1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2016 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 #include "event-loop.h"
65 #include "thread-fsm.h"
66 #include "common/enum-flags.h"
68 /* Prototypes for local functions */
70 static void signals_info (char *, int);
72 static void handle_command (char *, int);
74 static void sig_print_info (enum gdb_signal
);
76 static void sig_print_header (void);
78 static void resume_cleanups (void *);
80 static int hook_stop_stub (void *);
82 static int restore_selected_frame (void *);
84 static int follow_fork (void);
86 static int follow_fork_inferior (int follow_child
, int detach_fork
);
88 static void follow_inferior_reset_breakpoints (void);
90 static void set_schedlock_func (char *args
, int from_tty
,
91 struct cmd_list_element
*c
);
93 static int currently_stepping (struct thread_info
*tp
);
95 void _initialize_infrun (void);
97 void nullify_last_target_wait_ptid (void);
99 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
101 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
103 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
105 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
107 /* Asynchronous signal handler registered as event loop source for
108 when we have pending events ready to be passed to the core. */
109 static struct async_event_handler
*infrun_async_inferior_event_token
;
111 /* Stores whether infrun_async was previously enabled or disabled.
112 Starts off as -1, indicating "never enabled/disabled". */
113 static int infrun_is_async
= -1;
118 infrun_async (int enable
)
120 if (infrun_is_async
!= enable
)
122 infrun_is_async
= enable
;
125 fprintf_unfiltered (gdb_stdlog
,
126 "infrun: infrun_async(%d)\n",
130 mark_async_event_handler (infrun_async_inferior_event_token
);
132 clear_async_event_handler (infrun_async_inferior_event_token
);
139 mark_infrun_async_event_handler (void)
141 mark_async_event_handler (infrun_async_inferior_event_token
);
144 /* When set, stop the 'step' command if we enter a function which has
145 no line number information. The normal behavior is that we step
146 over such function. */
147 int step_stop_if_no_debug
= 0;
149 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
150 struct cmd_list_element
*c
, const char *value
)
152 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
155 /* proceed and normal_stop use this to notify the user when the
156 inferior stopped in a different thread than it had been running
159 static ptid_t previous_inferior_ptid
;
161 /* If set (default for legacy reasons), when following a fork, GDB
162 will detach from one of the fork branches, child or parent.
163 Exactly which branch is detached depends on 'set follow-fork-mode'
166 static int detach_fork
= 1;
168 int debug_displaced
= 0;
170 show_debug_displaced (struct ui_file
*file
, int from_tty
,
171 struct cmd_list_element
*c
, const char *value
)
173 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
176 unsigned int debug_infrun
= 0;
178 show_debug_infrun (struct ui_file
*file
, int from_tty
,
179 struct cmd_list_element
*c
, const char *value
)
181 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
185 /* Support for disabling address space randomization. */
187 int disable_randomization
= 1;
190 show_disable_randomization (struct ui_file
*file
, int from_tty
,
191 struct cmd_list_element
*c
, const char *value
)
193 if (target_supports_disable_randomization ())
194 fprintf_filtered (file
,
195 _("Disabling randomization of debuggee's "
196 "virtual address space is %s.\n"),
199 fputs_filtered (_("Disabling randomization of debuggee's "
200 "virtual address space is unsupported on\n"
201 "this platform.\n"), file
);
205 set_disable_randomization (char *args
, int from_tty
,
206 struct cmd_list_element
*c
)
208 if (!target_supports_disable_randomization ())
209 error (_("Disabling randomization of debuggee's "
210 "virtual address space is unsupported on\n"
214 /* User interface for non-stop mode. */
217 static int non_stop_1
= 0;
220 set_non_stop (char *args
, int from_tty
,
221 struct cmd_list_element
*c
)
223 if (target_has_execution
)
225 non_stop_1
= non_stop
;
226 error (_("Cannot change this setting while the inferior is running."));
229 non_stop
= non_stop_1
;
233 show_non_stop (struct ui_file
*file
, int from_tty
,
234 struct cmd_list_element
*c
, const char *value
)
236 fprintf_filtered (file
,
237 _("Controlling the inferior in non-stop mode is %s.\n"),
241 /* "Observer mode" is somewhat like a more extreme version of
242 non-stop, in which all GDB operations that might affect the
243 target's execution have been disabled. */
245 int observer_mode
= 0;
246 static int observer_mode_1
= 0;
249 set_observer_mode (char *args
, int from_tty
,
250 struct cmd_list_element
*c
)
252 if (target_has_execution
)
254 observer_mode_1
= observer_mode
;
255 error (_("Cannot change this setting while the inferior is running."));
258 observer_mode
= observer_mode_1
;
260 may_write_registers
= !observer_mode
;
261 may_write_memory
= !observer_mode
;
262 may_insert_breakpoints
= !observer_mode
;
263 may_insert_tracepoints
= !observer_mode
;
264 /* We can insert fast tracepoints in or out of observer mode,
265 but enable them if we're going into this mode. */
267 may_insert_fast_tracepoints
= 1;
268 may_stop
= !observer_mode
;
269 update_target_permissions ();
271 /* Going *into* observer mode we must force non-stop, then
272 going out we leave it that way. */
275 pagination_enabled
= 0;
276 non_stop
= non_stop_1
= 1;
280 printf_filtered (_("Observer mode is now %s.\n"),
281 (observer_mode
? "on" : "off"));
285 show_observer_mode (struct ui_file
*file
, int from_tty
,
286 struct cmd_list_element
*c
, const char *value
)
288 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
291 /* This updates the value of observer mode based on changes in
292 permissions. Note that we are deliberately ignoring the values of
293 may-write-registers and may-write-memory, since the user may have
294 reason to enable these during a session, for instance to turn on a
295 debugging-related global. */
298 update_observer_mode (void)
302 newval
= (!may_insert_breakpoints
303 && !may_insert_tracepoints
304 && may_insert_fast_tracepoints
308 /* Let the user know if things change. */
309 if (newval
!= observer_mode
)
310 printf_filtered (_("Observer mode is now %s.\n"),
311 (newval
? "on" : "off"));
313 observer_mode
= observer_mode_1
= newval
;
316 /* Tables of how to react to signals; the user sets them. */
318 static unsigned char *signal_stop
;
319 static unsigned char *signal_print
;
320 static unsigned char *signal_program
;
322 /* Table of signals that are registered with "catch signal". A
323 non-zero entry indicates that the signal is caught by some "catch
324 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
326 static unsigned char *signal_catch
;
328 /* Table of signals that the target may silently handle.
329 This is automatically determined from the flags above,
330 and simply cached here. */
331 static unsigned char *signal_pass
;
333 #define SET_SIGS(nsigs,sigs,flags) \
335 int signum = (nsigs); \
336 while (signum-- > 0) \
337 if ((sigs)[signum]) \
338 (flags)[signum] = 1; \
341 #define UNSET_SIGS(nsigs,sigs,flags) \
343 int signum = (nsigs); \
344 while (signum-- > 0) \
345 if ((sigs)[signum]) \
346 (flags)[signum] = 0; \
349 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
350 this function is to avoid exporting `signal_program'. */
353 update_signals_program_target (void)
355 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
358 /* Value to pass to target_resume() to cause all threads to resume. */
360 #define RESUME_ALL minus_one_ptid
362 /* Command list pointer for the "stop" placeholder. */
364 static struct cmd_list_element
*stop_command
;
366 /* Nonzero if we want to give control to the user when we're notified
367 of shared library events by the dynamic linker. */
368 int stop_on_solib_events
;
370 /* Enable or disable optional shared library event breakpoints
371 as appropriate when the above flag is changed. */
374 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
376 update_solib_breakpoints ();
380 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
381 struct cmd_list_element
*c
, const char *value
)
383 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
387 /* Nonzero after stop if current stack frame should be printed. */
389 static int stop_print_frame
;
391 /* This is a cached copy of the pid/waitstatus of the last event
392 returned by target_wait()/deprecated_target_wait_hook(). This
393 information is returned by get_last_target_status(). */
394 static ptid_t target_last_wait_ptid
;
395 static struct target_waitstatus target_last_waitstatus
;
397 static void context_switch (ptid_t ptid
);
399 void init_thread_stepping_state (struct thread_info
*tss
);
401 static const char follow_fork_mode_child
[] = "child";
402 static const char follow_fork_mode_parent
[] = "parent";
404 static const char *const follow_fork_mode_kind_names
[] = {
405 follow_fork_mode_child
,
406 follow_fork_mode_parent
,
410 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
412 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
413 struct cmd_list_element
*c
, const char *value
)
415 fprintf_filtered (file
,
416 _("Debugger response to a program "
417 "call of fork or vfork is \"%s\".\n"),
422 /* Handle changes to the inferior list based on the type of fork,
423 which process is being followed, and whether the other process
424 should be detached. On entry inferior_ptid must be the ptid of
425 the fork parent. At return inferior_ptid is the ptid of the
426 followed inferior. */
429 follow_fork_inferior (int follow_child
, int detach_fork
)
432 ptid_t parent_ptid
, child_ptid
;
434 has_vforked
= (inferior_thread ()->pending_follow
.kind
435 == TARGET_WAITKIND_VFORKED
);
436 parent_ptid
= inferior_ptid
;
437 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
440 && !non_stop
/* Non-stop always resumes both branches. */
441 && current_ui
->prompt_state
== PROMPT_BLOCKED
442 && !(follow_child
|| detach_fork
|| sched_multi
))
444 /* The parent stays blocked inside the vfork syscall until the
445 child execs or exits. If we don't let the child run, then
446 the parent stays blocked. If we're telling the parent to run
447 in the foreground, the user will not be able to ctrl-c to get
448 back the terminal, effectively hanging the debug session. */
449 fprintf_filtered (gdb_stderr
, _("\
450 Can not resume the parent process over vfork in the foreground while\n\
451 holding the child stopped. Try \"set detach-on-fork\" or \
452 \"set schedule-multiple\".\n"));
453 /* FIXME output string > 80 columns. */
459 /* Detach new forked process? */
462 /* Before detaching from the child, remove all breakpoints
463 from it. If we forked, then this has already been taken
464 care of by infrun.c. If we vforked however, any
465 breakpoint inserted in the parent is visible in the
466 child, even those added while stopped in a vfork
467 catchpoint. This will remove the breakpoints from the
468 parent also, but they'll be reinserted below. */
471 /* Keep breakpoints list in sync. */
472 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
475 if (info_verbose
|| debug_infrun
)
477 /* Ensure that we have a process ptid. */
478 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
480 target_terminal_ours_for_output ();
481 fprintf_filtered (gdb_stdlog
,
482 _("Detaching after %s from child %s.\n"),
483 has_vforked
? "vfork" : "fork",
484 target_pid_to_str (process_ptid
));
489 struct inferior
*parent_inf
, *child_inf
;
490 struct cleanup
*old_chain
;
492 /* Add process to GDB's tables. */
493 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
495 parent_inf
= current_inferior ();
496 child_inf
->attach_flag
= parent_inf
->attach_flag
;
497 copy_terminal_info (child_inf
, parent_inf
);
498 child_inf
->gdbarch
= parent_inf
->gdbarch
;
499 copy_inferior_target_desc_info (child_inf
, parent_inf
);
501 old_chain
= save_inferior_ptid ();
502 save_current_program_space ();
504 inferior_ptid
= child_ptid
;
505 add_thread (inferior_ptid
);
506 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
508 /* If this is a vfork child, then the address-space is
509 shared with the parent. */
512 child_inf
->pspace
= parent_inf
->pspace
;
513 child_inf
->aspace
= parent_inf
->aspace
;
515 /* The parent will be frozen until the child is done
516 with the shared region. Keep track of the
518 child_inf
->vfork_parent
= parent_inf
;
519 child_inf
->pending_detach
= 0;
520 parent_inf
->vfork_child
= child_inf
;
521 parent_inf
->pending_detach
= 0;
525 child_inf
->aspace
= new_address_space ();
526 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
527 child_inf
->removable
= 1;
528 set_current_program_space (child_inf
->pspace
);
529 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
531 /* Let the shared library layer (e.g., solib-svr4) learn
532 about this new process, relocate the cloned exec, pull
533 in shared libraries, and install the solib event
534 breakpoint. If a "cloned-VM" event was propagated
535 better throughout the core, this wouldn't be
537 solib_create_inferior_hook (0);
540 do_cleanups (old_chain
);
545 struct inferior
*parent_inf
;
547 parent_inf
= current_inferior ();
549 /* If we detached from the child, then we have to be careful
550 to not insert breakpoints in the parent until the child
551 is done with the shared memory region. However, if we're
552 staying attached to the child, then we can and should
553 insert breakpoints, so that we can debug it. A
554 subsequent child exec or exit is enough to know when does
555 the child stops using the parent's address space. */
556 parent_inf
->waiting_for_vfork_done
= detach_fork
;
557 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
562 /* Follow the child. */
563 struct inferior
*parent_inf
, *child_inf
;
564 struct program_space
*parent_pspace
;
566 if (info_verbose
|| debug_infrun
)
568 target_terminal_ours_for_output ();
569 fprintf_filtered (gdb_stdlog
,
570 _("Attaching after %s %s to child %s.\n"),
571 target_pid_to_str (parent_ptid
),
572 has_vforked
? "vfork" : "fork",
573 target_pid_to_str (child_ptid
));
576 /* Add the new inferior first, so that the target_detach below
577 doesn't unpush the target. */
579 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
581 parent_inf
= current_inferior ();
582 child_inf
->attach_flag
= parent_inf
->attach_flag
;
583 copy_terminal_info (child_inf
, parent_inf
);
584 child_inf
->gdbarch
= parent_inf
->gdbarch
;
585 copy_inferior_target_desc_info (child_inf
, parent_inf
);
587 parent_pspace
= parent_inf
->pspace
;
589 /* If we're vforking, we want to hold on to the parent until the
590 child exits or execs. At child exec or exit time we can
591 remove the old breakpoints from the parent and detach or
592 resume debugging it. Otherwise, detach the parent now; we'll
593 want to reuse it's program/address spaces, but we can't set
594 them to the child before removing breakpoints from the
595 parent, otherwise, the breakpoints module could decide to
596 remove breakpoints from the wrong process (since they'd be
597 assigned to the same address space). */
601 gdb_assert (child_inf
->vfork_parent
== NULL
);
602 gdb_assert (parent_inf
->vfork_child
== NULL
);
603 child_inf
->vfork_parent
= parent_inf
;
604 child_inf
->pending_detach
= 0;
605 parent_inf
->vfork_child
= child_inf
;
606 parent_inf
->pending_detach
= detach_fork
;
607 parent_inf
->waiting_for_vfork_done
= 0;
609 else if (detach_fork
)
611 if (info_verbose
|| debug_infrun
)
613 /* Ensure that we have a process ptid. */
614 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
616 target_terminal_ours_for_output ();
617 fprintf_filtered (gdb_stdlog
,
618 _("Detaching after fork from "
620 target_pid_to_str (process_ptid
));
623 target_detach (NULL
, 0);
626 /* Note that the detach above makes PARENT_INF dangling. */
628 /* Add the child thread to the appropriate lists, and switch to
629 this new thread, before cloning the program space, and
630 informing the solib layer about this new process. */
632 inferior_ptid
= child_ptid
;
633 add_thread (inferior_ptid
);
635 /* If this is a vfork child, then the address-space is shared
636 with the parent. If we detached from the parent, then we can
637 reuse the parent's program/address spaces. */
638 if (has_vforked
|| detach_fork
)
640 child_inf
->pspace
= parent_pspace
;
641 child_inf
->aspace
= child_inf
->pspace
->aspace
;
645 child_inf
->aspace
= new_address_space ();
646 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
647 child_inf
->removable
= 1;
648 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
649 set_current_program_space (child_inf
->pspace
);
650 clone_program_space (child_inf
->pspace
, parent_pspace
);
652 /* Let the shared library layer (e.g., solib-svr4) learn
653 about this new process, relocate the cloned exec, pull in
654 shared libraries, and install the solib event breakpoint.
655 If a "cloned-VM" event was propagated better throughout
656 the core, this wouldn't be required. */
657 solib_create_inferior_hook (0);
661 return target_follow_fork (follow_child
, detach_fork
);
664 /* Tell the target to follow the fork we're stopped at. Returns true
665 if the inferior should be resumed; false, if the target for some
666 reason decided it's best not to resume. */
671 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
672 int should_resume
= 1;
673 struct thread_info
*tp
;
675 /* Copy user stepping state to the new inferior thread. FIXME: the
676 followed fork child thread should have a copy of most of the
677 parent thread structure's run control related fields, not just these.
678 Initialized to avoid "may be used uninitialized" warnings from gcc. */
679 struct breakpoint
*step_resume_breakpoint
= NULL
;
680 struct breakpoint
*exception_resume_breakpoint
= NULL
;
681 CORE_ADDR step_range_start
= 0;
682 CORE_ADDR step_range_end
= 0;
683 struct frame_id step_frame_id
= { 0 };
684 struct thread_fsm
*thread_fsm
= NULL
;
689 struct target_waitstatus wait_status
;
691 /* Get the last target status returned by target_wait(). */
692 get_last_target_status (&wait_ptid
, &wait_status
);
694 /* If not stopped at a fork event, then there's nothing else to
696 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
697 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
700 /* Check if we switched over from WAIT_PTID, since the event was
702 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
703 && !ptid_equal (inferior_ptid
, wait_ptid
))
705 /* We did. Switch back to WAIT_PTID thread, to tell the
706 target to follow it (in either direction). We'll
707 afterwards refuse to resume, and inform the user what
709 switch_to_thread (wait_ptid
);
714 tp
= inferior_thread ();
716 /* If there were any forks/vforks that were caught and are now to be
717 followed, then do so now. */
718 switch (tp
->pending_follow
.kind
)
720 case TARGET_WAITKIND_FORKED
:
721 case TARGET_WAITKIND_VFORKED
:
723 ptid_t parent
, child
;
725 /* If the user did a next/step, etc, over a fork call,
726 preserve the stepping state in the fork child. */
727 if (follow_child
&& should_resume
)
729 step_resume_breakpoint
= clone_momentary_breakpoint
730 (tp
->control
.step_resume_breakpoint
);
731 step_range_start
= tp
->control
.step_range_start
;
732 step_range_end
= tp
->control
.step_range_end
;
733 step_frame_id
= tp
->control
.step_frame_id
;
734 exception_resume_breakpoint
735 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
736 thread_fsm
= tp
->thread_fsm
;
738 /* For now, delete the parent's sr breakpoint, otherwise,
739 parent/child sr breakpoints are considered duplicates,
740 and the child version will not be installed. Remove
741 this when the breakpoints module becomes aware of
742 inferiors and address spaces. */
743 delete_step_resume_breakpoint (tp
);
744 tp
->control
.step_range_start
= 0;
745 tp
->control
.step_range_end
= 0;
746 tp
->control
.step_frame_id
= null_frame_id
;
747 delete_exception_resume_breakpoint (tp
);
748 tp
->thread_fsm
= NULL
;
751 parent
= inferior_ptid
;
752 child
= tp
->pending_follow
.value
.related_pid
;
754 /* Set up inferior(s) as specified by the caller, and tell the
755 target to do whatever is necessary to follow either parent
757 if (follow_fork_inferior (follow_child
, detach_fork
))
759 /* Target refused to follow, or there's some other reason
760 we shouldn't resume. */
765 /* This pending follow fork event is now handled, one way
766 or another. The previous selected thread may be gone
767 from the lists by now, but if it is still around, need
768 to clear the pending follow request. */
769 tp
= find_thread_ptid (parent
);
771 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
773 /* This makes sure we don't try to apply the "Switched
774 over from WAIT_PID" logic above. */
775 nullify_last_target_wait_ptid ();
777 /* If we followed the child, switch to it... */
780 switch_to_thread (child
);
782 /* ... and preserve the stepping state, in case the
783 user was stepping over the fork call. */
786 tp
= inferior_thread ();
787 tp
->control
.step_resume_breakpoint
788 = step_resume_breakpoint
;
789 tp
->control
.step_range_start
= step_range_start
;
790 tp
->control
.step_range_end
= step_range_end
;
791 tp
->control
.step_frame_id
= step_frame_id
;
792 tp
->control
.exception_resume_breakpoint
793 = exception_resume_breakpoint
;
794 tp
->thread_fsm
= thread_fsm
;
798 /* If we get here, it was because we're trying to
799 resume from a fork catchpoint, but, the user
800 has switched threads away from the thread that
801 forked. In that case, the resume command
802 issued is most likely not applicable to the
803 child, so just warn, and refuse to resume. */
804 warning (_("Not resuming: switched threads "
805 "before following fork child."));
808 /* Reset breakpoints in the child as appropriate. */
809 follow_inferior_reset_breakpoints ();
812 switch_to_thread (parent
);
816 case TARGET_WAITKIND_SPURIOUS
:
817 /* Nothing to follow. */
820 internal_error (__FILE__
, __LINE__
,
821 "Unexpected pending_follow.kind %d\n",
822 tp
->pending_follow
.kind
);
826 return should_resume
;
830 follow_inferior_reset_breakpoints (void)
832 struct thread_info
*tp
= inferior_thread ();
834 /* Was there a step_resume breakpoint? (There was if the user
835 did a "next" at the fork() call.) If so, explicitly reset its
836 thread number. Cloned step_resume breakpoints are disabled on
837 creation, so enable it here now that it is associated with the
840 step_resumes are a form of bp that are made to be per-thread.
841 Since we created the step_resume bp when the parent process
842 was being debugged, and now are switching to the child process,
843 from the breakpoint package's viewpoint, that's a switch of
844 "threads". We must update the bp's notion of which thread
845 it is for, or it'll be ignored when it triggers. */
847 if (tp
->control
.step_resume_breakpoint
)
849 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
850 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
853 /* Treat exception_resume breakpoints like step_resume breakpoints. */
854 if (tp
->control
.exception_resume_breakpoint
)
856 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
857 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
860 /* Reinsert all breakpoints in the child. The user may have set
861 breakpoints after catching the fork, in which case those
862 were never set in the child, but only in the parent. This makes
863 sure the inserted breakpoints match the breakpoint list. */
865 breakpoint_re_set ();
866 insert_breakpoints ();
869 /* The child has exited or execed: resume threads of the parent the
870 user wanted to be executing. */
873 proceed_after_vfork_done (struct thread_info
*thread
,
876 int pid
= * (int *) arg
;
878 if (ptid_get_pid (thread
->ptid
) == pid
879 && is_running (thread
->ptid
)
880 && !is_executing (thread
->ptid
)
881 && !thread
->stop_requested
882 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
885 fprintf_unfiltered (gdb_stdlog
,
886 "infrun: resuming vfork parent thread %s\n",
887 target_pid_to_str (thread
->ptid
));
889 switch_to_thread (thread
->ptid
);
890 clear_proceed_status (0);
891 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
897 /* Called whenever we notice an exec or exit event, to handle
898 detaching or resuming a vfork parent. */
901 handle_vfork_child_exec_or_exit (int exec
)
903 struct inferior
*inf
= current_inferior ();
905 if (inf
->vfork_parent
)
907 int resume_parent
= -1;
909 /* This exec or exit marks the end of the shared memory region
910 between the parent and the child. If the user wanted to
911 detach from the parent, now is the time. */
913 if (inf
->vfork_parent
->pending_detach
)
915 struct thread_info
*tp
;
916 struct cleanup
*old_chain
;
917 struct program_space
*pspace
;
918 struct address_space
*aspace
;
920 /* follow-fork child, detach-on-fork on. */
922 inf
->vfork_parent
->pending_detach
= 0;
926 /* If we're handling a child exit, then inferior_ptid
927 points at the inferior's pid, not to a thread. */
928 old_chain
= save_inferior_ptid ();
929 save_current_program_space ();
930 save_current_inferior ();
933 old_chain
= save_current_space_and_thread ();
935 /* We're letting loose of the parent. */
936 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
937 switch_to_thread (tp
->ptid
);
939 /* We're about to detach from the parent, which implicitly
940 removes breakpoints from its address space. There's a
941 catch here: we want to reuse the spaces for the child,
942 but, parent/child are still sharing the pspace at this
943 point, although the exec in reality makes the kernel give
944 the child a fresh set of new pages. The problem here is
945 that the breakpoints module being unaware of this, would
946 likely chose the child process to write to the parent
947 address space. Swapping the child temporarily away from
948 the spaces has the desired effect. Yes, this is "sort
951 pspace
= inf
->pspace
;
952 aspace
= inf
->aspace
;
956 if (debug_infrun
|| info_verbose
)
958 target_terminal_ours_for_output ();
962 fprintf_filtered (gdb_stdlog
,
963 _("Detaching vfork parent process "
964 "%d after child exec.\n"),
965 inf
->vfork_parent
->pid
);
969 fprintf_filtered (gdb_stdlog
,
970 _("Detaching vfork parent process "
971 "%d after child exit.\n"),
972 inf
->vfork_parent
->pid
);
976 target_detach (NULL
, 0);
979 inf
->pspace
= pspace
;
980 inf
->aspace
= aspace
;
982 do_cleanups (old_chain
);
986 /* We're staying attached to the parent, so, really give the
987 child a new address space. */
988 inf
->pspace
= add_program_space (maybe_new_address_space ());
989 inf
->aspace
= inf
->pspace
->aspace
;
991 set_current_program_space (inf
->pspace
);
993 resume_parent
= inf
->vfork_parent
->pid
;
995 /* Break the bonds. */
996 inf
->vfork_parent
->vfork_child
= NULL
;
1000 struct cleanup
*old_chain
;
1001 struct program_space
*pspace
;
1003 /* If this is a vfork child exiting, then the pspace and
1004 aspaces were shared with the parent. Since we're
1005 reporting the process exit, we'll be mourning all that is
1006 found in the address space, and switching to null_ptid,
1007 preparing to start a new inferior. But, since we don't
1008 want to clobber the parent's address/program spaces, we
1009 go ahead and create a new one for this exiting
1012 /* Switch to null_ptid, so that clone_program_space doesn't want
1013 to read the selected frame of a dead process. */
1014 old_chain
= save_inferior_ptid ();
1015 inferior_ptid
= null_ptid
;
1017 /* This inferior is dead, so avoid giving the breakpoints
1018 module the option to write through to it (cloning a
1019 program space resets breakpoints). */
1022 pspace
= add_program_space (maybe_new_address_space ());
1023 set_current_program_space (pspace
);
1025 inf
->symfile_flags
= SYMFILE_NO_READ
;
1026 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1027 inf
->pspace
= pspace
;
1028 inf
->aspace
= pspace
->aspace
;
1030 /* Put back inferior_ptid. We'll continue mourning this
1032 do_cleanups (old_chain
);
1034 resume_parent
= inf
->vfork_parent
->pid
;
1035 /* Break the bonds. */
1036 inf
->vfork_parent
->vfork_child
= NULL
;
1039 inf
->vfork_parent
= NULL
;
1041 gdb_assert (current_program_space
== inf
->pspace
);
1043 if (non_stop
&& resume_parent
!= -1)
1045 /* If the user wanted the parent to be running, let it go
1047 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1050 fprintf_unfiltered (gdb_stdlog
,
1051 "infrun: resuming vfork parent process %d\n",
1054 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1056 do_cleanups (old_chain
);
1061 /* Enum strings for "set|show follow-exec-mode". */
1063 static const char follow_exec_mode_new
[] = "new";
1064 static const char follow_exec_mode_same
[] = "same";
1065 static const char *const follow_exec_mode_names
[] =
1067 follow_exec_mode_new
,
1068 follow_exec_mode_same
,
1072 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1074 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1075 struct cmd_list_element
*c
, const char *value
)
1077 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1080 /* EXECD_PATHNAME is assumed to be non-NULL. */
1083 follow_exec (ptid_t ptid
, char *execd_pathname
)
1085 struct thread_info
*th
, *tmp
;
1086 struct inferior
*inf
= current_inferior ();
1087 int pid
= ptid_get_pid (ptid
);
1088 ptid_t process_ptid
;
1090 /* This is an exec event that we actually wish to pay attention to.
1091 Refresh our symbol table to the newly exec'd program, remove any
1092 momentary bp's, etc.
1094 If there are breakpoints, they aren't really inserted now,
1095 since the exec() transformed our inferior into a fresh set
1098 We want to preserve symbolic breakpoints on the list, since
1099 we have hopes that they can be reset after the new a.out's
1100 symbol table is read.
1102 However, any "raw" breakpoints must be removed from the list
1103 (e.g., the solib bp's), since their address is probably invalid
1106 And, we DON'T want to call delete_breakpoints() here, since
1107 that may write the bp's "shadow contents" (the instruction
1108 value that was overwritten witha TRAP instruction). Since
1109 we now have a new a.out, those shadow contents aren't valid. */
1111 mark_breakpoints_out ();
1113 /* The target reports the exec event to the main thread, even if
1114 some other thread does the exec, and even if the main thread was
1115 stopped or already gone. We may still have non-leader threads of
1116 the process on our list. E.g., on targets that don't have thread
1117 exit events (like remote); or on native Linux in non-stop mode if
1118 there were only two threads in the inferior and the non-leader
1119 one is the one that execs (and nothing forces an update of the
1120 thread list up to here). When debugging remotely, it's best to
1121 avoid extra traffic, when possible, so avoid syncing the thread
1122 list with the target, and instead go ahead and delete all threads
1123 of the process but one that reported the event. Note this must
1124 be done before calling update_breakpoints_after_exec, as
1125 otherwise clearing the threads' resources would reference stale
1126 thread breakpoints -- it may have been one of these threads that
1127 stepped across the exec. We could just clear their stepping
1128 states, but as long as we're iterating, might as well delete
1129 them. Deleting them now rather than at the next user-visible
1130 stop provides a nicer sequence of events for user and MI
1132 ALL_THREADS_SAFE (th
, tmp
)
1133 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1134 delete_thread (th
->ptid
);
1136 /* We also need to clear any left over stale state for the
1137 leader/event thread. E.g., if there was any step-resume
1138 breakpoint or similar, it's gone now. We cannot truly
1139 step-to-next statement through an exec(). */
1140 th
= inferior_thread ();
1141 th
->control
.step_resume_breakpoint
= NULL
;
1142 th
->control
.exception_resume_breakpoint
= NULL
;
1143 th
->control
.single_step_breakpoints
= NULL
;
1144 th
->control
.step_range_start
= 0;
1145 th
->control
.step_range_end
= 0;
1147 /* The user may have had the main thread held stopped in the
1148 previous image (e.g., schedlock on, or non-stop). Release
1150 th
->stop_requested
= 0;
1152 update_breakpoints_after_exec ();
1154 /* What is this a.out's name? */
1155 process_ptid
= pid_to_ptid (pid
);
1156 printf_unfiltered (_("%s is executing new program: %s\n"),
1157 target_pid_to_str (process_ptid
),
1160 /* We've followed the inferior through an exec. Therefore, the
1161 inferior has essentially been killed & reborn. */
1163 gdb_flush (gdb_stdout
);
1165 breakpoint_init_inferior (inf_execd
);
1167 if (*gdb_sysroot
!= '\0')
1169 char *name
= exec_file_find (execd_pathname
, NULL
);
1171 execd_pathname
= (char *) alloca (strlen (name
) + 1);
1172 strcpy (execd_pathname
, name
);
1176 /* Reset the shared library package. This ensures that we get a
1177 shlib event when the child reaches "_start", at which point the
1178 dld will have had a chance to initialize the child. */
1179 /* Also, loading a symbol file below may trigger symbol lookups, and
1180 we don't want those to be satisfied by the libraries of the
1181 previous incarnation of this process. */
1182 no_shared_libraries (NULL
, 0);
1184 if (follow_exec_mode_string
== follow_exec_mode_new
)
1186 /* The user wants to keep the old inferior and program spaces
1187 around. Create a new fresh one, and switch to it. */
1189 /* Do exit processing for the original inferior before adding
1190 the new inferior so we don't have two active inferiors with
1191 the same ptid, which can confuse find_inferior_ptid. */
1192 exit_inferior_num_silent (current_inferior ()->num
);
1194 inf
= add_inferior_with_spaces ();
1196 target_follow_exec (inf
, execd_pathname
);
1198 set_current_inferior (inf
);
1199 set_current_program_space (inf
->pspace
);
1204 /* The old description may no longer be fit for the new image.
1205 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1206 old description; we'll read a new one below. No need to do
1207 this on "follow-exec-mode new", as the old inferior stays
1208 around (its description is later cleared/refetched on
1210 target_clear_description ();
1213 gdb_assert (current_program_space
== inf
->pspace
);
1215 /* That a.out is now the one to use. */
1216 exec_file_attach (execd_pathname
, 0);
1218 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1219 (Position Independent Executable) main symbol file will get applied by
1220 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1221 the breakpoints with the zero displacement. */
1223 symbol_file_add (execd_pathname
,
1225 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
1228 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
1229 set_initial_language ();
1231 /* If the target can specify a description, read it. Must do this
1232 after flipping to the new executable (because the target supplied
1233 description must be compatible with the executable's
1234 architecture, and the old executable may e.g., be 32-bit, while
1235 the new one 64-bit), and before anything involving memory or
1237 target_find_description ();
1239 solib_create_inferior_hook (0);
1241 jit_inferior_created_hook ();
1243 breakpoint_re_set ();
1245 /* Reinsert all breakpoints. (Those which were symbolic have
1246 been reset to the proper address in the new a.out, thanks
1247 to symbol_file_command...). */
1248 insert_breakpoints ();
1250 /* The next resume of this inferior should bring it to the shlib
1251 startup breakpoints. (If the user had also set bp's on
1252 "main" from the old (parent) process, then they'll auto-
1253 matically get reset there in the new process.). */
1256 /* The queue of threads that need to do a step-over operation to get
1257 past e.g., a breakpoint. What technique is used to step over the
1258 breakpoint/watchpoint does not matter -- all threads end up in the
1259 same queue, to maintain rough temporal order of execution, in order
1260 to avoid starvation, otherwise, we could e.g., find ourselves
1261 constantly stepping the same couple threads past their breakpoints
1262 over and over, if the single-step finish fast enough. */
1263 struct thread_info
*step_over_queue_head
;
1265 /* Bit flags indicating what the thread needs to step over. */
1267 enum step_over_what_flag
1269 /* Step over a breakpoint. */
1270 STEP_OVER_BREAKPOINT
= 1,
1272 /* Step past a non-continuable watchpoint, in order to let the
1273 instruction execute so we can evaluate the watchpoint
1275 STEP_OVER_WATCHPOINT
= 2
1277 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1279 /* Info about an instruction that is being stepped over. */
1281 struct step_over_info
1283 /* If we're stepping past a breakpoint, this is the address space
1284 and address of the instruction the breakpoint is set at. We'll
1285 skip inserting all breakpoints here. Valid iff ASPACE is
1287 struct address_space
*aspace
;
1290 /* The instruction being stepped over triggers a nonsteppable
1291 watchpoint. If true, we'll skip inserting watchpoints. */
1292 int nonsteppable_watchpoint_p
;
1294 /* The thread's global number. */
1298 /* The step-over info of the location that is being stepped over.
1300 Note that with async/breakpoint always-inserted mode, a user might
1301 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1302 being stepped over. As setting a new breakpoint inserts all
1303 breakpoints, we need to make sure the breakpoint being stepped over
1304 isn't inserted then. We do that by only clearing the step-over
1305 info when the step-over is actually finished (or aborted).
1307 Presently GDB can only step over one breakpoint at any given time.
1308 Given threads that can't run code in the same address space as the
1309 breakpoint's can't really miss the breakpoint, GDB could be taught
1310 to step-over at most one breakpoint per address space (so this info
1311 could move to the address space object if/when GDB is extended).
1312 The set of breakpoints being stepped over will normally be much
1313 smaller than the set of all breakpoints, so a flag in the
1314 breakpoint location structure would be wasteful. A separate list
1315 also saves complexity and run-time, as otherwise we'd have to go
1316 through all breakpoint locations clearing their flag whenever we
1317 start a new sequence. Similar considerations weigh against storing
1318 this info in the thread object. Plus, not all step overs actually
1319 have breakpoint locations -- e.g., stepping past a single-step
1320 breakpoint, or stepping to complete a non-continuable
1322 static struct step_over_info step_over_info
;
1324 /* Record the address of the breakpoint/instruction we're currently
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 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
2270 user_visible_resume_ptid (int step
)
2276 /* With non-stop mode on, threads are always handled
2278 resume_ptid
= inferior_ptid
;
2280 else if ((scheduler_mode
== schedlock_on
)
2281 || (scheduler_mode
== schedlock_step
&& step
))
2283 /* User-settable 'scheduler' mode requires solo thread
2285 resume_ptid
= inferior_ptid
;
2287 else if ((scheduler_mode
== schedlock_replay
)
2288 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2290 /* User-settable 'scheduler' mode requires solo thread resume in replay
2292 resume_ptid
= inferior_ptid
;
2294 else if (!sched_multi
&& target_supports_multi_process ())
2296 /* Resume all threads of the current process (and none of other
2298 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2302 /* Resume all threads of all processes. */
2303 resume_ptid
= RESUME_ALL
;
2309 /* Return a ptid representing the set of threads that we will resume,
2310 in the perspective of the target, assuming run control handling
2311 does not require leaving some threads stopped (e.g., stepping past
2312 breakpoint). USER_STEP indicates whether we're about to start the
2313 target for a stepping command. */
2316 internal_resume_ptid (int user_step
)
2318 /* In non-stop, we always control threads individually. Note that
2319 the target may always work in non-stop mode even with "set
2320 non-stop off", in which case user_visible_resume_ptid could
2321 return a wildcard ptid. */
2322 if (target_is_non_stop_p ())
2323 return inferior_ptid
;
2325 return user_visible_resume_ptid (user_step
);
2328 /* Wrapper for target_resume, that handles infrun-specific
2332 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2334 struct thread_info
*tp
= inferior_thread ();
2336 /* Install inferior's terminal modes. */
2337 target_terminal_inferior ();
2339 /* Avoid confusing the next resume, if the next stop/resume
2340 happens to apply to another thread. */
2341 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2343 /* Advise target which signals may be handled silently.
2345 If we have removed breakpoints because we are stepping over one
2346 in-line (in any thread), we need to receive all signals to avoid
2347 accidentally skipping a breakpoint during execution of a signal
2350 Likewise if we're displaced stepping, otherwise a trap for a
2351 breakpoint in a signal handler might be confused with the
2352 displaced step finishing. We don't make the displaced_step_fixup
2353 step distinguish the cases instead, because:
2355 - a backtrace while stopped in the signal handler would show the
2356 scratch pad as frame older than the signal handler, instead of
2357 the real mainline code.
2359 - when the thread is later resumed, the signal handler would
2360 return to the scratch pad area, which would no longer be
2362 if (step_over_info_valid_p ()
2363 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2364 target_pass_signals (0, NULL
);
2366 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2368 target_resume (resume_ptid
, step
, sig
);
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
;
2989 /* If we're stopped at a fork/vfork, follow the branch set by the
2990 "set follow-fork-mode" command; otherwise, we'll just proceed
2991 resuming the current thread. */
2992 if (!follow_fork ())
2994 /* The target for some reason decided not to resume. */
2996 if (target_can_async_p ())
2997 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3001 /* We'll update this if & when we switch to a new thread. */
3002 previous_inferior_ptid
= inferior_ptid
;
3004 regcache
= get_current_regcache ();
3005 gdbarch
= get_regcache_arch (regcache
);
3006 aspace
= get_regcache_aspace (regcache
);
3007 pc
= regcache_read_pc (regcache
);
3008 tp
= inferior_thread ();
3010 /* Fill in with reasonable starting values. */
3011 init_thread_stepping_state (tp
);
3013 gdb_assert (!thread_is_in_step_over_chain (tp
));
3015 if (addr
== (CORE_ADDR
) -1)
3018 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3019 && execution_direction
!= EXEC_REVERSE
)
3020 /* There is a breakpoint at the address we will resume at,
3021 step one instruction before inserting breakpoints so that
3022 we do not stop right away (and report a second hit at this
3025 Note, we don't do this in reverse, because we won't
3026 actually be executing the breakpoint insn anyway.
3027 We'll be (un-)executing the previous instruction. */
3028 tp
->stepping_over_breakpoint
= 1;
3029 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3030 && gdbarch_single_step_through_delay (gdbarch
,
3031 get_current_frame ()))
3032 /* We stepped onto an instruction that needs to be stepped
3033 again before re-inserting the breakpoint, do so. */
3034 tp
->stepping_over_breakpoint
= 1;
3038 regcache_write_pc (regcache
, addr
);
3041 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3042 tp
->suspend
.stop_signal
= siggnal
;
3044 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3046 /* If an exception is thrown from this point on, make sure to
3047 propagate GDB's knowledge of the executing state to the
3048 frontend/user running state. */
3049 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3051 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3052 threads (e.g., we might need to set threads stepping over
3053 breakpoints first), from the user/frontend's point of view, all
3054 threads in RESUME_PTID are now running. Unless we're calling an
3055 inferior function, as in that case we pretend the inferior
3056 doesn't run at all. */
3057 if (!tp
->control
.in_infcall
)
3058 set_running (resume_ptid
, 1);
3061 fprintf_unfiltered (gdb_stdlog
,
3062 "infrun: proceed (addr=%s, signal=%s)\n",
3063 paddress (gdbarch
, addr
),
3064 gdb_signal_to_symbol_string (siggnal
));
3066 annotate_starting ();
3068 /* Make sure that output from GDB appears before output from the
3070 gdb_flush (gdb_stdout
);
3072 /* In a multi-threaded task we may select another thread and
3073 then continue or step.
3075 But if a thread that we're resuming had stopped at a breakpoint,
3076 it will immediately cause another breakpoint stop without any
3077 execution (i.e. it will report a breakpoint hit incorrectly). So
3078 we must step over it first.
3080 Look for threads other than the current (TP) that reported a
3081 breakpoint hit and haven't been resumed yet since. */
3083 /* If scheduler locking applies, we can avoid iterating over all
3085 if (!non_stop
&& !schedlock_applies (tp
))
3087 struct thread_info
*current
= tp
;
3089 ALL_NON_EXITED_THREADS (tp
)
3091 /* Ignore the current thread here. It's handled
3096 /* Ignore threads of processes we're not resuming. */
3097 if (!ptid_match (tp
->ptid
, resume_ptid
))
3100 if (!thread_still_needs_step_over (tp
))
3103 gdb_assert (!thread_is_in_step_over_chain (tp
));
3106 fprintf_unfiltered (gdb_stdlog
,
3107 "infrun: need to step-over [%s] first\n",
3108 target_pid_to_str (tp
->ptid
));
3110 thread_step_over_chain_enqueue (tp
);
3116 /* Enqueue the current thread last, so that we move all other
3117 threads over their breakpoints first. */
3118 if (tp
->stepping_over_breakpoint
)
3119 thread_step_over_chain_enqueue (tp
);
3121 /* If the thread isn't started, we'll still need to set its prev_pc,
3122 so that switch_back_to_stepped_thread knows the thread hasn't
3123 advanced. Must do this before resuming any thread, as in
3124 all-stop/remote, once we resume we can't send any other packet
3125 until the target stops again. */
3126 tp
->prev_pc
= regcache_read_pc (regcache
);
3128 started
= start_step_over ();
3130 if (step_over_info_valid_p ())
3132 /* Either this thread started a new in-line step over, or some
3133 other thread was already doing one. In either case, don't
3134 resume anything else until the step-over is finished. */
3136 else if (started
&& !target_is_non_stop_p ())
3138 /* A new displaced stepping sequence was started. In all-stop,
3139 we can't talk to the target anymore until it next stops. */
3141 else if (!non_stop
&& target_is_non_stop_p ())
3143 /* In all-stop, but the target is always in non-stop mode.
3144 Start all other threads that are implicitly resumed too. */
3145 ALL_NON_EXITED_THREADS (tp
)
3147 /* Ignore threads of processes we're not resuming. */
3148 if (!ptid_match (tp
->ptid
, resume_ptid
))
3154 fprintf_unfiltered (gdb_stdlog
,
3155 "infrun: proceed: [%s] resumed\n",
3156 target_pid_to_str (tp
->ptid
));
3157 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3161 if (thread_is_in_step_over_chain (tp
))
3164 fprintf_unfiltered (gdb_stdlog
,
3165 "infrun: proceed: [%s] needs step-over\n",
3166 target_pid_to_str (tp
->ptid
));
3171 fprintf_unfiltered (gdb_stdlog
,
3172 "infrun: proceed: resuming %s\n",
3173 target_pid_to_str (tp
->ptid
));
3175 reset_ecs (ecs
, tp
);
3176 switch_to_thread (tp
->ptid
);
3177 keep_going_pass_signal (ecs
);
3178 if (!ecs
->wait_some_more
)
3179 error (_("Command aborted."));
3182 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3184 /* The thread wasn't started, and isn't queued, run it now. */
3185 reset_ecs (ecs
, tp
);
3186 switch_to_thread (tp
->ptid
);
3187 keep_going_pass_signal (ecs
);
3188 if (!ecs
->wait_some_more
)
3189 error (_("Command aborted."));
3192 discard_cleanups (old_chain
);
3194 /* Tell the event loop to wait for it to stop. If the target
3195 supports asynchronous execution, it'll do this from within
3197 if (!target_can_async_p ())
3198 mark_async_event_handler (infrun_async_inferior_event_token
);
3202 /* Start remote-debugging of a machine over a serial link. */
3205 start_remote (int from_tty
)
3207 struct inferior
*inferior
;
3209 inferior
= current_inferior ();
3210 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3212 /* Always go on waiting for the target, regardless of the mode. */
3213 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3214 indicate to wait_for_inferior that a target should timeout if
3215 nothing is returned (instead of just blocking). Because of this,
3216 targets expecting an immediate response need to, internally, set
3217 things up so that the target_wait() is forced to eventually
3219 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3220 differentiate to its caller what the state of the target is after
3221 the initial open has been performed. Here we're assuming that
3222 the target has stopped. It should be possible to eventually have
3223 target_open() return to the caller an indication that the target
3224 is currently running and GDB state should be set to the same as
3225 for an async run. */
3226 wait_for_inferior ();
3228 /* Now that the inferior has stopped, do any bookkeeping like
3229 loading shared libraries. We want to do this before normal_stop,
3230 so that the displayed frame is up to date. */
3231 post_create_inferior (¤t_target
, from_tty
);
3236 /* Initialize static vars when a new inferior begins. */
3239 init_wait_for_inferior (void)
3241 /* These are meaningless until the first time through wait_for_inferior. */
3243 breakpoint_init_inferior (inf_starting
);
3245 clear_proceed_status (0);
3247 target_last_wait_ptid
= minus_one_ptid
;
3249 previous_inferior_ptid
= inferior_ptid
;
3251 /* Discard any skipped inlined frames. */
3252 clear_inline_frame_state (minus_one_ptid
);
3257 static void handle_inferior_event (struct execution_control_state
*ecs
);
3259 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3260 struct execution_control_state
*ecs
);
3261 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3262 struct execution_control_state
*ecs
);
3263 static void handle_signal_stop (struct execution_control_state
*ecs
);
3264 static void check_exception_resume (struct execution_control_state
*,
3265 struct frame_info
*);
3267 static void end_stepping_range (struct execution_control_state
*ecs
);
3268 static void stop_waiting (struct execution_control_state
*ecs
);
3269 static void keep_going (struct execution_control_state
*ecs
);
3270 static void process_event_stop_test (struct execution_control_state
*ecs
);
3271 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3273 /* Callback for iterate over threads. If the thread is stopped, but
3274 the user/frontend doesn't know about that yet, go through
3275 normal_stop, as if the thread had just stopped now. ARG points at
3276 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
3277 ptid_is_pid(PTID) is true, applies to all threads of the process
3278 pointed at by PTID. Otherwise, apply only to the thread pointed by
3282 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
3284 ptid_t ptid
= * (ptid_t
*) arg
;
3286 if ((ptid_equal (info
->ptid
, ptid
)
3287 || ptid_equal (minus_one_ptid
, ptid
)
3288 || (ptid_is_pid (ptid
)
3289 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
3290 && is_running (info
->ptid
)
3291 && !is_executing (info
->ptid
))
3293 struct cleanup
*old_chain
;
3294 struct execution_control_state ecss
;
3295 struct execution_control_state
*ecs
= &ecss
;
3297 memset (ecs
, 0, sizeof (*ecs
));
3299 old_chain
= make_cleanup_restore_current_thread ();
3301 overlay_cache_invalid
= 1;
3302 /* Flush target cache before starting to handle each event.
3303 Target was running and cache could be stale. This is just a
3304 heuristic. Running threads may modify target memory, but we
3305 don't get any event. */
3306 target_dcache_invalidate ();
3308 /* Go through handle_inferior_event/normal_stop, so we always
3309 have consistent output as if the stop event had been
3311 ecs
->ptid
= info
->ptid
;
3312 ecs
->event_thread
= info
;
3313 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
3314 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
3316 handle_inferior_event (ecs
);
3318 if (!ecs
->wait_some_more
)
3320 /* Cancel any running execution command. */
3321 thread_cancel_execution_command (info
);
3326 do_cleanups (old_chain
);
3332 /* This function is attached as a "thread_stop_requested" observer.
3333 Cleanup local state that assumed the PTID was to be resumed, and
3334 report the stop to the frontend. */
3337 infrun_thread_stop_requested (ptid_t ptid
)
3339 struct thread_info
*tp
;
3341 /* PTID was requested to stop. Remove matching threads from the
3342 step-over queue, so we don't try to resume them
3344 ALL_NON_EXITED_THREADS (tp
)
3345 if (ptid_match (tp
->ptid
, ptid
))
3347 if (thread_is_in_step_over_chain (tp
))
3348 thread_step_over_chain_remove (tp
);
3351 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
3355 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3357 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3358 nullify_last_target_wait_ptid ();
3361 /* Delete the step resume, single-step and longjmp/exception resume
3362 breakpoints of TP. */
3365 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3367 delete_step_resume_breakpoint (tp
);
3368 delete_exception_resume_breakpoint (tp
);
3369 delete_single_step_breakpoints (tp
);
3372 /* If the target still has execution, call FUNC for each thread that
3373 just stopped. In all-stop, that's all the non-exited threads; in
3374 non-stop, that's the current thread, only. */
3376 typedef void (*for_each_just_stopped_thread_callback_func
)
3377 (struct thread_info
*tp
);
3380 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3382 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3385 if (target_is_non_stop_p ())
3387 /* If in non-stop mode, only the current thread stopped. */
3388 func (inferior_thread ());
3392 struct thread_info
*tp
;
3394 /* In all-stop mode, all threads have stopped. */
3395 ALL_NON_EXITED_THREADS (tp
)
3402 /* Delete the step resume and longjmp/exception resume breakpoints of
3403 the threads that just stopped. */
3406 delete_just_stopped_threads_infrun_breakpoints (void)
3408 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3411 /* Delete the single-step breakpoints of the threads that just
3415 delete_just_stopped_threads_single_step_breakpoints (void)
3417 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3420 /* A cleanup wrapper. */
3423 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3425 delete_just_stopped_threads_infrun_breakpoints ();
3431 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3432 const struct target_waitstatus
*ws
)
3434 char *status_string
= target_waitstatus_to_string (ws
);
3435 struct ui_file
*tmp_stream
= mem_fileopen ();
3438 /* The text is split over several lines because it was getting too long.
3439 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3440 output as a unit; we want only one timestamp printed if debug_timestamp
3443 fprintf_unfiltered (tmp_stream
,
3444 "infrun: target_wait (%d.%ld.%ld",
3445 ptid_get_pid (waiton_ptid
),
3446 ptid_get_lwp (waiton_ptid
),
3447 ptid_get_tid (waiton_ptid
));
3448 if (ptid_get_pid (waiton_ptid
) != -1)
3449 fprintf_unfiltered (tmp_stream
,
3450 " [%s]", target_pid_to_str (waiton_ptid
));
3451 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3452 fprintf_unfiltered (tmp_stream
,
3453 "infrun: %d.%ld.%ld [%s],\n",
3454 ptid_get_pid (result_ptid
),
3455 ptid_get_lwp (result_ptid
),
3456 ptid_get_tid (result_ptid
),
3457 target_pid_to_str (result_ptid
));
3458 fprintf_unfiltered (tmp_stream
,
3462 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3464 /* This uses %s in part to handle %'s in the text, but also to avoid
3465 a gcc error: the format attribute requires a string literal. */
3466 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3468 xfree (status_string
);
3470 ui_file_delete (tmp_stream
);
3473 /* Select a thread at random, out of those which are resumed and have
3476 static struct thread_info
*
3477 random_pending_event_thread (ptid_t waiton_ptid
)
3479 struct thread_info
*event_tp
;
3481 int random_selector
;
3483 /* First see how many events we have. Count only resumed threads
3484 that have an event pending. */
3485 ALL_NON_EXITED_THREADS (event_tp
)
3486 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3487 && event_tp
->resumed
3488 && event_tp
->suspend
.waitstatus_pending_p
)
3491 if (num_events
== 0)
3494 /* Now randomly pick a thread out of those that have had events. */
3495 random_selector
= (int)
3496 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3498 if (debug_infrun
&& num_events
> 1)
3499 fprintf_unfiltered (gdb_stdlog
,
3500 "infrun: Found %d events, selecting #%d\n",
3501 num_events
, random_selector
);
3503 /* Select the Nth thread that has had an event. */
3504 ALL_NON_EXITED_THREADS (event_tp
)
3505 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3506 && event_tp
->resumed
3507 && event_tp
->suspend
.waitstatus_pending_p
)
3508 if (random_selector
-- == 0)
3514 /* Wrapper for target_wait that first checks whether threads have
3515 pending statuses to report before actually asking the target for
3519 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3522 struct thread_info
*tp
;
3524 /* First check if there is a resumed thread with a wait status
3526 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3528 tp
= random_pending_event_thread (ptid
);
3533 fprintf_unfiltered (gdb_stdlog
,
3534 "infrun: Waiting for specific thread %s.\n",
3535 target_pid_to_str (ptid
));
3537 /* We have a specific thread to check. */
3538 tp
= find_thread_ptid (ptid
);
3539 gdb_assert (tp
!= NULL
);
3540 if (!tp
->suspend
.waitstatus_pending_p
)
3545 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3546 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3548 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3549 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3553 pc
= regcache_read_pc (regcache
);
3555 if (pc
!= tp
->suspend
.stop_pc
)
3558 fprintf_unfiltered (gdb_stdlog
,
3559 "infrun: PC of %s changed. was=%s, now=%s\n",
3560 target_pid_to_str (tp
->ptid
),
3561 paddress (gdbarch
, tp
->prev_pc
),
3562 paddress (gdbarch
, pc
));
3565 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3568 fprintf_unfiltered (gdb_stdlog
,
3569 "infrun: previous breakpoint of %s, at %s gone\n",
3570 target_pid_to_str (tp
->ptid
),
3571 paddress (gdbarch
, pc
));
3579 fprintf_unfiltered (gdb_stdlog
,
3580 "infrun: pending event of %s cancelled.\n",
3581 target_pid_to_str (tp
->ptid
));
3583 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3584 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3594 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3595 fprintf_unfiltered (gdb_stdlog
,
3596 "infrun: Using pending wait status %s for %s.\n",
3598 target_pid_to_str (tp
->ptid
));
3602 /* Now that we've selected our final event LWP, un-adjust its PC
3603 if it was a software breakpoint (and the target doesn't
3604 always adjust the PC itself). */
3605 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3606 && !target_supports_stopped_by_sw_breakpoint ())
3608 struct regcache
*regcache
;
3609 struct gdbarch
*gdbarch
;
3612 regcache
= get_thread_regcache (tp
->ptid
);
3613 gdbarch
= get_regcache_arch (regcache
);
3615 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3620 pc
= regcache_read_pc (regcache
);
3621 regcache_write_pc (regcache
, pc
+ decr_pc
);
3625 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3626 *status
= tp
->suspend
.waitstatus
;
3627 tp
->suspend
.waitstatus_pending_p
= 0;
3629 /* Wake up the event loop again, until all pending events are
3631 if (target_is_async_p ())
3632 mark_async_event_handler (infrun_async_inferior_event_token
);
3636 /* But if we don't find one, we'll have to wait. */
3638 if (deprecated_target_wait_hook
)
3639 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3641 event_ptid
= target_wait (ptid
, status
, options
);
3646 /* Prepare and stabilize the inferior for detaching it. E.g.,
3647 detaching while a thread is displaced stepping is a recipe for
3648 crashing it, as nothing would readjust the PC out of the scratch
3652 prepare_for_detach (void)
3654 struct inferior
*inf
= current_inferior ();
3655 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3656 struct cleanup
*old_chain_1
;
3657 struct displaced_step_inferior_state
*displaced
;
3659 displaced
= get_displaced_stepping_state (inf
->pid
);
3661 /* Is any thread of this process displaced stepping? If not,
3662 there's nothing else to do. */
3663 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3667 fprintf_unfiltered (gdb_stdlog
,
3668 "displaced-stepping in-process while detaching");
3670 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3673 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3675 struct cleanup
*old_chain_2
;
3676 struct execution_control_state ecss
;
3677 struct execution_control_state
*ecs
;
3680 memset (ecs
, 0, sizeof (*ecs
));
3682 overlay_cache_invalid
= 1;
3683 /* Flush target cache before starting to handle each event.
3684 Target was running and cache could be stale. This is just a
3685 heuristic. Running threads may modify target memory, but we
3686 don't get any event. */
3687 target_dcache_invalidate ();
3689 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3692 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3694 /* If an error happens while handling the event, propagate GDB's
3695 knowledge of the executing state to the frontend/user running
3697 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3700 /* Now figure out what to do with the result of the result. */
3701 handle_inferior_event (ecs
);
3703 /* No error, don't finish the state yet. */
3704 discard_cleanups (old_chain_2
);
3706 /* Breakpoints and watchpoints are not installed on the target
3707 at this point, and signals are passed directly to the
3708 inferior, so this must mean the process is gone. */
3709 if (!ecs
->wait_some_more
)
3711 discard_cleanups (old_chain_1
);
3712 error (_("Program exited while detaching"));
3716 discard_cleanups (old_chain_1
);
3719 /* Wait for control to return from inferior to debugger.
3721 If inferior gets a signal, we may decide to start it up again
3722 instead of returning. That is why there is a loop in this function.
3723 When this function actually returns it means the inferior
3724 should be left stopped and GDB should read more commands. */
3727 wait_for_inferior (void)
3729 struct cleanup
*old_cleanups
;
3730 struct cleanup
*thread_state_chain
;
3734 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3737 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3740 /* If an error happens while handling the event, propagate GDB's
3741 knowledge of the executing state to the frontend/user running
3743 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3747 struct execution_control_state ecss
;
3748 struct execution_control_state
*ecs
= &ecss
;
3749 ptid_t waiton_ptid
= minus_one_ptid
;
3751 memset (ecs
, 0, sizeof (*ecs
));
3753 overlay_cache_invalid
= 1;
3755 /* Flush target cache before starting to handle each event.
3756 Target was running and cache could be stale. This is just a
3757 heuristic. Running threads may modify target memory, but we
3758 don't get any event. */
3759 target_dcache_invalidate ();
3761 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3764 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3766 /* Now figure out what to do with the result of the result. */
3767 handle_inferior_event (ecs
);
3769 if (!ecs
->wait_some_more
)
3773 /* No error, don't finish the state yet. */
3774 discard_cleanups (thread_state_chain
);
3776 do_cleanups (old_cleanups
);
3779 /* Cleanup that reinstalls the readline callback handler, if the
3780 target is running in the background. If while handling the target
3781 event something triggered a secondary prompt, like e.g., a
3782 pagination prompt, we'll have removed the callback handler (see
3783 gdb_readline_wrapper_line). Need to do this as we go back to the
3784 event loop, ready to process further input. Note this has no
3785 effect if the handler hasn't actually been removed, because calling
3786 rl_callback_handler_install resets the line buffer, thus losing
3790 reinstall_readline_callback_handler_cleanup (void *arg
)
3792 struct ui
*ui
= current_ui
;
3796 /* We're not going back to the top level event loop yet. Don't
3797 install the readline callback, as it'd prep the terminal,
3798 readline-style (raw, noecho) (e.g., --batch). We'll install
3799 it the next time the prompt is displayed, when we're ready
3804 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3805 gdb_rl_callback_handler_reinstall ();
3808 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3809 that's just the event thread. In all-stop, that's all threads. */
3812 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3814 struct thread_info
*thr
= ecs
->event_thread
;
3816 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3817 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3821 ALL_NON_EXITED_THREADS (thr
)
3823 if (thr
->thread_fsm
== NULL
)
3825 if (thr
== ecs
->event_thread
)
3828 switch_to_thread (thr
->ptid
);
3829 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3832 if (ecs
->event_thread
!= NULL
)
3833 switch_to_thread (ecs
->event_thread
->ptid
);
3837 /* Helper for all_uis_check_sync_execution_done that works on the
3841 check_curr_ui_sync_execution_done (void)
3843 struct ui
*ui
= current_ui
;
3845 if (ui
->prompt_state
== PROMPT_NEEDED
3847 && !gdb_in_secondary_prompt_p (ui
))
3849 target_terminal_ours ();
3850 observer_notify_sync_execution_done ();
3851 ui_register_input_event_handler (ui
);
3858 all_uis_check_sync_execution_done (void)
3860 struct switch_thru_all_uis state
;
3862 SWITCH_THRU_ALL_UIS (state
)
3864 check_curr_ui_sync_execution_done ();
3871 all_uis_on_sync_execution_starting (void)
3873 struct switch_thru_all_uis state
;
3875 SWITCH_THRU_ALL_UIS (state
)
3877 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3878 async_disable_stdin ();
3882 /* Asynchronous version of wait_for_inferior. It is called by the
3883 event loop whenever a change of state is detected on the file
3884 descriptor corresponding to the target. It can be called more than
3885 once to complete a single execution command. In such cases we need
3886 to keep the state in a global variable ECSS. If it is the last time
3887 that this function is called for a single execution command, then
3888 report to the user that the inferior has stopped, and do the
3889 necessary cleanups. */
3892 fetch_inferior_event (void *client_data
)
3894 struct execution_control_state ecss
;
3895 struct execution_control_state
*ecs
= &ecss
;
3896 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3897 struct cleanup
*ts_old_chain
;
3899 ptid_t waiton_ptid
= minus_one_ptid
;
3901 memset (ecs
, 0, sizeof (*ecs
));
3903 /* Events are always processed with the main UI as current UI. This
3904 way, warnings, debug output, etc. are always consistently sent to
3905 the main console. */
3906 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3908 /* End up with readline processing input, if necessary. */
3909 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3911 /* We're handling a live event, so make sure we're doing live
3912 debugging. If we're looking at traceframes while the target is
3913 running, we're going to need to get back to that mode after
3914 handling the event. */
3917 make_cleanup_restore_current_traceframe ();
3918 set_current_traceframe (-1);
3922 /* In non-stop mode, the user/frontend should not notice a thread
3923 switch due to internal events. Make sure we reverse to the
3924 user selected thread and frame after handling the event and
3925 running any breakpoint commands. */
3926 make_cleanup_restore_current_thread ();
3928 overlay_cache_invalid
= 1;
3929 /* Flush target cache before starting to handle each event. Target
3930 was running and cache could be stale. This is just a heuristic.
3931 Running threads may modify target memory, but we don't get any
3933 target_dcache_invalidate ();
3935 scoped_restore save_exec_dir
3936 = make_scoped_restore (&execution_direction
, target_execution_direction ());
3938 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3939 target_can_async_p () ? TARGET_WNOHANG
: 0);
3942 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3944 /* If an error happens while handling the event, propagate GDB's
3945 knowledge of the executing state to the frontend/user running
3947 if (!target_is_non_stop_p ())
3948 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3950 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3952 /* Get executed before make_cleanup_restore_current_thread above to apply
3953 still for the thread which has thrown the exception. */
3954 make_bpstat_clear_actions_cleanup ();
3956 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3958 /* Now figure out what to do with the result of the result. */
3959 handle_inferior_event (ecs
);
3961 if (!ecs
->wait_some_more
)
3963 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3964 int should_stop
= 1;
3965 struct thread_info
*thr
= ecs
->event_thread
;
3966 int should_notify_stop
= 1;
3968 delete_just_stopped_threads_infrun_breakpoints ();
3972 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3974 if (thread_fsm
!= NULL
)
3975 should_stop
= thread_fsm_should_stop (thread_fsm
, thr
);
3984 clean_up_just_stopped_threads_fsms (ecs
);
3986 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3989 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
3992 if (should_notify_stop
)
3996 /* We may not find an inferior if this was a process exit. */
3997 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3998 proceeded
= normal_stop ();
4002 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
4009 /* No error, don't finish the thread states yet. */
4010 discard_cleanups (ts_old_chain
);
4012 /* Revert thread and frame. */
4013 do_cleanups (old_chain
);
4015 /* If a UI was in sync execution mode, and now isn't, restore its
4016 prompt (a synchronous execution command has finished, and we're
4017 ready for input). */
4018 all_uis_check_sync_execution_done ();
4021 && exec_done_display_p
4022 && (ptid_equal (inferior_ptid
, null_ptid
)
4023 || !is_running (inferior_ptid
)))
4024 printf_unfiltered (_("completed.\n"));
4027 /* Record the frame and location we're currently stepping through. */
4029 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
4031 struct thread_info
*tp
= inferior_thread ();
4033 tp
->control
.step_frame_id
= get_frame_id (frame
);
4034 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4036 tp
->current_symtab
= sal
.symtab
;
4037 tp
->current_line
= sal
.line
;
4040 /* Clear context switchable stepping state. */
4043 init_thread_stepping_state (struct thread_info
*tss
)
4045 tss
->stepped_breakpoint
= 0;
4046 tss
->stepping_over_breakpoint
= 0;
4047 tss
->stepping_over_watchpoint
= 0;
4048 tss
->step_after_step_resume_breakpoint
= 0;
4051 /* Set the cached copy of the last ptid/waitstatus. */
4054 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
4056 target_last_wait_ptid
= ptid
;
4057 target_last_waitstatus
= status
;
4060 /* Return the cached copy of the last pid/waitstatus returned by
4061 target_wait()/deprecated_target_wait_hook(). The data is actually
4062 cached by handle_inferior_event(), which gets called immediately
4063 after target_wait()/deprecated_target_wait_hook(). */
4066 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
4068 *ptidp
= target_last_wait_ptid
;
4069 *status
= target_last_waitstatus
;
4073 nullify_last_target_wait_ptid (void)
4075 target_last_wait_ptid
= minus_one_ptid
;
4078 /* Switch thread contexts. */
4081 context_switch (ptid_t ptid
)
4083 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4085 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4086 target_pid_to_str (inferior_ptid
));
4087 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4088 target_pid_to_str (ptid
));
4091 switch_to_thread (ptid
);
4094 /* If the target can't tell whether we've hit breakpoints
4095 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4096 check whether that could have been caused by a breakpoint. If so,
4097 adjust the PC, per gdbarch_decr_pc_after_break. */
4100 adjust_pc_after_break (struct thread_info
*thread
,
4101 struct target_waitstatus
*ws
)
4103 struct regcache
*regcache
;
4104 struct gdbarch
*gdbarch
;
4105 struct address_space
*aspace
;
4106 CORE_ADDR breakpoint_pc
, decr_pc
;
4108 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4109 we aren't, just return.
4111 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4112 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4113 implemented by software breakpoints should be handled through the normal
4116 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4117 different signals (SIGILL or SIGEMT for instance), but it is less
4118 clear where the PC is pointing afterwards. It may not match
4119 gdbarch_decr_pc_after_break. I don't know any specific target that
4120 generates these signals at breakpoints (the code has been in GDB since at
4121 least 1992) so I can not guess how to handle them here.
4123 In earlier versions of GDB, a target with
4124 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4125 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4126 target with both of these set in GDB history, and it seems unlikely to be
4127 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4129 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4132 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4135 /* In reverse execution, when a breakpoint is hit, the instruction
4136 under it has already been de-executed. The reported PC always
4137 points at the breakpoint address, so adjusting it further would
4138 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4141 B1 0x08000000 : INSN1
4142 B2 0x08000001 : INSN2
4144 PC -> 0x08000003 : INSN4
4146 Say you're stopped at 0x08000003 as above. Reverse continuing
4147 from that point should hit B2 as below. Reading the PC when the
4148 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4149 been de-executed already.
4151 B1 0x08000000 : INSN1
4152 B2 PC -> 0x08000001 : INSN2
4156 We can't apply the same logic as for forward execution, because
4157 we would wrongly adjust the PC to 0x08000000, since there's a
4158 breakpoint at PC - 1. We'd then report a hit on B1, although
4159 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4161 if (execution_direction
== EXEC_REVERSE
)
4164 /* If the target can tell whether the thread hit a SW breakpoint,
4165 trust it. Targets that can tell also adjust the PC
4167 if (target_supports_stopped_by_sw_breakpoint ())
4170 /* Note that relying on whether a breakpoint is planted in memory to
4171 determine this can fail. E.g,. the breakpoint could have been
4172 removed since. Or the thread could have been told to step an
4173 instruction the size of a breakpoint instruction, and only
4174 _after_ was a breakpoint inserted at its address. */
4176 /* If this target does not decrement the PC after breakpoints, then
4177 we have nothing to do. */
4178 regcache
= get_thread_regcache (thread
->ptid
);
4179 gdbarch
= get_regcache_arch (regcache
);
4181 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4185 aspace
= get_regcache_aspace (regcache
);
4187 /* Find the location where (if we've hit a breakpoint) the
4188 breakpoint would be. */
4189 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4191 /* If the target can't tell whether a software breakpoint triggered,
4192 fallback to figuring it out based on breakpoints we think were
4193 inserted in the target, and on whether the thread was stepped or
4196 /* Check whether there actually is a software breakpoint inserted at
4199 If in non-stop mode, a race condition is possible where we've
4200 removed a breakpoint, but stop events for that breakpoint were
4201 already queued and arrive later. To suppress those spurious
4202 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4203 and retire them after a number of stop events are reported. Note
4204 this is an heuristic and can thus get confused. The real fix is
4205 to get the "stopped by SW BP and needs adjustment" info out of
4206 the target/kernel (and thus never reach here; see above). */
4207 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4208 || (target_is_non_stop_p ()
4209 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4211 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4213 if (record_full_is_used ())
4214 record_full_gdb_operation_disable_set ();
4216 /* When using hardware single-step, a SIGTRAP is reported for both
4217 a completed single-step and a software breakpoint. Need to
4218 differentiate between the two, as the latter needs adjusting
4219 but the former does not.
4221 The SIGTRAP can be due to a completed hardware single-step only if
4222 - we didn't insert software single-step breakpoints
4223 - this thread is currently being stepped
4225 If any of these events did not occur, we must have stopped due
4226 to hitting a software breakpoint, and have to back up to the
4229 As a special case, we could have hardware single-stepped a
4230 software breakpoint. In this case (prev_pc == breakpoint_pc),
4231 we also need to back up to the breakpoint address. */
4233 if (thread_has_single_step_breakpoints_set (thread
)
4234 || !currently_stepping (thread
)
4235 || (thread
->stepped_breakpoint
4236 && thread
->prev_pc
== breakpoint_pc
))
4237 regcache_write_pc (regcache
, breakpoint_pc
);
4239 do_cleanups (old_cleanups
);
4244 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4246 for (frame
= get_prev_frame (frame
);
4248 frame
= get_prev_frame (frame
))
4250 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4252 if (get_frame_type (frame
) != INLINE_FRAME
)
4259 /* Auxiliary function that handles syscall entry/return events.
4260 It returns 1 if the inferior should keep going (and GDB
4261 should ignore the event), or 0 if the event deserves to be
4265 handle_syscall_event (struct execution_control_state
*ecs
)
4267 struct regcache
*regcache
;
4270 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4271 context_switch (ecs
->ptid
);
4273 regcache
= get_thread_regcache (ecs
->ptid
);
4274 syscall_number
= ecs
->ws
.value
.syscall_number
;
4275 stop_pc
= regcache_read_pc (regcache
);
4277 if (catch_syscall_enabled () > 0
4278 && catching_syscall_number (syscall_number
) > 0)
4281 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4284 ecs
->event_thread
->control
.stop_bpstat
4285 = bpstat_stop_status (get_regcache_aspace (regcache
),
4286 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4288 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4290 /* Catchpoint hit. */
4295 /* If no catchpoint triggered for this, then keep going. */
4300 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4303 fill_in_stop_func (struct gdbarch
*gdbarch
,
4304 struct execution_control_state
*ecs
)
4306 if (!ecs
->stop_func_filled_in
)
4308 /* Don't care about return value; stop_func_start and stop_func_name
4309 will both be 0 if it doesn't work. */
4310 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4311 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4312 ecs
->stop_func_start
4313 += gdbarch_deprecated_function_start_offset (gdbarch
);
4315 if (gdbarch_skip_entrypoint_p (gdbarch
))
4316 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4317 ecs
->stop_func_start
);
4319 ecs
->stop_func_filled_in
= 1;
4324 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4326 static enum stop_kind
4327 get_inferior_stop_soon (ptid_t ptid
)
4329 struct inferior
*inf
= find_inferior_ptid (ptid
);
4331 gdb_assert (inf
!= NULL
);
4332 return inf
->control
.stop_soon
;
4335 /* Wait for one event. Store the resulting waitstatus in WS, and
4336 return the event ptid. */
4339 wait_one (struct target_waitstatus
*ws
)
4342 ptid_t wait_ptid
= minus_one_ptid
;
4344 overlay_cache_invalid
= 1;
4346 /* Flush target cache before starting to handle each event.
4347 Target was running and cache could be stale. This is just a
4348 heuristic. Running threads may modify target memory, but we
4349 don't get any event. */
4350 target_dcache_invalidate ();
4352 if (deprecated_target_wait_hook
)
4353 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4355 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4358 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4363 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4364 instead of the current thread. */
4365 #define THREAD_STOPPED_BY(REASON) \
4367 thread_stopped_by_ ## REASON (ptid_t ptid) \
4369 struct cleanup *old_chain; \
4372 old_chain = save_inferior_ptid (); \
4373 inferior_ptid = ptid; \
4375 res = target_stopped_by_ ## REASON (); \
4377 do_cleanups (old_chain); \
4382 /* Generate thread_stopped_by_watchpoint. */
4383 THREAD_STOPPED_BY (watchpoint
)
4384 /* Generate thread_stopped_by_sw_breakpoint. */
4385 THREAD_STOPPED_BY (sw_breakpoint
)
4386 /* Generate thread_stopped_by_hw_breakpoint. */
4387 THREAD_STOPPED_BY (hw_breakpoint
)
4389 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4392 switch_to_thread_cleanup (void *ptid_p
)
4394 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4396 switch_to_thread (ptid
);
4399 /* Save the thread's event and stop reason to process it later. */
4402 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4404 struct regcache
*regcache
;
4405 struct address_space
*aspace
;
4411 statstr
= target_waitstatus_to_string (ws
);
4412 fprintf_unfiltered (gdb_stdlog
,
4413 "infrun: saving status %s for %d.%ld.%ld\n",
4415 ptid_get_pid (tp
->ptid
),
4416 ptid_get_lwp (tp
->ptid
),
4417 ptid_get_tid (tp
->ptid
));
4421 /* Record for later. */
4422 tp
->suspend
.waitstatus
= *ws
;
4423 tp
->suspend
.waitstatus_pending_p
= 1;
4425 regcache
= get_thread_regcache (tp
->ptid
);
4426 aspace
= get_regcache_aspace (regcache
);
4428 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4429 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4431 CORE_ADDR pc
= regcache_read_pc (regcache
);
4433 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4435 if (thread_stopped_by_watchpoint (tp
->ptid
))
4437 tp
->suspend
.stop_reason
4438 = TARGET_STOPPED_BY_WATCHPOINT
;
4440 else if (target_supports_stopped_by_sw_breakpoint ()
4441 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4443 tp
->suspend
.stop_reason
4444 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4446 else if (target_supports_stopped_by_hw_breakpoint ()
4447 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4449 tp
->suspend
.stop_reason
4450 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4452 else if (!target_supports_stopped_by_hw_breakpoint ()
4453 && hardware_breakpoint_inserted_here_p (aspace
,
4456 tp
->suspend
.stop_reason
4457 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4459 else if (!target_supports_stopped_by_sw_breakpoint ()
4460 && software_breakpoint_inserted_here_p (aspace
,
4463 tp
->suspend
.stop_reason
4464 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4466 else if (!thread_has_single_step_breakpoints_set (tp
)
4467 && currently_stepping (tp
))
4469 tp
->suspend
.stop_reason
4470 = TARGET_STOPPED_BY_SINGLE_STEP
;
4475 /* A cleanup that disables thread create/exit events. */
4478 disable_thread_events (void *arg
)
4480 target_thread_events (0);
4486 stop_all_threads (void)
4488 /* We may need multiple passes to discover all threads. */
4492 struct cleanup
*old_chain
;
4494 gdb_assert (target_is_non_stop_p ());
4497 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4499 entry_ptid
= inferior_ptid
;
4500 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4502 target_thread_events (1);
4503 make_cleanup (disable_thread_events
, NULL
);
4505 /* Request threads to stop, and then wait for the stops. Because
4506 threads we already know about can spawn more threads while we're
4507 trying to stop them, and we only learn about new threads when we
4508 update the thread list, do this in a loop, and keep iterating
4509 until two passes find no threads that need to be stopped. */
4510 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4513 fprintf_unfiltered (gdb_stdlog
,
4514 "infrun: stop_all_threads, pass=%d, "
4515 "iterations=%d\n", pass
, iterations
);
4519 struct target_waitstatus ws
;
4521 struct thread_info
*t
;
4523 update_thread_list ();
4525 /* Go through all threads looking for threads that we need
4526 to tell the target to stop. */
4527 ALL_NON_EXITED_THREADS (t
)
4531 /* If already stopping, don't request a stop again.
4532 We just haven't seen the notification yet. */
4533 if (!t
->stop_requested
)
4536 fprintf_unfiltered (gdb_stdlog
,
4537 "infrun: %s executing, "
4539 target_pid_to_str (t
->ptid
));
4540 target_stop (t
->ptid
);
4541 t
->stop_requested
= 1;
4546 fprintf_unfiltered (gdb_stdlog
,
4547 "infrun: %s executing, "
4548 "already stopping\n",
4549 target_pid_to_str (t
->ptid
));
4552 if (t
->stop_requested
)
4558 fprintf_unfiltered (gdb_stdlog
,
4559 "infrun: %s not executing\n",
4560 target_pid_to_str (t
->ptid
));
4562 /* The thread may be not executing, but still be
4563 resumed with a pending status to process. */
4571 /* If we find new threads on the second iteration, restart
4572 over. We want to see two iterations in a row with all
4577 event_ptid
= wait_one (&ws
);
4578 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4580 /* All resumed threads exited. */
4582 else if (ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4583 || ws
.kind
== TARGET_WAITKIND_EXITED
4584 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4588 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4590 fprintf_unfiltered (gdb_stdlog
,
4591 "infrun: %s exited while "
4592 "stopping threads\n",
4593 target_pid_to_str (ptid
));
4598 struct inferior
*inf
;
4600 t
= find_thread_ptid (event_ptid
);
4602 t
= add_thread (event_ptid
);
4604 t
->stop_requested
= 0;
4607 t
->control
.may_range_step
= 0;
4609 /* This may be the first time we see the inferior report
4611 inf
= find_inferior_ptid (event_ptid
);
4612 if (inf
->needs_setup
)
4614 switch_to_thread_no_regs (t
);
4618 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4619 && ws
.value
.sig
== GDB_SIGNAL_0
)
4621 /* We caught the event that we intended to catch, so
4622 there's no event pending. */
4623 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4624 t
->suspend
.waitstatus_pending_p
= 0;
4626 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4628 /* Add it back to the step-over queue. */
4631 fprintf_unfiltered (gdb_stdlog
,
4632 "infrun: displaced-step of %s "
4633 "canceled: adding back to the "
4634 "step-over queue\n",
4635 target_pid_to_str (t
->ptid
));
4637 t
->control
.trap_expected
= 0;
4638 thread_step_over_chain_enqueue (t
);
4643 enum gdb_signal sig
;
4644 struct regcache
*regcache
;
4650 statstr
= target_waitstatus_to_string (&ws
);
4651 fprintf_unfiltered (gdb_stdlog
,
4652 "infrun: target_wait %s, saving "
4653 "status for %d.%ld.%ld\n",
4655 ptid_get_pid (t
->ptid
),
4656 ptid_get_lwp (t
->ptid
),
4657 ptid_get_tid (t
->ptid
));
4661 /* Record for later. */
4662 save_waitstatus (t
, &ws
);
4664 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4665 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4667 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4669 /* Add it back to the step-over queue. */
4670 t
->control
.trap_expected
= 0;
4671 thread_step_over_chain_enqueue (t
);
4674 regcache
= get_thread_regcache (t
->ptid
);
4675 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4679 fprintf_unfiltered (gdb_stdlog
,
4680 "infrun: saved stop_pc=%s for %s "
4681 "(currently_stepping=%d)\n",
4682 paddress (target_gdbarch (),
4683 t
->suspend
.stop_pc
),
4684 target_pid_to_str (t
->ptid
),
4685 currently_stepping (t
));
4692 do_cleanups (old_chain
);
4695 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4698 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4701 handle_no_resumed (struct execution_control_state
*ecs
)
4703 struct inferior
*inf
;
4704 struct thread_info
*thread
;
4706 if (target_can_async_p ())
4713 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4721 /* There were no unwaited-for children left in the target, but,
4722 we're not synchronously waiting for events either. Just
4726 fprintf_unfiltered (gdb_stdlog
,
4727 "infrun: TARGET_WAITKIND_NO_RESUMED "
4728 "(ignoring: bg)\n");
4729 prepare_to_wait (ecs
);
4734 /* Otherwise, if we were running a synchronous execution command, we
4735 may need to cancel it and give the user back the terminal.
4737 In non-stop mode, the target can't tell whether we've already
4738 consumed previous stop events, so it can end up sending us a
4739 no-resumed event like so:
4741 #0 - thread 1 is left stopped
4743 #1 - thread 2 is resumed and hits breakpoint
4744 -> TARGET_WAITKIND_STOPPED
4746 #2 - thread 3 is resumed and exits
4747 this is the last resumed thread, so
4748 -> TARGET_WAITKIND_NO_RESUMED
4750 #3 - gdb processes stop for thread 2 and decides to re-resume
4753 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4754 thread 2 is now resumed, so the event should be ignored.
4756 IOW, if the stop for thread 2 doesn't end a foreground command,
4757 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4758 event. But it could be that the event meant that thread 2 itself
4759 (or whatever other thread was the last resumed thread) exited.
4761 To address this we refresh the thread list and check whether we
4762 have resumed threads _now_. In the example above, this removes
4763 thread 3 from the thread list. If thread 2 was re-resumed, we
4764 ignore this event. If we find no thread resumed, then we cancel
4765 the synchronous command show "no unwaited-for " to the user. */
4766 update_thread_list ();
4768 ALL_NON_EXITED_THREADS (thread
)
4770 if (thread
->executing
4771 || thread
->suspend
.waitstatus_pending_p
)
4773 /* There were no unwaited-for children left in the target at
4774 some point, but there are now. Just ignore. */
4776 fprintf_unfiltered (gdb_stdlog
,
4777 "infrun: TARGET_WAITKIND_NO_RESUMED "
4778 "(ignoring: found resumed)\n");
4779 prepare_to_wait (ecs
);
4784 /* Note however that we may find no resumed thread because the whole
4785 process exited meanwhile (thus updating the thread list results
4786 in an empty thread list). In this case we know we'll be getting
4787 a process exit event shortly. */
4793 thread
= any_live_thread_of_process (inf
->pid
);
4797 fprintf_unfiltered (gdb_stdlog
,
4798 "infrun: TARGET_WAITKIND_NO_RESUMED "
4799 "(expect process exit)\n");
4800 prepare_to_wait (ecs
);
4805 /* Go ahead and report the event. */
4809 /* Given an execution control state that has been freshly filled in by
4810 an event from the inferior, figure out what it means and take
4813 The alternatives are:
4815 1) stop_waiting and return; to really stop and return to the
4818 2) keep_going and return; to wait for the next event (set
4819 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4823 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4825 enum stop_kind stop_soon
;
4827 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4829 /* We had an event in the inferior, but we are not interested in
4830 handling it at this level. The lower layers have already
4831 done what needs to be done, if anything.
4833 One of the possible circumstances for this is when the
4834 inferior produces output for the console. The inferior has
4835 not stopped, and we are ignoring the event. Another possible
4836 circumstance is any event which the lower level knows will be
4837 reported multiple times without an intervening resume. */
4839 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4840 prepare_to_wait (ecs
);
4844 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4847 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4848 prepare_to_wait (ecs
);
4852 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4853 && handle_no_resumed (ecs
))
4856 /* Cache the last pid/waitstatus. */
4857 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4859 /* Always clear state belonging to the previous time we stopped. */
4860 stop_stack_dummy
= STOP_NONE
;
4862 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4864 /* No unwaited-for children left. IOW, all resumed children
4867 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4869 stop_print_frame
= 0;
4874 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4875 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4877 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4878 /* If it's a new thread, add it to the thread database. */
4879 if (ecs
->event_thread
== NULL
)
4880 ecs
->event_thread
= add_thread (ecs
->ptid
);
4882 /* Disable range stepping. If the next step request could use a
4883 range, this will be end up re-enabled then. */
4884 ecs
->event_thread
->control
.may_range_step
= 0;
4887 /* Dependent on valid ECS->EVENT_THREAD. */
4888 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4890 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4891 reinit_frame_cache ();
4893 breakpoint_retire_moribund ();
4895 /* First, distinguish signals caused by the debugger from signals
4896 that have to do with the program's own actions. Note that
4897 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4898 on the operating system version. Here we detect when a SIGILL or
4899 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4900 something similar for SIGSEGV, since a SIGSEGV will be generated
4901 when we're trying to execute a breakpoint instruction on a
4902 non-executable stack. This happens for call dummy breakpoints
4903 for architectures like SPARC that place call dummies on the
4905 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4906 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4907 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4908 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4910 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4912 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4913 regcache_read_pc (regcache
)))
4916 fprintf_unfiltered (gdb_stdlog
,
4917 "infrun: Treating signal as SIGTRAP\n");
4918 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4922 /* Mark the non-executing threads accordingly. In all-stop, all
4923 threads of all processes are stopped when we get any event
4924 reported. In non-stop mode, only the event thread stops. */
4928 if (!target_is_non_stop_p ())
4929 mark_ptid
= minus_one_ptid
;
4930 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4931 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4933 /* If we're handling a process exit in non-stop mode, even
4934 though threads haven't been deleted yet, one would think
4935 that there is nothing to do, as threads of the dead process
4936 will be soon deleted, and threads of any other process were
4937 left running. However, on some targets, threads survive a
4938 process exit event. E.g., for the "checkpoint" command,
4939 when the current checkpoint/fork exits, linux-fork.c
4940 automatically switches to another fork from within
4941 target_mourn_inferior, by associating the same
4942 inferior/thread to another fork. We haven't mourned yet at
4943 this point, but we must mark any threads left in the
4944 process as not-executing so that finish_thread_state marks
4945 them stopped (in the user's perspective) if/when we present
4946 the stop to the user. */
4947 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4950 mark_ptid
= ecs
->ptid
;
4952 set_executing (mark_ptid
, 0);
4954 /* Likewise the resumed flag. */
4955 set_resumed (mark_ptid
, 0);
4958 switch (ecs
->ws
.kind
)
4960 case TARGET_WAITKIND_LOADED
:
4962 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4963 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4964 context_switch (ecs
->ptid
);
4965 /* Ignore gracefully during startup of the inferior, as it might
4966 be the shell which has just loaded some objects, otherwise
4967 add the symbols for the newly loaded objects. Also ignore at
4968 the beginning of an attach or remote session; we will query
4969 the full list of libraries once the connection is
4972 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4973 if (stop_soon
== NO_STOP_QUIETLY
)
4975 struct regcache
*regcache
;
4977 regcache
= get_thread_regcache (ecs
->ptid
);
4979 handle_solib_event ();
4981 ecs
->event_thread
->control
.stop_bpstat
4982 = bpstat_stop_status (get_regcache_aspace (regcache
),
4983 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4985 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4987 /* A catchpoint triggered. */
4988 process_event_stop_test (ecs
);
4992 /* If requested, stop when the dynamic linker notifies
4993 gdb of events. This allows the user to get control
4994 and place breakpoints in initializer routines for
4995 dynamically loaded objects (among other things). */
4996 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4997 if (stop_on_solib_events
)
4999 /* Make sure we print "Stopped due to solib-event" in
5001 stop_print_frame
= 1;
5008 /* If we are skipping through a shell, or through shared library
5009 loading that we aren't interested in, resume the program. If
5010 we're running the program normally, also resume. */
5011 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5013 /* Loading of shared libraries might have changed breakpoint
5014 addresses. Make sure new breakpoints are inserted. */
5015 if (stop_soon
== NO_STOP_QUIETLY
)
5016 insert_breakpoints ();
5017 resume (GDB_SIGNAL_0
);
5018 prepare_to_wait (ecs
);
5022 /* But stop if we're attaching or setting up a remote
5024 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5025 || stop_soon
== STOP_QUIETLY_REMOTE
)
5028 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5033 internal_error (__FILE__
, __LINE__
,
5034 _("unhandled stop_soon: %d"), (int) stop_soon
);
5036 case TARGET_WAITKIND_SPURIOUS
:
5038 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5039 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5040 context_switch (ecs
->ptid
);
5041 resume (GDB_SIGNAL_0
);
5042 prepare_to_wait (ecs
);
5045 case TARGET_WAITKIND_THREAD_CREATED
:
5047 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5048 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5049 context_switch (ecs
->ptid
);
5050 if (!switch_back_to_stepped_thread (ecs
))
5054 case TARGET_WAITKIND_EXITED
:
5055 case TARGET_WAITKIND_SIGNALLED
:
5058 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5059 fprintf_unfiltered (gdb_stdlog
,
5060 "infrun: TARGET_WAITKIND_EXITED\n");
5062 fprintf_unfiltered (gdb_stdlog
,
5063 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5066 inferior_ptid
= ecs
->ptid
;
5067 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
5068 set_current_program_space (current_inferior ()->pspace
);
5069 handle_vfork_child_exec_or_exit (0);
5070 target_terminal_ours (); /* Must do this before mourn anyway. */
5072 /* Clearing any previous state of convenience variables. */
5073 clear_exit_convenience_vars ();
5075 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5077 /* Record the exit code in the convenience variable $_exitcode, so
5078 that the user can inspect this again later. */
5079 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5080 (LONGEST
) ecs
->ws
.value
.integer
);
5082 /* Also record this in the inferior itself. */
5083 current_inferior ()->has_exit_code
= 1;
5084 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5086 /* Support the --return-child-result option. */
5087 return_child_result_value
= ecs
->ws
.value
.integer
;
5089 observer_notify_exited (ecs
->ws
.value
.integer
);
5093 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5094 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5096 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5098 /* Set the value of the internal variable $_exitsignal,
5099 which holds the signal uncaught by the inferior. */
5100 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5101 gdbarch_gdb_signal_to_target (gdbarch
,
5102 ecs
->ws
.value
.sig
));
5106 /* We don't have access to the target's method used for
5107 converting between signal numbers (GDB's internal
5108 representation <-> target's representation).
5109 Therefore, we cannot do a good job at displaying this
5110 information to the user. It's better to just warn
5111 her about it (if infrun debugging is enabled), and
5114 fprintf_filtered (gdb_stdlog
, _("\
5115 Cannot fill $_exitsignal with the correct signal number.\n"));
5118 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
5121 gdb_flush (gdb_stdout
);
5122 target_mourn_inferior (inferior_ptid
);
5123 stop_print_frame
= 0;
5127 /* The following are the only cases in which we keep going;
5128 the above cases end in a continue or goto. */
5129 case TARGET_WAITKIND_FORKED
:
5130 case TARGET_WAITKIND_VFORKED
:
5133 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5134 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
5136 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
5139 /* Check whether the inferior is displaced stepping. */
5141 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5142 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5144 /* If checking displaced stepping is supported, and thread
5145 ecs->ptid is displaced stepping. */
5146 if (displaced_step_in_progress_thread (ecs
->ptid
))
5148 struct inferior
*parent_inf
5149 = find_inferior_ptid (ecs
->ptid
);
5150 struct regcache
*child_regcache
;
5151 CORE_ADDR parent_pc
;
5153 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5154 indicating that the displaced stepping of syscall instruction
5155 has been done. Perform cleanup for parent process here. Note
5156 that this operation also cleans up the child process for vfork,
5157 because their pages are shared. */
5158 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
5159 /* Start a new step-over in another thread if there's one
5163 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5165 struct displaced_step_inferior_state
*displaced
5166 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
5168 /* Restore scratch pad for child process. */
5169 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
5172 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5173 the child's PC is also within the scratchpad. Set the child's PC
5174 to the parent's PC value, which has already been fixed up.
5175 FIXME: we use the parent's aspace here, although we're touching
5176 the child, because the child hasn't been added to the inferior
5177 list yet at this point. */
5180 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
5182 parent_inf
->aspace
);
5183 /* Read PC value of parent process. */
5184 parent_pc
= regcache_read_pc (regcache
);
5186 if (debug_displaced
)
5187 fprintf_unfiltered (gdb_stdlog
,
5188 "displaced: write child pc from %s to %s\n",
5190 regcache_read_pc (child_regcache
)),
5191 paddress (gdbarch
, parent_pc
));
5193 regcache_write_pc (child_regcache
, parent_pc
);
5197 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5198 context_switch (ecs
->ptid
);
5200 /* Immediately detach breakpoints from the child before there's
5201 any chance of letting the user delete breakpoints from the
5202 breakpoint lists. If we don't do this early, it's easy to
5203 leave left over traps in the child, vis: "break foo; catch
5204 fork; c; <fork>; del; c; <child calls foo>". We only follow
5205 the fork on the last `continue', and by that time the
5206 breakpoint at "foo" is long gone from the breakpoint table.
5207 If we vforked, then we don't need to unpatch here, since both
5208 parent and child are sharing the same memory pages; we'll
5209 need to unpatch at follow/detach time instead to be certain
5210 that new breakpoints added between catchpoint hit time and
5211 vfork follow are detached. */
5212 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5214 /* This won't actually modify the breakpoint list, but will
5215 physically remove the breakpoints from the child. */
5216 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5219 delete_just_stopped_threads_single_step_breakpoints ();
5221 /* In case the event is caught by a catchpoint, remember that
5222 the event is to be followed at the next resume of the thread,
5223 and not immediately. */
5224 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5226 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5228 ecs
->event_thread
->control
.stop_bpstat
5229 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5230 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5232 /* If no catchpoint triggered for this, then keep going. Note
5233 that we're interested in knowing the bpstat actually causes a
5234 stop, not just if it may explain the signal. Software
5235 watchpoints, for example, always appear in the bpstat. */
5236 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5242 = (follow_fork_mode_string
== follow_fork_mode_child
);
5244 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5246 should_resume
= follow_fork ();
5249 child
= ecs
->ws
.value
.related_pid
;
5251 /* At this point, the parent is marked running, and the
5252 child is marked stopped. */
5254 /* If not resuming the parent, mark it stopped. */
5255 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5256 set_running (parent
, 0);
5258 /* If resuming the child, mark it running. */
5259 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5260 set_running (child
, 1);
5262 /* In non-stop mode, also resume the other branch. */
5263 if (!detach_fork
&& (non_stop
5264 || (sched_multi
&& target_is_non_stop_p ())))
5267 switch_to_thread (parent
);
5269 switch_to_thread (child
);
5271 ecs
->event_thread
= inferior_thread ();
5272 ecs
->ptid
= inferior_ptid
;
5277 switch_to_thread (child
);
5279 switch_to_thread (parent
);
5281 ecs
->event_thread
= inferior_thread ();
5282 ecs
->ptid
= inferior_ptid
;
5290 process_event_stop_test (ecs
);
5293 case TARGET_WAITKIND_VFORK_DONE
:
5294 /* Done with the shared memory region. Re-insert breakpoints in
5295 the parent, and keep going. */
5298 fprintf_unfiltered (gdb_stdlog
,
5299 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5301 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5302 context_switch (ecs
->ptid
);
5304 current_inferior ()->waiting_for_vfork_done
= 0;
5305 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5306 /* This also takes care of reinserting breakpoints in the
5307 previously locked inferior. */
5311 case TARGET_WAITKIND_EXECD
:
5313 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5315 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5316 context_switch (ecs
->ptid
);
5318 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5320 /* Do whatever is necessary to the parent branch of the vfork. */
5321 handle_vfork_child_exec_or_exit (1);
5323 /* This causes the eventpoints and symbol table to be reset.
5324 Must do this now, before trying to determine whether to
5326 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5328 /* In follow_exec we may have deleted the original thread and
5329 created a new one. Make sure that the event thread is the
5330 execd thread for that case (this is a nop otherwise). */
5331 ecs
->event_thread
= inferior_thread ();
5333 ecs
->event_thread
->control
.stop_bpstat
5334 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5335 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5337 /* Note that this may be referenced from inside
5338 bpstat_stop_status above, through inferior_has_execd. */
5339 xfree (ecs
->ws
.value
.execd_pathname
);
5340 ecs
->ws
.value
.execd_pathname
= NULL
;
5342 /* If no catchpoint triggered for this, then keep going. */
5343 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5345 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5349 process_event_stop_test (ecs
);
5352 /* Be careful not to try to gather much state about a thread
5353 that's in a syscall. It's frequently a losing proposition. */
5354 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5356 fprintf_unfiltered (gdb_stdlog
,
5357 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5358 /* Getting the current syscall number. */
5359 if (handle_syscall_event (ecs
) == 0)
5360 process_event_stop_test (ecs
);
5363 /* Before examining the threads further, step this thread to
5364 get it entirely out of the syscall. (We get notice of the
5365 event when the thread is just on the verge of exiting a
5366 syscall. Stepping one instruction seems to get it back
5368 case TARGET_WAITKIND_SYSCALL_RETURN
:
5370 fprintf_unfiltered (gdb_stdlog
,
5371 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5372 if (handle_syscall_event (ecs
) == 0)
5373 process_event_stop_test (ecs
);
5376 case TARGET_WAITKIND_STOPPED
:
5378 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5379 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5380 handle_signal_stop (ecs
);
5383 case TARGET_WAITKIND_NO_HISTORY
:
5385 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5386 /* Reverse execution: target ran out of history info. */
5388 /* Switch to the stopped thread. */
5389 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5390 context_switch (ecs
->ptid
);
5392 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5394 delete_just_stopped_threads_single_step_breakpoints ();
5395 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5396 observer_notify_no_history ();
5402 /* A wrapper around handle_inferior_event_1, which also makes sure
5403 that all temporary struct value objects that were created during
5404 the handling of the event get deleted at the end. */
5407 handle_inferior_event (struct execution_control_state
*ecs
)
5409 struct value
*mark
= value_mark ();
5411 handle_inferior_event_1 (ecs
);
5412 /* Purge all temporary values created during the event handling,
5413 as it could be a long time before we return to the command level
5414 where such values would otherwise be purged. */
5415 value_free_to_mark (mark
);
5418 /* Restart threads back to what they were trying to do back when we
5419 paused them for an in-line step-over. The EVENT_THREAD thread is
5423 restart_threads (struct thread_info
*event_thread
)
5425 struct thread_info
*tp
;
5427 /* In case the instruction just stepped spawned a new thread. */
5428 update_thread_list ();
5430 ALL_NON_EXITED_THREADS (tp
)
5432 if (tp
== event_thread
)
5435 fprintf_unfiltered (gdb_stdlog
,
5436 "infrun: restart threads: "
5437 "[%s] is event thread\n",
5438 target_pid_to_str (tp
->ptid
));
5442 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5445 fprintf_unfiltered (gdb_stdlog
,
5446 "infrun: restart threads: "
5447 "[%s] not meant to be running\n",
5448 target_pid_to_str (tp
->ptid
));
5455 fprintf_unfiltered (gdb_stdlog
,
5456 "infrun: restart threads: [%s] resumed\n",
5457 target_pid_to_str (tp
->ptid
));
5458 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5462 if (thread_is_in_step_over_chain (tp
))
5465 fprintf_unfiltered (gdb_stdlog
,
5466 "infrun: restart threads: "
5467 "[%s] needs step-over\n",
5468 target_pid_to_str (tp
->ptid
));
5469 gdb_assert (!tp
->resumed
);
5474 if (tp
->suspend
.waitstatus_pending_p
)
5477 fprintf_unfiltered (gdb_stdlog
,
5478 "infrun: restart threads: "
5479 "[%s] has pending status\n",
5480 target_pid_to_str (tp
->ptid
));
5485 /* If some thread needs to start a step-over at this point, it
5486 should still be in the step-over queue, and thus skipped
5488 if (thread_still_needs_step_over (tp
))
5490 internal_error (__FILE__
, __LINE__
,
5491 "thread [%s] needs a step-over, but not in "
5492 "step-over queue\n",
5493 target_pid_to_str (tp
->ptid
));
5496 if (currently_stepping (tp
))
5499 fprintf_unfiltered (gdb_stdlog
,
5500 "infrun: restart threads: [%s] was stepping\n",
5501 target_pid_to_str (tp
->ptid
));
5502 keep_going_stepped_thread (tp
);
5506 struct execution_control_state ecss
;
5507 struct execution_control_state
*ecs
= &ecss
;
5510 fprintf_unfiltered (gdb_stdlog
,
5511 "infrun: restart threads: [%s] continuing\n",
5512 target_pid_to_str (tp
->ptid
));
5513 reset_ecs (ecs
, tp
);
5514 switch_to_thread (tp
->ptid
);
5515 keep_going_pass_signal (ecs
);
5520 /* Callback for iterate_over_threads. Find a resumed thread that has
5521 a pending waitstatus. */
5524 resumed_thread_with_pending_status (struct thread_info
*tp
,
5528 && tp
->suspend
.waitstatus_pending_p
);
5531 /* Called when we get an event that may finish an in-line or
5532 out-of-line (displaced stepping) step-over started previously.
5533 Return true if the event is processed and we should go back to the
5534 event loop; false if the caller should continue processing the
5538 finish_step_over (struct execution_control_state
*ecs
)
5540 int had_step_over_info
;
5542 displaced_step_fixup (ecs
->ptid
,
5543 ecs
->event_thread
->suspend
.stop_signal
);
5545 had_step_over_info
= step_over_info_valid_p ();
5547 if (had_step_over_info
)
5549 /* If we're stepping over a breakpoint with all threads locked,
5550 then only the thread that was stepped should be reporting
5552 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5554 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5555 clear_step_over_info ();
5558 if (!target_is_non_stop_p ())
5561 /* Start a new step-over in another thread if there's one that
5565 /* If we were stepping over a breakpoint before, and haven't started
5566 a new in-line step-over sequence, then restart all other threads
5567 (except the event thread). We can't do this in all-stop, as then
5568 e.g., we wouldn't be able to issue any other remote packet until
5569 these other threads stop. */
5570 if (had_step_over_info
&& !step_over_info_valid_p ())
5572 struct thread_info
*pending
;
5574 /* If we only have threads with pending statuses, the restart
5575 below won't restart any thread and so nothing re-inserts the
5576 breakpoint we just stepped over. But we need it inserted
5577 when we later process the pending events, otherwise if
5578 another thread has a pending event for this breakpoint too,
5579 we'd discard its event (because the breakpoint that
5580 originally caused the event was no longer inserted). */
5581 context_switch (ecs
->ptid
);
5582 insert_breakpoints ();
5584 restart_threads (ecs
->event_thread
);
5586 /* If we have events pending, go through handle_inferior_event
5587 again, picking up a pending event at random. This avoids
5588 thread starvation. */
5590 /* But not if we just stepped over a watchpoint in order to let
5591 the instruction execute so we can evaluate its expression.
5592 The set of watchpoints that triggered is recorded in the
5593 breakpoint objects themselves (see bp->watchpoint_triggered).
5594 If we processed another event first, that other event could
5595 clobber this info. */
5596 if (ecs
->event_thread
->stepping_over_watchpoint
)
5599 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5601 if (pending
!= NULL
)
5603 struct thread_info
*tp
= ecs
->event_thread
;
5604 struct regcache
*regcache
;
5608 fprintf_unfiltered (gdb_stdlog
,
5609 "infrun: found resumed threads with "
5610 "pending events, saving status\n");
5613 gdb_assert (pending
!= tp
);
5615 /* Record the event thread's event for later. */
5616 save_waitstatus (tp
, &ecs
->ws
);
5617 /* This was cleared early, by handle_inferior_event. Set it
5618 so this pending event is considered by
5622 gdb_assert (!tp
->executing
);
5624 regcache
= get_thread_regcache (tp
->ptid
);
5625 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5629 fprintf_unfiltered (gdb_stdlog
,
5630 "infrun: saved stop_pc=%s for %s "
5631 "(currently_stepping=%d)\n",
5632 paddress (target_gdbarch (),
5633 tp
->suspend
.stop_pc
),
5634 target_pid_to_str (tp
->ptid
),
5635 currently_stepping (tp
));
5638 /* This in-line step-over finished; clear this so we won't
5639 start a new one. This is what handle_signal_stop would
5640 do, if we returned false. */
5641 tp
->stepping_over_breakpoint
= 0;
5643 /* Wake up the event loop again. */
5644 mark_async_event_handler (infrun_async_inferior_event_token
);
5646 prepare_to_wait (ecs
);
5654 /* Come here when the program has stopped with a signal. */
5657 handle_signal_stop (struct execution_control_state
*ecs
)
5659 struct frame_info
*frame
;
5660 struct gdbarch
*gdbarch
;
5661 int stopped_by_watchpoint
;
5662 enum stop_kind stop_soon
;
5665 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5667 /* Do we need to clean up the state of a thread that has
5668 completed a displaced single-step? (Doing so usually affects
5669 the PC, so do it here, before we set stop_pc.) */
5670 if (finish_step_over (ecs
))
5673 /* If we either finished a single-step or hit a breakpoint, but
5674 the user wanted this thread to be stopped, pretend we got a
5675 SIG0 (generic unsignaled stop). */
5676 if (ecs
->event_thread
->stop_requested
5677 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5678 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5680 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5684 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5685 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5686 struct cleanup
*old_chain
= save_inferior_ptid ();
5688 inferior_ptid
= ecs
->ptid
;
5690 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5691 paddress (gdbarch
, stop_pc
));
5692 if (target_stopped_by_watchpoint ())
5696 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5698 if (target_stopped_data_address (¤t_target
, &addr
))
5699 fprintf_unfiltered (gdb_stdlog
,
5700 "infrun: stopped data address = %s\n",
5701 paddress (gdbarch
, addr
));
5703 fprintf_unfiltered (gdb_stdlog
,
5704 "infrun: (no data address available)\n");
5707 do_cleanups (old_chain
);
5710 /* This is originated from start_remote(), start_inferior() and
5711 shared libraries hook functions. */
5712 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5713 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5715 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5716 context_switch (ecs
->ptid
);
5718 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5719 stop_print_frame
= 1;
5724 /* This originates from attach_command(). We need to overwrite
5725 the stop_signal here, because some kernels don't ignore a
5726 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5727 See more comments in inferior.h. On the other hand, if we
5728 get a non-SIGSTOP, report it to the user - assume the backend
5729 will handle the SIGSTOP if it should show up later.
5731 Also consider that the attach is complete when we see a
5732 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5733 target extended-remote report it instead of a SIGSTOP
5734 (e.g. gdbserver). We already rely on SIGTRAP being our
5735 signal, so this is no exception.
5737 Also consider that the attach is complete when we see a
5738 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5739 the target to stop all threads of the inferior, in case the
5740 low level attach operation doesn't stop them implicitly. If
5741 they weren't stopped implicitly, then the stub will report a
5742 GDB_SIGNAL_0, meaning: stopped for no particular reason
5743 other than GDB's request. */
5744 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5745 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5746 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5747 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5749 stop_print_frame
= 1;
5751 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5755 /* See if something interesting happened to the non-current thread. If
5756 so, then switch to that thread. */
5757 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5760 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5762 context_switch (ecs
->ptid
);
5764 if (deprecated_context_hook
)
5765 deprecated_context_hook (ptid_to_global_thread_id (ecs
->ptid
));
5768 /* At this point, get hold of the now-current thread's frame. */
5769 frame
= get_current_frame ();
5770 gdbarch
= get_frame_arch (frame
);
5772 /* Pull the single step breakpoints out of the target. */
5773 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5775 struct regcache
*regcache
;
5776 struct address_space
*aspace
;
5779 regcache
= get_thread_regcache (ecs
->ptid
);
5780 aspace
= get_regcache_aspace (regcache
);
5781 pc
= regcache_read_pc (regcache
);
5783 /* However, before doing so, if this single-step breakpoint was
5784 actually for another thread, set this thread up for moving
5786 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5789 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5793 fprintf_unfiltered (gdb_stdlog
,
5794 "infrun: [%s] hit another thread's "
5795 "single-step breakpoint\n",
5796 target_pid_to_str (ecs
->ptid
));
5798 ecs
->hit_singlestep_breakpoint
= 1;
5805 fprintf_unfiltered (gdb_stdlog
,
5806 "infrun: [%s] hit its "
5807 "single-step breakpoint\n",
5808 target_pid_to_str (ecs
->ptid
));
5812 delete_just_stopped_threads_single_step_breakpoints ();
5814 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5815 && ecs
->event_thread
->control
.trap_expected
5816 && ecs
->event_thread
->stepping_over_watchpoint
)
5817 stopped_by_watchpoint
= 0;
5819 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5821 /* If necessary, step over this watchpoint. We'll be back to display
5823 if (stopped_by_watchpoint
5824 && (target_have_steppable_watchpoint
5825 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5827 /* At this point, we are stopped at an instruction which has
5828 attempted to write to a piece of memory under control of
5829 a watchpoint. The instruction hasn't actually executed
5830 yet. If we were to evaluate the watchpoint expression
5831 now, we would get the old value, and therefore no change
5832 would seem to have occurred.
5834 In order to make watchpoints work `right', we really need
5835 to complete the memory write, and then evaluate the
5836 watchpoint expression. We do this by single-stepping the
5839 It may not be necessary to disable the watchpoint to step over
5840 it. For example, the PA can (with some kernel cooperation)
5841 single step over a watchpoint without disabling the watchpoint.
5843 It is far more common to need to disable a watchpoint to step
5844 the inferior over it. If we have non-steppable watchpoints,
5845 we must disable the current watchpoint; it's simplest to
5846 disable all watchpoints.
5848 Any breakpoint at PC must also be stepped over -- if there's
5849 one, it will have already triggered before the watchpoint
5850 triggered, and we either already reported it to the user, or
5851 it didn't cause a stop and we called keep_going. In either
5852 case, if there was a breakpoint at PC, we must be trying to
5854 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5859 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5860 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5861 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5862 ecs
->event_thread
->control
.stop_step
= 0;
5863 stop_print_frame
= 1;
5864 stopped_by_random_signal
= 0;
5866 /* Hide inlined functions starting here, unless we just performed stepi or
5867 nexti. After stepi and nexti, always show the innermost frame (not any
5868 inline function call sites). */
5869 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5871 struct address_space
*aspace
=
5872 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5874 /* skip_inline_frames is expensive, so we avoid it if we can
5875 determine that the address is one where functions cannot have
5876 been inlined. This improves performance with inferiors that
5877 load a lot of shared libraries, because the solib event
5878 breakpoint is defined as the address of a function (i.e. not
5879 inline). Note that we have to check the previous PC as well
5880 as the current one to catch cases when we have just
5881 single-stepped off a breakpoint prior to reinstating it.
5882 Note that we're assuming that the code we single-step to is
5883 not inline, but that's not definitive: there's nothing
5884 preventing the event breakpoint function from containing
5885 inlined code, and the single-step ending up there. If the
5886 user had set a breakpoint on that inlined code, the missing
5887 skip_inline_frames call would break things. Fortunately
5888 that's an extremely unlikely scenario. */
5889 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5890 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5891 && ecs
->event_thread
->control
.trap_expected
5892 && pc_at_non_inline_function (aspace
,
5893 ecs
->event_thread
->prev_pc
,
5896 skip_inline_frames (ecs
->ptid
);
5898 /* Re-fetch current thread's frame in case that invalidated
5900 frame
= get_current_frame ();
5901 gdbarch
= get_frame_arch (frame
);
5905 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5906 && ecs
->event_thread
->control
.trap_expected
5907 && gdbarch_single_step_through_delay_p (gdbarch
)
5908 && currently_stepping (ecs
->event_thread
))
5910 /* We're trying to step off a breakpoint. Turns out that we're
5911 also on an instruction that needs to be stepped multiple
5912 times before it's been fully executing. E.g., architectures
5913 with a delay slot. It needs to be stepped twice, once for
5914 the instruction and once for the delay slot. */
5915 int step_through_delay
5916 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5918 if (debug_infrun
&& step_through_delay
)
5919 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5920 if (ecs
->event_thread
->control
.step_range_end
== 0
5921 && step_through_delay
)
5923 /* The user issued a continue when stopped at a breakpoint.
5924 Set up for another trap and get out of here. */
5925 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5929 else if (step_through_delay
)
5931 /* The user issued a step when stopped at a breakpoint.
5932 Maybe we should stop, maybe we should not - the delay
5933 slot *might* correspond to a line of source. In any
5934 case, don't decide that here, just set
5935 ecs->stepping_over_breakpoint, making sure we
5936 single-step again before breakpoints are re-inserted. */
5937 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5941 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5942 handles this event. */
5943 ecs
->event_thread
->control
.stop_bpstat
5944 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5945 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5947 /* Following in case break condition called a
5949 stop_print_frame
= 1;
5951 /* This is where we handle "moribund" watchpoints. Unlike
5952 software breakpoints traps, hardware watchpoint traps are
5953 always distinguishable from random traps. If no high-level
5954 watchpoint is associated with the reported stop data address
5955 anymore, then the bpstat does not explain the signal ---
5956 simply make sure to ignore it if `stopped_by_watchpoint' is
5960 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5961 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5963 && stopped_by_watchpoint
)
5964 fprintf_unfiltered (gdb_stdlog
,
5965 "infrun: no user watchpoint explains "
5966 "watchpoint SIGTRAP, ignoring\n");
5968 /* NOTE: cagney/2003-03-29: These checks for a random signal
5969 at one stage in the past included checks for an inferior
5970 function call's call dummy's return breakpoint. The original
5971 comment, that went with the test, read:
5973 ``End of a stack dummy. Some systems (e.g. Sony news) give
5974 another signal besides SIGTRAP, so check here as well as
5977 If someone ever tries to get call dummys on a
5978 non-executable stack to work (where the target would stop
5979 with something like a SIGSEGV), then those tests might need
5980 to be re-instated. Given, however, that the tests were only
5981 enabled when momentary breakpoints were not being used, I
5982 suspect that it won't be the case.
5984 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5985 be necessary for call dummies on a non-executable stack on
5988 /* See if the breakpoints module can explain the signal. */
5990 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5991 ecs
->event_thread
->suspend
.stop_signal
);
5993 /* Maybe this was a trap for a software breakpoint that has since
5995 if (random_signal
&& target_stopped_by_sw_breakpoint ())
5997 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
5999 struct regcache
*regcache
;
6002 /* Re-adjust PC to what the program would see if GDB was not
6004 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
6005 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6008 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
6010 if (record_full_is_used ())
6011 record_full_gdb_operation_disable_set ();
6013 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
6015 do_cleanups (old_cleanups
);
6020 /* A delayed software breakpoint event. Ignore the trap. */
6022 fprintf_unfiltered (gdb_stdlog
,
6023 "infrun: delayed software breakpoint "
6024 "trap, ignoring\n");
6029 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6030 has since been removed. */
6031 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6033 /* A delayed hardware breakpoint event. Ignore the trap. */
6035 fprintf_unfiltered (gdb_stdlog
,
6036 "infrun: delayed hardware breakpoint/watchpoint "
6037 "trap, ignoring\n");
6041 /* If not, perhaps stepping/nexting can. */
6043 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6044 && currently_stepping (ecs
->event_thread
));
6046 /* Perhaps the thread hit a single-step breakpoint of _another_
6047 thread. Single-step breakpoints are transparent to the
6048 breakpoints module. */
6050 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6052 /* No? Perhaps we got a moribund watchpoint. */
6054 random_signal
= !stopped_by_watchpoint
;
6056 /* For the program's own signals, act according to
6057 the signal handling tables. */
6061 /* Signal not for debugging purposes. */
6062 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
6063 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6066 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
6067 gdb_signal_to_symbol_string (stop_signal
));
6069 stopped_by_random_signal
= 1;
6071 /* Always stop on signals if we're either just gaining control
6072 of the program, or the user explicitly requested this thread
6073 to remain stopped. */
6074 if (stop_soon
!= NO_STOP_QUIETLY
6075 || ecs
->event_thread
->stop_requested
6077 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
6083 /* Notify observers the signal has "handle print" set. Note we
6084 returned early above if stopping; normal_stop handles the
6085 printing in that case. */
6086 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6088 /* The signal table tells us to print about this signal. */
6089 target_terminal_ours_for_output ();
6090 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
6091 target_terminal_inferior ();
6094 /* Clear the signal if it should not be passed. */
6095 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6096 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6098 if (ecs
->event_thread
->prev_pc
== stop_pc
6099 && ecs
->event_thread
->control
.trap_expected
6100 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6104 /* We were just starting a new sequence, attempting to
6105 single-step off of a breakpoint and expecting a SIGTRAP.
6106 Instead this signal arrives. This signal will take us out
6107 of the stepping range so GDB needs to remember to, when
6108 the signal handler returns, resume stepping off that
6110 /* To simplify things, "continue" is forced to use the same
6111 code paths as single-step - set a breakpoint at the
6112 signal return address and then, once hit, step off that
6115 fprintf_unfiltered (gdb_stdlog
,
6116 "infrun: signal arrived while stepping over "
6119 was_in_line
= step_over_info_valid_p ();
6120 clear_step_over_info ();
6121 insert_hp_step_resume_breakpoint_at_frame (frame
);
6122 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6123 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6124 ecs
->event_thread
->control
.trap_expected
= 0;
6126 if (target_is_non_stop_p ())
6128 /* Either "set non-stop" is "on", or the target is
6129 always in non-stop mode. In this case, we have a bit
6130 more work to do. Resume the current thread, and if
6131 we had paused all threads, restart them while the
6132 signal handler runs. */
6137 restart_threads (ecs
->event_thread
);
6139 else if (debug_infrun
)
6141 fprintf_unfiltered (gdb_stdlog
,
6142 "infrun: no need to restart threads\n");
6147 /* If we were nexting/stepping some other thread, switch to
6148 it, so that we don't continue it, losing control. */
6149 if (!switch_back_to_stepped_thread (ecs
))
6154 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6155 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6156 || ecs
->event_thread
->control
.step_range_end
== 1)
6157 && frame_id_eq (get_stack_frame_id (frame
),
6158 ecs
->event_thread
->control
.step_stack_frame_id
)
6159 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6161 /* The inferior is about to take a signal that will take it
6162 out of the single step range. Set a breakpoint at the
6163 current PC (which is presumably where the signal handler
6164 will eventually return) and then allow the inferior to
6167 Note that this is only needed for a signal delivered
6168 while in the single-step range. Nested signals aren't a
6169 problem as they eventually all return. */
6171 fprintf_unfiltered (gdb_stdlog
,
6172 "infrun: signal may take us out of "
6173 "single-step range\n");
6175 clear_step_over_info ();
6176 insert_hp_step_resume_breakpoint_at_frame (frame
);
6177 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6178 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6179 ecs
->event_thread
->control
.trap_expected
= 0;
6184 /* Note: step_resume_breakpoint may be non-NULL. This occures
6185 when either there's a nested signal, or when there's a
6186 pending signal enabled just as the signal handler returns
6187 (leaving the inferior at the step-resume-breakpoint without
6188 actually executing it). Either way continue until the
6189 breakpoint is really hit. */
6191 if (!switch_back_to_stepped_thread (ecs
))
6194 fprintf_unfiltered (gdb_stdlog
,
6195 "infrun: random signal, keep going\n");
6202 process_event_stop_test (ecs
);
6205 /* Come here when we've got some debug event / signal we can explain
6206 (IOW, not a random signal), and test whether it should cause a
6207 stop, or whether we should resume the inferior (transparently).
6208 E.g., could be a breakpoint whose condition evaluates false; we
6209 could be still stepping within the line; etc. */
6212 process_event_stop_test (struct execution_control_state
*ecs
)
6214 struct symtab_and_line stop_pc_sal
;
6215 struct frame_info
*frame
;
6216 struct gdbarch
*gdbarch
;
6217 CORE_ADDR jmp_buf_pc
;
6218 struct bpstat_what what
;
6220 /* Handle cases caused by hitting a breakpoint. */
6222 frame
= get_current_frame ();
6223 gdbarch
= get_frame_arch (frame
);
6225 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6227 if (what
.call_dummy
)
6229 stop_stack_dummy
= what
.call_dummy
;
6232 /* A few breakpoint types have callbacks associated (e.g.,
6233 bp_jit_event). Run them now. */
6234 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6236 /* If we hit an internal event that triggers symbol changes, the
6237 current frame will be invalidated within bpstat_what (e.g., if we
6238 hit an internal solib event). Re-fetch it. */
6239 frame
= get_current_frame ();
6240 gdbarch
= get_frame_arch (frame
);
6242 switch (what
.main_action
)
6244 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6245 /* If we hit the breakpoint at longjmp while stepping, we
6246 install a momentary breakpoint at the target of the
6250 fprintf_unfiltered (gdb_stdlog
,
6251 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6253 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6255 if (what
.is_longjmp
)
6257 struct value
*arg_value
;
6259 /* If we set the longjmp breakpoint via a SystemTap probe,
6260 then use it to extract the arguments. The destination PC
6261 is the third argument to the probe. */
6262 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6265 jmp_buf_pc
= value_as_address (arg_value
);
6266 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6268 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6269 || !gdbarch_get_longjmp_target (gdbarch
,
6270 frame
, &jmp_buf_pc
))
6273 fprintf_unfiltered (gdb_stdlog
,
6274 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6275 "(!gdbarch_get_longjmp_target)\n");
6280 /* Insert a breakpoint at resume address. */
6281 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6284 check_exception_resume (ecs
, frame
);
6288 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6290 struct frame_info
*init_frame
;
6292 /* There are several cases to consider.
6294 1. The initiating frame no longer exists. In this case we
6295 must stop, because the exception or longjmp has gone too
6298 2. The initiating frame exists, and is the same as the
6299 current frame. We stop, because the exception or longjmp
6302 3. The initiating frame exists and is different from the
6303 current frame. This means the exception or longjmp has
6304 been caught beneath the initiating frame, so keep going.
6306 4. longjmp breakpoint has been placed just to protect
6307 against stale dummy frames and user is not interested in
6308 stopping around longjmps. */
6311 fprintf_unfiltered (gdb_stdlog
,
6312 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6314 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6316 delete_exception_resume_breakpoint (ecs
->event_thread
);
6318 if (what
.is_longjmp
)
6320 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6322 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6330 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6334 struct frame_id current_id
6335 = get_frame_id (get_current_frame ());
6336 if (frame_id_eq (current_id
,
6337 ecs
->event_thread
->initiating_frame
))
6339 /* Case 2. Fall through. */
6349 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6351 delete_step_resume_breakpoint (ecs
->event_thread
);
6353 end_stepping_range (ecs
);
6357 case BPSTAT_WHAT_SINGLE
:
6359 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6360 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6361 /* Still need to check other stuff, at least the case where we
6362 are stepping and step out of the right range. */
6365 case BPSTAT_WHAT_STEP_RESUME
:
6367 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6369 delete_step_resume_breakpoint (ecs
->event_thread
);
6370 if (ecs
->event_thread
->control
.proceed_to_finish
6371 && execution_direction
== EXEC_REVERSE
)
6373 struct thread_info
*tp
= ecs
->event_thread
;
6375 /* We are finishing a function in reverse, and just hit the
6376 step-resume breakpoint at the start address of the
6377 function, and we're almost there -- just need to back up
6378 by one more single-step, which should take us back to the
6380 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6384 fill_in_stop_func (gdbarch
, ecs
);
6385 if (stop_pc
== ecs
->stop_func_start
6386 && execution_direction
== EXEC_REVERSE
)
6388 /* We are stepping over a function call in reverse, and just
6389 hit the step-resume breakpoint at the start address of
6390 the function. Go back to single-stepping, which should
6391 take us back to the function call. */
6392 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6398 case BPSTAT_WHAT_STOP_NOISY
:
6400 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6401 stop_print_frame
= 1;
6403 /* Assume the thread stopped for a breapoint. We'll still check
6404 whether a/the breakpoint is there when the thread is next
6406 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6411 case BPSTAT_WHAT_STOP_SILENT
:
6413 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6414 stop_print_frame
= 0;
6416 /* Assume the thread stopped for a breapoint. We'll still check
6417 whether a/the breakpoint is there when the thread is next
6419 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6423 case BPSTAT_WHAT_HP_STEP_RESUME
:
6425 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6427 delete_step_resume_breakpoint (ecs
->event_thread
);
6428 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6430 /* Back when the step-resume breakpoint was inserted, we
6431 were trying to single-step off a breakpoint. Go back to
6433 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6434 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6440 case BPSTAT_WHAT_KEEP_CHECKING
:
6444 /* If we stepped a permanent breakpoint and we had a high priority
6445 step-resume breakpoint for the address we stepped, but we didn't
6446 hit it, then we must have stepped into the signal handler. The
6447 step-resume was only necessary to catch the case of _not_
6448 stepping into the handler, so delete it, and fall through to
6449 checking whether the step finished. */
6450 if (ecs
->event_thread
->stepped_breakpoint
)
6452 struct breakpoint
*sr_bp
6453 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6456 && sr_bp
->loc
->permanent
6457 && sr_bp
->type
== bp_hp_step_resume
6458 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6461 fprintf_unfiltered (gdb_stdlog
,
6462 "infrun: stepped permanent breakpoint, stopped in "
6464 delete_step_resume_breakpoint (ecs
->event_thread
);
6465 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6469 /* We come here if we hit a breakpoint but should not stop for it.
6470 Possibly we also were stepping and should stop for that. So fall
6471 through and test for stepping. But, if not stepping, do not
6474 /* In all-stop mode, if we're currently stepping but have stopped in
6475 some other thread, we need to switch back to the stepped thread. */
6476 if (switch_back_to_stepped_thread (ecs
))
6479 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6482 fprintf_unfiltered (gdb_stdlog
,
6483 "infrun: step-resume breakpoint is inserted\n");
6485 /* Having a step-resume breakpoint overrides anything
6486 else having to do with stepping commands until
6487 that breakpoint is reached. */
6492 if (ecs
->event_thread
->control
.step_range_end
== 0)
6495 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6496 /* Likewise if we aren't even stepping. */
6501 /* Re-fetch current thread's frame in case the code above caused
6502 the frame cache to be re-initialized, making our FRAME variable
6503 a dangling pointer. */
6504 frame
= get_current_frame ();
6505 gdbarch
= get_frame_arch (frame
);
6506 fill_in_stop_func (gdbarch
, ecs
);
6508 /* If stepping through a line, keep going if still within it.
6510 Note that step_range_end is the address of the first instruction
6511 beyond the step range, and NOT the address of the last instruction
6514 Note also that during reverse execution, we may be stepping
6515 through a function epilogue and therefore must detect when
6516 the current-frame changes in the middle of a line. */
6518 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6519 && (execution_direction
!= EXEC_REVERSE
6520 || frame_id_eq (get_frame_id (frame
),
6521 ecs
->event_thread
->control
.step_frame_id
)))
6525 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6526 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6527 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6529 /* Tentatively re-enable range stepping; `resume' disables it if
6530 necessary (e.g., if we're stepping over a breakpoint or we
6531 have software watchpoints). */
6532 ecs
->event_thread
->control
.may_range_step
= 1;
6534 /* When stepping backward, stop at beginning of line range
6535 (unless it's the function entry point, in which case
6536 keep going back to the call point). */
6537 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6538 && stop_pc
!= ecs
->stop_func_start
6539 && execution_direction
== EXEC_REVERSE
)
6540 end_stepping_range (ecs
);
6547 /* We stepped out of the stepping range. */
6549 /* If we are stepping at the source level and entered the runtime
6550 loader dynamic symbol resolution code...
6552 EXEC_FORWARD: we keep on single stepping until we exit the run
6553 time loader code and reach the callee's address.
6555 EXEC_REVERSE: we've already executed the callee (backward), and
6556 the runtime loader code is handled just like any other
6557 undebuggable function call. Now we need only keep stepping
6558 backward through the trampoline code, and that's handled further
6559 down, so there is nothing for us to do here. */
6561 if (execution_direction
!= EXEC_REVERSE
6562 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6563 && in_solib_dynsym_resolve_code (stop_pc
))
6565 CORE_ADDR pc_after_resolver
=
6566 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6569 fprintf_unfiltered (gdb_stdlog
,
6570 "infrun: stepped into dynsym resolve code\n");
6572 if (pc_after_resolver
)
6574 /* Set up a step-resume breakpoint at the address
6575 indicated by SKIP_SOLIB_RESOLVER. */
6576 struct symtab_and_line sr_sal
;
6579 sr_sal
.pc
= pc_after_resolver
;
6580 sr_sal
.pspace
= get_frame_program_space (frame
);
6582 insert_step_resume_breakpoint_at_sal (gdbarch
,
6583 sr_sal
, null_frame_id
);
6590 if (ecs
->event_thread
->control
.step_range_end
!= 1
6591 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6592 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6593 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6596 fprintf_unfiltered (gdb_stdlog
,
6597 "infrun: stepped into signal trampoline\n");
6598 /* The inferior, while doing a "step" or "next", has ended up in
6599 a signal trampoline (either by a signal being delivered or by
6600 the signal handler returning). Just single-step until the
6601 inferior leaves the trampoline (either by calling the handler
6607 /* If we're in the return path from a shared library trampoline,
6608 we want to proceed through the trampoline when stepping. */
6609 /* macro/2012-04-25: This needs to come before the subroutine
6610 call check below as on some targets return trampolines look
6611 like subroutine calls (MIPS16 return thunks). */
6612 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6613 stop_pc
, ecs
->stop_func_name
)
6614 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6616 /* Determine where this trampoline returns. */
6617 CORE_ADDR real_stop_pc
;
6619 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6622 fprintf_unfiltered (gdb_stdlog
,
6623 "infrun: stepped into solib return tramp\n");
6625 /* Only proceed through if we know where it's going. */
6628 /* And put the step-breakpoint there and go until there. */
6629 struct symtab_and_line sr_sal
;
6631 init_sal (&sr_sal
); /* initialize to zeroes */
6632 sr_sal
.pc
= real_stop_pc
;
6633 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6634 sr_sal
.pspace
= get_frame_program_space (frame
);
6636 /* Do not specify what the fp should be when we stop since
6637 on some machines the prologue is where the new fp value
6639 insert_step_resume_breakpoint_at_sal (gdbarch
,
6640 sr_sal
, null_frame_id
);
6642 /* Restart without fiddling with the step ranges or
6649 /* Check for subroutine calls. The check for the current frame
6650 equalling the step ID is not necessary - the check of the
6651 previous frame's ID is sufficient - but it is a common case and
6652 cheaper than checking the previous frame's ID.
6654 NOTE: frame_id_eq will never report two invalid frame IDs as
6655 being equal, so to get into this block, both the current and
6656 previous frame must have valid frame IDs. */
6657 /* The outer_frame_id check is a heuristic to detect stepping
6658 through startup code. If we step over an instruction which
6659 sets the stack pointer from an invalid value to a valid value,
6660 we may detect that as a subroutine call from the mythical
6661 "outermost" function. This could be fixed by marking
6662 outermost frames as !stack_p,code_p,special_p. Then the
6663 initial outermost frame, before sp was valid, would
6664 have code_addr == &_start. See the comment in frame_id_eq
6666 if (!frame_id_eq (get_stack_frame_id (frame
),
6667 ecs
->event_thread
->control
.step_stack_frame_id
)
6668 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6669 ecs
->event_thread
->control
.step_stack_frame_id
)
6670 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6672 || (ecs
->event_thread
->control
.step_start_function
6673 != find_pc_function (stop_pc
)))))
6675 CORE_ADDR real_stop_pc
;
6678 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6680 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6682 /* I presume that step_over_calls is only 0 when we're
6683 supposed to be stepping at the assembly language level
6684 ("stepi"). Just stop. */
6685 /* And this works the same backward as frontward. MVS */
6686 end_stepping_range (ecs
);
6690 /* Reverse stepping through solib trampolines. */
6692 if (execution_direction
== EXEC_REVERSE
6693 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6694 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6695 || (ecs
->stop_func_start
== 0
6696 && in_solib_dynsym_resolve_code (stop_pc
))))
6698 /* Any solib trampoline code can be handled in reverse
6699 by simply continuing to single-step. We have already
6700 executed the solib function (backwards), and a few
6701 steps will take us back through the trampoline to the
6707 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6709 /* We're doing a "next".
6711 Normal (forward) execution: set a breakpoint at the
6712 callee's return address (the address at which the caller
6715 Reverse (backward) execution. set the step-resume
6716 breakpoint at the start of the function that we just
6717 stepped into (backwards), and continue to there. When we
6718 get there, we'll need to single-step back to the caller. */
6720 if (execution_direction
== EXEC_REVERSE
)
6722 /* If we're already at the start of the function, we've either
6723 just stepped backward into a single instruction function,
6724 or stepped back out of a signal handler to the first instruction
6725 of the function. Just keep going, which will single-step back
6727 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6729 struct symtab_and_line sr_sal
;
6731 /* Normal function call return (static or dynamic). */
6733 sr_sal
.pc
= ecs
->stop_func_start
;
6734 sr_sal
.pspace
= get_frame_program_space (frame
);
6735 insert_step_resume_breakpoint_at_sal (gdbarch
,
6736 sr_sal
, null_frame_id
);
6740 insert_step_resume_breakpoint_at_caller (frame
);
6746 /* If we are in a function call trampoline (a stub between the
6747 calling routine and the real function), locate the real
6748 function. That's what tells us (a) whether we want to step
6749 into it at all, and (b) what prologue we want to run to the
6750 end of, if we do step into it. */
6751 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6752 if (real_stop_pc
== 0)
6753 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6754 if (real_stop_pc
!= 0)
6755 ecs
->stop_func_start
= real_stop_pc
;
6757 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6759 struct symtab_and_line sr_sal
;
6762 sr_sal
.pc
= ecs
->stop_func_start
;
6763 sr_sal
.pspace
= get_frame_program_space (frame
);
6765 insert_step_resume_breakpoint_at_sal (gdbarch
,
6766 sr_sal
, null_frame_id
);
6771 /* If we have line number information for the function we are
6772 thinking of stepping into and the function isn't on the skip
6775 If there are several symtabs at that PC (e.g. with include
6776 files), just want to know whether *any* of them have line
6777 numbers. find_pc_line handles this. */
6779 struct symtab_and_line tmp_sal
;
6781 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6782 if (tmp_sal
.line
!= 0
6783 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6786 if (execution_direction
== EXEC_REVERSE
)
6787 handle_step_into_function_backward (gdbarch
, ecs
);
6789 handle_step_into_function (gdbarch
, ecs
);
6794 /* If we have no line number and the step-stop-if-no-debug is
6795 set, we stop the step so that the user has a chance to switch
6796 in assembly mode. */
6797 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6798 && step_stop_if_no_debug
)
6800 end_stepping_range (ecs
);
6804 if (execution_direction
== EXEC_REVERSE
)
6806 /* If we're already at the start of the function, we've either just
6807 stepped backward into a single instruction function without line
6808 number info, or stepped back out of a signal handler to the first
6809 instruction of the function without line number info. Just keep
6810 going, which will single-step back to the caller. */
6811 if (ecs
->stop_func_start
!= stop_pc
)
6813 /* Set a breakpoint at callee's start address.
6814 From there we can step once and be back in the caller. */
6815 struct symtab_and_line sr_sal
;
6818 sr_sal
.pc
= ecs
->stop_func_start
;
6819 sr_sal
.pspace
= get_frame_program_space (frame
);
6820 insert_step_resume_breakpoint_at_sal (gdbarch
,
6821 sr_sal
, null_frame_id
);
6825 /* Set a breakpoint at callee's return address (the address
6826 at which the caller will resume). */
6827 insert_step_resume_breakpoint_at_caller (frame
);
6833 /* Reverse stepping through solib trampolines. */
6835 if (execution_direction
== EXEC_REVERSE
6836 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6838 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6839 || (ecs
->stop_func_start
== 0
6840 && in_solib_dynsym_resolve_code (stop_pc
)))
6842 /* Any solib trampoline code can be handled in reverse
6843 by simply continuing to single-step. We have already
6844 executed the solib function (backwards), and a few
6845 steps will take us back through the trampoline to the
6850 else if (in_solib_dynsym_resolve_code (stop_pc
))
6852 /* Stepped backward into the solib dynsym resolver.
6853 Set a breakpoint at its start and continue, then
6854 one more step will take us out. */
6855 struct symtab_and_line sr_sal
;
6858 sr_sal
.pc
= ecs
->stop_func_start
;
6859 sr_sal
.pspace
= get_frame_program_space (frame
);
6860 insert_step_resume_breakpoint_at_sal (gdbarch
,
6861 sr_sal
, null_frame_id
);
6867 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6869 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6870 the trampoline processing logic, however, there are some trampolines
6871 that have no names, so we should do trampoline handling first. */
6872 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6873 && ecs
->stop_func_name
== NULL
6874 && stop_pc_sal
.line
== 0)
6877 fprintf_unfiltered (gdb_stdlog
,
6878 "infrun: stepped into undebuggable function\n");
6880 /* The inferior just stepped into, or returned to, an
6881 undebuggable function (where there is no debugging information
6882 and no line number corresponding to the address where the
6883 inferior stopped). Since we want to skip this kind of code,
6884 we keep going until the inferior returns from this
6885 function - unless the user has asked us not to (via
6886 set step-mode) or we no longer know how to get back
6887 to the call site. */
6888 if (step_stop_if_no_debug
6889 || !frame_id_p (frame_unwind_caller_id (frame
)))
6891 /* If we have no line number and the step-stop-if-no-debug
6892 is set, we stop the step so that the user has a chance to
6893 switch in assembly mode. */
6894 end_stepping_range (ecs
);
6899 /* Set a breakpoint at callee's return address (the address
6900 at which the caller will resume). */
6901 insert_step_resume_breakpoint_at_caller (frame
);
6907 if (ecs
->event_thread
->control
.step_range_end
== 1)
6909 /* It is stepi or nexti. We always want to stop stepping after
6912 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6913 end_stepping_range (ecs
);
6917 if (stop_pc_sal
.line
== 0)
6919 /* We have no line number information. That means to stop
6920 stepping (does this always happen right after one instruction,
6921 when we do "s" in a function with no line numbers,
6922 or can this happen as a result of a return or longjmp?). */
6924 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6925 end_stepping_range (ecs
);
6929 /* Look for "calls" to inlined functions, part one. If the inline
6930 frame machinery detected some skipped call sites, we have entered
6931 a new inline function. */
6933 if (frame_id_eq (get_frame_id (get_current_frame ()),
6934 ecs
->event_thread
->control
.step_frame_id
)
6935 && inline_skipped_frames (ecs
->ptid
))
6937 struct symtab_and_line call_sal
;
6940 fprintf_unfiltered (gdb_stdlog
,
6941 "infrun: stepped into inlined function\n");
6943 find_frame_sal (get_current_frame (), &call_sal
);
6945 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6947 /* For "step", we're going to stop. But if the call site
6948 for this inlined function is on the same source line as
6949 we were previously stepping, go down into the function
6950 first. Otherwise stop at the call site. */
6952 if (call_sal
.line
== ecs
->event_thread
->current_line
6953 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6954 step_into_inline_frame (ecs
->ptid
);
6956 end_stepping_range (ecs
);
6961 /* For "next", we should stop at the call site if it is on a
6962 different source line. Otherwise continue through the
6963 inlined function. */
6964 if (call_sal
.line
== ecs
->event_thread
->current_line
6965 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6968 end_stepping_range (ecs
);
6973 /* Look for "calls" to inlined functions, part two. If we are still
6974 in the same real function we were stepping through, but we have
6975 to go further up to find the exact frame ID, we are stepping
6976 through a more inlined call beyond its call site. */
6978 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6979 && !frame_id_eq (get_frame_id (get_current_frame ()),
6980 ecs
->event_thread
->control
.step_frame_id
)
6981 && stepped_in_from (get_current_frame (),
6982 ecs
->event_thread
->control
.step_frame_id
))
6985 fprintf_unfiltered (gdb_stdlog
,
6986 "infrun: stepping through inlined function\n");
6988 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6991 end_stepping_range (ecs
);
6995 if ((stop_pc
== stop_pc_sal
.pc
)
6996 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6997 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6999 /* We are at the start of a different line. So stop. Note that
7000 we don't stop if we step into the middle of a different line.
7001 That is said to make things like for (;;) statements work
7004 fprintf_unfiltered (gdb_stdlog
,
7005 "infrun: stepped to a different line\n");
7006 end_stepping_range (ecs
);
7010 /* We aren't done stepping.
7012 Optimize by setting the stepping range to the line.
7013 (We might not be in the original line, but if we entered a
7014 new line in mid-statement, we continue stepping. This makes
7015 things like for(;;) statements work better.) */
7017 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7018 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7019 ecs
->event_thread
->control
.may_range_step
= 1;
7020 set_step_info (frame
, stop_pc_sal
);
7023 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
7027 /* In all-stop mode, if we're currently stepping but have stopped in
7028 some other thread, we may need to switch back to the stepped
7029 thread. Returns true we set the inferior running, false if we left
7030 it stopped (and the event needs further processing). */
7033 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7035 if (!target_is_non_stop_p ())
7037 struct thread_info
*tp
;
7038 struct thread_info
*stepping_thread
;
7040 /* If any thread is blocked on some internal breakpoint, and we
7041 simply need to step over that breakpoint to get it going
7042 again, do that first. */
7044 /* However, if we see an event for the stepping thread, then we
7045 know all other threads have been moved past their breakpoints
7046 already. Let the caller check whether the step is finished,
7047 etc., before deciding to move it past a breakpoint. */
7048 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7051 /* Check if the current thread is blocked on an incomplete
7052 step-over, interrupted by a random signal. */
7053 if (ecs
->event_thread
->control
.trap_expected
7054 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7058 fprintf_unfiltered (gdb_stdlog
,
7059 "infrun: need to finish step-over of [%s]\n",
7060 target_pid_to_str (ecs
->event_thread
->ptid
));
7066 /* Check if the current thread is blocked by a single-step
7067 breakpoint of another thread. */
7068 if (ecs
->hit_singlestep_breakpoint
)
7072 fprintf_unfiltered (gdb_stdlog
,
7073 "infrun: need to step [%s] over single-step "
7075 target_pid_to_str (ecs
->ptid
));
7081 /* If this thread needs yet another step-over (e.g., stepping
7082 through a delay slot), do it first before moving on to
7084 if (thread_still_needs_step_over (ecs
->event_thread
))
7088 fprintf_unfiltered (gdb_stdlog
,
7089 "infrun: thread [%s] still needs step-over\n",
7090 target_pid_to_str (ecs
->event_thread
->ptid
));
7096 /* If scheduler locking applies even if not stepping, there's no
7097 need to walk over threads. Above we've checked whether the
7098 current thread is stepping. If some other thread not the
7099 event thread is stepping, then it must be that scheduler
7100 locking is not in effect. */
7101 if (schedlock_applies (ecs
->event_thread
))
7104 /* Otherwise, we no longer expect a trap in the current thread.
7105 Clear the trap_expected flag before switching back -- this is
7106 what keep_going does as well, if we call it. */
7107 ecs
->event_thread
->control
.trap_expected
= 0;
7109 /* Likewise, clear the signal if it should not be passed. */
7110 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7111 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7113 /* Do all pending step-overs before actually proceeding with
7115 if (start_step_over ())
7117 prepare_to_wait (ecs
);
7121 /* Look for the stepping/nexting thread. */
7122 stepping_thread
= NULL
;
7124 ALL_NON_EXITED_THREADS (tp
)
7126 /* Ignore threads of processes the caller is not
7129 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
7132 /* When stepping over a breakpoint, we lock all threads
7133 except the one that needs to move past the breakpoint.
7134 If a non-event thread has this set, the "incomplete
7135 step-over" check above should have caught it earlier. */
7136 if (tp
->control
.trap_expected
)
7138 internal_error (__FILE__
, __LINE__
,
7139 "[%s] has inconsistent state: "
7140 "trap_expected=%d\n",
7141 target_pid_to_str (tp
->ptid
),
7142 tp
->control
.trap_expected
);
7145 /* Did we find the stepping thread? */
7146 if (tp
->control
.step_range_end
)
7148 /* Yep. There should only one though. */
7149 gdb_assert (stepping_thread
== NULL
);
7151 /* The event thread is handled at the top, before we
7153 gdb_assert (tp
!= ecs
->event_thread
);
7155 /* If some thread other than the event thread is
7156 stepping, then scheduler locking can't be in effect,
7157 otherwise we wouldn't have resumed the current event
7158 thread in the first place. */
7159 gdb_assert (!schedlock_applies (tp
));
7161 stepping_thread
= tp
;
7165 if (stepping_thread
!= NULL
)
7168 fprintf_unfiltered (gdb_stdlog
,
7169 "infrun: switching back to stepped thread\n");
7171 if (keep_going_stepped_thread (stepping_thread
))
7173 prepare_to_wait (ecs
);
7182 /* Set a previously stepped thread back to stepping. Returns true on
7183 success, false if the resume is not possible (e.g., the thread
7187 keep_going_stepped_thread (struct thread_info
*tp
)
7189 struct frame_info
*frame
;
7190 struct execution_control_state ecss
;
7191 struct execution_control_state
*ecs
= &ecss
;
7193 /* If the stepping thread exited, then don't try to switch back and
7194 resume it, which could fail in several different ways depending
7195 on the target. Instead, just keep going.
7197 We can find a stepping dead thread in the thread list in two
7200 - The target supports thread exit events, and when the target
7201 tries to delete the thread from the thread list, inferior_ptid
7202 pointed at the exiting thread. In such case, calling
7203 delete_thread does not really remove the thread from the list;
7204 instead, the thread is left listed, with 'exited' state.
7206 - The target's debug interface does not support thread exit
7207 events, and so we have no idea whatsoever if the previously
7208 stepping thread is still alive. For that reason, we need to
7209 synchronously query the target now. */
7211 if (is_exited (tp
->ptid
)
7212 || !target_thread_alive (tp
->ptid
))
7215 fprintf_unfiltered (gdb_stdlog
,
7216 "infrun: not resuming previously "
7217 "stepped thread, it has vanished\n");
7219 delete_thread (tp
->ptid
);
7224 fprintf_unfiltered (gdb_stdlog
,
7225 "infrun: resuming previously stepped thread\n");
7227 reset_ecs (ecs
, tp
);
7228 switch_to_thread (tp
->ptid
);
7230 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7231 frame
= get_current_frame ();
7233 /* If the PC of the thread we were trying to single-step has
7234 changed, then that thread has trapped or been signaled, but the
7235 event has not been reported to GDB yet. Re-poll the target
7236 looking for this particular thread's event (i.e. temporarily
7237 enable schedlock) by:
7239 - setting a break at the current PC
7240 - resuming that particular thread, only (by setting trap
7243 This prevents us continuously moving the single-step breakpoint
7244 forward, one instruction at a time, overstepping. */
7246 if (stop_pc
!= tp
->prev_pc
)
7251 fprintf_unfiltered (gdb_stdlog
,
7252 "infrun: expected thread advanced also (%s -> %s)\n",
7253 paddress (target_gdbarch (), tp
->prev_pc
),
7254 paddress (target_gdbarch (), stop_pc
));
7256 /* Clear the info of the previous step-over, as it's no longer
7257 valid (if the thread was trying to step over a breakpoint, it
7258 has already succeeded). It's what keep_going would do too,
7259 if we called it. Do this before trying to insert the sss
7260 breakpoint, otherwise if we were previously trying to step
7261 over this exact address in another thread, the breakpoint is
7263 clear_step_over_info ();
7264 tp
->control
.trap_expected
= 0;
7266 insert_single_step_breakpoint (get_frame_arch (frame
),
7267 get_frame_address_space (frame
),
7271 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7272 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7277 fprintf_unfiltered (gdb_stdlog
,
7278 "infrun: expected thread still hasn't advanced\n");
7280 keep_going_pass_signal (ecs
);
7285 /* Is thread TP in the middle of (software or hardware)
7286 single-stepping? (Note the result of this function must never be
7287 passed directly as target_resume's STEP parameter.) */
7290 currently_stepping (struct thread_info
*tp
)
7292 return ((tp
->control
.step_range_end
7293 && tp
->control
.step_resume_breakpoint
== NULL
)
7294 || tp
->control
.trap_expected
7295 || tp
->stepped_breakpoint
7296 || bpstat_should_step ());
7299 /* Inferior has stepped into a subroutine call with source code that
7300 we should not step over. Do step to the first line of code in
7304 handle_step_into_function (struct gdbarch
*gdbarch
,
7305 struct execution_control_state
*ecs
)
7307 struct compunit_symtab
*cust
;
7308 struct symtab_and_line stop_func_sal
, sr_sal
;
7310 fill_in_stop_func (gdbarch
, ecs
);
7312 cust
= find_pc_compunit_symtab (stop_pc
);
7313 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7314 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7315 ecs
->stop_func_start
);
7317 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7318 /* Use the step_resume_break to step until the end of the prologue,
7319 even if that involves jumps (as it seems to on the vax under
7321 /* If the prologue ends in the middle of a source line, continue to
7322 the end of that source line (if it is still within the function).
7323 Otherwise, just go to end of prologue. */
7324 if (stop_func_sal
.end
7325 && stop_func_sal
.pc
!= ecs
->stop_func_start
7326 && stop_func_sal
.end
< ecs
->stop_func_end
)
7327 ecs
->stop_func_start
= stop_func_sal
.end
;
7329 /* Architectures which require breakpoint adjustment might not be able
7330 to place a breakpoint at the computed address. If so, the test
7331 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7332 ecs->stop_func_start to an address at which a breakpoint may be
7333 legitimately placed.
7335 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7336 made, GDB will enter an infinite loop when stepping through
7337 optimized code consisting of VLIW instructions which contain
7338 subinstructions corresponding to different source lines. On
7339 FR-V, it's not permitted to place a breakpoint on any but the
7340 first subinstruction of a VLIW instruction. When a breakpoint is
7341 set, GDB will adjust the breakpoint address to the beginning of
7342 the VLIW instruction. Thus, we need to make the corresponding
7343 adjustment here when computing the stop address. */
7345 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7347 ecs
->stop_func_start
7348 = gdbarch_adjust_breakpoint_address (gdbarch
,
7349 ecs
->stop_func_start
);
7352 if (ecs
->stop_func_start
== stop_pc
)
7354 /* We are already there: stop now. */
7355 end_stepping_range (ecs
);
7360 /* Put the step-breakpoint there and go until there. */
7361 init_sal (&sr_sal
); /* initialize to zeroes */
7362 sr_sal
.pc
= ecs
->stop_func_start
;
7363 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7364 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7366 /* Do not specify what the fp should be when we stop since on
7367 some machines the prologue is where the new fp value is
7369 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7371 /* And make sure stepping stops right away then. */
7372 ecs
->event_thread
->control
.step_range_end
7373 = ecs
->event_thread
->control
.step_range_start
;
7378 /* Inferior has stepped backward into a subroutine call with source
7379 code that we should not step over. Do step to the beginning of the
7380 last line of code in it. */
7383 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7384 struct execution_control_state
*ecs
)
7386 struct compunit_symtab
*cust
;
7387 struct symtab_and_line stop_func_sal
;
7389 fill_in_stop_func (gdbarch
, ecs
);
7391 cust
= find_pc_compunit_symtab (stop_pc
);
7392 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7393 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7394 ecs
->stop_func_start
);
7396 stop_func_sal
= find_pc_line (stop_pc
, 0);
7398 /* OK, we're just going to keep stepping here. */
7399 if (stop_func_sal
.pc
== stop_pc
)
7401 /* We're there already. Just stop stepping now. */
7402 end_stepping_range (ecs
);
7406 /* Else just reset the step range and keep going.
7407 No step-resume breakpoint, they don't work for
7408 epilogues, which can have multiple entry paths. */
7409 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7410 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7416 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7417 This is used to both functions and to skip over code. */
7420 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7421 struct symtab_and_line sr_sal
,
7422 struct frame_id sr_id
,
7423 enum bptype sr_type
)
7425 /* There should never be more than one step-resume or longjmp-resume
7426 breakpoint per thread, so we should never be setting a new
7427 step_resume_breakpoint when one is already active. */
7428 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7429 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7432 fprintf_unfiltered (gdb_stdlog
,
7433 "infrun: inserting step-resume breakpoint at %s\n",
7434 paddress (gdbarch
, sr_sal
.pc
));
7436 inferior_thread ()->control
.step_resume_breakpoint
7437 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7441 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7442 struct symtab_and_line sr_sal
,
7443 struct frame_id sr_id
)
7445 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7450 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7451 This is used to skip a potential signal handler.
7453 This is called with the interrupted function's frame. The signal
7454 handler, when it returns, will resume the interrupted function at
7458 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7460 struct symtab_and_line sr_sal
;
7461 struct gdbarch
*gdbarch
;
7463 gdb_assert (return_frame
!= NULL
);
7464 init_sal (&sr_sal
); /* initialize to zeros */
7466 gdbarch
= get_frame_arch (return_frame
);
7467 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7468 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7469 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7471 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7472 get_stack_frame_id (return_frame
),
7476 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7477 is used to skip a function after stepping into it (for "next" or if
7478 the called function has no debugging information).
7480 The current function has almost always been reached by single
7481 stepping a call or return instruction. NEXT_FRAME belongs to the
7482 current function, and the breakpoint will be set at the caller's
7485 This is a separate function rather than reusing
7486 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7487 get_prev_frame, which may stop prematurely (see the implementation
7488 of frame_unwind_caller_id for an example). */
7491 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7493 struct symtab_and_line sr_sal
;
7494 struct gdbarch
*gdbarch
;
7496 /* We shouldn't have gotten here if we don't know where the call site
7498 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7500 init_sal (&sr_sal
); /* initialize to zeros */
7502 gdbarch
= frame_unwind_caller_arch (next_frame
);
7503 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7504 frame_unwind_caller_pc (next_frame
));
7505 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7506 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7508 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7509 frame_unwind_caller_id (next_frame
));
7512 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7513 new breakpoint at the target of a jmp_buf. The handling of
7514 longjmp-resume uses the same mechanisms used for handling
7515 "step-resume" breakpoints. */
7518 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7520 /* There should never be more than one longjmp-resume breakpoint per
7521 thread, so we should never be setting a new
7522 longjmp_resume_breakpoint when one is already active. */
7523 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7526 fprintf_unfiltered (gdb_stdlog
,
7527 "infrun: inserting longjmp-resume breakpoint at %s\n",
7528 paddress (gdbarch
, pc
));
7530 inferior_thread ()->control
.exception_resume_breakpoint
=
7531 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7534 /* Insert an exception resume breakpoint. TP is the thread throwing
7535 the exception. The block B is the block of the unwinder debug hook
7536 function. FRAME is the frame corresponding to the call to this
7537 function. SYM is the symbol of the function argument holding the
7538 target PC of the exception. */
7541 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7542 const struct block
*b
,
7543 struct frame_info
*frame
,
7548 struct block_symbol vsym
;
7549 struct value
*value
;
7551 struct breakpoint
*bp
;
7553 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
7554 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7555 /* If the value was optimized out, revert to the old behavior. */
7556 if (! value_optimized_out (value
))
7558 handler
= value_as_address (value
);
7561 fprintf_unfiltered (gdb_stdlog
,
7562 "infrun: exception resume at %lx\n",
7563 (unsigned long) handler
);
7565 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7566 handler
, bp_exception_resume
);
7568 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7571 bp
->thread
= tp
->global_num
;
7572 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7575 CATCH (e
, RETURN_MASK_ERROR
)
7577 /* We want to ignore errors here. */
7582 /* A helper for check_exception_resume that sets an
7583 exception-breakpoint based on a SystemTap probe. */
7586 insert_exception_resume_from_probe (struct thread_info
*tp
,
7587 const struct bound_probe
*probe
,
7588 struct frame_info
*frame
)
7590 struct value
*arg_value
;
7592 struct breakpoint
*bp
;
7594 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7598 handler
= value_as_address (arg_value
);
7601 fprintf_unfiltered (gdb_stdlog
,
7602 "infrun: exception resume at %s\n",
7603 paddress (get_objfile_arch (probe
->objfile
),
7606 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7607 handler
, bp_exception_resume
);
7608 bp
->thread
= tp
->global_num
;
7609 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7612 /* This is called when an exception has been intercepted. Check to
7613 see whether the exception's destination is of interest, and if so,
7614 set an exception resume breakpoint there. */
7617 check_exception_resume (struct execution_control_state
*ecs
,
7618 struct frame_info
*frame
)
7620 struct bound_probe probe
;
7621 struct symbol
*func
;
7623 /* First see if this exception unwinding breakpoint was set via a
7624 SystemTap probe point. If so, the probe has two arguments: the
7625 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7626 set a breakpoint there. */
7627 probe
= find_probe_by_pc (get_frame_pc (frame
));
7630 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7634 func
= get_frame_function (frame
);
7640 const struct block
*b
;
7641 struct block_iterator iter
;
7645 /* The exception breakpoint is a thread-specific breakpoint on
7646 the unwinder's debug hook, declared as:
7648 void _Unwind_DebugHook (void *cfa, void *handler);
7650 The CFA argument indicates the frame to which control is
7651 about to be transferred. HANDLER is the destination PC.
7653 We ignore the CFA and set a temporary breakpoint at HANDLER.
7654 This is not extremely efficient but it avoids issues in gdb
7655 with computing the DWARF CFA, and it also works even in weird
7656 cases such as throwing an exception from inside a signal
7659 b
= SYMBOL_BLOCK_VALUE (func
);
7660 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7662 if (!SYMBOL_IS_ARGUMENT (sym
))
7669 insert_exception_resume_breakpoint (ecs
->event_thread
,
7675 CATCH (e
, RETURN_MASK_ERROR
)
7682 stop_waiting (struct execution_control_state
*ecs
)
7685 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7687 clear_step_over_info ();
7689 /* Let callers know we don't want to wait for the inferior anymore. */
7690 ecs
->wait_some_more
= 0;
7692 /* If all-stop, but the target is always in non-stop mode, stop all
7693 threads now that we're presenting the stop to the user. */
7694 if (!non_stop
&& target_is_non_stop_p ())
7695 stop_all_threads ();
7698 /* Like keep_going, but passes the signal to the inferior, even if the
7699 signal is set to nopass. */
7702 keep_going_pass_signal (struct execution_control_state
*ecs
)
7704 /* Make sure normal_stop is called if we get a QUIT handled before
7706 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
7708 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7709 gdb_assert (!ecs
->event_thread
->resumed
);
7711 /* Save the pc before execution, to compare with pc after stop. */
7712 ecs
->event_thread
->prev_pc
7713 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7715 if (ecs
->event_thread
->control
.trap_expected
)
7717 struct thread_info
*tp
= ecs
->event_thread
;
7720 fprintf_unfiltered (gdb_stdlog
,
7721 "infrun: %s has trap_expected set, "
7722 "resuming to collect trap\n",
7723 target_pid_to_str (tp
->ptid
));
7725 /* We haven't yet gotten our trap, and either: intercepted a
7726 non-signal event (e.g., a fork); or took a signal which we
7727 are supposed to pass through to the inferior. Simply
7729 discard_cleanups (old_cleanups
);
7730 resume (ecs
->event_thread
->suspend
.stop_signal
);
7732 else if (step_over_info_valid_p ())
7734 /* Another thread is stepping over a breakpoint in-line. If
7735 this thread needs a step-over too, queue the request. In
7736 either case, this resume must be deferred for later. */
7737 struct thread_info
*tp
= ecs
->event_thread
;
7739 if (ecs
->hit_singlestep_breakpoint
7740 || thread_still_needs_step_over (tp
))
7743 fprintf_unfiltered (gdb_stdlog
,
7744 "infrun: step-over already in progress: "
7745 "step-over for %s deferred\n",
7746 target_pid_to_str (tp
->ptid
));
7747 thread_step_over_chain_enqueue (tp
);
7752 fprintf_unfiltered (gdb_stdlog
,
7753 "infrun: step-over in progress: "
7754 "resume of %s deferred\n",
7755 target_pid_to_str (tp
->ptid
));
7758 discard_cleanups (old_cleanups
);
7762 struct regcache
*regcache
= get_current_regcache ();
7765 step_over_what step_what
;
7767 /* Either the trap was not expected, but we are continuing
7768 anyway (if we got a signal, the user asked it be passed to
7771 We got our expected trap, but decided we should resume from
7774 We're going to run this baby now!
7776 Note that insert_breakpoints won't try to re-insert
7777 already inserted breakpoints. Therefore, we don't
7778 care if breakpoints were already inserted, or not. */
7780 /* If we need to step over a breakpoint, and we're not using
7781 displaced stepping to do so, insert all breakpoints
7782 (watchpoints, etc.) but the one we're stepping over, step one
7783 instruction, and then re-insert the breakpoint when that step
7786 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7788 remove_bp
= (ecs
->hit_singlestep_breakpoint
7789 || (step_what
& STEP_OVER_BREAKPOINT
));
7790 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7792 /* We can't use displaced stepping if we need to step past a
7793 watchpoint. The instruction copied to the scratch pad would
7794 still trigger the watchpoint. */
7796 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7798 set_step_over_info (get_regcache_aspace (regcache
),
7799 regcache_read_pc (regcache
), remove_wps
,
7800 ecs
->event_thread
->global_num
);
7802 else if (remove_wps
)
7803 set_step_over_info (NULL
, 0, remove_wps
, -1);
7805 /* If we now need to do an in-line step-over, we need to stop
7806 all other threads. Note this must be done before
7807 insert_breakpoints below, because that removes the breakpoint
7808 we're about to step over, otherwise other threads could miss
7810 if (step_over_info_valid_p () && target_is_non_stop_p ())
7811 stop_all_threads ();
7813 /* Stop stepping if inserting breakpoints fails. */
7816 insert_breakpoints ();
7818 CATCH (e
, RETURN_MASK_ERROR
)
7820 exception_print (gdb_stderr
, e
);
7822 discard_cleanups (old_cleanups
);
7827 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7829 discard_cleanups (old_cleanups
);
7830 resume (ecs
->event_thread
->suspend
.stop_signal
);
7833 prepare_to_wait (ecs
);
7836 /* Called when we should continue running the inferior, because the
7837 current event doesn't cause a user visible stop. This does the
7838 resuming part; waiting for the next event is done elsewhere. */
7841 keep_going (struct execution_control_state
*ecs
)
7843 if (ecs
->event_thread
->control
.trap_expected
7844 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7845 ecs
->event_thread
->control
.trap_expected
= 0;
7847 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7848 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7849 keep_going_pass_signal (ecs
);
7852 /* This function normally comes after a resume, before
7853 handle_inferior_event exits. It takes care of any last bits of
7854 housekeeping, and sets the all-important wait_some_more flag. */
7857 prepare_to_wait (struct execution_control_state
*ecs
)
7860 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7862 ecs
->wait_some_more
= 1;
7864 if (!target_is_async_p ())
7865 mark_infrun_async_event_handler ();
7868 /* We are done with the step range of a step/next/si/ni command.
7869 Called once for each n of a "step n" operation. */
7872 end_stepping_range (struct execution_control_state
*ecs
)
7874 ecs
->event_thread
->control
.stop_step
= 1;
7878 /* Several print_*_reason functions to print why the inferior has stopped.
7879 We always print something when the inferior exits, or receives a signal.
7880 The rest of the cases are dealt with later on in normal_stop and
7881 print_it_typical. Ideally there should be a call to one of these
7882 print_*_reason functions functions from handle_inferior_event each time
7883 stop_waiting is called.
7885 Note that we don't call these directly, instead we delegate that to
7886 the interpreters, through observers. Interpreters then call these
7887 with whatever uiout is right. */
7890 print_end_stepping_range_reason (struct ui_out
*uiout
)
7892 /* For CLI-like interpreters, print nothing. */
7894 if (ui_out_is_mi_like_p (uiout
))
7896 ui_out_field_string (uiout
, "reason",
7897 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7902 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7904 annotate_signalled ();
7905 if (ui_out_is_mi_like_p (uiout
))
7907 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7908 ui_out_text (uiout
, "\nProgram terminated with signal ");
7909 annotate_signal_name ();
7910 ui_out_field_string (uiout
, "signal-name",
7911 gdb_signal_to_name (siggnal
));
7912 annotate_signal_name_end ();
7913 ui_out_text (uiout
, ", ");
7914 annotate_signal_string ();
7915 ui_out_field_string (uiout
, "signal-meaning",
7916 gdb_signal_to_string (siggnal
));
7917 annotate_signal_string_end ();
7918 ui_out_text (uiout
, ".\n");
7919 ui_out_text (uiout
, "The program no longer exists.\n");
7923 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7925 struct inferior
*inf
= current_inferior ();
7926 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7928 annotate_exited (exitstatus
);
7931 if (ui_out_is_mi_like_p (uiout
))
7932 ui_out_field_string (uiout
, "reason",
7933 async_reason_lookup (EXEC_ASYNC_EXITED
));
7934 ui_out_text (uiout
, "[Inferior ");
7935 ui_out_text (uiout
, plongest (inf
->num
));
7936 ui_out_text (uiout
, " (");
7937 ui_out_text (uiout
, pidstr
);
7938 ui_out_text (uiout
, ") exited with code ");
7939 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
7940 ui_out_text (uiout
, "]\n");
7944 if (ui_out_is_mi_like_p (uiout
))
7946 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7947 ui_out_text (uiout
, "[Inferior ");
7948 ui_out_text (uiout
, plongest (inf
->num
));
7949 ui_out_text (uiout
, " (");
7950 ui_out_text (uiout
, pidstr
);
7951 ui_out_text (uiout
, ") exited normally]\n");
7955 /* Some targets/architectures can do extra processing/display of
7956 segmentation faults. E.g., Intel MPX boundary faults.
7957 Call the architecture dependent function to handle the fault. */
7960 handle_segmentation_fault (struct ui_out
*uiout
)
7962 struct regcache
*regcache
= get_current_regcache ();
7963 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7965 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7966 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7970 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7972 struct thread_info
*thr
= inferior_thread ();
7976 if (ui_out_is_mi_like_p (uiout
))
7978 else if (show_thread_that_caused_stop ())
7982 ui_out_text (uiout
, "\nThread ");
7983 ui_out_field_fmt (uiout
, "thread-id", "%s", print_thread_id (thr
));
7985 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7988 ui_out_text (uiout
, " \"");
7989 ui_out_field_fmt (uiout
, "name", "%s", name
);
7990 ui_out_text (uiout
, "\"");
7994 ui_out_text (uiout
, "\nProgram");
7996 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
7997 ui_out_text (uiout
, " stopped");
8000 ui_out_text (uiout
, " received signal ");
8001 annotate_signal_name ();
8002 if (ui_out_is_mi_like_p (uiout
))
8004 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
8005 ui_out_field_string (uiout
, "signal-name",
8006 gdb_signal_to_name (siggnal
));
8007 annotate_signal_name_end ();
8008 ui_out_text (uiout
, ", ");
8009 annotate_signal_string ();
8010 ui_out_field_string (uiout
, "signal-meaning",
8011 gdb_signal_to_string (siggnal
));
8013 if (siggnal
== GDB_SIGNAL_SEGV
)
8014 handle_segmentation_fault (uiout
);
8016 annotate_signal_string_end ();
8018 ui_out_text (uiout
, ".\n");
8022 print_no_history_reason (struct ui_out
*uiout
)
8024 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
8027 /* Print current location without a level number, if we have changed
8028 functions or hit a breakpoint. Print source line if we have one.
8029 bpstat_print contains the logic deciding in detail what to print,
8030 based on the event(s) that just occurred. */
8033 print_stop_location (struct target_waitstatus
*ws
)
8036 enum print_what source_flag
;
8037 int do_frame_printing
= 1;
8038 struct thread_info
*tp
= inferior_thread ();
8040 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8044 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8045 should) carry around the function and does (or should) use
8046 that when doing a frame comparison. */
8047 if (tp
->control
.stop_step
8048 && frame_id_eq (tp
->control
.step_frame_id
,
8049 get_frame_id (get_current_frame ()))
8050 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
8052 /* Finished step, just print source line. */
8053 source_flag
= SRC_LINE
;
8057 /* Print location and source line. */
8058 source_flag
= SRC_AND_LOC
;
8061 case PRINT_SRC_AND_LOC
:
8062 /* Print location and source line. */
8063 source_flag
= SRC_AND_LOC
;
8065 case PRINT_SRC_ONLY
:
8066 source_flag
= SRC_LINE
;
8069 /* Something bogus. */
8070 source_flag
= SRC_LINE
;
8071 do_frame_printing
= 0;
8074 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8077 /* The behavior of this routine with respect to the source
8079 SRC_LINE: Print only source line
8080 LOCATION: Print only location
8081 SRC_AND_LOC: Print location and source line. */
8082 if (do_frame_printing
)
8083 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8089 print_stop_event (struct ui_out
*uiout
)
8091 struct cleanup
*old_chain
;
8092 struct target_waitstatus last
;
8094 struct thread_info
*tp
;
8096 get_last_target_status (&last_ptid
, &last
);
8098 old_chain
= make_cleanup_restore_current_uiout ();
8099 current_uiout
= uiout
;
8101 print_stop_location (&last
);
8103 /* Display the auto-display expressions. */
8106 do_cleanups (old_chain
);
8108 tp
= inferior_thread ();
8109 if (tp
->thread_fsm
!= NULL
8110 && thread_fsm_finished_p (tp
->thread_fsm
))
8112 struct return_value_info
*rv
;
8114 rv
= thread_fsm_return_value (tp
->thread_fsm
);
8116 print_return_value (uiout
, rv
);
8123 maybe_remove_breakpoints (void)
8125 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
8127 if (remove_breakpoints ())
8129 target_terminal_ours_for_output ();
8130 printf_filtered (_("Cannot remove breakpoints because "
8131 "program is no longer writable.\nFurther "
8132 "execution is probably impossible.\n"));
8137 /* The execution context that just caused a normal stop. */
8144 /* The event PTID. */
8148 /* If stopp for a thread event, this is the thread that caused the
8150 struct thread_info
*thread
;
8152 /* The inferior that caused the stop. */
8156 /* Returns a new stop context. If stopped for a thread event, this
8157 takes a strong reference to the thread. */
8159 static struct stop_context
*
8160 save_stop_context (void)
8162 struct stop_context
*sc
= XNEW (struct stop_context
);
8164 sc
->stop_id
= get_stop_id ();
8165 sc
->ptid
= inferior_ptid
;
8166 sc
->inf_num
= current_inferior ()->num
;
8168 if (!ptid_equal (inferior_ptid
, null_ptid
))
8170 /* Take a strong reference so that the thread can't be deleted
8172 sc
->thread
= inferior_thread ();
8173 sc
->thread
->refcount
++;
8181 /* Release a stop context previously created with save_stop_context.
8182 Releases the strong reference to the thread as well. */
8185 release_stop_context_cleanup (void *arg
)
8187 struct stop_context
*sc
= (struct stop_context
*) arg
;
8189 if (sc
->thread
!= NULL
)
8190 sc
->thread
->refcount
--;
8194 /* Return true if the current context no longer matches the saved stop
8198 stop_context_changed (struct stop_context
*prev
)
8200 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
8202 if (prev
->inf_num
!= current_inferior ()->num
)
8204 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
8206 if (get_stop_id () != prev
->stop_id
)
8216 struct target_waitstatus last
;
8218 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
8220 struct switch_thru_all_uis state
;
8222 get_last_target_status (&last_ptid
, &last
);
8226 /* If an exception is thrown from this point on, make sure to
8227 propagate GDB's knowledge of the executing state to the
8228 frontend/user running state. A QUIT is an easy exception to see
8229 here, so do this before any filtered output. */
8231 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
8232 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8233 || last
.kind
== TARGET_WAITKIND_EXITED
)
8235 /* On some targets, we may still have live threads in the
8236 inferior when we get a process exit event. E.g., for
8237 "checkpoint", when the current checkpoint/fork exits,
8238 linux-fork.c automatically switches to another fork from
8239 within target_mourn_inferior. */
8240 if (!ptid_equal (inferior_ptid
, null_ptid
))
8242 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8243 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8246 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8247 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8249 /* As we're presenting a stop, and potentially removing breakpoints,
8250 update the thread list so we can tell whether there are threads
8251 running on the target. With target remote, for example, we can
8252 only learn about new threads when we explicitly update the thread
8253 list. Do this before notifying the interpreters about signal
8254 stops, end of stepping ranges, etc., so that the "new thread"
8255 output is emitted before e.g., "Program received signal FOO",
8256 instead of after. */
8257 update_thread_list ();
8259 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8260 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
8262 /* As with the notification of thread events, we want to delay
8263 notifying the user that we've switched thread context until
8264 the inferior actually stops.
8266 There's no point in saying anything if the inferior has exited.
8267 Note that SIGNALLED here means "exited with a signal", not
8268 "received a signal".
8270 Also skip saying anything in non-stop mode. In that mode, as we
8271 don't want GDB to switch threads behind the user's back, to avoid
8272 races where the user is typing a command to apply to thread x,
8273 but GDB switches to thread y before the user finishes entering
8274 the command, fetch_inferior_event installs a cleanup to restore
8275 the current thread back to the thread the user had selected right
8276 after this event is handled, so we're not really switching, only
8277 informing of a stop. */
8279 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8280 && target_has_execution
8281 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8282 && last
.kind
!= TARGET_WAITKIND_EXITED
8283 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8285 SWITCH_THRU_ALL_UIS (state
)
8287 target_terminal_ours_for_output ();
8288 printf_filtered (_("[Switching to %s]\n"),
8289 target_pid_to_str (inferior_ptid
));
8290 annotate_thread_changed ();
8292 previous_inferior_ptid
= inferior_ptid
;
8295 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8297 SWITCH_THRU_ALL_UIS (state
)
8298 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8300 target_terminal_ours_for_output ();
8301 printf_filtered (_("No unwaited-for children left.\n"));
8305 /* Note: this depends on the update_thread_list call above. */
8306 maybe_remove_breakpoints ();
8308 /* If an auto-display called a function and that got a signal,
8309 delete that auto-display to avoid an infinite recursion. */
8311 if (stopped_by_random_signal
)
8312 disable_current_display ();
8314 SWITCH_THRU_ALL_UIS (state
)
8316 async_enable_stdin ();
8319 /* Let the user/frontend see the threads as stopped. */
8320 do_cleanups (old_chain
);
8322 /* Select innermost stack frame - i.e., current frame is frame 0,
8323 and current location is based on that. Handle the case where the
8324 dummy call is returning after being stopped. E.g. the dummy call
8325 previously hit a breakpoint. (If the dummy call returns
8326 normally, we won't reach here.) Do this before the stop hook is
8327 run, so that it doesn't get to see the temporary dummy frame,
8328 which is not where we'll present the stop. */
8329 if (has_stack_frames ())
8331 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8333 /* Pop the empty frame that contains the stack dummy. This
8334 also restores inferior state prior to the call (struct
8335 infcall_suspend_state). */
8336 struct frame_info
*frame
= get_current_frame ();
8338 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8340 /* frame_pop calls reinit_frame_cache as the last thing it
8341 does which means there's now no selected frame. */
8344 select_frame (get_current_frame ());
8346 /* Set the current source location. */
8347 set_current_sal_from_frame (get_current_frame ());
8350 /* Look up the hook_stop and run it (CLI internally handles problem
8351 of stop_command's pre-hook not existing). */
8352 if (stop_command
!= NULL
)
8354 struct stop_context
*saved_context
= save_stop_context ();
8355 struct cleanup
*old_chain
8356 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8358 catch_errors (hook_stop_stub
, stop_command
,
8359 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
8361 /* If the stop hook resumes the target, then there's no point in
8362 trying to notify about the previous stop; its context is
8363 gone. Likewise if the command switches thread or inferior --
8364 the observers would print a stop for the wrong
8366 if (stop_context_changed (saved_context
))
8368 do_cleanups (old_chain
);
8371 do_cleanups (old_chain
);
8374 /* Notify observers about the stop. This is where the interpreters
8375 print the stop event. */
8376 if (!ptid_equal (inferior_ptid
, null_ptid
))
8377 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
8380 observer_notify_normal_stop (NULL
, stop_print_frame
);
8382 annotate_stopped ();
8384 if (target_has_execution
)
8386 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8387 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8388 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8389 Delete any breakpoint that is to be deleted at the next stop. */
8390 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8393 /* Try to get rid of automatically added inferiors that are no
8394 longer needed. Keeping those around slows down things linearly.
8395 Note that this never removes the current inferior. */
8402 hook_stop_stub (void *cmd
)
8404 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
8409 signal_stop_state (int signo
)
8411 return signal_stop
[signo
];
8415 signal_print_state (int signo
)
8417 return signal_print
[signo
];
8421 signal_pass_state (int signo
)
8423 return signal_program
[signo
];
8427 signal_cache_update (int signo
)
8431 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8432 signal_cache_update (signo
);
8437 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8438 && signal_print
[signo
] == 0
8439 && signal_program
[signo
] == 1
8440 && signal_catch
[signo
] == 0);
8444 signal_stop_update (int signo
, int state
)
8446 int ret
= signal_stop
[signo
];
8448 signal_stop
[signo
] = state
;
8449 signal_cache_update (signo
);
8454 signal_print_update (int signo
, int state
)
8456 int ret
= signal_print
[signo
];
8458 signal_print
[signo
] = state
;
8459 signal_cache_update (signo
);
8464 signal_pass_update (int signo
, int state
)
8466 int ret
= signal_program
[signo
];
8468 signal_program
[signo
] = state
;
8469 signal_cache_update (signo
);
8473 /* Update the global 'signal_catch' from INFO and notify the
8477 signal_catch_update (const unsigned int *info
)
8481 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8482 signal_catch
[i
] = info
[i
] > 0;
8483 signal_cache_update (-1);
8484 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8488 sig_print_header (void)
8490 printf_filtered (_("Signal Stop\tPrint\tPass "
8491 "to program\tDescription\n"));
8495 sig_print_info (enum gdb_signal oursig
)
8497 const char *name
= gdb_signal_to_name (oursig
);
8498 int name_padding
= 13 - strlen (name
);
8500 if (name_padding
<= 0)
8503 printf_filtered ("%s", name
);
8504 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8505 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8506 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8507 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8508 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8511 /* Specify how various signals in the inferior should be handled. */
8514 handle_command (char *args
, int from_tty
)
8517 int digits
, wordlen
;
8518 int sigfirst
, signum
, siglast
;
8519 enum gdb_signal oursig
;
8522 unsigned char *sigs
;
8523 struct cleanup
*old_chain
;
8527 error_no_arg (_("signal to handle"));
8530 /* Allocate and zero an array of flags for which signals to handle. */
8532 nsigs
= (int) GDB_SIGNAL_LAST
;
8533 sigs
= (unsigned char *) alloca (nsigs
);
8534 memset (sigs
, 0, nsigs
);
8536 /* Break the command line up into args. */
8538 argv
= gdb_buildargv (args
);
8539 old_chain
= make_cleanup_freeargv (argv
);
8541 /* Walk through the args, looking for signal oursigs, signal names, and
8542 actions. Signal numbers and signal names may be interspersed with
8543 actions, with the actions being performed for all signals cumulatively
8544 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8546 while (*argv
!= NULL
)
8548 wordlen
= strlen (*argv
);
8549 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
8553 sigfirst
= siglast
= -1;
8555 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
8557 /* Apply action to all signals except those used by the
8558 debugger. Silently skip those. */
8561 siglast
= nsigs
- 1;
8563 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
8565 SET_SIGS (nsigs
, sigs
, signal_stop
);
8566 SET_SIGS (nsigs
, sigs
, signal_print
);
8568 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
8570 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8572 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
8574 SET_SIGS (nsigs
, sigs
, signal_print
);
8576 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
8578 SET_SIGS (nsigs
, sigs
, signal_program
);
8580 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
8582 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8584 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
8586 SET_SIGS (nsigs
, sigs
, signal_program
);
8588 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
8590 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8591 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8593 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
8595 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8597 else if (digits
> 0)
8599 /* It is numeric. The numeric signal refers to our own
8600 internal signal numbering from target.h, not to host/target
8601 signal number. This is a feature; users really should be
8602 using symbolic names anyway, and the common ones like
8603 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8605 sigfirst
= siglast
= (int)
8606 gdb_signal_from_command (atoi (*argv
));
8607 if ((*argv
)[digits
] == '-')
8610 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
8612 if (sigfirst
> siglast
)
8614 /* Bet he didn't figure we'd think of this case... */
8622 oursig
= gdb_signal_from_name (*argv
);
8623 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8625 sigfirst
= siglast
= (int) oursig
;
8629 /* Not a number and not a recognized flag word => complain. */
8630 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
8634 /* If any signal numbers or symbol names were found, set flags for
8635 which signals to apply actions to. */
8637 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8639 switch ((enum gdb_signal
) signum
)
8641 case GDB_SIGNAL_TRAP
:
8642 case GDB_SIGNAL_INT
:
8643 if (!allsigs
&& !sigs
[signum
])
8645 if (query (_("%s is used by the debugger.\n\
8646 Are you sure you want to change it? "),
8647 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8653 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8654 gdb_flush (gdb_stdout
);
8659 case GDB_SIGNAL_DEFAULT
:
8660 case GDB_SIGNAL_UNKNOWN
:
8661 /* Make sure that "all" doesn't print these. */
8672 for (signum
= 0; signum
< nsigs
; signum
++)
8675 signal_cache_update (-1);
8676 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8677 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8681 /* Show the results. */
8682 sig_print_header ();
8683 for (; signum
< nsigs
; signum
++)
8685 sig_print_info ((enum gdb_signal
) signum
);
8691 do_cleanups (old_chain
);
8694 /* Complete the "handle" command. */
8696 static VEC (char_ptr
) *
8697 handle_completer (struct cmd_list_element
*ignore
,
8698 const char *text
, const char *word
)
8700 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
8701 static const char * const keywords
[] =
8715 vec_signals
= signal_completer (ignore
, text
, word
);
8716 vec_keywords
= complete_on_enum (keywords
, word
, word
);
8718 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
8719 VEC_free (char_ptr
, vec_signals
);
8720 VEC_free (char_ptr
, vec_keywords
);
8725 gdb_signal_from_command (int num
)
8727 if (num
>= 1 && num
<= 15)
8728 return (enum gdb_signal
) num
;
8729 error (_("Only signals 1-15 are valid as numeric signals.\n\
8730 Use \"info signals\" for a list of symbolic signals."));
8733 /* Print current contents of the tables set by the handle command.
8734 It is possible we should just be printing signals actually used
8735 by the current target (but for things to work right when switching
8736 targets, all signals should be in the signal tables). */
8739 signals_info (char *signum_exp
, int from_tty
)
8741 enum gdb_signal oursig
;
8743 sig_print_header ();
8747 /* First see if this is a symbol name. */
8748 oursig
= gdb_signal_from_name (signum_exp
);
8749 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8751 /* No, try numeric. */
8753 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8755 sig_print_info (oursig
);
8759 printf_filtered ("\n");
8760 /* These ugly casts brought to you by the native VAX compiler. */
8761 for (oursig
= GDB_SIGNAL_FIRST
;
8762 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8763 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8767 if (oursig
!= GDB_SIGNAL_UNKNOWN
8768 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8769 sig_print_info (oursig
);
8772 printf_filtered (_("\nUse the \"handle\" command "
8773 "to change these tables.\n"));
8776 /* The $_siginfo convenience variable is a bit special. We don't know
8777 for sure the type of the value until we actually have a chance to
8778 fetch the data. The type can change depending on gdbarch, so it is
8779 also dependent on which thread you have selected.
8781 1. making $_siginfo be an internalvar that creates a new value on
8784 2. making the value of $_siginfo be an lval_computed value. */
8786 /* This function implements the lval_computed support for reading a
8790 siginfo_value_read (struct value
*v
)
8792 LONGEST transferred
;
8794 /* If we can access registers, so can we access $_siginfo. Likewise
8796 validate_registers_access ();
8799 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8801 value_contents_all_raw (v
),
8803 TYPE_LENGTH (value_type (v
)));
8805 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8806 error (_("Unable to read siginfo"));
8809 /* This function implements the lval_computed support for writing a
8813 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8815 LONGEST transferred
;
8817 /* If we can access registers, so can we access $_siginfo. Likewise
8819 validate_registers_access ();
8821 transferred
= target_write (¤t_target
,
8822 TARGET_OBJECT_SIGNAL_INFO
,
8824 value_contents_all_raw (fromval
),
8826 TYPE_LENGTH (value_type (fromval
)));
8828 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8829 error (_("Unable to write siginfo"));
8832 static const struct lval_funcs siginfo_value_funcs
=
8838 /* Return a new value with the correct type for the siginfo object of
8839 the current thread using architecture GDBARCH. Return a void value
8840 if there's no object available. */
8842 static struct value
*
8843 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8846 if (target_has_stack
8847 && !ptid_equal (inferior_ptid
, null_ptid
)
8848 && gdbarch_get_siginfo_type_p (gdbarch
))
8850 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8852 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8855 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8859 /* infcall_suspend_state contains state about the program itself like its
8860 registers and any signal it received when it last stopped.
8861 This state must be restored regardless of how the inferior function call
8862 ends (either successfully, or after it hits a breakpoint or signal)
8863 if the program is to properly continue where it left off. */
8865 struct infcall_suspend_state
8867 struct thread_suspend_state thread_suspend
;
8871 struct regcache
*registers
;
8873 /* Format of SIGINFO_DATA or NULL if it is not present. */
8874 struct gdbarch
*siginfo_gdbarch
;
8876 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8877 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8878 content would be invalid. */
8879 gdb_byte
*siginfo_data
;
8882 struct infcall_suspend_state
*
8883 save_infcall_suspend_state (void)
8885 struct infcall_suspend_state
*inf_state
;
8886 struct thread_info
*tp
= inferior_thread ();
8887 struct regcache
*regcache
= get_current_regcache ();
8888 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8889 gdb_byte
*siginfo_data
= NULL
;
8891 if (gdbarch_get_siginfo_type_p (gdbarch
))
8893 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8894 size_t len
= TYPE_LENGTH (type
);
8895 struct cleanup
*back_to
;
8897 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8898 back_to
= make_cleanup (xfree
, siginfo_data
);
8900 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8901 siginfo_data
, 0, len
) == len
)
8902 discard_cleanups (back_to
);
8905 /* Errors ignored. */
8906 do_cleanups (back_to
);
8907 siginfo_data
= NULL
;
8911 inf_state
= XCNEW (struct infcall_suspend_state
);
8915 inf_state
->siginfo_gdbarch
= gdbarch
;
8916 inf_state
->siginfo_data
= siginfo_data
;
8919 inf_state
->thread_suspend
= tp
->suspend
;
8921 /* run_inferior_call will not use the signal due to its `proceed' call with
8922 GDB_SIGNAL_0 anyway. */
8923 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8925 inf_state
->stop_pc
= stop_pc
;
8927 inf_state
->registers
= regcache_dup (regcache
);
8932 /* Restore inferior session state to INF_STATE. */
8935 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8937 struct thread_info
*tp
= inferior_thread ();
8938 struct regcache
*regcache
= get_current_regcache ();
8939 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8941 tp
->suspend
= inf_state
->thread_suspend
;
8943 stop_pc
= inf_state
->stop_pc
;
8945 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8947 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8949 /* Errors ignored. */
8950 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8951 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8954 /* The inferior can be gone if the user types "print exit(0)"
8955 (and perhaps other times). */
8956 if (target_has_execution
)
8957 /* NB: The register write goes through to the target. */
8958 regcache_cpy (regcache
, inf_state
->registers
);
8960 discard_infcall_suspend_state (inf_state
);
8964 do_restore_infcall_suspend_state_cleanup (void *state
)
8966 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
8970 make_cleanup_restore_infcall_suspend_state
8971 (struct infcall_suspend_state
*inf_state
)
8973 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8977 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8979 regcache_xfree (inf_state
->registers
);
8980 xfree (inf_state
->siginfo_data
);
8985 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8987 return inf_state
->registers
;
8990 /* infcall_control_state contains state regarding gdb's control of the
8991 inferior itself like stepping control. It also contains session state like
8992 the user's currently selected frame. */
8994 struct infcall_control_state
8996 struct thread_control_state thread_control
;
8997 struct inferior_control_state inferior_control
;
9000 enum stop_stack_kind stop_stack_dummy
;
9001 int stopped_by_random_signal
;
9003 /* ID if the selected frame when the inferior function call was made. */
9004 struct frame_id selected_frame_id
;
9007 /* Save all of the information associated with the inferior<==>gdb
9010 struct infcall_control_state
*
9011 save_infcall_control_state (void)
9013 struct infcall_control_state
*inf_status
=
9014 XNEW (struct infcall_control_state
);
9015 struct thread_info
*tp
= inferior_thread ();
9016 struct inferior
*inf
= current_inferior ();
9018 inf_status
->thread_control
= tp
->control
;
9019 inf_status
->inferior_control
= inf
->control
;
9021 tp
->control
.step_resume_breakpoint
= NULL
;
9022 tp
->control
.exception_resume_breakpoint
= NULL
;
9024 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9025 chain. If caller's caller is walking the chain, they'll be happier if we
9026 hand them back the original chain when restore_infcall_control_state is
9028 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9031 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9032 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9034 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
9040 restore_selected_frame (void *args
)
9042 struct frame_id
*fid
= (struct frame_id
*) args
;
9043 struct frame_info
*frame
;
9045 frame
= frame_find_by_id (*fid
);
9047 /* If inf_status->selected_frame_id is NULL, there was no previously
9051 warning (_("Unable to restore previously selected frame."));
9055 select_frame (frame
);
9060 /* Restore inferior session state to INF_STATUS. */
9063 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9065 struct thread_info
*tp
= inferior_thread ();
9066 struct inferior
*inf
= current_inferior ();
9068 if (tp
->control
.step_resume_breakpoint
)
9069 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9071 if (tp
->control
.exception_resume_breakpoint
)
9072 tp
->control
.exception_resume_breakpoint
->disposition
9073 = disp_del_at_next_stop
;
9075 /* Handle the bpstat_copy of the chain. */
9076 bpstat_clear (&tp
->control
.stop_bpstat
);
9078 tp
->control
= inf_status
->thread_control
;
9079 inf
->control
= inf_status
->inferior_control
;
9082 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9083 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9085 if (target_has_stack
)
9087 /* The point of catch_errors is that if the stack is clobbered,
9088 walking the stack might encounter a garbage pointer and
9089 error() trying to dereference it. */
9091 (restore_selected_frame
, &inf_status
->selected_frame_id
,
9092 "Unable to restore previously selected frame:\n",
9093 RETURN_MASK_ERROR
) == 0)
9094 /* Error in restoring the selected frame. Select the innermost
9096 select_frame (get_current_frame ());
9103 do_restore_infcall_control_state_cleanup (void *sts
)
9105 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
9109 make_cleanup_restore_infcall_control_state
9110 (struct infcall_control_state
*inf_status
)
9112 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
9116 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9118 if (inf_status
->thread_control
.step_resume_breakpoint
)
9119 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9120 = disp_del_at_next_stop
;
9122 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9123 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9124 = disp_del_at_next_stop
;
9126 /* See save_infcall_control_state for info on stop_bpstat. */
9127 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9132 /* restore_inferior_ptid() will be used by the cleanup machinery
9133 to restore the inferior_ptid value saved in a call to
9134 save_inferior_ptid(). */
9137 restore_inferior_ptid (void *arg
)
9139 ptid_t
*saved_ptid_ptr
= (ptid_t
*) arg
;
9141 inferior_ptid
= *saved_ptid_ptr
;
9145 /* Save the value of inferior_ptid so that it may be restored by a
9146 later call to do_cleanups(). Returns the struct cleanup pointer
9147 needed for later doing the cleanup. */
9150 save_inferior_ptid (void)
9152 ptid_t
*saved_ptid_ptr
= XNEW (ptid_t
);
9154 *saved_ptid_ptr
= inferior_ptid
;
9155 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
9161 clear_exit_convenience_vars (void)
9163 clear_internalvar (lookup_internalvar ("_exitsignal"));
9164 clear_internalvar (lookup_internalvar ("_exitcode"));
9168 /* User interface for reverse debugging:
9169 Set exec-direction / show exec-direction commands
9170 (returns error unless target implements to_set_exec_direction method). */
9172 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9173 static const char exec_forward
[] = "forward";
9174 static const char exec_reverse
[] = "reverse";
9175 static const char *exec_direction
= exec_forward
;
9176 static const char *const exec_direction_names
[] = {
9183 set_exec_direction_func (char *args
, int from_tty
,
9184 struct cmd_list_element
*cmd
)
9186 if (target_can_execute_reverse
)
9188 if (!strcmp (exec_direction
, exec_forward
))
9189 execution_direction
= EXEC_FORWARD
;
9190 else if (!strcmp (exec_direction
, exec_reverse
))
9191 execution_direction
= EXEC_REVERSE
;
9195 exec_direction
= exec_forward
;
9196 error (_("Target does not support this operation."));
9201 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9202 struct cmd_list_element
*cmd
, const char *value
)
9204 switch (execution_direction
) {
9206 fprintf_filtered (out
, _("Forward.\n"));
9209 fprintf_filtered (out
, _("Reverse.\n"));
9212 internal_error (__FILE__
, __LINE__
,
9213 _("bogus execution_direction value: %d"),
9214 (int) execution_direction
);
9219 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9220 struct cmd_list_element
*c
, const char *value
)
9222 fprintf_filtered (file
, _("Resuming the execution of threads "
9223 "of all processes is %s.\n"), value
);
9226 /* Implementation of `siginfo' variable. */
9228 static const struct internalvar_funcs siginfo_funcs
=
9235 /* Callback for infrun's target events source. This is marked when a
9236 thread has a pending status to process. */
9239 infrun_async_inferior_event_handler (gdb_client_data data
)
9241 inferior_event_handler (INF_REG_EVENT
, NULL
);
9245 _initialize_infrun (void)
9249 struct cmd_list_element
*c
;
9251 /* Register extra event sources in the event loop. */
9252 infrun_async_inferior_event_token
9253 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9255 add_info ("signals", signals_info
, _("\
9256 What debugger does when program gets various signals.\n\
9257 Specify a signal as argument to print info on that signal only."));
9258 add_info_alias ("handle", "signals", 0);
9260 c
= add_com ("handle", class_run
, handle_command
, _("\
9261 Specify how to handle signals.\n\
9262 Usage: handle SIGNAL [ACTIONS]\n\
9263 Args are signals and actions to apply to those signals.\n\
9264 If no actions are specified, the current settings for the specified signals\n\
9265 will be displayed instead.\n\
9267 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9268 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9269 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9270 The special arg \"all\" is recognized to mean all signals except those\n\
9271 used by the debugger, typically SIGTRAP and SIGINT.\n\
9273 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9274 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9275 Stop means reenter debugger if this signal happens (implies print).\n\
9276 Print means print a message if this signal happens.\n\
9277 Pass means let program see this signal; otherwise program doesn't know.\n\
9278 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9279 Pass and Stop may be combined.\n\
9281 Multiple signals may be specified. Signal numbers and signal names\n\
9282 may be interspersed with actions, with the actions being performed for\n\
9283 all signals cumulatively specified."));
9284 set_cmd_completer (c
, handle_completer
);
9287 stop_command
= add_cmd ("stop", class_obscure
,
9288 not_just_help_class_command
, _("\
9289 There is no `stop' command, but you can set a hook on `stop'.\n\
9290 This allows you to set a list of commands to be run each time execution\n\
9291 of the program stops."), &cmdlist
);
9293 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9294 Set inferior debugging."), _("\
9295 Show inferior debugging."), _("\
9296 When non-zero, inferior specific debugging is enabled."),
9299 &setdebuglist
, &showdebuglist
);
9301 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9302 &debug_displaced
, _("\
9303 Set displaced stepping debugging."), _("\
9304 Show displaced stepping debugging."), _("\
9305 When non-zero, displaced stepping specific debugging is enabled."),
9307 show_debug_displaced
,
9308 &setdebuglist
, &showdebuglist
);
9310 add_setshow_boolean_cmd ("non-stop", no_class
,
9312 Set whether gdb controls the inferior in non-stop mode."), _("\
9313 Show whether gdb controls the inferior in non-stop mode."), _("\
9314 When debugging a multi-threaded program and this setting is\n\
9315 off (the default, also called all-stop mode), when one thread stops\n\
9316 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9317 all other threads in the program while you interact with the thread of\n\
9318 interest. When you continue or step a thread, you can allow the other\n\
9319 threads to run, or have them remain stopped, but while you inspect any\n\
9320 thread's state, all threads stop.\n\
9322 In non-stop mode, when one thread stops, other threads can continue\n\
9323 to run freely. You'll be able to step each thread independently,\n\
9324 leave it stopped or free to run as needed."),
9330 numsigs
= (int) GDB_SIGNAL_LAST
;
9331 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9332 signal_print
= XNEWVEC (unsigned char, numsigs
);
9333 signal_program
= XNEWVEC (unsigned char, numsigs
);
9334 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9335 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9336 for (i
= 0; i
< numsigs
; i
++)
9339 signal_print
[i
] = 1;
9340 signal_program
[i
] = 1;
9341 signal_catch
[i
] = 0;
9344 /* Signals caused by debugger's own actions should not be given to
9345 the program afterwards.
9347 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9348 explicitly specifies that it should be delivered to the target
9349 program. Typically, that would occur when a user is debugging a
9350 target monitor on a simulator: the target monitor sets a
9351 breakpoint; the simulator encounters this breakpoint and halts
9352 the simulation handing control to GDB; GDB, noting that the stop
9353 address doesn't map to any known breakpoint, returns control back
9354 to the simulator; the simulator then delivers the hardware
9355 equivalent of a GDB_SIGNAL_TRAP to the program being
9357 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9358 signal_program
[GDB_SIGNAL_INT
] = 0;
9360 /* Signals that are not errors should not normally enter the debugger. */
9361 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9362 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9363 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9364 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9365 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9366 signal_print
[GDB_SIGNAL_PROF
] = 0;
9367 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9368 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9369 signal_stop
[GDB_SIGNAL_IO
] = 0;
9370 signal_print
[GDB_SIGNAL_IO
] = 0;
9371 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9372 signal_print
[GDB_SIGNAL_POLL
] = 0;
9373 signal_stop
[GDB_SIGNAL_URG
] = 0;
9374 signal_print
[GDB_SIGNAL_URG
] = 0;
9375 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9376 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9377 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9378 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9380 /* These signals are used internally by user-level thread
9381 implementations. (See signal(5) on Solaris.) Like the above
9382 signals, a healthy program receives and handles them as part of
9383 its normal operation. */
9384 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9385 signal_print
[GDB_SIGNAL_LWP
] = 0;
9386 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9387 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9388 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9389 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9390 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9391 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9393 /* Update cached state. */
9394 signal_cache_update (-1);
9396 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9397 &stop_on_solib_events
, _("\
9398 Set stopping for shared library events."), _("\
9399 Show stopping for shared library events."), _("\
9400 If nonzero, gdb will give control to the user when the dynamic linker\n\
9401 notifies gdb of shared library events. The most common event of interest\n\
9402 to the user would be loading/unloading of a new library."),
9403 set_stop_on_solib_events
,
9404 show_stop_on_solib_events
,
9405 &setlist
, &showlist
);
9407 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9408 follow_fork_mode_kind_names
,
9409 &follow_fork_mode_string
, _("\
9410 Set debugger response to a program call of fork or vfork."), _("\
9411 Show debugger response to a program call of fork or vfork."), _("\
9412 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9413 parent - the original process is debugged after a fork\n\
9414 child - the new process is debugged after a fork\n\
9415 The unfollowed process will continue to run.\n\
9416 By default, the debugger will follow the parent process."),
9418 show_follow_fork_mode_string
,
9419 &setlist
, &showlist
);
9421 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9422 follow_exec_mode_names
,
9423 &follow_exec_mode_string
, _("\
9424 Set debugger response to a program call of exec."), _("\
9425 Show debugger response to a program call of exec."), _("\
9426 An exec call replaces the program image of a process.\n\
9428 follow-exec-mode can be:\n\
9430 new - the debugger creates a new inferior and rebinds the process\n\
9431 to this new inferior. The program the process was running before\n\
9432 the exec call can be restarted afterwards by restarting the original\n\
9435 same - the debugger keeps the process bound to the same inferior.\n\
9436 The new executable image replaces the previous executable loaded in\n\
9437 the inferior. Restarting the inferior after the exec call restarts\n\
9438 the executable the process was running after the exec call.\n\
9440 By default, the debugger will use the same inferior."),
9442 show_follow_exec_mode_string
,
9443 &setlist
, &showlist
);
9445 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9446 scheduler_enums
, &scheduler_mode
, _("\
9447 Set mode for locking scheduler during execution."), _("\
9448 Show mode for locking scheduler during execution."), _("\
9449 off == no locking (threads may preempt at any time)\n\
9450 on == full locking (no thread except the current thread may run)\n\
9451 This applies to both normal execution and replay mode.\n\
9452 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9453 In this mode, other threads may run during other commands.\n\
9454 This applies to both normal execution and replay mode.\n\
9455 replay == scheduler locked in replay mode and unlocked during normal execution."),
9456 set_schedlock_func
, /* traps on target vector */
9457 show_scheduler_mode
,
9458 &setlist
, &showlist
);
9460 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9461 Set mode for resuming threads of all processes."), _("\
9462 Show mode for resuming threads of all processes."), _("\
9463 When on, execution commands (such as 'continue' or 'next') resume all\n\
9464 threads of all processes. When off (which is the default), execution\n\
9465 commands only resume the threads of the current process. The set of\n\
9466 threads that are resumed is further refined by the scheduler-locking\n\
9467 mode (see help set scheduler-locking)."),
9469 show_schedule_multiple
,
9470 &setlist
, &showlist
);
9472 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9473 Set mode of the step operation."), _("\
9474 Show mode of the step operation."), _("\
9475 When set, doing a step over a function without debug line information\n\
9476 will stop at the first instruction of that function. Otherwise, the\n\
9477 function is skipped and the step command stops at a different source line."),
9479 show_step_stop_if_no_debug
,
9480 &setlist
, &showlist
);
9482 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9483 &can_use_displaced_stepping
, _("\
9484 Set debugger's willingness to use displaced stepping."), _("\
9485 Show debugger's willingness to use displaced stepping."), _("\
9486 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9487 supported by the target architecture. If off, gdb will not use displaced\n\
9488 stepping to step over breakpoints, even if such is supported by the target\n\
9489 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9490 if the target architecture supports it and non-stop mode is active, but will not\n\
9491 use it in all-stop mode (see help set non-stop)."),
9493 show_can_use_displaced_stepping
,
9494 &setlist
, &showlist
);
9496 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9497 &exec_direction
, _("Set direction of execution.\n\
9498 Options are 'forward' or 'reverse'."),
9499 _("Show direction of execution (forward/reverse)."),
9500 _("Tells gdb whether to execute forward or backward."),
9501 set_exec_direction_func
, show_exec_direction_func
,
9502 &setlist
, &showlist
);
9504 /* Set/show detach-on-fork: user-settable mode. */
9506 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9507 Set whether gdb will detach the child of a fork."), _("\
9508 Show whether gdb will detach the child of a fork."), _("\
9509 Tells gdb whether to detach the child of a fork."),
9510 NULL
, NULL
, &setlist
, &showlist
);
9512 /* Set/show disable address space randomization mode. */
9514 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9515 &disable_randomization
, _("\
9516 Set disabling of debuggee's virtual address space randomization."), _("\
9517 Show disabling of debuggee's virtual address space randomization."), _("\
9518 When this mode is on (which is the default), randomization of the virtual\n\
9519 address space is disabled. Standalone programs run with the randomization\n\
9520 enabled by default on some platforms."),
9521 &set_disable_randomization
,
9522 &show_disable_randomization
,
9523 &setlist
, &showlist
);
9525 /* ptid initializations */
9526 inferior_ptid
= null_ptid
;
9527 target_last_wait_ptid
= minus_one_ptid
;
9529 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9530 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9531 observer_attach_thread_exit (infrun_thread_thread_exit
);
9532 observer_attach_inferior_exit (infrun_inferior_exit
);
9534 /* Explicitly create without lookup, since that tries to create a
9535 value with a void typed value, and when we get here, gdbarch
9536 isn't initialized yet. At this point, we're quite sure there
9537 isn't another convenience variable of the same name. */
9538 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9540 add_setshow_boolean_cmd ("observer", no_class
,
9541 &observer_mode_1
, _("\
9542 Set whether gdb controls the inferior in observer mode."), _("\
9543 Show whether gdb controls the inferior in observer mode."), _("\
9544 In observer mode, GDB can get data from the inferior, but not\n\
9545 affect its execution. Registers and memory may not be changed,\n\
9546 breakpoints may not be set, and the program cannot be interrupted\n\