1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2017 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 #include "event-loop.h"
65 #include "thread-fsm.h"
66 #include "common/enum-flags.h"
68 /* Prototypes for local functions */
70 static void signals_info (char *, int);
72 static void handle_command (char *, int);
74 static void sig_print_info (enum gdb_signal
);
76 static void sig_print_header (void);
78 static void resume_cleanups (void *);
80 static int hook_stop_stub (void *);
82 static int restore_selected_frame (void *);
84 static int follow_fork (void);
86 static int follow_fork_inferior (int follow_child
, int detach_fork
);
88 static void follow_inferior_reset_breakpoints (void);
90 static void set_schedlock_func (char *args
, int from_tty
,
91 struct cmd_list_element
*c
);
93 static int currently_stepping (struct thread_info
*tp
);
95 void _initialize_infrun (void);
97 void nullify_last_target_wait_ptid (void);
99 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
101 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
103 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
105 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
107 /* Asynchronous signal handler registered as event loop source for
108 when we have pending events ready to be passed to the core. */
109 static struct async_event_handler
*infrun_async_inferior_event_token
;
111 /* Stores whether infrun_async was previously enabled or disabled.
112 Starts off as -1, indicating "never enabled/disabled". */
113 static int infrun_is_async
= -1;
118 infrun_async (int enable
)
120 if (infrun_is_async
!= enable
)
122 infrun_is_async
= enable
;
125 fprintf_unfiltered (gdb_stdlog
,
126 "infrun: infrun_async(%d)\n",
130 mark_async_event_handler (infrun_async_inferior_event_token
);
132 clear_async_event_handler (infrun_async_inferior_event_token
);
139 mark_infrun_async_event_handler (void)
141 mark_async_event_handler (infrun_async_inferior_event_token
);
144 /* When set, stop the 'step' command if we enter a function which has
145 no line number information. The normal behavior is that we step
146 over such function. */
147 int step_stop_if_no_debug
= 0;
149 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
150 struct cmd_list_element
*c
, const char *value
)
152 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
155 /* proceed and normal_stop use this to notify the user when the
156 inferior stopped in a different thread than it had been running
159 static ptid_t previous_inferior_ptid
;
161 /* If set (default for legacy reasons), when following a fork, GDB
162 will detach from one of the fork branches, child or parent.
163 Exactly which branch is detached depends on 'set follow-fork-mode'
166 static int detach_fork
= 1;
168 int debug_displaced
= 0;
170 show_debug_displaced (struct ui_file
*file
, int from_tty
,
171 struct cmd_list_element
*c
, const char *value
)
173 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
176 unsigned int debug_infrun
= 0;
178 show_debug_infrun (struct ui_file
*file
, int from_tty
,
179 struct cmd_list_element
*c
, const char *value
)
181 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
185 /* Support for disabling address space randomization. */
187 int disable_randomization
= 1;
190 show_disable_randomization (struct ui_file
*file
, int from_tty
,
191 struct cmd_list_element
*c
, const char *value
)
193 if (target_supports_disable_randomization ())
194 fprintf_filtered (file
,
195 _("Disabling randomization of debuggee's "
196 "virtual address space is %s.\n"),
199 fputs_filtered (_("Disabling randomization of debuggee's "
200 "virtual address space is unsupported on\n"
201 "this platform.\n"), file
);
205 set_disable_randomization (char *args
, int from_tty
,
206 struct cmd_list_element
*c
)
208 if (!target_supports_disable_randomization ())
209 error (_("Disabling randomization of debuggee's "
210 "virtual address space is unsupported on\n"
214 /* User interface for non-stop mode. */
217 static int non_stop_1
= 0;
220 set_non_stop (char *args
, int from_tty
,
221 struct cmd_list_element
*c
)
223 if (target_has_execution
)
225 non_stop_1
= non_stop
;
226 error (_("Cannot change this setting while the inferior is running."));
229 non_stop
= non_stop_1
;
233 show_non_stop (struct ui_file
*file
, int from_tty
,
234 struct cmd_list_element
*c
, const char *value
)
236 fprintf_filtered (file
,
237 _("Controlling the inferior in non-stop mode is %s.\n"),
241 /* "Observer mode" is somewhat like a more extreme version of
242 non-stop, in which all GDB operations that might affect the
243 target's execution have been disabled. */
245 int observer_mode
= 0;
246 static int observer_mode_1
= 0;
249 set_observer_mode (char *args
, int from_tty
,
250 struct cmd_list_element
*c
)
252 if (target_has_execution
)
254 observer_mode_1
= observer_mode
;
255 error (_("Cannot change this setting while the inferior is running."));
258 observer_mode
= observer_mode_1
;
260 may_write_registers
= !observer_mode
;
261 may_write_memory
= !observer_mode
;
262 may_insert_breakpoints
= !observer_mode
;
263 may_insert_tracepoints
= !observer_mode
;
264 /* We can insert fast tracepoints in or out of observer mode,
265 but enable them if we're going into this mode. */
267 may_insert_fast_tracepoints
= 1;
268 may_stop
= !observer_mode
;
269 update_target_permissions ();
271 /* Going *into* observer mode we must force non-stop, then
272 going out we leave it that way. */
275 pagination_enabled
= 0;
276 non_stop
= non_stop_1
= 1;
280 printf_filtered (_("Observer mode is now %s.\n"),
281 (observer_mode
? "on" : "off"));
285 show_observer_mode (struct ui_file
*file
, int from_tty
,
286 struct cmd_list_element
*c
, const char *value
)
288 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
291 /* This updates the value of observer mode based on changes in
292 permissions. Note that we are deliberately ignoring the values of
293 may-write-registers and may-write-memory, since the user may have
294 reason to enable these during a session, for instance to turn on a
295 debugging-related global. */
298 update_observer_mode (void)
302 newval
= (!may_insert_breakpoints
303 && !may_insert_tracepoints
304 && may_insert_fast_tracepoints
308 /* Let the user know if things change. */
309 if (newval
!= observer_mode
)
310 printf_filtered (_("Observer mode is now %s.\n"),
311 (newval
? "on" : "off"));
313 observer_mode
= observer_mode_1
= newval
;
316 /* Tables of how to react to signals; the user sets them. */
318 static unsigned char *signal_stop
;
319 static unsigned char *signal_print
;
320 static unsigned char *signal_program
;
322 /* Table of signals that are registered with "catch signal". A
323 non-zero entry indicates that the signal is caught by some "catch
324 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
326 static unsigned char *signal_catch
;
328 /* Table of signals that the target may silently handle.
329 This is automatically determined from the flags above,
330 and simply cached here. */
331 static unsigned char *signal_pass
;
333 #define SET_SIGS(nsigs,sigs,flags) \
335 int signum = (nsigs); \
336 while (signum-- > 0) \
337 if ((sigs)[signum]) \
338 (flags)[signum] = 1; \
341 #define UNSET_SIGS(nsigs,sigs,flags) \
343 int signum = (nsigs); \
344 while (signum-- > 0) \
345 if ((sigs)[signum]) \
346 (flags)[signum] = 0; \
349 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
350 this function is to avoid exporting `signal_program'. */
353 update_signals_program_target (void)
355 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
358 /* Value to pass to target_resume() to cause all threads to resume. */
360 #define RESUME_ALL minus_one_ptid
362 /* Command list pointer for the "stop" placeholder. */
364 static struct cmd_list_element
*stop_command
;
366 /* Nonzero if we want to give control to the user when we're notified
367 of shared library events by the dynamic linker. */
368 int stop_on_solib_events
;
370 /* Enable or disable optional shared library event breakpoints
371 as appropriate when the above flag is changed. */
374 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
376 update_solib_breakpoints ();
380 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
381 struct cmd_list_element
*c
, const char *value
)
383 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
387 /* Nonzero after stop if current stack frame should be printed. */
389 static int stop_print_frame
;
391 /* This is a cached copy of the pid/waitstatus of the last event
392 returned by target_wait()/deprecated_target_wait_hook(). This
393 information is returned by get_last_target_status(). */
394 static ptid_t target_last_wait_ptid
;
395 static struct target_waitstatus target_last_waitstatus
;
397 static void context_switch (ptid_t ptid
);
399 void init_thread_stepping_state (struct thread_info
*tss
);
401 static const char follow_fork_mode_child
[] = "child";
402 static const char follow_fork_mode_parent
[] = "parent";
404 static const char *const follow_fork_mode_kind_names
[] = {
405 follow_fork_mode_child
,
406 follow_fork_mode_parent
,
410 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
412 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
413 struct cmd_list_element
*c
, const char *value
)
415 fprintf_filtered (file
,
416 _("Debugger response to a program "
417 "call of fork or vfork is \"%s\".\n"),
422 /* Handle changes to the inferior list based on the type of fork,
423 which process is being followed, and whether the other process
424 should be detached. On entry inferior_ptid must be the ptid of
425 the fork parent. At return inferior_ptid is the ptid of the
426 followed inferior. */
429 follow_fork_inferior (int follow_child
, int detach_fork
)
432 ptid_t parent_ptid
, child_ptid
;
434 has_vforked
= (inferior_thread ()->pending_follow
.kind
435 == TARGET_WAITKIND_VFORKED
);
436 parent_ptid
= inferior_ptid
;
437 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
440 && !non_stop
/* Non-stop always resumes both branches. */
441 && current_ui
->prompt_state
== PROMPT_BLOCKED
442 && !(follow_child
|| detach_fork
|| sched_multi
))
444 /* The parent stays blocked inside the vfork syscall until the
445 child execs or exits. If we don't let the child run, then
446 the parent stays blocked. If we're telling the parent to run
447 in the foreground, the user will not be able to ctrl-c to get
448 back the terminal, effectively hanging the debug session. */
449 fprintf_filtered (gdb_stderr
, _("\
450 Can not resume the parent process over vfork in the foreground while\n\
451 holding the child stopped. Try \"set detach-on-fork\" or \
452 \"set schedule-multiple\".\n"));
453 /* FIXME output string > 80 columns. */
459 /* Detach new forked process? */
462 /* Before detaching from the child, remove all breakpoints
463 from it. If we forked, then this has already been taken
464 care of by infrun.c. If we vforked however, any
465 breakpoint inserted in the parent is visible in the
466 child, even those added while stopped in a vfork
467 catchpoint. This will remove the breakpoints from the
468 parent also, but they'll be reinserted below. */
471 /* Keep breakpoints list in sync. */
472 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
475 if (info_verbose
|| debug_infrun
)
477 /* Ensure that we have a process ptid. */
478 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
480 target_terminal_ours_for_output ();
481 fprintf_filtered (gdb_stdlog
,
482 _("Detaching after %s from child %s.\n"),
483 has_vforked
? "vfork" : "fork",
484 target_pid_to_str (process_ptid
));
489 struct inferior
*parent_inf
, *child_inf
;
490 struct cleanup
*old_chain
;
492 /* Add process to GDB's tables. */
493 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
495 parent_inf
= current_inferior ();
496 child_inf
->attach_flag
= parent_inf
->attach_flag
;
497 copy_terminal_info (child_inf
, parent_inf
);
498 child_inf
->gdbarch
= parent_inf
->gdbarch
;
499 copy_inferior_target_desc_info (child_inf
, parent_inf
);
501 old_chain
= save_inferior_ptid ();
502 save_current_program_space ();
504 inferior_ptid
= child_ptid
;
505 add_thread (inferior_ptid
);
506 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
508 /* If this is a vfork child, then the address-space is
509 shared with the parent. */
512 child_inf
->pspace
= parent_inf
->pspace
;
513 child_inf
->aspace
= parent_inf
->aspace
;
515 /* The parent will be frozen until the child is done
516 with the shared region. Keep track of the
518 child_inf
->vfork_parent
= parent_inf
;
519 child_inf
->pending_detach
= 0;
520 parent_inf
->vfork_child
= child_inf
;
521 parent_inf
->pending_detach
= 0;
525 child_inf
->aspace
= new_address_space ();
526 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
527 child_inf
->removable
= 1;
528 set_current_program_space (child_inf
->pspace
);
529 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
531 /* Let the shared library layer (e.g., solib-svr4) learn
532 about this new process, relocate the cloned exec, pull
533 in shared libraries, and install the solib event
534 breakpoint. If a "cloned-VM" event was propagated
535 better throughout the core, this wouldn't be
537 solib_create_inferior_hook (0);
540 do_cleanups (old_chain
);
545 struct inferior
*parent_inf
;
547 parent_inf
= current_inferior ();
549 /* If we detached from the child, then we have to be careful
550 to not insert breakpoints in the parent until the child
551 is done with the shared memory region. However, if we're
552 staying attached to the child, then we can and should
553 insert breakpoints, so that we can debug it. A
554 subsequent child exec or exit is enough to know when does
555 the child stops using the parent's address space. */
556 parent_inf
->waiting_for_vfork_done
= detach_fork
;
557 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
562 /* Follow the child. */
563 struct inferior
*parent_inf
, *child_inf
;
564 struct program_space
*parent_pspace
;
566 if (info_verbose
|| debug_infrun
)
568 target_terminal_ours_for_output ();
569 fprintf_filtered (gdb_stdlog
,
570 _("Attaching after %s %s to child %s.\n"),
571 target_pid_to_str (parent_ptid
),
572 has_vforked
? "vfork" : "fork",
573 target_pid_to_str (child_ptid
));
576 /* Add the new inferior first, so that the target_detach below
577 doesn't unpush the target. */
579 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
581 parent_inf
= current_inferior ();
582 child_inf
->attach_flag
= parent_inf
->attach_flag
;
583 copy_terminal_info (child_inf
, parent_inf
);
584 child_inf
->gdbarch
= parent_inf
->gdbarch
;
585 copy_inferior_target_desc_info (child_inf
, parent_inf
);
587 parent_pspace
= parent_inf
->pspace
;
589 /* If we're vforking, we want to hold on to the parent until the
590 child exits or execs. At child exec or exit time we can
591 remove the old breakpoints from the parent and detach or
592 resume debugging it. Otherwise, detach the parent now; we'll
593 want to reuse it's program/address spaces, but we can't set
594 them to the child before removing breakpoints from the
595 parent, otherwise, the breakpoints module could decide to
596 remove breakpoints from the wrong process (since they'd be
597 assigned to the same address space). */
601 gdb_assert (child_inf
->vfork_parent
== NULL
);
602 gdb_assert (parent_inf
->vfork_child
== NULL
);
603 child_inf
->vfork_parent
= parent_inf
;
604 child_inf
->pending_detach
= 0;
605 parent_inf
->vfork_child
= child_inf
;
606 parent_inf
->pending_detach
= detach_fork
;
607 parent_inf
->waiting_for_vfork_done
= 0;
609 else if (detach_fork
)
611 if (info_verbose
|| debug_infrun
)
613 /* Ensure that we have a process ptid. */
614 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
616 target_terminal_ours_for_output ();
617 fprintf_filtered (gdb_stdlog
,
618 _("Detaching after fork from "
620 target_pid_to_str (process_ptid
));
623 target_detach (NULL
, 0);
626 /* Note that the detach above makes PARENT_INF dangling. */
628 /* Add the child thread to the appropriate lists, and switch to
629 this new thread, before cloning the program space, and
630 informing the solib layer about this new process. */
632 inferior_ptid
= child_ptid
;
633 add_thread (inferior_ptid
);
635 /* If this is a vfork child, then the address-space is shared
636 with the parent. If we detached from the parent, then we can
637 reuse the parent's program/address spaces. */
638 if (has_vforked
|| detach_fork
)
640 child_inf
->pspace
= parent_pspace
;
641 child_inf
->aspace
= child_inf
->pspace
->aspace
;
645 child_inf
->aspace
= new_address_space ();
646 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
647 child_inf
->removable
= 1;
648 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
649 set_current_program_space (child_inf
->pspace
);
650 clone_program_space (child_inf
->pspace
, parent_pspace
);
652 /* Let the shared library layer (e.g., solib-svr4) learn
653 about this new process, relocate the cloned exec, pull in
654 shared libraries, and install the solib event breakpoint.
655 If a "cloned-VM" event was propagated better throughout
656 the core, this wouldn't be required. */
657 solib_create_inferior_hook (0);
661 return target_follow_fork (follow_child
, detach_fork
);
664 /* Tell the target to follow the fork we're stopped at. Returns true
665 if the inferior should be resumed; false, if the target for some
666 reason decided it's best not to resume. */
671 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
672 int should_resume
= 1;
673 struct thread_info
*tp
;
675 /* Copy user stepping state to the new inferior thread. FIXME: the
676 followed fork child thread should have a copy of most of the
677 parent thread structure's run control related fields, not just these.
678 Initialized to avoid "may be used uninitialized" warnings from gcc. */
679 struct breakpoint
*step_resume_breakpoint
= NULL
;
680 struct breakpoint
*exception_resume_breakpoint
= NULL
;
681 CORE_ADDR step_range_start
= 0;
682 CORE_ADDR step_range_end
= 0;
683 struct frame_id step_frame_id
= { 0 };
684 struct thread_fsm
*thread_fsm
= NULL
;
689 struct target_waitstatus wait_status
;
691 /* Get the last target status returned by target_wait(). */
692 get_last_target_status (&wait_ptid
, &wait_status
);
694 /* If not stopped at a fork event, then there's nothing else to
696 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
697 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
700 /* Check if we switched over from WAIT_PTID, since the event was
702 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
703 && !ptid_equal (inferior_ptid
, wait_ptid
))
705 /* We did. Switch back to WAIT_PTID thread, to tell the
706 target to follow it (in either direction). We'll
707 afterwards refuse to resume, and inform the user what
709 switch_to_thread (wait_ptid
);
714 tp
= inferior_thread ();
716 /* If there were any forks/vforks that were caught and are now to be
717 followed, then do so now. */
718 switch (tp
->pending_follow
.kind
)
720 case TARGET_WAITKIND_FORKED
:
721 case TARGET_WAITKIND_VFORKED
:
723 ptid_t parent
, child
;
725 /* If the user did a next/step, etc, over a fork call,
726 preserve the stepping state in the fork child. */
727 if (follow_child
&& should_resume
)
729 step_resume_breakpoint
= clone_momentary_breakpoint
730 (tp
->control
.step_resume_breakpoint
);
731 step_range_start
= tp
->control
.step_range_start
;
732 step_range_end
= tp
->control
.step_range_end
;
733 step_frame_id
= tp
->control
.step_frame_id
;
734 exception_resume_breakpoint
735 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
736 thread_fsm
= tp
->thread_fsm
;
738 /* For now, delete the parent's sr breakpoint, otherwise,
739 parent/child sr breakpoints are considered duplicates,
740 and the child version will not be installed. Remove
741 this when the breakpoints module becomes aware of
742 inferiors and address spaces. */
743 delete_step_resume_breakpoint (tp
);
744 tp
->control
.step_range_start
= 0;
745 tp
->control
.step_range_end
= 0;
746 tp
->control
.step_frame_id
= null_frame_id
;
747 delete_exception_resume_breakpoint (tp
);
748 tp
->thread_fsm
= NULL
;
751 parent
= inferior_ptid
;
752 child
= tp
->pending_follow
.value
.related_pid
;
754 /* Set up inferior(s) as specified by the caller, and tell the
755 target to do whatever is necessary to follow either parent
757 if (follow_fork_inferior (follow_child
, detach_fork
))
759 /* Target refused to follow, or there's some other reason
760 we shouldn't resume. */
765 /* This pending follow fork event is now handled, one way
766 or another. The previous selected thread may be gone
767 from the lists by now, but if it is still around, need
768 to clear the pending follow request. */
769 tp
= find_thread_ptid (parent
);
771 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
773 /* This makes sure we don't try to apply the "Switched
774 over from WAIT_PID" logic above. */
775 nullify_last_target_wait_ptid ();
777 /* If we followed the child, switch to it... */
780 switch_to_thread (child
);
782 /* ... and preserve the stepping state, in case the
783 user was stepping over the fork call. */
786 tp
= inferior_thread ();
787 tp
->control
.step_resume_breakpoint
788 = step_resume_breakpoint
;
789 tp
->control
.step_range_start
= step_range_start
;
790 tp
->control
.step_range_end
= step_range_end
;
791 tp
->control
.step_frame_id
= step_frame_id
;
792 tp
->control
.exception_resume_breakpoint
793 = exception_resume_breakpoint
;
794 tp
->thread_fsm
= thread_fsm
;
798 /* If we get here, it was because we're trying to
799 resume from a fork catchpoint, but, the user
800 has switched threads away from the thread that
801 forked. In that case, the resume command
802 issued is most likely not applicable to the
803 child, so just warn, and refuse to resume. */
804 warning (_("Not resuming: switched threads "
805 "before following fork child."));
808 /* Reset breakpoints in the child as appropriate. */
809 follow_inferior_reset_breakpoints ();
812 switch_to_thread (parent
);
816 case TARGET_WAITKIND_SPURIOUS
:
817 /* Nothing to follow. */
820 internal_error (__FILE__
, __LINE__
,
821 "Unexpected pending_follow.kind %d\n",
822 tp
->pending_follow
.kind
);
826 return should_resume
;
830 follow_inferior_reset_breakpoints (void)
832 struct thread_info
*tp
= inferior_thread ();
834 /* Was there a step_resume breakpoint? (There was if the user
835 did a "next" at the fork() call.) If so, explicitly reset its
836 thread number. Cloned step_resume breakpoints are disabled on
837 creation, so enable it here now that it is associated with the
840 step_resumes are a form of bp that are made to be per-thread.
841 Since we created the step_resume bp when the parent process
842 was being debugged, and now are switching to the child process,
843 from the breakpoint package's viewpoint, that's a switch of
844 "threads". We must update the bp's notion of which thread
845 it is for, or it'll be ignored when it triggers. */
847 if (tp
->control
.step_resume_breakpoint
)
849 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
850 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
853 /* Treat exception_resume breakpoints like step_resume breakpoints. */
854 if (tp
->control
.exception_resume_breakpoint
)
856 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
857 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
860 /* Reinsert all breakpoints in the child. The user may have set
861 breakpoints after catching the fork, in which case those
862 were never set in the child, but only in the parent. This makes
863 sure the inserted breakpoints match the breakpoint list. */
865 breakpoint_re_set ();
866 insert_breakpoints ();
869 /* The child has exited or execed: resume threads of the parent the
870 user wanted to be executing. */
873 proceed_after_vfork_done (struct thread_info
*thread
,
876 int pid
= * (int *) arg
;
878 if (ptid_get_pid (thread
->ptid
) == pid
879 && is_running (thread
->ptid
)
880 && !is_executing (thread
->ptid
)
881 && !thread
->stop_requested
882 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
885 fprintf_unfiltered (gdb_stdlog
,
886 "infrun: resuming vfork parent thread %s\n",
887 target_pid_to_str (thread
->ptid
));
889 switch_to_thread (thread
->ptid
);
890 clear_proceed_status (0);
891 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
897 /* Called whenever we notice an exec or exit event, to handle
898 detaching or resuming a vfork parent. */
901 handle_vfork_child_exec_or_exit (int exec
)
903 struct inferior
*inf
= current_inferior ();
905 if (inf
->vfork_parent
)
907 int resume_parent
= -1;
909 /* This exec or exit marks the end of the shared memory region
910 between the parent and the child. If the user wanted to
911 detach from the parent, now is the time. */
913 if (inf
->vfork_parent
->pending_detach
)
915 struct thread_info
*tp
;
916 struct cleanup
*old_chain
;
917 struct program_space
*pspace
;
918 struct address_space
*aspace
;
920 /* follow-fork child, detach-on-fork on. */
922 inf
->vfork_parent
->pending_detach
= 0;
926 /* If we're handling a child exit, then inferior_ptid
927 points at the inferior's pid, not to a thread. */
928 old_chain
= save_inferior_ptid ();
929 save_current_program_space ();
930 save_current_inferior ();
933 old_chain
= save_current_space_and_thread ();
935 /* We're letting loose of the parent. */
936 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
937 switch_to_thread (tp
->ptid
);
939 /* We're about to detach from the parent, which implicitly
940 removes breakpoints from its address space. There's a
941 catch here: we want to reuse the spaces for the child,
942 but, parent/child are still sharing the pspace at this
943 point, although the exec in reality makes the kernel give
944 the child a fresh set of new pages. The problem here is
945 that the breakpoints module being unaware of this, would
946 likely chose the child process to write to the parent
947 address space. Swapping the child temporarily away from
948 the spaces has the desired effect. Yes, this is "sort
951 pspace
= inf
->pspace
;
952 aspace
= inf
->aspace
;
956 if (debug_infrun
|| info_verbose
)
958 target_terminal_ours_for_output ();
962 fprintf_filtered (gdb_stdlog
,
963 _("Detaching vfork parent process "
964 "%d after child exec.\n"),
965 inf
->vfork_parent
->pid
);
969 fprintf_filtered (gdb_stdlog
,
970 _("Detaching vfork parent process "
971 "%d after child exit.\n"),
972 inf
->vfork_parent
->pid
);
976 target_detach (NULL
, 0);
979 inf
->pspace
= pspace
;
980 inf
->aspace
= aspace
;
982 do_cleanups (old_chain
);
986 /* We're staying attached to the parent, so, really give the
987 child a new address space. */
988 inf
->pspace
= add_program_space (maybe_new_address_space ());
989 inf
->aspace
= inf
->pspace
->aspace
;
991 set_current_program_space (inf
->pspace
);
993 resume_parent
= inf
->vfork_parent
->pid
;
995 /* Break the bonds. */
996 inf
->vfork_parent
->vfork_child
= NULL
;
1000 struct cleanup
*old_chain
;
1001 struct program_space
*pspace
;
1003 /* If this is a vfork child exiting, then the pspace and
1004 aspaces were shared with the parent. Since we're
1005 reporting the process exit, we'll be mourning all that is
1006 found in the address space, and switching to null_ptid,
1007 preparing to start a new inferior. But, since we don't
1008 want to clobber the parent's address/program spaces, we
1009 go ahead and create a new one for this exiting
1012 /* Switch to null_ptid, so that clone_program_space doesn't want
1013 to read the selected frame of a dead process. */
1014 old_chain
= save_inferior_ptid ();
1015 inferior_ptid
= null_ptid
;
1017 /* This inferior is dead, so avoid giving the breakpoints
1018 module the option to write through to it (cloning a
1019 program space resets breakpoints). */
1022 pspace
= add_program_space (maybe_new_address_space ());
1023 set_current_program_space (pspace
);
1025 inf
->symfile_flags
= SYMFILE_NO_READ
;
1026 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1027 inf
->pspace
= pspace
;
1028 inf
->aspace
= pspace
->aspace
;
1030 /* Put back inferior_ptid. We'll continue mourning this
1032 do_cleanups (old_chain
);
1034 resume_parent
= inf
->vfork_parent
->pid
;
1035 /* Break the bonds. */
1036 inf
->vfork_parent
->vfork_child
= NULL
;
1039 inf
->vfork_parent
= NULL
;
1041 gdb_assert (current_program_space
== inf
->pspace
);
1043 if (non_stop
&& resume_parent
!= -1)
1045 /* If the user wanted the parent to be running, let it go
1047 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1050 fprintf_unfiltered (gdb_stdlog
,
1051 "infrun: resuming vfork parent process %d\n",
1054 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1056 do_cleanups (old_chain
);
1061 /* Enum strings for "set|show follow-exec-mode". */
1063 static const char follow_exec_mode_new
[] = "new";
1064 static const char follow_exec_mode_same
[] = "same";
1065 static const char *const follow_exec_mode_names
[] =
1067 follow_exec_mode_new
,
1068 follow_exec_mode_same
,
1072 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1074 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1075 struct cmd_list_element
*c
, const char *value
)
1077 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1080 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1083 follow_exec (ptid_t ptid
, char *exec_file_target
)
1085 struct thread_info
*th
, *tmp
;
1086 struct inferior
*inf
= current_inferior ();
1087 int pid
= ptid_get_pid (ptid
);
1088 ptid_t process_ptid
;
1089 char *exec_file_host
;
1090 struct cleanup
*old_chain
;
1092 /* This is an exec event that we actually wish to pay attention to.
1093 Refresh our symbol table to the newly exec'd program, remove any
1094 momentary bp's, etc.
1096 If there are breakpoints, they aren't really inserted now,
1097 since the exec() transformed our inferior into a fresh set
1100 We want to preserve symbolic breakpoints on the list, since
1101 we have hopes that they can be reset after the new a.out's
1102 symbol table is read.
1104 However, any "raw" breakpoints must be removed from the list
1105 (e.g., the solib bp's), since their address is probably invalid
1108 And, we DON'T want to call delete_breakpoints() here, since
1109 that may write the bp's "shadow contents" (the instruction
1110 value that was overwritten witha TRAP instruction). Since
1111 we now have a new a.out, those shadow contents aren't valid. */
1113 mark_breakpoints_out ();
1115 /* The target reports the exec event to the main thread, even if
1116 some other thread does the exec, and even if the main thread was
1117 stopped or already gone. We may still have non-leader threads of
1118 the process on our list. E.g., on targets that don't have thread
1119 exit events (like remote); or on native Linux in non-stop mode if
1120 there were only two threads in the inferior and the non-leader
1121 one is the one that execs (and nothing forces an update of the
1122 thread list up to here). When debugging remotely, it's best to
1123 avoid extra traffic, when possible, so avoid syncing the thread
1124 list with the target, and instead go ahead and delete all threads
1125 of the process but one that reported the event. Note this must
1126 be done before calling update_breakpoints_after_exec, as
1127 otherwise clearing the threads' resources would reference stale
1128 thread breakpoints -- it may have been one of these threads that
1129 stepped across the exec. We could just clear their stepping
1130 states, but as long as we're iterating, might as well delete
1131 them. Deleting them now rather than at the next user-visible
1132 stop provides a nicer sequence of events for user and MI
1134 ALL_THREADS_SAFE (th
, tmp
)
1135 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1136 delete_thread (th
->ptid
);
1138 /* We also need to clear any left over stale state for the
1139 leader/event thread. E.g., if there was any step-resume
1140 breakpoint or similar, it's gone now. We cannot truly
1141 step-to-next statement through an exec(). */
1142 th
= inferior_thread ();
1143 th
->control
.step_resume_breakpoint
= NULL
;
1144 th
->control
.exception_resume_breakpoint
= NULL
;
1145 th
->control
.single_step_breakpoints
= NULL
;
1146 th
->control
.step_range_start
= 0;
1147 th
->control
.step_range_end
= 0;
1149 /* The user may have had the main thread held stopped in the
1150 previous image (e.g., schedlock on, or non-stop). Release
1152 th
->stop_requested
= 0;
1154 update_breakpoints_after_exec ();
1156 /* What is this a.out's name? */
1157 process_ptid
= pid_to_ptid (pid
);
1158 printf_unfiltered (_("%s is executing new program: %s\n"),
1159 target_pid_to_str (process_ptid
),
1162 /* We've followed the inferior through an exec. Therefore, the
1163 inferior has essentially been killed & reborn. */
1165 gdb_flush (gdb_stdout
);
1167 breakpoint_init_inferior (inf_execd
);
1169 exec_file_host
= exec_file_find (exec_file_target
, NULL
);
1170 old_chain
= make_cleanup (xfree
, exec_file_host
);
1172 /* If we were unable to map the executable target pathname onto a host
1173 pathname, tell the user that. Otherwise GDB's subsequent behavior
1174 is confusing. Maybe it would even be better to stop at this point
1175 so that the user can specify a file manually before continuing. */
1176 if (exec_file_host
== NULL
)
1177 warning (_("Could not load symbols for executable %s.\n"
1178 "Do you need \"set sysroot\"?"),
1181 /* Reset the shared library package. This ensures that we get a
1182 shlib event when the child reaches "_start", at which point the
1183 dld will have had a chance to initialize the child. */
1184 /* Also, loading a symbol file below may trigger symbol lookups, and
1185 we don't want those to be satisfied by the libraries of the
1186 previous incarnation of this process. */
1187 no_shared_libraries (NULL
, 0);
1189 if (follow_exec_mode_string
== follow_exec_mode_new
)
1191 /* The user wants to keep the old inferior and program spaces
1192 around. Create a new fresh one, and switch to it. */
1194 /* Do exit processing for the original inferior before adding
1195 the new inferior so we don't have two active inferiors with
1196 the same ptid, which can confuse find_inferior_ptid. */
1197 exit_inferior_num_silent (current_inferior ()->num
);
1199 inf
= add_inferior_with_spaces ();
1201 target_follow_exec (inf
, exec_file_target
);
1203 set_current_inferior (inf
);
1204 set_current_program_space (inf
->pspace
);
1209 /* The old description may no longer be fit for the new image.
1210 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1211 old description; we'll read a new one below. No need to do
1212 this on "follow-exec-mode new", as the old inferior stays
1213 around (its description is later cleared/refetched on
1215 target_clear_description ();
1218 gdb_assert (current_program_space
== inf
->pspace
);
1220 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1221 because the proper displacement for a PIE (Position Independent
1222 Executable) main symbol file will only be computed by
1223 solib_create_inferior_hook below. breakpoint_re_set would fail
1224 to insert the breakpoints with the zero displacement. */
1225 try_open_exec_file (exec_file_host
, inf
, SYMFILE_DEFER_BP_RESET
);
1227 do_cleanups (old_chain
);
1229 /* If the target can specify a description, read it. Must do this
1230 after flipping to the new executable (because the target supplied
1231 description must be compatible with the executable's
1232 architecture, and the old executable may e.g., be 32-bit, while
1233 the new one 64-bit), and before anything involving memory or
1235 target_find_description ();
1237 solib_create_inferior_hook (0);
1239 jit_inferior_created_hook ();
1241 breakpoint_re_set ();
1243 /* Reinsert all breakpoints. (Those which were symbolic have
1244 been reset to the proper address in the new a.out, thanks
1245 to symbol_file_command...). */
1246 insert_breakpoints ();
1248 /* The next resume of this inferior should bring it to the shlib
1249 startup breakpoints. (If the user had also set bp's on
1250 "main" from the old (parent) process, then they'll auto-
1251 matically get reset there in the new process.). */
1254 /* The queue of threads that need to do a step-over operation to get
1255 past e.g., a breakpoint. What technique is used to step over the
1256 breakpoint/watchpoint does not matter -- all threads end up in the
1257 same queue, to maintain rough temporal order of execution, in order
1258 to avoid starvation, otherwise, we could e.g., find ourselves
1259 constantly stepping the same couple threads past their breakpoints
1260 over and over, if the single-step finish fast enough. */
1261 struct thread_info
*step_over_queue_head
;
1263 /* Bit flags indicating what the thread needs to step over. */
1265 enum step_over_what_flag
1267 /* Step over a breakpoint. */
1268 STEP_OVER_BREAKPOINT
= 1,
1270 /* Step past a non-continuable watchpoint, in order to let the
1271 instruction execute so we can evaluate the watchpoint
1273 STEP_OVER_WATCHPOINT
= 2
1275 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1277 /* Info about an instruction that is being stepped over. */
1279 struct step_over_info
1281 /* If we're stepping past a breakpoint, this is the address space
1282 and address of the instruction the breakpoint is set at. We'll
1283 skip inserting all breakpoints here. Valid iff ASPACE is
1285 struct address_space
*aspace
;
1288 /* The instruction being stepped over triggers a nonsteppable
1289 watchpoint. If true, we'll skip inserting watchpoints. */
1290 int nonsteppable_watchpoint_p
;
1292 /* The thread's global number. */
1296 /* The step-over info of the location that is being stepped over.
1298 Note that with async/breakpoint always-inserted mode, a user might
1299 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1300 being stepped over. As setting a new breakpoint inserts all
1301 breakpoints, we need to make sure the breakpoint being stepped over
1302 isn't inserted then. We do that by only clearing the step-over
1303 info when the step-over is actually finished (or aborted).
1305 Presently GDB can only step over one breakpoint at any given time.
1306 Given threads that can't run code in the same address space as the
1307 breakpoint's can't really miss the breakpoint, GDB could be taught
1308 to step-over at most one breakpoint per address space (so this info
1309 could move to the address space object if/when GDB is extended).
1310 The set of breakpoints being stepped over will normally be much
1311 smaller than the set of all breakpoints, so a flag in the
1312 breakpoint location structure would be wasteful. A separate list
1313 also saves complexity and run-time, as otherwise we'd have to go
1314 through all breakpoint locations clearing their flag whenever we
1315 start a new sequence. Similar considerations weigh against storing
1316 this info in the thread object. Plus, not all step overs actually
1317 have breakpoint locations -- e.g., stepping past a single-step
1318 breakpoint, or stepping to complete a non-continuable
1320 static struct step_over_info step_over_info
;
1322 /* Record the address of the breakpoint/instruction we're currently
1324 N.B. We record the aspace and address now, instead of say just the thread,
1325 because when we need the info later the thread may be running. */
1328 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1329 int nonsteppable_watchpoint_p
,
1332 step_over_info
.aspace
= aspace
;
1333 step_over_info
.address
= address
;
1334 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1335 step_over_info
.thread
= thread
;
1338 /* Called when we're not longer stepping over a breakpoint / an
1339 instruction, so all breakpoints are free to be (re)inserted. */
1342 clear_step_over_info (void)
1345 fprintf_unfiltered (gdb_stdlog
,
1346 "infrun: clear_step_over_info\n");
1347 step_over_info
.aspace
= NULL
;
1348 step_over_info
.address
= 0;
1349 step_over_info
.nonsteppable_watchpoint_p
= 0;
1350 step_over_info
.thread
= -1;
1356 stepping_past_instruction_at (struct address_space
*aspace
,
1359 return (step_over_info
.aspace
!= NULL
1360 && breakpoint_address_match (aspace
, address
,
1361 step_over_info
.aspace
,
1362 step_over_info
.address
));
1368 thread_is_stepping_over_breakpoint (int thread
)
1370 return (step_over_info
.thread
!= -1
1371 && thread
== step_over_info
.thread
);
1377 stepping_past_nonsteppable_watchpoint (void)
1379 return step_over_info
.nonsteppable_watchpoint_p
;
1382 /* Returns true if step-over info is valid. */
1385 step_over_info_valid_p (void)
1387 return (step_over_info
.aspace
!= NULL
1388 || stepping_past_nonsteppable_watchpoint ());
1392 /* Displaced stepping. */
1394 /* In non-stop debugging mode, we must take special care to manage
1395 breakpoints properly; in particular, the traditional strategy for
1396 stepping a thread past a breakpoint it has hit is unsuitable.
1397 'Displaced stepping' is a tactic for stepping one thread past a
1398 breakpoint it has hit while ensuring that other threads running
1399 concurrently will hit the breakpoint as they should.
1401 The traditional way to step a thread T off a breakpoint in a
1402 multi-threaded program in all-stop mode is as follows:
1404 a0) Initially, all threads are stopped, and breakpoints are not
1406 a1) We single-step T, leaving breakpoints uninserted.
1407 a2) We insert breakpoints, and resume all threads.
1409 In non-stop debugging, however, this strategy is unsuitable: we
1410 don't want to have to stop all threads in the system in order to
1411 continue or step T past a breakpoint. Instead, we use displaced
1414 n0) Initially, T is stopped, other threads are running, and
1415 breakpoints are inserted.
1416 n1) We copy the instruction "under" the breakpoint to a separate
1417 location, outside the main code stream, making any adjustments
1418 to the instruction, register, and memory state as directed by
1420 n2) We single-step T over the instruction at its new location.
1421 n3) We adjust the resulting register and memory state as directed
1422 by T's architecture. This includes resetting T's PC to point
1423 back into the main instruction stream.
1426 This approach depends on the following gdbarch methods:
1428 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1429 indicate where to copy the instruction, and how much space must
1430 be reserved there. We use these in step n1.
1432 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1433 address, and makes any necessary adjustments to the instruction,
1434 register contents, and memory. We use this in step n1.
1436 - gdbarch_displaced_step_fixup adjusts registers and memory after
1437 we have successfuly single-stepped the instruction, to yield the
1438 same effect the instruction would have had if we had executed it
1439 at its original address. We use this in step n3.
1441 - gdbarch_displaced_step_free_closure provides cleanup.
1443 The gdbarch_displaced_step_copy_insn and
1444 gdbarch_displaced_step_fixup functions must be written so that
1445 copying an instruction with gdbarch_displaced_step_copy_insn,
1446 single-stepping across the copied instruction, and then applying
1447 gdbarch_displaced_insn_fixup should have the same effects on the
1448 thread's memory and registers as stepping the instruction in place
1449 would have. Exactly which responsibilities fall to the copy and
1450 which fall to the fixup is up to the author of those functions.
1452 See the comments in gdbarch.sh for details.
1454 Note that displaced stepping and software single-step cannot
1455 currently be used in combination, although with some care I think
1456 they could be made to. Software single-step works by placing
1457 breakpoints on all possible subsequent instructions; if the
1458 displaced instruction is a PC-relative jump, those breakpoints
1459 could fall in very strange places --- on pages that aren't
1460 executable, or at addresses that are not proper instruction
1461 boundaries. (We do generally let other threads run while we wait
1462 to hit the software single-step breakpoint, and they might
1463 encounter such a corrupted instruction.) One way to work around
1464 this would be to have gdbarch_displaced_step_copy_insn fully
1465 simulate the effect of PC-relative instructions (and return NULL)
1466 on architectures that use software single-stepping.
1468 In non-stop mode, we can have independent and simultaneous step
1469 requests, so more than one thread may need to simultaneously step
1470 over a breakpoint. The current implementation assumes there is
1471 only one scratch space per process. In this case, we have to
1472 serialize access to the scratch space. If thread A wants to step
1473 over a breakpoint, but we are currently waiting for some other
1474 thread to complete a displaced step, we leave thread A stopped and
1475 place it in the displaced_step_request_queue. Whenever a displaced
1476 step finishes, we pick the next thread in the queue and start a new
1477 displaced step operation on it. See displaced_step_prepare and
1478 displaced_step_fixup for details. */
1480 /* Per-inferior displaced stepping state. */
1481 struct displaced_step_inferior_state
1483 /* Pointer to next in linked list. */
1484 struct displaced_step_inferior_state
*next
;
1486 /* The process this displaced step state refers to. */
1489 /* True if preparing a displaced step ever failed. If so, we won't
1490 try displaced stepping for this inferior again. */
1493 /* If this is not null_ptid, this is the thread carrying out a
1494 displaced single-step in process PID. This thread's state will
1495 require fixing up once it has completed its step. */
1498 /* The architecture the thread had when we stepped it. */
1499 struct gdbarch
*step_gdbarch
;
1501 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1502 for post-step cleanup. */
1503 struct displaced_step_closure
*step_closure
;
1505 /* The address of the original instruction, and the copy we
1507 CORE_ADDR step_original
, step_copy
;
1509 /* Saved contents of copy area. */
1510 gdb_byte
*step_saved_copy
;
1513 /* The list of states of processes involved in displaced stepping
1515 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1517 /* Get the displaced stepping state of process PID. */
1519 static struct displaced_step_inferior_state
*
1520 get_displaced_stepping_state (int pid
)
1522 struct displaced_step_inferior_state
*state
;
1524 for (state
= displaced_step_inferior_states
;
1526 state
= state
->next
)
1527 if (state
->pid
== pid
)
1533 /* Returns true if any inferior has a thread doing a displaced
1537 displaced_step_in_progress_any_inferior (void)
1539 struct displaced_step_inferior_state
*state
;
1541 for (state
= displaced_step_inferior_states
;
1543 state
= state
->next
)
1544 if (!ptid_equal (state
->step_ptid
, null_ptid
))
1550 /* Return true if thread represented by PTID is doing a displaced
1554 displaced_step_in_progress_thread (ptid_t ptid
)
1556 struct displaced_step_inferior_state
*displaced
;
1558 gdb_assert (!ptid_equal (ptid
, null_ptid
));
1560 displaced
= get_displaced_stepping_state (ptid_get_pid (ptid
));
1562 return (displaced
!= NULL
&& ptid_equal (displaced
->step_ptid
, ptid
));
1565 /* Return true if process PID has a thread doing a displaced step. */
1568 displaced_step_in_progress (int pid
)
1570 struct displaced_step_inferior_state
*displaced
;
1572 displaced
= get_displaced_stepping_state (pid
);
1573 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1579 /* Add a new displaced stepping state for process PID to the displaced
1580 stepping state list, or return a pointer to an already existing
1581 entry, if it already exists. Never returns NULL. */
1583 static struct displaced_step_inferior_state
*
1584 add_displaced_stepping_state (int pid
)
1586 struct displaced_step_inferior_state
*state
;
1588 for (state
= displaced_step_inferior_states
;
1590 state
= state
->next
)
1591 if (state
->pid
== pid
)
1594 state
= XCNEW (struct displaced_step_inferior_state
);
1596 state
->next
= displaced_step_inferior_states
;
1597 displaced_step_inferior_states
= state
;
1602 /* If inferior is in displaced stepping, and ADDR equals to starting address
1603 of copy area, return corresponding displaced_step_closure. Otherwise,
1606 struct displaced_step_closure
*
1607 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1609 struct displaced_step_inferior_state
*displaced
1610 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1612 /* If checking the mode of displaced instruction in copy area. */
1613 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1614 && (displaced
->step_copy
== addr
))
1615 return displaced
->step_closure
;
1620 /* Remove the displaced stepping state of process PID. */
1623 remove_displaced_stepping_state (int pid
)
1625 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1627 gdb_assert (pid
!= 0);
1629 it
= displaced_step_inferior_states
;
1630 prev_next_p
= &displaced_step_inferior_states
;
1635 *prev_next_p
= it
->next
;
1640 prev_next_p
= &it
->next
;
1646 infrun_inferior_exit (struct inferior
*inf
)
1648 remove_displaced_stepping_state (inf
->pid
);
1651 /* If ON, and the architecture supports it, GDB will use displaced
1652 stepping to step over breakpoints. If OFF, or if the architecture
1653 doesn't support it, GDB will instead use the traditional
1654 hold-and-step approach. If AUTO (which is the default), GDB will
1655 decide which technique to use to step over breakpoints depending on
1656 which of all-stop or non-stop mode is active --- displaced stepping
1657 in non-stop mode; hold-and-step in all-stop mode. */
1659 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1662 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1663 struct cmd_list_element
*c
,
1666 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1667 fprintf_filtered (file
,
1668 _("Debugger's willingness to use displaced stepping "
1669 "to step over breakpoints is %s (currently %s).\n"),
1670 value
, target_is_non_stop_p () ? "on" : "off");
1672 fprintf_filtered (file
,
1673 _("Debugger's willingness to use displaced stepping "
1674 "to step over breakpoints is %s.\n"), value
);
1677 /* Return non-zero if displaced stepping can/should be used to step
1678 over breakpoints of thread TP. */
1681 use_displaced_stepping (struct thread_info
*tp
)
1683 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
1684 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1685 struct displaced_step_inferior_state
*displaced_state
;
1687 displaced_state
= get_displaced_stepping_state (ptid_get_pid (tp
->ptid
));
1689 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1690 && target_is_non_stop_p ())
1691 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1692 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1693 && find_record_target () == NULL
1694 && (displaced_state
== NULL
1695 || !displaced_state
->failed_before
));
1698 /* Clean out any stray displaced stepping state. */
1700 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1702 /* Indicate that there is no cleanup pending. */
1703 displaced
->step_ptid
= null_ptid
;
1705 if (displaced
->step_closure
)
1707 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1708 displaced
->step_closure
);
1709 displaced
->step_closure
= NULL
;
1714 displaced_step_clear_cleanup (void *arg
)
1716 struct displaced_step_inferior_state
*state
1717 = (struct displaced_step_inferior_state
*) arg
;
1719 displaced_step_clear (state
);
1722 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1724 displaced_step_dump_bytes (struct ui_file
*file
,
1725 const gdb_byte
*buf
,
1730 for (i
= 0; i
< len
; i
++)
1731 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1732 fputs_unfiltered ("\n", file
);
1735 /* Prepare to single-step, using displaced stepping.
1737 Note that we cannot use displaced stepping when we have a signal to
1738 deliver. If we have a signal to deliver and an instruction to step
1739 over, then after the step, there will be no indication from the
1740 target whether the thread entered a signal handler or ignored the
1741 signal and stepped over the instruction successfully --- both cases
1742 result in a simple SIGTRAP. In the first case we mustn't do a
1743 fixup, and in the second case we must --- but we can't tell which.
1744 Comments in the code for 'random signals' in handle_inferior_event
1745 explain how we handle this case instead.
1747 Returns 1 if preparing was successful -- this thread is going to be
1748 stepped now; 0 if displaced stepping this thread got queued; or -1
1749 if this instruction can't be displaced stepped. */
1752 displaced_step_prepare_throw (ptid_t ptid
)
1754 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1755 struct thread_info
*tp
= find_thread_ptid (ptid
);
1756 struct regcache
*regcache
= get_thread_regcache (ptid
);
1757 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1758 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1759 CORE_ADDR original
, copy
;
1761 struct displaced_step_closure
*closure
;
1762 struct displaced_step_inferior_state
*displaced
;
1765 /* We should never reach this function if the architecture does not
1766 support displaced stepping. */
1767 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1769 /* Nor if the thread isn't meant to step over a breakpoint. */
1770 gdb_assert (tp
->control
.trap_expected
);
1772 /* Disable range stepping while executing in the scratch pad. We
1773 want a single-step even if executing the displaced instruction in
1774 the scratch buffer lands within the stepping range (e.g., a
1776 tp
->control
.may_range_step
= 0;
1778 /* We have to displaced step one thread at a time, as we only have
1779 access to a single scratch space per inferior. */
1781 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1783 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1785 /* Already waiting for a displaced step to finish. Defer this
1786 request and place in queue. */
1788 if (debug_displaced
)
1789 fprintf_unfiltered (gdb_stdlog
,
1790 "displaced: deferring step of %s\n",
1791 target_pid_to_str (ptid
));
1793 thread_step_over_chain_enqueue (tp
);
1798 if (debug_displaced
)
1799 fprintf_unfiltered (gdb_stdlog
,
1800 "displaced: stepping %s now\n",
1801 target_pid_to_str (ptid
));
1804 displaced_step_clear (displaced
);
1806 old_cleanups
= save_inferior_ptid ();
1807 inferior_ptid
= ptid
;
1809 original
= regcache_read_pc (regcache
);
1811 copy
= gdbarch_displaced_step_location (gdbarch
);
1812 len
= gdbarch_max_insn_length (gdbarch
);
1814 if (breakpoint_in_range_p (aspace
, copy
, len
))
1816 /* There's a breakpoint set in the scratch pad location range
1817 (which is usually around the entry point). We'd either
1818 install it before resuming, which would overwrite/corrupt the
1819 scratch pad, or if it was already inserted, this displaced
1820 step would overwrite it. The latter is OK in the sense that
1821 we already assume that no thread is going to execute the code
1822 in the scratch pad range (after initial startup) anyway, but
1823 the former is unacceptable. Simply punt and fallback to
1824 stepping over this breakpoint in-line. */
1825 if (debug_displaced
)
1827 fprintf_unfiltered (gdb_stdlog
,
1828 "displaced: breakpoint set in scratch pad. "
1829 "Stepping over breakpoint in-line instead.\n");
1832 do_cleanups (old_cleanups
);
1836 /* Save the original contents of the copy area. */
1837 displaced
->step_saved_copy
= (gdb_byte
*) xmalloc (len
);
1838 ignore_cleanups
= make_cleanup (free_current_contents
,
1839 &displaced
->step_saved_copy
);
1840 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1842 throw_error (MEMORY_ERROR
,
1843 _("Error accessing memory address %s (%s) for "
1844 "displaced-stepping scratch space."),
1845 paddress (gdbarch
, copy
), safe_strerror (status
));
1846 if (debug_displaced
)
1848 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1849 paddress (gdbarch
, copy
));
1850 displaced_step_dump_bytes (gdb_stdlog
,
1851 displaced
->step_saved_copy
,
1855 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1856 original
, copy
, regcache
);
1857 if (closure
== NULL
)
1859 /* The architecture doesn't know how or want to displaced step
1860 this instruction or instruction sequence. Fallback to
1861 stepping over the breakpoint in-line. */
1862 do_cleanups (old_cleanups
);
1866 /* Save the information we need to fix things up if the step
1868 displaced
->step_ptid
= ptid
;
1869 displaced
->step_gdbarch
= gdbarch
;
1870 displaced
->step_closure
= closure
;
1871 displaced
->step_original
= original
;
1872 displaced
->step_copy
= copy
;
1874 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1876 /* Resume execution at the copy. */
1877 regcache_write_pc (regcache
, copy
);
1879 discard_cleanups (ignore_cleanups
);
1881 do_cleanups (old_cleanups
);
1883 if (debug_displaced
)
1884 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1885 paddress (gdbarch
, copy
));
1890 /* Wrapper for displaced_step_prepare_throw that disabled further
1891 attempts at displaced stepping if we get a memory error. */
1894 displaced_step_prepare (ptid_t ptid
)
1900 prepared
= displaced_step_prepare_throw (ptid
);
1902 CATCH (ex
, RETURN_MASK_ERROR
)
1904 struct displaced_step_inferior_state
*displaced_state
;
1906 if (ex
.error
!= MEMORY_ERROR
1907 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1908 throw_exception (ex
);
1912 fprintf_unfiltered (gdb_stdlog
,
1913 "infrun: disabling displaced stepping: %s\n",
1917 /* Be verbose if "set displaced-stepping" is "on", silent if
1919 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1921 warning (_("disabling displaced stepping: %s"),
1925 /* Disable further displaced stepping attempts. */
1927 = get_displaced_stepping_state (ptid_get_pid (ptid
));
1928 displaced_state
->failed_before
= 1;
1936 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1937 const gdb_byte
*myaddr
, int len
)
1939 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1941 inferior_ptid
= ptid
;
1942 write_memory (memaddr
, myaddr
, len
);
1943 do_cleanups (ptid_cleanup
);
1946 /* Restore the contents of the copy area for thread PTID. */
1949 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1952 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1954 write_memory_ptid (ptid
, displaced
->step_copy
,
1955 displaced
->step_saved_copy
, len
);
1956 if (debug_displaced
)
1957 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1958 target_pid_to_str (ptid
),
1959 paddress (displaced
->step_gdbarch
,
1960 displaced
->step_copy
));
1963 /* If we displaced stepped an instruction successfully, adjust
1964 registers and memory to yield the same effect the instruction would
1965 have had if we had executed it at its original address, and return
1966 1. If the instruction didn't complete, relocate the PC and return
1967 -1. If the thread wasn't displaced stepping, return 0. */
1970 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1972 struct cleanup
*old_cleanups
;
1973 struct displaced_step_inferior_state
*displaced
1974 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1977 /* Was any thread of this process doing a displaced step? */
1978 if (displaced
== NULL
)
1981 /* Was this event for the pid we displaced? */
1982 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1983 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1986 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1988 displaced_step_restore (displaced
, displaced
->step_ptid
);
1990 /* Fixup may need to read memory/registers. Switch to the thread
1991 that we're fixing up. Also, target_stopped_by_watchpoint checks
1992 the current thread. */
1993 switch_to_thread (event_ptid
);
1995 /* Did the instruction complete successfully? */
1996 if (signal
== GDB_SIGNAL_TRAP
1997 && !(target_stopped_by_watchpoint ()
1998 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1999 || target_have_steppable_watchpoint
)))
2001 /* Fix up the resulting state. */
2002 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
2003 displaced
->step_closure
,
2004 displaced
->step_original
,
2005 displaced
->step_copy
,
2006 get_thread_regcache (displaced
->step_ptid
));
2011 /* Since the instruction didn't complete, all we can do is
2013 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
2014 CORE_ADDR pc
= regcache_read_pc (regcache
);
2016 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
2017 regcache_write_pc (regcache
, pc
);
2021 do_cleanups (old_cleanups
);
2023 displaced
->step_ptid
= null_ptid
;
2028 /* Data to be passed around while handling an event. This data is
2029 discarded between events. */
2030 struct execution_control_state
2033 /* The thread that got the event, if this was a thread event; NULL
2035 struct thread_info
*event_thread
;
2037 struct target_waitstatus ws
;
2038 int stop_func_filled_in
;
2039 CORE_ADDR stop_func_start
;
2040 CORE_ADDR stop_func_end
;
2041 const char *stop_func_name
;
2044 /* True if the event thread hit the single-step breakpoint of
2045 another thread. Thus the event doesn't cause a stop, the thread
2046 needs to be single-stepped past the single-step breakpoint before
2047 we can switch back to the original stepping thread. */
2048 int hit_singlestep_breakpoint
;
2051 /* Clear ECS and set it to point at TP. */
2054 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
2056 memset (ecs
, 0, sizeof (*ecs
));
2057 ecs
->event_thread
= tp
;
2058 ecs
->ptid
= tp
->ptid
;
2061 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
2062 static void prepare_to_wait (struct execution_control_state
*ecs
);
2063 static int keep_going_stepped_thread (struct thread_info
*tp
);
2064 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
2066 /* Are there any pending step-over requests? If so, run all we can
2067 now and return true. Otherwise, return false. */
2070 start_step_over (void)
2072 struct thread_info
*tp
, *next
;
2074 /* Don't start a new step-over if we already have an in-line
2075 step-over operation ongoing. */
2076 if (step_over_info_valid_p ())
2079 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
2081 struct execution_control_state ecss
;
2082 struct execution_control_state
*ecs
= &ecss
;
2083 step_over_what step_what
;
2084 int must_be_in_line
;
2086 next
= thread_step_over_chain_next (tp
);
2088 /* If this inferior already has a displaced step in process,
2089 don't start a new one. */
2090 if (displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2093 step_what
= thread_still_needs_step_over (tp
);
2094 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
2095 || ((step_what
& STEP_OVER_BREAKPOINT
)
2096 && !use_displaced_stepping (tp
)));
2098 /* We currently stop all threads of all processes to step-over
2099 in-line. If we need to start a new in-line step-over, let
2100 any pending displaced steps finish first. */
2101 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
2104 thread_step_over_chain_remove (tp
);
2106 if (step_over_queue_head
== NULL
)
2109 fprintf_unfiltered (gdb_stdlog
,
2110 "infrun: step-over queue now empty\n");
2113 if (tp
->control
.trap_expected
2117 internal_error (__FILE__
, __LINE__
,
2118 "[%s] has inconsistent state: "
2119 "trap_expected=%d, resumed=%d, executing=%d\n",
2120 target_pid_to_str (tp
->ptid
),
2121 tp
->control
.trap_expected
,
2127 fprintf_unfiltered (gdb_stdlog
,
2128 "infrun: resuming [%s] for step-over\n",
2129 target_pid_to_str (tp
->ptid
));
2131 /* keep_going_pass_signal skips the step-over if the breakpoint
2132 is no longer inserted. In all-stop, we want to keep looking
2133 for a thread that needs a step-over instead of resuming TP,
2134 because we wouldn't be able to resume anything else until the
2135 target stops again. In non-stop, the resume always resumes
2136 only TP, so it's OK to let the thread resume freely. */
2137 if (!target_is_non_stop_p () && !step_what
)
2140 switch_to_thread (tp
->ptid
);
2141 reset_ecs (ecs
, tp
);
2142 keep_going_pass_signal (ecs
);
2144 if (!ecs
->wait_some_more
)
2145 error (_("Command aborted."));
2147 gdb_assert (tp
->resumed
);
2149 /* If we started a new in-line step-over, we're done. */
2150 if (step_over_info_valid_p ())
2152 gdb_assert (tp
->control
.trap_expected
);
2156 if (!target_is_non_stop_p ())
2158 /* On all-stop, shouldn't have resumed unless we needed a
2160 gdb_assert (tp
->control
.trap_expected
2161 || tp
->step_after_step_resume_breakpoint
);
2163 /* With remote targets (at least), in all-stop, we can't
2164 issue any further remote commands until the program stops
2169 /* Either the thread no longer needed a step-over, or a new
2170 displaced stepping sequence started. Even in the latter
2171 case, continue looking. Maybe we can also start another
2172 displaced step on a thread of other process. */
2178 /* Update global variables holding ptids to hold NEW_PTID if they were
2179 holding OLD_PTID. */
2181 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2183 struct displaced_step_inferior_state
*displaced
;
2185 if (ptid_equal (inferior_ptid
, old_ptid
))
2186 inferior_ptid
= new_ptid
;
2188 for (displaced
= displaced_step_inferior_states
;
2190 displaced
= displaced
->next
)
2192 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
2193 displaced
->step_ptid
= new_ptid
;
2200 /* Things to clean up if we QUIT out of resume (). */
2202 resume_cleanups (void *ignore
)
2204 if (!ptid_equal (inferior_ptid
, null_ptid
))
2205 delete_single_step_breakpoints (inferior_thread ());
2210 static const char schedlock_off
[] = "off";
2211 static const char schedlock_on
[] = "on";
2212 static const char schedlock_step
[] = "step";
2213 static const char schedlock_replay
[] = "replay";
2214 static const char *const scheduler_enums
[] = {
2221 static const char *scheduler_mode
= schedlock_replay
;
2223 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2224 struct cmd_list_element
*c
, const char *value
)
2226 fprintf_filtered (file
,
2227 _("Mode for locking scheduler "
2228 "during execution is \"%s\".\n"),
2233 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
2235 if (!target_can_lock_scheduler
)
2237 scheduler_mode
= schedlock_off
;
2238 error (_("Target '%s' cannot support this command."), target_shortname
);
2242 /* True if execution commands resume all threads of all processes by
2243 default; otherwise, resume only threads of the current inferior
2245 int sched_multi
= 0;
2247 /* Try to setup for software single stepping over the specified location.
2248 Return 1 if target_resume() should use hardware single step.
2250 GDBARCH the current gdbarch.
2251 PC the location to step over. */
2254 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2258 if (execution_direction
== EXEC_FORWARD
2259 && gdbarch_software_single_step_p (gdbarch
))
2260 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2268 user_visible_resume_ptid (int step
)
2274 /* With non-stop mode on, threads are always handled
2276 resume_ptid
= inferior_ptid
;
2278 else if ((scheduler_mode
== schedlock_on
)
2279 || (scheduler_mode
== schedlock_step
&& step
))
2281 /* User-settable 'scheduler' mode requires solo thread
2283 resume_ptid
= inferior_ptid
;
2285 else if ((scheduler_mode
== schedlock_replay
)
2286 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2288 /* User-settable 'scheduler' mode requires solo thread resume in replay
2290 resume_ptid
= inferior_ptid
;
2292 else if (!sched_multi
&& target_supports_multi_process ())
2294 /* Resume all threads of the current process (and none of other
2296 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2300 /* Resume all threads of all processes. */
2301 resume_ptid
= RESUME_ALL
;
2307 /* Return a ptid representing the set of threads that we will resume,
2308 in the perspective of the target, assuming run control handling
2309 does not require leaving some threads stopped (e.g., stepping past
2310 breakpoint). USER_STEP indicates whether we're about to start the
2311 target for a stepping command. */
2314 internal_resume_ptid (int user_step
)
2316 /* In non-stop, we always control threads individually. Note that
2317 the target may always work in non-stop mode even with "set
2318 non-stop off", in which case user_visible_resume_ptid could
2319 return a wildcard ptid. */
2320 if (target_is_non_stop_p ())
2321 return inferior_ptid
;
2323 return user_visible_resume_ptid (user_step
);
2326 /* Wrapper for target_resume, that handles infrun-specific
2330 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2332 struct thread_info
*tp
= inferior_thread ();
2334 /* Install inferior's terminal modes. */
2335 target_terminal_inferior ();
2337 /* Avoid confusing the next resume, if the next stop/resume
2338 happens to apply to another thread. */
2339 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2341 /* Advise target which signals may be handled silently.
2343 If we have removed breakpoints because we are stepping over one
2344 in-line (in any thread), we need to receive all signals to avoid
2345 accidentally skipping a breakpoint during execution of a signal
2348 Likewise if we're displaced stepping, otherwise a trap for a
2349 breakpoint in a signal handler might be confused with the
2350 displaced step finishing. We don't make the displaced_step_fixup
2351 step distinguish the cases instead, because:
2353 - a backtrace while stopped in the signal handler would show the
2354 scratch pad as frame older than the signal handler, instead of
2355 the real mainline code.
2357 - when the thread is later resumed, the signal handler would
2358 return to the scratch pad area, which would no longer be
2360 if (step_over_info_valid_p ()
2361 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2362 target_pass_signals (0, NULL
);
2364 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2366 target_resume (resume_ptid
, step
, sig
);
2368 target_commit_resume ();
2371 /* Resume the inferior, but allow a QUIT. This is useful if the user
2372 wants to interrupt some lengthy single-stepping operation
2373 (for child processes, the SIGINT goes to the inferior, and so
2374 we get a SIGINT random_signal, but for remote debugging and perhaps
2375 other targets, that's not true).
2377 SIG is the signal to give the inferior (zero for none). */
2379 resume (enum gdb_signal sig
)
2381 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2382 struct regcache
*regcache
= get_current_regcache ();
2383 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2384 struct thread_info
*tp
= inferior_thread ();
2385 CORE_ADDR pc
= regcache_read_pc (regcache
);
2386 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2388 /* This represents the user's step vs continue request. When
2389 deciding whether "set scheduler-locking step" applies, it's the
2390 user's intention that counts. */
2391 const int user_step
= tp
->control
.stepping_command
;
2392 /* This represents what we'll actually request the target to do.
2393 This can decay from a step to a continue, if e.g., we need to
2394 implement single-stepping with breakpoints (software
2398 gdb_assert (!thread_is_in_step_over_chain (tp
));
2402 if (tp
->suspend
.waitstatus_pending_p
)
2408 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2409 fprintf_unfiltered (gdb_stdlog
,
2410 "infrun: resume: thread %s has pending wait status %s "
2411 "(currently_stepping=%d).\n",
2412 target_pid_to_str (tp
->ptid
), statstr
,
2413 currently_stepping (tp
));
2419 /* FIXME: What should we do if we are supposed to resume this
2420 thread with a signal? Maybe we should maintain a queue of
2421 pending signals to deliver. */
2422 if (sig
!= GDB_SIGNAL_0
)
2424 warning (_("Couldn't deliver signal %s to %s."),
2425 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2428 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2429 discard_cleanups (old_cleanups
);
2431 if (target_can_async_p ())
2436 tp
->stepped_breakpoint
= 0;
2438 /* Depends on stepped_breakpoint. */
2439 step
= currently_stepping (tp
);
2441 if (current_inferior ()->waiting_for_vfork_done
)
2443 /* Don't try to single-step a vfork parent that is waiting for
2444 the child to get out of the shared memory region (by exec'ing
2445 or exiting). This is particularly important on software
2446 single-step archs, as the child process would trip on the
2447 software single step breakpoint inserted for the parent
2448 process. Since the parent will not actually execute any
2449 instruction until the child is out of the shared region (such
2450 are vfork's semantics), it is safe to simply continue it.
2451 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2452 the parent, and tell it to `keep_going', which automatically
2453 re-sets it stepping. */
2455 fprintf_unfiltered (gdb_stdlog
,
2456 "infrun: resume : clear step\n");
2461 fprintf_unfiltered (gdb_stdlog
,
2462 "infrun: resume (step=%d, signal=%s), "
2463 "trap_expected=%d, current thread [%s] at %s\n",
2464 step
, gdb_signal_to_symbol_string (sig
),
2465 tp
->control
.trap_expected
,
2466 target_pid_to_str (inferior_ptid
),
2467 paddress (gdbarch
, pc
));
2469 /* Normally, by the time we reach `resume', the breakpoints are either
2470 removed or inserted, as appropriate. The exception is if we're sitting
2471 at a permanent breakpoint; we need to step over it, but permanent
2472 breakpoints can't be removed. So we have to test for it here. */
2473 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2475 if (sig
!= GDB_SIGNAL_0
)
2477 /* We have a signal to pass to the inferior. The resume
2478 may, or may not take us to the signal handler. If this
2479 is a step, we'll need to stop in the signal handler, if
2480 there's one, (if the target supports stepping into
2481 handlers), or in the next mainline instruction, if
2482 there's no handler. If this is a continue, we need to be
2483 sure to run the handler with all breakpoints inserted.
2484 In all cases, set a breakpoint at the current address
2485 (where the handler returns to), and once that breakpoint
2486 is hit, resume skipping the permanent breakpoint. If
2487 that breakpoint isn't hit, then we've stepped into the
2488 signal handler (or hit some other event). We'll delete
2489 the step-resume breakpoint then. */
2492 fprintf_unfiltered (gdb_stdlog
,
2493 "infrun: resume: skipping permanent breakpoint, "
2494 "deliver signal first\n");
2496 clear_step_over_info ();
2497 tp
->control
.trap_expected
= 0;
2499 if (tp
->control
.step_resume_breakpoint
== NULL
)
2501 /* Set a "high-priority" step-resume, as we don't want
2502 user breakpoints at PC to trigger (again) when this
2504 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2505 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2507 tp
->step_after_step_resume_breakpoint
= step
;
2510 insert_breakpoints ();
2514 /* There's no signal to pass, we can go ahead and skip the
2515 permanent breakpoint manually. */
2517 fprintf_unfiltered (gdb_stdlog
,
2518 "infrun: resume: skipping permanent breakpoint\n");
2519 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2520 /* Update pc to reflect the new address from which we will
2521 execute instructions. */
2522 pc
= regcache_read_pc (regcache
);
2526 /* We've already advanced the PC, so the stepping part
2527 is done. Now we need to arrange for a trap to be
2528 reported to handle_inferior_event. Set a breakpoint
2529 at the current PC, and run to it. Don't update
2530 prev_pc, because if we end in
2531 switch_back_to_stepped_thread, we want the "expected
2532 thread advanced also" branch to be taken. IOW, we
2533 don't want this thread to step further from PC
2535 gdb_assert (!step_over_info_valid_p ());
2536 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2537 insert_breakpoints ();
2539 resume_ptid
= internal_resume_ptid (user_step
);
2540 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2541 discard_cleanups (old_cleanups
);
2548 /* If we have a breakpoint to step over, make sure to do a single
2549 step only. Same if we have software watchpoints. */
2550 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2551 tp
->control
.may_range_step
= 0;
2553 /* If enabled, step over breakpoints by executing a copy of the
2554 instruction at a different address.
2556 We can't use displaced stepping when we have a signal to deliver;
2557 the comments for displaced_step_prepare explain why. The
2558 comments in the handle_inferior event for dealing with 'random
2559 signals' explain what we do instead.
2561 We can't use displaced stepping when we are waiting for vfork_done
2562 event, displaced stepping breaks the vfork child similarly as single
2563 step software breakpoint. */
2564 if (tp
->control
.trap_expected
2565 && use_displaced_stepping (tp
)
2566 && !step_over_info_valid_p ()
2567 && sig
== GDB_SIGNAL_0
2568 && !current_inferior ()->waiting_for_vfork_done
)
2570 int prepared
= displaced_step_prepare (inferior_ptid
);
2575 fprintf_unfiltered (gdb_stdlog
,
2576 "Got placed in step-over queue\n");
2578 tp
->control
.trap_expected
= 0;
2579 discard_cleanups (old_cleanups
);
2582 else if (prepared
< 0)
2584 /* Fallback to stepping over the breakpoint in-line. */
2586 if (target_is_non_stop_p ())
2587 stop_all_threads ();
2589 set_step_over_info (get_regcache_aspace (regcache
),
2590 regcache_read_pc (regcache
), 0, tp
->global_num
);
2592 step
= maybe_software_singlestep (gdbarch
, pc
);
2594 insert_breakpoints ();
2596 else if (prepared
> 0)
2598 struct displaced_step_inferior_state
*displaced
;
2600 /* Update pc to reflect the new address from which we will
2601 execute instructions due to displaced stepping. */
2602 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2604 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2605 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2606 displaced
->step_closure
);
2610 /* Do we need to do it the hard way, w/temp breakpoints? */
2612 step
= maybe_software_singlestep (gdbarch
, pc
);
2614 /* Currently, our software single-step implementation leads to different
2615 results than hardware single-stepping in one situation: when stepping
2616 into delivering a signal which has an associated signal handler,
2617 hardware single-step will stop at the first instruction of the handler,
2618 while software single-step will simply skip execution of the handler.
2620 For now, this difference in behavior is accepted since there is no
2621 easy way to actually implement single-stepping into a signal handler
2622 without kernel support.
2624 However, there is one scenario where this difference leads to follow-on
2625 problems: if we're stepping off a breakpoint by removing all breakpoints
2626 and then single-stepping. In this case, the software single-step
2627 behavior means that even if there is a *breakpoint* in the signal
2628 handler, GDB still would not stop.
2630 Fortunately, we can at least fix this particular issue. We detect
2631 here the case where we are about to deliver a signal while software
2632 single-stepping with breakpoints removed. In this situation, we
2633 revert the decisions to remove all breakpoints and insert single-
2634 step breakpoints, and instead we install a step-resume breakpoint
2635 at the current address, deliver the signal without stepping, and
2636 once we arrive back at the step-resume breakpoint, actually step
2637 over the breakpoint we originally wanted to step over. */
2638 if (thread_has_single_step_breakpoints_set (tp
)
2639 && sig
!= GDB_SIGNAL_0
2640 && step_over_info_valid_p ())
2642 /* If we have nested signals or a pending signal is delivered
2643 immediately after a handler returns, might might already have
2644 a step-resume breakpoint set on the earlier handler. We cannot
2645 set another step-resume breakpoint; just continue on until the
2646 original breakpoint is hit. */
2647 if (tp
->control
.step_resume_breakpoint
== NULL
)
2649 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2650 tp
->step_after_step_resume_breakpoint
= 1;
2653 delete_single_step_breakpoints (tp
);
2655 clear_step_over_info ();
2656 tp
->control
.trap_expected
= 0;
2658 insert_breakpoints ();
2661 /* If STEP is set, it's a request to use hardware stepping
2662 facilities. But in that case, we should never
2663 use singlestep breakpoint. */
2664 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2666 /* Decide the set of threads to ask the target to resume. */
2667 if (tp
->control
.trap_expected
)
2669 /* We're allowing a thread to run past a breakpoint it has
2670 hit, either by single-stepping the thread with the breakpoint
2671 removed, or by displaced stepping, with the breakpoint inserted.
2672 In the former case, we need to single-step only this thread,
2673 and keep others stopped, as they can miss this breakpoint if
2674 allowed to run. That's not really a problem for displaced
2675 stepping, but, we still keep other threads stopped, in case
2676 another thread is also stopped for a breakpoint waiting for
2677 its turn in the displaced stepping queue. */
2678 resume_ptid
= inferior_ptid
;
2681 resume_ptid
= internal_resume_ptid (user_step
);
2683 if (execution_direction
!= EXEC_REVERSE
2684 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2686 /* There are two cases where we currently need to step a
2687 breakpoint instruction when we have a signal to deliver:
2689 - See handle_signal_stop where we handle random signals that
2690 could take out us out of the stepping range. Normally, in
2691 that case we end up continuing (instead of stepping) over the
2692 signal handler with a breakpoint at PC, but there are cases
2693 where we should _always_ single-step, even if we have a
2694 step-resume breakpoint, like when a software watchpoint is
2695 set. Assuming single-stepping and delivering a signal at the
2696 same time would takes us to the signal handler, then we could
2697 have removed the breakpoint at PC to step over it. However,
2698 some hardware step targets (like e.g., Mac OS) can't step
2699 into signal handlers, and for those, we need to leave the
2700 breakpoint at PC inserted, as otherwise if the handler
2701 recurses and executes PC again, it'll miss the breakpoint.
2702 So we leave the breakpoint inserted anyway, but we need to
2703 record that we tried to step a breakpoint instruction, so
2704 that adjust_pc_after_break doesn't end up confused.
2706 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2707 in one thread after another thread that was stepping had been
2708 momentarily paused for a step-over. When we re-resume the
2709 stepping thread, it may be resumed from that address with a
2710 breakpoint that hasn't trapped yet. Seen with
2711 gdb.threads/non-stop-fair-events.exp, on targets that don't
2712 do displaced stepping. */
2715 fprintf_unfiltered (gdb_stdlog
,
2716 "infrun: resume: [%s] stepped breakpoint\n",
2717 target_pid_to_str (tp
->ptid
));
2719 tp
->stepped_breakpoint
= 1;
2721 /* Most targets can step a breakpoint instruction, thus
2722 executing it normally. But if this one cannot, just
2723 continue and we will hit it anyway. */
2724 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2729 && tp
->control
.trap_expected
2730 && use_displaced_stepping (tp
)
2731 && !step_over_info_valid_p ())
2733 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2734 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2735 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2738 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2739 paddress (resume_gdbarch
, actual_pc
));
2740 read_memory (actual_pc
, buf
, sizeof (buf
));
2741 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2744 if (tp
->control
.may_range_step
)
2746 /* If we're resuming a thread with the PC out of the step
2747 range, then we're doing some nested/finer run control
2748 operation, like stepping the thread out of the dynamic
2749 linker or the displaced stepping scratch pad. We
2750 shouldn't have allowed a range step then. */
2751 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2754 do_target_resume (resume_ptid
, step
, sig
);
2756 discard_cleanups (old_cleanups
);
2763 /* Counter that tracks number of user visible stops. This can be used
2764 to tell whether a command has proceeded the inferior past the
2765 current location. This allows e.g., inferior function calls in
2766 breakpoint commands to not interrupt the command list. When the
2767 call finishes successfully, the inferior is standing at the same
2768 breakpoint as if nothing happened (and so we don't call
2770 static ULONGEST current_stop_id
;
2777 return current_stop_id
;
2780 /* Called when we report a user visible stop. */
2788 /* Clear out all variables saying what to do when inferior is continued.
2789 First do this, then set the ones you want, then call `proceed'. */
2792 clear_proceed_status_thread (struct thread_info
*tp
)
2795 fprintf_unfiltered (gdb_stdlog
,
2796 "infrun: clear_proceed_status_thread (%s)\n",
2797 target_pid_to_str (tp
->ptid
));
2799 /* If we're starting a new sequence, then the previous finished
2800 single-step is no longer relevant. */
2801 if (tp
->suspend
.waitstatus_pending_p
)
2803 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2806 fprintf_unfiltered (gdb_stdlog
,
2807 "infrun: clear_proceed_status: pending "
2808 "event of %s was a finished step. "
2810 target_pid_to_str (tp
->ptid
));
2812 tp
->suspend
.waitstatus_pending_p
= 0;
2813 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2815 else if (debug_infrun
)
2819 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2820 fprintf_unfiltered (gdb_stdlog
,
2821 "infrun: clear_proceed_status_thread: thread %s "
2822 "has pending wait status %s "
2823 "(currently_stepping=%d).\n",
2824 target_pid_to_str (tp
->ptid
), statstr
,
2825 currently_stepping (tp
));
2830 /* If this signal should not be seen by program, give it zero.
2831 Used for debugging signals. */
2832 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2833 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2835 thread_fsm_delete (tp
->thread_fsm
);
2836 tp
->thread_fsm
= NULL
;
2838 tp
->control
.trap_expected
= 0;
2839 tp
->control
.step_range_start
= 0;
2840 tp
->control
.step_range_end
= 0;
2841 tp
->control
.may_range_step
= 0;
2842 tp
->control
.step_frame_id
= null_frame_id
;
2843 tp
->control
.step_stack_frame_id
= null_frame_id
;
2844 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2845 tp
->control
.step_start_function
= NULL
;
2846 tp
->stop_requested
= 0;
2848 tp
->control
.stop_step
= 0;
2850 tp
->control
.proceed_to_finish
= 0;
2852 tp
->control
.stepping_command
= 0;
2854 /* Discard any remaining commands or status from previous stop. */
2855 bpstat_clear (&tp
->control
.stop_bpstat
);
2859 clear_proceed_status (int step
)
2861 /* With scheduler-locking replay, stop replaying other threads if we're
2862 not replaying the user-visible resume ptid.
2864 This is a convenience feature to not require the user to explicitly
2865 stop replaying the other threads. We're assuming that the user's
2866 intent is to resume tracing the recorded process. */
2867 if (!non_stop
&& scheduler_mode
== schedlock_replay
2868 && target_record_is_replaying (minus_one_ptid
)
2869 && !target_record_will_replay (user_visible_resume_ptid (step
),
2870 execution_direction
))
2871 target_record_stop_replaying ();
2875 struct thread_info
*tp
;
2878 resume_ptid
= user_visible_resume_ptid (step
);
2880 /* In all-stop mode, delete the per-thread status of all threads
2881 we're about to resume, implicitly and explicitly. */
2882 ALL_NON_EXITED_THREADS (tp
)
2884 if (!ptid_match (tp
->ptid
, resume_ptid
))
2886 clear_proceed_status_thread (tp
);
2890 if (!ptid_equal (inferior_ptid
, null_ptid
))
2892 struct inferior
*inferior
;
2896 /* If in non-stop mode, only delete the per-thread status of
2897 the current thread. */
2898 clear_proceed_status_thread (inferior_thread ());
2901 inferior
= current_inferior ();
2902 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2905 observer_notify_about_to_proceed ();
2908 /* Returns true if TP is still stopped at a breakpoint that needs
2909 stepping-over in order to make progress. If the breakpoint is gone
2910 meanwhile, we can skip the whole step-over dance. */
2913 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2915 if (tp
->stepping_over_breakpoint
)
2917 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2919 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2920 regcache_read_pc (regcache
))
2921 == ordinary_breakpoint_here
)
2924 tp
->stepping_over_breakpoint
= 0;
2930 /* Check whether thread TP still needs to start a step-over in order
2931 to make progress when resumed. Returns an bitwise or of enum
2932 step_over_what bits, indicating what needs to be stepped over. */
2934 static step_over_what
2935 thread_still_needs_step_over (struct thread_info
*tp
)
2937 step_over_what what
= 0;
2939 if (thread_still_needs_step_over_bp (tp
))
2940 what
|= STEP_OVER_BREAKPOINT
;
2942 if (tp
->stepping_over_watchpoint
2943 && !target_have_steppable_watchpoint
)
2944 what
|= STEP_OVER_WATCHPOINT
;
2949 /* Returns true if scheduler locking applies. STEP indicates whether
2950 we're about to do a step/next-like command to a thread. */
2953 schedlock_applies (struct thread_info
*tp
)
2955 return (scheduler_mode
== schedlock_on
2956 || (scheduler_mode
== schedlock_step
2957 && tp
->control
.stepping_command
)
2958 || (scheduler_mode
== schedlock_replay
2959 && target_record_will_replay (minus_one_ptid
,
2960 execution_direction
)));
2963 /* Basic routine for continuing the program in various fashions.
2965 ADDR is the address to resume at, or -1 for resume where stopped.
2966 SIGGNAL is the signal to give it, or 0 for none,
2967 or -1 for act according to how it stopped.
2968 STEP is nonzero if should trap after one instruction.
2969 -1 means return after that and print nothing.
2970 You should probably set various step_... variables
2971 before calling here, if you are stepping.
2973 You should call clear_proceed_status before calling proceed. */
2976 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2978 struct regcache
*regcache
;
2979 struct gdbarch
*gdbarch
;
2980 struct thread_info
*tp
;
2982 struct address_space
*aspace
;
2984 struct execution_control_state ecss
;
2985 struct execution_control_state
*ecs
= &ecss
;
2986 struct cleanup
*old_chain
;
2987 struct cleanup
*defer_resume_cleanup
;
2990 /* If we're stopped at a fork/vfork, follow the branch set by the
2991 "set follow-fork-mode" command; otherwise, we'll just proceed
2992 resuming the current thread. */
2993 if (!follow_fork ())
2995 /* The target for some reason decided not to resume. */
2997 if (target_can_async_p ())
2998 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3002 /* We'll update this if & when we switch to a new thread. */
3003 previous_inferior_ptid
= inferior_ptid
;
3005 regcache
= get_current_regcache ();
3006 gdbarch
= get_regcache_arch (regcache
);
3007 aspace
= get_regcache_aspace (regcache
);
3008 pc
= regcache_read_pc (regcache
);
3009 tp
= inferior_thread ();
3011 /* Fill in with reasonable starting values. */
3012 init_thread_stepping_state (tp
);
3014 gdb_assert (!thread_is_in_step_over_chain (tp
));
3016 if (addr
== (CORE_ADDR
) -1)
3019 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3020 && execution_direction
!= EXEC_REVERSE
)
3021 /* There is a breakpoint at the address we will resume at,
3022 step one instruction before inserting breakpoints so that
3023 we do not stop right away (and report a second hit at this
3026 Note, we don't do this in reverse, because we won't
3027 actually be executing the breakpoint insn anyway.
3028 We'll be (un-)executing the previous instruction. */
3029 tp
->stepping_over_breakpoint
= 1;
3030 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3031 && gdbarch_single_step_through_delay (gdbarch
,
3032 get_current_frame ()))
3033 /* We stepped onto an instruction that needs to be stepped
3034 again before re-inserting the breakpoint, do so. */
3035 tp
->stepping_over_breakpoint
= 1;
3039 regcache_write_pc (regcache
, addr
);
3042 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3043 tp
->suspend
.stop_signal
= siggnal
;
3045 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3047 /* If an exception is thrown from this point on, make sure to
3048 propagate GDB's knowledge of the executing state to the
3049 frontend/user running state. */
3050 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3052 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3053 threads (e.g., we might need to set threads stepping over
3054 breakpoints first), from the user/frontend's point of view, all
3055 threads in RESUME_PTID are now running. Unless we're calling an
3056 inferior function, as in that case we pretend the inferior
3057 doesn't run at all. */
3058 if (!tp
->control
.in_infcall
)
3059 set_running (resume_ptid
, 1);
3062 fprintf_unfiltered (gdb_stdlog
,
3063 "infrun: proceed (addr=%s, signal=%s)\n",
3064 paddress (gdbarch
, addr
),
3065 gdb_signal_to_symbol_string (siggnal
));
3067 annotate_starting ();
3069 /* Make sure that output from GDB appears before output from the
3071 gdb_flush (gdb_stdout
);
3073 /* In a multi-threaded task we may select another thread and
3074 then continue or step.
3076 But if a thread that we're resuming had stopped at a breakpoint,
3077 it will immediately cause another breakpoint stop without any
3078 execution (i.e. it will report a breakpoint hit incorrectly). So
3079 we must step over it first.
3081 Look for threads other than the current (TP) that reported a
3082 breakpoint hit and haven't been resumed yet since. */
3084 /* If scheduler locking applies, we can avoid iterating over all
3086 if (!non_stop
&& !schedlock_applies (tp
))
3088 struct thread_info
*current
= tp
;
3090 ALL_NON_EXITED_THREADS (tp
)
3092 /* Ignore the current thread here. It's handled
3097 /* Ignore threads of processes we're not resuming. */
3098 if (!ptid_match (tp
->ptid
, resume_ptid
))
3101 if (!thread_still_needs_step_over (tp
))
3104 gdb_assert (!thread_is_in_step_over_chain (tp
));
3107 fprintf_unfiltered (gdb_stdlog
,
3108 "infrun: need to step-over [%s] first\n",
3109 target_pid_to_str (tp
->ptid
));
3111 thread_step_over_chain_enqueue (tp
);
3117 /* Enqueue the current thread last, so that we move all other
3118 threads over their breakpoints first. */
3119 if (tp
->stepping_over_breakpoint
)
3120 thread_step_over_chain_enqueue (tp
);
3122 /* If the thread isn't started, we'll still need to set its prev_pc,
3123 so that switch_back_to_stepped_thread knows the thread hasn't
3124 advanced. Must do this before resuming any thread, as in
3125 all-stop/remote, once we resume we can't send any other packet
3126 until the target stops again. */
3127 tp
->prev_pc
= regcache_read_pc (regcache
);
3129 defer_resume_cleanup
= make_cleanup_defer_target_commit_resume ();
3131 started
= start_step_over ();
3133 if (step_over_info_valid_p ())
3135 /* Either this thread started a new in-line step over, or some
3136 other thread was already doing one. In either case, don't
3137 resume anything else until the step-over is finished. */
3139 else if (started
&& !target_is_non_stop_p ())
3141 /* A new displaced stepping sequence was started. In all-stop,
3142 we can't talk to the target anymore until it next stops. */
3144 else if (!non_stop
&& target_is_non_stop_p ())
3146 /* In all-stop, but the target is always in non-stop mode.
3147 Start all other threads that are implicitly resumed too. */
3148 ALL_NON_EXITED_THREADS (tp
)
3150 /* Ignore threads of processes we're not resuming. */
3151 if (!ptid_match (tp
->ptid
, resume_ptid
))
3157 fprintf_unfiltered (gdb_stdlog
,
3158 "infrun: proceed: [%s] resumed\n",
3159 target_pid_to_str (tp
->ptid
));
3160 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3164 if (thread_is_in_step_over_chain (tp
))
3167 fprintf_unfiltered (gdb_stdlog
,
3168 "infrun: proceed: [%s] needs step-over\n",
3169 target_pid_to_str (tp
->ptid
));
3174 fprintf_unfiltered (gdb_stdlog
,
3175 "infrun: proceed: resuming %s\n",
3176 target_pid_to_str (tp
->ptid
));
3178 reset_ecs (ecs
, tp
);
3179 switch_to_thread (tp
->ptid
);
3180 keep_going_pass_signal (ecs
);
3181 if (!ecs
->wait_some_more
)
3182 error (_("Command aborted."));
3185 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3187 /* The thread wasn't started, and isn't queued, run it now. */
3188 reset_ecs (ecs
, tp
);
3189 switch_to_thread (tp
->ptid
);
3190 keep_going_pass_signal (ecs
);
3191 if (!ecs
->wait_some_more
)
3192 error (_("Command aborted."));
3195 do_cleanups (defer_resume_cleanup
);
3196 target_commit_resume ();
3198 discard_cleanups (old_chain
);
3200 /* Tell the event loop to wait for it to stop. If the target
3201 supports asynchronous execution, it'll do this from within
3203 if (!target_can_async_p ())
3204 mark_async_event_handler (infrun_async_inferior_event_token
);
3208 /* Start remote-debugging of a machine over a serial link. */
3211 start_remote (int from_tty
)
3213 struct inferior
*inferior
;
3215 inferior
= current_inferior ();
3216 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3218 /* Always go on waiting for the target, regardless of the mode. */
3219 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3220 indicate to wait_for_inferior that a target should timeout if
3221 nothing is returned (instead of just blocking). Because of this,
3222 targets expecting an immediate response need to, internally, set
3223 things up so that the target_wait() is forced to eventually
3225 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3226 differentiate to its caller what the state of the target is after
3227 the initial open has been performed. Here we're assuming that
3228 the target has stopped. It should be possible to eventually have
3229 target_open() return to the caller an indication that the target
3230 is currently running and GDB state should be set to the same as
3231 for an async run. */
3232 wait_for_inferior ();
3234 /* Now that the inferior has stopped, do any bookkeeping like
3235 loading shared libraries. We want to do this before normal_stop,
3236 so that the displayed frame is up to date. */
3237 post_create_inferior (¤t_target
, from_tty
);
3242 /* Initialize static vars when a new inferior begins. */
3245 init_wait_for_inferior (void)
3247 /* These are meaningless until the first time through wait_for_inferior. */
3249 breakpoint_init_inferior (inf_starting
);
3251 clear_proceed_status (0);
3253 target_last_wait_ptid
= minus_one_ptid
;
3255 previous_inferior_ptid
= inferior_ptid
;
3257 /* Discard any skipped inlined frames. */
3258 clear_inline_frame_state (minus_one_ptid
);
3263 static void handle_inferior_event (struct execution_control_state
*ecs
);
3265 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3266 struct execution_control_state
*ecs
);
3267 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3268 struct execution_control_state
*ecs
);
3269 static void handle_signal_stop (struct execution_control_state
*ecs
);
3270 static void check_exception_resume (struct execution_control_state
*,
3271 struct frame_info
*);
3273 static void end_stepping_range (struct execution_control_state
*ecs
);
3274 static void stop_waiting (struct execution_control_state
*ecs
);
3275 static void keep_going (struct execution_control_state
*ecs
);
3276 static void process_event_stop_test (struct execution_control_state
*ecs
);
3277 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3279 /* Callback for iterate over threads. If the thread is stopped, but
3280 the user/frontend doesn't know about that yet, go through
3281 normal_stop, as if the thread had just stopped now. ARG points at
3282 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
3283 ptid_is_pid(PTID) is true, applies to all threads of the process
3284 pointed at by PTID. Otherwise, apply only to the thread pointed by
3288 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
3290 ptid_t ptid
= * (ptid_t
*) arg
;
3292 if ((ptid_equal (info
->ptid
, ptid
)
3293 || ptid_equal (minus_one_ptid
, ptid
)
3294 || (ptid_is_pid (ptid
)
3295 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
3296 && is_running (info
->ptid
)
3297 && !is_executing (info
->ptid
))
3299 struct cleanup
*old_chain
;
3300 struct execution_control_state ecss
;
3301 struct execution_control_state
*ecs
= &ecss
;
3303 memset (ecs
, 0, sizeof (*ecs
));
3305 old_chain
= make_cleanup_restore_current_thread ();
3307 overlay_cache_invalid
= 1;
3308 /* Flush target cache before starting to handle each event.
3309 Target was running and cache could be stale. This is just a
3310 heuristic. Running threads may modify target memory, but we
3311 don't get any event. */
3312 target_dcache_invalidate ();
3314 /* Go through handle_inferior_event/normal_stop, so we always
3315 have consistent output as if the stop event had been
3317 ecs
->ptid
= info
->ptid
;
3318 ecs
->event_thread
= info
;
3319 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
3320 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
3322 handle_inferior_event (ecs
);
3324 if (!ecs
->wait_some_more
)
3326 /* Cancel any running execution command. */
3327 thread_cancel_execution_command (info
);
3332 do_cleanups (old_chain
);
3338 /* This function is attached as a "thread_stop_requested" observer.
3339 Cleanup local state that assumed the PTID was to be resumed, and
3340 report the stop to the frontend. */
3343 infrun_thread_stop_requested (ptid_t ptid
)
3345 struct thread_info
*tp
;
3347 /* PTID was requested to stop. Remove matching threads from the
3348 step-over queue, so we don't try to resume them
3350 ALL_NON_EXITED_THREADS (tp
)
3351 if (ptid_match (tp
->ptid
, ptid
))
3353 if (thread_is_in_step_over_chain (tp
))
3354 thread_step_over_chain_remove (tp
);
3357 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
3361 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3363 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3364 nullify_last_target_wait_ptid ();
3367 /* Delete the step resume, single-step and longjmp/exception resume
3368 breakpoints of TP. */
3371 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3373 delete_step_resume_breakpoint (tp
);
3374 delete_exception_resume_breakpoint (tp
);
3375 delete_single_step_breakpoints (tp
);
3378 /* If the target still has execution, call FUNC for each thread that
3379 just stopped. In all-stop, that's all the non-exited threads; in
3380 non-stop, that's the current thread, only. */
3382 typedef void (*for_each_just_stopped_thread_callback_func
)
3383 (struct thread_info
*tp
);
3386 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3388 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3391 if (target_is_non_stop_p ())
3393 /* If in non-stop mode, only the current thread stopped. */
3394 func (inferior_thread ());
3398 struct thread_info
*tp
;
3400 /* In all-stop mode, all threads have stopped. */
3401 ALL_NON_EXITED_THREADS (tp
)
3408 /* Delete the step resume and longjmp/exception resume breakpoints of
3409 the threads that just stopped. */
3412 delete_just_stopped_threads_infrun_breakpoints (void)
3414 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3417 /* Delete the single-step breakpoints of the threads that just
3421 delete_just_stopped_threads_single_step_breakpoints (void)
3423 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3426 /* A cleanup wrapper. */
3429 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3431 delete_just_stopped_threads_infrun_breakpoints ();
3437 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3438 const struct target_waitstatus
*ws
)
3440 char *status_string
= target_waitstatus_to_string (ws
);
3443 /* The text is split over several lines because it was getting too long.
3444 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3445 output as a unit; we want only one timestamp printed if debug_timestamp
3448 stb
.printf ("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 stb
.printf (" [%s]", target_pid_to_str (waiton_ptid
));
3454 stb
.printf (", status) =\n");
3455 stb
.printf ("infrun: %d.%ld.%ld [%s],\n",
3456 ptid_get_pid (result_ptid
),
3457 ptid_get_lwp (result_ptid
),
3458 ptid_get_tid (result_ptid
),
3459 target_pid_to_str (result_ptid
));
3460 stb
.printf ("infrun: %s\n", status_string
);
3462 /* This uses %s in part to handle %'s in the text, but also to avoid
3463 a gcc error: the format attribute requires a string literal. */
3464 fprintf_unfiltered (gdb_stdlog
, "%s", stb
.c_str ());
3466 xfree (status_string
);
3469 /* Select a thread at random, out of those which are resumed and have
3472 static struct thread_info
*
3473 random_pending_event_thread (ptid_t waiton_ptid
)
3475 struct thread_info
*event_tp
;
3477 int random_selector
;
3479 /* First see how many events we have. Count only resumed threads
3480 that have an event pending. */
3481 ALL_NON_EXITED_THREADS (event_tp
)
3482 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3483 && event_tp
->resumed
3484 && event_tp
->suspend
.waitstatus_pending_p
)
3487 if (num_events
== 0)
3490 /* Now randomly pick a thread out of those that have had events. */
3491 random_selector
= (int)
3492 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3494 if (debug_infrun
&& num_events
> 1)
3495 fprintf_unfiltered (gdb_stdlog
,
3496 "infrun: Found %d events, selecting #%d\n",
3497 num_events
, random_selector
);
3499 /* Select the Nth thread that has had an event. */
3500 ALL_NON_EXITED_THREADS (event_tp
)
3501 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3502 && event_tp
->resumed
3503 && event_tp
->suspend
.waitstatus_pending_p
)
3504 if (random_selector
-- == 0)
3510 /* Wrapper for target_wait that first checks whether threads have
3511 pending statuses to report before actually asking the target for
3515 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3518 struct thread_info
*tp
;
3520 /* First check if there is a resumed thread with a wait status
3522 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3524 tp
= random_pending_event_thread (ptid
);
3529 fprintf_unfiltered (gdb_stdlog
,
3530 "infrun: Waiting for specific thread %s.\n",
3531 target_pid_to_str (ptid
));
3533 /* We have a specific thread to check. */
3534 tp
= find_thread_ptid (ptid
);
3535 gdb_assert (tp
!= NULL
);
3536 if (!tp
->suspend
.waitstatus_pending_p
)
3541 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3542 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3544 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3545 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3549 pc
= regcache_read_pc (regcache
);
3551 if (pc
!= tp
->suspend
.stop_pc
)
3554 fprintf_unfiltered (gdb_stdlog
,
3555 "infrun: PC of %s changed. was=%s, now=%s\n",
3556 target_pid_to_str (tp
->ptid
),
3557 paddress (gdbarch
, tp
->prev_pc
),
3558 paddress (gdbarch
, pc
));
3561 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3564 fprintf_unfiltered (gdb_stdlog
,
3565 "infrun: previous breakpoint of %s, at %s gone\n",
3566 target_pid_to_str (tp
->ptid
),
3567 paddress (gdbarch
, pc
));
3575 fprintf_unfiltered (gdb_stdlog
,
3576 "infrun: pending event of %s cancelled.\n",
3577 target_pid_to_str (tp
->ptid
));
3579 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3580 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3590 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3591 fprintf_unfiltered (gdb_stdlog
,
3592 "infrun: Using pending wait status %s for %s.\n",
3594 target_pid_to_str (tp
->ptid
));
3598 /* Now that we've selected our final event LWP, un-adjust its PC
3599 if it was a software breakpoint (and the target doesn't
3600 always adjust the PC itself). */
3601 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3602 && !target_supports_stopped_by_sw_breakpoint ())
3604 struct regcache
*regcache
;
3605 struct gdbarch
*gdbarch
;
3608 regcache
= get_thread_regcache (tp
->ptid
);
3609 gdbarch
= get_regcache_arch (regcache
);
3611 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3616 pc
= regcache_read_pc (regcache
);
3617 regcache_write_pc (regcache
, pc
+ decr_pc
);
3621 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3622 *status
= tp
->suspend
.waitstatus
;
3623 tp
->suspend
.waitstatus_pending_p
= 0;
3625 /* Wake up the event loop again, until all pending events are
3627 if (target_is_async_p ())
3628 mark_async_event_handler (infrun_async_inferior_event_token
);
3632 /* But if we don't find one, we'll have to wait. */
3634 if (deprecated_target_wait_hook
)
3635 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3637 event_ptid
= target_wait (ptid
, status
, options
);
3642 /* Prepare and stabilize the inferior for detaching it. E.g.,
3643 detaching while a thread is displaced stepping is a recipe for
3644 crashing it, as nothing would readjust the PC out of the scratch
3648 prepare_for_detach (void)
3650 struct inferior
*inf
= current_inferior ();
3651 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3652 struct cleanup
*old_chain_1
;
3653 struct displaced_step_inferior_state
*displaced
;
3655 displaced
= get_displaced_stepping_state (inf
->pid
);
3657 /* Is any thread of this process displaced stepping? If not,
3658 there's nothing else to do. */
3659 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3663 fprintf_unfiltered (gdb_stdlog
,
3664 "displaced-stepping in-process while detaching");
3666 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3669 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3671 struct cleanup
*old_chain_2
;
3672 struct execution_control_state ecss
;
3673 struct execution_control_state
*ecs
;
3676 memset (ecs
, 0, sizeof (*ecs
));
3678 overlay_cache_invalid
= 1;
3679 /* Flush target cache before starting to handle each event.
3680 Target was running and cache could be stale. This is just a
3681 heuristic. Running threads may modify target memory, but we
3682 don't get any event. */
3683 target_dcache_invalidate ();
3685 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3688 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3690 /* If an error happens while handling the event, propagate GDB's
3691 knowledge of the executing state to the frontend/user running
3693 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3696 /* Now figure out what to do with the result of the result. */
3697 handle_inferior_event (ecs
);
3699 /* No error, don't finish the state yet. */
3700 discard_cleanups (old_chain_2
);
3702 /* Breakpoints and watchpoints are not installed on the target
3703 at this point, and signals are passed directly to the
3704 inferior, so this must mean the process is gone. */
3705 if (!ecs
->wait_some_more
)
3707 discard_cleanups (old_chain_1
);
3708 error (_("Program exited while detaching"));
3712 discard_cleanups (old_chain_1
);
3715 /* Wait for control to return from inferior to debugger.
3717 If inferior gets a signal, we may decide to start it up again
3718 instead of returning. That is why there is a loop in this function.
3719 When this function actually returns it means the inferior
3720 should be left stopped and GDB should read more commands. */
3723 wait_for_inferior (void)
3725 struct cleanup
*old_cleanups
;
3726 struct cleanup
*thread_state_chain
;
3730 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3733 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3736 /* If an error happens while handling the event, propagate GDB's
3737 knowledge of the executing state to the frontend/user running
3739 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3743 struct execution_control_state ecss
;
3744 struct execution_control_state
*ecs
= &ecss
;
3745 ptid_t waiton_ptid
= minus_one_ptid
;
3747 memset (ecs
, 0, sizeof (*ecs
));
3749 overlay_cache_invalid
= 1;
3751 /* Flush target cache before starting to handle each event.
3752 Target was running and cache could be stale. This is just a
3753 heuristic. Running threads may modify target memory, but we
3754 don't get any event. */
3755 target_dcache_invalidate ();
3757 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3760 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3762 /* Now figure out what to do with the result of the result. */
3763 handle_inferior_event (ecs
);
3765 if (!ecs
->wait_some_more
)
3769 /* No error, don't finish the state yet. */
3770 discard_cleanups (thread_state_chain
);
3772 do_cleanups (old_cleanups
);
3775 /* Cleanup that reinstalls the readline callback handler, if the
3776 target is running in the background. If while handling the target
3777 event something triggered a secondary prompt, like e.g., a
3778 pagination prompt, we'll have removed the callback handler (see
3779 gdb_readline_wrapper_line). Need to do this as we go back to the
3780 event loop, ready to process further input. Note this has no
3781 effect if the handler hasn't actually been removed, because calling
3782 rl_callback_handler_install resets the line buffer, thus losing
3786 reinstall_readline_callback_handler_cleanup (void *arg
)
3788 struct ui
*ui
= current_ui
;
3792 /* We're not going back to the top level event loop yet. Don't
3793 install the readline callback, as it'd prep the terminal,
3794 readline-style (raw, noecho) (e.g., --batch). We'll install
3795 it the next time the prompt is displayed, when we're ready
3800 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3801 gdb_rl_callback_handler_reinstall ();
3804 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3805 that's just the event thread. In all-stop, that's all threads. */
3808 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3810 struct thread_info
*thr
= ecs
->event_thread
;
3812 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3813 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3817 ALL_NON_EXITED_THREADS (thr
)
3819 if (thr
->thread_fsm
== NULL
)
3821 if (thr
== ecs
->event_thread
)
3824 switch_to_thread (thr
->ptid
);
3825 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3828 if (ecs
->event_thread
!= NULL
)
3829 switch_to_thread (ecs
->event_thread
->ptid
);
3833 /* Helper for all_uis_check_sync_execution_done that works on the
3837 check_curr_ui_sync_execution_done (void)
3839 struct ui
*ui
= current_ui
;
3841 if (ui
->prompt_state
== PROMPT_NEEDED
3843 && !gdb_in_secondary_prompt_p (ui
))
3845 target_terminal_ours ();
3846 observer_notify_sync_execution_done ();
3847 ui_register_input_event_handler (ui
);
3854 all_uis_check_sync_execution_done (void)
3856 SWITCH_THRU_ALL_UIS ()
3858 check_curr_ui_sync_execution_done ();
3865 all_uis_on_sync_execution_starting (void)
3867 SWITCH_THRU_ALL_UIS ()
3869 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3870 async_disable_stdin ();
3874 /* Asynchronous version of wait_for_inferior. It is called by the
3875 event loop whenever a change of state is detected on the file
3876 descriptor corresponding to the target. It can be called more than
3877 once to complete a single execution command. In such cases we need
3878 to keep the state in a global variable ECSS. If it is the last time
3879 that this function is called for a single execution command, then
3880 report to the user that the inferior has stopped, and do the
3881 necessary cleanups. */
3884 fetch_inferior_event (void *client_data
)
3886 struct execution_control_state ecss
;
3887 struct execution_control_state
*ecs
= &ecss
;
3888 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3889 struct cleanup
*ts_old_chain
;
3891 ptid_t waiton_ptid
= minus_one_ptid
;
3893 memset (ecs
, 0, sizeof (*ecs
));
3895 /* Events are always processed with the main UI as current UI. This
3896 way, warnings, debug output, etc. are always consistently sent to
3897 the main console. */
3898 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3900 /* End up with readline processing input, if necessary. */
3901 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3903 /* We're handling a live event, so make sure we're doing live
3904 debugging. If we're looking at traceframes while the target is
3905 running, we're going to need to get back to that mode after
3906 handling the event. */
3909 make_cleanup_restore_current_traceframe ();
3910 set_current_traceframe (-1);
3914 /* In non-stop mode, the user/frontend should not notice a thread
3915 switch due to internal events. Make sure we reverse to the
3916 user selected thread and frame after handling the event and
3917 running any breakpoint commands. */
3918 make_cleanup_restore_current_thread ();
3920 overlay_cache_invalid
= 1;
3921 /* Flush target cache before starting to handle each event. Target
3922 was running and cache could be stale. This is just a heuristic.
3923 Running threads may modify target memory, but we don't get any
3925 target_dcache_invalidate ();
3927 scoped_restore save_exec_dir
3928 = make_scoped_restore (&execution_direction
, target_execution_direction ());
3930 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3931 target_can_async_p () ? TARGET_WNOHANG
: 0);
3934 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3936 /* If an error happens while handling the event, propagate GDB's
3937 knowledge of the executing state to the frontend/user running
3939 if (!target_is_non_stop_p ())
3940 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3942 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3944 /* Get executed before make_cleanup_restore_current_thread above to apply
3945 still for the thread which has thrown the exception. */
3946 make_bpstat_clear_actions_cleanup ();
3948 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3950 /* Now figure out what to do with the result of the result. */
3951 handle_inferior_event (ecs
);
3953 if (!ecs
->wait_some_more
)
3955 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3956 int should_stop
= 1;
3957 struct thread_info
*thr
= ecs
->event_thread
;
3958 int should_notify_stop
= 1;
3960 delete_just_stopped_threads_infrun_breakpoints ();
3964 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3966 if (thread_fsm
!= NULL
)
3967 should_stop
= thread_fsm_should_stop (thread_fsm
, thr
);
3976 clean_up_just_stopped_threads_fsms (ecs
);
3978 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3981 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
3984 if (should_notify_stop
)
3988 /* We may not find an inferior if this was a process exit. */
3989 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3990 proceeded
= normal_stop ();
3994 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
4001 /* No error, don't finish the thread states yet. */
4002 discard_cleanups (ts_old_chain
);
4004 /* Revert thread and frame. */
4005 do_cleanups (old_chain
);
4007 /* If a UI was in sync execution mode, and now isn't, restore its
4008 prompt (a synchronous execution command has finished, and we're
4009 ready for input). */
4010 all_uis_check_sync_execution_done ();
4013 && exec_done_display_p
4014 && (ptid_equal (inferior_ptid
, null_ptid
)
4015 || !is_running (inferior_ptid
)))
4016 printf_unfiltered (_("completed.\n"));
4019 /* Record the frame and location we're currently stepping through. */
4021 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
4023 struct thread_info
*tp
= inferior_thread ();
4025 tp
->control
.step_frame_id
= get_frame_id (frame
);
4026 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4028 tp
->current_symtab
= sal
.symtab
;
4029 tp
->current_line
= sal
.line
;
4032 /* Clear context switchable stepping state. */
4035 init_thread_stepping_state (struct thread_info
*tss
)
4037 tss
->stepped_breakpoint
= 0;
4038 tss
->stepping_over_breakpoint
= 0;
4039 tss
->stepping_over_watchpoint
= 0;
4040 tss
->step_after_step_resume_breakpoint
= 0;
4043 /* Set the cached copy of the last ptid/waitstatus. */
4046 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
4048 target_last_wait_ptid
= ptid
;
4049 target_last_waitstatus
= status
;
4052 /* Return the cached copy of the last pid/waitstatus returned by
4053 target_wait()/deprecated_target_wait_hook(). The data is actually
4054 cached by handle_inferior_event(), which gets called immediately
4055 after target_wait()/deprecated_target_wait_hook(). */
4058 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
4060 *ptidp
= target_last_wait_ptid
;
4061 *status
= target_last_waitstatus
;
4065 nullify_last_target_wait_ptid (void)
4067 target_last_wait_ptid
= minus_one_ptid
;
4070 /* Switch thread contexts. */
4073 context_switch (ptid_t ptid
)
4075 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4077 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4078 target_pid_to_str (inferior_ptid
));
4079 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4080 target_pid_to_str (ptid
));
4083 switch_to_thread (ptid
);
4086 /* If the target can't tell whether we've hit breakpoints
4087 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4088 check whether that could have been caused by a breakpoint. If so,
4089 adjust the PC, per gdbarch_decr_pc_after_break. */
4092 adjust_pc_after_break (struct thread_info
*thread
,
4093 struct target_waitstatus
*ws
)
4095 struct regcache
*regcache
;
4096 struct gdbarch
*gdbarch
;
4097 struct address_space
*aspace
;
4098 CORE_ADDR breakpoint_pc
, decr_pc
;
4100 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4101 we aren't, just return.
4103 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4104 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4105 implemented by software breakpoints should be handled through the normal
4108 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4109 different signals (SIGILL or SIGEMT for instance), but it is less
4110 clear where the PC is pointing afterwards. It may not match
4111 gdbarch_decr_pc_after_break. I don't know any specific target that
4112 generates these signals at breakpoints (the code has been in GDB since at
4113 least 1992) so I can not guess how to handle them here.
4115 In earlier versions of GDB, a target with
4116 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4117 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4118 target with both of these set in GDB history, and it seems unlikely to be
4119 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4121 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4124 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4127 /* In reverse execution, when a breakpoint is hit, the instruction
4128 under it has already been de-executed. The reported PC always
4129 points at the breakpoint address, so adjusting it further would
4130 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4133 B1 0x08000000 : INSN1
4134 B2 0x08000001 : INSN2
4136 PC -> 0x08000003 : INSN4
4138 Say you're stopped at 0x08000003 as above. Reverse continuing
4139 from that point should hit B2 as below. Reading the PC when the
4140 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4141 been de-executed already.
4143 B1 0x08000000 : INSN1
4144 B2 PC -> 0x08000001 : INSN2
4148 We can't apply the same logic as for forward execution, because
4149 we would wrongly adjust the PC to 0x08000000, since there's a
4150 breakpoint at PC - 1. We'd then report a hit on B1, although
4151 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4153 if (execution_direction
== EXEC_REVERSE
)
4156 /* If the target can tell whether the thread hit a SW breakpoint,
4157 trust it. Targets that can tell also adjust the PC
4159 if (target_supports_stopped_by_sw_breakpoint ())
4162 /* Note that relying on whether a breakpoint is planted in memory to
4163 determine this can fail. E.g,. the breakpoint could have been
4164 removed since. Or the thread could have been told to step an
4165 instruction the size of a breakpoint instruction, and only
4166 _after_ was a breakpoint inserted at its address. */
4168 /* If this target does not decrement the PC after breakpoints, then
4169 we have nothing to do. */
4170 regcache
= get_thread_regcache (thread
->ptid
);
4171 gdbarch
= get_regcache_arch (regcache
);
4173 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4177 aspace
= get_regcache_aspace (regcache
);
4179 /* Find the location where (if we've hit a breakpoint) the
4180 breakpoint would be. */
4181 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4183 /* If the target can't tell whether a software breakpoint triggered,
4184 fallback to figuring it out based on breakpoints we think were
4185 inserted in the target, and on whether the thread was stepped or
4188 /* Check whether there actually is a software breakpoint inserted at
4191 If in non-stop mode, a race condition is possible where we've
4192 removed a breakpoint, but stop events for that breakpoint were
4193 already queued and arrive later. To suppress those spurious
4194 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4195 and retire them after a number of stop events are reported. Note
4196 this is an heuristic and can thus get confused. The real fix is
4197 to get the "stopped by SW BP and needs adjustment" info out of
4198 the target/kernel (and thus never reach here; see above). */
4199 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4200 || (target_is_non_stop_p ()
4201 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4203 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4205 if (record_full_is_used ())
4206 record_full_gdb_operation_disable_set ();
4208 /* When using hardware single-step, a SIGTRAP is reported for both
4209 a completed single-step and a software breakpoint. Need to
4210 differentiate between the two, as the latter needs adjusting
4211 but the former does not.
4213 The SIGTRAP can be due to a completed hardware single-step only if
4214 - we didn't insert software single-step breakpoints
4215 - this thread is currently being stepped
4217 If any of these events did not occur, we must have stopped due
4218 to hitting a software breakpoint, and have to back up to the
4221 As a special case, we could have hardware single-stepped a
4222 software breakpoint. In this case (prev_pc == breakpoint_pc),
4223 we also need to back up to the breakpoint address. */
4225 if (thread_has_single_step_breakpoints_set (thread
)
4226 || !currently_stepping (thread
)
4227 || (thread
->stepped_breakpoint
4228 && thread
->prev_pc
== breakpoint_pc
))
4229 regcache_write_pc (regcache
, breakpoint_pc
);
4231 do_cleanups (old_cleanups
);
4236 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4238 for (frame
= get_prev_frame (frame
);
4240 frame
= get_prev_frame (frame
))
4242 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4244 if (get_frame_type (frame
) != INLINE_FRAME
)
4251 /* Auxiliary function that handles syscall entry/return events.
4252 It returns 1 if the inferior should keep going (and GDB
4253 should ignore the event), or 0 if the event deserves to be
4257 handle_syscall_event (struct execution_control_state
*ecs
)
4259 struct regcache
*regcache
;
4262 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4263 context_switch (ecs
->ptid
);
4265 regcache
= get_thread_regcache (ecs
->ptid
);
4266 syscall_number
= ecs
->ws
.value
.syscall_number
;
4267 stop_pc
= regcache_read_pc (regcache
);
4269 if (catch_syscall_enabled () > 0
4270 && catching_syscall_number (syscall_number
) > 0)
4273 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4276 ecs
->event_thread
->control
.stop_bpstat
4277 = bpstat_stop_status (get_regcache_aspace (regcache
),
4278 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4280 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4282 /* Catchpoint hit. */
4287 /* If no catchpoint triggered for this, then keep going. */
4292 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4295 fill_in_stop_func (struct gdbarch
*gdbarch
,
4296 struct execution_control_state
*ecs
)
4298 if (!ecs
->stop_func_filled_in
)
4300 /* Don't care about return value; stop_func_start and stop_func_name
4301 will both be 0 if it doesn't work. */
4302 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4303 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4304 ecs
->stop_func_start
4305 += gdbarch_deprecated_function_start_offset (gdbarch
);
4307 if (gdbarch_skip_entrypoint_p (gdbarch
))
4308 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4309 ecs
->stop_func_start
);
4311 ecs
->stop_func_filled_in
= 1;
4316 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4318 static enum stop_kind
4319 get_inferior_stop_soon (ptid_t ptid
)
4321 struct inferior
*inf
= find_inferior_ptid (ptid
);
4323 gdb_assert (inf
!= NULL
);
4324 return inf
->control
.stop_soon
;
4327 /* Wait for one event. Store the resulting waitstatus in WS, and
4328 return the event ptid. */
4331 wait_one (struct target_waitstatus
*ws
)
4334 ptid_t wait_ptid
= minus_one_ptid
;
4336 overlay_cache_invalid
= 1;
4338 /* Flush target cache before starting to handle each event.
4339 Target was running and cache could be stale. This is just a
4340 heuristic. Running threads may modify target memory, but we
4341 don't get any event. */
4342 target_dcache_invalidate ();
4344 if (deprecated_target_wait_hook
)
4345 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4347 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4350 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4355 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4356 instead of the current thread. */
4357 #define THREAD_STOPPED_BY(REASON) \
4359 thread_stopped_by_ ## REASON (ptid_t ptid) \
4361 struct cleanup *old_chain; \
4364 old_chain = save_inferior_ptid (); \
4365 inferior_ptid = ptid; \
4367 res = target_stopped_by_ ## REASON (); \
4369 do_cleanups (old_chain); \
4374 /* Generate thread_stopped_by_watchpoint. */
4375 THREAD_STOPPED_BY (watchpoint
)
4376 /* Generate thread_stopped_by_sw_breakpoint. */
4377 THREAD_STOPPED_BY (sw_breakpoint
)
4378 /* Generate thread_stopped_by_hw_breakpoint. */
4379 THREAD_STOPPED_BY (hw_breakpoint
)
4381 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4384 switch_to_thread_cleanup (void *ptid_p
)
4386 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4388 switch_to_thread (ptid
);
4391 /* Save the thread's event and stop reason to process it later. */
4394 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4396 struct regcache
*regcache
;
4397 struct address_space
*aspace
;
4403 statstr
= target_waitstatus_to_string (ws
);
4404 fprintf_unfiltered (gdb_stdlog
,
4405 "infrun: saving status %s for %d.%ld.%ld\n",
4407 ptid_get_pid (tp
->ptid
),
4408 ptid_get_lwp (tp
->ptid
),
4409 ptid_get_tid (tp
->ptid
));
4413 /* Record for later. */
4414 tp
->suspend
.waitstatus
= *ws
;
4415 tp
->suspend
.waitstatus_pending_p
= 1;
4417 regcache
= get_thread_regcache (tp
->ptid
);
4418 aspace
= get_regcache_aspace (regcache
);
4420 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4421 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4423 CORE_ADDR pc
= regcache_read_pc (regcache
);
4425 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4427 if (thread_stopped_by_watchpoint (tp
->ptid
))
4429 tp
->suspend
.stop_reason
4430 = TARGET_STOPPED_BY_WATCHPOINT
;
4432 else if (target_supports_stopped_by_sw_breakpoint ()
4433 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4435 tp
->suspend
.stop_reason
4436 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4438 else if (target_supports_stopped_by_hw_breakpoint ()
4439 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4441 tp
->suspend
.stop_reason
4442 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4444 else if (!target_supports_stopped_by_hw_breakpoint ()
4445 && hardware_breakpoint_inserted_here_p (aspace
,
4448 tp
->suspend
.stop_reason
4449 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4451 else if (!target_supports_stopped_by_sw_breakpoint ()
4452 && software_breakpoint_inserted_here_p (aspace
,
4455 tp
->suspend
.stop_reason
4456 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4458 else if (!thread_has_single_step_breakpoints_set (tp
)
4459 && currently_stepping (tp
))
4461 tp
->suspend
.stop_reason
4462 = TARGET_STOPPED_BY_SINGLE_STEP
;
4467 /* A cleanup that disables thread create/exit events. */
4470 disable_thread_events (void *arg
)
4472 target_thread_events (0);
4478 stop_all_threads (void)
4480 /* We may need multiple passes to discover all threads. */
4484 struct cleanup
*old_chain
;
4486 gdb_assert (target_is_non_stop_p ());
4489 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4491 entry_ptid
= inferior_ptid
;
4492 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4494 target_thread_events (1);
4495 make_cleanup (disable_thread_events
, NULL
);
4497 /* Request threads to stop, and then wait for the stops. Because
4498 threads we already know about can spawn more threads while we're
4499 trying to stop them, and we only learn about new threads when we
4500 update the thread list, do this in a loop, and keep iterating
4501 until two passes find no threads that need to be stopped. */
4502 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4505 fprintf_unfiltered (gdb_stdlog
,
4506 "infrun: stop_all_threads, pass=%d, "
4507 "iterations=%d\n", pass
, iterations
);
4511 struct target_waitstatus ws
;
4513 struct thread_info
*t
;
4515 update_thread_list ();
4517 /* Go through all threads looking for threads that we need
4518 to tell the target to stop. */
4519 ALL_NON_EXITED_THREADS (t
)
4523 /* If already stopping, don't request a stop again.
4524 We just haven't seen the notification yet. */
4525 if (!t
->stop_requested
)
4528 fprintf_unfiltered (gdb_stdlog
,
4529 "infrun: %s executing, "
4531 target_pid_to_str (t
->ptid
));
4532 target_stop (t
->ptid
);
4533 t
->stop_requested
= 1;
4538 fprintf_unfiltered (gdb_stdlog
,
4539 "infrun: %s executing, "
4540 "already stopping\n",
4541 target_pid_to_str (t
->ptid
));
4544 if (t
->stop_requested
)
4550 fprintf_unfiltered (gdb_stdlog
,
4551 "infrun: %s not executing\n",
4552 target_pid_to_str (t
->ptid
));
4554 /* The thread may be not executing, but still be
4555 resumed with a pending status to process. */
4563 /* If we find new threads on the second iteration, restart
4564 over. We want to see two iterations in a row with all
4569 event_ptid
= wait_one (&ws
);
4570 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4572 /* All resumed threads exited. */
4574 else if (ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4575 || ws
.kind
== TARGET_WAITKIND_EXITED
4576 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4580 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4582 fprintf_unfiltered (gdb_stdlog
,
4583 "infrun: %s exited while "
4584 "stopping threads\n",
4585 target_pid_to_str (ptid
));
4590 struct inferior
*inf
;
4592 t
= find_thread_ptid (event_ptid
);
4594 t
= add_thread (event_ptid
);
4596 t
->stop_requested
= 0;
4599 t
->control
.may_range_step
= 0;
4601 /* This may be the first time we see the inferior report
4603 inf
= find_inferior_ptid (event_ptid
);
4604 if (inf
->needs_setup
)
4606 switch_to_thread_no_regs (t
);
4610 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4611 && ws
.value
.sig
== GDB_SIGNAL_0
)
4613 /* We caught the event that we intended to catch, so
4614 there's no event pending. */
4615 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4616 t
->suspend
.waitstatus_pending_p
= 0;
4618 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4620 /* Add it back to the step-over queue. */
4623 fprintf_unfiltered (gdb_stdlog
,
4624 "infrun: displaced-step of %s "
4625 "canceled: adding back to the "
4626 "step-over queue\n",
4627 target_pid_to_str (t
->ptid
));
4629 t
->control
.trap_expected
= 0;
4630 thread_step_over_chain_enqueue (t
);
4635 enum gdb_signal sig
;
4636 struct regcache
*regcache
;
4642 statstr
= target_waitstatus_to_string (&ws
);
4643 fprintf_unfiltered (gdb_stdlog
,
4644 "infrun: target_wait %s, saving "
4645 "status for %d.%ld.%ld\n",
4647 ptid_get_pid (t
->ptid
),
4648 ptid_get_lwp (t
->ptid
),
4649 ptid_get_tid (t
->ptid
));
4653 /* Record for later. */
4654 save_waitstatus (t
, &ws
);
4656 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4657 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4659 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4661 /* Add it back to the step-over queue. */
4662 t
->control
.trap_expected
= 0;
4663 thread_step_over_chain_enqueue (t
);
4666 regcache
= get_thread_regcache (t
->ptid
);
4667 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4671 fprintf_unfiltered (gdb_stdlog
,
4672 "infrun: saved stop_pc=%s for %s "
4673 "(currently_stepping=%d)\n",
4674 paddress (target_gdbarch (),
4675 t
->suspend
.stop_pc
),
4676 target_pid_to_str (t
->ptid
),
4677 currently_stepping (t
));
4684 do_cleanups (old_chain
);
4687 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4690 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4693 handle_no_resumed (struct execution_control_state
*ecs
)
4695 struct inferior
*inf
;
4696 struct thread_info
*thread
;
4698 if (target_can_async_p ())
4705 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4713 /* There were no unwaited-for children left in the target, but,
4714 we're not synchronously waiting for events either. Just
4718 fprintf_unfiltered (gdb_stdlog
,
4719 "infrun: TARGET_WAITKIND_NO_RESUMED "
4720 "(ignoring: bg)\n");
4721 prepare_to_wait (ecs
);
4726 /* Otherwise, if we were running a synchronous execution command, we
4727 may need to cancel it and give the user back the terminal.
4729 In non-stop mode, the target can't tell whether we've already
4730 consumed previous stop events, so it can end up sending us a
4731 no-resumed event like so:
4733 #0 - thread 1 is left stopped
4735 #1 - thread 2 is resumed and hits breakpoint
4736 -> TARGET_WAITKIND_STOPPED
4738 #2 - thread 3 is resumed and exits
4739 this is the last resumed thread, so
4740 -> TARGET_WAITKIND_NO_RESUMED
4742 #3 - gdb processes stop for thread 2 and decides to re-resume
4745 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4746 thread 2 is now resumed, so the event should be ignored.
4748 IOW, if the stop for thread 2 doesn't end a foreground command,
4749 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4750 event. But it could be that the event meant that thread 2 itself
4751 (or whatever other thread was the last resumed thread) exited.
4753 To address this we refresh the thread list and check whether we
4754 have resumed threads _now_. In the example above, this removes
4755 thread 3 from the thread list. If thread 2 was re-resumed, we
4756 ignore this event. If we find no thread resumed, then we cancel
4757 the synchronous command show "no unwaited-for " to the user. */
4758 update_thread_list ();
4760 ALL_NON_EXITED_THREADS (thread
)
4762 if (thread
->executing
4763 || thread
->suspend
.waitstatus_pending_p
)
4765 /* There were no unwaited-for children left in the target at
4766 some point, but there are now. Just ignore. */
4768 fprintf_unfiltered (gdb_stdlog
,
4769 "infrun: TARGET_WAITKIND_NO_RESUMED "
4770 "(ignoring: found resumed)\n");
4771 prepare_to_wait (ecs
);
4776 /* Note however that we may find no resumed thread because the whole
4777 process exited meanwhile (thus updating the thread list results
4778 in an empty thread list). In this case we know we'll be getting
4779 a process exit event shortly. */
4785 thread
= any_live_thread_of_process (inf
->pid
);
4789 fprintf_unfiltered (gdb_stdlog
,
4790 "infrun: TARGET_WAITKIND_NO_RESUMED "
4791 "(expect process exit)\n");
4792 prepare_to_wait (ecs
);
4797 /* Go ahead and report the event. */
4801 /* Given an execution control state that has been freshly filled in by
4802 an event from the inferior, figure out what it means and take
4805 The alternatives are:
4807 1) stop_waiting and return; to really stop and return to the
4810 2) keep_going and return; to wait for the next event (set
4811 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4815 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4817 enum stop_kind stop_soon
;
4819 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4821 /* We had an event in the inferior, but we are not interested in
4822 handling it at this level. The lower layers have already
4823 done what needs to be done, if anything.
4825 One of the possible circumstances for this is when the
4826 inferior produces output for the console. The inferior has
4827 not stopped, and we are ignoring the event. Another possible
4828 circumstance is any event which the lower level knows will be
4829 reported multiple times without an intervening resume. */
4831 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4832 prepare_to_wait (ecs
);
4836 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4839 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4840 prepare_to_wait (ecs
);
4844 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4845 && handle_no_resumed (ecs
))
4848 /* Cache the last pid/waitstatus. */
4849 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4851 /* Always clear state belonging to the previous time we stopped. */
4852 stop_stack_dummy
= STOP_NONE
;
4854 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4856 /* No unwaited-for children left. IOW, all resumed children
4859 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4861 stop_print_frame
= 0;
4866 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4867 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4869 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4870 /* If it's a new thread, add it to the thread database. */
4871 if (ecs
->event_thread
== NULL
)
4872 ecs
->event_thread
= add_thread (ecs
->ptid
);
4874 /* Disable range stepping. If the next step request could use a
4875 range, this will be end up re-enabled then. */
4876 ecs
->event_thread
->control
.may_range_step
= 0;
4879 /* Dependent on valid ECS->EVENT_THREAD. */
4880 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4882 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4883 reinit_frame_cache ();
4885 breakpoint_retire_moribund ();
4887 /* First, distinguish signals caused by the debugger from signals
4888 that have to do with the program's own actions. Note that
4889 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4890 on the operating system version. Here we detect when a SIGILL or
4891 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4892 something similar for SIGSEGV, since a SIGSEGV will be generated
4893 when we're trying to execute a breakpoint instruction on a
4894 non-executable stack. This happens for call dummy breakpoints
4895 for architectures like SPARC that place call dummies on the
4897 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4898 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4899 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4900 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4902 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4904 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4905 regcache_read_pc (regcache
)))
4908 fprintf_unfiltered (gdb_stdlog
,
4909 "infrun: Treating signal as SIGTRAP\n");
4910 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4914 /* Mark the non-executing threads accordingly. In all-stop, all
4915 threads of all processes are stopped when we get any event
4916 reported. In non-stop mode, only the event thread stops. */
4920 if (!target_is_non_stop_p ())
4921 mark_ptid
= minus_one_ptid
;
4922 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4923 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4925 /* If we're handling a process exit in non-stop mode, even
4926 though threads haven't been deleted yet, one would think
4927 that there is nothing to do, as threads of the dead process
4928 will be soon deleted, and threads of any other process were
4929 left running. However, on some targets, threads survive a
4930 process exit event. E.g., for the "checkpoint" command,
4931 when the current checkpoint/fork exits, linux-fork.c
4932 automatically switches to another fork from within
4933 target_mourn_inferior, by associating the same
4934 inferior/thread to another fork. We haven't mourned yet at
4935 this point, but we must mark any threads left in the
4936 process as not-executing so that finish_thread_state marks
4937 them stopped (in the user's perspective) if/when we present
4938 the stop to the user. */
4939 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4942 mark_ptid
= ecs
->ptid
;
4944 set_executing (mark_ptid
, 0);
4946 /* Likewise the resumed flag. */
4947 set_resumed (mark_ptid
, 0);
4950 switch (ecs
->ws
.kind
)
4952 case TARGET_WAITKIND_LOADED
:
4954 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4955 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4956 context_switch (ecs
->ptid
);
4957 /* Ignore gracefully during startup of the inferior, as it might
4958 be the shell which has just loaded some objects, otherwise
4959 add the symbols for the newly loaded objects. Also ignore at
4960 the beginning of an attach or remote session; we will query
4961 the full list of libraries once the connection is
4964 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4965 if (stop_soon
== NO_STOP_QUIETLY
)
4967 struct regcache
*regcache
;
4969 regcache
= get_thread_regcache (ecs
->ptid
);
4971 handle_solib_event ();
4973 ecs
->event_thread
->control
.stop_bpstat
4974 = bpstat_stop_status (get_regcache_aspace (regcache
),
4975 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4977 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4979 /* A catchpoint triggered. */
4980 process_event_stop_test (ecs
);
4984 /* If requested, stop when the dynamic linker notifies
4985 gdb of events. This allows the user to get control
4986 and place breakpoints in initializer routines for
4987 dynamically loaded objects (among other things). */
4988 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4989 if (stop_on_solib_events
)
4991 /* Make sure we print "Stopped due to solib-event" in
4993 stop_print_frame
= 1;
5000 /* If we are skipping through a shell, or through shared library
5001 loading that we aren't interested in, resume the program. If
5002 we're running the program normally, also resume. */
5003 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5005 /* Loading of shared libraries might have changed breakpoint
5006 addresses. Make sure new breakpoints are inserted. */
5007 if (stop_soon
== NO_STOP_QUIETLY
)
5008 insert_breakpoints ();
5009 resume (GDB_SIGNAL_0
);
5010 prepare_to_wait (ecs
);
5014 /* But stop if we're attaching or setting up a remote
5016 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5017 || stop_soon
== STOP_QUIETLY_REMOTE
)
5020 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5025 internal_error (__FILE__
, __LINE__
,
5026 _("unhandled stop_soon: %d"), (int) stop_soon
);
5028 case TARGET_WAITKIND_SPURIOUS
:
5030 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5031 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5032 context_switch (ecs
->ptid
);
5033 resume (GDB_SIGNAL_0
);
5034 prepare_to_wait (ecs
);
5037 case TARGET_WAITKIND_THREAD_CREATED
:
5039 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5040 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5041 context_switch (ecs
->ptid
);
5042 if (!switch_back_to_stepped_thread (ecs
))
5046 case TARGET_WAITKIND_EXITED
:
5047 case TARGET_WAITKIND_SIGNALLED
:
5050 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5051 fprintf_unfiltered (gdb_stdlog
,
5052 "infrun: TARGET_WAITKIND_EXITED\n");
5054 fprintf_unfiltered (gdb_stdlog
,
5055 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5058 inferior_ptid
= ecs
->ptid
;
5059 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
5060 set_current_program_space (current_inferior ()->pspace
);
5061 handle_vfork_child_exec_or_exit (0);
5062 target_terminal_ours (); /* Must do this before mourn anyway. */
5064 /* Clearing any previous state of convenience variables. */
5065 clear_exit_convenience_vars ();
5067 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5069 /* Record the exit code in the convenience variable $_exitcode, so
5070 that the user can inspect this again later. */
5071 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5072 (LONGEST
) ecs
->ws
.value
.integer
);
5074 /* Also record this in the inferior itself. */
5075 current_inferior ()->has_exit_code
= 1;
5076 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5078 /* Support the --return-child-result option. */
5079 return_child_result_value
= ecs
->ws
.value
.integer
;
5081 observer_notify_exited (ecs
->ws
.value
.integer
);
5085 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5086 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5088 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5090 /* Set the value of the internal variable $_exitsignal,
5091 which holds the signal uncaught by the inferior. */
5092 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5093 gdbarch_gdb_signal_to_target (gdbarch
,
5094 ecs
->ws
.value
.sig
));
5098 /* We don't have access to the target's method used for
5099 converting between signal numbers (GDB's internal
5100 representation <-> target's representation).
5101 Therefore, we cannot do a good job at displaying this
5102 information to the user. It's better to just warn
5103 her about it (if infrun debugging is enabled), and
5106 fprintf_filtered (gdb_stdlog
, _("\
5107 Cannot fill $_exitsignal with the correct signal number.\n"));
5110 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
5113 gdb_flush (gdb_stdout
);
5114 target_mourn_inferior (inferior_ptid
);
5115 stop_print_frame
= 0;
5119 /* The following are the only cases in which we keep going;
5120 the above cases end in a continue or goto. */
5121 case TARGET_WAITKIND_FORKED
:
5122 case TARGET_WAITKIND_VFORKED
:
5125 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5126 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
5128 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
5131 /* Check whether the inferior is displaced stepping. */
5133 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5134 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5136 /* If checking displaced stepping is supported, and thread
5137 ecs->ptid is displaced stepping. */
5138 if (displaced_step_in_progress_thread (ecs
->ptid
))
5140 struct inferior
*parent_inf
5141 = find_inferior_ptid (ecs
->ptid
);
5142 struct regcache
*child_regcache
;
5143 CORE_ADDR parent_pc
;
5145 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5146 indicating that the displaced stepping of syscall instruction
5147 has been done. Perform cleanup for parent process here. Note
5148 that this operation also cleans up the child process for vfork,
5149 because their pages are shared. */
5150 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
5151 /* Start a new step-over in another thread if there's one
5155 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5157 struct displaced_step_inferior_state
*displaced
5158 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
5160 /* Restore scratch pad for child process. */
5161 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
5164 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5165 the child's PC is also within the scratchpad. Set the child's PC
5166 to the parent's PC value, which has already been fixed up.
5167 FIXME: we use the parent's aspace here, although we're touching
5168 the child, because the child hasn't been added to the inferior
5169 list yet at this point. */
5172 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
5174 parent_inf
->aspace
);
5175 /* Read PC value of parent process. */
5176 parent_pc
= regcache_read_pc (regcache
);
5178 if (debug_displaced
)
5179 fprintf_unfiltered (gdb_stdlog
,
5180 "displaced: write child pc from %s to %s\n",
5182 regcache_read_pc (child_regcache
)),
5183 paddress (gdbarch
, parent_pc
));
5185 regcache_write_pc (child_regcache
, parent_pc
);
5189 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5190 context_switch (ecs
->ptid
);
5192 /* Immediately detach breakpoints from the child before there's
5193 any chance of letting the user delete breakpoints from the
5194 breakpoint lists. If we don't do this early, it's easy to
5195 leave left over traps in the child, vis: "break foo; catch
5196 fork; c; <fork>; del; c; <child calls foo>". We only follow
5197 the fork on the last `continue', and by that time the
5198 breakpoint at "foo" is long gone from the breakpoint table.
5199 If we vforked, then we don't need to unpatch here, since both
5200 parent and child are sharing the same memory pages; we'll
5201 need to unpatch at follow/detach time instead to be certain
5202 that new breakpoints added between catchpoint hit time and
5203 vfork follow are detached. */
5204 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5206 /* This won't actually modify the breakpoint list, but will
5207 physically remove the breakpoints from the child. */
5208 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5211 delete_just_stopped_threads_single_step_breakpoints ();
5213 /* In case the event is caught by a catchpoint, remember that
5214 the event is to be followed at the next resume of the thread,
5215 and not immediately. */
5216 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5218 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5220 ecs
->event_thread
->control
.stop_bpstat
5221 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5222 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5224 /* If no catchpoint triggered for this, then keep going. Note
5225 that we're interested in knowing the bpstat actually causes a
5226 stop, not just if it may explain the signal. Software
5227 watchpoints, for example, always appear in the bpstat. */
5228 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5234 = (follow_fork_mode_string
== follow_fork_mode_child
);
5236 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5238 should_resume
= follow_fork ();
5241 child
= ecs
->ws
.value
.related_pid
;
5243 /* At this point, the parent is marked running, and the
5244 child is marked stopped. */
5246 /* If not resuming the parent, mark it stopped. */
5247 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5248 set_running (parent
, 0);
5250 /* If resuming the child, mark it running. */
5251 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5252 set_running (child
, 1);
5254 /* In non-stop mode, also resume the other branch. */
5255 if (!detach_fork
&& (non_stop
5256 || (sched_multi
&& target_is_non_stop_p ())))
5259 switch_to_thread (parent
);
5261 switch_to_thread (child
);
5263 ecs
->event_thread
= inferior_thread ();
5264 ecs
->ptid
= inferior_ptid
;
5269 switch_to_thread (child
);
5271 switch_to_thread (parent
);
5273 ecs
->event_thread
= inferior_thread ();
5274 ecs
->ptid
= inferior_ptid
;
5282 process_event_stop_test (ecs
);
5285 case TARGET_WAITKIND_VFORK_DONE
:
5286 /* Done with the shared memory region. Re-insert breakpoints in
5287 the parent, and keep going. */
5290 fprintf_unfiltered (gdb_stdlog
,
5291 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5293 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5294 context_switch (ecs
->ptid
);
5296 current_inferior ()->waiting_for_vfork_done
= 0;
5297 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5298 /* This also takes care of reinserting breakpoints in the
5299 previously locked inferior. */
5303 case TARGET_WAITKIND_EXECD
:
5305 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5307 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5308 context_switch (ecs
->ptid
);
5310 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5312 /* Do whatever is necessary to the parent branch of the vfork. */
5313 handle_vfork_child_exec_or_exit (1);
5315 /* This causes the eventpoints and symbol table to be reset.
5316 Must do this now, before trying to determine whether to
5318 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5320 /* In follow_exec we may have deleted the original thread and
5321 created a new one. Make sure that the event thread is the
5322 execd thread for that case (this is a nop otherwise). */
5323 ecs
->event_thread
= inferior_thread ();
5325 ecs
->event_thread
->control
.stop_bpstat
5326 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5327 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5329 /* Note that this may be referenced from inside
5330 bpstat_stop_status above, through inferior_has_execd. */
5331 xfree (ecs
->ws
.value
.execd_pathname
);
5332 ecs
->ws
.value
.execd_pathname
= NULL
;
5334 /* If no catchpoint triggered for this, then keep going. */
5335 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5337 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5341 process_event_stop_test (ecs
);
5344 /* Be careful not to try to gather much state about a thread
5345 that's in a syscall. It's frequently a losing proposition. */
5346 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5348 fprintf_unfiltered (gdb_stdlog
,
5349 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5350 /* Getting the current syscall number. */
5351 if (handle_syscall_event (ecs
) == 0)
5352 process_event_stop_test (ecs
);
5355 /* Before examining the threads further, step this thread to
5356 get it entirely out of the syscall. (We get notice of the
5357 event when the thread is just on the verge of exiting a
5358 syscall. Stepping one instruction seems to get it back
5360 case TARGET_WAITKIND_SYSCALL_RETURN
:
5362 fprintf_unfiltered (gdb_stdlog
,
5363 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5364 if (handle_syscall_event (ecs
) == 0)
5365 process_event_stop_test (ecs
);
5368 case TARGET_WAITKIND_STOPPED
:
5370 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5371 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5372 handle_signal_stop (ecs
);
5375 case TARGET_WAITKIND_NO_HISTORY
:
5377 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5378 /* Reverse execution: target ran out of history info. */
5380 /* Switch to the stopped thread. */
5381 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5382 context_switch (ecs
->ptid
);
5384 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5386 delete_just_stopped_threads_single_step_breakpoints ();
5387 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5388 observer_notify_no_history ();
5394 /* A wrapper around handle_inferior_event_1, which also makes sure
5395 that all temporary struct value objects that were created during
5396 the handling of the event get deleted at the end. */
5399 handle_inferior_event (struct execution_control_state
*ecs
)
5401 struct value
*mark
= value_mark ();
5403 handle_inferior_event_1 (ecs
);
5404 /* Purge all temporary values created during the event handling,
5405 as it could be a long time before we return to the command level
5406 where such values would otherwise be purged. */
5407 value_free_to_mark (mark
);
5410 /* Restart threads back to what they were trying to do back when we
5411 paused them for an in-line step-over. The EVENT_THREAD thread is
5415 restart_threads (struct thread_info
*event_thread
)
5417 struct thread_info
*tp
;
5419 /* In case the instruction just stepped spawned a new thread. */
5420 update_thread_list ();
5422 ALL_NON_EXITED_THREADS (tp
)
5424 if (tp
== event_thread
)
5427 fprintf_unfiltered (gdb_stdlog
,
5428 "infrun: restart threads: "
5429 "[%s] is event thread\n",
5430 target_pid_to_str (tp
->ptid
));
5434 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5437 fprintf_unfiltered (gdb_stdlog
,
5438 "infrun: restart threads: "
5439 "[%s] not meant to be running\n",
5440 target_pid_to_str (tp
->ptid
));
5447 fprintf_unfiltered (gdb_stdlog
,
5448 "infrun: restart threads: [%s] resumed\n",
5449 target_pid_to_str (tp
->ptid
));
5450 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5454 if (thread_is_in_step_over_chain (tp
))
5457 fprintf_unfiltered (gdb_stdlog
,
5458 "infrun: restart threads: "
5459 "[%s] needs step-over\n",
5460 target_pid_to_str (tp
->ptid
));
5461 gdb_assert (!tp
->resumed
);
5466 if (tp
->suspend
.waitstatus_pending_p
)
5469 fprintf_unfiltered (gdb_stdlog
,
5470 "infrun: restart threads: "
5471 "[%s] has pending status\n",
5472 target_pid_to_str (tp
->ptid
));
5477 /* If some thread needs to start a step-over at this point, it
5478 should still be in the step-over queue, and thus skipped
5480 if (thread_still_needs_step_over (tp
))
5482 internal_error (__FILE__
, __LINE__
,
5483 "thread [%s] needs a step-over, but not in "
5484 "step-over queue\n",
5485 target_pid_to_str (tp
->ptid
));
5488 if (currently_stepping (tp
))
5491 fprintf_unfiltered (gdb_stdlog
,
5492 "infrun: restart threads: [%s] was stepping\n",
5493 target_pid_to_str (tp
->ptid
));
5494 keep_going_stepped_thread (tp
);
5498 struct execution_control_state ecss
;
5499 struct execution_control_state
*ecs
= &ecss
;
5502 fprintf_unfiltered (gdb_stdlog
,
5503 "infrun: restart threads: [%s] continuing\n",
5504 target_pid_to_str (tp
->ptid
));
5505 reset_ecs (ecs
, tp
);
5506 switch_to_thread (tp
->ptid
);
5507 keep_going_pass_signal (ecs
);
5512 /* Callback for iterate_over_threads. Find a resumed thread that has
5513 a pending waitstatus. */
5516 resumed_thread_with_pending_status (struct thread_info
*tp
,
5520 && tp
->suspend
.waitstatus_pending_p
);
5523 /* Called when we get an event that may finish an in-line or
5524 out-of-line (displaced stepping) step-over started previously.
5525 Return true if the event is processed and we should go back to the
5526 event loop; false if the caller should continue processing the
5530 finish_step_over (struct execution_control_state
*ecs
)
5532 int had_step_over_info
;
5534 displaced_step_fixup (ecs
->ptid
,
5535 ecs
->event_thread
->suspend
.stop_signal
);
5537 had_step_over_info
= step_over_info_valid_p ();
5539 if (had_step_over_info
)
5541 /* If we're stepping over a breakpoint with all threads locked,
5542 then only the thread that was stepped should be reporting
5544 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5546 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5547 clear_step_over_info ();
5550 if (!target_is_non_stop_p ())
5553 /* Start a new step-over in another thread if there's one that
5557 /* If we were stepping over a breakpoint before, and haven't started
5558 a new in-line step-over sequence, then restart all other threads
5559 (except the event thread). We can't do this in all-stop, as then
5560 e.g., we wouldn't be able to issue any other remote packet until
5561 these other threads stop. */
5562 if (had_step_over_info
&& !step_over_info_valid_p ())
5564 struct thread_info
*pending
;
5566 /* If we only have threads with pending statuses, the restart
5567 below won't restart any thread and so nothing re-inserts the
5568 breakpoint we just stepped over. But we need it inserted
5569 when we later process the pending events, otherwise if
5570 another thread has a pending event for this breakpoint too,
5571 we'd discard its event (because the breakpoint that
5572 originally caused the event was no longer inserted). */
5573 context_switch (ecs
->ptid
);
5574 insert_breakpoints ();
5576 restart_threads (ecs
->event_thread
);
5578 /* If we have events pending, go through handle_inferior_event
5579 again, picking up a pending event at random. This avoids
5580 thread starvation. */
5582 /* But not if we just stepped over a watchpoint in order to let
5583 the instruction execute so we can evaluate its expression.
5584 The set of watchpoints that triggered is recorded in the
5585 breakpoint objects themselves (see bp->watchpoint_triggered).
5586 If we processed another event first, that other event could
5587 clobber this info. */
5588 if (ecs
->event_thread
->stepping_over_watchpoint
)
5591 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5593 if (pending
!= NULL
)
5595 struct thread_info
*tp
= ecs
->event_thread
;
5596 struct regcache
*regcache
;
5600 fprintf_unfiltered (gdb_stdlog
,
5601 "infrun: found resumed threads with "
5602 "pending events, saving status\n");
5605 gdb_assert (pending
!= tp
);
5607 /* Record the event thread's event for later. */
5608 save_waitstatus (tp
, &ecs
->ws
);
5609 /* This was cleared early, by handle_inferior_event. Set it
5610 so this pending event is considered by
5614 gdb_assert (!tp
->executing
);
5616 regcache
= get_thread_regcache (tp
->ptid
);
5617 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5621 fprintf_unfiltered (gdb_stdlog
,
5622 "infrun: saved stop_pc=%s for %s "
5623 "(currently_stepping=%d)\n",
5624 paddress (target_gdbarch (),
5625 tp
->suspend
.stop_pc
),
5626 target_pid_to_str (tp
->ptid
),
5627 currently_stepping (tp
));
5630 /* This in-line step-over finished; clear this so we won't
5631 start a new one. This is what handle_signal_stop would
5632 do, if we returned false. */
5633 tp
->stepping_over_breakpoint
= 0;
5635 /* Wake up the event loop again. */
5636 mark_async_event_handler (infrun_async_inferior_event_token
);
5638 prepare_to_wait (ecs
);
5646 /* Come here when the program has stopped with a signal. */
5649 handle_signal_stop (struct execution_control_state
*ecs
)
5651 struct frame_info
*frame
;
5652 struct gdbarch
*gdbarch
;
5653 int stopped_by_watchpoint
;
5654 enum stop_kind stop_soon
;
5657 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5659 /* Do we need to clean up the state of a thread that has
5660 completed a displaced single-step? (Doing so usually affects
5661 the PC, so do it here, before we set stop_pc.) */
5662 if (finish_step_over (ecs
))
5665 /* If we either finished a single-step or hit a breakpoint, but
5666 the user wanted this thread to be stopped, pretend we got a
5667 SIG0 (generic unsignaled stop). */
5668 if (ecs
->event_thread
->stop_requested
5669 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5670 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5672 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5676 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5677 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5678 struct cleanup
*old_chain
= save_inferior_ptid ();
5680 inferior_ptid
= ecs
->ptid
;
5682 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5683 paddress (gdbarch
, stop_pc
));
5684 if (target_stopped_by_watchpoint ())
5688 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5690 if (target_stopped_data_address (¤t_target
, &addr
))
5691 fprintf_unfiltered (gdb_stdlog
,
5692 "infrun: stopped data address = %s\n",
5693 paddress (gdbarch
, addr
));
5695 fprintf_unfiltered (gdb_stdlog
,
5696 "infrun: (no data address available)\n");
5699 do_cleanups (old_chain
);
5702 /* This is originated from start_remote(), start_inferior() and
5703 shared libraries hook functions. */
5704 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5705 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5707 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5708 context_switch (ecs
->ptid
);
5710 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5711 stop_print_frame
= 1;
5716 /* This originates from attach_command(). We need to overwrite
5717 the stop_signal here, because some kernels don't ignore a
5718 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5719 See more comments in inferior.h. On the other hand, if we
5720 get a non-SIGSTOP, report it to the user - assume the backend
5721 will handle the SIGSTOP if it should show up later.
5723 Also consider that the attach is complete when we see a
5724 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5725 target extended-remote report it instead of a SIGSTOP
5726 (e.g. gdbserver). We already rely on SIGTRAP being our
5727 signal, so this is no exception.
5729 Also consider that the attach is complete when we see a
5730 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5731 the target to stop all threads of the inferior, in case the
5732 low level attach operation doesn't stop them implicitly. If
5733 they weren't stopped implicitly, then the stub will report a
5734 GDB_SIGNAL_0, meaning: stopped for no particular reason
5735 other than GDB's request. */
5736 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5737 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5738 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5739 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5741 stop_print_frame
= 1;
5743 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5747 /* See if something interesting happened to the non-current thread. If
5748 so, then switch to that thread. */
5749 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5752 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5754 context_switch (ecs
->ptid
);
5756 if (deprecated_context_hook
)
5757 deprecated_context_hook (ptid_to_global_thread_id (ecs
->ptid
));
5760 /* At this point, get hold of the now-current thread's frame. */
5761 frame
= get_current_frame ();
5762 gdbarch
= get_frame_arch (frame
);
5764 /* Pull the single step breakpoints out of the target. */
5765 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5767 struct regcache
*regcache
;
5768 struct address_space
*aspace
;
5771 regcache
= get_thread_regcache (ecs
->ptid
);
5772 aspace
= get_regcache_aspace (regcache
);
5773 pc
= regcache_read_pc (regcache
);
5775 /* However, before doing so, if this single-step breakpoint was
5776 actually for another thread, set this thread up for moving
5778 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5781 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5785 fprintf_unfiltered (gdb_stdlog
,
5786 "infrun: [%s] hit another thread's "
5787 "single-step breakpoint\n",
5788 target_pid_to_str (ecs
->ptid
));
5790 ecs
->hit_singlestep_breakpoint
= 1;
5797 fprintf_unfiltered (gdb_stdlog
,
5798 "infrun: [%s] hit its "
5799 "single-step breakpoint\n",
5800 target_pid_to_str (ecs
->ptid
));
5804 delete_just_stopped_threads_single_step_breakpoints ();
5806 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5807 && ecs
->event_thread
->control
.trap_expected
5808 && ecs
->event_thread
->stepping_over_watchpoint
)
5809 stopped_by_watchpoint
= 0;
5811 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5813 /* If necessary, step over this watchpoint. We'll be back to display
5815 if (stopped_by_watchpoint
5816 && (target_have_steppable_watchpoint
5817 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5819 /* At this point, we are stopped at an instruction which has
5820 attempted to write to a piece of memory under control of
5821 a watchpoint. The instruction hasn't actually executed
5822 yet. If we were to evaluate the watchpoint expression
5823 now, we would get the old value, and therefore no change
5824 would seem to have occurred.
5826 In order to make watchpoints work `right', we really need
5827 to complete the memory write, and then evaluate the
5828 watchpoint expression. We do this by single-stepping the
5831 It may not be necessary to disable the watchpoint to step over
5832 it. For example, the PA can (with some kernel cooperation)
5833 single step over a watchpoint without disabling the watchpoint.
5835 It is far more common to need to disable a watchpoint to step
5836 the inferior over it. If we have non-steppable watchpoints,
5837 we must disable the current watchpoint; it's simplest to
5838 disable all watchpoints.
5840 Any breakpoint at PC must also be stepped over -- if there's
5841 one, it will have already triggered before the watchpoint
5842 triggered, and we either already reported it to the user, or
5843 it didn't cause a stop and we called keep_going. In either
5844 case, if there was a breakpoint at PC, we must be trying to
5846 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5851 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5852 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5853 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5854 ecs
->event_thread
->control
.stop_step
= 0;
5855 stop_print_frame
= 1;
5856 stopped_by_random_signal
= 0;
5858 /* Hide inlined functions starting here, unless we just performed stepi or
5859 nexti. After stepi and nexti, always show the innermost frame (not any
5860 inline function call sites). */
5861 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5863 struct address_space
*aspace
=
5864 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5866 /* skip_inline_frames is expensive, so we avoid it if we can
5867 determine that the address is one where functions cannot have
5868 been inlined. This improves performance with inferiors that
5869 load a lot of shared libraries, because the solib event
5870 breakpoint is defined as the address of a function (i.e. not
5871 inline). Note that we have to check the previous PC as well
5872 as the current one to catch cases when we have just
5873 single-stepped off a breakpoint prior to reinstating it.
5874 Note that we're assuming that the code we single-step to is
5875 not inline, but that's not definitive: there's nothing
5876 preventing the event breakpoint function from containing
5877 inlined code, and the single-step ending up there. If the
5878 user had set a breakpoint on that inlined code, the missing
5879 skip_inline_frames call would break things. Fortunately
5880 that's an extremely unlikely scenario. */
5881 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5882 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5883 && ecs
->event_thread
->control
.trap_expected
5884 && pc_at_non_inline_function (aspace
,
5885 ecs
->event_thread
->prev_pc
,
5888 skip_inline_frames (ecs
->ptid
);
5890 /* Re-fetch current thread's frame in case that invalidated
5892 frame
= get_current_frame ();
5893 gdbarch
= get_frame_arch (frame
);
5897 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5898 && ecs
->event_thread
->control
.trap_expected
5899 && gdbarch_single_step_through_delay_p (gdbarch
)
5900 && currently_stepping (ecs
->event_thread
))
5902 /* We're trying to step off a breakpoint. Turns out that we're
5903 also on an instruction that needs to be stepped multiple
5904 times before it's been fully executing. E.g., architectures
5905 with a delay slot. It needs to be stepped twice, once for
5906 the instruction and once for the delay slot. */
5907 int step_through_delay
5908 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5910 if (debug_infrun
&& step_through_delay
)
5911 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5912 if (ecs
->event_thread
->control
.step_range_end
== 0
5913 && step_through_delay
)
5915 /* The user issued a continue when stopped at a breakpoint.
5916 Set up for another trap and get out of here. */
5917 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5921 else if (step_through_delay
)
5923 /* The user issued a step when stopped at a breakpoint.
5924 Maybe we should stop, maybe we should not - the delay
5925 slot *might* correspond to a line of source. In any
5926 case, don't decide that here, just set
5927 ecs->stepping_over_breakpoint, making sure we
5928 single-step again before breakpoints are re-inserted. */
5929 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5933 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5934 handles this event. */
5935 ecs
->event_thread
->control
.stop_bpstat
5936 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5937 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5939 /* Following in case break condition called a
5941 stop_print_frame
= 1;
5943 /* This is where we handle "moribund" watchpoints. Unlike
5944 software breakpoints traps, hardware watchpoint traps are
5945 always distinguishable from random traps. If no high-level
5946 watchpoint is associated with the reported stop data address
5947 anymore, then the bpstat does not explain the signal ---
5948 simply make sure to ignore it if `stopped_by_watchpoint' is
5952 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5953 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5955 && stopped_by_watchpoint
)
5956 fprintf_unfiltered (gdb_stdlog
,
5957 "infrun: no user watchpoint explains "
5958 "watchpoint SIGTRAP, ignoring\n");
5960 /* NOTE: cagney/2003-03-29: These checks for a random signal
5961 at one stage in the past included checks for an inferior
5962 function call's call dummy's return breakpoint. The original
5963 comment, that went with the test, read:
5965 ``End of a stack dummy. Some systems (e.g. Sony news) give
5966 another signal besides SIGTRAP, so check here as well as
5969 If someone ever tries to get call dummys on a
5970 non-executable stack to work (where the target would stop
5971 with something like a SIGSEGV), then those tests might need
5972 to be re-instated. Given, however, that the tests were only
5973 enabled when momentary breakpoints were not being used, I
5974 suspect that it won't be the case.
5976 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5977 be necessary for call dummies on a non-executable stack on
5980 /* See if the breakpoints module can explain the signal. */
5982 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5983 ecs
->event_thread
->suspend
.stop_signal
);
5985 /* Maybe this was a trap for a software breakpoint that has since
5987 if (random_signal
&& target_stopped_by_sw_breakpoint ())
5989 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
5991 struct regcache
*regcache
;
5994 /* Re-adjust PC to what the program would see if GDB was not
5996 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
5997 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6000 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
6002 if (record_full_is_used ())
6003 record_full_gdb_operation_disable_set ();
6005 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
6007 do_cleanups (old_cleanups
);
6012 /* A delayed software breakpoint event. Ignore the trap. */
6014 fprintf_unfiltered (gdb_stdlog
,
6015 "infrun: delayed software breakpoint "
6016 "trap, ignoring\n");
6021 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6022 has since been removed. */
6023 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6025 /* A delayed hardware breakpoint event. Ignore the trap. */
6027 fprintf_unfiltered (gdb_stdlog
,
6028 "infrun: delayed hardware breakpoint/watchpoint "
6029 "trap, ignoring\n");
6033 /* If not, perhaps stepping/nexting can. */
6035 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6036 && currently_stepping (ecs
->event_thread
));
6038 /* Perhaps the thread hit a single-step breakpoint of _another_
6039 thread. Single-step breakpoints are transparent to the
6040 breakpoints module. */
6042 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6044 /* No? Perhaps we got a moribund watchpoint. */
6046 random_signal
= !stopped_by_watchpoint
;
6048 /* For the program's own signals, act according to
6049 the signal handling tables. */
6053 /* Signal not for debugging purposes. */
6054 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
6055 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6058 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
6059 gdb_signal_to_symbol_string (stop_signal
));
6061 stopped_by_random_signal
= 1;
6063 /* Always stop on signals if we're either just gaining control
6064 of the program, or the user explicitly requested this thread
6065 to remain stopped. */
6066 if (stop_soon
!= NO_STOP_QUIETLY
6067 || ecs
->event_thread
->stop_requested
6069 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
6075 /* Notify observers the signal has "handle print" set. Note we
6076 returned early above if stopping; normal_stop handles the
6077 printing in that case. */
6078 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6080 /* The signal table tells us to print about this signal. */
6081 target_terminal_ours_for_output ();
6082 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
6083 target_terminal_inferior ();
6086 /* Clear the signal if it should not be passed. */
6087 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6088 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6090 if (ecs
->event_thread
->prev_pc
== stop_pc
6091 && ecs
->event_thread
->control
.trap_expected
6092 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6096 /* We were just starting a new sequence, attempting to
6097 single-step off of a breakpoint and expecting a SIGTRAP.
6098 Instead this signal arrives. This signal will take us out
6099 of the stepping range so GDB needs to remember to, when
6100 the signal handler returns, resume stepping off that
6102 /* To simplify things, "continue" is forced to use the same
6103 code paths as single-step - set a breakpoint at the
6104 signal return address and then, once hit, step off that
6107 fprintf_unfiltered (gdb_stdlog
,
6108 "infrun: signal arrived while stepping over "
6111 was_in_line
= step_over_info_valid_p ();
6112 clear_step_over_info ();
6113 insert_hp_step_resume_breakpoint_at_frame (frame
);
6114 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6115 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6116 ecs
->event_thread
->control
.trap_expected
= 0;
6118 if (target_is_non_stop_p ())
6120 /* Either "set non-stop" is "on", or the target is
6121 always in non-stop mode. In this case, we have a bit
6122 more work to do. Resume the current thread, and if
6123 we had paused all threads, restart them while the
6124 signal handler runs. */
6129 restart_threads (ecs
->event_thread
);
6131 else if (debug_infrun
)
6133 fprintf_unfiltered (gdb_stdlog
,
6134 "infrun: no need to restart threads\n");
6139 /* If we were nexting/stepping some other thread, switch to
6140 it, so that we don't continue it, losing control. */
6141 if (!switch_back_to_stepped_thread (ecs
))
6146 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6147 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6148 || ecs
->event_thread
->control
.step_range_end
== 1)
6149 && frame_id_eq (get_stack_frame_id (frame
),
6150 ecs
->event_thread
->control
.step_stack_frame_id
)
6151 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6153 /* The inferior is about to take a signal that will take it
6154 out of the single step range. Set a breakpoint at the
6155 current PC (which is presumably where the signal handler
6156 will eventually return) and then allow the inferior to
6159 Note that this is only needed for a signal delivered
6160 while in the single-step range. Nested signals aren't a
6161 problem as they eventually all return. */
6163 fprintf_unfiltered (gdb_stdlog
,
6164 "infrun: signal may take us out of "
6165 "single-step range\n");
6167 clear_step_over_info ();
6168 insert_hp_step_resume_breakpoint_at_frame (frame
);
6169 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6170 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6171 ecs
->event_thread
->control
.trap_expected
= 0;
6176 /* Note: step_resume_breakpoint may be non-NULL. This occures
6177 when either there's a nested signal, or when there's a
6178 pending signal enabled just as the signal handler returns
6179 (leaving the inferior at the step-resume-breakpoint without
6180 actually executing it). Either way continue until the
6181 breakpoint is really hit. */
6183 if (!switch_back_to_stepped_thread (ecs
))
6186 fprintf_unfiltered (gdb_stdlog
,
6187 "infrun: random signal, keep going\n");
6194 process_event_stop_test (ecs
);
6197 /* Come here when we've got some debug event / signal we can explain
6198 (IOW, not a random signal), and test whether it should cause a
6199 stop, or whether we should resume the inferior (transparently).
6200 E.g., could be a breakpoint whose condition evaluates false; we
6201 could be still stepping within the line; etc. */
6204 process_event_stop_test (struct execution_control_state
*ecs
)
6206 struct symtab_and_line stop_pc_sal
;
6207 struct frame_info
*frame
;
6208 struct gdbarch
*gdbarch
;
6209 CORE_ADDR jmp_buf_pc
;
6210 struct bpstat_what what
;
6212 /* Handle cases caused by hitting a breakpoint. */
6214 frame
= get_current_frame ();
6215 gdbarch
= get_frame_arch (frame
);
6217 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6219 if (what
.call_dummy
)
6221 stop_stack_dummy
= what
.call_dummy
;
6224 /* A few breakpoint types have callbacks associated (e.g.,
6225 bp_jit_event). Run them now. */
6226 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6228 /* If we hit an internal event that triggers symbol changes, the
6229 current frame will be invalidated within bpstat_what (e.g., if we
6230 hit an internal solib event). Re-fetch it. */
6231 frame
= get_current_frame ();
6232 gdbarch
= get_frame_arch (frame
);
6234 switch (what
.main_action
)
6236 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6237 /* If we hit the breakpoint at longjmp while stepping, we
6238 install a momentary breakpoint at the target of the
6242 fprintf_unfiltered (gdb_stdlog
,
6243 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6245 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6247 if (what
.is_longjmp
)
6249 struct value
*arg_value
;
6251 /* If we set the longjmp breakpoint via a SystemTap probe,
6252 then use it to extract the arguments. The destination PC
6253 is the third argument to the probe. */
6254 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6257 jmp_buf_pc
= value_as_address (arg_value
);
6258 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6260 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6261 || !gdbarch_get_longjmp_target (gdbarch
,
6262 frame
, &jmp_buf_pc
))
6265 fprintf_unfiltered (gdb_stdlog
,
6266 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6267 "(!gdbarch_get_longjmp_target)\n");
6272 /* Insert a breakpoint at resume address. */
6273 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6276 check_exception_resume (ecs
, frame
);
6280 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6282 struct frame_info
*init_frame
;
6284 /* There are several cases to consider.
6286 1. The initiating frame no longer exists. In this case we
6287 must stop, because the exception or longjmp has gone too
6290 2. The initiating frame exists, and is the same as the
6291 current frame. We stop, because the exception or longjmp
6294 3. The initiating frame exists and is different from the
6295 current frame. This means the exception or longjmp has
6296 been caught beneath the initiating frame, so keep going.
6298 4. longjmp breakpoint has been placed just to protect
6299 against stale dummy frames and user is not interested in
6300 stopping around longjmps. */
6303 fprintf_unfiltered (gdb_stdlog
,
6304 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6306 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6308 delete_exception_resume_breakpoint (ecs
->event_thread
);
6310 if (what
.is_longjmp
)
6312 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6314 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6322 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6326 struct frame_id current_id
6327 = get_frame_id (get_current_frame ());
6328 if (frame_id_eq (current_id
,
6329 ecs
->event_thread
->initiating_frame
))
6331 /* Case 2. Fall through. */
6341 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6343 delete_step_resume_breakpoint (ecs
->event_thread
);
6345 end_stepping_range (ecs
);
6349 case BPSTAT_WHAT_SINGLE
:
6351 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6352 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6353 /* Still need to check other stuff, at least the case where we
6354 are stepping and step out of the right range. */
6357 case BPSTAT_WHAT_STEP_RESUME
:
6359 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6361 delete_step_resume_breakpoint (ecs
->event_thread
);
6362 if (ecs
->event_thread
->control
.proceed_to_finish
6363 && execution_direction
== EXEC_REVERSE
)
6365 struct thread_info
*tp
= ecs
->event_thread
;
6367 /* We are finishing a function in reverse, and just hit the
6368 step-resume breakpoint at the start address of the
6369 function, and we're almost there -- just need to back up
6370 by one more single-step, which should take us back to the
6372 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6376 fill_in_stop_func (gdbarch
, ecs
);
6377 if (stop_pc
== ecs
->stop_func_start
6378 && execution_direction
== EXEC_REVERSE
)
6380 /* We are stepping over a function call in reverse, and just
6381 hit the step-resume breakpoint at the start address of
6382 the function. Go back to single-stepping, which should
6383 take us back to the function call. */
6384 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6390 case BPSTAT_WHAT_STOP_NOISY
:
6392 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6393 stop_print_frame
= 1;
6395 /* Assume the thread stopped for a breapoint. We'll still check
6396 whether a/the breakpoint is there when the thread is next
6398 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6403 case BPSTAT_WHAT_STOP_SILENT
:
6405 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6406 stop_print_frame
= 0;
6408 /* Assume the thread stopped for a breapoint. We'll still check
6409 whether a/the breakpoint is there when the thread is next
6411 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6415 case BPSTAT_WHAT_HP_STEP_RESUME
:
6417 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6419 delete_step_resume_breakpoint (ecs
->event_thread
);
6420 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6422 /* Back when the step-resume breakpoint was inserted, we
6423 were trying to single-step off a breakpoint. Go back to
6425 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6426 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6432 case BPSTAT_WHAT_KEEP_CHECKING
:
6436 /* If we stepped a permanent breakpoint and we had a high priority
6437 step-resume breakpoint for the address we stepped, but we didn't
6438 hit it, then we must have stepped into the signal handler. The
6439 step-resume was only necessary to catch the case of _not_
6440 stepping into the handler, so delete it, and fall through to
6441 checking whether the step finished. */
6442 if (ecs
->event_thread
->stepped_breakpoint
)
6444 struct breakpoint
*sr_bp
6445 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6448 && sr_bp
->loc
->permanent
6449 && sr_bp
->type
== bp_hp_step_resume
6450 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6453 fprintf_unfiltered (gdb_stdlog
,
6454 "infrun: stepped permanent breakpoint, stopped in "
6456 delete_step_resume_breakpoint (ecs
->event_thread
);
6457 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6461 /* We come here if we hit a breakpoint but should not stop for it.
6462 Possibly we also were stepping and should stop for that. So fall
6463 through and test for stepping. But, if not stepping, do not
6466 /* In all-stop mode, if we're currently stepping but have stopped in
6467 some other thread, we need to switch back to the stepped thread. */
6468 if (switch_back_to_stepped_thread (ecs
))
6471 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6474 fprintf_unfiltered (gdb_stdlog
,
6475 "infrun: step-resume breakpoint is inserted\n");
6477 /* Having a step-resume breakpoint overrides anything
6478 else having to do with stepping commands until
6479 that breakpoint is reached. */
6484 if (ecs
->event_thread
->control
.step_range_end
== 0)
6487 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6488 /* Likewise if we aren't even stepping. */
6493 /* Re-fetch current thread's frame in case the code above caused
6494 the frame cache to be re-initialized, making our FRAME variable
6495 a dangling pointer. */
6496 frame
= get_current_frame ();
6497 gdbarch
= get_frame_arch (frame
);
6498 fill_in_stop_func (gdbarch
, ecs
);
6500 /* If stepping through a line, keep going if still within it.
6502 Note that step_range_end is the address of the first instruction
6503 beyond the step range, and NOT the address of the last instruction
6506 Note also that during reverse execution, we may be stepping
6507 through a function epilogue and therefore must detect when
6508 the current-frame changes in the middle of a line. */
6510 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6511 && (execution_direction
!= EXEC_REVERSE
6512 || frame_id_eq (get_frame_id (frame
),
6513 ecs
->event_thread
->control
.step_frame_id
)))
6517 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6518 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6519 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6521 /* Tentatively re-enable range stepping; `resume' disables it if
6522 necessary (e.g., if we're stepping over a breakpoint or we
6523 have software watchpoints). */
6524 ecs
->event_thread
->control
.may_range_step
= 1;
6526 /* When stepping backward, stop at beginning of line range
6527 (unless it's the function entry point, in which case
6528 keep going back to the call point). */
6529 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6530 && stop_pc
!= ecs
->stop_func_start
6531 && execution_direction
== EXEC_REVERSE
)
6532 end_stepping_range (ecs
);
6539 /* We stepped out of the stepping range. */
6541 /* If we are stepping at the source level and entered the runtime
6542 loader dynamic symbol resolution code...
6544 EXEC_FORWARD: we keep on single stepping until we exit the run
6545 time loader code and reach the callee's address.
6547 EXEC_REVERSE: we've already executed the callee (backward), and
6548 the runtime loader code is handled just like any other
6549 undebuggable function call. Now we need only keep stepping
6550 backward through the trampoline code, and that's handled further
6551 down, so there is nothing for us to do here. */
6553 if (execution_direction
!= EXEC_REVERSE
6554 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6555 && in_solib_dynsym_resolve_code (stop_pc
))
6557 CORE_ADDR pc_after_resolver
=
6558 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6561 fprintf_unfiltered (gdb_stdlog
,
6562 "infrun: stepped into dynsym resolve code\n");
6564 if (pc_after_resolver
)
6566 /* Set up a step-resume breakpoint at the address
6567 indicated by SKIP_SOLIB_RESOLVER. */
6568 struct symtab_and_line sr_sal
;
6571 sr_sal
.pc
= pc_after_resolver
;
6572 sr_sal
.pspace
= get_frame_program_space (frame
);
6574 insert_step_resume_breakpoint_at_sal (gdbarch
,
6575 sr_sal
, null_frame_id
);
6582 if (ecs
->event_thread
->control
.step_range_end
!= 1
6583 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6584 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6585 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6588 fprintf_unfiltered (gdb_stdlog
,
6589 "infrun: stepped into signal trampoline\n");
6590 /* The inferior, while doing a "step" or "next", has ended up in
6591 a signal trampoline (either by a signal being delivered or by
6592 the signal handler returning). Just single-step until the
6593 inferior leaves the trampoline (either by calling the handler
6599 /* If we're in the return path from a shared library trampoline,
6600 we want to proceed through the trampoline when stepping. */
6601 /* macro/2012-04-25: This needs to come before the subroutine
6602 call check below as on some targets return trampolines look
6603 like subroutine calls (MIPS16 return thunks). */
6604 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6605 stop_pc
, ecs
->stop_func_name
)
6606 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6608 /* Determine where this trampoline returns. */
6609 CORE_ADDR real_stop_pc
;
6611 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6614 fprintf_unfiltered (gdb_stdlog
,
6615 "infrun: stepped into solib return tramp\n");
6617 /* Only proceed through if we know where it's going. */
6620 /* And put the step-breakpoint there and go until there. */
6621 struct symtab_and_line sr_sal
;
6623 init_sal (&sr_sal
); /* initialize to zeroes */
6624 sr_sal
.pc
= real_stop_pc
;
6625 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6626 sr_sal
.pspace
= get_frame_program_space (frame
);
6628 /* Do not specify what the fp should be when we stop since
6629 on some machines the prologue is where the new fp value
6631 insert_step_resume_breakpoint_at_sal (gdbarch
,
6632 sr_sal
, null_frame_id
);
6634 /* Restart without fiddling with the step ranges or
6641 /* Check for subroutine calls. The check for the current frame
6642 equalling the step ID is not necessary - the check of the
6643 previous frame's ID is sufficient - but it is a common case and
6644 cheaper than checking the previous frame's ID.
6646 NOTE: frame_id_eq will never report two invalid frame IDs as
6647 being equal, so to get into this block, both the current and
6648 previous frame must have valid frame IDs. */
6649 /* The outer_frame_id check is a heuristic to detect stepping
6650 through startup code. If we step over an instruction which
6651 sets the stack pointer from an invalid value to a valid value,
6652 we may detect that as a subroutine call from the mythical
6653 "outermost" function. This could be fixed by marking
6654 outermost frames as !stack_p,code_p,special_p. Then the
6655 initial outermost frame, before sp was valid, would
6656 have code_addr == &_start. See the comment in frame_id_eq
6658 if (!frame_id_eq (get_stack_frame_id (frame
),
6659 ecs
->event_thread
->control
.step_stack_frame_id
)
6660 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6661 ecs
->event_thread
->control
.step_stack_frame_id
)
6662 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6664 || (ecs
->event_thread
->control
.step_start_function
6665 != find_pc_function (stop_pc
)))))
6667 CORE_ADDR real_stop_pc
;
6670 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6672 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6674 /* I presume that step_over_calls is only 0 when we're
6675 supposed to be stepping at the assembly language level
6676 ("stepi"). Just stop. */
6677 /* And this works the same backward as frontward. MVS */
6678 end_stepping_range (ecs
);
6682 /* Reverse stepping through solib trampolines. */
6684 if (execution_direction
== EXEC_REVERSE
6685 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6686 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6687 || (ecs
->stop_func_start
== 0
6688 && in_solib_dynsym_resolve_code (stop_pc
))))
6690 /* Any solib trampoline code can be handled in reverse
6691 by simply continuing to single-step. We have already
6692 executed the solib function (backwards), and a few
6693 steps will take us back through the trampoline to the
6699 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6701 /* We're doing a "next".
6703 Normal (forward) execution: set a breakpoint at the
6704 callee's return address (the address at which the caller
6707 Reverse (backward) execution. set the step-resume
6708 breakpoint at the start of the function that we just
6709 stepped into (backwards), and continue to there. When we
6710 get there, we'll need to single-step back to the caller. */
6712 if (execution_direction
== EXEC_REVERSE
)
6714 /* If we're already at the start of the function, we've either
6715 just stepped backward into a single instruction function,
6716 or stepped back out of a signal handler to the first instruction
6717 of the function. Just keep going, which will single-step back
6719 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6721 struct symtab_and_line sr_sal
;
6723 /* Normal function call return (static or dynamic). */
6725 sr_sal
.pc
= ecs
->stop_func_start
;
6726 sr_sal
.pspace
= get_frame_program_space (frame
);
6727 insert_step_resume_breakpoint_at_sal (gdbarch
,
6728 sr_sal
, null_frame_id
);
6732 insert_step_resume_breakpoint_at_caller (frame
);
6738 /* If we are in a function call trampoline (a stub between the
6739 calling routine and the real function), locate the real
6740 function. That's what tells us (a) whether we want to step
6741 into it at all, and (b) what prologue we want to run to the
6742 end of, if we do step into it. */
6743 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6744 if (real_stop_pc
== 0)
6745 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6746 if (real_stop_pc
!= 0)
6747 ecs
->stop_func_start
= real_stop_pc
;
6749 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6751 struct symtab_and_line sr_sal
;
6754 sr_sal
.pc
= ecs
->stop_func_start
;
6755 sr_sal
.pspace
= get_frame_program_space (frame
);
6757 insert_step_resume_breakpoint_at_sal (gdbarch
,
6758 sr_sal
, null_frame_id
);
6763 /* If we have line number information for the function we are
6764 thinking of stepping into and the function isn't on the skip
6767 If there are several symtabs at that PC (e.g. with include
6768 files), just want to know whether *any* of them have line
6769 numbers. find_pc_line handles this. */
6771 struct symtab_and_line tmp_sal
;
6773 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6774 if (tmp_sal
.line
!= 0
6775 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6778 if (execution_direction
== EXEC_REVERSE
)
6779 handle_step_into_function_backward (gdbarch
, ecs
);
6781 handle_step_into_function (gdbarch
, ecs
);
6786 /* If we have no line number and the step-stop-if-no-debug is
6787 set, we stop the step so that the user has a chance to switch
6788 in assembly mode. */
6789 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6790 && step_stop_if_no_debug
)
6792 end_stepping_range (ecs
);
6796 if (execution_direction
== EXEC_REVERSE
)
6798 /* If we're already at the start of the function, we've either just
6799 stepped backward into a single instruction function without line
6800 number info, or stepped back out of a signal handler to the first
6801 instruction of the function without line number info. Just keep
6802 going, which will single-step back to the caller. */
6803 if (ecs
->stop_func_start
!= stop_pc
)
6805 /* Set a breakpoint at callee's start address.
6806 From there we can step once and be back in the caller. */
6807 struct symtab_and_line sr_sal
;
6810 sr_sal
.pc
= ecs
->stop_func_start
;
6811 sr_sal
.pspace
= get_frame_program_space (frame
);
6812 insert_step_resume_breakpoint_at_sal (gdbarch
,
6813 sr_sal
, null_frame_id
);
6817 /* Set a breakpoint at callee's return address (the address
6818 at which the caller will resume). */
6819 insert_step_resume_breakpoint_at_caller (frame
);
6825 /* Reverse stepping through solib trampolines. */
6827 if (execution_direction
== EXEC_REVERSE
6828 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6830 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6831 || (ecs
->stop_func_start
== 0
6832 && in_solib_dynsym_resolve_code (stop_pc
)))
6834 /* Any solib trampoline code can be handled in reverse
6835 by simply continuing to single-step. We have already
6836 executed the solib function (backwards), and a few
6837 steps will take us back through the trampoline to the
6842 else if (in_solib_dynsym_resolve_code (stop_pc
))
6844 /* Stepped backward into the solib dynsym resolver.
6845 Set a breakpoint at its start and continue, then
6846 one more step will take us out. */
6847 struct symtab_and_line sr_sal
;
6850 sr_sal
.pc
= ecs
->stop_func_start
;
6851 sr_sal
.pspace
= get_frame_program_space (frame
);
6852 insert_step_resume_breakpoint_at_sal (gdbarch
,
6853 sr_sal
, null_frame_id
);
6859 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6861 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6862 the trampoline processing logic, however, there are some trampolines
6863 that have no names, so we should do trampoline handling first. */
6864 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6865 && ecs
->stop_func_name
== NULL
6866 && stop_pc_sal
.line
== 0)
6869 fprintf_unfiltered (gdb_stdlog
,
6870 "infrun: stepped into undebuggable function\n");
6872 /* The inferior just stepped into, or returned to, an
6873 undebuggable function (where there is no debugging information
6874 and no line number corresponding to the address where the
6875 inferior stopped). Since we want to skip this kind of code,
6876 we keep going until the inferior returns from this
6877 function - unless the user has asked us not to (via
6878 set step-mode) or we no longer know how to get back
6879 to the call site. */
6880 if (step_stop_if_no_debug
6881 || !frame_id_p (frame_unwind_caller_id (frame
)))
6883 /* If we have no line number and the step-stop-if-no-debug
6884 is set, we stop the step so that the user has a chance to
6885 switch in assembly mode. */
6886 end_stepping_range (ecs
);
6891 /* Set a breakpoint at callee's return address (the address
6892 at which the caller will resume). */
6893 insert_step_resume_breakpoint_at_caller (frame
);
6899 if (ecs
->event_thread
->control
.step_range_end
== 1)
6901 /* It is stepi or nexti. We always want to stop stepping after
6904 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6905 end_stepping_range (ecs
);
6909 if (stop_pc_sal
.line
== 0)
6911 /* We have no line number information. That means to stop
6912 stepping (does this always happen right after one instruction,
6913 when we do "s" in a function with no line numbers,
6914 or can this happen as a result of a return or longjmp?). */
6916 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6917 end_stepping_range (ecs
);
6921 /* Look for "calls" to inlined functions, part one. If the inline
6922 frame machinery detected some skipped call sites, we have entered
6923 a new inline function. */
6925 if (frame_id_eq (get_frame_id (get_current_frame ()),
6926 ecs
->event_thread
->control
.step_frame_id
)
6927 && inline_skipped_frames (ecs
->ptid
))
6929 struct symtab_and_line call_sal
;
6932 fprintf_unfiltered (gdb_stdlog
,
6933 "infrun: stepped into inlined function\n");
6935 find_frame_sal (get_current_frame (), &call_sal
);
6937 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6939 /* For "step", we're going to stop. But if the call site
6940 for this inlined function is on the same source line as
6941 we were previously stepping, go down into the function
6942 first. Otherwise stop at the call site. */
6944 if (call_sal
.line
== ecs
->event_thread
->current_line
6945 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6946 step_into_inline_frame (ecs
->ptid
);
6948 end_stepping_range (ecs
);
6953 /* For "next", we should stop at the call site if it is on a
6954 different source line. Otherwise continue through the
6955 inlined function. */
6956 if (call_sal
.line
== ecs
->event_thread
->current_line
6957 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6960 end_stepping_range (ecs
);
6965 /* Look for "calls" to inlined functions, part two. If we are still
6966 in the same real function we were stepping through, but we have
6967 to go further up to find the exact frame ID, we are stepping
6968 through a more inlined call beyond its call site. */
6970 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6971 && !frame_id_eq (get_frame_id (get_current_frame ()),
6972 ecs
->event_thread
->control
.step_frame_id
)
6973 && stepped_in_from (get_current_frame (),
6974 ecs
->event_thread
->control
.step_frame_id
))
6977 fprintf_unfiltered (gdb_stdlog
,
6978 "infrun: stepping through inlined function\n");
6980 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6983 end_stepping_range (ecs
);
6987 if ((stop_pc
== stop_pc_sal
.pc
)
6988 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6989 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6991 /* We are at the start of a different line. So stop. Note that
6992 we don't stop if we step into the middle of a different line.
6993 That is said to make things like for (;;) statements work
6996 fprintf_unfiltered (gdb_stdlog
,
6997 "infrun: stepped to a different line\n");
6998 end_stepping_range (ecs
);
7002 /* We aren't done stepping.
7004 Optimize by setting the stepping range to the line.
7005 (We might not be in the original line, but if we entered a
7006 new line in mid-statement, we continue stepping. This makes
7007 things like for(;;) statements work better.) */
7009 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7010 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7011 ecs
->event_thread
->control
.may_range_step
= 1;
7012 set_step_info (frame
, stop_pc_sal
);
7015 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
7019 /* In all-stop mode, if we're currently stepping but have stopped in
7020 some other thread, we may need to switch back to the stepped
7021 thread. Returns true we set the inferior running, false if we left
7022 it stopped (and the event needs further processing). */
7025 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7027 if (!target_is_non_stop_p ())
7029 struct thread_info
*tp
;
7030 struct thread_info
*stepping_thread
;
7032 /* If any thread is blocked on some internal breakpoint, and we
7033 simply need to step over that breakpoint to get it going
7034 again, do that first. */
7036 /* However, if we see an event for the stepping thread, then we
7037 know all other threads have been moved past their breakpoints
7038 already. Let the caller check whether the step is finished,
7039 etc., before deciding to move it past a breakpoint. */
7040 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7043 /* Check if the current thread is blocked on an incomplete
7044 step-over, interrupted by a random signal. */
7045 if (ecs
->event_thread
->control
.trap_expected
7046 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7050 fprintf_unfiltered (gdb_stdlog
,
7051 "infrun: need to finish step-over of [%s]\n",
7052 target_pid_to_str (ecs
->event_thread
->ptid
));
7058 /* Check if the current thread is blocked by a single-step
7059 breakpoint of another thread. */
7060 if (ecs
->hit_singlestep_breakpoint
)
7064 fprintf_unfiltered (gdb_stdlog
,
7065 "infrun: need to step [%s] over single-step "
7067 target_pid_to_str (ecs
->ptid
));
7073 /* If this thread needs yet another step-over (e.g., stepping
7074 through a delay slot), do it first before moving on to
7076 if (thread_still_needs_step_over (ecs
->event_thread
))
7080 fprintf_unfiltered (gdb_stdlog
,
7081 "infrun: thread [%s] still needs step-over\n",
7082 target_pid_to_str (ecs
->event_thread
->ptid
));
7088 /* If scheduler locking applies even if not stepping, there's no
7089 need to walk over threads. Above we've checked whether the
7090 current thread is stepping. If some other thread not the
7091 event thread is stepping, then it must be that scheduler
7092 locking is not in effect. */
7093 if (schedlock_applies (ecs
->event_thread
))
7096 /* Otherwise, we no longer expect a trap in the current thread.
7097 Clear the trap_expected flag before switching back -- this is
7098 what keep_going does as well, if we call it. */
7099 ecs
->event_thread
->control
.trap_expected
= 0;
7101 /* Likewise, clear the signal if it should not be passed. */
7102 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7103 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7105 /* Do all pending step-overs before actually proceeding with
7107 if (start_step_over ())
7109 prepare_to_wait (ecs
);
7113 /* Look for the stepping/nexting thread. */
7114 stepping_thread
= NULL
;
7116 ALL_NON_EXITED_THREADS (tp
)
7118 /* Ignore threads of processes the caller is not
7121 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
7124 /* When stepping over a breakpoint, we lock all threads
7125 except the one that needs to move past the breakpoint.
7126 If a non-event thread has this set, the "incomplete
7127 step-over" check above should have caught it earlier. */
7128 if (tp
->control
.trap_expected
)
7130 internal_error (__FILE__
, __LINE__
,
7131 "[%s] has inconsistent state: "
7132 "trap_expected=%d\n",
7133 target_pid_to_str (tp
->ptid
),
7134 tp
->control
.trap_expected
);
7137 /* Did we find the stepping thread? */
7138 if (tp
->control
.step_range_end
)
7140 /* Yep. There should only one though. */
7141 gdb_assert (stepping_thread
== NULL
);
7143 /* The event thread is handled at the top, before we
7145 gdb_assert (tp
!= ecs
->event_thread
);
7147 /* If some thread other than the event thread is
7148 stepping, then scheduler locking can't be in effect,
7149 otherwise we wouldn't have resumed the current event
7150 thread in the first place. */
7151 gdb_assert (!schedlock_applies (tp
));
7153 stepping_thread
= tp
;
7157 if (stepping_thread
!= NULL
)
7160 fprintf_unfiltered (gdb_stdlog
,
7161 "infrun: switching back to stepped thread\n");
7163 if (keep_going_stepped_thread (stepping_thread
))
7165 prepare_to_wait (ecs
);
7174 /* Set a previously stepped thread back to stepping. Returns true on
7175 success, false if the resume is not possible (e.g., the thread
7179 keep_going_stepped_thread (struct thread_info
*tp
)
7181 struct frame_info
*frame
;
7182 struct execution_control_state ecss
;
7183 struct execution_control_state
*ecs
= &ecss
;
7185 /* If the stepping thread exited, then don't try to switch back and
7186 resume it, which could fail in several different ways depending
7187 on the target. Instead, just keep going.
7189 We can find a stepping dead thread in the thread list in two
7192 - The target supports thread exit events, and when the target
7193 tries to delete the thread from the thread list, inferior_ptid
7194 pointed at the exiting thread. In such case, calling
7195 delete_thread does not really remove the thread from the list;
7196 instead, the thread is left listed, with 'exited' state.
7198 - The target's debug interface does not support thread exit
7199 events, and so we have no idea whatsoever if the previously
7200 stepping thread is still alive. For that reason, we need to
7201 synchronously query the target now. */
7203 if (is_exited (tp
->ptid
)
7204 || !target_thread_alive (tp
->ptid
))
7207 fprintf_unfiltered (gdb_stdlog
,
7208 "infrun: not resuming previously "
7209 "stepped thread, it has vanished\n");
7211 delete_thread (tp
->ptid
);
7216 fprintf_unfiltered (gdb_stdlog
,
7217 "infrun: resuming previously stepped thread\n");
7219 reset_ecs (ecs
, tp
);
7220 switch_to_thread (tp
->ptid
);
7222 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7223 frame
= get_current_frame ();
7225 /* If the PC of the thread we were trying to single-step has
7226 changed, then that thread has trapped or been signaled, but the
7227 event has not been reported to GDB yet. Re-poll the target
7228 looking for this particular thread's event (i.e. temporarily
7229 enable schedlock) by:
7231 - setting a break at the current PC
7232 - resuming that particular thread, only (by setting trap
7235 This prevents us continuously moving the single-step breakpoint
7236 forward, one instruction at a time, overstepping. */
7238 if (stop_pc
!= tp
->prev_pc
)
7243 fprintf_unfiltered (gdb_stdlog
,
7244 "infrun: expected thread advanced also (%s -> %s)\n",
7245 paddress (target_gdbarch (), tp
->prev_pc
),
7246 paddress (target_gdbarch (), stop_pc
));
7248 /* Clear the info of the previous step-over, as it's no longer
7249 valid (if the thread was trying to step over a breakpoint, it
7250 has already succeeded). It's what keep_going would do too,
7251 if we called it. Do this before trying to insert the sss
7252 breakpoint, otherwise if we were previously trying to step
7253 over this exact address in another thread, the breakpoint is
7255 clear_step_over_info ();
7256 tp
->control
.trap_expected
= 0;
7258 insert_single_step_breakpoint (get_frame_arch (frame
),
7259 get_frame_address_space (frame
),
7263 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7264 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7269 fprintf_unfiltered (gdb_stdlog
,
7270 "infrun: expected thread still hasn't advanced\n");
7272 keep_going_pass_signal (ecs
);
7277 /* Is thread TP in the middle of (software or hardware)
7278 single-stepping? (Note the result of this function must never be
7279 passed directly as target_resume's STEP parameter.) */
7282 currently_stepping (struct thread_info
*tp
)
7284 return ((tp
->control
.step_range_end
7285 && tp
->control
.step_resume_breakpoint
== NULL
)
7286 || tp
->control
.trap_expected
7287 || tp
->stepped_breakpoint
7288 || bpstat_should_step ());
7291 /* Inferior has stepped into a subroutine call with source code that
7292 we should not step over. Do step to the first line of code in
7296 handle_step_into_function (struct gdbarch
*gdbarch
,
7297 struct execution_control_state
*ecs
)
7299 struct compunit_symtab
*cust
;
7300 struct symtab_and_line stop_func_sal
, sr_sal
;
7302 fill_in_stop_func (gdbarch
, ecs
);
7304 cust
= find_pc_compunit_symtab (stop_pc
);
7305 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7306 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7307 ecs
->stop_func_start
);
7309 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7310 /* Use the step_resume_break to step until the end of the prologue,
7311 even if that involves jumps (as it seems to on the vax under
7313 /* If the prologue ends in the middle of a source line, continue to
7314 the end of that source line (if it is still within the function).
7315 Otherwise, just go to end of prologue. */
7316 if (stop_func_sal
.end
7317 && stop_func_sal
.pc
!= ecs
->stop_func_start
7318 && stop_func_sal
.end
< ecs
->stop_func_end
)
7319 ecs
->stop_func_start
= stop_func_sal
.end
;
7321 /* Architectures which require breakpoint adjustment might not be able
7322 to place a breakpoint at the computed address. If so, the test
7323 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7324 ecs->stop_func_start to an address at which a breakpoint may be
7325 legitimately placed.
7327 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7328 made, GDB will enter an infinite loop when stepping through
7329 optimized code consisting of VLIW instructions which contain
7330 subinstructions corresponding to different source lines. On
7331 FR-V, it's not permitted to place a breakpoint on any but the
7332 first subinstruction of a VLIW instruction. When a breakpoint is
7333 set, GDB will adjust the breakpoint address to the beginning of
7334 the VLIW instruction. Thus, we need to make the corresponding
7335 adjustment here when computing the stop address. */
7337 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7339 ecs
->stop_func_start
7340 = gdbarch_adjust_breakpoint_address (gdbarch
,
7341 ecs
->stop_func_start
);
7344 if (ecs
->stop_func_start
== stop_pc
)
7346 /* We are already there: stop now. */
7347 end_stepping_range (ecs
);
7352 /* Put the step-breakpoint there and go until there. */
7353 init_sal (&sr_sal
); /* initialize to zeroes */
7354 sr_sal
.pc
= ecs
->stop_func_start
;
7355 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7356 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7358 /* Do not specify what the fp should be when we stop since on
7359 some machines the prologue is where the new fp value is
7361 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7363 /* And make sure stepping stops right away then. */
7364 ecs
->event_thread
->control
.step_range_end
7365 = ecs
->event_thread
->control
.step_range_start
;
7370 /* Inferior has stepped backward into a subroutine call with source
7371 code that we should not step over. Do step to the beginning of the
7372 last line of code in it. */
7375 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7376 struct execution_control_state
*ecs
)
7378 struct compunit_symtab
*cust
;
7379 struct symtab_and_line stop_func_sal
;
7381 fill_in_stop_func (gdbarch
, ecs
);
7383 cust
= find_pc_compunit_symtab (stop_pc
);
7384 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7385 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7386 ecs
->stop_func_start
);
7388 stop_func_sal
= find_pc_line (stop_pc
, 0);
7390 /* OK, we're just going to keep stepping here. */
7391 if (stop_func_sal
.pc
== stop_pc
)
7393 /* We're there already. Just stop stepping now. */
7394 end_stepping_range (ecs
);
7398 /* Else just reset the step range and keep going.
7399 No step-resume breakpoint, they don't work for
7400 epilogues, which can have multiple entry paths. */
7401 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7402 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7408 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7409 This is used to both functions and to skip over code. */
7412 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7413 struct symtab_and_line sr_sal
,
7414 struct frame_id sr_id
,
7415 enum bptype sr_type
)
7417 /* There should never be more than one step-resume or longjmp-resume
7418 breakpoint per thread, so we should never be setting a new
7419 step_resume_breakpoint when one is already active. */
7420 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7421 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7424 fprintf_unfiltered (gdb_stdlog
,
7425 "infrun: inserting step-resume breakpoint at %s\n",
7426 paddress (gdbarch
, sr_sal
.pc
));
7428 inferior_thread ()->control
.step_resume_breakpoint
7429 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7433 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7434 struct symtab_and_line sr_sal
,
7435 struct frame_id sr_id
)
7437 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7442 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7443 This is used to skip a potential signal handler.
7445 This is called with the interrupted function's frame. The signal
7446 handler, when it returns, will resume the interrupted function at
7450 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7452 struct symtab_and_line sr_sal
;
7453 struct gdbarch
*gdbarch
;
7455 gdb_assert (return_frame
!= NULL
);
7456 init_sal (&sr_sal
); /* initialize to zeros */
7458 gdbarch
= get_frame_arch (return_frame
);
7459 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7460 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7461 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7463 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7464 get_stack_frame_id (return_frame
),
7468 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7469 is used to skip a function after stepping into it (for "next" or if
7470 the called function has no debugging information).
7472 The current function has almost always been reached by single
7473 stepping a call or return instruction. NEXT_FRAME belongs to the
7474 current function, and the breakpoint will be set at the caller's
7477 This is a separate function rather than reusing
7478 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7479 get_prev_frame, which may stop prematurely (see the implementation
7480 of frame_unwind_caller_id for an example). */
7483 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7485 struct symtab_and_line sr_sal
;
7486 struct gdbarch
*gdbarch
;
7488 /* We shouldn't have gotten here if we don't know where the call site
7490 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7492 init_sal (&sr_sal
); /* initialize to zeros */
7494 gdbarch
= frame_unwind_caller_arch (next_frame
);
7495 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7496 frame_unwind_caller_pc (next_frame
));
7497 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7498 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7500 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7501 frame_unwind_caller_id (next_frame
));
7504 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7505 new breakpoint at the target of a jmp_buf. The handling of
7506 longjmp-resume uses the same mechanisms used for handling
7507 "step-resume" breakpoints. */
7510 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7512 /* There should never be more than one longjmp-resume breakpoint per
7513 thread, so we should never be setting a new
7514 longjmp_resume_breakpoint when one is already active. */
7515 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7518 fprintf_unfiltered (gdb_stdlog
,
7519 "infrun: inserting longjmp-resume breakpoint at %s\n",
7520 paddress (gdbarch
, pc
));
7522 inferior_thread ()->control
.exception_resume_breakpoint
=
7523 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7526 /* Insert an exception resume breakpoint. TP is the thread throwing
7527 the exception. The block B is the block of the unwinder debug hook
7528 function. FRAME is the frame corresponding to the call to this
7529 function. SYM is the symbol of the function argument holding the
7530 target PC of the exception. */
7533 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7534 const struct block
*b
,
7535 struct frame_info
*frame
,
7540 struct block_symbol vsym
;
7541 struct value
*value
;
7543 struct breakpoint
*bp
;
7545 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
7546 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7547 /* If the value was optimized out, revert to the old behavior. */
7548 if (! value_optimized_out (value
))
7550 handler
= value_as_address (value
);
7553 fprintf_unfiltered (gdb_stdlog
,
7554 "infrun: exception resume at %lx\n",
7555 (unsigned long) handler
);
7557 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7558 handler
, bp_exception_resume
);
7560 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7563 bp
->thread
= tp
->global_num
;
7564 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7567 CATCH (e
, RETURN_MASK_ERROR
)
7569 /* We want to ignore errors here. */
7574 /* A helper for check_exception_resume that sets an
7575 exception-breakpoint based on a SystemTap probe. */
7578 insert_exception_resume_from_probe (struct thread_info
*tp
,
7579 const struct bound_probe
*probe
,
7580 struct frame_info
*frame
)
7582 struct value
*arg_value
;
7584 struct breakpoint
*bp
;
7586 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7590 handler
= value_as_address (arg_value
);
7593 fprintf_unfiltered (gdb_stdlog
,
7594 "infrun: exception resume at %s\n",
7595 paddress (get_objfile_arch (probe
->objfile
),
7598 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7599 handler
, bp_exception_resume
);
7600 bp
->thread
= tp
->global_num
;
7601 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7604 /* This is called when an exception has been intercepted. Check to
7605 see whether the exception's destination is of interest, and if so,
7606 set an exception resume breakpoint there. */
7609 check_exception_resume (struct execution_control_state
*ecs
,
7610 struct frame_info
*frame
)
7612 struct bound_probe probe
;
7613 struct symbol
*func
;
7615 /* First see if this exception unwinding breakpoint was set via a
7616 SystemTap probe point. If so, the probe has two arguments: the
7617 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7618 set a breakpoint there. */
7619 probe
= find_probe_by_pc (get_frame_pc (frame
));
7622 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7626 func
= get_frame_function (frame
);
7632 const struct block
*b
;
7633 struct block_iterator iter
;
7637 /* The exception breakpoint is a thread-specific breakpoint on
7638 the unwinder's debug hook, declared as:
7640 void _Unwind_DebugHook (void *cfa, void *handler);
7642 The CFA argument indicates the frame to which control is
7643 about to be transferred. HANDLER is the destination PC.
7645 We ignore the CFA and set a temporary breakpoint at HANDLER.
7646 This is not extremely efficient but it avoids issues in gdb
7647 with computing the DWARF CFA, and it also works even in weird
7648 cases such as throwing an exception from inside a signal
7651 b
= SYMBOL_BLOCK_VALUE (func
);
7652 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7654 if (!SYMBOL_IS_ARGUMENT (sym
))
7661 insert_exception_resume_breakpoint (ecs
->event_thread
,
7667 CATCH (e
, RETURN_MASK_ERROR
)
7674 stop_waiting (struct execution_control_state
*ecs
)
7677 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7679 clear_step_over_info ();
7681 /* Let callers know we don't want to wait for the inferior anymore. */
7682 ecs
->wait_some_more
= 0;
7684 /* If all-stop, but the target is always in non-stop mode, stop all
7685 threads now that we're presenting the stop to the user. */
7686 if (!non_stop
&& target_is_non_stop_p ())
7687 stop_all_threads ();
7690 /* Like keep_going, but passes the signal to the inferior, even if the
7691 signal is set to nopass. */
7694 keep_going_pass_signal (struct execution_control_state
*ecs
)
7696 /* Make sure normal_stop is called if we get a QUIT handled before
7698 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
7700 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7701 gdb_assert (!ecs
->event_thread
->resumed
);
7703 /* Save the pc before execution, to compare with pc after stop. */
7704 ecs
->event_thread
->prev_pc
7705 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7707 if (ecs
->event_thread
->control
.trap_expected
)
7709 struct thread_info
*tp
= ecs
->event_thread
;
7712 fprintf_unfiltered (gdb_stdlog
,
7713 "infrun: %s has trap_expected set, "
7714 "resuming to collect trap\n",
7715 target_pid_to_str (tp
->ptid
));
7717 /* We haven't yet gotten our trap, and either: intercepted a
7718 non-signal event (e.g., a fork); or took a signal which we
7719 are supposed to pass through to the inferior. Simply
7721 discard_cleanups (old_cleanups
);
7722 resume (ecs
->event_thread
->suspend
.stop_signal
);
7724 else if (step_over_info_valid_p ())
7726 /* Another thread is stepping over a breakpoint in-line. If
7727 this thread needs a step-over too, queue the request. In
7728 either case, this resume must be deferred for later. */
7729 struct thread_info
*tp
= ecs
->event_thread
;
7731 if (ecs
->hit_singlestep_breakpoint
7732 || thread_still_needs_step_over (tp
))
7735 fprintf_unfiltered (gdb_stdlog
,
7736 "infrun: step-over already in progress: "
7737 "step-over for %s deferred\n",
7738 target_pid_to_str (tp
->ptid
));
7739 thread_step_over_chain_enqueue (tp
);
7744 fprintf_unfiltered (gdb_stdlog
,
7745 "infrun: step-over in progress: "
7746 "resume of %s deferred\n",
7747 target_pid_to_str (tp
->ptid
));
7750 discard_cleanups (old_cleanups
);
7754 struct regcache
*regcache
= get_current_regcache ();
7757 step_over_what step_what
;
7759 /* Either the trap was not expected, but we are continuing
7760 anyway (if we got a signal, the user asked it be passed to
7763 We got our expected trap, but decided we should resume from
7766 We're going to run this baby now!
7768 Note that insert_breakpoints won't try to re-insert
7769 already inserted breakpoints. Therefore, we don't
7770 care if breakpoints were already inserted, or not. */
7772 /* If we need to step over a breakpoint, and we're not using
7773 displaced stepping to do so, insert all breakpoints
7774 (watchpoints, etc.) but the one we're stepping over, step one
7775 instruction, and then re-insert the breakpoint when that step
7778 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7780 remove_bp
= (ecs
->hit_singlestep_breakpoint
7781 || (step_what
& STEP_OVER_BREAKPOINT
));
7782 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7784 /* We can't use displaced stepping if we need to step past a
7785 watchpoint. The instruction copied to the scratch pad would
7786 still trigger the watchpoint. */
7788 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7790 set_step_over_info (get_regcache_aspace (regcache
),
7791 regcache_read_pc (regcache
), remove_wps
,
7792 ecs
->event_thread
->global_num
);
7794 else if (remove_wps
)
7795 set_step_over_info (NULL
, 0, remove_wps
, -1);
7797 /* If we now need to do an in-line step-over, we need to stop
7798 all other threads. Note this must be done before
7799 insert_breakpoints below, because that removes the breakpoint
7800 we're about to step over, otherwise other threads could miss
7802 if (step_over_info_valid_p () && target_is_non_stop_p ())
7803 stop_all_threads ();
7805 /* Stop stepping if inserting breakpoints fails. */
7808 insert_breakpoints ();
7810 CATCH (e
, RETURN_MASK_ERROR
)
7812 exception_print (gdb_stderr
, e
);
7814 discard_cleanups (old_cleanups
);
7819 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7821 discard_cleanups (old_cleanups
);
7822 resume (ecs
->event_thread
->suspend
.stop_signal
);
7825 prepare_to_wait (ecs
);
7828 /* Called when we should continue running the inferior, because the
7829 current event doesn't cause a user visible stop. This does the
7830 resuming part; waiting for the next event is done elsewhere. */
7833 keep_going (struct execution_control_state
*ecs
)
7835 if (ecs
->event_thread
->control
.trap_expected
7836 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7837 ecs
->event_thread
->control
.trap_expected
= 0;
7839 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7840 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7841 keep_going_pass_signal (ecs
);
7844 /* This function normally comes after a resume, before
7845 handle_inferior_event exits. It takes care of any last bits of
7846 housekeeping, and sets the all-important wait_some_more flag. */
7849 prepare_to_wait (struct execution_control_state
*ecs
)
7852 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7854 ecs
->wait_some_more
= 1;
7856 if (!target_is_async_p ())
7857 mark_infrun_async_event_handler ();
7860 /* We are done with the step range of a step/next/si/ni command.
7861 Called once for each n of a "step n" operation. */
7864 end_stepping_range (struct execution_control_state
*ecs
)
7866 ecs
->event_thread
->control
.stop_step
= 1;
7870 /* Several print_*_reason functions to print why the inferior has stopped.
7871 We always print something when the inferior exits, or receives a signal.
7872 The rest of the cases are dealt with later on in normal_stop and
7873 print_it_typical. Ideally there should be a call to one of these
7874 print_*_reason functions functions from handle_inferior_event each time
7875 stop_waiting is called.
7877 Note that we don't call these directly, instead we delegate that to
7878 the interpreters, through observers. Interpreters then call these
7879 with whatever uiout is right. */
7882 print_end_stepping_range_reason (struct ui_out
*uiout
)
7884 /* For CLI-like interpreters, print nothing. */
7886 if (uiout
->is_mi_like_p ())
7888 uiout
->field_string ("reason",
7889 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7894 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7896 annotate_signalled ();
7897 if (uiout
->is_mi_like_p ())
7899 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7900 uiout
->text ("\nProgram terminated with signal ");
7901 annotate_signal_name ();
7902 uiout
->field_string ("signal-name",
7903 gdb_signal_to_name (siggnal
));
7904 annotate_signal_name_end ();
7906 annotate_signal_string ();
7907 uiout
->field_string ("signal-meaning",
7908 gdb_signal_to_string (siggnal
));
7909 annotate_signal_string_end ();
7910 uiout
->text (".\n");
7911 uiout
->text ("The program no longer exists.\n");
7915 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7917 struct inferior
*inf
= current_inferior ();
7918 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7920 annotate_exited (exitstatus
);
7923 if (uiout
->is_mi_like_p ())
7924 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
7925 uiout
->text ("[Inferior ");
7926 uiout
->text (plongest (inf
->num
));
7928 uiout
->text (pidstr
);
7929 uiout
->text (") exited with code ");
7930 uiout
->field_fmt ("exit-code", "0%o", (unsigned int) exitstatus
);
7931 uiout
->text ("]\n");
7935 if (uiout
->is_mi_like_p ())
7937 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7938 uiout
->text ("[Inferior ");
7939 uiout
->text (plongest (inf
->num
));
7941 uiout
->text (pidstr
);
7942 uiout
->text (") exited normally]\n");
7946 /* Some targets/architectures can do extra processing/display of
7947 segmentation faults. E.g., Intel MPX boundary faults.
7948 Call the architecture dependent function to handle the fault. */
7951 handle_segmentation_fault (struct ui_out
*uiout
)
7953 struct regcache
*regcache
= get_current_regcache ();
7954 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7956 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7957 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7961 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7963 struct thread_info
*thr
= inferior_thread ();
7967 if (uiout
->is_mi_like_p ())
7969 else if (show_thread_that_caused_stop ())
7973 uiout
->text ("\nThread ");
7974 uiout
->field_fmt ("thread-id", "%s", print_thread_id (thr
));
7976 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7979 uiout
->text (" \"");
7980 uiout
->field_fmt ("name", "%s", name
);
7985 uiout
->text ("\nProgram");
7987 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
7988 uiout
->text (" stopped");
7991 uiout
->text (" received signal ");
7992 annotate_signal_name ();
7993 if (uiout
->is_mi_like_p ())
7995 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
7996 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
7997 annotate_signal_name_end ();
7999 annotate_signal_string ();
8000 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
8002 if (siggnal
== GDB_SIGNAL_SEGV
)
8003 handle_segmentation_fault (uiout
);
8005 annotate_signal_string_end ();
8007 uiout
->text (".\n");
8011 print_no_history_reason (struct ui_out
*uiout
)
8013 uiout
->text ("\nNo more reverse-execution history.\n");
8016 /* Print current location without a level number, if we have changed
8017 functions or hit a breakpoint. Print source line if we have one.
8018 bpstat_print contains the logic deciding in detail what to print,
8019 based on the event(s) that just occurred. */
8022 print_stop_location (struct target_waitstatus
*ws
)
8025 enum print_what source_flag
;
8026 int do_frame_printing
= 1;
8027 struct thread_info
*tp
= inferior_thread ();
8029 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8033 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8034 should) carry around the function and does (or should) use
8035 that when doing a frame comparison. */
8036 if (tp
->control
.stop_step
8037 && frame_id_eq (tp
->control
.step_frame_id
,
8038 get_frame_id (get_current_frame ()))
8039 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
8041 /* Finished step, just print source line. */
8042 source_flag
= SRC_LINE
;
8046 /* Print location and source line. */
8047 source_flag
= SRC_AND_LOC
;
8050 case PRINT_SRC_AND_LOC
:
8051 /* Print location and source line. */
8052 source_flag
= SRC_AND_LOC
;
8054 case PRINT_SRC_ONLY
:
8055 source_flag
= SRC_LINE
;
8058 /* Something bogus. */
8059 source_flag
= SRC_LINE
;
8060 do_frame_printing
= 0;
8063 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8066 /* The behavior of this routine with respect to the source
8068 SRC_LINE: Print only source line
8069 LOCATION: Print only location
8070 SRC_AND_LOC: Print location and source line. */
8071 if (do_frame_printing
)
8072 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8078 print_stop_event (struct ui_out
*uiout
)
8080 struct target_waitstatus last
;
8082 struct thread_info
*tp
;
8084 get_last_target_status (&last_ptid
, &last
);
8087 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8089 print_stop_location (&last
);
8091 /* Display the auto-display expressions. */
8095 tp
= inferior_thread ();
8096 if (tp
->thread_fsm
!= NULL
8097 && thread_fsm_finished_p (tp
->thread_fsm
))
8099 struct return_value_info
*rv
;
8101 rv
= thread_fsm_return_value (tp
->thread_fsm
);
8103 print_return_value (uiout
, rv
);
8110 maybe_remove_breakpoints (void)
8112 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
8114 if (remove_breakpoints ())
8116 target_terminal_ours_for_output ();
8117 printf_filtered (_("Cannot remove breakpoints because "
8118 "program is no longer writable.\nFurther "
8119 "execution is probably impossible.\n"));
8124 /* The execution context that just caused a normal stop. */
8131 /* The event PTID. */
8135 /* If stopp for a thread event, this is the thread that caused the
8137 struct thread_info
*thread
;
8139 /* The inferior that caused the stop. */
8143 /* Returns a new stop context. If stopped for a thread event, this
8144 takes a strong reference to the thread. */
8146 static struct stop_context
*
8147 save_stop_context (void)
8149 struct stop_context
*sc
= XNEW (struct stop_context
);
8151 sc
->stop_id
= get_stop_id ();
8152 sc
->ptid
= inferior_ptid
;
8153 sc
->inf_num
= current_inferior ()->num
;
8155 if (!ptid_equal (inferior_ptid
, null_ptid
))
8157 /* Take a strong reference so that the thread can't be deleted
8159 sc
->thread
= inferior_thread ();
8160 sc
->thread
->refcount
++;
8168 /* Release a stop context previously created with save_stop_context.
8169 Releases the strong reference to the thread as well. */
8172 release_stop_context_cleanup (void *arg
)
8174 struct stop_context
*sc
= (struct stop_context
*) arg
;
8176 if (sc
->thread
!= NULL
)
8177 sc
->thread
->refcount
--;
8181 /* Return true if the current context no longer matches the saved stop
8185 stop_context_changed (struct stop_context
*prev
)
8187 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
8189 if (prev
->inf_num
!= current_inferior ()->num
)
8191 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
8193 if (get_stop_id () != prev
->stop_id
)
8203 struct target_waitstatus last
;
8205 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
8208 get_last_target_status (&last_ptid
, &last
);
8212 /* If an exception is thrown from this point on, make sure to
8213 propagate GDB's knowledge of the executing state to the
8214 frontend/user running state. A QUIT is an easy exception to see
8215 here, so do this before any filtered output. */
8217 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
8218 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8219 || last
.kind
== TARGET_WAITKIND_EXITED
)
8221 /* On some targets, we may still have live threads in the
8222 inferior when we get a process exit event. E.g., for
8223 "checkpoint", when the current checkpoint/fork exits,
8224 linux-fork.c automatically switches to another fork from
8225 within target_mourn_inferior. */
8226 if (!ptid_equal (inferior_ptid
, null_ptid
))
8228 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8229 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8232 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8233 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8235 /* As we're presenting a stop, and potentially removing breakpoints,
8236 update the thread list so we can tell whether there are threads
8237 running on the target. With target remote, for example, we can
8238 only learn about new threads when we explicitly update the thread
8239 list. Do this before notifying the interpreters about signal
8240 stops, end of stepping ranges, etc., so that the "new thread"
8241 output is emitted before e.g., "Program received signal FOO",
8242 instead of after. */
8243 update_thread_list ();
8245 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8246 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
8248 /* As with the notification of thread events, we want to delay
8249 notifying the user that we've switched thread context until
8250 the inferior actually stops.
8252 There's no point in saying anything if the inferior has exited.
8253 Note that SIGNALLED here means "exited with a signal", not
8254 "received a signal".
8256 Also skip saying anything in non-stop mode. In that mode, as we
8257 don't want GDB to switch threads behind the user's back, to avoid
8258 races where the user is typing a command to apply to thread x,
8259 but GDB switches to thread y before the user finishes entering
8260 the command, fetch_inferior_event installs a cleanup to restore
8261 the current thread back to the thread the user had selected right
8262 after this event is handled, so we're not really switching, only
8263 informing of a stop. */
8265 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8266 && target_has_execution
8267 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8268 && last
.kind
!= TARGET_WAITKIND_EXITED
8269 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8271 SWITCH_THRU_ALL_UIS ()
8273 target_terminal_ours_for_output ();
8274 printf_filtered (_("[Switching to %s]\n"),
8275 target_pid_to_str (inferior_ptid
));
8276 annotate_thread_changed ();
8278 previous_inferior_ptid
= inferior_ptid
;
8281 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8283 SWITCH_THRU_ALL_UIS ()
8284 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8286 target_terminal_ours_for_output ();
8287 printf_filtered (_("No unwaited-for children left.\n"));
8291 /* Note: this depends on the update_thread_list call above. */
8292 maybe_remove_breakpoints ();
8294 /* If an auto-display called a function and that got a signal,
8295 delete that auto-display to avoid an infinite recursion. */
8297 if (stopped_by_random_signal
)
8298 disable_current_display ();
8300 SWITCH_THRU_ALL_UIS ()
8302 async_enable_stdin ();
8305 /* Let the user/frontend see the threads as stopped. */
8306 do_cleanups (old_chain
);
8308 /* Select innermost stack frame - i.e., current frame is frame 0,
8309 and current location is based on that. Handle the case where the
8310 dummy call is returning after being stopped. E.g. the dummy call
8311 previously hit a breakpoint. (If the dummy call returns
8312 normally, we won't reach here.) Do this before the stop hook is
8313 run, so that it doesn't get to see the temporary dummy frame,
8314 which is not where we'll present the stop. */
8315 if (has_stack_frames ())
8317 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8319 /* Pop the empty frame that contains the stack dummy. This
8320 also restores inferior state prior to the call (struct
8321 infcall_suspend_state). */
8322 struct frame_info
*frame
= get_current_frame ();
8324 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8326 /* frame_pop calls reinit_frame_cache as the last thing it
8327 does which means there's now no selected frame. */
8330 select_frame (get_current_frame ());
8332 /* Set the current source location. */
8333 set_current_sal_from_frame (get_current_frame ());
8336 /* Look up the hook_stop and run it (CLI internally handles problem
8337 of stop_command's pre-hook not existing). */
8338 if (stop_command
!= NULL
)
8340 struct stop_context
*saved_context
= save_stop_context ();
8341 struct cleanup
*old_chain
8342 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8344 catch_errors (hook_stop_stub
, stop_command
,
8345 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
8347 /* If the stop hook resumes the target, then there's no point in
8348 trying to notify about the previous stop; its context is
8349 gone. Likewise if the command switches thread or inferior --
8350 the observers would print a stop for the wrong
8352 if (stop_context_changed (saved_context
))
8354 do_cleanups (old_chain
);
8357 do_cleanups (old_chain
);
8360 /* Notify observers about the stop. This is where the interpreters
8361 print the stop event. */
8362 if (!ptid_equal (inferior_ptid
, null_ptid
))
8363 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
8366 observer_notify_normal_stop (NULL
, stop_print_frame
);
8368 annotate_stopped ();
8370 if (target_has_execution
)
8372 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8373 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8374 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8375 Delete any breakpoint that is to be deleted at the next stop. */
8376 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8379 /* Try to get rid of automatically added inferiors that are no
8380 longer needed. Keeping those around slows down things linearly.
8381 Note that this never removes the current inferior. */
8388 hook_stop_stub (void *cmd
)
8390 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
8395 signal_stop_state (int signo
)
8397 return signal_stop
[signo
];
8401 signal_print_state (int signo
)
8403 return signal_print
[signo
];
8407 signal_pass_state (int signo
)
8409 return signal_program
[signo
];
8413 signal_cache_update (int signo
)
8417 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8418 signal_cache_update (signo
);
8423 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8424 && signal_print
[signo
] == 0
8425 && signal_program
[signo
] == 1
8426 && signal_catch
[signo
] == 0);
8430 signal_stop_update (int signo
, int state
)
8432 int ret
= signal_stop
[signo
];
8434 signal_stop
[signo
] = state
;
8435 signal_cache_update (signo
);
8440 signal_print_update (int signo
, int state
)
8442 int ret
= signal_print
[signo
];
8444 signal_print
[signo
] = state
;
8445 signal_cache_update (signo
);
8450 signal_pass_update (int signo
, int state
)
8452 int ret
= signal_program
[signo
];
8454 signal_program
[signo
] = state
;
8455 signal_cache_update (signo
);
8459 /* Update the global 'signal_catch' from INFO and notify the
8463 signal_catch_update (const unsigned int *info
)
8467 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8468 signal_catch
[i
] = info
[i
] > 0;
8469 signal_cache_update (-1);
8470 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8474 sig_print_header (void)
8476 printf_filtered (_("Signal Stop\tPrint\tPass "
8477 "to program\tDescription\n"));
8481 sig_print_info (enum gdb_signal oursig
)
8483 const char *name
= gdb_signal_to_name (oursig
);
8484 int name_padding
= 13 - strlen (name
);
8486 if (name_padding
<= 0)
8489 printf_filtered ("%s", name
);
8490 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8491 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8492 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8493 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8494 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8497 /* Specify how various signals in the inferior should be handled. */
8500 handle_command (char *args
, int from_tty
)
8503 int digits
, wordlen
;
8504 int sigfirst
, signum
, siglast
;
8505 enum gdb_signal oursig
;
8508 unsigned char *sigs
;
8509 struct cleanup
*old_chain
;
8513 error_no_arg (_("signal to handle"));
8516 /* Allocate and zero an array of flags for which signals to handle. */
8518 nsigs
= (int) GDB_SIGNAL_LAST
;
8519 sigs
= (unsigned char *) alloca (nsigs
);
8520 memset (sigs
, 0, nsigs
);
8522 /* Break the command line up into args. */
8524 argv
= gdb_buildargv (args
);
8525 old_chain
= make_cleanup_freeargv (argv
);
8527 /* Walk through the args, looking for signal oursigs, signal names, and
8528 actions. Signal numbers and signal names may be interspersed with
8529 actions, with the actions being performed for all signals cumulatively
8530 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8532 while (*argv
!= NULL
)
8534 wordlen
= strlen (*argv
);
8535 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
8539 sigfirst
= siglast
= -1;
8541 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
8543 /* Apply action to all signals except those used by the
8544 debugger. Silently skip those. */
8547 siglast
= nsigs
- 1;
8549 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
8551 SET_SIGS (nsigs
, sigs
, signal_stop
);
8552 SET_SIGS (nsigs
, sigs
, signal_print
);
8554 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
8556 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8558 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
8560 SET_SIGS (nsigs
, sigs
, signal_print
);
8562 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
8564 SET_SIGS (nsigs
, sigs
, signal_program
);
8566 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
8568 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8570 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
8572 SET_SIGS (nsigs
, sigs
, signal_program
);
8574 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
8576 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8577 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8579 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
8581 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8583 else if (digits
> 0)
8585 /* It is numeric. The numeric signal refers to our own
8586 internal signal numbering from target.h, not to host/target
8587 signal number. This is a feature; users really should be
8588 using symbolic names anyway, and the common ones like
8589 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8591 sigfirst
= siglast
= (int)
8592 gdb_signal_from_command (atoi (*argv
));
8593 if ((*argv
)[digits
] == '-')
8596 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
8598 if (sigfirst
> siglast
)
8600 /* Bet he didn't figure we'd think of this case... */
8608 oursig
= gdb_signal_from_name (*argv
);
8609 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8611 sigfirst
= siglast
= (int) oursig
;
8615 /* Not a number and not a recognized flag word => complain. */
8616 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
8620 /* If any signal numbers or symbol names were found, set flags for
8621 which signals to apply actions to. */
8623 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8625 switch ((enum gdb_signal
) signum
)
8627 case GDB_SIGNAL_TRAP
:
8628 case GDB_SIGNAL_INT
:
8629 if (!allsigs
&& !sigs
[signum
])
8631 if (query (_("%s is used by the debugger.\n\
8632 Are you sure you want to change it? "),
8633 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8639 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8640 gdb_flush (gdb_stdout
);
8645 case GDB_SIGNAL_DEFAULT
:
8646 case GDB_SIGNAL_UNKNOWN
:
8647 /* Make sure that "all" doesn't print these. */
8658 for (signum
= 0; signum
< nsigs
; signum
++)
8661 signal_cache_update (-1);
8662 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8663 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8667 /* Show the results. */
8668 sig_print_header ();
8669 for (; signum
< nsigs
; signum
++)
8671 sig_print_info ((enum gdb_signal
) signum
);
8677 do_cleanups (old_chain
);
8680 /* Complete the "handle" command. */
8682 static VEC (char_ptr
) *
8683 handle_completer (struct cmd_list_element
*ignore
,
8684 const char *text
, const char *word
)
8686 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
8687 static const char * const keywords
[] =
8701 vec_signals
= signal_completer (ignore
, text
, word
);
8702 vec_keywords
= complete_on_enum (keywords
, word
, word
);
8704 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
8705 VEC_free (char_ptr
, vec_signals
);
8706 VEC_free (char_ptr
, vec_keywords
);
8711 gdb_signal_from_command (int num
)
8713 if (num
>= 1 && num
<= 15)
8714 return (enum gdb_signal
) num
;
8715 error (_("Only signals 1-15 are valid as numeric signals.\n\
8716 Use \"info signals\" for a list of symbolic signals."));
8719 /* Print current contents of the tables set by the handle command.
8720 It is possible we should just be printing signals actually used
8721 by the current target (but for things to work right when switching
8722 targets, all signals should be in the signal tables). */
8725 signals_info (char *signum_exp
, int from_tty
)
8727 enum gdb_signal oursig
;
8729 sig_print_header ();
8733 /* First see if this is a symbol name. */
8734 oursig
= gdb_signal_from_name (signum_exp
);
8735 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8737 /* No, try numeric. */
8739 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8741 sig_print_info (oursig
);
8745 printf_filtered ("\n");
8746 /* These ugly casts brought to you by the native VAX compiler. */
8747 for (oursig
= GDB_SIGNAL_FIRST
;
8748 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8749 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8753 if (oursig
!= GDB_SIGNAL_UNKNOWN
8754 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8755 sig_print_info (oursig
);
8758 printf_filtered (_("\nUse the \"handle\" command "
8759 "to change these tables.\n"));
8762 /* The $_siginfo convenience variable is a bit special. We don't know
8763 for sure the type of the value until we actually have a chance to
8764 fetch the data. The type can change depending on gdbarch, so it is
8765 also dependent on which thread you have selected.
8767 1. making $_siginfo be an internalvar that creates a new value on
8770 2. making the value of $_siginfo be an lval_computed value. */
8772 /* This function implements the lval_computed support for reading a
8776 siginfo_value_read (struct value
*v
)
8778 LONGEST transferred
;
8780 /* If we can access registers, so can we access $_siginfo. Likewise
8782 validate_registers_access ();
8785 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8787 value_contents_all_raw (v
),
8789 TYPE_LENGTH (value_type (v
)));
8791 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8792 error (_("Unable to read siginfo"));
8795 /* This function implements the lval_computed support for writing a
8799 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8801 LONGEST transferred
;
8803 /* If we can access registers, so can we access $_siginfo. Likewise
8805 validate_registers_access ();
8807 transferred
= target_write (¤t_target
,
8808 TARGET_OBJECT_SIGNAL_INFO
,
8810 value_contents_all_raw (fromval
),
8812 TYPE_LENGTH (value_type (fromval
)));
8814 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8815 error (_("Unable to write siginfo"));
8818 static const struct lval_funcs siginfo_value_funcs
=
8824 /* Return a new value with the correct type for the siginfo object of
8825 the current thread using architecture GDBARCH. Return a void value
8826 if there's no object available. */
8828 static struct value
*
8829 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8832 if (target_has_stack
8833 && !ptid_equal (inferior_ptid
, null_ptid
)
8834 && gdbarch_get_siginfo_type_p (gdbarch
))
8836 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8838 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8841 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8845 /* infcall_suspend_state contains state about the program itself like its
8846 registers and any signal it received when it last stopped.
8847 This state must be restored regardless of how the inferior function call
8848 ends (either successfully, or after it hits a breakpoint or signal)
8849 if the program is to properly continue where it left off. */
8851 struct infcall_suspend_state
8853 struct thread_suspend_state thread_suspend
;
8857 struct regcache
*registers
;
8859 /* Format of SIGINFO_DATA or NULL if it is not present. */
8860 struct gdbarch
*siginfo_gdbarch
;
8862 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8863 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8864 content would be invalid. */
8865 gdb_byte
*siginfo_data
;
8868 struct infcall_suspend_state
*
8869 save_infcall_suspend_state (void)
8871 struct infcall_suspend_state
*inf_state
;
8872 struct thread_info
*tp
= inferior_thread ();
8873 struct regcache
*regcache
= get_current_regcache ();
8874 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8875 gdb_byte
*siginfo_data
= NULL
;
8877 if (gdbarch_get_siginfo_type_p (gdbarch
))
8879 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8880 size_t len
= TYPE_LENGTH (type
);
8881 struct cleanup
*back_to
;
8883 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8884 back_to
= make_cleanup (xfree
, siginfo_data
);
8886 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8887 siginfo_data
, 0, len
) == len
)
8888 discard_cleanups (back_to
);
8891 /* Errors ignored. */
8892 do_cleanups (back_to
);
8893 siginfo_data
= NULL
;
8897 inf_state
= XCNEW (struct infcall_suspend_state
);
8901 inf_state
->siginfo_gdbarch
= gdbarch
;
8902 inf_state
->siginfo_data
= siginfo_data
;
8905 inf_state
->thread_suspend
= tp
->suspend
;
8907 /* run_inferior_call will not use the signal due to its `proceed' call with
8908 GDB_SIGNAL_0 anyway. */
8909 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8911 inf_state
->stop_pc
= stop_pc
;
8913 inf_state
->registers
= regcache_dup (regcache
);
8918 /* Restore inferior session state to INF_STATE. */
8921 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8923 struct thread_info
*tp
= inferior_thread ();
8924 struct regcache
*regcache
= get_current_regcache ();
8925 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8927 tp
->suspend
= inf_state
->thread_suspend
;
8929 stop_pc
= inf_state
->stop_pc
;
8931 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8933 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8935 /* Errors ignored. */
8936 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8937 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8940 /* The inferior can be gone if the user types "print exit(0)"
8941 (and perhaps other times). */
8942 if (target_has_execution
)
8943 /* NB: The register write goes through to the target. */
8944 regcache_cpy (regcache
, inf_state
->registers
);
8946 discard_infcall_suspend_state (inf_state
);
8950 do_restore_infcall_suspend_state_cleanup (void *state
)
8952 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
8956 make_cleanup_restore_infcall_suspend_state
8957 (struct infcall_suspend_state
*inf_state
)
8959 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8963 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8965 regcache_xfree (inf_state
->registers
);
8966 xfree (inf_state
->siginfo_data
);
8971 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8973 return inf_state
->registers
;
8976 /* infcall_control_state contains state regarding gdb's control of the
8977 inferior itself like stepping control. It also contains session state like
8978 the user's currently selected frame. */
8980 struct infcall_control_state
8982 struct thread_control_state thread_control
;
8983 struct inferior_control_state inferior_control
;
8986 enum stop_stack_kind stop_stack_dummy
;
8987 int stopped_by_random_signal
;
8989 /* ID if the selected frame when the inferior function call was made. */
8990 struct frame_id selected_frame_id
;
8993 /* Save all of the information associated with the inferior<==>gdb
8996 struct infcall_control_state
*
8997 save_infcall_control_state (void)
8999 struct infcall_control_state
*inf_status
=
9000 XNEW (struct infcall_control_state
);
9001 struct thread_info
*tp
= inferior_thread ();
9002 struct inferior
*inf
= current_inferior ();
9004 inf_status
->thread_control
= tp
->control
;
9005 inf_status
->inferior_control
= inf
->control
;
9007 tp
->control
.step_resume_breakpoint
= NULL
;
9008 tp
->control
.exception_resume_breakpoint
= NULL
;
9010 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9011 chain. If caller's caller is walking the chain, they'll be happier if we
9012 hand them back the original chain when restore_infcall_control_state is
9014 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9017 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9018 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9020 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
9026 restore_selected_frame (void *args
)
9028 struct frame_id
*fid
= (struct frame_id
*) args
;
9029 struct frame_info
*frame
;
9031 frame
= frame_find_by_id (*fid
);
9033 /* If inf_status->selected_frame_id is NULL, there was no previously
9037 warning (_("Unable to restore previously selected frame."));
9041 select_frame (frame
);
9046 /* Restore inferior session state to INF_STATUS. */
9049 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9051 struct thread_info
*tp
= inferior_thread ();
9052 struct inferior
*inf
= current_inferior ();
9054 if (tp
->control
.step_resume_breakpoint
)
9055 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9057 if (tp
->control
.exception_resume_breakpoint
)
9058 tp
->control
.exception_resume_breakpoint
->disposition
9059 = disp_del_at_next_stop
;
9061 /* Handle the bpstat_copy of the chain. */
9062 bpstat_clear (&tp
->control
.stop_bpstat
);
9064 tp
->control
= inf_status
->thread_control
;
9065 inf
->control
= inf_status
->inferior_control
;
9068 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9069 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9071 if (target_has_stack
)
9073 /* The point of catch_errors is that if the stack is clobbered,
9074 walking the stack might encounter a garbage pointer and
9075 error() trying to dereference it. */
9077 (restore_selected_frame
, &inf_status
->selected_frame_id
,
9078 "Unable to restore previously selected frame:\n",
9079 RETURN_MASK_ERROR
) == 0)
9080 /* Error in restoring the selected frame. Select the innermost
9082 select_frame (get_current_frame ());
9089 do_restore_infcall_control_state_cleanup (void *sts
)
9091 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
9095 make_cleanup_restore_infcall_control_state
9096 (struct infcall_control_state
*inf_status
)
9098 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
9102 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9104 if (inf_status
->thread_control
.step_resume_breakpoint
)
9105 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9106 = disp_del_at_next_stop
;
9108 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9109 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9110 = disp_del_at_next_stop
;
9112 /* See save_infcall_control_state for info on stop_bpstat. */
9113 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9118 /* restore_inferior_ptid() will be used by the cleanup machinery
9119 to restore the inferior_ptid value saved in a call to
9120 save_inferior_ptid(). */
9123 restore_inferior_ptid (void *arg
)
9125 ptid_t
*saved_ptid_ptr
= (ptid_t
*) arg
;
9127 inferior_ptid
= *saved_ptid_ptr
;
9131 /* Save the value of inferior_ptid so that it may be restored by a
9132 later call to do_cleanups(). Returns the struct cleanup pointer
9133 needed for later doing the cleanup. */
9136 save_inferior_ptid (void)
9138 ptid_t
*saved_ptid_ptr
= XNEW (ptid_t
);
9140 *saved_ptid_ptr
= inferior_ptid
;
9141 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
9147 clear_exit_convenience_vars (void)
9149 clear_internalvar (lookup_internalvar ("_exitsignal"));
9150 clear_internalvar (lookup_internalvar ("_exitcode"));
9154 /* User interface for reverse debugging:
9155 Set exec-direction / show exec-direction commands
9156 (returns error unless target implements to_set_exec_direction method). */
9158 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9159 static const char exec_forward
[] = "forward";
9160 static const char exec_reverse
[] = "reverse";
9161 static const char *exec_direction
= exec_forward
;
9162 static const char *const exec_direction_names
[] = {
9169 set_exec_direction_func (char *args
, int from_tty
,
9170 struct cmd_list_element
*cmd
)
9172 if (target_can_execute_reverse
)
9174 if (!strcmp (exec_direction
, exec_forward
))
9175 execution_direction
= EXEC_FORWARD
;
9176 else if (!strcmp (exec_direction
, exec_reverse
))
9177 execution_direction
= EXEC_REVERSE
;
9181 exec_direction
= exec_forward
;
9182 error (_("Target does not support this operation."));
9187 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9188 struct cmd_list_element
*cmd
, const char *value
)
9190 switch (execution_direction
) {
9192 fprintf_filtered (out
, _("Forward.\n"));
9195 fprintf_filtered (out
, _("Reverse.\n"));
9198 internal_error (__FILE__
, __LINE__
,
9199 _("bogus execution_direction value: %d"),
9200 (int) execution_direction
);
9205 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9206 struct cmd_list_element
*c
, const char *value
)
9208 fprintf_filtered (file
, _("Resuming the execution of threads "
9209 "of all processes is %s.\n"), value
);
9212 /* Implementation of `siginfo' variable. */
9214 static const struct internalvar_funcs siginfo_funcs
=
9221 /* Callback for infrun's target events source. This is marked when a
9222 thread has a pending status to process. */
9225 infrun_async_inferior_event_handler (gdb_client_data data
)
9227 inferior_event_handler (INF_REG_EVENT
, NULL
);
9231 _initialize_infrun (void)
9235 struct cmd_list_element
*c
;
9237 /* Register extra event sources in the event loop. */
9238 infrun_async_inferior_event_token
9239 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9241 add_info ("signals", signals_info
, _("\
9242 What debugger does when program gets various signals.\n\
9243 Specify a signal as argument to print info on that signal only."));
9244 add_info_alias ("handle", "signals", 0);
9246 c
= add_com ("handle", class_run
, handle_command
, _("\
9247 Specify how to handle signals.\n\
9248 Usage: handle SIGNAL [ACTIONS]\n\
9249 Args are signals and actions to apply to those signals.\n\
9250 If no actions are specified, the current settings for the specified signals\n\
9251 will be displayed instead.\n\
9253 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9254 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9255 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9256 The special arg \"all\" is recognized to mean all signals except those\n\
9257 used by the debugger, typically SIGTRAP and SIGINT.\n\
9259 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9260 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9261 Stop means reenter debugger if this signal happens (implies print).\n\
9262 Print means print a message if this signal happens.\n\
9263 Pass means let program see this signal; otherwise program doesn't know.\n\
9264 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9265 Pass and Stop may be combined.\n\
9267 Multiple signals may be specified. Signal numbers and signal names\n\
9268 may be interspersed with actions, with the actions being performed for\n\
9269 all signals cumulatively specified."));
9270 set_cmd_completer (c
, handle_completer
);
9273 stop_command
= add_cmd ("stop", class_obscure
,
9274 not_just_help_class_command
, _("\
9275 There is no `stop' command, but you can set a hook on `stop'.\n\
9276 This allows you to set a list of commands to be run each time execution\n\
9277 of the program stops."), &cmdlist
);
9279 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9280 Set inferior debugging."), _("\
9281 Show inferior debugging."), _("\
9282 When non-zero, inferior specific debugging is enabled."),
9285 &setdebuglist
, &showdebuglist
);
9287 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9288 &debug_displaced
, _("\
9289 Set displaced stepping debugging."), _("\
9290 Show displaced stepping debugging."), _("\
9291 When non-zero, displaced stepping specific debugging is enabled."),
9293 show_debug_displaced
,
9294 &setdebuglist
, &showdebuglist
);
9296 add_setshow_boolean_cmd ("non-stop", no_class
,
9298 Set whether gdb controls the inferior in non-stop mode."), _("\
9299 Show whether gdb controls the inferior in non-stop mode."), _("\
9300 When debugging a multi-threaded program and this setting is\n\
9301 off (the default, also called all-stop mode), when one thread stops\n\
9302 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9303 all other threads in the program while you interact with the thread of\n\
9304 interest. When you continue or step a thread, you can allow the other\n\
9305 threads to run, or have them remain stopped, but while you inspect any\n\
9306 thread's state, all threads stop.\n\
9308 In non-stop mode, when one thread stops, other threads can continue\n\
9309 to run freely. You'll be able to step each thread independently,\n\
9310 leave it stopped or free to run as needed."),
9316 numsigs
= (int) GDB_SIGNAL_LAST
;
9317 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9318 signal_print
= XNEWVEC (unsigned char, numsigs
);
9319 signal_program
= XNEWVEC (unsigned char, numsigs
);
9320 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9321 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9322 for (i
= 0; i
< numsigs
; i
++)
9325 signal_print
[i
] = 1;
9326 signal_program
[i
] = 1;
9327 signal_catch
[i
] = 0;
9330 /* Signals caused by debugger's own actions should not be given to
9331 the program afterwards.
9333 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9334 explicitly specifies that it should be delivered to the target
9335 program. Typically, that would occur when a user is debugging a
9336 target monitor on a simulator: the target monitor sets a
9337 breakpoint; the simulator encounters this breakpoint and halts
9338 the simulation handing control to GDB; GDB, noting that the stop
9339 address doesn't map to any known breakpoint, returns control back
9340 to the simulator; the simulator then delivers the hardware
9341 equivalent of a GDB_SIGNAL_TRAP to the program being
9343 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9344 signal_program
[GDB_SIGNAL_INT
] = 0;
9346 /* Signals that are not errors should not normally enter the debugger. */
9347 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9348 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9349 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9350 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9351 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9352 signal_print
[GDB_SIGNAL_PROF
] = 0;
9353 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9354 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9355 signal_stop
[GDB_SIGNAL_IO
] = 0;
9356 signal_print
[GDB_SIGNAL_IO
] = 0;
9357 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9358 signal_print
[GDB_SIGNAL_POLL
] = 0;
9359 signal_stop
[GDB_SIGNAL_URG
] = 0;
9360 signal_print
[GDB_SIGNAL_URG
] = 0;
9361 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9362 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9363 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9364 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9366 /* These signals are used internally by user-level thread
9367 implementations. (See signal(5) on Solaris.) Like the above
9368 signals, a healthy program receives and handles them as part of
9369 its normal operation. */
9370 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9371 signal_print
[GDB_SIGNAL_LWP
] = 0;
9372 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9373 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9374 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9375 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9376 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9377 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9379 /* Update cached state. */
9380 signal_cache_update (-1);
9382 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9383 &stop_on_solib_events
, _("\
9384 Set stopping for shared library events."), _("\
9385 Show stopping for shared library events."), _("\
9386 If nonzero, gdb will give control to the user when the dynamic linker\n\
9387 notifies gdb of shared library events. The most common event of interest\n\
9388 to the user would be loading/unloading of a new library."),
9389 set_stop_on_solib_events
,
9390 show_stop_on_solib_events
,
9391 &setlist
, &showlist
);
9393 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9394 follow_fork_mode_kind_names
,
9395 &follow_fork_mode_string
, _("\
9396 Set debugger response to a program call of fork or vfork."), _("\
9397 Show debugger response to a program call of fork or vfork."), _("\
9398 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9399 parent - the original process is debugged after a fork\n\
9400 child - the new process is debugged after a fork\n\
9401 The unfollowed process will continue to run.\n\
9402 By default, the debugger will follow the parent process."),
9404 show_follow_fork_mode_string
,
9405 &setlist
, &showlist
);
9407 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9408 follow_exec_mode_names
,
9409 &follow_exec_mode_string
, _("\
9410 Set debugger response to a program call of exec."), _("\
9411 Show debugger response to a program call of exec."), _("\
9412 An exec call replaces the program image of a process.\n\
9414 follow-exec-mode can be:\n\
9416 new - the debugger creates a new inferior and rebinds the process\n\
9417 to this new inferior. The program the process was running before\n\
9418 the exec call can be restarted afterwards by restarting the original\n\
9421 same - the debugger keeps the process bound to the same inferior.\n\
9422 The new executable image replaces the previous executable loaded in\n\
9423 the inferior. Restarting the inferior after the exec call restarts\n\
9424 the executable the process was running after the exec call.\n\
9426 By default, the debugger will use the same inferior."),
9428 show_follow_exec_mode_string
,
9429 &setlist
, &showlist
);
9431 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9432 scheduler_enums
, &scheduler_mode
, _("\
9433 Set mode for locking scheduler during execution."), _("\
9434 Show mode for locking scheduler during execution."), _("\
9435 off == no locking (threads may preempt at any time)\n\
9436 on == full locking (no thread except the current thread may run)\n\
9437 This applies to both normal execution and replay mode.\n\
9438 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9439 In this mode, other threads may run during other commands.\n\
9440 This applies to both normal execution and replay mode.\n\
9441 replay == scheduler locked in replay mode and unlocked during normal execution."),
9442 set_schedlock_func
, /* traps on target vector */
9443 show_scheduler_mode
,
9444 &setlist
, &showlist
);
9446 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9447 Set mode for resuming threads of all processes."), _("\
9448 Show mode for resuming threads of all processes."), _("\
9449 When on, execution commands (such as 'continue' or 'next') resume all\n\
9450 threads of all processes. When off (which is the default), execution\n\
9451 commands only resume the threads of the current process. The set of\n\
9452 threads that are resumed is further refined by the scheduler-locking\n\
9453 mode (see help set scheduler-locking)."),
9455 show_schedule_multiple
,
9456 &setlist
, &showlist
);
9458 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9459 Set mode of the step operation."), _("\
9460 Show mode of the step operation."), _("\
9461 When set, doing a step over a function without debug line information\n\
9462 will stop at the first instruction of that function. Otherwise, the\n\
9463 function is skipped and the step command stops at a different source line."),
9465 show_step_stop_if_no_debug
,
9466 &setlist
, &showlist
);
9468 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9469 &can_use_displaced_stepping
, _("\
9470 Set debugger's willingness to use displaced stepping."), _("\
9471 Show debugger's willingness to use displaced stepping."), _("\
9472 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9473 supported by the target architecture. If off, gdb will not use displaced\n\
9474 stepping to step over breakpoints, even if such is supported by the target\n\
9475 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9476 if the target architecture supports it and non-stop mode is active, but will not\n\
9477 use it in all-stop mode (see help set non-stop)."),
9479 show_can_use_displaced_stepping
,
9480 &setlist
, &showlist
);
9482 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9483 &exec_direction
, _("Set direction of execution.\n\
9484 Options are 'forward' or 'reverse'."),
9485 _("Show direction of execution (forward/reverse)."),
9486 _("Tells gdb whether to execute forward or backward."),
9487 set_exec_direction_func
, show_exec_direction_func
,
9488 &setlist
, &showlist
);
9490 /* Set/show detach-on-fork: user-settable mode. */
9492 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9493 Set whether gdb will detach the child of a fork."), _("\
9494 Show whether gdb will detach the child of a fork."), _("\
9495 Tells gdb whether to detach the child of a fork."),
9496 NULL
, NULL
, &setlist
, &showlist
);
9498 /* Set/show disable address space randomization mode. */
9500 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9501 &disable_randomization
, _("\
9502 Set disabling of debuggee's virtual address space randomization."), _("\
9503 Show disabling of debuggee's virtual address space randomization."), _("\
9504 When this mode is on (which is the default), randomization of the virtual\n\
9505 address space is disabled. Standalone programs run with the randomization\n\
9506 enabled by default on some platforms."),
9507 &set_disable_randomization
,
9508 &show_disable_randomization
,
9509 &setlist
, &showlist
);
9511 /* ptid initializations */
9512 inferior_ptid
= null_ptid
;
9513 target_last_wait_ptid
= minus_one_ptid
;
9515 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9516 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9517 observer_attach_thread_exit (infrun_thread_thread_exit
);
9518 observer_attach_inferior_exit (infrun_inferior_exit
);
9520 /* Explicitly create without lookup, since that tries to create a
9521 value with a void typed value, and when we get here, gdbarch
9522 isn't initialized yet. At this point, we're quite sure there
9523 isn't another convenience variable of the same name. */
9524 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9526 add_setshow_boolean_cmd ("observer", no_class
,
9527 &observer_mode_1
, _("\
9528 Set whether gdb controls the inferior in observer mode."), _("\
9529 Show whether gdb controls the inferior in observer mode."), _("\
9530 In observer mode, GDB can get data from the inferior, but not\n\
9531 affect its execution. Registers and memory may not be changed,\n\
9532 breakpoints may not be set, and the program cannot be interrupted\n\