1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2016 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
1326 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1327 int nonsteppable_watchpoint_p
,
1330 step_over_info
.aspace
= aspace
;
1331 step_over_info
.address
= address
;
1332 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1333 step_over_info
.thread
= thread
;
1336 /* Called when we're not longer stepping over a breakpoint / an
1337 instruction, so all breakpoints are free to be (re)inserted. */
1340 clear_step_over_info (void)
1343 fprintf_unfiltered (gdb_stdlog
,
1344 "infrun: clear_step_over_info\n");
1345 step_over_info
.aspace
= NULL
;
1346 step_over_info
.address
= 0;
1347 step_over_info
.nonsteppable_watchpoint_p
= 0;
1348 step_over_info
.thread
= -1;
1354 stepping_past_instruction_at (struct address_space
*aspace
,
1357 return (step_over_info
.aspace
!= NULL
1358 && breakpoint_address_match (aspace
, address
,
1359 step_over_info
.aspace
,
1360 step_over_info
.address
));
1366 thread_is_stepping_over_breakpoint (int thread
)
1368 return (step_over_info
.thread
!= -1
1369 && thread
== step_over_info
.thread
);
1375 stepping_past_nonsteppable_watchpoint (void)
1377 return step_over_info
.nonsteppable_watchpoint_p
;
1380 /* Returns true if step-over info is valid. */
1383 step_over_info_valid_p (void)
1385 return (step_over_info
.aspace
!= NULL
1386 || stepping_past_nonsteppable_watchpoint ());
1390 /* Displaced stepping. */
1392 /* In non-stop debugging mode, we must take special care to manage
1393 breakpoints properly; in particular, the traditional strategy for
1394 stepping a thread past a breakpoint it has hit is unsuitable.
1395 'Displaced stepping' is a tactic for stepping one thread past a
1396 breakpoint it has hit while ensuring that other threads running
1397 concurrently will hit the breakpoint as they should.
1399 The traditional way to step a thread T off a breakpoint in a
1400 multi-threaded program in all-stop mode is as follows:
1402 a0) Initially, all threads are stopped, and breakpoints are not
1404 a1) We single-step T, leaving breakpoints uninserted.
1405 a2) We insert breakpoints, and resume all threads.
1407 In non-stop debugging, however, this strategy is unsuitable: we
1408 don't want to have to stop all threads in the system in order to
1409 continue or step T past a breakpoint. Instead, we use displaced
1412 n0) Initially, T is stopped, other threads are running, and
1413 breakpoints are inserted.
1414 n1) We copy the instruction "under" the breakpoint to a separate
1415 location, outside the main code stream, making any adjustments
1416 to the instruction, register, and memory state as directed by
1418 n2) We single-step T over the instruction at its new location.
1419 n3) We adjust the resulting register and memory state as directed
1420 by T's architecture. This includes resetting T's PC to point
1421 back into the main instruction stream.
1424 This approach depends on the following gdbarch methods:
1426 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1427 indicate where to copy the instruction, and how much space must
1428 be reserved there. We use these in step n1.
1430 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1431 address, and makes any necessary adjustments to the instruction,
1432 register contents, and memory. We use this in step n1.
1434 - gdbarch_displaced_step_fixup adjusts registers and memory after
1435 we have successfuly single-stepped the instruction, to yield the
1436 same effect the instruction would have had if we had executed it
1437 at its original address. We use this in step n3.
1439 - gdbarch_displaced_step_free_closure provides cleanup.
1441 The gdbarch_displaced_step_copy_insn and
1442 gdbarch_displaced_step_fixup functions must be written so that
1443 copying an instruction with gdbarch_displaced_step_copy_insn,
1444 single-stepping across the copied instruction, and then applying
1445 gdbarch_displaced_insn_fixup should have the same effects on the
1446 thread's memory and registers as stepping the instruction in place
1447 would have. Exactly which responsibilities fall to the copy and
1448 which fall to the fixup is up to the author of those functions.
1450 See the comments in gdbarch.sh for details.
1452 Note that displaced stepping and software single-step cannot
1453 currently be used in combination, although with some care I think
1454 they could be made to. Software single-step works by placing
1455 breakpoints on all possible subsequent instructions; if the
1456 displaced instruction is a PC-relative jump, those breakpoints
1457 could fall in very strange places --- on pages that aren't
1458 executable, or at addresses that are not proper instruction
1459 boundaries. (We do generally let other threads run while we wait
1460 to hit the software single-step breakpoint, and they might
1461 encounter such a corrupted instruction.) One way to work around
1462 this would be to have gdbarch_displaced_step_copy_insn fully
1463 simulate the effect of PC-relative instructions (and return NULL)
1464 on architectures that use software single-stepping.
1466 In non-stop mode, we can have independent and simultaneous step
1467 requests, so more than one thread may need to simultaneously step
1468 over a breakpoint. The current implementation assumes there is
1469 only one scratch space per process. In this case, we have to
1470 serialize access to the scratch space. If thread A wants to step
1471 over a breakpoint, but we are currently waiting for some other
1472 thread to complete a displaced step, we leave thread A stopped and
1473 place it in the displaced_step_request_queue. Whenever a displaced
1474 step finishes, we pick the next thread in the queue and start a new
1475 displaced step operation on it. See displaced_step_prepare and
1476 displaced_step_fixup for details. */
1478 /* Per-inferior displaced stepping state. */
1479 struct displaced_step_inferior_state
1481 /* Pointer to next in linked list. */
1482 struct displaced_step_inferior_state
*next
;
1484 /* The process this displaced step state refers to. */
1487 /* True if preparing a displaced step ever failed. If so, we won't
1488 try displaced stepping for this inferior again. */
1491 /* If this is not null_ptid, this is the thread carrying out a
1492 displaced single-step in process PID. This thread's state will
1493 require fixing up once it has completed its step. */
1496 /* The architecture the thread had when we stepped it. */
1497 struct gdbarch
*step_gdbarch
;
1499 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1500 for post-step cleanup. */
1501 struct displaced_step_closure
*step_closure
;
1503 /* The address of the original instruction, and the copy we
1505 CORE_ADDR step_original
, step_copy
;
1507 /* Saved contents of copy area. */
1508 gdb_byte
*step_saved_copy
;
1511 /* The list of states of processes involved in displaced stepping
1513 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1515 /* Get the displaced stepping state of process PID. */
1517 static struct displaced_step_inferior_state
*
1518 get_displaced_stepping_state (int pid
)
1520 struct displaced_step_inferior_state
*state
;
1522 for (state
= displaced_step_inferior_states
;
1524 state
= state
->next
)
1525 if (state
->pid
== pid
)
1531 /* Returns true if any inferior has a thread doing a displaced
1535 displaced_step_in_progress_any_inferior (void)
1537 struct displaced_step_inferior_state
*state
;
1539 for (state
= displaced_step_inferior_states
;
1541 state
= state
->next
)
1542 if (!ptid_equal (state
->step_ptid
, null_ptid
))
1548 /* Return true if thread represented by PTID is doing a displaced
1552 displaced_step_in_progress_thread (ptid_t ptid
)
1554 struct displaced_step_inferior_state
*displaced
;
1556 gdb_assert (!ptid_equal (ptid
, null_ptid
));
1558 displaced
= get_displaced_stepping_state (ptid_get_pid (ptid
));
1560 return (displaced
!= NULL
&& ptid_equal (displaced
->step_ptid
, ptid
));
1563 /* Return true if process PID has a thread doing a displaced step. */
1566 displaced_step_in_progress (int pid
)
1568 struct displaced_step_inferior_state
*displaced
;
1570 displaced
= get_displaced_stepping_state (pid
);
1571 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1577 /* Add a new displaced stepping state for process PID to the displaced
1578 stepping state list, or return a pointer to an already existing
1579 entry, if it already exists. Never returns NULL. */
1581 static struct displaced_step_inferior_state
*
1582 add_displaced_stepping_state (int pid
)
1584 struct displaced_step_inferior_state
*state
;
1586 for (state
= displaced_step_inferior_states
;
1588 state
= state
->next
)
1589 if (state
->pid
== pid
)
1592 state
= XCNEW (struct displaced_step_inferior_state
);
1594 state
->next
= displaced_step_inferior_states
;
1595 displaced_step_inferior_states
= state
;
1600 /* If inferior is in displaced stepping, and ADDR equals to starting address
1601 of copy area, return corresponding displaced_step_closure. Otherwise,
1604 struct displaced_step_closure
*
1605 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1607 struct displaced_step_inferior_state
*displaced
1608 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1610 /* If checking the mode of displaced instruction in copy area. */
1611 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1612 && (displaced
->step_copy
== addr
))
1613 return displaced
->step_closure
;
1618 /* Remove the displaced stepping state of process PID. */
1621 remove_displaced_stepping_state (int pid
)
1623 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1625 gdb_assert (pid
!= 0);
1627 it
= displaced_step_inferior_states
;
1628 prev_next_p
= &displaced_step_inferior_states
;
1633 *prev_next_p
= it
->next
;
1638 prev_next_p
= &it
->next
;
1644 infrun_inferior_exit (struct inferior
*inf
)
1646 remove_displaced_stepping_state (inf
->pid
);
1649 /* If ON, and the architecture supports it, GDB will use displaced
1650 stepping to step over breakpoints. If OFF, or if the architecture
1651 doesn't support it, GDB will instead use the traditional
1652 hold-and-step approach. If AUTO (which is the default), GDB will
1653 decide which technique to use to step over breakpoints depending on
1654 which of all-stop or non-stop mode is active --- displaced stepping
1655 in non-stop mode; hold-and-step in all-stop mode. */
1657 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1660 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1661 struct cmd_list_element
*c
,
1664 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1665 fprintf_filtered (file
,
1666 _("Debugger's willingness to use displaced stepping "
1667 "to step over breakpoints is %s (currently %s).\n"),
1668 value
, target_is_non_stop_p () ? "on" : "off");
1670 fprintf_filtered (file
,
1671 _("Debugger's willingness to use displaced stepping "
1672 "to step over breakpoints is %s.\n"), value
);
1675 /* Return non-zero if displaced stepping can/should be used to step
1676 over breakpoints of thread TP. */
1679 use_displaced_stepping (struct thread_info
*tp
)
1681 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
1682 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1683 struct displaced_step_inferior_state
*displaced_state
;
1685 displaced_state
= get_displaced_stepping_state (ptid_get_pid (tp
->ptid
));
1687 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1688 && target_is_non_stop_p ())
1689 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1690 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1691 && find_record_target () == NULL
1692 && (displaced_state
== NULL
1693 || !displaced_state
->failed_before
));
1696 /* Clean out any stray displaced stepping state. */
1698 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1700 /* Indicate that there is no cleanup pending. */
1701 displaced
->step_ptid
= null_ptid
;
1703 if (displaced
->step_closure
)
1705 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1706 displaced
->step_closure
);
1707 displaced
->step_closure
= NULL
;
1712 displaced_step_clear_cleanup (void *arg
)
1714 struct displaced_step_inferior_state
*state
1715 = (struct displaced_step_inferior_state
*) arg
;
1717 displaced_step_clear (state
);
1720 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1722 displaced_step_dump_bytes (struct ui_file
*file
,
1723 const gdb_byte
*buf
,
1728 for (i
= 0; i
< len
; i
++)
1729 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1730 fputs_unfiltered ("\n", file
);
1733 /* Prepare to single-step, using displaced stepping.
1735 Note that we cannot use displaced stepping when we have a signal to
1736 deliver. If we have a signal to deliver and an instruction to step
1737 over, then after the step, there will be no indication from the
1738 target whether the thread entered a signal handler or ignored the
1739 signal and stepped over the instruction successfully --- both cases
1740 result in a simple SIGTRAP. In the first case we mustn't do a
1741 fixup, and in the second case we must --- but we can't tell which.
1742 Comments in the code for 'random signals' in handle_inferior_event
1743 explain how we handle this case instead.
1745 Returns 1 if preparing was successful -- this thread is going to be
1746 stepped now; 0 if displaced stepping this thread got queued; or -1
1747 if this instruction can't be displaced stepped. */
1750 displaced_step_prepare_throw (ptid_t ptid
)
1752 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1753 struct thread_info
*tp
= find_thread_ptid (ptid
);
1754 struct regcache
*regcache
= get_thread_regcache (ptid
);
1755 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1756 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1757 CORE_ADDR original
, copy
;
1759 struct displaced_step_closure
*closure
;
1760 struct displaced_step_inferior_state
*displaced
;
1763 /* We should never reach this function if the architecture does not
1764 support displaced stepping. */
1765 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1767 /* Nor if the thread isn't meant to step over a breakpoint. */
1768 gdb_assert (tp
->control
.trap_expected
);
1770 /* Disable range stepping while executing in the scratch pad. We
1771 want a single-step even if executing the displaced instruction in
1772 the scratch buffer lands within the stepping range (e.g., a
1774 tp
->control
.may_range_step
= 0;
1776 /* We have to displaced step one thread at a time, as we only have
1777 access to a single scratch space per inferior. */
1779 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1781 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1783 /* Already waiting for a displaced step to finish. Defer this
1784 request and place in queue. */
1786 if (debug_displaced
)
1787 fprintf_unfiltered (gdb_stdlog
,
1788 "displaced: deferring step of %s\n",
1789 target_pid_to_str (ptid
));
1791 thread_step_over_chain_enqueue (tp
);
1796 if (debug_displaced
)
1797 fprintf_unfiltered (gdb_stdlog
,
1798 "displaced: stepping %s now\n",
1799 target_pid_to_str (ptid
));
1802 displaced_step_clear (displaced
);
1804 old_cleanups
= save_inferior_ptid ();
1805 inferior_ptid
= ptid
;
1807 original
= regcache_read_pc (regcache
);
1809 copy
= gdbarch_displaced_step_location (gdbarch
);
1810 len
= gdbarch_max_insn_length (gdbarch
);
1812 if (breakpoint_in_range_p (aspace
, copy
, len
))
1814 /* There's a breakpoint set in the scratch pad location range
1815 (which is usually around the entry point). We'd either
1816 install it before resuming, which would overwrite/corrupt the
1817 scratch pad, or if it was already inserted, this displaced
1818 step would overwrite it. The latter is OK in the sense that
1819 we already assume that no thread is going to execute the code
1820 in the scratch pad range (after initial startup) anyway, but
1821 the former is unacceptable. Simply punt and fallback to
1822 stepping over this breakpoint in-line. */
1823 if (debug_displaced
)
1825 fprintf_unfiltered (gdb_stdlog
,
1826 "displaced: breakpoint set in scratch pad. "
1827 "Stepping over breakpoint in-line instead.\n");
1830 do_cleanups (old_cleanups
);
1834 /* Save the original contents of the copy area. */
1835 displaced
->step_saved_copy
= (gdb_byte
*) xmalloc (len
);
1836 ignore_cleanups
= make_cleanup (free_current_contents
,
1837 &displaced
->step_saved_copy
);
1838 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1840 throw_error (MEMORY_ERROR
,
1841 _("Error accessing memory address %s (%s) for "
1842 "displaced-stepping scratch space."),
1843 paddress (gdbarch
, copy
), safe_strerror (status
));
1844 if (debug_displaced
)
1846 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1847 paddress (gdbarch
, copy
));
1848 displaced_step_dump_bytes (gdb_stdlog
,
1849 displaced
->step_saved_copy
,
1853 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1854 original
, copy
, regcache
);
1855 if (closure
== NULL
)
1857 /* The architecture doesn't know how or want to displaced step
1858 this instruction or instruction sequence. Fallback to
1859 stepping over the breakpoint in-line. */
1860 do_cleanups (old_cleanups
);
1864 /* Save the information we need to fix things up if the step
1866 displaced
->step_ptid
= ptid
;
1867 displaced
->step_gdbarch
= gdbarch
;
1868 displaced
->step_closure
= closure
;
1869 displaced
->step_original
= original
;
1870 displaced
->step_copy
= copy
;
1872 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1874 /* Resume execution at the copy. */
1875 regcache_write_pc (regcache
, copy
);
1877 discard_cleanups (ignore_cleanups
);
1879 do_cleanups (old_cleanups
);
1881 if (debug_displaced
)
1882 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1883 paddress (gdbarch
, copy
));
1888 /* Wrapper for displaced_step_prepare_throw that disabled further
1889 attempts at displaced stepping if we get a memory error. */
1892 displaced_step_prepare (ptid_t ptid
)
1898 prepared
= displaced_step_prepare_throw (ptid
);
1900 CATCH (ex
, RETURN_MASK_ERROR
)
1902 struct displaced_step_inferior_state
*displaced_state
;
1904 if (ex
.error
!= MEMORY_ERROR
1905 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1906 throw_exception (ex
);
1910 fprintf_unfiltered (gdb_stdlog
,
1911 "infrun: disabling displaced stepping: %s\n",
1915 /* Be verbose if "set displaced-stepping" is "on", silent if
1917 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1919 warning (_("disabling displaced stepping: %s"),
1923 /* Disable further displaced stepping attempts. */
1925 = get_displaced_stepping_state (ptid_get_pid (ptid
));
1926 displaced_state
->failed_before
= 1;
1934 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1935 const gdb_byte
*myaddr
, int len
)
1937 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1939 inferior_ptid
= ptid
;
1940 write_memory (memaddr
, myaddr
, len
);
1941 do_cleanups (ptid_cleanup
);
1944 /* Restore the contents of the copy area for thread PTID. */
1947 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1950 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1952 write_memory_ptid (ptid
, displaced
->step_copy
,
1953 displaced
->step_saved_copy
, len
);
1954 if (debug_displaced
)
1955 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1956 target_pid_to_str (ptid
),
1957 paddress (displaced
->step_gdbarch
,
1958 displaced
->step_copy
));
1961 /* If we displaced stepped an instruction successfully, adjust
1962 registers and memory to yield the same effect the instruction would
1963 have had if we had executed it at its original address, and return
1964 1. If the instruction didn't complete, relocate the PC and return
1965 -1. If the thread wasn't displaced stepping, return 0. */
1968 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1970 struct cleanup
*old_cleanups
;
1971 struct displaced_step_inferior_state
*displaced
1972 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1975 /* Was any thread of this process doing a displaced step? */
1976 if (displaced
== NULL
)
1979 /* Was this event for the pid we displaced? */
1980 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1981 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1984 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1986 displaced_step_restore (displaced
, displaced
->step_ptid
);
1988 /* Fixup may need to read memory/registers. Switch to the thread
1989 that we're fixing up. Also, target_stopped_by_watchpoint checks
1990 the current thread. */
1991 switch_to_thread (event_ptid
);
1993 /* Did the instruction complete successfully? */
1994 if (signal
== GDB_SIGNAL_TRAP
1995 && !(target_stopped_by_watchpoint ()
1996 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1997 || target_have_steppable_watchpoint
)))
1999 /* Fix up the resulting state. */
2000 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
2001 displaced
->step_closure
,
2002 displaced
->step_original
,
2003 displaced
->step_copy
,
2004 get_thread_regcache (displaced
->step_ptid
));
2009 /* Since the instruction didn't complete, all we can do is
2011 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
2012 CORE_ADDR pc
= regcache_read_pc (regcache
);
2014 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
2015 regcache_write_pc (regcache
, pc
);
2019 do_cleanups (old_cleanups
);
2021 displaced
->step_ptid
= null_ptid
;
2026 /* Data to be passed around while handling an event. This data is
2027 discarded between events. */
2028 struct execution_control_state
2031 /* The thread that got the event, if this was a thread event; NULL
2033 struct thread_info
*event_thread
;
2035 struct target_waitstatus ws
;
2036 int stop_func_filled_in
;
2037 CORE_ADDR stop_func_start
;
2038 CORE_ADDR stop_func_end
;
2039 const char *stop_func_name
;
2042 /* True if the event thread hit the single-step breakpoint of
2043 another thread. Thus the event doesn't cause a stop, the thread
2044 needs to be single-stepped past the single-step breakpoint before
2045 we can switch back to the original stepping thread. */
2046 int hit_singlestep_breakpoint
;
2049 /* Clear ECS and set it to point at TP. */
2052 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
2054 memset (ecs
, 0, sizeof (*ecs
));
2055 ecs
->event_thread
= tp
;
2056 ecs
->ptid
= tp
->ptid
;
2059 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
2060 static void prepare_to_wait (struct execution_control_state
*ecs
);
2061 static int keep_going_stepped_thread (struct thread_info
*tp
);
2062 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
2064 /* Are there any pending step-over requests? If so, run all we can
2065 now and return true. Otherwise, return false. */
2068 start_step_over (void)
2070 struct thread_info
*tp
, *next
;
2072 /* Don't start a new step-over if we already have an in-line
2073 step-over operation ongoing. */
2074 if (step_over_info_valid_p ())
2077 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
2079 struct execution_control_state ecss
;
2080 struct execution_control_state
*ecs
= &ecss
;
2081 step_over_what step_what
;
2082 int must_be_in_line
;
2084 next
= thread_step_over_chain_next (tp
);
2086 /* If this inferior already has a displaced step in process,
2087 don't start a new one. */
2088 if (displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2091 step_what
= thread_still_needs_step_over (tp
);
2092 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
2093 || ((step_what
& STEP_OVER_BREAKPOINT
)
2094 && !use_displaced_stepping (tp
)));
2096 /* We currently stop all threads of all processes to step-over
2097 in-line. If we need to start a new in-line step-over, let
2098 any pending displaced steps finish first. */
2099 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
2102 thread_step_over_chain_remove (tp
);
2104 if (step_over_queue_head
== NULL
)
2107 fprintf_unfiltered (gdb_stdlog
,
2108 "infrun: step-over queue now empty\n");
2111 if (tp
->control
.trap_expected
2115 internal_error (__FILE__
, __LINE__
,
2116 "[%s] has inconsistent state: "
2117 "trap_expected=%d, resumed=%d, executing=%d\n",
2118 target_pid_to_str (tp
->ptid
),
2119 tp
->control
.trap_expected
,
2125 fprintf_unfiltered (gdb_stdlog
,
2126 "infrun: resuming [%s] for step-over\n",
2127 target_pid_to_str (tp
->ptid
));
2129 /* keep_going_pass_signal skips the step-over if the breakpoint
2130 is no longer inserted. In all-stop, we want to keep looking
2131 for a thread that needs a step-over instead of resuming TP,
2132 because we wouldn't be able to resume anything else until the
2133 target stops again. In non-stop, the resume always resumes
2134 only TP, so it's OK to let the thread resume freely. */
2135 if (!target_is_non_stop_p () && !step_what
)
2138 switch_to_thread (tp
->ptid
);
2139 reset_ecs (ecs
, tp
);
2140 keep_going_pass_signal (ecs
);
2142 if (!ecs
->wait_some_more
)
2143 error (_("Command aborted."));
2145 gdb_assert (tp
->resumed
);
2147 /* If we started a new in-line step-over, we're done. */
2148 if (step_over_info_valid_p ())
2150 gdb_assert (tp
->control
.trap_expected
);
2154 if (!target_is_non_stop_p ())
2156 /* On all-stop, shouldn't have resumed unless we needed a
2158 gdb_assert (tp
->control
.trap_expected
2159 || tp
->step_after_step_resume_breakpoint
);
2161 /* With remote targets (at least), in all-stop, we can't
2162 issue any further remote commands until the program stops
2167 /* Either the thread no longer needed a step-over, or a new
2168 displaced stepping sequence started. Even in the latter
2169 case, continue looking. Maybe we can also start another
2170 displaced step on a thread of other process. */
2176 /* Update global variables holding ptids to hold NEW_PTID if they were
2177 holding OLD_PTID. */
2179 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2181 struct displaced_step_inferior_state
*displaced
;
2183 if (ptid_equal (inferior_ptid
, old_ptid
))
2184 inferior_ptid
= new_ptid
;
2186 for (displaced
= displaced_step_inferior_states
;
2188 displaced
= displaced
->next
)
2190 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
2191 displaced
->step_ptid
= new_ptid
;
2198 /* Things to clean up if we QUIT out of resume (). */
2200 resume_cleanups (void *ignore
)
2202 if (!ptid_equal (inferior_ptid
, null_ptid
))
2203 delete_single_step_breakpoints (inferior_thread ());
2208 static const char schedlock_off
[] = "off";
2209 static const char schedlock_on
[] = "on";
2210 static const char schedlock_step
[] = "step";
2211 static const char schedlock_replay
[] = "replay";
2212 static const char *const scheduler_enums
[] = {
2219 static const char *scheduler_mode
= schedlock_replay
;
2221 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2222 struct cmd_list_element
*c
, const char *value
)
2224 fprintf_filtered (file
,
2225 _("Mode for locking scheduler "
2226 "during execution is \"%s\".\n"),
2231 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
2233 if (!target_can_lock_scheduler
)
2235 scheduler_mode
= schedlock_off
;
2236 error (_("Target '%s' cannot support this command."), target_shortname
);
2240 /* True if execution commands resume all threads of all processes by
2241 default; otherwise, resume only threads of the current inferior
2243 int sched_multi
= 0;
2245 /* Try to setup for software single stepping over the specified location.
2246 Return 1 if target_resume() should use hardware single step.
2248 GDBARCH the current gdbarch.
2249 PC the location to step over. */
2252 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2256 if (execution_direction
== EXEC_FORWARD
2257 && gdbarch_software_single_step_p (gdbarch
))
2258 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2266 user_visible_resume_ptid (int step
)
2272 /* With non-stop mode on, threads are always handled
2274 resume_ptid
= inferior_ptid
;
2276 else if ((scheduler_mode
== schedlock_on
)
2277 || (scheduler_mode
== schedlock_step
&& step
))
2279 /* User-settable 'scheduler' mode requires solo thread
2281 resume_ptid
= inferior_ptid
;
2283 else if ((scheduler_mode
== schedlock_replay
)
2284 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2286 /* User-settable 'scheduler' mode requires solo thread resume in replay
2288 resume_ptid
= inferior_ptid
;
2290 else if (!sched_multi
&& target_supports_multi_process ())
2292 /* Resume all threads of the current process (and none of other
2294 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2298 /* Resume all threads of all processes. */
2299 resume_ptid
= RESUME_ALL
;
2305 /* Return a ptid representing the set of threads that we will resume,
2306 in the perspective of the target, assuming run control handling
2307 does not require leaving some threads stopped (e.g., stepping past
2308 breakpoint). USER_STEP indicates whether we're about to start the
2309 target for a stepping command. */
2312 internal_resume_ptid (int user_step
)
2314 /* In non-stop, we always control threads individually. Note that
2315 the target may always work in non-stop mode even with "set
2316 non-stop off", in which case user_visible_resume_ptid could
2317 return a wildcard ptid. */
2318 if (target_is_non_stop_p ())
2319 return inferior_ptid
;
2321 return user_visible_resume_ptid (user_step
);
2324 /* Wrapper for target_resume, that handles infrun-specific
2328 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2330 struct thread_info
*tp
= inferior_thread ();
2332 /* Install inferior's terminal modes. */
2333 target_terminal_inferior ();
2335 /* Avoid confusing the next resume, if the next stop/resume
2336 happens to apply to another thread. */
2337 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2339 /* Advise target which signals may be handled silently.
2341 If we have removed breakpoints because we are stepping over one
2342 in-line (in any thread), we need to receive all signals to avoid
2343 accidentally skipping a breakpoint during execution of a signal
2346 Likewise if we're displaced stepping, otherwise a trap for a
2347 breakpoint in a signal handler might be confused with the
2348 displaced step finishing. We don't make the displaced_step_fixup
2349 step distinguish the cases instead, because:
2351 - a backtrace while stopped in the signal handler would show the
2352 scratch pad as frame older than the signal handler, instead of
2353 the real mainline code.
2355 - when the thread is later resumed, the signal handler would
2356 return to the scratch pad area, which would no longer be
2358 if (step_over_info_valid_p ()
2359 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2360 target_pass_signals (0, NULL
);
2362 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2364 target_resume (resume_ptid
, step
, sig
);
2366 target_commit_resume ();
2369 /* Resume the inferior, but allow a QUIT. This is useful if the user
2370 wants to interrupt some lengthy single-stepping operation
2371 (for child processes, the SIGINT goes to the inferior, and so
2372 we get a SIGINT random_signal, but for remote debugging and perhaps
2373 other targets, that's not true).
2375 SIG is the signal to give the inferior (zero for none). */
2377 resume (enum gdb_signal sig
)
2379 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2380 struct regcache
*regcache
= get_current_regcache ();
2381 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2382 struct thread_info
*tp
= inferior_thread ();
2383 CORE_ADDR pc
= regcache_read_pc (regcache
);
2384 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2386 /* This represents the user's step vs continue request. When
2387 deciding whether "set scheduler-locking step" applies, it's the
2388 user's intention that counts. */
2389 const int user_step
= tp
->control
.stepping_command
;
2390 /* This represents what we'll actually request the target to do.
2391 This can decay from a step to a continue, if e.g., we need to
2392 implement single-stepping with breakpoints (software
2396 gdb_assert (!thread_is_in_step_over_chain (tp
));
2400 if (tp
->suspend
.waitstatus_pending_p
)
2406 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2407 fprintf_unfiltered (gdb_stdlog
,
2408 "infrun: resume: thread %s has pending wait status %s "
2409 "(currently_stepping=%d).\n",
2410 target_pid_to_str (tp
->ptid
), statstr
,
2411 currently_stepping (tp
));
2417 /* FIXME: What should we do if we are supposed to resume this
2418 thread with a signal? Maybe we should maintain a queue of
2419 pending signals to deliver. */
2420 if (sig
!= GDB_SIGNAL_0
)
2422 warning (_("Couldn't deliver signal %s to %s."),
2423 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2426 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2427 discard_cleanups (old_cleanups
);
2429 if (target_can_async_p ())
2434 tp
->stepped_breakpoint
= 0;
2436 /* Depends on stepped_breakpoint. */
2437 step
= currently_stepping (tp
);
2439 if (current_inferior ()->waiting_for_vfork_done
)
2441 /* Don't try to single-step a vfork parent that is waiting for
2442 the child to get out of the shared memory region (by exec'ing
2443 or exiting). This is particularly important on software
2444 single-step archs, as the child process would trip on the
2445 software single step breakpoint inserted for the parent
2446 process. Since the parent will not actually execute any
2447 instruction until the child is out of the shared region (such
2448 are vfork's semantics), it is safe to simply continue it.
2449 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2450 the parent, and tell it to `keep_going', which automatically
2451 re-sets it stepping. */
2453 fprintf_unfiltered (gdb_stdlog
,
2454 "infrun: resume : clear step\n");
2459 fprintf_unfiltered (gdb_stdlog
,
2460 "infrun: resume (step=%d, signal=%s), "
2461 "trap_expected=%d, current thread [%s] at %s\n",
2462 step
, gdb_signal_to_symbol_string (sig
),
2463 tp
->control
.trap_expected
,
2464 target_pid_to_str (inferior_ptid
),
2465 paddress (gdbarch
, pc
));
2467 /* Normally, by the time we reach `resume', the breakpoints are either
2468 removed or inserted, as appropriate. The exception is if we're sitting
2469 at a permanent breakpoint; we need to step over it, but permanent
2470 breakpoints can't be removed. So we have to test for it here. */
2471 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2473 if (sig
!= GDB_SIGNAL_0
)
2475 /* We have a signal to pass to the inferior. The resume
2476 may, or may not take us to the signal handler. If this
2477 is a step, we'll need to stop in the signal handler, if
2478 there's one, (if the target supports stepping into
2479 handlers), or in the next mainline instruction, if
2480 there's no handler. If this is a continue, we need to be
2481 sure to run the handler with all breakpoints inserted.
2482 In all cases, set a breakpoint at the current address
2483 (where the handler returns to), and once that breakpoint
2484 is hit, resume skipping the permanent breakpoint. If
2485 that breakpoint isn't hit, then we've stepped into the
2486 signal handler (or hit some other event). We'll delete
2487 the step-resume breakpoint then. */
2490 fprintf_unfiltered (gdb_stdlog
,
2491 "infrun: resume: skipping permanent breakpoint, "
2492 "deliver signal first\n");
2494 clear_step_over_info ();
2495 tp
->control
.trap_expected
= 0;
2497 if (tp
->control
.step_resume_breakpoint
== NULL
)
2499 /* Set a "high-priority" step-resume, as we don't want
2500 user breakpoints at PC to trigger (again) when this
2502 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2503 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2505 tp
->step_after_step_resume_breakpoint
= step
;
2508 insert_breakpoints ();
2512 /* There's no signal to pass, we can go ahead and skip the
2513 permanent breakpoint manually. */
2515 fprintf_unfiltered (gdb_stdlog
,
2516 "infrun: resume: skipping permanent breakpoint\n");
2517 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2518 /* Update pc to reflect the new address from which we will
2519 execute instructions. */
2520 pc
= regcache_read_pc (regcache
);
2524 /* We've already advanced the PC, so the stepping part
2525 is done. Now we need to arrange for a trap to be
2526 reported to handle_inferior_event. Set a breakpoint
2527 at the current PC, and run to it. Don't update
2528 prev_pc, because if we end in
2529 switch_back_to_stepped_thread, we want the "expected
2530 thread advanced also" branch to be taken. IOW, we
2531 don't want this thread to step further from PC
2533 gdb_assert (!step_over_info_valid_p ());
2534 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2535 insert_breakpoints ();
2537 resume_ptid
= internal_resume_ptid (user_step
);
2538 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2539 discard_cleanups (old_cleanups
);
2546 /* If we have a breakpoint to step over, make sure to do a single
2547 step only. Same if we have software watchpoints. */
2548 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2549 tp
->control
.may_range_step
= 0;
2551 /* If enabled, step over breakpoints by executing a copy of the
2552 instruction at a different address.
2554 We can't use displaced stepping when we have a signal to deliver;
2555 the comments for displaced_step_prepare explain why. The
2556 comments in the handle_inferior event for dealing with 'random
2557 signals' explain what we do instead.
2559 We can't use displaced stepping when we are waiting for vfork_done
2560 event, displaced stepping breaks the vfork child similarly as single
2561 step software breakpoint. */
2562 if (tp
->control
.trap_expected
2563 && use_displaced_stepping (tp
)
2564 && !step_over_info_valid_p ()
2565 && sig
== GDB_SIGNAL_0
2566 && !current_inferior ()->waiting_for_vfork_done
)
2568 int prepared
= displaced_step_prepare (inferior_ptid
);
2573 fprintf_unfiltered (gdb_stdlog
,
2574 "Got placed in step-over queue\n");
2576 tp
->control
.trap_expected
= 0;
2577 discard_cleanups (old_cleanups
);
2580 else if (prepared
< 0)
2582 /* Fallback to stepping over the breakpoint in-line. */
2584 if (target_is_non_stop_p ())
2585 stop_all_threads ();
2587 set_step_over_info (get_regcache_aspace (regcache
),
2588 regcache_read_pc (regcache
), 0, tp
->global_num
);
2590 step
= maybe_software_singlestep (gdbarch
, pc
);
2592 insert_breakpoints ();
2594 else if (prepared
> 0)
2596 struct displaced_step_inferior_state
*displaced
;
2598 /* Update pc to reflect the new address from which we will
2599 execute instructions due to displaced stepping. */
2600 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2602 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2603 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2604 displaced
->step_closure
);
2608 /* Do we need to do it the hard way, w/temp breakpoints? */
2610 step
= maybe_software_singlestep (gdbarch
, pc
);
2612 /* Currently, our software single-step implementation leads to different
2613 results than hardware single-stepping in one situation: when stepping
2614 into delivering a signal which has an associated signal handler,
2615 hardware single-step will stop at the first instruction of the handler,
2616 while software single-step will simply skip execution of the handler.
2618 For now, this difference in behavior is accepted since there is no
2619 easy way to actually implement single-stepping into a signal handler
2620 without kernel support.
2622 However, there is one scenario where this difference leads to follow-on
2623 problems: if we're stepping off a breakpoint by removing all breakpoints
2624 and then single-stepping. In this case, the software single-step
2625 behavior means that even if there is a *breakpoint* in the signal
2626 handler, GDB still would not stop.
2628 Fortunately, we can at least fix this particular issue. We detect
2629 here the case where we are about to deliver a signal while software
2630 single-stepping with breakpoints removed. In this situation, we
2631 revert the decisions to remove all breakpoints and insert single-
2632 step breakpoints, and instead we install a step-resume breakpoint
2633 at the current address, deliver the signal without stepping, and
2634 once we arrive back at the step-resume breakpoint, actually step
2635 over the breakpoint we originally wanted to step over. */
2636 if (thread_has_single_step_breakpoints_set (tp
)
2637 && sig
!= GDB_SIGNAL_0
2638 && step_over_info_valid_p ())
2640 /* If we have nested signals or a pending signal is delivered
2641 immediately after a handler returns, might might already have
2642 a step-resume breakpoint set on the earlier handler. We cannot
2643 set another step-resume breakpoint; just continue on until the
2644 original breakpoint is hit. */
2645 if (tp
->control
.step_resume_breakpoint
== NULL
)
2647 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2648 tp
->step_after_step_resume_breakpoint
= 1;
2651 delete_single_step_breakpoints (tp
);
2653 clear_step_over_info ();
2654 tp
->control
.trap_expected
= 0;
2656 insert_breakpoints ();
2659 /* If STEP is set, it's a request to use hardware stepping
2660 facilities. But in that case, we should never
2661 use singlestep breakpoint. */
2662 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2664 /* Decide the set of threads to ask the target to resume. */
2665 if (tp
->control
.trap_expected
)
2667 /* We're allowing a thread to run past a breakpoint it has
2668 hit, either by single-stepping the thread with the breakpoint
2669 removed, or by displaced stepping, with the breakpoint inserted.
2670 In the former case, we need to single-step only this thread,
2671 and keep others stopped, as they can miss this breakpoint if
2672 allowed to run. That's not really a problem for displaced
2673 stepping, but, we still keep other threads stopped, in case
2674 another thread is also stopped for a breakpoint waiting for
2675 its turn in the displaced stepping queue. */
2676 resume_ptid
= inferior_ptid
;
2679 resume_ptid
= internal_resume_ptid (user_step
);
2681 if (execution_direction
!= EXEC_REVERSE
2682 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2684 /* There are two cases where we currently need to step a
2685 breakpoint instruction when we have a signal to deliver:
2687 - See handle_signal_stop where we handle random signals that
2688 could take out us out of the stepping range. Normally, in
2689 that case we end up continuing (instead of stepping) over the
2690 signal handler with a breakpoint at PC, but there are cases
2691 where we should _always_ single-step, even if we have a
2692 step-resume breakpoint, like when a software watchpoint is
2693 set. Assuming single-stepping and delivering a signal at the
2694 same time would takes us to the signal handler, then we could
2695 have removed the breakpoint at PC to step over it. However,
2696 some hardware step targets (like e.g., Mac OS) can't step
2697 into signal handlers, and for those, we need to leave the
2698 breakpoint at PC inserted, as otherwise if the handler
2699 recurses and executes PC again, it'll miss the breakpoint.
2700 So we leave the breakpoint inserted anyway, but we need to
2701 record that we tried to step a breakpoint instruction, so
2702 that adjust_pc_after_break doesn't end up confused.
2704 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2705 in one thread after another thread that was stepping had been
2706 momentarily paused for a step-over. When we re-resume the
2707 stepping thread, it may be resumed from that address with a
2708 breakpoint that hasn't trapped yet. Seen with
2709 gdb.threads/non-stop-fair-events.exp, on targets that don't
2710 do displaced stepping. */
2713 fprintf_unfiltered (gdb_stdlog
,
2714 "infrun: resume: [%s] stepped breakpoint\n",
2715 target_pid_to_str (tp
->ptid
));
2717 tp
->stepped_breakpoint
= 1;
2719 /* Most targets can step a breakpoint instruction, thus
2720 executing it normally. But if this one cannot, just
2721 continue and we will hit it anyway. */
2722 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2727 && tp
->control
.trap_expected
2728 && use_displaced_stepping (tp
)
2729 && !step_over_info_valid_p ())
2731 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2732 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2733 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2736 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2737 paddress (resume_gdbarch
, actual_pc
));
2738 read_memory (actual_pc
, buf
, sizeof (buf
));
2739 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2742 if (tp
->control
.may_range_step
)
2744 /* If we're resuming a thread with the PC out of the step
2745 range, then we're doing some nested/finer run control
2746 operation, like stepping the thread out of the dynamic
2747 linker or the displaced stepping scratch pad. We
2748 shouldn't have allowed a range step then. */
2749 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2752 do_target_resume (resume_ptid
, step
, sig
);
2754 discard_cleanups (old_cleanups
);
2761 /* Counter that tracks number of user visible stops. This can be used
2762 to tell whether a command has proceeded the inferior past the
2763 current location. This allows e.g., inferior function calls in
2764 breakpoint commands to not interrupt the command list. When the
2765 call finishes successfully, the inferior is standing at the same
2766 breakpoint as if nothing happened (and so we don't call
2768 static ULONGEST current_stop_id
;
2775 return current_stop_id
;
2778 /* Called when we report a user visible stop. */
2786 /* Clear out all variables saying what to do when inferior is continued.
2787 First do this, then set the ones you want, then call `proceed'. */
2790 clear_proceed_status_thread (struct thread_info
*tp
)
2793 fprintf_unfiltered (gdb_stdlog
,
2794 "infrun: clear_proceed_status_thread (%s)\n",
2795 target_pid_to_str (tp
->ptid
));
2797 /* If we're starting a new sequence, then the previous finished
2798 single-step is no longer relevant. */
2799 if (tp
->suspend
.waitstatus_pending_p
)
2801 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2804 fprintf_unfiltered (gdb_stdlog
,
2805 "infrun: clear_proceed_status: pending "
2806 "event of %s was a finished step. "
2808 target_pid_to_str (tp
->ptid
));
2810 tp
->suspend
.waitstatus_pending_p
= 0;
2811 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2813 else if (debug_infrun
)
2817 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2818 fprintf_unfiltered (gdb_stdlog
,
2819 "infrun: clear_proceed_status_thread: thread %s "
2820 "has pending wait status %s "
2821 "(currently_stepping=%d).\n",
2822 target_pid_to_str (tp
->ptid
), statstr
,
2823 currently_stepping (tp
));
2828 /* If this signal should not be seen by program, give it zero.
2829 Used for debugging signals. */
2830 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2831 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2833 thread_fsm_delete (tp
->thread_fsm
);
2834 tp
->thread_fsm
= NULL
;
2836 tp
->control
.trap_expected
= 0;
2837 tp
->control
.step_range_start
= 0;
2838 tp
->control
.step_range_end
= 0;
2839 tp
->control
.may_range_step
= 0;
2840 tp
->control
.step_frame_id
= null_frame_id
;
2841 tp
->control
.step_stack_frame_id
= null_frame_id
;
2842 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2843 tp
->control
.step_start_function
= NULL
;
2844 tp
->stop_requested
= 0;
2846 tp
->control
.stop_step
= 0;
2848 tp
->control
.proceed_to_finish
= 0;
2850 tp
->control
.stepping_command
= 0;
2852 /* Discard any remaining commands or status from previous stop. */
2853 bpstat_clear (&tp
->control
.stop_bpstat
);
2857 clear_proceed_status (int step
)
2859 /* With scheduler-locking replay, stop replaying other threads if we're
2860 not replaying the user-visible resume ptid.
2862 This is a convenience feature to not require the user to explicitly
2863 stop replaying the other threads. We're assuming that the user's
2864 intent is to resume tracing the recorded process. */
2865 if (!non_stop
&& scheduler_mode
== schedlock_replay
2866 && target_record_is_replaying (minus_one_ptid
)
2867 && !target_record_will_replay (user_visible_resume_ptid (step
),
2868 execution_direction
))
2869 target_record_stop_replaying ();
2873 struct thread_info
*tp
;
2876 resume_ptid
= user_visible_resume_ptid (step
);
2878 /* In all-stop mode, delete the per-thread status of all threads
2879 we're about to resume, implicitly and explicitly. */
2880 ALL_NON_EXITED_THREADS (tp
)
2882 if (!ptid_match (tp
->ptid
, resume_ptid
))
2884 clear_proceed_status_thread (tp
);
2888 if (!ptid_equal (inferior_ptid
, null_ptid
))
2890 struct inferior
*inferior
;
2894 /* If in non-stop mode, only delete the per-thread status of
2895 the current thread. */
2896 clear_proceed_status_thread (inferior_thread ());
2899 inferior
= current_inferior ();
2900 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2903 observer_notify_about_to_proceed ();
2906 /* Returns true if TP is still stopped at a breakpoint that needs
2907 stepping-over in order to make progress. If the breakpoint is gone
2908 meanwhile, we can skip the whole step-over dance. */
2911 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2913 if (tp
->stepping_over_breakpoint
)
2915 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2917 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2918 regcache_read_pc (regcache
))
2919 == ordinary_breakpoint_here
)
2922 tp
->stepping_over_breakpoint
= 0;
2928 /* Check whether thread TP still needs to start a step-over in order
2929 to make progress when resumed. Returns an bitwise or of enum
2930 step_over_what bits, indicating what needs to be stepped over. */
2932 static step_over_what
2933 thread_still_needs_step_over (struct thread_info
*tp
)
2935 step_over_what what
= 0;
2937 if (thread_still_needs_step_over_bp (tp
))
2938 what
|= STEP_OVER_BREAKPOINT
;
2940 if (tp
->stepping_over_watchpoint
2941 && !target_have_steppable_watchpoint
)
2942 what
|= STEP_OVER_WATCHPOINT
;
2947 /* Returns true if scheduler locking applies. STEP indicates whether
2948 we're about to do a step/next-like command to a thread. */
2951 schedlock_applies (struct thread_info
*tp
)
2953 return (scheduler_mode
== schedlock_on
2954 || (scheduler_mode
== schedlock_step
2955 && tp
->control
.stepping_command
)
2956 || (scheduler_mode
== schedlock_replay
2957 && target_record_will_replay (minus_one_ptid
,
2958 execution_direction
)));
2961 /* Basic routine for continuing the program in various fashions.
2963 ADDR is the address to resume at, or -1 for resume where stopped.
2964 SIGGNAL is the signal to give it, or 0 for none,
2965 or -1 for act according to how it stopped.
2966 STEP is nonzero if should trap after one instruction.
2967 -1 means return after that and print nothing.
2968 You should probably set various step_... variables
2969 before calling here, if you are stepping.
2971 You should call clear_proceed_status before calling proceed. */
2974 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2976 struct regcache
*regcache
;
2977 struct gdbarch
*gdbarch
;
2978 struct thread_info
*tp
;
2980 struct address_space
*aspace
;
2982 struct execution_control_state ecss
;
2983 struct execution_control_state
*ecs
= &ecss
;
2984 struct cleanup
*old_chain
;
2985 struct cleanup
*defer_resume_cleanup
;
2988 /* If we're stopped at a fork/vfork, follow the branch set by the
2989 "set follow-fork-mode" command; otherwise, we'll just proceed
2990 resuming the current thread. */
2991 if (!follow_fork ())
2993 /* The target for some reason decided not to resume. */
2995 if (target_can_async_p ())
2996 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3000 /* We'll update this if & when we switch to a new thread. */
3001 previous_inferior_ptid
= inferior_ptid
;
3003 regcache
= get_current_regcache ();
3004 gdbarch
= get_regcache_arch (regcache
);
3005 aspace
= get_regcache_aspace (regcache
);
3006 pc
= regcache_read_pc (regcache
);
3007 tp
= inferior_thread ();
3009 /* Fill in with reasonable starting values. */
3010 init_thread_stepping_state (tp
);
3012 gdb_assert (!thread_is_in_step_over_chain (tp
));
3014 if (addr
== (CORE_ADDR
) -1)
3017 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3018 && execution_direction
!= EXEC_REVERSE
)
3019 /* There is a breakpoint at the address we will resume at,
3020 step one instruction before inserting breakpoints so that
3021 we do not stop right away (and report a second hit at this
3024 Note, we don't do this in reverse, because we won't
3025 actually be executing the breakpoint insn anyway.
3026 We'll be (un-)executing the previous instruction. */
3027 tp
->stepping_over_breakpoint
= 1;
3028 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3029 && gdbarch_single_step_through_delay (gdbarch
,
3030 get_current_frame ()))
3031 /* We stepped onto an instruction that needs to be stepped
3032 again before re-inserting the breakpoint, do so. */
3033 tp
->stepping_over_breakpoint
= 1;
3037 regcache_write_pc (regcache
, addr
);
3040 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3041 tp
->suspend
.stop_signal
= siggnal
;
3043 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3045 /* If an exception is thrown from this point on, make sure to
3046 propagate GDB's knowledge of the executing state to the
3047 frontend/user running state. */
3048 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3050 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3051 threads (e.g., we might need to set threads stepping over
3052 breakpoints first), from the user/frontend's point of view, all
3053 threads in RESUME_PTID are now running. Unless we're calling an
3054 inferior function, as in that case we pretend the inferior
3055 doesn't run at all. */
3056 if (!tp
->control
.in_infcall
)
3057 set_running (resume_ptid
, 1);
3060 fprintf_unfiltered (gdb_stdlog
,
3061 "infrun: proceed (addr=%s, signal=%s)\n",
3062 paddress (gdbarch
, addr
),
3063 gdb_signal_to_symbol_string (siggnal
));
3065 annotate_starting ();
3067 /* Make sure that output from GDB appears before output from the
3069 gdb_flush (gdb_stdout
);
3071 /* In a multi-threaded task we may select another thread and
3072 then continue or step.
3074 But if a thread that we're resuming had stopped at a breakpoint,
3075 it will immediately cause another breakpoint stop without any
3076 execution (i.e. it will report a breakpoint hit incorrectly). So
3077 we must step over it first.
3079 Look for threads other than the current (TP) that reported a
3080 breakpoint hit and haven't been resumed yet since. */
3082 /* If scheduler locking applies, we can avoid iterating over all
3084 if (!non_stop
&& !schedlock_applies (tp
))
3086 struct thread_info
*current
= tp
;
3088 ALL_NON_EXITED_THREADS (tp
)
3090 /* Ignore the current thread here. It's handled
3095 /* Ignore threads of processes we're not resuming. */
3096 if (!ptid_match (tp
->ptid
, resume_ptid
))
3099 if (!thread_still_needs_step_over (tp
))
3102 gdb_assert (!thread_is_in_step_over_chain (tp
));
3105 fprintf_unfiltered (gdb_stdlog
,
3106 "infrun: need to step-over [%s] first\n",
3107 target_pid_to_str (tp
->ptid
));
3109 thread_step_over_chain_enqueue (tp
);
3115 /* Enqueue the current thread last, so that we move all other
3116 threads over their breakpoints first. */
3117 if (tp
->stepping_over_breakpoint
)
3118 thread_step_over_chain_enqueue (tp
);
3120 /* If the thread isn't started, we'll still need to set its prev_pc,
3121 so that switch_back_to_stepped_thread knows the thread hasn't
3122 advanced. Must do this before resuming any thread, as in
3123 all-stop/remote, once we resume we can't send any other packet
3124 until the target stops again. */
3125 tp
->prev_pc
= regcache_read_pc (regcache
);
3127 defer_resume_cleanup
= make_cleanup_defer_target_commit_resume ();
3129 started
= start_step_over ();
3131 if (step_over_info_valid_p ())
3133 /* Either this thread started a new in-line step over, or some
3134 other thread was already doing one. In either case, don't
3135 resume anything else until the step-over is finished. */
3137 else if (started
&& !target_is_non_stop_p ())
3139 /* A new displaced stepping sequence was started. In all-stop,
3140 we can't talk to the target anymore until it next stops. */
3142 else if (!non_stop
&& target_is_non_stop_p ())
3144 /* In all-stop, but the target is always in non-stop mode.
3145 Start all other threads that are implicitly resumed too. */
3146 ALL_NON_EXITED_THREADS (tp
)
3148 /* Ignore threads of processes we're not resuming. */
3149 if (!ptid_match (tp
->ptid
, resume_ptid
))
3155 fprintf_unfiltered (gdb_stdlog
,
3156 "infrun: proceed: [%s] resumed\n",
3157 target_pid_to_str (tp
->ptid
));
3158 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3162 if (thread_is_in_step_over_chain (tp
))
3165 fprintf_unfiltered (gdb_stdlog
,
3166 "infrun: proceed: [%s] needs step-over\n",
3167 target_pid_to_str (tp
->ptid
));
3172 fprintf_unfiltered (gdb_stdlog
,
3173 "infrun: proceed: resuming %s\n",
3174 target_pid_to_str (tp
->ptid
));
3176 reset_ecs (ecs
, tp
);
3177 switch_to_thread (tp
->ptid
);
3178 keep_going_pass_signal (ecs
);
3179 if (!ecs
->wait_some_more
)
3180 error (_("Command aborted."));
3183 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3185 /* The thread wasn't started, and isn't queued, run it now. */
3186 reset_ecs (ecs
, tp
);
3187 switch_to_thread (tp
->ptid
);
3188 keep_going_pass_signal (ecs
);
3189 if (!ecs
->wait_some_more
)
3190 error (_("Command aborted."));
3193 do_cleanups (defer_resume_cleanup
);
3194 target_commit_resume ();
3196 discard_cleanups (old_chain
);
3198 /* Tell the event loop to wait for it to stop. If the target
3199 supports asynchronous execution, it'll do this from within
3201 if (!target_can_async_p ())
3202 mark_async_event_handler (infrun_async_inferior_event_token
);
3206 /* Start remote-debugging of a machine over a serial link. */
3209 start_remote (int from_tty
)
3211 struct inferior
*inferior
;
3213 inferior
= current_inferior ();
3214 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3216 /* Always go on waiting for the target, regardless of the mode. */
3217 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3218 indicate to wait_for_inferior that a target should timeout if
3219 nothing is returned (instead of just blocking). Because of this,
3220 targets expecting an immediate response need to, internally, set
3221 things up so that the target_wait() is forced to eventually
3223 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3224 differentiate to its caller what the state of the target is after
3225 the initial open has been performed. Here we're assuming that
3226 the target has stopped. It should be possible to eventually have
3227 target_open() return to the caller an indication that the target
3228 is currently running and GDB state should be set to the same as
3229 for an async run. */
3230 wait_for_inferior ();
3232 /* Now that the inferior has stopped, do any bookkeeping like
3233 loading shared libraries. We want to do this before normal_stop,
3234 so that the displayed frame is up to date. */
3235 post_create_inferior (¤t_target
, from_tty
);
3240 /* Initialize static vars when a new inferior begins. */
3243 init_wait_for_inferior (void)
3245 /* These are meaningless until the first time through wait_for_inferior. */
3247 breakpoint_init_inferior (inf_starting
);
3249 clear_proceed_status (0);
3251 target_last_wait_ptid
= minus_one_ptid
;
3253 previous_inferior_ptid
= inferior_ptid
;
3255 /* Discard any skipped inlined frames. */
3256 clear_inline_frame_state (minus_one_ptid
);
3261 static void handle_inferior_event (struct execution_control_state
*ecs
);
3263 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3264 struct execution_control_state
*ecs
);
3265 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3266 struct execution_control_state
*ecs
);
3267 static void handle_signal_stop (struct execution_control_state
*ecs
);
3268 static void check_exception_resume (struct execution_control_state
*,
3269 struct frame_info
*);
3271 static void end_stepping_range (struct execution_control_state
*ecs
);
3272 static void stop_waiting (struct execution_control_state
*ecs
);
3273 static void keep_going (struct execution_control_state
*ecs
);
3274 static void process_event_stop_test (struct execution_control_state
*ecs
);
3275 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3277 /* Callback for iterate over threads. If the thread is stopped, but
3278 the user/frontend doesn't know about that yet, go through
3279 normal_stop, as if the thread had just stopped now. ARG points at
3280 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
3281 ptid_is_pid(PTID) is true, applies to all threads of the process
3282 pointed at by PTID. Otherwise, apply only to the thread pointed by
3286 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
3288 ptid_t ptid
= * (ptid_t
*) arg
;
3290 if ((ptid_equal (info
->ptid
, ptid
)
3291 || ptid_equal (minus_one_ptid
, ptid
)
3292 || (ptid_is_pid (ptid
)
3293 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
3294 && is_running (info
->ptid
)
3295 && !is_executing (info
->ptid
))
3297 struct cleanup
*old_chain
;
3298 struct execution_control_state ecss
;
3299 struct execution_control_state
*ecs
= &ecss
;
3301 memset (ecs
, 0, sizeof (*ecs
));
3303 old_chain
= make_cleanup_restore_current_thread ();
3305 overlay_cache_invalid
= 1;
3306 /* Flush target cache before starting to handle each event.
3307 Target was running and cache could be stale. This is just a
3308 heuristic. Running threads may modify target memory, but we
3309 don't get any event. */
3310 target_dcache_invalidate ();
3312 /* Go through handle_inferior_event/normal_stop, so we always
3313 have consistent output as if the stop event had been
3315 ecs
->ptid
= info
->ptid
;
3316 ecs
->event_thread
= info
;
3317 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
3318 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
3320 handle_inferior_event (ecs
);
3322 if (!ecs
->wait_some_more
)
3324 /* Cancel any running execution command. */
3325 thread_cancel_execution_command (info
);
3330 do_cleanups (old_chain
);
3336 /* This function is attached as a "thread_stop_requested" observer.
3337 Cleanup local state that assumed the PTID was to be resumed, and
3338 report the stop to the frontend. */
3341 infrun_thread_stop_requested (ptid_t ptid
)
3343 struct thread_info
*tp
;
3345 /* PTID was requested to stop. Remove matching threads from the
3346 step-over queue, so we don't try to resume them
3348 ALL_NON_EXITED_THREADS (tp
)
3349 if (ptid_match (tp
->ptid
, ptid
))
3351 if (thread_is_in_step_over_chain (tp
))
3352 thread_step_over_chain_remove (tp
);
3355 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
3359 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3361 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3362 nullify_last_target_wait_ptid ();
3365 /* Delete the step resume, single-step and longjmp/exception resume
3366 breakpoints of TP. */
3369 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3371 delete_step_resume_breakpoint (tp
);
3372 delete_exception_resume_breakpoint (tp
);
3373 delete_single_step_breakpoints (tp
);
3376 /* If the target still has execution, call FUNC for each thread that
3377 just stopped. In all-stop, that's all the non-exited threads; in
3378 non-stop, that's the current thread, only. */
3380 typedef void (*for_each_just_stopped_thread_callback_func
)
3381 (struct thread_info
*tp
);
3384 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3386 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3389 if (target_is_non_stop_p ())
3391 /* If in non-stop mode, only the current thread stopped. */
3392 func (inferior_thread ());
3396 struct thread_info
*tp
;
3398 /* In all-stop mode, all threads have stopped. */
3399 ALL_NON_EXITED_THREADS (tp
)
3406 /* Delete the step resume and longjmp/exception resume breakpoints of
3407 the threads that just stopped. */
3410 delete_just_stopped_threads_infrun_breakpoints (void)
3412 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3415 /* Delete the single-step breakpoints of the threads that just
3419 delete_just_stopped_threads_single_step_breakpoints (void)
3421 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3424 /* A cleanup wrapper. */
3427 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3429 delete_just_stopped_threads_infrun_breakpoints ();
3435 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3436 const struct target_waitstatus
*ws
)
3438 char *status_string
= target_waitstatus_to_string (ws
);
3439 struct ui_file
*tmp_stream
= mem_fileopen ();
3442 /* The text is split over several lines because it was getting too long.
3443 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3444 output as a unit; we want only one timestamp printed if debug_timestamp
3447 fprintf_unfiltered (tmp_stream
,
3448 "infrun: target_wait (%d.%ld.%ld",
3449 ptid_get_pid (waiton_ptid
),
3450 ptid_get_lwp (waiton_ptid
),
3451 ptid_get_tid (waiton_ptid
));
3452 if (ptid_get_pid (waiton_ptid
) != -1)
3453 fprintf_unfiltered (tmp_stream
,
3454 " [%s]", target_pid_to_str (waiton_ptid
));
3455 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3456 fprintf_unfiltered (tmp_stream
,
3457 "infrun: %d.%ld.%ld [%s],\n",
3458 ptid_get_pid (result_ptid
),
3459 ptid_get_lwp (result_ptid
),
3460 ptid_get_tid (result_ptid
),
3461 target_pid_to_str (result_ptid
));
3462 fprintf_unfiltered (tmp_stream
,
3466 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3468 /* This uses %s in part to handle %'s in the text, but also to avoid
3469 a gcc error: the format attribute requires a string literal. */
3470 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3472 xfree (status_string
);
3474 ui_file_delete (tmp_stream
);
3477 /* Select a thread at random, out of those which are resumed and have
3480 static struct thread_info
*
3481 random_pending_event_thread (ptid_t waiton_ptid
)
3483 struct thread_info
*event_tp
;
3485 int random_selector
;
3487 /* First see how many events we have. Count only resumed threads
3488 that have an event pending. */
3489 ALL_NON_EXITED_THREADS (event_tp
)
3490 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3491 && event_tp
->resumed
3492 && event_tp
->suspend
.waitstatus_pending_p
)
3495 if (num_events
== 0)
3498 /* Now randomly pick a thread out of those that have had events. */
3499 random_selector
= (int)
3500 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3502 if (debug_infrun
&& num_events
> 1)
3503 fprintf_unfiltered (gdb_stdlog
,
3504 "infrun: Found %d events, selecting #%d\n",
3505 num_events
, random_selector
);
3507 /* Select the Nth thread that has had an event. */
3508 ALL_NON_EXITED_THREADS (event_tp
)
3509 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3510 && event_tp
->resumed
3511 && event_tp
->suspend
.waitstatus_pending_p
)
3512 if (random_selector
-- == 0)
3518 /* Wrapper for target_wait that first checks whether threads have
3519 pending statuses to report before actually asking the target for
3523 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3526 struct thread_info
*tp
;
3528 /* First check if there is a resumed thread with a wait status
3530 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3532 tp
= random_pending_event_thread (ptid
);
3537 fprintf_unfiltered (gdb_stdlog
,
3538 "infrun: Waiting for specific thread %s.\n",
3539 target_pid_to_str (ptid
));
3541 /* We have a specific thread to check. */
3542 tp
= find_thread_ptid (ptid
);
3543 gdb_assert (tp
!= NULL
);
3544 if (!tp
->suspend
.waitstatus_pending_p
)
3549 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3550 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3552 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3553 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3557 pc
= regcache_read_pc (regcache
);
3559 if (pc
!= tp
->suspend
.stop_pc
)
3562 fprintf_unfiltered (gdb_stdlog
,
3563 "infrun: PC of %s changed. was=%s, now=%s\n",
3564 target_pid_to_str (tp
->ptid
),
3565 paddress (gdbarch
, tp
->prev_pc
),
3566 paddress (gdbarch
, pc
));
3569 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3572 fprintf_unfiltered (gdb_stdlog
,
3573 "infrun: previous breakpoint of %s, at %s gone\n",
3574 target_pid_to_str (tp
->ptid
),
3575 paddress (gdbarch
, pc
));
3583 fprintf_unfiltered (gdb_stdlog
,
3584 "infrun: pending event of %s cancelled.\n",
3585 target_pid_to_str (tp
->ptid
));
3587 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3588 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3598 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3599 fprintf_unfiltered (gdb_stdlog
,
3600 "infrun: Using pending wait status %s for %s.\n",
3602 target_pid_to_str (tp
->ptid
));
3606 /* Now that we've selected our final event LWP, un-adjust its PC
3607 if it was a software breakpoint (and the target doesn't
3608 always adjust the PC itself). */
3609 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3610 && !target_supports_stopped_by_sw_breakpoint ())
3612 struct regcache
*regcache
;
3613 struct gdbarch
*gdbarch
;
3616 regcache
= get_thread_regcache (tp
->ptid
);
3617 gdbarch
= get_regcache_arch (regcache
);
3619 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3624 pc
= regcache_read_pc (regcache
);
3625 regcache_write_pc (regcache
, pc
+ decr_pc
);
3629 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3630 *status
= tp
->suspend
.waitstatus
;
3631 tp
->suspend
.waitstatus_pending_p
= 0;
3633 /* Wake up the event loop again, until all pending events are
3635 if (target_is_async_p ())
3636 mark_async_event_handler (infrun_async_inferior_event_token
);
3640 /* But if we don't find one, we'll have to wait. */
3642 if (deprecated_target_wait_hook
)
3643 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3645 event_ptid
= target_wait (ptid
, status
, options
);
3650 /* Prepare and stabilize the inferior for detaching it. E.g.,
3651 detaching while a thread is displaced stepping is a recipe for
3652 crashing it, as nothing would readjust the PC out of the scratch
3656 prepare_for_detach (void)
3658 struct inferior
*inf
= current_inferior ();
3659 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3660 struct cleanup
*old_chain_1
;
3661 struct displaced_step_inferior_state
*displaced
;
3663 displaced
= get_displaced_stepping_state (inf
->pid
);
3665 /* Is any thread of this process displaced stepping? If not,
3666 there's nothing else to do. */
3667 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3671 fprintf_unfiltered (gdb_stdlog
,
3672 "displaced-stepping in-process while detaching");
3674 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3677 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3679 struct cleanup
*old_chain_2
;
3680 struct execution_control_state ecss
;
3681 struct execution_control_state
*ecs
;
3684 memset (ecs
, 0, sizeof (*ecs
));
3686 overlay_cache_invalid
= 1;
3687 /* Flush target cache before starting to handle each event.
3688 Target was running and cache could be stale. This is just a
3689 heuristic. Running threads may modify target memory, but we
3690 don't get any event. */
3691 target_dcache_invalidate ();
3693 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3696 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3698 /* If an error happens while handling the event, propagate GDB's
3699 knowledge of the executing state to the frontend/user running
3701 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3704 /* Now figure out what to do with the result of the result. */
3705 handle_inferior_event (ecs
);
3707 /* No error, don't finish the state yet. */
3708 discard_cleanups (old_chain_2
);
3710 /* Breakpoints and watchpoints are not installed on the target
3711 at this point, and signals are passed directly to the
3712 inferior, so this must mean the process is gone. */
3713 if (!ecs
->wait_some_more
)
3715 discard_cleanups (old_chain_1
);
3716 error (_("Program exited while detaching"));
3720 discard_cleanups (old_chain_1
);
3723 /* Wait for control to return from inferior to debugger.
3725 If inferior gets a signal, we may decide to start it up again
3726 instead of returning. That is why there is a loop in this function.
3727 When this function actually returns it means the inferior
3728 should be left stopped and GDB should read more commands. */
3731 wait_for_inferior (void)
3733 struct cleanup
*old_cleanups
;
3734 struct cleanup
*thread_state_chain
;
3738 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3741 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3744 /* If an error happens while handling the event, propagate GDB's
3745 knowledge of the executing state to the frontend/user running
3747 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3751 struct execution_control_state ecss
;
3752 struct execution_control_state
*ecs
= &ecss
;
3753 ptid_t waiton_ptid
= minus_one_ptid
;
3755 memset (ecs
, 0, sizeof (*ecs
));
3757 overlay_cache_invalid
= 1;
3759 /* Flush target cache before starting to handle each event.
3760 Target was running and cache could be stale. This is just a
3761 heuristic. Running threads may modify target memory, but we
3762 don't get any event. */
3763 target_dcache_invalidate ();
3765 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3768 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3770 /* Now figure out what to do with the result of the result. */
3771 handle_inferior_event (ecs
);
3773 if (!ecs
->wait_some_more
)
3777 /* No error, don't finish the state yet. */
3778 discard_cleanups (thread_state_chain
);
3780 do_cleanups (old_cleanups
);
3783 /* Cleanup that reinstalls the readline callback handler, if the
3784 target is running in the background. If while handling the target
3785 event something triggered a secondary prompt, like e.g., a
3786 pagination prompt, we'll have removed the callback handler (see
3787 gdb_readline_wrapper_line). Need to do this as we go back to the
3788 event loop, ready to process further input. Note this has no
3789 effect if the handler hasn't actually been removed, because calling
3790 rl_callback_handler_install resets the line buffer, thus losing
3794 reinstall_readline_callback_handler_cleanup (void *arg
)
3796 struct ui
*ui
= current_ui
;
3800 /* We're not going back to the top level event loop yet. Don't
3801 install the readline callback, as it'd prep the terminal,
3802 readline-style (raw, noecho) (e.g., --batch). We'll install
3803 it the next time the prompt is displayed, when we're ready
3808 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3809 gdb_rl_callback_handler_reinstall ();
3812 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3813 that's just the event thread. In all-stop, that's all threads. */
3816 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3818 struct thread_info
*thr
= ecs
->event_thread
;
3820 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3821 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3825 ALL_NON_EXITED_THREADS (thr
)
3827 if (thr
->thread_fsm
== NULL
)
3829 if (thr
== ecs
->event_thread
)
3832 switch_to_thread (thr
->ptid
);
3833 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3836 if (ecs
->event_thread
!= NULL
)
3837 switch_to_thread (ecs
->event_thread
->ptid
);
3841 /* Helper for all_uis_check_sync_execution_done that works on the
3845 check_curr_ui_sync_execution_done (void)
3847 struct ui
*ui
= current_ui
;
3849 if (ui
->prompt_state
== PROMPT_NEEDED
3851 && !gdb_in_secondary_prompt_p (ui
))
3853 target_terminal_ours ();
3854 observer_notify_sync_execution_done ();
3855 ui_register_input_event_handler (ui
);
3862 all_uis_check_sync_execution_done (void)
3864 SWITCH_THRU_ALL_UIS ()
3866 check_curr_ui_sync_execution_done ();
3873 all_uis_on_sync_execution_starting (void)
3875 SWITCH_THRU_ALL_UIS ()
3877 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3878 async_disable_stdin ();
3882 /* Asynchronous version of wait_for_inferior. It is called by the
3883 event loop whenever a change of state is detected on the file
3884 descriptor corresponding to the target. It can be called more than
3885 once to complete a single execution command. In such cases we need
3886 to keep the state in a global variable ECSS. If it is the last time
3887 that this function is called for a single execution command, then
3888 report to the user that the inferior has stopped, and do the
3889 necessary cleanups. */
3892 fetch_inferior_event (void *client_data
)
3894 struct execution_control_state ecss
;
3895 struct execution_control_state
*ecs
= &ecss
;
3896 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3897 struct cleanup
*ts_old_chain
;
3899 ptid_t waiton_ptid
= minus_one_ptid
;
3901 memset (ecs
, 0, sizeof (*ecs
));
3903 /* Events are always processed with the main UI as current UI. This
3904 way, warnings, debug output, etc. are always consistently sent to
3905 the main console. */
3906 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3908 /* End up with readline processing input, if necessary. */
3909 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3911 /* We're handling a live event, so make sure we're doing live
3912 debugging. If we're looking at traceframes while the target is
3913 running, we're going to need to get back to that mode after
3914 handling the event. */
3917 make_cleanup_restore_current_traceframe ();
3918 set_current_traceframe (-1);
3922 /* In non-stop mode, the user/frontend should not notice a thread
3923 switch due to internal events. Make sure we reverse to the
3924 user selected thread and frame after handling the event and
3925 running any breakpoint commands. */
3926 make_cleanup_restore_current_thread ();
3928 overlay_cache_invalid
= 1;
3929 /* Flush target cache before starting to handle each event. Target
3930 was running and cache could be stale. This is just a heuristic.
3931 Running threads may modify target memory, but we don't get any
3933 target_dcache_invalidate ();
3935 scoped_restore save_exec_dir
3936 = make_scoped_restore (&execution_direction
, target_execution_direction ());
3938 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3939 target_can_async_p () ? TARGET_WNOHANG
: 0);
3942 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3944 /* If an error happens while handling the event, propagate GDB's
3945 knowledge of the executing state to the frontend/user running
3947 if (!target_is_non_stop_p ())
3948 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3950 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3952 /* Get executed before make_cleanup_restore_current_thread above to apply
3953 still for the thread which has thrown the exception. */
3954 make_bpstat_clear_actions_cleanup ();
3956 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3958 /* Now figure out what to do with the result of the result. */
3959 handle_inferior_event (ecs
);
3961 if (!ecs
->wait_some_more
)
3963 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3964 int should_stop
= 1;
3965 struct thread_info
*thr
= ecs
->event_thread
;
3966 int should_notify_stop
= 1;
3968 delete_just_stopped_threads_infrun_breakpoints ();
3972 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3974 if (thread_fsm
!= NULL
)
3975 should_stop
= thread_fsm_should_stop (thread_fsm
, thr
);
3984 clean_up_just_stopped_threads_fsms (ecs
);
3986 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3989 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
3992 if (should_notify_stop
)
3996 /* We may not find an inferior if this was a process exit. */
3997 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3998 proceeded
= normal_stop ();
4002 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
4009 /* No error, don't finish the thread states yet. */
4010 discard_cleanups (ts_old_chain
);
4012 /* Revert thread and frame. */
4013 do_cleanups (old_chain
);
4015 /* If a UI was in sync execution mode, and now isn't, restore its
4016 prompt (a synchronous execution command has finished, and we're
4017 ready for input). */
4018 all_uis_check_sync_execution_done ();
4021 && exec_done_display_p
4022 && (ptid_equal (inferior_ptid
, null_ptid
)
4023 || !is_running (inferior_ptid
)))
4024 printf_unfiltered (_("completed.\n"));
4027 /* Record the frame and location we're currently stepping through. */
4029 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
4031 struct thread_info
*tp
= inferior_thread ();
4033 tp
->control
.step_frame_id
= get_frame_id (frame
);
4034 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4036 tp
->current_symtab
= sal
.symtab
;
4037 tp
->current_line
= sal
.line
;
4040 /* Clear context switchable stepping state. */
4043 init_thread_stepping_state (struct thread_info
*tss
)
4045 tss
->stepped_breakpoint
= 0;
4046 tss
->stepping_over_breakpoint
= 0;
4047 tss
->stepping_over_watchpoint
= 0;
4048 tss
->step_after_step_resume_breakpoint
= 0;
4051 /* Set the cached copy of the last ptid/waitstatus. */
4054 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
4056 target_last_wait_ptid
= ptid
;
4057 target_last_waitstatus
= status
;
4060 /* Return the cached copy of the last pid/waitstatus returned by
4061 target_wait()/deprecated_target_wait_hook(). The data is actually
4062 cached by handle_inferior_event(), which gets called immediately
4063 after target_wait()/deprecated_target_wait_hook(). */
4066 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
4068 *ptidp
= target_last_wait_ptid
;
4069 *status
= target_last_waitstatus
;
4073 nullify_last_target_wait_ptid (void)
4075 target_last_wait_ptid
= minus_one_ptid
;
4078 /* Switch thread contexts. */
4081 context_switch (ptid_t ptid
)
4083 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4085 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4086 target_pid_to_str (inferior_ptid
));
4087 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4088 target_pid_to_str (ptid
));
4091 switch_to_thread (ptid
);
4094 /* If the target can't tell whether we've hit breakpoints
4095 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4096 check whether that could have been caused by a breakpoint. If so,
4097 adjust the PC, per gdbarch_decr_pc_after_break. */
4100 adjust_pc_after_break (struct thread_info
*thread
,
4101 struct target_waitstatus
*ws
)
4103 struct regcache
*regcache
;
4104 struct gdbarch
*gdbarch
;
4105 struct address_space
*aspace
;
4106 CORE_ADDR breakpoint_pc
, decr_pc
;
4108 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4109 we aren't, just return.
4111 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4112 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4113 implemented by software breakpoints should be handled through the normal
4116 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4117 different signals (SIGILL or SIGEMT for instance), but it is less
4118 clear where the PC is pointing afterwards. It may not match
4119 gdbarch_decr_pc_after_break. I don't know any specific target that
4120 generates these signals at breakpoints (the code has been in GDB since at
4121 least 1992) so I can not guess how to handle them here.
4123 In earlier versions of GDB, a target with
4124 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4125 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4126 target with both of these set in GDB history, and it seems unlikely to be
4127 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4129 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4132 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4135 /* In reverse execution, when a breakpoint is hit, the instruction
4136 under it has already been de-executed. The reported PC always
4137 points at the breakpoint address, so adjusting it further would
4138 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4141 B1 0x08000000 : INSN1
4142 B2 0x08000001 : INSN2
4144 PC -> 0x08000003 : INSN4
4146 Say you're stopped at 0x08000003 as above. Reverse continuing
4147 from that point should hit B2 as below. Reading the PC when the
4148 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4149 been de-executed already.
4151 B1 0x08000000 : INSN1
4152 B2 PC -> 0x08000001 : INSN2
4156 We can't apply the same logic as for forward execution, because
4157 we would wrongly adjust the PC to 0x08000000, since there's a
4158 breakpoint at PC - 1. We'd then report a hit on B1, although
4159 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4161 if (execution_direction
== EXEC_REVERSE
)
4164 /* If the target can tell whether the thread hit a SW breakpoint,
4165 trust it. Targets that can tell also adjust the PC
4167 if (target_supports_stopped_by_sw_breakpoint ())
4170 /* Note that relying on whether a breakpoint is planted in memory to
4171 determine this can fail. E.g,. the breakpoint could have been
4172 removed since. Or the thread could have been told to step an
4173 instruction the size of a breakpoint instruction, and only
4174 _after_ was a breakpoint inserted at its address. */
4176 /* If this target does not decrement the PC after breakpoints, then
4177 we have nothing to do. */
4178 regcache
= get_thread_regcache (thread
->ptid
);
4179 gdbarch
= get_regcache_arch (regcache
);
4181 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4185 aspace
= get_regcache_aspace (regcache
);
4187 /* Find the location where (if we've hit a breakpoint) the
4188 breakpoint would be. */
4189 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4191 /* If the target can't tell whether a software breakpoint triggered,
4192 fallback to figuring it out based on breakpoints we think were
4193 inserted in the target, and on whether the thread was stepped or
4196 /* Check whether there actually is a software breakpoint inserted at
4199 If in non-stop mode, a race condition is possible where we've
4200 removed a breakpoint, but stop events for that breakpoint were
4201 already queued and arrive later. To suppress those spurious
4202 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4203 and retire them after a number of stop events are reported. Note
4204 this is an heuristic and can thus get confused. The real fix is
4205 to get the "stopped by SW BP and needs adjustment" info out of
4206 the target/kernel (and thus never reach here; see above). */
4207 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4208 || (target_is_non_stop_p ()
4209 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4211 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4213 if (record_full_is_used ())
4214 record_full_gdb_operation_disable_set ();
4216 /* When using hardware single-step, a SIGTRAP is reported for both
4217 a completed single-step and a software breakpoint. Need to
4218 differentiate between the two, as the latter needs adjusting
4219 but the former does not.
4221 The SIGTRAP can be due to a completed hardware single-step only if
4222 - we didn't insert software single-step breakpoints
4223 - this thread is currently being stepped
4225 If any of these events did not occur, we must have stopped due
4226 to hitting a software breakpoint, and have to back up to the
4229 As a special case, we could have hardware single-stepped a
4230 software breakpoint. In this case (prev_pc == breakpoint_pc),
4231 we also need to back up to the breakpoint address. */
4233 if (thread_has_single_step_breakpoints_set (thread
)
4234 || !currently_stepping (thread
)
4235 || (thread
->stepped_breakpoint
4236 && thread
->prev_pc
== breakpoint_pc
))
4237 regcache_write_pc (regcache
, breakpoint_pc
);
4239 do_cleanups (old_cleanups
);
4244 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4246 for (frame
= get_prev_frame (frame
);
4248 frame
= get_prev_frame (frame
))
4250 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4252 if (get_frame_type (frame
) != INLINE_FRAME
)
4259 /* Auxiliary function that handles syscall entry/return events.
4260 It returns 1 if the inferior should keep going (and GDB
4261 should ignore the event), or 0 if the event deserves to be
4265 handle_syscall_event (struct execution_control_state
*ecs
)
4267 struct regcache
*regcache
;
4270 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4271 context_switch (ecs
->ptid
);
4273 regcache
= get_thread_regcache (ecs
->ptid
);
4274 syscall_number
= ecs
->ws
.value
.syscall_number
;
4275 stop_pc
= regcache_read_pc (regcache
);
4277 if (catch_syscall_enabled () > 0
4278 && catching_syscall_number (syscall_number
) > 0)
4281 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4284 ecs
->event_thread
->control
.stop_bpstat
4285 = bpstat_stop_status (get_regcache_aspace (regcache
),
4286 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4288 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4290 /* Catchpoint hit. */
4295 /* If no catchpoint triggered for this, then keep going. */
4300 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4303 fill_in_stop_func (struct gdbarch
*gdbarch
,
4304 struct execution_control_state
*ecs
)
4306 if (!ecs
->stop_func_filled_in
)
4308 /* Don't care about return value; stop_func_start and stop_func_name
4309 will both be 0 if it doesn't work. */
4310 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4311 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4312 ecs
->stop_func_start
4313 += gdbarch_deprecated_function_start_offset (gdbarch
);
4315 if (gdbarch_skip_entrypoint_p (gdbarch
))
4316 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4317 ecs
->stop_func_start
);
4319 ecs
->stop_func_filled_in
= 1;
4324 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4326 static enum stop_kind
4327 get_inferior_stop_soon (ptid_t ptid
)
4329 struct inferior
*inf
= find_inferior_ptid (ptid
);
4331 gdb_assert (inf
!= NULL
);
4332 return inf
->control
.stop_soon
;
4335 /* Wait for one event. Store the resulting waitstatus in WS, and
4336 return the event ptid. */
4339 wait_one (struct target_waitstatus
*ws
)
4342 ptid_t wait_ptid
= minus_one_ptid
;
4344 overlay_cache_invalid
= 1;
4346 /* Flush target cache before starting to handle each event.
4347 Target was running and cache could be stale. This is just a
4348 heuristic. Running threads may modify target memory, but we
4349 don't get any event. */
4350 target_dcache_invalidate ();
4352 if (deprecated_target_wait_hook
)
4353 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4355 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4358 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4363 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4364 instead of the current thread. */
4365 #define THREAD_STOPPED_BY(REASON) \
4367 thread_stopped_by_ ## REASON (ptid_t ptid) \
4369 struct cleanup *old_chain; \
4372 old_chain = save_inferior_ptid (); \
4373 inferior_ptid = ptid; \
4375 res = target_stopped_by_ ## REASON (); \
4377 do_cleanups (old_chain); \
4382 /* Generate thread_stopped_by_watchpoint. */
4383 THREAD_STOPPED_BY (watchpoint
)
4384 /* Generate thread_stopped_by_sw_breakpoint. */
4385 THREAD_STOPPED_BY (sw_breakpoint
)
4386 /* Generate thread_stopped_by_hw_breakpoint. */
4387 THREAD_STOPPED_BY (hw_breakpoint
)
4389 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4392 switch_to_thread_cleanup (void *ptid_p
)
4394 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4396 switch_to_thread (ptid
);
4399 /* Save the thread's event and stop reason to process it later. */
4402 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4404 struct regcache
*regcache
;
4405 struct address_space
*aspace
;
4411 statstr
= target_waitstatus_to_string (ws
);
4412 fprintf_unfiltered (gdb_stdlog
,
4413 "infrun: saving status %s for %d.%ld.%ld\n",
4415 ptid_get_pid (tp
->ptid
),
4416 ptid_get_lwp (tp
->ptid
),
4417 ptid_get_tid (tp
->ptid
));
4421 /* Record for later. */
4422 tp
->suspend
.waitstatus
= *ws
;
4423 tp
->suspend
.waitstatus_pending_p
= 1;
4425 regcache
= get_thread_regcache (tp
->ptid
);
4426 aspace
= get_regcache_aspace (regcache
);
4428 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4429 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4431 CORE_ADDR pc
= regcache_read_pc (regcache
);
4433 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4435 if (thread_stopped_by_watchpoint (tp
->ptid
))
4437 tp
->suspend
.stop_reason
4438 = TARGET_STOPPED_BY_WATCHPOINT
;
4440 else if (target_supports_stopped_by_sw_breakpoint ()
4441 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4443 tp
->suspend
.stop_reason
4444 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4446 else if (target_supports_stopped_by_hw_breakpoint ()
4447 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4449 tp
->suspend
.stop_reason
4450 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4452 else if (!target_supports_stopped_by_hw_breakpoint ()
4453 && hardware_breakpoint_inserted_here_p (aspace
,
4456 tp
->suspend
.stop_reason
4457 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4459 else if (!target_supports_stopped_by_sw_breakpoint ()
4460 && software_breakpoint_inserted_here_p (aspace
,
4463 tp
->suspend
.stop_reason
4464 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4466 else if (!thread_has_single_step_breakpoints_set (tp
)
4467 && currently_stepping (tp
))
4469 tp
->suspend
.stop_reason
4470 = TARGET_STOPPED_BY_SINGLE_STEP
;
4475 /* A cleanup that disables thread create/exit events. */
4478 disable_thread_events (void *arg
)
4480 target_thread_events (0);
4486 stop_all_threads (void)
4488 /* We may need multiple passes to discover all threads. */
4492 struct cleanup
*old_chain
;
4494 gdb_assert (target_is_non_stop_p ());
4497 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4499 entry_ptid
= inferior_ptid
;
4500 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4502 target_thread_events (1);
4503 make_cleanup (disable_thread_events
, NULL
);
4505 /* Request threads to stop, and then wait for the stops. Because
4506 threads we already know about can spawn more threads while we're
4507 trying to stop them, and we only learn about new threads when we
4508 update the thread list, do this in a loop, and keep iterating
4509 until two passes find no threads that need to be stopped. */
4510 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4513 fprintf_unfiltered (gdb_stdlog
,
4514 "infrun: stop_all_threads, pass=%d, "
4515 "iterations=%d\n", pass
, iterations
);
4519 struct target_waitstatus ws
;
4521 struct thread_info
*t
;
4523 update_thread_list ();
4525 /* Go through all threads looking for threads that we need
4526 to tell the target to stop. */
4527 ALL_NON_EXITED_THREADS (t
)
4531 /* If already stopping, don't request a stop again.
4532 We just haven't seen the notification yet. */
4533 if (!t
->stop_requested
)
4536 fprintf_unfiltered (gdb_stdlog
,
4537 "infrun: %s executing, "
4539 target_pid_to_str (t
->ptid
));
4540 target_stop (t
->ptid
);
4541 t
->stop_requested
= 1;
4546 fprintf_unfiltered (gdb_stdlog
,
4547 "infrun: %s executing, "
4548 "already stopping\n",
4549 target_pid_to_str (t
->ptid
));
4552 if (t
->stop_requested
)
4558 fprintf_unfiltered (gdb_stdlog
,
4559 "infrun: %s not executing\n",
4560 target_pid_to_str (t
->ptid
));
4562 /* The thread may be not executing, but still be
4563 resumed with a pending status to process. */
4571 /* If we find new threads on the second iteration, restart
4572 over. We want to see two iterations in a row with all
4577 event_ptid
= wait_one (&ws
);
4578 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4580 /* All resumed threads exited. */
4582 else if (ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4583 || ws
.kind
== TARGET_WAITKIND_EXITED
4584 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4588 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4590 fprintf_unfiltered (gdb_stdlog
,
4591 "infrun: %s exited while "
4592 "stopping threads\n",
4593 target_pid_to_str (ptid
));
4598 struct inferior
*inf
;
4600 t
= find_thread_ptid (event_ptid
);
4602 t
= add_thread (event_ptid
);
4604 t
->stop_requested
= 0;
4607 t
->control
.may_range_step
= 0;
4609 /* This may be the first time we see the inferior report
4611 inf
= find_inferior_ptid (event_ptid
);
4612 if (inf
->needs_setup
)
4614 switch_to_thread_no_regs (t
);
4618 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4619 && ws
.value
.sig
== GDB_SIGNAL_0
)
4621 /* We caught the event that we intended to catch, so
4622 there's no event pending. */
4623 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4624 t
->suspend
.waitstatus_pending_p
= 0;
4626 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4628 /* Add it back to the step-over queue. */
4631 fprintf_unfiltered (gdb_stdlog
,
4632 "infrun: displaced-step of %s "
4633 "canceled: adding back to the "
4634 "step-over queue\n",
4635 target_pid_to_str (t
->ptid
));
4637 t
->control
.trap_expected
= 0;
4638 thread_step_over_chain_enqueue (t
);
4643 enum gdb_signal sig
;
4644 struct regcache
*regcache
;
4650 statstr
= target_waitstatus_to_string (&ws
);
4651 fprintf_unfiltered (gdb_stdlog
,
4652 "infrun: target_wait %s, saving "
4653 "status for %d.%ld.%ld\n",
4655 ptid_get_pid (t
->ptid
),
4656 ptid_get_lwp (t
->ptid
),
4657 ptid_get_tid (t
->ptid
));
4661 /* Record for later. */
4662 save_waitstatus (t
, &ws
);
4664 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4665 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4667 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4669 /* Add it back to the step-over queue. */
4670 t
->control
.trap_expected
= 0;
4671 thread_step_over_chain_enqueue (t
);
4674 regcache
= get_thread_regcache (t
->ptid
);
4675 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4679 fprintf_unfiltered (gdb_stdlog
,
4680 "infrun: saved stop_pc=%s for %s "
4681 "(currently_stepping=%d)\n",
4682 paddress (target_gdbarch (),
4683 t
->suspend
.stop_pc
),
4684 target_pid_to_str (t
->ptid
),
4685 currently_stepping (t
));
4692 do_cleanups (old_chain
);
4695 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4698 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4701 handle_no_resumed (struct execution_control_state
*ecs
)
4703 struct inferior
*inf
;
4704 struct thread_info
*thread
;
4706 if (target_can_async_p ())
4713 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4721 /* There were no unwaited-for children left in the target, but,
4722 we're not synchronously waiting for events either. Just
4726 fprintf_unfiltered (gdb_stdlog
,
4727 "infrun: TARGET_WAITKIND_NO_RESUMED "
4728 "(ignoring: bg)\n");
4729 prepare_to_wait (ecs
);
4734 /* Otherwise, if we were running a synchronous execution command, we
4735 may need to cancel it and give the user back the terminal.
4737 In non-stop mode, the target can't tell whether we've already
4738 consumed previous stop events, so it can end up sending us a
4739 no-resumed event like so:
4741 #0 - thread 1 is left stopped
4743 #1 - thread 2 is resumed and hits breakpoint
4744 -> TARGET_WAITKIND_STOPPED
4746 #2 - thread 3 is resumed and exits
4747 this is the last resumed thread, so
4748 -> TARGET_WAITKIND_NO_RESUMED
4750 #3 - gdb processes stop for thread 2 and decides to re-resume
4753 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4754 thread 2 is now resumed, so the event should be ignored.
4756 IOW, if the stop for thread 2 doesn't end a foreground command,
4757 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4758 event. But it could be that the event meant that thread 2 itself
4759 (or whatever other thread was the last resumed thread) exited.
4761 To address this we refresh the thread list and check whether we
4762 have resumed threads _now_. In the example above, this removes
4763 thread 3 from the thread list. If thread 2 was re-resumed, we
4764 ignore this event. If we find no thread resumed, then we cancel
4765 the synchronous command show "no unwaited-for " to the user. */
4766 update_thread_list ();
4768 ALL_NON_EXITED_THREADS (thread
)
4770 if (thread
->executing
4771 || thread
->suspend
.waitstatus_pending_p
)
4773 /* There were no unwaited-for children left in the target at
4774 some point, but there are now. Just ignore. */
4776 fprintf_unfiltered (gdb_stdlog
,
4777 "infrun: TARGET_WAITKIND_NO_RESUMED "
4778 "(ignoring: found resumed)\n");
4779 prepare_to_wait (ecs
);
4784 /* Note however that we may find no resumed thread because the whole
4785 process exited meanwhile (thus updating the thread list results
4786 in an empty thread list). In this case we know we'll be getting
4787 a process exit event shortly. */
4793 thread
= any_live_thread_of_process (inf
->pid
);
4797 fprintf_unfiltered (gdb_stdlog
,
4798 "infrun: TARGET_WAITKIND_NO_RESUMED "
4799 "(expect process exit)\n");
4800 prepare_to_wait (ecs
);
4805 /* Go ahead and report the event. */
4809 /* Given an execution control state that has been freshly filled in by
4810 an event from the inferior, figure out what it means and take
4813 The alternatives are:
4815 1) stop_waiting and return; to really stop and return to the
4818 2) keep_going and return; to wait for the next event (set
4819 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4823 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4825 enum stop_kind stop_soon
;
4827 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4829 /* We had an event in the inferior, but we are not interested in
4830 handling it at this level. The lower layers have already
4831 done what needs to be done, if anything.
4833 One of the possible circumstances for this is when the
4834 inferior produces output for the console. The inferior has
4835 not stopped, and we are ignoring the event. Another possible
4836 circumstance is any event which the lower level knows will be
4837 reported multiple times without an intervening resume. */
4839 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4840 prepare_to_wait (ecs
);
4844 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4847 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4848 prepare_to_wait (ecs
);
4852 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4853 && handle_no_resumed (ecs
))
4856 /* Cache the last pid/waitstatus. */
4857 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4859 /* Always clear state belonging to the previous time we stopped. */
4860 stop_stack_dummy
= STOP_NONE
;
4862 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4864 /* No unwaited-for children left. IOW, all resumed children
4867 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4869 stop_print_frame
= 0;
4874 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4875 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4877 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4878 /* If it's a new thread, add it to the thread database. */
4879 if (ecs
->event_thread
== NULL
)
4880 ecs
->event_thread
= add_thread (ecs
->ptid
);
4882 /* Disable range stepping. If the next step request could use a
4883 range, this will be end up re-enabled then. */
4884 ecs
->event_thread
->control
.may_range_step
= 0;
4887 /* Dependent on valid ECS->EVENT_THREAD. */
4888 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4890 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4891 reinit_frame_cache ();
4893 breakpoint_retire_moribund ();
4895 /* First, distinguish signals caused by the debugger from signals
4896 that have to do with the program's own actions. Note that
4897 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4898 on the operating system version. Here we detect when a SIGILL or
4899 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4900 something similar for SIGSEGV, since a SIGSEGV will be generated
4901 when we're trying to execute a breakpoint instruction on a
4902 non-executable stack. This happens for call dummy breakpoints
4903 for architectures like SPARC that place call dummies on the
4905 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4906 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4907 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4908 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4910 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4912 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4913 regcache_read_pc (regcache
)))
4916 fprintf_unfiltered (gdb_stdlog
,
4917 "infrun: Treating signal as SIGTRAP\n");
4918 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4922 /* Mark the non-executing threads accordingly. In all-stop, all
4923 threads of all processes are stopped when we get any event
4924 reported. In non-stop mode, only the event thread stops. */
4928 if (!target_is_non_stop_p ())
4929 mark_ptid
= minus_one_ptid
;
4930 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4931 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4933 /* If we're handling a process exit in non-stop mode, even
4934 though threads haven't been deleted yet, one would think
4935 that there is nothing to do, as threads of the dead process
4936 will be soon deleted, and threads of any other process were
4937 left running. However, on some targets, threads survive a
4938 process exit event. E.g., for the "checkpoint" command,
4939 when the current checkpoint/fork exits, linux-fork.c
4940 automatically switches to another fork from within
4941 target_mourn_inferior, by associating the same
4942 inferior/thread to another fork. We haven't mourned yet at
4943 this point, but we must mark any threads left in the
4944 process as not-executing so that finish_thread_state marks
4945 them stopped (in the user's perspective) if/when we present
4946 the stop to the user. */
4947 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4950 mark_ptid
= ecs
->ptid
;
4952 set_executing (mark_ptid
, 0);
4954 /* Likewise the resumed flag. */
4955 set_resumed (mark_ptid
, 0);
4958 switch (ecs
->ws
.kind
)
4960 case TARGET_WAITKIND_LOADED
:
4962 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4963 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4964 context_switch (ecs
->ptid
);
4965 /* Ignore gracefully during startup of the inferior, as it might
4966 be the shell which has just loaded some objects, otherwise
4967 add the symbols for the newly loaded objects. Also ignore at
4968 the beginning of an attach or remote session; we will query
4969 the full list of libraries once the connection is
4972 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4973 if (stop_soon
== NO_STOP_QUIETLY
)
4975 struct regcache
*regcache
;
4977 regcache
= get_thread_regcache (ecs
->ptid
);
4979 handle_solib_event ();
4981 ecs
->event_thread
->control
.stop_bpstat
4982 = bpstat_stop_status (get_regcache_aspace (regcache
),
4983 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4985 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4987 /* A catchpoint triggered. */
4988 process_event_stop_test (ecs
);
4992 /* If requested, stop when the dynamic linker notifies
4993 gdb of events. This allows the user to get control
4994 and place breakpoints in initializer routines for
4995 dynamically loaded objects (among other things). */
4996 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4997 if (stop_on_solib_events
)
4999 /* Make sure we print "Stopped due to solib-event" in
5001 stop_print_frame
= 1;
5008 /* If we are skipping through a shell, or through shared library
5009 loading that we aren't interested in, resume the program. If
5010 we're running the program normally, also resume. */
5011 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5013 /* Loading of shared libraries might have changed breakpoint
5014 addresses. Make sure new breakpoints are inserted. */
5015 if (stop_soon
== NO_STOP_QUIETLY
)
5016 insert_breakpoints ();
5017 resume (GDB_SIGNAL_0
);
5018 prepare_to_wait (ecs
);
5022 /* But stop if we're attaching or setting up a remote
5024 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5025 || stop_soon
== STOP_QUIETLY_REMOTE
)
5028 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5033 internal_error (__FILE__
, __LINE__
,
5034 _("unhandled stop_soon: %d"), (int) stop_soon
);
5036 case TARGET_WAITKIND_SPURIOUS
:
5038 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
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 (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5049 context_switch (ecs
->ptid
);
5050 if (!switch_back_to_stepped_thread (ecs
))
5054 case TARGET_WAITKIND_EXITED
:
5055 case TARGET_WAITKIND_SIGNALLED
:
5058 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5059 fprintf_unfiltered (gdb_stdlog
,
5060 "infrun: TARGET_WAITKIND_EXITED\n");
5062 fprintf_unfiltered (gdb_stdlog
,
5063 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5066 inferior_ptid
= ecs
->ptid
;
5067 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
5068 set_current_program_space (current_inferior ()->pspace
);
5069 handle_vfork_child_exec_or_exit (0);
5070 target_terminal_ours (); /* Must do this before mourn anyway. */
5072 /* Clearing any previous state of convenience variables. */
5073 clear_exit_convenience_vars ();
5075 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5077 /* Record the exit code in the convenience variable $_exitcode, so
5078 that the user can inspect this again later. */
5079 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5080 (LONGEST
) ecs
->ws
.value
.integer
);
5082 /* Also record this in the inferior itself. */
5083 current_inferior ()->has_exit_code
= 1;
5084 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5086 /* Support the --return-child-result option. */
5087 return_child_result_value
= ecs
->ws
.value
.integer
;
5089 observer_notify_exited (ecs
->ws
.value
.integer
);
5093 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5094 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5096 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5098 /* Set the value of the internal variable $_exitsignal,
5099 which holds the signal uncaught by the inferior. */
5100 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5101 gdbarch_gdb_signal_to_target (gdbarch
,
5102 ecs
->ws
.value
.sig
));
5106 /* We don't have access to the target's method used for
5107 converting between signal numbers (GDB's internal
5108 representation <-> target's representation).
5109 Therefore, we cannot do a good job at displaying this
5110 information to the user. It's better to just warn
5111 her about it (if infrun debugging is enabled), and
5114 fprintf_filtered (gdb_stdlog
, _("\
5115 Cannot fill $_exitsignal with the correct signal number.\n"));
5118 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
5121 gdb_flush (gdb_stdout
);
5122 target_mourn_inferior (inferior_ptid
);
5123 stop_print_frame
= 0;
5127 /* The following are the only cases in which we keep going;
5128 the above cases end in a continue or goto. */
5129 case TARGET_WAITKIND_FORKED
:
5130 case TARGET_WAITKIND_VFORKED
:
5133 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5134 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
5136 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
5139 /* Check whether the inferior is displaced stepping. */
5141 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5142 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5144 /* If checking displaced stepping is supported, and thread
5145 ecs->ptid is displaced stepping. */
5146 if (displaced_step_in_progress_thread (ecs
->ptid
))
5148 struct inferior
*parent_inf
5149 = find_inferior_ptid (ecs
->ptid
);
5150 struct regcache
*child_regcache
;
5151 CORE_ADDR parent_pc
;
5153 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5154 indicating that the displaced stepping of syscall instruction
5155 has been done. Perform cleanup for parent process here. Note
5156 that this operation also cleans up the child process for vfork,
5157 because their pages are shared. */
5158 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
5159 /* Start a new step-over in another thread if there's one
5163 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5165 struct displaced_step_inferior_state
*displaced
5166 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
5168 /* Restore scratch pad for child process. */
5169 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
5172 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5173 the child's PC is also within the scratchpad. Set the child's PC
5174 to the parent's PC value, which has already been fixed up.
5175 FIXME: we use the parent's aspace here, although we're touching
5176 the child, because the child hasn't been added to the inferior
5177 list yet at this point. */
5180 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
5182 parent_inf
->aspace
);
5183 /* Read PC value of parent process. */
5184 parent_pc
= regcache_read_pc (regcache
);
5186 if (debug_displaced
)
5187 fprintf_unfiltered (gdb_stdlog
,
5188 "displaced: write child pc from %s to %s\n",
5190 regcache_read_pc (child_regcache
)),
5191 paddress (gdbarch
, parent_pc
));
5193 regcache_write_pc (child_regcache
, parent_pc
);
5197 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5198 context_switch (ecs
->ptid
);
5200 /* Immediately detach breakpoints from the child before there's
5201 any chance of letting the user delete breakpoints from the
5202 breakpoint lists. If we don't do this early, it's easy to
5203 leave left over traps in the child, vis: "break foo; catch
5204 fork; c; <fork>; del; c; <child calls foo>". We only follow
5205 the fork on the last `continue', and by that time the
5206 breakpoint at "foo" is long gone from the breakpoint table.
5207 If we vforked, then we don't need to unpatch here, since both
5208 parent and child are sharing the same memory pages; we'll
5209 need to unpatch at follow/detach time instead to be certain
5210 that new breakpoints added between catchpoint hit time and
5211 vfork follow are detached. */
5212 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5214 /* This won't actually modify the breakpoint list, but will
5215 physically remove the breakpoints from the child. */
5216 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5219 delete_just_stopped_threads_single_step_breakpoints ();
5221 /* In case the event is caught by a catchpoint, remember that
5222 the event is to be followed at the next resume of the thread,
5223 and not immediately. */
5224 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5226 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5228 ecs
->event_thread
->control
.stop_bpstat
5229 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5230 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5232 /* If no catchpoint triggered for this, then keep going. Note
5233 that we're interested in knowing the bpstat actually causes a
5234 stop, not just if it may explain the signal. Software
5235 watchpoints, for example, always appear in the bpstat. */
5236 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5242 = (follow_fork_mode_string
== follow_fork_mode_child
);
5244 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5246 should_resume
= follow_fork ();
5249 child
= ecs
->ws
.value
.related_pid
;
5251 /* At this point, the parent is marked running, and the
5252 child is marked stopped. */
5254 /* If not resuming the parent, mark it stopped. */
5255 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5256 set_running (parent
, 0);
5258 /* If resuming the child, mark it running. */
5259 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5260 set_running (child
, 1);
5262 /* In non-stop mode, also resume the other branch. */
5263 if (!detach_fork
&& (non_stop
5264 || (sched_multi
&& target_is_non_stop_p ())))
5267 switch_to_thread (parent
);
5269 switch_to_thread (child
);
5271 ecs
->event_thread
= inferior_thread ();
5272 ecs
->ptid
= inferior_ptid
;
5277 switch_to_thread (child
);
5279 switch_to_thread (parent
);
5281 ecs
->event_thread
= inferior_thread ();
5282 ecs
->ptid
= inferior_ptid
;
5290 process_event_stop_test (ecs
);
5293 case TARGET_WAITKIND_VFORK_DONE
:
5294 /* Done with the shared memory region. Re-insert breakpoints in
5295 the parent, and keep going. */
5298 fprintf_unfiltered (gdb_stdlog
,
5299 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5301 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5302 context_switch (ecs
->ptid
);
5304 current_inferior ()->waiting_for_vfork_done
= 0;
5305 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5306 /* This also takes care of reinserting breakpoints in the
5307 previously locked inferior. */
5311 case TARGET_WAITKIND_EXECD
:
5313 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5315 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5316 context_switch (ecs
->ptid
);
5318 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5320 /* Do whatever is necessary to the parent branch of the vfork. */
5321 handle_vfork_child_exec_or_exit (1);
5323 /* This causes the eventpoints and symbol table to be reset.
5324 Must do this now, before trying to determine whether to
5326 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5328 /* In follow_exec we may have deleted the original thread and
5329 created a new one. Make sure that the event thread is the
5330 execd thread for that case (this is a nop otherwise). */
5331 ecs
->event_thread
= inferior_thread ();
5333 ecs
->event_thread
->control
.stop_bpstat
5334 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5335 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5337 /* Note that this may be referenced from inside
5338 bpstat_stop_status above, through inferior_has_execd. */
5339 xfree (ecs
->ws
.value
.execd_pathname
);
5340 ecs
->ws
.value
.execd_pathname
= NULL
;
5342 /* If no catchpoint triggered for this, then keep going. */
5343 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5345 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5349 process_event_stop_test (ecs
);
5352 /* Be careful not to try to gather much state about a thread
5353 that's in a syscall. It's frequently a losing proposition. */
5354 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5356 fprintf_unfiltered (gdb_stdlog
,
5357 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5358 /* Getting the current syscall number. */
5359 if (handle_syscall_event (ecs
) == 0)
5360 process_event_stop_test (ecs
);
5363 /* Before examining the threads further, step this thread to
5364 get it entirely out of the syscall. (We get notice of the
5365 event when the thread is just on the verge of exiting a
5366 syscall. Stepping one instruction seems to get it back
5368 case TARGET_WAITKIND_SYSCALL_RETURN
:
5370 fprintf_unfiltered (gdb_stdlog
,
5371 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5372 if (handle_syscall_event (ecs
) == 0)
5373 process_event_stop_test (ecs
);
5376 case TARGET_WAITKIND_STOPPED
:
5378 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5379 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5380 handle_signal_stop (ecs
);
5383 case TARGET_WAITKIND_NO_HISTORY
:
5385 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5386 /* Reverse execution: target ran out of history info. */
5388 /* Switch to the stopped thread. */
5389 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5390 context_switch (ecs
->ptid
);
5392 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5394 delete_just_stopped_threads_single_step_breakpoints ();
5395 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5396 observer_notify_no_history ();
5402 /* A wrapper around handle_inferior_event_1, which also makes sure
5403 that all temporary struct value objects that were created during
5404 the handling of the event get deleted at the end. */
5407 handle_inferior_event (struct execution_control_state
*ecs
)
5409 struct value
*mark
= value_mark ();
5411 handle_inferior_event_1 (ecs
);
5412 /* Purge all temporary values created during the event handling,
5413 as it could be a long time before we return to the command level
5414 where such values would otherwise be purged. */
5415 value_free_to_mark (mark
);
5418 /* Restart threads back to what they were trying to do back when we
5419 paused them for an in-line step-over. The EVENT_THREAD thread is
5423 restart_threads (struct thread_info
*event_thread
)
5425 struct thread_info
*tp
;
5427 /* In case the instruction just stepped spawned a new thread. */
5428 update_thread_list ();
5430 ALL_NON_EXITED_THREADS (tp
)
5432 if (tp
== event_thread
)
5435 fprintf_unfiltered (gdb_stdlog
,
5436 "infrun: restart threads: "
5437 "[%s] is event thread\n",
5438 target_pid_to_str (tp
->ptid
));
5442 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5445 fprintf_unfiltered (gdb_stdlog
,
5446 "infrun: restart threads: "
5447 "[%s] not meant to be running\n",
5448 target_pid_to_str (tp
->ptid
));
5455 fprintf_unfiltered (gdb_stdlog
,
5456 "infrun: restart threads: [%s] resumed\n",
5457 target_pid_to_str (tp
->ptid
));
5458 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5462 if (thread_is_in_step_over_chain (tp
))
5465 fprintf_unfiltered (gdb_stdlog
,
5466 "infrun: restart threads: "
5467 "[%s] needs step-over\n",
5468 target_pid_to_str (tp
->ptid
));
5469 gdb_assert (!tp
->resumed
);
5474 if (tp
->suspend
.waitstatus_pending_p
)
5477 fprintf_unfiltered (gdb_stdlog
,
5478 "infrun: restart threads: "
5479 "[%s] has pending status\n",
5480 target_pid_to_str (tp
->ptid
));
5485 /* If some thread needs to start a step-over at this point, it
5486 should still be in the step-over queue, and thus skipped
5488 if (thread_still_needs_step_over (tp
))
5490 internal_error (__FILE__
, __LINE__
,
5491 "thread [%s] needs a step-over, but not in "
5492 "step-over queue\n",
5493 target_pid_to_str (tp
->ptid
));
5496 if (currently_stepping (tp
))
5499 fprintf_unfiltered (gdb_stdlog
,
5500 "infrun: restart threads: [%s] was stepping\n",
5501 target_pid_to_str (tp
->ptid
));
5502 keep_going_stepped_thread (tp
);
5506 struct execution_control_state ecss
;
5507 struct execution_control_state
*ecs
= &ecss
;
5510 fprintf_unfiltered (gdb_stdlog
,
5511 "infrun: restart threads: [%s] continuing\n",
5512 target_pid_to_str (tp
->ptid
));
5513 reset_ecs (ecs
, tp
);
5514 switch_to_thread (tp
->ptid
);
5515 keep_going_pass_signal (ecs
);
5520 /* Callback for iterate_over_threads. Find a resumed thread that has
5521 a pending waitstatus. */
5524 resumed_thread_with_pending_status (struct thread_info
*tp
,
5528 && tp
->suspend
.waitstatus_pending_p
);
5531 /* Called when we get an event that may finish an in-line or
5532 out-of-line (displaced stepping) step-over started previously.
5533 Return true if the event is processed and we should go back to the
5534 event loop; false if the caller should continue processing the
5538 finish_step_over (struct execution_control_state
*ecs
)
5540 int had_step_over_info
;
5542 displaced_step_fixup (ecs
->ptid
,
5543 ecs
->event_thread
->suspend
.stop_signal
);
5545 had_step_over_info
= step_over_info_valid_p ();
5547 if (had_step_over_info
)
5549 /* If we're stepping over a breakpoint with all threads locked,
5550 then only the thread that was stepped should be reporting
5552 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5554 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5555 clear_step_over_info ();
5558 if (!target_is_non_stop_p ())
5561 /* Start a new step-over in another thread if there's one that
5565 /* If we were stepping over a breakpoint before, and haven't started
5566 a new in-line step-over sequence, then restart all other threads
5567 (except the event thread). We can't do this in all-stop, as then
5568 e.g., we wouldn't be able to issue any other remote packet until
5569 these other threads stop. */
5570 if (had_step_over_info
&& !step_over_info_valid_p ())
5572 struct thread_info
*pending
;
5574 /* If we only have threads with pending statuses, the restart
5575 below won't restart any thread and so nothing re-inserts the
5576 breakpoint we just stepped over. But we need it inserted
5577 when we later process the pending events, otherwise if
5578 another thread has a pending event for this breakpoint too,
5579 we'd discard its event (because the breakpoint that
5580 originally caused the event was no longer inserted). */
5581 context_switch (ecs
->ptid
);
5582 insert_breakpoints ();
5584 restart_threads (ecs
->event_thread
);
5586 /* If we have events pending, go through handle_inferior_event
5587 again, picking up a pending event at random. This avoids
5588 thread starvation. */
5590 /* But not if we just stepped over a watchpoint in order to let
5591 the instruction execute so we can evaluate its expression.
5592 The set of watchpoints that triggered is recorded in the
5593 breakpoint objects themselves (see bp->watchpoint_triggered).
5594 If we processed another event first, that other event could
5595 clobber this info. */
5596 if (ecs
->event_thread
->stepping_over_watchpoint
)
5599 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5601 if (pending
!= NULL
)
5603 struct thread_info
*tp
= ecs
->event_thread
;
5604 struct regcache
*regcache
;
5608 fprintf_unfiltered (gdb_stdlog
,
5609 "infrun: found resumed threads with "
5610 "pending events, saving status\n");
5613 gdb_assert (pending
!= tp
);
5615 /* Record the event thread's event for later. */
5616 save_waitstatus (tp
, &ecs
->ws
);
5617 /* This was cleared early, by handle_inferior_event. Set it
5618 so this pending event is considered by
5622 gdb_assert (!tp
->executing
);
5624 regcache
= get_thread_regcache (tp
->ptid
);
5625 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5629 fprintf_unfiltered (gdb_stdlog
,
5630 "infrun: saved stop_pc=%s for %s "
5631 "(currently_stepping=%d)\n",
5632 paddress (target_gdbarch (),
5633 tp
->suspend
.stop_pc
),
5634 target_pid_to_str (tp
->ptid
),
5635 currently_stepping (tp
));
5638 /* This in-line step-over finished; clear this so we won't
5639 start a new one. This is what handle_signal_stop would
5640 do, if we returned false. */
5641 tp
->stepping_over_breakpoint
= 0;
5643 /* Wake up the event loop again. */
5644 mark_async_event_handler (infrun_async_inferior_event_token
);
5646 prepare_to_wait (ecs
);
5654 /* Come here when the program has stopped with a signal. */
5657 handle_signal_stop (struct execution_control_state
*ecs
)
5659 struct frame_info
*frame
;
5660 struct gdbarch
*gdbarch
;
5661 int stopped_by_watchpoint
;
5662 enum stop_kind stop_soon
;
5665 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5667 /* Do we need to clean up the state of a thread that has
5668 completed a displaced single-step? (Doing so usually affects
5669 the PC, so do it here, before we set stop_pc.) */
5670 if (finish_step_over (ecs
))
5673 /* If we either finished a single-step or hit a breakpoint, but
5674 the user wanted this thread to be stopped, pretend we got a
5675 SIG0 (generic unsignaled stop). */
5676 if (ecs
->event_thread
->stop_requested
5677 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5678 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5680 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5684 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5685 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5686 struct cleanup
*old_chain
= save_inferior_ptid ();
5688 inferior_ptid
= ecs
->ptid
;
5690 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5691 paddress (gdbarch
, stop_pc
));
5692 if (target_stopped_by_watchpoint ())
5696 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5698 if (target_stopped_data_address (¤t_target
, &addr
))
5699 fprintf_unfiltered (gdb_stdlog
,
5700 "infrun: stopped data address = %s\n",
5701 paddress (gdbarch
, addr
));
5703 fprintf_unfiltered (gdb_stdlog
,
5704 "infrun: (no data address available)\n");
5707 do_cleanups (old_chain
);
5710 /* This is originated from start_remote(), start_inferior() and
5711 shared libraries hook functions. */
5712 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5713 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5715 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5716 context_switch (ecs
->ptid
);
5718 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5719 stop_print_frame
= 1;
5724 /* This originates from attach_command(). We need to overwrite
5725 the stop_signal here, because some kernels don't ignore a
5726 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5727 See more comments in inferior.h. On the other hand, if we
5728 get a non-SIGSTOP, report it to the user - assume the backend
5729 will handle the SIGSTOP if it should show up later.
5731 Also consider that the attach is complete when we see a
5732 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5733 target extended-remote report it instead of a SIGSTOP
5734 (e.g. gdbserver). We already rely on SIGTRAP being our
5735 signal, so this is no exception.
5737 Also consider that the attach is complete when we see a
5738 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5739 the target to stop all threads of the inferior, in case the
5740 low level attach operation doesn't stop them implicitly. If
5741 they weren't stopped implicitly, then the stub will report a
5742 GDB_SIGNAL_0, meaning: stopped for no particular reason
5743 other than GDB's request. */
5744 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5745 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5746 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5747 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5749 stop_print_frame
= 1;
5751 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5755 /* See if something interesting happened to the non-current thread. If
5756 so, then switch to that thread. */
5757 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5760 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5762 context_switch (ecs
->ptid
);
5764 if (deprecated_context_hook
)
5765 deprecated_context_hook (ptid_to_global_thread_id (ecs
->ptid
));
5768 /* At this point, get hold of the now-current thread's frame. */
5769 frame
= get_current_frame ();
5770 gdbarch
= get_frame_arch (frame
);
5772 /* Pull the single step breakpoints out of the target. */
5773 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5775 struct regcache
*regcache
;
5776 struct address_space
*aspace
;
5779 regcache
= get_thread_regcache (ecs
->ptid
);
5780 aspace
= get_regcache_aspace (regcache
);
5781 pc
= regcache_read_pc (regcache
);
5783 /* However, before doing so, if this single-step breakpoint was
5784 actually for another thread, set this thread up for moving
5786 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5789 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5793 fprintf_unfiltered (gdb_stdlog
,
5794 "infrun: [%s] hit another thread's "
5795 "single-step breakpoint\n",
5796 target_pid_to_str (ecs
->ptid
));
5798 ecs
->hit_singlestep_breakpoint
= 1;
5805 fprintf_unfiltered (gdb_stdlog
,
5806 "infrun: [%s] hit its "
5807 "single-step breakpoint\n",
5808 target_pid_to_str (ecs
->ptid
));
5812 delete_just_stopped_threads_single_step_breakpoints ();
5814 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5815 && ecs
->event_thread
->control
.trap_expected
5816 && ecs
->event_thread
->stepping_over_watchpoint
)
5817 stopped_by_watchpoint
= 0;
5819 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5821 /* If necessary, step over this watchpoint. We'll be back to display
5823 if (stopped_by_watchpoint
5824 && (target_have_steppable_watchpoint
5825 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5827 /* At this point, we are stopped at an instruction which has
5828 attempted to write to a piece of memory under control of
5829 a watchpoint. The instruction hasn't actually executed
5830 yet. If we were to evaluate the watchpoint expression
5831 now, we would get the old value, and therefore no change
5832 would seem to have occurred.
5834 In order to make watchpoints work `right', we really need
5835 to complete the memory write, and then evaluate the
5836 watchpoint expression. We do this by single-stepping the
5839 It may not be necessary to disable the watchpoint to step over
5840 it. For example, the PA can (with some kernel cooperation)
5841 single step over a watchpoint without disabling the watchpoint.
5843 It is far more common to need to disable a watchpoint to step
5844 the inferior over it. If we have non-steppable watchpoints,
5845 we must disable the current watchpoint; it's simplest to
5846 disable all watchpoints.
5848 Any breakpoint at PC must also be stepped over -- if there's
5849 one, it will have already triggered before the watchpoint
5850 triggered, and we either already reported it to the user, or
5851 it didn't cause a stop and we called keep_going. In either
5852 case, if there was a breakpoint at PC, we must be trying to
5854 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5859 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5860 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5861 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5862 ecs
->event_thread
->control
.stop_step
= 0;
5863 stop_print_frame
= 1;
5864 stopped_by_random_signal
= 0;
5866 /* Hide inlined functions starting here, unless we just performed stepi or
5867 nexti. After stepi and nexti, always show the innermost frame (not any
5868 inline function call sites). */
5869 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5871 struct address_space
*aspace
=
5872 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5874 /* skip_inline_frames is expensive, so we avoid it if we can
5875 determine that the address is one where functions cannot have
5876 been inlined. This improves performance with inferiors that
5877 load a lot of shared libraries, because the solib event
5878 breakpoint is defined as the address of a function (i.e. not
5879 inline). Note that we have to check the previous PC as well
5880 as the current one to catch cases when we have just
5881 single-stepped off a breakpoint prior to reinstating it.
5882 Note that we're assuming that the code we single-step to is
5883 not inline, but that's not definitive: there's nothing
5884 preventing the event breakpoint function from containing
5885 inlined code, and the single-step ending up there. If the
5886 user had set a breakpoint on that inlined code, the missing
5887 skip_inline_frames call would break things. Fortunately
5888 that's an extremely unlikely scenario. */
5889 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5890 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5891 && ecs
->event_thread
->control
.trap_expected
5892 && pc_at_non_inline_function (aspace
,
5893 ecs
->event_thread
->prev_pc
,
5896 skip_inline_frames (ecs
->ptid
);
5898 /* Re-fetch current thread's frame in case that invalidated
5900 frame
= get_current_frame ();
5901 gdbarch
= get_frame_arch (frame
);
5905 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5906 && ecs
->event_thread
->control
.trap_expected
5907 && gdbarch_single_step_through_delay_p (gdbarch
)
5908 && currently_stepping (ecs
->event_thread
))
5910 /* We're trying to step off a breakpoint. Turns out that we're
5911 also on an instruction that needs to be stepped multiple
5912 times before it's been fully executing. E.g., architectures
5913 with a delay slot. It needs to be stepped twice, once for
5914 the instruction and once for the delay slot. */
5915 int step_through_delay
5916 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5918 if (debug_infrun
&& step_through_delay
)
5919 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5920 if (ecs
->event_thread
->control
.step_range_end
== 0
5921 && step_through_delay
)
5923 /* The user issued a continue when stopped at a breakpoint.
5924 Set up for another trap and get out of here. */
5925 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5929 else if (step_through_delay
)
5931 /* The user issued a step when stopped at a breakpoint.
5932 Maybe we should stop, maybe we should not - the delay
5933 slot *might* correspond to a line of source. In any
5934 case, don't decide that here, just set
5935 ecs->stepping_over_breakpoint, making sure we
5936 single-step again before breakpoints are re-inserted. */
5937 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5941 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5942 handles this event. */
5943 ecs
->event_thread
->control
.stop_bpstat
5944 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5945 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5947 /* Following in case break condition called a
5949 stop_print_frame
= 1;
5951 /* This is where we handle "moribund" watchpoints. Unlike
5952 software breakpoints traps, hardware watchpoint traps are
5953 always distinguishable from random traps. If no high-level
5954 watchpoint is associated with the reported stop data address
5955 anymore, then the bpstat does not explain the signal ---
5956 simply make sure to ignore it if `stopped_by_watchpoint' is
5960 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5961 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5963 && stopped_by_watchpoint
)
5964 fprintf_unfiltered (gdb_stdlog
,
5965 "infrun: no user watchpoint explains "
5966 "watchpoint SIGTRAP, ignoring\n");
5968 /* NOTE: cagney/2003-03-29: These checks for a random signal
5969 at one stage in the past included checks for an inferior
5970 function call's call dummy's return breakpoint. The original
5971 comment, that went with the test, read:
5973 ``End of a stack dummy. Some systems (e.g. Sony news) give
5974 another signal besides SIGTRAP, so check here as well as
5977 If someone ever tries to get call dummys on a
5978 non-executable stack to work (where the target would stop
5979 with something like a SIGSEGV), then those tests might need
5980 to be re-instated. Given, however, that the tests were only
5981 enabled when momentary breakpoints were not being used, I
5982 suspect that it won't be the case.
5984 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5985 be necessary for call dummies on a non-executable stack on
5988 /* See if the breakpoints module can explain the signal. */
5990 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5991 ecs
->event_thread
->suspend
.stop_signal
);
5993 /* Maybe this was a trap for a software breakpoint that has since
5995 if (random_signal
&& target_stopped_by_sw_breakpoint ())
5997 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
5999 struct regcache
*regcache
;
6002 /* Re-adjust PC to what the program would see if GDB was not
6004 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
6005 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6008 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
6010 if (record_full_is_used ())
6011 record_full_gdb_operation_disable_set ();
6013 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
6015 do_cleanups (old_cleanups
);
6020 /* A delayed software breakpoint event. Ignore the trap. */
6022 fprintf_unfiltered (gdb_stdlog
,
6023 "infrun: delayed software breakpoint "
6024 "trap, ignoring\n");
6029 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6030 has since been removed. */
6031 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6033 /* A delayed hardware breakpoint event. Ignore the trap. */
6035 fprintf_unfiltered (gdb_stdlog
,
6036 "infrun: delayed hardware breakpoint/watchpoint "
6037 "trap, ignoring\n");
6041 /* If not, perhaps stepping/nexting can. */
6043 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6044 && currently_stepping (ecs
->event_thread
));
6046 /* Perhaps the thread hit a single-step breakpoint of _another_
6047 thread. Single-step breakpoints are transparent to the
6048 breakpoints module. */
6050 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6052 /* No? Perhaps we got a moribund watchpoint. */
6054 random_signal
= !stopped_by_watchpoint
;
6056 /* For the program's own signals, act according to
6057 the signal handling tables. */
6061 /* Signal not for debugging purposes. */
6062 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
6063 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6066 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
6067 gdb_signal_to_symbol_string (stop_signal
));
6069 stopped_by_random_signal
= 1;
6071 /* Always stop on signals if we're either just gaining control
6072 of the program, or the user explicitly requested this thread
6073 to remain stopped. */
6074 if (stop_soon
!= NO_STOP_QUIETLY
6075 || ecs
->event_thread
->stop_requested
6077 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
6083 /* Notify observers the signal has "handle print" set. Note we
6084 returned early above if stopping; normal_stop handles the
6085 printing in that case. */
6086 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6088 /* The signal table tells us to print about this signal. */
6089 target_terminal_ours_for_output ();
6090 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
6091 target_terminal_inferior ();
6094 /* Clear the signal if it should not be passed. */
6095 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6096 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6098 if (ecs
->event_thread
->prev_pc
== stop_pc
6099 && ecs
->event_thread
->control
.trap_expected
6100 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6104 /* We were just starting a new sequence, attempting to
6105 single-step off of a breakpoint and expecting a SIGTRAP.
6106 Instead this signal arrives. This signal will take us out
6107 of the stepping range so GDB needs to remember to, when
6108 the signal handler returns, resume stepping off that
6110 /* To simplify things, "continue" is forced to use the same
6111 code paths as single-step - set a breakpoint at the
6112 signal return address and then, once hit, step off that
6115 fprintf_unfiltered (gdb_stdlog
,
6116 "infrun: signal arrived while stepping over "
6119 was_in_line
= step_over_info_valid_p ();
6120 clear_step_over_info ();
6121 insert_hp_step_resume_breakpoint_at_frame (frame
);
6122 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6123 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6124 ecs
->event_thread
->control
.trap_expected
= 0;
6126 if (target_is_non_stop_p ())
6128 /* Either "set non-stop" is "on", or the target is
6129 always in non-stop mode. In this case, we have a bit
6130 more work to do. Resume the current thread, and if
6131 we had paused all threads, restart them while the
6132 signal handler runs. */
6137 restart_threads (ecs
->event_thread
);
6139 else if (debug_infrun
)
6141 fprintf_unfiltered (gdb_stdlog
,
6142 "infrun: no need to restart threads\n");
6147 /* If we were nexting/stepping some other thread, switch to
6148 it, so that we don't continue it, losing control. */
6149 if (!switch_back_to_stepped_thread (ecs
))
6154 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6155 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6156 || ecs
->event_thread
->control
.step_range_end
== 1)
6157 && frame_id_eq (get_stack_frame_id (frame
),
6158 ecs
->event_thread
->control
.step_stack_frame_id
)
6159 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6161 /* The inferior is about to take a signal that will take it
6162 out of the single step range. Set a breakpoint at the
6163 current PC (which is presumably where the signal handler
6164 will eventually return) and then allow the inferior to
6167 Note that this is only needed for a signal delivered
6168 while in the single-step range. Nested signals aren't a
6169 problem as they eventually all return. */
6171 fprintf_unfiltered (gdb_stdlog
,
6172 "infrun: signal may take us out of "
6173 "single-step range\n");
6175 clear_step_over_info ();
6176 insert_hp_step_resume_breakpoint_at_frame (frame
);
6177 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6178 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6179 ecs
->event_thread
->control
.trap_expected
= 0;
6184 /* Note: step_resume_breakpoint may be non-NULL. This occures
6185 when either there's a nested signal, or when there's a
6186 pending signal enabled just as the signal handler returns
6187 (leaving the inferior at the step-resume-breakpoint without
6188 actually executing it). Either way continue until the
6189 breakpoint is really hit. */
6191 if (!switch_back_to_stepped_thread (ecs
))
6194 fprintf_unfiltered (gdb_stdlog
,
6195 "infrun: random signal, keep going\n");
6202 process_event_stop_test (ecs
);
6205 /* Come here when we've got some debug event / signal we can explain
6206 (IOW, not a random signal), and test whether it should cause a
6207 stop, or whether we should resume the inferior (transparently).
6208 E.g., could be a breakpoint whose condition evaluates false; we
6209 could be still stepping within the line; etc. */
6212 process_event_stop_test (struct execution_control_state
*ecs
)
6214 struct symtab_and_line stop_pc_sal
;
6215 struct frame_info
*frame
;
6216 struct gdbarch
*gdbarch
;
6217 CORE_ADDR jmp_buf_pc
;
6218 struct bpstat_what what
;
6220 /* Handle cases caused by hitting a breakpoint. */
6222 frame
= get_current_frame ();
6223 gdbarch
= get_frame_arch (frame
);
6225 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6227 if (what
.call_dummy
)
6229 stop_stack_dummy
= what
.call_dummy
;
6232 /* A few breakpoint types have callbacks associated (e.g.,
6233 bp_jit_event). Run them now. */
6234 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6236 /* If we hit an internal event that triggers symbol changes, the
6237 current frame will be invalidated within bpstat_what (e.g., if we
6238 hit an internal solib event). Re-fetch it. */
6239 frame
= get_current_frame ();
6240 gdbarch
= get_frame_arch (frame
);
6242 switch (what
.main_action
)
6244 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6245 /* If we hit the breakpoint at longjmp while stepping, we
6246 install a momentary breakpoint at the target of the
6250 fprintf_unfiltered (gdb_stdlog
,
6251 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6253 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6255 if (what
.is_longjmp
)
6257 struct value
*arg_value
;
6259 /* If we set the longjmp breakpoint via a SystemTap probe,
6260 then use it to extract the arguments. The destination PC
6261 is the third argument to the probe. */
6262 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6265 jmp_buf_pc
= value_as_address (arg_value
);
6266 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6268 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6269 || !gdbarch_get_longjmp_target (gdbarch
,
6270 frame
, &jmp_buf_pc
))
6273 fprintf_unfiltered (gdb_stdlog
,
6274 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6275 "(!gdbarch_get_longjmp_target)\n");
6280 /* Insert a breakpoint at resume address. */
6281 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6284 check_exception_resume (ecs
, frame
);
6288 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6290 struct frame_info
*init_frame
;
6292 /* There are several cases to consider.
6294 1. The initiating frame no longer exists. In this case we
6295 must stop, because the exception or longjmp has gone too
6298 2. The initiating frame exists, and is the same as the
6299 current frame. We stop, because the exception or longjmp
6302 3. The initiating frame exists and is different from the
6303 current frame. This means the exception or longjmp has
6304 been caught beneath the initiating frame, so keep going.
6306 4. longjmp breakpoint has been placed just to protect
6307 against stale dummy frames and user is not interested in
6308 stopping around longjmps. */
6311 fprintf_unfiltered (gdb_stdlog
,
6312 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6314 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6316 delete_exception_resume_breakpoint (ecs
->event_thread
);
6318 if (what
.is_longjmp
)
6320 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6322 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6330 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6334 struct frame_id current_id
6335 = get_frame_id (get_current_frame ());
6336 if (frame_id_eq (current_id
,
6337 ecs
->event_thread
->initiating_frame
))
6339 /* Case 2. Fall through. */
6349 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6351 delete_step_resume_breakpoint (ecs
->event_thread
);
6353 end_stepping_range (ecs
);
6357 case BPSTAT_WHAT_SINGLE
:
6359 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6360 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6361 /* Still need to check other stuff, at least the case where we
6362 are stepping and step out of the right range. */
6365 case BPSTAT_WHAT_STEP_RESUME
:
6367 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6369 delete_step_resume_breakpoint (ecs
->event_thread
);
6370 if (ecs
->event_thread
->control
.proceed_to_finish
6371 && execution_direction
== EXEC_REVERSE
)
6373 struct thread_info
*tp
= ecs
->event_thread
;
6375 /* We are finishing a function in reverse, and just hit the
6376 step-resume breakpoint at the start address of the
6377 function, and we're almost there -- just need to back up
6378 by one more single-step, which should take us back to the
6380 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6384 fill_in_stop_func (gdbarch
, ecs
);
6385 if (stop_pc
== ecs
->stop_func_start
6386 && execution_direction
== EXEC_REVERSE
)
6388 /* We are stepping over a function call in reverse, and just
6389 hit the step-resume breakpoint at the start address of
6390 the function. Go back to single-stepping, which should
6391 take us back to the function call. */
6392 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6398 case BPSTAT_WHAT_STOP_NOISY
:
6400 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6401 stop_print_frame
= 1;
6403 /* Assume the thread stopped for a breapoint. We'll still check
6404 whether a/the breakpoint is there when the thread is next
6406 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6411 case BPSTAT_WHAT_STOP_SILENT
:
6413 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6414 stop_print_frame
= 0;
6416 /* Assume the thread stopped for a breapoint. We'll still check
6417 whether a/the breakpoint is there when the thread is next
6419 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6423 case BPSTAT_WHAT_HP_STEP_RESUME
:
6425 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6427 delete_step_resume_breakpoint (ecs
->event_thread
);
6428 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6430 /* Back when the step-resume breakpoint was inserted, we
6431 were trying to single-step off a breakpoint. Go back to
6433 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6434 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6440 case BPSTAT_WHAT_KEEP_CHECKING
:
6444 /* If we stepped a permanent breakpoint and we had a high priority
6445 step-resume breakpoint for the address we stepped, but we didn't
6446 hit it, then we must have stepped into the signal handler. The
6447 step-resume was only necessary to catch the case of _not_
6448 stepping into the handler, so delete it, and fall through to
6449 checking whether the step finished. */
6450 if (ecs
->event_thread
->stepped_breakpoint
)
6452 struct breakpoint
*sr_bp
6453 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6456 && sr_bp
->loc
->permanent
6457 && sr_bp
->type
== bp_hp_step_resume
6458 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6461 fprintf_unfiltered (gdb_stdlog
,
6462 "infrun: stepped permanent breakpoint, stopped in "
6464 delete_step_resume_breakpoint (ecs
->event_thread
);
6465 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6469 /* We come here if we hit a breakpoint but should not stop for it.
6470 Possibly we also were stepping and should stop for that. So fall
6471 through and test for stepping. But, if not stepping, do not
6474 /* In all-stop mode, if we're currently stepping but have stopped in
6475 some other thread, we need to switch back to the stepped thread. */
6476 if (switch_back_to_stepped_thread (ecs
))
6479 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6482 fprintf_unfiltered (gdb_stdlog
,
6483 "infrun: step-resume breakpoint is inserted\n");
6485 /* Having a step-resume breakpoint overrides anything
6486 else having to do with stepping commands until
6487 that breakpoint is reached. */
6492 if (ecs
->event_thread
->control
.step_range_end
== 0)
6495 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6496 /* Likewise if we aren't even stepping. */
6501 /* Re-fetch current thread's frame in case the code above caused
6502 the frame cache to be re-initialized, making our FRAME variable
6503 a dangling pointer. */
6504 frame
= get_current_frame ();
6505 gdbarch
= get_frame_arch (frame
);
6506 fill_in_stop_func (gdbarch
, ecs
);
6508 /* If stepping through a line, keep going if still within it.
6510 Note that step_range_end is the address of the first instruction
6511 beyond the step range, and NOT the address of the last instruction
6514 Note also that during reverse execution, we may be stepping
6515 through a function epilogue and therefore must detect when
6516 the current-frame changes in the middle of a line. */
6518 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6519 && (execution_direction
!= EXEC_REVERSE
6520 || frame_id_eq (get_frame_id (frame
),
6521 ecs
->event_thread
->control
.step_frame_id
)))
6525 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6526 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6527 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6529 /* Tentatively re-enable range stepping; `resume' disables it if
6530 necessary (e.g., if we're stepping over a breakpoint or we
6531 have software watchpoints). */
6532 ecs
->event_thread
->control
.may_range_step
= 1;
6534 /* When stepping backward, stop at beginning of line range
6535 (unless it's the function entry point, in which case
6536 keep going back to the call point). */
6537 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6538 && stop_pc
!= ecs
->stop_func_start
6539 && execution_direction
== EXEC_REVERSE
)
6540 end_stepping_range (ecs
);
6547 /* We stepped out of the stepping range. */
6549 /* If we are stepping at the source level and entered the runtime
6550 loader dynamic symbol resolution code...
6552 EXEC_FORWARD: we keep on single stepping until we exit the run
6553 time loader code and reach the callee's address.
6555 EXEC_REVERSE: we've already executed the callee (backward), and
6556 the runtime loader code is handled just like any other
6557 undebuggable function call. Now we need only keep stepping
6558 backward through the trampoline code, and that's handled further
6559 down, so there is nothing for us to do here. */
6561 if (execution_direction
!= EXEC_REVERSE
6562 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6563 && in_solib_dynsym_resolve_code (stop_pc
))
6565 CORE_ADDR pc_after_resolver
=
6566 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6569 fprintf_unfiltered (gdb_stdlog
,
6570 "infrun: stepped into dynsym resolve code\n");
6572 if (pc_after_resolver
)
6574 /* Set up a step-resume breakpoint at the address
6575 indicated by SKIP_SOLIB_RESOLVER. */
6576 struct symtab_and_line sr_sal
;
6579 sr_sal
.pc
= pc_after_resolver
;
6580 sr_sal
.pspace
= get_frame_program_space (frame
);
6582 insert_step_resume_breakpoint_at_sal (gdbarch
,
6583 sr_sal
, null_frame_id
);
6590 if (ecs
->event_thread
->control
.step_range_end
!= 1
6591 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6592 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6593 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6596 fprintf_unfiltered (gdb_stdlog
,
6597 "infrun: stepped into signal trampoline\n");
6598 /* The inferior, while doing a "step" or "next", has ended up in
6599 a signal trampoline (either by a signal being delivered or by
6600 the signal handler returning). Just single-step until the
6601 inferior leaves the trampoline (either by calling the handler
6607 /* If we're in the return path from a shared library trampoline,
6608 we want to proceed through the trampoline when stepping. */
6609 /* macro/2012-04-25: This needs to come before the subroutine
6610 call check below as on some targets return trampolines look
6611 like subroutine calls (MIPS16 return thunks). */
6612 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6613 stop_pc
, ecs
->stop_func_name
)
6614 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6616 /* Determine where this trampoline returns. */
6617 CORE_ADDR real_stop_pc
;
6619 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6622 fprintf_unfiltered (gdb_stdlog
,
6623 "infrun: stepped into solib return tramp\n");
6625 /* Only proceed through if we know where it's going. */
6628 /* And put the step-breakpoint there and go until there. */
6629 struct symtab_and_line sr_sal
;
6631 init_sal (&sr_sal
); /* initialize to zeroes */
6632 sr_sal
.pc
= real_stop_pc
;
6633 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6634 sr_sal
.pspace
= get_frame_program_space (frame
);
6636 /* Do not specify what the fp should be when we stop since
6637 on some machines the prologue is where the new fp value
6639 insert_step_resume_breakpoint_at_sal (gdbarch
,
6640 sr_sal
, null_frame_id
);
6642 /* Restart without fiddling with the step ranges or
6649 /* Check for subroutine calls. The check for the current frame
6650 equalling the step ID is not necessary - the check of the
6651 previous frame's ID is sufficient - but it is a common case and
6652 cheaper than checking the previous frame's ID.
6654 NOTE: frame_id_eq will never report two invalid frame IDs as
6655 being equal, so to get into this block, both the current and
6656 previous frame must have valid frame IDs. */
6657 /* The outer_frame_id check is a heuristic to detect stepping
6658 through startup code. If we step over an instruction which
6659 sets the stack pointer from an invalid value to a valid value,
6660 we may detect that as a subroutine call from the mythical
6661 "outermost" function. This could be fixed by marking
6662 outermost frames as !stack_p,code_p,special_p. Then the
6663 initial outermost frame, before sp was valid, would
6664 have code_addr == &_start. See the comment in frame_id_eq
6666 if (!frame_id_eq (get_stack_frame_id (frame
),
6667 ecs
->event_thread
->control
.step_stack_frame_id
)
6668 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6669 ecs
->event_thread
->control
.step_stack_frame_id
)
6670 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6672 || (ecs
->event_thread
->control
.step_start_function
6673 != find_pc_function (stop_pc
)))))
6675 CORE_ADDR real_stop_pc
;
6678 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6680 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6682 /* I presume that step_over_calls is only 0 when we're
6683 supposed to be stepping at the assembly language level
6684 ("stepi"). Just stop. */
6685 /* And this works the same backward as frontward. MVS */
6686 end_stepping_range (ecs
);
6690 /* Reverse stepping through solib trampolines. */
6692 if (execution_direction
== EXEC_REVERSE
6693 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6694 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6695 || (ecs
->stop_func_start
== 0
6696 && in_solib_dynsym_resolve_code (stop_pc
))))
6698 /* Any solib trampoline code can be handled in reverse
6699 by simply continuing to single-step. We have already
6700 executed the solib function (backwards), and a few
6701 steps will take us back through the trampoline to the
6707 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6709 /* We're doing a "next".
6711 Normal (forward) execution: set a breakpoint at the
6712 callee's return address (the address at which the caller
6715 Reverse (backward) execution. set the step-resume
6716 breakpoint at the start of the function that we just
6717 stepped into (backwards), and continue to there. When we
6718 get there, we'll need to single-step back to the caller. */
6720 if (execution_direction
== EXEC_REVERSE
)
6722 /* If we're already at the start of the function, we've either
6723 just stepped backward into a single instruction function,
6724 or stepped back out of a signal handler to the first instruction
6725 of the function. Just keep going, which will single-step back
6727 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6729 struct symtab_and_line sr_sal
;
6731 /* Normal function call return (static or dynamic). */
6733 sr_sal
.pc
= ecs
->stop_func_start
;
6734 sr_sal
.pspace
= get_frame_program_space (frame
);
6735 insert_step_resume_breakpoint_at_sal (gdbarch
,
6736 sr_sal
, null_frame_id
);
6740 insert_step_resume_breakpoint_at_caller (frame
);
6746 /* If we are in a function call trampoline (a stub between the
6747 calling routine and the real function), locate the real
6748 function. That's what tells us (a) whether we want to step
6749 into it at all, and (b) what prologue we want to run to the
6750 end of, if we do step into it. */
6751 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6752 if (real_stop_pc
== 0)
6753 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6754 if (real_stop_pc
!= 0)
6755 ecs
->stop_func_start
= real_stop_pc
;
6757 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6759 struct symtab_and_line sr_sal
;
6762 sr_sal
.pc
= ecs
->stop_func_start
;
6763 sr_sal
.pspace
= get_frame_program_space (frame
);
6765 insert_step_resume_breakpoint_at_sal (gdbarch
,
6766 sr_sal
, null_frame_id
);
6771 /* If we have line number information for the function we are
6772 thinking of stepping into and the function isn't on the skip
6775 If there are several symtabs at that PC (e.g. with include
6776 files), just want to know whether *any* of them have line
6777 numbers. find_pc_line handles this. */
6779 struct symtab_and_line tmp_sal
;
6781 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6782 if (tmp_sal
.line
!= 0
6783 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6786 if (execution_direction
== EXEC_REVERSE
)
6787 handle_step_into_function_backward (gdbarch
, ecs
);
6789 handle_step_into_function (gdbarch
, ecs
);
6794 /* If we have no line number and the step-stop-if-no-debug is
6795 set, we stop the step so that the user has a chance to switch
6796 in assembly mode. */
6797 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6798 && step_stop_if_no_debug
)
6800 end_stepping_range (ecs
);
6804 if (execution_direction
== EXEC_REVERSE
)
6806 /* If we're already at the start of the function, we've either just
6807 stepped backward into a single instruction function without line
6808 number info, or stepped back out of a signal handler to the first
6809 instruction of the function without line number info. Just keep
6810 going, which will single-step back to the caller. */
6811 if (ecs
->stop_func_start
!= stop_pc
)
6813 /* Set a breakpoint at callee's start address.
6814 From there we can step once and be back in the caller. */
6815 struct symtab_and_line sr_sal
;
6818 sr_sal
.pc
= ecs
->stop_func_start
;
6819 sr_sal
.pspace
= get_frame_program_space (frame
);
6820 insert_step_resume_breakpoint_at_sal (gdbarch
,
6821 sr_sal
, null_frame_id
);
6825 /* Set a breakpoint at callee's return address (the address
6826 at which the caller will resume). */
6827 insert_step_resume_breakpoint_at_caller (frame
);
6833 /* Reverse stepping through solib trampolines. */
6835 if (execution_direction
== EXEC_REVERSE
6836 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6838 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6839 || (ecs
->stop_func_start
== 0
6840 && in_solib_dynsym_resolve_code (stop_pc
)))
6842 /* Any solib trampoline code can be handled in reverse
6843 by simply continuing to single-step. We have already
6844 executed the solib function (backwards), and a few
6845 steps will take us back through the trampoline to the
6850 else if (in_solib_dynsym_resolve_code (stop_pc
))
6852 /* Stepped backward into the solib dynsym resolver.
6853 Set a breakpoint at its start and continue, then
6854 one more step will take us out. */
6855 struct symtab_and_line sr_sal
;
6858 sr_sal
.pc
= ecs
->stop_func_start
;
6859 sr_sal
.pspace
= get_frame_program_space (frame
);
6860 insert_step_resume_breakpoint_at_sal (gdbarch
,
6861 sr_sal
, null_frame_id
);
6867 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6869 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6870 the trampoline processing logic, however, there are some trampolines
6871 that have no names, so we should do trampoline handling first. */
6872 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6873 && ecs
->stop_func_name
== NULL
6874 && stop_pc_sal
.line
== 0)
6877 fprintf_unfiltered (gdb_stdlog
,
6878 "infrun: stepped into undebuggable function\n");
6880 /* The inferior just stepped into, or returned to, an
6881 undebuggable function (where there is no debugging information
6882 and no line number corresponding to the address where the
6883 inferior stopped). Since we want to skip this kind of code,
6884 we keep going until the inferior returns from this
6885 function - unless the user has asked us not to (via
6886 set step-mode) or we no longer know how to get back
6887 to the call site. */
6888 if (step_stop_if_no_debug
6889 || !frame_id_p (frame_unwind_caller_id (frame
)))
6891 /* If we have no line number and the step-stop-if-no-debug
6892 is set, we stop the step so that the user has a chance to
6893 switch in assembly mode. */
6894 end_stepping_range (ecs
);
6899 /* Set a breakpoint at callee's return address (the address
6900 at which the caller will resume). */
6901 insert_step_resume_breakpoint_at_caller (frame
);
6907 if (ecs
->event_thread
->control
.step_range_end
== 1)
6909 /* It is stepi or nexti. We always want to stop stepping after
6912 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6913 end_stepping_range (ecs
);
6917 if (stop_pc_sal
.line
== 0)
6919 /* We have no line number information. That means to stop
6920 stepping (does this always happen right after one instruction,
6921 when we do "s" in a function with no line numbers,
6922 or can this happen as a result of a return or longjmp?). */
6924 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6925 end_stepping_range (ecs
);
6929 /* Look for "calls" to inlined functions, part one. If the inline
6930 frame machinery detected some skipped call sites, we have entered
6931 a new inline function. */
6933 if (frame_id_eq (get_frame_id (get_current_frame ()),
6934 ecs
->event_thread
->control
.step_frame_id
)
6935 && inline_skipped_frames (ecs
->ptid
))
6937 struct symtab_and_line call_sal
;
6940 fprintf_unfiltered (gdb_stdlog
,
6941 "infrun: stepped into inlined function\n");
6943 find_frame_sal (get_current_frame (), &call_sal
);
6945 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6947 /* For "step", we're going to stop. But if the call site
6948 for this inlined function is on the same source line as
6949 we were previously stepping, go down into the function
6950 first. Otherwise stop at the call site. */
6952 if (call_sal
.line
== ecs
->event_thread
->current_line
6953 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6954 step_into_inline_frame (ecs
->ptid
);
6956 end_stepping_range (ecs
);
6961 /* For "next", we should stop at the call site if it is on a
6962 different source line. Otherwise continue through the
6963 inlined function. */
6964 if (call_sal
.line
== ecs
->event_thread
->current_line
6965 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6968 end_stepping_range (ecs
);
6973 /* Look for "calls" to inlined functions, part two. If we are still
6974 in the same real function we were stepping through, but we have
6975 to go further up to find the exact frame ID, we are stepping
6976 through a more inlined call beyond its call site. */
6978 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6979 && !frame_id_eq (get_frame_id (get_current_frame ()),
6980 ecs
->event_thread
->control
.step_frame_id
)
6981 && stepped_in_from (get_current_frame (),
6982 ecs
->event_thread
->control
.step_frame_id
))
6985 fprintf_unfiltered (gdb_stdlog
,
6986 "infrun: stepping through inlined function\n");
6988 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6991 end_stepping_range (ecs
);
6995 if ((stop_pc
== stop_pc_sal
.pc
)
6996 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6997 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6999 /* We are at the start of a different line. So stop. Note that
7000 we don't stop if we step into the middle of a different line.
7001 That is said to make things like for (;;) statements work
7004 fprintf_unfiltered (gdb_stdlog
,
7005 "infrun: stepped to a different line\n");
7006 end_stepping_range (ecs
);
7010 /* We aren't done stepping.
7012 Optimize by setting the stepping range to the line.
7013 (We might not be in the original line, but if we entered a
7014 new line in mid-statement, we continue stepping. This makes
7015 things like for(;;) statements work better.) */
7017 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7018 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7019 ecs
->event_thread
->control
.may_range_step
= 1;
7020 set_step_info (frame
, stop_pc_sal
);
7023 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
7027 /* In all-stop mode, if we're currently stepping but have stopped in
7028 some other thread, we may need to switch back to the stepped
7029 thread. Returns true we set the inferior running, false if we left
7030 it stopped (and the event needs further processing). */
7033 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7035 if (!target_is_non_stop_p ())
7037 struct thread_info
*tp
;
7038 struct thread_info
*stepping_thread
;
7040 /* If any thread is blocked on some internal breakpoint, and we
7041 simply need to step over that breakpoint to get it going
7042 again, do that first. */
7044 /* However, if we see an event for the stepping thread, then we
7045 know all other threads have been moved past their breakpoints
7046 already. Let the caller check whether the step is finished,
7047 etc., before deciding to move it past a breakpoint. */
7048 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7051 /* Check if the current thread is blocked on an incomplete
7052 step-over, interrupted by a random signal. */
7053 if (ecs
->event_thread
->control
.trap_expected
7054 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7058 fprintf_unfiltered (gdb_stdlog
,
7059 "infrun: need to finish step-over of [%s]\n",
7060 target_pid_to_str (ecs
->event_thread
->ptid
));
7066 /* Check if the current thread is blocked by a single-step
7067 breakpoint of another thread. */
7068 if (ecs
->hit_singlestep_breakpoint
)
7072 fprintf_unfiltered (gdb_stdlog
,
7073 "infrun: need to step [%s] over single-step "
7075 target_pid_to_str (ecs
->ptid
));
7081 /* If this thread needs yet another step-over (e.g., stepping
7082 through a delay slot), do it first before moving on to
7084 if (thread_still_needs_step_over (ecs
->event_thread
))
7088 fprintf_unfiltered (gdb_stdlog
,
7089 "infrun: thread [%s] still needs step-over\n",
7090 target_pid_to_str (ecs
->event_thread
->ptid
));
7096 /* If scheduler locking applies even if not stepping, there's no
7097 need to walk over threads. Above we've checked whether the
7098 current thread is stepping. If some other thread not the
7099 event thread is stepping, then it must be that scheduler
7100 locking is not in effect. */
7101 if (schedlock_applies (ecs
->event_thread
))
7104 /* Otherwise, we no longer expect a trap in the current thread.
7105 Clear the trap_expected flag before switching back -- this is
7106 what keep_going does as well, if we call it. */
7107 ecs
->event_thread
->control
.trap_expected
= 0;
7109 /* Likewise, clear the signal if it should not be passed. */
7110 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7111 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7113 /* Do all pending step-overs before actually proceeding with
7115 if (start_step_over ())
7117 prepare_to_wait (ecs
);
7121 /* Look for the stepping/nexting thread. */
7122 stepping_thread
= NULL
;
7124 ALL_NON_EXITED_THREADS (tp
)
7126 /* Ignore threads of processes the caller is not
7129 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
7132 /* When stepping over a breakpoint, we lock all threads
7133 except the one that needs to move past the breakpoint.
7134 If a non-event thread has this set, the "incomplete
7135 step-over" check above should have caught it earlier. */
7136 if (tp
->control
.trap_expected
)
7138 internal_error (__FILE__
, __LINE__
,
7139 "[%s] has inconsistent state: "
7140 "trap_expected=%d\n",
7141 target_pid_to_str (tp
->ptid
),
7142 tp
->control
.trap_expected
);
7145 /* Did we find the stepping thread? */
7146 if (tp
->control
.step_range_end
)
7148 /* Yep. There should only one though. */
7149 gdb_assert (stepping_thread
== NULL
);
7151 /* The event thread is handled at the top, before we
7153 gdb_assert (tp
!= ecs
->event_thread
);
7155 /* If some thread other than the event thread is
7156 stepping, then scheduler locking can't be in effect,
7157 otherwise we wouldn't have resumed the current event
7158 thread in the first place. */
7159 gdb_assert (!schedlock_applies (tp
));
7161 stepping_thread
= tp
;
7165 if (stepping_thread
!= NULL
)
7168 fprintf_unfiltered (gdb_stdlog
,
7169 "infrun: switching back to stepped thread\n");
7171 if (keep_going_stepped_thread (stepping_thread
))
7173 prepare_to_wait (ecs
);
7182 /* Set a previously stepped thread back to stepping. Returns true on
7183 success, false if the resume is not possible (e.g., the thread
7187 keep_going_stepped_thread (struct thread_info
*tp
)
7189 struct frame_info
*frame
;
7190 struct execution_control_state ecss
;
7191 struct execution_control_state
*ecs
= &ecss
;
7193 /* If the stepping thread exited, then don't try to switch back and
7194 resume it, which could fail in several different ways depending
7195 on the target. Instead, just keep going.
7197 We can find a stepping dead thread in the thread list in two
7200 - The target supports thread exit events, and when the target
7201 tries to delete the thread from the thread list, inferior_ptid
7202 pointed at the exiting thread. In such case, calling
7203 delete_thread does not really remove the thread from the list;
7204 instead, the thread is left listed, with 'exited' state.
7206 - The target's debug interface does not support thread exit
7207 events, and so we have no idea whatsoever if the previously
7208 stepping thread is still alive. For that reason, we need to
7209 synchronously query the target now. */
7211 if (is_exited (tp
->ptid
)
7212 || !target_thread_alive (tp
->ptid
))
7215 fprintf_unfiltered (gdb_stdlog
,
7216 "infrun: not resuming previously "
7217 "stepped thread, it has vanished\n");
7219 delete_thread (tp
->ptid
);
7224 fprintf_unfiltered (gdb_stdlog
,
7225 "infrun: resuming previously stepped thread\n");
7227 reset_ecs (ecs
, tp
);
7228 switch_to_thread (tp
->ptid
);
7230 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7231 frame
= get_current_frame ();
7233 /* If the PC of the thread we were trying to single-step has
7234 changed, then that thread has trapped or been signaled, but the
7235 event has not been reported to GDB yet. Re-poll the target
7236 looking for this particular thread's event (i.e. temporarily
7237 enable schedlock) by:
7239 - setting a break at the current PC
7240 - resuming that particular thread, only (by setting trap
7243 This prevents us continuously moving the single-step breakpoint
7244 forward, one instruction at a time, overstepping. */
7246 if (stop_pc
!= tp
->prev_pc
)
7251 fprintf_unfiltered (gdb_stdlog
,
7252 "infrun: expected thread advanced also (%s -> %s)\n",
7253 paddress (target_gdbarch (), tp
->prev_pc
),
7254 paddress (target_gdbarch (), stop_pc
));
7256 /* Clear the info of the previous step-over, as it's no longer
7257 valid (if the thread was trying to step over a breakpoint, it
7258 has already succeeded). It's what keep_going would do too,
7259 if we called it. Do this before trying to insert the sss
7260 breakpoint, otherwise if we were previously trying to step
7261 over this exact address in another thread, the breakpoint is
7263 clear_step_over_info ();
7264 tp
->control
.trap_expected
= 0;
7266 insert_single_step_breakpoint (get_frame_arch (frame
),
7267 get_frame_address_space (frame
),
7271 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7272 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7277 fprintf_unfiltered (gdb_stdlog
,
7278 "infrun: expected thread still hasn't advanced\n");
7280 keep_going_pass_signal (ecs
);
7285 /* Is thread TP in the middle of (software or hardware)
7286 single-stepping? (Note the result of this function must never be
7287 passed directly as target_resume's STEP parameter.) */
7290 currently_stepping (struct thread_info
*tp
)
7292 return ((tp
->control
.step_range_end
7293 && tp
->control
.step_resume_breakpoint
== NULL
)
7294 || tp
->control
.trap_expected
7295 || tp
->stepped_breakpoint
7296 || bpstat_should_step ());
7299 /* Inferior has stepped into a subroutine call with source code that
7300 we should not step over. Do step to the first line of code in
7304 handle_step_into_function (struct gdbarch
*gdbarch
,
7305 struct execution_control_state
*ecs
)
7307 struct compunit_symtab
*cust
;
7308 struct symtab_and_line stop_func_sal
, sr_sal
;
7310 fill_in_stop_func (gdbarch
, ecs
);
7312 cust
= find_pc_compunit_symtab (stop_pc
);
7313 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7314 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7315 ecs
->stop_func_start
);
7317 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7318 /* Use the step_resume_break to step until the end of the prologue,
7319 even if that involves jumps (as it seems to on the vax under
7321 /* If the prologue ends in the middle of a source line, continue to
7322 the end of that source line (if it is still within the function).
7323 Otherwise, just go to end of prologue. */
7324 if (stop_func_sal
.end
7325 && stop_func_sal
.pc
!= ecs
->stop_func_start
7326 && stop_func_sal
.end
< ecs
->stop_func_end
)
7327 ecs
->stop_func_start
= stop_func_sal
.end
;
7329 /* Architectures which require breakpoint adjustment might not be able
7330 to place a breakpoint at the computed address. If so, the test
7331 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7332 ecs->stop_func_start to an address at which a breakpoint may be
7333 legitimately placed.
7335 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7336 made, GDB will enter an infinite loop when stepping through
7337 optimized code consisting of VLIW instructions which contain
7338 subinstructions corresponding to different source lines. On
7339 FR-V, it's not permitted to place a breakpoint on any but the
7340 first subinstruction of a VLIW instruction. When a breakpoint is
7341 set, GDB will adjust the breakpoint address to the beginning of
7342 the VLIW instruction. Thus, we need to make the corresponding
7343 adjustment here when computing the stop address. */
7345 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7347 ecs
->stop_func_start
7348 = gdbarch_adjust_breakpoint_address (gdbarch
,
7349 ecs
->stop_func_start
);
7352 if (ecs
->stop_func_start
== stop_pc
)
7354 /* We are already there: stop now. */
7355 end_stepping_range (ecs
);
7360 /* Put the step-breakpoint there and go until there. */
7361 init_sal (&sr_sal
); /* initialize to zeroes */
7362 sr_sal
.pc
= ecs
->stop_func_start
;
7363 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7364 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7366 /* Do not specify what the fp should be when we stop since on
7367 some machines the prologue is where the new fp value is
7369 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7371 /* And make sure stepping stops right away then. */
7372 ecs
->event_thread
->control
.step_range_end
7373 = ecs
->event_thread
->control
.step_range_start
;
7378 /* Inferior has stepped backward into a subroutine call with source
7379 code that we should not step over. Do step to the beginning of the
7380 last line of code in it. */
7383 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7384 struct execution_control_state
*ecs
)
7386 struct compunit_symtab
*cust
;
7387 struct symtab_and_line stop_func_sal
;
7389 fill_in_stop_func (gdbarch
, ecs
);
7391 cust
= find_pc_compunit_symtab (stop_pc
);
7392 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7393 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7394 ecs
->stop_func_start
);
7396 stop_func_sal
= find_pc_line (stop_pc
, 0);
7398 /* OK, we're just going to keep stepping here. */
7399 if (stop_func_sal
.pc
== stop_pc
)
7401 /* We're there already. Just stop stepping now. */
7402 end_stepping_range (ecs
);
7406 /* Else just reset the step range and keep going.
7407 No step-resume breakpoint, they don't work for
7408 epilogues, which can have multiple entry paths. */
7409 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7410 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7416 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7417 This is used to both functions and to skip over code. */
7420 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7421 struct symtab_and_line sr_sal
,
7422 struct frame_id sr_id
,
7423 enum bptype sr_type
)
7425 /* There should never be more than one step-resume or longjmp-resume
7426 breakpoint per thread, so we should never be setting a new
7427 step_resume_breakpoint when one is already active. */
7428 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7429 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7432 fprintf_unfiltered (gdb_stdlog
,
7433 "infrun: inserting step-resume breakpoint at %s\n",
7434 paddress (gdbarch
, sr_sal
.pc
));
7436 inferior_thread ()->control
.step_resume_breakpoint
7437 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7441 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7442 struct symtab_and_line sr_sal
,
7443 struct frame_id sr_id
)
7445 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7450 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7451 This is used to skip a potential signal handler.
7453 This is called with the interrupted function's frame. The signal
7454 handler, when it returns, will resume the interrupted function at
7458 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7460 struct symtab_and_line sr_sal
;
7461 struct gdbarch
*gdbarch
;
7463 gdb_assert (return_frame
!= NULL
);
7464 init_sal (&sr_sal
); /* initialize to zeros */
7466 gdbarch
= get_frame_arch (return_frame
);
7467 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7468 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7469 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7471 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7472 get_stack_frame_id (return_frame
),
7476 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7477 is used to skip a function after stepping into it (for "next" or if
7478 the called function has no debugging information).
7480 The current function has almost always been reached by single
7481 stepping a call or return instruction. NEXT_FRAME belongs to the
7482 current function, and the breakpoint will be set at the caller's
7485 This is a separate function rather than reusing
7486 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7487 get_prev_frame, which may stop prematurely (see the implementation
7488 of frame_unwind_caller_id for an example). */
7491 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7493 struct symtab_and_line sr_sal
;
7494 struct gdbarch
*gdbarch
;
7496 /* We shouldn't have gotten here if we don't know where the call site
7498 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7500 init_sal (&sr_sal
); /* initialize to zeros */
7502 gdbarch
= frame_unwind_caller_arch (next_frame
);
7503 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7504 frame_unwind_caller_pc (next_frame
));
7505 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7506 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7508 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7509 frame_unwind_caller_id (next_frame
));
7512 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7513 new breakpoint at the target of a jmp_buf. The handling of
7514 longjmp-resume uses the same mechanisms used for handling
7515 "step-resume" breakpoints. */
7518 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7520 /* There should never be more than one longjmp-resume breakpoint per
7521 thread, so we should never be setting a new
7522 longjmp_resume_breakpoint when one is already active. */
7523 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7526 fprintf_unfiltered (gdb_stdlog
,
7527 "infrun: inserting longjmp-resume breakpoint at %s\n",
7528 paddress (gdbarch
, pc
));
7530 inferior_thread ()->control
.exception_resume_breakpoint
=
7531 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7534 /* Insert an exception resume breakpoint. TP is the thread throwing
7535 the exception. The block B is the block of the unwinder debug hook
7536 function. FRAME is the frame corresponding to the call to this
7537 function. SYM is the symbol of the function argument holding the
7538 target PC of the exception. */
7541 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7542 const struct block
*b
,
7543 struct frame_info
*frame
,
7548 struct block_symbol vsym
;
7549 struct value
*value
;
7551 struct breakpoint
*bp
;
7553 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
7554 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7555 /* If the value was optimized out, revert to the old behavior. */
7556 if (! value_optimized_out (value
))
7558 handler
= value_as_address (value
);
7561 fprintf_unfiltered (gdb_stdlog
,
7562 "infrun: exception resume at %lx\n",
7563 (unsigned long) handler
);
7565 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7566 handler
, bp_exception_resume
);
7568 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7571 bp
->thread
= tp
->global_num
;
7572 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7575 CATCH (e
, RETURN_MASK_ERROR
)
7577 /* We want to ignore errors here. */
7582 /* A helper for check_exception_resume that sets an
7583 exception-breakpoint based on a SystemTap probe. */
7586 insert_exception_resume_from_probe (struct thread_info
*tp
,
7587 const struct bound_probe
*probe
,
7588 struct frame_info
*frame
)
7590 struct value
*arg_value
;
7592 struct breakpoint
*bp
;
7594 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7598 handler
= value_as_address (arg_value
);
7601 fprintf_unfiltered (gdb_stdlog
,
7602 "infrun: exception resume at %s\n",
7603 paddress (get_objfile_arch (probe
->objfile
),
7606 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7607 handler
, bp_exception_resume
);
7608 bp
->thread
= tp
->global_num
;
7609 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7612 /* This is called when an exception has been intercepted. Check to
7613 see whether the exception's destination is of interest, and if so,
7614 set an exception resume breakpoint there. */
7617 check_exception_resume (struct execution_control_state
*ecs
,
7618 struct frame_info
*frame
)
7620 struct bound_probe probe
;
7621 struct symbol
*func
;
7623 /* First see if this exception unwinding breakpoint was set via a
7624 SystemTap probe point. If so, the probe has two arguments: the
7625 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7626 set a breakpoint there. */
7627 probe
= find_probe_by_pc (get_frame_pc (frame
));
7630 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7634 func
= get_frame_function (frame
);
7640 const struct block
*b
;
7641 struct block_iterator iter
;
7645 /* The exception breakpoint is a thread-specific breakpoint on
7646 the unwinder's debug hook, declared as:
7648 void _Unwind_DebugHook (void *cfa, void *handler);
7650 The CFA argument indicates the frame to which control is
7651 about to be transferred. HANDLER is the destination PC.
7653 We ignore the CFA and set a temporary breakpoint at HANDLER.
7654 This is not extremely efficient but it avoids issues in gdb
7655 with computing the DWARF CFA, and it also works even in weird
7656 cases such as throwing an exception from inside a signal
7659 b
= SYMBOL_BLOCK_VALUE (func
);
7660 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7662 if (!SYMBOL_IS_ARGUMENT (sym
))
7669 insert_exception_resume_breakpoint (ecs
->event_thread
,
7675 CATCH (e
, RETURN_MASK_ERROR
)
7682 stop_waiting (struct execution_control_state
*ecs
)
7685 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7687 clear_step_over_info ();
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 (ui_out_is_mi_like_p (uiout
))
7896 ui_out_field_string (uiout
, "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 (ui_out_is_mi_like_p (uiout
))
7907 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7908 ui_out_text (uiout
, "\nProgram terminated with signal ");
7909 annotate_signal_name ();
7910 ui_out_field_string (uiout
, "signal-name",
7911 gdb_signal_to_name (siggnal
));
7912 annotate_signal_name_end ();
7913 ui_out_text (uiout
, ", ");
7914 annotate_signal_string ();
7915 ui_out_field_string (uiout
, "signal-meaning",
7916 gdb_signal_to_string (siggnal
));
7917 annotate_signal_string_end ();
7918 ui_out_text (uiout
, ".\n");
7919 ui_out_text (uiout
, "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 (ui_out_is_mi_like_p (uiout
))
7932 ui_out_field_string (uiout
, "reason",
7933 async_reason_lookup (EXEC_ASYNC_EXITED
));
7934 ui_out_text (uiout
, "[Inferior ");
7935 ui_out_text (uiout
, plongest (inf
->num
));
7936 ui_out_text (uiout
, " (");
7937 ui_out_text (uiout
, pidstr
);
7938 ui_out_text (uiout
, ") exited with code ");
7939 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
7940 ui_out_text (uiout
, "]\n");
7944 if (ui_out_is_mi_like_p (uiout
))
7946 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7947 ui_out_text (uiout
, "[Inferior ");
7948 ui_out_text (uiout
, plongest (inf
->num
));
7949 ui_out_text (uiout
, " (");
7950 ui_out_text (uiout
, pidstr
);
7951 ui_out_text (uiout
, ") exited normally]\n");
7955 /* Some targets/architectures can do extra processing/display of
7956 segmentation faults. E.g., Intel MPX boundary faults.
7957 Call the architecture dependent function to handle the fault. */
7960 handle_segmentation_fault (struct ui_out
*uiout
)
7962 struct regcache
*regcache
= get_current_regcache ();
7963 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7965 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7966 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7970 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7972 struct thread_info
*thr
= inferior_thread ();
7976 if (ui_out_is_mi_like_p (uiout
))
7978 else if (show_thread_that_caused_stop ())
7982 ui_out_text (uiout
, "\nThread ");
7983 ui_out_field_fmt (uiout
, "thread-id", "%s", print_thread_id (thr
));
7985 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7988 ui_out_text (uiout
, " \"");
7989 ui_out_field_fmt (uiout
, "name", "%s", name
);
7990 ui_out_text (uiout
, "\"");
7994 ui_out_text (uiout
, "\nProgram");
7996 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
7997 ui_out_text (uiout
, " stopped");
8000 ui_out_text (uiout
, " received signal ");
8001 annotate_signal_name ();
8002 if (ui_out_is_mi_like_p (uiout
))
8004 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
8005 ui_out_field_string (uiout
, "signal-name",
8006 gdb_signal_to_name (siggnal
));
8007 annotate_signal_name_end ();
8008 ui_out_text (uiout
, ", ");
8009 annotate_signal_string ();
8010 ui_out_field_string (uiout
, "signal-meaning",
8011 gdb_signal_to_string (siggnal
));
8013 if (siggnal
== GDB_SIGNAL_SEGV
)
8014 handle_segmentation_fault (uiout
);
8016 annotate_signal_string_end ();
8018 ui_out_text (uiout
, ".\n");
8022 print_no_history_reason (struct ui_out
*uiout
)
8024 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
8027 /* Print current location without a level number, if we have changed
8028 functions or hit a breakpoint. Print source line if we have one.
8029 bpstat_print contains the logic deciding in detail what to print,
8030 based on the event(s) that just occurred. */
8033 print_stop_location (struct target_waitstatus
*ws
)
8036 enum print_what source_flag
;
8037 int do_frame_printing
= 1;
8038 struct thread_info
*tp
= inferior_thread ();
8040 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8044 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8045 should) carry around the function and does (or should) use
8046 that when doing a frame comparison. */
8047 if (tp
->control
.stop_step
8048 && frame_id_eq (tp
->control
.step_frame_id
,
8049 get_frame_id (get_current_frame ()))
8050 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
8052 /* Finished step, just print source line. */
8053 source_flag
= SRC_LINE
;
8057 /* Print location and source line. */
8058 source_flag
= SRC_AND_LOC
;
8061 case PRINT_SRC_AND_LOC
:
8062 /* Print location and source line. */
8063 source_flag
= SRC_AND_LOC
;
8065 case PRINT_SRC_ONLY
:
8066 source_flag
= SRC_LINE
;
8069 /* Something bogus. */
8070 source_flag
= SRC_LINE
;
8071 do_frame_printing
= 0;
8074 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8077 /* The behavior of this routine with respect to the source
8079 SRC_LINE: Print only source line
8080 LOCATION: Print only location
8081 SRC_AND_LOC: Print location and source line. */
8082 if (do_frame_printing
)
8083 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8089 print_stop_event (struct ui_out
*uiout
)
8091 struct target_waitstatus last
;
8093 struct thread_info
*tp
;
8095 get_last_target_status (&last_ptid
, &last
);
8098 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8100 print_stop_location (&last
);
8102 /* Display the auto-display expressions. */
8106 tp
= inferior_thread ();
8107 if (tp
->thread_fsm
!= NULL
8108 && thread_fsm_finished_p (tp
->thread_fsm
))
8110 struct return_value_info
*rv
;
8112 rv
= thread_fsm_return_value (tp
->thread_fsm
);
8114 print_return_value (uiout
, rv
);
8121 maybe_remove_breakpoints (void)
8123 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
8125 if (remove_breakpoints ())
8127 target_terminal_ours_for_output ();
8128 printf_filtered (_("Cannot remove breakpoints because "
8129 "program is no longer writable.\nFurther "
8130 "execution is probably impossible.\n"));
8135 /* The execution context that just caused a normal stop. */
8142 /* The event PTID. */
8146 /* If stopp for a thread event, this is the thread that caused the
8148 struct thread_info
*thread
;
8150 /* The inferior that caused the stop. */
8154 /* Returns a new stop context. If stopped for a thread event, this
8155 takes a strong reference to the thread. */
8157 static struct stop_context
*
8158 save_stop_context (void)
8160 struct stop_context
*sc
= XNEW (struct stop_context
);
8162 sc
->stop_id
= get_stop_id ();
8163 sc
->ptid
= inferior_ptid
;
8164 sc
->inf_num
= current_inferior ()->num
;
8166 if (!ptid_equal (inferior_ptid
, null_ptid
))
8168 /* Take a strong reference so that the thread can't be deleted
8170 sc
->thread
= inferior_thread ();
8171 sc
->thread
->refcount
++;
8179 /* Release a stop context previously created with save_stop_context.
8180 Releases the strong reference to the thread as well. */
8183 release_stop_context_cleanup (void *arg
)
8185 struct stop_context
*sc
= (struct stop_context
*) arg
;
8187 if (sc
->thread
!= NULL
)
8188 sc
->thread
->refcount
--;
8192 /* Return true if the current context no longer matches the saved stop
8196 stop_context_changed (struct stop_context
*prev
)
8198 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
8200 if (prev
->inf_num
!= current_inferior ()->num
)
8202 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
8204 if (get_stop_id () != prev
->stop_id
)
8214 struct target_waitstatus last
;
8216 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
8219 get_last_target_status (&last_ptid
, &last
);
8223 /* If an exception is thrown from this point on, make sure to
8224 propagate GDB's knowledge of the executing state to the
8225 frontend/user running state. A QUIT is an easy exception to see
8226 here, so do this before any filtered output. */
8228 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
8229 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8230 || last
.kind
== TARGET_WAITKIND_EXITED
)
8232 /* On some targets, we may still have live threads in the
8233 inferior when we get a process exit event. E.g., for
8234 "checkpoint", when the current checkpoint/fork exits,
8235 linux-fork.c automatically switches to another fork from
8236 within target_mourn_inferior. */
8237 if (!ptid_equal (inferior_ptid
, null_ptid
))
8239 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8240 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8243 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8244 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8246 /* As we're presenting a stop, and potentially removing breakpoints,
8247 update the thread list so we can tell whether there are threads
8248 running on the target. With target remote, for example, we can
8249 only learn about new threads when we explicitly update the thread
8250 list. Do this before notifying the interpreters about signal
8251 stops, end of stepping ranges, etc., so that the "new thread"
8252 output is emitted before e.g., "Program received signal FOO",
8253 instead of after. */
8254 update_thread_list ();
8256 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8257 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
8259 /* As with the notification of thread events, we want to delay
8260 notifying the user that we've switched thread context until
8261 the inferior actually stops.
8263 There's no point in saying anything if the inferior has exited.
8264 Note that SIGNALLED here means "exited with a signal", not
8265 "received a signal".
8267 Also skip saying anything in non-stop mode. In that mode, as we
8268 don't want GDB to switch threads behind the user's back, to avoid
8269 races where the user is typing a command to apply to thread x,
8270 but GDB switches to thread y before the user finishes entering
8271 the command, fetch_inferior_event installs a cleanup to restore
8272 the current thread back to the thread the user had selected right
8273 after this event is handled, so we're not really switching, only
8274 informing of a stop. */
8276 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8277 && target_has_execution
8278 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8279 && last
.kind
!= TARGET_WAITKIND_EXITED
8280 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8282 SWITCH_THRU_ALL_UIS ()
8284 target_terminal_ours_for_output ();
8285 printf_filtered (_("[Switching to %s]\n"),
8286 target_pid_to_str (inferior_ptid
));
8287 annotate_thread_changed ();
8289 previous_inferior_ptid
= inferior_ptid
;
8292 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8294 SWITCH_THRU_ALL_UIS ()
8295 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8297 target_terminal_ours_for_output ();
8298 printf_filtered (_("No unwaited-for children left.\n"));
8302 /* Note: this depends on the update_thread_list call above. */
8303 maybe_remove_breakpoints ();
8305 /* If an auto-display called a function and that got a signal,
8306 delete that auto-display to avoid an infinite recursion. */
8308 if (stopped_by_random_signal
)
8309 disable_current_display ();
8311 SWITCH_THRU_ALL_UIS ()
8313 async_enable_stdin ();
8316 /* Let the user/frontend see the threads as stopped. */
8317 do_cleanups (old_chain
);
8319 /* Select innermost stack frame - i.e., current frame is frame 0,
8320 and current location is based on that. Handle the case where the
8321 dummy call is returning after being stopped. E.g. the dummy call
8322 previously hit a breakpoint. (If the dummy call returns
8323 normally, we won't reach here.) Do this before the stop hook is
8324 run, so that it doesn't get to see the temporary dummy frame,
8325 which is not where we'll present the stop. */
8326 if (has_stack_frames ())
8328 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8330 /* Pop the empty frame that contains the stack dummy. This
8331 also restores inferior state prior to the call (struct
8332 infcall_suspend_state). */
8333 struct frame_info
*frame
= get_current_frame ();
8335 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8337 /* frame_pop calls reinit_frame_cache as the last thing it
8338 does which means there's now no selected frame. */
8341 select_frame (get_current_frame ());
8343 /* Set the current source location. */
8344 set_current_sal_from_frame (get_current_frame ());
8347 /* Look up the hook_stop and run it (CLI internally handles problem
8348 of stop_command's pre-hook not existing). */
8349 if (stop_command
!= NULL
)
8351 struct stop_context
*saved_context
= save_stop_context ();
8352 struct cleanup
*old_chain
8353 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8355 catch_errors (hook_stop_stub
, stop_command
,
8356 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
8358 /* If the stop hook resumes the target, then there's no point in
8359 trying to notify about the previous stop; its context is
8360 gone. Likewise if the command switches thread or inferior --
8361 the observers would print a stop for the wrong
8363 if (stop_context_changed (saved_context
))
8365 do_cleanups (old_chain
);
8368 do_cleanups (old_chain
);
8371 /* Notify observers about the stop. This is where the interpreters
8372 print the stop event. */
8373 if (!ptid_equal (inferior_ptid
, null_ptid
))
8374 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
8377 observer_notify_normal_stop (NULL
, stop_print_frame
);
8379 annotate_stopped ();
8381 if (target_has_execution
)
8383 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8384 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8385 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8386 Delete any breakpoint that is to be deleted at the next stop. */
8387 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8390 /* Try to get rid of automatically added inferiors that are no
8391 longer needed. Keeping those around slows down things linearly.
8392 Note that this never removes the current inferior. */
8399 hook_stop_stub (void *cmd
)
8401 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
8406 signal_stop_state (int signo
)
8408 return signal_stop
[signo
];
8412 signal_print_state (int signo
)
8414 return signal_print
[signo
];
8418 signal_pass_state (int signo
)
8420 return signal_program
[signo
];
8424 signal_cache_update (int signo
)
8428 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8429 signal_cache_update (signo
);
8434 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8435 && signal_print
[signo
] == 0
8436 && signal_program
[signo
] == 1
8437 && signal_catch
[signo
] == 0);
8441 signal_stop_update (int signo
, int state
)
8443 int ret
= signal_stop
[signo
];
8445 signal_stop
[signo
] = state
;
8446 signal_cache_update (signo
);
8451 signal_print_update (int signo
, int state
)
8453 int ret
= signal_print
[signo
];
8455 signal_print
[signo
] = state
;
8456 signal_cache_update (signo
);
8461 signal_pass_update (int signo
, int state
)
8463 int ret
= signal_program
[signo
];
8465 signal_program
[signo
] = state
;
8466 signal_cache_update (signo
);
8470 /* Update the global 'signal_catch' from INFO and notify the
8474 signal_catch_update (const unsigned int *info
)
8478 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8479 signal_catch
[i
] = info
[i
] > 0;
8480 signal_cache_update (-1);
8481 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8485 sig_print_header (void)
8487 printf_filtered (_("Signal Stop\tPrint\tPass "
8488 "to program\tDescription\n"));
8492 sig_print_info (enum gdb_signal oursig
)
8494 const char *name
= gdb_signal_to_name (oursig
);
8495 int name_padding
= 13 - strlen (name
);
8497 if (name_padding
<= 0)
8500 printf_filtered ("%s", name
);
8501 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8502 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8503 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8504 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8505 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8508 /* Specify how various signals in the inferior should be handled. */
8511 handle_command (char *args
, int from_tty
)
8514 int digits
, wordlen
;
8515 int sigfirst
, signum
, siglast
;
8516 enum gdb_signal oursig
;
8519 unsigned char *sigs
;
8520 struct cleanup
*old_chain
;
8524 error_no_arg (_("signal to handle"));
8527 /* Allocate and zero an array of flags for which signals to handle. */
8529 nsigs
= (int) GDB_SIGNAL_LAST
;
8530 sigs
= (unsigned char *) alloca (nsigs
);
8531 memset (sigs
, 0, nsigs
);
8533 /* Break the command line up into args. */
8535 argv
= gdb_buildargv (args
);
8536 old_chain
= make_cleanup_freeargv (argv
);
8538 /* Walk through the args, looking for signal oursigs, signal names, and
8539 actions. Signal numbers and signal names may be interspersed with
8540 actions, with the actions being performed for all signals cumulatively
8541 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8543 while (*argv
!= NULL
)
8545 wordlen
= strlen (*argv
);
8546 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
8550 sigfirst
= siglast
= -1;
8552 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
8554 /* Apply action to all signals except those used by the
8555 debugger. Silently skip those. */
8558 siglast
= nsigs
- 1;
8560 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
8562 SET_SIGS (nsigs
, sigs
, signal_stop
);
8563 SET_SIGS (nsigs
, sigs
, signal_print
);
8565 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
8567 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8569 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
8571 SET_SIGS (nsigs
, sigs
, signal_print
);
8573 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
8575 SET_SIGS (nsigs
, sigs
, signal_program
);
8577 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
8579 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8581 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
8583 SET_SIGS (nsigs
, sigs
, signal_program
);
8585 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
8587 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8588 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8590 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
8592 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8594 else if (digits
> 0)
8596 /* It is numeric. The numeric signal refers to our own
8597 internal signal numbering from target.h, not to host/target
8598 signal number. This is a feature; users really should be
8599 using symbolic names anyway, and the common ones like
8600 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8602 sigfirst
= siglast
= (int)
8603 gdb_signal_from_command (atoi (*argv
));
8604 if ((*argv
)[digits
] == '-')
8607 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
8609 if (sigfirst
> siglast
)
8611 /* Bet he didn't figure we'd think of this case... */
8619 oursig
= gdb_signal_from_name (*argv
);
8620 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8622 sigfirst
= siglast
= (int) oursig
;
8626 /* Not a number and not a recognized flag word => complain. */
8627 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
8631 /* If any signal numbers or symbol names were found, set flags for
8632 which signals to apply actions to. */
8634 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8636 switch ((enum gdb_signal
) signum
)
8638 case GDB_SIGNAL_TRAP
:
8639 case GDB_SIGNAL_INT
:
8640 if (!allsigs
&& !sigs
[signum
])
8642 if (query (_("%s is used by the debugger.\n\
8643 Are you sure you want to change it? "),
8644 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8650 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8651 gdb_flush (gdb_stdout
);
8656 case GDB_SIGNAL_DEFAULT
:
8657 case GDB_SIGNAL_UNKNOWN
:
8658 /* Make sure that "all" doesn't print these. */
8669 for (signum
= 0; signum
< nsigs
; signum
++)
8672 signal_cache_update (-1);
8673 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8674 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8678 /* Show the results. */
8679 sig_print_header ();
8680 for (; signum
< nsigs
; signum
++)
8682 sig_print_info ((enum gdb_signal
) signum
);
8688 do_cleanups (old_chain
);
8691 /* Complete the "handle" command. */
8693 static VEC (char_ptr
) *
8694 handle_completer (struct cmd_list_element
*ignore
,
8695 const char *text
, const char *word
)
8697 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
8698 static const char * const keywords
[] =
8712 vec_signals
= signal_completer (ignore
, text
, word
);
8713 vec_keywords
= complete_on_enum (keywords
, word
, word
);
8715 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
8716 VEC_free (char_ptr
, vec_signals
);
8717 VEC_free (char_ptr
, vec_keywords
);
8722 gdb_signal_from_command (int num
)
8724 if (num
>= 1 && num
<= 15)
8725 return (enum gdb_signal
) num
;
8726 error (_("Only signals 1-15 are valid as numeric signals.\n\
8727 Use \"info signals\" for a list of symbolic signals."));
8730 /* Print current contents of the tables set by the handle command.
8731 It is possible we should just be printing signals actually used
8732 by the current target (but for things to work right when switching
8733 targets, all signals should be in the signal tables). */
8736 signals_info (char *signum_exp
, int from_tty
)
8738 enum gdb_signal oursig
;
8740 sig_print_header ();
8744 /* First see if this is a symbol name. */
8745 oursig
= gdb_signal_from_name (signum_exp
);
8746 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8748 /* No, try numeric. */
8750 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8752 sig_print_info (oursig
);
8756 printf_filtered ("\n");
8757 /* These ugly casts brought to you by the native VAX compiler. */
8758 for (oursig
= GDB_SIGNAL_FIRST
;
8759 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8760 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8764 if (oursig
!= GDB_SIGNAL_UNKNOWN
8765 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8766 sig_print_info (oursig
);
8769 printf_filtered (_("\nUse the \"handle\" command "
8770 "to change these tables.\n"));
8773 /* The $_siginfo convenience variable is a bit special. We don't know
8774 for sure the type of the value until we actually have a chance to
8775 fetch the data. The type can change depending on gdbarch, so it is
8776 also dependent on which thread you have selected.
8778 1. making $_siginfo be an internalvar that creates a new value on
8781 2. making the value of $_siginfo be an lval_computed value. */
8783 /* This function implements the lval_computed support for reading a
8787 siginfo_value_read (struct value
*v
)
8789 LONGEST transferred
;
8791 /* If we can access registers, so can we access $_siginfo. Likewise
8793 validate_registers_access ();
8796 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8798 value_contents_all_raw (v
),
8800 TYPE_LENGTH (value_type (v
)));
8802 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8803 error (_("Unable to read siginfo"));
8806 /* This function implements the lval_computed support for writing a
8810 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8812 LONGEST transferred
;
8814 /* If we can access registers, so can we access $_siginfo. Likewise
8816 validate_registers_access ();
8818 transferred
= target_write (¤t_target
,
8819 TARGET_OBJECT_SIGNAL_INFO
,
8821 value_contents_all_raw (fromval
),
8823 TYPE_LENGTH (value_type (fromval
)));
8825 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8826 error (_("Unable to write siginfo"));
8829 static const struct lval_funcs siginfo_value_funcs
=
8835 /* Return a new value with the correct type for the siginfo object of
8836 the current thread using architecture GDBARCH. Return a void value
8837 if there's no object available. */
8839 static struct value
*
8840 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8843 if (target_has_stack
8844 && !ptid_equal (inferior_ptid
, null_ptid
)
8845 && gdbarch_get_siginfo_type_p (gdbarch
))
8847 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8849 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8852 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8856 /* infcall_suspend_state contains state about the program itself like its
8857 registers and any signal it received when it last stopped.
8858 This state must be restored regardless of how the inferior function call
8859 ends (either successfully, or after it hits a breakpoint or signal)
8860 if the program is to properly continue where it left off. */
8862 struct infcall_suspend_state
8864 struct thread_suspend_state thread_suspend
;
8868 struct regcache
*registers
;
8870 /* Format of SIGINFO_DATA or NULL if it is not present. */
8871 struct gdbarch
*siginfo_gdbarch
;
8873 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8874 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8875 content would be invalid. */
8876 gdb_byte
*siginfo_data
;
8879 struct infcall_suspend_state
*
8880 save_infcall_suspend_state (void)
8882 struct infcall_suspend_state
*inf_state
;
8883 struct thread_info
*tp
= inferior_thread ();
8884 struct regcache
*regcache
= get_current_regcache ();
8885 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8886 gdb_byte
*siginfo_data
= NULL
;
8888 if (gdbarch_get_siginfo_type_p (gdbarch
))
8890 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8891 size_t len
= TYPE_LENGTH (type
);
8892 struct cleanup
*back_to
;
8894 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8895 back_to
= make_cleanup (xfree
, siginfo_data
);
8897 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8898 siginfo_data
, 0, len
) == len
)
8899 discard_cleanups (back_to
);
8902 /* Errors ignored. */
8903 do_cleanups (back_to
);
8904 siginfo_data
= NULL
;
8908 inf_state
= XCNEW (struct infcall_suspend_state
);
8912 inf_state
->siginfo_gdbarch
= gdbarch
;
8913 inf_state
->siginfo_data
= siginfo_data
;
8916 inf_state
->thread_suspend
= tp
->suspend
;
8918 /* run_inferior_call will not use the signal due to its `proceed' call with
8919 GDB_SIGNAL_0 anyway. */
8920 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8922 inf_state
->stop_pc
= stop_pc
;
8924 inf_state
->registers
= regcache_dup (regcache
);
8929 /* Restore inferior session state to INF_STATE. */
8932 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8934 struct thread_info
*tp
= inferior_thread ();
8935 struct regcache
*regcache
= get_current_regcache ();
8936 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8938 tp
->suspend
= inf_state
->thread_suspend
;
8940 stop_pc
= inf_state
->stop_pc
;
8942 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8944 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8946 /* Errors ignored. */
8947 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8948 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8951 /* The inferior can be gone if the user types "print exit(0)"
8952 (and perhaps other times). */
8953 if (target_has_execution
)
8954 /* NB: The register write goes through to the target. */
8955 regcache_cpy (regcache
, inf_state
->registers
);
8957 discard_infcall_suspend_state (inf_state
);
8961 do_restore_infcall_suspend_state_cleanup (void *state
)
8963 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
8967 make_cleanup_restore_infcall_suspend_state
8968 (struct infcall_suspend_state
*inf_state
)
8970 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8974 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8976 regcache_xfree (inf_state
->registers
);
8977 xfree (inf_state
->siginfo_data
);
8982 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8984 return inf_state
->registers
;
8987 /* infcall_control_state contains state regarding gdb's control of the
8988 inferior itself like stepping control. It also contains session state like
8989 the user's currently selected frame. */
8991 struct infcall_control_state
8993 struct thread_control_state thread_control
;
8994 struct inferior_control_state inferior_control
;
8997 enum stop_stack_kind stop_stack_dummy
;
8998 int stopped_by_random_signal
;
9000 /* ID if the selected frame when the inferior function call was made. */
9001 struct frame_id selected_frame_id
;
9004 /* Save all of the information associated with the inferior<==>gdb
9007 struct infcall_control_state
*
9008 save_infcall_control_state (void)
9010 struct infcall_control_state
*inf_status
=
9011 XNEW (struct infcall_control_state
);
9012 struct thread_info
*tp
= inferior_thread ();
9013 struct inferior
*inf
= current_inferior ();
9015 inf_status
->thread_control
= tp
->control
;
9016 inf_status
->inferior_control
= inf
->control
;
9018 tp
->control
.step_resume_breakpoint
= NULL
;
9019 tp
->control
.exception_resume_breakpoint
= NULL
;
9021 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9022 chain. If caller's caller is walking the chain, they'll be happier if we
9023 hand them back the original chain when restore_infcall_control_state is
9025 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9028 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9029 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9031 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
9037 restore_selected_frame (void *args
)
9039 struct frame_id
*fid
= (struct frame_id
*) args
;
9040 struct frame_info
*frame
;
9042 frame
= frame_find_by_id (*fid
);
9044 /* If inf_status->selected_frame_id is NULL, there was no previously
9048 warning (_("Unable to restore previously selected frame."));
9052 select_frame (frame
);
9057 /* Restore inferior session state to INF_STATUS. */
9060 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9062 struct thread_info
*tp
= inferior_thread ();
9063 struct inferior
*inf
= current_inferior ();
9065 if (tp
->control
.step_resume_breakpoint
)
9066 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9068 if (tp
->control
.exception_resume_breakpoint
)
9069 tp
->control
.exception_resume_breakpoint
->disposition
9070 = disp_del_at_next_stop
;
9072 /* Handle the bpstat_copy of the chain. */
9073 bpstat_clear (&tp
->control
.stop_bpstat
);
9075 tp
->control
= inf_status
->thread_control
;
9076 inf
->control
= inf_status
->inferior_control
;
9079 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9080 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9082 if (target_has_stack
)
9084 /* The point of catch_errors is that if the stack is clobbered,
9085 walking the stack might encounter a garbage pointer and
9086 error() trying to dereference it. */
9088 (restore_selected_frame
, &inf_status
->selected_frame_id
,
9089 "Unable to restore previously selected frame:\n",
9090 RETURN_MASK_ERROR
) == 0)
9091 /* Error in restoring the selected frame. Select the innermost
9093 select_frame (get_current_frame ());
9100 do_restore_infcall_control_state_cleanup (void *sts
)
9102 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
9106 make_cleanup_restore_infcall_control_state
9107 (struct infcall_control_state
*inf_status
)
9109 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
9113 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9115 if (inf_status
->thread_control
.step_resume_breakpoint
)
9116 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9117 = disp_del_at_next_stop
;
9119 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9120 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9121 = disp_del_at_next_stop
;
9123 /* See save_infcall_control_state for info on stop_bpstat. */
9124 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9129 /* restore_inferior_ptid() will be used by the cleanup machinery
9130 to restore the inferior_ptid value saved in a call to
9131 save_inferior_ptid(). */
9134 restore_inferior_ptid (void *arg
)
9136 ptid_t
*saved_ptid_ptr
= (ptid_t
*) arg
;
9138 inferior_ptid
= *saved_ptid_ptr
;
9142 /* Save the value of inferior_ptid so that it may be restored by a
9143 later call to do_cleanups(). Returns the struct cleanup pointer
9144 needed for later doing the cleanup. */
9147 save_inferior_ptid (void)
9149 ptid_t
*saved_ptid_ptr
= XNEW (ptid_t
);
9151 *saved_ptid_ptr
= inferior_ptid
;
9152 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
9158 clear_exit_convenience_vars (void)
9160 clear_internalvar (lookup_internalvar ("_exitsignal"));
9161 clear_internalvar (lookup_internalvar ("_exitcode"));
9165 /* User interface for reverse debugging:
9166 Set exec-direction / show exec-direction commands
9167 (returns error unless target implements to_set_exec_direction method). */
9169 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9170 static const char exec_forward
[] = "forward";
9171 static const char exec_reverse
[] = "reverse";
9172 static const char *exec_direction
= exec_forward
;
9173 static const char *const exec_direction_names
[] = {
9180 set_exec_direction_func (char *args
, int from_tty
,
9181 struct cmd_list_element
*cmd
)
9183 if (target_can_execute_reverse
)
9185 if (!strcmp (exec_direction
, exec_forward
))
9186 execution_direction
= EXEC_FORWARD
;
9187 else if (!strcmp (exec_direction
, exec_reverse
))
9188 execution_direction
= EXEC_REVERSE
;
9192 exec_direction
= exec_forward
;
9193 error (_("Target does not support this operation."));
9198 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9199 struct cmd_list_element
*cmd
, const char *value
)
9201 switch (execution_direction
) {
9203 fprintf_filtered (out
, _("Forward.\n"));
9206 fprintf_filtered (out
, _("Reverse.\n"));
9209 internal_error (__FILE__
, __LINE__
,
9210 _("bogus execution_direction value: %d"),
9211 (int) execution_direction
);
9216 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9217 struct cmd_list_element
*c
, const char *value
)
9219 fprintf_filtered (file
, _("Resuming the execution of threads "
9220 "of all processes is %s.\n"), value
);
9223 /* Implementation of `siginfo' variable. */
9225 static const struct internalvar_funcs siginfo_funcs
=
9232 /* Callback for infrun's target events source. This is marked when a
9233 thread has a pending status to process. */
9236 infrun_async_inferior_event_handler (gdb_client_data data
)
9238 inferior_event_handler (INF_REG_EVENT
, NULL
);
9242 _initialize_infrun (void)
9246 struct cmd_list_element
*c
;
9248 /* Register extra event sources in the event loop. */
9249 infrun_async_inferior_event_token
9250 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9252 add_info ("signals", signals_info
, _("\
9253 What debugger does when program gets various signals.\n\
9254 Specify a signal as argument to print info on that signal only."));
9255 add_info_alias ("handle", "signals", 0);
9257 c
= add_com ("handle", class_run
, handle_command
, _("\
9258 Specify how to handle signals.\n\
9259 Usage: handle SIGNAL [ACTIONS]\n\
9260 Args are signals and actions to apply to those signals.\n\
9261 If no actions are specified, the current settings for the specified signals\n\
9262 will be displayed instead.\n\
9264 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9265 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9266 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9267 The special arg \"all\" is recognized to mean all signals except those\n\
9268 used by the debugger, typically SIGTRAP and SIGINT.\n\
9270 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9271 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9272 Stop means reenter debugger if this signal happens (implies print).\n\
9273 Print means print a message if this signal happens.\n\
9274 Pass means let program see this signal; otherwise program doesn't know.\n\
9275 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9276 Pass and Stop may be combined.\n\
9278 Multiple signals may be specified. Signal numbers and signal names\n\
9279 may be interspersed with actions, with the actions being performed for\n\
9280 all signals cumulatively specified."));
9281 set_cmd_completer (c
, handle_completer
);
9284 stop_command
= add_cmd ("stop", class_obscure
,
9285 not_just_help_class_command
, _("\
9286 There is no `stop' command, but you can set a hook on `stop'.\n\
9287 This allows you to set a list of commands to be run each time execution\n\
9288 of the program stops."), &cmdlist
);
9290 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9291 Set inferior debugging."), _("\
9292 Show inferior debugging."), _("\
9293 When non-zero, inferior specific debugging is enabled."),
9296 &setdebuglist
, &showdebuglist
);
9298 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9299 &debug_displaced
, _("\
9300 Set displaced stepping debugging."), _("\
9301 Show displaced stepping debugging."), _("\
9302 When non-zero, displaced stepping specific debugging is enabled."),
9304 show_debug_displaced
,
9305 &setdebuglist
, &showdebuglist
);
9307 add_setshow_boolean_cmd ("non-stop", no_class
,
9309 Set whether gdb controls the inferior in non-stop mode."), _("\
9310 Show whether gdb controls the inferior in non-stop mode."), _("\
9311 When debugging a multi-threaded program and this setting is\n\
9312 off (the default, also called all-stop mode), when one thread stops\n\
9313 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9314 all other threads in the program while you interact with the thread of\n\
9315 interest. When you continue or step a thread, you can allow the other\n\
9316 threads to run, or have them remain stopped, but while you inspect any\n\
9317 thread's state, all threads stop.\n\
9319 In non-stop mode, when one thread stops, other threads can continue\n\
9320 to run freely. You'll be able to step each thread independently,\n\
9321 leave it stopped or free to run as needed."),
9327 numsigs
= (int) GDB_SIGNAL_LAST
;
9328 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9329 signal_print
= XNEWVEC (unsigned char, numsigs
);
9330 signal_program
= XNEWVEC (unsigned char, numsigs
);
9331 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9332 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9333 for (i
= 0; i
< numsigs
; i
++)
9336 signal_print
[i
] = 1;
9337 signal_program
[i
] = 1;
9338 signal_catch
[i
] = 0;
9341 /* Signals caused by debugger's own actions should not be given to
9342 the program afterwards.
9344 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9345 explicitly specifies that it should be delivered to the target
9346 program. Typically, that would occur when a user is debugging a
9347 target monitor on a simulator: the target monitor sets a
9348 breakpoint; the simulator encounters this breakpoint and halts
9349 the simulation handing control to GDB; GDB, noting that the stop
9350 address doesn't map to any known breakpoint, returns control back
9351 to the simulator; the simulator then delivers the hardware
9352 equivalent of a GDB_SIGNAL_TRAP to the program being
9354 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9355 signal_program
[GDB_SIGNAL_INT
] = 0;
9357 /* Signals that are not errors should not normally enter the debugger. */
9358 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9359 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9360 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9361 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9362 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9363 signal_print
[GDB_SIGNAL_PROF
] = 0;
9364 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9365 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9366 signal_stop
[GDB_SIGNAL_IO
] = 0;
9367 signal_print
[GDB_SIGNAL_IO
] = 0;
9368 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9369 signal_print
[GDB_SIGNAL_POLL
] = 0;
9370 signal_stop
[GDB_SIGNAL_URG
] = 0;
9371 signal_print
[GDB_SIGNAL_URG
] = 0;
9372 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9373 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9374 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9375 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9377 /* These signals are used internally by user-level thread
9378 implementations. (See signal(5) on Solaris.) Like the above
9379 signals, a healthy program receives and handles them as part of
9380 its normal operation. */
9381 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9382 signal_print
[GDB_SIGNAL_LWP
] = 0;
9383 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9384 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9385 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9386 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9387 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9388 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9390 /* Update cached state. */
9391 signal_cache_update (-1);
9393 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9394 &stop_on_solib_events
, _("\
9395 Set stopping for shared library events."), _("\
9396 Show stopping for shared library events."), _("\
9397 If nonzero, gdb will give control to the user when the dynamic linker\n\
9398 notifies gdb of shared library events. The most common event of interest\n\
9399 to the user would be loading/unloading of a new library."),
9400 set_stop_on_solib_events
,
9401 show_stop_on_solib_events
,
9402 &setlist
, &showlist
);
9404 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9405 follow_fork_mode_kind_names
,
9406 &follow_fork_mode_string
, _("\
9407 Set debugger response to a program call of fork or vfork."), _("\
9408 Show debugger response to a program call of fork or vfork."), _("\
9409 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9410 parent - the original process is debugged after a fork\n\
9411 child - the new process is debugged after a fork\n\
9412 The unfollowed process will continue to run.\n\
9413 By default, the debugger will follow the parent process."),
9415 show_follow_fork_mode_string
,
9416 &setlist
, &showlist
);
9418 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9419 follow_exec_mode_names
,
9420 &follow_exec_mode_string
, _("\
9421 Set debugger response to a program call of exec."), _("\
9422 Show debugger response to a program call of exec."), _("\
9423 An exec call replaces the program image of a process.\n\
9425 follow-exec-mode can be:\n\
9427 new - the debugger creates a new inferior and rebinds the process\n\
9428 to this new inferior. The program the process was running before\n\
9429 the exec call can be restarted afterwards by restarting the original\n\
9432 same - the debugger keeps the process bound to the same inferior.\n\
9433 The new executable image replaces the previous executable loaded in\n\
9434 the inferior. Restarting the inferior after the exec call restarts\n\
9435 the executable the process was running after the exec call.\n\
9437 By default, the debugger will use the same inferior."),
9439 show_follow_exec_mode_string
,
9440 &setlist
, &showlist
);
9442 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9443 scheduler_enums
, &scheduler_mode
, _("\
9444 Set mode for locking scheduler during execution."), _("\
9445 Show mode for locking scheduler during execution."), _("\
9446 off == no locking (threads may preempt at any time)\n\
9447 on == full locking (no thread except the current thread may run)\n\
9448 This applies to both normal execution and replay mode.\n\
9449 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9450 In this mode, other threads may run during other commands.\n\
9451 This applies to both normal execution and replay mode.\n\
9452 replay == scheduler locked in replay mode and unlocked during normal execution."),
9453 set_schedlock_func
, /* traps on target vector */
9454 show_scheduler_mode
,
9455 &setlist
, &showlist
);
9457 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9458 Set mode for resuming threads of all processes."), _("\
9459 Show mode for resuming threads of all processes."), _("\
9460 When on, execution commands (such as 'continue' or 'next') resume all\n\
9461 threads of all processes. When off (which is the default), execution\n\
9462 commands only resume the threads of the current process. The set of\n\
9463 threads that are resumed is further refined by the scheduler-locking\n\
9464 mode (see help set scheduler-locking)."),
9466 show_schedule_multiple
,
9467 &setlist
, &showlist
);
9469 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9470 Set mode of the step operation."), _("\
9471 Show mode of the step operation."), _("\
9472 When set, doing a step over a function without debug line information\n\
9473 will stop at the first instruction of that function. Otherwise, the\n\
9474 function is skipped and the step command stops at a different source line."),
9476 show_step_stop_if_no_debug
,
9477 &setlist
, &showlist
);
9479 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9480 &can_use_displaced_stepping
, _("\
9481 Set debugger's willingness to use displaced stepping."), _("\
9482 Show debugger's willingness to use displaced stepping."), _("\
9483 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9484 supported by the target architecture. If off, gdb will not use displaced\n\
9485 stepping to step over breakpoints, even if such is supported by the target\n\
9486 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9487 if the target architecture supports it and non-stop mode is active, but will not\n\
9488 use it in all-stop mode (see help set non-stop)."),
9490 show_can_use_displaced_stepping
,
9491 &setlist
, &showlist
);
9493 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9494 &exec_direction
, _("Set direction of execution.\n\
9495 Options are 'forward' or 'reverse'."),
9496 _("Show direction of execution (forward/reverse)."),
9497 _("Tells gdb whether to execute forward or backward."),
9498 set_exec_direction_func
, show_exec_direction_func
,
9499 &setlist
, &showlist
);
9501 /* Set/show detach-on-fork: user-settable mode. */
9503 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9504 Set whether gdb will detach the child of a fork."), _("\
9505 Show whether gdb will detach the child of a fork."), _("\
9506 Tells gdb whether to detach the child of a fork."),
9507 NULL
, NULL
, &setlist
, &showlist
);
9509 /* Set/show disable address space randomization mode. */
9511 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9512 &disable_randomization
, _("\
9513 Set disabling of debuggee's virtual address space randomization."), _("\
9514 Show disabling of debuggee's virtual address space randomization."), _("\
9515 When this mode is on (which is the default), randomization of the virtual\n\
9516 address space is disabled. Standalone programs run with the randomization\n\
9517 enabled by default on some platforms."),
9518 &set_disable_randomization
,
9519 &show_disable_randomization
,
9520 &setlist
, &showlist
);
9522 /* ptid initializations */
9523 inferior_ptid
= null_ptid
;
9524 target_last_wait_ptid
= minus_one_ptid
;
9526 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9527 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9528 observer_attach_thread_exit (infrun_thread_thread_exit
);
9529 observer_attach_inferior_exit (infrun_inferior_exit
);
9531 /* Explicitly create without lookup, since that tries to create a
9532 value with a void typed value, and when we get here, gdbarch
9533 isn't initialized yet. At this point, we're quite sure there
9534 isn't another convenience variable of the same name. */
9535 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9537 add_setshow_boolean_cmd ("observer", no_class
,
9538 &observer_mode_1
, _("\
9539 Set whether gdb controls the inferior in observer mode."), _("\
9540 Show whether gdb controls the inferior in observer mode."), _("\
9541 In observer mode, GDB can get data from the inferior, but not\n\
9542 affect its execution. Registers and memory may not be changed,\n\
9543 breakpoints may not be set, and the program cannot be interrupted\n\