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
);
2370 target_commit_resume ();
2373 /* Resume the inferior, but allow a QUIT. This is useful if the user
2374 wants to interrupt some lengthy single-stepping operation
2375 (for child processes, the SIGINT goes to the inferior, and so
2376 we get a SIGINT random_signal, but for remote debugging and perhaps
2377 other targets, that's not true).
2379 SIG is the signal to give the inferior (zero for none). */
2381 resume (enum gdb_signal sig
)
2383 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2384 struct regcache
*regcache
= get_current_regcache ();
2385 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2386 struct thread_info
*tp
= inferior_thread ();
2387 CORE_ADDR pc
= regcache_read_pc (regcache
);
2388 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2390 /* This represents the user's step vs continue request. When
2391 deciding whether "set scheduler-locking step" applies, it's the
2392 user's intention that counts. */
2393 const int user_step
= tp
->control
.stepping_command
;
2394 /* This represents what we'll actually request the target to do.
2395 This can decay from a step to a continue, if e.g., we need to
2396 implement single-stepping with breakpoints (software
2400 gdb_assert (!thread_is_in_step_over_chain (tp
));
2404 if (tp
->suspend
.waitstatus_pending_p
)
2410 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2411 fprintf_unfiltered (gdb_stdlog
,
2412 "infrun: resume: thread %s has pending wait status %s "
2413 "(currently_stepping=%d).\n",
2414 target_pid_to_str (tp
->ptid
), statstr
,
2415 currently_stepping (tp
));
2421 /* FIXME: What should we do if we are supposed to resume this
2422 thread with a signal? Maybe we should maintain a queue of
2423 pending signals to deliver. */
2424 if (sig
!= GDB_SIGNAL_0
)
2426 warning (_("Couldn't deliver signal %s to %s."),
2427 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2430 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2431 discard_cleanups (old_cleanups
);
2433 if (target_can_async_p ())
2438 tp
->stepped_breakpoint
= 0;
2440 /* Depends on stepped_breakpoint. */
2441 step
= currently_stepping (tp
);
2443 if (current_inferior ()->waiting_for_vfork_done
)
2445 /* Don't try to single-step a vfork parent that is waiting for
2446 the child to get out of the shared memory region (by exec'ing
2447 or exiting). This is particularly important on software
2448 single-step archs, as the child process would trip on the
2449 software single step breakpoint inserted for the parent
2450 process. Since the parent will not actually execute any
2451 instruction until the child is out of the shared region (such
2452 are vfork's semantics), it is safe to simply continue it.
2453 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2454 the parent, and tell it to `keep_going', which automatically
2455 re-sets it stepping. */
2457 fprintf_unfiltered (gdb_stdlog
,
2458 "infrun: resume : clear step\n");
2463 fprintf_unfiltered (gdb_stdlog
,
2464 "infrun: resume (step=%d, signal=%s), "
2465 "trap_expected=%d, current thread [%s] at %s\n",
2466 step
, gdb_signal_to_symbol_string (sig
),
2467 tp
->control
.trap_expected
,
2468 target_pid_to_str (inferior_ptid
),
2469 paddress (gdbarch
, pc
));
2471 /* Normally, by the time we reach `resume', the breakpoints are either
2472 removed or inserted, as appropriate. The exception is if we're sitting
2473 at a permanent breakpoint; we need to step over it, but permanent
2474 breakpoints can't be removed. So we have to test for it here. */
2475 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2477 if (sig
!= GDB_SIGNAL_0
)
2479 /* We have a signal to pass to the inferior. The resume
2480 may, or may not take us to the signal handler. If this
2481 is a step, we'll need to stop in the signal handler, if
2482 there's one, (if the target supports stepping into
2483 handlers), or in the next mainline instruction, if
2484 there's no handler. If this is a continue, we need to be
2485 sure to run the handler with all breakpoints inserted.
2486 In all cases, set a breakpoint at the current address
2487 (where the handler returns to), and once that breakpoint
2488 is hit, resume skipping the permanent breakpoint. If
2489 that breakpoint isn't hit, then we've stepped into the
2490 signal handler (or hit some other event). We'll delete
2491 the step-resume breakpoint then. */
2494 fprintf_unfiltered (gdb_stdlog
,
2495 "infrun: resume: skipping permanent breakpoint, "
2496 "deliver signal first\n");
2498 clear_step_over_info ();
2499 tp
->control
.trap_expected
= 0;
2501 if (tp
->control
.step_resume_breakpoint
== NULL
)
2503 /* Set a "high-priority" step-resume, as we don't want
2504 user breakpoints at PC to trigger (again) when this
2506 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2507 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2509 tp
->step_after_step_resume_breakpoint
= step
;
2512 insert_breakpoints ();
2516 /* There's no signal to pass, we can go ahead and skip the
2517 permanent breakpoint manually. */
2519 fprintf_unfiltered (gdb_stdlog
,
2520 "infrun: resume: skipping permanent breakpoint\n");
2521 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2522 /* Update pc to reflect the new address from which we will
2523 execute instructions. */
2524 pc
= regcache_read_pc (regcache
);
2528 /* We've already advanced the PC, so the stepping part
2529 is done. Now we need to arrange for a trap to be
2530 reported to handle_inferior_event. Set a breakpoint
2531 at the current PC, and run to it. Don't update
2532 prev_pc, because if we end in
2533 switch_back_to_stepped_thread, we want the "expected
2534 thread advanced also" branch to be taken. IOW, we
2535 don't want this thread to step further from PC
2537 gdb_assert (!step_over_info_valid_p ());
2538 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2539 insert_breakpoints ();
2541 resume_ptid
= internal_resume_ptid (user_step
);
2542 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2543 discard_cleanups (old_cleanups
);
2550 /* If we have a breakpoint to step over, make sure to do a single
2551 step only. Same if we have software watchpoints. */
2552 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2553 tp
->control
.may_range_step
= 0;
2555 /* If enabled, step over breakpoints by executing a copy of the
2556 instruction at a different address.
2558 We can't use displaced stepping when we have a signal to deliver;
2559 the comments for displaced_step_prepare explain why. The
2560 comments in the handle_inferior event for dealing with 'random
2561 signals' explain what we do instead.
2563 We can't use displaced stepping when we are waiting for vfork_done
2564 event, displaced stepping breaks the vfork child similarly as single
2565 step software breakpoint. */
2566 if (tp
->control
.trap_expected
2567 && use_displaced_stepping (tp
)
2568 && !step_over_info_valid_p ()
2569 && sig
== GDB_SIGNAL_0
2570 && !current_inferior ()->waiting_for_vfork_done
)
2572 int prepared
= displaced_step_prepare (inferior_ptid
);
2577 fprintf_unfiltered (gdb_stdlog
,
2578 "Got placed in step-over queue\n");
2580 tp
->control
.trap_expected
= 0;
2581 discard_cleanups (old_cleanups
);
2584 else if (prepared
< 0)
2586 /* Fallback to stepping over the breakpoint in-line. */
2588 if (target_is_non_stop_p ())
2589 stop_all_threads ();
2591 set_step_over_info (get_regcache_aspace (regcache
),
2592 regcache_read_pc (regcache
), 0, tp
->global_num
);
2594 step
= maybe_software_singlestep (gdbarch
, pc
);
2596 insert_breakpoints ();
2598 else if (prepared
> 0)
2600 struct displaced_step_inferior_state
*displaced
;
2602 /* Update pc to reflect the new address from which we will
2603 execute instructions due to displaced stepping. */
2604 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2606 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2607 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2608 displaced
->step_closure
);
2612 /* Do we need to do it the hard way, w/temp breakpoints? */
2614 step
= maybe_software_singlestep (gdbarch
, pc
);
2616 /* Currently, our software single-step implementation leads to different
2617 results than hardware single-stepping in one situation: when stepping
2618 into delivering a signal which has an associated signal handler,
2619 hardware single-step will stop at the first instruction of the handler,
2620 while software single-step will simply skip execution of the handler.
2622 For now, this difference in behavior is accepted since there is no
2623 easy way to actually implement single-stepping into a signal handler
2624 without kernel support.
2626 However, there is one scenario where this difference leads to follow-on
2627 problems: if we're stepping off a breakpoint by removing all breakpoints
2628 and then single-stepping. In this case, the software single-step
2629 behavior means that even if there is a *breakpoint* in the signal
2630 handler, GDB still would not stop.
2632 Fortunately, we can at least fix this particular issue. We detect
2633 here the case where we are about to deliver a signal while software
2634 single-stepping with breakpoints removed. In this situation, we
2635 revert the decisions to remove all breakpoints and insert single-
2636 step breakpoints, and instead we install a step-resume breakpoint
2637 at the current address, deliver the signal without stepping, and
2638 once we arrive back at the step-resume breakpoint, actually step
2639 over the breakpoint we originally wanted to step over. */
2640 if (thread_has_single_step_breakpoints_set (tp
)
2641 && sig
!= GDB_SIGNAL_0
2642 && step_over_info_valid_p ())
2644 /* If we have nested signals or a pending signal is delivered
2645 immediately after a handler returns, might might already have
2646 a step-resume breakpoint set on the earlier handler. We cannot
2647 set another step-resume breakpoint; just continue on until the
2648 original breakpoint is hit. */
2649 if (tp
->control
.step_resume_breakpoint
== NULL
)
2651 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2652 tp
->step_after_step_resume_breakpoint
= 1;
2655 delete_single_step_breakpoints (tp
);
2657 clear_step_over_info ();
2658 tp
->control
.trap_expected
= 0;
2660 insert_breakpoints ();
2663 /* If STEP is set, it's a request to use hardware stepping
2664 facilities. But in that case, we should never
2665 use singlestep breakpoint. */
2666 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2668 /* Decide the set of threads to ask the target to resume. */
2669 if (tp
->control
.trap_expected
)
2671 /* We're allowing a thread to run past a breakpoint it has
2672 hit, either by single-stepping the thread with the breakpoint
2673 removed, or by displaced stepping, with the breakpoint inserted.
2674 In the former case, we need to single-step only this thread,
2675 and keep others stopped, as they can miss this breakpoint if
2676 allowed to run. That's not really a problem for displaced
2677 stepping, but, we still keep other threads stopped, in case
2678 another thread is also stopped for a breakpoint waiting for
2679 its turn in the displaced stepping queue. */
2680 resume_ptid
= inferior_ptid
;
2683 resume_ptid
= internal_resume_ptid (user_step
);
2685 if (execution_direction
!= EXEC_REVERSE
2686 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2688 /* There are two cases where we currently need to step a
2689 breakpoint instruction when we have a signal to deliver:
2691 - See handle_signal_stop where we handle random signals that
2692 could take out us out of the stepping range. Normally, in
2693 that case we end up continuing (instead of stepping) over the
2694 signal handler with a breakpoint at PC, but there are cases
2695 where we should _always_ single-step, even if we have a
2696 step-resume breakpoint, like when a software watchpoint is
2697 set. Assuming single-stepping and delivering a signal at the
2698 same time would takes us to the signal handler, then we could
2699 have removed the breakpoint at PC to step over it. However,
2700 some hardware step targets (like e.g., Mac OS) can't step
2701 into signal handlers, and for those, we need to leave the
2702 breakpoint at PC inserted, as otherwise if the handler
2703 recurses and executes PC again, it'll miss the breakpoint.
2704 So we leave the breakpoint inserted anyway, but we need to
2705 record that we tried to step a breakpoint instruction, so
2706 that adjust_pc_after_break doesn't end up confused.
2708 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2709 in one thread after another thread that was stepping had been
2710 momentarily paused for a step-over. When we re-resume the
2711 stepping thread, it may be resumed from that address with a
2712 breakpoint that hasn't trapped yet. Seen with
2713 gdb.threads/non-stop-fair-events.exp, on targets that don't
2714 do displaced stepping. */
2717 fprintf_unfiltered (gdb_stdlog
,
2718 "infrun: resume: [%s] stepped breakpoint\n",
2719 target_pid_to_str (tp
->ptid
));
2721 tp
->stepped_breakpoint
= 1;
2723 /* Most targets can step a breakpoint instruction, thus
2724 executing it normally. But if this one cannot, just
2725 continue and we will hit it anyway. */
2726 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2731 && tp
->control
.trap_expected
2732 && use_displaced_stepping (tp
)
2733 && !step_over_info_valid_p ())
2735 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2736 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2737 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2740 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2741 paddress (resume_gdbarch
, actual_pc
));
2742 read_memory (actual_pc
, buf
, sizeof (buf
));
2743 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2746 if (tp
->control
.may_range_step
)
2748 /* If we're resuming a thread with the PC out of the step
2749 range, then we're doing some nested/finer run control
2750 operation, like stepping the thread out of the dynamic
2751 linker or the displaced stepping scratch pad. We
2752 shouldn't have allowed a range step then. */
2753 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2756 do_target_resume (resume_ptid
, step
, sig
);
2758 discard_cleanups (old_cleanups
);
2765 /* Counter that tracks number of user visible stops. This can be used
2766 to tell whether a command has proceeded the inferior past the
2767 current location. This allows e.g., inferior function calls in
2768 breakpoint commands to not interrupt the command list. When the
2769 call finishes successfully, the inferior is standing at the same
2770 breakpoint as if nothing happened (and so we don't call
2772 static ULONGEST current_stop_id
;
2779 return current_stop_id
;
2782 /* Called when we report a user visible stop. */
2790 /* Clear out all variables saying what to do when inferior is continued.
2791 First do this, then set the ones you want, then call `proceed'. */
2794 clear_proceed_status_thread (struct thread_info
*tp
)
2797 fprintf_unfiltered (gdb_stdlog
,
2798 "infrun: clear_proceed_status_thread (%s)\n",
2799 target_pid_to_str (tp
->ptid
));
2801 /* If we're starting a new sequence, then the previous finished
2802 single-step is no longer relevant. */
2803 if (tp
->suspend
.waitstatus_pending_p
)
2805 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2808 fprintf_unfiltered (gdb_stdlog
,
2809 "infrun: clear_proceed_status: pending "
2810 "event of %s was a finished step. "
2812 target_pid_to_str (tp
->ptid
));
2814 tp
->suspend
.waitstatus_pending_p
= 0;
2815 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2817 else if (debug_infrun
)
2821 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2822 fprintf_unfiltered (gdb_stdlog
,
2823 "infrun: clear_proceed_status_thread: thread %s "
2824 "has pending wait status %s "
2825 "(currently_stepping=%d).\n",
2826 target_pid_to_str (tp
->ptid
), statstr
,
2827 currently_stepping (tp
));
2832 /* If this signal should not be seen by program, give it zero.
2833 Used for debugging signals. */
2834 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2835 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2837 thread_fsm_delete (tp
->thread_fsm
);
2838 tp
->thread_fsm
= NULL
;
2840 tp
->control
.trap_expected
= 0;
2841 tp
->control
.step_range_start
= 0;
2842 tp
->control
.step_range_end
= 0;
2843 tp
->control
.may_range_step
= 0;
2844 tp
->control
.step_frame_id
= null_frame_id
;
2845 tp
->control
.step_stack_frame_id
= null_frame_id
;
2846 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2847 tp
->control
.step_start_function
= NULL
;
2848 tp
->stop_requested
= 0;
2850 tp
->control
.stop_step
= 0;
2852 tp
->control
.proceed_to_finish
= 0;
2854 tp
->control
.stepping_command
= 0;
2856 /* Discard any remaining commands or status from previous stop. */
2857 bpstat_clear (&tp
->control
.stop_bpstat
);
2861 clear_proceed_status (int step
)
2863 /* With scheduler-locking replay, stop replaying other threads if we're
2864 not replaying the user-visible resume ptid.
2866 This is a convenience feature to not require the user to explicitly
2867 stop replaying the other threads. We're assuming that the user's
2868 intent is to resume tracing the recorded process. */
2869 if (!non_stop
&& scheduler_mode
== schedlock_replay
2870 && target_record_is_replaying (minus_one_ptid
)
2871 && !target_record_will_replay (user_visible_resume_ptid (step
),
2872 execution_direction
))
2873 target_record_stop_replaying ();
2877 struct thread_info
*tp
;
2880 resume_ptid
= user_visible_resume_ptid (step
);
2882 /* In all-stop mode, delete the per-thread status of all threads
2883 we're about to resume, implicitly and explicitly. */
2884 ALL_NON_EXITED_THREADS (tp
)
2886 if (!ptid_match (tp
->ptid
, resume_ptid
))
2888 clear_proceed_status_thread (tp
);
2892 if (!ptid_equal (inferior_ptid
, null_ptid
))
2894 struct inferior
*inferior
;
2898 /* If in non-stop mode, only delete the per-thread status of
2899 the current thread. */
2900 clear_proceed_status_thread (inferior_thread ());
2903 inferior
= current_inferior ();
2904 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2907 observer_notify_about_to_proceed ();
2910 /* Returns true if TP is still stopped at a breakpoint that needs
2911 stepping-over in order to make progress. If the breakpoint is gone
2912 meanwhile, we can skip the whole step-over dance. */
2915 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2917 if (tp
->stepping_over_breakpoint
)
2919 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2921 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2922 regcache_read_pc (regcache
))
2923 == ordinary_breakpoint_here
)
2926 tp
->stepping_over_breakpoint
= 0;
2932 /* Check whether thread TP still needs to start a step-over in order
2933 to make progress when resumed. Returns an bitwise or of enum
2934 step_over_what bits, indicating what needs to be stepped over. */
2936 static step_over_what
2937 thread_still_needs_step_over (struct thread_info
*tp
)
2939 step_over_what what
= 0;
2941 if (thread_still_needs_step_over_bp (tp
))
2942 what
|= STEP_OVER_BREAKPOINT
;
2944 if (tp
->stepping_over_watchpoint
2945 && !target_have_steppable_watchpoint
)
2946 what
|= STEP_OVER_WATCHPOINT
;
2951 /* Returns true if scheduler locking applies. STEP indicates whether
2952 we're about to do a step/next-like command to a thread. */
2955 schedlock_applies (struct thread_info
*tp
)
2957 return (scheduler_mode
== schedlock_on
2958 || (scheduler_mode
== schedlock_step
2959 && tp
->control
.stepping_command
)
2960 || (scheduler_mode
== schedlock_replay
2961 && target_record_will_replay (minus_one_ptid
,
2962 execution_direction
)));
2965 /* Basic routine for continuing the program in various fashions.
2967 ADDR is the address to resume at, or -1 for resume where stopped.
2968 SIGGNAL is the signal to give it, or 0 for none,
2969 or -1 for act according to how it stopped.
2970 STEP is nonzero if should trap after one instruction.
2971 -1 means return after that and print nothing.
2972 You should probably set various step_... variables
2973 before calling here, if you are stepping.
2975 You should call clear_proceed_status before calling proceed. */
2978 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2980 struct regcache
*regcache
;
2981 struct gdbarch
*gdbarch
;
2982 struct thread_info
*tp
;
2984 struct address_space
*aspace
;
2986 struct execution_control_state ecss
;
2987 struct execution_control_state
*ecs
= &ecss
;
2988 struct cleanup
*old_chain
;
2989 struct cleanup
*defer_resume_cleanup
;
2992 /* If we're stopped at a fork/vfork, follow the branch set by the
2993 "set follow-fork-mode" command; otherwise, we'll just proceed
2994 resuming the current thread. */
2995 if (!follow_fork ())
2997 /* The target for some reason decided not to resume. */
2999 if (target_can_async_p ())
3000 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3004 /* We'll update this if & when we switch to a new thread. */
3005 previous_inferior_ptid
= inferior_ptid
;
3007 regcache
= get_current_regcache ();
3008 gdbarch
= get_regcache_arch (regcache
);
3009 aspace
= get_regcache_aspace (regcache
);
3010 pc
= regcache_read_pc (regcache
);
3011 tp
= inferior_thread ();
3013 /* Fill in with reasonable starting values. */
3014 init_thread_stepping_state (tp
);
3016 gdb_assert (!thread_is_in_step_over_chain (tp
));
3018 if (addr
== (CORE_ADDR
) -1)
3021 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3022 && execution_direction
!= EXEC_REVERSE
)
3023 /* There is a breakpoint at the address we will resume at,
3024 step one instruction before inserting breakpoints so that
3025 we do not stop right away (and report a second hit at this
3028 Note, we don't do this in reverse, because we won't
3029 actually be executing the breakpoint insn anyway.
3030 We'll be (un-)executing the previous instruction. */
3031 tp
->stepping_over_breakpoint
= 1;
3032 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3033 && gdbarch_single_step_through_delay (gdbarch
,
3034 get_current_frame ()))
3035 /* We stepped onto an instruction that needs to be stepped
3036 again before re-inserting the breakpoint, do so. */
3037 tp
->stepping_over_breakpoint
= 1;
3041 regcache_write_pc (regcache
, addr
);
3044 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3045 tp
->suspend
.stop_signal
= siggnal
;
3047 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3049 /* If an exception is thrown from this point on, make sure to
3050 propagate GDB's knowledge of the executing state to the
3051 frontend/user running state. */
3052 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3054 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3055 threads (e.g., we might need to set threads stepping over
3056 breakpoints first), from the user/frontend's point of view, all
3057 threads in RESUME_PTID are now running. Unless we're calling an
3058 inferior function, as in that case we pretend the inferior
3059 doesn't run at all. */
3060 if (!tp
->control
.in_infcall
)
3061 set_running (resume_ptid
, 1);
3064 fprintf_unfiltered (gdb_stdlog
,
3065 "infrun: proceed (addr=%s, signal=%s)\n",
3066 paddress (gdbarch
, addr
),
3067 gdb_signal_to_symbol_string (siggnal
));
3069 annotate_starting ();
3071 /* Make sure that output from GDB appears before output from the
3073 gdb_flush (gdb_stdout
);
3075 /* In a multi-threaded task we may select another thread and
3076 then continue or step.
3078 But if a thread that we're resuming had stopped at a breakpoint,
3079 it will immediately cause another breakpoint stop without any
3080 execution (i.e. it will report a breakpoint hit incorrectly). So
3081 we must step over it first.
3083 Look for threads other than the current (TP) that reported a
3084 breakpoint hit and haven't been resumed yet since. */
3086 /* If scheduler locking applies, we can avoid iterating over all
3088 if (!non_stop
&& !schedlock_applies (tp
))
3090 struct thread_info
*current
= tp
;
3092 ALL_NON_EXITED_THREADS (tp
)
3094 /* Ignore the current thread here. It's handled
3099 /* Ignore threads of processes we're not resuming. */
3100 if (!ptid_match (tp
->ptid
, resume_ptid
))
3103 if (!thread_still_needs_step_over (tp
))
3106 gdb_assert (!thread_is_in_step_over_chain (tp
));
3109 fprintf_unfiltered (gdb_stdlog
,
3110 "infrun: need to step-over [%s] first\n",
3111 target_pid_to_str (tp
->ptid
));
3113 thread_step_over_chain_enqueue (tp
);
3119 /* Enqueue the current thread last, so that we move all other
3120 threads over their breakpoints first. */
3121 if (tp
->stepping_over_breakpoint
)
3122 thread_step_over_chain_enqueue (tp
);
3124 /* If the thread isn't started, we'll still need to set its prev_pc,
3125 so that switch_back_to_stepped_thread knows the thread hasn't
3126 advanced. Must do this before resuming any thread, as in
3127 all-stop/remote, once we resume we can't send any other packet
3128 until the target stops again. */
3129 tp
->prev_pc
= regcache_read_pc (regcache
);
3131 defer_resume_cleanup
= make_cleanup_defer_target_commit_resume ();
3133 started
= start_step_over ();
3135 if (step_over_info_valid_p ())
3137 /* Either this thread started a new in-line step over, or some
3138 other thread was already doing one. In either case, don't
3139 resume anything else until the step-over is finished. */
3141 else if (started
&& !target_is_non_stop_p ())
3143 /* A new displaced stepping sequence was started. In all-stop,
3144 we can't talk to the target anymore until it next stops. */
3146 else if (!non_stop
&& target_is_non_stop_p ())
3148 /* In all-stop, but the target is always in non-stop mode.
3149 Start all other threads that are implicitly resumed too. */
3150 ALL_NON_EXITED_THREADS (tp
)
3152 /* Ignore threads of processes we're not resuming. */
3153 if (!ptid_match (tp
->ptid
, resume_ptid
))
3159 fprintf_unfiltered (gdb_stdlog
,
3160 "infrun: proceed: [%s] resumed\n",
3161 target_pid_to_str (tp
->ptid
));
3162 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3166 if (thread_is_in_step_over_chain (tp
))
3169 fprintf_unfiltered (gdb_stdlog
,
3170 "infrun: proceed: [%s] needs step-over\n",
3171 target_pid_to_str (tp
->ptid
));
3176 fprintf_unfiltered (gdb_stdlog
,
3177 "infrun: proceed: resuming %s\n",
3178 target_pid_to_str (tp
->ptid
));
3180 reset_ecs (ecs
, tp
);
3181 switch_to_thread (tp
->ptid
);
3182 keep_going_pass_signal (ecs
);
3183 if (!ecs
->wait_some_more
)
3184 error (_("Command aborted."));
3187 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3189 /* The thread wasn't started, and isn't queued, run it now. */
3190 reset_ecs (ecs
, tp
);
3191 switch_to_thread (tp
->ptid
);
3192 keep_going_pass_signal (ecs
);
3193 if (!ecs
->wait_some_more
)
3194 error (_("Command aborted."));
3197 do_cleanups (defer_resume_cleanup
);
3198 target_commit_resume ();
3200 discard_cleanups (old_chain
);
3202 /* Tell the event loop to wait for it to stop. If the target
3203 supports asynchronous execution, it'll do this from within
3205 if (!target_can_async_p ())
3206 mark_async_event_handler (infrun_async_inferior_event_token
);
3210 /* Start remote-debugging of a machine over a serial link. */
3213 start_remote (int from_tty
)
3215 struct inferior
*inferior
;
3217 inferior
= current_inferior ();
3218 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3220 /* Always go on waiting for the target, regardless of the mode. */
3221 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3222 indicate to wait_for_inferior that a target should timeout if
3223 nothing is returned (instead of just blocking). Because of this,
3224 targets expecting an immediate response need to, internally, set
3225 things up so that the target_wait() is forced to eventually
3227 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3228 differentiate to its caller what the state of the target is after
3229 the initial open has been performed. Here we're assuming that
3230 the target has stopped. It should be possible to eventually have
3231 target_open() return to the caller an indication that the target
3232 is currently running and GDB state should be set to the same as
3233 for an async run. */
3234 wait_for_inferior ();
3236 /* Now that the inferior has stopped, do any bookkeeping like
3237 loading shared libraries. We want to do this before normal_stop,
3238 so that the displayed frame is up to date. */
3239 post_create_inferior (¤t_target
, from_tty
);
3244 /* Initialize static vars when a new inferior begins. */
3247 init_wait_for_inferior (void)
3249 /* These are meaningless until the first time through wait_for_inferior. */
3251 breakpoint_init_inferior (inf_starting
);
3253 clear_proceed_status (0);
3255 target_last_wait_ptid
= minus_one_ptid
;
3257 previous_inferior_ptid
= inferior_ptid
;
3259 /* Discard any skipped inlined frames. */
3260 clear_inline_frame_state (minus_one_ptid
);
3265 static void handle_inferior_event (struct execution_control_state
*ecs
);
3267 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3268 struct execution_control_state
*ecs
);
3269 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3270 struct execution_control_state
*ecs
);
3271 static void handle_signal_stop (struct execution_control_state
*ecs
);
3272 static void check_exception_resume (struct execution_control_state
*,
3273 struct frame_info
*);
3275 static void end_stepping_range (struct execution_control_state
*ecs
);
3276 static void stop_waiting (struct execution_control_state
*ecs
);
3277 static void keep_going (struct execution_control_state
*ecs
);
3278 static void process_event_stop_test (struct execution_control_state
*ecs
);
3279 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3281 /* Callback for iterate over threads. If the thread is stopped, but
3282 the user/frontend doesn't know about that yet, go through
3283 normal_stop, as if the thread had just stopped now. ARG points at
3284 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
3285 ptid_is_pid(PTID) is true, applies to all threads of the process
3286 pointed at by PTID. Otherwise, apply only to the thread pointed by
3290 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
3292 ptid_t ptid
= * (ptid_t
*) arg
;
3294 if ((ptid_equal (info
->ptid
, ptid
)
3295 || ptid_equal (minus_one_ptid
, ptid
)
3296 || (ptid_is_pid (ptid
)
3297 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
3298 && is_running (info
->ptid
)
3299 && !is_executing (info
->ptid
))
3301 struct cleanup
*old_chain
;
3302 struct execution_control_state ecss
;
3303 struct execution_control_state
*ecs
= &ecss
;
3305 memset (ecs
, 0, sizeof (*ecs
));
3307 old_chain
= make_cleanup_restore_current_thread ();
3309 overlay_cache_invalid
= 1;
3310 /* Flush target cache before starting to handle each event.
3311 Target was running and cache could be stale. This is just a
3312 heuristic. Running threads may modify target memory, but we
3313 don't get any event. */
3314 target_dcache_invalidate ();
3316 /* Go through handle_inferior_event/normal_stop, so we always
3317 have consistent output as if the stop event had been
3319 ecs
->ptid
= info
->ptid
;
3320 ecs
->event_thread
= info
;
3321 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
3322 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
3324 handle_inferior_event (ecs
);
3326 if (!ecs
->wait_some_more
)
3328 /* Cancel any running execution command. */
3329 thread_cancel_execution_command (info
);
3334 do_cleanups (old_chain
);
3340 /* This function is attached as a "thread_stop_requested" observer.
3341 Cleanup local state that assumed the PTID was to be resumed, and
3342 report the stop to the frontend. */
3345 infrun_thread_stop_requested (ptid_t ptid
)
3347 struct thread_info
*tp
;
3349 /* PTID was requested to stop. Remove matching threads from the
3350 step-over queue, so we don't try to resume them
3352 ALL_NON_EXITED_THREADS (tp
)
3353 if (ptid_match (tp
->ptid
, ptid
))
3355 if (thread_is_in_step_over_chain (tp
))
3356 thread_step_over_chain_remove (tp
);
3359 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
3363 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3365 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3366 nullify_last_target_wait_ptid ();
3369 /* Delete the step resume, single-step and longjmp/exception resume
3370 breakpoints of TP. */
3373 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3375 delete_step_resume_breakpoint (tp
);
3376 delete_exception_resume_breakpoint (tp
);
3377 delete_single_step_breakpoints (tp
);
3380 /* If the target still has execution, call FUNC for each thread that
3381 just stopped. In all-stop, that's all the non-exited threads; in
3382 non-stop, that's the current thread, only. */
3384 typedef void (*for_each_just_stopped_thread_callback_func
)
3385 (struct thread_info
*tp
);
3388 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3390 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3393 if (target_is_non_stop_p ())
3395 /* If in non-stop mode, only the current thread stopped. */
3396 func (inferior_thread ());
3400 struct thread_info
*tp
;
3402 /* In all-stop mode, all threads have stopped. */
3403 ALL_NON_EXITED_THREADS (tp
)
3410 /* Delete the step resume and longjmp/exception resume breakpoints of
3411 the threads that just stopped. */
3414 delete_just_stopped_threads_infrun_breakpoints (void)
3416 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3419 /* Delete the single-step breakpoints of the threads that just
3423 delete_just_stopped_threads_single_step_breakpoints (void)
3425 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3428 /* A cleanup wrapper. */
3431 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3433 delete_just_stopped_threads_infrun_breakpoints ();
3439 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3440 const struct target_waitstatus
*ws
)
3442 char *status_string
= target_waitstatus_to_string (ws
);
3443 struct ui_file
*tmp_stream
= mem_fileopen ();
3446 /* The text is split over several lines because it was getting too long.
3447 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3448 output as a unit; we want only one timestamp printed if debug_timestamp
3451 fprintf_unfiltered (tmp_stream
,
3452 "infrun: target_wait (%d.%ld.%ld",
3453 ptid_get_pid (waiton_ptid
),
3454 ptid_get_lwp (waiton_ptid
),
3455 ptid_get_tid (waiton_ptid
));
3456 if (ptid_get_pid (waiton_ptid
) != -1)
3457 fprintf_unfiltered (tmp_stream
,
3458 " [%s]", target_pid_to_str (waiton_ptid
));
3459 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3460 fprintf_unfiltered (tmp_stream
,
3461 "infrun: %d.%ld.%ld [%s],\n",
3462 ptid_get_pid (result_ptid
),
3463 ptid_get_lwp (result_ptid
),
3464 ptid_get_tid (result_ptid
),
3465 target_pid_to_str (result_ptid
));
3466 fprintf_unfiltered (tmp_stream
,
3470 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3472 /* This uses %s in part to handle %'s in the text, but also to avoid
3473 a gcc error: the format attribute requires a string literal. */
3474 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3476 xfree (status_string
);
3478 ui_file_delete (tmp_stream
);
3481 /* Select a thread at random, out of those which are resumed and have
3484 static struct thread_info
*
3485 random_pending_event_thread (ptid_t waiton_ptid
)
3487 struct thread_info
*event_tp
;
3489 int random_selector
;
3491 /* First see how many events we have. Count only resumed threads
3492 that have an event pending. */
3493 ALL_NON_EXITED_THREADS (event_tp
)
3494 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3495 && event_tp
->resumed
3496 && event_tp
->suspend
.waitstatus_pending_p
)
3499 if (num_events
== 0)
3502 /* Now randomly pick a thread out of those that have had events. */
3503 random_selector
= (int)
3504 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3506 if (debug_infrun
&& num_events
> 1)
3507 fprintf_unfiltered (gdb_stdlog
,
3508 "infrun: Found %d events, selecting #%d\n",
3509 num_events
, random_selector
);
3511 /* Select the Nth thread that has had an event. */
3512 ALL_NON_EXITED_THREADS (event_tp
)
3513 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3514 && event_tp
->resumed
3515 && event_tp
->suspend
.waitstatus_pending_p
)
3516 if (random_selector
-- == 0)
3522 /* Wrapper for target_wait that first checks whether threads have
3523 pending statuses to report before actually asking the target for
3527 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3530 struct thread_info
*tp
;
3532 /* First check if there is a resumed thread with a wait status
3534 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3536 tp
= random_pending_event_thread (ptid
);
3541 fprintf_unfiltered (gdb_stdlog
,
3542 "infrun: Waiting for specific thread %s.\n",
3543 target_pid_to_str (ptid
));
3545 /* We have a specific thread to check. */
3546 tp
= find_thread_ptid (ptid
);
3547 gdb_assert (tp
!= NULL
);
3548 if (!tp
->suspend
.waitstatus_pending_p
)
3553 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3554 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3556 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3557 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3561 pc
= regcache_read_pc (regcache
);
3563 if (pc
!= tp
->suspend
.stop_pc
)
3566 fprintf_unfiltered (gdb_stdlog
,
3567 "infrun: PC of %s changed. was=%s, now=%s\n",
3568 target_pid_to_str (tp
->ptid
),
3569 paddress (gdbarch
, tp
->prev_pc
),
3570 paddress (gdbarch
, pc
));
3573 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3576 fprintf_unfiltered (gdb_stdlog
,
3577 "infrun: previous breakpoint of %s, at %s gone\n",
3578 target_pid_to_str (tp
->ptid
),
3579 paddress (gdbarch
, pc
));
3587 fprintf_unfiltered (gdb_stdlog
,
3588 "infrun: pending event of %s cancelled.\n",
3589 target_pid_to_str (tp
->ptid
));
3591 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3592 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3602 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3603 fprintf_unfiltered (gdb_stdlog
,
3604 "infrun: Using pending wait status %s for %s.\n",
3606 target_pid_to_str (tp
->ptid
));
3610 /* Now that we've selected our final event LWP, un-adjust its PC
3611 if it was a software breakpoint (and the target doesn't
3612 always adjust the PC itself). */
3613 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3614 && !target_supports_stopped_by_sw_breakpoint ())
3616 struct regcache
*regcache
;
3617 struct gdbarch
*gdbarch
;
3620 regcache
= get_thread_regcache (tp
->ptid
);
3621 gdbarch
= get_regcache_arch (regcache
);
3623 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3628 pc
= regcache_read_pc (regcache
);
3629 regcache_write_pc (regcache
, pc
+ decr_pc
);
3633 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3634 *status
= tp
->suspend
.waitstatus
;
3635 tp
->suspend
.waitstatus_pending_p
= 0;
3637 /* Wake up the event loop again, until all pending events are
3639 if (target_is_async_p ())
3640 mark_async_event_handler (infrun_async_inferior_event_token
);
3644 /* But if we don't find one, we'll have to wait. */
3646 if (deprecated_target_wait_hook
)
3647 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3649 event_ptid
= target_wait (ptid
, status
, options
);
3654 /* Prepare and stabilize the inferior for detaching it. E.g.,
3655 detaching while a thread is displaced stepping is a recipe for
3656 crashing it, as nothing would readjust the PC out of the scratch
3660 prepare_for_detach (void)
3662 struct inferior
*inf
= current_inferior ();
3663 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3664 struct cleanup
*old_chain_1
;
3665 struct displaced_step_inferior_state
*displaced
;
3667 displaced
= get_displaced_stepping_state (inf
->pid
);
3669 /* Is any thread of this process displaced stepping? If not,
3670 there's nothing else to do. */
3671 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3675 fprintf_unfiltered (gdb_stdlog
,
3676 "displaced-stepping in-process while detaching");
3678 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3681 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3683 struct cleanup
*old_chain_2
;
3684 struct execution_control_state ecss
;
3685 struct execution_control_state
*ecs
;
3688 memset (ecs
, 0, sizeof (*ecs
));
3690 overlay_cache_invalid
= 1;
3691 /* Flush target cache before starting to handle each event.
3692 Target was running and cache could be stale. This is just a
3693 heuristic. Running threads may modify target memory, but we
3694 don't get any event. */
3695 target_dcache_invalidate ();
3697 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3700 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3702 /* If an error happens while handling the event, propagate GDB's
3703 knowledge of the executing state to the frontend/user running
3705 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3708 /* Now figure out what to do with the result of the result. */
3709 handle_inferior_event (ecs
);
3711 /* No error, don't finish the state yet. */
3712 discard_cleanups (old_chain_2
);
3714 /* Breakpoints and watchpoints are not installed on the target
3715 at this point, and signals are passed directly to the
3716 inferior, so this must mean the process is gone. */
3717 if (!ecs
->wait_some_more
)
3719 discard_cleanups (old_chain_1
);
3720 error (_("Program exited while detaching"));
3724 discard_cleanups (old_chain_1
);
3727 /* Wait for control to return from inferior to debugger.
3729 If inferior gets a signal, we may decide to start it up again
3730 instead of returning. That is why there is a loop in this function.
3731 When this function actually returns it means the inferior
3732 should be left stopped and GDB should read more commands. */
3735 wait_for_inferior (void)
3737 struct cleanup
*old_cleanups
;
3738 struct cleanup
*thread_state_chain
;
3742 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3745 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3748 /* If an error happens while handling the event, propagate GDB's
3749 knowledge of the executing state to the frontend/user running
3751 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3755 struct execution_control_state ecss
;
3756 struct execution_control_state
*ecs
= &ecss
;
3757 ptid_t waiton_ptid
= minus_one_ptid
;
3759 memset (ecs
, 0, sizeof (*ecs
));
3761 overlay_cache_invalid
= 1;
3763 /* Flush target cache before starting to handle each event.
3764 Target was running and cache could be stale. This is just a
3765 heuristic. Running threads may modify target memory, but we
3766 don't get any event. */
3767 target_dcache_invalidate ();
3769 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3772 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3774 /* Now figure out what to do with the result of the result. */
3775 handle_inferior_event (ecs
);
3777 if (!ecs
->wait_some_more
)
3781 /* No error, don't finish the state yet. */
3782 discard_cleanups (thread_state_chain
);
3784 do_cleanups (old_cleanups
);
3787 /* Cleanup that reinstalls the readline callback handler, if the
3788 target is running in the background. If while handling the target
3789 event something triggered a secondary prompt, like e.g., a
3790 pagination prompt, we'll have removed the callback handler (see
3791 gdb_readline_wrapper_line). Need to do this as we go back to the
3792 event loop, ready to process further input. Note this has no
3793 effect if the handler hasn't actually been removed, because calling
3794 rl_callback_handler_install resets the line buffer, thus losing
3798 reinstall_readline_callback_handler_cleanup (void *arg
)
3800 struct ui
*ui
= current_ui
;
3804 /* We're not going back to the top level event loop yet. Don't
3805 install the readline callback, as it'd prep the terminal,
3806 readline-style (raw, noecho) (e.g., --batch). We'll install
3807 it the next time the prompt is displayed, when we're ready
3812 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3813 gdb_rl_callback_handler_reinstall ();
3816 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3817 that's just the event thread. In all-stop, that's all threads. */
3820 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3822 struct thread_info
*thr
= ecs
->event_thread
;
3824 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3825 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3829 ALL_NON_EXITED_THREADS (thr
)
3831 if (thr
->thread_fsm
== NULL
)
3833 if (thr
== ecs
->event_thread
)
3836 switch_to_thread (thr
->ptid
);
3837 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3840 if (ecs
->event_thread
!= NULL
)
3841 switch_to_thread (ecs
->event_thread
->ptid
);
3845 /* Helper for all_uis_check_sync_execution_done that works on the
3849 check_curr_ui_sync_execution_done (void)
3851 struct ui
*ui
= current_ui
;
3853 if (ui
->prompt_state
== PROMPT_NEEDED
3855 && !gdb_in_secondary_prompt_p (ui
))
3857 target_terminal_ours ();
3858 observer_notify_sync_execution_done ();
3859 ui_register_input_event_handler (ui
);
3866 all_uis_check_sync_execution_done (void)
3868 SWITCH_THRU_ALL_UIS ()
3870 check_curr_ui_sync_execution_done ();
3877 all_uis_on_sync_execution_starting (void)
3879 SWITCH_THRU_ALL_UIS ()
3881 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3882 async_disable_stdin ();
3886 /* Asynchronous version of wait_for_inferior. It is called by the
3887 event loop whenever a change of state is detected on the file
3888 descriptor corresponding to the target. It can be called more than
3889 once to complete a single execution command. In such cases we need
3890 to keep the state in a global variable ECSS. If it is the last time
3891 that this function is called for a single execution command, then
3892 report to the user that the inferior has stopped, and do the
3893 necessary cleanups. */
3896 fetch_inferior_event (void *client_data
)
3898 struct execution_control_state ecss
;
3899 struct execution_control_state
*ecs
= &ecss
;
3900 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3901 struct cleanup
*ts_old_chain
;
3903 ptid_t waiton_ptid
= minus_one_ptid
;
3905 memset (ecs
, 0, sizeof (*ecs
));
3907 /* Events are always processed with the main UI as current UI. This
3908 way, warnings, debug output, etc. are always consistently sent to
3909 the main console. */
3910 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3912 /* End up with readline processing input, if necessary. */
3913 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3915 /* We're handling a live event, so make sure we're doing live
3916 debugging. If we're looking at traceframes while the target is
3917 running, we're going to need to get back to that mode after
3918 handling the event. */
3921 make_cleanup_restore_current_traceframe ();
3922 set_current_traceframe (-1);
3926 /* In non-stop mode, the user/frontend should not notice a thread
3927 switch due to internal events. Make sure we reverse to the
3928 user selected thread and frame after handling the event and
3929 running any breakpoint commands. */
3930 make_cleanup_restore_current_thread ();
3932 overlay_cache_invalid
= 1;
3933 /* Flush target cache before starting to handle each event. Target
3934 was running and cache could be stale. This is just a heuristic.
3935 Running threads may modify target memory, but we don't get any
3937 target_dcache_invalidate ();
3939 scoped_restore save_exec_dir
3940 = make_scoped_restore (&execution_direction
, target_execution_direction ());
3942 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3943 target_can_async_p () ? TARGET_WNOHANG
: 0);
3946 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3948 /* If an error happens while handling the event, propagate GDB's
3949 knowledge of the executing state to the frontend/user running
3951 if (!target_is_non_stop_p ())
3952 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3954 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3956 /* Get executed before make_cleanup_restore_current_thread above to apply
3957 still for the thread which has thrown the exception. */
3958 make_bpstat_clear_actions_cleanup ();
3960 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3962 /* Now figure out what to do with the result of the result. */
3963 handle_inferior_event (ecs
);
3965 if (!ecs
->wait_some_more
)
3967 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3968 int should_stop
= 1;
3969 struct thread_info
*thr
= ecs
->event_thread
;
3970 int should_notify_stop
= 1;
3972 delete_just_stopped_threads_infrun_breakpoints ();
3976 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3978 if (thread_fsm
!= NULL
)
3979 should_stop
= thread_fsm_should_stop (thread_fsm
, thr
);
3988 clean_up_just_stopped_threads_fsms (ecs
);
3990 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3993 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
3996 if (should_notify_stop
)
4000 /* We may not find an inferior if this was a process exit. */
4001 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
4002 proceeded
= normal_stop ();
4006 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
4013 /* No error, don't finish the thread states yet. */
4014 discard_cleanups (ts_old_chain
);
4016 /* Revert thread and frame. */
4017 do_cleanups (old_chain
);
4019 /* If a UI was in sync execution mode, and now isn't, restore its
4020 prompt (a synchronous execution command has finished, and we're
4021 ready for input). */
4022 all_uis_check_sync_execution_done ();
4025 && exec_done_display_p
4026 && (ptid_equal (inferior_ptid
, null_ptid
)
4027 || !is_running (inferior_ptid
)))
4028 printf_unfiltered (_("completed.\n"));
4031 /* Record the frame and location we're currently stepping through. */
4033 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
4035 struct thread_info
*tp
= inferior_thread ();
4037 tp
->control
.step_frame_id
= get_frame_id (frame
);
4038 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4040 tp
->current_symtab
= sal
.symtab
;
4041 tp
->current_line
= sal
.line
;
4044 /* Clear context switchable stepping state. */
4047 init_thread_stepping_state (struct thread_info
*tss
)
4049 tss
->stepped_breakpoint
= 0;
4050 tss
->stepping_over_breakpoint
= 0;
4051 tss
->stepping_over_watchpoint
= 0;
4052 tss
->step_after_step_resume_breakpoint
= 0;
4055 /* Set the cached copy of the last ptid/waitstatus. */
4058 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
4060 target_last_wait_ptid
= ptid
;
4061 target_last_waitstatus
= status
;
4064 /* Return the cached copy of the last pid/waitstatus returned by
4065 target_wait()/deprecated_target_wait_hook(). The data is actually
4066 cached by handle_inferior_event(), which gets called immediately
4067 after target_wait()/deprecated_target_wait_hook(). */
4070 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
4072 *ptidp
= target_last_wait_ptid
;
4073 *status
= target_last_waitstatus
;
4077 nullify_last_target_wait_ptid (void)
4079 target_last_wait_ptid
= minus_one_ptid
;
4082 /* Switch thread contexts. */
4085 context_switch (ptid_t ptid
)
4087 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4089 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4090 target_pid_to_str (inferior_ptid
));
4091 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4092 target_pid_to_str (ptid
));
4095 switch_to_thread (ptid
);
4098 /* If the target can't tell whether we've hit breakpoints
4099 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4100 check whether that could have been caused by a breakpoint. If so,
4101 adjust the PC, per gdbarch_decr_pc_after_break. */
4104 adjust_pc_after_break (struct thread_info
*thread
,
4105 struct target_waitstatus
*ws
)
4107 struct regcache
*regcache
;
4108 struct gdbarch
*gdbarch
;
4109 struct address_space
*aspace
;
4110 CORE_ADDR breakpoint_pc
, decr_pc
;
4112 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4113 we aren't, just return.
4115 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4116 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4117 implemented by software breakpoints should be handled through the normal
4120 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4121 different signals (SIGILL or SIGEMT for instance), but it is less
4122 clear where the PC is pointing afterwards. It may not match
4123 gdbarch_decr_pc_after_break. I don't know any specific target that
4124 generates these signals at breakpoints (the code has been in GDB since at
4125 least 1992) so I can not guess how to handle them here.
4127 In earlier versions of GDB, a target with
4128 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4129 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4130 target with both of these set in GDB history, and it seems unlikely to be
4131 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4133 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4136 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4139 /* In reverse execution, when a breakpoint is hit, the instruction
4140 under it has already been de-executed. The reported PC always
4141 points at the breakpoint address, so adjusting it further would
4142 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4145 B1 0x08000000 : INSN1
4146 B2 0x08000001 : INSN2
4148 PC -> 0x08000003 : INSN4
4150 Say you're stopped at 0x08000003 as above. Reverse continuing
4151 from that point should hit B2 as below. Reading the PC when the
4152 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4153 been de-executed already.
4155 B1 0x08000000 : INSN1
4156 B2 PC -> 0x08000001 : INSN2
4160 We can't apply the same logic as for forward execution, because
4161 we would wrongly adjust the PC to 0x08000000, since there's a
4162 breakpoint at PC - 1. We'd then report a hit on B1, although
4163 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4165 if (execution_direction
== EXEC_REVERSE
)
4168 /* If the target can tell whether the thread hit a SW breakpoint,
4169 trust it. Targets that can tell also adjust the PC
4171 if (target_supports_stopped_by_sw_breakpoint ())
4174 /* Note that relying on whether a breakpoint is planted in memory to
4175 determine this can fail. E.g,. the breakpoint could have been
4176 removed since. Or the thread could have been told to step an
4177 instruction the size of a breakpoint instruction, and only
4178 _after_ was a breakpoint inserted at its address. */
4180 /* If this target does not decrement the PC after breakpoints, then
4181 we have nothing to do. */
4182 regcache
= get_thread_regcache (thread
->ptid
);
4183 gdbarch
= get_regcache_arch (regcache
);
4185 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4189 aspace
= get_regcache_aspace (regcache
);
4191 /* Find the location where (if we've hit a breakpoint) the
4192 breakpoint would be. */
4193 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4195 /* If the target can't tell whether a software breakpoint triggered,
4196 fallback to figuring it out based on breakpoints we think were
4197 inserted in the target, and on whether the thread was stepped or
4200 /* Check whether there actually is a software breakpoint inserted at
4203 If in non-stop mode, a race condition is possible where we've
4204 removed a breakpoint, but stop events for that breakpoint were
4205 already queued and arrive later. To suppress those spurious
4206 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4207 and retire them after a number of stop events are reported. Note
4208 this is an heuristic and can thus get confused. The real fix is
4209 to get the "stopped by SW BP and needs adjustment" info out of
4210 the target/kernel (and thus never reach here; see above). */
4211 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4212 || (target_is_non_stop_p ()
4213 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4215 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4217 if (record_full_is_used ())
4218 record_full_gdb_operation_disable_set ();
4220 /* When using hardware single-step, a SIGTRAP is reported for both
4221 a completed single-step and a software breakpoint. Need to
4222 differentiate between the two, as the latter needs adjusting
4223 but the former does not.
4225 The SIGTRAP can be due to a completed hardware single-step only if
4226 - we didn't insert software single-step breakpoints
4227 - this thread is currently being stepped
4229 If any of these events did not occur, we must have stopped due
4230 to hitting a software breakpoint, and have to back up to the
4233 As a special case, we could have hardware single-stepped a
4234 software breakpoint. In this case (prev_pc == breakpoint_pc),
4235 we also need to back up to the breakpoint address. */
4237 if (thread_has_single_step_breakpoints_set (thread
)
4238 || !currently_stepping (thread
)
4239 || (thread
->stepped_breakpoint
4240 && thread
->prev_pc
== breakpoint_pc
))
4241 regcache_write_pc (regcache
, breakpoint_pc
);
4243 do_cleanups (old_cleanups
);
4248 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4250 for (frame
= get_prev_frame (frame
);
4252 frame
= get_prev_frame (frame
))
4254 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4256 if (get_frame_type (frame
) != INLINE_FRAME
)
4263 /* Auxiliary function that handles syscall entry/return events.
4264 It returns 1 if the inferior should keep going (and GDB
4265 should ignore the event), or 0 if the event deserves to be
4269 handle_syscall_event (struct execution_control_state
*ecs
)
4271 struct regcache
*regcache
;
4274 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4275 context_switch (ecs
->ptid
);
4277 regcache
= get_thread_regcache (ecs
->ptid
);
4278 syscall_number
= ecs
->ws
.value
.syscall_number
;
4279 stop_pc
= regcache_read_pc (regcache
);
4281 if (catch_syscall_enabled () > 0
4282 && catching_syscall_number (syscall_number
) > 0)
4285 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4288 ecs
->event_thread
->control
.stop_bpstat
4289 = bpstat_stop_status (get_regcache_aspace (regcache
),
4290 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4292 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4294 /* Catchpoint hit. */
4299 /* If no catchpoint triggered for this, then keep going. */
4304 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4307 fill_in_stop_func (struct gdbarch
*gdbarch
,
4308 struct execution_control_state
*ecs
)
4310 if (!ecs
->stop_func_filled_in
)
4312 /* Don't care about return value; stop_func_start and stop_func_name
4313 will both be 0 if it doesn't work. */
4314 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4315 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4316 ecs
->stop_func_start
4317 += gdbarch_deprecated_function_start_offset (gdbarch
);
4319 if (gdbarch_skip_entrypoint_p (gdbarch
))
4320 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4321 ecs
->stop_func_start
);
4323 ecs
->stop_func_filled_in
= 1;
4328 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4330 static enum stop_kind
4331 get_inferior_stop_soon (ptid_t ptid
)
4333 struct inferior
*inf
= find_inferior_ptid (ptid
);
4335 gdb_assert (inf
!= NULL
);
4336 return inf
->control
.stop_soon
;
4339 /* Wait for one event. Store the resulting waitstatus in WS, and
4340 return the event ptid. */
4343 wait_one (struct target_waitstatus
*ws
)
4346 ptid_t wait_ptid
= minus_one_ptid
;
4348 overlay_cache_invalid
= 1;
4350 /* Flush target cache before starting to handle each event.
4351 Target was running and cache could be stale. This is just a
4352 heuristic. Running threads may modify target memory, but we
4353 don't get any event. */
4354 target_dcache_invalidate ();
4356 if (deprecated_target_wait_hook
)
4357 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4359 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4362 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4367 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4368 instead of the current thread. */
4369 #define THREAD_STOPPED_BY(REASON) \
4371 thread_stopped_by_ ## REASON (ptid_t ptid) \
4373 struct cleanup *old_chain; \
4376 old_chain = save_inferior_ptid (); \
4377 inferior_ptid = ptid; \
4379 res = target_stopped_by_ ## REASON (); \
4381 do_cleanups (old_chain); \
4386 /* Generate thread_stopped_by_watchpoint. */
4387 THREAD_STOPPED_BY (watchpoint
)
4388 /* Generate thread_stopped_by_sw_breakpoint. */
4389 THREAD_STOPPED_BY (sw_breakpoint
)
4390 /* Generate thread_stopped_by_hw_breakpoint. */
4391 THREAD_STOPPED_BY (hw_breakpoint
)
4393 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4396 switch_to_thread_cleanup (void *ptid_p
)
4398 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4400 switch_to_thread (ptid
);
4403 /* Save the thread's event and stop reason to process it later. */
4406 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4408 struct regcache
*regcache
;
4409 struct address_space
*aspace
;
4415 statstr
= target_waitstatus_to_string (ws
);
4416 fprintf_unfiltered (gdb_stdlog
,
4417 "infrun: saving status %s for %d.%ld.%ld\n",
4419 ptid_get_pid (tp
->ptid
),
4420 ptid_get_lwp (tp
->ptid
),
4421 ptid_get_tid (tp
->ptid
));
4425 /* Record for later. */
4426 tp
->suspend
.waitstatus
= *ws
;
4427 tp
->suspend
.waitstatus_pending_p
= 1;
4429 regcache
= get_thread_regcache (tp
->ptid
);
4430 aspace
= get_regcache_aspace (regcache
);
4432 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4433 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4435 CORE_ADDR pc
= regcache_read_pc (regcache
);
4437 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4439 if (thread_stopped_by_watchpoint (tp
->ptid
))
4441 tp
->suspend
.stop_reason
4442 = TARGET_STOPPED_BY_WATCHPOINT
;
4444 else if (target_supports_stopped_by_sw_breakpoint ()
4445 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4447 tp
->suspend
.stop_reason
4448 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4450 else if (target_supports_stopped_by_hw_breakpoint ()
4451 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4453 tp
->suspend
.stop_reason
4454 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4456 else if (!target_supports_stopped_by_hw_breakpoint ()
4457 && hardware_breakpoint_inserted_here_p (aspace
,
4460 tp
->suspend
.stop_reason
4461 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4463 else if (!target_supports_stopped_by_sw_breakpoint ()
4464 && software_breakpoint_inserted_here_p (aspace
,
4467 tp
->suspend
.stop_reason
4468 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4470 else if (!thread_has_single_step_breakpoints_set (tp
)
4471 && currently_stepping (tp
))
4473 tp
->suspend
.stop_reason
4474 = TARGET_STOPPED_BY_SINGLE_STEP
;
4479 /* A cleanup that disables thread create/exit events. */
4482 disable_thread_events (void *arg
)
4484 target_thread_events (0);
4490 stop_all_threads (void)
4492 /* We may need multiple passes to discover all threads. */
4496 struct cleanup
*old_chain
;
4498 gdb_assert (target_is_non_stop_p ());
4501 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4503 entry_ptid
= inferior_ptid
;
4504 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4506 target_thread_events (1);
4507 make_cleanup (disable_thread_events
, NULL
);
4509 /* Request threads to stop, and then wait for the stops. Because
4510 threads we already know about can spawn more threads while we're
4511 trying to stop them, and we only learn about new threads when we
4512 update the thread list, do this in a loop, and keep iterating
4513 until two passes find no threads that need to be stopped. */
4514 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4517 fprintf_unfiltered (gdb_stdlog
,
4518 "infrun: stop_all_threads, pass=%d, "
4519 "iterations=%d\n", pass
, iterations
);
4523 struct target_waitstatus ws
;
4525 struct thread_info
*t
;
4527 update_thread_list ();
4529 /* Go through all threads looking for threads that we need
4530 to tell the target to stop. */
4531 ALL_NON_EXITED_THREADS (t
)
4535 /* If already stopping, don't request a stop again.
4536 We just haven't seen the notification yet. */
4537 if (!t
->stop_requested
)
4540 fprintf_unfiltered (gdb_stdlog
,
4541 "infrun: %s executing, "
4543 target_pid_to_str (t
->ptid
));
4544 target_stop (t
->ptid
);
4545 t
->stop_requested
= 1;
4550 fprintf_unfiltered (gdb_stdlog
,
4551 "infrun: %s executing, "
4552 "already stopping\n",
4553 target_pid_to_str (t
->ptid
));
4556 if (t
->stop_requested
)
4562 fprintf_unfiltered (gdb_stdlog
,
4563 "infrun: %s not executing\n",
4564 target_pid_to_str (t
->ptid
));
4566 /* The thread may be not executing, but still be
4567 resumed with a pending status to process. */
4575 /* If we find new threads on the second iteration, restart
4576 over. We want to see two iterations in a row with all
4581 event_ptid
= wait_one (&ws
);
4582 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4584 /* All resumed threads exited. */
4586 else if (ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4587 || ws
.kind
== TARGET_WAITKIND_EXITED
4588 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4592 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4594 fprintf_unfiltered (gdb_stdlog
,
4595 "infrun: %s exited while "
4596 "stopping threads\n",
4597 target_pid_to_str (ptid
));
4602 struct inferior
*inf
;
4604 t
= find_thread_ptid (event_ptid
);
4606 t
= add_thread (event_ptid
);
4608 t
->stop_requested
= 0;
4611 t
->control
.may_range_step
= 0;
4613 /* This may be the first time we see the inferior report
4615 inf
= find_inferior_ptid (event_ptid
);
4616 if (inf
->needs_setup
)
4618 switch_to_thread_no_regs (t
);
4622 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4623 && ws
.value
.sig
== GDB_SIGNAL_0
)
4625 /* We caught the event that we intended to catch, so
4626 there's no event pending. */
4627 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4628 t
->suspend
.waitstatus_pending_p
= 0;
4630 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4632 /* Add it back to the step-over queue. */
4635 fprintf_unfiltered (gdb_stdlog
,
4636 "infrun: displaced-step of %s "
4637 "canceled: adding back to the "
4638 "step-over queue\n",
4639 target_pid_to_str (t
->ptid
));
4641 t
->control
.trap_expected
= 0;
4642 thread_step_over_chain_enqueue (t
);
4647 enum gdb_signal sig
;
4648 struct regcache
*regcache
;
4654 statstr
= target_waitstatus_to_string (&ws
);
4655 fprintf_unfiltered (gdb_stdlog
,
4656 "infrun: target_wait %s, saving "
4657 "status for %d.%ld.%ld\n",
4659 ptid_get_pid (t
->ptid
),
4660 ptid_get_lwp (t
->ptid
),
4661 ptid_get_tid (t
->ptid
));
4665 /* Record for later. */
4666 save_waitstatus (t
, &ws
);
4668 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4669 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4671 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4673 /* Add it back to the step-over queue. */
4674 t
->control
.trap_expected
= 0;
4675 thread_step_over_chain_enqueue (t
);
4678 regcache
= get_thread_regcache (t
->ptid
);
4679 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4683 fprintf_unfiltered (gdb_stdlog
,
4684 "infrun: saved stop_pc=%s for %s "
4685 "(currently_stepping=%d)\n",
4686 paddress (target_gdbarch (),
4687 t
->suspend
.stop_pc
),
4688 target_pid_to_str (t
->ptid
),
4689 currently_stepping (t
));
4696 do_cleanups (old_chain
);
4699 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4702 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4705 handle_no_resumed (struct execution_control_state
*ecs
)
4707 struct inferior
*inf
;
4708 struct thread_info
*thread
;
4710 if (target_can_async_p ())
4717 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4725 /* There were no unwaited-for children left in the target, but,
4726 we're not synchronously waiting for events either. Just
4730 fprintf_unfiltered (gdb_stdlog
,
4731 "infrun: TARGET_WAITKIND_NO_RESUMED "
4732 "(ignoring: bg)\n");
4733 prepare_to_wait (ecs
);
4738 /* Otherwise, if we were running a synchronous execution command, we
4739 may need to cancel it and give the user back the terminal.
4741 In non-stop mode, the target can't tell whether we've already
4742 consumed previous stop events, so it can end up sending us a
4743 no-resumed event like so:
4745 #0 - thread 1 is left stopped
4747 #1 - thread 2 is resumed and hits breakpoint
4748 -> TARGET_WAITKIND_STOPPED
4750 #2 - thread 3 is resumed and exits
4751 this is the last resumed thread, so
4752 -> TARGET_WAITKIND_NO_RESUMED
4754 #3 - gdb processes stop for thread 2 and decides to re-resume
4757 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4758 thread 2 is now resumed, so the event should be ignored.
4760 IOW, if the stop for thread 2 doesn't end a foreground command,
4761 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4762 event. But it could be that the event meant that thread 2 itself
4763 (or whatever other thread was the last resumed thread) exited.
4765 To address this we refresh the thread list and check whether we
4766 have resumed threads _now_. In the example above, this removes
4767 thread 3 from the thread list. If thread 2 was re-resumed, we
4768 ignore this event. If we find no thread resumed, then we cancel
4769 the synchronous command show "no unwaited-for " to the user. */
4770 update_thread_list ();
4772 ALL_NON_EXITED_THREADS (thread
)
4774 if (thread
->executing
4775 || thread
->suspend
.waitstatus_pending_p
)
4777 /* There were no unwaited-for children left in the target at
4778 some point, but there are now. Just ignore. */
4780 fprintf_unfiltered (gdb_stdlog
,
4781 "infrun: TARGET_WAITKIND_NO_RESUMED "
4782 "(ignoring: found resumed)\n");
4783 prepare_to_wait (ecs
);
4788 /* Note however that we may find no resumed thread because the whole
4789 process exited meanwhile (thus updating the thread list results
4790 in an empty thread list). In this case we know we'll be getting
4791 a process exit event shortly. */
4797 thread
= any_live_thread_of_process (inf
->pid
);
4801 fprintf_unfiltered (gdb_stdlog
,
4802 "infrun: TARGET_WAITKIND_NO_RESUMED "
4803 "(expect process exit)\n");
4804 prepare_to_wait (ecs
);
4809 /* Go ahead and report the event. */
4813 /* Given an execution control state that has been freshly filled in by
4814 an event from the inferior, figure out what it means and take
4817 The alternatives are:
4819 1) stop_waiting and return; to really stop and return to the
4822 2) keep_going and return; to wait for the next event (set
4823 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4827 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4829 enum stop_kind stop_soon
;
4831 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4833 /* We had an event in the inferior, but we are not interested in
4834 handling it at this level. The lower layers have already
4835 done what needs to be done, if anything.
4837 One of the possible circumstances for this is when the
4838 inferior produces output for the console. The inferior has
4839 not stopped, and we are ignoring the event. Another possible
4840 circumstance is any event which the lower level knows will be
4841 reported multiple times without an intervening resume. */
4843 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4844 prepare_to_wait (ecs
);
4848 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4851 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4852 prepare_to_wait (ecs
);
4856 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4857 && handle_no_resumed (ecs
))
4860 /* Cache the last pid/waitstatus. */
4861 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4863 /* Always clear state belonging to the previous time we stopped. */
4864 stop_stack_dummy
= STOP_NONE
;
4866 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4868 /* No unwaited-for children left. IOW, all resumed children
4871 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4873 stop_print_frame
= 0;
4878 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4879 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4881 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4882 /* If it's a new thread, add it to the thread database. */
4883 if (ecs
->event_thread
== NULL
)
4884 ecs
->event_thread
= add_thread (ecs
->ptid
);
4886 /* Disable range stepping. If the next step request could use a
4887 range, this will be end up re-enabled then. */
4888 ecs
->event_thread
->control
.may_range_step
= 0;
4891 /* Dependent on valid ECS->EVENT_THREAD. */
4892 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4894 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4895 reinit_frame_cache ();
4897 breakpoint_retire_moribund ();
4899 /* First, distinguish signals caused by the debugger from signals
4900 that have to do with the program's own actions. Note that
4901 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4902 on the operating system version. Here we detect when a SIGILL or
4903 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4904 something similar for SIGSEGV, since a SIGSEGV will be generated
4905 when we're trying to execute a breakpoint instruction on a
4906 non-executable stack. This happens for call dummy breakpoints
4907 for architectures like SPARC that place call dummies on the
4909 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4910 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4911 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4912 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4914 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4916 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4917 regcache_read_pc (regcache
)))
4920 fprintf_unfiltered (gdb_stdlog
,
4921 "infrun: Treating signal as SIGTRAP\n");
4922 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4926 /* Mark the non-executing threads accordingly. In all-stop, all
4927 threads of all processes are stopped when we get any event
4928 reported. In non-stop mode, only the event thread stops. */
4932 if (!target_is_non_stop_p ())
4933 mark_ptid
= minus_one_ptid
;
4934 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4935 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4937 /* If we're handling a process exit in non-stop mode, even
4938 though threads haven't been deleted yet, one would think
4939 that there is nothing to do, as threads of the dead process
4940 will be soon deleted, and threads of any other process were
4941 left running. However, on some targets, threads survive a
4942 process exit event. E.g., for the "checkpoint" command,
4943 when the current checkpoint/fork exits, linux-fork.c
4944 automatically switches to another fork from within
4945 target_mourn_inferior, by associating the same
4946 inferior/thread to another fork. We haven't mourned yet at
4947 this point, but we must mark any threads left in the
4948 process as not-executing so that finish_thread_state marks
4949 them stopped (in the user's perspective) if/when we present
4950 the stop to the user. */
4951 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4954 mark_ptid
= ecs
->ptid
;
4956 set_executing (mark_ptid
, 0);
4958 /* Likewise the resumed flag. */
4959 set_resumed (mark_ptid
, 0);
4962 switch (ecs
->ws
.kind
)
4964 case TARGET_WAITKIND_LOADED
:
4966 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4967 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4968 context_switch (ecs
->ptid
);
4969 /* Ignore gracefully during startup of the inferior, as it might
4970 be the shell which has just loaded some objects, otherwise
4971 add the symbols for the newly loaded objects. Also ignore at
4972 the beginning of an attach or remote session; we will query
4973 the full list of libraries once the connection is
4976 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4977 if (stop_soon
== NO_STOP_QUIETLY
)
4979 struct regcache
*regcache
;
4981 regcache
= get_thread_regcache (ecs
->ptid
);
4983 handle_solib_event ();
4985 ecs
->event_thread
->control
.stop_bpstat
4986 = bpstat_stop_status (get_regcache_aspace (regcache
),
4987 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4989 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4991 /* A catchpoint triggered. */
4992 process_event_stop_test (ecs
);
4996 /* If requested, stop when the dynamic linker notifies
4997 gdb of events. This allows the user to get control
4998 and place breakpoints in initializer routines for
4999 dynamically loaded objects (among other things). */
5000 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5001 if (stop_on_solib_events
)
5003 /* Make sure we print "Stopped due to solib-event" in
5005 stop_print_frame
= 1;
5012 /* If we are skipping through a shell, or through shared library
5013 loading that we aren't interested in, resume the program. If
5014 we're running the program normally, also resume. */
5015 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5017 /* Loading of shared libraries might have changed breakpoint
5018 addresses. Make sure new breakpoints are inserted. */
5019 if (stop_soon
== NO_STOP_QUIETLY
)
5020 insert_breakpoints ();
5021 resume (GDB_SIGNAL_0
);
5022 prepare_to_wait (ecs
);
5026 /* But stop if we're attaching or setting up a remote
5028 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5029 || stop_soon
== STOP_QUIETLY_REMOTE
)
5032 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5037 internal_error (__FILE__
, __LINE__
,
5038 _("unhandled stop_soon: %d"), (int) stop_soon
);
5040 case TARGET_WAITKIND_SPURIOUS
:
5042 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5043 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5044 context_switch (ecs
->ptid
);
5045 resume (GDB_SIGNAL_0
);
5046 prepare_to_wait (ecs
);
5049 case TARGET_WAITKIND_THREAD_CREATED
:
5051 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5052 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5053 context_switch (ecs
->ptid
);
5054 if (!switch_back_to_stepped_thread (ecs
))
5058 case TARGET_WAITKIND_EXITED
:
5059 case TARGET_WAITKIND_SIGNALLED
:
5062 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5063 fprintf_unfiltered (gdb_stdlog
,
5064 "infrun: TARGET_WAITKIND_EXITED\n");
5066 fprintf_unfiltered (gdb_stdlog
,
5067 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5070 inferior_ptid
= ecs
->ptid
;
5071 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
5072 set_current_program_space (current_inferior ()->pspace
);
5073 handle_vfork_child_exec_or_exit (0);
5074 target_terminal_ours (); /* Must do this before mourn anyway. */
5076 /* Clearing any previous state of convenience variables. */
5077 clear_exit_convenience_vars ();
5079 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5081 /* Record the exit code in the convenience variable $_exitcode, so
5082 that the user can inspect this again later. */
5083 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5084 (LONGEST
) ecs
->ws
.value
.integer
);
5086 /* Also record this in the inferior itself. */
5087 current_inferior ()->has_exit_code
= 1;
5088 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5090 /* Support the --return-child-result option. */
5091 return_child_result_value
= ecs
->ws
.value
.integer
;
5093 observer_notify_exited (ecs
->ws
.value
.integer
);
5097 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5098 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5100 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5102 /* Set the value of the internal variable $_exitsignal,
5103 which holds the signal uncaught by the inferior. */
5104 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5105 gdbarch_gdb_signal_to_target (gdbarch
,
5106 ecs
->ws
.value
.sig
));
5110 /* We don't have access to the target's method used for
5111 converting between signal numbers (GDB's internal
5112 representation <-> target's representation).
5113 Therefore, we cannot do a good job at displaying this
5114 information to the user. It's better to just warn
5115 her about it (if infrun debugging is enabled), and
5118 fprintf_filtered (gdb_stdlog
, _("\
5119 Cannot fill $_exitsignal with the correct signal number.\n"));
5122 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
5125 gdb_flush (gdb_stdout
);
5126 target_mourn_inferior (inferior_ptid
);
5127 stop_print_frame
= 0;
5131 /* The following are the only cases in which we keep going;
5132 the above cases end in a continue or goto. */
5133 case TARGET_WAITKIND_FORKED
:
5134 case TARGET_WAITKIND_VFORKED
:
5137 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5138 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
5140 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
5143 /* Check whether the inferior is displaced stepping. */
5145 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5146 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5148 /* If checking displaced stepping is supported, and thread
5149 ecs->ptid is displaced stepping. */
5150 if (displaced_step_in_progress_thread (ecs
->ptid
))
5152 struct inferior
*parent_inf
5153 = find_inferior_ptid (ecs
->ptid
);
5154 struct regcache
*child_regcache
;
5155 CORE_ADDR parent_pc
;
5157 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5158 indicating that the displaced stepping of syscall instruction
5159 has been done. Perform cleanup for parent process here. Note
5160 that this operation also cleans up the child process for vfork,
5161 because their pages are shared. */
5162 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
5163 /* Start a new step-over in another thread if there's one
5167 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5169 struct displaced_step_inferior_state
*displaced
5170 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
5172 /* Restore scratch pad for child process. */
5173 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
5176 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5177 the child's PC is also within the scratchpad. Set the child's PC
5178 to the parent's PC value, which has already been fixed up.
5179 FIXME: we use the parent's aspace here, although we're touching
5180 the child, because the child hasn't been added to the inferior
5181 list yet at this point. */
5184 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
5186 parent_inf
->aspace
);
5187 /* Read PC value of parent process. */
5188 parent_pc
= regcache_read_pc (regcache
);
5190 if (debug_displaced
)
5191 fprintf_unfiltered (gdb_stdlog
,
5192 "displaced: write child pc from %s to %s\n",
5194 regcache_read_pc (child_regcache
)),
5195 paddress (gdbarch
, parent_pc
));
5197 regcache_write_pc (child_regcache
, parent_pc
);
5201 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5202 context_switch (ecs
->ptid
);
5204 /* Immediately detach breakpoints from the child before there's
5205 any chance of letting the user delete breakpoints from the
5206 breakpoint lists. If we don't do this early, it's easy to
5207 leave left over traps in the child, vis: "break foo; catch
5208 fork; c; <fork>; del; c; <child calls foo>". We only follow
5209 the fork on the last `continue', and by that time the
5210 breakpoint at "foo" is long gone from the breakpoint table.
5211 If we vforked, then we don't need to unpatch here, since both
5212 parent and child are sharing the same memory pages; we'll
5213 need to unpatch at follow/detach time instead to be certain
5214 that new breakpoints added between catchpoint hit time and
5215 vfork follow are detached. */
5216 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5218 /* This won't actually modify the breakpoint list, but will
5219 physically remove the breakpoints from the child. */
5220 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5223 delete_just_stopped_threads_single_step_breakpoints ();
5225 /* In case the event is caught by a catchpoint, remember that
5226 the event is to be followed at the next resume of the thread,
5227 and not immediately. */
5228 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5230 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5232 ecs
->event_thread
->control
.stop_bpstat
5233 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5234 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5236 /* If no catchpoint triggered for this, then keep going. Note
5237 that we're interested in knowing the bpstat actually causes a
5238 stop, not just if it may explain the signal. Software
5239 watchpoints, for example, always appear in the bpstat. */
5240 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5246 = (follow_fork_mode_string
== follow_fork_mode_child
);
5248 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5250 should_resume
= follow_fork ();
5253 child
= ecs
->ws
.value
.related_pid
;
5255 /* At this point, the parent is marked running, and the
5256 child is marked stopped. */
5258 /* If not resuming the parent, mark it stopped. */
5259 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5260 set_running (parent
, 0);
5262 /* If resuming the child, mark it running. */
5263 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5264 set_running (child
, 1);
5266 /* In non-stop mode, also resume the other branch. */
5267 if (!detach_fork
&& (non_stop
5268 || (sched_multi
&& target_is_non_stop_p ())))
5271 switch_to_thread (parent
);
5273 switch_to_thread (child
);
5275 ecs
->event_thread
= inferior_thread ();
5276 ecs
->ptid
= inferior_ptid
;
5281 switch_to_thread (child
);
5283 switch_to_thread (parent
);
5285 ecs
->event_thread
= inferior_thread ();
5286 ecs
->ptid
= inferior_ptid
;
5294 process_event_stop_test (ecs
);
5297 case TARGET_WAITKIND_VFORK_DONE
:
5298 /* Done with the shared memory region. Re-insert breakpoints in
5299 the parent, and keep going. */
5302 fprintf_unfiltered (gdb_stdlog
,
5303 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5305 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5306 context_switch (ecs
->ptid
);
5308 current_inferior ()->waiting_for_vfork_done
= 0;
5309 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5310 /* This also takes care of reinserting breakpoints in the
5311 previously locked inferior. */
5315 case TARGET_WAITKIND_EXECD
:
5317 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5319 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5320 context_switch (ecs
->ptid
);
5322 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5324 /* Do whatever is necessary to the parent branch of the vfork. */
5325 handle_vfork_child_exec_or_exit (1);
5327 /* This causes the eventpoints and symbol table to be reset.
5328 Must do this now, before trying to determine whether to
5330 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5332 /* In follow_exec we may have deleted the original thread and
5333 created a new one. Make sure that the event thread is the
5334 execd thread for that case (this is a nop otherwise). */
5335 ecs
->event_thread
= inferior_thread ();
5337 ecs
->event_thread
->control
.stop_bpstat
5338 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5339 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5341 /* Note that this may be referenced from inside
5342 bpstat_stop_status above, through inferior_has_execd. */
5343 xfree (ecs
->ws
.value
.execd_pathname
);
5344 ecs
->ws
.value
.execd_pathname
= NULL
;
5346 /* If no catchpoint triggered for this, then keep going. */
5347 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5349 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5353 process_event_stop_test (ecs
);
5356 /* Be careful not to try to gather much state about a thread
5357 that's in a syscall. It's frequently a losing proposition. */
5358 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5360 fprintf_unfiltered (gdb_stdlog
,
5361 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5362 /* Getting the current syscall number. */
5363 if (handle_syscall_event (ecs
) == 0)
5364 process_event_stop_test (ecs
);
5367 /* Before examining the threads further, step this thread to
5368 get it entirely out of the syscall. (We get notice of the
5369 event when the thread is just on the verge of exiting a
5370 syscall. Stepping one instruction seems to get it back
5372 case TARGET_WAITKIND_SYSCALL_RETURN
:
5374 fprintf_unfiltered (gdb_stdlog
,
5375 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5376 if (handle_syscall_event (ecs
) == 0)
5377 process_event_stop_test (ecs
);
5380 case TARGET_WAITKIND_STOPPED
:
5382 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5383 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5384 handle_signal_stop (ecs
);
5387 case TARGET_WAITKIND_NO_HISTORY
:
5389 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5390 /* Reverse execution: target ran out of history info. */
5392 /* Switch to the stopped thread. */
5393 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5394 context_switch (ecs
->ptid
);
5396 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5398 delete_just_stopped_threads_single_step_breakpoints ();
5399 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5400 observer_notify_no_history ();
5406 /* A wrapper around handle_inferior_event_1, which also makes sure
5407 that all temporary struct value objects that were created during
5408 the handling of the event get deleted at the end. */
5411 handle_inferior_event (struct execution_control_state
*ecs
)
5413 struct value
*mark
= value_mark ();
5415 handle_inferior_event_1 (ecs
);
5416 /* Purge all temporary values created during the event handling,
5417 as it could be a long time before we return to the command level
5418 where such values would otherwise be purged. */
5419 value_free_to_mark (mark
);
5422 /* Restart threads back to what they were trying to do back when we
5423 paused them for an in-line step-over. The EVENT_THREAD thread is
5427 restart_threads (struct thread_info
*event_thread
)
5429 struct thread_info
*tp
;
5431 /* In case the instruction just stepped spawned a new thread. */
5432 update_thread_list ();
5434 ALL_NON_EXITED_THREADS (tp
)
5436 if (tp
== event_thread
)
5439 fprintf_unfiltered (gdb_stdlog
,
5440 "infrun: restart threads: "
5441 "[%s] is event thread\n",
5442 target_pid_to_str (tp
->ptid
));
5446 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5449 fprintf_unfiltered (gdb_stdlog
,
5450 "infrun: restart threads: "
5451 "[%s] not meant to be running\n",
5452 target_pid_to_str (tp
->ptid
));
5459 fprintf_unfiltered (gdb_stdlog
,
5460 "infrun: restart threads: [%s] resumed\n",
5461 target_pid_to_str (tp
->ptid
));
5462 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5466 if (thread_is_in_step_over_chain (tp
))
5469 fprintf_unfiltered (gdb_stdlog
,
5470 "infrun: restart threads: "
5471 "[%s] needs step-over\n",
5472 target_pid_to_str (tp
->ptid
));
5473 gdb_assert (!tp
->resumed
);
5478 if (tp
->suspend
.waitstatus_pending_p
)
5481 fprintf_unfiltered (gdb_stdlog
,
5482 "infrun: restart threads: "
5483 "[%s] has pending status\n",
5484 target_pid_to_str (tp
->ptid
));
5489 /* If some thread needs to start a step-over at this point, it
5490 should still be in the step-over queue, and thus skipped
5492 if (thread_still_needs_step_over (tp
))
5494 internal_error (__FILE__
, __LINE__
,
5495 "thread [%s] needs a step-over, but not in "
5496 "step-over queue\n",
5497 target_pid_to_str (tp
->ptid
));
5500 if (currently_stepping (tp
))
5503 fprintf_unfiltered (gdb_stdlog
,
5504 "infrun: restart threads: [%s] was stepping\n",
5505 target_pid_to_str (tp
->ptid
));
5506 keep_going_stepped_thread (tp
);
5510 struct execution_control_state ecss
;
5511 struct execution_control_state
*ecs
= &ecss
;
5514 fprintf_unfiltered (gdb_stdlog
,
5515 "infrun: restart threads: [%s] continuing\n",
5516 target_pid_to_str (tp
->ptid
));
5517 reset_ecs (ecs
, tp
);
5518 switch_to_thread (tp
->ptid
);
5519 keep_going_pass_signal (ecs
);
5524 /* Callback for iterate_over_threads. Find a resumed thread that has
5525 a pending waitstatus. */
5528 resumed_thread_with_pending_status (struct thread_info
*tp
,
5532 && tp
->suspend
.waitstatus_pending_p
);
5535 /* Called when we get an event that may finish an in-line or
5536 out-of-line (displaced stepping) step-over started previously.
5537 Return true if the event is processed and we should go back to the
5538 event loop; false if the caller should continue processing the
5542 finish_step_over (struct execution_control_state
*ecs
)
5544 int had_step_over_info
;
5546 displaced_step_fixup (ecs
->ptid
,
5547 ecs
->event_thread
->suspend
.stop_signal
);
5549 had_step_over_info
= step_over_info_valid_p ();
5551 if (had_step_over_info
)
5553 /* If we're stepping over a breakpoint with all threads locked,
5554 then only the thread that was stepped should be reporting
5556 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5558 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5559 clear_step_over_info ();
5562 if (!target_is_non_stop_p ())
5565 /* Start a new step-over in another thread if there's one that
5569 /* If we were stepping over a breakpoint before, and haven't started
5570 a new in-line step-over sequence, then restart all other threads
5571 (except the event thread). We can't do this in all-stop, as then
5572 e.g., we wouldn't be able to issue any other remote packet until
5573 these other threads stop. */
5574 if (had_step_over_info
&& !step_over_info_valid_p ())
5576 struct thread_info
*pending
;
5578 /* If we only have threads with pending statuses, the restart
5579 below won't restart any thread and so nothing re-inserts the
5580 breakpoint we just stepped over. But we need it inserted
5581 when we later process the pending events, otherwise if
5582 another thread has a pending event for this breakpoint too,
5583 we'd discard its event (because the breakpoint that
5584 originally caused the event was no longer inserted). */
5585 context_switch (ecs
->ptid
);
5586 insert_breakpoints ();
5588 restart_threads (ecs
->event_thread
);
5590 /* If we have events pending, go through handle_inferior_event
5591 again, picking up a pending event at random. This avoids
5592 thread starvation. */
5594 /* But not if we just stepped over a watchpoint in order to let
5595 the instruction execute so we can evaluate its expression.
5596 The set of watchpoints that triggered is recorded in the
5597 breakpoint objects themselves (see bp->watchpoint_triggered).
5598 If we processed another event first, that other event could
5599 clobber this info. */
5600 if (ecs
->event_thread
->stepping_over_watchpoint
)
5603 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5605 if (pending
!= NULL
)
5607 struct thread_info
*tp
= ecs
->event_thread
;
5608 struct regcache
*regcache
;
5612 fprintf_unfiltered (gdb_stdlog
,
5613 "infrun: found resumed threads with "
5614 "pending events, saving status\n");
5617 gdb_assert (pending
!= tp
);
5619 /* Record the event thread's event for later. */
5620 save_waitstatus (tp
, &ecs
->ws
);
5621 /* This was cleared early, by handle_inferior_event. Set it
5622 so this pending event is considered by
5626 gdb_assert (!tp
->executing
);
5628 regcache
= get_thread_regcache (tp
->ptid
);
5629 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5633 fprintf_unfiltered (gdb_stdlog
,
5634 "infrun: saved stop_pc=%s for %s "
5635 "(currently_stepping=%d)\n",
5636 paddress (target_gdbarch (),
5637 tp
->suspend
.stop_pc
),
5638 target_pid_to_str (tp
->ptid
),
5639 currently_stepping (tp
));
5642 /* This in-line step-over finished; clear this so we won't
5643 start a new one. This is what handle_signal_stop would
5644 do, if we returned false. */
5645 tp
->stepping_over_breakpoint
= 0;
5647 /* Wake up the event loop again. */
5648 mark_async_event_handler (infrun_async_inferior_event_token
);
5650 prepare_to_wait (ecs
);
5658 /* Come here when the program has stopped with a signal. */
5661 handle_signal_stop (struct execution_control_state
*ecs
)
5663 struct frame_info
*frame
;
5664 struct gdbarch
*gdbarch
;
5665 int stopped_by_watchpoint
;
5666 enum stop_kind stop_soon
;
5669 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5671 /* Do we need to clean up the state of a thread that has
5672 completed a displaced single-step? (Doing so usually affects
5673 the PC, so do it here, before we set stop_pc.) */
5674 if (finish_step_over (ecs
))
5677 /* If we either finished a single-step or hit a breakpoint, but
5678 the user wanted this thread to be stopped, pretend we got a
5679 SIG0 (generic unsignaled stop). */
5680 if (ecs
->event_thread
->stop_requested
5681 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5682 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5684 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5688 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5689 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5690 struct cleanup
*old_chain
= save_inferior_ptid ();
5692 inferior_ptid
= ecs
->ptid
;
5694 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5695 paddress (gdbarch
, stop_pc
));
5696 if (target_stopped_by_watchpoint ())
5700 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5702 if (target_stopped_data_address (¤t_target
, &addr
))
5703 fprintf_unfiltered (gdb_stdlog
,
5704 "infrun: stopped data address = %s\n",
5705 paddress (gdbarch
, addr
));
5707 fprintf_unfiltered (gdb_stdlog
,
5708 "infrun: (no data address available)\n");
5711 do_cleanups (old_chain
);
5714 /* This is originated from start_remote(), start_inferior() and
5715 shared libraries hook functions. */
5716 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5717 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5719 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5720 context_switch (ecs
->ptid
);
5722 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5723 stop_print_frame
= 1;
5728 /* This originates from attach_command(). We need to overwrite
5729 the stop_signal here, because some kernels don't ignore a
5730 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5731 See more comments in inferior.h. On the other hand, if we
5732 get a non-SIGSTOP, report it to the user - assume the backend
5733 will handle the SIGSTOP if it should show up later.
5735 Also consider that the attach is complete when we see a
5736 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5737 target extended-remote report it instead of a SIGSTOP
5738 (e.g. gdbserver). We already rely on SIGTRAP being our
5739 signal, so this is no exception.
5741 Also consider that the attach is complete when we see a
5742 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5743 the target to stop all threads of the inferior, in case the
5744 low level attach operation doesn't stop them implicitly. If
5745 they weren't stopped implicitly, then the stub will report a
5746 GDB_SIGNAL_0, meaning: stopped for no particular reason
5747 other than GDB's request. */
5748 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5749 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5750 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5751 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5753 stop_print_frame
= 1;
5755 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5759 /* See if something interesting happened to the non-current thread. If
5760 so, then switch to that thread. */
5761 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5764 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5766 context_switch (ecs
->ptid
);
5768 if (deprecated_context_hook
)
5769 deprecated_context_hook (ptid_to_global_thread_id (ecs
->ptid
));
5772 /* At this point, get hold of the now-current thread's frame. */
5773 frame
= get_current_frame ();
5774 gdbarch
= get_frame_arch (frame
);
5776 /* Pull the single step breakpoints out of the target. */
5777 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5779 struct regcache
*regcache
;
5780 struct address_space
*aspace
;
5783 regcache
= get_thread_regcache (ecs
->ptid
);
5784 aspace
= get_regcache_aspace (regcache
);
5785 pc
= regcache_read_pc (regcache
);
5787 /* However, before doing so, if this single-step breakpoint was
5788 actually for another thread, set this thread up for moving
5790 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5793 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5797 fprintf_unfiltered (gdb_stdlog
,
5798 "infrun: [%s] hit another thread's "
5799 "single-step breakpoint\n",
5800 target_pid_to_str (ecs
->ptid
));
5802 ecs
->hit_singlestep_breakpoint
= 1;
5809 fprintf_unfiltered (gdb_stdlog
,
5810 "infrun: [%s] hit its "
5811 "single-step breakpoint\n",
5812 target_pid_to_str (ecs
->ptid
));
5816 delete_just_stopped_threads_single_step_breakpoints ();
5818 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5819 && ecs
->event_thread
->control
.trap_expected
5820 && ecs
->event_thread
->stepping_over_watchpoint
)
5821 stopped_by_watchpoint
= 0;
5823 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5825 /* If necessary, step over this watchpoint. We'll be back to display
5827 if (stopped_by_watchpoint
5828 && (target_have_steppable_watchpoint
5829 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5831 /* At this point, we are stopped at an instruction which has
5832 attempted to write to a piece of memory under control of
5833 a watchpoint. The instruction hasn't actually executed
5834 yet. If we were to evaluate the watchpoint expression
5835 now, we would get the old value, and therefore no change
5836 would seem to have occurred.
5838 In order to make watchpoints work `right', we really need
5839 to complete the memory write, and then evaluate the
5840 watchpoint expression. We do this by single-stepping the
5843 It may not be necessary to disable the watchpoint to step over
5844 it. For example, the PA can (with some kernel cooperation)
5845 single step over a watchpoint without disabling the watchpoint.
5847 It is far more common to need to disable a watchpoint to step
5848 the inferior over it. If we have non-steppable watchpoints,
5849 we must disable the current watchpoint; it's simplest to
5850 disable all watchpoints.
5852 Any breakpoint at PC must also be stepped over -- if there's
5853 one, it will have already triggered before the watchpoint
5854 triggered, and we either already reported it to the user, or
5855 it didn't cause a stop and we called keep_going. In either
5856 case, if there was a breakpoint at PC, we must be trying to
5858 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5863 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5864 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5865 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5866 ecs
->event_thread
->control
.stop_step
= 0;
5867 stop_print_frame
= 1;
5868 stopped_by_random_signal
= 0;
5870 /* Hide inlined functions starting here, unless we just performed stepi or
5871 nexti. After stepi and nexti, always show the innermost frame (not any
5872 inline function call sites). */
5873 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5875 struct address_space
*aspace
=
5876 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5878 /* skip_inline_frames is expensive, so we avoid it if we can
5879 determine that the address is one where functions cannot have
5880 been inlined. This improves performance with inferiors that
5881 load a lot of shared libraries, because the solib event
5882 breakpoint is defined as the address of a function (i.e. not
5883 inline). Note that we have to check the previous PC as well
5884 as the current one to catch cases when we have just
5885 single-stepped off a breakpoint prior to reinstating it.
5886 Note that we're assuming that the code we single-step to is
5887 not inline, but that's not definitive: there's nothing
5888 preventing the event breakpoint function from containing
5889 inlined code, and the single-step ending up there. If the
5890 user had set a breakpoint on that inlined code, the missing
5891 skip_inline_frames call would break things. Fortunately
5892 that's an extremely unlikely scenario. */
5893 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5894 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5895 && ecs
->event_thread
->control
.trap_expected
5896 && pc_at_non_inline_function (aspace
,
5897 ecs
->event_thread
->prev_pc
,
5900 skip_inline_frames (ecs
->ptid
);
5902 /* Re-fetch current thread's frame in case that invalidated
5904 frame
= get_current_frame ();
5905 gdbarch
= get_frame_arch (frame
);
5909 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5910 && ecs
->event_thread
->control
.trap_expected
5911 && gdbarch_single_step_through_delay_p (gdbarch
)
5912 && currently_stepping (ecs
->event_thread
))
5914 /* We're trying to step off a breakpoint. Turns out that we're
5915 also on an instruction that needs to be stepped multiple
5916 times before it's been fully executing. E.g., architectures
5917 with a delay slot. It needs to be stepped twice, once for
5918 the instruction and once for the delay slot. */
5919 int step_through_delay
5920 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5922 if (debug_infrun
&& step_through_delay
)
5923 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5924 if (ecs
->event_thread
->control
.step_range_end
== 0
5925 && step_through_delay
)
5927 /* The user issued a continue when stopped at a breakpoint.
5928 Set up for another trap and get out of here. */
5929 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5933 else if (step_through_delay
)
5935 /* The user issued a step when stopped at a breakpoint.
5936 Maybe we should stop, maybe we should not - the delay
5937 slot *might* correspond to a line of source. In any
5938 case, don't decide that here, just set
5939 ecs->stepping_over_breakpoint, making sure we
5940 single-step again before breakpoints are re-inserted. */
5941 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5945 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5946 handles this event. */
5947 ecs
->event_thread
->control
.stop_bpstat
5948 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5949 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5951 /* Following in case break condition called a
5953 stop_print_frame
= 1;
5955 /* This is where we handle "moribund" watchpoints. Unlike
5956 software breakpoints traps, hardware watchpoint traps are
5957 always distinguishable from random traps. If no high-level
5958 watchpoint is associated with the reported stop data address
5959 anymore, then the bpstat does not explain the signal ---
5960 simply make sure to ignore it if `stopped_by_watchpoint' is
5964 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5965 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5967 && stopped_by_watchpoint
)
5968 fprintf_unfiltered (gdb_stdlog
,
5969 "infrun: no user watchpoint explains "
5970 "watchpoint SIGTRAP, ignoring\n");
5972 /* NOTE: cagney/2003-03-29: These checks for a random signal
5973 at one stage in the past included checks for an inferior
5974 function call's call dummy's return breakpoint. The original
5975 comment, that went with the test, read:
5977 ``End of a stack dummy. Some systems (e.g. Sony news) give
5978 another signal besides SIGTRAP, so check here as well as
5981 If someone ever tries to get call dummys on a
5982 non-executable stack to work (where the target would stop
5983 with something like a SIGSEGV), then those tests might need
5984 to be re-instated. Given, however, that the tests were only
5985 enabled when momentary breakpoints were not being used, I
5986 suspect that it won't be the case.
5988 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5989 be necessary for call dummies on a non-executable stack on
5992 /* See if the breakpoints module can explain the signal. */
5994 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5995 ecs
->event_thread
->suspend
.stop_signal
);
5997 /* Maybe this was a trap for a software breakpoint that has since
5999 if (random_signal
&& target_stopped_by_sw_breakpoint ())
6001 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
6003 struct regcache
*regcache
;
6006 /* Re-adjust PC to what the program would see if GDB was not
6008 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
6009 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6012 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
6014 if (record_full_is_used ())
6015 record_full_gdb_operation_disable_set ();
6017 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
6019 do_cleanups (old_cleanups
);
6024 /* A delayed software breakpoint event. Ignore the trap. */
6026 fprintf_unfiltered (gdb_stdlog
,
6027 "infrun: delayed software breakpoint "
6028 "trap, ignoring\n");
6033 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6034 has since been removed. */
6035 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6037 /* A delayed hardware breakpoint event. Ignore the trap. */
6039 fprintf_unfiltered (gdb_stdlog
,
6040 "infrun: delayed hardware breakpoint/watchpoint "
6041 "trap, ignoring\n");
6045 /* If not, perhaps stepping/nexting can. */
6047 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6048 && currently_stepping (ecs
->event_thread
));
6050 /* Perhaps the thread hit a single-step breakpoint of _another_
6051 thread. Single-step breakpoints are transparent to the
6052 breakpoints module. */
6054 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6056 /* No? Perhaps we got a moribund watchpoint. */
6058 random_signal
= !stopped_by_watchpoint
;
6060 /* For the program's own signals, act according to
6061 the signal handling tables. */
6065 /* Signal not for debugging purposes. */
6066 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
6067 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6070 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
6071 gdb_signal_to_symbol_string (stop_signal
));
6073 stopped_by_random_signal
= 1;
6075 /* Always stop on signals if we're either just gaining control
6076 of the program, or the user explicitly requested this thread
6077 to remain stopped. */
6078 if (stop_soon
!= NO_STOP_QUIETLY
6079 || ecs
->event_thread
->stop_requested
6081 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
6087 /* Notify observers the signal has "handle print" set. Note we
6088 returned early above if stopping; normal_stop handles the
6089 printing in that case. */
6090 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6092 /* The signal table tells us to print about this signal. */
6093 target_terminal_ours_for_output ();
6094 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
6095 target_terminal_inferior ();
6098 /* Clear the signal if it should not be passed. */
6099 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6100 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6102 if (ecs
->event_thread
->prev_pc
== stop_pc
6103 && ecs
->event_thread
->control
.trap_expected
6104 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6108 /* We were just starting a new sequence, attempting to
6109 single-step off of a breakpoint and expecting a SIGTRAP.
6110 Instead this signal arrives. This signal will take us out
6111 of the stepping range so GDB needs to remember to, when
6112 the signal handler returns, resume stepping off that
6114 /* To simplify things, "continue" is forced to use the same
6115 code paths as single-step - set a breakpoint at the
6116 signal return address and then, once hit, step off that
6119 fprintf_unfiltered (gdb_stdlog
,
6120 "infrun: signal arrived while stepping over "
6123 was_in_line
= step_over_info_valid_p ();
6124 clear_step_over_info ();
6125 insert_hp_step_resume_breakpoint_at_frame (frame
);
6126 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6127 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6128 ecs
->event_thread
->control
.trap_expected
= 0;
6130 if (target_is_non_stop_p ())
6132 /* Either "set non-stop" is "on", or the target is
6133 always in non-stop mode. In this case, we have a bit
6134 more work to do. Resume the current thread, and if
6135 we had paused all threads, restart them while the
6136 signal handler runs. */
6141 restart_threads (ecs
->event_thread
);
6143 else if (debug_infrun
)
6145 fprintf_unfiltered (gdb_stdlog
,
6146 "infrun: no need to restart threads\n");
6151 /* If we were nexting/stepping some other thread, switch to
6152 it, so that we don't continue it, losing control. */
6153 if (!switch_back_to_stepped_thread (ecs
))
6158 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6159 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6160 || ecs
->event_thread
->control
.step_range_end
== 1)
6161 && frame_id_eq (get_stack_frame_id (frame
),
6162 ecs
->event_thread
->control
.step_stack_frame_id
)
6163 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6165 /* The inferior is about to take a signal that will take it
6166 out of the single step range. Set a breakpoint at the
6167 current PC (which is presumably where the signal handler
6168 will eventually return) and then allow the inferior to
6171 Note that this is only needed for a signal delivered
6172 while in the single-step range. Nested signals aren't a
6173 problem as they eventually all return. */
6175 fprintf_unfiltered (gdb_stdlog
,
6176 "infrun: signal may take us out of "
6177 "single-step range\n");
6179 clear_step_over_info ();
6180 insert_hp_step_resume_breakpoint_at_frame (frame
);
6181 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6182 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6183 ecs
->event_thread
->control
.trap_expected
= 0;
6188 /* Note: step_resume_breakpoint may be non-NULL. This occures
6189 when either there's a nested signal, or when there's a
6190 pending signal enabled just as the signal handler returns
6191 (leaving the inferior at the step-resume-breakpoint without
6192 actually executing it). Either way continue until the
6193 breakpoint is really hit. */
6195 if (!switch_back_to_stepped_thread (ecs
))
6198 fprintf_unfiltered (gdb_stdlog
,
6199 "infrun: random signal, keep going\n");
6206 process_event_stop_test (ecs
);
6209 /* Come here when we've got some debug event / signal we can explain
6210 (IOW, not a random signal), and test whether it should cause a
6211 stop, or whether we should resume the inferior (transparently).
6212 E.g., could be a breakpoint whose condition evaluates false; we
6213 could be still stepping within the line; etc. */
6216 process_event_stop_test (struct execution_control_state
*ecs
)
6218 struct symtab_and_line stop_pc_sal
;
6219 struct frame_info
*frame
;
6220 struct gdbarch
*gdbarch
;
6221 CORE_ADDR jmp_buf_pc
;
6222 struct bpstat_what what
;
6224 /* Handle cases caused by hitting a breakpoint. */
6226 frame
= get_current_frame ();
6227 gdbarch
= get_frame_arch (frame
);
6229 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6231 if (what
.call_dummy
)
6233 stop_stack_dummy
= what
.call_dummy
;
6236 /* A few breakpoint types have callbacks associated (e.g.,
6237 bp_jit_event). Run them now. */
6238 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6240 /* If we hit an internal event that triggers symbol changes, the
6241 current frame will be invalidated within bpstat_what (e.g., if we
6242 hit an internal solib event). Re-fetch it. */
6243 frame
= get_current_frame ();
6244 gdbarch
= get_frame_arch (frame
);
6246 switch (what
.main_action
)
6248 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6249 /* If we hit the breakpoint at longjmp while stepping, we
6250 install a momentary breakpoint at the target of the
6254 fprintf_unfiltered (gdb_stdlog
,
6255 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6257 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6259 if (what
.is_longjmp
)
6261 struct value
*arg_value
;
6263 /* If we set the longjmp breakpoint via a SystemTap probe,
6264 then use it to extract the arguments. The destination PC
6265 is the third argument to the probe. */
6266 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6269 jmp_buf_pc
= value_as_address (arg_value
);
6270 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6272 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6273 || !gdbarch_get_longjmp_target (gdbarch
,
6274 frame
, &jmp_buf_pc
))
6277 fprintf_unfiltered (gdb_stdlog
,
6278 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6279 "(!gdbarch_get_longjmp_target)\n");
6284 /* Insert a breakpoint at resume address. */
6285 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6288 check_exception_resume (ecs
, frame
);
6292 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6294 struct frame_info
*init_frame
;
6296 /* There are several cases to consider.
6298 1. The initiating frame no longer exists. In this case we
6299 must stop, because the exception or longjmp has gone too
6302 2. The initiating frame exists, and is the same as the
6303 current frame. We stop, because the exception or longjmp
6306 3. The initiating frame exists and is different from the
6307 current frame. This means the exception or longjmp has
6308 been caught beneath the initiating frame, so keep going.
6310 4. longjmp breakpoint has been placed just to protect
6311 against stale dummy frames and user is not interested in
6312 stopping around longjmps. */
6315 fprintf_unfiltered (gdb_stdlog
,
6316 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6318 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6320 delete_exception_resume_breakpoint (ecs
->event_thread
);
6322 if (what
.is_longjmp
)
6324 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6326 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6334 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6338 struct frame_id current_id
6339 = get_frame_id (get_current_frame ());
6340 if (frame_id_eq (current_id
,
6341 ecs
->event_thread
->initiating_frame
))
6343 /* Case 2. Fall through. */
6353 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6355 delete_step_resume_breakpoint (ecs
->event_thread
);
6357 end_stepping_range (ecs
);
6361 case BPSTAT_WHAT_SINGLE
:
6363 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6364 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6365 /* Still need to check other stuff, at least the case where we
6366 are stepping and step out of the right range. */
6369 case BPSTAT_WHAT_STEP_RESUME
:
6371 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6373 delete_step_resume_breakpoint (ecs
->event_thread
);
6374 if (ecs
->event_thread
->control
.proceed_to_finish
6375 && execution_direction
== EXEC_REVERSE
)
6377 struct thread_info
*tp
= ecs
->event_thread
;
6379 /* We are finishing a function in reverse, and just hit the
6380 step-resume breakpoint at the start address of the
6381 function, and we're almost there -- just need to back up
6382 by one more single-step, which should take us back to the
6384 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6388 fill_in_stop_func (gdbarch
, ecs
);
6389 if (stop_pc
== ecs
->stop_func_start
6390 && execution_direction
== EXEC_REVERSE
)
6392 /* We are stepping over a function call in reverse, and just
6393 hit the step-resume breakpoint at the start address of
6394 the function. Go back to single-stepping, which should
6395 take us back to the function call. */
6396 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6402 case BPSTAT_WHAT_STOP_NOISY
:
6404 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6405 stop_print_frame
= 1;
6407 /* Assume the thread stopped for a breapoint. We'll still check
6408 whether a/the breakpoint is there when the thread is next
6410 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6415 case BPSTAT_WHAT_STOP_SILENT
:
6417 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6418 stop_print_frame
= 0;
6420 /* Assume the thread stopped for a breapoint. We'll still check
6421 whether a/the breakpoint is there when the thread is next
6423 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6427 case BPSTAT_WHAT_HP_STEP_RESUME
:
6429 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6431 delete_step_resume_breakpoint (ecs
->event_thread
);
6432 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6434 /* Back when the step-resume breakpoint was inserted, we
6435 were trying to single-step off a breakpoint. Go back to
6437 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6438 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6444 case BPSTAT_WHAT_KEEP_CHECKING
:
6448 /* If we stepped a permanent breakpoint and we had a high priority
6449 step-resume breakpoint for the address we stepped, but we didn't
6450 hit it, then we must have stepped into the signal handler. The
6451 step-resume was only necessary to catch the case of _not_
6452 stepping into the handler, so delete it, and fall through to
6453 checking whether the step finished. */
6454 if (ecs
->event_thread
->stepped_breakpoint
)
6456 struct breakpoint
*sr_bp
6457 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6460 && sr_bp
->loc
->permanent
6461 && sr_bp
->type
== bp_hp_step_resume
6462 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6465 fprintf_unfiltered (gdb_stdlog
,
6466 "infrun: stepped permanent breakpoint, stopped in "
6468 delete_step_resume_breakpoint (ecs
->event_thread
);
6469 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6473 /* We come here if we hit a breakpoint but should not stop for it.
6474 Possibly we also were stepping and should stop for that. So fall
6475 through and test for stepping. But, if not stepping, do not
6478 /* In all-stop mode, if we're currently stepping but have stopped in
6479 some other thread, we need to switch back to the stepped thread. */
6480 if (switch_back_to_stepped_thread (ecs
))
6483 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6486 fprintf_unfiltered (gdb_stdlog
,
6487 "infrun: step-resume breakpoint is inserted\n");
6489 /* Having a step-resume breakpoint overrides anything
6490 else having to do with stepping commands until
6491 that breakpoint is reached. */
6496 if (ecs
->event_thread
->control
.step_range_end
== 0)
6499 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6500 /* Likewise if we aren't even stepping. */
6505 /* Re-fetch current thread's frame in case the code above caused
6506 the frame cache to be re-initialized, making our FRAME variable
6507 a dangling pointer. */
6508 frame
= get_current_frame ();
6509 gdbarch
= get_frame_arch (frame
);
6510 fill_in_stop_func (gdbarch
, ecs
);
6512 /* If stepping through a line, keep going if still within it.
6514 Note that step_range_end is the address of the first instruction
6515 beyond the step range, and NOT the address of the last instruction
6518 Note also that during reverse execution, we may be stepping
6519 through a function epilogue and therefore must detect when
6520 the current-frame changes in the middle of a line. */
6522 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6523 && (execution_direction
!= EXEC_REVERSE
6524 || frame_id_eq (get_frame_id (frame
),
6525 ecs
->event_thread
->control
.step_frame_id
)))
6529 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6530 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6531 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6533 /* Tentatively re-enable range stepping; `resume' disables it if
6534 necessary (e.g., if we're stepping over a breakpoint or we
6535 have software watchpoints). */
6536 ecs
->event_thread
->control
.may_range_step
= 1;
6538 /* When stepping backward, stop at beginning of line range
6539 (unless it's the function entry point, in which case
6540 keep going back to the call point). */
6541 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6542 && stop_pc
!= ecs
->stop_func_start
6543 && execution_direction
== EXEC_REVERSE
)
6544 end_stepping_range (ecs
);
6551 /* We stepped out of the stepping range. */
6553 /* If we are stepping at the source level and entered the runtime
6554 loader dynamic symbol resolution code...
6556 EXEC_FORWARD: we keep on single stepping until we exit the run
6557 time loader code and reach the callee's address.
6559 EXEC_REVERSE: we've already executed the callee (backward), and
6560 the runtime loader code is handled just like any other
6561 undebuggable function call. Now we need only keep stepping
6562 backward through the trampoline code, and that's handled further
6563 down, so there is nothing for us to do here. */
6565 if (execution_direction
!= EXEC_REVERSE
6566 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6567 && in_solib_dynsym_resolve_code (stop_pc
))
6569 CORE_ADDR pc_after_resolver
=
6570 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6573 fprintf_unfiltered (gdb_stdlog
,
6574 "infrun: stepped into dynsym resolve code\n");
6576 if (pc_after_resolver
)
6578 /* Set up a step-resume breakpoint at the address
6579 indicated by SKIP_SOLIB_RESOLVER. */
6580 struct symtab_and_line sr_sal
;
6583 sr_sal
.pc
= pc_after_resolver
;
6584 sr_sal
.pspace
= get_frame_program_space (frame
);
6586 insert_step_resume_breakpoint_at_sal (gdbarch
,
6587 sr_sal
, null_frame_id
);
6594 if (ecs
->event_thread
->control
.step_range_end
!= 1
6595 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6596 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6597 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6600 fprintf_unfiltered (gdb_stdlog
,
6601 "infrun: stepped into signal trampoline\n");
6602 /* The inferior, while doing a "step" or "next", has ended up in
6603 a signal trampoline (either by a signal being delivered or by
6604 the signal handler returning). Just single-step until the
6605 inferior leaves the trampoline (either by calling the handler
6611 /* If we're in the return path from a shared library trampoline,
6612 we want to proceed through the trampoline when stepping. */
6613 /* macro/2012-04-25: This needs to come before the subroutine
6614 call check below as on some targets return trampolines look
6615 like subroutine calls (MIPS16 return thunks). */
6616 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6617 stop_pc
, ecs
->stop_func_name
)
6618 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6620 /* Determine where this trampoline returns. */
6621 CORE_ADDR real_stop_pc
;
6623 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6626 fprintf_unfiltered (gdb_stdlog
,
6627 "infrun: stepped into solib return tramp\n");
6629 /* Only proceed through if we know where it's going. */
6632 /* And put the step-breakpoint there and go until there. */
6633 struct symtab_and_line sr_sal
;
6635 init_sal (&sr_sal
); /* initialize to zeroes */
6636 sr_sal
.pc
= real_stop_pc
;
6637 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6638 sr_sal
.pspace
= get_frame_program_space (frame
);
6640 /* Do not specify what the fp should be when we stop since
6641 on some machines the prologue is where the new fp value
6643 insert_step_resume_breakpoint_at_sal (gdbarch
,
6644 sr_sal
, null_frame_id
);
6646 /* Restart without fiddling with the step ranges or
6653 /* Check for subroutine calls. The check for the current frame
6654 equalling the step ID is not necessary - the check of the
6655 previous frame's ID is sufficient - but it is a common case and
6656 cheaper than checking the previous frame's ID.
6658 NOTE: frame_id_eq will never report two invalid frame IDs as
6659 being equal, so to get into this block, both the current and
6660 previous frame must have valid frame IDs. */
6661 /* The outer_frame_id check is a heuristic to detect stepping
6662 through startup code. If we step over an instruction which
6663 sets the stack pointer from an invalid value to a valid value,
6664 we may detect that as a subroutine call from the mythical
6665 "outermost" function. This could be fixed by marking
6666 outermost frames as !stack_p,code_p,special_p. Then the
6667 initial outermost frame, before sp was valid, would
6668 have code_addr == &_start. See the comment in frame_id_eq
6670 if (!frame_id_eq (get_stack_frame_id (frame
),
6671 ecs
->event_thread
->control
.step_stack_frame_id
)
6672 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6673 ecs
->event_thread
->control
.step_stack_frame_id
)
6674 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6676 || (ecs
->event_thread
->control
.step_start_function
6677 != find_pc_function (stop_pc
)))))
6679 CORE_ADDR real_stop_pc
;
6682 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6684 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6686 /* I presume that step_over_calls is only 0 when we're
6687 supposed to be stepping at the assembly language level
6688 ("stepi"). Just stop. */
6689 /* And this works the same backward as frontward. MVS */
6690 end_stepping_range (ecs
);
6694 /* Reverse stepping through solib trampolines. */
6696 if (execution_direction
== EXEC_REVERSE
6697 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6698 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6699 || (ecs
->stop_func_start
== 0
6700 && in_solib_dynsym_resolve_code (stop_pc
))))
6702 /* Any solib trampoline code can be handled in reverse
6703 by simply continuing to single-step. We have already
6704 executed the solib function (backwards), and a few
6705 steps will take us back through the trampoline to the
6711 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6713 /* We're doing a "next".
6715 Normal (forward) execution: set a breakpoint at the
6716 callee's return address (the address at which the caller
6719 Reverse (backward) execution. set the step-resume
6720 breakpoint at the start of the function that we just
6721 stepped into (backwards), and continue to there. When we
6722 get there, we'll need to single-step back to the caller. */
6724 if (execution_direction
== EXEC_REVERSE
)
6726 /* If we're already at the start of the function, we've either
6727 just stepped backward into a single instruction function,
6728 or stepped back out of a signal handler to the first instruction
6729 of the function. Just keep going, which will single-step back
6731 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6733 struct symtab_and_line sr_sal
;
6735 /* Normal function call return (static or dynamic). */
6737 sr_sal
.pc
= ecs
->stop_func_start
;
6738 sr_sal
.pspace
= get_frame_program_space (frame
);
6739 insert_step_resume_breakpoint_at_sal (gdbarch
,
6740 sr_sal
, null_frame_id
);
6744 insert_step_resume_breakpoint_at_caller (frame
);
6750 /* If we are in a function call trampoline (a stub between the
6751 calling routine and the real function), locate the real
6752 function. That's what tells us (a) whether we want to step
6753 into it at all, and (b) what prologue we want to run to the
6754 end of, if we do step into it. */
6755 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6756 if (real_stop_pc
== 0)
6757 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6758 if (real_stop_pc
!= 0)
6759 ecs
->stop_func_start
= real_stop_pc
;
6761 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6763 struct symtab_and_line sr_sal
;
6766 sr_sal
.pc
= ecs
->stop_func_start
;
6767 sr_sal
.pspace
= get_frame_program_space (frame
);
6769 insert_step_resume_breakpoint_at_sal (gdbarch
,
6770 sr_sal
, null_frame_id
);
6775 /* If we have line number information for the function we are
6776 thinking of stepping into and the function isn't on the skip
6779 If there are several symtabs at that PC (e.g. with include
6780 files), just want to know whether *any* of them have line
6781 numbers. find_pc_line handles this. */
6783 struct symtab_and_line tmp_sal
;
6785 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6786 if (tmp_sal
.line
!= 0
6787 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6790 if (execution_direction
== EXEC_REVERSE
)
6791 handle_step_into_function_backward (gdbarch
, ecs
);
6793 handle_step_into_function (gdbarch
, ecs
);
6798 /* If we have no line number and the step-stop-if-no-debug is
6799 set, we stop the step so that the user has a chance to switch
6800 in assembly mode. */
6801 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6802 && step_stop_if_no_debug
)
6804 end_stepping_range (ecs
);
6808 if (execution_direction
== EXEC_REVERSE
)
6810 /* If we're already at the start of the function, we've either just
6811 stepped backward into a single instruction function without line
6812 number info, or stepped back out of a signal handler to the first
6813 instruction of the function without line number info. Just keep
6814 going, which will single-step back to the caller. */
6815 if (ecs
->stop_func_start
!= stop_pc
)
6817 /* Set a breakpoint at callee's start address.
6818 From there we can step once and be back in the caller. */
6819 struct symtab_and_line sr_sal
;
6822 sr_sal
.pc
= ecs
->stop_func_start
;
6823 sr_sal
.pspace
= get_frame_program_space (frame
);
6824 insert_step_resume_breakpoint_at_sal (gdbarch
,
6825 sr_sal
, null_frame_id
);
6829 /* Set a breakpoint at callee's return address (the address
6830 at which the caller will resume). */
6831 insert_step_resume_breakpoint_at_caller (frame
);
6837 /* Reverse stepping through solib trampolines. */
6839 if (execution_direction
== EXEC_REVERSE
6840 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6842 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6843 || (ecs
->stop_func_start
== 0
6844 && in_solib_dynsym_resolve_code (stop_pc
)))
6846 /* Any solib trampoline code can be handled in reverse
6847 by simply continuing to single-step. We have already
6848 executed the solib function (backwards), and a few
6849 steps will take us back through the trampoline to the
6854 else if (in_solib_dynsym_resolve_code (stop_pc
))
6856 /* Stepped backward into the solib dynsym resolver.
6857 Set a breakpoint at its start and continue, then
6858 one more step will take us out. */
6859 struct symtab_and_line sr_sal
;
6862 sr_sal
.pc
= ecs
->stop_func_start
;
6863 sr_sal
.pspace
= get_frame_program_space (frame
);
6864 insert_step_resume_breakpoint_at_sal (gdbarch
,
6865 sr_sal
, null_frame_id
);
6871 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6873 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6874 the trampoline processing logic, however, there are some trampolines
6875 that have no names, so we should do trampoline handling first. */
6876 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6877 && ecs
->stop_func_name
== NULL
6878 && stop_pc_sal
.line
== 0)
6881 fprintf_unfiltered (gdb_stdlog
,
6882 "infrun: stepped into undebuggable function\n");
6884 /* The inferior just stepped into, or returned to, an
6885 undebuggable function (where there is no debugging information
6886 and no line number corresponding to the address where the
6887 inferior stopped). Since we want to skip this kind of code,
6888 we keep going until the inferior returns from this
6889 function - unless the user has asked us not to (via
6890 set step-mode) or we no longer know how to get back
6891 to the call site. */
6892 if (step_stop_if_no_debug
6893 || !frame_id_p (frame_unwind_caller_id (frame
)))
6895 /* If we have no line number and the step-stop-if-no-debug
6896 is set, we stop the step so that the user has a chance to
6897 switch in assembly mode. */
6898 end_stepping_range (ecs
);
6903 /* Set a breakpoint at callee's return address (the address
6904 at which the caller will resume). */
6905 insert_step_resume_breakpoint_at_caller (frame
);
6911 if (ecs
->event_thread
->control
.step_range_end
== 1)
6913 /* It is stepi or nexti. We always want to stop stepping after
6916 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6917 end_stepping_range (ecs
);
6921 if (stop_pc_sal
.line
== 0)
6923 /* We have no line number information. That means to stop
6924 stepping (does this always happen right after one instruction,
6925 when we do "s" in a function with no line numbers,
6926 or can this happen as a result of a return or longjmp?). */
6928 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6929 end_stepping_range (ecs
);
6933 /* Look for "calls" to inlined functions, part one. If the inline
6934 frame machinery detected some skipped call sites, we have entered
6935 a new inline function. */
6937 if (frame_id_eq (get_frame_id (get_current_frame ()),
6938 ecs
->event_thread
->control
.step_frame_id
)
6939 && inline_skipped_frames (ecs
->ptid
))
6941 struct symtab_and_line call_sal
;
6944 fprintf_unfiltered (gdb_stdlog
,
6945 "infrun: stepped into inlined function\n");
6947 find_frame_sal (get_current_frame (), &call_sal
);
6949 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6951 /* For "step", we're going to stop. But if the call site
6952 for this inlined function is on the same source line as
6953 we were previously stepping, go down into the function
6954 first. Otherwise stop at the call site. */
6956 if (call_sal
.line
== ecs
->event_thread
->current_line
6957 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6958 step_into_inline_frame (ecs
->ptid
);
6960 end_stepping_range (ecs
);
6965 /* For "next", we should stop at the call site if it is on a
6966 different source line. Otherwise continue through the
6967 inlined function. */
6968 if (call_sal
.line
== ecs
->event_thread
->current_line
6969 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6972 end_stepping_range (ecs
);
6977 /* Look for "calls" to inlined functions, part two. If we are still
6978 in the same real function we were stepping through, but we have
6979 to go further up to find the exact frame ID, we are stepping
6980 through a more inlined call beyond its call site. */
6982 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6983 && !frame_id_eq (get_frame_id (get_current_frame ()),
6984 ecs
->event_thread
->control
.step_frame_id
)
6985 && stepped_in_from (get_current_frame (),
6986 ecs
->event_thread
->control
.step_frame_id
))
6989 fprintf_unfiltered (gdb_stdlog
,
6990 "infrun: stepping through inlined function\n");
6992 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6995 end_stepping_range (ecs
);
6999 if ((stop_pc
== stop_pc_sal
.pc
)
7000 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
7001 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
7003 /* We are at the start of a different line. So stop. Note that
7004 we don't stop if we step into the middle of a different line.
7005 That is said to make things like for (;;) statements work
7008 fprintf_unfiltered (gdb_stdlog
,
7009 "infrun: stepped to a different line\n");
7010 end_stepping_range (ecs
);
7014 /* We aren't done stepping.
7016 Optimize by setting the stepping range to the line.
7017 (We might not be in the original line, but if we entered a
7018 new line in mid-statement, we continue stepping. This makes
7019 things like for(;;) statements work better.) */
7021 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7022 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7023 ecs
->event_thread
->control
.may_range_step
= 1;
7024 set_step_info (frame
, stop_pc_sal
);
7027 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
7031 /* In all-stop mode, if we're currently stepping but have stopped in
7032 some other thread, we may need to switch back to the stepped
7033 thread. Returns true we set the inferior running, false if we left
7034 it stopped (and the event needs further processing). */
7037 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7039 if (!target_is_non_stop_p ())
7041 struct thread_info
*tp
;
7042 struct thread_info
*stepping_thread
;
7044 /* If any thread is blocked on some internal breakpoint, and we
7045 simply need to step over that breakpoint to get it going
7046 again, do that first. */
7048 /* However, if we see an event for the stepping thread, then we
7049 know all other threads have been moved past their breakpoints
7050 already. Let the caller check whether the step is finished,
7051 etc., before deciding to move it past a breakpoint. */
7052 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7055 /* Check if the current thread is blocked on an incomplete
7056 step-over, interrupted by a random signal. */
7057 if (ecs
->event_thread
->control
.trap_expected
7058 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7062 fprintf_unfiltered (gdb_stdlog
,
7063 "infrun: need to finish step-over of [%s]\n",
7064 target_pid_to_str (ecs
->event_thread
->ptid
));
7070 /* Check if the current thread is blocked by a single-step
7071 breakpoint of another thread. */
7072 if (ecs
->hit_singlestep_breakpoint
)
7076 fprintf_unfiltered (gdb_stdlog
,
7077 "infrun: need to step [%s] over single-step "
7079 target_pid_to_str (ecs
->ptid
));
7085 /* If this thread needs yet another step-over (e.g., stepping
7086 through a delay slot), do it first before moving on to
7088 if (thread_still_needs_step_over (ecs
->event_thread
))
7092 fprintf_unfiltered (gdb_stdlog
,
7093 "infrun: thread [%s] still needs step-over\n",
7094 target_pid_to_str (ecs
->event_thread
->ptid
));
7100 /* If scheduler locking applies even if not stepping, there's no
7101 need to walk over threads. Above we've checked whether the
7102 current thread is stepping. If some other thread not the
7103 event thread is stepping, then it must be that scheduler
7104 locking is not in effect. */
7105 if (schedlock_applies (ecs
->event_thread
))
7108 /* Otherwise, we no longer expect a trap in the current thread.
7109 Clear the trap_expected flag before switching back -- this is
7110 what keep_going does as well, if we call it. */
7111 ecs
->event_thread
->control
.trap_expected
= 0;
7113 /* Likewise, clear the signal if it should not be passed. */
7114 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7115 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7117 /* Do all pending step-overs before actually proceeding with
7119 if (start_step_over ())
7121 prepare_to_wait (ecs
);
7125 /* Look for the stepping/nexting thread. */
7126 stepping_thread
= NULL
;
7128 ALL_NON_EXITED_THREADS (tp
)
7130 /* Ignore threads of processes the caller is not
7133 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
7136 /* When stepping over a breakpoint, we lock all threads
7137 except the one that needs to move past the breakpoint.
7138 If a non-event thread has this set, the "incomplete
7139 step-over" check above should have caught it earlier. */
7140 if (tp
->control
.trap_expected
)
7142 internal_error (__FILE__
, __LINE__
,
7143 "[%s] has inconsistent state: "
7144 "trap_expected=%d\n",
7145 target_pid_to_str (tp
->ptid
),
7146 tp
->control
.trap_expected
);
7149 /* Did we find the stepping thread? */
7150 if (tp
->control
.step_range_end
)
7152 /* Yep. There should only one though. */
7153 gdb_assert (stepping_thread
== NULL
);
7155 /* The event thread is handled at the top, before we
7157 gdb_assert (tp
!= ecs
->event_thread
);
7159 /* If some thread other than the event thread is
7160 stepping, then scheduler locking can't be in effect,
7161 otherwise we wouldn't have resumed the current event
7162 thread in the first place. */
7163 gdb_assert (!schedlock_applies (tp
));
7165 stepping_thread
= tp
;
7169 if (stepping_thread
!= NULL
)
7172 fprintf_unfiltered (gdb_stdlog
,
7173 "infrun: switching back to stepped thread\n");
7175 if (keep_going_stepped_thread (stepping_thread
))
7177 prepare_to_wait (ecs
);
7186 /* Set a previously stepped thread back to stepping. Returns true on
7187 success, false if the resume is not possible (e.g., the thread
7191 keep_going_stepped_thread (struct thread_info
*tp
)
7193 struct frame_info
*frame
;
7194 struct execution_control_state ecss
;
7195 struct execution_control_state
*ecs
= &ecss
;
7197 /* If the stepping thread exited, then don't try to switch back and
7198 resume it, which could fail in several different ways depending
7199 on the target. Instead, just keep going.
7201 We can find a stepping dead thread in the thread list in two
7204 - The target supports thread exit events, and when the target
7205 tries to delete the thread from the thread list, inferior_ptid
7206 pointed at the exiting thread. In such case, calling
7207 delete_thread does not really remove the thread from the list;
7208 instead, the thread is left listed, with 'exited' state.
7210 - The target's debug interface does not support thread exit
7211 events, and so we have no idea whatsoever if the previously
7212 stepping thread is still alive. For that reason, we need to
7213 synchronously query the target now. */
7215 if (is_exited (tp
->ptid
)
7216 || !target_thread_alive (tp
->ptid
))
7219 fprintf_unfiltered (gdb_stdlog
,
7220 "infrun: not resuming previously "
7221 "stepped thread, it has vanished\n");
7223 delete_thread (tp
->ptid
);
7228 fprintf_unfiltered (gdb_stdlog
,
7229 "infrun: resuming previously stepped thread\n");
7231 reset_ecs (ecs
, tp
);
7232 switch_to_thread (tp
->ptid
);
7234 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7235 frame
= get_current_frame ();
7237 /* If the PC of the thread we were trying to single-step has
7238 changed, then that thread has trapped or been signaled, but the
7239 event has not been reported to GDB yet. Re-poll the target
7240 looking for this particular thread's event (i.e. temporarily
7241 enable schedlock) by:
7243 - setting a break at the current PC
7244 - resuming that particular thread, only (by setting trap
7247 This prevents us continuously moving the single-step breakpoint
7248 forward, one instruction at a time, overstepping. */
7250 if (stop_pc
!= tp
->prev_pc
)
7255 fprintf_unfiltered (gdb_stdlog
,
7256 "infrun: expected thread advanced also (%s -> %s)\n",
7257 paddress (target_gdbarch (), tp
->prev_pc
),
7258 paddress (target_gdbarch (), stop_pc
));
7260 /* Clear the info of the previous step-over, as it's no longer
7261 valid (if the thread was trying to step over a breakpoint, it
7262 has already succeeded). It's what keep_going would do too,
7263 if we called it. Do this before trying to insert the sss
7264 breakpoint, otherwise if we were previously trying to step
7265 over this exact address in another thread, the breakpoint is
7267 clear_step_over_info ();
7268 tp
->control
.trap_expected
= 0;
7270 insert_single_step_breakpoint (get_frame_arch (frame
),
7271 get_frame_address_space (frame
),
7275 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7276 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7281 fprintf_unfiltered (gdb_stdlog
,
7282 "infrun: expected thread still hasn't advanced\n");
7284 keep_going_pass_signal (ecs
);
7289 /* Is thread TP in the middle of (software or hardware)
7290 single-stepping? (Note the result of this function must never be
7291 passed directly as target_resume's STEP parameter.) */
7294 currently_stepping (struct thread_info
*tp
)
7296 return ((tp
->control
.step_range_end
7297 && tp
->control
.step_resume_breakpoint
== NULL
)
7298 || tp
->control
.trap_expected
7299 || tp
->stepped_breakpoint
7300 || bpstat_should_step ());
7303 /* Inferior has stepped into a subroutine call with source code that
7304 we should not step over. Do step to the first line of code in
7308 handle_step_into_function (struct gdbarch
*gdbarch
,
7309 struct execution_control_state
*ecs
)
7311 struct compunit_symtab
*cust
;
7312 struct symtab_and_line stop_func_sal
, sr_sal
;
7314 fill_in_stop_func (gdbarch
, ecs
);
7316 cust
= find_pc_compunit_symtab (stop_pc
);
7317 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7318 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7319 ecs
->stop_func_start
);
7321 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7322 /* Use the step_resume_break to step until the end of the prologue,
7323 even if that involves jumps (as it seems to on the vax under
7325 /* If the prologue ends in the middle of a source line, continue to
7326 the end of that source line (if it is still within the function).
7327 Otherwise, just go to end of prologue. */
7328 if (stop_func_sal
.end
7329 && stop_func_sal
.pc
!= ecs
->stop_func_start
7330 && stop_func_sal
.end
< ecs
->stop_func_end
)
7331 ecs
->stop_func_start
= stop_func_sal
.end
;
7333 /* Architectures which require breakpoint adjustment might not be able
7334 to place a breakpoint at the computed address. If so, the test
7335 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7336 ecs->stop_func_start to an address at which a breakpoint may be
7337 legitimately placed.
7339 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7340 made, GDB will enter an infinite loop when stepping through
7341 optimized code consisting of VLIW instructions which contain
7342 subinstructions corresponding to different source lines. On
7343 FR-V, it's not permitted to place a breakpoint on any but the
7344 first subinstruction of a VLIW instruction. When a breakpoint is
7345 set, GDB will adjust the breakpoint address to the beginning of
7346 the VLIW instruction. Thus, we need to make the corresponding
7347 adjustment here when computing the stop address. */
7349 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7351 ecs
->stop_func_start
7352 = gdbarch_adjust_breakpoint_address (gdbarch
,
7353 ecs
->stop_func_start
);
7356 if (ecs
->stop_func_start
== stop_pc
)
7358 /* We are already there: stop now. */
7359 end_stepping_range (ecs
);
7364 /* Put the step-breakpoint there and go until there. */
7365 init_sal (&sr_sal
); /* initialize to zeroes */
7366 sr_sal
.pc
= ecs
->stop_func_start
;
7367 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7368 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7370 /* Do not specify what the fp should be when we stop since on
7371 some machines the prologue is where the new fp value is
7373 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7375 /* And make sure stepping stops right away then. */
7376 ecs
->event_thread
->control
.step_range_end
7377 = ecs
->event_thread
->control
.step_range_start
;
7382 /* Inferior has stepped backward into a subroutine call with source
7383 code that we should not step over. Do step to the beginning of the
7384 last line of code in it. */
7387 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7388 struct execution_control_state
*ecs
)
7390 struct compunit_symtab
*cust
;
7391 struct symtab_and_line stop_func_sal
;
7393 fill_in_stop_func (gdbarch
, ecs
);
7395 cust
= find_pc_compunit_symtab (stop_pc
);
7396 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7397 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7398 ecs
->stop_func_start
);
7400 stop_func_sal
= find_pc_line (stop_pc
, 0);
7402 /* OK, we're just going to keep stepping here. */
7403 if (stop_func_sal
.pc
== stop_pc
)
7405 /* We're there already. Just stop stepping now. */
7406 end_stepping_range (ecs
);
7410 /* Else just reset the step range and keep going.
7411 No step-resume breakpoint, they don't work for
7412 epilogues, which can have multiple entry paths. */
7413 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7414 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7420 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7421 This is used to both functions and to skip over code. */
7424 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7425 struct symtab_and_line sr_sal
,
7426 struct frame_id sr_id
,
7427 enum bptype sr_type
)
7429 /* There should never be more than one step-resume or longjmp-resume
7430 breakpoint per thread, so we should never be setting a new
7431 step_resume_breakpoint when one is already active. */
7432 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7433 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7436 fprintf_unfiltered (gdb_stdlog
,
7437 "infrun: inserting step-resume breakpoint at %s\n",
7438 paddress (gdbarch
, sr_sal
.pc
));
7440 inferior_thread ()->control
.step_resume_breakpoint
7441 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7445 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7446 struct symtab_and_line sr_sal
,
7447 struct frame_id sr_id
)
7449 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7454 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7455 This is used to skip a potential signal handler.
7457 This is called with the interrupted function's frame. The signal
7458 handler, when it returns, will resume the interrupted function at
7462 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7464 struct symtab_and_line sr_sal
;
7465 struct gdbarch
*gdbarch
;
7467 gdb_assert (return_frame
!= NULL
);
7468 init_sal (&sr_sal
); /* initialize to zeros */
7470 gdbarch
= get_frame_arch (return_frame
);
7471 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7472 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7473 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7475 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7476 get_stack_frame_id (return_frame
),
7480 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7481 is used to skip a function after stepping into it (for "next" or if
7482 the called function has no debugging information).
7484 The current function has almost always been reached by single
7485 stepping a call or return instruction. NEXT_FRAME belongs to the
7486 current function, and the breakpoint will be set at the caller's
7489 This is a separate function rather than reusing
7490 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7491 get_prev_frame, which may stop prematurely (see the implementation
7492 of frame_unwind_caller_id for an example). */
7495 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7497 struct symtab_and_line sr_sal
;
7498 struct gdbarch
*gdbarch
;
7500 /* We shouldn't have gotten here if we don't know where the call site
7502 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7504 init_sal (&sr_sal
); /* initialize to zeros */
7506 gdbarch
= frame_unwind_caller_arch (next_frame
);
7507 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7508 frame_unwind_caller_pc (next_frame
));
7509 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7510 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7512 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7513 frame_unwind_caller_id (next_frame
));
7516 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7517 new breakpoint at the target of a jmp_buf. The handling of
7518 longjmp-resume uses the same mechanisms used for handling
7519 "step-resume" breakpoints. */
7522 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7524 /* There should never be more than one longjmp-resume breakpoint per
7525 thread, so we should never be setting a new
7526 longjmp_resume_breakpoint when one is already active. */
7527 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7530 fprintf_unfiltered (gdb_stdlog
,
7531 "infrun: inserting longjmp-resume breakpoint at %s\n",
7532 paddress (gdbarch
, pc
));
7534 inferior_thread ()->control
.exception_resume_breakpoint
=
7535 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7538 /* Insert an exception resume breakpoint. TP is the thread throwing
7539 the exception. The block B is the block of the unwinder debug hook
7540 function. FRAME is the frame corresponding to the call to this
7541 function. SYM is the symbol of the function argument holding the
7542 target PC of the exception. */
7545 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7546 const struct block
*b
,
7547 struct frame_info
*frame
,
7552 struct block_symbol vsym
;
7553 struct value
*value
;
7555 struct breakpoint
*bp
;
7557 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
7558 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7559 /* If the value was optimized out, revert to the old behavior. */
7560 if (! value_optimized_out (value
))
7562 handler
= value_as_address (value
);
7565 fprintf_unfiltered (gdb_stdlog
,
7566 "infrun: exception resume at %lx\n",
7567 (unsigned long) handler
);
7569 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7570 handler
, bp_exception_resume
);
7572 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7575 bp
->thread
= tp
->global_num
;
7576 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7579 CATCH (e
, RETURN_MASK_ERROR
)
7581 /* We want to ignore errors here. */
7586 /* A helper for check_exception_resume that sets an
7587 exception-breakpoint based on a SystemTap probe. */
7590 insert_exception_resume_from_probe (struct thread_info
*tp
,
7591 const struct bound_probe
*probe
,
7592 struct frame_info
*frame
)
7594 struct value
*arg_value
;
7596 struct breakpoint
*bp
;
7598 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7602 handler
= value_as_address (arg_value
);
7605 fprintf_unfiltered (gdb_stdlog
,
7606 "infrun: exception resume at %s\n",
7607 paddress (get_objfile_arch (probe
->objfile
),
7610 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7611 handler
, bp_exception_resume
);
7612 bp
->thread
= tp
->global_num
;
7613 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7616 /* This is called when an exception has been intercepted. Check to
7617 see whether the exception's destination is of interest, and if so,
7618 set an exception resume breakpoint there. */
7621 check_exception_resume (struct execution_control_state
*ecs
,
7622 struct frame_info
*frame
)
7624 struct bound_probe probe
;
7625 struct symbol
*func
;
7627 /* First see if this exception unwinding breakpoint was set via a
7628 SystemTap probe point. If so, the probe has two arguments: the
7629 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7630 set a breakpoint there. */
7631 probe
= find_probe_by_pc (get_frame_pc (frame
));
7634 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7638 func
= get_frame_function (frame
);
7644 const struct block
*b
;
7645 struct block_iterator iter
;
7649 /* The exception breakpoint is a thread-specific breakpoint on
7650 the unwinder's debug hook, declared as:
7652 void _Unwind_DebugHook (void *cfa, void *handler);
7654 The CFA argument indicates the frame to which control is
7655 about to be transferred. HANDLER is the destination PC.
7657 We ignore the CFA and set a temporary breakpoint at HANDLER.
7658 This is not extremely efficient but it avoids issues in gdb
7659 with computing the DWARF CFA, and it also works even in weird
7660 cases such as throwing an exception from inside a signal
7663 b
= SYMBOL_BLOCK_VALUE (func
);
7664 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7666 if (!SYMBOL_IS_ARGUMENT (sym
))
7673 insert_exception_resume_breakpoint (ecs
->event_thread
,
7679 CATCH (e
, RETURN_MASK_ERROR
)
7686 stop_waiting (struct execution_control_state
*ecs
)
7689 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7691 clear_step_over_info ();
7693 /* Let callers know we don't want to wait for the inferior anymore. */
7694 ecs
->wait_some_more
= 0;
7696 /* If all-stop, but the target is always in non-stop mode, stop all
7697 threads now that we're presenting the stop to the user. */
7698 if (!non_stop
&& target_is_non_stop_p ())
7699 stop_all_threads ();
7702 /* Like keep_going, but passes the signal to the inferior, even if the
7703 signal is set to nopass. */
7706 keep_going_pass_signal (struct execution_control_state
*ecs
)
7708 /* Make sure normal_stop is called if we get a QUIT handled before
7710 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
7712 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7713 gdb_assert (!ecs
->event_thread
->resumed
);
7715 /* Save the pc before execution, to compare with pc after stop. */
7716 ecs
->event_thread
->prev_pc
7717 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7719 if (ecs
->event_thread
->control
.trap_expected
)
7721 struct thread_info
*tp
= ecs
->event_thread
;
7724 fprintf_unfiltered (gdb_stdlog
,
7725 "infrun: %s has trap_expected set, "
7726 "resuming to collect trap\n",
7727 target_pid_to_str (tp
->ptid
));
7729 /* We haven't yet gotten our trap, and either: intercepted a
7730 non-signal event (e.g., a fork); or took a signal which we
7731 are supposed to pass through to the inferior. Simply
7733 discard_cleanups (old_cleanups
);
7734 resume (ecs
->event_thread
->suspend
.stop_signal
);
7736 else if (step_over_info_valid_p ())
7738 /* Another thread is stepping over a breakpoint in-line. If
7739 this thread needs a step-over too, queue the request. In
7740 either case, this resume must be deferred for later. */
7741 struct thread_info
*tp
= ecs
->event_thread
;
7743 if (ecs
->hit_singlestep_breakpoint
7744 || thread_still_needs_step_over (tp
))
7747 fprintf_unfiltered (gdb_stdlog
,
7748 "infrun: step-over already in progress: "
7749 "step-over for %s deferred\n",
7750 target_pid_to_str (tp
->ptid
));
7751 thread_step_over_chain_enqueue (tp
);
7756 fprintf_unfiltered (gdb_stdlog
,
7757 "infrun: step-over in progress: "
7758 "resume of %s deferred\n",
7759 target_pid_to_str (tp
->ptid
));
7762 discard_cleanups (old_cleanups
);
7766 struct regcache
*regcache
= get_current_regcache ();
7769 step_over_what step_what
;
7771 /* Either the trap was not expected, but we are continuing
7772 anyway (if we got a signal, the user asked it be passed to
7775 We got our expected trap, but decided we should resume from
7778 We're going to run this baby now!
7780 Note that insert_breakpoints won't try to re-insert
7781 already inserted breakpoints. Therefore, we don't
7782 care if breakpoints were already inserted, or not. */
7784 /* If we need to step over a breakpoint, and we're not using
7785 displaced stepping to do so, insert all breakpoints
7786 (watchpoints, etc.) but the one we're stepping over, step one
7787 instruction, and then re-insert the breakpoint when that step
7790 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7792 remove_bp
= (ecs
->hit_singlestep_breakpoint
7793 || (step_what
& STEP_OVER_BREAKPOINT
));
7794 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7796 /* We can't use displaced stepping if we need to step past a
7797 watchpoint. The instruction copied to the scratch pad would
7798 still trigger the watchpoint. */
7800 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7802 set_step_over_info (get_regcache_aspace (regcache
),
7803 regcache_read_pc (regcache
), remove_wps
,
7804 ecs
->event_thread
->global_num
);
7806 else if (remove_wps
)
7807 set_step_over_info (NULL
, 0, remove_wps
, -1);
7809 /* If we now need to do an in-line step-over, we need to stop
7810 all other threads. Note this must be done before
7811 insert_breakpoints below, because that removes the breakpoint
7812 we're about to step over, otherwise other threads could miss
7814 if (step_over_info_valid_p () && target_is_non_stop_p ())
7815 stop_all_threads ();
7817 /* Stop stepping if inserting breakpoints fails. */
7820 insert_breakpoints ();
7822 CATCH (e
, RETURN_MASK_ERROR
)
7824 exception_print (gdb_stderr
, e
);
7826 discard_cleanups (old_cleanups
);
7831 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7833 discard_cleanups (old_cleanups
);
7834 resume (ecs
->event_thread
->suspend
.stop_signal
);
7837 prepare_to_wait (ecs
);
7840 /* Called when we should continue running the inferior, because the
7841 current event doesn't cause a user visible stop. This does the
7842 resuming part; waiting for the next event is done elsewhere. */
7845 keep_going (struct execution_control_state
*ecs
)
7847 if (ecs
->event_thread
->control
.trap_expected
7848 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7849 ecs
->event_thread
->control
.trap_expected
= 0;
7851 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7852 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7853 keep_going_pass_signal (ecs
);
7856 /* This function normally comes after a resume, before
7857 handle_inferior_event exits. It takes care of any last bits of
7858 housekeeping, and sets the all-important wait_some_more flag. */
7861 prepare_to_wait (struct execution_control_state
*ecs
)
7864 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7866 ecs
->wait_some_more
= 1;
7868 if (!target_is_async_p ())
7869 mark_infrun_async_event_handler ();
7872 /* We are done with the step range of a step/next/si/ni command.
7873 Called once for each n of a "step n" operation. */
7876 end_stepping_range (struct execution_control_state
*ecs
)
7878 ecs
->event_thread
->control
.stop_step
= 1;
7882 /* Several print_*_reason functions to print why the inferior has stopped.
7883 We always print something when the inferior exits, or receives a signal.
7884 The rest of the cases are dealt with later on in normal_stop and
7885 print_it_typical. Ideally there should be a call to one of these
7886 print_*_reason functions functions from handle_inferior_event each time
7887 stop_waiting is called.
7889 Note that we don't call these directly, instead we delegate that to
7890 the interpreters, through observers. Interpreters then call these
7891 with whatever uiout is right. */
7894 print_end_stepping_range_reason (struct ui_out
*uiout
)
7896 /* For CLI-like interpreters, print nothing. */
7898 if (ui_out_is_mi_like_p (uiout
))
7900 ui_out_field_string (uiout
, "reason",
7901 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7906 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7908 annotate_signalled ();
7909 if (ui_out_is_mi_like_p (uiout
))
7911 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7912 ui_out_text (uiout
, "\nProgram terminated with signal ");
7913 annotate_signal_name ();
7914 ui_out_field_string (uiout
, "signal-name",
7915 gdb_signal_to_name (siggnal
));
7916 annotate_signal_name_end ();
7917 ui_out_text (uiout
, ", ");
7918 annotate_signal_string ();
7919 ui_out_field_string (uiout
, "signal-meaning",
7920 gdb_signal_to_string (siggnal
));
7921 annotate_signal_string_end ();
7922 ui_out_text (uiout
, ".\n");
7923 ui_out_text (uiout
, "The program no longer exists.\n");
7927 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7929 struct inferior
*inf
= current_inferior ();
7930 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7932 annotate_exited (exitstatus
);
7935 if (ui_out_is_mi_like_p (uiout
))
7936 ui_out_field_string (uiout
, "reason",
7937 async_reason_lookup (EXEC_ASYNC_EXITED
));
7938 ui_out_text (uiout
, "[Inferior ");
7939 ui_out_text (uiout
, plongest (inf
->num
));
7940 ui_out_text (uiout
, " (");
7941 ui_out_text (uiout
, pidstr
);
7942 ui_out_text (uiout
, ") exited with code ");
7943 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
7944 ui_out_text (uiout
, "]\n");
7948 if (ui_out_is_mi_like_p (uiout
))
7950 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7951 ui_out_text (uiout
, "[Inferior ");
7952 ui_out_text (uiout
, plongest (inf
->num
));
7953 ui_out_text (uiout
, " (");
7954 ui_out_text (uiout
, pidstr
);
7955 ui_out_text (uiout
, ") exited normally]\n");
7959 /* Some targets/architectures can do extra processing/display of
7960 segmentation faults. E.g., Intel MPX boundary faults.
7961 Call the architecture dependent function to handle the fault. */
7964 handle_segmentation_fault (struct ui_out
*uiout
)
7966 struct regcache
*regcache
= get_current_regcache ();
7967 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7969 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7970 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7974 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7976 struct thread_info
*thr
= inferior_thread ();
7980 if (ui_out_is_mi_like_p (uiout
))
7982 else if (show_thread_that_caused_stop ())
7986 ui_out_text (uiout
, "\nThread ");
7987 ui_out_field_fmt (uiout
, "thread-id", "%s", print_thread_id (thr
));
7989 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7992 ui_out_text (uiout
, " \"");
7993 ui_out_field_fmt (uiout
, "name", "%s", name
);
7994 ui_out_text (uiout
, "\"");
7998 ui_out_text (uiout
, "\nProgram");
8000 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
8001 ui_out_text (uiout
, " stopped");
8004 ui_out_text (uiout
, " received signal ");
8005 annotate_signal_name ();
8006 if (ui_out_is_mi_like_p (uiout
))
8008 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
8009 ui_out_field_string (uiout
, "signal-name",
8010 gdb_signal_to_name (siggnal
));
8011 annotate_signal_name_end ();
8012 ui_out_text (uiout
, ", ");
8013 annotate_signal_string ();
8014 ui_out_field_string (uiout
, "signal-meaning",
8015 gdb_signal_to_string (siggnal
));
8017 if (siggnal
== GDB_SIGNAL_SEGV
)
8018 handle_segmentation_fault (uiout
);
8020 annotate_signal_string_end ();
8022 ui_out_text (uiout
, ".\n");
8026 print_no_history_reason (struct ui_out
*uiout
)
8028 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
8031 /* Print current location without a level number, if we have changed
8032 functions or hit a breakpoint. Print source line if we have one.
8033 bpstat_print contains the logic deciding in detail what to print,
8034 based on the event(s) that just occurred. */
8037 print_stop_location (struct target_waitstatus
*ws
)
8040 enum print_what source_flag
;
8041 int do_frame_printing
= 1;
8042 struct thread_info
*tp
= inferior_thread ();
8044 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8048 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8049 should) carry around the function and does (or should) use
8050 that when doing a frame comparison. */
8051 if (tp
->control
.stop_step
8052 && frame_id_eq (tp
->control
.step_frame_id
,
8053 get_frame_id (get_current_frame ()))
8054 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
8056 /* Finished step, just print source line. */
8057 source_flag
= SRC_LINE
;
8061 /* Print location and source line. */
8062 source_flag
= SRC_AND_LOC
;
8065 case PRINT_SRC_AND_LOC
:
8066 /* Print location and source line. */
8067 source_flag
= SRC_AND_LOC
;
8069 case PRINT_SRC_ONLY
:
8070 source_flag
= SRC_LINE
;
8073 /* Something bogus. */
8074 source_flag
= SRC_LINE
;
8075 do_frame_printing
= 0;
8078 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8081 /* The behavior of this routine with respect to the source
8083 SRC_LINE: Print only source line
8084 LOCATION: Print only location
8085 SRC_AND_LOC: Print location and source line. */
8086 if (do_frame_printing
)
8087 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8093 print_stop_event (struct ui_out
*uiout
)
8095 struct target_waitstatus last
;
8097 struct thread_info
*tp
;
8099 get_last_target_status (&last_ptid
, &last
);
8102 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8104 print_stop_location (&last
);
8106 /* Display the auto-display expressions. */
8110 tp
= inferior_thread ();
8111 if (tp
->thread_fsm
!= NULL
8112 && thread_fsm_finished_p (tp
->thread_fsm
))
8114 struct return_value_info
*rv
;
8116 rv
= thread_fsm_return_value (tp
->thread_fsm
);
8118 print_return_value (uiout
, rv
);
8125 maybe_remove_breakpoints (void)
8127 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
8129 if (remove_breakpoints ())
8131 target_terminal_ours_for_output ();
8132 printf_filtered (_("Cannot remove breakpoints because "
8133 "program is no longer writable.\nFurther "
8134 "execution is probably impossible.\n"));
8139 /* The execution context that just caused a normal stop. */
8146 /* The event PTID. */
8150 /* If stopp for a thread event, this is the thread that caused the
8152 struct thread_info
*thread
;
8154 /* The inferior that caused the stop. */
8158 /* Returns a new stop context. If stopped for a thread event, this
8159 takes a strong reference to the thread. */
8161 static struct stop_context
*
8162 save_stop_context (void)
8164 struct stop_context
*sc
= XNEW (struct stop_context
);
8166 sc
->stop_id
= get_stop_id ();
8167 sc
->ptid
= inferior_ptid
;
8168 sc
->inf_num
= current_inferior ()->num
;
8170 if (!ptid_equal (inferior_ptid
, null_ptid
))
8172 /* Take a strong reference so that the thread can't be deleted
8174 sc
->thread
= inferior_thread ();
8175 sc
->thread
->refcount
++;
8183 /* Release a stop context previously created with save_stop_context.
8184 Releases the strong reference to the thread as well. */
8187 release_stop_context_cleanup (void *arg
)
8189 struct stop_context
*sc
= (struct stop_context
*) arg
;
8191 if (sc
->thread
!= NULL
)
8192 sc
->thread
->refcount
--;
8196 /* Return true if the current context no longer matches the saved stop
8200 stop_context_changed (struct stop_context
*prev
)
8202 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
8204 if (prev
->inf_num
!= current_inferior ()->num
)
8206 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
8208 if (get_stop_id () != prev
->stop_id
)
8218 struct target_waitstatus last
;
8220 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
8223 get_last_target_status (&last_ptid
, &last
);
8227 /* If an exception is thrown from this point on, make sure to
8228 propagate GDB's knowledge of the executing state to the
8229 frontend/user running state. A QUIT is an easy exception to see
8230 here, so do this before any filtered output. */
8232 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
8233 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8234 || last
.kind
== TARGET_WAITKIND_EXITED
)
8236 /* On some targets, we may still have live threads in the
8237 inferior when we get a process exit event. E.g., for
8238 "checkpoint", when the current checkpoint/fork exits,
8239 linux-fork.c automatically switches to another fork from
8240 within target_mourn_inferior. */
8241 if (!ptid_equal (inferior_ptid
, null_ptid
))
8243 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8244 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8247 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8248 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8250 /* As we're presenting a stop, and potentially removing breakpoints,
8251 update the thread list so we can tell whether there are threads
8252 running on the target. With target remote, for example, we can
8253 only learn about new threads when we explicitly update the thread
8254 list. Do this before notifying the interpreters about signal
8255 stops, end of stepping ranges, etc., so that the "new thread"
8256 output is emitted before e.g., "Program received signal FOO",
8257 instead of after. */
8258 update_thread_list ();
8260 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8261 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
8263 /* As with the notification of thread events, we want to delay
8264 notifying the user that we've switched thread context until
8265 the inferior actually stops.
8267 There's no point in saying anything if the inferior has exited.
8268 Note that SIGNALLED here means "exited with a signal", not
8269 "received a signal".
8271 Also skip saying anything in non-stop mode. In that mode, as we
8272 don't want GDB to switch threads behind the user's back, to avoid
8273 races where the user is typing a command to apply to thread x,
8274 but GDB switches to thread y before the user finishes entering
8275 the command, fetch_inferior_event installs a cleanup to restore
8276 the current thread back to the thread the user had selected right
8277 after this event is handled, so we're not really switching, only
8278 informing of a stop. */
8280 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8281 && target_has_execution
8282 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8283 && last
.kind
!= TARGET_WAITKIND_EXITED
8284 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8286 SWITCH_THRU_ALL_UIS ()
8288 target_terminal_ours_for_output ();
8289 printf_filtered (_("[Switching to %s]\n"),
8290 target_pid_to_str (inferior_ptid
));
8291 annotate_thread_changed ();
8293 previous_inferior_ptid
= inferior_ptid
;
8296 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8298 SWITCH_THRU_ALL_UIS ()
8299 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8301 target_terminal_ours_for_output ();
8302 printf_filtered (_("No unwaited-for children left.\n"));
8306 /* Note: this depends on the update_thread_list call above. */
8307 maybe_remove_breakpoints ();
8309 /* If an auto-display called a function and that got a signal,
8310 delete that auto-display to avoid an infinite recursion. */
8312 if (stopped_by_random_signal
)
8313 disable_current_display ();
8315 SWITCH_THRU_ALL_UIS ()
8317 async_enable_stdin ();
8320 /* Let the user/frontend see the threads as stopped. */
8321 do_cleanups (old_chain
);
8323 /* Select innermost stack frame - i.e., current frame is frame 0,
8324 and current location is based on that. Handle the case where the
8325 dummy call is returning after being stopped. E.g. the dummy call
8326 previously hit a breakpoint. (If the dummy call returns
8327 normally, we won't reach here.) Do this before the stop hook is
8328 run, so that it doesn't get to see the temporary dummy frame,
8329 which is not where we'll present the stop. */
8330 if (has_stack_frames ())
8332 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8334 /* Pop the empty frame that contains the stack dummy. This
8335 also restores inferior state prior to the call (struct
8336 infcall_suspend_state). */
8337 struct frame_info
*frame
= get_current_frame ();
8339 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8341 /* frame_pop calls reinit_frame_cache as the last thing it
8342 does which means there's now no selected frame. */
8345 select_frame (get_current_frame ());
8347 /* Set the current source location. */
8348 set_current_sal_from_frame (get_current_frame ());
8351 /* Look up the hook_stop and run it (CLI internally handles problem
8352 of stop_command's pre-hook not existing). */
8353 if (stop_command
!= NULL
)
8355 struct stop_context
*saved_context
= save_stop_context ();
8356 struct cleanup
*old_chain
8357 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8359 catch_errors (hook_stop_stub
, stop_command
,
8360 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
8362 /* If the stop hook resumes the target, then there's no point in
8363 trying to notify about the previous stop; its context is
8364 gone. Likewise if the command switches thread or inferior --
8365 the observers would print a stop for the wrong
8367 if (stop_context_changed (saved_context
))
8369 do_cleanups (old_chain
);
8372 do_cleanups (old_chain
);
8375 /* Notify observers about the stop. This is where the interpreters
8376 print the stop event. */
8377 if (!ptid_equal (inferior_ptid
, null_ptid
))
8378 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
8381 observer_notify_normal_stop (NULL
, stop_print_frame
);
8383 annotate_stopped ();
8385 if (target_has_execution
)
8387 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8388 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8389 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8390 Delete any breakpoint that is to be deleted at the next stop. */
8391 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8394 /* Try to get rid of automatically added inferiors that are no
8395 longer needed. Keeping those around slows down things linearly.
8396 Note that this never removes the current inferior. */
8403 hook_stop_stub (void *cmd
)
8405 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
8410 signal_stop_state (int signo
)
8412 return signal_stop
[signo
];
8416 signal_print_state (int signo
)
8418 return signal_print
[signo
];
8422 signal_pass_state (int signo
)
8424 return signal_program
[signo
];
8428 signal_cache_update (int signo
)
8432 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8433 signal_cache_update (signo
);
8438 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8439 && signal_print
[signo
] == 0
8440 && signal_program
[signo
] == 1
8441 && signal_catch
[signo
] == 0);
8445 signal_stop_update (int signo
, int state
)
8447 int ret
= signal_stop
[signo
];
8449 signal_stop
[signo
] = state
;
8450 signal_cache_update (signo
);
8455 signal_print_update (int signo
, int state
)
8457 int ret
= signal_print
[signo
];
8459 signal_print
[signo
] = state
;
8460 signal_cache_update (signo
);
8465 signal_pass_update (int signo
, int state
)
8467 int ret
= signal_program
[signo
];
8469 signal_program
[signo
] = state
;
8470 signal_cache_update (signo
);
8474 /* Update the global 'signal_catch' from INFO and notify the
8478 signal_catch_update (const unsigned int *info
)
8482 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8483 signal_catch
[i
] = info
[i
] > 0;
8484 signal_cache_update (-1);
8485 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8489 sig_print_header (void)
8491 printf_filtered (_("Signal Stop\tPrint\tPass "
8492 "to program\tDescription\n"));
8496 sig_print_info (enum gdb_signal oursig
)
8498 const char *name
= gdb_signal_to_name (oursig
);
8499 int name_padding
= 13 - strlen (name
);
8501 if (name_padding
<= 0)
8504 printf_filtered ("%s", name
);
8505 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8506 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8507 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8508 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8509 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8512 /* Specify how various signals in the inferior should be handled. */
8515 handle_command (char *args
, int from_tty
)
8518 int digits
, wordlen
;
8519 int sigfirst
, signum
, siglast
;
8520 enum gdb_signal oursig
;
8523 unsigned char *sigs
;
8524 struct cleanup
*old_chain
;
8528 error_no_arg (_("signal to handle"));
8531 /* Allocate and zero an array of flags for which signals to handle. */
8533 nsigs
= (int) GDB_SIGNAL_LAST
;
8534 sigs
= (unsigned char *) alloca (nsigs
);
8535 memset (sigs
, 0, nsigs
);
8537 /* Break the command line up into args. */
8539 argv
= gdb_buildargv (args
);
8540 old_chain
= make_cleanup_freeargv (argv
);
8542 /* Walk through the args, looking for signal oursigs, signal names, and
8543 actions. Signal numbers and signal names may be interspersed with
8544 actions, with the actions being performed for all signals cumulatively
8545 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8547 while (*argv
!= NULL
)
8549 wordlen
= strlen (*argv
);
8550 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
8554 sigfirst
= siglast
= -1;
8556 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
8558 /* Apply action to all signals except those used by the
8559 debugger. Silently skip those. */
8562 siglast
= nsigs
- 1;
8564 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
8566 SET_SIGS (nsigs
, sigs
, signal_stop
);
8567 SET_SIGS (nsigs
, sigs
, signal_print
);
8569 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
8571 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8573 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
8575 SET_SIGS (nsigs
, sigs
, signal_print
);
8577 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
8579 SET_SIGS (nsigs
, sigs
, signal_program
);
8581 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
8583 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8585 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
8587 SET_SIGS (nsigs
, sigs
, signal_program
);
8589 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
8591 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8592 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8594 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
8596 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8598 else if (digits
> 0)
8600 /* It is numeric. The numeric signal refers to our own
8601 internal signal numbering from target.h, not to host/target
8602 signal number. This is a feature; users really should be
8603 using symbolic names anyway, and the common ones like
8604 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8606 sigfirst
= siglast
= (int)
8607 gdb_signal_from_command (atoi (*argv
));
8608 if ((*argv
)[digits
] == '-')
8611 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
8613 if (sigfirst
> siglast
)
8615 /* Bet he didn't figure we'd think of this case... */
8623 oursig
= gdb_signal_from_name (*argv
);
8624 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8626 sigfirst
= siglast
= (int) oursig
;
8630 /* Not a number and not a recognized flag word => complain. */
8631 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
8635 /* If any signal numbers or symbol names were found, set flags for
8636 which signals to apply actions to. */
8638 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8640 switch ((enum gdb_signal
) signum
)
8642 case GDB_SIGNAL_TRAP
:
8643 case GDB_SIGNAL_INT
:
8644 if (!allsigs
&& !sigs
[signum
])
8646 if (query (_("%s is used by the debugger.\n\
8647 Are you sure you want to change it? "),
8648 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8654 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8655 gdb_flush (gdb_stdout
);
8660 case GDB_SIGNAL_DEFAULT
:
8661 case GDB_SIGNAL_UNKNOWN
:
8662 /* Make sure that "all" doesn't print these. */
8673 for (signum
= 0; signum
< nsigs
; signum
++)
8676 signal_cache_update (-1);
8677 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8678 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8682 /* Show the results. */
8683 sig_print_header ();
8684 for (; signum
< nsigs
; signum
++)
8686 sig_print_info ((enum gdb_signal
) signum
);
8692 do_cleanups (old_chain
);
8695 /* Complete the "handle" command. */
8697 static VEC (char_ptr
) *
8698 handle_completer (struct cmd_list_element
*ignore
,
8699 const char *text
, const char *word
)
8701 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
8702 static const char * const keywords
[] =
8716 vec_signals
= signal_completer (ignore
, text
, word
);
8717 vec_keywords
= complete_on_enum (keywords
, word
, word
);
8719 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
8720 VEC_free (char_ptr
, vec_signals
);
8721 VEC_free (char_ptr
, vec_keywords
);
8726 gdb_signal_from_command (int num
)
8728 if (num
>= 1 && num
<= 15)
8729 return (enum gdb_signal
) num
;
8730 error (_("Only signals 1-15 are valid as numeric signals.\n\
8731 Use \"info signals\" for a list of symbolic signals."));
8734 /* Print current contents of the tables set by the handle command.
8735 It is possible we should just be printing signals actually used
8736 by the current target (but for things to work right when switching
8737 targets, all signals should be in the signal tables). */
8740 signals_info (char *signum_exp
, int from_tty
)
8742 enum gdb_signal oursig
;
8744 sig_print_header ();
8748 /* First see if this is a symbol name. */
8749 oursig
= gdb_signal_from_name (signum_exp
);
8750 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8752 /* No, try numeric. */
8754 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8756 sig_print_info (oursig
);
8760 printf_filtered ("\n");
8761 /* These ugly casts brought to you by the native VAX compiler. */
8762 for (oursig
= GDB_SIGNAL_FIRST
;
8763 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8764 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8768 if (oursig
!= GDB_SIGNAL_UNKNOWN
8769 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8770 sig_print_info (oursig
);
8773 printf_filtered (_("\nUse the \"handle\" command "
8774 "to change these tables.\n"));
8777 /* The $_siginfo convenience variable is a bit special. We don't know
8778 for sure the type of the value until we actually have a chance to
8779 fetch the data. The type can change depending on gdbarch, so it is
8780 also dependent on which thread you have selected.
8782 1. making $_siginfo be an internalvar that creates a new value on
8785 2. making the value of $_siginfo be an lval_computed value. */
8787 /* This function implements the lval_computed support for reading a
8791 siginfo_value_read (struct value
*v
)
8793 LONGEST transferred
;
8795 /* If we can access registers, so can we access $_siginfo. Likewise
8797 validate_registers_access ();
8800 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8802 value_contents_all_raw (v
),
8804 TYPE_LENGTH (value_type (v
)));
8806 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8807 error (_("Unable to read siginfo"));
8810 /* This function implements the lval_computed support for writing a
8814 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8816 LONGEST transferred
;
8818 /* If we can access registers, so can we access $_siginfo. Likewise
8820 validate_registers_access ();
8822 transferred
= target_write (¤t_target
,
8823 TARGET_OBJECT_SIGNAL_INFO
,
8825 value_contents_all_raw (fromval
),
8827 TYPE_LENGTH (value_type (fromval
)));
8829 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8830 error (_("Unable to write siginfo"));
8833 static const struct lval_funcs siginfo_value_funcs
=
8839 /* Return a new value with the correct type for the siginfo object of
8840 the current thread using architecture GDBARCH. Return a void value
8841 if there's no object available. */
8843 static struct value
*
8844 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8847 if (target_has_stack
8848 && !ptid_equal (inferior_ptid
, null_ptid
)
8849 && gdbarch_get_siginfo_type_p (gdbarch
))
8851 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8853 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8856 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8860 /* infcall_suspend_state contains state about the program itself like its
8861 registers and any signal it received when it last stopped.
8862 This state must be restored regardless of how the inferior function call
8863 ends (either successfully, or after it hits a breakpoint or signal)
8864 if the program is to properly continue where it left off. */
8866 struct infcall_suspend_state
8868 struct thread_suspend_state thread_suspend
;
8872 struct regcache
*registers
;
8874 /* Format of SIGINFO_DATA or NULL if it is not present. */
8875 struct gdbarch
*siginfo_gdbarch
;
8877 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8878 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8879 content would be invalid. */
8880 gdb_byte
*siginfo_data
;
8883 struct infcall_suspend_state
*
8884 save_infcall_suspend_state (void)
8886 struct infcall_suspend_state
*inf_state
;
8887 struct thread_info
*tp
= inferior_thread ();
8888 struct regcache
*regcache
= get_current_regcache ();
8889 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8890 gdb_byte
*siginfo_data
= NULL
;
8892 if (gdbarch_get_siginfo_type_p (gdbarch
))
8894 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8895 size_t len
= TYPE_LENGTH (type
);
8896 struct cleanup
*back_to
;
8898 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8899 back_to
= make_cleanup (xfree
, siginfo_data
);
8901 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8902 siginfo_data
, 0, len
) == len
)
8903 discard_cleanups (back_to
);
8906 /* Errors ignored. */
8907 do_cleanups (back_to
);
8908 siginfo_data
= NULL
;
8912 inf_state
= XCNEW (struct infcall_suspend_state
);
8916 inf_state
->siginfo_gdbarch
= gdbarch
;
8917 inf_state
->siginfo_data
= siginfo_data
;
8920 inf_state
->thread_suspend
= tp
->suspend
;
8922 /* run_inferior_call will not use the signal due to its `proceed' call with
8923 GDB_SIGNAL_0 anyway. */
8924 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8926 inf_state
->stop_pc
= stop_pc
;
8928 inf_state
->registers
= regcache_dup (regcache
);
8933 /* Restore inferior session state to INF_STATE. */
8936 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8938 struct thread_info
*tp
= inferior_thread ();
8939 struct regcache
*regcache
= get_current_regcache ();
8940 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8942 tp
->suspend
= inf_state
->thread_suspend
;
8944 stop_pc
= inf_state
->stop_pc
;
8946 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8948 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8950 /* Errors ignored. */
8951 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8952 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8955 /* The inferior can be gone if the user types "print exit(0)"
8956 (and perhaps other times). */
8957 if (target_has_execution
)
8958 /* NB: The register write goes through to the target. */
8959 regcache_cpy (regcache
, inf_state
->registers
);
8961 discard_infcall_suspend_state (inf_state
);
8965 do_restore_infcall_suspend_state_cleanup (void *state
)
8967 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
8971 make_cleanup_restore_infcall_suspend_state
8972 (struct infcall_suspend_state
*inf_state
)
8974 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8978 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8980 regcache_xfree (inf_state
->registers
);
8981 xfree (inf_state
->siginfo_data
);
8986 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8988 return inf_state
->registers
;
8991 /* infcall_control_state contains state regarding gdb's control of the
8992 inferior itself like stepping control. It also contains session state like
8993 the user's currently selected frame. */
8995 struct infcall_control_state
8997 struct thread_control_state thread_control
;
8998 struct inferior_control_state inferior_control
;
9001 enum stop_stack_kind stop_stack_dummy
;
9002 int stopped_by_random_signal
;
9004 /* ID if the selected frame when the inferior function call was made. */
9005 struct frame_id selected_frame_id
;
9008 /* Save all of the information associated with the inferior<==>gdb
9011 struct infcall_control_state
*
9012 save_infcall_control_state (void)
9014 struct infcall_control_state
*inf_status
=
9015 XNEW (struct infcall_control_state
);
9016 struct thread_info
*tp
= inferior_thread ();
9017 struct inferior
*inf
= current_inferior ();
9019 inf_status
->thread_control
= tp
->control
;
9020 inf_status
->inferior_control
= inf
->control
;
9022 tp
->control
.step_resume_breakpoint
= NULL
;
9023 tp
->control
.exception_resume_breakpoint
= NULL
;
9025 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9026 chain. If caller's caller is walking the chain, they'll be happier if we
9027 hand them back the original chain when restore_infcall_control_state is
9029 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9032 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9033 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9035 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
9041 restore_selected_frame (void *args
)
9043 struct frame_id
*fid
= (struct frame_id
*) args
;
9044 struct frame_info
*frame
;
9046 frame
= frame_find_by_id (*fid
);
9048 /* If inf_status->selected_frame_id is NULL, there was no previously
9052 warning (_("Unable to restore previously selected frame."));
9056 select_frame (frame
);
9061 /* Restore inferior session state to INF_STATUS. */
9064 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9066 struct thread_info
*tp
= inferior_thread ();
9067 struct inferior
*inf
= current_inferior ();
9069 if (tp
->control
.step_resume_breakpoint
)
9070 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9072 if (tp
->control
.exception_resume_breakpoint
)
9073 tp
->control
.exception_resume_breakpoint
->disposition
9074 = disp_del_at_next_stop
;
9076 /* Handle the bpstat_copy of the chain. */
9077 bpstat_clear (&tp
->control
.stop_bpstat
);
9079 tp
->control
= inf_status
->thread_control
;
9080 inf
->control
= inf_status
->inferior_control
;
9083 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9084 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9086 if (target_has_stack
)
9088 /* The point of catch_errors is that if the stack is clobbered,
9089 walking the stack might encounter a garbage pointer and
9090 error() trying to dereference it. */
9092 (restore_selected_frame
, &inf_status
->selected_frame_id
,
9093 "Unable to restore previously selected frame:\n",
9094 RETURN_MASK_ERROR
) == 0)
9095 /* Error in restoring the selected frame. Select the innermost
9097 select_frame (get_current_frame ());
9104 do_restore_infcall_control_state_cleanup (void *sts
)
9106 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
9110 make_cleanup_restore_infcall_control_state
9111 (struct infcall_control_state
*inf_status
)
9113 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
9117 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9119 if (inf_status
->thread_control
.step_resume_breakpoint
)
9120 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9121 = disp_del_at_next_stop
;
9123 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9124 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9125 = disp_del_at_next_stop
;
9127 /* See save_infcall_control_state for info on stop_bpstat. */
9128 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9133 /* restore_inferior_ptid() will be used by the cleanup machinery
9134 to restore the inferior_ptid value saved in a call to
9135 save_inferior_ptid(). */
9138 restore_inferior_ptid (void *arg
)
9140 ptid_t
*saved_ptid_ptr
= (ptid_t
*) arg
;
9142 inferior_ptid
= *saved_ptid_ptr
;
9146 /* Save the value of inferior_ptid so that it may be restored by a
9147 later call to do_cleanups(). Returns the struct cleanup pointer
9148 needed for later doing the cleanup. */
9151 save_inferior_ptid (void)
9153 ptid_t
*saved_ptid_ptr
= XNEW (ptid_t
);
9155 *saved_ptid_ptr
= inferior_ptid
;
9156 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
9162 clear_exit_convenience_vars (void)
9164 clear_internalvar (lookup_internalvar ("_exitsignal"));
9165 clear_internalvar (lookup_internalvar ("_exitcode"));
9169 /* User interface for reverse debugging:
9170 Set exec-direction / show exec-direction commands
9171 (returns error unless target implements to_set_exec_direction method). */
9173 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9174 static const char exec_forward
[] = "forward";
9175 static const char exec_reverse
[] = "reverse";
9176 static const char *exec_direction
= exec_forward
;
9177 static const char *const exec_direction_names
[] = {
9184 set_exec_direction_func (char *args
, int from_tty
,
9185 struct cmd_list_element
*cmd
)
9187 if (target_can_execute_reverse
)
9189 if (!strcmp (exec_direction
, exec_forward
))
9190 execution_direction
= EXEC_FORWARD
;
9191 else if (!strcmp (exec_direction
, exec_reverse
))
9192 execution_direction
= EXEC_REVERSE
;
9196 exec_direction
= exec_forward
;
9197 error (_("Target does not support this operation."));
9202 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9203 struct cmd_list_element
*cmd
, const char *value
)
9205 switch (execution_direction
) {
9207 fprintf_filtered (out
, _("Forward.\n"));
9210 fprintf_filtered (out
, _("Reverse.\n"));
9213 internal_error (__FILE__
, __LINE__
,
9214 _("bogus execution_direction value: %d"),
9215 (int) execution_direction
);
9220 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9221 struct cmd_list_element
*c
, const char *value
)
9223 fprintf_filtered (file
, _("Resuming the execution of threads "
9224 "of all processes is %s.\n"), value
);
9227 /* Implementation of `siginfo' variable. */
9229 static const struct internalvar_funcs siginfo_funcs
=
9236 /* Callback for infrun's target events source. This is marked when a
9237 thread has a pending status to process. */
9240 infrun_async_inferior_event_handler (gdb_client_data data
)
9242 inferior_event_handler (INF_REG_EVENT
, NULL
);
9246 _initialize_infrun (void)
9250 struct cmd_list_element
*c
;
9252 /* Register extra event sources in the event loop. */
9253 infrun_async_inferior_event_token
9254 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9256 add_info ("signals", signals_info
, _("\
9257 What debugger does when program gets various signals.\n\
9258 Specify a signal as argument to print info on that signal only."));
9259 add_info_alias ("handle", "signals", 0);
9261 c
= add_com ("handle", class_run
, handle_command
, _("\
9262 Specify how to handle signals.\n\
9263 Usage: handle SIGNAL [ACTIONS]\n\
9264 Args are signals and actions to apply to those signals.\n\
9265 If no actions are specified, the current settings for the specified signals\n\
9266 will be displayed instead.\n\
9268 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9269 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9270 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9271 The special arg \"all\" is recognized to mean all signals except those\n\
9272 used by the debugger, typically SIGTRAP and SIGINT.\n\
9274 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9275 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9276 Stop means reenter debugger if this signal happens (implies print).\n\
9277 Print means print a message if this signal happens.\n\
9278 Pass means let program see this signal; otherwise program doesn't know.\n\
9279 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9280 Pass and Stop may be combined.\n\
9282 Multiple signals may be specified. Signal numbers and signal names\n\
9283 may be interspersed with actions, with the actions being performed for\n\
9284 all signals cumulatively specified."));
9285 set_cmd_completer (c
, handle_completer
);
9288 stop_command
= add_cmd ("stop", class_obscure
,
9289 not_just_help_class_command
, _("\
9290 There is no `stop' command, but you can set a hook on `stop'.\n\
9291 This allows you to set a list of commands to be run each time execution\n\
9292 of the program stops."), &cmdlist
);
9294 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9295 Set inferior debugging."), _("\
9296 Show inferior debugging."), _("\
9297 When non-zero, inferior specific debugging is enabled."),
9300 &setdebuglist
, &showdebuglist
);
9302 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9303 &debug_displaced
, _("\
9304 Set displaced stepping debugging."), _("\
9305 Show displaced stepping debugging."), _("\
9306 When non-zero, displaced stepping specific debugging is enabled."),
9308 show_debug_displaced
,
9309 &setdebuglist
, &showdebuglist
);
9311 add_setshow_boolean_cmd ("non-stop", no_class
,
9313 Set whether gdb controls the inferior in non-stop mode."), _("\
9314 Show whether gdb controls the inferior in non-stop mode."), _("\
9315 When debugging a multi-threaded program and this setting is\n\
9316 off (the default, also called all-stop mode), when one thread stops\n\
9317 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9318 all other threads in the program while you interact with the thread of\n\
9319 interest. When you continue or step a thread, you can allow the other\n\
9320 threads to run, or have them remain stopped, but while you inspect any\n\
9321 thread's state, all threads stop.\n\
9323 In non-stop mode, when one thread stops, other threads can continue\n\
9324 to run freely. You'll be able to step each thread independently,\n\
9325 leave it stopped or free to run as needed."),
9331 numsigs
= (int) GDB_SIGNAL_LAST
;
9332 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9333 signal_print
= XNEWVEC (unsigned char, numsigs
);
9334 signal_program
= XNEWVEC (unsigned char, numsigs
);
9335 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9336 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9337 for (i
= 0; i
< numsigs
; i
++)
9340 signal_print
[i
] = 1;
9341 signal_program
[i
] = 1;
9342 signal_catch
[i
] = 0;
9345 /* Signals caused by debugger's own actions should not be given to
9346 the program afterwards.
9348 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9349 explicitly specifies that it should be delivered to the target
9350 program. Typically, that would occur when a user is debugging a
9351 target monitor on a simulator: the target monitor sets a
9352 breakpoint; the simulator encounters this breakpoint and halts
9353 the simulation handing control to GDB; GDB, noting that the stop
9354 address doesn't map to any known breakpoint, returns control back
9355 to the simulator; the simulator then delivers the hardware
9356 equivalent of a GDB_SIGNAL_TRAP to the program being
9358 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9359 signal_program
[GDB_SIGNAL_INT
] = 0;
9361 /* Signals that are not errors should not normally enter the debugger. */
9362 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9363 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9364 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9365 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9366 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9367 signal_print
[GDB_SIGNAL_PROF
] = 0;
9368 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9369 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9370 signal_stop
[GDB_SIGNAL_IO
] = 0;
9371 signal_print
[GDB_SIGNAL_IO
] = 0;
9372 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9373 signal_print
[GDB_SIGNAL_POLL
] = 0;
9374 signal_stop
[GDB_SIGNAL_URG
] = 0;
9375 signal_print
[GDB_SIGNAL_URG
] = 0;
9376 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9377 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9378 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9379 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9381 /* These signals are used internally by user-level thread
9382 implementations. (See signal(5) on Solaris.) Like the above
9383 signals, a healthy program receives and handles them as part of
9384 its normal operation. */
9385 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9386 signal_print
[GDB_SIGNAL_LWP
] = 0;
9387 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9388 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9389 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9390 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9391 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9392 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9394 /* Update cached state. */
9395 signal_cache_update (-1);
9397 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9398 &stop_on_solib_events
, _("\
9399 Set stopping for shared library events."), _("\
9400 Show stopping for shared library events."), _("\
9401 If nonzero, gdb will give control to the user when the dynamic linker\n\
9402 notifies gdb of shared library events. The most common event of interest\n\
9403 to the user would be loading/unloading of a new library."),
9404 set_stop_on_solib_events
,
9405 show_stop_on_solib_events
,
9406 &setlist
, &showlist
);
9408 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9409 follow_fork_mode_kind_names
,
9410 &follow_fork_mode_string
, _("\
9411 Set debugger response to a program call of fork or vfork."), _("\
9412 Show debugger response to a program call of fork or vfork."), _("\
9413 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9414 parent - the original process is debugged after a fork\n\
9415 child - the new process is debugged after a fork\n\
9416 The unfollowed process will continue to run.\n\
9417 By default, the debugger will follow the parent process."),
9419 show_follow_fork_mode_string
,
9420 &setlist
, &showlist
);
9422 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9423 follow_exec_mode_names
,
9424 &follow_exec_mode_string
, _("\
9425 Set debugger response to a program call of exec."), _("\
9426 Show debugger response to a program call of exec."), _("\
9427 An exec call replaces the program image of a process.\n\
9429 follow-exec-mode can be:\n\
9431 new - the debugger creates a new inferior and rebinds the process\n\
9432 to this new inferior. The program the process was running before\n\
9433 the exec call can be restarted afterwards by restarting the original\n\
9436 same - the debugger keeps the process bound to the same inferior.\n\
9437 The new executable image replaces the previous executable loaded in\n\
9438 the inferior. Restarting the inferior after the exec call restarts\n\
9439 the executable the process was running after the exec call.\n\
9441 By default, the debugger will use the same inferior."),
9443 show_follow_exec_mode_string
,
9444 &setlist
, &showlist
);
9446 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9447 scheduler_enums
, &scheduler_mode
, _("\
9448 Set mode for locking scheduler during execution."), _("\
9449 Show mode for locking scheduler during execution."), _("\
9450 off == no locking (threads may preempt at any time)\n\
9451 on == full locking (no thread except the current thread may run)\n\
9452 This applies to both normal execution and replay mode.\n\
9453 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9454 In this mode, other threads may run during other commands.\n\
9455 This applies to both normal execution and replay mode.\n\
9456 replay == scheduler locked in replay mode and unlocked during normal execution."),
9457 set_schedlock_func
, /* traps on target vector */
9458 show_scheduler_mode
,
9459 &setlist
, &showlist
);
9461 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9462 Set mode for resuming threads of all processes."), _("\
9463 Show mode for resuming threads of all processes."), _("\
9464 When on, execution commands (such as 'continue' or 'next') resume all\n\
9465 threads of all processes. When off (which is the default), execution\n\
9466 commands only resume the threads of the current process. The set of\n\
9467 threads that are resumed is further refined by the scheduler-locking\n\
9468 mode (see help set scheduler-locking)."),
9470 show_schedule_multiple
,
9471 &setlist
, &showlist
);
9473 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9474 Set mode of the step operation."), _("\
9475 Show mode of the step operation."), _("\
9476 When set, doing a step over a function without debug line information\n\
9477 will stop at the first instruction of that function. Otherwise, the\n\
9478 function is skipped and the step command stops at a different source line."),
9480 show_step_stop_if_no_debug
,
9481 &setlist
, &showlist
);
9483 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9484 &can_use_displaced_stepping
, _("\
9485 Set debugger's willingness to use displaced stepping."), _("\
9486 Show debugger's willingness to use displaced stepping."), _("\
9487 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9488 supported by the target architecture. If off, gdb will not use displaced\n\
9489 stepping to step over breakpoints, even if such is supported by the target\n\
9490 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9491 if the target architecture supports it and non-stop mode is active, but will not\n\
9492 use it in all-stop mode (see help set non-stop)."),
9494 show_can_use_displaced_stepping
,
9495 &setlist
, &showlist
);
9497 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9498 &exec_direction
, _("Set direction of execution.\n\
9499 Options are 'forward' or 'reverse'."),
9500 _("Show direction of execution (forward/reverse)."),
9501 _("Tells gdb whether to execute forward or backward."),
9502 set_exec_direction_func
, show_exec_direction_func
,
9503 &setlist
, &showlist
);
9505 /* Set/show detach-on-fork: user-settable mode. */
9507 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9508 Set whether gdb will detach the child of a fork."), _("\
9509 Show whether gdb will detach the child of a fork."), _("\
9510 Tells gdb whether to detach the child of a fork."),
9511 NULL
, NULL
, &setlist
, &showlist
);
9513 /* Set/show disable address space randomization mode. */
9515 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9516 &disable_randomization
, _("\
9517 Set disabling of debuggee's virtual address space randomization."), _("\
9518 Show disabling of debuggee's virtual address space randomization."), _("\
9519 When this mode is on (which is the default), randomization of the virtual\n\
9520 address space is disabled. Standalone programs run with the randomization\n\
9521 enabled by default on some platforms."),
9522 &set_disable_randomization
,
9523 &show_disable_randomization
,
9524 &setlist
, &showlist
);
9526 /* ptid initializations */
9527 inferior_ptid
= null_ptid
;
9528 target_last_wait_ptid
= minus_one_ptid
;
9530 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9531 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9532 observer_attach_thread_exit (infrun_thread_thread_exit
);
9533 observer_attach_inferior_exit (infrun_inferior_exit
);
9535 /* Explicitly create without lookup, since that tries to create a
9536 value with a void typed value, and when we get here, gdbarch
9537 isn't initialized yet. At this point, we're quite sure there
9538 isn't another convenience variable of the same name. */
9539 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9541 add_setshow_boolean_cmd ("observer", no_class
,
9542 &observer_mode_1
, _("\
9543 Set whether gdb controls the inferior in observer mode."), _("\
9544 Show whether gdb controls the inferior in observer mode."), _("\
9545 In observer mode, GDB can get data from the inferior, but not\n\
9546 affect its execution. Registers and memory may not be changed,\n\
9547 breakpoints may not be set, and the program cannot be interrupted\n\