
7301 /* Inferior has stepped into a subroutine call with source code that
7302 we should not step over. Do step to the first line of code in
7306 handle_step_into_function (struct gdbarch
*gdbarch
,
7307 struct execution_control_state
*ecs
)
7309 struct compunit_symtab
*cust
;
7310 struct symtab_and_line stop_func_sal
, sr_sal
;
7312 fill_in_stop_func (gdbarch
, ecs
);
7314 cust
= find_pc_compunit_symtab (stop_pc
);
7315 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7316 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7317 ecs
->stop_func_start
);
7319 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7320 /* Use the step_resume_break to step until the end of the prologue,
7321 even if that involves jumps (as it seems to on the vax under
7323 /* If the prologue ends in the middle of a source line, continue to
7324 the end of that source line (if it is still within the function).
7325 Otherwise, just go to end of prologue. */
7326 if (stop_func_sal
.end
7327 && stop_func_sal
.pc
!= ecs
->stop_func_start
7328 && stop_func_sal
.end
< ecs
->stop_func_end
)
7329 ecs
->stop_func_start
= stop_func_sal
.end
;
7331 /* Architectures which require breakpoint adjustment might not be able
7332 to place a breakpoint at the computed address. If so, the test
7333 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7334 ecs->stop_func_start to an address at which a breakpoint may be
7335 legitimately placed.
7337 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7338 made, GDB will enter an infinite loop when stepping through
7339 optimized code consisting of VLIW instructions which contain
7340 subinstructions corresponding to different source lines. On
7341 FR-V, it's not permitted to place a breakpoint on any but the
7342 first subinstruction of a VLIW instruction. When a breakpoint is
7343 set, GDB will adjust the breakpoint address to the beginning of
7344 the VLIW instruction. Thus, we need to make the corresponding
7345 adjustment here when computing the stop address. */
7347 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7349 ecs
->stop_func_start
7350 = gdbarch_adjust_breakpoint_address (gdbarch
,
7351 ecs
->stop_func_start
);
7354 if (ecs
->stop_func_start
== stop_pc
)
7356 /* We are already there: stop now. */
7357 end_stepping_range (ecs
);
7362 /* Put the step-breakpoint there and go until there. */
7363 init_sal (&sr_sal
); /* initialize to zeroes */
7364 sr_sal
.pc
= ecs
->stop_func_start
;
7365 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7366 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7368 /* Do not specify what the fp should be when we stop since on
7369 some machines the prologue is where the new fp value is
7371 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7373 /* And make sure stepping stops right away then. */
7374 ecs
->event_thread
->control
.step_range_end
7375 = ecs
->event_thread
->control
.step_range_start
;
7380 /* Inferior has stepped backward into a subroutine call with source
7381 code that we should not step over. Do step to the beginning of the
7382 last line of code in it. */
7385 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7386 struct execution_control_state
*ecs
)
7388 struct compunit_symtab
*cust
;
7389 struct symtab_and_line stop_func_sal
;
7391 fill_in_stop_func (gdbarch
, ecs
);
7393 cust
= find_pc_compunit_symtab (stop_pc
);
7394 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7395 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7396 ecs
->stop_func_start
);
7398 stop_func_sal
= find_pc_line (stop_pc
, 0);
7400 /* OK, we're just going to keep stepping here. */
7401 if (stop_func_sal
.pc
== stop_pc
)
7403 /* We're there already. Just stop stepping now. */
7404 end_stepping_range (ecs
);
7408 /* Else just reset the step range and keep going.
7409 No step-resume breakpoint, they don't work for
7410 epilogues, which can have multiple entry paths. */
7411 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7412 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7418 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7419 This is used to both functions and to skip over code. */
7422 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7423 struct symtab_and_line sr_sal
,
7424 struct frame_id sr_id
,
7425 enum bptype sr_type
)
7427 /* There should never be more than one step-resume or longjmp-resume
7428 breakpoint per thread, so we should never be setting a new
7429 step_resume_breakpoint when one is already active. */
7430 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7431 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7434 fprintf_unfiltered (gdb_stdlog
,
7435 "infrun: inserting step-resume breakpoint at %s\n",
7436 paddress (gdbarch
, sr_sal
.pc
));
7438 inferior_thread ()->control
.step_resume_breakpoint
7439 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7443 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7444 struct symtab_and_line sr_sal
,
7445 struct frame_id sr_id
)
7447 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7452 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7453 This is used to skip a potential signal handler.
7455 This is called with the interrupted function's frame. The signal
7456 handler, when it returns, will resume the interrupted function at
7460 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7462 struct symtab_and_line sr_sal
;
7463 struct gdbarch
*gdbarch
;
7465 gdb_assert (return_frame
!= NULL
);
7466 init_sal (&sr_sal
); /* initialize to zeros */
7468 gdbarch
= get_frame_arch (return_frame
);
7469 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7470 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7471 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7473 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7474 get_stack_frame_id (return_frame
),
7478 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7479 is used to skip a function after stepping into it (for "next" or if
7480 the called function has no debugging information).
7482 The current function has almost always been reached by single
7483 stepping a call or return instruction. NEXT_FRAME belongs to the
7484 current function, and the breakpoint will be set at the caller's
7487 This is a separate function rather than reusing
7488 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7489 get_prev_frame, which may stop prematurely (see the implementation
7490 of frame_unwind_caller_id for an example). */
7493 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7495 struct symtab_and_line sr_sal
;
7496 struct gdbarch
*gdbarch
;
7498 /* We shouldn't have gotten here if we don't know where the call site
7500 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7502 init_sal (&sr_sal
); /* initialize to zeros */
7504 gdbarch
= frame_unwind_caller_arch (next_frame
);
7505 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7506 frame_unwind_caller_pc (next_frame
));
7507 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7508 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7510 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7511 frame_unwind_caller_id (next_frame
));
7514 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7515 new breakpoint at the target of a jmp_buf. The handling of
7516 longjmp-resume uses the same mechanisms used for handling
7517 "step-resume" breakpoints. */
7520 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7522 /* There should never be more than one longjmp-resume breakpoint per
7523 thread, so we should never be setting a new
7524 longjmp_resume_breakpoint when one is already active. */
7525 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7528 fprintf_unfiltered (gdb_stdlog
,
7529 "infrun: inserting longjmp-resume breakpoint at %s\n",
7530 paddress (gdbarch
, pc
));
7532 inferior_thread ()->control
.exception_resume_breakpoint
=
7533 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7536 /* Insert an exception resume breakpoint. TP is the thread throwing
7537 the exception. The block B is the block of the unwinder debug hook
7538 function. FRAME is the frame corresponding to the call to this
7539 function. SYM is the symbol of the function argument holding the
7540 target PC of the exception. */
7543 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7544 const struct block
*b
,
7545 struct frame_info
*frame
,
7550 struct block_symbol vsym
;
7551 struct value
*value
;
7553 struct breakpoint
*bp
;
7555 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
7556 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7557 /* If the value was optimized out, revert to the old behavior. */
7558 if (! value_optimized_out (value
))
7560 handler
= value_as_address (value
);
7563 fprintf_unfiltered (gdb_stdlog
,
7564 "infrun: exception resume at %lx\n",
7565 (unsigned long) handler
);
7567 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7568 handler
, bp_exception_resume
);
7570 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7573 bp
->thread
= tp
->global_num
;
7574 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7577 CATCH (e
, RETURN_MASK_ERROR
)
7579 /* We want to ignore errors here. */
7584 /* A helper for check_exception_resume that sets an
7585 exception-breakpoint based on a SystemTap probe. */
7588 insert_exception_resume_from_probe (struct thread_info
*tp
,
7589 const struct bound_probe
*probe
,
7590 struct frame_info
*frame
)
7592 struct value
*arg_value
;
7594 struct breakpoint
*bp
;
7596 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7600 handler
= value_as_address (arg_value
);
7603 fprintf_unfiltered (gdb_stdlog
,
7604 "infrun: exception resume at %s\n",
7605 paddress (get_objfile_arch (probe
->objfile
),
7608 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7609 handler
, bp_exception_resume
);
7610 bp
->thread
= tp
->global_num
;
7611 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7614 /* This is called when an exception has been intercepted. Check to
7615 see whether the exception's destination is of interest, and if so,
7616 set an exception resume breakpoint there. */
7619 check_exception_resume (struct execution_control_state
*ecs
,
7620 struct frame_info
*frame
)
7622 struct bound_probe probe
;
7623 struct symbol
*func
;
7625 /* First see if this exception unwinding breakpoint was set via a
7626 SystemTap probe point. If so, the probe has two arguments: the
7627 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7628 set a breakpoint there. */
7629 probe
= find_probe_by_pc (get_frame_pc (frame
));
7632 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7636 func
= get_frame_function (frame
);
7642 const struct block
*b
;
7643 struct block_iterator iter
;
7647 /* The exception breakpoint is a thread-specific breakpoint on
7648 the unwinder's debug hook, declared as:
7650 void _Unwind_DebugHook (void *cfa, void *handler);
7652 The CFA argument indicates the frame to which control is
7653 about to be transferred. HANDLER is the destination PC.
7655 We ignore the CFA and set a temporary breakpoint at HANDLER.
7656 This is not extremely efficient but it avoids issues in gdb
7657 with computing the DWARF CFA, and it also works even in weird
7658 cases such as throwing an exception from inside a signal
7661 b
= SYMBOL_BLOCK_VALUE (func
);
7662 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7664 if (!SYMBOL_IS_ARGUMENT (sym
))
7671 insert_exception_resume_breakpoint (ecs
->event_thread
,
7677 CATCH (e
, RETURN_MASK_ERROR
)
7684 stop_waiting (struct execution_control_state
*ecs
)
7687 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7689 /* Let callers know we don't want to wait for the inferior anymore. */
7690 ecs
->wait_some_more
= 0;
7692 /* If all-stop, but the target is always in non-stop mode, stop all
7693 threads now that we're presenting the stop to the user. */
7694 if (!non_stop
&& target_is_non_stop_p ())
7695 stop_all_threads ();
7698 /* Like keep_going, but passes the signal to the inferior, even if the
7699 signal is set to nopass. */
7702 keep_going_pass_signal (struct execution_control_state
*ecs
)
7704 /* Make sure normal_stop is called if we get a QUIT handled before
7706 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
7708 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7709 gdb_assert (!ecs
->event_thread
->resumed
);
7711 /* Save the pc before execution, to compare with pc after stop. */
7712 ecs
->event_thread
->prev_pc
7713 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7715 if (ecs
->event_thread
->control
.trap_expected
)
7717 struct thread_info
*tp
= ecs
->event_thread
;
7720 fprintf_unfiltered (gdb_stdlog
,
7721 "infrun: %s has trap_expected set, "
7722 "resuming to collect trap\n",
7723 target_pid_to_str (tp
->ptid
));
7725 /* We haven't yet gotten our trap, and either: intercepted a
7726 non-signal event (e.g., a fork); or took a signal which we
7727 are supposed to pass through to the inferior. Simply
7729 discard_cleanups (old_cleanups
);
7730 resume (ecs
->event_thread
->suspend
.stop_signal
);
7732 else if (step_over_info_valid_p ())
7734 /* Another thread is stepping over a breakpoint in-line. If
7735 this thread needs a step-over too, queue the request. In
7736 either case, this resume must be deferred for later. */
7737 struct thread_info
*tp
= ecs
->event_thread
;
7739 if (ecs
->hit_singlestep_breakpoint
7740 || thread_still_needs_step_over (tp
))
7743 fprintf_unfiltered (gdb_stdlog
,
7744 "infrun: step-over already in progress: "
7745 "step-over for %s deferred\n",
7746 target_pid_to_str (tp
->ptid
));
7747 thread_step_over_chain_enqueue (tp
);
7752 fprintf_unfiltered (gdb_stdlog
,
7753 "infrun: step-over in progress: "
7754 "resume of %s deferred\n",
7755 target_pid_to_str (tp
->ptid
));
7758 discard_cleanups (old_cleanups
);
7762 struct regcache
*regcache
= get_current_regcache ();
7765 step_over_what step_what
;
7767 /* Either the trap was not expected, but we are continuing
7768 anyway (if we got a signal, the user asked it be passed to
7771 We got our expected trap, but decided we should resume from
7774 We're going to run this baby now!
7776 Note that insert_breakpoints won't try to re-insert
7777 already inserted breakpoints. Therefore, we don't
7778 care if breakpoints were already inserted, or not. */
7780 /* If we need to step over a breakpoint, and we're not using
7781 displaced stepping to do so, insert all breakpoints
7782 (watchpoints, etc.) but the one we're stepping over, step one
7783 instruction, and then re-insert the breakpoint when that step
7786 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7788 remove_bp
= (ecs
->hit_singlestep_breakpoint
7789 || (step_what
& STEP_OVER_BREAKPOINT
));
7790 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7792 /* We can't use displaced stepping if we need to step past a
7793 watchpoint. The instruction copied to the scratch pad would
7794 still trigger the watchpoint. */
7796 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7798 set_step_over_info (get_regcache_aspace (regcache
),
7799 regcache_read_pc (regcache
), remove_wps
,
7800 ecs
->event_thread
->global_num
);
7802 else if (remove_wps
)
7803 set_step_over_info (NULL
, 0, remove_wps
, -1);
7805 /* If we now need to do an in-line step-over, we need to stop
7806 all other threads. Note this must be done before
7807 insert_breakpoints below, because that removes the breakpoint
7808 we're about to step over, otherwise other threads could miss
7810 if (step_over_info_valid_p () && target_is_non_stop_p ())
7811 stop_all_threads ();
7813 /* Stop stepping if inserting breakpoints fails. */
7816 insert_breakpoints ();
7818 CATCH (e
, RETURN_MASK_ERROR
)
7820 exception_print (gdb_stderr
, e
);
7822 discard_cleanups (old_cleanups
);
7827 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7829 discard_cleanups (old_cleanups
);
7830 resume (ecs
->event_thread
->suspend
.stop_signal
);
7833 prepare_to_wait (ecs
);
7836 /* Called when we should continue running the inferior, because the
7837 current event doesn't cause a user visible stop. This does the
7838 resuming part; waiting for the next event is done elsewhere. */
7841 keep_going (struct execution_control_state
*ecs
)
7843 if (ecs
->event_thread
->control
.trap_expected
7844 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7845 ecs
->event_thread
->control
.trap_expected
= 0;
7847 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7848 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7849 keep_going_pass_signal (ecs
);
7852 /* This function normally comes after a resume, before
7853 handle_inferior_event exits. It takes care of any last bits of
7854 housekeeping, and sets the all-important wait_some_more flag. */
7857 prepare_to_wait (struct execution_control_state
*ecs
)
7860 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7862 ecs
->wait_some_more
= 1;
7864 if (!target_is_async_p ())
7865 mark_infrun_async_event_handler ();
7868 /* We are done with the step range of a step/next/si/ni command.
7869 Called once for each n of a "step n" operation. */
7872 end_stepping_range (struct execution_control_state
*ecs
)
7874 ecs
->event_thread
->control
.stop_step
= 1;
7878 /* Several print_*_reason functions to print why the inferior has stopped.
7879 We always print something when the inferior exits, or receives a signal.
7880 The rest of the cases are dealt with later on in normal_stop and
7881 print_it_typical. Ideally there should be a call to one of these
7882 print_*_reason functions functions from handle_inferior_event each time
7883 stop_waiting is called.
7885 Note that we don't call these directly, instead we delegate that to
7886 the interpreters, through observers. Interpreters then call these
7887 with whatever uiout is right. */
7890 print_end_stepping_range_reason (struct ui_out
*uiout
)
7892 /* For CLI-like interpreters, print nothing. */
7894 if (uiout
->is_mi_like_p ())
7896 uiout
->field_string ("reason",
7897 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7902 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7904 annotate_signalled ();
7905 if (uiout
->is_mi_like_p ())
7907 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7908 uiout
->text ("\nProgram terminated with signal ");
7909 annotate_signal_name ();
7910 uiout
->field_string ("signal-name",
7911 gdb_signal_to_name (siggnal
));
7912 annotate_signal_name_end ();
7914 annotate_signal_string ();
7915 uiout
->field_string ("signal-meaning",
7916 gdb_signal_to_string (siggnal
));
7917 annotate_signal_string_end ();
7918 uiout
->text (".\n");
7919 uiout
->text ("The program no longer exists.\n");
7923 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7925 struct inferior
*inf
= current_inferior ();
7926 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7928 annotate_exited (exitstatus
);
7931 if (uiout
->is_mi_like_p ())
7932 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
7933 uiout
->text ("[Inferior ");
7934 uiout
->text (plongest (inf
->num
));
7936 uiout
->text (pidstr
);
7937 uiout
->text (") exited with code ");
7938 uiout
->field_fmt ("exit-code", "0%o", (unsigned int) exitstatus
);
7939 uiout
->text ("]\n");
7943 if (uiout
->is_mi_like_p ())
7945 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7946 uiout
->text ("[Inferior ");
7947 uiout
->text (plongest (inf
->num
));
7949 uiout
->text (pidstr
);
7950 uiout
->text (") exited normally]\n");
7954 /* Some targets/architectures can do extra processing/display of
7955 segmentation faults. E.g., Intel MPX boundary faults.
7956 Call the architecture dependent function to handle the fault. */
7959 handle_segmentation_fault (struct ui_out
*uiout
)
7961 struct regcache
*regcache
= get_current_regcache ();
7962 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7964 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7965 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7969 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7971 struct thread_info
*thr
= inferior_thread ();
7975 if (uiout
->is_mi_like_p ())
7977 else if (show_thread_that_caused_stop ())
7981 uiout
->text ("\nThread ");
7982 uiout
->field_fmt ("thread-id", "%s", print_thread_id (thr
));
7984 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7987 uiout
->text (" \"");
7988 uiout
->field_fmt ("name", "%s", name
);
7993 uiout
->text ("\nProgram");
7995 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
7996 uiout
->text (" stopped");
7999 uiout
->text (" received signal ");
8000 annotate_signal_name ();
8001 if (uiout
->is_mi_like_p ())
8003 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
8004 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
8005 annotate_signal_name_end ();
8007 annotate_signal_string ();
8008 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
8010 if (siggnal
== GDB_SIGNAL_SEGV
)
8011 handle_segmentation_fault (uiout
);
8013 annotate_signal_string_end ();
8015 uiout
->text (".\n");
8019 print_no_history_reason (struct ui_out
*uiout
)
8021 uiout
->text ("\nNo more reverse-execution history.\n");
8024 /* Print current location without a level number, if we have changed
8025 functions or hit a breakpoint. Print source line if we have one.
8026 bpstat_print contains the logic deciding in detail what to print,
8027 based on the event(s) that just occurred. */
8030 print_stop_location (struct target_waitstatus
*ws
)
8033 enum print_what source_flag
;
8034 int do_frame_printing
= 1;
8035 struct thread_info
*tp
= inferior_thread ();
8037 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8041 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8042 should) carry around the function and does (or should) use
8043 that when doing a frame comparison. */
8044 if (tp
->control
.stop_step
8045 && frame_id_eq (tp
->control
.step_frame_id
,
8046 get_frame_id (get_current_frame ()))
8047 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
8049 /* Finished step, just print source line. */
8050 source_flag
= SRC_LINE
;
8054 /* Print location and source line. */
8055 source_flag
= SRC_AND_LOC
;
8058 case PRINT_SRC_AND_LOC
:
8059 /* Print location and source line. */
8060 source_flag
= SRC_AND_LOC
;
8062 case PRINT_SRC_ONLY
:
8063 source_flag
= SRC_LINE
;
8066 /* Something bogus. */
8067 source_flag
= SRC_LINE
;
8068 do_frame_printing
= 0;
8071 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8074 /* The behavior of this routine with respect to the source
8076 SRC_LINE: Print only source line
8077 LOCATION: Print only location
8078 SRC_AND_LOC: Print location and source line. */
8079 if (do_frame_printing
)
8080 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8086 print_stop_event (struct ui_out
*uiout
)
8088 struct target_waitstatus last
;
8090 struct thread_info
*tp
;
8092 get_last_target_status (&last_ptid
, &last
);
8095 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8097 print_stop_location (&last
);
8099 /* Display the auto-display expressions. */
8103 tp
= inferior_thread ();
8104 if (tp
->thread_fsm
!= NULL
8105 && thread_fsm_finished_p (tp
->thread_fsm
))
8107 struct return_value_info
*rv
;
8109 rv
= thread_fsm_return_value (tp
->thread_fsm
);
8111 print_return_value (uiout
, rv
);
8118 maybe_remove_breakpoints (void)
8120 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
8122 if (remove_breakpoints ())
8124 target_terminal_ours_for_output ();
8125 printf_filtered (_("Cannot remove breakpoints because "
8126 "program is no longer writable.\nFurther "
8127 "execution is probably impossible.\n"));
8132 /* The execution context that just caused a normal stop. */
8139 /* The event PTID. */
8143 /* If stopp for a thread event, this is the thread that caused the
8145 struct thread_info
*thread
;
8147 /* The inferior that caused the stop. */
8151 /* Returns a new stop context. If stopped for a thread event, this
8152 takes a strong reference to the thread. */
8154 static struct stop_context
*
8155 save_stop_context (void)
8157 struct stop_context
*sc
= XNEW (struct stop_context
);
8159 sc
->stop_id
= get_stop_id ();
8160 sc
->ptid
= inferior_ptid
;
8161 sc
->inf_num
= current_inferior ()->num
;
8163 if (!ptid_equal (inferior_ptid
, null_ptid
))
8165 /* Take a strong reference so that the thread can't be deleted
8167 sc
->thread
= inferior_thread ();
8168 sc
->thread
->refcount
++;
8176 /* Release a stop context previously created with save_stop_context.
8177 Releases the strong reference to the thread as well. */
8180 release_stop_context_cleanup (void *arg
)
8182 struct stop_context
*sc
= (struct stop_context
*) arg
;
8184 if (sc
->thread
!= NULL
)
8185 sc
->thread
->refcount
--;
8189 /* Return true if the current context no longer matches the saved stop
8193 stop_context_changed (struct stop_context
*prev
)
8195 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
8197 if (prev
->inf_num
!= current_inferior ()->num
)
8199 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
8201 if (get_stop_id () != prev
->stop_id
)
8211 struct target_waitstatus last
;
8213 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
8216 get_last_target_status (&last_ptid
, &last
);
8220 /* If an exception is thrown from this point on, make sure to
8221 propagate GDB's knowledge of the executing state to the
8222 frontend/user running state. A QUIT is an easy exception to see
8223 here, so do this before any filtered output. */
8225 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
8226 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8227 || last
.kind
== TARGET_WAITKIND_EXITED
)
8229 /* On some targets, we may still have live threads in the
8230 inferior when we get a process exit event. E.g., for
8231 "checkpoint", when the current checkpoint/fork exits,
8232 linux-fork.c automatically switches to another fork from
8233 within target_mourn_inferior. */
8234 if (!ptid_equal (inferior_ptid
, null_ptid
))
8236 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8237 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8240 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8241 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8243 /* As we're presenting a stop, and potentially removing breakpoints,
8244 update the thread list so we can tell whether there are threads
8245 running on the target. With target remote, for example, we can
8246 only learn about new threads when we explicitly update the thread
8247 list. Do this before notifying the interpreters about signal
8248 stops, end of stepping ranges, etc., so that the "new thread"
8249 output is emitted before e.g., "Program received signal FOO",
8250 instead of after. */
8251 update_thread_list ();
8253 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8254 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
8256 /* As with the notification of thread events, we want to delay
8257 notifying the user that we've switched thread context until
8258 the inferior actually stops.
8260 There's no point in saying anything if the inferior has exited.
8261 Note that SIGNALLED here means "exited with a signal", not
8262 "received a signal".
8264 Also skip saying anything in non-stop mode. In that mode, as we
8265 don't want GDB to switch threads behind the user's back, to avoid
8266 races where the user is typing a command to apply to thread x,
8267 but GDB switches to thread y before the user finishes entering
8268 the command, fetch_inferior_event installs a cleanup to restore
8269 the current thread back to the thread the user had selected right
8270 after this event is handled, so we're not really switching, only
8271 informing of a stop. */
8273 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8274 && target_has_execution
8275 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8276 && last
.kind
!= TARGET_WAITKIND_EXITED
8277 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8279 SWITCH_THRU_ALL_UIS ()
8281 target_terminal_ours_for_output ();
8282 printf_filtered (_("[Switching to %s]\n"),
8283 target_pid_to_str (inferior_ptid
));
8284 annotate_thread_changed ();
8286 previous_inferior_ptid
= inferior_ptid
;
8289 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8291 SWITCH_THRU_ALL_UIS ()
8292 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8294 target_terminal_ours_for_output ();
8295 printf_filtered (_("No unwaited-for children left.\n"));
8299 /* Note: this depends on the update_thread_list call above. */
8300 maybe_remove_breakpoints ();
8302 /* If an auto-display called a function and that got a signal,
8303 delete that auto-display to avoid an infinite recursion. */
8305 if (stopped_by_random_signal
)
8306 disable_current_display ();
8308 SWITCH_THRU_ALL_UIS ()
8310 async_enable_stdin ();
8313 /* Let the user/frontend see the threads as stopped. */
8314 do_cleanups (old_chain
);
8316 /* Select innermost stack frame - i.e., current frame is frame 0,
8317 and current location is based on that. Handle the case where the
8318 dummy call is returning after being stopped. E.g. the dummy call
8319 previously hit a breakpoint. (If the dummy call returns
8320 normally, we won't reach here.) Do this before the stop hook is
8321 run, so that it doesn't get to see the temporary dummy frame,
8322 which is not where we'll present the stop. */
8323 if (has_stack_frames ())
8325 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8327 /* Pop the empty frame that contains the stack dummy. This
8328 also restores inferior state prior to the call (struct
8329 infcall_suspend_state). */
8330 struct frame_info
*frame
= get_current_frame ();
8332 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8334 /* frame_pop calls reinit_frame_cache as the last thing it
8335 does which means there's now no selected frame. */
8338 select_frame (get_current_frame ());
8340 /* Set the current source location. */
8341 set_current_sal_from_frame (get_current_frame ());
8344 /* Look up the hook_stop and run it (CLI internally handles problem
8345 of stop_command's pre-hook not existing). */
8346 if (stop_command
!= NULL
)
8348 struct stop_context
*saved_context
= save_stop_context ();
8349 struct cleanup
*old_chain
8350 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8352 catch_errors (hook_stop_stub
, stop_command
,
8353 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
8355 /* If the stop hook resumes the target, then there's no point in
8356 trying to notify about the previous stop; its context is
8357 gone. Likewise if the command switches thread or inferior --
8358 the observers would print a stop for the wrong
8360 if (stop_context_changed (saved_context
))
8362 do_cleanups (old_chain
);
8365 do_cleanups (old_chain
);
8368 /* Notify observers about the stop. This is where the interpreters
8369 print the stop event. */
8370 if (!ptid_equal (inferior_ptid
, null_ptid
))
8371 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
8374 observer_notify_normal_stop (NULL
, stop_print_frame
);
8376 annotate_stopped ();
8378 if (target_has_execution
)
8380 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8381 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8382 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8383 Delete any breakpoint that is to be deleted at the next stop. */
8384 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8387 /* Try to get rid of automatically added inferiors that are no
8388 longer needed. Keeping those around slows down things linearly.
8389 Note that this never removes the current inferior. */
8396 hook_stop_stub (void *cmd
)
8398 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
8403 signal_stop_state (int signo
)
8405 return signal_stop
[signo
];
8409 signal_print_state (int signo
)
8411 return signal_print
[signo
];
8415 signal_pass_state (int signo
)
8417 return signal_program
[signo
];
8421 signal_cache_update (int signo
)
8425 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8426 signal_cache_update (signo
);
8431 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8432 && signal_print
[signo
] == 0
8433 && signal_program
[signo
] == 1
8434 && signal_catch
[signo
] == 0);
8438 signal_stop_update (int signo
, int state
)
8440 int ret
= signal_stop
[signo
];
8442 signal_stop
[signo
] = state
;
8443 signal_cache_update (signo
);
8448 signal_print_update (int signo
, int state
)
8450 int ret
= signal_print
[signo
];
8452 signal_print
[signo
] = state
;
8453 signal_cache_update (signo
);
8458 signal_pass_update (int signo
, int state
)
8460 int ret
= signal_program
[signo
];
8462 signal_program
[signo
] = state
;
8463 signal_cache_update (signo
);
8467 /* Update the global 'signal_catch' from INFO and notify the
8471 signal_catch_update (const unsigned int *info
)
8475 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8476 signal_catch
[i
] = info
[i
] > 0;
8477 signal_cache_update (-1);
8478 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8482 sig_print_header (void)
8484 printf_filtered (_("Signal Stop\tPrint\tPass "
8485 "to program\tDescription\n"));
8489 sig_print_info (enum gdb_signal oursig
)
8491 const char *name
= gdb_signal_to_name (oursig
);
8492 int name_padding
= 13 - strlen (name
);
8494 if (name_padding
<= 0)
8497 printf_filtered ("%s", name
);
8498 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8499 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8500 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8501 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8502 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8505 /* Specify how various signals in the inferior should be handled. */
8508 handle_command (char *args
, int from_tty
)
8511 int digits
, wordlen
;
8512 int sigfirst
, signum
, siglast
;
8513 enum gdb_signal oursig
;
8516 unsigned char *sigs
;
8517 struct cleanup
*old_chain
;
8521 error_no_arg (_("signal to handle"));
8524 /* Allocate and zero an array of flags for which signals to handle. */
8526 nsigs
= (int) GDB_SIGNAL_LAST
;
8527 sigs
= (unsigned char *) alloca (nsigs
);
8528 memset (sigs
, 0, nsigs
);
8530 /* Break the command line up into args. */
8532 argv
= gdb_buildargv (args
);
8533 old_chain
= make_cleanup_freeargv (argv
);
8535 /* Walk through the args, looking for signal oursigs, signal names, and
8536 actions. Signal numbers and signal names may be interspersed with
8537 actions, with the actions being performed for all signals cumulatively
8538 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8540 while (*argv
!= NULL
)
8542 wordlen
= strlen (*argv
);
8543 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
8547 sigfirst
= siglast
= -1;
8549 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
8551 /* Apply action to all signals except those used by the
8552 debugger. Silently skip those. */
8555 siglast
= nsigs
- 1;
8557 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
8559 SET_SIGS (nsigs
, sigs
, signal_stop
);
8560 SET_SIGS (nsigs
, sigs
, signal_print
);
8562 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
8564 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8566 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
8568 SET_SIGS (nsigs
, sigs
, signal_print
);
8570 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
8572 SET_SIGS (nsigs
, sigs
, signal_program
);
8574 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
8576 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8578 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
8580 SET_SIGS (nsigs
, sigs
, signal_program
);
8582 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
8584 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8585 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8587 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
8589 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8591 else if (digits
> 0)
8593 /* It is numeric. The numeric signal refers to our own
8594 internal signal numbering from target.h, not to host/target
8595 signal number. This is a feature; users really should be
8596 using symbolic names anyway, and the common ones like
8597 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8599 sigfirst
= siglast
= (int)
8600 gdb_signal_from_command (atoi (*argv
));
8601 if ((*argv
)[digits
] == '-')
8604 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
8606 if (sigfirst
> siglast
)
8608 /* Bet he didn't figure we'd think of this case... */
8616 oursig
= gdb_signal_from_name (*argv
);
8617 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8619 sigfirst
= siglast
= (int) oursig
;
8623 /* Not a number and not a recognized flag word => complain. */
8624 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
8628 /* If any signal numbers or symbol names were found, set flags for
8629 which signals to apply actions to. */
8631 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8633 switch ((enum gdb_signal
) signum
)
8635 case GDB_SIGNAL_TRAP
:
8636 case GDB_SIGNAL_INT
:
8637 if (!allsigs
&& !sigs
[signum
])
8639 if (query (_("%s is used by the debugger.\n\
8640 Are you sure you want to change it? "),
8641 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8647 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8648 gdb_flush (gdb_stdout
);
8653 case GDB_SIGNAL_DEFAULT
:
8654 case GDB_SIGNAL_UNKNOWN
:
8655 /* Make sure that "all" doesn't print these. */
8666 for (signum
= 0; signum
< nsigs
; signum
++)
8669 signal_cache_update (-1);
8670 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8671 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8675 /* Show the results. */
8676 sig_print_header ();
8677 for (; signum
< nsigs
; signum
++)
8679 sig_print_info ((enum gdb_signal
) signum
);
8685 do_cleanups (old_chain
);
8688 /* Complete the "handle" command. */
8690 static VEC (char_ptr
) *
8691 handle_completer (struct cmd_list_element
*ignore
,
8692 const char *text
, const char *word
)
8694 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
8695 static const char * const keywords
[] =
8709 vec_signals
= signal_completer (ignore
, text
, word
);
8710 vec_keywords
= complete_on_enum (keywords
, word
, word
);
8712 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
8713 VEC_free (char_ptr
, vec_signals
);
8714 VEC_free (char_ptr
, vec_keywords
);
8719 gdb_signal_from_command (int num
)
8721 if (num
>= 1 && num
<= 15)
8722 return (enum gdb_signal
) num
;
8723 error (_("Only signals 1-15 are valid as numeric signals.\n\
8724 Use \"info signals\" for a list of symbolic signals."));
8727 /* Print current contents of the tables set by the handle command.
8728 It is possible we should just be printing signals actually used
8729 by the current target (but for things to work right when switching
8730 targets, all signals should be in the signal tables). */
8733 signals_info (char *signum_exp
, int from_tty
)
8735 enum gdb_signal oursig
;
8737 sig_print_header ();
8741 /* First see if this is a symbol name. */
8742 oursig
= gdb_signal_from_name (signum_exp
);
8743 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8745 /* No, try numeric. */
8747 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8749 sig_print_info (oursig
);
8753 printf_filtered ("\n");
8754 /* These ugly casts brought to you by the native VAX compiler. */
8755 for (oursig
= GDB_SIGNAL_FIRST
;
8756 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8757 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8761 if (oursig
!= GDB_SIGNAL_UNKNOWN
8762 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8763 sig_print_info (oursig
);
8766 printf_filtered (_("\nUse the \"handle\" command "
8767 "to change these tables.\n"));
8770 /* The $_siginfo convenience variable is a bit special. We don't know
8771 for sure the type of the value until we actually have a chance to
8772 fetch the data. The type can change depending on gdbarch, so it is
8773 also dependent on which thread you have selected.
8775 1. making $_siginfo be an internalvar that creates a new value on
8778 2. making the value of $_siginfo be an lval_computed value. */
8780 /* This function implements the lval_computed support for reading a
8784 siginfo_value_read (struct value
*v
)
8786 LONGEST transferred
;
8788 /* If we can access registers, so can we access $_siginfo. Likewise
8790 validate_registers_access ();
8793 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8795 value_contents_all_raw (v
),
8797 TYPE_LENGTH (value_type (v
)));
8799 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8800 error (_("Unable to read siginfo"));
8803 /* This function implements the lval_computed support for writing a
8807 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8809 LONGEST transferred
;
8811 /* If we can access registers, so can we access $_siginfo. Likewise
8813 validate_registers_access ();
8815 transferred
= target_write (¤t_target
,
8816 TARGET_OBJECT_SIGNAL_INFO
,
8818 value_contents_all_raw (fromval
),
8820 TYPE_LENGTH (value_type (fromval
)));
8822 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8823 error (_("Unable to write siginfo"));
8826 static const struct lval_funcs siginfo_value_funcs
=
8832 /* Return a new value with the correct type for the siginfo object of
8833 the current thread using architecture GDBARCH. Return a void value
8834 if there's no object available. */
8836 static struct value
*
8837 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8840 if (target_has_stack
8841 && !ptid_equal (inferior_ptid
, null_ptid
)
8842 && gdbarch_get_siginfo_type_p (gdbarch
))
8844 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8846 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8849 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8853 /* infcall_suspend_state contains state about the program itself like its
8854 registers and any signal it received when it last stopped.
8855 This state must be restored regardless of how the inferior function call
8856 ends (either successfully, or after it hits a breakpoint or signal)
8857 if the program is to properly continue where it left off. */
8859 struct infcall_suspend_state
8861 struct thread_suspend_state thread_suspend
;
8865 struct regcache
*registers
;
8867 /* Format of SIGINFO_DATA or NULL if it is not present. */
8868 struct gdbarch
*siginfo_gdbarch
;
8870 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8871 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8872 content would be invalid. */
8873 gdb_byte
*siginfo_data
;
8876 struct infcall_suspend_state
*
8877 save_infcall_suspend_state (void)
8879 struct infcall_suspend_state
*inf_state
;
8880 struct thread_info
*tp
= inferior_thread ();
8881 struct regcache
*regcache
= get_current_regcache ();
8882 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8883 gdb_byte
*siginfo_data
= NULL
;
8885 if (gdbarch_get_siginfo_type_p (gdbarch
))
8887 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8888 size_t len
= TYPE_LENGTH (type
);
8889 struct cleanup
*back_to
;
8891 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8892 back_to
= make_cleanup (xfree
, siginfo_data
);
8894 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8895 siginfo_data
, 0, len
) == len
)
8896 discard_cleanups (back_to
);
8899 /* Errors ignored. */
8900 do_cleanups (back_to
);
8901 siginfo_data
= NULL
;
8905 inf_state
= XCNEW (struct infcall_suspend_state
);
8909 inf_state
->siginfo_gdbarch
= gdbarch
;
8910 inf_state
->siginfo_data
= siginfo_data
;
8913 inf_state
->thread_suspend
= tp
->suspend
;
8915 /* run_inferior_call will not use the signal due to its `proceed' call with
8916 GDB_SIGNAL_0 anyway. */
8917 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8919 inf_state
->stop_pc
= stop_pc
;
8921 inf_state
->registers
= regcache_dup (regcache
);
8926 /* Restore inferior session state to INF_STATE. */
8929 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8931 struct thread_info
*tp
= inferior_thread ();
8932 struct regcache
*regcache
= get_current_regcache ();
8933 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8935 tp
->suspend
= inf_state
->thread_suspend
;
8937 stop_pc
= inf_state
->stop_pc
;
8939 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8941 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8943 /* Errors ignored. */
8944 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8945 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8948 /* The inferior can be gone if the user types "print exit(0)"
8949 (and perhaps other times). */
8950 if (target_has_execution
)
8951 /* NB: The register write goes through to the target. */
8952 regcache_cpy (regcache
, inf_state
->registers
);
8954 discard_infcall_suspend_state (inf_state
);
8958 do_restore_infcall_suspend_state_cleanup (void *state
)
8960 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
8964 make_cleanup_restore_infcall_suspend_state
8965 (struct infcall_suspend_state
*inf_state
)
8967 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8971 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8973 regcache_xfree (inf_state
->registers
);
8974 xfree (inf_state
->siginfo_data
);
8979 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8981 return inf_state
->registers
;
8984 /* infcall_control_state contains state regarding gdb's control of the
8985 inferior itself like stepping control. It also contains session state like
8986 the user's currently selected frame. */
8988 struct infcall_control_state
8990 struct thread_control_state thread_control
;
8991 struct inferior_control_state inferior_control
;
8994 enum stop_stack_kind stop_stack_dummy
;
8995 int stopped_by_random_signal
;
8997 /* ID if the selected frame when the inferior function call was made. */
8998 struct frame_id selected_frame_id
;
9001 /* Save all of the information associated with the inferior<==>gdb
9004 struct infcall_control_state
*
9005 save_infcall_control_state (void)
9007 struct infcall_control_state
*inf_status
=
9008 XNEW (struct infcall_control_state
);
9009 struct thread_info
*tp
= inferior_thread ();
9010 struct inferior
*inf
= current_inferior ();
9012 inf_status
->thread_control
= tp
->control
;
9013 inf_status
->inferior_control
= inf
->control
;
9015 tp
->control
.step_resume_breakpoint
= NULL
;
9016 tp
->control
.exception_resume_breakpoint
= NULL
;
9018 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9019 chain. If caller's caller is walking the chain, they'll be happier if we
9020 hand them back the original chain when restore_infcall_control_state is
9022 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9025 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9026 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9028 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
9034 restore_selected_frame (void *args
)
9036 struct frame_id
*fid
= (struct frame_id
*) args
;
9037 struct frame_info
*frame
;
9039 frame
= frame_find_by_id (*fid
);
9041 /* If inf_status->selected_frame_id is NULL, there was no previously
9045 warning (_("Unable to restore previously selected frame."));
9049 select_frame (frame
);
9054 /* Restore inferior session state to INF_STATUS. */
9057 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9059 struct thread_info
*tp
= inferior_thread ();
9060 struct inferior
*inf
= current_inferior ();
9062 if (tp
->control
.step_resume_breakpoint
)
9063 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9065 if (tp
->control
.exception_resume_breakpoint
)
9066 tp
->control
.exception_resume_breakpoint
->disposition
9067 = disp_del_at_next_stop
;
9069 /* Handle the bpstat_copy of the chain. */
9070 bpstat_clear (&tp
->control
.stop_bpstat
);
9072 tp
->control
= inf_status
->thread_control
;
9073 inf
->control
= inf_status
->inferior_control
;
9076 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9077 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9079 if (target_has_stack
)
9081 /* The point of catch_errors is that if the stack is clobbered,
9082 walking the stack might encounter a garbage pointer and
9083 error() trying to dereference it. */
9085 (restore_selected_frame
, &inf_status
->selected_frame_id
,
9086 "Unable to restore previously selected frame:\n",
9087 RETURN_MASK_ERROR
) == 0)
9088 /* Error in restoring the selected frame. Select the innermost
9090 select_frame (get_current_frame ());
9097 do_restore_infcall_control_state_cleanup (void *sts
)
9099 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
9103 make_cleanup_restore_infcall_control_state
9104 (struct infcall_control_state
*inf_status
)
9106 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
9110 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9112 if (inf_status
->thread_control
.step_resume_breakpoint
)
9113 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9114 = disp_del_at_next_stop
;
9116 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9117 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9118 = disp_del_at_next_stop
;
9120 /* See save_infcall_control_state for info on stop_bpstat. */
9121 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9126 /* restore_inferior_ptid() will be used by the cleanup machinery
9127 to restore the inferior_ptid value saved in a call to
9128 save_inferior_ptid(). */
9131 restore_inferior_ptid (void *arg
)
9133 ptid_t
*saved_ptid_ptr
= (ptid_t
*) arg
;
9135 inferior_ptid
= *saved_ptid_ptr
;
9139 /* Save the value of inferior_ptid so that it may be restored by a
9140 later call to do_cleanups(). Returns the struct cleanup pointer
9141 needed for later doing the cleanup. */
9144 save_inferior_ptid (void)
9146 ptid_t
*saved_ptid_ptr
= XNEW (ptid_t
);
9148 *saved_ptid_ptr
= inferior_ptid
;
9149 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
9155 clear_exit_convenience_vars (void)
9157 clear_internalvar (lookup_internalvar ("_exitsignal"));
9158 clear_internalvar (lookup_internalvar ("_exitcode"));
9162 /* User interface for reverse debugging:
9163 Set exec-direction / show exec-direction commands
9164 (returns error unless target implements to_set_exec_direction method). */
9166 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9167 static const char exec_forward
[] = "forward";
9168 static const char exec_reverse
[] = "reverse";
9169 static const char *exec_direction
= exec_forward
;
9170 static const char *const exec_direction_names
[] = {
9177 set_exec_direction_func (char *args
, int from_tty
,
9178 struct cmd_list_element
*cmd
)
9180 if (target_can_execute_reverse
)
9182 if (!strcmp (exec_direction
, exec_forward
))
9183 execution_direction
= EXEC_FORWARD
;
9184 else if (!strcmp (exec_direction
, exec_reverse
))
9185 execution_direction
= EXEC_REVERSE
;
9189 exec_direction
= exec_forward
;
9190 error (_("Target does not support this operation."));
9195 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9196 struct cmd_list_element
*cmd
, const char *value
)
9198 switch (execution_direction
) {
9200 fprintf_filtered (out
, _("Forward.\n"));
9203 fprintf_filtered (out
, _("Reverse.\n"));
9206 internal_error (__FILE__
, __LINE__
,
9207 _("bogus execution_direction value: %d"),
9208 (int) execution_direction
);
9213 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9214 struct cmd_list_element
*c
, const char *value
)
9216 fprintf_filtered (file
, _("Resuming the execution of threads "
9217 "of all processes is %s.\n"), value
);
9220 /* Implementation of `siginfo' variable. */
9222 static const struct internalvar_funcs siginfo_funcs
=
9229 /* Callback for infrun's target events source. This is marked when a
9230 thread has a pending status to process. */
9233 infrun_async_inferior_event_handler (gdb_client_data data
)
9235 inferior_event_handler (INF_REG_EVENT
, NULL
);
9239 _initialize_infrun (void)
9243 struct cmd_list_element
*c
;
9245 /* Register extra event sources in the event loop. */
9246 infrun_async_inferior_event_token
9247 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9249 add_info ("signals", signals_info
, _("\
9250 What debugger does when program gets various signals.\n\
9251 Specify a signal as argument to print info on that signal only."));
9252 add_info_alias ("handle", "signals", 0);
9254 c
= add_com ("handle", class_run
, handle_command
, _("\
9255 Specify how to handle signals.\n\
9256 Usage: handle SIGNAL [ACTIONS]\n\
9257 Args are signals and actions to apply to those signals.\n\
9258 If no actions are specified, the current settings for the specified signals\n\
9259 will be displayed instead.\n\
9261 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9262 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9263 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9264 The special arg \"all\" is recognized to mean all signals except those\n\
9265 used by the debugger, typically SIGTRAP and SIGINT.\n\
9267 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9268 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9269 Stop means reenter debugger if this signal happens (implies print).\n\
9270 Print means print a message if this signal happens.\n\
9271 Pass means let program see this signal; otherwise program doesn't know.\n\
9272 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9273 Pass and Stop may be combined.\n\
9275 Multiple signals may be specified. Signal numbers and signal names\n\
9276 may be interspersed with actions, with the actions being performed for\n\
9277 all signals cumulatively specified."));
9278 set_cmd_completer (c
, handle_completer
);
9281 stop_command
= add_cmd ("stop", class_obscure
,
9282 not_just_help_class_command
, _("\
9283 There is no `stop' command, but you can set a hook on `stop'.\n\
9284 This allows you to set a list of commands to be run each time execution\n\
9285 of the program stops."), &cmdlist
);
9287 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9288 Set inferior debugging."), _("\
9289 Show inferior debugging."), _("\
9290 When non-zero, inferior specific debugging is enabled."),
9293 &setdebuglist
, &showdebuglist
);
9295 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9296 &debug_displaced
, _("\
9297 Set displaced stepping debugging."), _("\
9298 Show displaced stepping debugging."), _("\
9299 When non-zero, displaced stepping specific debugging is enabled."),
9301 show_debug_displaced
,
9302 &setdebuglist
, &showdebuglist
);
9304 add_setshow_boolean_cmd ("non-stop", no_class
,
9306 Set whether gdb controls the inferior in non-stop mode."), _("\
9307 Show whether gdb controls the inferior in non-stop mode."), _("\
9308 When debugging a multi-threaded program and this setting is\n\
9309 off (the default, also called all-stop mode), when one thread stops\n\
9310 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9311 all other threads in the program while you interact with the thread of\n\
9312 interest. When you continue or step a thread, you can allow the other\n\
9313 threads to run, or have them remain stopped, but while you inspect any\n\
9314 thread's state, all threads stop.\n\
9316 In non-stop mode, when one thread stops, other threads can continue\n\
9317 to run freely. You'll be able to step each thread independently,\n\
9318 leave it stopped or free to run as needed."),
9324 numsigs
= (int) GDB_SIGNAL_LAST
;
9325 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9326 signal_print
= XNEWVEC (unsigned char, numsigs
);
9327 signal_program
= XNEWVEC (unsigned char, numsigs
);
9328 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9329 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9330 for (i
= 0; i
< numsigs
; i
++)
9333 signal_print
[i
] = 1;
9334 signal_program
[i
] = 1;
9335 signal_catch
[i
] = 0;
9338 /* Signals caused by debugger's own actions should not be given to
9339 the program afterwards.
9341 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9342 explicitly specifies that it should be delivered to the target
9343 program. Typically, that would occur when a user is debugging a
9344 target monitor on a simulator: the target monitor sets a
9345 breakpoint; the simulator encounters this breakpoint and halts
9346 the simulation handing control to GDB; GDB, noting that the stop
9347 address doesn't map to any known breakpoint, returns control back
9348 to the simulator; the simulator then delivers the hardware
9349 equivalent of a GDB_SIGNAL_TRAP to the program being
9351 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9352 signal_program
[GDB_SIGNAL_INT
] = 0;
9354 /* Signals that are not errors should not normally enter the debugger. */
9355 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9356 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9357 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9358 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9359 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9360 signal_print
[GDB_SIGNAL_PROF
] = 0;
9361 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9362 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9363 signal_stop
[GDB_SIGNAL_IO
] = 0;
9364 signal_print
[GDB_SIGNAL_IO
] = 0;
9365 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9366 signal_print
[GDB_SIGNAL_POLL
] = 0;
9367 signal_stop
[GDB_SIGNAL_URG
] = 0;
9368 signal_print
[GDB_SIGNAL_URG
] = 0;
9369 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9370 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9371 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9372 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9374 /* These signals are used internally by user-level thread
9375 implementations. (See signal(5) on Solaris.) Like the above
9376 signals, a healthy program receives and handles them as part of
9377 its normal operation. */
9378 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9379 signal_print
[GDB_SIGNAL_LWP
] = 0;
9380 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9381 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9382 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9383 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9384 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9385 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9387 /* Update cached state. */
9388 signal_cache_update (-1);
9390 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9391 &stop_on_solib_events
, _("\
9392 Set stopping for shared library events."), _("\
9393 Show stopping for shared library events."), _("\
9394 If nonzero, gdb will give control to the user when the dynamic linker\n\
9395 notifies gdb of shared library events. The most common event of interest\n\
9396 to the user would be loading/unloading of a new library."),
9397 set_stop_on_solib_events
,
9398 show_stop_on_solib_events
,
9399 &setlist
, &showlist
);
9401 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9402 follow_fork_mode_kind_names
,
9403 &follow_fork_mode_string
, _("\
9404 Set debugger response to a program call of fork or vfork."), _("\
9405 Show debugger response to a program call of fork or vfork."), _("\
9406 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9407 parent - the original process is debugged after a fork\n\
9408 child - the new process is debugged after a fork\n\
9409 The unfollowed process will continue to run.\n\
9410 By default, the debugger will follow the parent process."),
9412 show_follow_fork_mode_string
,
9413 &setlist
, &showlist
);
9415 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9416 follow_exec_mode_names
,
9417 &follow_exec_mode_string
, _("\
9418 Set debugger response to a program call of exec."), _("\
9419 Show debugger response to a program call of exec."), _("\
9420 An exec call replaces the program image of a process.\n\
9422 follow-exec-mode can be:\n\
9424 new - the debugger creates a new inferior and rebinds the process\n\
9425 to this new inferior. The program the process was running before\n\
9426 the exec call can be restarted afterwards by restarting the original\n\
9429 same - the debugger keeps the process bound to the same inferior.\n\
9430 The new executable image replaces the previous executable loaded in\n\
9431 the inferior. Restarting the inferior after the exec call restarts\n\
9432 the executable the process was running after the exec call.\n\
9434 By default, the debugger will use the same inferior."),
9436 show_follow_exec_mode_string
,
9437 &setlist
, &showlist
);
9439 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9440 scheduler_enums
, &scheduler_mode
, _("\
9441 Set mode for locking scheduler during execution."), _("\
9442 Show mode for locking scheduler during execution."), _("\
9443 off == no locking (threads may preempt at any time)\n\
9444 on == full locking (no thread except the current thread may run)\n\
9445 This applies to both normal execution and replay mode.\n\
9446 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9447 In this mode, other threads may run during other commands.\n\
9448 This applies to both normal execution and replay mode.\n\
9449 replay == scheduler locked in replay mode and unlocked during normal execution."),
9450 set_schedlock_func
, /* traps on target vector */
9451 show_scheduler_mode
,
9452 &setlist
, &showlist
);
9454 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9455 Set mode for resuming threads of all processes."), _("\
9456 Show mode for resuming threads of all processes."), _("\
9457 When on, execution commands (such as 'continue' or 'next') resume all\n\
9458 threads of all processes. When off (which is the default), execution\n\
9459 commands only resume the threads of the current process. The set of\n\
9460 threads that are resumed is further refined by the scheduler-locking\n\
9461 mode (see help set scheduler-locking)."),
9463 show_schedule_multiple
,
9464 &setlist
, &showlist
);
9466 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9467 Set mode of the step operation."), _("\
9468 Show mode of the step operation."), _("\
9469 When set, doing a step over a function without debug line information\n\
9470 will stop at the first instruction of that function. Otherwise, the\n\
9471 function is skipped and the step command stops at a different source line."),
9473 show_step_stop_if_no_debug
,
9474 &setlist
, &showlist
);
9476 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9477 &can_use_displaced_stepping
, _("\
9478 Set debugger's willingness to use displaced stepping."), _("\
9479 Show debugger's willingness to use displaced stepping."), _("\
9480 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9481 supported by the target architecture. If off, gdb will not use displaced\n\
9482 stepping to step over breakpoints, even if such is supported by the target\n\
9483 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9484 if the target architecture supports it and non-stop mode is active, but will not\n\
9485 use it in all-stop mode (see help set non-stop)."),
9487 show_can_use_displaced_stepping
,
9488 &setlist
, &showlist
);
9490 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9491 &exec_direction
, _("Set direction of execution.\n\
9492 Options are 'forward' or 'reverse'."),
9493 _("Show direction of execution (forward/reverse)."),
9494 _("Tells gdb whether to execute forward or backward."),
9495 set_exec_direction_func
, show_exec_direction_func
,
9496 &setlist
, &showlist
);
9498 /* Set/show detach-on-fork: user-settable mode. */
9500 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9501 Set whether gdb will detach the child of a fork."), _("\
9502 Show whether gdb will detach the child of a fork."), _("\
9503 Tells gdb whether to detach the child of a fork."),
9504 NULL
, NULL
, &setlist
, &showlist
);
9506 /* Set/show disable address space randomization mode. */
9508 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9509 &disable_randomization
, _("\
9510 Set disabling of debuggee's virtual address space randomization."), _("\
9511 Show disabling of debuggee's virtual address space randomization."), _("\
9512 When this mode is on (which is the default), randomization of the virtual\n\
9513 address space is disabled. Standalone programs run with the randomization\n\
9514 enabled by default on some platforms."),
9515 &set_disable_randomization
,
9516 &show_disable_randomization
,
9517 &setlist
, &showlist
);
9519 /* ptid initializations */
9520 inferior_ptid
= null_ptid
;
9521 target_last_wait_ptid
= minus_one_ptid
;
9523 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9524 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9525 observer_attach_thread_exit (infrun_thread_thread_exit
);
9526 observer_attach_inferior_exit (infrun_inferior_exit
);
9528 /* Explicitly create without lookup, since that tries to create a
9529 value with a void typed value, and when we get here, gdbarch
9530 isn't initialized yet. At this point, we're quite sure there
9531 isn't another convenience variable of the same name. */
9532 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9534 add_setshow_boolean_cmd ("observer", no_class
,
9535 &observer_mode_1
, _("\
9536 Set whether gdb controls the inferior in observer mode."), _("\
9537 Show whether gdb controls the inferior in observer mode."), _("\
9538 In observer mode, GDB can get data from the inferior, but not\n\
9539 affect its execution. Registers and memory may not be changed,\n\
9540 breakpoints may not be set, and the program cannot be interrupted\n\